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Diffstat (limited to 'gcc/go/gofrontend')
28 files changed, 54467 insertions, 0 deletions
diff --git a/gcc/go/gofrontend/LICENSE b/gcc/go/gofrontend/LICENSE new file mode 100644 index 000000000..6a66aea5e --- /dev/null +++ b/gcc/go/gofrontend/LICENSE @@ -0,0 +1,27 @@ +Copyright (c) 2009 The Go Authors. All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are +met: + + * Redistributions of source code must retain the above copyright +notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above +copyright notice, this list of conditions and the following disclaimer +in the documentation and/or other materials provided with the +distribution. + * Neither the name of Google Inc. nor the names of its +contributors may be used to endorse or promote products derived from +this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. diff --git a/gcc/go/gofrontend/PATENTS b/gcc/go/gofrontend/PATENTS new file mode 100644 index 000000000..733099041 --- /dev/null +++ b/gcc/go/gofrontend/PATENTS @@ -0,0 +1,22 @@ +Additional IP Rights Grant (Patents) + +"This implementation" means the copyrightable works distributed by +Google as part of the Go project. + +Google hereby grants to You a perpetual, worldwide, non-exclusive, +no-charge, royalty-free, irrevocable (except as stated in this section) +patent license to make, have made, use, offer to sell, sell, import, +transfer and otherwise run, modify and propagate the contents of this +implementation of Go, where such license applies only to those patent +claims, both currently owned or controlled by Google and acquired in +the future, licensable by Google that are necessarily infringed by this +implementation of Go. This grant does not include claims that would be +infringed only as a consequence of further modification of this +implementation. If you or your agent or exclusive licensee institute or +order or agree to the institution of patent litigation against any +entity (including a cross-claim or counterclaim in a lawsuit) alleging +that this implementation of Go or any code incorporated within this +implementation of Go constitutes direct or contributory patent +infringement, or inducement of patent infringement, then any patent +rights granted to you under this License for this implementation of Go +shall terminate as of the date such litigation is filed. diff --git a/gcc/go/gofrontend/README b/gcc/go/gofrontend/README new file mode 100644 index 000000000..859659e75 --- /dev/null +++ b/gcc/go/gofrontend/README @@ -0,0 +1,55 @@ +See ../README. + +The frontend is written in C++. + +The frontend lexes and parses the input into an IR specific to this +frontend known as gogo. It then runs a series of passes over the +code. + +Finally it converts gogo to gcc's GENERIC. A goal is to move the gcc +support code into a gcc-interface subdirectory. The gcc code will be +put under the GPL. The rest of the frontend will not include any gcc +header files. + +Issues to be faced in this transition: + +* Representation of source locations. + + Currently the frontend uses gcc's source_location codes, using the + interface in libcpp/line-map.h. + +* Handling of error messages. + + Currently the frontend uses gcc's error_at and warning_at + functions. + + Currently the frontend uses gcc's diagnostic formatter, using + features such as %<%> for appropriate quoting. + + Localization may be an issue. + +* Use of gcc_assert and gcc_unreachable. + +This compiler works, but the code is a work in progress. Notably, the +support for garbage collection is ineffective and needs a complete +rethinking. The frontend pays little attention to its memory usage +and rarely frees any memory. The code could use a general cleanup +which we have not had time to do. + +Contributing +============= + +To contribute patches to the files in this directory, please see +http://golang.org/doc/gccgo_contribute.html . + +The master copy of these files is hosted at +http://code.google.com/p/gofrontend . Changes to these files require +signing a Google contributor license agreement. If you are the +copyright holder, you will need to agree to the individual contributor +license agreement at +http://code.google.com/legal/individual-cla-v1.0.html. This agreement +can be completed online. + +If your organization is the copyright holder, the organization will +need to agree to the corporate contributor license agreement at +http://code.google.com/legal/corporate-cla-v1.0.html. + +If the copyright holder for your code has already completed the +agreement in connection with another Google open source project, it +does not need to be completed again. diff --git a/gcc/go/gofrontend/dataflow.cc b/gcc/go/gofrontend/dataflow.cc new file mode 100644 index 000000000..8170d0ac1 --- /dev/null +++ b/gcc/go/gofrontend/dataflow.cc @@ -0,0 +1,278 @@ +// dataflow.cc -- Go frontend dataflow. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include "gogo.h" +#include "expressions.h" +#include "statements.h" +#include "dataflow.h" + +// This class is used to traverse the tree to look for uses of +// variables. + +class Dataflow_traverse_expressions : public Traverse +{ + public: + Dataflow_traverse_expressions(Dataflow* dataflow, Statement* statement) + : Traverse(traverse_blocks | traverse_expressions), + dataflow_(dataflow), statement_(statement) + { } + + protected: + // Only look at top-level expressions: do not descend into blocks. + // They will be examined via Dataflow_traverse_statements. + int + block(Block*) + { return TRAVERSE_SKIP_COMPONENTS; } + + int + expression(Expression**); + + private: + // The dataflow information. + Dataflow* dataflow_; + // The Statement in which we are looking. + Statement* statement_; +}; + +// Given an expression, return the Named_object that it refers to, if +// it is a local variable. + +static Named_object* +get_var(Expression* expr) +{ + Var_expression* ve = expr->var_expression(); + if (ve == NULL) + return NULL; + Named_object* no = ve->named_object(); + gcc_assert(no->is_variable() || no->is_result_variable()); + if (no->is_variable() && no->var_value()->is_global()) + return NULL; + return no; +} + +// Look for a reference to a variable in an expression. + +int +Dataflow_traverse_expressions::expression(Expression** expr) +{ + Named_object* no = get_var(*expr); + if (no != NULL) + this->dataflow_->add_ref(no, this->statement_); + return TRAVERSE_CONTINUE; +} + +// This class is used to handle an assignment statement. + +class Dataflow_traverse_assignment : public Traverse_assignments +{ + public: + Dataflow_traverse_assignment(Dataflow* dataflow, Statement* statement) + : dataflow_(dataflow), statement_(statement) + { } + + protected: + void + initialize_variable(Named_object*); + + void + assignment(Expression** lhs, Expression** rhs); + + void + value(Expression**, bool, bool); + + private: + // The dataflow information. + Dataflow* dataflow_; + // The Statement in which we are looking. + Statement* statement_; +}; + +// Handle a variable initialization. + +void +Dataflow_traverse_assignment::initialize_variable(Named_object* var) +{ + Expression* init = var->var_value()->init(); + this->dataflow_->add_def(var, init, this->statement_, true); + if (init != NULL) + { + Expression* e = init; + this->value(&e, true, true); + gcc_assert(e == init); + } +} + +// Handle an assignment in a statement. + +void +Dataflow_traverse_assignment::assignment(Expression** plhs, Expression** prhs) +{ + Named_object* no = get_var(*plhs); + if (no != NULL) + { + Expression* rhs = prhs == NULL ? NULL : *prhs; + this->dataflow_->add_def(no, rhs, this->statement_, false); + } + else + { + // If this is not a variable it may be some computed lvalue, and + // we want to look for references to variables in that lvalue. + this->value(plhs, false, false); + } + if (prhs != NULL) + this->value(prhs, true, false); +} + +// Handle a value in a statement. + +void +Dataflow_traverse_assignment::value(Expression** pexpr, bool, bool) +{ + Named_object* no = get_var(*pexpr); + if (no != NULL) + this->dataflow_->add_ref(no, this->statement_); + else + { + Dataflow_traverse_expressions dte(this->dataflow_, this->statement_); + Expression::traverse(pexpr, &dte); + } +} + +// This class is used to traverse the tree to look for statements. + +class Dataflow_traverse_statements : public Traverse +{ + public: + Dataflow_traverse_statements(Dataflow* dataflow) + : Traverse(traverse_statements), + dataflow_(dataflow) + { } + + protected: + int + statement(Block*, size_t* pindex, Statement*); + + private: + // The dataflow information. + Dataflow* dataflow_; +}; + +// For each Statement, we look for expressions. + +int +Dataflow_traverse_statements::statement(Block* block, size_t* pindex, + Statement *statement) +{ + Dataflow_traverse_assignment dta(this->dataflow_, statement); + if (!statement->traverse_assignments(&dta)) + { + Dataflow_traverse_expressions dte(this->dataflow_, statement); + statement->traverse(block, pindex, &dte); + } + return TRAVERSE_CONTINUE; +} + +// Compare variables. + +bool +Dataflow::Compare_vars::operator()(const Named_object* no1, + const Named_object* no2) const +{ + if (no1->name() < no2->name()) + return true; + if (no1->name() > no2->name()) + return false; + + // We can have two different variables with the same name. + source_location loc1 = no1->location(); + source_location loc2 = no2->location(); + if (loc1 < loc2) + return false; + if (loc1 > loc2) + return true; + + if (no1 == no2) + return false; + + // We can't have two variables with the same name in the same + // location. + gcc_unreachable(); +} + +// Class Dataflow. + +Dataflow::Dataflow() + : defs_(), refs_() +{ +} + +// Build the dataflow information. + +void +Dataflow::initialize(Gogo* gogo) +{ + Dataflow_traverse_statements dts(this); + gogo->traverse(&dts); +} + +// Add a definition of a variable. + +void +Dataflow::add_def(Named_object* var, Expression* val, Statement* statement, + bool is_init) +{ + Defs* defnull = NULL; + std::pair<Defmap::iterator, bool> ins = + this->defs_.insert(std::make_pair(var, defnull)); + if (ins.second) + ins.first->second = new Defs; + Def def; + def.statement = statement; + def.val = val; + def.is_init = is_init; + ins.first->second->push_back(def); +} + +// Add a reference to a variable. + +void +Dataflow::add_ref(Named_object* var, Statement* statement) +{ + Refs* refnull = NULL; + std::pair<Refmap::iterator, bool> ins = + this->refs_.insert(std::make_pair(var, refnull)); + if (ins.second) + ins.first->second = new Refs; + Ref ref; + ref.statement = statement; + ins.first->second->push_back(ref); +} + +// Return the definitions of a variable. + +const Dataflow::Defs* +Dataflow::find_defs(Named_object* var) const +{ + Defmap::const_iterator p = this->defs_.find(var); + if (p == this->defs_.end()) + return NULL; + else + return p->second; +} + +// Return the references of a variable. + +const Dataflow::Refs* +Dataflow::find_refs(Named_object* var) const +{ + Refmap::const_iterator p = this->refs_.find(var); + if (p == this->refs_.end()) + return NULL; + else + return p->second; +} diff --git a/gcc/go/gofrontend/dataflow.h b/gcc/go/gofrontend/dataflow.h new file mode 100644 index 000000000..a75c8e661 --- /dev/null +++ b/gcc/go/gofrontend/dataflow.h @@ -0,0 +1,91 @@ +// dataflow.h -- Go frontend dataflow. -*- C++ -*- + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef GO_DATAFLOW_H +#define GO_DATAFLOW_H + +class Expression; +class Named_object; +class Statement; + +// Dataflow information about the Go program. + +class Dataflow +{ + public: + // A variable definition. + struct Def + { + // The statement where the variable is defined. + Statement* statement; + // The value to which the variable is set. This may be NULL. + Expression* val; + // Whether this is an initialization of the variable. + bool is_init; + }; + + // A variable reference. + struct Ref + { + // The statement where the variable is referenced. + Statement* statement; + }; + + // A list of defs. + typedef std::vector<Def> Defs; + + // A list of refs. + typedef std::vector<Ref> Refs; + + Dataflow(); + + // Initialize the dataflow information. + void + initialize(Gogo*); + + // Add a definition of a variable. STATEMENT assigns a value to + // VAR. VAL is the value if it is known, NULL otherwise. + void + add_def(Named_object* var, Expression* val, Statement* statement, + bool is_init); + + // Add a reference to a variable. VAR is the variable, and + // STATEMENT is the statement which refers to it. + void + add_ref(Named_object* var, Statement* statement); + + // Return the definitions of VAR--the places where it is set. + const Defs* + find_defs(Named_object* var) const; + + // Return the references to VAR--the places where it is used. + const Refs* + find_refs(Named_object* var) const; + + private: + // Order variables in the map. + struct Compare_vars + { + bool + operator()(const Named_object*, const Named_object*) const; + }; + + // Map from variables to a list of defs of the variable. We use a + // map rather than a hash table because the order in which we + // process variables may affect the resulting code. + typedef std::map<Named_object*, Defs*, Compare_vars> Defmap; + + // Map from variables to a list of refs to the vairable. + typedef std::map<Named_object*, Refs*, Compare_vars> Refmap; + + // Variable defs. + Defmap defs_; + // Variable refs; + Refmap refs_; +}; + + +#endif // !defined(GO_DATAFLOW_H) diff --git a/gcc/go/gofrontend/export.cc b/gcc/go/gofrontend/export.cc new file mode 100644 index 000000000..cbf24b840 --- /dev/null +++ b/gcc/go/gofrontend/export.cc @@ -0,0 +1,439 @@ +// export.cc -- Export declarations in Go frontend. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" +#include "sha1.h" + +#ifndef ENABLE_BUILD_WITH_CXX +extern "C" +{ +#endif + +#include "machmode.h" +#include "output.h" +#include "target.h" + +#ifndef ENABLE_BUILD_WITH_CXX +} +#endif + +#include "gogo.h" +#include "types.h" +#include "statements.h" +#include "export.h" + +// This file handles exporting global declarations. + +// Class Export. + +// Version 1 magic number. + +const int Export::v1_magic_len; + +const char Export::v1_magic[Export::v1_magic_len] = + { + 'v', '1', ';', '\n' + }; + +const int Export::v1_checksum_len; + +// Constructor. + +Export::Export(Stream* stream) + : stream_(stream), type_refs_(), type_index_(1) +{ +} + +// A functor to sort Named_object pointers by name. + +struct Sort_bindings +{ + bool + operator()(const Named_object* n1, const Named_object* n2) const + { return n1->name() < n2->name(); } +}; + +// Return true if we should export NO. + +static bool +should_export(Named_object* no) +{ + // We only export objects which are locally defined. + if (no->package() != NULL) + return false; + + // We don't export packages. + if (no->is_package()) + return false; + + // We don't export hidden names. + if (Gogo::is_hidden_name(no->name())) + return false; + + // We don't export nested functions. + if (no->is_function() && no->func_value()->enclosing() != NULL) + return false; + + // We don't export thunks. + if (no->is_function() && Gogo::is_thunk(no)) + return false; + + // Methods are exported with the type, not here. + if (no->is_function() + && no->func_value()->type()->is_method()) + return false; + if (no->is_function_declaration() + && no->func_declaration_value()->type()->is_method()) + return false; + + // Don't export dummy global variables created for initializers when + // used with sinks. + if (no->is_variable() && no->name()[0] == '_' && no->name()[1] == '.') + return false; + + return true; +} + +// Export those identifiers marked for exporting. + +void +Export::export_globals(const std::string& package_name, + const std::string& unique_prefix, + int package_priority, + const std::string& import_init_fn, + const std::set<Import_init>& imported_init_fns, + const Bindings* bindings) +{ + // If there have been any errors so far, don't try to export + // anything. That way the export code doesn't have to worry about + // mismatched types or other confusions. + if (saw_errors()) + return; + + // Export the symbols in sorted order. That will reduce cases where + // irrelevant changes to the source code affect the exported + // interface. + std::vector<Named_object*> exports; + exports.reserve(bindings->size_definitions()); + + for (Bindings::const_definitions_iterator p = bindings->begin_definitions(); + p != bindings->end_definitions(); + ++p) + if (should_export(*p)) + exports.push_back(*p); + + for (Bindings::const_declarations_iterator p = + bindings->begin_declarations(); + p != bindings->end_declarations(); + ++p) + { + // We export a function declaration as it may be implemented in + // supporting C code. We do not export type declarations. + if (p->second->is_function_declaration() + && should_export(p->second)) + exports.push_back(p->second); + } + + std::sort(exports.begin(), exports.end(), Sort_bindings()); + + // Although the export data is readable, at least this version is, + // it is conceptually a binary format. Start with a four byte + // verison number. + this->write_bytes(Export::v1_magic, Export::v1_magic_len); + + // The package name. + this->write_c_string("package "); + this->write_string(package_name); + this->write_c_string(";\n"); + + // The unique prefix. This prefix is used for all global symbols. + this->write_c_string("prefix "); + this->write_string(unique_prefix); + this->write_c_string(";\n"); + + // The package priority. + char buf[100]; + snprintf(buf, sizeof buf, "priority %d;\n", package_priority); + this->write_c_string(buf); + + this->write_imported_init_fns(package_name, package_priority, import_init_fn, + imported_init_fns); + + // FIXME: It might be clever to add something about the processor + // and ABI being used, although ideally any problems in that area + // would be caught by the linker. + + for (std::vector<Named_object*>::const_iterator p = exports.begin(); + p != exports.end(); + ++p) + (*p)->export_named_object(this); + + std::string checksum = this->stream_->checksum(); + std::string s = "checksum "; + for (std::string::const_iterator p = checksum.begin(); + p != checksum.end(); + ++p) + { + unsigned char c = *p; + unsigned int dig = c >> 4; + s += dig < 10 ? '0' + dig : 'A' + dig - 10; + dig = c & 0xf; + s += dig < 10 ? '0' + dig : 'A' + dig - 10; + } + s += ";\n"; + this->stream_->write_checksum(s); +} + +// Write out the import control variables for this package. + +void +Export::write_imported_init_fns( + const std::string& package_name, + int priority, + const std::string& import_init_fn, + const std::set<Import_init>& imported_init_fns) +{ + if (import_init_fn.empty() && imported_init_fns.empty()) + return; + + this->write_c_string("import"); + + if (!import_init_fn.empty()) + { + this->write_c_string(" "); + this->write_string(package_name); + this->write_c_string(" "); + this->write_string(import_init_fn); + char buf[100]; + snprintf(buf, sizeof buf, " %d", priority); + this->write_c_string(buf); + } + + if (!imported_init_fns.empty()) + { + // Sort the list of functions for more consistent output. + std::vector<Import_init> v; + for (std::set<Import_init>::const_iterator p = imported_init_fns.begin(); + p != imported_init_fns.end(); + ++p) + v.push_back(*p); + std::sort(v.begin(), v.end()); + + for (std::vector<Import_init>::const_iterator p = v.begin(); + p != v.end(); + ++p) + { + this->write_c_string(" "); + this->write_string(p->package_name()); + this->write_c_string(" "); + this->write_string(p->init_name()); + char buf[100]; + snprintf(buf, sizeof buf, " %d", p->priority()); + this->write_c_string(buf); + } + } + + this->write_c_string(";\n"); +} + +// Export a type. We have to ensure that on import we create a single +// Named_type node for each named type. We do this by keeping a hash +// table mapping named types to reference numbers. The first time we +// see a named type we assign it a reference number by making an entry +// in the hash table. If we see it again, we just refer to the +// reference number. + +// Named types are, of course, associated with packages. Note that we +// may see a named type when importing one package, and then later see +// the same named type when importing a different package. The home +// package may or may not be imported during this compilation. The +// reference number scheme has to get this all right. Basic approach +// taken from "On the Linearization of Graphs and Writing Symbol +// Files" by Robert Griesemer. + +void +Export::write_type(const Type* type) +{ + // We don't want to assign a reference number to a forward + // declaration to a type which was defined later. + type = type->forwarded(); + + Type_refs::const_iterator p = this->type_refs_.find(type); + if (p != this->type_refs_.end()) + { + // This type was already in the table. + int index = p->second; + gcc_assert(index != 0); + char buf[30]; + snprintf(buf, sizeof buf, "<type %d>", index); + this->write_c_string(buf); + return; + } + + const Named_type* named_type = type->named_type(); + const Forward_declaration_type* forward = type->forward_declaration_type(); + + int index = this->type_index_; + ++this->type_index_; + + char buf[30]; + snprintf(buf, sizeof buf, "<type %d ", index); + this->write_c_string(buf); + + if (named_type != NULL || forward != NULL) + { + const Named_object* named_object; + if (named_type != NULL) + { + // The builtin types should have been predefined. + gcc_assert(named_type->location() != BUILTINS_LOCATION + || (named_type->named_object()->package()->name() + == "unsafe")); + named_object = named_type->named_object(); + } + else + named_object = forward->named_object(); + + const Package* package = named_object->package(); + + std::string s = "\""; + if (package != NULL && !Gogo::is_hidden_name(named_object->name())) + { + s += package->unique_prefix(); + s += '.'; + s += package->name(); + s += '.'; + } + s += named_object->name(); + s += "\" "; + this->write_string(s); + + // We must add a named type to the table now, since the + // definition of the type may refer to the named type via a + // pointer. + this->type_refs_[type] = index; + } + + type->export_type(this); + + this->write_c_string(">"); + + if (named_type == NULL) + this->type_refs_[type] = index; +} + +// Add the builtin types to the export table. + +void +Export::register_builtin_types(Gogo* gogo) +{ + this->register_builtin_type(gogo, "int8", BUILTIN_INT8); + this->register_builtin_type(gogo, "int16", BUILTIN_INT16); + this->register_builtin_type(gogo, "int32", BUILTIN_INT32); + this->register_builtin_type(gogo, "int64", BUILTIN_INT64); + this->register_builtin_type(gogo, "uint8", BUILTIN_UINT8); + this->register_builtin_type(gogo, "uint16", BUILTIN_UINT16); + this->register_builtin_type(gogo, "uint32", BUILTIN_UINT32); + this->register_builtin_type(gogo, "uint64", BUILTIN_UINT64); + this->register_builtin_type(gogo, "float32", BUILTIN_FLOAT32); + this->register_builtin_type(gogo, "float64", BUILTIN_FLOAT64); + this->register_builtin_type(gogo, "complex64", BUILTIN_COMPLEX64); + this->register_builtin_type(gogo, "complex128", BUILTIN_COMPLEX128); + this->register_builtin_type(gogo, "int", BUILTIN_INT); + this->register_builtin_type(gogo, "uint", BUILTIN_UINT); + this->register_builtin_type(gogo, "uintptr", BUILTIN_UINTPTR); + this->register_builtin_type(gogo, "bool", BUILTIN_BOOL); + this->register_builtin_type(gogo, "string", BUILTIN_STRING); +} + +// Register one builtin type in the export table. + +void +Export::register_builtin_type(Gogo* gogo, const char* name, Builtin_code code) +{ + Named_object* named_object = gogo->lookup_global(name); + gcc_assert(named_object != NULL && named_object->is_type()); + std::pair<Type_refs::iterator, bool> ins = + this->type_refs_.insert(std::make_pair(named_object->type_value(), code)); + gcc_assert(ins.second); + + // We also insert the underlying type. We can see the underlying + // type at least for string and bool. + Type* real_type = named_object->type_value()->real_type(); + ins = this->type_refs_.insert(std::make_pair(real_type, code)); + gcc_assert(ins.second); +} + +// Class Export::Stream. + +Export::Stream::Stream() +{ + this->checksum_ = new sha1_ctx; + memset(this->checksum_, 0, sizeof(sha1_ctx)); + sha1_init_ctx(this->checksum_); +} + +Export::Stream::~Stream() +{ +} + +// Write bytes to the stream. This keeps a checksum of bytes as they +// go by. + +void +Export::Stream::write_and_sum_bytes(const char* bytes, size_t length) +{ + sha1_process_bytes(bytes, length, this->checksum_); + this->do_write(bytes, length); +} + +// Get the checksum. + +std::string +Export::Stream::checksum() +{ + // Use a union to provide the required alignment. + union + { + char checksum[Export::v1_checksum_len]; + long align; + } u; + sha1_finish_ctx(this->checksum_, u.checksum); + return std::string(u.checksum, Export::v1_checksum_len); +} + +// Write the checksum string to the export data. + +void +Export::Stream::write_checksum(const std::string& s) +{ + this->do_write(s.data(), s.length()); +} + +// Class Stream_to_section. + +Stream_to_section::Stream_to_section() + : section_(NULL) +{ +} + +// Write data to a section. + +void +Stream_to_section::do_write(const char* bytes, size_t length) +{ + section* sec = (section*) this->section_; + if (sec == NULL) + { + gcc_assert(targetm.have_named_sections); + + sec = get_section(".go_export", SECTION_DEBUG, NULL); + this->section_ = (void*) sec; + } + + switch_to_section(sec); + assemble_string(bytes, length); +} diff --git a/gcc/go/gofrontend/export.h b/gcc/go/gofrontend/export.h new file mode 100644 index 000000000..4a1fd2b64 --- /dev/null +++ b/gcc/go/gofrontend/export.h @@ -0,0 +1,189 @@ +// export.h -- Export declarations in Go frontend. -*- C++ -*- + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef GO_EXPORT_H +#define GO_EXPORT_H + +struct sha1_ctx; +class Gogo; +class Import_init; +class Bindings; +class Type; + +// Codes used for the builtin types. These are all negative to make +// them easily distinct from the codes assigned by Export::write_type. +// Note that these codes may not be changed! Changing them would +// break existing export data. + +enum Builtin_code +{ + BUILTIN_INT8 = -1, + BUILTIN_INT16 = -2, + BUILTIN_INT32 = -3, + BUILTIN_INT64 = -4, + BUILTIN_UINT8 = -5, + BUILTIN_UINT16 = -6, + BUILTIN_UINT32 = -7, + BUILTIN_UINT64 = -8, + BUILTIN_FLOAT32 = -9, + BUILTIN_FLOAT64 = -10, + BUILTIN_INT = -11, + BUILTIN_UINT = -12, + BUILTIN_UINTPTR = -13, + BUILTIN_BOOL = -15, + BUILTIN_STRING = -16, + BUILTIN_COMPLEX64 = -17, + BUILTIN_COMPLEX128 = -18, + + SMALLEST_BUILTIN_CODE = -18 +}; + +// This class manages exporting Go declarations. It handles the main +// loop of exporting. A pointer to this class is also passed to the +// various specific export implementations. + +class Export +{ + public: + // The Stream class is an interface used to output the exported + // information. The caller should instantiate a child of this + // class. + class Stream + { + public: + Stream(); + virtual ~Stream(); + + // Write a string. + void + write_string(const std::string& s) + { this->write_and_sum_bytes(s.data(), s.length()); } + + // Write a nul terminated string. + void + write_c_string(const char* s) + { this->write_and_sum_bytes(s, strlen(s)); } + + // Write some bytes. + void + write_bytes(const char* bytes, size_t length) + { this->write_and_sum_bytes(bytes, length); } + + // Return the raw bytes of the checksum data. + std::string + checksum(); + + // Write a checksum string to the stream. This will be called at + // the end of the other output. + void + write_checksum(const std::string&); + + protected: + // This function is called with data to export. This data must be + // made available as a contiguous stream for the importer. + virtual void + do_write(const char* bytes, size_t length) = 0; + + private: + void + write_and_sum_bytes(const char*, size_t); + + // The checksum. + sha1_ctx* checksum_; + }; + + Export(Stream*); + + // The magic code for version 1 export data. + static const int v1_magic_len = 4; + static const char v1_magic[v1_magic_len]; + + // The length of the v1 checksum string. + static const int v1_checksum_len = 20; + + // Register the builtin types. + void + register_builtin_types(Gogo*); + + // Export the identifiers in BINDINGS which are marked for export. + // The exporting is done via a series of calls to THIS->STREAM_. If + // is nothing to export, this->stream_->write will not be called. + // UNIQUE_PREFIX is a prefix for all global symbols. + // PACKAGE_PRIORITY is the priority to use for this package. + // IMPORT_INIT_FN is the name of the import initialization function + // for this package; it will be empty if none is needed. + // IMPORTED_INIT_FNS is the list of initialization functions for + // imported packages. + void + export_globals(const std::string& package_name, + const std::string& unique_prefix, + int package_priority, + const std::string& import_init_fn, + const std::set<Import_init>& imported_init_fns, + const Bindings* bindings); + + // Write a string to the export stream. + void + write_string(const std::string& s) + { this->stream_->write_string(s); } + + // Write a nul terminated string to the export stream. + void + write_c_string(const char* s) + { this->stream_->write_c_string(s); } + + // Write some bytes to the export stream. + void + write_bytes(const char* bytes, size_t length) + { this->stream_->write_bytes(bytes, length); } + + // Write out a type. This handles references back to previous + // definitions. + void + write_type(const Type*); + + private: + Export(const Export&); + Export& operator=(const Export&); + + // Write out the imported initialization functions. + void + write_imported_init_fns(const std::string& package_name, int priority, + const std::string&, const std::set<Import_init>&); + + // Register one builtin type. + void + register_builtin_type(Gogo*, const char* name, Builtin_code); + + // Mapping from Type objects to a constant index. + typedef Unordered_map(const Type*, int) Type_refs; + + // The stream to which we are writing data. + Stream* stream_; + // Type mappings. + Type_refs type_refs_; + // Index number of next type. + int type_index_; +}; + +// An export streamer which puts the export stream in a named section. + +class Stream_to_section : public Export::Stream +{ + public: + Stream_to_section(); + + protected: + void + do_write(const char*, size_t); + + private: + // The section we are writing to; this is really union section + // defined in output.h. + void* section_; +}; + +#endif // !defined(GO_EXPORT_H) diff --git a/gcc/go/gofrontend/expressions.cc b/gcc/go/gofrontend/expressions.cc new file mode 100644 index 000000000..8660c755a --- /dev/null +++ b/gcc/go/gofrontend/expressions.cc @@ -0,0 +1,12782 @@ +// expressions.cc -- Go frontend expression handling. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include <gmp.h> + +#ifndef ENABLE_BUILD_WITH_CXX +extern "C" +{ +#endif + +#include "toplev.h" +#include "intl.h" +#include "tree.h" +#include "gimple.h" +#include "tree-iterator.h" +#include "convert.h" +#include "real.h" +#include "realmpfr.h" + +#ifndef ENABLE_BUILD_WITH_CXX +} +#endif + +#include "go-c.h" +#include "gogo.h" +#include "types.h" +#include "export.h" +#include "import.h" +#include "statements.h" +#include "lex.h" +#include "expressions.h" + +// Class Expression. + +Expression::Expression(Expression_classification classification, + source_location location) + : classification_(classification), location_(location) +{ +} + +Expression::~Expression() +{ +} + +// If this expression has a constant integer value, return it. + +bool +Expression::integer_constant_value(bool iota_is_constant, mpz_t val, + Type** ptype) const +{ + *ptype = NULL; + return this->do_integer_constant_value(iota_is_constant, val, ptype); +} + +// If this expression has a constant floating point value, return it. + +bool +Expression::float_constant_value(mpfr_t val, Type** ptype) const +{ + *ptype = NULL; + if (this->do_float_constant_value(val, ptype)) + return true; + mpz_t ival; + mpz_init(ival); + Type* t; + bool ret; + if (!this->do_integer_constant_value(false, ival, &t)) + ret = false; + else + { + mpfr_set_z(val, ival, GMP_RNDN); + ret = true; + } + mpz_clear(ival); + return ret; +} + +// If this expression has a constant complex value, return it. + +bool +Expression::complex_constant_value(mpfr_t real, mpfr_t imag, + Type** ptype) const +{ + *ptype = NULL; + if (this->do_complex_constant_value(real, imag, ptype)) + return true; + Type *t; + if (this->float_constant_value(real, &t)) + { + mpfr_set_ui(imag, 0, GMP_RNDN); + return true; + } + return false; +} + +// Traverse the expressions. + +int +Expression::traverse(Expression** pexpr, Traverse* traverse) +{ + Expression* expr = *pexpr; + if ((traverse->traverse_mask() & Traverse::traverse_expressions) != 0) + { + int t = traverse->expression(pexpr); + if (t == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + else if (t == TRAVERSE_SKIP_COMPONENTS) + return TRAVERSE_CONTINUE; + } + return expr->do_traverse(traverse); +} + +// Traverse subexpressions of this expression. + +int +Expression::traverse_subexpressions(Traverse* traverse) +{ + return this->do_traverse(traverse); +} + +// Default implementation for do_traverse for child classes. + +int +Expression::do_traverse(Traverse*) +{ + return TRAVERSE_CONTINUE; +} + +// This virtual function is called by the parser if the value of this +// expression is being discarded. By default, we warn. Expressions +// with side effects override. + +void +Expression::do_discarding_value() +{ + this->warn_about_unused_value(); +} + +// This virtual function is called to export expressions. This will +// only be used by expressions which may be constant. + +void +Expression::do_export(Export*) const +{ + gcc_unreachable(); +} + +// Warn that the value of the expression is not used. + +void +Expression::warn_about_unused_value() +{ + warning_at(this->location(), OPT_Wunused_value, "value computed is not used"); +} + +// Note that this expression is an error. This is called by children +// when they discover an error. + +void +Expression::set_is_error() +{ + this->classification_ = EXPRESSION_ERROR; +} + +// For children to call to report an error conveniently. + +void +Expression::report_error(const char* msg) +{ + error_at(this->location_, "%s", msg); + this->set_is_error(); +} + +// Set types of variables and constants. This is implemented by the +// child class. + +void +Expression::determine_type(const Type_context* context) +{ + this->do_determine_type(context); +} + +// Set types when there is no context. + +void +Expression::determine_type_no_context() +{ + Type_context context; + this->do_determine_type(&context); +} + +// Return a tree handling any conversions which must be done during +// assignment. + +tree +Expression::convert_for_assignment(Translate_context* context, Type* lhs_type, + Type* rhs_type, tree rhs_tree, + source_location location) +{ + if (lhs_type == rhs_type) + return rhs_tree; + + if (lhs_type->is_error_type() || rhs_type->is_error_type()) + return error_mark_node; + + if (lhs_type->is_undefined() || rhs_type->is_undefined()) + { + // Make sure we report the error. + lhs_type->base(); + rhs_type->base(); + return error_mark_node; + } + + if (rhs_tree == error_mark_node || TREE_TYPE(rhs_tree) == error_mark_node) + return error_mark_node; + + Gogo* gogo = context->gogo(); + + tree lhs_type_tree = lhs_type->get_tree(gogo); + if (lhs_type_tree == error_mark_node) + return error_mark_node; + + if (lhs_type->interface_type() != NULL) + { + if (rhs_type->interface_type() == NULL) + return Expression::convert_type_to_interface(context, lhs_type, + rhs_type, rhs_tree, + location); + else + return Expression::convert_interface_to_interface(context, lhs_type, + rhs_type, rhs_tree, + false, location); + } + else if (rhs_type->interface_type() != NULL) + return Expression::convert_interface_to_type(context, lhs_type, rhs_type, + rhs_tree, location); + else if (lhs_type->is_open_array_type() + && rhs_type->is_nil_type()) + { + // Assigning nil to an open array. + gcc_assert(TREE_CODE(lhs_type_tree) == RECORD_TYPE); + + VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 3); + + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + tree field = TYPE_FIELDS(lhs_type_tree); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), + "__values") == 0); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), null_pointer_node); + + elt = VEC_quick_push(constructor_elt, init, NULL); + field = DECL_CHAIN(field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), + "__count") == 0); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), integer_zero_node); + + elt = VEC_quick_push(constructor_elt, init, NULL); + field = DECL_CHAIN(field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), + "__capacity") == 0); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), integer_zero_node); + + tree val = build_constructor(lhs_type_tree, init); + TREE_CONSTANT(val) = 1; + + return val; + } + else if (rhs_type->is_nil_type()) + { + // The left hand side should be a pointer type at the tree + // level. + gcc_assert(POINTER_TYPE_P(lhs_type_tree)); + return fold_convert(lhs_type_tree, null_pointer_node); + } + else if (lhs_type_tree == TREE_TYPE(rhs_tree)) + { + // No conversion is needed. + return rhs_tree; + } + else if (POINTER_TYPE_P(lhs_type_tree) + || INTEGRAL_TYPE_P(lhs_type_tree) + || SCALAR_FLOAT_TYPE_P(lhs_type_tree) + || COMPLEX_FLOAT_TYPE_P(lhs_type_tree)) + return fold_convert_loc(location, lhs_type_tree, rhs_tree); + else if (TREE_CODE(lhs_type_tree) == RECORD_TYPE + && TREE_CODE(TREE_TYPE(rhs_tree)) == RECORD_TYPE) + { + // This conversion must be permitted by Go, or we wouldn't have + // gotten here. + gcc_assert(int_size_in_bytes(lhs_type_tree) + == int_size_in_bytes(TREE_TYPE(rhs_tree))); + return fold_build1_loc(location, VIEW_CONVERT_EXPR, lhs_type_tree, + rhs_tree); + } + else + { + gcc_assert(useless_type_conversion_p(lhs_type_tree, TREE_TYPE(rhs_tree))); + return rhs_tree; + } +} + +// Return a tree for a conversion from a non-interface type to an +// interface type. + +tree +Expression::convert_type_to_interface(Translate_context* context, + Type* lhs_type, Type* rhs_type, + tree rhs_tree, source_location location) +{ + Gogo* gogo = context->gogo(); + Interface_type* lhs_interface_type = lhs_type->interface_type(); + bool lhs_is_empty = lhs_interface_type->is_empty(); + + // Since RHS_TYPE is a static type, we can create the interface + // method table at compile time. + + // When setting an interface to nil, we just set both fields to + // NULL. + if (rhs_type->is_nil_type()) + return lhs_type->get_init_tree(gogo, false); + + // This should have been checked already. + gcc_assert(lhs_interface_type->implements_interface(rhs_type, NULL)); + + tree lhs_type_tree = lhs_type->get_tree(gogo); + if (lhs_type_tree == error_mark_node) + return error_mark_node; + + // An interface is a tuple. If LHS_TYPE is an empty interface type, + // then the first field is the type descriptor for RHS_TYPE. + // Otherwise it is the interface method table for RHS_TYPE. + tree first_field_value; + if (lhs_is_empty) + first_field_value = rhs_type->type_descriptor_pointer(gogo); + else + { + // Build the interface method table for this interface and this + // object type: a list of function pointers for each interface + // method. + Named_type* rhs_named_type = rhs_type->named_type(); + bool is_pointer = false; + if (rhs_named_type == NULL) + { + rhs_named_type = rhs_type->deref()->named_type(); + is_pointer = true; + } + tree method_table; + if (rhs_named_type == NULL) + method_table = null_pointer_node; + else + method_table = + rhs_named_type->interface_method_table(gogo, lhs_interface_type, + is_pointer); + first_field_value = fold_convert_loc(location, const_ptr_type_node, + method_table); + } + if (first_field_value == error_mark_node) + return error_mark_node; + + // Start building a constructor for the value we will return. + + VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 2); + + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + tree field = TYPE_FIELDS(lhs_type_tree); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), + (lhs_is_empty ? "__type_descriptor" : "__methods")) == 0); + elt->index = field; + elt->value = fold_convert_loc(location, TREE_TYPE(field), first_field_value); + + elt = VEC_quick_push(constructor_elt, init, NULL); + field = DECL_CHAIN(field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__object") == 0); + elt->index = field; + + if (rhs_type->points_to() != NULL) + { + // We are assigning a pointer to the interface; the interface + // holds the pointer itself. + elt->value = rhs_tree; + return build_constructor(lhs_type_tree, init); + } + + // We are assigning a non-pointer value to the interface; the + // interface gets a copy of the value in the heap. + + tree object_size = TYPE_SIZE_UNIT(TREE_TYPE(rhs_tree)); + + tree space = gogo->allocate_memory(rhs_type, object_size, location); + space = fold_convert_loc(location, build_pointer_type(TREE_TYPE(rhs_tree)), + space); + space = save_expr(space); + + tree ref = build_fold_indirect_ref_loc(location, space); + TREE_THIS_NOTRAP(ref) = 1; + tree set = fold_build2_loc(location, MODIFY_EXPR, void_type_node, + ref, rhs_tree); + + elt->value = fold_convert_loc(location, TREE_TYPE(field), space); + + return build2(COMPOUND_EXPR, lhs_type_tree, set, + build_constructor(lhs_type_tree, init)); +} + +// Return a tree for the type descriptor of RHS_TREE, which has +// interface type RHS_TYPE. If RHS_TREE is nil the result will be +// NULL. + +tree +Expression::get_interface_type_descriptor(Translate_context*, + Type* rhs_type, tree rhs_tree, + source_location location) +{ + tree rhs_type_tree = TREE_TYPE(rhs_tree); + gcc_assert(TREE_CODE(rhs_type_tree) == RECORD_TYPE); + tree rhs_field = TYPE_FIELDS(rhs_type_tree); + tree v = build3(COMPONENT_REF, TREE_TYPE(rhs_field), rhs_tree, rhs_field, + NULL_TREE); + if (rhs_type->interface_type()->is_empty()) + { + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(rhs_field)), + "__type_descriptor") == 0); + return v; + } + + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(rhs_field)), "__methods") + == 0); + gcc_assert(POINTER_TYPE_P(TREE_TYPE(v))); + v = save_expr(v); + tree v1 = build_fold_indirect_ref_loc(location, v); + gcc_assert(TREE_CODE(TREE_TYPE(v1)) == RECORD_TYPE); + tree f = TYPE_FIELDS(TREE_TYPE(v1)); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(f)), "__type_descriptor") + == 0); + v1 = build3(COMPONENT_REF, TREE_TYPE(f), v1, f, NULL_TREE); + + tree eq = fold_build2_loc(location, EQ_EXPR, boolean_type_node, v, + fold_convert_loc(location, TREE_TYPE(v), + null_pointer_node)); + tree n = fold_convert_loc(location, TREE_TYPE(v1), null_pointer_node); + return fold_build3_loc(location, COND_EXPR, TREE_TYPE(v1), + eq, n, v1); +} + +// Return a tree for the conversion of an interface type to an +// interface type. + +tree +Expression::convert_interface_to_interface(Translate_context* context, + Type *lhs_type, Type *rhs_type, + tree rhs_tree, bool for_type_guard, + source_location location) +{ + Gogo* gogo = context->gogo(); + Interface_type* lhs_interface_type = lhs_type->interface_type(); + bool lhs_is_empty = lhs_interface_type->is_empty(); + + tree lhs_type_tree = lhs_type->get_tree(gogo); + if (lhs_type_tree == error_mark_node) + return error_mark_node; + + // In the general case this requires runtime examination of the type + // method table to match it up with the interface methods. + + // FIXME: If all of the methods in the right hand side interface + // also appear in the left hand side interface, then we don't need + // to do a runtime check, although we still need to build a new + // method table. + + // Get the type descriptor for the right hand side. This will be + // NULL for a nil interface. + + if (!DECL_P(rhs_tree)) + rhs_tree = save_expr(rhs_tree); + + tree rhs_type_descriptor = + Expression::get_interface_type_descriptor(context, rhs_type, rhs_tree, + location); + + // The result is going to be a two element constructor. + + VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 2); + + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + tree field = TYPE_FIELDS(lhs_type_tree); + elt->index = field; + + if (for_type_guard) + { + // A type assertion fails when converting a nil interface. + tree lhs_type_descriptor = lhs_type->type_descriptor_pointer(gogo); + static tree assert_interface_decl; + tree call = Gogo::call_builtin(&assert_interface_decl, + location, + "__go_assert_interface", + 2, + ptr_type_node, + TREE_TYPE(lhs_type_descriptor), + lhs_type_descriptor, + TREE_TYPE(rhs_type_descriptor), + rhs_type_descriptor); + if (call == error_mark_node) + return error_mark_node; + // This will panic if the interface conversion fails. + TREE_NOTHROW(assert_interface_decl) = 0; + elt->value = fold_convert_loc(location, TREE_TYPE(field), call); + } + else if (lhs_is_empty) + { + // A convertion to an empty interface always succeeds, and the + // first field is just the type descriptor of the object. + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), + "__type_descriptor") == 0); + gcc_assert(TREE_TYPE(field) == TREE_TYPE(rhs_type_descriptor)); + elt->value = rhs_type_descriptor; + } + else + { + // A conversion to a non-empty interface may fail, but unlike a + // type assertion converting nil will always succeed. + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__methods") + == 0); + tree lhs_type_descriptor = lhs_type->type_descriptor_pointer(gogo); + static tree convert_interface_decl; + tree call = Gogo::call_builtin(&convert_interface_decl, + location, + "__go_convert_interface", + 2, + ptr_type_node, + TREE_TYPE(lhs_type_descriptor), + lhs_type_descriptor, + TREE_TYPE(rhs_type_descriptor), + rhs_type_descriptor); + if (call == error_mark_node) + return error_mark_node; + // This will panic if the interface conversion fails. + TREE_NOTHROW(convert_interface_decl) = 0; + elt->value = fold_convert_loc(location, TREE_TYPE(field), call); + } + + // The second field is simply the object pointer. + + elt = VEC_quick_push(constructor_elt, init, NULL); + field = DECL_CHAIN(field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__object") == 0); + elt->index = field; + + tree rhs_type_tree = TREE_TYPE(rhs_tree); + gcc_assert(TREE_CODE(rhs_type_tree) == RECORD_TYPE); + tree rhs_field = DECL_CHAIN(TYPE_FIELDS(rhs_type_tree)); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(rhs_field)), "__object") == 0); + elt->value = build3(COMPONENT_REF, TREE_TYPE(rhs_field), rhs_tree, rhs_field, + NULL_TREE); + + return build_constructor(lhs_type_tree, init); +} + +// Return a tree for the conversion of an interface type to a +// non-interface type. + +tree +Expression::convert_interface_to_type(Translate_context* context, + Type *lhs_type, Type* rhs_type, + tree rhs_tree, source_location location) +{ + Gogo* gogo = context->gogo(); + tree rhs_type_tree = TREE_TYPE(rhs_tree); + + tree lhs_type_tree = lhs_type->get_tree(gogo); + if (lhs_type_tree == error_mark_node) + return error_mark_node; + + // Call a function to check that the type is valid. The function + // will panic with an appropriate runtime type error if the type is + // not valid. + + tree lhs_type_descriptor = lhs_type->type_descriptor_pointer(gogo); + + if (!DECL_P(rhs_tree)) + rhs_tree = save_expr(rhs_tree); + + tree rhs_type_descriptor = + Expression::get_interface_type_descriptor(context, rhs_type, rhs_tree, + location); + + tree rhs_inter_descriptor = rhs_type->type_descriptor_pointer(gogo); + + static tree check_interface_type_decl; + tree call = Gogo::call_builtin(&check_interface_type_decl, + location, + "__go_check_interface_type", + 3, + void_type_node, + TREE_TYPE(lhs_type_descriptor), + lhs_type_descriptor, + TREE_TYPE(rhs_type_descriptor), + rhs_type_descriptor, + TREE_TYPE(rhs_inter_descriptor), + rhs_inter_descriptor); + if (call == error_mark_node) + return error_mark_node; + // This call will panic if the conversion is invalid. + TREE_NOTHROW(check_interface_type_decl) = 0; + + // If the call succeeds, pull out the value. + gcc_assert(TREE_CODE(rhs_type_tree) == RECORD_TYPE); + tree rhs_field = DECL_CHAIN(TYPE_FIELDS(rhs_type_tree)); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(rhs_field)), "__object") == 0); + tree val = build3(COMPONENT_REF, TREE_TYPE(rhs_field), rhs_tree, rhs_field, + NULL_TREE); + + // If the value is a pointer, then it is the value we want. + // Otherwise it points to the value. + if (lhs_type->points_to() == NULL) + { + val = fold_convert_loc(location, build_pointer_type(lhs_type_tree), val); + val = build_fold_indirect_ref_loc(location, val); + } + + return build2(COMPOUND_EXPR, lhs_type_tree, call, + fold_convert_loc(location, lhs_type_tree, val)); +} + +// Convert an expression to a tree. This is implemented by the child +// class. Not that it is not in general safe to call this multiple +// times for a single expression, but that we don't catch such errors. + +tree +Expression::get_tree(Translate_context* context) +{ + // The child may have marked this expression as having an error. + if (this->classification_ == EXPRESSION_ERROR) + return error_mark_node; + + return this->do_get_tree(context); +} + +// Return a tree for VAL in TYPE. + +tree +Expression::integer_constant_tree(mpz_t val, tree type) +{ + if (type == error_mark_node) + return error_mark_node; + else if (TREE_CODE(type) == INTEGER_TYPE) + return double_int_to_tree(type, + mpz_get_double_int(type, val, true)); + else if (TREE_CODE(type) == REAL_TYPE) + { + mpfr_t fval; + mpfr_init_set_z(fval, val, GMP_RNDN); + tree ret = Expression::float_constant_tree(fval, type); + mpfr_clear(fval); + return ret; + } + else if (TREE_CODE(type) == COMPLEX_TYPE) + { + mpfr_t fval; + mpfr_init_set_z(fval, val, GMP_RNDN); + tree real = Expression::float_constant_tree(fval, TREE_TYPE(type)); + mpfr_clear(fval); + tree imag = build_real_from_int_cst(TREE_TYPE(type), + integer_zero_node); + return build_complex(type, real, imag); + } + else + gcc_unreachable(); +} + +// Return a tree for VAL in TYPE. + +tree +Expression::float_constant_tree(mpfr_t val, tree type) +{ + if (type == error_mark_node) + return error_mark_node; + else if (TREE_CODE(type) == INTEGER_TYPE) + { + mpz_t ival; + mpz_init(ival); + mpfr_get_z(ival, val, GMP_RNDN); + tree ret = Expression::integer_constant_tree(ival, type); + mpz_clear(ival); + return ret; + } + else if (TREE_CODE(type) == REAL_TYPE) + { + REAL_VALUE_TYPE r1; + real_from_mpfr(&r1, val, type, GMP_RNDN); + REAL_VALUE_TYPE r2; + real_convert(&r2, TYPE_MODE(type), &r1); + return build_real(type, r2); + } + else if (TREE_CODE(type) == COMPLEX_TYPE) + { + REAL_VALUE_TYPE r1; + real_from_mpfr(&r1, val, TREE_TYPE(type), GMP_RNDN); + REAL_VALUE_TYPE r2; + real_convert(&r2, TYPE_MODE(TREE_TYPE(type)), &r1); + tree imag = build_real_from_int_cst(TREE_TYPE(type), + integer_zero_node); + return build_complex(type, build_real(TREE_TYPE(type), r2), imag); + } + else + gcc_unreachable(); +} + +// Return a tree for REAL/IMAG in TYPE. + +tree +Expression::complex_constant_tree(mpfr_t real, mpfr_t imag, tree type) +{ + if (type == error_mark_node) + return error_mark_node; + else if (TREE_CODE(type) == INTEGER_TYPE || TREE_CODE(type) == REAL_TYPE) + return Expression::float_constant_tree(real, type); + else if (TREE_CODE(type) == COMPLEX_TYPE) + { + REAL_VALUE_TYPE r1; + real_from_mpfr(&r1, real, TREE_TYPE(type), GMP_RNDN); + REAL_VALUE_TYPE r2; + real_convert(&r2, TYPE_MODE(TREE_TYPE(type)), &r1); + + REAL_VALUE_TYPE r3; + real_from_mpfr(&r3, imag, TREE_TYPE(type), GMP_RNDN); + REAL_VALUE_TYPE r4; + real_convert(&r4, TYPE_MODE(TREE_TYPE(type)), &r3); + + return build_complex(type, build_real(TREE_TYPE(type), r2), + build_real(TREE_TYPE(type), r4)); + } + else + gcc_unreachable(); +} + +// Return a tree which evaluates to true if VAL, of arbitrary integer +// type, is negative or is more than the maximum value of BOUND_TYPE. +// If SOFAR is not NULL, it is or'red into the result. The return +// value may be NULL if SOFAR is NULL. + +tree +Expression::check_bounds(tree val, tree bound_type, tree sofar, + source_location loc) +{ + tree val_type = TREE_TYPE(val); + tree ret = NULL_TREE; + + if (!TYPE_UNSIGNED(val_type)) + { + ret = fold_build2_loc(loc, LT_EXPR, boolean_type_node, val, + build_int_cst(val_type, 0)); + if (ret == boolean_false_node) + ret = NULL_TREE; + } + + if ((TYPE_UNSIGNED(val_type) && !TYPE_UNSIGNED(bound_type)) + || TYPE_SIZE(val_type) > TYPE_SIZE(bound_type)) + { + tree max = TYPE_MAX_VALUE(bound_type); + tree big = fold_build2_loc(loc, GT_EXPR, boolean_type_node, val, + fold_convert_loc(loc, val_type, max)); + if (big == boolean_false_node) + ; + else if (ret == NULL_TREE) + ret = big; + else + ret = fold_build2_loc(loc, TRUTH_OR_EXPR, boolean_type_node, + ret, big); + } + + if (ret == NULL_TREE) + return sofar; + else if (sofar == NULL_TREE) + return ret; + else + return fold_build2_loc(loc, TRUTH_OR_EXPR, boolean_type_node, + sofar, ret); +} + +// Error expressions. This are used to avoid cascading errors. + +class Error_expression : public Expression +{ + public: + Error_expression(source_location location) + : Expression(EXPRESSION_ERROR, location) + { } + + protected: + bool + do_is_constant() const + { return true; } + + bool + do_integer_constant_value(bool, mpz_t val, Type**) const + { + mpz_set_ui(val, 0); + return true; + } + + bool + do_float_constant_value(mpfr_t val, Type**) const + { + mpfr_set_ui(val, 0, GMP_RNDN); + return true; + } + + bool + do_complex_constant_value(mpfr_t real, mpfr_t imag, Type**) const + { + mpfr_set_ui(real, 0, GMP_RNDN); + mpfr_set_ui(imag, 0, GMP_RNDN); + return true; + } + + void + do_discarding_value() + { } + + Type* + do_type() + { return Type::make_error_type(); } + + void + do_determine_type(const Type_context*) + { } + + Expression* + do_copy() + { return this; } + + bool + do_is_addressable() const + { return true; } + + tree + do_get_tree(Translate_context*) + { return error_mark_node; } +}; + +Expression* +Expression::make_error(source_location location) +{ + return new Error_expression(location); +} + +// An expression which is really a type. This is used during parsing. +// It is an error if these survive after lowering. + +class +Type_expression : public Expression +{ + public: + Type_expression(Type* type, source_location location) + : Expression(EXPRESSION_TYPE, location), + type_(type) + { } + + protected: + int + do_traverse(Traverse* traverse) + { return Type::traverse(this->type_, traverse); } + + Type* + do_type() + { return this->type_; } + + void + do_determine_type(const Type_context*) + { } + + void + do_check_types(Gogo*) + { this->report_error(_("invalid use of type")); } + + Expression* + do_copy() + { return this; } + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + // The type which we are representing as an expression. + Type* type_; +}; + +Expression* +Expression::make_type(Type* type, source_location location) +{ + return new Type_expression(type, location); +} + +// Class Parser_expression. + +Type* +Parser_expression::do_type() +{ + // We should never really ask for the type of a Parser_expression. + // However, it can happen, at least when we have an invalid const + // whose initializer refers to the const itself. In that case we + // may ask for the type when lowering the const itself. + gcc_assert(saw_errors()); + return Type::make_error_type(); +} + +// Class Var_expression. + +// Lower a variable expression. Here we just make sure that the +// initialization expression of the variable has been lowered. This +// ensures that we will be able to determine the type of the variable +// if necessary. + +Expression* +Var_expression::do_lower(Gogo* gogo, Named_object* function, int) +{ + if (this->variable_->is_variable()) + { + Variable* var = this->variable_->var_value(); + // This is either a local variable or a global variable. A + // reference to a variable which is local to an enclosing + // function will be a reference to a field in a closure. + if (var->is_global()) + function = NULL; + var->lower_init_expression(gogo, function); + } + return this; +} + +// Return the type of a reference to a variable. + +Type* +Var_expression::do_type() +{ + if (this->variable_->is_variable()) + return this->variable_->var_value()->type(); + else if (this->variable_->is_result_variable()) + return this->variable_->result_var_value()->type(); + else + gcc_unreachable(); +} + +// Determine the type of a reference to a variable. + +void +Var_expression::do_determine_type(const Type_context*) +{ + if (this->variable_->is_variable()) + this->variable_->var_value()->determine_type(); +} + +// Something takes the address of this variable. This means that we +// may want to move the variable onto the heap. + +void +Var_expression::do_address_taken(bool escapes) +{ + if (!escapes) + ; + else if (this->variable_->is_variable()) + this->variable_->var_value()->set_address_taken(); + else if (this->variable_->is_result_variable()) + this->variable_->result_var_value()->set_address_taken(); + else + gcc_unreachable(); +} + +// Get the tree for a reference to a variable. + +tree +Var_expression::do_get_tree(Translate_context* context) +{ + return this->variable_->get_tree(context->gogo(), context->function()); +} + +// Make a reference to a variable in an expression. + +Expression* +Expression::make_var_reference(Named_object* var, source_location location) +{ + if (var->is_sink()) + return Expression::make_sink(location); + + // FIXME: Creating a new object for each reference to a variable is + // wasteful. + return new Var_expression(var, location); +} + +// Class Temporary_reference_expression. + +// The type. + +Type* +Temporary_reference_expression::do_type() +{ + return this->statement_->type(); +} + +// Called if something takes the address of this temporary variable. +// We never have to move temporary variables to the heap, but we do +// need to know that they must live in the stack rather than in a +// register. + +void +Temporary_reference_expression::do_address_taken(bool) +{ + this->statement_->set_is_address_taken(); +} + +// Get a tree referring to the variable. + +tree +Temporary_reference_expression::do_get_tree(Translate_context*) +{ + return this->statement_->get_decl(); +} + +// Make a reference to a temporary variable. + +Expression* +Expression::make_temporary_reference(Temporary_statement* statement, + source_location location) +{ + return new Temporary_reference_expression(statement, location); +} + +// A sink expression--a use of the blank identifier _. + +class Sink_expression : public Expression +{ + public: + Sink_expression(source_location location) + : Expression(EXPRESSION_SINK, location), + type_(NULL), var_(NULL_TREE) + { } + + protected: + void + do_discarding_value() + { } + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + Expression* + do_copy() + { return new Sink_expression(this->location()); } + + tree + do_get_tree(Translate_context*); + + private: + // The type of this sink variable. + Type* type_; + // The temporary variable we generate. + tree var_; +}; + +// Return the type of a sink expression. + +Type* +Sink_expression::do_type() +{ + if (this->type_ == NULL) + return Type::make_sink_type(); + return this->type_; +} + +// Determine the type of a sink expression. + +void +Sink_expression::do_determine_type(const Type_context* context) +{ + if (context->type != NULL) + this->type_ = context->type; +} + +// Return a temporary variable for a sink expression. This will +// presumably be a write-only variable which the middle-end will drop. + +tree +Sink_expression::do_get_tree(Translate_context* context) +{ + if (this->var_ == NULL_TREE) + { + gcc_assert(this->type_ != NULL && !this->type_->is_sink_type()); + this->var_ = create_tmp_var(this->type_->get_tree(context->gogo()), + "blank"); + } + return this->var_; +} + +// Make a sink expression. + +Expression* +Expression::make_sink(source_location location) +{ + return new Sink_expression(location); +} + +// Class Func_expression. + +// FIXME: Can a function expression appear in a constant expression? +// The value is unchanging. Initializing a constant to the address of +// a function seems like it could work, though there might be little +// point to it. + +// Traversal. + +int +Func_expression::do_traverse(Traverse* traverse) +{ + return (this->closure_ == NULL + ? TRAVERSE_CONTINUE + : Expression::traverse(&this->closure_, traverse)); +} + +// Return the type of a function expression. + +Type* +Func_expression::do_type() +{ + if (this->function_->is_function()) + return this->function_->func_value()->type(); + else if (this->function_->is_function_declaration()) + return this->function_->func_declaration_value()->type(); + else + gcc_unreachable(); +} + +// Get the tree for a function expression without evaluating the +// closure. + +tree +Func_expression::get_tree_without_closure(Gogo* gogo) +{ + Function_type* fntype; + if (this->function_->is_function()) + fntype = this->function_->func_value()->type(); + else if (this->function_->is_function_declaration()) + fntype = this->function_->func_declaration_value()->type(); + else + gcc_unreachable(); + + // Builtin functions are handled specially by Call_expression. We + // can't take their address. + if (fntype->is_builtin()) + { + error_at(this->location(), "invalid use of special builtin function %qs", + this->function_->name().c_str()); + return error_mark_node; + } + + Named_object* no = this->function_; + + tree id = no->get_id(gogo); + if (id == error_mark_node) + return error_mark_node; + + tree fndecl; + if (no->is_function()) + fndecl = no->func_value()->get_or_make_decl(gogo, no, id); + else if (no->is_function_declaration()) + fndecl = no->func_declaration_value()->get_or_make_decl(gogo, no, id); + else + gcc_unreachable(); + + if (fndecl == error_mark_node) + return error_mark_node; + + return build_fold_addr_expr_loc(this->location(), fndecl); +} + +// Get the tree for a function expression. This is used when we take +// the address of a function rather than simply calling it. If the +// function has a closure, we must use a trampoline. + +tree +Func_expression::do_get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + + tree fnaddr = this->get_tree_without_closure(gogo); + if (fnaddr == error_mark_node) + return error_mark_node; + + gcc_assert(TREE_CODE(fnaddr) == ADDR_EXPR + && TREE_CODE(TREE_OPERAND(fnaddr, 0)) == FUNCTION_DECL); + TREE_ADDRESSABLE(TREE_OPERAND(fnaddr, 0)) = 1; + + // For a normal non-nested function call, that is all we have to do. + if (!this->function_->is_function() + || this->function_->func_value()->enclosing() == NULL) + { + gcc_assert(this->closure_ == NULL); + return fnaddr; + } + + // For a nested function call, we have to always allocate a + // trampoline. If we don't always allocate, then closures will not + // be reliably distinct. + Expression* closure = this->closure_; + tree closure_tree; + if (closure == NULL) + closure_tree = null_pointer_node; + else + { + // Get the value of the closure. This will be a pointer to + // space allocated on the heap. + closure_tree = closure->get_tree(context); + if (closure_tree == error_mark_node) + return error_mark_node; + gcc_assert(POINTER_TYPE_P(TREE_TYPE(closure_tree))); + } + + // Now we need to build some code on the heap. This code will load + // the static chain pointer with the closure and then jump to the + // body of the function. The normal gcc approach is to build the + // code on the stack. Unfortunately we can not do that, as Go + // permits us to return the function pointer. + + return gogo->make_trampoline(fnaddr, closure_tree, this->location()); +} + +// Make a reference to a function in an expression. + +Expression* +Expression::make_func_reference(Named_object* function, Expression* closure, + source_location location) +{ + return new Func_expression(function, closure, location); +} + +// Class Unknown_expression. + +// Return the name of an unknown expression. + +const std::string& +Unknown_expression::name() const +{ + return this->named_object_->name(); +} + +// Lower a reference to an unknown name. + +Expression* +Unknown_expression::do_lower(Gogo*, Named_object*, int) +{ + source_location location = this->location(); + Named_object* no = this->named_object_; + Named_object* real; + if (!no->is_unknown()) + real = no; + else + { + real = no->unknown_value()->real_named_object(); + if (real == NULL) + { + if (this->is_composite_literal_key_) + return this; + error_at(location, "reference to undefined name %qs", + this->named_object_->message_name().c_str()); + return Expression::make_error(location); + } + } + switch (real->classification()) + { + case Named_object::NAMED_OBJECT_CONST: + return Expression::make_const_reference(real, location); + case Named_object::NAMED_OBJECT_TYPE: + return Expression::make_type(real->type_value(), location); + case Named_object::NAMED_OBJECT_TYPE_DECLARATION: + if (this->is_composite_literal_key_) + return this; + error_at(location, "reference to undefined type %qs", + real->message_name().c_str()); + return Expression::make_error(location); + case Named_object::NAMED_OBJECT_VAR: + return Expression::make_var_reference(real, location); + case Named_object::NAMED_OBJECT_FUNC: + case Named_object::NAMED_OBJECT_FUNC_DECLARATION: + return Expression::make_func_reference(real, NULL, location); + case Named_object::NAMED_OBJECT_PACKAGE: + if (this->is_composite_literal_key_) + return this; + error_at(location, "unexpected reference to package"); + return Expression::make_error(location); + default: + gcc_unreachable(); + } +} + +// Make a reference to an unknown name. + +Expression* +Expression::make_unknown_reference(Named_object* no, source_location location) +{ + gcc_assert(no->resolve()->is_unknown()); + return new Unknown_expression(no, location); +} + +// A boolean expression. + +class Boolean_expression : public Expression +{ + public: + Boolean_expression(bool val, source_location location) + : Expression(EXPRESSION_BOOLEAN, location), + val_(val), type_(NULL) + { } + + static Expression* + do_import(Import*); + + protected: + bool + do_is_constant() const + { return true; } + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + Expression* + do_copy() + { return this; } + + tree + do_get_tree(Translate_context*) + { return this->val_ ? boolean_true_node : boolean_false_node; } + + void + do_export(Export* exp) const + { exp->write_c_string(this->val_ ? "true" : "false"); } + + private: + // The constant. + bool val_; + // The type as determined by context. + Type* type_; +}; + +// Get the type. + +Type* +Boolean_expression::do_type() +{ + if (this->type_ == NULL) + this->type_ = Type::make_boolean_type(); + return this->type_; +} + +// Set the type from the context. + +void +Boolean_expression::do_determine_type(const Type_context* context) +{ + if (this->type_ != NULL && !this->type_->is_abstract()) + ; + else if (context->type != NULL && context->type->is_boolean_type()) + this->type_ = context->type; + else if (!context->may_be_abstract) + this->type_ = Type::lookup_bool_type(); +} + +// Import a boolean constant. + +Expression* +Boolean_expression::do_import(Import* imp) +{ + if (imp->peek_char() == 't') + { + imp->require_c_string("true"); + return Expression::make_boolean(true, imp->location()); + } + else + { + imp->require_c_string("false"); + return Expression::make_boolean(false, imp->location()); + } +} + +// Make a boolean expression. + +Expression* +Expression::make_boolean(bool val, source_location location) +{ + return new Boolean_expression(val, location); +} + +// Class String_expression. + +// Get the type. + +Type* +String_expression::do_type() +{ + if (this->type_ == NULL) + this->type_ = Type::make_string_type(); + return this->type_; +} + +// Set the type from the context. + +void +String_expression::do_determine_type(const Type_context* context) +{ + if (this->type_ != NULL && !this->type_->is_abstract()) + ; + else if (context->type != NULL && context->type->is_string_type()) + this->type_ = context->type; + else if (!context->may_be_abstract) + this->type_ = Type::lookup_string_type(); +} + +// Build a string constant. + +tree +String_expression::do_get_tree(Translate_context* context) +{ + return context->gogo()->go_string_constant_tree(this->val_); +} + +// Export a string expression. + +void +String_expression::do_export(Export* exp) const +{ + std::string s; + s.reserve(this->val_.length() * 4 + 2); + s += '"'; + for (std::string::const_iterator p = this->val_.begin(); + p != this->val_.end(); + ++p) + { + if (*p == '\\' || *p == '"') + { + s += '\\'; + s += *p; + } + else if (*p >= 0x20 && *p < 0x7f) + s += *p; + else if (*p == '\n') + s += "\\n"; + else if (*p == '\t') + s += "\\t"; + else + { + s += "\\x"; + unsigned char c = *p; + unsigned int dig = c >> 4; + s += dig < 10 ? '0' + dig : 'A' + dig - 10; + dig = c & 0xf; + s += dig < 10 ? '0' + dig : 'A' + dig - 10; + } + } + s += '"'; + exp->write_string(s); +} + +// Import a string expression. + +Expression* +String_expression::do_import(Import* imp) +{ + imp->require_c_string("\""); + std::string val; + while (true) + { + int c = imp->get_char(); + if (c == '"' || c == -1) + break; + if (c != '\\') + val += static_cast<char>(c); + else + { + c = imp->get_char(); + if (c == '\\' || c == '"') + val += static_cast<char>(c); + else if (c == 'n') + val += '\n'; + else if (c == 't') + val += '\t'; + else if (c == 'x') + { + c = imp->get_char(); + unsigned int vh = c >= '0' && c <= '9' ? c - '0' : c - 'A' + 10; + c = imp->get_char(); + unsigned int vl = c >= '0' && c <= '9' ? c - '0' : c - 'A' + 10; + char v = (vh << 4) | vl; + val += v; + } + else + { + error_at(imp->location(), "bad string constant"); + return Expression::make_error(imp->location()); + } + } + } + return Expression::make_string(val, imp->location()); +} + +// Make a string expression. + +Expression* +Expression::make_string(const std::string& val, source_location location) +{ + return new String_expression(val, location); +} + +// Make an integer expression. + +class Integer_expression : public Expression +{ + public: + Integer_expression(const mpz_t* val, Type* type, source_location location) + : Expression(EXPRESSION_INTEGER, location), + type_(type) + { mpz_init_set(this->val_, *val); } + + static Expression* + do_import(Import*); + + // Return whether VAL fits in the type. + static bool + check_constant(mpz_t val, Type*, source_location); + + // Write VAL to export data. + static void + export_integer(Export* exp, const mpz_t val); + + protected: + bool + do_is_constant() const + { return true; } + + bool + do_integer_constant_value(bool, mpz_t val, Type** ptype) const; + + Type* + do_type(); + + void + do_determine_type(const Type_context* context); + + void + do_check_types(Gogo*); + + tree + do_get_tree(Translate_context*); + + Expression* + do_copy() + { return Expression::make_integer(&this->val_, this->type_, + this->location()); } + + void + do_export(Export*) const; + + private: + // The integer value. + mpz_t val_; + // The type so far. + Type* type_; +}; + +// Return an integer constant value. + +bool +Integer_expression::do_integer_constant_value(bool, mpz_t val, + Type** ptype) const +{ + if (this->type_ != NULL) + *ptype = this->type_; + mpz_set(val, this->val_); + return true; +} + +// Return the current type. If we haven't set the type yet, we return +// an abstract integer type. + +Type* +Integer_expression::do_type() +{ + if (this->type_ == NULL) + this->type_ = Type::make_abstract_integer_type(); + return this->type_; +} + +// Set the type of the integer value. Here we may switch from an +// abstract type to a real type. + +void +Integer_expression::do_determine_type(const Type_context* context) +{ + if (this->type_ != NULL && !this->type_->is_abstract()) + ; + else if (context->type != NULL + && (context->type->integer_type() != NULL + || context->type->float_type() != NULL + || context->type->complex_type() != NULL)) + this->type_ = context->type; + else if (!context->may_be_abstract) + this->type_ = Type::lookup_integer_type("int"); +} + +// Return true if the integer VAL fits in the range of the type TYPE. +// Otherwise give an error and return false. TYPE may be NULL. + +bool +Integer_expression::check_constant(mpz_t val, Type* type, + source_location location) +{ + if (type == NULL) + return true; + Integer_type* itype = type->integer_type(); + if (itype == NULL || itype->is_abstract()) + return true; + + int bits = mpz_sizeinbase(val, 2); + + if (itype->is_unsigned()) + { + // For an unsigned type we can only accept a nonnegative number, + // and we must be able to represent at least BITS. + if (mpz_sgn(val) >= 0 + && bits <= itype->bits()) + return true; + } + else + { + // For a signed type we need an extra bit to indicate the sign. + // We have to handle the most negative integer specially. + if (bits + 1 <= itype->bits() + || (bits <= itype->bits() + && mpz_sgn(val) < 0 + && (mpz_scan1(val, 0) + == static_cast<unsigned long>(itype->bits() - 1)) + && mpz_scan0(val, itype->bits()) == ULONG_MAX)) + return true; + } + + error_at(location, "integer constant overflow"); + return false; +} + +// Check the type of an integer constant. + +void +Integer_expression::do_check_types(Gogo*) +{ + if (this->type_ == NULL) + return; + if (!Integer_expression::check_constant(this->val_, this->type_, + this->location())) + this->set_is_error(); +} + +// Get a tree for an integer constant. + +tree +Integer_expression::do_get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + tree type; + if (this->type_ != NULL && !this->type_->is_abstract()) + type = this->type_->get_tree(gogo); + else if (this->type_ != NULL && this->type_->float_type() != NULL) + { + // We are converting to an abstract floating point type. + type = Type::lookup_float_type("float64")->get_tree(gogo); + } + else if (this->type_ != NULL && this->type_->complex_type() != NULL) + { + // We are converting to an abstract complex type. + type = Type::lookup_complex_type("complex128")->get_tree(gogo); + } + else + { + // If we still have an abstract type here, then this is being + // used in a constant expression which didn't get reduced for + // some reason. Use a type which will fit the value. We use <, + // not <=, because we need an extra bit for the sign bit. + int bits = mpz_sizeinbase(this->val_, 2); + if (bits < INT_TYPE_SIZE) + type = Type::lookup_integer_type("int")->get_tree(gogo); + else if (bits < 64) + type = Type::lookup_integer_type("int64")->get_tree(gogo); + else + type = long_long_integer_type_node; + } + return Expression::integer_constant_tree(this->val_, type); +} + +// Write VAL to export data. + +void +Integer_expression::export_integer(Export* exp, const mpz_t val) +{ + char* s = mpz_get_str(NULL, 10, val); + exp->write_c_string(s); + free(s); +} + +// Export an integer in a constant expression. + +void +Integer_expression::do_export(Export* exp) const +{ + Integer_expression::export_integer(exp, this->val_); + // A trailing space lets us reliably identify the end of the number. + exp->write_c_string(" "); +} + +// Import an integer, floating point, or complex value. This handles +// all these types because they all start with digits. + +Expression* +Integer_expression::do_import(Import* imp) +{ + std::string num = imp->read_identifier(); + imp->require_c_string(" "); + if (!num.empty() && num[num.length() - 1] == 'i') + { + mpfr_t real; + size_t plus_pos = num.find('+', 1); + size_t minus_pos = num.find('-', 1); + size_t pos; + if (plus_pos == std::string::npos) + pos = minus_pos; + else if (minus_pos == std::string::npos) + pos = plus_pos; + else + { + error_at(imp->location(), "bad number in import data: %qs", + num.c_str()); + return Expression::make_error(imp->location()); + } + if (pos == std::string::npos) + mpfr_set_ui(real, 0, GMP_RNDN); + else + { + std::string real_str = num.substr(0, pos); + if (mpfr_init_set_str(real, real_str.c_str(), 10, GMP_RNDN) != 0) + { + error_at(imp->location(), "bad number in import data: %qs", + real_str.c_str()); + return Expression::make_error(imp->location()); + } + } + + std::string imag_str; + if (pos == std::string::npos) + imag_str = num; + else + imag_str = num.substr(pos); + imag_str = imag_str.substr(0, imag_str.size() - 1); + mpfr_t imag; + if (mpfr_init_set_str(imag, imag_str.c_str(), 10, GMP_RNDN) != 0) + { + error_at(imp->location(), "bad number in import data: %qs", + imag_str.c_str()); + return Expression::make_error(imp->location()); + } + Expression* ret = Expression::make_complex(&real, &imag, NULL, + imp->location()); + mpfr_clear(real); + mpfr_clear(imag); + return ret; + } + else if (num.find('.') == std::string::npos + && num.find('E') == std::string::npos) + { + mpz_t val; + if (mpz_init_set_str(val, num.c_str(), 10) != 0) + { + error_at(imp->location(), "bad number in import data: %qs", + num.c_str()); + return Expression::make_error(imp->location()); + } + Expression* ret = Expression::make_integer(&val, NULL, imp->location()); + mpz_clear(val); + return ret; + } + else + { + mpfr_t val; + if (mpfr_init_set_str(val, num.c_str(), 10, GMP_RNDN) != 0) + { + error_at(imp->location(), "bad number in import data: %qs", + num.c_str()); + return Expression::make_error(imp->location()); + } + Expression* ret = Expression::make_float(&val, NULL, imp->location()); + mpfr_clear(val); + return ret; + } +} + +// Build a new integer value. + +Expression* +Expression::make_integer(const mpz_t* val, Type* type, + source_location location) +{ + return new Integer_expression(val, type, location); +} + +// Floats. + +class Float_expression : public Expression +{ + public: + Float_expression(const mpfr_t* val, Type* type, source_location location) + : Expression(EXPRESSION_FLOAT, location), + type_(type) + { + mpfr_init_set(this->val_, *val, GMP_RNDN); + } + + // Constrain VAL to fit into TYPE. + static void + constrain_float(mpfr_t val, Type* type); + + // Return whether VAL fits in the type. + static bool + check_constant(mpfr_t val, Type*, source_location); + + // Write VAL to export data. + static void + export_float(Export* exp, const mpfr_t val); + + protected: + bool + do_is_constant() const + { return true; } + + bool + do_float_constant_value(mpfr_t val, Type**) const; + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { return Expression::make_float(&this->val_, this->type_, + this->location()); } + + tree + do_get_tree(Translate_context*); + + void + do_export(Export*) const; + + private: + // The floating point value. + mpfr_t val_; + // The type so far. + Type* type_; +}; + +// Constrain VAL to fit into TYPE. + +void +Float_expression::constrain_float(mpfr_t val, Type* type) +{ + Float_type* ftype = type->float_type(); + if (ftype != NULL && !ftype->is_abstract()) + { + tree type_tree = ftype->type_tree(); + REAL_VALUE_TYPE rvt; + real_from_mpfr(&rvt, val, type_tree, GMP_RNDN); + real_convert(&rvt, TYPE_MODE(type_tree), &rvt); + mpfr_from_real(val, &rvt, GMP_RNDN); + } +} + +// Return a floating point constant value. + +bool +Float_expression::do_float_constant_value(mpfr_t val, Type** ptype) const +{ + if (this->type_ != NULL) + *ptype = this->type_; + mpfr_set(val, this->val_, GMP_RNDN); + return true; +} + +// Return the current type. If we haven't set the type yet, we return +// an abstract float type. + +Type* +Float_expression::do_type() +{ + if (this->type_ == NULL) + this->type_ = Type::make_abstract_float_type(); + return this->type_; +} + +// Set the type of the float value. Here we may switch from an +// abstract type to a real type. + +void +Float_expression::do_determine_type(const Type_context* context) +{ + if (this->type_ != NULL && !this->type_->is_abstract()) + ; + else if (context->type != NULL + && (context->type->integer_type() != NULL + || context->type->float_type() != NULL + || context->type->complex_type() != NULL)) + this->type_ = context->type; + else if (!context->may_be_abstract) + this->type_ = Type::lookup_float_type("float64"); +} + +// Return true if the floating point value VAL fits in the range of +// the type TYPE. Otherwise give an error and return false. TYPE may +// be NULL. + +bool +Float_expression::check_constant(mpfr_t val, Type* type, + source_location location) +{ + if (type == NULL) + return true; + Float_type* ftype = type->float_type(); + if (ftype == NULL || ftype->is_abstract()) + return true; + + // A NaN or Infinity always fits in the range of the type. + if (mpfr_nan_p(val) || mpfr_inf_p(val) || mpfr_zero_p(val)) + return true; + + mp_exp_t exp = mpfr_get_exp(val); + mp_exp_t max_exp; + switch (ftype->bits()) + { + case 32: + max_exp = 128; + break; + case 64: + max_exp = 1024; + break; + default: + gcc_unreachable(); + } + if (exp > max_exp) + { + error_at(location, "floating point constant overflow"); + return false; + } + return true; +} + +// Check the type of a float value. + +void +Float_expression::do_check_types(Gogo*) +{ + if (this->type_ == NULL) + return; + + if (!Float_expression::check_constant(this->val_, this->type_, + this->location())) + this->set_is_error(); + + Integer_type* integer_type = this->type_->integer_type(); + if (integer_type != NULL) + { + if (!mpfr_integer_p(this->val_)) + this->report_error(_("floating point constant truncated to integer")); + else + { + gcc_assert(!integer_type->is_abstract()); + mpz_t ival; + mpz_init(ival); + mpfr_get_z(ival, this->val_, GMP_RNDN); + Integer_expression::check_constant(ival, integer_type, + this->location()); + mpz_clear(ival); + } + } +} + +// Get a tree for a float constant. + +tree +Float_expression::do_get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + tree type; + if (this->type_ != NULL && !this->type_->is_abstract()) + type = this->type_->get_tree(gogo); + else if (this->type_ != NULL && this->type_->integer_type() != NULL) + { + // We have an abstract integer type. We just hope for the best. + type = Type::lookup_integer_type("int")->get_tree(gogo); + } + else + { + // If we still have an abstract type here, then this is being + // used in a constant expression which didn't get reduced. We + // just use float64 and hope for the best. + type = Type::lookup_float_type("float64")->get_tree(gogo); + } + return Expression::float_constant_tree(this->val_, type); +} + +// Write a floating point number to export data. + +void +Float_expression::export_float(Export *exp, const mpfr_t val) +{ + mp_exp_t exponent; + char* s = mpfr_get_str(NULL, &exponent, 10, 0, val, GMP_RNDN); + if (*s == '-') + exp->write_c_string("-"); + exp->write_c_string("0."); + exp->write_c_string(*s == '-' ? s + 1 : s); + mpfr_free_str(s); + char buf[30]; + snprintf(buf, sizeof buf, "E%ld", exponent); + exp->write_c_string(buf); +} + +// Export a floating point number in a constant expression. + +void +Float_expression::do_export(Export* exp) const +{ + Float_expression::export_float(exp, this->val_); + // A trailing space lets us reliably identify the end of the number. + exp->write_c_string(" "); +} + +// Make a float expression. + +Expression* +Expression::make_float(const mpfr_t* val, Type* type, source_location location) +{ + return new Float_expression(val, type, location); +} + +// Complex numbers. + +class Complex_expression : public Expression +{ + public: + Complex_expression(const mpfr_t* real, const mpfr_t* imag, Type* type, + source_location location) + : Expression(EXPRESSION_COMPLEX, location), + type_(type) + { + mpfr_init_set(this->real_, *real, GMP_RNDN); + mpfr_init_set(this->imag_, *imag, GMP_RNDN); + } + + // Constrain REAL/IMAG to fit into TYPE. + static void + constrain_complex(mpfr_t real, mpfr_t imag, Type* type); + + // Return whether REAL/IMAG fits in the type. + static bool + check_constant(mpfr_t real, mpfr_t imag, Type*, source_location); + + // Write REAL/IMAG to export data. + static void + export_complex(Export* exp, const mpfr_t real, const mpfr_t val); + + protected: + bool + do_is_constant() const + { return true; } + + bool + do_complex_constant_value(mpfr_t real, mpfr_t imag, Type**) const; + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return Expression::make_complex(&this->real_, &this->imag_, this->type_, + this->location()); + } + + tree + do_get_tree(Translate_context*); + + void + do_export(Export*) const; + + private: + // The real part. + mpfr_t real_; + // The imaginary part; + mpfr_t imag_; + // The type if known. + Type* type_; +}; + +// Constrain REAL/IMAG to fit into TYPE. + +void +Complex_expression::constrain_complex(mpfr_t real, mpfr_t imag, Type* type) +{ + Complex_type* ctype = type->complex_type(); + if (ctype != NULL && !ctype->is_abstract()) + { + tree type_tree = ctype->type_tree(); + + REAL_VALUE_TYPE rvt; + real_from_mpfr(&rvt, real, TREE_TYPE(type_tree), GMP_RNDN); + real_convert(&rvt, TYPE_MODE(TREE_TYPE(type_tree)), &rvt); + mpfr_from_real(real, &rvt, GMP_RNDN); + + real_from_mpfr(&rvt, imag, TREE_TYPE(type_tree), GMP_RNDN); + real_convert(&rvt, TYPE_MODE(TREE_TYPE(type_tree)), &rvt); + mpfr_from_real(imag, &rvt, GMP_RNDN); + } +} + +// Return a complex constant value. + +bool +Complex_expression::do_complex_constant_value(mpfr_t real, mpfr_t imag, + Type** ptype) const +{ + if (this->type_ != NULL) + *ptype = this->type_; + mpfr_set(real, this->real_, GMP_RNDN); + mpfr_set(imag, this->imag_, GMP_RNDN); + return true; +} + +// Return the current type. If we haven't set the type yet, we return +// an abstract complex type. + +Type* +Complex_expression::do_type() +{ + if (this->type_ == NULL) + this->type_ = Type::make_abstract_complex_type(); + return this->type_; +} + +// Set the type of the complex value. Here we may switch from an +// abstract type to a real type. + +void +Complex_expression::do_determine_type(const Type_context* context) +{ + if (this->type_ != NULL && !this->type_->is_abstract()) + ; + else if (context->type != NULL + && context->type->complex_type() != NULL) + this->type_ = context->type; + else if (!context->may_be_abstract) + this->type_ = Type::lookup_complex_type("complex128"); +} + +// Return true if the complex value REAL/IMAG fits in the range of the +// type TYPE. Otherwise give an error and return false. TYPE may be +// NULL. + +bool +Complex_expression::check_constant(mpfr_t real, mpfr_t imag, Type* type, + source_location location) +{ + if (type == NULL) + return true; + Complex_type* ctype = type->complex_type(); + if (ctype == NULL || ctype->is_abstract()) + return true; + + mp_exp_t max_exp; + switch (ctype->bits()) + { + case 64: + max_exp = 128; + break; + case 128: + max_exp = 1024; + break; + default: + gcc_unreachable(); + } + + // A NaN or Infinity always fits in the range of the type. + if (!mpfr_nan_p(real) && !mpfr_inf_p(real) && !mpfr_zero_p(real)) + { + if (mpfr_get_exp(real) > max_exp) + { + error_at(location, "complex real part constant overflow"); + return false; + } + } + + if (!mpfr_nan_p(imag) && !mpfr_inf_p(imag) && !mpfr_zero_p(imag)) + { + if (mpfr_get_exp(imag) > max_exp) + { + error_at(location, "complex imaginary part constant overflow"); + return false; + } + } + + return true; +} + +// Check the type of a complex value. + +void +Complex_expression::do_check_types(Gogo*) +{ + if (this->type_ == NULL) + return; + + if (!Complex_expression::check_constant(this->real_, this->imag_, + this->type_, this->location())) + this->set_is_error(); +} + +// Get a tree for a complex constant. + +tree +Complex_expression::do_get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + tree type; + if (this->type_ != NULL && !this->type_->is_abstract()) + type = this->type_->get_tree(gogo); + else + { + // If we still have an abstract type here, this this is being + // used in a constant expression which didn't get reduced. We + // just use complex128 and hope for the best. + type = Type::lookup_complex_type("complex128")->get_tree(gogo); + } + return Expression::complex_constant_tree(this->real_, this->imag_, type); +} + +// Write REAL/IMAG to export data. + +void +Complex_expression::export_complex(Export* exp, const mpfr_t real, + const mpfr_t imag) +{ + if (!mpfr_zero_p(real)) + { + Float_expression::export_float(exp, real); + if (mpfr_sgn(imag) > 0) + exp->write_c_string("+"); + } + Float_expression::export_float(exp, imag); + exp->write_c_string("i"); +} + +// Export a complex number in a constant expression. + +void +Complex_expression::do_export(Export* exp) const +{ + Complex_expression::export_complex(exp, this->real_, this->imag_); + // A trailing space lets us reliably identify the end of the number. + exp->write_c_string(" "); +} + +// Make a complex expression. + +Expression* +Expression::make_complex(const mpfr_t* real, const mpfr_t* imag, Type* type, + source_location location) +{ + return new Complex_expression(real, imag, type, location); +} + +// Find a named object in an expression. + +class Find_named_object : public Traverse +{ + public: + Find_named_object(Named_object* no) + : Traverse(traverse_expressions), + no_(no), found_(false) + { } + + // Whether we found the object. + bool + found() const + { return this->found_; } + + protected: + int + expression(Expression**); + + private: + // The object we are looking for. + Named_object* no_; + // Whether we found it. + bool found_; +}; + +// A reference to a const in an expression. + +class Const_expression : public Expression +{ + public: + Const_expression(Named_object* constant, source_location location) + : Expression(EXPRESSION_CONST_REFERENCE, location), + constant_(constant), type_(NULL), seen_(false) + { } + + Named_object* + named_object() + { return this->constant_; } + + // Check that the initializer does not refer to the constant itself. + void + check_for_init_loop(); + + protected: + int + do_traverse(Traverse*); + + Expression* + do_lower(Gogo*, Named_object*, int); + + bool + do_is_constant() const + { return true; } + + bool + do_integer_constant_value(bool, mpz_t val, Type**) const; + + bool + do_float_constant_value(mpfr_t val, Type**) const; + + bool + do_complex_constant_value(mpfr_t real, mpfr_t imag, Type**) const; + + bool + do_string_constant_value(std::string* val) const + { return this->constant_->const_value()->expr()->string_constant_value(val); } + + Type* + do_type(); + + // The type of a const is set by the declaration, not the use. + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { return this; } + + tree + do_get_tree(Translate_context* context); + + // When exporting a reference to a const as part of a const + // expression, we export the value. We ignore the fact that it has + // a name. + void + do_export(Export* exp) const + { this->constant_->const_value()->expr()->export_expression(exp); } + + private: + // The constant. + Named_object* constant_; + // The type of this reference. This is used if the constant has an + // abstract type. + Type* type_; + // Used to prevent infinite recursion when a constant incorrectly + // refers to itself. + mutable bool seen_; +}; + +// Traversal. + +int +Const_expression::do_traverse(Traverse* traverse) +{ + if (this->type_ != NULL) + return Type::traverse(this->type_, traverse); + return TRAVERSE_CONTINUE; +} + +// Lower a constant expression. This is where we convert the +// predeclared constant iota into an integer value. + +Expression* +Const_expression::do_lower(Gogo* gogo, Named_object*, int iota_value) +{ + if (this->constant_->const_value()->expr()->classification() + == EXPRESSION_IOTA) + { + if (iota_value == -1) + { + error_at(this->location(), + "iota is only defined in const declarations"); + iota_value = 0; + } + mpz_t val; + mpz_init_set_ui(val, static_cast<unsigned long>(iota_value)); + Expression* ret = Expression::make_integer(&val, NULL, + this->location()); + mpz_clear(val); + return ret; + } + + // Make sure that the constant itself has been lowered. + gogo->lower_constant(this->constant_); + + return this; +} + +// Return an integer constant value. + +bool +Const_expression::do_integer_constant_value(bool iota_is_constant, mpz_t val, + Type** ptype) const +{ + if (this->seen_) + return false; + + Type* ctype; + if (this->type_ != NULL) + ctype = this->type_; + else + ctype = this->constant_->const_value()->type(); + if (ctype != NULL && ctype->integer_type() == NULL) + return false; + + Expression* e = this->constant_->const_value()->expr(); + + this->seen_ = true; + + Type* t; + bool r = e->integer_constant_value(iota_is_constant, val, &t); + + this->seen_ = false; + + if (r + && ctype != NULL + && !Integer_expression::check_constant(val, ctype, this->location())) + return false; + + *ptype = ctype != NULL ? ctype : t; + return r; +} + +// Return a floating point constant value. + +bool +Const_expression::do_float_constant_value(mpfr_t val, Type** ptype) const +{ + if (this->seen_) + return false; + + Type* ctype; + if (this->type_ != NULL) + ctype = this->type_; + else + ctype = this->constant_->const_value()->type(); + if (ctype != NULL && ctype->float_type() == NULL) + return false; + + this->seen_ = true; + + Type* t; + bool r = this->constant_->const_value()->expr()->float_constant_value(val, + &t); + + this->seen_ = false; + + if (r && ctype != NULL) + { + if (!Float_expression::check_constant(val, ctype, this->location())) + return false; + Float_expression::constrain_float(val, ctype); + } + *ptype = ctype != NULL ? ctype : t; + return r; +} + +// Return a complex constant value. + +bool +Const_expression::do_complex_constant_value(mpfr_t real, mpfr_t imag, + Type **ptype) const +{ + if (this->seen_) + return false; + + Type* ctype; + if (this->type_ != NULL) + ctype = this->type_; + else + ctype = this->constant_->const_value()->type(); + if (ctype != NULL && ctype->complex_type() == NULL) + return false; + + this->seen_ = true; + + Type *t; + bool r = this->constant_->const_value()->expr()->complex_constant_value(real, + imag, + &t); + + this->seen_ = false; + + if (r && ctype != NULL) + { + if (!Complex_expression::check_constant(real, imag, ctype, + this->location())) + return false; + Complex_expression::constrain_complex(real, imag, ctype); + } + *ptype = ctype != NULL ? ctype : t; + return r; +} + +// Return the type of the const reference. + +Type* +Const_expression::do_type() +{ + if (this->type_ != NULL) + return this->type_; + + Named_constant* nc = this->constant_->const_value(); + + if (this->seen_ || nc->lowering()) + { + this->report_error(_("constant refers to itself")); + this->type_ = Type::make_error_type(); + return this->type_; + } + + this->seen_ = true; + + Type* ret = nc->type(); + + if (ret != NULL) + { + this->seen_ = false; + return ret; + } + + // During parsing, a named constant may have a NULL type, but we + // must not return a NULL type here. + ret = nc->expr()->type(); + + this->seen_ = false; + + return ret; +} + +// Set the type of the const reference. + +void +Const_expression::do_determine_type(const Type_context* context) +{ + Type* ctype = this->constant_->const_value()->type(); + Type* cetype = (ctype != NULL + ? ctype + : this->constant_->const_value()->expr()->type()); + if (ctype != NULL && !ctype->is_abstract()) + ; + else if (context->type != NULL + && (context->type->integer_type() != NULL + || context->type->float_type() != NULL + || context->type->complex_type() != NULL) + && (cetype->integer_type() != NULL + || cetype->float_type() != NULL + || cetype->complex_type() != NULL)) + this->type_ = context->type; + else if (context->type != NULL + && context->type->is_string_type() + && cetype->is_string_type()) + this->type_ = context->type; + else if (context->type != NULL + && context->type->is_boolean_type() + && cetype->is_boolean_type()) + this->type_ = context->type; + else if (!context->may_be_abstract) + { + if (cetype->is_abstract()) + cetype = cetype->make_non_abstract_type(); + this->type_ = cetype; + } +} + +// Check for a loop in which the initializer of a constant refers to +// the constant itself. + +void +Const_expression::check_for_init_loop() +{ + if (this->type_ != NULL && this->type_->is_error_type()) + return; + + if (this->seen_) + { + this->report_error(_("constant refers to itself")); + this->type_ = Type::make_error_type(); + return; + } + + Expression* init = this->constant_->const_value()->expr(); + Find_named_object find_named_object(this->constant_); + + this->seen_ = true; + Expression::traverse(&init, &find_named_object); + this->seen_ = false; + + if (find_named_object.found()) + { + if (this->type_ == NULL || !this->type_->is_error_type()) + { + this->report_error(_("constant refers to itself")); + this->type_ = Type::make_error_type(); + } + return; + } +} + +// Check types of a const reference. + +void +Const_expression::do_check_types(Gogo*) +{ + if (this->type_ != NULL && this->type_->is_error_type()) + return; + + this->check_for_init_loop(); + + if (this->type_ == NULL || this->type_->is_abstract()) + return; + + // Check for integer overflow. + if (this->type_->integer_type() != NULL) + { + mpz_t ival; + mpz_init(ival); + Type* dummy; + if (!this->integer_constant_value(true, ival, &dummy)) + { + mpfr_t fval; + mpfr_init(fval); + Expression* cexpr = this->constant_->const_value()->expr(); + if (cexpr->float_constant_value(fval, &dummy)) + { + if (!mpfr_integer_p(fval)) + this->report_error(_("floating point constant " + "truncated to integer")); + else + { + mpfr_get_z(ival, fval, GMP_RNDN); + Integer_expression::check_constant(ival, this->type_, + this->location()); + } + } + mpfr_clear(fval); + } + mpz_clear(ival); + } +} + +// Return a tree for the const reference. + +tree +Const_expression::do_get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + tree type_tree; + if (this->type_ == NULL) + type_tree = NULL_TREE; + else + { + type_tree = this->type_->get_tree(gogo); + if (type_tree == error_mark_node) + return error_mark_node; + } + + // If the type has been set for this expression, but the underlying + // object is an abstract int or float, we try to get the abstract + // value. Otherwise we may lose something in the conversion. + if (this->type_ != NULL + && (this->constant_->const_value()->type() == NULL + || this->constant_->const_value()->type()->is_abstract())) + { + Expression* expr = this->constant_->const_value()->expr(); + mpz_t ival; + mpz_init(ival); + Type* t; + if (expr->integer_constant_value(true, ival, &t)) + { + tree ret = Expression::integer_constant_tree(ival, type_tree); + mpz_clear(ival); + return ret; + } + mpz_clear(ival); + + mpfr_t fval; + mpfr_init(fval); + if (expr->float_constant_value(fval, &t)) + { + tree ret = Expression::float_constant_tree(fval, type_tree); + mpfr_clear(fval); + return ret; + } + + mpfr_t imag; + mpfr_init(imag); + if (expr->complex_constant_value(fval, imag, &t)) + { + tree ret = Expression::complex_constant_tree(fval, imag, type_tree); + mpfr_clear(fval); + mpfr_clear(imag); + return ret; + } + mpfr_clear(imag); + mpfr_clear(fval); + } + + tree const_tree = this->constant_->get_tree(gogo, context->function()); + if (this->type_ == NULL + || const_tree == error_mark_node + || TREE_TYPE(const_tree) == error_mark_node) + return const_tree; + + tree ret; + if (TYPE_MAIN_VARIANT(type_tree) == TYPE_MAIN_VARIANT(TREE_TYPE(const_tree))) + ret = fold_convert(type_tree, const_tree); + else if (TREE_CODE(type_tree) == INTEGER_TYPE) + ret = fold(convert_to_integer(type_tree, const_tree)); + else if (TREE_CODE(type_tree) == REAL_TYPE) + ret = fold(convert_to_real(type_tree, const_tree)); + else if (TREE_CODE(type_tree) == COMPLEX_TYPE) + ret = fold(convert_to_complex(type_tree, const_tree)); + else + gcc_unreachable(); + return ret; +} + +// Make a reference to a constant in an expression. + +Expression* +Expression::make_const_reference(Named_object* constant, + source_location location) +{ + return new Const_expression(constant, location); +} + +// Find a named object in an expression. + +int +Find_named_object::expression(Expression** pexpr) +{ + switch ((*pexpr)->classification()) + { + case Expression::EXPRESSION_CONST_REFERENCE: + { + Const_expression* ce = static_cast<Const_expression*>(*pexpr); + if (ce->named_object() == this->no_) + break; + + // We need to check a constant initializer explicitly, as + // loops here will not be caught by the loop checking for + // variable initializers. + ce->check_for_init_loop(); + + return TRAVERSE_CONTINUE; + } + + case Expression::EXPRESSION_VAR_REFERENCE: + if ((*pexpr)->var_expression()->named_object() == this->no_) + break; + return TRAVERSE_CONTINUE; + case Expression::EXPRESSION_FUNC_REFERENCE: + if ((*pexpr)->func_expression()->named_object() == this->no_) + break; + return TRAVERSE_CONTINUE; + default: + return TRAVERSE_CONTINUE; + } + this->found_ = true; + return TRAVERSE_EXIT; +} + +// The nil value. + +class Nil_expression : public Expression +{ + public: + Nil_expression(source_location location) + : Expression(EXPRESSION_NIL, location) + { } + + static Expression* + do_import(Import*); + + protected: + bool + do_is_constant() const + { return true; } + + Type* + do_type() + { return Type::make_nil_type(); } + + void + do_determine_type(const Type_context*) + { } + + Expression* + do_copy() + { return this; } + + tree + do_get_tree(Translate_context*) + { return null_pointer_node; } + + void + do_export(Export* exp) const + { exp->write_c_string("nil"); } +}; + +// Import a nil expression. + +Expression* +Nil_expression::do_import(Import* imp) +{ + imp->require_c_string("nil"); + return Expression::make_nil(imp->location()); +} + +// Make a nil expression. + +Expression* +Expression::make_nil(source_location location) +{ + return new Nil_expression(location); +} + +// The value of the predeclared constant iota. This is little more +// than a marker. This will be lowered to an integer in +// Const_expression::do_lower, which is where we know the value that +// it should have. + +class Iota_expression : public Parser_expression +{ + public: + Iota_expression(source_location location) + : Parser_expression(EXPRESSION_IOTA, location) + { } + + protected: + Expression* + do_lower(Gogo*, Named_object*, int) + { gcc_unreachable(); } + + // There should only ever be one of these. + Expression* + do_copy() + { gcc_unreachable(); } +}; + +// Make an iota expression. This is only called for one case: the +// value of the predeclared constant iota. + +Expression* +Expression::make_iota() +{ + static Iota_expression iota_expression(UNKNOWN_LOCATION); + return &iota_expression; +} + +// A type conversion expression. + +class Type_conversion_expression : public Expression +{ + public: + Type_conversion_expression(Type* type, Expression* expr, + source_location location) + : Expression(EXPRESSION_CONVERSION, location), + type_(type), expr_(expr), may_convert_function_types_(false) + { } + + // Return the type to which we are converting. + Type* + type() const + { return this->type_; } + + // Return the expression which we are converting. + Expression* + expr() const + { return this->expr_; } + + // Permit converting from one function type to another. This is + // used internally for method expressions. + void + set_may_convert_function_types() + { + this->may_convert_function_types_ = true; + } + + // Import a type conversion expression. + static Expression* + do_import(Import*); + + protected: + int + do_traverse(Traverse* traverse); + + Expression* + do_lower(Gogo*, Named_object*, int); + + bool + do_is_constant() const + { return this->expr_->is_constant(); } + + bool + do_integer_constant_value(bool, mpz_t, Type**) const; + + bool + do_float_constant_value(mpfr_t, Type**) const; + + bool + do_complex_constant_value(mpfr_t, mpfr_t, Type**) const; + + bool + do_string_constant_value(std::string*) const; + + Type* + do_type() + { return this->type_; } + + void + do_determine_type(const Type_context*) + { + Type_context subcontext(this->type_, false); + this->expr_->determine_type(&subcontext); + } + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return new Type_conversion_expression(this->type_, this->expr_->copy(), + this->location()); + } + + tree + do_get_tree(Translate_context* context); + + void + do_export(Export*) const; + + private: + // The type to convert to. + Type* type_; + // The expression to convert. + Expression* expr_; + // True if this is permitted to convert function types. This is + // used internally for method expressions. + bool may_convert_function_types_; +}; + +// Traversal. + +int +Type_conversion_expression::do_traverse(Traverse* traverse) +{ + if (Expression::traverse(&this->expr_, traverse) == TRAVERSE_EXIT + || Type::traverse(this->type_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Convert to a constant at lowering time. + +Expression* +Type_conversion_expression::do_lower(Gogo*, Named_object*, int) +{ + Type* type = this->type_; + Expression* val = this->expr_; + source_location location = this->location(); + + if (type->integer_type() != NULL) + { + mpz_t ival; + mpz_init(ival); + Type* dummy; + if (val->integer_constant_value(false, ival, &dummy)) + { + if (!Integer_expression::check_constant(ival, type, location)) + mpz_set_ui(ival, 0); + Expression* ret = Expression::make_integer(&ival, type, location); + mpz_clear(ival); + return ret; + } + + mpfr_t fval; + mpfr_init(fval); + if (val->float_constant_value(fval, &dummy)) + { + if (!mpfr_integer_p(fval)) + { + error_at(location, + "floating point constant truncated to integer"); + return Expression::make_error(location); + } + mpfr_get_z(ival, fval, GMP_RNDN); + if (!Integer_expression::check_constant(ival, type, location)) + mpz_set_ui(ival, 0); + Expression* ret = Expression::make_integer(&ival, type, location); + mpfr_clear(fval); + mpz_clear(ival); + return ret; + } + mpfr_clear(fval); + mpz_clear(ival); + } + + if (type->float_type() != NULL) + { + mpfr_t fval; + mpfr_init(fval); + Type* dummy; + if (val->float_constant_value(fval, &dummy)) + { + if (!Float_expression::check_constant(fval, type, location)) + mpfr_set_ui(fval, 0, GMP_RNDN); + Float_expression::constrain_float(fval, type); + Expression *ret = Expression::make_float(&fval, type, location); + mpfr_clear(fval); + return ret; + } + mpfr_clear(fval); + } + + if (type->complex_type() != NULL) + { + mpfr_t real; + mpfr_t imag; + mpfr_init(real); + mpfr_init(imag); + Type* dummy; + if (val->complex_constant_value(real, imag, &dummy)) + { + if (!Complex_expression::check_constant(real, imag, type, location)) + { + mpfr_set_ui(real, 0, GMP_RNDN); + mpfr_set_ui(imag, 0, GMP_RNDN); + } + Complex_expression::constrain_complex(real, imag, type); + Expression* ret = Expression::make_complex(&real, &imag, type, + location); + mpfr_clear(real); + mpfr_clear(imag); + return ret; + } + mpfr_clear(real); + mpfr_clear(imag); + } + + if (type->is_open_array_type() && type->named_type() == NULL) + { + Type* element_type = type->array_type()->element_type()->forwarded(); + bool is_byte = element_type == Type::lookup_integer_type("uint8"); + bool is_int = element_type == Type::lookup_integer_type("int"); + if (is_byte || is_int) + { + std::string s; + if (val->string_constant_value(&s)) + { + Expression_list* vals = new Expression_list(); + if (is_byte) + { + for (std::string::const_iterator p = s.begin(); + p != s.end(); + p++) + { + mpz_t val; + mpz_init_set_ui(val, static_cast<unsigned char>(*p)); + Expression* v = Expression::make_integer(&val, + element_type, + location); + vals->push_back(v); + mpz_clear(val); + } + } + else + { + const char *p = s.data(); + const char *pend = s.data() + s.length(); + while (p < pend) + { + unsigned int c; + int adv = Lex::fetch_char(p, &c); + if (adv == 0) + { + warning_at(this->location(), 0, + "invalid UTF-8 encoding"); + adv = 1; + } + p += adv; + mpz_t val; + mpz_init_set_ui(val, c); + Expression* v = Expression::make_integer(&val, + element_type, + location); + vals->push_back(v); + mpz_clear(val); + } + } + + return Expression::make_slice_composite_literal(type, vals, + location); + } + } + } + + return this; +} + +// Return the constant integer value if there is one. + +bool +Type_conversion_expression::do_integer_constant_value(bool iota_is_constant, + mpz_t val, + Type** ptype) const +{ + if (this->type_->integer_type() == NULL) + return false; + + mpz_t ival; + mpz_init(ival); + Type* dummy; + if (this->expr_->integer_constant_value(iota_is_constant, ival, &dummy)) + { + if (!Integer_expression::check_constant(ival, this->type_, + this->location())) + { + mpz_clear(ival); + return false; + } + mpz_set(val, ival); + mpz_clear(ival); + *ptype = this->type_; + return true; + } + mpz_clear(ival); + + mpfr_t fval; + mpfr_init(fval); + if (this->expr_->float_constant_value(fval, &dummy)) + { + mpfr_get_z(val, fval, GMP_RNDN); + mpfr_clear(fval); + if (!Integer_expression::check_constant(val, this->type_, + this->location())) + return false; + *ptype = this->type_; + return true; + } + mpfr_clear(fval); + + return false; +} + +// Return the constant floating point value if there is one. + +bool +Type_conversion_expression::do_float_constant_value(mpfr_t val, + Type** ptype) const +{ + if (this->type_->float_type() == NULL) + return false; + + mpfr_t fval; + mpfr_init(fval); + Type* dummy; + if (this->expr_->float_constant_value(fval, &dummy)) + { + if (!Float_expression::check_constant(fval, this->type_, + this->location())) + { + mpfr_clear(fval); + return false; + } + mpfr_set(val, fval, GMP_RNDN); + mpfr_clear(fval); + Float_expression::constrain_float(val, this->type_); + *ptype = this->type_; + return true; + } + mpfr_clear(fval); + + return false; +} + +// Return the constant complex value if there is one. + +bool +Type_conversion_expression::do_complex_constant_value(mpfr_t real, + mpfr_t imag, + Type **ptype) const +{ + if (this->type_->complex_type() == NULL) + return false; + + mpfr_t rval; + mpfr_t ival; + mpfr_init(rval); + mpfr_init(ival); + Type* dummy; + if (this->expr_->complex_constant_value(rval, ival, &dummy)) + { + if (!Complex_expression::check_constant(rval, ival, this->type_, + this->location())) + { + mpfr_clear(rval); + mpfr_clear(ival); + return false; + } + mpfr_set(real, rval, GMP_RNDN); + mpfr_set(imag, ival, GMP_RNDN); + mpfr_clear(rval); + mpfr_clear(ival); + Complex_expression::constrain_complex(real, imag, this->type_); + *ptype = this->type_; + return true; + } + mpfr_clear(rval); + mpfr_clear(ival); + + return false; +} + +// Return the constant string value if there is one. + +bool +Type_conversion_expression::do_string_constant_value(std::string* val) const +{ + if (this->type_->is_string_type() + && this->expr_->type()->integer_type() != NULL) + { + mpz_t ival; + mpz_init(ival); + Type* dummy; + if (this->expr_->integer_constant_value(false, ival, &dummy)) + { + unsigned long ulval = mpz_get_ui(ival); + if (mpz_cmp_ui(ival, ulval) == 0) + { + Lex::append_char(ulval, true, val, this->location()); + mpz_clear(ival); + return true; + } + } + mpz_clear(ival); + } + + // FIXME: Could handle conversion from const []int here. + + return false; +} + +// Check that types are convertible. + +void +Type_conversion_expression::do_check_types(Gogo*) +{ + Type* type = this->type_; + Type* expr_type = this->expr_->type(); + std::string reason; + + if (type->is_error_type() + || type->is_undefined() + || expr_type->is_error_type() + || expr_type->is_undefined()) + { + // Make sure we emit an error for an undefined type. + type->base(); + expr_type->base(); + this->set_is_error(); + return; + } + + if (this->may_convert_function_types_ + && type->function_type() != NULL + && expr_type->function_type() != NULL) + return; + + if (Type::are_convertible(type, expr_type, &reason)) + return; + + error_at(this->location(), "%s", reason.c_str()); + this->set_is_error(); +} + +// Get a tree for a type conversion. + +tree +Type_conversion_expression::do_get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + tree type_tree = this->type_->get_tree(gogo); + tree expr_tree = this->expr_->get_tree(context); + + if (type_tree == error_mark_node + || expr_tree == error_mark_node + || TREE_TYPE(expr_tree) == error_mark_node) + return error_mark_node; + + if (TYPE_MAIN_VARIANT(type_tree) == TYPE_MAIN_VARIANT(TREE_TYPE(expr_tree))) + return fold_convert(type_tree, expr_tree); + + Type* type = this->type_; + Type* expr_type = this->expr_->type(); + tree ret; + if (type->interface_type() != NULL || expr_type->interface_type() != NULL) + ret = Expression::convert_for_assignment(context, type, expr_type, + expr_tree, this->location()); + else if (type->integer_type() != NULL) + { + if (expr_type->integer_type() != NULL + || expr_type->float_type() != NULL + || expr_type->is_unsafe_pointer_type()) + ret = fold(convert_to_integer(type_tree, expr_tree)); + else + gcc_unreachable(); + } + else if (type->float_type() != NULL) + { + if (expr_type->integer_type() != NULL + || expr_type->float_type() != NULL) + ret = fold(convert_to_real(type_tree, expr_tree)); + else + gcc_unreachable(); + } + else if (type->complex_type() != NULL) + { + if (expr_type->complex_type() != NULL) + ret = fold(convert_to_complex(type_tree, expr_tree)); + else + gcc_unreachable(); + } + else if (type->is_string_type() + && expr_type->integer_type() != NULL) + { + expr_tree = fold_convert(integer_type_node, expr_tree); + if (host_integerp(expr_tree, 0)) + { + HOST_WIDE_INT intval = tree_low_cst(expr_tree, 0); + std::string s; + Lex::append_char(intval, true, &s, this->location()); + Expression* se = Expression::make_string(s, this->location()); + return se->get_tree(context); + } + + static tree int_to_string_fndecl; + ret = Gogo::call_builtin(&int_to_string_fndecl, + this->location(), + "__go_int_to_string", + 1, + type_tree, + integer_type_node, + fold_convert(integer_type_node, expr_tree)); + } + else if (type->is_string_type() + && (expr_type->array_type() != NULL + || (expr_type->points_to() != NULL + && expr_type->points_to()->array_type() != NULL))) + { + Type* t = expr_type; + if (t->points_to() != NULL) + { + t = t->points_to(); + expr_tree = build_fold_indirect_ref(expr_tree); + } + if (!DECL_P(expr_tree)) + expr_tree = save_expr(expr_tree); + Array_type* a = t->array_type(); + Type* e = a->element_type()->forwarded(); + gcc_assert(e->integer_type() != NULL); + tree valptr = fold_convert(const_ptr_type_node, + a->value_pointer_tree(gogo, expr_tree)); + tree len = a->length_tree(gogo, expr_tree); + len = fold_convert_loc(this->location(), size_type_node, len); + if (e->integer_type()->is_unsigned() + && e->integer_type()->bits() == 8) + { + static tree byte_array_to_string_fndecl; + ret = Gogo::call_builtin(&byte_array_to_string_fndecl, + this->location(), + "__go_byte_array_to_string", + 2, + type_tree, + const_ptr_type_node, + valptr, + size_type_node, + len); + } + else + { + gcc_assert(e == Type::lookup_integer_type("int")); + static tree int_array_to_string_fndecl; + ret = Gogo::call_builtin(&int_array_to_string_fndecl, + this->location(), + "__go_int_array_to_string", + 2, + type_tree, + const_ptr_type_node, + valptr, + size_type_node, + len); + } + } + else if (type->is_open_array_type() && expr_type->is_string_type()) + { + Type* e = type->array_type()->element_type()->forwarded(); + gcc_assert(e->integer_type() != NULL); + if (e->integer_type()->is_unsigned() + && e->integer_type()->bits() == 8) + { + static tree string_to_byte_array_fndecl; + ret = Gogo::call_builtin(&string_to_byte_array_fndecl, + this->location(), + "__go_string_to_byte_array", + 1, + type_tree, + TREE_TYPE(expr_tree), + expr_tree); + } + else + { + gcc_assert(e == Type::lookup_integer_type("int")); + static tree string_to_int_array_fndecl; + ret = Gogo::call_builtin(&string_to_int_array_fndecl, + this->location(), + "__go_string_to_int_array", + 1, + type_tree, + TREE_TYPE(expr_tree), + expr_tree); + } + } + else if ((type->is_unsafe_pointer_type() + && expr_type->points_to() != NULL) + || (expr_type->is_unsafe_pointer_type() + && type->points_to() != NULL)) + ret = fold_convert(type_tree, expr_tree); + else if (type->is_unsafe_pointer_type() + && expr_type->integer_type() != NULL) + ret = convert_to_pointer(type_tree, expr_tree); + else if (this->may_convert_function_types_ + && type->function_type() != NULL + && expr_type->function_type() != NULL) + ret = fold_convert_loc(this->location(), type_tree, expr_tree); + else + ret = Expression::convert_for_assignment(context, type, expr_type, + expr_tree, this->location()); + + return ret; +} + +// Output a type conversion in a constant expression. + +void +Type_conversion_expression::do_export(Export* exp) const +{ + exp->write_c_string("convert("); + exp->write_type(this->type_); + exp->write_c_string(", "); + this->expr_->export_expression(exp); + exp->write_c_string(")"); +} + +// Import a type conversion or a struct construction. + +Expression* +Type_conversion_expression::do_import(Import* imp) +{ + imp->require_c_string("convert("); + Type* type = imp->read_type(); + imp->require_c_string(", "); + Expression* val = Expression::import_expression(imp); + imp->require_c_string(")"); + return Expression::make_cast(type, val, imp->location()); +} + +// Make a type cast expression. + +Expression* +Expression::make_cast(Type* type, Expression* val, source_location location) +{ + if (type->is_error_type() || val->is_error_expression()) + return Expression::make_error(location); + return new Type_conversion_expression(type, val, location); +} + +// Unary expressions. + +class Unary_expression : public Expression +{ + public: + Unary_expression(Operator op, Expression* expr, source_location location) + : Expression(EXPRESSION_UNARY, location), + op_(op), escapes_(true), expr_(expr) + { } + + // Return the operator. + Operator + op() const + { return this->op_; } + + // Return the operand. + Expression* + operand() const + { return this->expr_; } + + // Record that an address expression does not escape. + void + set_does_not_escape() + { + gcc_assert(this->op_ == OPERATOR_AND); + this->escapes_ = false; + } + + // Apply unary opcode OP to UVAL, setting VAL. Return true if this + // could be done, false if not. + static bool + eval_integer(Operator op, Type* utype, mpz_t uval, mpz_t val, + source_location); + + // Apply unary opcode OP to UVAL, setting VAL. Return true if this + // could be done, false if not. + static bool + eval_float(Operator op, mpfr_t uval, mpfr_t val); + + // Apply unary opcode OP to UREAL/UIMAG, setting REAL/IMAG. Return + // true if this could be done, false if not. + static bool + eval_complex(Operator op, mpfr_t ureal, mpfr_t uimag, mpfr_t real, + mpfr_t imag); + + static Expression* + do_import(Import*); + + protected: + int + do_traverse(Traverse* traverse) + { return Expression::traverse(&this->expr_, traverse); } + + Expression* + do_lower(Gogo*, Named_object*, int); + + bool + do_is_constant() const; + + bool + do_integer_constant_value(bool, mpz_t, Type**) const; + + bool + do_float_constant_value(mpfr_t, Type**) const; + + bool + do_complex_constant_value(mpfr_t, mpfr_t, Type**) const; + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return Expression::make_unary(this->op_, this->expr_->copy(), + this->location()); + } + + bool + do_is_addressable() const + { return this->op_ == OPERATOR_MULT; } + + tree + do_get_tree(Translate_context*); + + void + do_export(Export*) const; + + private: + // The unary operator to apply. + Operator op_; + // Normally true. False if this is an address expression which does + // not escape the current function. + bool escapes_; + // The operand. + Expression* expr_; +}; + +// If we are taking the address of a composite literal, and the +// contents are not constant, then we want to make a heap composite +// instead. + +Expression* +Unary_expression::do_lower(Gogo*, Named_object*, int) +{ + source_location loc = this->location(); + Operator op = this->op_; + Expression* expr = this->expr_; + + if (op == OPERATOR_MULT && expr->is_type_expression()) + return Expression::make_type(Type::make_pointer_type(expr->type()), loc); + + // *&x simplifies to x. *(*T)(unsafe.Pointer)(&x) does not require + // moving x to the heap. FIXME: Is it worth doing a real escape + // analysis here? This case is found in math/unsafe.go and is + // therefore worth special casing. + if (op == OPERATOR_MULT) + { + Expression* e = expr; + while (e->classification() == EXPRESSION_CONVERSION) + { + Type_conversion_expression* te + = static_cast<Type_conversion_expression*>(e); + e = te->expr(); + } + + if (e->classification() == EXPRESSION_UNARY) + { + Unary_expression* ue = static_cast<Unary_expression*>(e); + if (ue->op_ == OPERATOR_AND) + { + if (e == expr) + { + // *&x == x. + return ue->expr_; + } + ue->set_does_not_escape(); + } + } + } + + if (op == OPERATOR_PLUS || op == OPERATOR_MINUS + || op == OPERATOR_NOT || op == OPERATOR_XOR) + { + Expression* ret = NULL; + + mpz_t eval; + mpz_init(eval); + Type* etype; + if (expr->integer_constant_value(false, eval, &etype)) + { + mpz_t val; + mpz_init(val); + if (Unary_expression::eval_integer(op, etype, eval, val, loc)) + ret = Expression::make_integer(&val, etype, loc); + mpz_clear(val); + } + mpz_clear(eval); + if (ret != NULL) + return ret; + + if (op == OPERATOR_PLUS || op == OPERATOR_MINUS) + { + mpfr_t fval; + mpfr_init(fval); + Type* ftype; + if (expr->float_constant_value(fval, &ftype)) + { + mpfr_t val; + mpfr_init(val); + if (Unary_expression::eval_float(op, fval, val)) + ret = Expression::make_float(&val, ftype, loc); + mpfr_clear(val); + } + if (ret != NULL) + { + mpfr_clear(fval); + return ret; + } + + mpfr_t ival; + mpfr_init(ival); + if (expr->complex_constant_value(fval, ival, &ftype)) + { + mpfr_t real; + mpfr_t imag; + mpfr_init(real); + mpfr_init(imag); + if (Unary_expression::eval_complex(op, fval, ival, real, imag)) + ret = Expression::make_complex(&real, &imag, ftype, loc); + mpfr_clear(real); + mpfr_clear(imag); + } + mpfr_clear(ival); + mpfr_clear(fval); + if (ret != NULL) + return ret; + } + } + + return this; +} + +// Return whether a unary expression is a constant. + +bool +Unary_expression::do_is_constant() const +{ + if (this->op_ == OPERATOR_MULT) + { + // Indirecting through a pointer is only constant if the object + // to which the expression points is constant, but we currently + // have no way to determine that. + return false; + } + else if (this->op_ == OPERATOR_AND) + { + // Taking the address of a variable is constant if it is a + // global variable, not constant otherwise. In other cases + // taking the address is probably not a constant. + Var_expression* ve = this->expr_->var_expression(); + if (ve != NULL) + { + Named_object* no = ve->named_object(); + return no->is_variable() && no->var_value()->is_global(); + } + return false; + } + else + return this->expr_->is_constant(); +} + +// Apply unary opcode OP to UVAL, setting VAL. UTYPE is the type of +// UVAL, if known; it may be NULL. Return true if this could be done, +// false if not. + +bool +Unary_expression::eval_integer(Operator op, Type* utype, mpz_t uval, mpz_t val, + source_location location) +{ + switch (op) + { + case OPERATOR_PLUS: + mpz_set(val, uval); + return true; + case OPERATOR_MINUS: + mpz_neg(val, uval); + return Integer_expression::check_constant(val, utype, location); + case OPERATOR_NOT: + mpz_set_ui(val, mpz_cmp_si(uval, 0) == 0 ? 1 : 0); + return true; + case OPERATOR_XOR: + if (utype == NULL + || utype->integer_type() == NULL + || utype->integer_type()->is_abstract()) + mpz_com(val, uval); + else + { + // The number of HOST_WIDE_INTs that it takes to represent + // UVAL. + size_t count = ((mpz_sizeinbase(uval, 2) + + HOST_BITS_PER_WIDE_INT + - 1) + / HOST_BITS_PER_WIDE_INT); + + unsigned HOST_WIDE_INT* phwi = new unsigned HOST_WIDE_INT[count]; + memset(phwi, 0, count * sizeof(HOST_WIDE_INT)); + + size_t ecount; + mpz_export(phwi, &ecount, -1, sizeof(HOST_WIDE_INT), 0, 0, uval); + gcc_assert(ecount <= count); + + // Trim down to the number of words required by the type. + size_t obits = utype->integer_type()->bits(); + if (!utype->integer_type()->is_unsigned()) + ++obits; + size_t ocount = ((obits + HOST_BITS_PER_WIDE_INT - 1) + / HOST_BITS_PER_WIDE_INT); + gcc_assert(ocount <= ocount); + + for (size_t i = 0; i < ocount; ++i) + phwi[i] = ~phwi[i]; + + size_t clearbits = ocount * HOST_BITS_PER_WIDE_INT - obits; + if (clearbits != 0) + phwi[ocount - 1] &= (((unsigned HOST_WIDE_INT) (HOST_WIDE_INT) -1) + >> clearbits); + + mpz_import(val, ocount, -1, sizeof(HOST_WIDE_INT), 0, 0, phwi); + + delete[] phwi; + } + return Integer_expression::check_constant(val, utype, location); + case OPERATOR_AND: + case OPERATOR_MULT: + return false; + default: + gcc_unreachable(); + } +} + +// Apply unary opcode OP to UVAL, setting VAL. Return true if this +// could be done, false if not. + +bool +Unary_expression::eval_float(Operator op, mpfr_t uval, mpfr_t val) +{ + switch (op) + { + case OPERATOR_PLUS: + mpfr_set(val, uval, GMP_RNDN); + return true; + case OPERATOR_MINUS: + mpfr_neg(val, uval, GMP_RNDN); + return true; + case OPERATOR_NOT: + case OPERATOR_XOR: + case OPERATOR_AND: + case OPERATOR_MULT: + return false; + default: + gcc_unreachable(); + } +} + +// Apply unary opcode OP to RVAL/IVAL, setting REAL/IMAG. Return true +// if this could be done, false if not. + +bool +Unary_expression::eval_complex(Operator op, mpfr_t rval, mpfr_t ival, + mpfr_t real, mpfr_t imag) +{ + switch (op) + { + case OPERATOR_PLUS: + mpfr_set(real, rval, GMP_RNDN); + mpfr_set(imag, ival, GMP_RNDN); + return true; + case OPERATOR_MINUS: + mpfr_neg(real, rval, GMP_RNDN); + mpfr_neg(imag, ival, GMP_RNDN); + return true; + case OPERATOR_NOT: + case OPERATOR_XOR: + case OPERATOR_AND: + case OPERATOR_MULT: + return false; + default: + gcc_unreachable(); + } +} + +// Return the integral constant value of a unary expression, if it has one. + +bool +Unary_expression::do_integer_constant_value(bool iota_is_constant, mpz_t val, + Type** ptype) const +{ + mpz_t uval; + mpz_init(uval); + bool ret; + if (!this->expr_->integer_constant_value(iota_is_constant, uval, ptype)) + ret = false; + else + ret = Unary_expression::eval_integer(this->op_, *ptype, uval, val, + this->location()); + mpz_clear(uval); + return ret; +} + +// Return the floating point constant value of a unary expression, if +// it has one. + +bool +Unary_expression::do_float_constant_value(mpfr_t val, Type** ptype) const +{ + mpfr_t uval; + mpfr_init(uval); + bool ret; + if (!this->expr_->float_constant_value(uval, ptype)) + ret = false; + else + ret = Unary_expression::eval_float(this->op_, uval, val); + mpfr_clear(uval); + return ret; +} + +// Return the complex constant value of a unary expression, if it has +// one. + +bool +Unary_expression::do_complex_constant_value(mpfr_t real, mpfr_t imag, + Type** ptype) const +{ + mpfr_t rval; + mpfr_t ival; + mpfr_init(rval); + mpfr_init(ival); + bool ret; + if (!this->expr_->complex_constant_value(rval, ival, ptype)) + ret = false; + else + ret = Unary_expression::eval_complex(this->op_, rval, ival, real, imag); + mpfr_clear(rval); + mpfr_clear(ival); + return ret; +} + +// Return the type of a unary expression. + +Type* +Unary_expression::do_type() +{ + switch (this->op_) + { + case OPERATOR_PLUS: + case OPERATOR_MINUS: + case OPERATOR_NOT: + case OPERATOR_XOR: + return this->expr_->type(); + + case OPERATOR_AND: + return Type::make_pointer_type(this->expr_->type()); + + case OPERATOR_MULT: + { + Type* subtype = this->expr_->type(); + Type* points_to = subtype->points_to(); + if (points_to == NULL) + return Type::make_error_type(); + return points_to; + } + + default: + gcc_unreachable(); + } +} + +// Determine abstract types for a unary expression. + +void +Unary_expression::do_determine_type(const Type_context* context) +{ + switch (this->op_) + { + case OPERATOR_PLUS: + case OPERATOR_MINUS: + case OPERATOR_NOT: + case OPERATOR_XOR: + this->expr_->determine_type(context); + break; + + case OPERATOR_AND: + // Taking the address of something. + { + Type* subtype = (context->type == NULL + ? NULL + : context->type->points_to()); + Type_context subcontext(subtype, false); + this->expr_->determine_type(&subcontext); + } + break; + + case OPERATOR_MULT: + // Indirecting through a pointer. + { + Type* subtype = (context->type == NULL + ? NULL + : Type::make_pointer_type(context->type)); + Type_context subcontext(subtype, false); + this->expr_->determine_type(&subcontext); + } + break; + + default: + gcc_unreachable(); + } +} + +// Check types for a unary expression. + +void +Unary_expression::do_check_types(Gogo*) +{ + Type* type = this->expr_->type(); + if (type->is_error_type()) + { + this->set_is_error(); + return; + } + + switch (this->op_) + { + case OPERATOR_PLUS: + case OPERATOR_MINUS: + if (type->integer_type() == NULL + && type->float_type() == NULL + && type->complex_type() == NULL) + this->report_error(_("expected numeric type")); + break; + + case OPERATOR_NOT: + case OPERATOR_XOR: + if (type->integer_type() == NULL + && !type->is_boolean_type()) + this->report_error(_("expected integer or boolean type")); + break; + + case OPERATOR_AND: + if (!this->expr_->is_addressable()) + this->report_error(_("invalid operand for unary %<&%>")); + else + this->expr_->address_taken(this->escapes_); + break; + + case OPERATOR_MULT: + // Indirecting through a pointer. + if (type->points_to() == NULL) + this->report_error(_("expected pointer")); + break; + + default: + gcc_unreachable(); + } +} + +// Get a tree for a unary expression. + +tree +Unary_expression::do_get_tree(Translate_context* context) +{ + tree expr = this->expr_->get_tree(context); + if (expr == error_mark_node) + return error_mark_node; + + source_location loc = this->location(); + switch (this->op_) + { + case OPERATOR_PLUS: + return expr; + + case OPERATOR_MINUS: + { + tree type = TREE_TYPE(expr); + tree compute_type = excess_precision_type(type); + if (compute_type != NULL_TREE) + expr = ::convert(compute_type, expr); + tree ret = fold_build1_loc(loc, NEGATE_EXPR, + (compute_type != NULL_TREE + ? compute_type + : type), + expr); + if (compute_type != NULL_TREE) + ret = ::convert(type, ret); + return ret; + } + + case OPERATOR_NOT: + if (TREE_CODE(TREE_TYPE(expr)) == BOOLEAN_TYPE) + return fold_build1_loc(loc, TRUTH_NOT_EXPR, TREE_TYPE(expr), expr); + else + return fold_build2_loc(loc, NE_EXPR, boolean_type_node, expr, + build_int_cst(TREE_TYPE(expr), 0)); + + case OPERATOR_XOR: + return fold_build1_loc(loc, BIT_NOT_EXPR, TREE_TYPE(expr), expr); + + case OPERATOR_AND: + // We should not see a non-constant constructor here; cases + // where we would see one should have been moved onto the heap + // at parse time. Taking the address of a nonconstant + // constructor will not do what the programmer expects. + gcc_assert(TREE_CODE(expr) != CONSTRUCTOR || TREE_CONSTANT(expr)); + gcc_assert(TREE_CODE(expr) != ADDR_EXPR); + + // Build a decl for a constant constructor. + if (TREE_CODE(expr) == CONSTRUCTOR && TREE_CONSTANT(expr)) + { + tree decl = build_decl(this->location(), VAR_DECL, + create_tmp_var_name("C"), TREE_TYPE(expr)); + DECL_EXTERNAL(decl) = 0; + TREE_PUBLIC(decl) = 0; + TREE_READONLY(decl) = 1; + TREE_CONSTANT(decl) = 1; + TREE_STATIC(decl) = 1; + TREE_ADDRESSABLE(decl) = 1; + DECL_ARTIFICIAL(decl) = 1; + DECL_INITIAL(decl) = expr; + rest_of_decl_compilation(decl, 1, 0); + expr = decl; + } + + return build_fold_addr_expr_loc(loc, expr); + + case OPERATOR_MULT: + { + gcc_assert(POINTER_TYPE_P(TREE_TYPE(expr))); + + // If we are dereferencing the pointer to a large struct, we + // need to check for nil. We don't bother to check for small + // structs because we expect the system to crash on a nil + // pointer dereference. + HOST_WIDE_INT s = int_size_in_bytes(TREE_TYPE(TREE_TYPE(expr))); + if (s == -1 || s >= 4096) + { + if (!DECL_P(expr)) + expr = save_expr(expr); + tree compare = fold_build2_loc(loc, EQ_EXPR, boolean_type_node, + expr, + fold_convert(TREE_TYPE(expr), + null_pointer_node)); + tree crash = Gogo::runtime_error(RUNTIME_ERROR_NIL_DEREFERENCE, + loc); + expr = fold_build2_loc(loc, COMPOUND_EXPR, TREE_TYPE(expr), + build3(COND_EXPR, void_type_node, + compare, crash, NULL_TREE), + expr); + } + + // If the type of EXPR is a recursive pointer type, then we + // need to insert a cast before indirecting. + if (TREE_TYPE(TREE_TYPE(expr)) == ptr_type_node) + { + Type* pt = this->expr_->type()->points_to(); + tree ind = pt->get_tree(context->gogo()); + expr = fold_convert_loc(loc, build_pointer_type(ind), expr); + } + + return build_fold_indirect_ref_loc(loc, expr); + } + + default: + gcc_unreachable(); + } +} + +// Export a unary expression. + +void +Unary_expression::do_export(Export* exp) const +{ + switch (this->op_) + { + case OPERATOR_PLUS: + exp->write_c_string("+ "); + break; + case OPERATOR_MINUS: + exp->write_c_string("- "); + break; + case OPERATOR_NOT: + exp->write_c_string("! "); + break; + case OPERATOR_XOR: + exp->write_c_string("^ "); + break; + case OPERATOR_AND: + case OPERATOR_MULT: + default: + gcc_unreachable(); + } + this->expr_->export_expression(exp); +} + +// Import a unary expression. + +Expression* +Unary_expression::do_import(Import* imp) +{ + Operator op; + switch (imp->get_char()) + { + case '+': + op = OPERATOR_PLUS; + break; + case '-': + op = OPERATOR_MINUS; + break; + case '!': + op = OPERATOR_NOT; + break; + case '^': + op = OPERATOR_XOR; + break; + default: + gcc_unreachable(); + } + imp->require_c_string(" "); + Expression* expr = Expression::import_expression(imp); + return Expression::make_unary(op, expr, imp->location()); +} + +// Make a unary expression. + +Expression* +Expression::make_unary(Operator op, Expression* expr, source_location location) +{ + return new Unary_expression(op, expr, location); +} + +// If this is an indirection through a pointer, return the expression +// being pointed through. Otherwise return this. + +Expression* +Expression::deref() +{ + if (this->classification_ == EXPRESSION_UNARY) + { + Unary_expression* ue = static_cast<Unary_expression*>(this); + if (ue->op() == OPERATOR_MULT) + return ue->operand(); + } + return this; +} + +// Class Binary_expression. + +// Traversal. + +int +Binary_expression::do_traverse(Traverse* traverse) +{ + int t = Expression::traverse(&this->left_, traverse); + if (t == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return Expression::traverse(&this->right_, traverse); +} + +// Compare integer constants according to OP. + +bool +Binary_expression::compare_integer(Operator op, mpz_t left_val, + mpz_t right_val) +{ + int i = mpz_cmp(left_val, right_val); + switch (op) + { + case OPERATOR_EQEQ: + return i == 0; + case OPERATOR_NOTEQ: + return i != 0; + case OPERATOR_LT: + return i < 0; + case OPERATOR_LE: + return i <= 0; + case OPERATOR_GT: + return i > 0; + case OPERATOR_GE: + return i >= 0; + default: + gcc_unreachable(); + } +} + +// Compare floating point constants according to OP. + +bool +Binary_expression::compare_float(Operator op, Type* type, mpfr_t left_val, + mpfr_t right_val) +{ + int i; + if (type == NULL) + i = mpfr_cmp(left_val, right_val); + else + { + mpfr_t lv; + mpfr_init_set(lv, left_val, GMP_RNDN); + mpfr_t rv; + mpfr_init_set(rv, right_val, GMP_RNDN); + Float_expression::constrain_float(lv, type); + Float_expression::constrain_float(rv, type); + i = mpfr_cmp(lv, rv); + mpfr_clear(lv); + mpfr_clear(rv); + } + switch (op) + { + case OPERATOR_EQEQ: + return i == 0; + case OPERATOR_NOTEQ: + return i != 0; + case OPERATOR_LT: + return i < 0; + case OPERATOR_LE: + return i <= 0; + case OPERATOR_GT: + return i > 0; + case OPERATOR_GE: + return i >= 0; + default: + gcc_unreachable(); + } +} + +// Compare complex constants according to OP. Complex numbers may +// only be compared for equality. + +bool +Binary_expression::compare_complex(Operator op, Type* type, + mpfr_t left_real, mpfr_t left_imag, + mpfr_t right_real, mpfr_t right_imag) +{ + bool is_equal; + if (type == NULL) + is_equal = (mpfr_cmp(left_real, right_real) == 0 + && mpfr_cmp(left_imag, right_imag) == 0); + else + { + mpfr_t lr; + mpfr_t li; + mpfr_init_set(lr, left_real, GMP_RNDN); + mpfr_init_set(li, left_imag, GMP_RNDN); + mpfr_t rr; + mpfr_t ri; + mpfr_init_set(rr, right_real, GMP_RNDN); + mpfr_init_set(ri, right_imag, GMP_RNDN); + Complex_expression::constrain_complex(lr, li, type); + Complex_expression::constrain_complex(rr, ri, type); + is_equal = mpfr_cmp(lr, rr) == 0 && mpfr_cmp(li, ri) == 0; + mpfr_clear(lr); + mpfr_clear(li); + mpfr_clear(rr); + mpfr_clear(ri); + } + switch (op) + { + case OPERATOR_EQEQ: + return is_equal; + case OPERATOR_NOTEQ: + return !is_equal; + default: + gcc_unreachable(); + } +} + +// Apply binary opcode OP to LEFT_VAL and RIGHT_VAL, setting VAL. +// LEFT_TYPE is the type of LEFT_VAL, RIGHT_TYPE is the type of +// RIGHT_VAL; LEFT_TYPE and/or RIGHT_TYPE may be NULL. Return true if +// this could be done, false if not. + +bool +Binary_expression::eval_integer(Operator op, Type* left_type, mpz_t left_val, + Type* right_type, mpz_t right_val, + source_location location, mpz_t val) +{ + bool is_shift_op = false; + switch (op) + { + case OPERATOR_OROR: + case OPERATOR_ANDAND: + case OPERATOR_EQEQ: + case OPERATOR_NOTEQ: + case OPERATOR_LT: + case OPERATOR_LE: + case OPERATOR_GT: + case OPERATOR_GE: + // These return boolean values. We should probably handle them + // anyhow in case a type conversion is used on the result. + return false; + case OPERATOR_PLUS: + mpz_add(val, left_val, right_val); + break; + case OPERATOR_MINUS: + mpz_sub(val, left_val, right_val); + break; + case OPERATOR_OR: + mpz_ior(val, left_val, right_val); + break; + case OPERATOR_XOR: + mpz_xor(val, left_val, right_val); + break; + case OPERATOR_MULT: + mpz_mul(val, left_val, right_val); + break; + case OPERATOR_DIV: + if (mpz_sgn(right_val) != 0) + mpz_tdiv_q(val, left_val, right_val); + else + { + error_at(location, "division by zero"); + mpz_set_ui(val, 0); + return true; + } + break; + case OPERATOR_MOD: + if (mpz_sgn(right_val) != 0) + mpz_tdiv_r(val, left_val, right_val); + else + { + error_at(location, "division by zero"); + mpz_set_ui(val, 0); + return true; + } + break; + case OPERATOR_LSHIFT: + { + unsigned long shift = mpz_get_ui(right_val); + if (mpz_cmp_ui(right_val, shift) != 0 || shift > 0x100000) + { + error_at(location, "shift count overflow"); + mpz_set_ui(val, 0); + return true; + } + mpz_mul_2exp(val, left_val, shift); + is_shift_op = true; + break; + } + break; + case OPERATOR_RSHIFT: + { + unsigned long shift = mpz_get_ui(right_val); + if (mpz_cmp_ui(right_val, shift) != 0) + { + error_at(location, "shift count overflow"); + mpz_set_ui(val, 0); + return true; + } + if (mpz_cmp_ui(left_val, 0) >= 0) + mpz_tdiv_q_2exp(val, left_val, shift); + else + mpz_fdiv_q_2exp(val, left_val, shift); + is_shift_op = true; + break; + } + break; + case OPERATOR_AND: + mpz_and(val, left_val, right_val); + break; + case OPERATOR_BITCLEAR: + { + mpz_t tval; + mpz_init(tval); + mpz_com(tval, right_val); + mpz_and(val, left_val, tval); + mpz_clear(tval); + } + break; + default: + gcc_unreachable(); + } + + Type* type = left_type; + if (!is_shift_op) + { + if (type == NULL) + type = right_type; + else if (type != right_type && right_type != NULL) + { + if (type->is_abstract()) + type = right_type; + else if (!right_type->is_abstract()) + { + // This look like a type error which should be diagnosed + // elsewhere. Don't do anything here, to avoid an + // unhelpful chain of error messages. + return true; + } + } + } + + if (type != NULL && !type->is_abstract()) + { + // We have to check the operands too, as we have implicitly + // coerced them to TYPE. + if ((type != left_type + && !Integer_expression::check_constant(left_val, type, location)) + || (!is_shift_op + && type != right_type + && !Integer_expression::check_constant(right_val, type, + location)) + || !Integer_expression::check_constant(val, type, location)) + mpz_set_ui(val, 0); + } + + return true; +} + +// Apply binary opcode OP to LEFT_VAL and RIGHT_VAL, setting VAL. +// Return true if this could be done, false if not. + +bool +Binary_expression::eval_float(Operator op, Type* left_type, mpfr_t left_val, + Type* right_type, mpfr_t right_val, + mpfr_t val, source_location location) +{ + switch (op) + { + case OPERATOR_OROR: + case OPERATOR_ANDAND: + case OPERATOR_EQEQ: + case OPERATOR_NOTEQ: + case OPERATOR_LT: + case OPERATOR_LE: + case OPERATOR_GT: + case OPERATOR_GE: + // These return boolean values. We should probably handle them + // anyhow in case a type conversion is used on the result. + return false; + case OPERATOR_PLUS: + mpfr_add(val, left_val, right_val, GMP_RNDN); + break; + case OPERATOR_MINUS: + mpfr_sub(val, left_val, right_val, GMP_RNDN); + break; + case OPERATOR_OR: + case OPERATOR_XOR: + case OPERATOR_AND: + case OPERATOR_BITCLEAR: + return false; + case OPERATOR_MULT: + mpfr_mul(val, left_val, right_val, GMP_RNDN); + break; + case OPERATOR_DIV: + if (mpfr_zero_p(right_val)) + error_at(location, "division by zero"); + mpfr_div(val, left_val, right_val, GMP_RNDN); + break; + case OPERATOR_MOD: + return false; + case OPERATOR_LSHIFT: + case OPERATOR_RSHIFT: + return false; + default: + gcc_unreachable(); + } + + Type* type = left_type; + if (type == NULL) + type = right_type; + else if (type != right_type && right_type != NULL) + { + if (type->is_abstract()) + type = right_type; + else if (!right_type->is_abstract()) + { + // This looks like a type error which should be diagnosed + // elsewhere. Don't do anything here, to avoid an unhelpful + // chain of error messages. + return true; + } + } + + if (type != NULL && !type->is_abstract()) + { + if ((type != left_type + && !Float_expression::check_constant(left_val, type, location)) + || (type != right_type + && !Float_expression::check_constant(right_val, type, + location)) + || !Float_expression::check_constant(val, type, location)) + mpfr_set_ui(val, 0, GMP_RNDN); + } + + return true; +} + +// Apply binary opcode OP to LEFT_REAL/LEFT_IMAG and +// RIGHT_REAL/RIGHT_IMAG, setting REAL/IMAG. Return true if this +// could be done, false if not. + +bool +Binary_expression::eval_complex(Operator op, Type* left_type, + mpfr_t left_real, mpfr_t left_imag, + Type *right_type, + mpfr_t right_real, mpfr_t right_imag, + mpfr_t real, mpfr_t imag, + source_location location) +{ + switch (op) + { + case OPERATOR_OROR: + case OPERATOR_ANDAND: + case OPERATOR_EQEQ: + case OPERATOR_NOTEQ: + case OPERATOR_LT: + case OPERATOR_LE: + case OPERATOR_GT: + case OPERATOR_GE: + // These return boolean values and must be handled differently. + return false; + case OPERATOR_PLUS: + mpfr_add(real, left_real, right_real, GMP_RNDN); + mpfr_add(imag, left_imag, right_imag, GMP_RNDN); + break; + case OPERATOR_MINUS: + mpfr_sub(real, left_real, right_real, GMP_RNDN); + mpfr_sub(imag, left_imag, right_imag, GMP_RNDN); + break; + case OPERATOR_OR: + case OPERATOR_XOR: + case OPERATOR_AND: + case OPERATOR_BITCLEAR: + return false; + case OPERATOR_MULT: + { + // You might think that multiplying two complex numbers would + // be simple, and you would be right, until you start to think + // about getting the right answer for infinity. If one + // operand here is infinity and the other is anything other + // than zero or NaN, then we are going to wind up subtracting + // two infinity values. That will give us a NaN, but the + // correct answer is infinity. + + mpfr_t lrrr; + mpfr_init(lrrr); + mpfr_mul(lrrr, left_real, right_real, GMP_RNDN); + + mpfr_t lrri; + mpfr_init(lrri); + mpfr_mul(lrri, left_real, right_imag, GMP_RNDN); + + mpfr_t lirr; + mpfr_init(lirr); + mpfr_mul(lirr, left_imag, right_real, GMP_RNDN); + + mpfr_t liri; + mpfr_init(liri); + mpfr_mul(liri, left_imag, right_imag, GMP_RNDN); + + mpfr_sub(real, lrrr, liri, GMP_RNDN); + mpfr_add(imag, lrri, lirr, GMP_RNDN); + + // If we get NaN on both sides, check whether it should really + // be infinity. The rule is that if either side of the + // complex number is infinity, then the whole value is + // infinity, even if the other side is NaN. So the only case + // we have to fix is the one in which both sides are NaN. + if (mpfr_nan_p(real) && mpfr_nan_p(imag) + && (!mpfr_nan_p(left_real) || !mpfr_nan_p(left_imag)) + && (!mpfr_nan_p(right_real) || !mpfr_nan_p(right_imag))) + { + bool is_infinity = false; + + mpfr_t lr; + mpfr_t li; + mpfr_init_set(lr, left_real, GMP_RNDN); + mpfr_init_set(li, left_imag, GMP_RNDN); + + mpfr_t rr; + mpfr_t ri; + mpfr_init_set(rr, right_real, GMP_RNDN); + mpfr_init_set(ri, right_imag, GMP_RNDN); + + // If the left side is infinity, then the result is + // infinity. + if (mpfr_inf_p(lr) || mpfr_inf_p(li)) + { + mpfr_set_ui(lr, mpfr_inf_p(lr) ? 1 : 0, GMP_RNDN); + mpfr_copysign(lr, lr, left_real, GMP_RNDN); + mpfr_set_ui(li, mpfr_inf_p(li) ? 1 : 0, GMP_RNDN); + mpfr_copysign(li, li, left_imag, GMP_RNDN); + if (mpfr_nan_p(rr)) + { + mpfr_set_ui(rr, 0, GMP_RNDN); + mpfr_copysign(rr, rr, right_real, GMP_RNDN); + } + if (mpfr_nan_p(ri)) + { + mpfr_set_ui(ri, 0, GMP_RNDN); + mpfr_copysign(ri, ri, right_imag, GMP_RNDN); + } + is_infinity = true; + } + + // If the right side is infinity, then the result is + // infinity. + if (mpfr_inf_p(rr) || mpfr_inf_p(ri)) + { + mpfr_set_ui(rr, mpfr_inf_p(rr) ? 1 : 0, GMP_RNDN); + mpfr_copysign(rr, rr, right_real, GMP_RNDN); + mpfr_set_ui(ri, mpfr_inf_p(ri) ? 1 : 0, GMP_RNDN); + mpfr_copysign(ri, ri, right_imag, GMP_RNDN); + if (mpfr_nan_p(lr)) + { + mpfr_set_ui(lr, 0, GMP_RNDN); + mpfr_copysign(lr, lr, left_real, GMP_RNDN); + } + if (mpfr_nan_p(li)) + { + mpfr_set_ui(li, 0, GMP_RNDN); + mpfr_copysign(li, li, left_imag, GMP_RNDN); + } + is_infinity = true; + } + + // If we got an overflow in the intermediate computations, + // then the result is infinity. + if (!is_infinity + && (mpfr_inf_p(lrrr) || mpfr_inf_p(lrri) + || mpfr_inf_p(lirr) || mpfr_inf_p(liri))) + { + if (mpfr_nan_p(lr)) + { + mpfr_set_ui(lr, 0, GMP_RNDN); + mpfr_copysign(lr, lr, left_real, GMP_RNDN); + } + if (mpfr_nan_p(li)) + { + mpfr_set_ui(li, 0, GMP_RNDN); + mpfr_copysign(li, li, left_imag, GMP_RNDN); + } + if (mpfr_nan_p(rr)) + { + mpfr_set_ui(rr, 0, GMP_RNDN); + mpfr_copysign(rr, rr, right_real, GMP_RNDN); + } + if (mpfr_nan_p(ri)) + { + mpfr_set_ui(ri, 0, GMP_RNDN); + mpfr_copysign(ri, ri, right_imag, GMP_RNDN); + } + is_infinity = true; + } + + if (is_infinity) + { + mpfr_mul(lrrr, lr, rr, GMP_RNDN); + mpfr_mul(lrri, lr, ri, GMP_RNDN); + mpfr_mul(lirr, li, rr, GMP_RNDN); + mpfr_mul(liri, li, ri, GMP_RNDN); + mpfr_sub(real, lrrr, liri, GMP_RNDN); + mpfr_add(imag, lrri, lirr, GMP_RNDN); + mpfr_set_inf(real, mpfr_sgn(real)); + mpfr_set_inf(imag, mpfr_sgn(imag)); + } + + mpfr_clear(lr); + mpfr_clear(li); + mpfr_clear(rr); + mpfr_clear(ri); + } + + mpfr_clear(lrrr); + mpfr_clear(lrri); + mpfr_clear(lirr); + mpfr_clear(liri); + } + break; + case OPERATOR_DIV: + { + // For complex division we want to avoid having an + // intermediate overflow turn the whole result in a NaN. We + // scale the values to try to avoid this. + + if (mpfr_zero_p(right_real) && mpfr_zero_p(right_imag)) + error_at(location, "division by zero"); + + mpfr_t rra; + mpfr_t ria; + mpfr_init(rra); + mpfr_init(ria); + mpfr_abs(rra, right_real, GMP_RNDN); + mpfr_abs(ria, right_imag, GMP_RNDN); + mpfr_t t; + mpfr_init(t); + mpfr_max(t, rra, ria, GMP_RNDN); + + mpfr_t rr; + mpfr_t ri; + mpfr_init_set(rr, right_real, GMP_RNDN); + mpfr_init_set(ri, right_imag, GMP_RNDN); + long ilogbw = 0; + if (!mpfr_inf_p(t) && !mpfr_nan_p(t) && !mpfr_zero_p(t)) + { + ilogbw = mpfr_get_exp(t); + mpfr_mul_2si(rr, rr, - ilogbw, GMP_RNDN); + mpfr_mul_2si(ri, ri, - ilogbw, GMP_RNDN); + } + + mpfr_t denom; + mpfr_init(denom); + mpfr_mul(denom, rr, rr, GMP_RNDN); + mpfr_mul(t, ri, ri, GMP_RNDN); + mpfr_add(denom, denom, t, GMP_RNDN); + + mpfr_mul(real, left_real, rr, GMP_RNDN); + mpfr_mul(t, left_imag, ri, GMP_RNDN); + mpfr_add(real, real, t, GMP_RNDN); + mpfr_div(real, real, denom, GMP_RNDN); + mpfr_mul_2si(real, real, - ilogbw, GMP_RNDN); + + mpfr_mul(imag, left_imag, rr, GMP_RNDN); + mpfr_mul(t, left_real, ri, GMP_RNDN); + mpfr_sub(imag, imag, t, GMP_RNDN); + mpfr_div(imag, imag, denom, GMP_RNDN); + mpfr_mul_2si(imag, imag, - ilogbw, GMP_RNDN); + + // If we wind up with NaN on both sides, check whether we + // should really have infinity. The rule is that if either + // side of the complex number is infinity, then the whole + // value is infinity, even if the other side is NaN. So the + // only case we have to fix is the one in which both sides are + // NaN. + if (mpfr_nan_p(real) && mpfr_nan_p(imag) + && (!mpfr_nan_p(left_real) || !mpfr_nan_p(left_imag)) + && (!mpfr_nan_p(right_real) || !mpfr_nan_p(right_imag))) + { + if (mpfr_zero_p(denom)) + { + mpfr_set_inf(real, mpfr_sgn(rr)); + mpfr_mul(real, real, left_real, GMP_RNDN); + mpfr_set_inf(imag, mpfr_sgn(rr)); + mpfr_mul(imag, imag, left_imag, GMP_RNDN); + } + else if ((mpfr_inf_p(left_real) || mpfr_inf_p(left_imag)) + && mpfr_number_p(rr) && mpfr_number_p(ri)) + { + mpfr_set_ui(t, mpfr_inf_p(left_real) ? 1 : 0, GMP_RNDN); + mpfr_copysign(t, t, left_real, GMP_RNDN); + + mpfr_t t2; + mpfr_init_set_ui(t2, mpfr_inf_p(left_imag) ? 1 : 0, GMP_RNDN); + mpfr_copysign(t2, t2, left_imag, GMP_RNDN); + + mpfr_t t3; + mpfr_init(t3); + mpfr_mul(t3, t, rr, GMP_RNDN); + + mpfr_t t4; + mpfr_init(t4); + mpfr_mul(t4, t2, ri, GMP_RNDN); + + mpfr_add(t3, t3, t4, GMP_RNDN); + mpfr_set_inf(real, mpfr_sgn(t3)); + + mpfr_mul(t3, t2, rr, GMP_RNDN); + mpfr_mul(t4, t, ri, GMP_RNDN); + mpfr_sub(t3, t3, t4, GMP_RNDN); + mpfr_set_inf(imag, mpfr_sgn(t3)); + + mpfr_clear(t2); + mpfr_clear(t3); + mpfr_clear(t4); + } + else if ((mpfr_inf_p(right_real) || mpfr_inf_p(right_imag)) + && mpfr_number_p(left_real) && mpfr_number_p(left_imag)) + { + mpfr_set_ui(t, mpfr_inf_p(rr) ? 1 : 0, GMP_RNDN); + mpfr_copysign(t, t, rr, GMP_RNDN); + + mpfr_t t2; + mpfr_init_set_ui(t2, mpfr_inf_p(ri) ? 1 : 0, GMP_RNDN); + mpfr_copysign(t2, t2, ri, GMP_RNDN); + + mpfr_t t3; + mpfr_init(t3); + mpfr_mul(t3, left_real, t, GMP_RNDN); + + mpfr_t t4; + mpfr_init(t4); + mpfr_mul(t4, left_imag, t2, GMP_RNDN); + + mpfr_add(t3, t3, t4, GMP_RNDN); + mpfr_set_ui(real, 0, GMP_RNDN); + mpfr_mul(real, real, t3, GMP_RNDN); + + mpfr_mul(t3, left_imag, t, GMP_RNDN); + mpfr_mul(t4, left_real, t2, GMP_RNDN); + mpfr_sub(t3, t3, t4, GMP_RNDN); + mpfr_set_ui(imag, 0, GMP_RNDN); + mpfr_mul(imag, imag, t3, GMP_RNDN); + + mpfr_clear(t2); + mpfr_clear(t3); + mpfr_clear(t4); + } + } + + mpfr_clear(denom); + mpfr_clear(rr); + mpfr_clear(ri); + mpfr_clear(t); + mpfr_clear(rra); + mpfr_clear(ria); + } + break; + case OPERATOR_MOD: + return false; + case OPERATOR_LSHIFT: + case OPERATOR_RSHIFT: + return false; + default: + gcc_unreachable(); + } + + Type* type = left_type; + if (type == NULL) + type = right_type; + else if (type != right_type && right_type != NULL) + { + if (type->is_abstract()) + type = right_type; + else if (!right_type->is_abstract()) + { + // This looks like a type error which should be diagnosed + // elsewhere. Don't do anything here, to avoid an unhelpful + // chain of error messages. + return true; + } + } + + if (type != NULL && !type->is_abstract()) + { + if ((type != left_type + && !Complex_expression::check_constant(left_real, left_imag, + type, location)) + || (type != right_type + && !Complex_expression::check_constant(right_real, right_imag, + type, location)) + || !Complex_expression::check_constant(real, imag, type, + location)) + { + mpfr_set_ui(real, 0, GMP_RNDN); + mpfr_set_ui(imag, 0, GMP_RNDN); + } + } + + return true; +} + +// Lower a binary expression. We have to evaluate constant +// expressions now, in order to implement Go's unlimited precision +// constants. + +Expression* +Binary_expression::do_lower(Gogo*, Named_object*, int) +{ + source_location location = this->location(); + Operator op = this->op_; + Expression* left = this->left_; + Expression* right = this->right_; + + const bool is_comparison = (op == OPERATOR_EQEQ + || op == OPERATOR_NOTEQ + || op == OPERATOR_LT + || op == OPERATOR_LE + || op == OPERATOR_GT + || op == OPERATOR_GE); + + // Integer constant expressions. + { + mpz_t left_val; + mpz_init(left_val); + Type* left_type; + mpz_t right_val; + mpz_init(right_val); + Type* right_type; + if (left->integer_constant_value(false, left_val, &left_type) + && right->integer_constant_value(false, right_val, &right_type)) + { + Expression* ret = NULL; + if (left_type != right_type + && left_type != NULL + && right_type != NULL + && left_type->base() != right_type->base() + && op != OPERATOR_LSHIFT + && op != OPERATOR_RSHIFT) + { + // May be a type error--let it be diagnosed later. + } + else if (is_comparison) + { + bool b = Binary_expression::compare_integer(op, left_val, + right_val); + ret = Expression::make_cast(Type::lookup_bool_type(), + Expression::make_boolean(b, location), + location); + } + else + { + mpz_t val; + mpz_init(val); + + if (Binary_expression::eval_integer(op, left_type, left_val, + right_type, right_val, + location, val)) + { + gcc_assert(op != OPERATOR_OROR && op != OPERATOR_ANDAND); + Type* type; + if (op == OPERATOR_LSHIFT || op == OPERATOR_RSHIFT) + type = left_type; + else if (left_type == NULL) + type = right_type; + else if (right_type == NULL) + type = left_type; + else if (!left_type->is_abstract() + && left_type->named_type() != NULL) + type = left_type; + else if (!right_type->is_abstract() + && right_type->named_type() != NULL) + type = right_type; + else if (!left_type->is_abstract()) + type = left_type; + else if (!right_type->is_abstract()) + type = right_type; + else if (left_type->float_type() != NULL) + type = left_type; + else if (right_type->float_type() != NULL) + type = right_type; + else if (left_type->complex_type() != NULL) + type = left_type; + else if (right_type->complex_type() != NULL) + type = right_type; + else + type = left_type; + ret = Expression::make_integer(&val, type, location); + } + + mpz_clear(val); + } + + if (ret != NULL) + { + mpz_clear(right_val); + mpz_clear(left_val); + return ret; + } + } + mpz_clear(right_val); + mpz_clear(left_val); + } + + // Floating point constant expressions. + { + mpfr_t left_val; + mpfr_init(left_val); + Type* left_type; + mpfr_t right_val; + mpfr_init(right_val); + Type* right_type; + if (left->float_constant_value(left_val, &left_type) + && right->float_constant_value(right_val, &right_type)) + { + Expression* ret = NULL; + if (left_type != right_type + && left_type != NULL + && right_type != NULL + && left_type->base() != right_type->base() + && op != OPERATOR_LSHIFT + && op != OPERATOR_RSHIFT) + { + // May be a type error--let it be diagnosed later. + } + else if (is_comparison) + { + bool b = Binary_expression::compare_float(op, + (left_type != NULL + ? left_type + : right_type), + left_val, right_val); + ret = Expression::make_boolean(b, location); + } + else + { + mpfr_t val; + mpfr_init(val); + + if (Binary_expression::eval_float(op, left_type, left_val, + right_type, right_val, val, + location)) + { + gcc_assert(op != OPERATOR_OROR && op != OPERATOR_ANDAND + && op != OPERATOR_LSHIFT && op != OPERATOR_RSHIFT); + Type* type; + if (left_type == NULL) + type = right_type; + else if (right_type == NULL) + type = left_type; + else if (!left_type->is_abstract() + && left_type->named_type() != NULL) + type = left_type; + else if (!right_type->is_abstract() + && right_type->named_type() != NULL) + type = right_type; + else if (!left_type->is_abstract()) + type = left_type; + else if (!right_type->is_abstract()) + type = right_type; + else if (left_type->float_type() != NULL) + type = left_type; + else if (right_type->float_type() != NULL) + type = right_type; + else + type = left_type; + ret = Expression::make_float(&val, type, location); + } + + mpfr_clear(val); + } + + if (ret != NULL) + { + mpfr_clear(right_val); + mpfr_clear(left_val); + return ret; + } + } + mpfr_clear(right_val); + mpfr_clear(left_val); + } + + // Complex constant expressions. + { + mpfr_t left_real; + mpfr_t left_imag; + mpfr_init(left_real); + mpfr_init(left_imag); + Type* left_type; + + mpfr_t right_real; + mpfr_t right_imag; + mpfr_init(right_real); + mpfr_init(right_imag); + Type* right_type; + + if (left->complex_constant_value(left_real, left_imag, &left_type) + && right->complex_constant_value(right_real, right_imag, &right_type)) + { + Expression* ret = NULL; + if (left_type != right_type + && left_type != NULL + && right_type != NULL + && left_type->base() != right_type->base()) + { + // May be a type error--let it be diagnosed later. + } + else if (op == OPERATOR_EQEQ || op == OPERATOR_NOTEQ) + { + bool b = Binary_expression::compare_complex(op, + (left_type != NULL + ? left_type + : right_type), + left_real, + left_imag, + right_real, + right_imag); + ret = Expression::make_boolean(b, location); + } + else + { + mpfr_t real; + mpfr_t imag; + mpfr_init(real); + mpfr_init(imag); + + if (Binary_expression::eval_complex(op, left_type, + left_real, left_imag, + right_type, + right_real, right_imag, + real, imag, + location)) + { + gcc_assert(op != OPERATOR_OROR && op != OPERATOR_ANDAND + && op != OPERATOR_LSHIFT && op != OPERATOR_RSHIFT); + Type* type; + if (left_type == NULL) + type = right_type; + else if (right_type == NULL) + type = left_type; + else if (!left_type->is_abstract() + && left_type->named_type() != NULL) + type = left_type; + else if (!right_type->is_abstract() + && right_type->named_type() != NULL) + type = right_type; + else if (!left_type->is_abstract()) + type = left_type; + else if (!right_type->is_abstract()) + type = right_type; + else if (left_type->complex_type() != NULL) + type = left_type; + else if (right_type->complex_type() != NULL) + type = right_type; + else + type = left_type; + ret = Expression::make_complex(&real, &imag, type, + location); + } + mpfr_clear(real); + mpfr_clear(imag); + } + + if (ret != NULL) + { + mpfr_clear(left_real); + mpfr_clear(left_imag); + mpfr_clear(right_real); + mpfr_clear(right_imag); + return ret; + } + } + + mpfr_clear(left_real); + mpfr_clear(left_imag); + mpfr_clear(right_real); + mpfr_clear(right_imag); + } + + // String constant expressions. + if (op == OPERATOR_PLUS + && left->type()->is_string_type() + && right->type()->is_string_type()) + { + std::string left_string; + std::string right_string; + if (left->string_constant_value(&left_string) + && right->string_constant_value(&right_string)) + return Expression::make_string(left_string + right_string, location); + } + + return this; +} + +// Return the integer constant value, if it has one. + +bool +Binary_expression::do_integer_constant_value(bool iota_is_constant, mpz_t val, + Type** ptype) const +{ + mpz_t left_val; + mpz_init(left_val); + Type* left_type; + if (!this->left_->integer_constant_value(iota_is_constant, left_val, + &left_type)) + { + mpz_clear(left_val); + return false; + } + + mpz_t right_val; + mpz_init(right_val); + Type* right_type; + if (!this->right_->integer_constant_value(iota_is_constant, right_val, + &right_type)) + { + mpz_clear(right_val); + mpz_clear(left_val); + return false; + } + + bool ret; + if (left_type != right_type + && left_type != NULL + && right_type != NULL + && left_type->base() != right_type->base() + && this->op_ != OPERATOR_RSHIFT + && this->op_ != OPERATOR_LSHIFT) + ret = false; + else + ret = Binary_expression::eval_integer(this->op_, left_type, left_val, + right_type, right_val, + this->location(), val); + + mpz_clear(right_val); + mpz_clear(left_val); + + if (ret) + *ptype = left_type; + + return ret; +} + +// Return the floating point constant value, if it has one. + +bool +Binary_expression::do_float_constant_value(mpfr_t val, Type** ptype) const +{ + mpfr_t left_val; + mpfr_init(left_val); + Type* left_type; + if (!this->left_->float_constant_value(left_val, &left_type)) + { + mpfr_clear(left_val); + return false; + } + + mpfr_t right_val; + mpfr_init(right_val); + Type* right_type; + if (!this->right_->float_constant_value(right_val, &right_type)) + { + mpfr_clear(right_val); + mpfr_clear(left_val); + return false; + } + + bool ret; + if (left_type != right_type + && left_type != NULL + && right_type != NULL + && left_type->base() != right_type->base()) + ret = false; + else + ret = Binary_expression::eval_float(this->op_, left_type, left_val, + right_type, right_val, + val, this->location()); + + mpfr_clear(left_val); + mpfr_clear(right_val); + + if (ret) + *ptype = left_type; + + return ret; +} + +// Return the complex constant value, if it has one. + +bool +Binary_expression::do_complex_constant_value(mpfr_t real, mpfr_t imag, + Type** ptype) const +{ + mpfr_t left_real; + mpfr_t left_imag; + mpfr_init(left_real); + mpfr_init(left_imag); + Type* left_type; + if (!this->left_->complex_constant_value(left_real, left_imag, &left_type)) + { + mpfr_clear(left_real); + mpfr_clear(left_imag); + return false; + } + + mpfr_t right_real; + mpfr_t right_imag; + mpfr_init(right_real); + mpfr_init(right_imag); + Type* right_type; + if (!this->right_->complex_constant_value(right_real, right_imag, + &right_type)) + { + mpfr_clear(left_real); + mpfr_clear(left_imag); + mpfr_clear(right_real); + mpfr_clear(right_imag); + return false; + } + + bool ret; + if (left_type != right_type + && left_type != NULL + && right_type != NULL + && left_type->base() != right_type->base()) + ret = false; + else + ret = Binary_expression::eval_complex(this->op_, left_type, + left_real, left_imag, + right_type, + right_real, right_imag, + real, imag, + this->location()); + mpfr_clear(left_real); + mpfr_clear(left_imag); + mpfr_clear(right_real); + mpfr_clear(right_imag); + + if (ret) + *ptype = left_type; + + return ret; +} + +// Note that the value is being discarded. + +void +Binary_expression::do_discarding_value() +{ + if (this->op_ == OPERATOR_OROR || this->op_ == OPERATOR_ANDAND) + this->right_->discarding_value(); + else + this->warn_about_unused_value(); +} + +// Get type. + +Type* +Binary_expression::do_type() +{ + if (this->classification() == EXPRESSION_ERROR) + return Type::make_error_type(); + + switch (this->op_) + { + case OPERATOR_OROR: + case OPERATOR_ANDAND: + case OPERATOR_EQEQ: + case OPERATOR_NOTEQ: + case OPERATOR_LT: + case OPERATOR_LE: + case OPERATOR_GT: + case OPERATOR_GE: + return Type::lookup_bool_type(); + + case OPERATOR_PLUS: + case OPERATOR_MINUS: + case OPERATOR_OR: + case OPERATOR_XOR: + case OPERATOR_MULT: + case OPERATOR_DIV: + case OPERATOR_MOD: + case OPERATOR_AND: + case OPERATOR_BITCLEAR: + { + Type* left_type = this->left_->type(); + Type* right_type = this->right_->type(); + if (left_type->is_error_type()) + return left_type; + else if (right_type->is_error_type()) + return right_type; + else if (!Type::are_compatible_for_binop(left_type, right_type)) + { + this->report_error(_("incompatible types in binary expression")); + return Type::make_error_type(); + } + else if (!left_type->is_abstract() && left_type->named_type() != NULL) + return left_type; + else if (!right_type->is_abstract() && right_type->named_type() != NULL) + return right_type; + else if (!left_type->is_abstract()) + return left_type; + else if (!right_type->is_abstract()) + return right_type; + else if (left_type->complex_type() != NULL) + return left_type; + else if (right_type->complex_type() != NULL) + return right_type; + else if (left_type->float_type() != NULL) + return left_type; + else if (right_type->float_type() != NULL) + return right_type; + else + return left_type; + } + + case OPERATOR_LSHIFT: + case OPERATOR_RSHIFT: + return this->left_->type(); + + default: + gcc_unreachable(); + } +} + +// Set type for a binary expression. + +void +Binary_expression::do_determine_type(const Type_context* context) +{ + Type* tleft = this->left_->type(); + Type* tright = this->right_->type(); + + // Both sides should have the same type, except for the shift + // operations. For a comparison, we should ignore the incoming + // type. + + bool is_shift_op = (this->op_ == OPERATOR_LSHIFT + || this->op_ == OPERATOR_RSHIFT); + + bool is_comparison = (this->op_ == OPERATOR_EQEQ + || this->op_ == OPERATOR_NOTEQ + || this->op_ == OPERATOR_LT + || this->op_ == OPERATOR_LE + || this->op_ == OPERATOR_GT + || this->op_ == OPERATOR_GE); + + Type_context subcontext(*context); + + if (is_comparison) + { + // In a comparison, the context does not determine the types of + // the operands. + subcontext.type = NULL; + } + + // Set the context for the left hand operand. + if (is_shift_op) + { + // The right hand operand plays no role in determining the type + // of the left hand operand. A shift of an abstract integer in + // a string context gets special treatment, which may be a + // language bug. + if (subcontext.type != NULL + && subcontext.type->is_string_type() + && tleft->is_abstract()) + error_at(this->location(), "shift of non-integer operand"); + } + else if (!tleft->is_abstract()) + subcontext.type = tleft; + else if (!tright->is_abstract()) + subcontext.type = tright; + else if (subcontext.type == NULL) + { + if ((tleft->integer_type() != NULL && tright->integer_type() != NULL) + || (tleft->float_type() != NULL && tright->float_type() != NULL) + || (tleft->complex_type() != NULL && tright->complex_type() != NULL)) + { + // Both sides have an abstract integer, abstract float, or + // abstract complex type. Just let CONTEXT determine + // whether they may remain abstract or not. + } + else if (tleft->complex_type() != NULL) + subcontext.type = tleft; + else if (tright->complex_type() != NULL) + subcontext.type = tright; + else if (tleft->float_type() != NULL) + subcontext.type = tleft; + else if (tright->float_type() != NULL) + subcontext.type = tright; + else + subcontext.type = tleft; + + if (subcontext.type != NULL && !context->may_be_abstract) + subcontext.type = subcontext.type->make_non_abstract_type(); + } + + this->left_->determine_type(&subcontext); + + // The context for the right hand operand is the same as for the + // left hand operand, except for a shift operator. + if (is_shift_op) + { + subcontext.type = Type::lookup_integer_type("uint"); + subcontext.may_be_abstract = false; + } + + this->right_->determine_type(&subcontext); +} + +// Report an error if the binary operator OP does not support TYPE. +// Return whether the operation is OK. This should not be used for +// shift. + +bool +Binary_expression::check_operator_type(Operator op, Type* type, + source_location location) +{ + switch (op) + { + case OPERATOR_OROR: + case OPERATOR_ANDAND: + if (!type->is_boolean_type()) + { + error_at(location, "expected boolean type"); + return false; + } + break; + + case OPERATOR_EQEQ: + case OPERATOR_NOTEQ: + if (type->integer_type() == NULL + && type->float_type() == NULL + && type->complex_type() == NULL + && !type->is_string_type() + && type->points_to() == NULL + && !type->is_nil_type() + && !type->is_boolean_type() + && type->interface_type() == NULL + && (type->array_type() == NULL + || type->array_type()->length() != NULL) + && type->map_type() == NULL + && type->channel_type() == NULL + && type->function_type() == NULL) + { + error_at(location, + ("expected integer, floating, complex, string, pointer, " + "boolean, interface, slice, map, channel, " + "or function type")); + return false; + } + break; + + case OPERATOR_LT: + case OPERATOR_LE: + case OPERATOR_GT: + case OPERATOR_GE: + if (type->integer_type() == NULL + && type->float_type() == NULL + && !type->is_string_type()) + { + error_at(location, "expected integer, floating, or string type"); + return false; + } + break; + + case OPERATOR_PLUS: + case OPERATOR_PLUSEQ: + if (type->integer_type() == NULL + && type->float_type() == NULL + && type->complex_type() == NULL + && !type->is_string_type()) + { + error_at(location, + "expected integer, floating, complex, or string type"); + return false; + } + break; + + case OPERATOR_MINUS: + case OPERATOR_MINUSEQ: + case OPERATOR_MULT: + case OPERATOR_MULTEQ: + case OPERATOR_DIV: + case OPERATOR_DIVEQ: + if (type->integer_type() == NULL + && type->float_type() == NULL + && type->complex_type() == NULL) + { + error_at(location, "expected integer, floating, or complex type"); + return false; + } + break; + + case OPERATOR_MOD: + case OPERATOR_MODEQ: + case OPERATOR_OR: + case OPERATOR_OREQ: + case OPERATOR_AND: + case OPERATOR_ANDEQ: + case OPERATOR_XOR: + case OPERATOR_XOREQ: + case OPERATOR_BITCLEAR: + case OPERATOR_BITCLEAREQ: + if (type->integer_type() == NULL) + { + error_at(location, "expected integer type"); + return false; + } + break; + + default: + gcc_unreachable(); + } + + return true; +} + +// Check types. + +void +Binary_expression::do_check_types(Gogo*) +{ + if (this->classification() == EXPRESSION_ERROR) + return; + + Type* left_type = this->left_->type(); + Type* right_type = this->right_->type(); + if (left_type->is_error_type() || right_type->is_error_type()) + { + this->set_is_error(); + return; + } + + if (this->op_ == OPERATOR_EQEQ + || this->op_ == OPERATOR_NOTEQ + || this->op_ == OPERATOR_LT + || this->op_ == OPERATOR_LE + || this->op_ == OPERATOR_GT + || this->op_ == OPERATOR_GE) + { + if (!Type::are_assignable(left_type, right_type, NULL) + && !Type::are_assignable(right_type, left_type, NULL)) + { + this->report_error(_("incompatible types in binary expression")); + return; + } + if (!Binary_expression::check_operator_type(this->op_, left_type, + this->location()) + || !Binary_expression::check_operator_type(this->op_, right_type, + this->location())) + { + this->set_is_error(); + return; + } + } + else if (this->op_ != OPERATOR_LSHIFT && this->op_ != OPERATOR_RSHIFT) + { + if (!Type::are_compatible_for_binop(left_type, right_type)) + { + this->report_error(_("incompatible types in binary expression")); + return; + } + if (!Binary_expression::check_operator_type(this->op_, left_type, + this->location())) + { + this->set_is_error(); + return; + } + } + else + { + if (left_type->integer_type() == NULL) + this->report_error(_("shift of non-integer operand")); + + if (!right_type->is_abstract() + && (right_type->integer_type() == NULL + || !right_type->integer_type()->is_unsigned())) + this->report_error(_("shift count not unsigned integer")); + else + { + mpz_t val; + mpz_init(val); + Type* type; + if (this->right_->integer_constant_value(true, val, &type)) + { + if (mpz_sgn(val) < 0) + this->report_error(_("negative shift count")); + } + mpz_clear(val); + } + } +} + +// Get a tree for a binary expression. + +tree +Binary_expression::do_get_tree(Translate_context* context) +{ + tree left = this->left_->get_tree(context); + tree right = this->right_->get_tree(context); + + if (left == error_mark_node || right == error_mark_node) + return error_mark_node; + + enum tree_code code; + bool use_left_type = true; + bool is_shift_op = false; + switch (this->op_) + { + case OPERATOR_EQEQ: + case OPERATOR_NOTEQ: + case OPERATOR_LT: + case OPERATOR_LE: + case OPERATOR_GT: + case OPERATOR_GE: + return Expression::comparison_tree(context, this->op_, + this->left_->type(), left, + this->right_->type(), right, + this->location()); + + case OPERATOR_OROR: + code = TRUTH_ORIF_EXPR; + use_left_type = false; + break; + case OPERATOR_ANDAND: + code = TRUTH_ANDIF_EXPR; + use_left_type = false; + break; + case OPERATOR_PLUS: + code = PLUS_EXPR; + break; + case OPERATOR_MINUS: + code = MINUS_EXPR; + break; + case OPERATOR_OR: + code = BIT_IOR_EXPR; + break; + case OPERATOR_XOR: + code = BIT_XOR_EXPR; + break; + case OPERATOR_MULT: + code = MULT_EXPR; + break; + case OPERATOR_DIV: + { + Type *t = this->left_->type(); + if (t->float_type() != NULL || t->complex_type() != NULL) + code = RDIV_EXPR; + else + code = TRUNC_DIV_EXPR; + } + break; + case OPERATOR_MOD: + code = TRUNC_MOD_EXPR; + break; + case OPERATOR_LSHIFT: + code = LSHIFT_EXPR; + is_shift_op = true; + break; + case OPERATOR_RSHIFT: + code = RSHIFT_EXPR; + is_shift_op = true; + break; + case OPERATOR_AND: + code = BIT_AND_EXPR; + break; + case OPERATOR_BITCLEAR: + right = fold_build1(BIT_NOT_EXPR, TREE_TYPE(right), right); + code = BIT_AND_EXPR; + break; + default: + gcc_unreachable(); + } + + tree type = use_left_type ? TREE_TYPE(left) : TREE_TYPE(right); + + if (this->left_->type()->is_string_type()) + { + gcc_assert(this->op_ == OPERATOR_PLUS); + tree string_type = Type::make_string_type()->get_tree(context->gogo()); + static tree string_plus_decl; + return Gogo::call_builtin(&string_plus_decl, + this->location(), + "__go_string_plus", + 2, + string_type, + string_type, + left, + string_type, + right); + } + + tree compute_type = excess_precision_type(type); + if (compute_type != NULL_TREE) + { + left = ::convert(compute_type, left); + right = ::convert(compute_type, right); + } + + tree eval_saved = NULL_TREE; + if (is_shift_op) + { + // Make sure the values are evaluated. + if (!DECL_P(left) && TREE_SIDE_EFFECTS(left)) + { + left = save_expr(left); + eval_saved = left; + } + if (!DECL_P(right) && TREE_SIDE_EFFECTS(right)) + { + right = save_expr(right); + if (eval_saved == NULL_TREE) + eval_saved = right; + else + eval_saved = fold_build2_loc(this->location(), COMPOUND_EXPR, + void_type_node, eval_saved, right); + } + } + + tree ret = fold_build2_loc(this->location(), + code, + compute_type != NULL_TREE ? compute_type : type, + left, right); + + if (compute_type != NULL_TREE) + ret = ::convert(type, ret); + + // In Go, a shift larger than the size of the type is well-defined. + // This is not true in GENERIC, so we need to insert a conditional. + if (is_shift_op) + { + gcc_assert(INTEGRAL_TYPE_P(TREE_TYPE(left))); + gcc_assert(this->left_->type()->integer_type() != NULL); + int bits = TYPE_PRECISION(TREE_TYPE(left)); + + tree compare = fold_build2(LT_EXPR, boolean_type_node, right, + build_int_cst_type(TREE_TYPE(right), bits)); + + tree overflow_result = fold_convert_loc(this->location(), + TREE_TYPE(left), + integer_zero_node); + if (this->op_ == OPERATOR_RSHIFT + && !this->left_->type()->integer_type()->is_unsigned()) + { + tree neg = fold_build2_loc(this->location(), LT_EXPR, + boolean_type_node, left, + fold_convert_loc(this->location(), + TREE_TYPE(left), + integer_zero_node)); + tree neg_one = fold_build2_loc(this->location(), + MINUS_EXPR, TREE_TYPE(left), + fold_convert_loc(this->location(), + TREE_TYPE(left), + integer_zero_node), + fold_convert_loc(this->location(), + TREE_TYPE(left), + integer_one_node)); + overflow_result = fold_build3_loc(this->location(), COND_EXPR, + TREE_TYPE(left), neg, neg_one, + overflow_result); + } + + ret = fold_build3_loc(this->location(), COND_EXPR, TREE_TYPE(left), + compare, ret, overflow_result); + + if (eval_saved != NULL_TREE) + ret = fold_build2_loc(this->location(), COMPOUND_EXPR, + TREE_TYPE(ret), eval_saved, ret); + } + + return ret; +} + +// Export a binary expression. + +void +Binary_expression::do_export(Export* exp) const +{ + exp->write_c_string("("); + this->left_->export_expression(exp); + switch (this->op_) + { + case OPERATOR_OROR: + exp->write_c_string(" || "); + break; + case OPERATOR_ANDAND: + exp->write_c_string(" && "); + break; + case OPERATOR_EQEQ: + exp->write_c_string(" == "); + break; + case OPERATOR_NOTEQ: + exp->write_c_string(" != "); + break; + case OPERATOR_LT: + exp->write_c_string(" < "); + break; + case OPERATOR_LE: + exp->write_c_string(" <= "); + break; + case OPERATOR_GT: + exp->write_c_string(" > "); + break; + case OPERATOR_GE: + exp->write_c_string(" >= "); + break; + case OPERATOR_PLUS: + exp->write_c_string(" + "); + break; + case OPERATOR_MINUS: + exp->write_c_string(" - "); + break; + case OPERATOR_OR: + exp->write_c_string(" | "); + break; + case OPERATOR_XOR: + exp->write_c_string(" ^ "); + break; + case OPERATOR_MULT: + exp->write_c_string(" * "); + break; + case OPERATOR_DIV: + exp->write_c_string(" / "); + break; + case OPERATOR_MOD: + exp->write_c_string(" % "); + break; + case OPERATOR_LSHIFT: + exp->write_c_string(" << "); + break; + case OPERATOR_RSHIFT: + exp->write_c_string(" >> "); + break; + case OPERATOR_AND: + exp->write_c_string(" & "); + break; + case OPERATOR_BITCLEAR: + exp->write_c_string(" &^ "); + break; + default: + gcc_unreachable(); + } + this->right_->export_expression(exp); + exp->write_c_string(")"); +} + +// Import a binary expression. + +Expression* +Binary_expression::do_import(Import* imp) +{ + imp->require_c_string("("); + + Expression* left = Expression::import_expression(imp); + + Operator op; + if (imp->match_c_string(" || ")) + { + op = OPERATOR_OROR; + imp->advance(4); + } + else if (imp->match_c_string(" && ")) + { + op = OPERATOR_ANDAND; + imp->advance(4); + } + else if (imp->match_c_string(" == ")) + { + op = OPERATOR_EQEQ; + imp->advance(4); + } + else if (imp->match_c_string(" != ")) + { + op = OPERATOR_NOTEQ; + imp->advance(4); + } + else if (imp->match_c_string(" < ")) + { + op = OPERATOR_LT; + imp->advance(3); + } + else if (imp->match_c_string(" <= ")) + { + op = OPERATOR_LE; + imp->advance(4); + } + else if (imp->match_c_string(" > ")) + { + op = OPERATOR_GT; + imp->advance(3); + } + else if (imp->match_c_string(" >= ")) + { + op = OPERATOR_GE; + imp->advance(4); + } + else if (imp->match_c_string(" + ")) + { + op = OPERATOR_PLUS; + imp->advance(3); + } + else if (imp->match_c_string(" - ")) + { + op = OPERATOR_MINUS; + imp->advance(3); + } + else if (imp->match_c_string(" | ")) + { + op = OPERATOR_OR; + imp->advance(3); + } + else if (imp->match_c_string(" ^ ")) + { + op = OPERATOR_XOR; + imp->advance(3); + } + else if (imp->match_c_string(" * ")) + { + op = OPERATOR_MULT; + imp->advance(3); + } + else if (imp->match_c_string(" / ")) + { + op = OPERATOR_DIV; + imp->advance(3); + } + else if (imp->match_c_string(" % ")) + { + op = OPERATOR_MOD; + imp->advance(3); + } + else if (imp->match_c_string(" << ")) + { + op = OPERATOR_LSHIFT; + imp->advance(4); + } + else if (imp->match_c_string(" >> ")) + { + op = OPERATOR_RSHIFT; + imp->advance(4); + } + else if (imp->match_c_string(" & ")) + { + op = OPERATOR_AND; + imp->advance(3); + } + else if (imp->match_c_string(" &^ ")) + { + op = OPERATOR_BITCLEAR; + imp->advance(4); + } + else + { + error_at(imp->location(), "unrecognized binary operator"); + return Expression::make_error(imp->location()); + } + + Expression* right = Expression::import_expression(imp); + + imp->require_c_string(")"); + + return Expression::make_binary(op, left, right, imp->location()); +} + +// Make a binary expression. + +Expression* +Expression::make_binary(Operator op, Expression* left, Expression* right, + source_location location) +{ + return new Binary_expression(op, left, right, location); +} + +// Implement a comparison. + +tree +Expression::comparison_tree(Translate_context* context, Operator op, + Type* left_type, tree left_tree, + Type* right_type, tree right_tree, + source_location location) +{ + enum tree_code code; + switch (op) + { + case OPERATOR_EQEQ: + code = EQ_EXPR; + break; + case OPERATOR_NOTEQ: + code = NE_EXPR; + break; + case OPERATOR_LT: + code = LT_EXPR; + break; + case OPERATOR_LE: + code = LE_EXPR; + break; + case OPERATOR_GT: + code = GT_EXPR; + break; + case OPERATOR_GE: + code = GE_EXPR; + break; + default: + gcc_unreachable(); + } + + if (left_type->is_string_type() && right_type->is_string_type()) + { + tree string_type = Type::make_string_type()->get_tree(context->gogo()); + static tree string_compare_decl; + left_tree = Gogo::call_builtin(&string_compare_decl, + location, + "__go_strcmp", + 2, + integer_type_node, + string_type, + left_tree, + string_type, + right_tree); + right_tree = build_int_cst_type(integer_type_node, 0); + } + else if ((left_type->interface_type() != NULL + && right_type->interface_type() == NULL + && !right_type->is_nil_type()) + || (left_type->interface_type() == NULL + && !left_type->is_nil_type() + && right_type->interface_type() != NULL)) + { + // Comparing an interface value to a non-interface value. + if (left_type->interface_type() == NULL) + { + std::swap(left_type, right_type); + std::swap(left_tree, right_tree); + } + + // The right operand is not an interface. We need to take its + // address if it is not a pointer. + tree make_tmp; + tree arg; + if (right_type->points_to() != NULL) + { + make_tmp = NULL_TREE; + arg = right_tree; + } + else if (TREE_ADDRESSABLE(TREE_TYPE(right_tree)) || DECL_P(right_tree)) + { + make_tmp = NULL_TREE; + arg = build_fold_addr_expr_loc(location, right_tree); + if (DECL_P(right_tree)) + TREE_ADDRESSABLE(right_tree) = 1; + } + else + { + tree tmp = create_tmp_var(TREE_TYPE(right_tree), + get_name(right_tree)); + DECL_IGNORED_P(tmp) = 0; + DECL_INITIAL(tmp) = right_tree; + TREE_ADDRESSABLE(tmp) = 1; + make_tmp = build1(DECL_EXPR, void_type_node, tmp); + SET_EXPR_LOCATION(make_tmp, location); + arg = build_fold_addr_expr_loc(location, tmp); + } + arg = fold_convert_loc(location, ptr_type_node, arg); + + tree descriptor = right_type->type_descriptor_pointer(context->gogo()); + + if (left_type->interface_type()->is_empty()) + { + static tree empty_interface_value_compare_decl; + left_tree = Gogo::call_builtin(&empty_interface_value_compare_decl, + location, + "__go_empty_interface_value_compare", + 3, + integer_type_node, + TREE_TYPE(left_tree), + left_tree, + TREE_TYPE(descriptor), + descriptor, + ptr_type_node, + arg); + if (left_tree == error_mark_node) + return error_mark_node; + // This can panic if the type is not comparable. + TREE_NOTHROW(empty_interface_value_compare_decl) = 0; + } + else + { + static tree interface_value_compare_decl; + left_tree = Gogo::call_builtin(&interface_value_compare_decl, + location, + "__go_interface_value_compare", + 3, + integer_type_node, + TREE_TYPE(left_tree), + left_tree, + TREE_TYPE(descriptor), + descriptor, + ptr_type_node, + arg); + if (left_tree == error_mark_node) + return error_mark_node; + // This can panic if the type is not comparable. + TREE_NOTHROW(interface_value_compare_decl) = 0; + } + right_tree = build_int_cst_type(integer_type_node, 0); + + if (make_tmp != NULL_TREE) + left_tree = build2(COMPOUND_EXPR, TREE_TYPE(left_tree), make_tmp, + left_tree); + } + else if (left_type->interface_type() != NULL + && right_type->interface_type() != NULL) + { + if (left_type->interface_type()->is_empty() + && right_type->interface_type()->is_empty()) + { + static tree empty_interface_compare_decl; + left_tree = Gogo::call_builtin(&empty_interface_compare_decl, + location, + "__go_empty_interface_compare", + 2, + integer_type_node, + TREE_TYPE(left_tree), + left_tree, + TREE_TYPE(right_tree), + right_tree); + if (left_tree == error_mark_node) + return error_mark_node; + // This can panic if the type is uncomparable. + TREE_NOTHROW(empty_interface_compare_decl) = 0; + } + else if (!left_type->interface_type()->is_empty() + && !right_type->interface_type()->is_empty()) + { + static tree interface_compare_decl; + left_tree = Gogo::call_builtin(&interface_compare_decl, + location, + "__go_interface_compare", + 2, + integer_type_node, + TREE_TYPE(left_tree), + left_tree, + TREE_TYPE(right_tree), + right_tree); + if (left_tree == error_mark_node) + return error_mark_node; + // This can panic if the type is uncomparable. + TREE_NOTHROW(interface_compare_decl) = 0; + } + else + { + if (left_type->interface_type()->is_empty()) + { + gcc_assert(op == OPERATOR_EQEQ || op == OPERATOR_NOTEQ); + std::swap(left_type, right_type); + std::swap(left_tree, right_tree); + } + gcc_assert(!left_type->interface_type()->is_empty()); + gcc_assert(right_type->interface_type()->is_empty()); + static tree interface_empty_compare_decl; + left_tree = Gogo::call_builtin(&interface_empty_compare_decl, + location, + "__go_interface_empty_compare", + 2, + integer_type_node, + TREE_TYPE(left_tree), + left_tree, + TREE_TYPE(right_tree), + right_tree); + if (left_tree == error_mark_node) + return error_mark_node; + // This can panic if the type is uncomparable. + TREE_NOTHROW(interface_empty_compare_decl) = 0; + } + + right_tree = build_int_cst_type(integer_type_node, 0); + } + + if (left_type->is_nil_type() + && (op == OPERATOR_EQEQ || op == OPERATOR_NOTEQ)) + { + std::swap(left_type, right_type); + std::swap(left_tree, right_tree); + } + + if (right_type->is_nil_type()) + { + if (left_type->array_type() != NULL + && left_type->array_type()->length() == NULL) + { + Array_type* at = left_type->array_type(); + left_tree = at->value_pointer_tree(context->gogo(), left_tree); + right_tree = fold_convert(TREE_TYPE(left_tree), null_pointer_node); + } + else if (left_type->interface_type() != NULL) + { + // An interface is nil if the first field is nil. + tree left_type_tree = TREE_TYPE(left_tree); + gcc_assert(TREE_CODE(left_type_tree) == RECORD_TYPE); + tree field = TYPE_FIELDS(left_type_tree); + left_tree = build3(COMPONENT_REF, TREE_TYPE(field), left_tree, + field, NULL_TREE); + right_tree = fold_convert(TREE_TYPE(left_tree), null_pointer_node); + } + else + { + gcc_assert(POINTER_TYPE_P(TREE_TYPE(left_tree))); + right_tree = fold_convert(TREE_TYPE(left_tree), null_pointer_node); + } + } + + if (left_tree == error_mark_node || right_tree == error_mark_node) + return error_mark_node; + + tree ret = fold_build2(code, boolean_type_node, left_tree, right_tree); + if (CAN_HAVE_LOCATION_P(ret)) + SET_EXPR_LOCATION(ret, location); + return ret; +} + +// Class Bound_method_expression. + +// Traversal. + +int +Bound_method_expression::do_traverse(Traverse* traverse) +{ + if (Expression::traverse(&this->expr_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return Expression::traverse(&this->method_, traverse); +} + +// Return the type of a bound method expression. The type of this +// object is really the type of the method with no receiver. We +// should be able to get away with just returning the type of the +// method. + +Type* +Bound_method_expression::do_type() +{ + return this->method_->type(); +} + +// Determine the types of a method expression. + +void +Bound_method_expression::do_determine_type(const Type_context*) +{ + this->method_->determine_type_no_context(); + Type* mtype = this->method_->type(); + Function_type* fntype = mtype == NULL ? NULL : mtype->function_type(); + if (fntype == NULL || !fntype->is_method()) + this->expr_->determine_type_no_context(); + else + { + Type_context subcontext(fntype->receiver()->type(), false); + this->expr_->determine_type(&subcontext); + } +} + +// Check the types of a method expression. + +void +Bound_method_expression::do_check_types(Gogo*) +{ + Type* type = this->method_->type()->deref(); + if (type == NULL + || type->function_type() == NULL + || !type->function_type()->is_method()) + this->report_error(_("object is not a method")); + else + { + Type* rtype = type->function_type()->receiver()->type()->deref(); + Type* etype = (this->expr_type_ != NULL + ? this->expr_type_ + : this->expr_->type()); + etype = etype->deref(); + if (!Type::are_identical(rtype, etype, true, NULL)) + this->report_error(_("method type does not match object type")); + } +} + +// Get the tree for a method expression. There is no standard tree +// representation for this. The only places it may currently be used +// are in a Call_expression or a Go_statement, which will take it +// apart directly. So this has nothing to do at present. + +tree +Bound_method_expression::do_get_tree(Translate_context*) +{ + error_at(this->location(), "reference to method other than calling it"); + return error_mark_node; +} + +// Make a method expression. + +Bound_method_expression* +Expression::make_bound_method(Expression* expr, Expression* method, + source_location location) +{ + return new Bound_method_expression(expr, method, location); +} + +// Class Builtin_call_expression. This is used for a call to a +// builtin function. + +class Builtin_call_expression : public Call_expression +{ + public: + Builtin_call_expression(Gogo* gogo, Expression* fn, Expression_list* args, + bool is_varargs, source_location location); + + protected: + // This overrides Call_expression::do_lower. + Expression* + do_lower(Gogo*, Named_object*, int); + + bool + do_is_constant() const; + + bool + do_integer_constant_value(bool, mpz_t, Type**) const; + + bool + do_float_constant_value(mpfr_t, Type**) const; + + bool + do_complex_constant_value(mpfr_t, mpfr_t, Type**) const; + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return new Builtin_call_expression(this->gogo_, this->fn()->copy(), + this->args()->copy(), + this->is_varargs(), + this->location()); + } + + tree + do_get_tree(Translate_context*); + + void + do_export(Export*) const; + + virtual bool + do_is_recover_call() const; + + virtual void + do_set_recover_arg(Expression*); + + private: + // The builtin functions. + enum Builtin_function_code + { + BUILTIN_INVALID, + + // Predeclared builtin functions. + BUILTIN_APPEND, + BUILTIN_CAP, + BUILTIN_CLOSE, + BUILTIN_CLOSED, + BUILTIN_COMPLEX, + BUILTIN_COPY, + BUILTIN_IMAG, + BUILTIN_LEN, + BUILTIN_MAKE, + BUILTIN_NEW, + BUILTIN_PANIC, + BUILTIN_PRINT, + BUILTIN_PRINTLN, + BUILTIN_REAL, + BUILTIN_RECOVER, + + // Builtin functions from the unsafe package. + BUILTIN_ALIGNOF, + BUILTIN_OFFSETOF, + BUILTIN_SIZEOF + }; + + Expression* + one_arg() const; + + bool + check_one_arg(); + + static Type* + real_imag_type(Type*); + + static Type* + complex_type(Type*); + + // A pointer back to the general IR structure. This avoids a global + // variable, or passing it around everywhere. + Gogo* gogo_; + // The builtin function being called. + Builtin_function_code code_; + // Used to stop endless loops when the length of an array uses len + // or cap of the array itself. + mutable bool seen_; +}; + +Builtin_call_expression::Builtin_call_expression(Gogo* gogo, + Expression* fn, + Expression_list* args, + bool is_varargs, + source_location location) + : Call_expression(fn, args, is_varargs, location), + gogo_(gogo), code_(BUILTIN_INVALID), seen_(false) +{ + Func_expression* fnexp = this->fn()->func_expression(); + gcc_assert(fnexp != NULL); + const std::string& name(fnexp->named_object()->name()); + if (name == "append") + this->code_ = BUILTIN_APPEND; + else if (name == "cap") + this->code_ = BUILTIN_CAP; + else if (name == "close") + this->code_ = BUILTIN_CLOSE; + else if (name == "closed") + this->code_ = BUILTIN_CLOSED; + else if (name == "complex") + this->code_ = BUILTIN_COMPLEX; + else if (name == "copy") + this->code_ = BUILTIN_COPY; + else if (name == "imag") + this->code_ = BUILTIN_IMAG; + else if (name == "len") + this->code_ = BUILTIN_LEN; + else if (name == "make") + this->code_ = BUILTIN_MAKE; + else if (name == "new") + this->code_ = BUILTIN_NEW; + else if (name == "panic") + this->code_ = BUILTIN_PANIC; + else if (name == "print") + this->code_ = BUILTIN_PRINT; + else if (name == "println") + this->code_ = BUILTIN_PRINTLN; + else if (name == "real") + this->code_ = BUILTIN_REAL; + else if (name == "recover") + this->code_ = BUILTIN_RECOVER; + else if (name == "Alignof") + this->code_ = BUILTIN_ALIGNOF; + else if (name == "Offsetof") + this->code_ = BUILTIN_OFFSETOF; + else if (name == "Sizeof") + this->code_ = BUILTIN_SIZEOF; + else + gcc_unreachable(); +} + +// Return whether this is a call to recover. This is a virtual +// function called from the parent class. + +bool +Builtin_call_expression::do_is_recover_call() const +{ + if (this->classification() == EXPRESSION_ERROR) + return false; + return this->code_ == BUILTIN_RECOVER; +} + +// Set the argument for a call to recover. + +void +Builtin_call_expression::do_set_recover_arg(Expression* arg) +{ + const Expression_list* args = this->args(); + gcc_assert(args == NULL || args->empty()); + Expression_list* new_args = new Expression_list(); + new_args->push_back(arg); + this->set_args(new_args); +} + +// A traversal class which looks for a call expression. + +class Find_call_expression : public Traverse +{ + public: + Find_call_expression() + : Traverse(traverse_expressions), + found_(false) + { } + + int + expression(Expression**); + + bool + found() + { return this->found_; } + + private: + bool found_; +}; + +int +Find_call_expression::expression(Expression** pexpr) +{ + if ((*pexpr)->call_expression() != NULL) + { + this->found_ = true; + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +// Lower a builtin call expression. This turns new and make into +// specific expressions. We also convert to a constant if we can. + +Expression* +Builtin_call_expression::do_lower(Gogo* gogo, Named_object* function, int) +{ + if (this->code_ == BUILTIN_NEW) + { + const Expression_list* args = this->args(); + if (args == NULL || args->size() < 1) + this->report_error(_("not enough arguments")); + else if (args->size() > 1) + this->report_error(_("too many arguments")); + else + { + Expression* arg = args->front(); + if (!arg->is_type_expression()) + { + error_at(arg->location(), "expected type"); + this->set_is_error(); + } + else + return Expression::make_allocation(arg->type(), this->location()); + } + } + else if (this->code_ == BUILTIN_MAKE) + { + const Expression_list* args = this->args(); + if (args == NULL || args->size() < 1) + this->report_error(_("not enough arguments")); + else + { + Expression* arg = args->front(); + if (!arg->is_type_expression()) + { + error_at(arg->location(), "expected type"); + this->set_is_error(); + } + else + { + Expression_list* newargs; + if (args->size() == 1) + newargs = NULL; + else + { + newargs = new Expression_list(); + Expression_list::const_iterator p = args->begin(); + ++p; + for (; p != args->end(); ++p) + newargs->push_back(*p); + } + return Expression::make_make(arg->type(), newargs, + this->location()); + } + } + } + else if (this->is_constant()) + { + // We can only lower len and cap if there are no function calls + // in the arguments. Otherwise we have to make the call. + if (this->code_ == BUILTIN_LEN || this->code_ == BUILTIN_CAP) + { + Expression* arg = this->one_arg(); + if (!arg->is_constant()) + { + Find_call_expression find_call; + Expression::traverse(&arg, &find_call); + if (find_call.found()) + return this; + } + } + + mpz_t ival; + mpz_init(ival); + Type* type; + if (this->integer_constant_value(true, ival, &type)) + { + Expression* ret = Expression::make_integer(&ival, type, + this->location()); + mpz_clear(ival); + return ret; + } + mpz_clear(ival); + + mpfr_t rval; + mpfr_init(rval); + if (this->float_constant_value(rval, &type)) + { + Expression* ret = Expression::make_float(&rval, type, + this->location()); + mpfr_clear(rval); + return ret; + } + + mpfr_t imag; + mpfr_init(imag); + if (this->complex_constant_value(rval, imag, &type)) + { + Expression* ret = Expression::make_complex(&rval, &imag, type, + this->location()); + mpfr_clear(rval); + mpfr_clear(imag); + return ret; + } + mpfr_clear(rval); + mpfr_clear(imag); + } + else if (this->code_ == BUILTIN_RECOVER) + { + if (function != NULL) + function->func_value()->set_calls_recover(); + else + { + // Calling recover outside of a function always returns the + // nil empty interface. + Type* eface = Type::make_interface_type(NULL, this->location()); + return Expression::make_cast(eface, + Expression::make_nil(this->location()), + this->location()); + } + } + else if (this->code_ == BUILTIN_APPEND) + { + // Lower the varargs. + const Expression_list* args = this->args(); + if (args == NULL || args->empty()) + return this; + Type* slice_type = args->front()->type(); + if (!slice_type->is_open_array_type()) + { + error_at(args->front()->location(), "argument 1 must be a slice"); + this->set_is_error(); + return this; + } + return this->lower_varargs(gogo, function, slice_type, 2); + } + + return this; +} + +// Return the type of the real or imag functions, given the type of +// the argument. We need to map complex to float, complex64 to +// float32, and complex128 to float64, so it has to be done by name. +// This returns NULL if it can't figure out the type. + +Type* +Builtin_call_expression::real_imag_type(Type* arg_type) +{ + if (arg_type == NULL || arg_type->is_abstract()) + return NULL; + Named_type* nt = arg_type->named_type(); + if (nt == NULL) + return NULL; + while (nt->real_type()->named_type() != NULL) + nt = nt->real_type()->named_type(); + if (nt->name() == "complex64") + return Type::lookup_float_type("float32"); + else if (nt->name() == "complex128") + return Type::lookup_float_type("float64"); + else + return NULL; +} + +// Return the type of the complex function, given the type of one of the +// argments. Like real_imag_type, we have to map by name. + +Type* +Builtin_call_expression::complex_type(Type* arg_type) +{ + if (arg_type == NULL || arg_type->is_abstract()) + return NULL; + Named_type* nt = arg_type->named_type(); + if (nt == NULL) + return NULL; + while (nt->real_type()->named_type() != NULL) + nt = nt->real_type()->named_type(); + if (nt->name() == "float32") + return Type::lookup_complex_type("complex64"); + else if (nt->name() == "float64") + return Type::lookup_complex_type("complex128"); + else + return NULL; +} + +// Return a single argument, or NULL if there isn't one. + +Expression* +Builtin_call_expression::one_arg() const +{ + const Expression_list* args = this->args(); + if (args->size() != 1) + return NULL; + return args->front(); +} + +// Return whether this is constant: len of a string, or len or cap of +// a fixed array, or unsafe.Sizeof, unsafe.Offsetof, unsafe.Alignof. + +bool +Builtin_call_expression::do_is_constant() const +{ + switch (this->code_) + { + case BUILTIN_LEN: + case BUILTIN_CAP: + { + if (this->seen_) + return false; + + Expression* arg = this->one_arg(); + if (arg == NULL) + return false; + Type* arg_type = arg->type(); + + if (arg_type->points_to() != NULL + && arg_type->points_to()->array_type() != NULL + && !arg_type->points_to()->is_open_array_type()) + arg_type = arg_type->points_to(); + + if (arg_type->array_type() != NULL + && arg_type->array_type()->length() != NULL) + return true; + + if (this->code_ == BUILTIN_LEN && arg_type->is_string_type()) + { + this->seen_ = true; + bool ret = arg->is_constant(); + this->seen_ = false; + return ret; + } + } + break; + + case BUILTIN_SIZEOF: + case BUILTIN_ALIGNOF: + return this->one_arg() != NULL; + + case BUILTIN_OFFSETOF: + { + Expression* arg = this->one_arg(); + if (arg == NULL) + return false; + return arg->field_reference_expression() != NULL; + } + + case BUILTIN_COMPLEX: + { + const Expression_list* args = this->args(); + if (args != NULL && args->size() == 2) + return args->front()->is_constant() && args->back()->is_constant(); + } + break; + + case BUILTIN_REAL: + case BUILTIN_IMAG: + { + Expression* arg = this->one_arg(); + return arg != NULL && arg->is_constant(); + } + + default: + break; + } + + return false; +} + +// Return an integer constant value if possible. + +bool +Builtin_call_expression::do_integer_constant_value(bool iota_is_constant, + mpz_t val, + Type** ptype) const +{ + if (this->code_ == BUILTIN_LEN + || this->code_ == BUILTIN_CAP) + { + Expression* arg = this->one_arg(); + if (arg == NULL) + return false; + Type* arg_type = arg->type(); + + if (this->code_ == BUILTIN_LEN && arg_type->is_string_type()) + { + std::string sval; + if (arg->string_constant_value(&sval)) + { + mpz_set_ui(val, sval.length()); + *ptype = Type::lookup_integer_type("int"); + return true; + } + } + + if (arg_type->points_to() != NULL + && arg_type->points_to()->array_type() != NULL + && !arg_type->points_to()->is_open_array_type()) + arg_type = arg_type->points_to(); + + if (arg_type->array_type() != NULL + && arg_type->array_type()->length() != NULL) + { + if (this->seen_) + return false; + Expression* e = arg_type->array_type()->length(); + this->seen_ = true; + bool r = e->integer_constant_value(iota_is_constant, val, ptype); + this->seen_ = false; + if (r) + { + *ptype = Type::lookup_integer_type("int"); + return true; + } + } + } + else if (this->code_ == BUILTIN_SIZEOF + || this->code_ == BUILTIN_ALIGNOF) + { + Expression* arg = this->one_arg(); + if (arg == NULL) + return false; + Type* arg_type = arg->type(); + if (arg_type->is_error_type() || arg_type->is_undefined()) + return false; + if (arg_type->is_abstract()) + return false; + if (arg_type->named_type() != NULL) + arg_type->named_type()->convert(this->gogo_); + tree arg_type_tree = arg_type->get_tree(this->gogo_); + if (arg_type_tree == error_mark_node) + return false; + unsigned long val_long; + if (this->code_ == BUILTIN_SIZEOF) + { + tree type_size = TYPE_SIZE_UNIT(arg_type_tree); + gcc_assert(TREE_CODE(type_size) == INTEGER_CST); + if (TREE_INT_CST_HIGH(type_size) != 0) + return false; + unsigned HOST_WIDE_INT val_wide = TREE_INT_CST_LOW(type_size); + val_long = static_cast<unsigned long>(val_wide); + if (val_long != val_wide) + return false; + } + else if (this->code_ == BUILTIN_ALIGNOF) + { + if (arg->field_reference_expression() == NULL) + val_long = go_type_alignment(arg_type_tree); + else + { + // Calling unsafe.Alignof(s.f) returns the alignment of + // the type of f when it is used as a field in a struct. + val_long = go_field_alignment(arg_type_tree); + } + } + else + gcc_unreachable(); + mpz_set_ui(val, val_long); + *ptype = NULL; + return true; + } + else if (this->code_ == BUILTIN_OFFSETOF) + { + Expression* arg = this->one_arg(); + if (arg == NULL) + return false; + Field_reference_expression* farg = arg->field_reference_expression(); + if (farg == NULL) + return false; + Expression* struct_expr = farg->expr(); + Type* st = struct_expr->type(); + if (st->struct_type() == NULL) + return false; + if (st->named_type() != NULL) + st->named_type()->convert(this->gogo_); + tree struct_tree = st->get_tree(this->gogo_); + gcc_assert(TREE_CODE(struct_tree) == RECORD_TYPE); + tree field = TYPE_FIELDS(struct_tree); + for (unsigned int index = farg->field_index(); index > 0; --index) + { + field = DECL_CHAIN(field); + gcc_assert(field != NULL_TREE); + } + HOST_WIDE_INT offset_wide = int_byte_position (field); + if (offset_wide < 0) + return false; + unsigned long offset_long = static_cast<unsigned long>(offset_wide); + if (offset_long != static_cast<unsigned HOST_WIDE_INT>(offset_wide)) + return false; + mpz_set_ui(val, offset_long); + return true; + } + return false; +} + +// Return a floating point constant value if possible. + +bool +Builtin_call_expression::do_float_constant_value(mpfr_t val, + Type** ptype) const +{ + if (this->code_ == BUILTIN_REAL || this->code_ == BUILTIN_IMAG) + { + Expression* arg = this->one_arg(); + if (arg == NULL) + return false; + + mpfr_t real; + mpfr_t imag; + mpfr_init(real); + mpfr_init(imag); + + bool ret = false; + Type* type; + if (arg->complex_constant_value(real, imag, &type)) + { + if (this->code_ == BUILTIN_REAL) + mpfr_set(val, real, GMP_RNDN); + else + mpfr_set(val, imag, GMP_RNDN); + *ptype = Builtin_call_expression::real_imag_type(type); + ret = true; + } + + mpfr_clear(real); + mpfr_clear(imag); + return ret; + } + + return false; +} + +// Return a complex constant value if possible. + +bool +Builtin_call_expression::do_complex_constant_value(mpfr_t real, mpfr_t imag, + Type** ptype) const +{ + if (this->code_ == BUILTIN_COMPLEX) + { + const Expression_list* args = this->args(); + if (args == NULL || args->size() != 2) + return false; + + mpfr_t r; + mpfr_init(r); + Type* rtype; + if (!args->front()->float_constant_value(r, &rtype)) + { + mpfr_clear(r); + return false; + } + + mpfr_t i; + mpfr_init(i); + + bool ret = false; + Type* itype; + if (args->back()->float_constant_value(i, &itype) + && Type::are_identical(rtype, itype, false, NULL)) + { + mpfr_set(real, r, GMP_RNDN); + mpfr_set(imag, i, GMP_RNDN); + *ptype = Builtin_call_expression::complex_type(rtype); + ret = true; + } + + mpfr_clear(r); + mpfr_clear(i); + + return ret; + } + + return false; +} + +// Return the type. + +Type* +Builtin_call_expression::do_type() +{ + switch (this->code_) + { + case BUILTIN_INVALID: + default: + gcc_unreachable(); + + case BUILTIN_NEW: + case BUILTIN_MAKE: + { + const Expression_list* args = this->args(); + if (args == NULL || args->empty()) + return Type::make_error_type(); + return Type::make_pointer_type(args->front()->type()); + } + + case BUILTIN_CAP: + case BUILTIN_COPY: + case BUILTIN_LEN: + case BUILTIN_ALIGNOF: + case BUILTIN_OFFSETOF: + case BUILTIN_SIZEOF: + return Type::lookup_integer_type("int"); + + case BUILTIN_CLOSE: + case BUILTIN_PANIC: + case BUILTIN_PRINT: + case BUILTIN_PRINTLN: + return Type::make_void_type(); + + case BUILTIN_CLOSED: + return Type::lookup_bool_type(); + + case BUILTIN_RECOVER: + return Type::make_interface_type(NULL, BUILTINS_LOCATION); + + case BUILTIN_APPEND: + { + const Expression_list* args = this->args(); + if (args == NULL || args->empty()) + return Type::make_error_type(); + return args->front()->type(); + } + + case BUILTIN_REAL: + case BUILTIN_IMAG: + { + Expression* arg = this->one_arg(); + if (arg == NULL) + return Type::make_error_type(); + Type* t = arg->type(); + if (t->is_abstract()) + t = t->make_non_abstract_type(); + t = Builtin_call_expression::real_imag_type(t); + if (t == NULL) + t = Type::make_error_type(); + return t; + } + + case BUILTIN_COMPLEX: + { + const Expression_list* args = this->args(); + if (args == NULL || args->size() != 2) + return Type::make_error_type(); + Type* t = args->front()->type(); + if (t->is_abstract()) + { + t = args->back()->type(); + if (t->is_abstract()) + t = t->make_non_abstract_type(); + } + t = Builtin_call_expression::complex_type(t); + if (t == NULL) + t = Type::make_error_type(); + return t; + } + } +} + +// Determine the type. + +void +Builtin_call_expression::do_determine_type(const Type_context* context) +{ + if (!this->determining_types()) + return; + + this->fn()->determine_type_no_context(); + + const Expression_list* args = this->args(); + + bool is_print; + Type* arg_type = NULL; + switch (this->code_) + { + case BUILTIN_PRINT: + case BUILTIN_PRINTLN: + // Do not force a large integer constant to "int". + is_print = true; + break; + + case BUILTIN_REAL: + case BUILTIN_IMAG: + arg_type = Builtin_call_expression::complex_type(context->type); + is_print = false; + break; + + case BUILTIN_COMPLEX: + { + // For the complex function the type of one operand can + // determine the type of the other, as in a binary expression. + arg_type = Builtin_call_expression::real_imag_type(context->type); + if (args != NULL && args->size() == 2) + { + Type* t1 = args->front()->type(); + Type* t2 = args->front()->type(); + if (!t1->is_abstract()) + arg_type = t1; + else if (!t2->is_abstract()) + arg_type = t2; + } + is_print = false; + } + break; + + default: + is_print = false; + break; + } + + if (args != NULL) + { + for (Expression_list::const_iterator pa = args->begin(); + pa != args->end(); + ++pa) + { + Type_context subcontext; + subcontext.type = arg_type; + + if (is_print) + { + // We want to print large constants, we so can't just + // use the appropriate nonabstract type. Use uint64 for + // an integer if we know it is nonnegative, otherwise + // use int64 for a integer, otherwise use float64 for a + // float or complex128 for a complex. + Type* want_type = NULL; + Type* atype = (*pa)->type(); + if (atype->is_abstract()) + { + if (atype->integer_type() != NULL) + { + mpz_t val; + mpz_init(val); + Type* dummy; + if (this->integer_constant_value(true, val, &dummy) + && mpz_sgn(val) >= 0) + want_type = Type::lookup_integer_type("uint64"); + else + want_type = Type::lookup_integer_type("int64"); + mpz_clear(val); + } + else if (atype->float_type() != NULL) + want_type = Type::lookup_float_type("float64"); + else if (atype->complex_type() != NULL) + want_type = Type::lookup_complex_type("complex128"); + else if (atype->is_abstract_string_type()) + want_type = Type::lookup_string_type(); + else if (atype->is_abstract_boolean_type()) + want_type = Type::lookup_bool_type(); + else + gcc_unreachable(); + subcontext.type = want_type; + } + } + + (*pa)->determine_type(&subcontext); + } + } +} + +// If there is exactly one argument, return true. Otherwise give an +// error message and return false. + +bool +Builtin_call_expression::check_one_arg() +{ + const Expression_list* args = this->args(); + if (args == NULL || args->size() < 1) + { + this->report_error(_("not enough arguments")); + return false; + } + else if (args->size() > 1) + { + this->report_error(_("too many arguments")); + return false; + } + if (args->front()->is_error_expression() + || args->front()->type()->is_error_type() + || args->front()->type()->is_undefined()) + { + this->set_is_error(); + return false; + } + return true; +} + +// Check argument types for a builtin function. + +void +Builtin_call_expression::do_check_types(Gogo*) +{ + switch (this->code_) + { + case BUILTIN_INVALID: + case BUILTIN_NEW: + case BUILTIN_MAKE: + return; + + case BUILTIN_LEN: + case BUILTIN_CAP: + { + // The single argument may be either a string or an array or a + // map or a channel, or a pointer to a closed array. + if (this->check_one_arg()) + { + Type* arg_type = this->one_arg()->type(); + if (arg_type->points_to() != NULL + && arg_type->points_to()->array_type() != NULL + && !arg_type->points_to()->is_open_array_type()) + arg_type = arg_type->points_to(); + if (this->code_ == BUILTIN_CAP) + { + if (!arg_type->is_error_type() + && arg_type->array_type() == NULL + && arg_type->channel_type() == NULL) + this->report_error(_("argument must be array or slice " + "or channel")); + } + else + { + if (!arg_type->is_error_type() + && !arg_type->is_string_type() + && arg_type->array_type() == NULL + && arg_type->map_type() == NULL + && arg_type->channel_type() == NULL) + this->report_error(_("argument must be string or " + "array or slice or map or channel")); + } + } + } + break; + + case BUILTIN_PRINT: + case BUILTIN_PRINTLN: + { + const Expression_list* args = this->args(); + if (args == NULL) + { + if (this->code_ == BUILTIN_PRINT) + warning_at(this->location(), 0, + "no arguments for builtin function %<%s%>", + (this->code_ == BUILTIN_PRINT + ? "print" + : "println")); + } + else + { + for (Expression_list::const_iterator p = args->begin(); + p != args->end(); + ++p) + { + Type* type = (*p)->type(); + if (type->is_error_type() + || type->is_string_type() + || type->integer_type() != NULL + || type->float_type() != NULL + || type->complex_type() != NULL + || type->is_boolean_type() + || type->points_to() != NULL + || type->interface_type() != NULL + || type->channel_type() != NULL + || type->map_type() != NULL + || type->function_type() != NULL + || type->is_open_array_type()) + ; + else + this->report_error(_("unsupported argument type to " + "builtin function")); + } + } + } + break; + + case BUILTIN_CLOSE: + case BUILTIN_CLOSED: + if (this->check_one_arg()) + { + if (this->one_arg()->type()->channel_type() == NULL) + this->report_error(_("argument must be channel")); + } + break; + + case BUILTIN_PANIC: + case BUILTIN_SIZEOF: + case BUILTIN_ALIGNOF: + this->check_one_arg(); + break; + + case BUILTIN_RECOVER: + if (this->args() != NULL && !this->args()->empty()) + this->report_error(_("too many arguments")); + break; + + case BUILTIN_OFFSETOF: + if (this->check_one_arg()) + { + Expression* arg = this->one_arg(); + if (arg->field_reference_expression() == NULL) + this->report_error(_("argument must be a field reference")); + } + break; + + case BUILTIN_COPY: + { + const Expression_list* args = this->args(); + if (args == NULL || args->size() < 2) + { + this->report_error(_("not enough arguments")); + break; + } + else if (args->size() > 2) + { + this->report_error(_("too many arguments")); + break; + } + Type* arg1_type = args->front()->type(); + Type* arg2_type = args->back()->type(); + if (arg1_type->is_error_type() || arg2_type->is_error_type()) + break; + + Type* e1; + if (arg1_type->is_open_array_type()) + e1 = arg1_type->array_type()->element_type(); + else + { + this->report_error(_("left argument must be a slice")); + break; + } + + Type* e2; + if (arg2_type->is_open_array_type()) + e2 = arg2_type->array_type()->element_type(); + else if (arg2_type->is_string_type()) + e2 = Type::lookup_integer_type("uint8"); + else + { + this->report_error(_("right argument must be a slice or a string")); + break; + } + + if (!Type::are_identical(e1, e2, true, NULL)) + this->report_error(_("element types must be the same")); + } + break; + + case BUILTIN_APPEND: + { + const Expression_list* args = this->args(); + if (args == NULL || args->size() < 2) + { + this->report_error(_("not enough arguments")); + break; + } + if (args->size() > 2) + { + this->report_error(_("too many arguments")); + break; + } + std::string reason; + if (!Type::are_assignable(args->front()->type(), args->back()->type(), + &reason)) + { + if (reason.empty()) + this->report_error(_("arguments 1 and 2 have different types")); + else + { + error_at(this->location(), + "arguments 1 and 2 have different types (%s)", + reason.c_str()); + this->set_is_error(); + } + } + break; + } + + case BUILTIN_REAL: + case BUILTIN_IMAG: + if (this->check_one_arg()) + { + if (this->one_arg()->type()->complex_type() == NULL) + this->report_error(_("argument must have complex type")); + } + break; + + case BUILTIN_COMPLEX: + { + const Expression_list* args = this->args(); + if (args == NULL || args->size() < 2) + this->report_error(_("not enough arguments")); + else if (args->size() > 2) + this->report_error(_("too many arguments")); + else if (args->front()->is_error_expression() + || args->front()->type()->is_error_type() + || args->back()->is_error_expression() + || args->back()->type()->is_error_type()) + this->set_is_error(); + else if (!Type::are_identical(args->front()->type(), + args->back()->type(), true, NULL)) + this->report_error(_("complex arguments must have identical types")); + else if (args->front()->type()->float_type() == NULL) + this->report_error(_("complex arguments must have " + "floating-point type")); + } + break; + + default: + gcc_unreachable(); + } +} + +// Return the tree for a builtin function. + +tree +Builtin_call_expression::do_get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + source_location location = this->location(); + switch (this->code_) + { + case BUILTIN_INVALID: + case BUILTIN_NEW: + case BUILTIN_MAKE: + gcc_unreachable(); + + case BUILTIN_LEN: + case BUILTIN_CAP: + { + const Expression_list* args = this->args(); + gcc_assert(args != NULL && args->size() == 1); + Expression* arg = *args->begin(); + Type* arg_type = arg->type(); + + if (this->seen_) + { + gcc_assert(saw_errors()); + return error_mark_node; + } + this->seen_ = true; + + tree arg_tree = arg->get_tree(context); + + this->seen_ = false; + + if (arg_tree == error_mark_node) + return error_mark_node; + + if (arg_type->points_to() != NULL) + { + arg_type = arg_type->points_to(); + gcc_assert(arg_type->array_type() != NULL + && !arg_type->is_open_array_type()); + gcc_assert(POINTER_TYPE_P(TREE_TYPE(arg_tree))); + arg_tree = build_fold_indirect_ref(arg_tree); + } + + tree val_tree; + if (this->code_ == BUILTIN_LEN) + { + if (arg_type->is_string_type()) + val_tree = String_type::length_tree(gogo, arg_tree); + else if (arg_type->array_type() != NULL) + { + if (this->seen_) + { + gcc_assert(saw_errors()); + return error_mark_node; + } + this->seen_ = true; + val_tree = arg_type->array_type()->length_tree(gogo, arg_tree); + this->seen_ = false; + } + else if (arg_type->map_type() != NULL) + { + static tree map_len_fndecl; + val_tree = Gogo::call_builtin(&map_len_fndecl, + location, + "__go_map_len", + 1, + sizetype, + arg_type->get_tree(gogo), + arg_tree); + } + else if (arg_type->channel_type() != NULL) + { + static tree chan_len_fndecl; + val_tree = Gogo::call_builtin(&chan_len_fndecl, + location, + "__go_chan_len", + 1, + sizetype, + arg_type->get_tree(gogo), + arg_tree); + } + else + gcc_unreachable(); + } + else + { + if (arg_type->array_type() != NULL) + { + if (this->seen_) + { + gcc_assert(saw_errors()); + return error_mark_node; + } + this->seen_ = true; + val_tree = arg_type->array_type()->capacity_tree(gogo, + arg_tree); + this->seen_ = false; + } + else if (arg_type->channel_type() != NULL) + { + static tree chan_cap_fndecl; + val_tree = Gogo::call_builtin(&chan_cap_fndecl, + location, + "__go_chan_cap", + 1, + sizetype, + arg_type->get_tree(gogo), + arg_tree); + } + else + gcc_unreachable(); + } + + if (val_tree == error_mark_node) + return error_mark_node; + + tree type_tree = Type::lookup_integer_type("int")->get_tree(gogo); + if (type_tree == TREE_TYPE(val_tree)) + return val_tree; + else + return fold(convert_to_integer(type_tree, val_tree)); + } + + case BUILTIN_PRINT: + case BUILTIN_PRINTLN: + { + const bool is_ln = this->code_ == BUILTIN_PRINTLN; + tree stmt_list = NULL_TREE; + + const Expression_list* call_args = this->args(); + if (call_args != NULL) + { + for (Expression_list::const_iterator p = call_args->begin(); + p != call_args->end(); + ++p) + { + if (is_ln && p != call_args->begin()) + { + static tree print_space_fndecl; + tree call = Gogo::call_builtin(&print_space_fndecl, + location, + "__go_print_space", + 0, + void_type_node); + if (call == error_mark_node) + return error_mark_node; + append_to_statement_list(call, &stmt_list); + } + + Type* type = (*p)->type(); + + tree arg = (*p)->get_tree(context); + if (arg == error_mark_node) + return error_mark_node; + + tree* pfndecl; + const char* fnname; + if (type->is_string_type()) + { + static tree print_string_fndecl; + pfndecl = &print_string_fndecl; + fnname = "__go_print_string"; + } + else if (type->integer_type() != NULL + && type->integer_type()->is_unsigned()) + { + static tree print_uint64_fndecl; + pfndecl = &print_uint64_fndecl; + fnname = "__go_print_uint64"; + Type* itype = Type::lookup_integer_type("uint64"); + arg = fold_convert_loc(location, itype->get_tree(gogo), + arg); + } + else if (type->integer_type() != NULL) + { + static tree print_int64_fndecl; + pfndecl = &print_int64_fndecl; + fnname = "__go_print_int64"; + Type* itype = Type::lookup_integer_type("int64"); + arg = fold_convert_loc(location, itype->get_tree(gogo), + arg); + } + else if (type->float_type() != NULL) + { + static tree print_double_fndecl; + pfndecl = &print_double_fndecl; + fnname = "__go_print_double"; + arg = fold_convert_loc(location, double_type_node, arg); + } + else if (type->complex_type() != NULL) + { + static tree print_complex_fndecl; + pfndecl = &print_complex_fndecl; + fnname = "__go_print_complex"; + arg = fold_convert_loc(location, complex_double_type_node, + arg); + } + else if (type->is_boolean_type()) + { + static tree print_bool_fndecl; + pfndecl = &print_bool_fndecl; + fnname = "__go_print_bool"; + } + else if (type->points_to() != NULL + || type->channel_type() != NULL + || type->map_type() != NULL + || type->function_type() != NULL) + { + static tree print_pointer_fndecl; + pfndecl = &print_pointer_fndecl; + fnname = "__go_print_pointer"; + arg = fold_convert_loc(location, ptr_type_node, arg); + } + else if (type->interface_type() != NULL) + { + if (type->interface_type()->is_empty()) + { + static tree print_empty_interface_fndecl; + pfndecl = &print_empty_interface_fndecl; + fnname = "__go_print_empty_interface"; + } + else + { + static tree print_interface_fndecl; + pfndecl = &print_interface_fndecl; + fnname = "__go_print_interface"; + } + } + else if (type->is_open_array_type()) + { + static tree print_slice_fndecl; + pfndecl = &print_slice_fndecl; + fnname = "__go_print_slice"; + } + else + gcc_unreachable(); + + tree call = Gogo::call_builtin(pfndecl, + location, + fnname, + 1, + void_type_node, + TREE_TYPE(arg), + arg); + if (call == error_mark_node) + return error_mark_node; + append_to_statement_list(call, &stmt_list); + } + } + + if (is_ln) + { + static tree print_nl_fndecl; + tree call = Gogo::call_builtin(&print_nl_fndecl, + location, + "__go_print_nl", + 0, + void_type_node); + if (call == error_mark_node) + return error_mark_node; + append_to_statement_list(call, &stmt_list); + } + + return stmt_list; + } + + case BUILTIN_PANIC: + { + const Expression_list* args = this->args(); + gcc_assert(args != NULL && args->size() == 1); + Expression* arg = args->front(); + tree arg_tree = arg->get_tree(context); + if (arg_tree == error_mark_node) + return error_mark_node; + Type *empty = Type::make_interface_type(NULL, BUILTINS_LOCATION); + arg_tree = Expression::convert_for_assignment(context, empty, + arg->type(), + arg_tree, location); + static tree panic_fndecl; + tree call = Gogo::call_builtin(&panic_fndecl, + location, + "__go_panic", + 1, + void_type_node, + TREE_TYPE(arg_tree), + arg_tree); + if (call == error_mark_node) + return error_mark_node; + // This function will throw an exception. + TREE_NOTHROW(panic_fndecl) = 0; + // This function will not return. + TREE_THIS_VOLATILE(panic_fndecl) = 1; + return call; + } + + case BUILTIN_RECOVER: + { + // The argument is set when building recover thunks. It's a + // boolean value which is true if we can recover a value now. + const Expression_list* args = this->args(); + gcc_assert(args != NULL && args->size() == 1); + Expression* arg = args->front(); + tree arg_tree = arg->get_tree(context); + if (arg_tree == error_mark_node) + return error_mark_node; + + Type *empty = Type::make_interface_type(NULL, BUILTINS_LOCATION); + tree empty_tree = empty->get_tree(context->gogo()); + + Type* nil_type = Type::make_nil_type(); + Expression* nil = Expression::make_nil(location); + tree nil_tree = nil->get_tree(context); + tree empty_nil_tree = Expression::convert_for_assignment(context, + empty, + nil_type, + nil_tree, + location); + + // We need to handle a deferred call to recover specially, + // because it changes whether it can recover a panic or not. + // See test7 in test/recover1.go. + tree call; + if (this->is_deferred()) + { + static tree deferred_recover_fndecl; + call = Gogo::call_builtin(&deferred_recover_fndecl, + location, + "__go_deferred_recover", + 0, + empty_tree); + } + else + { + static tree recover_fndecl; + call = Gogo::call_builtin(&recover_fndecl, + location, + "__go_recover", + 0, + empty_tree); + } + if (call == error_mark_node) + return error_mark_node; + return fold_build3_loc(location, COND_EXPR, empty_tree, arg_tree, + call, empty_nil_tree); + } + + case BUILTIN_CLOSE: + case BUILTIN_CLOSED: + { + const Expression_list* args = this->args(); + gcc_assert(args != NULL && args->size() == 1); + Expression* arg = args->front(); + tree arg_tree = arg->get_tree(context); + if (arg_tree == error_mark_node) + return error_mark_node; + if (this->code_ == BUILTIN_CLOSE) + { + static tree close_fndecl; + return Gogo::call_builtin(&close_fndecl, + location, + "__go_builtin_close", + 1, + void_type_node, + TREE_TYPE(arg_tree), + arg_tree); + } + else + { + static tree closed_fndecl; + return Gogo::call_builtin(&closed_fndecl, + location, + "__go_builtin_closed", + 1, + boolean_type_node, + TREE_TYPE(arg_tree), + arg_tree); + } + } + + case BUILTIN_SIZEOF: + case BUILTIN_OFFSETOF: + case BUILTIN_ALIGNOF: + { + mpz_t val; + mpz_init(val); + Type* dummy; + bool b = this->integer_constant_value(true, val, &dummy); + if (!b) + { + gcc_assert(saw_errors()); + return error_mark_node; + } + tree type = Type::lookup_integer_type("int")->get_tree(gogo); + tree ret = Expression::integer_constant_tree(val, type); + mpz_clear(val); + return ret; + } + + case BUILTIN_COPY: + { + const Expression_list* args = this->args(); + gcc_assert(args != NULL && args->size() == 2); + Expression* arg1 = args->front(); + Expression* arg2 = args->back(); + + tree arg1_tree = arg1->get_tree(context); + tree arg2_tree = arg2->get_tree(context); + if (arg1_tree == error_mark_node || arg2_tree == error_mark_node) + return error_mark_node; + + Type* arg1_type = arg1->type(); + Array_type* at = arg1_type->array_type(); + arg1_tree = save_expr(arg1_tree); + tree arg1_val = at->value_pointer_tree(gogo, arg1_tree); + tree arg1_len = at->length_tree(gogo, arg1_tree); + if (arg1_val == error_mark_node || arg1_len == error_mark_node) + return error_mark_node; + + Type* arg2_type = arg2->type(); + tree arg2_val; + tree arg2_len; + if (arg2_type->is_open_array_type()) + { + at = arg2_type->array_type(); + arg2_tree = save_expr(arg2_tree); + arg2_val = at->value_pointer_tree(gogo, arg2_tree); + arg2_len = at->length_tree(gogo, arg2_tree); + } + else + { + arg2_tree = save_expr(arg2_tree); + arg2_val = String_type::bytes_tree(gogo, arg2_tree); + arg2_len = String_type::length_tree(gogo, arg2_tree); + } + if (arg2_val == error_mark_node || arg2_len == error_mark_node) + return error_mark_node; + + arg1_len = save_expr(arg1_len); + arg2_len = save_expr(arg2_len); + tree len = fold_build3_loc(location, COND_EXPR, TREE_TYPE(arg1_len), + fold_build2_loc(location, LT_EXPR, + boolean_type_node, + arg1_len, arg2_len), + arg1_len, arg2_len); + len = save_expr(len); + + Type* element_type = at->element_type(); + tree element_type_tree = element_type->get_tree(gogo); + if (element_type_tree == error_mark_node) + return error_mark_node; + tree element_size = TYPE_SIZE_UNIT(element_type_tree); + tree bytecount = fold_convert_loc(location, TREE_TYPE(element_size), + len); + bytecount = fold_build2_loc(location, MULT_EXPR, + TREE_TYPE(element_size), + bytecount, element_size); + bytecount = fold_convert_loc(location, size_type_node, bytecount); + + arg1_val = fold_convert_loc(location, ptr_type_node, arg1_val); + arg2_val = fold_convert_loc(location, ptr_type_node, arg2_val); + + static tree copy_fndecl; + tree call = Gogo::call_builtin(©_fndecl, + location, + "__go_copy", + 3, + void_type_node, + ptr_type_node, + arg1_val, + ptr_type_node, + arg2_val, + size_type_node, + bytecount); + if (call == error_mark_node) + return error_mark_node; + + return fold_build2_loc(location, COMPOUND_EXPR, TREE_TYPE(len), + call, len); + } + + case BUILTIN_APPEND: + { + const Expression_list* args = this->args(); + gcc_assert(args != NULL && args->size() == 2); + Expression* arg1 = args->front(); + Expression* arg2 = args->back(); + + tree arg1_tree = arg1->get_tree(context); + tree arg2_tree = arg2->get_tree(context); + if (arg1_tree == error_mark_node || arg2_tree == error_mark_node) + return error_mark_node; + + Array_type* at = arg1->type()->array_type(); + Type* element_type = at->element_type(); + + arg2_tree = Expression::convert_for_assignment(context, at, + arg2->type(), + arg2_tree, + location); + if (arg2_tree == error_mark_node) + return error_mark_node; + + arg2_tree = save_expr(arg2_tree); + tree arg2_val = at->value_pointer_tree(gogo, arg2_tree); + tree arg2_len = at->length_tree(gogo, arg2_tree); + if (arg2_val == error_mark_node || arg2_len == error_mark_node) + return error_mark_node; + arg2_val = fold_convert_loc(location, ptr_type_node, arg2_val); + arg2_len = fold_convert_loc(location, size_type_node, arg2_len); + + tree element_type_tree = element_type->get_tree(gogo); + if (element_type_tree == error_mark_node) + return error_mark_node; + tree element_size = TYPE_SIZE_UNIT(element_type_tree); + element_size = fold_convert_loc(location, size_type_node, + element_size); + + // We rebuild the decl each time since the slice types may + // change. + tree append_fndecl = NULL_TREE; + return Gogo::call_builtin(&append_fndecl, + location, + "__go_append", + 4, + TREE_TYPE(arg1_tree), + TREE_TYPE(arg1_tree), + arg1_tree, + ptr_type_node, + arg2_val, + size_type_node, + arg2_len, + size_type_node, + element_size); + } + + case BUILTIN_REAL: + case BUILTIN_IMAG: + { + const Expression_list* args = this->args(); + gcc_assert(args != NULL && args->size() == 1); + Expression* arg = args->front(); + tree arg_tree = arg->get_tree(context); + if (arg_tree == error_mark_node) + return error_mark_node; + gcc_assert(COMPLEX_FLOAT_TYPE_P(TREE_TYPE(arg_tree))); + if (this->code_ == BUILTIN_REAL) + return fold_build1_loc(location, REALPART_EXPR, + TREE_TYPE(TREE_TYPE(arg_tree)), + arg_tree); + else + return fold_build1_loc(location, IMAGPART_EXPR, + TREE_TYPE(TREE_TYPE(arg_tree)), + arg_tree); + } + + case BUILTIN_COMPLEX: + { + const Expression_list* args = this->args(); + gcc_assert(args != NULL && args->size() == 2); + tree r = args->front()->get_tree(context); + tree i = args->back()->get_tree(context); + if (r == error_mark_node || i == error_mark_node) + return error_mark_node; + gcc_assert(TYPE_MAIN_VARIANT(TREE_TYPE(r)) + == TYPE_MAIN_VARIANT(TREE_TYPE(i))); + gcc_assert(SCALAR_FLOAT_TYPE_P(TREE_TYPE(r))); + return fold_build2_loc(location, COMPLEX_EXPR, + build_complex_type(TREE_TYPE(r)), + r, i); + } + + default: + gcc_unreachable(); + } +} + +// We have to support exporting a builtin call expression, because +// code can set a constant to the result of a builtin expression. + +void +Builtin_call_expression::do_export(Export* exp) const +{ + bool ok = false; + + mpz_t val; + mpz_init(val); + Type* dummy; + if (this->integer_constant_value(true, val, &dummy)) + { + Integer_expression::export_integer(exp, val); + ok = true; + } + mpz_clear(val); + + if (!ok) + { + mpfr_t fval; + mpfr_init(fval); + if (this->float_constant_value(fval, &dummy)) + { + Float_expression::export_float(exp, fval); + ok = true; + } + mpfr_clear(fval); + } + + if (!ok) + { + mpfr_t real; + mpfr_t imag; + mpfr_init(real); + mpfr_init(imag); + if (this->complex_constant_value(real, imag, &dummy)) + { + Complex_expression::export_complex(exp, real, imag); + ok = true; + } + mpfr_clear(real); + mpfr_clear(imag); + } + + if (!ok) + { + error_at(this->location(), "value is not constant"); + return; + } + + // A trailing space lets us reliably identify the end of the number. + exp->write_c_string(" "); +} + +// Class Call_expression. + +// Traversal. + +int +Call_expression::do_traverse(Traverse* traverse) +{ + if (Expression::traverse(&this->fn_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (this->args_ != NULL) + { + if (this->args_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +// Lower a call statement. + +Expression* +Call_expression::do_lower(Gogo* gogo, Named_object* function, int) +{ + // A type case can look like a function call. + if (this->fn_->is_type_expression() + && this->args_ != NULL + && this->args_->size() == 1) + return Expression::make_cast(this->fn_->type(), this->args_->front(), + this->location()); + + // Recognize a call to a builtin function. + Func_expression* fne = this->fn_->func_expression(); + if (fne != NULL + && fne->named_object()->is_function_declaration() + && fne->named_object()->func_declaration_value()->type()->is_builtin()) + return new Builtin_call_expression(gogo, this->fn_, this->args_, + this->is_varargs_, this->location()); + + // Handle an argument which is a call to a function which returns + // multiple results. + if (this->args_ != NULL + && this->args_->size() == 1 + && this->args_->front()->call_expression() != NULL + && this->fn_->type()->function_type() != NULL) + { + Function_type* fntype = this->fn_->type()->function_type(); + size_t rc = this->args_->front()->call_expression()->result_count(); + if (rc > 1 + && fntype->parameters() != NULL + && (fntype->parameters()->size() == rc + || (fntype->is_varargs() + && fntype->parameters()->size() - 1 <= rc))) + { + Call_expression* call = this->args_->front()->call_expression(); + Expression_list* args = new Expression_list; + for (size_t i = 0; i < rc; ++i) + args->push_back(Expression::make_call_result(call, i)); + // We can't return a new call expression here, because this + // one may be referenced by Call_result expressions. We + // also can't delete the old arguments, because we may still + // traverse them somewhere up the call stack. FIXME. + this->args_ = args; + } + } + + // Handle a call to a varargs function by packaging up the extra + // parameters. + if (this->fn_->type()->function_type() != NULL + && this->fn_->type()->function_type()->is_varargs()) + { + Function_type* fntype = this->fn_->type()->function_type(); + const Typed_identifier_list* parameters = fntype->parameters(); + gcc_assert(parameters != NULL && !parameters->empty()); + Type* varargs_type = parameters->back().type(); + return this->lower_varargs(gogo, function, varargs_type, + parameters->size()); + } + + return this; +} + +// Lower a call to a varargs function. FUNCTION is the function in +// which the call occurs--it's not the function we are calling. +// VARARGS_TYPE is the type of the varargs parameter, a slice type. +// PARAM_COUNT is the number of parameters of the function we are +// calling; the last of these parameters will be the varargs +// parameter. + +Expression* +Call_expression::lower_varargs(Gogo* gogo, Named_object* function, + Type* varargs_type, size_t param_count) +{ + if (this->varargs_are_lowered_) + return this; + + source_location loc = this->location(); + + gcc_assert(param_count > 0); + gcc_assert(varargs_type->is_open_array_type()); + + size_t arg_count = this->args_ == NULL ? 0 : this->args_->size(); + if (arg_count < param_count - 1) + { + // Not enough arguments; will be caught in check_types. + return this; + } + + Expression_list* old_args = this->args_; + Expression_list* new_args = new Expression_list(); + bool push_empty_arg = false; + if (old_args == NULL || old_args->empty()) + { + gcc_assert(param_count == 1); + push_empty_arg = true; + } + else + { + Expression_list::const_iterator pa; + int i = 1; + for (pa = old_args->begin(); pa != old_args->end(); ++pa, ++i) + { + if (static_cast<size_t>(i) == param_count) + break; + new_args->push_back(*pa); + } + + // We have reached the varargs parameter. + + bool issued_error = false; + if (pa == old_args->end()) + push_empty_arg = true; + else if (pa + 1 == old_args->end() && this->is_varargs_) + new_args->push_back(*pa); + else if (this->is_varargs_) + { + this->report_error(_("too many arguments")); + return this; + } + else + { + Type* element_type = varargs_type->array_type()->element_type(); + Expression_list* vals = new Expression_list; + for (; pa != old_args->end(); ++pa, ++i) + { + // Check types here so that we get a better message. + Type* patype = (*pa)->type(); + source_location paloc = (*pa)->location(); + if (!this->check_argument_type(i, element_type, patype, + paloc, issued_error)) + continue; + vals->push_back(*pa); + } + Expression* val = + Expression::make_slice_composite_literal(varargs_type, vals, loc); + new_args->push_back(val); + } + } + + if (push_empty_arg) + new_args->push_back(Expression::make_nil(loc)); + + // We can't return a new call expression here, because this one may + // be referenced by Call_result expressions. FIXME. + if (old_args != NULL) + delete old_args; + this->args_ = new_args; + this->varargs_are_lowered_ = true; + + // Lower all the new subexpressions. + Expression* ret = this; + gogo->lower_expression(function, &ret); + gcc_assert(ret == this); + return ret; +} + +// Get the function type. Returns NULL if we don't know the type. If +// this returns NULL, and if_ERROR is true, issues an error. + +Function_type* +Call_expression::get_function_type() const +{ + return this->fn_->type()->function_type(); +} + +// Return the number of values which this call will return. + +size_t +Call_expression::result_count() const +{ + const Function_type* fntype = this->get_function_type(); + if (fntype == NULL) + return 0; + if (fntype->results() == NULL) + return 0; + return fntype->results()->size(); +} + +// Return whether this is a call to the predeclared function recover. + +bool +Call_expression::is_recover_call() const +{ + return this->do_is_recover_call(); +} + +// Set the argument to the recover function. + +void +Call_expression::set_recover_arg(Expression* arg) +{ + this->do_set_recover_arg(arg); +} + +// Virtual functions also implemented by Builtin_call_expression. + +bool +Call_expression::do_is_recover_call() const +{ + return false; +} + +void +Call_expression::do_set_recover_arg(Expression*) +{ + gcc_unreachable(); +} + +// Get the type. + +Type* +Call_expression::do_type() +{ + if (this->type_ != NULL) + return this->type_; + + Type* ret; + Function_type* fntype = this->get_function_type(); + if (fntype == NULL) + return Type::make_error_type(); + + const Typed_identifier_list* results = fntype->results(); + if (results == NULL) + ret = Type::make_void_type(); + else if (results->size() == 1) + ret = results->begin()->type(); + else + ret = Type::make_call_multiple_result_type(this); + + this->type_ = ret; + + return this->type_; +} + +// Determine types for a call expression. We can use the function +// parameter types to set the types of the arguments. + +void +Call_expression::do_determine_type(const Type_context*) +{ + if (!this->determining_types()) + return; + + this->fn_->determine_type_no_context(); + Function_type* fntype = this->get_function_type(); + const Typed_identifier_list* parameters = NULL; + if (fntype != NULL) + parameters = fntype->parameters(); + if (this->args_ != NULL) + { + Typed_identifier_list::const_iterator pt; + if (parameters != NULL) + pt = parameters->begin(); + for (Expression_list::const_iterator pa = this->args_->begin(); + pa != this->args_->end(); + ++pa) + { + if (parameters != NULL && pt != parameters->end()) + { + Type_context subcontext(pt->type(), false); + (*pa)->determine_type(&subcontext); + ++pt; + } + else + (*pa)->determine_type_no_context(); + } + } +} + +// Called when determining types for a Call_expression. Return true +// if we should go ahead, false if they have already been determined. + +bool +Call_expression::determining_types() +{ + if (this->types_are_determined_) + return false; + else + { + this->types_are_determined_ = true; + return true; + } +} + +// Check types for parameter I. + +bool +Call_expression::check_argument_type(int i, const Type* parameter_type, + const Type* argument_type, + source_location argument_location, + bool issued_error) +{ + std::string reason; + if (!Type::are_assignable(parameter_type, argument_type, &reason)) + { + if (!issued_error) + { + if (reason.empty()) + error_at(argument_location, "argument %d has incompatible type", i); + else + error_at(argument_location, + "argument %d has incompatible type (%s)", + i, reason.c_str()); + } + this->set_is_error(); + return false; + } + return true; +} + +// Check types. + +void +Call_expression::do_check_types(Gogo*) +{ + Function_type* fntype = this->get_function_type(); + if (fntype == NULL) + { + if (!this->fn_->type()->is_error_type()) + this->report_error(_("expected function")); + return; + } + + if (fntype->is_method()) + { + // We don't support pointers to methods, so the function has to + // be a bound method expression. + Bound_method_expression* bme = this->fn_->bound_method_expression(); + if (bme == NULL) + { + this->report_error(_("method call without object")); + return; + } + Type* first_arg_type = bme->first_argument()->type(); + if (first_arg_type->points_to() == NULL) + { + // When passing a value, we need to check that we are + // permitted to copy it. + std::string reason; + if (!Type::are_assignable(fntype->receiver()->type(), + first_arg_type, &reason)) + { + if (reason.empty()) + this->report_error(_("incompatible type for receiver")); + else + { + error_at(this->location(), + "incompatible type for receiver (%s)", + reason.c_str()); + this->set_is_error(); + } + } + } + } + + // Note that varargs was handled by the lower_varargs() method, so + // we don't have to worry about it here. + + const Typed_identifier_list* parameters = fntype->parameters(); + if (this->args_ == NULL) + { + if (parameters != NULL && !parameters->empty()) + this->report_error(_("not enough arguments")); + } + else if (parameters == NULL) + this->report_error(_("too many arguments")); + else + { + int i = 0; + Typed_identifier_list::const_iterator pt = parameters->begin(); + for (Expression_list::const_iterator pa = this->args_->begin(); + pa != this->args_->end(); + ++pa, ++pt, ++i) + { + if (pt == parameters->end()) + { + this->report_error(_("too many arguments")); + return; + } + this->check_argument_type(i + 1, pt->type(), (*pa)->type(), + (*pa)->location(), false); + } + if (pt != parameters->end()) + this->report_error(_("not enough arguments")); + } +} + +// Return whether we have to use a temporary variable to ensure that +// we evaluate this call expression in order. If the call returns no +// results then it will inevitably be executed last. If the call +// returns more than one result then it will be used with Call_result +// expressions. So we only have to use a temporary variable if the +// call returns exactly one result. + +bool +Call_expression::do_must_eval_in_order() const +{ + return this->result_count() == 1; +} + +// Get the function and the first argument to use when calling a bound +// method. + +tree +Call_expression::bound_method_function(Translate_context* context, + Bound_method_expression* bound_method, + tree* first_arg_ptr) +{ + Expression* first_argument = bound_method->first_argument(); + tree first_arg = first_argument->get_tree(context); + if (first_arg == error_mark_node) + return error_mark_node; + + // We always pass a pointer to the first argument when calling a + // method. + if (first_argument->type()->points_to() == NULL) + { + tree pointer_to_arg_type = build_pointer_type(TREE_TYPE(first_arg)); + if (TREE_ADDRESSABLE(TREE_TYPE(first_arg)) + || DECL_P(first_arg) + || TREE_CODE(first_arg) == INDIRECT_REF + || TREE_CODE(first_arg) == COMPONENT_REF) + { + first_arg = build_fold_addr_expr(first_arg); + if (DECL_P(first_arg)) + TREE_ADDRESSABLE(first_arg) = 1; + } + else + { + tree tmp = create_tmp_var(TREE_TYPE(first_arg), + get_name(first_arg)); + DECL_IGNORED_P(tmp) = 0; + DECL_INITIAL(tmp) = first_arg; + first_arg = build2(COMPOUND_EXPR, pointer_to_arg_type, + build1(DECL_EXPR, void_type_node, tmp), + build_fold_addr_expr(tmp)); + TREE_ADDRESSABLE(tmp) = 1; + } + if (first_arg == error_mark_node) + return error_mark_node; + } + + Type* fatype = bound_method->first_argument_type(); + if (fatype != NULL) + { + if (fatype->points_to() == NULL) + fatype = Type::make_pointer_type(fatype); + first_arg = fold_convert(fatype->get_tree(context->gogo()), first_arg); + if (first_arg == error_mark_node + || TREE_TYPE(first_arg) == error_mark_node) + return error_mark_node; + } + + *first_arg_ptr = first_arg; + + return bound_method->method()->get_tree(context); +} + +// Get the function and the first argument to use when calling an +// interface method. + +tree +Call_expression::interface_method_function( + Translate_context* context, + Interface_field_reference_expression* interface_method, + tree* first_arg_ptr) +{ + tree expr = interface_method->expr()->get_tree(context); + if (expr == error_mark_node) + return error_mark_node; + expr = save_expr(expr); + tree first_arg = interface_method->get_underlying_object_tree(context, expr); + if (first_arg == error_mark_node) + return error_mark_node; + *first_arg_ptr = first_arg; + return interface_method->get_function_tree(context, expr); +} + +// Build the call expression. + +tree +Call_expression::do_get_tree(Translate_context* context) +{ + if (this->tree_ != NULL_TREE) + return this->tree_; + + Function_type* fntype = this->get_function_type(); + if (fntype == NULL) + return error_mark_node; + + if (this->fn_->is_error_expression()) + return error_mark_node; + + Gogo* gogo = context->gogo(); + source_location location = this->location(); + + Func_expression* func = this->fn_->func_expression(); + Bound_method_expression* bound_method = this->fn_->bound_method_expression(); + Interface_field_reference_expression* interface_method = + this->fn_->interface_field_reference_expression(); + const bool has_closure = func != NULL && func->closure() != NULL; + const bool is_method = bound_method != NULL || interface_method != NULL; + gcc_assert(!fntype->is_method() || is_method); + + int nargs; + tree* args; + if (this->args_ == NULL || this->args_->empty()) + { + nargs = is_method ? 1 : 0; + args = nargs == 0 ? NULL : new tree[nargs]; + } + else + { + const Typed_identifier_list* params = fntype->parameters(); + gcc_assert(params != NULL); + + nargs = this->args_->size(); + int i = is_method ? 1 : 0; + nargs += i; + args = new tree[nargs]; + + Typed_identifier_list::const_iterator pp = params->begin(); + Expression_list::const_iterator pe; + for (pe = this->args_->begin(); + pe != this->args_->end(); + ++pe, ++pp, ++i) + { + gcc_assert(pp != params->end()); + tree arg_val = (*pe)->get_tree(context); + args[i] = Expression::convert_for_assignment(context, + pp->type(), + (*pe)->type(), + arg_val, + location); + if (args[i] == error_mark_node) + { + delete[] args; + return error_mark_node; + } + } + gcc_assert(pp == params->end()); + gcc_assert(i == nargs); + } + + tree rettype = TREE_TYPE(TREE_TYPE(fntype->get_tree(gogo))); + if (rettype == error_mark_node) + { + delete[] args; + return error_mark_node; + } + + tree fn; + if (has_closure) + fn = func->get_tree_without_closure(gogo); + else if (!is_method) + fn = this->fn_->get_tree(context); + else if (bound_method != NULL) + fn = this->bound_method_function(context, bound_method, &args[0]); + else if (interface_method != NULL) + fn = this->interface_method_function(context, interface_method, &args[0]); + else + gcc_unreachable(); + + if (fn == error_mark_node || TREE_TYPE(fn) == error_mark_node) + { + delete[] args; + return error_mark_node; + } + + tree fndecl = fn; + if (TREE_CODE(fndecl) == ADDR_EXPR) + fndecl = TREE_OPERAND(fndecl, 0); + + // Add a type cast in case the type of the function is a recursive + // type which refers to itself. + if (!DECL_P(fndecl) || !DECL_IS_BUILTIN(fndecl)) + { + tree fnt = fntype->get_tree(gogo); + if (fnt == error_mark_node) + return error_mark_node; + fn = fold_convert_loc(location, fnt, fn); + } + + // This is to support builtin math functions when using 80387 math. + tree excess_type = NULL_TREE; + if (DECL_P(fndecl) + && DECL_IS_BUILTIN(fndecl) + && DECL_BUILT_IN_CLASS(fndecl) == BUILT_IN_NORMAL + && nargs > 0 + && ((SCALAR_FLOAT_TYPE_P(rettype) + && SCALAR_FLOAT_TYPE_P(TREE_TYPE(args[0]))) + || (COMPLEX_FLOAT_TYPE_P(rettype) + && COMPLEX_FLOAT_TYPE_P(TREE_TYPE(args[0]))))) + { + excess_type = excess_precision_type(TREE_TYPE(args[0])); + if (excess_type != NULL_TREE) + { + tree excess_fndecl = mathfn_built_in(excess_type, + DECL_FUNCTION_CODE(fndecl)); + if (excess_fndecl == NULL_TREE) + excess_type = NULL_TREE; + else + { + fn = build_fold_addr_expr_loc(location, excess_fndecl); + for (int i = 0; i < nargs; ++i) + args[i] = ::convert(excess_type, args[i]); + } + } + } + + tree ret = build_call_array(excess_type != NULL_TREE ? excess_type : rettype, + fn, nargs, args); + delete[] args; + + SET_EXPR_LOCATION(ret, location); + + if (has_closure) + { + tree closure_tree = func->closure()->get_tree(context); + if (closure_tree != error_mark_node) + CALL_EXPR_STATIC_CHAIN(ret) = closure_tree; + } + + // If this is a recursive function type which returns itself, as in + // type F func() F + // we have used ptr_type_node for the return type. Add a cast here + // to the correct type. + if (TREE_TYPE(ret) == ptr_type_node) + { + tree t = this->type()->base()->get_tree(gogo); + ret = fold_convert_loc(location, t, ret); + } + + if (excess_type != NULL_TREE) + { + // Calling convert here can undo our excess precision change. + // That may or may not be a bug in convert_to_real. + ret = build1(NOP_EXPR, rettype, ret); + } + + // If there is more than one result, we will refer to the call + // multiple times. + if (fntype->results() != NULL && fntype->results()->size() > 1) + ret = save_expr(ret); + + this->tree_ = ret; + + return ret; +} + +// Make a call expression. + +Call_expression* +Expression::make_call(Expression* fn, Expression_list* args, bool is_varargs, + source_location location) +{ + return new Call_expression(fn, args, is_varargs, location); +} + +// A single result from a call which returns multiple results. + +class Call_result_expression : public Expression +{ + public: + Call_result_expression(Call_expression* call, unsigned int index) + : Expression(EXPRESSION_CALL_RESULT, call->location()), + call_(call), index_(index) + { } + + protected: + int + do_traverse(Traverse*); + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return new Call_result_expression(this->call_->call_expression(), + this->index_); + } + + bool + do_must_eval_in_order() const + { return true; } + + tree + do_get_tree(Translate_context*); + + private: + // The underlying call expression. + Expression* call_; + // Which result we want. + unsigned int index_; +}; + +// Traverse a call result. + +int +Call_result_expression::do_traverse(Traverse* traverse) +{ + if (traverse->remember_expression(this->call_)) + { + // We have already traversed the call expression. + return TRAVERSE_CONTINUE; + } + return Expression::traverse(&this->call_, traverse); +} + +// Get the type. + +Type* +Call_result_expression::do_type() +{ + if (this->classification() == EXPRESSION_ERROR) + return Type::make_error_type(); + + // THIS->CALL_ can be replaced with a temporary reference due to + // Call_expression::do_must_eval_in_order when there is an error. + Call_expression* ce = this->call_->call_expression(); + if (ce == NULL) + { + this->set_is_error(); + return Type::make_error_type(); + } + Function_type* fntype = ce->get_function_type(); + if (fntype == NULL) + { + this->set_is_error(); + return Type::make_error_type(); + } + const Typed_identifier_list* results = fntype->results(); + if (results == NULL) + { + this->report_error(_("number of results does not match " + "number of values")); + return Type::make_error_type(); + } + Typed_identifier_list::const_iterator pr = results->begin(); + for (unsigned int i = 0; i < this->index_; ++i) + { + if (pr == results->end()) + break; + ++pr; + } + if (pr == results->end()) + { + this->report_error(_("number of results does not match " + "number of values")); + return Type::make_error_type(); + } + return pr->type(); +} + +// Check the type. Just make sure that we trigger the warning in +// do_type. + +void +Call_result_expression::do_check_types(Gogo*) +{ + this->type(); +} + +// Determine the type. We have nothing to do here, but the 0 result +// needs to pass down to the caller. + +void +Call_result_expression::do_determine_type(const Type_context*) +{ + this->call_->determine_type_no_context(); +} + +// Return the tree. + +tree +Call_result_expression::do_get_tree(Translate_context* context) +{ + tree call_tree = this->call_->get_tree(context); + if (call_tree == error_mark_node) + return error_mark_node; + if (TREE_CODE(TREE_TYPE(call_tree)) != RECORD_TYPE) + { + gcc_assert(saw_errors()); + return error_mark_node; + } + tree field = TYPE_FIELDS(TREE_TYPE(call_tree)); + for (unsigned int i = 0; i < this->index_; ++i) + { + gcc_assert(field != NULL_TREE); + field = DECL_CHAIN(field); + } + gcc_assert(field != NULL_TREE); + return build3(COMPONENT_REF, TREE_TYPE(field), call_tree, field, NULL_TREE); +} + +// Make a reference to a single result of a call which returns +// multiple results. + +Expression* +Expression::make_call_result(Call_expression* call, unsigned int index) +{ + return new Call_result_expression(call, index); +} + +// Class Index_expression. + +// Traversal. + +int +Index_expression::do_traverse(Traverse* traverse) +{ + if (Expression::traverse(&this->left_, traverse) == TRAVERSE_EXIT + || Expression::traverse(&this->start_, traverse) == TRAVERSE_EXIT + || (this->end_ != NULL + && Expression::traverse(&this->end_, traverse) == TRAVERSE_EXIT)) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Lower an index expression. This converts the generic index +// expression into an array index, a string index, or a map index. + +Expression* +Index_expression::do_lower(Gogo*, Named_object*, int) +{ + source_location location = this->location(); + Expression* left = this->left_; + Expression* start = this->start_; + Expression* end = this->end_; + + Type* type = left->type(); + if (type->is_error_type()) + return Expression::make_error(location); + else if (left->is_type_expression()) + { + error_at(location, "attempt to index type expression"); + return Expression::make_error(location); + } + else if (type->array_type() != NULL) + return Expression::make_array_index(left, start, end, location); + else if (type->points_to() != NULL + && type->points_to()->array_type() != NULL + && !type->points_to()->is_open_array_type()) + { + Expression* deref = Expression::make_unary(OPERATOR_MULT, left, + location); + return Expression::make_array_index(deref, start, end, location); + } + else if (type->is_string_type()) + return Expression::make_string_index(left, start, end, location); + else if (type->map_type() != NULL) + { + if (end != NULL) + { + error_at(location, "invalid slice of map"); + return Expression::make_error(location); + } + Map_index_expression* ret= Expression::make_map_index(left, start, + location); + if (this->is_lvalue_) + ret->set_is_lvalue(); + return ret; + } + else + { + error_at(location, + "attempt to index object which is not array, string, or map"); + return Expression::make_error(location); + } +} + +// Make an index expression. + +Expression* +Expression::make_index(Expression* left, Expression* start, Expression* end, + source_location location) +{ + return new Index_expression(left, start, end, location); +} + +// An array index. This is used for both indexing and slicing. + +class Array_index_expression : public Expression +{ + public: + Array_index_expression(Expression* array, Expression* start, + Expression* end, source_location location) + : Expression(EXPRESSION_ARRAY_INDEX, location), + array_(array), start_(start), end_(end), type_(NULL) + { } + + protected: + int + do_traverse(Traverse*); + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return Expression::make_array_index(this->array_->copy(), + this->start_->copy(), + (this->end_ == NULL + ? NULL + : this->end_->copy()), + this->location()); + } + + bool + do_is_addressable() const; + + void + do_address_taken(bool escapes) + { this->array_->address_taken(escapes); } + + tree + do_get_tree(Translate_context*); + + private: + // The array we are getting a value from. + Expression* array_; + // The start or only index. + Expression* start_; + // The end index of a slice. This may be NULL for a simple array + // index, or it may be a nil expression for the length of the array. + Expression* end_; + // The type of the expression. + Type* type_; +}; + +// Array index traversal. + +int +Array_index_expression::do_traverse(Traverse* traverse) +{ + if (Expression::traverse(&this->array_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (Expression::traverse(&this->start_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (this->end_ != NULL) + { + if (Expression::traverse(&this->end_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +// Return the type of an array index. + +Type* +Array_index_expression::do_type() +{ + if (this->type_ == NULL) + { + Array_type* type = this->array_->type()->array_type(); + if (type == NULL) + this->type_ = Type::make_error_type(); + else if (this->end_ == NULL) + this->type_ = type->element_type(); + else if (type->is_open_array_type()) + { + // A slice of a slice has the same type as the original + // slice. + this->type_ = this->array_->type()->deref(); + } + else + { + // A slice of an array is a slice. + this->type_ = Type::make_array_type(type->element_type(), NULL); + } + } + return this->type_; +} + +// Set the type of an array index. + +void +Array_index_expression::do_determine_type(const Type_context*) +{ + this->array_->determine_type_no_context(); + this->start_->determine_type_no_context(); + if (this->end_ != NULL) + this->end_->determine_type_no_context(); +} + +// Check types of an array index. + +void +Array_index_expression::do_check_types(Gogo*) +{ + if (this->start_->type()->integer_type() == NULL) + this->report_error(_("index must be integer")); + if (this->end_ != NULL + && this->end_->type()->integer_type() == NULL + && !this->end_->is_nil_expression()) + this->report_error(_("slice end must be integer")); + + Array_type* array_type = this->array_->type()->array_type(); + if (array_type == NULL) + { + gcc_assert(this->array_->type()->is_error_type()); + return; + } + + unsigned int int_bits = + Type::lookup_integer_type("int")->integer_type()->bits(); + + Type* dummy; + mpz_t lval; + mpz_init(lval); + bool lval_valid = (array_type->length() != NULL + && array_type->length()->integer_constant_value(true, + lval, + &dummy)); + mpz_t ival; + mpz_init(ival); + if (this->start_->integer_constant_value(true, ival, &dummy)) + { + if (mpz_sgn(ival) < 0 + || mpz_sizeinbase(ival, 2) >= int_bits + || (lval_valid + && (this->end_ == NULL + ? mpz_cmp(ival, lval) >= 0 + : mpz_cmp(ival, lval) > 0))) + { + error_at(this->start_->location(), "array index out of bounds"); + this->set_is_error(); + } + } + if (this->end_ != NULL && !this->end_->is_nil_expression()) + { + if (this->end_->integer_constant_value(true, ival, &dummy)) + { + if (mpz_sgn(ival) < 0 + || mpz_sizeinbase(ival, 2) >= int_bits + || (lval_valid && mpz_cmp(ival, lval) > 0)) + { + error_at(this->end_->location(), "array index out of bounds"); + this->set_is_error(); + } + } + } + mpz_clear(ival); + mpz_clear(lval); + + // A slice of an array requires an addressable array. A slice of a + // slice is always possible. + if (this->end_ != NULL + && !array_type->is_open_array_type() + && !this->array_->is_addressable()) + this->report_error(_("array is not addressable")); +} + +// Return whether this expression is addressable. + +bool +Array_index_expression::do_is_addressable() const +{ + // A slice expression is not addressable. + if (this->end_ != NULL) + return false; + + // An index into a slice is addressable. + if (this->array_->type()->is_open_array_type()) + return true; + + // An index into an array is addressable if the array is + // addressable. + return this->array_->is_addressable(); +} + +// Get a tree for an array index. + +tree +Array_index_expression::do_get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + source_location loc = this->location(); + + Array_type* array_type = this->array_->type()->array_type(); + if (array_type == NULL) + { + gcc_assert(this->array_->type()->is_error_type()); + return error_mark_node; + } + + tree type_tree = array_type->get_tree(gogo); + if (type_tree == error_mark_node) + return error_mark_node; + + tree array_tree = this->array_->get_tree(context); + if (array_tree == error_mark_node) + return error_mark_node; + + if (array_type->length() == NULL && !DECL_P(array_tree)) + array_tree = save_expr(array_tree); + tree length_tree = array_type->length_tree(gogo, array_tree); + if (length_tree == error_mark_node) + return error_mark_node; + length_tree = save_expr(length_tree); + tree length_type = TREE_TYPE(length_tree); + + tree bad_index = boolean_false_node; + + tree start_tree = this->start_->get_tree(context); + if (start_tree == error_mark_node) + return error_mark_node; + if (!DECL_P(start_tree)) + start_tree = save_expr(start_tree); + if (!INTEGRAL_TYPE_P(TREE_TYPE(start_tree))) + start_tree = convert_to_integer(length_type, start_tree); + + bad_index = Expression::check_bounds(start_tree, length_type, bad_index, + loc); + + start_tree = fold_convert_loc(loc, length_type, start_tree); + bad_index = fold_build2_loc(loc, TRUTH_OR_EXPR, boolean_type_node, bad_index, + fold_build2_loc(loc, + (this->end_ == NULL + ? GE_EXPR + : GT_EXPR), + boolean_type_node, start_tree, + length_tree)); + + int code = (array_type->length() != NULL + ? (this->end_ == NULL + ? RUNTIME_ERROR_ARRAY_INDEX_OUT_OF_BOUNDS + : RUNTIME_ERROR_ARRAY_SLICE_OUT_OF_BOUNDS) + : (this->end_ == NULL + ? RUNTIME_ERROR_SLICE_INDEX_OUT_OF_BOUNDS + : RUNTIME_ERROR_SLICE_SLICE_OUT_OF_BOUNDS)); + tree crash = Gogo::runtime_error(code, loc); + + if (this->end_ == NULL) + { + // Simple array indexing. This has to return an l-value, so + // wrap the index check into START_TREE. + start_tree = build2(COMPOUND_EXPR, TREE_TYPE(start_tree), + build3(COND_EXPR, void_type_node, + bad_index, crash, NULL_TREE), + start_tree); + start_tree = fold_convert_loc(loc, sizetype, start_tree); + + if (array_type->length() != NULL) + { + // Fixed array. + return build4(ARRAY_REF, TREE_TYPE(type_tree), array_tree, + start_tree, NULL_TREE, NULL_TREE); + } + else + { + // Open array. + tree values = array_type->value_pointer_tree(gogo, array_tree); + tree element_type_tree = array_type->element_type()->get_tree(gogo); + if (element_type_tree == error_mark_node) + return error_mark_node; + tree element_size = TYPE_SIZE_UNIT(element_type_tree); + tree offset = fold_build2_loc(loc, MULT_EXPR, sizetype, + start_tree, element_size); + tree ptr = fold_build2_loc(loc, POINTER_PLUS_EXPR, + TREE_TYPE(values), values, offset); + return build_fold_indirect_ref(ptr); + } + } + + // Array slice. + + tree capacity_tree = array_type->capacity_tree(gogo, array_tree); + if (capacity_tree == error_mark_node) + return error_mark_node; + capacity_tree = fold_convert_loc(loc, length_type, capacity_tree); + + tree end_tree; + if (this->end_->is_nil_expression()) + end_tree = length_tree; + else + { + end_tree = this->end_->get_tree(context); + if (end_tree == error_mark_node) + return error_mark_node; + if (!DECL_P(end_tree)) + end_tree = save_expr(end_tree); + if (!INTEGRAL_TYPE_P(TREE_TYPE(end_tree))) + end_tree = convert_to_integer(length_type, end_tree); + + bad_index = Expression::check_bounds(end_tree, length_type, bad_index, + loc); + + end_tree = fold_convert_loc(loc, length_type, end_tree); + + capacity_tree = save_expr(capacity_tree); + tree bad_end = fold_build2_loc(loc, TRUTH_OR_EXPR, boolean_type_node, + fold_build2_loc(loc, LT_EXPR, + boolean_type_node, + end_tree, start_tree), + fold_build2_loc(loc, GT_EXPR, + boolean_type_node, + end_tree, capacity_tree)); + bad_index = fold_build2_loc(loc, TRUTH_OR_EXPR, boolean_type_node, + bad_index, bad_end); + } + + tree element_type_tree = array_type->element_type()->get_tree(gogo); + if (element_type_tree == error_mark_node) + return error_mark_node; + tree element_size = TYPE_SIZE_UNIT(element_type_tree); + + tree offset = fold_build2_loc(loc, MULT_EXPR, sizetype, + fold_convert_loc(loc, sizetype, start_tree), + element_size); + + tree value_pointer = array_type->value_pointer_tree(gogo, array_tree); + if (value_pointer == error_mark_node) + return error_mark_node; + + value_pointer = fold_build2_loc(loc, POINTER_PLUS_EXPR, + TREE_TYPE(value_pointer), + value_pointer, offset); + + tree result_length_tree = fold_build2_loc(loc, MINUS_EXPR, length_type, + end_tree, start_tree); + + tree result_capacity_tree = fold_build2_loc(loc, MINUS_EXPR, length_type, + capacity_tree, start_tree); + + tree struct_tree = this->type()->get_tree(gogo); + gcc_assert(TREE_CODE(struct_tree) == RECORD_TYPE); + + VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 3); + + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + tree field = TYPE_FIELDS(struct_tree); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__values") == 0); + elt->index = field; + elt->value = value_pointer; + + elt = VEC_quick_push(constructor_elt, init, NULL); + field = DECL_CHAIN(field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__count") == 0); + elt->index = field; + elt->value = fold_convert_loc(loc, TREE_TYPE(field), result_length_tree); + + elt = VEC_quick_push(constructor_elt, init, NULL); + field = DECL_CHAIN(field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__capacity") == 0); + elt->index = field; + elt->value = fold_convert_loc(loc, TREE_TYPE(field), result_capacity_tree); + + tree constructor = build_constructor(struct_tree, init); + + if (TREE_CONSTANT(value_pointer) + && TREE_CONSTANT(result_length_tree) + && TREE_CONSTANT(result_capacity_tree)) + TREE_CONSTANT(constructor) = 1; + + return fold_build2_loc(loc, COMPOUND_EXPR, TREE_TYPE(constructor), + build3(COND_EXPR, void_type_node, + bad_index, crash, NULL_TREE), + constructor); +} + +// Make an array index expression. END may be NULL. + +Expression* +Expression::make_array_index(Expression* array, Expression* start, + Expression* end, source_location location) +{ + // Taking a slice of a composite literal requires moving the literal + // onto the heap. + if (end != NULL && array->is_composite_literal()) + { + array = Expression::make_heap_composite(array, location); + array = Expression::make_unary(OPERATOR_MULT, array, location); + } + return new Array_index_expression(array, start, end, location); +} + +// A string index. This is used for both indexing and slicing. + +class String_index_expression : public Expression +{ + public: + String_index_expression(Expression* string, Expression* start, + Expression* end, source_location location) + : Expression(EXPRESSION_STRING_INDEX, location), + string_(string), start_(start), end_(end) + { } + + protected: + int + do_traverse(Traverse*); + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return Expression::make_string_index(this->string_->copy(), + this->start_->copy(), + (this->end_ == NULL + ? NULL + : this->end_->copy()), + this->location()); + } + + tree + do_get_tree(Translate_context*); + + private: + // The string we are getting a value from. + Expression* string_; + // The start or only index. + Expression* start_; + // The end index of a slice. This may be NULL for a single index, + // or it may be a nil expression for the length of the string. + Expression* end_; +}; + +// String index traversal. + +int +String_index_expression::do_traverse(Traverse* traverse) +{ + if (Expression::traverse(&this->string_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (Expression::traverse(&this->start_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (this->end_ != NULL) + { + if (Expression::traverse(&this->end_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +// Return the type of a string index. + +Type* +String_index_expression::do_type() +{ + if (this->end_ == NULL) + return Type::lookup_integer_type("uint8"); + else + return this->string_->type(); +} + +// Determine the type of a string index. + +void +String_index_expression::do_determine_type(const Type_context*) +{ + this->string_->determine_type_no_context(); + this->start_->determine_type_no_context(); + if (this->end_ != NULL) + this->end_->determine_type_no_context(); +} + +// Check types of a string index. + +void +String_index_expression::do_check_types(Gogo*) +{ + if (this->start_->type()->integer_type() == NULL) + this->report_error(_("index must be integer")); + if (this->end_ != NULL + && this->end_->type()->integer_type() == NULL + && !this->end_->is_nil_expression()) + this->report_error(_("slice end must be integer")); + + std::string sval; + bool sval_valid = this->string_->string_constant_value(&sval); + + mpz_t ival; + mpz_init(ival); + Type* dummy; + if (this->start_->integer_constant_value(true, ival, &dummy)) + { + if (mpz_sgn(ival) < 0 + || (sval_valid && mpz_cmp_ui(ival, sval.length()) >= 0)) + { + error_at(this->start_->location(), "string index out of bounds"); + this->set_is_error(); + } + } + if (this->end_ != NULL && !this->end_->is_nil_expression()) + { + if (this->end_->integer_constant_value(true, ival, &dummy)) + { + if (mpz_sgn(ival) < 0 + || (sval_valid && mpz_cmp_ui(ival, sval.length()) > 0)) + { + error_at(this->end_->location(), "string index out of bounds"); + this->set_is_error(); + } + } + } + mpz_clear(ival); +} + +// Get a tree for a string index. + +tree +String_index_expression::do_get_tree(Translate_context* context) +{ + source_location loc = this->location(); + + tree string_tree = this->string_->get_tree(context); + if (string_tree == error_mark_node) + return error_mark_node; + + if (this->string_->type()->points_to() != NULL) + string_tree = build_fold_indirect_ref(string_tree); + if (!DECL_P(string_tree)) + string_tree = save_expr(string_tree); + tree string_type = TREE_TYPE(string_tree); + + tree length_tree = String_type::length_tree(context->gogo(), string_tree); + length_tree = save_expr(length_tree); + tree length_type = TREE_TYPE(length_tree); + + tree bad_index = boolean_false_node; + + tree start_tree = this->start_->get_tree(context); + if (start_tree == error_mark_node) + return error_mark_node; + if (!DECL_P(start_tree)) + start_tree = save_expr(start_tree); + if (!INTEGRAL_TYPE_P(TREE_TYPE(start_tree))) + start_tree = convert_to_integer(length_type, start_tree); + + bad_index = Expression::check_bounds(start_tree, length_type, bad_index, + loc); + + start_tree = fold_convert_loc(loc, length_type, start_tree); + + int code = (this->end_ == NULL + ? RUNTIME_ERROR_STRING_INDEX_OUT_OF_BOUNDS + : RUNTIME_ERROR_STRING_SLICE_OUT_OF_BOUNDS); + tree crash = Gogo::runtime_error(code, loc); + + if (this->end_ == NULL) + { + bad_index = fold_build2_loc(loc, TRUTH_OR_EXPR, boolean_type_node, + bad_index, + fold_build2_loc(loc, GE_EXPR, + boolean_type_node, + start_tree, length_tree)); + + tree bytes_tree = String_type::bytes_tree(context->gogo(), string_tree); + tree ptr = fold_build2_loc(loc, POINTER_PLUS_EXPR, TREE_TYPE(bytes_tree), + bytes_tree, + fold_convert_loc(loc, sizetype, start_tree)); + tree index = build_fold_indirect_ref_loc(loc, ptr); + + return build2(COMPOUND_EXPR, TREE_TYPE(index), + build3(COND_EXPR, void_type_node, + bad_index, crash, NULL_TREE), + index); + } + else + { + tree end_tree; + if (this->end_->is_nil_expression()) + end_tree = build_int_cst(length_type, -1); + else + { + end_tree = this->end_->get_tree(context); + if (end_tree == error_mark_node) + return error_mark_node; + if (!DECL_P(end_tree)) + end_tree = save_expr(end_tree); + if (!INTEGRAL_TYPE_P(TREE_TYPE(end_tree))) + end_tree = convert_to_integer(length_type, end_tree); + + bad_index = Expression::check_bounds(end_tree, length_type, + bad_index, loc); + + end_tree = fold_convert_loc(loc, length_type, end_tree); + } + + static tree strslice_fndecl; + tree ret = Gogo::call_builtin(&strslice_fndecl, + loc, + "__go_string_slice", + 3, + string_type, + string_type, + string_tree, + length_type, + start_tree, + length_type, + end_tree); + if (ret == error_mark_node) + return error_mark_node; + // This will panic if the bounds are out of range for the + // string. + TREE_NOTHROW(strslice_fndecl) = 0; + + if (bad_index == boolean_false_node) + return ret; + else + return build2(COMPOUND_EXPR, TREE_TYPE(ret), + build3(COND_EXPR, void_type_node, + bad_index, crash, NULL_TREE), + ret); + } +} + +// Make a string index expression. END may be NULL. + +Expression* +Expression::make_string_index(Expression* string, Expression* start, + Expression* end, source_location location) +{ + return new String_index_expression(string, start, end, location); +} + +// Class Map_index. + +// Get the type of the map. + +Map_type* +Map_index_expression::get_map_type() const +{ + Map_type* mt = this->map_->type()->deref()->map_type(); + if (mt == NULL) + gcc_assert(saw_errors()); + return mt; +} + +// Map index traversal. + +int +Map_index_expression::do_traverse(Traverse* traverse) +{ + if (Expression::traverse(&this->map_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return Expression::traverse(&this->index_, traverse); +} + +// Return the type of a map index. + +Type* +Map_index_expression::do_type() +{ + Map_type* mt = this->get_map_type(); + if (mt == NULL) + return Type::make_error_type(); + Type* type = mt->val_type(); + // If this map index is in a tuple assignment, we actually return a + // pointer to the value type. Tuple_map_assignment_statement is + // responsible for handling this correctly. We need to get the type + // right in case this gets assigned to a temporary variable. + if (this->is_in_tuple_assignment_) + type = Type::make_pointer_type(type); + return type; +} + +// Fix the type of a map index. + +void +Map_index_expression::do_determine_type(const Type_context*) +{ + this->map_->determine_type_no_context(); + Map_type* mt = this->get_map_type(); + Type* key_type = mt == NULL ? NULL : mt->key_type(); + Type_context subcontext(key_type, false); + this->index_->determine_type(&subcontext); +} + +// Check types of a map index. + +void +Map_index_expression::do_check_types(Gogo*) +{ + std::string reason; + Map_type* mt = this->get_map_type(); + if (mt == NULL) + return; + if (!Type::are_assignable(mt->key_type(), this->index_->type(), &reason)) + { + if (reason.empty()) + this->report_error(_("incompatible type for map index")); + else + { + error_at(this->location(), "incompatible type for map index (%s)", + reason.c_str()); + this->set_is_error(); + } + } +} + +// Get a tree for a map index. + +tree +Map_index_expression::do_get_tree(Translate_context* context) +{ + Map_type* type = this->get_map_type(); + if (type == NULL) + return error_mark_node; + + tree valptr = this->get_value_pointer(context, this->is_lvalue_); + if (valptr == error_mark_node) + return error_mark_node; + valptr = save_expr(valptr); + + tree val_type_tree = TREE_TYPE(TREE_TYPE(valptr)); + + if (this->is_lvalue_) + return build_fold_indirect_ref(valptr); + else if (this->is_in_tuple_assignment_) + { + // Tuple_map_assignment_statement is responsible for using this + // appropriately. + return valptr; + } + else + { + return fold_build3(COND_EXPR, val_type_tree, + fold_build2(EQ_EXPR, boolean_type_node, valptr, + fold_convert(TREE_TYPE(valptr), + null_pointer_node)), + type->val_type()->get_init_tree(context->gogo(), + false), + build_fold_indirect_ref(valptr)); + } +} + +// Get a tree for the map index. This returns a tree which evaluates +// to a pointer to a value. The pointer will be NULL if the key is +// not in the map. + +tree +Map_index_expression::get_value_pointer(Translate_context* context, + bool insert) +{ + Map_type* type = this->get_map_type(); + if (type == NULL) + return error_mark_node; + + tree map_tree = this->map_->get_tree(context); + tree index_tree = this->index_->get_tree(context); + index_tree = Expression::convert_for_assignment(context, type->key_type(), + this->index_->type(), + index_tree, + this->location()); + if (map_tree == error_mark_node || index_tree == error_mark_node) + return error_mark_node; + + if (this->map_->type()->points_to() != NULL) + map_tree = build_fold_indirect_ref(map_tree); + + // We need to pass in a pointer to the key, so stuff it into a + // variable. + tree tmp; + tree make_tmp; + if (current_function_decl != NULL) + { + tmp = create_tmp_var(TREE_TYPE(index_tree), get_name(index_tree)); + DECL_IGNORED_P(tmp) = 0; + DECL_INITIAL(tmp) = index_tree; + make_tmp = build1(DECL_EXPR, void_type_node, tmp); + TREE_ADDRESSABLE(tmp) = 1; + } + else + { + tmp = build_decl(this->location(), VAR_DECL, create_tmp_var_name("M"), + TREE_TYPE(index_tree)); + DECL_EXTERNAL(tmp) = 0; + TREE_PUBLIC(tmp) = 0; + TREE_STATIC(tmp) = 1; + DECL_ARTIFICIAL(tmp) = 1; + if (!TREE_CONSTANT(index_tree)) + make_tmp = fold_build2_loc(this->location(), INIT_EXPR, void_type_node, + tmp, index_tree); + else + { + TREE_READONLY(tmp) = 1; + TREE_CONSTANT(tmp) = 1; + DECL_INITIAL(tmp) = index_tree; + make_tmp = NULL_TREE; + } + rest_of_decl_compilation(tmp, 1, 0); + } + tree tmpref = fold_convert_loc(this->location(), const_ptr_type_node, + build_fold_addr_expr_loc(this->location(), + tmp)); + + static tree map_index_fndecl; + tree call = Gogo::call_builtin(&map_index_fndecl, + this->location(), + "__go_map_index", + 3, + const_ptr_type_node, + TREE_TYPE(map_tree), + map_tree, + const_ptr_type_node, + tmpref, + boolean_type_node, + (insert + ? boolean_true_node + : boolean_false_node)); + if (call == error_mark_node) + return error_mark_node; + // This can panic on a map of interface type if the interface holds + // an uncomparable or unhashable type. + TREE_NOTHROW(map_index_fndecl) = 0; + + tree val_type_tree = type->val_type()->get_tree(context->gogo()); + if (val_type_tree == error_mark_node) + return error_mark_node; + tree ptr_val_type_tree = build_pointer_type(val_type_tree); + + tree ret = fold_convert_loc(this->location(), ptr_val_type_tree, call); + if (make_tmp != NULL_TREE) + ret = build2(COMPOUND_EXPR, ptr_val_type_tree, make_tmp, ret); + return ret; +} + +// Make a map index expression. + +Map_index_expression* +Expression::make_map_index(Expression* map, Expression* index, + source_location location) +{ + return new Map_index_expression(map, index, location); +} + +// Class Field_reference_expression. + +// Return the type of a field reference. + +Type* +Field_reference_expression::do_type() +{ + Type* type = this->expr_->type(); + if (type->is_error_type()) + return type; + Struct_type* struct_type = type->struct_type(); + gcc_assert(struct_type != NULL); + return struct_type->field(this->field_index_)->type(); +} + +// Check the types for a field reference. + +void +Field_reference_expression::do_check_types(Gogo*) +{ + Type* type = this->expr_->type(); + if (type->is_error_type()) + return; + Struct_type* struct_type = type->struct_type(); + gcc_assert(struct_type != NULL); + gcc_assert(struct_type->field(this->field_index_) != NULL); +} + +// Get a tree for a field reference. + +tree +Field_reference_expression::do_get_tree(Translate_context* context) +{ + tree struct_tree = this->expr_->get_tree(context); + if (struct_tree == error_mark_node + || TREE_TYPE(struct_tree) == error_mark_node) + return error_mark_node; + gcc_assert(TREE_CODE(TREE_TYPE(struct_tree)) == RECORD_TYPE); + tree field = TYPE_FIELDS(TREE_TYPE(struct_tree)); + if (field == NULL_TREE) + { + // This can happen for a type which refers to itself indirectly + // and then turns out to be erroneous. + gcc_assert(saw_errors()); + return error_mark_node; + } + for (unsigned int i = this->field_index_; i > 0; --i) + { + field = DECL_CHAIN(field); + gcc_assert(field != NULL_TREE); + } + if (TREE_TYPE(field) == error_mark_node) + return error_mark_node; + return build3(COMPONENT_REF, TREE_TYPE(field), struct_tree, field, + NULL_TREE); +} + +// Make a reference to a qualified identifier in an expression. + +Field_reference_expression* +Expression::make_field_reference(Expression* expr, unsigned int field_index, + source_location location) +{ + return new Field_reference_expression(expr, field_index, location); +} + +// Class Interface_field_reference_expression. + +// Return a tree for the pointer to the function to call. + +tree +Interface_field_reference_expression::get_function_tree(Translate_context*, + tree expr) +{ + if (this->expr_->type()->points_to() != NULL) + expr = build_fold_indirect_ref(expr); + + tree expr_type = TREE_TYPE(expr); + gcc_assert(TREE_CODE(expr_type) == RECORD_TYPE); + + tree field = TYPE_FIELDS(expr_type); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__methods") == 0); + + tree table = build3(COMPONENT_REF, TREE_TYPE(field), expr, field, NULL_TREE); + gcc_assert(POINTER_TYPE_P(TREE_TYPE(table))); + + table = build_fold_indirect_ref(table); + gcc_assert(TREE_CODE(TREE_TYPE(table)) == RECORD_TYPE); + + std::string name = Gogo::unpack_hidden_name(this->name_); + for (field = DECL_CHAIN(TYPE_FIELDS(TREE_TYPE(table))); + field != NULL_TREE; + field = DECL_CHAIN(field)) + { + if (name == IDENTIFIER_POINTER(DECL_NAME(field))) + break; + } + gcc_assert(field != NULL_TREE); + + return build3(COMPONENT_REF, TREE_TYPE(field), table, field, NULL_TREE); +} + +// Return a tree for the first argument to pass to the interface +// function. + +tree +Interface_field_reference_expression::get_underlying_object_tree( + Translate_context*, + tree expr) +{ + if (this->expr_->type()->points_to() != NULL) + expr = build_fold_indirect_ref(expr); + + tree expr_type = TREE_TYPE(expr); + gcc_assert(TREE_CODE(expr_type) == RECORD_TYPE); + + tree field = DECL_CHAIN(TYPE_FIELDS(expr_type)); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__object") == 0); + + return build3(COMPONENT_REF, TREE_TYPE(field), expr, field, NULL_TREE); +} + +// Traversal. + +int +Interface_field_reference_expression::do_traverse(Traverse* traverse) +{ + return Expression::traverse(&this->expr_, traverse); +} + +// Return the type of an interface field reference. + +Type* +Interface_field_reference_expression::do_type() +{ + Type* expr_type = this->expr_->type(); + + Type* points_to = expr_type->points_to(); + if (points_to != NULL) + expr_type = points_to; + + Interface_type* interface_type = expr_type->interface_type(); + if (interface_type == NULL) + return Type::make_error_type(); + + const Typed_identifier* method = interface_type->find_method(this->name_); + if (method == NULL) + return Type::make_error_type(); + + return method->type(); +} + +// Determine types. + +void +Interface_field_reference_expression::do_determine_type(const Type_context*) +{ + this->expr_->determine_type_no_context(); +} + +// Check the types for an interface field reference. + +void +Interface_field_reference_expression::do_check_types(Gogo*) +{ + Type* type = this->expr_->type(); + + Type* points_to = type->points_to(); + if (points_to != NULL) + type = points_to; + + Interface_type* interface_type = type->interface_type(); + if (interface_type == NULL) + this->report_error(_("expected interface or pointer to interface")); + else + { + const Typed_identifier* method = + interface_type->find_method(this->name_); + if (method == NULL) + { + error_at(this->location(), "method %qs not in interface", + Gogo::message_name(this->name_).c_str()); + this->set_is_error(); + } + } +} + +// Get a tree for a reference to a field in an interface. There is no +// standard tree type representation for this: it's a function +// attached to its first argument, like a Bound_method_expression. +// The only places it may currently be used are in a Call_expression +// or a Go_statement, which will take it apart directly. So this has +// nothing to do at present. + +tree +Interface_field_reference_expression::do_get_tree(Translate_context*) +{ + gcc_unreachable(); +} + +// Make a reference to a field in an interface. + +Expression* +Expression::make_interface_field_reference(Expression* expr, + const std::string& field, + source_location location) +{ + return new Interface_field_reference_expression(expr, field, location); +} + +// A general selector. This is a Parser_expression for LEFT.NAME. It +// is lowered after we know the type of the left hand side. + +class Selector_expression : public Parser_expression +{ + public: + Selector_expression(Expression* left, const std::string& name, + source_location location) + : Parser_expression(EXPRESSION_SELECTOR, location), + left_(left), name_(name) + { } + + protected: + int + do_traverse(Traverse* traverse) + { return Expression::traverse(&this->left_, traverse); } + + Expression* + do_lower(Gogo*, Named_object*, int); + + Expression* + do_copy() + { + return new Selector_expression(this->left_->copy(), this->name_, + this->location()); + } + + private: + Expression* + lower_method_expression(Gogo*); + + // The expression on the left hand side. + Expression* left_; + // The name on the right hand side. + std::string name_; +}; + +// Lower a selector expression once we know the real type of the left +// hand side. + +Expression* +Selector_expression::do_lower(Gogo* gogo, Named_object*, int) +{ + Expression* left = this->left_; + if (left->is_type_expression()) + return this->lower_method_expression(gogo); + return Type::bind_field_or_method(gogo, left->type(), left, this->name_, + this->location()); +} + +// Lower a method expression T.M or (*T).M. We turn this into a +// function literal. + +Expression* +Selector_expression::lower_method_expression(Gogo* gogo) +{ + source_location location = this->location(); + Type* type = this->left_->type(); + const std::string& name(this->name_); + + bool is_pointer; + if (type->points_to() == NULL) + is_pointer = false; + else + { + is_pointer = true; + type = type->points_to(); + } + Named_type* nt = type->named_type(); + if (nt == NULL) + { + error_at(location, + ("method expression requires named type or " + "pointer to named type")); + return Expression::make_error(location); + } + + bool is_ambiguous; + Method* method = nt->method_function(name, &is_ambiguous); + if (method == NULL) + { + if (!is_ambiguous) + error_at(location, "type %<%s%> has no method %<%s%>", + nt->message_name().c_str(), + Gogo::message_name(name).c_str()); + else + error_at(location, "method %<%s%> is ambiguous in type %<%s%>", + Gogo::message_name(name).c_str(), + nt->message_name().c_str()); + return Expression::make_error(location); + } + + if (!is_pointer && !method->is_value_method()) + { + error_at(location, "method requires pointer (use %<(*%s).%s)%>", + nt->message_name().c_str(), + Gogo::message_name(name).c_str()); + return Expression::make_error(location); + } + + // Build a new function type in which the receiver becomes the first + // argument. + Function_type* method_type = method->type(); + gcc_assert(method_type->is_method()); + + const char* const receiver_name = "$this"; + Typed_identifier_list* parameters = new Typed_identifier_list(); + parameters->push_back(Typed_identifier(receiver_name, this->left_->type(), + location)); + + const Typed_identifier_list* method_parameters = method_type->parameters(); + if (method_parameters != NULL) + { + for (Typed_identifier_list::const_iterator p = method_parameters->begin(); + p != method_parameters->end(); + ++p) + parameters->push_back(*p); + } + + const Typed_identifier_list* method_results = method_type->results(); + Typed_identifier_list* results; + if (method_results == NULL) + results = NULL; + else + { + results = new Typed_identifier_list(); + for (Typed_identifier_list::const_iterator p = method_results->begin(); + p != method_results->end(); + ++p) + results->push_back(*p); + } + + Function_type* fntype = Type::make_function_type(NULL, parameters, results, + location); + if (method_type->is_varargs()) + fntype->set_is_varargs(); + + // We generate methods which always takes a pointer to the receiver + // as their first argument. If this is for a pointer type, we can + // simply reuse the existing function. We use an internal hack to + // get the right type. + + if (is_pointer) + { + Named_object* mno = (method->needs_stub_method() + ? method->stub_object() + : method->named_object()); + Expression* f = Expression::make_func_reference(mno, NULL, location); + f = Expression::make_cast(fntype, f, location); + Type_conversion_expression* tce = + static_cast<Type_conversion_expression*>(f); + tce->set_may_convert_function_types(); + return f; + } + + Named_object* no = gogo->start_function(Gogo::thunk_name(), fntype, false, + location); + + Named_object* vno = gogo->lookup(receiver_name, NULL); + gcc_assert(vno != NULL); + Expression* ve = Expression::make_var_reference(vno, location); + Expression* bm = Type::bind_field_or_method(gogo, nt, ve, name, location); + + // Even though we found the method above, if it has an error type we + // may see an error here. + if (bm->is_error_expression()) + { + gogo->finish_function(location); + return bm; + } + + Expression_list* args; + if (method_parameters == NULL) + args = NULL; + else + { + args = new Expression_list(); + for (Typed_identifier_list::const_iterator p = method_parameters->begin(); + p != method_parameters->end(); + ++p) + { + vno = gogo->lookup(p->name(), NULL); + gcc_assert(vno != NULL); + args->push_back(Expression::make_var_reference(vno, location)); + } + } + + Call_expression* call = Expression::make_call(bm, args, + method_type->is_varargs(), + location); + + size_t count = call->result_count(); + Statement* s; + if (count == 0) + s = Statement::make_statement(call); + else + { + Expression_list* retvals = new Expression_list(); + if (count <= 1) + retvals->push_back(call); + else + { + for (size_t i = 0; i < count; ++i) + retvals->push_back(Expression::make_call_result(call, i)); + } + s = Statement::make_return_statement(no->func_value()->type()->results(), + retvals, location); + } + gogo->add_statement(s); + + gogo->finish_function(location); + + return Expression::make_func_reference(no, NULL, location); +} + +// Make a selector expression. + +Expression* +Expression::make_selector(Expression* left, const std::string& name, + source_location location) +{ + return new Selector_expression(left, name, location); +} + +// Implement the builtin function new. + +class Allocation_expression : public Expression +{ + public: + Allocation_expression(Type* type, source_location location) + : Expression(EXPRESSION_ALLOCATION, location), + type_(type) + { } + + protected: + int + do_traverse(Traverse* traverse) + { return Type::traverse(this->type_, traverse); } + + Type* + do_type() + { return Type::make_pointer_type(this->type_); } + + void + do_determine_type(const Type_context*) + { } + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { return new Allocation_expression(this->type_, this->location()); } + + tree + do_get_tree(Translate_context*); + + private: + // The type we are allocating. + Type* type_; +}; + +// Check the type of an allocation expression. + +void +Allocation_expression::do_check_types(Gogo*) +{ + if (this->type_->function_type() != NULL) + this->report_error(_("invalid new of function type")); +} + +// Return a tree for an allocation expression. + +tree +Allocation_expression::do_get_tree(Translate_context* context) +{ + tree type_tree = this->type_->get_tree(context->gogo()); + if (type_tree == error_mark_node) + return error_mark_node; + tree size_tree = TYPE_SIZE_UNIT(type_tree); + tree space = context->gogo()->allocate_memory(this->type_, size_tree, + this->location()); + if (space == error_mark_node) + return error_mark_node; + return fold_convert(build_pointer_type(type_tree), space); +} + +// Make an allocation expression. + +Expression* +Expression::make_allocation(Type* type, source_location location) +{ + return new Allocation_expression(type, location); +} + +// Implement the builtin function make. + +class Make_expression : public Expression +{ + public: + Make_expression(Type* type, Expression_list* args, source_location location) + : Expression(EXPRESSION_MAKE, location), + type_(type), args_(args) + { } + + protected: + int + do_traverse(Traverse* traverse); + + Type* + do_type() + { return this->type_; } + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return new Make_expression(this->type_, this->args_->copy(), + this->location()); + } + + tree + do_get_tree(Translate_context*); + + private: + // The type we are making. + Type* type_; + // The arguments to pass to the make routine. + Expression_list* args_; +}; + +// Traversal. + +int +Make_expression::do_traverse(Traverse* traverse) +{ + if (this->args_ != NULL + && this->args_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (Type::traverse(this->type_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Set types of arguments. + +void +Make_expression::do_determine_type(const Type_context*) +{ + if (this->args_ != NULL) + { + Type_context context(Type::lookup_integer_type("int"), false); + for (Expression_list::const_iterator pe = this->args_->begin(); + pe != this->args_->end(); + ++pe) + (*pe)->determine_type(&context); + } +} + +// Check types for a make expression. + +void +Make_expression::do_check_types(Gogo*) +{ + if (this->type_->channel_type() == NULL + && this->type_->map_type() == NULL + && (this->type_->array_type() == NULL + || this->type_->array_type()->length() != NULL)) + this->report_error(_("invalid type for make function")); + else if (!this->type_->check_make_expression(this->args_, this->location())) + this->set_is_error(); +} + +// Return a tree for a make expression. + +tree +Make_expression::do_get_tree(Translate_context* context) +{ + return this->type_->make_expression_tree(context, this->args_, + this->location()); +} + +// Make a make expression. + +Expression* +Expression::make_make(Type* type, Expression_list* args, + source_location location) +{ + return new Make_expression(type, args, location); +} + +// Construct a struct. + +class Struct_construction_expression : public Expression +{ + public: + Struct_construction_expression(Type* type, Expression_list* vals, + source_location location) + : Expression(EXPRESSION_STRUCT_CONSTRUCTION, location), + type_(type), vals_(vals) + { } + + // Return whether this is a constant initializer. + bool + is_constant_struct() const; + + protected: + int + do_traverse(Traverse* traverse); + + Type* + do_type() + { return this->type_; } + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return new Struct_construction_expression(this->type_, this->vals_->copy(), + this->location()); + } + + bool + do_is_addressable() const + { return true; } + + tree + do_get_tree(Translate_context*); + + void + do_export(Export*) const; + + private: + // The type of the struct to construct. + Type* type_; + // The list of values, in order of the fields in the struct. A NULL + // entry means that the field should be zero-initialized. + Expression_list* vals_; +}; + +// Traversal. + +int +Struct_construction_expression::do_traverse(Traverse* traverse) +{ + if (this->vals_ != NULL + && this->vals_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (Type::traverse(this->type_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Return whether this is a constant initializer. + +bool +Struct_construction_expression::is_constant_struct() const +{ + if (this->vals_ == NULL) + return true; + for (Expression_list::const_iterator pv = this->vals_->begin(); + pv != this->vals_->end(); + ++pv) + { + if (*pv != NULL + && !(*pv)->is_constant() + && (!(*pv)->is_composite_literal() + || (*pv)->is_nonconstant_composite_literal())) + return false; + } + + const Struct_field_list* fields = this->type_->struct_type()->fields(); + for (Struct_field_list::const_iterator pf = fields->begin(); + pf != fields->end(); + ++pf) + { + // There are no constant constructors for interfaces. + if (pf->type()->interface_type() != NULL) + return false; + } + + return true; +} + +// Final type determination. + +void +Struct_construction_expression::do_determine_type(const Type_context*) +{ + if (this->vals_ == NULL) + return; + const Struct_field_list* fields = this->type_->struct_type()->fields(); + Expression_list::const_iterator pv = this->vals_->begin(); + for (Struct_field_list::const_iterator pf = fields->begin(); + pf != fields->end(); + ++pf, ++pv) + { + if (pv == this->vals_->end()) + return; + if (*pv != NULL) + { + Type_context subcontext(pf->type(), false); + (*pv)->determine_type(&subcontext); + } + } + // Extra values are an error we will report elsewhere; we still want + // to determine the type to avoid knockon errors. + for (; pv != this->vals_->end(); ++pv) + (*pv)->determine_type_no_context(); +} + +// Check types. + +void +Struct_construction_expression::do_check_types(Gogo*) +{ + if (this->vals_ == NULL) + return; + + Struct_type* st = this->type_->struct_type(); + if (this->vals_->size() > st->field_count()) + { + this->report_error(_("too many expressions for struct")); + return; + } + + const Struct_field_list* fields = st->fields(); + Expression_list::const_iterator pv = this->vals_->begin(); + int i = 0; + for (Struct_field_list::const_iterator pf = fields->begin(); + pf != fields->end(); + ++pf, ++pv, ++i) + { + if (pv == this->vals_->end()) + { + this->report_error(_("too few expressions for struct")); + break; + } + + if (*pv == NULL) + continue; + + std::string reason; + if (!Type::are_assignable(pf->type(), (*pv)->type(), &reason)) + { + if (reason.empty()) + error_at((*pv)->location(), + "incompatible type for field %d in struct construction", + i + 1); + else + error_at((*pv)->location(), + ("incompatible type for field %d in " + "struct construction (%s)"), + i + 1, reason.c_str()); + this->set_is_error(); + } + } + gcc_assert(pv == this->vals_->end()); +} + +// Return a tree for constructing a struct. + +tree +Struct_construction_expression::do_get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + + if (this->vals_ == NULL) + return this->type_->get_init_tree(gogo, false); + + tree type_tree = this->type_->get_tree(gogo); + if (type_tree == error_mark_node) + return error_mark_node; + gcc_assert(TREE_CODE(type_tree) == RECORD_TYPE); + + bool is_constant = true; + const Struct_field_list* fields = this->type_->struct_type()->fields(); + VEC(constructor_elt,gc)* elts = VEC_alloc(constructor_elt, gc, + fields->size()); + Struct_field_list::const_iterator pf = fields->begin(); + Expression_list::const_iterator pv = this->vals_->begin(); + for (tree field = TYPE_FIELDS(type_tree); + field != NULL_TREE; + field = DECL_CHAIN(field), ++pf) + { + gcc_assert(pf != fields->end()); + + tree val; + if (pv == this->vals_->end()) + val = pf->type()->get_init_tree(gogo, false); + else if (*pv == NULL) + { + val = pf->type()->get_init_tree(gogo, false); + ++pv; + } + else + { + val = Expression::convert_for_assignment(context, pf->type(), + (*pv)->type(), + (*pv)->get_tree(context), + this->location()); + ++pv; + } + + if (val == error_mark_node || TREE_TYPE(val) == error_mark_node) + return error_mark_node; + + constructor_elt* elt = VEC_quick_push(constructor_elt, elts, NULL); + elt->index = field; + elt->value = val; + if (!TREE_CONSTANT(val)) + is_constant = false; + } + gcc_assert(pf == fields->end()); + + tree ret = build_constructor(type_tree, elts); + if (is_constant) + TREE_CONSTANT(ret) = 1; + return ret; +} + +// Export a struct construction. + +void +Struct_construction_expression::do_export(Export* exp) const +{ + exp->write_c_string("convert("); + exp->write_type(this->type_); + for (Expression_list::const_iterator pv = this->vals_->begin(); + pv != this->vals_->end(); + ++pv) + { + exp->write_c_string(", "); + if (*pv != NULL) + (*pv)->export_expression(exp); + } + exp->write_c_string(")"); +} + +// Make a struct composite literal. This used by the thunk code. + +Expression* +Expression::make_struct_composite_literal(Type* type, Expression_list* vals, + source_location location) +{ + gcc_assert(type->struct_type() != NULL); + return new Struct_construction_expression(type, vals, location); +} + +// Construct an array. This class is not used directly; instead we +// use the child classes, Fixed_array_construction_expression and +// Open_array_construction_expression. + +class Array_construction_expression : public Expression +{ + protected: + Array_construction_expression(Expression_classification classification, + Type* type, Expression_list* vals, + source_location location) + : Expression(classification, location), + type_(type), vals_(vals) + { } + + public: + // Return whether this is a constant initializer. + bool + is_constant_array() const; + + // Return the number of elements. + size_t + element_count() const + { return this->vals_ == NULL ? 0 : this->vals_->size(); } + +protected: + int + do_traverse(Traverse* traverse); + + Type* + do_type() + { return this->type_; } + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + bool + do_is_addressable() const + { return true; } + + void + do_export(Export*) const; + + // The list of values. + Expression_list* + vals() + { return this->vals_; } + + // Get a constructor tree for the array values. + tree + get_constructor_tree(Translate_context* context, tree type_tree); + + private: + // The type of the array to construct. + Type* type_; + // The list of values. + Expression_list* vals_; +}; + +// Traversal. + +int +Array_construction_expression::do_traverse(Traverse* traverse) +{ + if (this->vals_ != NULL + && this->vals_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (Type::traverse(this->type_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Return whether this is a constant initializer. + +bool +Array_construction_expression::is_constant_array() const +{ + if (this->vals_ == NULL) + return true; + + // There are no constant constructors for interfaces. + if (this->type_->array_type()->element_type()->interface_type() != NULL) + return false; + + for (Expression_list::const_iterator pv = this->vals_->begin(); + pv != this->vals_->end(); + ++pv) + { + if (*pv != NULL + && !(*pv)->is_constant() + && (!(*pv)->is_composite_literal() + || (*pv)->is_nonconstant_composite_literal())) + return false; + } + return true; +} + +// Final type determination. + +void +Array_construction_expression::do_determine_type(const Type_context*) +{ + if (this->vals_ == NULL) + return; + Type_context subcontext(this->type_->array_type()->element_type(), false); + for (Expression_list::const_iterator pv = this->vals_->begin(); + pv != this->vals_->end(); + ++pv) + { + if (*pv != NULL) + (*pv)->determine_type(&subcontext); + } +} + +// Check types. + +void +Array_construction_expression::do_check_types(Gogo*) +{ + if (this->vals_ == NULL) + return; + + Array_type* at = this->type_->array_type(); + int i = 0; + Type* element_type = at->element_type(); + for (Expression_list::const_iterator pv = this->vals_->begin(); + pv != this->vals_->end(); + ++pv, ++i) + { + if (*pv != NULL + && !Type::are_assignable(element_type, (*pv)->type(), NULL)) + { + error_at((*pv)->location(), + "incompatible type for element %d in composite literal", + i + 1); + this->set_is_error(); + } + } + + Expression* length = at->length(); + if (length != NULL) + { + mpz_t val; + mpz_init(val); + Type* type; + if (at->length()->integer_constant_value(true, val, &type)) + { + if (this->vals_->size() > mpz_get_ui(val)) + this->report_error(_("too many elements in composite literal")); + } + mpz_clear(val); + } +} + +// Get a constructor tree for the array values. + +tree +Array_construction_expression::get_constructor_tree(Translate_context* context, + tree type_tree) +{ + VEC(constructor_elt,gc)* values = VEC_alloc(constructor_elt, gc, + (this->vals_ == NULL + ? 0 + : this->vals_->size())); + Type* element_type = this->type_->array_type()->element_type(); + bool is_constant = true; + if (this->vals_ != NULL) + { + size_t i = 0; + for (Expression_list::const_iterator pv = this->vals_->begin(); + pv != this->vals_->end(); + ++pv, ++i) + { + constructor_elt* elt = VEC_quick_push(constructor_elt, values, NULL); + elt->index = size_int(i); + if (*pv == NULL) + elt->value = element_type->get_init_tree(context->gogo(), false); + else + { + tree value_tree = (*pv)->get_tree(context); + elt->value = Expression::convert_for_assignment(context, + element_type, + (*pv)->type(), + value_tree, + this->location()); + } + if (elt->value == error_mark_node) + return error_mark_node; + if (!TREE_CONSTANT(elt->value)) + is_constant = false; + } + } + + tree ret = build_constructor(type_tree, values); + if (is_constant) + TREE_CONSTANT(ret) = 1; + return ret; +} + +// Export an array construction. + +void +Array_construction_expression::do_export(Export* exp) const +{ + exp->write_c_string("convert("); + exp->write_type(this->type_); + if (this->vals_ != NULL) + { + for (Expression_list::const_iterator pv = this->vals_->begin(); + pv != this->vals_->end(); + ++pv) + { + exp->write_c_string(", "); + if (*pv != NULL) + (*pv)->export_expression(exp); + } + } + exp->write_c_string(")"); +} + +// Construct a fixed array. + +class Fixed_array_construction_expression : + public Array_construction_expression +{ + public: + Fixed_array_construction_expression(Type* type, Expression_list* vals, + source_location location) + : Array_construction_expression(EXPRESSION_FIXED_ARRAY_CONSTRUCTION, + type, vals, location) + { + gcc_assert(type->array_type() != NULL + && type->array_type()->length() != NULL); + } + + protected: + Expression* + do_copy() + { + return new Fixed_array_construction_expression(this->type(), + (this->vals() == NULL + ? NULL + : this->vals()->copy()), + this->location()); + } + + tree + do_get_tree(Translate_context*); +}; + +// Return a tree for constructing a fixed array. + +tree +Fixed_array_construction_expression::do_get_tree(Translate_context* context) +{ + return this->get_constructor_tree(context, + this->type()->get_tree(context->gogo())); +} + +// Construct an open array. + +class Open_array_construction_expression : public Array_construction_expression +{ + public: + Open_array_construction_expression(Type* type, Expression_list* vals, + source_location location) + : Array_construction_expression(EXPRESSION_OPEN_ARRAY_CONSTRUCTION, + type, vals, location) + { + gcc_assert(type->array_type() != NULL + && type->array_type()->length() == NULL); + } + + protected: + // Note that taking the address of an open array literal is invalid. + + Expression* + do_copy() + { + return new Open_array_construction_expression(this->type(), + (this->vals() == NULL + ? NULL + : this->vals()->copy()), + this->location()); + } + + tree + do_get_tree(Translate_context*); +}; + +// Return a tree for constructing an open array. + +tree +Open_array_construction_expression::do_get_tree(Translate_context* context) +{ + Array_type* array_type = this->type()->array_type(); + if (array_type == NULL) + { + gcc_assert(this->type()->is_error_type()); + return error_mark_node; + } + + Type* element_type = array_type->element_type(); + tree element_type_tree = element_type->get_tree(context->gogo()); + if (element_type_tree == error_mark_node) + return error_mark_node; + + tree values; + tree length_tree; + if (this->vals() == NULL || this->vals()->empty()) + { + // We need to create a unique value. + tree max = size_int(0); + tree constructor_type = build_array_type(element_type_tree, + build_index_type(max)); + if (constructor_type == error_mark_node) + return error_mark_node; + VEC(constructor_elt,gc)* vec = VEC_alloc(constructor_elt, gc, 1); + constructor_elt* elt = VEC_quick_push(constructor_elt, vec, NULL); + elt->index = size_int(0); + elt->value = element_type->get_init_tree(context->gogo(), false); + values = build_constructor(constructor_type, vec); + if (TREE_CONSTANT(elt->value)) + TREE_CONSTANT(values) = 1; + length_tree = size_int(0); + } + else + { + tree max = size_int(this->vals()->size() - 1); + tree constructor_type = build_array_type(element_type_tree, + build_index_type(max)); + if (constructor_type == error_mark_node) + return error_mark_node; + values = this->get_constructor_tree(context, constructor_type); + length_tree = size_int(this->vals()->size()); + } + + if (values == error_mark_node) + return error_mark_node; + + bool is_constant_initializer = TREE_CONSTANT(values); + + // We have to copy the initial values into heap memory if we are in + // a function or if the values are not constants. We also have to + // copy them if they may contain pointers in a non-constant context, + // as otherwise the garbage collector won't see them. + bool copy_to_heap = (context->function() != NULL + || !is_constant_initializer + || (element_type->has_pointer() + && !context->is_const())); + + if (is_constant_initializer) + { + tree tmp = build_decl(this->location(), VAR_DECL, + create_tmp_var_name("C"), TREE_TYPE(values)); + DECL_EXTERNAL(tmp) = 0; + TREE_PUBLIC(tmp) = 0; + TREE_STATIC(tmp) = 1; + DECL_ARTIFICIAL(tmp) = 1; + if (copy_to_heap) + { + // If we are not copying the value to the heap, we will only + // initialize the value once, so we can use this directly + // rather than copying it. In that case we can't make it + // read-only, because the program is permitted to change it. + TREE_READONLY(tmp) = 1; + TREE_CONSTANT(tmp) = 1; + } + DECL_INITIAL(tmp) = values; + rest_of_decl_compilation(tmp, 1, 0); + values = tmp; + } + + tree space; + tree set; + if (!copy_to_heap) + { + // the initializer will only run once. + space = build_fold_addr_expr(values); + set = NULL_TREE; + } + else + { + tree memsize = TYPE_SIZE_UNIT(TREE_TYPE(values)); + space = context->gogo()->allocate_memory(element_type, memsize, + this->location()); + space = save_expr(space); + + tree s = fold_convert(build_pointer_type(TREE_TYPE(values)), space); + tree ref = build_fold_indirect_ref_loc(this->location(), s); + TREE_THIS_NOTRAP(ref) = 1; + set = build2(MODIFY_EXPR, void_type_node, ref, values); + } + + // Build a constructor for the open array. + + tree type_tree = this->type()->get_tree(context->gogo()); + if (type_tree == error_mark_node) + return error_mark_node; + gcc_assert(TREE_CODE(type_tree) == RECORD_TYPE); + + VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 3); + + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + tree field = TYPE_FIELDS(type_tree); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__values") == 0); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), space); + + elt = VEC_quick_push(constructor_elt, init, NULL); + field = DECL_CHAIN(field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__count") == 0); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), length_tree); + + elt = VEC_quick_push(constructor_elt, init, NULL); + field = DECL_CHAIN(field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)),"__capacity") == 0); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), length_tree); + + tree constructor = build_constructor(type_tree, init); + if (constructor == error_mark_node) + return error_mark_node; + if (!copy_to_heap) + TREE_CONSTANT(constructor) = 1; + + if (set == NULL_TREE) + return constructor; + else + return build2(COMPOUND_EXPR, type_tree, set, constructor); +} + +// Make a slice composite literal. This is used by the type +// descriptor code. + +Expression* +Expression::make_slice_composite_literal(Type* type, Expression_list* vals, + source_location location) +{ + gcc_assert(type->is_open_array_type()); + return new Open_array_construction_expression(type, vals, location); +} + +// Construct a map. + +class Map_construction_expression : public Expression +{ + public: + Map_construction_expression(Type* type, Expression_list* vals, + source_location location) + : Expression(EXPRESSION_MAP_CONSTRUCTION, location), + type_(type), vals_(vals) + { gcc_assert(vals == NULL || vals->size() % 2 == 0); } + + protected: + int + do_traverse(Traverse* traverse); + + Type* + do_type() + { return this->type_; } + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return new Map_construction_expression(this->type_, this->vals_->copy(), + this->location()); + } + + tree + do_get_tree(Translate_context*); + + void + do_export(Export*) const; + + private: + // The type of the map to construct. + Type* type_; + // The list of values. + Expression_list* vals_; +}; + +// Traversal. + +int +Map_construction_expression::do_traverse(Traverse* traverse) +{ + if (this->vals_ != NULL + && this->vals_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (Type::traverse(this->type_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Final type determination. + +void +Map_construction_expression::do_determine_type(const Type_context*) +{ + if (this->vals_ == NULL) + return; + + Map_type* mt = this->type_->map_type(); + Type_context key_context(mt->key_type(), false); + Type_context val_context(mt->val_type(), false); + for (Expression_list::const_iterator pv = this->vals_->begin(); + pv != this->vals_->end(); + ++pv) + { + (*pv)->determine_type(&key_context); + ++pv; + (*pv)->determine_type(&val_context); + } +} + +// Check types. + +void +Map_construction_expression::do_check_types(Gogo*) +{ + if (this->vals_ == NULL) + return; + + Map_type* mt = this->type_->map_type(); + int i = 0; + Type* key_type = mt->key_type(); + Type* val_type = mt->val_type(); + for (Expression_list::const_iterator pv = this->vals_->begin(); + pv != this->vals_->end(); + ++pv, ++i) + { + if (!Type::are_assignable(key_type, (*pv)->type(), NULL)) + { + error_at((*pv)->location(), + "incompatible type for element %d key in map construction", + i + 1); + this->set_is_error(); + } + ++pv; + if (!Type::are_assignable(val_type, (*pv)->type(), NULL)) + { + error_at((*pv)->location(), + ("incompatible type for element %d value " + "in map construction"), + i + 1); + this->set_is_error(); + } + } +} + +// Return a tree for constructing a map. + +tree +Map_construction_expression::do_get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + source_location loc = this->location(); + + Map_type* mt = this->type_->map_type(); + + // Build a struct to hold the key and value. + tree struct_type = make_node(RECORD_TYPE); + + Type* key_type = mt->key_type(); + tree id = get_identifier("__key"); + tree key_type_tree = key_type->get_tree(gogo); + if (key_type_tree == error_mark_node) + return error_mark_node; + tree key_field = build_decl(loc, FIELD_DECL, id, key_type_tree); + DECL_CONTEXT(key_field) = struct_type; + TYPE_FIELDS(struct_type) = key_field; + + Type* val_type = mt->val_type(); + id = get_identifier("__val"); + tree val_type_tree = val_type->get_tree(gogo); + if (val_type_tree == error_mark_node) + return error_mark_node; + tree val_field = build_decl(loc, FIELD_DECL, id, val_type_tree); + DECL_CONTEXT(val_field) = struct_type; + DECL_CHAIN(key_field) = val_field; + + layout_type(struct_type); + + bool is_constant = true; + size_t i = 0; + tree valaddr; + tree make_tmp; + + if (this->vals_ == NULL || this->vals_->empty()) + { + valaddr = null_pointer_node; + make_tmp = NULL_TREE; + } + else + { + VEC(constructor_elt,gc)* values = VEC_alloc(constructor_elt, gc, + this->vals_->size() / 2); + + for (Expression_list::const_iterator pv = this->vals_->begin(); + pv != this->vals_->end(); + ++pv, ++i) + { + bool one_is_constant = true; + + VEC(constructor_elt,gc)* one = VEC_alloc(constructor_elt, gc, 2); + + constructor_elt* elt = VEC_quick_push(constructor_elt, one, NULL); + elt->index = key_field; + tree val_tree = (*pv)->get_tree(context); + elt->value = Expression::convert_for_assignment(context, key_type, + (*pv)->type(), + val_tree, loc); + if (elt->value == error_mark_node) + return error_mark_node; + if (!TREE_CONSTANT(elt->value)) + one_is_constant = false; + + ++pv; + + elt = VEC_quick_push(constructor_elt, one, NULL); + elt->index = val_field; + val_tree = (*pv)->get_tree(context); + elt->value = Expression::convert_for_assignment(context, val_type, + (*pv)->type(), + val_tree, loc); + if (elt->value == error_mark_node) + return error_mark_node; + if (!TREE_CONSTANT(elt->value)) + one_is_constant = false; + + elt = VEC_quick_push(constructor_elt, values, NULL); + elt->index = size_int(i); + elt->value = build_constructor(struct_type, one); + if (one_is_constant) + TREE_CONSTANT(elt->value) = 1; + else + is_constant = false; + } + + tree index_type = build_index_type(size_int(i - 1)); + tree array_type = build_array_type(struct_type, index_type); + tree init = build_constructor(array_type, values); + if (is_constant) + TREE_CONSTANT(init) = 1; + tree tmp; + if (current_function_decl != NULL) + { + tmp = create_tmp_var(array_type, get_name(array_type)); + DECL_INITIAL(tmp) = init; + make_tmp = fold_build1_loc(loc, DECL_EXPR, void_type_node, tmp); + TREE_ADDRESSABLE(tmp) = 1; + } + else + { + tmp = build_decl(loc, VAR_DECL, create_tmp_var_name("M"), array_type); + DECL_EXTERNAL(tmp) = 0; + TREE_PUBLIC(tmp) = 0; + TREE_STATIC(tmp) = 1; + DECL_ARTIFICIAL(tmp) = 1; + if (!TREE_CONSTANT(init)) + make_tmp = fold_build2_loc(loc, INIT_EXPR, void_type_node, tmp, + init); + else + { + TREE_READONLY(tmp) = 1; + TREE_CONSTANT(tmp) = 1; + DECL_INITIAL(tmp) = init; + make_tmp = NULL_TREE; + } + rest_of_decl_compilation(tmp, 1, 0); + } + + valaddr = build_fold_addr_expr(tmp); + } + + tree descriptor = gogo->map_descriptor(mt); + + tree type_tree = this->type_->get_tree(gogo); + if (type_tree == error_mark_node) + return error_mark_node; + + static tree construct_map_fndecl; + tree call = Gogo::call_builtin(&construct_map_fndecl, + loc, + "__go_construct_map", + 6, + type_tree, + TREE_TYPE(descriptor), + descriptor, + sizetype, + size_int(i), + sizetype, + TYPE_SIZE_UNIT(struct_type), + sizetype, + byte_position(val_field), + sizetype, + TYPE_SIZE_UNIT(TREE_TYPE(val_field)), + const_ptr_type_node, + fold_convert(const_ptr_type_node, valaddr)); + if (call == error_mark_node) + return error_mark_node; + + tree ret; + if (make_tmp == NULL) + ret = call; + else + ret = fold_build2_loc(loc, COMPOUND_EXPR, type_tree, make_tmp, call); + return ret; +} + +// Export an array construction. + +void +Map_construction_expression::do_export(Export* exp) const +{ + exp->write_c_string("convert("); + exp->write_type(this->type_); + for (Expression_list::const_iterator pv = this->vals_->begin(); + pv != this->vals_->end(); + ++pv) + { + exp->write_c_string(", "); + (*pv)->export_expression(exp); + } + exp->write_c_string(")"); +} + +// A general composite literal. This is lowered to a type specific +// version. + +class Composite_literal_expression : public Parser_expression +{ + public: + Composite_literal_expression(Type* type, int depth, bool has_keys, + Expression_list* vals, source_location location) + : Parser_expression(EXPRESSION_COMPOSITE_LITERAL, location), + type_(type), depth_(depth), vals_(vals), has_keys_(has_keys) + { } + + protected: + int + do_traverse(Traverse* traverse); + + Expression* + do_lower(Gogo*, Named_object*, int); + + Expression* + do_copy() + { + return new Composite_literal_expression(this->type_, this->depth_, + this->has_keys_, + (this->vals_ == NULL + ? NULL + : this->vals_->copy()), + this->location()); + } + + private: + Expression* + lower_struct(Gogo*, Type*); + + Expression* + lower_array(Type*); + + Expression* + make_array(Type*, Expression_list*); + + Expression* + lower_map(Gogo*, Named_object*, Type*); + + // The type of the composite literal. + Type* type_; + // The depth within a list of composite literals within a composite + // literal, when the type is omitted. + int depth_; + // The values to put in the composite literal. + Expression_list* vals_; + // If this is true, then VALS_ is a list of pairs: a key and a + // value. In an array initializer, a missing key will be NULL. + bool has_keys_; +}; + +// Traversal. + +int +Composite_literal_expression::do_traverse(Traverse* traverse) +{ + if (this->vals_ != NULL + && this->vals_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return Type::traverse(this->type_, traverse); +} + +// Lower a generic composite literal into a specific version based on +// the type. + +Expression* +Composite_literal_expression::do_lower(Gogo* gogo, Named_object* function, int) +{ + Type* type = this->type_; + + for (int depth = this->depth_; depth > 0; --depth) + { + if (type->array_type() != NULL) + type = type->array_type()->element_type(); + else if (type->map_type() != NULL) + type = type->map_type()->val_type(); + else + { + if (!type->is_error_type()) + error_at(this->location(), + ("may only omit types within composite literals " + "of slice, array, or map type")); + return Expression::make_error(this->location()); + } + } + + if (type->is_error_type()) + return Expression::make_error(this->location()); + else if (type->struct_type() != NULL) + return this->lower_struct(gogo, type); + else if (type->array_type() != NULL) + return this->lower_array(type); + else if (type->map_type() != NULL) + return this->lower_map(gogo, function, type); + else + { + error_at(this->location(), + ("expected struct, slice, array, or map type " + "for composite literal")); + return Expression::make_error(this->location()); + } +} + +// Lower a struct composite literal. + +Expression* +Composite_literal_expression::lower_struct(Gogo* gogo, Type* type) +{ + source_location location = this->location(); + Struct_type* st = type->struct_type(); + if (this->vals_ == NULL || !this->has_keys_) + return new Struct_construction_expression(type, this->vals_, location); + + size_t field_count = st->field_count(); + std::vector<Expression*> vals(field_count); + Expression_list::const_iterator p = this->vals_->begin(); + while (p != this->vals_->end()) + { + Expression* name_expr = *p; + + ++p; + gcc_assert(p != this->vals_->end()); + Expression* val = *p; + + ++p; + + if (name_expr == NULL) + { + error_at(val->location(), "mixture of field and value initializers"); + return Expression::make_error(location); + } + + bool bad_key = false; + std::string name; + const Named_object* no = NULL; + switch (name_expr->classification()) + { + case EXPRESSION_UNKNOWN_REFERENCE: + name = name_expr->unknown_expression()->name(); + break; + + case EXPRESSION_CONST_REFERENCE: + no = static_cast<Const_expression*>(name_expr)->named_object(); + break; + + case EXPRESSION_TYPE: + { + Type* t = name_expr->type(); + Named_type* nt = t->named_type(); + if (nt == NULL) + bad_key = true; + else + no = nt->named_object(); + } + break; + + case EXPRESSION_VAR_REFERENCE: + no = name_expr->var_expression()->named_object(); + break; + + case EXPRESSION_FUNC_REFERENCE: + no = name_expr->func_expression()->named_object(); + break; + + case EXPRESSION_UNARY: + // If there is a local variable around with the same name as + // the field, and this occurs in the closure, then the + // parser may turn the field reference into an indirection + // through the closure. FIXME: This is a mess. + { + bad_key = true; + Unary_expression* ue = static_cast<Unary_expression*>(name_expr); + if (ue->op() == OPERATOR_MULT) + { + Field_reference_expression* fre = + ue->operand()->field_reference_expression(); + if (fre != NULL) + { + Struct_type* st = + fre->expr()->type()->deref()->struct_type(); + if (st != NULL) + { + const Struct_field* sf = st->field(fre->field_index()); + name = sf->field_name(); + char buf[20]; + snprintf(buf, sizeof buf, "%u", fre->field_index()); + size_t buflen = strlen(buf); + if (name.compare(name.length() - buflen, buflen, buf) + == 0) + { + name = name.substr(0, name.length() - buflen); + bad_key = false; + } + } + } + } + } + break; + + default: + bad_key = true; + break; + } + if (bad_key) + { + error_at(name_expr->location(), "expected struct field name"); + return Expression::make_error(location); + } + + if (no != NULL) + { + name = no->name(); + + // A predefined name won't be packed. If it starts with a + // lower case letter we need to check for that case, because + // the field name will be packed. + if (!Gogo::is_hidden_name(name) + && name[0] >= 'a' + && name[0] <= 'z') + { + Named_object* gno = gogo->lookup_global(name.c_str()); + if (gno == no) + name = gogo->pack_hidden_name(name, false); + } + } + + unsigned int index; + const Struct_field* sf = st->find_local_field(name, &index); + if (sf == NULL) + { + error_at(name_expr->location(), "unknown field %qs in %qs", + Gogo::message_name(name).c_str(), + (type->named_type() != NULL + ? type->named_type()->message_name().c_str() + : "unnamed struct")); + return Expression::make_error(location); + } + if (vals[index] != NULL) + { + error_at(name_expr->location(), + "duplicate value for field %qs in %qs", + Gogo::message_name(name).c_str(), + (type->named_type() != NULL + ? type->named_type()->message_name().c_str() + : "unnamed struct")); + return Expression::make_error(location); + } + + vals[index] = val; + } + + Expression_list* list = new Expression_list; + list->reserve(field_count); + for (size_t i = 0; i < field_count; ++i) + list->push_back(vals[i]); + + return new Struct_construction_expression(type, list, location); +} + +// Lower an array composite literal. + +Expression* +Composite_literal_expression::lower_array(Type* type) +{ + source_location location = this->location(); + if (this->vals_ == NULL || !this->has_keys_) + return this->make_array(type, this->vals_); + + std::vector<Expression*> vals; + vals.reserve(this->vals_->size()); + unsigned long index = 0; + Expression_list::const_iterator p = this->vals_->begin(); + while (p != this->vals_->end()) + { + Expression* index_expr = *p; + + ++p; + gcc_assert(p != this->vals_->end()); + Expression* val = *p; + + ++p; + + if (index_expr != NULL) + { + mpz_t ival; + mpz_init(ival); + + Type* dummy; + if (!index_expr->integer_constant_value(true, ival, &dummy)) + { + mpz_clear(ival); + error_at(index_expr->location(), + "index expression is not integer constant"); + return Expression::make_error(location); + } + + if (mpz_sgn(ival) < 0) + { + mpz_clear(ival); + error_at(index_expr->location(), "index expression is negative"); + return Expression::make_error(location); + } + + index = mpz_get_ui(ival); + if (mpz_cmp_ui(ival, index) != 0) + { + mpz_clear(ival); + error_at(index_expr->location(), "index value overflow"); + return Expression::make_error(location); + } + + Named_type* ntype = Type::lookup_integer_type("int"); + Integer_type* inttype = ntype->integer_type(); + mpz_t max; + mpz_init_set_ui(max, 1); + mpz_mul_2exp(max, max, inttype->bits() - 1); + bool ok = mpz_cmp(ival, max) < 0; + mpz_clear(max); + if (!ok) + { + mpz_clear(ival); + error_at(index_expr->location(), "index value overflow"); + return Expression::make_error(location); + } + + mpz_clear(ival); + + // FIXME: Our representation isn't very good; this avoids + // thrashing. + if (index > 0x1000000) + { + error_at(index_expr->location(), "index too large for compiler"); + return Expression::make_error(location); + } + } + + if (index == vals.size()) + vals.push_back(val); + else + { + if (index > vals.size()) + { + vals.reserve(index + 32); + vals.resize(index + 1, static_cast<Expression*>(NULL)); + } + if (vals[index] != NULL) + { + error_at((index_expr != NULL + ? index_expr->location() + : val->location()), + "duplicate value for index %lu", + index); + return Expression::make_error(location); + } + vals[index] = val; + } + + ++index; + } + + size_t size = vals.size(); + Expression_list* list = new Expression_list; + list->reserve(size); + for (size_t i = 0; i < size; ++i) + list->push_back(vals[i]); + + return this->make_array(type, list); +} + +// Actually build the array composite literal. This handles +// [...]{...}. + +Expression* +Composite_literal_expression::make_array(Type* type, Expression_list* vals) +{ + source_location location = this->location(); + Array_type* at = type->array_type(); + if (at->length() != NULL && at->length()->is_nil_expression()) + { + size_t size = vals == NULL ? 0 : vals->size(); + mpz_t vlen; + mpz_init_set_ui(vlen, size); + Expression* elen = Expression::make_integer(&vlen, NULL, location); + mpz_clear(vlen); + at = Type::make_array_type(at->element_type(), elen); + type = at; + } + if (at->length() != NULL) + return new Fixed_array_construction_expression(type, vals, location); + else + return new Open_array_construction_expression(type, vals, location); +} + +// Lower a map composite literal. + +Expression* +Composite_literal_expression::lower_map(Gogo* gogo, Named_object* function, + Type* type) +{ + source_location location = this->location(); + if (this->vals_ != NULL) + { + if (!this->has_keys_) + { + error_at(location, "map composite literal must have keys"); + return Expression::make_error(location); + } + + for (Expression_list::iterator p = this->vals_->begin(); + p != this->vals_->end(); + p += 2) + { + if (*p == NULL) + { + ++p; + error_at((*p)->location(), + "map composite literal must have keys for every value"); + return Expression::make_error(location); + } + // Make sure we have lowered the key; it may not have been + // lowered in order to handle keys for struct composite + // literals. Lower it now to get the right error message. + if ((*p)->unknown_expression() != NULL) + { + (*p)->unknown_expression()->clear_is_composite_literal_key(); + gogo->lower_expression(function, &*p); + gcc_assert((*p)->is_error_expression()); + return Expression::make_error(location); + } + } + } + + return new Map_construction_expression(type, this->vals_, location); +} + +// Make a composite literal expression. + +Expression* +Expression::make_composite_literal(Type* type, int depth, bool has_keys, + Expression_list* vals, + source_location location) +{ + return new Composite_literal_expression(type, depth, has_keys, vals, + location); +} + +// Return whether this expression is a composite literal. + +bool +Expression::is_composite_literal() const +{ + switch (this->classification_) + { + case EXPRESSION_COMPOSITE_LITERAL: + case EXPRESSION_STRUCT_CONSTRUCTION: + case EXPRESSION_FIXED_ARRAY_CONSTRUCTION: + case EXPRESSION_OPEN_ARRAY_CONSTRUCTION: + case EXPRESSION_MAP_CONSTRUCTION: + return true; + default: + return false; + } +} + +// Return whether this expression is a composite literal which is not +// constant. + +bool +Expression::is_nonconstant_composite_literal() const +{ + switch (this->classification_) + { + case EXPRESSION_STRUCT_CONSTRUCTION: + { + const Struct_construction_expression *psce = + static_cast<const Struct_construction_expression*>(this); + return !psce->is_constant_struct(); + } + case EXPRESSION_FIXED_ARRAY_CONSTRUCTION: + { + const Fixed_array_construction_expression *pace = + static_cast<const Fixed_array_construction_expression*>(this); + return !pace->is_constant_array(); + } + case EXPRESSION_OPEN_ARRAY_CONSTRUCTION: + { + const Open_array_construction_expression *pace = + static_cast<const Open_array_construction_expression*>(this); + return !pace->is_constant_array(); + } + case EXPRESSION_MAP_CONSTRUCTION: + return true; + default: + return false; + } +} + +// Return true if this is a reference to a local variable. + +bool +Expression::is_local_variable() const +{ + const Var_expression* ve = this->var_expression(); + if (ve == NULL) + return false; + const Named_object* no = ve->named_object(); + return (no->is_result_variable() + || (no->is_variable() && !no->var_value()->is_global())); +} + +// Class Type_guard_expression. + +// Traversal. + +int +Type_guard_expression::do_traverse(Traverse* traverse) +{ + if (Expression::traverse(&this->expr_, traverse) == TRAVERSE_EXIT + || Type::traverse(this->type_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Check types of a type guard expression. The expression must have +// an interface type, but the actual type conversion is checked at run +// time. + +void +Type_guard_expression::do_check_types(Gogo*) +{ + // 6g permits using a type guard with unsafe.pointer; we are + // compatible. + Type* expr_type = this->expr_->type(); + if (expr_type->is_unsafe_pointer_type()) + { + if (this->type_->points_to() == NULL + && (this->type_->integer_type() == NULL + || (this->type_->forwarded() + != Type::lookup_integer_type("uintptr")))) + this->report_error(_("invalid unsafe.Pointer conversion")); + } + else if (this->type_->is_unsafe_pointer_type()) + { + if (expr_type->points_to() == NULL + && (expr_type->integer_type() == NULL + || (expr_type->forwarded() + != Type::lookup_integer_type("uintptr")))) + this->report_error(_("invalid unsafe.Pointer conversion")); + } + else if (expr_type->interface_type() == NULL) + { + if (!expr_type->is_error_type() && !this->type_->is_error_type()) + this->report_error(_("type assertion only valid for interface types")); + this->set_is_error(); + } + else if (this->type_->interface_type() == NULL) + { + std::string reason; + if (!expr_type->interface_type()->implements_interface(this->type_, + &reason)) + { + if (!this->type_->is_error_type()) + { + if (reason.empty()) + this->report_error(_("impossible type assertion: " + "type does not implement interface")); + else + error_at(this->location(), + ("impossible type assertion: " + "type does not implement interface (%s)"), + reason.c_str()); + } + this->set_is_error(); + } + } +} + +// Return a tree for a type guard expression. + +tree +Type_guard_expression::do_get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + tree expr_tree = this->expr_->get_tree(context); + if (expr_tree == error_mark_node) + return error_mark_node; + Type* expr_type = this->expr_->type(); + if ((this->type_->is_unsafe_pointer_type() + && (expr_type->points_to() != NULL + || expr_type->integer_type() != NULL)) + || (expr_type->is_unsafe_pointer_type() + && this->type_->points_to() != NULL)) + return convert_to_pointer(this->type_->get_tree(gogo), expr_tree); + else if (expr_type->is_unsafe_pointer_type() + && this->type_->integer_type() != NULL) + return convert_to_integer(this->type_->get_tree(gogo), expr_tree); + else if (this->type_->interface_type() != NULL) + return Expression::convert_interface_to_interface(context, this->type_, + this->expr_->type(), + expr_tree, true, + this->location()); + else + return Expression::convert_for_assignment(context, this->type_, + this->expr_->type(), expr_tree, + this->location()); +} + +// Make a type guard expression. + +Expression* +Expression::make_type_guard(Expression* expr, Type* type, + source_location location) +{ + return new Type_guard_expression(expr, type, location); +} + +// Class Heap_composite_expression. + +// When you take the address of a composite literal, it is allocated +// on the heap. This class implements that. + +class Heap_composite_expression : public Expression +{ + public: + Heap_composite_expression(Expression* expr, source_location location) + : Expression(EXPRESSION_HEAP_COMPOSITE, location), + expr_(expr) + { } + + protected: + int + do_traverse(Traverse* traverse) + { return Expression::traverse(&this->expr_, traverse); } + + Type* + do_type() + { return Type::make_pointer_type(this->expr_->type()); } + + void + do_determine_type(const Type_context*) + { this->expr_->determine_type_no_context(); } + + Expression* + do_copy() + { + return Expression::make_heap_composite(this->expr_->copy(), + this->location()); + } + + tree + do_get_tree(Translate_context*); + + // We only export global objects, and the parser does not generate + // this in global scope. + void + do_export(Export*) const + { gcc_unreachable(); } + + private: + // The composite literal which is being put on the heap. + Expression* expr_; +}; + +// Return a tree which allocates a composite literal on the heap. + +tree +Heap_composite_expression::do_get_tree(Translate_context* context) +{ + tree expr_tree = this->expr_->get_tree(context); + if (expr_tree == error_mark_node) + return error_mark_node; + tree expr_size = TYPE_SIZE_UNIT(TREE_TYPE(expr_tree)); + gcc_assert(TREE_CODE(expr_size) == INTEGER_CST); + tree space = context->gogo()->allocate_memory(this->expr_->type(), + expr_size, this->location()); + space = fold_convert(build_pointer_type(TREE_TYPE(expr_tree)), space); + space = save_expr(space); + tree ref = build_fold_indirect_ref_loc(this->location(), space); + TREE_THIS_NOTRAP(ref) = 1; + tree ret = build2(COMPOUND_EXPR, TREE_TYPE(space), + build2(MODIFY_EXPR, void_type_node, ref, expr_tree), + space); + SET_EXPR_LOCATION(ret, this->location()); + return ret; +} + +// Allocate a composite literal on the heap. + +Expression* +Expression::make_heap_composite(Expression* expr, source_location location) +{ + return new Heap_composite_expression(expr, location); +} + +// Class Receive_expression. + +// Return the type of a receive expression. + +Type* +Receive_expression::do_type() +{ + Channel_type* channel_type = this->channel_->type()->channel_type(); + if (channel_type == NULL) + return Type::make_error_type(); + return channel_type->element_type(); +} + +// Check types for a receive expression. + +void +Receive_expression::do_check_types(Gogo*) +{ + Type* type = this->channel_->type(); + if (type->is_error_type()) + { + this->set_is_error(); + return; + } + if (type->channel_type() == NULL) + { + this->report_error(_("expected channel")); + return; + } + if (!type->channel_type()->may_receive()) + { + this->report_error(_("invalid receive on send-only channel")); + return; + } +} + +// Get a tree for a receive expression. + +tree +Receive_expression::do_get_tree(Translate_context* context) +{ + Channel_type* channel_type = this->channel_->type()->channel_type(); + if (channel_type == NULL) + { + gcc_assert(this->channel_->type()->is_error_type()); + return error_mark_node; + } + Type* element_type = channel_type->element_type(); + tree element_type_tree = element_type->get_tree(context->gogo()); + + tree channel = this->channel_->get_tree(context); + if (element_type_tree == error_mark_node || channel == error_mark_node) + return error_mark_node; + + return Gogo::receive_from_channel(element_type_tree, channel, + this->for_select_, this->location()); +} + +// Make a receive expression. + +Receive_expression* +Expression::make_receive(Expression* channel, source_location location) +{ + return new Receive_expression(channel, location); +} + +// Class Send_expression. + +// Traversal. + +int +Send_expression::do_traverse(Traverse* traverse) +{ + if (Expression::traverse(&this->channel_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return Expression::traverse(&this->val_, traverse); +} + +// Get the type. + +Type* +Send_expression::do_type() +{ + if (this->is_value_discarded_) + return Type::make_void_type(); + else + return Type::lookup_bool_type(); +} + +// Set types. + +void +Send_expression::do_determine_type(const Type_context*) +{ + this->channel_->determine_type_no_context(); + + Type* type = this->channel_->type(); + Type_context subcontext; + if (type->channel_type() != NULL) + subcontext.type = type->channel_type()->element_type(); + this->val_->determine_type(&subcontext); +} + +// Check types. + +void +Send_expression::do_check_types(Gogo*) +{ + Type* type = this->channel_->type(); + if (type->is_error_type()) + { + this->set_is_error(); + return; + } + Channel_type* channel_type = type->channel_type(); + if (channel_type == NULL) + { + error_at(this->location(), "left operand of %<<-%> must be channel"); + this->set_is_error(); + return; + } + Type* element_type = channel_type->element_type(); + if (element_type != NULL + && !Type::are_assignable(element_type, this->val_->type(), NULL)) + { + this->report_error(_("incompatible types in send")); + return; + } + if (!channel_type->may_send()) + { + this->report_error(_("invalid send on receive-only channel")); + return; + } +} + +// Get a tree for a send expression. + +tree +Send_expression::do_get_tree(Translate_context* context) +{ + tree channel = this->channel_->get_tree(context); + tree val = this->val_->get_tree(context); + if (channel == error_mark_node || val == error_mark_node) + return error_mark_node; + Channel_type* channel_type = this->channel_->type()->channel_type(); + val = Expression::convert_for_assignment(context, + channel_type->element_type(), + this->val_->type(), + val, + this->location()); + return Gogo::send_on_channel(channel, val, this->is_value_discarded_, + this->for_select_, this->location()); +} + +// Make a send expression + +Send_expression* +Expression::make_send(Expression* channel, Expression* val, + source_location location) +{ + return new Send_expression(channel, val, location); +} + +// An expression which evaluates to a pointer to the type descriptor +// of a type. + +class Type_descriptor_expression : public Expression +{ + public: + Type_descriptor_expression(Type* type, source_location location) + : Expression(EXPRESSION_TYPE_DESCRIPTOR, location), + type_(type) + { } + + protected: + Type* + do_type() + { return Type::make_type_descriptor_ptr_type(); } + + void + do_determine_type(const Type_context*) + { } + + Expression* + do_copy() + { return this; } + + tree + do_get_tree(Translate_context* context) + { return this->type_->type_descriptor_pointer(context->gogo()); } + + private: + // The type for which this is the descriptor. + Type* type_; +}; + +// Make a type descriptor expression. + +Expression* +Expression::make_type_descriptor(Type* type, source_location location) +{ + return new Type_descriptor_expression(type, location); +} + +// An expression which evaluates to some characteristic of a type. +// This is only used to initialize fields of a type descriptor. Using +// a new expression class is slightly inefficient but gives us a good +// separation between the frontend and the middle-end with regard to +// how types are laid out. + +class Type_info_expression : public Expression +{ + public: + Type_info_expression(Type* type, Type_info type_info) + : Expression(EXPRESSION_TYPE_INFO, BUILTINS_LOCATION), + type_(type), type_info_(type_info) + { } + + protected: + Type* + do_type(); + + void + do_determine_type(const Type_context*) + { } + + Expression* + do_copy() + { return this; } + + tree + do_get_tree(Translate_context* context); + + private: + // The type for which we are getting information. + Type* type_; + // What information we want. + Type_info type_info_; +}; + +// The type is chosen to match what the type descriptor struct +// expects. + +Type* +Type_info_expression::do_type() +{ + switch (this->type_info_) + { + case TYPE_INFO_SIZE: + return Type::lookup_integer_type("uintptr"); + case TYPE_INFO_ALIGNMENT: + case TYPE_INFO_FIELD_ALIGNMENT: + return Type::lookup_integer_type("uint8"); + default: + gcc_unreachable(); + } +} + +// Return type information in GENERIC. + +tree +Type_info_expression::do_get_tree(Translate_context* context) +{ + tree type_tree = this->type_->get_tree(context->gogo()); + if (type_tree == error_mark_node) + return error_mark_node; + + tree val_type_tree = this->type()->get_tree(context->gogo()); + gcc_assert(val_type_tree != error_mark_node); + + if (this->type_info_ == TYPE_INFO_SIZE) + return fold_convert_loc(BUILTINS_LOCATION, val_type_tree, + TYPE_SIZE_UNIT(type_tree)); + else + { + unsigned int val; + if (this->type_info_ == TYPE_INFO_ALIGNMENT) + val = go_type_alignment(type_tree); + else + val = go_field_alignment(type_tree); + return build_int_cstu(val_type_tree, val); + } +} + +// Make a type info expression. + +Expression* +Expression::make_type_info(Type* type, Type_info type_info) +{ + return new Type_info_expression(type, type_info); +} + +// An expression which evaluates to the offset of a field within a +// struct. This, like Type_info_expression, q.v., is only used to +// initialize fields of a type descriptor. + +class Struct_field_offset_expression : public Expression +{ + public: + Struct_field_offset_expression(Struct_type* type, const Struct_field* field) + : Expression(EXPRESSION_STRUCT_FIELD_OFFSET, BUILTINS_LOCATION), + type_(type), field_(field) + { } + + protected: + Type* + do_type() + { return Type::lookup_integer_type("uintptr"); } + + void + do_determine_type(const Type_context*) + { } + + Expression* + do_copy() + { return this; } + + tree + do_get_tree(Translate_context* context); + + private: + // The type of the struct. + Struct_type* type_; + // The field. + const Struct_field* field_; +}; + +// Return a struct field offset in GENERIC. + +tree +Struct_field_offset_expression::do_get_tree(Translate_context* context) +{ + tree type_tree = this->type_->get_tree(context->gogo()); + if (type_tree == error_mark_node) + return error_mark_node; + + tree val_type_tree = this->type()->get_tree(context->gogo()); + gcc_assert(val_type_tree != error_mark_node); + + const Struct_field_list* fields = this->type_->fields(); + tree struct_field_tree = TYPE_FIELDS(type_tree); + Struct_field_list::const_iterator p; + for (p = fields->begin(); + p != fields->end(); + ++p, struct_field_tree = DECL_CHAIN(struct_field_tree)) + { + gcc_assert(struct_field_tree != NULL_TREE); + if (&*p == this->field_) + break; + } + gcc_assert(&*p == this->field_); + + return fold_convert_loc(BUILTINS_LOCATION, val_type_tree, + byte_position(struct_field_tree)); +} + +// Make an expression for a struct field offset. + +Expression* +Expression::make_struct_field_offset(Struct_type* type, + const Struct_field* field) +{ + return new Struct_field_offset_expression(type, field); +} + +// An expression which evaluates to the address of an unnamed label. + +class Label_addr_expression : public Expression +{ + public: + Label_addr_expression(Label* label, source_location location) + : Expression(EXPRESSION_LABEL_ADDR, location), + label_(label) + { } + + protected: + Type* + do_type() + { return Type::make_pointer_type(Type::make_void_type()); } + + void + do_determine_type(const Type_context*) + { } + + Expression* + do_copy() + { return new Label_addr_expression(this->label_, this->location()); } + + tree + do_get_tree(Translate_context*) + { return this->label_->get_addr(this->location()); } + + private: + // The label whose address we are taking. + Label* label_; +}; + +// Make an expression for the address of an unnamed label. + +Expression* +Expression::make_label_addr(Label* label, source_location location) +{ + return new Label_addr_expression(label, location); +} + +// Import an expression. This comes at the end in order to see the +// various class definitions. + +Expression* +Expression::import_expression(Import* imp) +{ + int c = imp->peek_char(); + if (imp->match_c_string("- ") + || imp->match_c_string("! ") + || imp->match_c_string("^ ")) + return Unary_expression::do_import(imp); + else if (c == '(') + return Binary_expression::do_import(imp); + else if (imp->match_c_string("true") + || imp->match_c_string("false")) + return Boolean_expression::do_import(imp); + else if (c == '"') + return String_expression::do_import(imp); + else if (c == '-' || (c >= '0' && c <= '9')) + { + // This handles integers, floats and complex constants. + return Integer_expression::do_import(imp); + } + else if (imp->match_c_string("nil")) + return Nil_expression::do_import(imp); + else if (imp->match_c_string("convert")) + return Type_conversion_expression::do_import(imp); + else + { + error_at(imp->location(), "import error: expected expression"); + return Expression::make_error(imp->location()); + } +} + +// Class Expression_list. + +// Traverse the list. + +int +Expression_list::traverse(Traverse* traverse) +{ + for (Expression_list::iterator p = this->begin(); + p != this->end(); + ++p) + { + if (*p != NULL) + { + if (Expression::traverse(&*p, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + } + return TRAVERSE_CONTINUE; +} + +// Copy the list. + +Expression_list* +Expression_list::copy() +{ + Expression_list* ret = new Expression_list(); + for (Expression_list::iterator p = this->begin(); + p != this->end(); + ++p) + { + if (*p == NULL) + ret->push_back(NULL); + else + ret->push_back((*p)->copy()); + } + return ret; +} + +// Return whether an expression list has an error expression. + +bool +Expression_list::contains_error() const +{ + for (Expression_list::const_iterator p = this->begin(); + p != this->end(); + ++p) + if (*p != NULL && (*p)->is_error_expression()) + return true; + return false; +} diff --git a/gcc/go/gofrontend/expressions.h b/gcc/go/gofrontend/expressions.h new file mode 100644 index 000000000..1dc408d55 --- /dev/null +++ b/gcc/go/gofrontend/expressions.h @@ -0,0 +1,1923 @@ +// expressions.h -- Go frontend expression handling. -*- C++ -*- + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef GO_EXPRESSIONS_H +#define GO_EXPRESSIONS_H + +#include <gmp.h> +#include <mpfr.h> + +#include "operator.h" + +class Gogo; +class Translate_context; +class Traverse; +class Type; +struct Type_context; +class Function_type; +class Map_type; +class Struct_type; +class Struct_field; +class Expression_list; +class Var_expression; +class Temporary_reference_expression; +class String_expression; +class Binary_expression; +class Call_expression; +class Func_expression; +class Unknown_expression; +class Index_expression; +class Map_index_expression; +class Bound_method_expression; +class Field_reference_expression; +class Interface_field_reference_expression; +class Type_guard_expression; +class Receive_expression; +class Send_expression; +class Named_object; +class Export; +class Import; +class Temporary_statement; +class Label; + +// The base class for all expressions. + +class Expression +{ + public: + // The types of expressions. + enum Expression_classification + { + EXPRESSION_ERROR, + EXPRESSION_TYPE, + EXPRESSION_UNARY, + EXPRESSION_BINARY, + EXPRESSION_CONST_REFERENCE, + EXPRESSION_VAR_REFERENCE, + EXPRESSION_TEMPORARY_REFERENCE, + EXPRESSION_SINK, + EXPRESSION_FUNC_REFERENCE, + EXPRESSION_UNKNOWN_REFERENCE, + EXPRESSION_BOOLEAN, + EXPRESSION_STRING, + EXPRESSION_INTEGER, + EXPRESSION_FLOAT, + EXPRESSION_COMPLEX, + EXPRESSION_NIL, + EXPRESSION_IOTA, + EXPRESSION_CALL, + EXPRESSION_CALL_RESULT, + EXPRESSION_BOUND_METHOD, + EXPRESSION_INDEX, + EXPRESSION_ARRAY_INDEX, + EXPRESSION_STRING_INDEX, + EXPRESSION_MAP_INDEX, + EXPRESSION_SELECTOR, + EXPRESSION_FIELD_REFERENCE, + EXPRESSION_INTERFACE_FIELD_REFERENCE, + EXPRESSION_ALLOCATION, + EXPRESSION_MAKE, + EXPRESSION_TYPE_GUARD, + EXPRESSION_CONVERSION, + EXPRESSION_STRUCT_CONSTRUCTION, + EXPRESSION_FIXED_ARRAY_CONSTRUCTION, + EXPRESSION_OPEN_ARRAY_CONSTRUCTION, + EXPRESSION_MAP_CONSTRUCTION, + EXPRESSION_COMPOSITE_LITERAL, + EXPRESSION_HEAP_COMPOSITE, + EXPRESSION_RECEIVE, + EXPRESSION_SEND, + EXPRESSION_TYPE_DESCRIPTOR, + EXPRESSION_TYPE_INFO, + EXPRESSION_STRUCT_FIELD_OFFSET, + EXPRESSION_LABEL_ADDR + }; + + Expression(Expression_classification, source_location); + + virtual ~Expression(); + + // Make an error expression. This is used when a parse error occurs + // to prevent cascading errors. + static Expression* + make_error(source_location); + + // Make an expression which is really a type. This is used during + // parsing. + static Expression* + make_type(Type*, source_location); + + // Make a unary expression. + static Expression* + make_unary(Operator, Expression*, source_location); + + // Make a binary expression. + static Expression* + make_binary(Operator, Expression*, Expression*, source_location); + + // Make a reference to a constant in an expression. + static Expression* + make_const_reference(Named_object*, source_location); + + // Make a reference to a variable in an expression. + static Expression* + make_var_reference(Named_object*, source_location); + + // Make a reference to a temporary variable. Temporary variables + // are always created by a single statement, which is what we use to + // refer to them. + static Expression* + make_temporary_reference(Temporary_statement*, source_location); + + // Make a sink expression--a reference to the blank identifier _. + static Expression* + make_sink(source_location); + + // Make a reference to a function in an expression. + static Expression* + make_func_reference(Named_object*, Expression* closure, source_location); + + // Make a reference to an unknown name. In a correct program this + // will always be lowered to a real const/var/func reference. + static Expression* + make_unknown_reference(Named_object*, source_location); + + // Make a constant bool expression. + static Expression* + make_boolean(bool val, source_location); + + // Make a constant string expression. + static Expression* + make_string(const std::string&, source_location); + + // Make a constant integer expression. TYPE should be NULL for an + // abstract type. + static Expression* + make_integer(const mpz_t*, Type*, source_location); + + // Make a constant float expression. TYPE should be NULL for an + // abstract type. + static Expression* + make_float(const mpfr_t*, Type*, source_location); + + // Make a constant complex expression. TYPE should be NULL for an + // abstract type. + static Expression* + make_complex(const mpfr_t* real, const mpfr_t* imag, Type*, source_location); + + // Make a nil expression. + static Expression* + make_nil(source_location); + + // Make an iota expression. This is used for the predeclared + // constant iota. + static Expression* + make_iota(); + + // Make a call expression. + static Call_expression* + make_call(Expression* func, Expression_list* args, bool is_varargs, + source_location); + + // Make a reference to a specific result of a call expression which + // returns a tuple. + static Expression* + make_call_result(Call_expression*, unsigned int index); + + // Make an expression which is a method bound to its first + // parameter. + static Bound_method_expression* + make_bound_method(Expression* object, Expression* method, source_location); + + // Make an index or slice expression. This is a parser expression + // which represents LEFT[START:END]. END may be NULL, meaning an + // index rather than a slice. At parse time we may not know the + // type of LEFT. After parsing this is lowered to an array index, a + // string index, or a map index. + static Expression* + make_index(Expression* left, Expression* start, Expression* end, + source_location); + + // Make an array index expression. END may be NULL, in which case + // this is an lvalue. + static Expression* + make_array_index(Expression* array, Expression* start, Expression* end, + source_location); + + // Make a string index expression. END may be NULL. This is never + // an lvalue. + static Expression* + make_string_index(Expression* string, Expression* start, Expression* end, + source_location); + + // Make a map index expression. This is an lvalue. + static Map_index_expression* + make_map_index(Expression* map, Expression* val, source_location); + + // Make a selector. This is a parser expression which represents + // LEFT.NAME. At parse time we may not know the type of the left + // hand side. + static Expression* + make_selector(Expression* left, const std::string& name, source_location); + + // Make a reference to a field in a struct. + static Field_reference_expression* + make_field_reference(Expression*, unsigned int field_index, source_location); + + // Make a reference to a field of an interface, with an associated + // object. + static Expression* + make_interface_field_reference(Expression*, const std::string&, + source_location); + + // Make an allocation expression. + static Expression* + make_allocation(Type*, source_location); + + // Make a call to the builtin function make. + static Expression* + make_make(Type*, Expression_list*, source_location); + + // Make a type guard expression. + static Expression* + make_type_guard(Expression*, Type*, source_location); + + // Make a type cast expression. + static Expression* + make_cast(Type*, Expression*, source_location); + + // Make a composite literal. The DEPTH parameter is how far down we + // are in a list of composite literals with omitted types. + static Expression* + make_composite_literal(Type*, int depth, bool has_keys, Expression_list*, + source_location); + + // Make a struct composite literal. + static Expression* + make_struct_composite_literal(Type*, Expression_list*, source_location); + + // Make a slice composite literal. + static Expression* + make_slice_composite_literal(Type*, Expression_list*, source_location); + + // Take a composite literal and allocate it on the heap. + static Expression* + make_heap_composite(Expression*, source_location); + + // Make a receive expression. VAL is NULL for a unary receive. + static Receive_expression* + make_receive(Expression* channel, source_location); + + // Make a send expression. + static Send_expression* + make_send(Expression* channel, Expression* val, source_location); + + // Make an expression which evaluates to the type descriptor of a + // type. + static Expression* + make_type_descriptor(Type* type, source_location); + + // Make an expression which evaluates to some characteristic of a + // type. These are only used for type descriptors, so there is no + // location parameter. + enum Type_info + { + // The size of a value of the type. + TYPE_INFO_SIZE, + // The required alignment of a value of the type. + TYPE_INFO_ALIGNMENT, + // The required alignment of a value of the type when used as a + // field in a struct. + TYPE_INFO_FIELD_ALIGNMENT + }; + + static Expression* + make_type_info(Type* type, Type_info); + + // Make an expression which evaluates to the offset of a field in a + // struct. This is only used for type descriptors, so there is no + // location parameter. + static Expression* + make_struct_field_offset(Struct_type*, const Struct_field*); + + // Make an expression which evaluates to the address of an unnamed + // label. + static Expression* + make_label_addr(Label*, source_location); + + // Return the expression classification. + Expression_classification + classification() const + { return this->classification_; } + + // Return the location of the expression. + source_location + location() const + { return this->location_; } + + // Return whether this is a constant expression. + bool + is_constant() const + { return this->do_is_constant(); } + + // If this is not a constant expression with integral type, return + // false. If it is one, return true, and set VAL to the value. VAL + // should already be initialized. If this returns true, it sets + // *PTYPE to the type of the value, or NULL for an abstract type. + // If IOTA_IS_CONSTANT is true, then an iota expression is assumed + // to have its final value. + bool + integer_constant_value(bool iota_is_constant, mpz_t val, Type** ptype) const; + + // If this is not a constant expression with floating point type, + // return false. If it is one, return true, and set VAL to the + // value. VAL should already be initialized. If this returns true, + // it sets *PTYPE to the type of the value, or NULL for an abstract + // type. + bool + float_constant_value(mpfr_t val, Type** ptype) const; + + // If this is not a constant expression with complex type, return + // false. If it is one, return true, and set REAL and IMAG to the + // value. REAL and IMAG should already be initialized. If this + // return strue, it sets *PTYPE to the type of the value, or NULL + // for an abstract type. + bool + complex_constant_value(mpfr_t real, mpfr_t imag, Type** ptype) const; + + // If this is not a constant expression with string type, return + // false. If it is one, return true, and set VAL to the value. + bool + string_constant_value(std::string* val) const + { return this->do_string_constant_value(val); } + + // This is called by the parser if the value of this expression is + // being discarded. This issues warnings about computed values + // being unused, and handles send expressions which act differently + // depending upon whether the value is used. + void + discarding_value() + { this->do_discarding_value(); } + + // Return whether this is an error expression. + bool + is_error_expression() const + { return this->classification_ == EXPRESSION_ERROR; } + + // Return whether this expression really represents a type. + bool + is_type_expression() const + { return this->classification_ == EXPRESSION_TYPE; } + + // If this is a variable reference, return the Var_expression + // structure. Otherwise, return NULL. This is a controlled dynamic + // cast. + Var_expression* + var_expression() + { return this->convert<Var_expression, EXPRESSION_VAR_REFERENCE>(); } + + const Var_expression* + var_expression() const + { return this->convert<const Var_expression, EXPRESSION_VAR_REFERENCE>(); } + + // If this is a reference to a temporary variable, return the + // Temporary_reference_expression. Otherwise, return NULL. + Temporary_reference_expression* + temporary_reference_expression() + { + return this->convert<Temporary_reference_expression, + EXPRESSION_TEMPORARY_REFERENCE>(); + } + + // Return whether this is a sink expression. + bool + is_sink_expression() const + { return this->classification_ == EXPRESSION_SINK; } + + // If this is a string expression, return the String_expression + // structure. Otherwise, return NULL. + String_expression* + string_expression() + { return this->convert<String_expression, EXPRESSION_STRING>(); } + + // Return whether this is the expression nil. + bool + is_nil_expression() const + { return this->classification_ == EXPRESSION_NIL; } + + // If this is an indirection through a pointer, return the + // expression being pointed through. Otherwise return this. + Expression* + deref(); + + // If this is a binary expression, return the Binary_expression + // structure. Otherwise return NULL. + Binary_expression* + binary_expression() + { return this->convert<Binary_expression, EXPRESSION_BINARY>(); } + + // If this is a call expression, return the Call_expression + // structure. Otherwise, return NULL. This is a controlled dynamic + // cast. + Call_expression* + call_expression() + { return this->convert<Call_expression, EXPRESSION_CALL>(); } + + // If this is an expression which refers to a function, return the + // Func_expression structure. Otherwise, return NULL. + Func_expression* + func_expression() + { return this->convert<Func_expression, EXPRESSION_FUNC_REFERENCE>(); } + + const Func_expression* + func_expression() const + { return this->convert<const Func_expression, EXPRESSION_FUNC_REFERENCE>(); } + + // If this is an expression which refers to an unknown name, return + // the Unknown_expression structure. Otherwise, return NULL. + Unknown_expression* + unknown_expression() + { return this->convert<Unknown_expression, EXPRESSION_UNKNOWN_REFERENCE>(); } + + const Unknown_expression* + unknown_expression() const + { + return this->convert<const Unknown_expression, + EXPRESSION_UNKNOWN_REFERENCE>(); + } + + // If this is an index expression, return the Index_expression + // structure. Otherwise, return NULL. + Index_expression* + index_expression() + { return this->convert<Index_expression, EXPRESSION_INDEX>(); } + + // If this is an expression which refers to indexing in a map, + // return the Map_index_expression structure. Otherwise, return + // NULL. + Map_index_expression* + map_index_expression() + { return this->convert<Map_index_expression, EXPRESSION_MAP_INDEX>(); } + + // If this is a bound method expression, return the + // Bound_method_expression structure. Otherwise, return NULL. + Bound_method_expression* + bound_method_expression() + { return this->convert<Bound_method_expression, EXPRESSION_BOUND_METHOD>(); } + + // If this is a reference to a field in a struct, return the + // Field_reference_expression structure. Otherwise, return NULL. + Field_reference_expression* + field_reference_expression() + { + return this->convert<Field_reference_expression, + EXPRESSION_FIELD_REFERENCE>(); + } + + // If this is a reference to a field in an interface, return the + // Interface_field_reference_expression structure. Otherwise, + // return NULL. + Interface_field_reference_expression* + interface_field_reference_expression() + { + return this->convert<Interface_field_reference_expression, + EXPRESSION_INTERFACE_FIELD_REFERENCE>(); + } + + // If this is a type guard expression, return the + // Type_guard_expression structure. Otherwise, return NULL. + Type_guard_expression* + type_guard_expression() + { return this->convert<Type_guard_expression, EXPRESSION_TYPE_GUARD>(); } + + // If this is a receive expression, return the Receive_expression + // structure. Otherwise, return NULL. + Receive_expression* + receive_expression() + { return this->convert<Receive_expression, EXPRESSION_RECEIVE>(); } + + // Return true if this is a composite literal. + bool + is_composite_literal() const; + + // Return true if this is a composite literal which is not constant. + bool + is_nonconstant_composite_literal() const; + + // Return true if this is a reference to a local variable. + bool + is_local_variable() const; + + // Traverse an expression. + static int + traverse(Expression**, Traverse*); + + // Traverse subexpressions of this expression. + int + traverse_subexpressions(Traverse*); + + // Lower an expression. This is called immediately after parsing. + // IOTA_VALUE is the value that we should give to any iota + // expressions. This function must resolve expressions which could + // not be fully parsed into their final form. It returns the same + // Expression or a new one. + Expression* + lower(Gogo* gogo, Named_object* function, int iota_value) + { return this->do_lower(gogo, function, iota_value); } + + // Determine the real type of an expression with abstract integer, + // floating point, or complex type. TYPE_CONTEXT describes the + // expected type. + void + determine_type(const Type_context*); + + // Check types in an expression. + void + check_types(Gogo* gogo) + { this->do_check_types(gogo); } + + // Determine the type when there is no context. + void + determine_type_no_context(); + + // Return the current type of the expression. This may be changed + // by determine_type. + Type* + type() + { return this->do_type(); } + + // Return a copy of an expression. + Expression* + copy() + { return this->do_copy(); } + + // Return whether the expression is addressable--something which may + // be used as the operand of the unary & operator. + bool + is_addressable() const + { return this->do_is_addressable(); } + + // Note that we are taking the address of this expression. ESCAPES + // is true if this address escapes the current function. + void + address_taken(bool escapes) + { this->do_address_taken(escapes); } + + // Return whether this expression must be evaluated in order + // according to the order of evaluation rules. This is basically + // true of all expressions with side-effects. + bool + must_eval_in_order() const + { return this->do_must_eval_in_order(); } + + // Return the tree for this expression. + tree + get_tree(Translate_context*); + + // Return a tree handling any conversions which must be done during + // assignment. + static tree + convert_for_assignment(Translate_context*, Type* lhs_type, Type* rhs_type, + tree rhs_tree, source_location location); + + // Return a tree converting a value of one interface type to another + // interface type. If FOR_TYPE_GUARD is true this is for a type + // assertion. + static tree + convert_interface_to_interface(Translate_context*, Type* lhs_type, + Type* rhs_type, tree rhs_tree, + bool for_type_guard, source_location); + + // Return a tree implementing the comparison LHS_TREE OP RHS_TREE. + // TYPE is the type of both sides. + static tree + comparison_tree(Translate_context*, Operator op, Type* left_type, + tree left_tree, Type* right_type, tree right_tree, + source_location); + + // Return a tree for the multi-precision integer VAL in TYPE. + static tree + integer_constant_tree(mpz_t val, tree type); + + // Return a tree for the floating point value VAL in TYPE. + static tree + float_constant_tree(mpfr_t val, tree type); + + // Return a tree for the complex value REAL/IMAG in TYPE. + static tree + complex_constant_tree(mpfr_t real, mpfr_t imag, tree type); + + // Export the expression. This is only used for constants. It will + // be used for things like values of named constants and sizes of + // arrays. + void + export_expression(Export* exp) const + { this->do_export(exp); } + + // Import an expression. + static Expression* + import_expression(Import*); + + // Return a tree which checks that VAL, of arbitrary integer type, + // is non-negative and is not more than the maximum value of + // BOUND_TYPE. If SOFAR is not NULL, it is or'red into the result. + // The return value may be NULL if SOFAR is NULL. + static tree + check_bounds(tree val, tree bound_type, tree sofar, source_location); + + protected: + // May be implemented by child class: traverse the expressions. + virtual int + do_traverse(Traverse*); + + // Return a lowered expression. + virtual Expression* + do_lower(Gogo*, Named_object*, int) + { return this; } + + // Return whether this is a constant expression. + virtual bool + do_is_constant() const + { return false; } + + // Return whether this is a constant expression of integral type, + // and set VAL to the value. + virtual bool + do_integer_constant_value(bool, mpz_t, Type**) const + { return false; } + + // Return whether this is a constant expression of floating point + // type, and set VAL to the value. + virtual bool + do_float_constant_value(mpfr_t, Type**) const + { return false; } + + // Return whether this is a constant expression of complex type, and + // set REAL and IMAGE to the value. + virtual bool + do_complex_constant_value(mpfr_t, mpfr_t, Type**) const + { return false; } + + // Return whether this is a constant expression of string type, and + // set VAL to the value. + virtual bool + do_string_constant_value(std::string*) const + { return false; } + + // Called by the parser if the value is being discarded. + virtual void + do_discarding_value(); + + // Child class holds type. + virtual Type* + do_type() = 0; + + // Child class implements determining type information. + virtual void + do_determine_type(const Type_context*) = 0; + + // Child class implements type checking if needed. + virtual void + do_check_types(Gogo*) + { } + + // Child class implements copying. + virtual Expression* + do_copy() = 0; + + // Child class implements whether the expression is addressable. + virtual bool + do_is_addressable() const + { return false; } + + // Child class implements taking the address of an expression. + virtual void + do_address_taken(bool) + { } + + // Child class implements whether this expression must be evaluated + // in order. + virtual bool + do_must_eval_in_order() const + { return false; } + + // Child class implements conversion to tree. + virtual tree + do_get_tree(Translate_context*) = 0; + + // Child class implements export. + virtual void + do_export(Export*) const; + + // For children to call to warn about an unused value. + void + warn_about_unused_value(); + + // For children to call when they detect that they are in error. + void + set_is_error(); + + // For children to call to report an error conveniently. + void + report_error(const char*); + + private: + // Convert to the desired statement classification, or return NULL. + // This is a controlled dynamic cast. + template<typename Expression_class, + Expression_classification expr_classification> + Expression_class* + convert() + { + return (this->classification_ == expr_classification + ? static_cast<Expression_class*>(this) + : NULL); + } + + template<typename Expression_class, + Expression_classification expr_classification> + const Expression_class* + convert() const + { + return (this->classification_ == expr_classification + ? static_cast<const Expression_class*>(this) + : NULL); + } + + static tree + convert_type_to_interface(Translate_context*, Type*, Type*, tree, + source_location); + + static tree + get_interface_type_descriptor(Translate_context*, Type*, tree, + source_location); + + static tree + convert_interface_to_type(Translate_context*, Type*, Type*, tree, + source_location); + + // The expression classification. + Expression_classification classification_; + // The location in the input file. + source_location location_; +}; + +// A list of Expressions. + +class Expression_list +{ + public: + Expression_list() + : entries_() + { } + + // Return whether the list is empty. + bool + empty() const + { return this->entries_.empty(); } + + // Return the number of entries in the list. + size_t + size() const + { return this->entries_.size(); } + + // Add an entry to the end of the list. + void + push_back(Expression* expr) + { this->entries_.push_back(expr); } + + void + append(Expression_list* add) + { this->entries_.insert(this->entries_.end(), add->begin(), add->end()); } + + // Reserve space in the list. + void + reserve(size_t size) + { this->entries_.reserve(size); } + + // Traverse the expressions in the list. + int + traverse(Traverse*); + + // Copy the list. + Expression_list* + copy(); + + // Return true if the list contains an error expression. + bool + contains_error() const; + + // Return the first and last elements. + Expression*& + front() + { return this->entries_.front(); } + + Expression* + front() const + { return this->entries_.front(); } + + Expression*& + back() + { return this->entries_.back(); } + + Expression* + back() const + { return this->entries_.back(); } + + // Iterators. + + typedef std::vector<Expression*>::iterator iterator; + typedef std::vector<Expression*>::const_iterator const_iterator; + + iterator + begin() + { return this->entries_.begin(); } + + const_iterator + begin() const + { return this->entries_.begin(); } + + iterator + end() + { return this->entries_.end(); } + + const_iterator + end() const + { return this->entries_.end(); } + + // Erase an entry. + void + erase(iterator p) + { this->entries_.erase(p); } + + private: + std::vector<Expression*> entries_; +}; + +// An abstract base class for an expression which is only used by the +// parser, and is lowered in the lowering pass. + +class Parser_expression : public Expression +{ + public: + Parser_expression(Expression_classification classification, + source_location location) + : Expression(classification, location) + { } + + protected: + virtual Expression* + do_lower(Gogo*, Named_object*, int) = 0; + + Type* + do_type(); + + void + do_determine_type(const Type_context*) + { gcc_unreachable(); } + + void + do_check_types(Gogo*) + { gcc_unreachable(); } + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } +}; + +// An expression which is simply a variable. + +class Var_expression : public Expression +{ + public: + Var_expression(Named_object* variable, source_location location) + : Expression(EXPRESSION_VAR_REFERENCE, location), + variable_(variable) + { } + + // Return the variable. + Named_object* + named_object() const + { return this->variable_; } + + protected: + Expression* + do_lower(Gogo*, Named_object*, int); + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + Expression* + do_copy() + { return this; } + + bool + do_is_addressable() const + { return true; } + + void + do_address_taken(bool); + + tree + do_get_tree(Translate_context*); + + private: + // The variable we are referencing. + Named_object* variable_; +}; + +// A reference to a temporary variable. + +class Temporary_reference_expression : public Expression +{ + public: + Temporary_reference_expression(Temporary_statement* statement, + source_location location) + : Expression(EXPRESSION_TEMPORARY_REFERENCE, location), + statement_(statement) + { } + + protected: + Type* + do_type(); + + void + do_determine_type(const Type_context*) + { } + + Expression* + do_copy() + { return make_temporary_reference(this->statement_, this->location()); } + + bool + do_is_addressable() const + { return true; } + + void + do_address_taken(bool); + + tree + do_get_tree(Translate_context*); + + private: + // The statement where the temporary variable is defined. + Temporary_statement* statement_; +}; + +// A string expression. + +class String_expression : public Expression +{ + public: + String_expression(const std::string& val, source_location location) + : Expression(EXPRESSION_STRING, location), + val_(val), type_(NULL) + { } + + const std::string& + val() const + { return this->val_; } + + static Expression* + do_import(Import*); + + protected: + bool + do_is_constant() const + { return true; } + + bool + do_string_constant_value(std::string* val) const + { + *val = this->val_; + return true; + } + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + Expression* + do_copy() + { return this; } + + tree + do_get_tree(Translate_context*); + + void + do_export(Export*) const; + + private: + // The string value. This is immutable. + const std::string val_; + // The type as determined by context. + Type* type_; +}; + +// A binary expression. + +class Binary_expression : public Expression +{ + public: + Binary_expression(Operator op, Expression* left, Expression* right, + source_location location) + : Expression(EXPRESSION_BINARY, location), + op_(op), left_(left), right_(right) + { } + + // Return the operator. + Operator + op() + { return this->op_; } + + // Return the left hand expression. + Expression* + left() + { return this->left_; } + + // Return the right hand expression. + Expression* + right() + { return this->right_; } + + // Apply binary opcode OP to LEFT_VAL and RIGHT_VAL, setting VAL. + // LEFT_TYPE is the type of LEFT_VAL, RIGHT_TYPE is the type of + // RIGHT_VAL; LEFT_TYPE and/or RIGHT_TYPE may be NULL. Return true + // if this could be done, false if not. + static bool + eval_integer(Operator op, Type* left_type, mpz_t left_val, + Type* right_type, mpz_t right_val, source_location, + mpz_t val); + + // Apply binary opcode OP to LEFT_VAL and RIGHT_VAL, setting VAL. + // Return true if this could be done, false if not. + static bool + eval_float(Operator op, Type* left_type, mpfr_t left_val, + Type* right_type, mpfr_t right_val, mpfr_t val, + source_location); + + // Apply binary opcode OP to LEFT_REAL/LEFT_IMAG and + // RIGHT_REAL/RIGHT_IMAG, setting REAL/IMAG. Return true if this + // could be done, false if not. + static bool + eval_complex(Operator op, Type* left_type, mpfr_t left_real, + mpfr_t left_imag, Type* right_type, mpfr_t right_real, + mpfr_t right_imag, mpfr_t real, mpfr_t imag, source_location); + + // Compare integer constants according to OP. + static bool + compare_integer(Operator op, mpz_t left_val, mpz_t right_val); + + // Compare floating point constants according to OP. + static bool + compare_float(Operator op, Type* type, mpfr_t left_val, mpfr_t right_val); + + // Compare complex constants according to OP. + static bool + compare_complex(Operator op, Type* type, mpfr_t left_real, mpfr_t left_imag, + mpfr_t right_val, mpfr_t right_imag); + + static Expression* + do_import(Import*); + + // Report an error if OP can not be applied to TYPE. Return whether + // it can. + static bool + check_operator_type(Operator op, Type* type, source_location); + + protected: + int + do_traverse(Traverse* traverse); + + Expression* + do_lower(Gogo*, Named_object*, int); + + bool + do_is_constant() const + { return this->left_->is_constant() && this->right_->is_constant(); } + + bool + do_integer_constant_value(bool, mpz_t val, Type**) const; + + bool + do_float_constant_value(mpfr_t val, Type**) const; + + bool + do_complex_constant_value(mpfr_t real, mpfr_t imag, Type**) const; + + void + do_discarding_value(); + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return Expression::make_binary(this->op_, this->left_->copy(), + this->right_->copy(), this->location()); + } + + tree + do_get_tree(Translate_context*); + + void + do_export(Export*) const; + + private: + // The binary operator to apply. + Operator op_; + // The left hand side operand. + Expression* left_; + // The right hand side operand. + Expression* right_; +}; + +// A call expression. The go statement needs to dig inside this. + +class Call_expression : public Expression +{ + public: + Call_expression(Expression* fn, Expression_list* args, bool is_varargs, + source_location location) + : Expression(EXPRESSION_CALL, location), + fn_(fn), args_(args), type_(NULL), tree_(NULL), is_varargs_(is_varargs), + varargs_are_lowered_(false), types_are_determined_(false), + is_deferred_(false) + { } + + // The function to call. + Expression* + fn() const + { return this->fn_; } + + // The arguments. + Expression_list* + args() + { return this->args_; } + + const Expression_list* + args() const + { return this->args_; } + + // Get the function type. + Function_type* + get_function_type() const; + + // Return the number of values this call will return. + size_t + result_count() const; + + // Return whether this is a call to the predeclared function + // recover. + bool + is_recover_call() const; + + // Set the argument for a call to recover. + void + set_recover_arg(Expression*); + + // Whether the last argument is a varargs argument (f(a...)). + bool + is_varargs() const + { return this->is_varargs_; } + + // Whether this call is being deferred. + bool + is_deferred() const + { return this->is_deferred_; } + + // Note that the call is being deferred. + void + set_is_deferred() + { this->is_deferred_ = true; } + + protected: + int + do_traverse(Traverse*); + + virtual Expression* + do_lower(Gogo*, Named_object*, int); + + void + do_discarding_value() + { } + + virtual Type* + do_type(); + + virtual void + do_determine_type(const Type_context*); + + virtual void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return Expression::make_call(this->fn_->copy(), + (this->args_ == NULL + ? NULL + : this->args_->copy()), + this->is_varargs_, this->location()); + } + + bool + do_must_eval_in_order() const; + + virtual tree + do_get_tree(Translate_context*); + + virtual bool + do_is_recover_call() const; + + virtual void + do_set_recover_arg(Expression*); + + // Let a builtin expression change the argument list. + void + set_args(Expression_list* args) + { this->args_ = args; } + + // Let a builtin expression lower varargs. + Expression* + lower_varargs(Gogo*, Named_object* function, Type* varargs_type, + size_t param_count); + + // Let a builtin expression check whether types have been + // determined. + bool + determining_types(); + + private: + bool + check_argument_type(int, const Type*, const Type*, source_location, bool); + + tree + bound_method_function(Translate_context*, Bound_method_expression*, tree*); + + tree + interface_method_function(Translate_context*, + Interface_field_reference_expression*, + tree*); + + // The function to call. + Expression* fn_; + // The arguments to pass. This may be NULL if there are no + // arguments. + Expression_list* args_; + // The type of the expression, to avoid recomputing it. + Type* type_; + // The tree for the call, used for a call which returns a tuple. + tree tree_; + // True if the last argument is a varargs argument (f(a...)). + bool is_varargs_; + // True if varargs have already been lowered. + bool varargs_are_lowered_; + // True if types have been determined. + bool types_are_determined_; + // True if the call is an argument to a defer statement. + bool is_deferred_; +}; + +// An expression which represents a pointer to a function. + +class Func_expression : public Expression +{ + public: + Func_expression(Named_object* function, Expression* closure, + source_location location) + : Expression(EXPRESSION_FUNC_REFERENCE, location), + function_(function), closure_(closure) + { } + + // Return the object associated with the function. + const Named_object* + named_object() const + { return this->function_; } + + // Return the closure for this function. This will return NULL if + // the function has no closure, which is the normal case. + Expression* + closure() + { return this->closure_; } + + // Return a tree for this function without evaluating the closure. + tree + get_tree_without_closure(Gogo*); + + protected: + int + do_traverse(Traverse*); + + Type* + do_type(); + + void + do_determine_type(const Type_context*) + { + if (this->closure_ != NULL) + this->closure_->determine_type_no_context(); + } + + Expression* + do_copy() + { + return Expression::make_func_reference(this->function_, + (this->closure_ == NULL + ? NULL + : this->closure_->copy()), + this->location()); + } + + tree + do_get_tree(Translate_context*); + + private: + // The function itself. + Named_object* function_; + // A closure. This is normally NULL. For a nested function, it may + // be a heap-allocated struct holding pointers to all the variables + // referenced by this function and defined in enclosing functions. + Expression* closure_; +}; + +// A reference to an unknown name. + +class Unknown_expression : public Parser_expression +{ + public: + Unknown_expression(Named_object* named_object, source_location location) + : Parser_expression(EXPRESSION_UNKNOWN_REFERENCE, location), + named_object_(named_object), is_composite_literal_key_(false) + { } + + // The associated named object. + Named_object* + named_object() const + { return this->named_object_; } + + // The name of the identifier which was unknown. + const std::string& + name() const; + + // Note that this expression is being used as the key in a composite + // literal, so it may be OK if it is not resolved. + void + set_is_composite_literal_key() + { this->is_composite_literal_key_ = true; } + + // Note that this expression should no longer be treated as a + // composite literal key. + void + clear_is_composite_literal_key() + { this->is_composite_literal_key_ = false; } + + protected: + Expression* + do_lower(Gogo*, Named_object*, int); + + Expression* + do_copy() + { return new Unknown_expression(this->named_object_, this->location()); } + + private: + // The unknown name. + Named_object* named_object_; + // True if this is the key in a composite literal. + bool is_composite_literal_key_; +}; + +// An index expression. This is lowered to an array index, a string +// index, or a map index. + +class Index_expression : public Parser_expression +{ + public: + Index_expression(Expression* left, Expression* start, Expression* end, + source_location location) + : Parser_expression(EXPRESSION_INDEX, location), + left_(left), start_(start), end_(end), is_lvalue_(false) + { } + + // Record that this expression is an lvalue. + void + set_is_lvalue() + { this->is_lvalue_ = true; } + + protected: + int + do_traverse(Traverse*); + + Expression* + do_lower(Gogo*, Named_object*, int); + + Expression* + do_copy() + { + return new Index_expression(this->left_->copy(), this->start_->copy(), + (this->end_ == NULL + ? NULL + : this->end_->copy()), + this->location()); + } + + private: + // The expression being indexed. + Expression* left_; + // The first index. + Expression* start_; + // The second index. This is NULL for an index, non-NULL for a + // slice. + Expression* end_; + // Whether this is being used as an l-value. We set this during the + // parse because map index expressions need to know. + bool is_lvalue_; +}; + +// An index into a map. + +class Map_index_expression : public Expression +{ + public: + Map_index_expression(Expression* map, Expression* index, + source_location location) + : Expression(EXPRESSION_MAP_INDEX, location), + map_(map), index_(index), is_lvalue_(false), + is_in_tuple_assignment_(false) + { } + + // Return the map. + Expression* + map() + { return this->map_; } + + const Expression* + map() const + { return this->map_; } + + // Return the index. + Expression* + index() + { return this->index_; } + + const Expression* + index() const + { return this->index_; } + + // Get the type of the map being indexed. + Map_type* + get_map_type() const; + + // Record that this map expression is an lvalue. The difference is + // that an lvalue always inserts the key. + void + set_is_lvalue() + { this->is_lvalue_ = true; } + + // Return whether this map expression occurs in an assignment to a + // pair of values. + bool + is_in_tuple_assignment() const + { return this->is_in_tuple_assignment_; } + + // Record that this map expression occurs in an assignment to a pair + // of values. + void + set_is_in_tuple_assignment() + { this->is_in_tuple_assignment_ = true; } + + // Return a tree for the map index. This returns a tree which + // evaluates to a pointer to a value in the map. If INSERT is true, + // the key will be inserted if not present, and the value pointer + // will be zero initialized. If INSERT is false, and the key is not + // present in the map, the pointer will be NULL. + tree + get_value_pointer(Translate_context*, bool insert); + + protected: + int + do_traverse(Traverse*); + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return Expression::make_map_index(this->map_->copy(), + this->index_->copy(), + this->location()); + } + + // A map index expression is an lvalue but it is not addressable. + + tree + do_get_tree(Translate_context*); + + private: + // The map we are looking into. + Expression* map_; + // The index. + Expression* index_; + // Whether this is an lvalue. + bool is_lvalue_; + // Whether this is in a tuple assignment to a pair of values. + bool is_in_tuple_assignment_; +}; + +// An expression which represents a method bound to its first +// argument. + +class Bound_method_expression : public Expression +{ + public: + Bound_method_expression(Expression* expr, Expression* method, + source_location location) + : Expression(EXPRESSION_BOUND_METHOD, location), + expr_(expr), expr_type_(NULL), method_(method) + { } + + // Return the object which is the first argument. + Expression* + first_argument() + { return this->expr_; } + + // Return the implicit type of the first argument. This will be + // non-NULL when using a method from an anonymous field without + // using an explicit stub. + Type* + first_argument_type() const + { return this->expr_type_; } + + // Return the reference to the method function. + Expression* + method() + { return this->method_; } + + // Set the implicit type of the expression. + void + set_first_argument_type(Type* type) + { this->expr_type_ = type; } + + protected: + int + do_traverse(Traverse*); + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return new Bound_method_expression(this->expr_->copy(), + this->method_->copy(), + this->location()); + } + + tree + do_get_tree(Translate_context*); + + private: + // The object used to find the method. This is passed to the method + // as the first argument. + Expression* expr_; + // The implicit type of the object to pass to the method. This is + // NULL in the normal case, non-NULL when using a method from an + // anonymous field which does not require a stub. + Type* expr_type_; + // The method itself. This is a Func_expression. + Expression* method_; +}; + +// A reference to a field in a struct. + +class Field_reference_expression : public Expression +{ + public: + Field_reference_expression(Expression* expr, unsigned int field_index, + source_location location) + : Expression(EXPRESSION_FIELD_REFERENCE, location), + expr_(expr), field_index_(field_index) + { } + + // Return the struct expression. + Expression* + expr() const + { return this->expr_; } + + // Return the field index. + unsigned int + field_index() const + { return this->field_index_; } + + // Set the struct expression. This is used when parsing. + void + set_struct_expression(Expression* expr) + { + gcc_assert(this->expr_ == NULL); + this->expr_ = expr; + } + + protected: + int + do_traverse(Traverse* traverse) + { return Expression::traverse(&this->expr_, traverse); } + + Type* + do_type(); + + void + do_determine_type(const Type_context*) + { this->expr_->determine_type_no_context(); } + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return Expression::make_field_reference(this->expr_->copy(), + this->field_index_, + this->location()); + } + + bool + do_is_addressable() const + { return this->expr_->is_addressable(); } + + tree + do_get_tree(Translate_context*); + + private: + // The expression we are looking into. This should have a type of + // struct. + Expression* expr_; + // The zero-based index of the field we are retrieving. + unsigned int field_index_; +}; + +// A reference to a field of an interface. + +class Interface_field_reference_expression : public Expression +{ + public: + Interface_field_reference_expression(Expression* expr, + const std::string& name, + source_location location) + : Expression(EXPRESSION_INTERFACE_FIELD_REFERENCE, location), + expr_(expr), name_(name) + { } + + // Return the expression for the interface object. + Expression* + expr() + { return this->expr_; } + + // Return the name of the method to call. + const std::string& + name() const + { return this->name_; } + + // Return a tree for the pointer to the function to call, given a + // tree for the expression. + tree + get_function_tree(Translate_context*, tree); + + // Return a tree for the first argument to pass to the interface + // function, given a tree for the expression. This is the real + // object associated with the interface object. + tree + get_underlying_object_tree(Translate_context*, tree); + + protected: + int + do_traverse(Traverse* traverse); + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return Expression::make_interface_field_reference(this->expr_->copy(), + this->name_, + this->location()); + } + + tree + do_get_tree(Translate_context*); + + private: + // The expression for the interface object. This should have a type + // of interface or pointer to interface. + Expression* expr_; + // The field we are retrieving--the name of the method. + std::string name_; +}; + +// A type guard expression. + +class Type_guard_expression : public Expression +{ + public: + Type_guard_expression(Expression* expr, Type* type, source_location location) + : Expression(EXPRESSION_TYPE_GUARD, location), + expr_(expr), type_(type) + { } + + // Return the expression to convert. + Expression* + expr() + { return this->expr_; } + + // Return the type to which to convert. + Type* + type() + { return this->type_; } + + protected: + int + do_traverse(Traverse* traverse); + + Type* + do_type() + { return this->type_; } + + void + do_determine_type(const Type_context*) + { this->expr_->determine_type_no_context(); } + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return new Type_guard_expression(this->expr_->copy(), this->type_, + this->location()); + } + + tree + do_get_tree(Translate_context*); + + private: + // The expression to convert. + Expression* expr_; + // The type to which to convert. + Type* type_; +}; + +// A receive expression. + +class Receive_expression : public Expression +{ + public: + Receive_expression(Expression* channel, source_location location) + : Expression(EXPRESSION_RECEIVE, location), + channel_(channel), is_value_discarded_(false), for_select_(false) + { } + + // Return the channel. + Expression* + channel() + { return this->channel_; } + + // Note that this is for a select statement. + void + set_for_select() + { this->for_select_ = true; } + + protected: + int + do_traverse(Traverse* traverse) + { return Expression::traverse(&this->channel_, traverse); } + + void + do_discarding_value() + { this->is_value_discarded_ = true; } + + Type* + do_type(); + + void + do_determine_type(const Type_context*) + { this->channel_->determine_type_no_context(); } + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return Expression::make_receive(this->channel_->copy(), this->location()); + } + + bool + do_must_eval_in_order() const + { return true; } + + tree + do_get_tree(Translate_context*); + + private: + // The channel from which we are receiving. + Expression* channel_; + // Whether the value is being discarded. + bool is_value_discarded_; + // Whether this is for a select statement. + bool for_select_; +}; + +// A send expression. + +class Send_expression : public Expression +{ + public: + Send_expression(Expression* channel, Expression* val, + source_location location) + : Expression(EXPRESSION_SEND, location), + channel_(channel), val_(val), is_value_discarded_(false), + for_select_(false) + { } + + // Note that this is for a select statement. + void + set_for_select() + { this->for_select_ = true; } + + protected: + int + do_traverse(Traverse* traverse); + + void + do_discarding_value() + { this->is_value_discarded_ = true; } + + Type* + do_type(); + + void + do_determine_type(const Type_context*); + + void + do_check_types(Gogo*); + + Expression* + do_copy() + { + return Expression::make_send(this->channel_->copy(), this->val_->copy(), + this->location()); + } + + bool + do_must_eval_in_order() const + { return true; } + + tree + do_get_tree(Translate_context*); + + private: + // The channel on which to send the value. + Expression* channel_; + // The value to send. + Expression* val_; + // Whether the value is being discarded. + bool is_value_discarded_; + // Whether this is for a select statement. + bool for_select_; +}; + +#endif // !defined(GO_EXPRESSIONS_H) diff --git a/gcc/go/gofrontend/go-dump.cc b/gcc/go/gofrontend/go-dump.cc new file mode 100644 index 000000000..dd5a4c3f2 --- /dev/null +++ b/gcc/go/gofrontend/go-dump.cc @@ -0,0 +1,53 @@ +// go-dump.cc -- Go frontend debug dumps. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include "go-c.h" +#include "go-dump.h" + +namespace { + +// The list of dumps. + +Go_dump* dumps; + +} // End empty namespace. + +// Create a new dump. + +Go_dump::Go_dump(const char* name) + : next_(dumps), name_(name), is_enabled_(false) +{ + dumps = this; +} + +// Enable a dump by name. + +bool +Go_dump::enable_by_name(const char* name) +{ + bool is_all = strcmp(name, "all") == 0; + bool found = false; + for (Go_dump* p = dumps; p != NULL; p = p->next_) + { + if (is_all || strcmp(name, p->name_) == 0) + { + p->is_enabled_ = true; + found = true; + } + } + return found; +} + +// Enable a dump. Return 1 if this is a real name, 0 if not. + +GO_EXTERN_C +int +go_enable_dump(const char* name) +{ + return Go_dump::enable_by_name(name) ? 1 : 0; +} diff --git a/gcc/go/gofrontend/go-dump.h b/gcc/go/gofrontend/go-dump.h new file mode 100644 index 000000000..13639bc12 --- /dev/null +++ b/gcc/go/gofrontend/go-dump.h @@ -0,0 +1,38 @@ +// go-dump.h -- Go frontend debug dumps. -*- C++ -*- + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef GO_DUMP_H +#define GO_DUMP_H + +// This class manages different arguments to -fgo-dump-XXX. If you +// want to create a new dump, create a variable of this type with the +// name to use for XXX. You can then use is_enabled to see whether +// the -fgo-dump-XXX option was used on the command line. + +class Go_dump +{ + public: + Go_dump(const char* name); + + // Whether this dump was enabled. + bool + is_enabled() const + { return this->is_enabled_; } + + // Enable a dump by name. Return true if the dump was found. + static bool + enable_by_name(const char*); + + private: + // The next dump. These are not in any order. + Go_dump* next_; + // The name of this dump. + const char* name_; + // Whether this dump was enabled. + bool is_enabled_; +}; + +#endif // !defined(GO_DUMP_H) diff --git a/gcc/go/gofrontend/go.cc b/gcc/go/gofrontend/go.cc new file mode 100644 index 000000000..7b1fd7ecc --- /dev/null +++ b/gcc/go/gofrontend/go.cc @@ -0,0 +1,150 @@ +// go.cc -- Go frontend main file for gcc. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include "go-c.h" + +#include "lex.h" +#include "parse.h" +#include "gogo.h" + +// The unique prefix to use for exported symbols. This is set during +// option processing. + +static std::string unique_prefix; + +// The data structures we build to represent the file. +static Gogo* gogo; + +// Create the main IR data structure. + +GO_EXTERN_C +void +go_create_gogo(int int_type_size, int pointer_size) +{ + gcc_assert(::gogo == NULL); + ::gogo = new Gogo(int_type_size, pointer_size); + if (!unique_prefix.empty()) + ::gogo->set_unique_prefix(unique_prefix); +} + +// Set the unique prefix we use for exported symbols. + +GO_EXTERN_C +void +go_set_prefix(const char* arg) +{ + unique_prefix = arg; + for (size_t i = 0; i < unique_prefix.length(); ++i) + { + char c = unique_prefix[i]; + if ((c >= 'a' && c <= 'z') + || (c >= 'A' && c <= 'Z') + || (c >= '0' && c <= '9') + || c == '_') + ; + else + unique_prefix[i] = '_'; + } +} + +// Parse the input files. + +GO_EXTERN_C +void +go_parse_input_files(const char** filenames, unsigned int filename_count, + bool only_check_syntax, bool require_return_statement) +{ + gcc_assert(filename_count > 0); + for (unsigned int i = 0; i < filename_count; ++i) + { + if (i > 0) + ::gogo->clear_file_scope(); + + const char* filename = filenames[i]; + FILE* file; + if (strcmp(filename, "-") == 0) + file = stdin; + else + { + file = fopen(filename, "r"); + if (file == NULL) + fatal_error("cannot open %s: %m", filename); + } + + Lex lexer(filename, file); + + Parse parse(&lexer, ::gogo); + parse.program(); + + if (strcmp(filename, "-") != 0) + fclose(file); + } + + ::gogo->clear_file_scope(); + + // If the global predeclared names are referenced but not defined, + // define them now. + ::gogo->define_global_names(); + + // Finalize method lists and build stub methods for named types. + ::gogo->finalize_methods(); + + // Now that we have seen all the names, lower the parse tree into a + // form which is easier to use. + ::gogo->lower_parse_tree(); + + // Now that we have seen all the names, verify that types are + // correct. + ::gogo->verify_types(); + + // Work out types of unspecified constants and variables. + ::gogo->determine_types(); + + // Check types and issue errors as appropriate. + ::gogo->check_types(); + + if (only_check_syntax) + return; + + // Check that functions have return statements. + if (require_return_statement) + ::gogo->check_return_statements(); + + // Export global identifiers as appropriate. + ::gogo->do_exports(); + + // Turn short-cut operators (&&, ||) into explicit if statements. + ::gogo->remove_shortcuts(); + + // Use temporary variables to force order of evaluation. + ::gogo->order_evaluations(); + + // Build thunks for functions which call recover. + ::gogo->build_recover_thunks(); + + // Convert complicated go and defer statements into simpler ones. + ::gogo->simplify_thunk_statements(); +} + +// Write out globals. + +GO_EXTERN_C +void +go_write_globals() +{ + return ::gogo->write_globals(); +} + +// Return the global IR structure. This is used by some of the +// langhooks to pass to other code. + +Gogo* +go_get_gogo() +{ + return ::gogo; +} diff --git a/gcc/go/gofrontend/gogo-tree.cc b/gcc/go/gofrontend/gogo-tree.cc new file mode 100644 index 000000000..562a5afa9 --- /dev/null +++ b/gcc/go/gofrontend/gogo-tree.cc @@ -0,0 +1,3145 @@ +// gogo-tree.cc -- convert Go frontend Gogo IR to gcc trees. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include <gmp.h> + +#ifndef ENABLE_BUILD_WITH_CXX +extern "C" +{ +#endif + +#include "toplev.h" +#include "tree.h" +#include "gimple.h" +#include "tree-iterator.h" +#include "cgraph.h" +#include "langhooks.h" +#include "convert.h" +#include "output.h" +#include "diagnostic.h" + +#ifndef ENABLE_BUILD_WITH_CXX +} +#endif + +#include "go-c.h" +#include "types.h" +#include "expressions.h" +#include "statements.h" +#include "gogo.h" + +// Whether we have seen any errors. + +bool +saw_errors() +{ + return errorcount != 0 || sorrycount != 0; +} + +// A helper function. + +static inline tree +get_identifier_from_string(const std::string& str) +{ + return get_identifier_with_length(str.data(), str.length()); +} + +// Builtin functions. + +static std::map<std::string, tree> builtin_functions; + +// Define a builtin function. BCODE is the builtin function code +// defined by builtins.def. NAME is the name of the builtin function. +// LIBNAME is the name of the corresponding library function, and is +// NULL if there isn't one. FNTYPE is the type of the function. +// CONST_P is true if the function has the const attribute. + +static void +define_builtin(built_in_function bcode, const char* name, const char* libname, + tree fntype, bool const_p) +{ + tree decl = add_builtin_function(name, fntype, bcode, BUILT_IN_NORMAL, + libname, NULL_TREE); + if (const_p) + TREE_READONLY(decl) = 1; + built_in_decls[bcode] = decl; + implicit_built_in_decls[bcode] = decl; + builtin_functions[name] = decl; + if (libname != NULL) + { + decl = add_builtin_function(libname, fntype, bcode, BUILT_IN_NORMAL, + NULL, NULL_TREE); + if (const_p) + TREE_READONLY(decl) = 1; + builtin_functions[libname] = decl; + } +} + +// Create trees for implicit builtin functions. + +void +Gogo::define_builtin_function_trees() +{ + /* We need to define the fetch_and_add functions, since we use them + for ++ and --. */ + tree t = go_type_for_size(BITS_PER_UNIT, 1); + tree p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE)); + define_builtin(BUILT_IN_ADD_AND_FETCH_1, "__sync_fetch_and_add_1", NULL, + build_function_type_list(t, p, t, NULL_TREE), false); + + t = go_type_for_size(BITS_PER_UNIT * 2, 1); + p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE)); + define_builtin (BUILT_IN_ADD_AND_FETCH_2, "__sync_fetch_and_add_2", NULL, + build_function_type_list(t, p, t, NULL_TREE), false); + + t = go_type_for_size(BITS_PER_UNIT * 4, 1); + p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE)); + define_builtin(BUILT_IN_ADD_AND_FETCH_4, "__sync_fetch_and_add_4", NULL, + build_function_type_list(t, p, t, NULL_TREE), false); + + t = go_type_for_size(BITS_PER_UNIT * 8, 1); + p = build_pointer_type(build_qualified_type(t, TYPE_QUAL_VOLATILE)); + define_builtin(BUILT_IN_ADD_AND_FETCH_8, "__sync_fetch_and_add_8", NULL, + build_function_type_list(t, p, t, NULL_TREE), false); + + // We use __builtin_expect for magic import functions. + define_builtin(BUILT_IN_EXPECT, "__builtin_expect", NULL, + build_function_type_list(long_integer_type_node, + long_integer_type_node, + long_integer_type_node, + NULL_TREE), + true); + + // We use __builtin_memmove for the predeclared copy function. + define_builtin(BUILT_IN_MEMMOVE, "__builtin_memmove", "memmove", + build_function_type_list(ptr_type_node, + ptr_type_node, + const_ptr_type_node, + size_type_node, + NULL_TREE), + false); + + // We provide sqrt for the math library. + define_builtin(BUILT_IN_SQRT, "__builtin_sqrt", "sqrt", + build_function_type_list(double_type_node, + double_type_node, + NULL_TREE), + true); + define_builtin(BUILT_IN_SQRTL, "__builtin_sqrtl", "sqrtl", + build_function_type_list(long_double_type_node, + long_double_type_node, + NULL_TREE), + true); + + // We use __builtin_return_address in the thunk we build for + // functions which call recover. + define_builtin(BUILT_IN_RETURN_ADDRESS, "__builtin_return_address", NULL, + build_function_type_list(ptr_type_node, + unsigned_type_node, + NULL_TREE), + false); + + // The compiler uses __builtin_trap for some exception handling + // cases. + define_builtin(BUILT_IN_TRAP, "__builtin_trap", NULL, + build_function_type(void_type_node, void_list_node), + false); +} + +// Get the name to use for the import control function. If there is a +// global function or variable, then we know that that name must be +// unique in the link, and we use it as the basis for our name. + +const std::string& +Gogo::get_init_fn_name() +{ + if (this->init_fn_name_.empty()) + { + gcc_assert(this->package_ != NULL); + if (this->is_main_package()) + { + // Use a name which the runtime knows. + this->init_fn_name_ = "__go_init_main"; + } + else + { + std::string s = this->unique_prefix(); + s.append(1, '.'); + s.append(this->package_name()); + s.append("..import"); + this->init_fn_name_ = s; + } + } + + return this->init_fn_name_; +} + +// Add statements to INIT_STMT_LIST which run the initialization +// functions for imported packages. This is only used for the "main" +// package. + +void +Gogo::init_imports(tree* init_stmt_list) +{ + gcc_assert(this->is_main_package()); + + if (this->imported_init_fns_.empty()) + return; + + tree fntype = build_function_type(void_type_node, void_list_node); + + // We must call them in increasing priority order. + std::vector<Import_init> v; + for (std::set<Import_init>::const_iterator p = + this->imported_init_fns_.begin(); + p != this->imported_init_fns_.end(); + ++p) + v.push_back(*p); + std::sort(v.begin(), v.end()); + + for (std::vector<Import_init>::const_iterator p = v.begin(); + p != v.end(); + ++p) + { + std::string user_name = p->package_name() + ".init"; + tree decl = build_decl(UNKNOWN_LOCATION, FUNCTION_DECL, + get_identifier_from_string(user_name), + fntype); + const std::string& init_name(p->init_name()); + SET_DECL_ASSEMBLER_NAME(decl, get_identifier_from_string(init_name)); + TREE_PUBLIC(decl) = 1; + DECL_EXTERNAL(decl) = 1; + append_to_statement_list(build_call_expr(decl, 0), init_stmt_list); + } +} + +// Register global variables with the garbage collector. We need to +// register all variables which can hold a pointer value. They become +// roots during the mark phase. We build a struct that is easy to +// hook into a list of roots. + +// struct __go_gc_root_list +// { +// struct __go_gc_root_list* __next; +// struct __go_gc_root +// { +// void* __decl; +// size_t __size; +// } __roots[]; +// }; + +// The last entry in the roots array has a NULL decl field. + +void +Gogo::register_gc_vars(const std::vector<Named_object*>& var_gc, + tree* init_stmt_list) +{ + if (var_gc.empty()) + return; + + size_t count = var_gc.size(); + + tree root_type = Gogo::builtin_struct(NULL, "__go_gc_root", NULL_TREE, 2, + "__next", + ptr_type_node, + "__size", + sizetype); + + tree index_type = build_index_type(size_int(count)); + tree array_type = build_array_type(root_type, index_type); + + tree root_list_type = make_node(RECORD_TYPE); + root_list_type = Gogo::builtin_struct(NULL, "__go_gc_root_list", + root_list_type, 2, + "__next", + build_pointer_type(root_list_type), + "__roots", + array_type); + + // Build an initialier for the __roots array. + + VEC(constructor_elt,gc)* roots_init = VEC_alloc(constructor_elt, gc, + count + 1); + + size_t i = 0; + for (std::vector<Named_object*>::const_iterator p = var_gc.begin(); + p != var_gc.end(); + ++p, ++i) + { + VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 2); + + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + tree field = TYPE_FIELDS(root_type); + elt->index = field; + tree decl = (*p)->get_tree(this, NULL); + gcc_assert(TREE_CODE(decl) == VAR_DECL); + elt->value = build_fold_addr_expr(decl); + + elt = VEC_quick_push(constructor_elt, init, NULL); + field = DECL_CHAIN(field); + elt->index = field; + elt->value = DECL_SIZE_UNIT(decl); + + elt = VEC_quick_push(constructor_elt, roots_init, NULL); + elt->index = size_int(i); + elt->value = build_constructor(root_type, init); + } + + // The list ends with a NULL entry. + + VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 2); + + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + tree field = TYPE_FIELDS(root_type); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), null_pointer_node); + + elt = VEC_quick_push(constructor_elt, init, NULL); + field = DECL_CHAIN(field); + elt->index = field; + elt->value = size_zero_node; + + elt = VEC_quick_push(constructor_elt, roots_init, NULL); + elt->index = size_int(i); + elt->value = build_constructor(root_type, init); + + // Build a constructor for the struct. + + VEC(constructor_elt,gc*) root_list_init = VEC_alloc(constructor_elt, gc, 2); + + elt = VEC_quick_push(constructor_elt, root_list_init, NULL); + field = TYPE_FIELDS(root_list_type); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), null_pointer_node); + + elt = VEC_quick_push(constructor_elt, root_list_init, NULL); + field = DECL_CHAIN(field); + elt->index = field; + elt->value = build_constructor(array_type, roots_init); + + // Build a decl to register. + + tree decl = build_decl(BUILTINS_LOCATION, VAR_DECL, + create_tmp_var_name("gc"), root_list_type); + DECL_EXTERNAL(decl) = 0; + TREE_PUBLIC(decl) = 0; + TREE_STATIC(decl) = 1; + DECL_ARTIFICIAL(decl) = 1; + DECL_INITIAL(decl) = build_constructor(root_list_type, root_list_init); + rest_of_decl_compilation(decl, 1, 0); + + static tree register_gc_fndecl; + tree call = Gogo::call_builtin(®ister_gc_fndecl, BUILTINS_LOCATION, + "__go_register_gc_roots", + 1, + void_type_node, + build_pointer_type(root_list_type), + build_fold_addr_expr(decl)); + if (call != error_mark_node) + append_to_statement_list(call, init_stmt_list); +} + +// Build the decl for the initialization function. + +tree +Gogo::initialization_function_decl() +{ + // The tedious details of building your own function. There doesn't + // seem to be a helper function for this. + std::string name = this->package_name() + ".init"; + tree fndecl = build_decl(BUILTINS_LOCATION, FUNCTION_DECL, + get_identifier_from_string(name), + build_function_type(void_type_node, + void_list_node)); + const std::string& asm_name(this->get_init_fn_name()); + SET_DECL_ASSEMBLER_NAME(fndecl, get_identifier_from_string(asm_name)); + + tree resdecl = build_decl(BUILTINS_LOCATION, RESULT_DECL, NULL_TREE, + void_type_node); + DECL_ARTIFICIAL(resdecl) = 1; + DECL_CONTEXT(resdecl) = fndecl; + DECL_RESULT(fndecl) = resdecl; + + TREE_STATIC(fndecl) = 1; + TREE_USED(fndecl) = 1; + DECL_ARTIFICIAL(fndecl) = 1; + TREE_PUBLIC(fndecl) = 1; + + DECL_INITIAL(fndecl) = make_node(BLOCK); + TREE_USED(DECL_INITIAL(fndecl)) = 1; + + return fndecl; +} + +// Create the magic initialization function. INIT_STMT_LIST is the +// code that it needs to run. + +void +Gogo::write_initialization_function(tree fndecl, tree init_stmt_list) +{ + // Make sure that we thought we needed an initialization function, + // as otherwise we will not have reported it in the export data. + gcc_assert(this->is_main_package() || this->need_init_fn_); + + if (fndecl == NULL_TREE) + fndecl = this->initialization_function_decl(); + + DECL_SAVED_TREE(fndecl) = init_stmt_list; + + current_function_decl = fndecl; + if (DECL_STRUCT_FUNCTION(fndecl) == NULL) + push_struct_function(fndecl); + else + push_cfun(DECL_STRUCT_FUNCTION(fndecl)); + cfun->function_end_locus = BUILTINS_LOCATION; + + gimplify_function_tree(fndecl); + + cgraph_add_new_function(fndecl, false); + cgraph_mark_needed_node(cgraph_node(fndecl)); + + current_function_decl = NULL_TREE; + pop_cfun(); +} + +// Search for references to VAR in any statements or called functions. + +class Find_var : public Traverse +{ + public: + // A hash table we use to avoid looping. The index is the name of a + // named object. We only look through objects defined in this + // package. + typedef Unordered_set(std::string) Seen_objects; + + Find_var(Named_object* var, Seen_objects* seen_objects) + : Traverse(traverse_expressions), + var_(var), seen_objects_(seen_objects), found_(false) + { } + + // Whether the variable was found. + bool + found() const + { return this->found_; } + + int + expression(Expression**); + + private: + // The variable we are looking for. + Named_object* var_; + // Names of objects we have already seen. + Seen_objects* seen_objects_; + // True if the variable was found. + bool found_; +}; + +// See if EXPR refers to VAR, looking through function calls and +// variable initializations. + +int +Find_var::expression(Expression** pexpr) +{ + Expression* e = *pexpr; + + Var_expression* ve = e->var_expression(); + if (ve != NULL) + { + Named_object* v = ve->named_object(); + if (v == this->var_) + { + this->found_ = true; + return TRAVERSE_EXIT; + } + + if (v->is_variable() && v->package() == NULL) + { + Expression* init = v->var_value()->init(); + if (init != NULL) + { + std::pair<Seen_objects::iterator, bool> ins = + this->seen_objects_->insert(v->name()); + if (ins.second) + { + // This is the first time we have seen this name. + if (Expression::traverse(&init, this) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + } + } + } + + // We traverse the code of any function we see. Note that this + // means that we will traverse the code of a function whose address + // is taken even if it is not called. + Func_expression* fe = e->func_expression(); + if (fe != NULL) + { + const Named_object* f = fe->named_object(); + if (f->is_function() && f->package() == NULL) + { + std::pair<Seen_objects::iterator, bool> ins = + this->seen_objects_->insert(f->name()); + if (ins.second) + { + // This is the first time we have seen this name. + if (f->func_value()->block()->traverse(this) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + } + } + + return TRAVERSE_CONTINUE; +} + +// Return true if EXPR refers to VAR. + +static bool +expression_requires(Expression* expr, Block* preinit, Named_object* var) +{ + Find_var::Seen_objects seen_objects; + Find_var find_var(var, &seen_objects); + if (expr != NULL) + Expression::traverse(&expr, &find_var); + if (preinit != NULL) + preinit->traverse(&find_var); + + return find_var.found(); +} + +// Sort variable initializations. If the initialization expression +// for variable A refers directly or indirectly to the initialization +// expression for variable B, then we must initialize B before A. + +class Var_init +{ + public: + Var_init() + : var_(NULL), init_(NULL_TREE), waiting_(0) + { } + + Var_init(Named_object* var, tree init) + : var_(var), init_(init), waiting_(0) + { } + + // Return the variable. + Named_object* + var() const + { return this->var_; } + + // Return the initialization expression. + tree + init() const + { return this->init_; } + + // Return the number of variables waiting for this one to be + // initialized. + size_t + waiting() const + { return this->waiting_; } + + // Increment the number waiting. + void + increment_waiting() + { ++this->waiting_; } + + private: + // The variable being initialized. + Named_object* var_; + // The initialization expression to run. + tree init_; + // The number of variables which are waiting for this one. + size_t waiting_; +}; + +typedef std::list<Var_init> Var_inits; + +// Sort the variable initializations. The rule we follow is that we +// emit them in the order they appear in the array, except that if the +// initialization expression for a variable V1 depends upon another +// variable V2 then we initialize V1 after V2. + +static void +sort_var_inits(Var_inits* var_inits) +{ + Var_inits ready; + while (!var_inits->empty()) + { + Var_inits::iterator p1 = var_inits->begin(); + Named_object* var = p1->var(); + Expression* init = var->var_value()->init(); + Block* preinit = var->var_value()->preinit(); + + // Start walking through the list to see which variables VAR + // needs to wait for. We can skip P1->WAITING variables--that + // is the number we've already checked. + Var_inits::iterator p2 = p1; + ++p2; + for (size_t i = p1->waiting(); i > 0; --i) + ++p2; + + for (; p2 != var_inits->end(); ++p2) + { + if (expression_requires(init, preinit, p2->var())) + { + // Check for cycles. + if (expression_requires(p2->var()->var_value()->init(), + p2->var()->var_value()->preinit(), + var)) + { + error_at(var->location(), + ("initialization expressions for %qs and " + "%qs depend upon each other"), + var->message_name().c_str(), + p2->var()->message_name().c_str()); + inform(p2->var()->location(), "%qs defined here", + p2->var()->message_name().c_str()); + p2 = var_inits->end(); + } + else + { + // We can't emit P1 until P2 is emitted. Move P1. + // Note that the WAITING loop always executes at + // least once, which is what we want. + p2->increment_waiting(); + Var_inits::iterator p3 = p2; + for (size_t i = p2->waiting(); i > 0; --i) + ++p3; + var_inits->splice(p3, *var_inits, p1); + } + break; + } + } + + if (p2 == var_inits->end()) + { + // VAR does not depends upon any other initialization expressions. + + // Check for a loop of VAR on itself. We only do this if + // INIT is not NULL; when INIT is NULL, it means that + // PREINIT sets VAR, which we will interpret as a loop. + if (init != NULL && expression_requires(init, preinit, var)) + error_at(var->location(), + "initialization expression for %qs depends upon itself", + var->message_name().c_str()); + ready.splice(ready.end(), *var_inits, p1); + } + } + + // Now READY is the list in the desired initialization order. + var_inits->swap(ready); +} + +// Write out the global definitions. + +void +Gogo::write_globals() +{ + this->convert_named_types(); + this->build_interface_method_tables(); + + Bindings* bindings = this->current_bindings(); + size_t count = bindings->size_definitions(); + + tree* vec = new tree[count]; + + tree init_fndecl = NULL_TREE; + tree init_stmt_list = NULL_TREE; + + if (this->is_main_package()) + this->init_imports(&init_stmt_list); + + // A list of variable initializations. + Var_inits var_inits; + + // A list of variables which need to be registered with the garbage + // collector. + std::vector<Named_object*> var_gc; + var_gc.reserve(count); + + tree var_init_stmt_list = NULL_TREE; + size_t i = 0; + for (Bindings::const_definitions_iterator p = bindings->begin_definitions(); + p != bindings->end_definitions(); + ++p, ++i) + { + Named_object* no = *p; + + gcc_assert(!no->is_type_declaration() && !no->is_function_declaration()); + // There is nothing to do for a package. + if (no->is_package()) + { + --i; + --count; + continue; + } + + // There is nothing to do for an object which was imported from + // a different package into the global scope. + if (no->package() != NULL) + { + --i; + --count; + continue; + } + + // There is nothing useful we can output for constants which + // have ideal or non-integeral type. + if (no->is_const()) + { + Type* type = no->const_value()->type(); + if (type == NULL) + type = no->const_value()->expr()->type(); + if (type->is_abstract() || type->integer_type() == NULL) + { + --i; + --count; + continue; + } + } + + vec[i] = no->get_tree(this, NULL); + + if (vec[i] == error_mark_node) + { + gcc_assert(saw_errors()); + --i; + --count; + continue; + } + + // If a variable is initialized to a non-constant value, do the + // initialization in an initialization function. + if (TREE_CODE(vec[i]) == VAR_DECL) + { + gcc_assert(no->is_variable()); + + // Check for a sink variable, which may be used to run + // an initializer purely for its side effects. + bool is_sink = no->name()[0] == '_' && no->name()[1] == '.'; + + tree var_init_tree = NULL_TREE; + if (!no->var_value()->has_pre_init()) + { + tree init = no->var_value()->get_init_tree(this, NULL); + if (init == error_mark_node) + gcc_assert(saw_errors()); + else if (init == NULL_TREE) + ; + else if (TREE_CONSTANT(init)) + DECL_INITIAL(vec[i]) = init; + else if (is_sink) + var_init_tree = init; + else + var_init_tree = fold_build2_loc(no->location(), MODIFY_EXPR, + void_type_node, vec[i], init); + } + else + { + // We are going to create temporary variables which + // means that we need an fndecl. + if (init_fndecl == NULL_TREE) + init_fndecl = this->initialization_function_decl(); + current_function_decl = init_fndecl; + if (DECL_STRUCT_FUNCTION(init_fndecl) == NULL) + push_struct_function(init_fndecl); + else + push_cfun(DECL_STRUCT_FUNCTION(init_fndecl)); + + tree var_decl = is_sink ? NULL_TREE : vec[i]; + var_init_tree = no->var_value()->get_init_block(this, NULL, + var_decl); + + current_function_decl = NULL_TREE; + pop_cfun(); + } + + if (var_init_tree != NULL_TREE && var_init_tree != error_mark_node) + { + if (no->var_value()->init() == NULL + && !no->var_value()->has_pre_init()) + append_to_statement_list(var_init_tree, &var_init_stmt_list); + else + var_inits.push_back(Var_init(no, var_init_tree)); + } + + if (!is_sink && no->var_value()->type()->has_pointer()) + var_gc.push_back(no); + } + } + + // Register global variables with the garbage collector. + this->register_gc_vars(var_gc, &init_stmt_list); + + // Simple variable initializations, after all variables are + // registered. + append_to_statement_list(var_init_stmt_list, &init_stmt_list); + + // Complex variable initializations, first sorting them into a + // workable order. + if (!var_inits.empty()) + { + sort_var_inits(&var_inits); + for (Var_inits::const_iterator p = var_inits.begin(); + p != var_inits.end(); + ++p) + append_to_statement_list(p->init(), &init_stmt_list); + } + + // After all the variables are initialized, call the "init" + // functions if there are any. + for (std::vector<Named_object*>::const_iterator p = + this->init_functions_.begin(); + p != this->init_functions_.end(); + ++p) + { + tree decl = (*p)->get_tree(this, NULL); + tree call = build_call_expr(decl, 0); + append_to_statement_list(call, &init_stmt_list); + } + + // Set up a magic function to do all the initialization actions. + // This will be called if this package is imported. + if (init_stmt_list != NULL_TREE + || this->need_init_fn_ + || this->is_main_package()) + this->write_initialization_function(init_fndecl, init_stmt_list); + + // Pass everything back to the middle-end. + + wrapup_global_declarations(vec, count); + + cgraph_finalize_compilation_unit(); + + check_global_declarations(vec, count); + emit_debug_global_declarations(vec, count); + + delete[] vec; +} + +// Get a tree for the identifier for a named object. + +tree +Named_object::get_id(Gogo* gogo) +{ + std::string decl_name; + if (this->is_function_declaration() + && !this->func_declaration_value()->asm_name().empty()) + decl_name = this->func_declaration_value()->asm_name(); + else if ((this->is_variable() && !this->var_value()->is_global()) + || (this->is_type() + && this->type_value()->location() == BUILTINS_LOCATION)) + { + // We don't need the package name for local variables or builtin + // types. + decl_name = Gogo::unpack_hidden_name(this->name_); + } + else + { + std::string package_name; + if (this->package_ == NULL) + package_name = gogo->package_name(); + else + package_name = this->package_->name(); + + decl_name = package_name + '.' + Gogo::unpack_hidden_name(this->name_); + + Function_type* fntype; + if (this->is_function()) + fntype = this->func_value()->type(); + else if (this->is_function_declaration()) + fntype = this->func_declaration_value()->type(); + else + fntype = NULL; + if (fntype != NULL && fntype->is_method()) + { + decl_name.push_back('.'); + decl_name.append(fntype->receiver()->type()->mangled_name(gogo)); + } + } + if (this->is_type()) + { + const Named_object* in_function = this->type_value()->in_function(); + if (in_function != NULL) + decl_name += '$' + in_function->name(); + } + return get_identifier_from_string(decl_name); +} + +// Get a tree for a named object. + +tree +Named_object::get_tree(Gogo* gogo, Named_object* function) +{ + if (this->tree_ != NULL_TREE) + { + // If this is a variable whose address is taken, we must rebuild + // the INDIRECT_REF each time to avoid invalid sharing. + tree ret = this->tree_; + if (((this->classification_ == NAMED_OBJECT_VAR + && this->var_value()->is_in_heap()) + || (this->classification_ == NAMED_OBJECT_RESULT_VAR + && this->result_var_value()->is_in_heap())) + && ret != error_mark_node) + { + gcc_assert(TREE_CODE(ret) == INDIRECT_REF); + ret = build_fold_indirect_ref(TREE_OPERAND(ret, 0)); + TREE_THIS_NOTRAP(ret) = 1; + } + return ret; + } + + tree name; + if (this->classification_ == NAMED_OBJECT_TYPE) + name = NULL_TREE; + else + name = this->get_id(gogo); + tree decl; + switch (this->classification_) + { + case NAMED_OBJECT_CONST: + { + Named_constant* named_constant = this->u_.const_value; + Translate_context subcontext(gogo, function, NULL, NULL_TREE); + tree expr_tree = named_constant->expr()->get_tree(&subcontext); + if (expr_tree == error_mark_node) + decl = error_mark_node; + else + { + Type* type = named_constant->type(); + if (type != NULL && !type->is_abstract()) + { + if (!type->is_undefined()) + expr_tree = fold_convert(type->get_tree(gogo), expr_tree); + else + { + // Make sure we report the error. + type->base(); + expr_tree = error_mark_node; + } + } + if (expr_tree == error_mark_node) + decl = error_mark_node; + else if (INTEGRAL_TYPE_P(TREE_TYPE(expr_tree))) + { + decl = build_decl(named_constant->location(), CONST_DECL, + name, TREE_TYPE(expr_tree)); + DECL_INITIAL(decl) = expr_tree; + TREE_CONSTANT(decl) = 1; + TREE_READONLY(decl) = 1; + } + else + { + // A CONST_DECL is only for an enum constant, so we + // shouldn't use for non-integral types. Instead we + // just return the constant itself, rather than a + // decl. + decl = expr_tree; + } + } + } + break; + + case NAMED_OBJECT_TYPE: + { + Named_type* named_type = this->u_.type_value; + tree type_tree = named_type->get_tree(gogo); + if (type_tree == error_mark_node) + decl = error_mark_node; + else + { + decl = TYPE_NAME(type_tree); + gcc_assert(decl != NULL_TREE); + + // We need to produce a type descriptor for every named + // type, and for a pointer to every named type, since + // other files or packages might refer to them. We need + // to do this even for hidden types, because they might + // still be returned by some function. Simply calling the + // type_descriptor method is enough to create the type + // descriptor, even though we don't do anything with it. + if (this->package_ == NULL) + { + named_type->type_descriptor_pointer(gogo); + Type* pn = Type::make_pointer_type(named_type); + pn->type_descriptor_pointer(gogo); + } + } + } + break; + + case NAMED_OBJECT_TYPE_DECLARATION: + error("reference to undefined type %qs", + this->message_name().c_str()); + return error_mark_node; + + case NAMED_OBJECT_VAR: + { + Variable* var = this->u_.var_value; + Type* type = var->type(); + if (type->is_error_type() + || (type->is_undefined() + && (!var->is_global() || this->package() == NULL))) + { + // Force the error for an undefined type, just in case. + type->base(); + decl = error_mark_node; + } + else + { + tree var_type = type->get_tree(gogo); + bool is_parameter = var->is_parameter(); + if (var->is_receiver() && type->points_to() == NULL) + is_parameter = false; + if (var->is_in_heap()) + { + is_parameter = false; + var_type = build_pointer_type(var_type); + } + decl = build_decl(var->location(), + is_parameter ? PARM_DECL : VAR_DECL, + name, var_type); + if (!var->is_global()) + { + tree fnid = function->get_id(gogo); + tree fndecl = function->func_value()->get_or_make_decl(gogo, + function, + fnid); + DECL_CONTEXT(decl) = fndecl; + } + if (is_parameter) + DECL_ARG_TYPE(decl) = TREE_TYPE(decl); + + if (var->is_global()) + { + const Package* package = this->package(); + if (package == NULL) + TREE_STATIC(decl) = 1; + else + DECL_EXTERNAL(decl) = 1; + if (!Gogo::is_hidden_name(this->name_)) + { + TREE_PUBLIC(decl) = 1; + std::string asm_name = (package == NULL + ? gogo->unique_prefix() + : package->unique_prefix()); + asm_name.append(1, '.'); + asm_name.append(IDENTIFIER_POINTER(name), + IDENTIFIER_LENGTH(name)); + tree asm_id = get_identifier_from_string(asm_name); + SET_DECL_ASSEMBLER_NAME(decl, asm_id); + } + } + + // FIXME: We should only set this for variables which are + // actually used somewhere. + TREE_USED(decl) = 1; + } + } + break; + + case NAMED_OBJECT_RESULT_VAR: + { + Result_variable* result = this->u_.result_var_value; + Type* type = result->type(); + if (type->is_error_type() || type->is_undefined()) + { + // Force the error. + type->base(); + decl = error_mark_node; + } + else + { + gcc_assert(result->function() == function->func_value()); + source_location loc = function->location(); + tree result_type = type->get_tree(gogo); + tree init; + if (!result->is_in_heap()) + init = type->get_init_tree(gogo, false); + else + { + tree space = gogo->allocate_memory(type, + TYPE_SIZE_UNIT(result_type), + loc); + result_type = build_pointer_type(result_type); + tree subinit = type->get_init_tree(gogo, true); + if (subinit == NULL_TREE) + init = fold_convert_loc(loc, result_type, space); + else + { + space = save_expr(space); + space = fold_convert_loc(loc, result_type, space); + tree spaceref = build_fold_indirect_ref_loc(loc, space); + TREE_THIS_NOTRAP(spaceref) = 1; + tree set = fold_build2_loc(loc, MODIFY_EXPR, void_type_node, + spaceref, subinit); + init = fold_build2_loc(loc, COMPOUND_EXPR, TREE_TYPE(space), + set, space); + } + } + decl = build_decl(loc, VAR_DECL, name, result_type); + tree fnid = function->get_id(gogo); + tree fndecl = function->func_value()->get_or_make_decl(gogo, + function, + fnid); + DECL_CONTEXT(decl) = fndecl; + DECL_INITIAL(decl) = init; + TREE_USED(decl) = 1; + } + } + break; + + case NAMED_OBJECT_SINK: + gcc_unreachable(); + + case NAMED_OBJECT_FUNC: + { + Function* func = this->u_.func_value; + decl = func->get_or_make_decl(gogo, this, name); + if (decl != error_mark_node) + { + if (func->block() != NULL) + { + if (DECL_STRUCT_FUNCTION(decl) == NULL) + push_struct_function(decl); + else + push_cfun(DECL_STRUCT_FUNCTION(decl)); + + cfun->function_end_locus = func->block()->end_location(); + + current_function_decl = decl; + + func->build_tree(gogo, this); + + gimplify_function_tree(decl); + + cgraph_finalize_function(decl, true); + + current_function_decl = NULL_TREE; + pop_cfun(); + } + } + } + break; + + default: + gcc_unreachable(); + } + + if (TREE_TYPE(decl) == error_mark_node) + decl = error_mark_node; + + tree ret = decl; + + // If this is a local variable whose address is taken, then we + // actually store it in the heap. For uses of the variable we need + // to return a reference to that heap location. + if (((this->classification_ == NAMED_OBJECT_VAR + && this->var_value()->is_in_heap()) + || (this->classification_ == NAMED_OBJECT_RESULT_VAR + && this->result_var_value()->is_in_heap())) + && ret != error_mark_node) + { + gcc_assert(POINTER_TYPE_P(TREE_TYPE(ret))); + ret = build_fold_indirect_ref(ret); + TREE_THIS_NOTRAP(ret) = 1; + } + + this->tree_ = ret; + + if (ret != error_mark_node) + go_preserve_from_gc(ret); + + return ret; +} + +// Get the initial value of a variable as a tree. This does not +// consider whether the variable is in the heap--it returns the +// initial value as though it were always stored in the stack. + +tree +Variable::get_init_tree(Gogo* gogo, Named_object* function) +{ + gcc_assert(this->preinit_ == NULL); + if (this->init_ == NULL) + { + gcc_assert(!this->is_parameter_); + return this->type_->get_init_tree(gogo, this->is_global_); + } + else + { + Translate_context context(gogo, function, NULL, NULL_TREE); + tree rhs_tree = this->init_->get_tree(&context); + return Expression::convert_for_assignment(&context, this->type(), + this->init_->type(), + rhs_tree, this->location()); + } +} + +// Get the initial value of a variable when a block is required. +// VAR_DECL is the decl to set; it may be NULL for a sink variable. + +tree +Variable::get_init_block(Gogo* gogo, Named_object* function, tree var_decl) +{ + gcc_assert(this->preinit_ != NULL); + + // We want to add the variable assignment to the end of the preinit + // block. The preinit block may have a TRY_FINALLY_EXPR and a + // TRY_CATCH_EXPR; if it does, we want to add to the end of the + // regular statements. + + Translate_context context(gogo, function, NULL, NULL_TREE); + tree block_tree = this->preinit_->get_tree(&context); + if (block_tree == error_mark_node) + return error_mark_node; + gcc_assert(TREE_CODE(block_tree) == BIND_EXPR); + tree statements = BIND_EXPR_BODY(block_tree); + while (statements != NULL_TREE + && (TREE_CODE(statements) == TRY_FINALLY_EXPR + || TREE_CODE(statements) == TRY_CATCH_EXPR)) + statements = TREE_OPERAND(statements, 0); + + // It's possible to have pre-init statements without an initializer + // if the pre-init statements set the variable. + if (this->init_ != NULL) + { + tree rhs_tree = this->init_->get_tree(&context); + if (rhs_tree == error_mark_node) + return error_mark_node; + if (var_decl == NULL_TREE) + append_to_statement_list(rhs_tree, &statements); + else + { + tree val = Expression::convert_for_assignment(&context, this->type(), + this->init_->type(), + rhs_tree, + this->location()); + if (val == error_mark_node) + return error_mark_node; + tree set = fold_build2_loc(this->location(), MODIFY_EXPR, + void_type_node, var_decl, val); + append_to_statement_list(set, &statements); + } + } + + return block_tree; +} + +// Get a tree for a function decl. + +tree +Function::get_or_make_decl(Gogo* gogo, Named_object* no, tree id) +{ + if (this->fndecl_ == NULL_TREE) + { + tree functype = this->type_->get_tree(gogo); + if (functype == error_mark_node) + this->fndecl_ = error_mark_node; + else + { + // The type of a function comes back as a pointer, but we + // want the real function type for a function declaration. + gcc_assert(POINTER_TYPE_P(functype)); + functype = TREE_TYPE(functype); + tree decl = build_decl(this->location(), FUNCTION_DECL, id, functype); + + this->fndecl_ = decl; + + if (no->package() != NULL) + ; + else if (this->enclosing_ != NULL || Gogo::is_thunk(no)) + ; + else if (Gogo::unpack_hidden_name(no->name()) == "init" + && !this->type_->is_method()) + ; + else if (Gogo::unpack_hidden_name(no->name()) == "main" + && gogo->is_main_package()) + TREE_PUBLIC(decl) = 1; + // Methods have to be public even if they are hidden because + // they can be pulled into type descriptors when using + // anonymous fields. + else if (!Gogo::is_hidden_name(no->name()) + || this->type_->is_method()) + { + TREE_PUBLIC(decl) = 1; + std::string asm_name = gogo->unique_prefix(); + asm_name.append(1, '.'); + asm_name.append(IDENTIFIER_POINTER(id), IDENTIFIER_LENGTH(id)); + SET_DECL_ASSEMBLER_NAME(decl, + get_identifier_from_string(asm_name)); + } + + // Why do we have to do this in the frontend? + tree restype = TREE_TYPE(functype); + tree resdecl = build_decl(this->location(), RESULT_DECL, NULL_TREE, + restype); + DECL_ARTIFICIAL(resdecl) = 1; + DECL_IGNORED_P(resdecl) = 1; + DECL_CONTEXT(resdecl) = decl; + DECL_RESULT(decl) = resdecl; + + if (this->enclosing_ != NULL) + DECL_STATIC_CHAIN(decl) = 1; + + // If a function calls the predeclared recover function, we + // can't inline it, because recover behaves differently in a + // function passed directly to defer. + if (this->calls_recover_ && !this->is_recover_thunk_) + DECL_UNINLINABLE(decl) = 1; + + // If this is a thunk created to call a function which calls + // the predeclared recover function, we need to disable + // stack splitting for the thunk. + if (this->is_recover_thunk_) + { + tree attr = get_identifier("__no_split_stack__"); + DECL_ATTRIBUTES(decl) = tree_cons(attr, NULL_TREE, NULL_TREE); + } + + go_preserve_from_gc(decl); + + if (this->closure_var_ != NULL) + { + push_struct_function(decl); + + tree closure_decl = this->closure_var_->get_tree(gogo, no); + if (closure_decl == error_mark_node) + this->fndecl_ = error_mark_node; + else + { + DECL_ARTIFICIAL(closure_decl) = 1; + DECL_IGNORED_P(closure_decl) = 1; + TREE_USED(closure_decl) = 1; + DECL_ARG_TYPE(closure_decl) = TREE_TYPE(closure_decl); + TREE_READONLY(closure_decl) = 1; + + DECL_STRUCT_FUNCTION(decl)->static_chain_decl = closure_decl; + } + + pop_cfun(); + } + } + } + return this->fndecl_; +} + +// Get a tree for a function declaration. + +tree +Function_declaration::get_or_make_decl(Gogo* gogo, Named_object* no, tree id) +{ + if (this->fndecl_ == NULL_TREE) + { + // Let Go code use an asm declaration to pick up a builtin + // function. + if (!this->asm_name_.empty()) + { + std::map<std::string, tree>::const_iterator p = + builtin_functions.find(this->asm_name_); + if (p != builtin_functions.end()) + { + this->fndecl_ = p->second; + return this->fndecl_; + } + } + + tree functype = this->fntype_->get_tree(gogo); + tree decl; + if (functype == error_mark_node) + decl = error_mark_node; + else + { + // The type of a function comes back as a pointer, but we + // want the real function type for a function declaration. + gcc_assert(POINTER_TYPE_P(functype)); + functype = TREE_TYPE(functype); + decl = build_decl(this->location(), FUNCTION_DECL, id, functype); + TREE_PUBLIC(decl) = 1; + DECL_EXTERNAL(decl) = 1; + + if (this->asm_name_.empty()) + { + std::string asm_name = (no->package() == NULL + ? gogo->unique_prefix() + : no->package()->unique_prefix()); + asm_name.append(1, '.'); + asm_name.append(IDENTIFIER_POINTER(id), IDENTIFIER_LENGTH(id)); + SET_DECL_ASSEMBLER_NAME(decl, + get_identifier_from_string(asm_name)); + } + } + this->fndecl_ = decl; + go_preserve_from_gc(decl); + } + return this->fndecl_; +} + +// We always pass the receiver to a method as a pointer. If the +// receiver is actually declared as a non-pointer type, then we copy +// the value into a local variable, so that it has the right type. In +// this function we create the real PARM_DECL to use, and set +// DEC_INITIAL of the var_decl to be the value passed in. + +tree +Function::make_receiver_parm_decl(Gogo* gogo, Named_object* no, tree var_decl) +{ + if (var_decl == error_mark_node) + return error_mark_node; + // If the function takes the address of a receiver which is passed + // by value, then we will have an INDIRECT_REF here. We need to get + // the real variable. + bool is_in_heap = no->var_value()->is_in_heap(); + tree val_type; + if (TREE_CODE(var_decl) != INDIRECT_REF) + { + gcc_assert(!is_in_heap); + val_type = TREE_TYPE(var_decl); + } + else + { + gcc_assert(is_in_heap); + var_decl = TREE_OPERAND(var_decl, 0); + if (var_decl == error_mark_node) + return error_mark_node; + gcc_assert(POINTER_TYPE_P(TREE_TYPE(var_decl))); + val_type = TREE_TYPE(TREE_TYPE(var_decl)); + } + gcc_assert(TREE_CODE(var_decl) == VAR_DECL); + source_location loc = DECL_SOURCE_LOCATION(var_decl); + std::string name = IDENTIFIER_POINTER(DECL_NAME(var_decl)); + name += ".pointer"; + tree id = get_identifier_from_string(name); + tree parm_decl = build_decl(loc, PARM_DECL, id, build_pointer_type(val_type)); + DECL_CONTEXT(parm_decl) = current_function_decl; + DECL_ARG_TYPE(parm_decl) = TREE_TYPE(parm_decl); + + gcc_assert(DECL_INITIAL(var_decl) == NULL_TREE); + // The receiver might be passed as a null pointer. + tree check = fold_build2_loc(loc, NE_EXPR, boolean_type_node, parm_decl, + fold_convert_loc(loc, TREE_TYPE(parm_decl), + null_pointer_node)); + tree ind = build_fold_indirect_ref_loc(loc, parm_decl); + TREE_THIS_NOTRAP(ind) = 1; + tree zero_init = no->var_value()->type()->get_init_tree(gogo, false); + tree init = fold_build3_loc(loc, COND_EXPR, TREE_TYPE(ind), + check, ind, zero_init); + + if (is_in_heap) + { + tree size = TYPE_SIZE_UNIT(val_type); + tree space = gogo->allocate_memory(no->var_value()->type(), size, + no->location()); + space = save_expr(space); + space = fold_convert(build_pointer_type(val_type), space); + tree spaceref = build_fold_indirect_ref_loc(no->location(), space); + TREE_THIS_NOTRAP(spaceref) = 1; + tree check = fold_build2_loc(loc, NE_EXPR, boolean_type_node, + parm_decl, + fold_convert_loc(loc, TREE_TYPE(parm_decl), + null_pointer_node)); + tree parmref = build_fold_indirect_ref_loc(no->location(), parm_decl); + TREE_THIS_NOTRAP(parmref) = 1; + tree set = fold_build2_loc(loc, MODIFY_EXPR, void_type_node, + spaceref, parmref); + init = fold_build2_loc(loc, COMPOUND_EXPR, TREE_TYPE(space), + build3(COND_EXPR, void_type_node, + check, set, NULL_TREE), + space); + } + + DECL_INITIAL(var_decl) = init; + + return parm_decl; +} + +// If we take the address of a parameter, then we need to copy it into +// the heap. We will access it as a local variable via an +// indirection. + +tree +Function::copy_parm_to_heap(Gogo* gogo, Named_object* no, tree ref) +{ + if (ref == error_mark_node) + return error_mark_node; + + gcc_assert(TREE_CODE(ref) == INDIRECT_REF); + + tree var_decl = TREE_OPERAND(ref, 0); + if (var_decl == error_mark_node) + return error_mark_node; + gcc_assert(TREE_CODE(var_decl) == VAR_DECL); + source_location loc = DECL_SOURCE_LOCATION(var_decl); + + std::string name = IDENTIFIER_POINTER(DECL_NAME(var_decl)); + name += ".param"; + tree id = get_identifier_from_string(name); + + tree type = TREE_TYPE(var_decl); + gcc_assert(POINTER_TYPE_P(type)); + type = TREE_TYPE(type); + + tree parm_decl = build_decl(loc, PARM_DECL, id, type); + DECL_CONTEXT(parm_decl) = current_function_decl; + DECL_ARG_TYPE(parm_decl) = type; + + tree size = TYPE_SIZE_UNIT(type); + tree space = gogo->allocate_memory(no->var_value()->type(), size, loc); + space = save_expr(space); + space = fold_convert(TREE_TYPE(var_decl), space); + tree spaceref = build_fold_indirect_ref_loc(loc, space); + TREE_THIS_NOTRAP(spaceref) = 1; + tree init = build2(COMPOUND_EXPR, TREE_TYPE(space), + build2(MODIFY_EXPR, void_type_node, spaceref, parm_decl), + space); + DECL_INITIAL(var_decl) = init; + + return parm_decl; +} + +// Get a tree for function code. + +void +Function::build_tree(Gogo* gogo, Named_object* named_function) +{ + tree fndecl = this->fndecl_; + gcc_assert(fndecl != NULL_TREE); + + tree params = NULL_TREE; + tree* pp = ¶ms; + + tree declare_vars = NULL_TREE; + for (Bindings::const_definitions_iterator p = + this->block_->bindings()->begin_definitions(); + p != this->block_->bindings()->end_definitions(); + ++p) + { + if ((*p)->is_variable() && (*p)->var_value()->is_parameter()) + { + *pp = (*p)->get_tree(gogo, named_function); + + // We always pass the receiver to a method as a pointer. If + // the receiver is declared as a non-pointer type, then we + // copy the value into a local variable. + if ((*p)->var_value()->is_receiver() + && (*p)->var_value()->type()->points_to() == NULL) + { + tree parm_decl = this->make_receiver_parm_decl(gogo, *p, *pp); + tree var = *pp; + if (TREE_CODE(var) == INDIRECT_REF) + var = TREE_OPERAND(var, 0); + if (var != error_mark_node) + { + gcc_assert(TREE_CODE(var) == VAR_DECL); + DECL_CHAIN(var) = declare_vars; + declare_vars = var; + } + *pp = parm_decl; + } + else if ((*p)->var_value()->is_in_heap()) + { + // If we take the address of a parameter, then we need + // to copy it into the heap. + tree parm_decl = this->copy_parm_to_heap(gogo, *p, *pp); + if (*pp != error_mark_node) + { + gcc_assert(TREE_CODE(*pp) == INDIRECT_REF); + tree var_decl = TREE_OPERAND(*pp, 0); + if (var_decl != error_mark_node) + { + gcc_assert(TREE_CODE(var_decl) == VAR_DECL); + DECL_CHAIN(var_decl) = declare_vars; + declare_vars = var_decl; + } + } + *pp = parm_decl; + } + + if (*pp != error_mark_node) + { + gcc_assert(TREE_CODE(*pp) == PARM_DECL); + pp = &DECL_CHAIN(*pp); + } + } + else if ((*p)->is_result_variable()) + { + tree var_decl = (*p)->get_tree(gogo, named_function); + if (var_decl != error_mark_node + && (*p)->result_var_value()->is_in_heap()) + { + gcc_assert(TREE_CODE(var_decl) == INDIRECT_REF); + var_decl = TREE_OPERAND(var_decl, 0); + } + if (var_decl != error_mark_node) + { + gcc_assert(TREE_CODE(var_decl) == VAR_DECL); + DECL_CHAIN(var_decl) = declare_vars; + declare_vars = var_decl; + } + } + } + *pp = NULL_TREE; + + DECL_ARGUMENTS(fndecl) = params; + + if (this->block_ != NULL) + { + gcc_assert(DECL_INITIAL(fndecl) == NULL_TREE); + + // Declare variables if necessary. + tree bind = NULL_TREE; + if (declare_vars != NULL_TREE) + { + tree block = make_node(BLOCK); + BLOCK_SUPERCONTEXT(block) = fndecl; + DECL_INITIAL(fndecl) = block; + BLOCK_VARS(block) = declare_vars; + TREE_USED(block) = 1; + bind = build3(BIND_EXPR, void_type_node, BLOCK_VARS(block), + NULL_TREE, block); + TREE_SIDE_EFFECTS(bind) = 1; + } + + // Build the trees for all the statements in the function. + Translate_context context(gogo, named_function, NULL, NULL_TREE); + tree code = this->block_->get_tree(&context); + + tree init = NULL_TREE; + tree except = NULL_TREE; + tree fini = NULL_TREE; + + // Initialize variables if necessary. + for (tree v = declare_vars; v != NULL_TREE; v = DECL_CHAIN(v)) + { + tree dv = build1(DECL_EXPR, void_type_node, v); + SET_EXPR_LOCATION(dv, DECL_SOURCE_LOCATION(v)); + append_to_statement_list(dv, &init); + } + + // If we have a defer stack, initialize it at the start of a + // function. + if (this->defer_stack_ != NULL_TREE) + { + tree defer_init = build1(DECL_EXPR, void_type_node, + this->defer_stack_); + SET_EXPR_LOCATION(defer_init, this->block_->start_location()); + append_to_statement_list(defer_init, &init); + + // Clean up the defer stack when we leave the function. + this->build_defer_wrapper(gogo, named_function, &except, &fini); + } + + if (code != NULL_TREE && code != error_mark_node) + { + if (init != NULL_TREE) + code = build2(COMPOUND_EXPR, void_type_node, init, code); + if (except != NULL_TREE) + code = build2(TRY_CATCH_EXPR, void_type_node, code, + build2(CATCH_EXPR, void_type_node, NULL, except)); + if (fini != NULL_TREE) + code = build2(TRY_FINALLY_EXPR, void_type_node, code, fini); + } + + // Stick the code into the block we built for the receiver, if + // we built on. + if (bind != NULL_TREE && code != NULL_TREE && code != error_mark_node) + { + BIND_EXPR_BODY(bind) = code; + code = bind; + } + + DECL_SAVED_TREE(fndecl) = code; + } +} + +// Build the wrappers around function code needed if the function has +// any defer statements. This sets *EXCEPT to an exception handler +// and *FINI to a finally handler. + +void +Function::build_defer_wrapper(Gogo* gogo, Named_object* named_function, + tree *except, tree *fini) +{ + source_location end_loc = this->block_->end_location(); + + // Add an exception handler. This is used if a panic occurs. Its + // purpose is to stop the stack unwinding if a deferred function + // calls recover. There are more details in + // libgo/runtime/go-unwind.c. + tree stmt_list = NULL_TREE; + static tree check_fndecl; + tree call = Gogo::call_builtin(&check_fndecl, + end_loc, + "__go_check_defer", + 1, + void_type_node, + ptr_type_node, + this->defer_stack(end_loc)); + if (call != error_mark_node) + append_to_statement_list(call, &stmt_list); + + tree retval = this->return_value(gogo, named_function, end_loc, &stmt_list); + tree set; + if (retval == NULL_TREE) + set = NULL_TREE; + else + set = fold_build2_loc(end_loc, MODIFY_EXPR, void_type_node, + DECL_RESULT(this->fndecl_), retval); + tree ret_stmt = fold_build1_loc(end_loc, RETURN_EXPR, void_type_node, set); + append_to_statement_list(ret_stmt, &stmt_list); + + gcc_assert(*except == NULL_TREE); + *except = stmt_list; + + // Add some finally code to run the defer functions. This is used + // both in the normal case, when no panic occurs, and also if a + // panic occurs to run any further defer functions. Of course, it + // is possible for a defer function to call panic which should be + // caught by another defer function. To handle that we use a loop. + // finish: + // try { __go_undefer(); } catch { __go_check_defer(); goto finish; } + // if (return values are named) return named_vals; + + stmt_list = NULL; + + tree label = create_artificial_label(end_loc); + tree define_label = fold_build1_loc(end_loc, LABEL_EXPR, void_type_node, + label); + append_to_statement_list(define_label, &stmt_list); + + static tree undefer_fndecl; + tree undefer = Gogo::call_builtin(&undefer_fndecl, + end_loc, + "__go_undefer", + 1, + void_type_node, + ptr_type_node, + this->defer_stack(end_loc)); + if (undefer_fndecl != NULL_TREE) + TREE_NOTHROW(undefer_fndecl) = 0; + + tree defer = Gogo::call_builtin(&check_fndecl, + end_loc, + "__go_check_defer", + 1, + void_type_node, + ptr_type_node, + this->defer_stack(end_loc)); + tree jump = fold_build1_loc(end_loc, GOTO_EXPR, void_type_node, label); + tree catch_body = build2(COMPOUND_EXPR, void_type_node, defer, jump); + catch_body = build2(CATCH_EXPR, void_type_node, NULL, catch_body); + tree try_catch = build2(TRY_CATCH_EXPR, void_type_node, undefer, catch_body); + + append_to_statement_list(try_catch, &stmt_list); + + if (this->type_->results() != NULL + && !this->type_->results()->empty() + && !this->type_->results()->front().name().empty()) + { + // If the result variables are named, we need to return them + // again, because they might have been changed by a defer + // function. + retval = this->return_value(gogo, named_function, end_loc, + &stmt_list); + set = fold_build2_loc(end_loc, MODIFY_EXPR, void_type_node, + DECL_RESULT(this->fndecl_), retval); + ret_stmt = fold_build1_loc(end_loc, RETURN_EXPR, void_type_node, set); + append_to_statement_list(ret_stmt, &stmt_list); + } + + gcc_assert(*fini == NULL_TREE); + *fini = stmt_list; +} + +// Return the value to assign to DECL_RESULT(this->fndecl_). This may +// also add statements to STMT_LIST, which need to be executed before +// the assignment. This is used for a return statement with no +// explicit values. + +tree +Function::return_value(Gogo* gogo, Named_object* named_function, + source_location location, tree* stmt_list) const +{ + const Typed_identifier_list* results = this->type_->results(); + if (results == NULL || results->empty()) + return NULL_TREE; + + // In the case of an exception handler created for functions with + // defer statements, the result variables may be unnamed. + bool is_named = !results->front().name().empty(); + if (is_named) + { + gcc_assert(this->named_results_ != NULL); + if (this->named_results_->size() != results->size()) + { + gcc_assert(saw_errors()); + return error_mark_node; + } + } + + tree retval; + if (results->size() == 1) + { + if (is_named) + return this->named_results_->front()->get_tree(gogo, named_function); + else + return results->front().type()->get_init_tree(gogo, false); + } + else + { + tree rettype = TREE_TYPE(DECL_RESULT(this->fndecl_)); + retval = create_tmp_var(rettype, "RESULT"); + tree field = TYPE_FIELDS(rettype); + int index = 0; + for (Typed_identifier_list::const_iterator pr = results->begin(); + pr != results->end(); + ++pr, ++index, field = DECL_CHAIN(field)) + { + gcc_assert(field != NULL); + tree val; + if (is_named) + val = (*this->named_results_)[index]->get_tree(gogo, + named_function); + else + val = pr->type()->get_init_tree(gogo, false); + tree set = fold_build2_loc(location, MODIFY_EXPR, void_type_node, + build3(COMPONENT_REF, TREE_TYPE(field), + retval, field, NULL_TREE), + val); + append_to_statement_list(set, stmt_list); + } + return retval; + } +} + +// Get the tree for the variable holding the defer stack for this +// function. At least at present, the value of this variable is not +// used. However, a pointer to this variable is used as a marker for +// the functions on the defer stack associated with this function. +// Doing things this way permits inlining a function which uses defer. + +tree +Function::defer_stack(source_location location) +{ + if (this->defer_stack_ == NULL_TREE) + { + tree var = create_tmp_var(ptr_type_node, "DEFER"); + DECL_INITIAL(var) = null_pointer_node; + DECL_SOURCE_LOCATION(var) = location; + TREE_ADDRESSABLE(var) = 1; + this->defer_stack_ = var; + } + return fold_convert_loc(location, ptr_type_node, + build_fold_addr_expr_loc(location, + this->defer_stack_)); +} + +// Get a tree for the statements in a block. + +tree +Block::get_tree(Translate_context* context) +{ + Gogo* gogo = context->gogo(); + + tree block = make_node(BLOCK); + + // Put the new block into the block tree. + + if (context->block() == NULL) + { + tree fndecl; + if (context->function() != NULL) + fndecl = context->function()->func_value()->get_decl(); + else + fndecl = current_function_decl; + gcc_assert(fndecl != NULL_TREE); + + // We may have already created a block for the receiver. + if (DECL_INITIAL(fndecl) == NULL_TREE) + { + BLOCK_SUPERCONTEXT(block) = fndecl; + DECL_INITIAL(fndecl) = block; + } + else + { + tree superblock_tree = DECL_INITIAL(fndecl); + BLOCK_SUPERCONTEXT(block) = superblock_tree; + gcc_assert(BLOCK_CHAIN(block) == NULL_TREE); + BLOCK_CHAIN(block) = block; + } + } + else + { + tree superblock_tree = context->block_tree(); + BLOCK_SUPERCONTEXT(block) = superblock_tree; + tree* pp; + for (pp = &BLOCK_SUBBLOCKS(superblock_tree); + *pp != NULL_TREE; + pp = &BLOCK_CHAIN(*pp)) + ; + *pp = block; + } + + // Expand local variables in the block. + + tree* pp = &BLOCK_VARS(block); + for (Bindings::const_definitions_iterator pv = + this->bindings_->begin_definitions(); + pv != this->bindings_->end_definitions(); + ++pv) + { + if ((!(*pv)->is_variable() || !(*pv)->var_value()->is_parameter()) + && !(*pv)->is_result_variable() + && !(*pv)->is_const()) + { + tree var = (*pv)->get_tree(gogo, context->function()); + if (var != error_mark_node && TREE_TYPE(var) != error_mark_node) + { + if ((*pv)->is_variable() && (*pv)->var_value()->is_in_heap()) + { + gcc_assert(TREE_CODE(var) == INDIRECT_REF); + var = TREE_OPERAND(var, 0); + gcc_assert(TREE_CODE(var) == VAR_DECL); + } + *pp = var; + pp = &DECL_CHAIN(*pp); + } + } + } + *pp = NULL_TREE; + + Translate_context subcontext(context->gogo(), context->function(), + this, block); + + tree statements = NULL_TREE; + + // Expand the statements. + + for (std::vector<Statement*>::const_iterator p = this->statements_.begin(); + p != this->statements_.end(); + ++p) + { + tree statement = (*p)->get_tree(&subcontext); + if (statement != error_mark_node) + append_to_statement_list(statement, &statements); + } + + TREE_USED(block) = 1; + + tree bind = build3(BIND_EXPR, void_type_node, BLOCK_VARS(block), statements, + block); + TREE_SIDE_EFFECTS(bind) = 1; + + return bind; +} + +// Get the LABEL_DECL for a label. + +tree +Label::get_decl() +{ + if (this->decl_ == NULL) + { + tree id = get_identifier_from_string(this->name_); + this->decl_ = build_decl(this->location_, LABEL_DECL, id, void_type_node); + DECL_CONTEXT(this->decl_) = current_function_decl; + } + return this->decl_; +} + +// Return an expression for the address of this label. + +tree +Label::get_addr(source_location location) +{ + tree decl = this->get_decl(); + TREE_USED(decl) = 1; + TREE_ADDRESSABLE(decl) = 1; + return fold_convert_loc(location, ptr_type_node, + build_fold_addr_expr_loc(location, decl)); +} + +// Get the LABEL_DECL for an unnamed label. + +tree +Unnamed_label::get_decl() +{ + if (this->decl_ == NULL) + this->decl_ = create_artificial_label(this->location_); + return this->decl_; +} + +// Get the LABEL_EXPR for an unnamed label. + +tree +Unnamed_label::get_definition() +{ + tree t = build1(LABEL_EXPR, void_type_node, this->get_decl()); + SET_EXPR_LOCATION(t, this->location_); + return t; +} + +// Return a goto to this label. + +tree +Unnamed_label::get_goto(source_location location) +{ + tree t = build1(GOTO_EXPR, void_type_node, this->get_decl()); + SET_EXPR_LOCATION(t, location); + return t; +} + +// Return the integer type to use for a size. + +GO_EXTERN_C +tree +go_type_for_size(unsigned int bits, int unsignedp) +{ + const char* name; + switch (bits) + { + case 8: + name = unsignedp ? "uint8" : "int8"; + break; + case 16: + name = unsignedp ? "uint16" : "int16"; + break; + case 32: + name = unsignedp ? "uint32" : "int32"; + break; + case 64: + name = unsignedp ? "uint64" : "int64"; + break; + default: + if (bits == POINTER_SIZE && unsignedp) + name = "uintptr"; + else + return NULL_TREE; + } + Type* type = Type::lookup_integer_type(name); + return type->get_tree(go_get_gogo()); +} + +// Return the type to use for a mode. + +GO_EXTERN_C +tree +go_type_for_mode(enum machine_mode mode, int unsignedp) +{ + // FIXME: This static_cast should be in machmode.h. + enum mode_class mc = static_cast<enum mode_class>(GET_MODE_CLASS(mode)); + if (mc == MODE_INT) + return go_type_for_size(GET_MODE_BITSIZE(mode), unsignedp); + else if (mc == MODE_FLOAT) + { + Type* type; + switch (GET_MODE_BITSIZE (mode)) + { + case 32: + type = Type::lookup_float_type("float32"); + break; + case 64: + type = Type::lookup_float_type("float64"); + break; + default: + // We have to check for long double in order to support + // i386 excess precision. + if (mode == TYPE_MODE(long_double_type_node)) + return long_double_type_node; + return NULL_TREE; + } + return type->float_type()->type_tree(); + } + else if (mc == MODE_COMPLEX_FLOAT) + { + Type *type; + switch (GET_MODE_BITSIZE (mode)) + { + case 64: + type = Type::lookup_complex_type("complex64"); + break; + case 128: + type = Type::lookup_complex_type("complex128"); + break; + default: + // We have to check for long double in order to support + // i386 excess precision. + if (mode == TYPE_MODE(complex_long_double_type_node)) + return complex_long_double_type_node; + return NULL_TREE; + } + return type->complex_type()->type_tree(); + } + else + return NULL_TREE; +} + +// Return a tree which allocates SIZE bytes which will holds value of +// type TYPE. + +tree +Gogo::allocate_memory(Type* type, tree size, source_location location) +{ + // If the package imports unsafe, then it may play games with + // pointers that look like integers. + if (this->imported_unsafe_ || type->has_pointer()) + { + static tree new_fndecl; + return Gogo::call_builtin(&new_fndecl, + location, + "__go_new", + 1, + ptr_type_node, + sizetype, + size); + } + else + { + static tree new_nopointers_fndecl; + return Gogo::call_builtin(&new_nopointers_fndecl, + location, + "__go_new_nopointers", + 1, + ptr_type_node, + sizetype, + size); + } +} + +// Build a builtin struct with a list of fields. The name is +// STRUCT_NAME. STRUCT_TYPE is NULL_TREE or an empty RECORD_TYPE +// node; this exists so that the struct can have fields which point to +// itself. If PTYPE is not NULL, store the result in *PTYPE. There +// are NFIELDS fields. Each field is a name (a const char*) followed +// by a type (a tree). + +tree +Gogo::builtin_struct(tree* ptype, const char* struct_name, tree struct_type, + int nfields, ...) +{ + if (ptype != NULL && *ptype != NULL_TREE) + return *ptype; + + va_list ap; + va_start(ap, nfields); + + tree fields = NULL_TREE; + for (int i = 0; i < nfields; ++i) + { + const char* field_name = va_arg(ap, const char*); + tree type = va_arg(ap, tree); + if (type == error_mark_node) + { + if (ptype != NULL) + *ptype = error_mark_node; + return error_mark_node; + } + tree field = build_decl(BUILTINS_LOCATION, FIELD_DECL, + get_identifier(field_name), type); + DECL_CHAIN(field) = fields; + fields = field; + } + + va_end(ap); + + if (struct_type == NULL_TREE) + struct_type = make_node(RECORD_TYPE); + finish_builtin_struct(struct_type, struct_name, fields, NULL_TREE); + + if (ptype != NULL) + { + go_preserve_from_gc(struct_type); + *ptype = struct_type; + } + + return struct_type; +} + +// Return a type to use for pointer to const char for a string. + +tree +Gogo::const_char_pointer_type_tree() +{ + static tree type; + if (type == NULL_TREE) + { + tree const_char_type = build_qualified_type(unsigned_char_type_node, + TYPE_QUAL_CONST); + type = build_pointer_type(const_char_type); + go_preserve_from_gc(type); + } + return type; +} + +// Return a tree for a string constant. + +tree +Gogo::string_constant_tree(const std::string& val) +{ + tree index_type = build_index_type(size_int(val.length())); + tree const_char_type = build_qualified_type(unsigned_char_type_node, + TYPE_QUAL_CONST); + tree string_type = build_array_type(const_char_type, index_type); + string_type = build_variant_type_copy(string_type); + TYPE_STRING_FLAG(string_type) = 1; + tree string_val = build_string(val.length(), val.data()); + TREE_TYPE(string_val) = string_type; + return string_val; +} + +// Return a tree for a Go string constant. + +tree +Gogo::go_string_constant_tree(const std::string& val) +{ + tree string_type = Type::make_string_type()->get_tree(this); + + VEC(constructor_elt, gc)* init = VEC_alloc(constructor_elt, gc, 2); + + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + tree field = TYPE_FIELDS(string_type); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__data") == 0); + elt->index = field; + tree str = Gogo::string_constant_tree(val); + elt->value = fold_convert(TREE_TYPE(field), + build_fold_addr_expr(str)); + + elt = VEC_quick_push(constructor_elt, init, NULL); + field = DECL_CHAIN(field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__length") == 0); + elt->index = field; + elt->value = build_int_cst_type(TREE_TYPE(field), val.length()); + + tree constructor = build_constructor(string_type, init); + TREE_READONLY(constructor) = 1; + TREE_CONSTANT(constructor) = 1; + + return constructor; +} + +// Return a tree for a pointer to a Go string constant. This is only +// used for type descriptors, so we return a pointer to a constant +// decl. + +tree +Gogo::ptr_go_string_constant_tree(const std::string& val) +{ + tree pval = this->go_string_constant_tree(val); + + tree decl = build_decl(UNKNOWN_LOCATION, VAR_DECL, + create_tmp_var_name("SP"), TREE_TYPE(pval)); + DECL_EXTERNAL(decl) = 0; + TREE_PUBLIC(decl) = 0; + TREE_USED(decl) = 1; + TREE_READONLY(decl) = 1; + TREE_CONSTANT(decl) = 1; + TREE_STATIC(decl) = 1; + DECL_ARTIFICIAL(decl) = 1; + DECL_INITIAL(decl) = pval; + rest_of_decl_compilation(decl, 1, 0); + + return build_fold_addr_expr(decl); +} + +// Build the type of the struct that holds a slice for the given +// element type. + +tree +Gogo::slice_type_tree(tree element_type_tree) +{ + // We use int for the count and capacity fields in a slice header. + // This matches 6g. The language definition guarantees that we + // can't allocate space of a size which does not fit in int + // anyhow. FIXME: integer_type_node is the the C type "int" but is + // not necessarily the Go type "int". They will differ when the C + // type "int" has fewer than 32 bits. + return Gogo::builtin_struct(NULL, "__go_slice", NULL_TREE, 3, + "__values", + build_pointer_type(element_type_tree), + "__count", + integer_type_node, + "__capacity", + integer_type_node); +} + +// Given the tree for a slice type, return the tree for the type of +// the elements of the slice. + +tree +Gogo::slice_element_type_tree(tree slice_type_tree) +{ + gcc_assert(TREE_CODE(slice_type_tree) == RECORD_TYPE + && POINTER_TYPE_P(TREE_TYPE(TYPE_FIELDS(slice_type_tree)))); + return TREE_TYPE(TREE_TYPE(TYPE_FIELDS(slice_type_tree))); +} + +// Build a constructor for a slice. SLICE_TYPE_TREE is the type of +// the slice. VALUES is the value pointer and COUNT is the number of +// entries. If CAPACITY is not NULL, it is the capacity; otherwise +// the capacity and the count are the same. + +tree +Gogo::slice_constructor(tree slice_type_tree, tree values, tree count, + tree capacity) +{ + gcc_assert(TREE_CODE(slice_type_tree) == RECORD_TYPE); + + VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 3); + + tree field = TYPE_FIELDS(slice_type_tree); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__values") == 0); + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + elt->index = field; + gcc_assert(TYPE_MAIN_VARIANT(TREE_TYPE(field)) + == TYPE_MAIN_VARIANT(TREE_TYPE(values))); + elt->value = values; + + count = fold_convert(sizetype, count); + if (capacity == NULL_TREE) + { + count = save_expr(count); + capacity = count; + } + + field = DECL_CHAIN(field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__count") == 0); + elt = VEC_quick_push(constructor_elt, init, NULL); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), count); + + field = DECL_CHAIN(field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__capacity") == 0); + elt = VEC_quick_push(constructor_elt, init, NULL); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), capacity); + + return build_constructor(slice_type_tree, init); +} + +// Build a constructor for an empty slice. + +tree +Gogo::empty_slice_constructor(tree slice_type_tree) +{ + tree element_field = TYPE_FIELDS(slice_type_tree); + tree ret = Gogo::slice_constructor(slice_type_tree, + fold_convert(TREE_TYPE(element_field), + null_pointer_node), + size_zero_node, + size_zero_node); + TREE_CONSTANT(ret) = 1; + return ret; +} + +// Build a map descriptor for a map of type MAPTYPE. + +tree +Gogo::map_descriptor(Map_type* maptype) +{ + if (this->map_descriptors_ == NULL) + this->map_descriptors_ = new Map_descriptors(10); + + std::pair<const Map_type*, tree> val(maptype, NULL); + std::pair<Map_descriptors::iterator, bool> ins = + this->map_descriptors_->insert(val); + Map_descriptors::iterator p = ins.first; + if (!ins.second) + { + if (p->second == error_mark_node) + return error_mark_node; + gcc_assert(p->second != NULL_TREE && DECL_P(p->second)); + return build_fold_addr_expr(p->second); + } + + Type* keytype = maptype->key_type(); + Type* valtype = maptype->val_type(); + + std::string mangled_name = ("__go_map_" + maptype->mangled_name(this)); + + tree id = get_identifier_from_string(mangled_name); + + // Get the type of the map descriptor. This is __go_map_descriptor + // in libgo/map.h. + + tree struct_type = this->map_descriptor_type(); + + // The map entry type is a struct with three fields. This struct is + // specific to MAPTYPE. Build it. + + tree map_entry_type = make_node(RECORD_TYPE); + + map_entry_type = Gogo::builtin_struct(NULL, "__map", map_entry_type, 3, + "__next", + build_pointer_type(map_entry_type), + "__key", + keytype->get_tree(this), + "__val", + valtype->get_tree(this)); + if (map_entry_type == error_mark_node) + { + p->second = error_mark_node; + return error_mark_node; + } + + tree map_entry_key_field = DECL_CHAIN(TYPE_FIELDS(map_entry_type)); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(map_entry_key_field)), + "__key") == 0); + + tree map_entry_val_field = DECL_CHAIN(map_entry_key_field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(map_entry_val_field)), + "__val") == 0); + + // Initialize the entries. + + tree map_descriptor_field = TYPE_FIELDS(struct_type); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(map_descriptor_field)), + "__map_descriptor") == 0); + tree entry_size_field = DECL_CHAIN(map_descriptor_field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(entry_size_field)), + "__entry_size") == 0); + tree key_offset_field = DECL_CHAIN(entry_size_field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(key_offset_field)), + "__key_offset") == 0); + tree val_offset_field = DECL_CHAIN(key_offset_field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(val_offset_field)), + "__val_offset") == 0); + + VEC(constructor_elt, gc)* descriptor = VEC_alloc(constructor_elt, gc, 6); + + constructor_elt* elt = VEC_quick_push(constructor_elt, descriptor, NULL); + elt->index = map_descriptor_field; + elt->value = maptype->type_descriptor_pointer(this); + + elt = VEC_quick_push(constructor_elt, descriptor, NULL); + elt->index = entry_size_field; + elt->value = TYPE_SIZE_UNIT(map_entry_type); + + elt = VEC_quick_push(constructor_elt, descriptor, NULL); + elt->index = key_offset_field; + elt->value = byte_position(map_entry_key_field); + + elt = VEC_quick_push(constructor_elt, descriptor, NULL); + elt->index = val_offset_field; + elt->value = byte_position(map_entry_val_field); + + tree constructor = build_constructor(struct_type, descriptor); + + tree decl = build_decl(BUILTINS_LOCATION, VAR_DECL, id, struct_type); + TREE_STATIC(decl) = 1; + TREE_USED(decl) = 1; + TREE_READONLY(decl) = 1; + TREE_CONSTANT(decl) = 1; + DECL_INITIAL(decl) = constructor; + make_decl_one_only(decl, DECL_ASSEMBLER_NAME(decl)); + resolve_unique_section(decl, 1, 0); + + rest_of_decl_compilation(decl, 1, 0); + + go_preserve_from_gc(decl); + p->second = decl; + + return build_fold_addr_expr(decl); +} + +// Return a tree for the type of a map descriptor. This is struct +// __go_map_descriptor in libgo/runtime/map.h. This is the same for +// all map types. + +tree +Gogo::map_descriptor_type() +{ + static tree struct_type; + tree dtype = Type::make_type_descriptor_type()->get_tree(this); + dtype = build_qualified_type(dtype, TYPE_QUAL_CONST); + return Gogo::builtin_struct(&struct_type, "__go_map_descriptor", NULL_TREE, + 4, + "__map_descriptor", + build_pointer_type(dtype), + "__entry_size", + sizetype, + "__key_offset", + sizetype, + "__val_offset", + sizetype); +} + +// Return the name to use for a type descriptor decl for TYPE. This +// is used when TYPE does not have a name. + +std::string +Gogo::unnamed_type_descriptor_decl_name(const Type* type) +{ + return "__go_td_" + type->mangled_name(this); +} + +// Return the name to use for a type descriptor decl for a type named +// NAME, defined in the function IN_FUNCTION. IN_FUNCTION will +// normally be NULL. + +std::string +Gogo::type_descriptor_decl_name(const Named_object* no, + const Named_object* in_function) +{ + std::string ret = "__go_tdn_"; + if (no->type_value()->is_builtin()) + gcc_assert(in_function == NULL); + else + { + const std::string& unique_prefix(no->package() == NULL + ? this->unique_prefix() + : no->package()->unique_prefix()); + const std::string& package_name(no->package() == NULL + ? this->package_name() + : no->package()->name()); + ret.append(unique_prefix); + ret.append(1, '.'); + ret.append(package_name); + ret.append(1, '.'); + if (in_function != NULL) + { + ret.append(Gogo::unpack_hidden_name(in_function->name())); + ret.append(1, '.'); + } + } + ret.append(no->name()); + return ret; +} + +// Where a type descriptor decl should be defined. + +Gogo::Type_descriptor_location +Gogo::type_descriptor_location(const Type* type) +{ + const Named_type* name = type->named_type(); + if (name != NULL) + { + if (name->named_object()->package() != NULL) + { + // This is a named type defined in a different package. The + // descriptor should be defined in that package. + return TYPE_DESCRIPTOR_UNDEFINED; + } + else if (name->is_builtin()) + { + // We create the descriptor for a builtin type whenever we + // need it. + return TYPE_DESCRIPTOR_COMMON; + } + else + { + // This is a named type defined in this package. The + // descriptor should be defined here. + return TYPE_DESCRIPTOR_DEFINED; + } + } + else + { + if (type->points_to() != NULL + && type->points_to()->named_type() != NULL + && type->points_to()->named_type()->named_object()->package() != NULL) + { + // This is an unnamed pointer to a named type defined in a + // different package. The descriptor should be defined in + // that package. + return TYPE_DESCRIPTOR_UNDEFINED; + } + else + { + // This is an unnamed type. The descriptor could be defined + // in any package where it is needed, and the linker will + // pick one descriptor to keep. + return TYPE_DESCRIPTOR_COMMON; + } + } +} + +// Build a type descriptor decl for TYPE. INITIALIZER is a struct +// composite literal which initializers the type descriptor. + +void +Gogo::build_type_descriptor_decl(const Type* type, Expression* initializer, + tree* pdecl) +{ + const Named_type* name = type->named_type(); + + // We can have multiple instances of unnamed types, but we only want + // to emit the type descriptor once. We use a hash table to handle + // this. This is not necessary for named types, as they are unique, + // and we store the type descriptor decl in the type itself. + tree* phash = NULL; + if (name == NULL) + { + if (this->type_descriptor_decls_ == NULL) + this->type_descriptor_decls_ = new Type_descriptor_decls(10); + + std::pair<Type_descriptor_decls::iterator, bool> ins = + this->type_descriptor_decls_->insert(std::make_pair(type, NULL_TREE)); + if (!ins.second) + { + // We've already built a type descriptor for this type. + *pdecl = ins.first->second; + return; + } + phash = &ins.first->second; + } + + std::string decl_name; + if (name == NULL) + decl_name = this->unnamed_type_descriptor_decl_name(type); + else + decl_name = this->type_descriptor_decl_name(name->named_object(), + name->in_function()); + tree id = get_identifier_from_string(decl_name); + tree descriptor_type_tree = initializer->type()->get_tree(this); + if (descriptor_type_tree == error_mark_node) + { + *pdecl = error_mark_node; + return; + } + tree decl = build_decl(name == NULL ? BUILTINS_LOCATION : name->location(), + VAR_DECL, id, + build_qualified_type(descriptor_type_tree, + TYPE_QUAL_CONST)); + TREE_READONLY(decl) = 1; + TREE_CONSTANT(decl) = 1; + DECL_ARTIFICIAL(decl) = 1; + + go_preserve_from_gc(decl); + if (phash != NULL) + *phash = decl; + + // We store the new DECL now because we may need to refer to it when + // expanding INITIALIZER. + *pdecl = decl; + + // If appropriate, just refer to the exported type identifier. + Gogo::Type_descriptor_location type_descriptor_location = + this->type_descriptor_location(type); + if (type_descriptor_location == TYPE_DESCRIPTOR_UNDEFINED) + { + TREE_PUBLIC(decl) = 1; + DECL_EXTERNAL(decl) = 1; + return; + } + + TREE_STATIC(decl) = 1; + TREE_USED(decl) = 1; + + Translate_context context(this, NULL, NULL, NULL); + context.set_is_const(); + tree constructor = initializer->get_tree(&context); + + if (constructor == error_mark_node) + gcc_assert(saw_errors()); + + DECL_INITIAL(decl) = constructor; + + if (type_descriptor_location == TYPE_DESCRIPTOR_DEFINED) + TREE_PUBLIC(decl) = 1; + else + { + gcc_assert(type_descriptor_location == TYPE_DESCRIPTOR_COMMON); + make_decl_one_only(decl, DECL_ASSEMBLER_NAME(decl)); + resolve_unique_section(decl, 1, 0); + } + + rest_of_decl_compilation(decl, 1, 0); +} + +// Build an interface method table for a type: a list of function +// pointers, one for each interface method. This is used for +// interfaces. + +tree +Gogo::interface_method_table_for_type(const Interface_type* interface, + Named_type* type, + bool is_pointer) +{ + const Typed_identifier_list* interface_methods = interface->methods(); + gcc_assert(!interface_methods->empty()); + + std::string mangled_name = ((is_pointer ? "__go_pimt__" : "__go_imt_") + + interface->mangled_name(this) + + "__" + + type->mangled_name(this)); + + tree id = get_identifier_from_string(mangled_name); + + // See whether this interface has any hidden methods. + bool has_hidden_methods = false; + for (Typed_identifier_list::const_iterator p = interface_methods->begin(); + p != interface_methods->end(); + ++p) + { + if (Gogo::is_hidden_name(p->name())) + { + has_hidden_methods = true; + break; + } + } + + // We already know that the named type is convertible to the + // interface. If the interface has hidden methods, and the named + // type is defined in a different package, then the interface + // conversion table will be defined by that other package. + if (has_hidden_methods && type->named_object()->package() != NULL) + { + tree array_type = build_array_type(const_ptr_type_node, NULL); + tree decl = build_decl(BUILTINS_LOCATION, VAR_DECL, id, array_type); + TREE_READONLY(decl) = 1; + TREE_CONSTANT(decl) = 1; + TREE_PUBLIC(decl) = 1; + DECL_EXTERNAL(decl) = 1; + go_preserve_from_gc(decl); + return decl; + } + + size_t count = interface_methods->size(); + VEC(constructor_elt, gc)* pointers = VEC_alloc(constructor_elt, gc, + count + 1); + + // The first element is the type descriptor. + constructor_elt* elt = VEC_quick_push(constructor_elt, pointers, NULL); + elt->index = size_zero_node; + Type* td_type; + if (!is_pointer) + td_type = type; + else + td_type = Type::make_pointer_type(type); + elt->value = fold_convert(const_ptr_type_node, + td_type->type_descriptor_pointer(this)); + + size_t i = 1; + for (Typed_identifier_list::const_iterator p = interface_methods->begin(); + p != interface_methods->end(); + ++p, ++i) + { + bool is_ambiguous; + Method* m = type->method_function(p->name(), &is_ambiguous); + gcc_assert(m != NULL); + + Named_object* no = m->named_object(); + + tree fnid = no->get_id(this); + + tree fndecl; + if (no->is_function()) + fndecl = no->func_value()->get_or_make_decl(this, no, fnid); + else if (no->is_function_declaration()) + fndecl = no->func_declaration_value()->get_or_make_decl(this, no, + fnid); + else + gcc_unreachable(); + fndecl = build_fold_addr_expr(fndecl); + + elt = VEC_quick_push(constructor_elt, pointers, NULL); + elt->index = size_int(i); + elt->value = fold_convert(const_ptr_type_node, fndecl); + } + gcc_assert(i == count + 1); + + tree array_type = build_array_type(const_ptr_type_node, + build_index_type(size_int(count))); + tree constructor = build_constructor(array_type, pointers); + + tree decl = build_decl(BUILTINS_LOCATION, VAR_DECL, id, array_type); + TREE_STATIC(decl) = 1; + TREE_USED(decl) = 1; + TREE_READONLY(decl) = 1; + TREE_CONSTANT(decl) = 1; + DECL_INITIAL(decl) = constructor; + + // If the interface type has hidden methods, then this is the only + // definition of the table. Otherwise it is a comdat table which + // may be defined in multiple packages. + if (has_hidden_methods) + TREE_PUBLIC(decl) = 1; + else + { + make_decl_one_only(decl, DECL_ASSEMBLER_NAME(decl)); + resolve_unique_section(decl, 1, 0); + } + + rest_of_decl_compilation(decl, 1, 0); + + go_preserve_from_gc(decl); + + return decl; +} + +// Mark a function as a builtin library function. + +void +Gogo::mark_fndecl_as_builtin_library(tree fndecl) +{ + DECL_EXTERNAL(fndecl) = 1; + TREE_PUBLIC(fndecl) = 1; + DECL_ARTIFICIAL(fndecl) = 1; + TREE_NOTHROW(fndecl) = 1; + DECL_VISIBILITY(fndecl) = VISIBILITY_DEFAULT; + DECL_VISIBILITY_SPECIFIED(fndecl) = 1; +} + +// Build a call to a builtin function. + +tree +Gogo::call_builtin(tree* pdecl, source_location location, const char* name, + int nargs, tree rettype, ...) +{ + if (rettype == error_mark_node) + return error_mark_node; + + tree* types = new tree[nargs]; + tree* args = new tree[nargs]; + + va_list ap; + va_start(ap, rettype); + for (int i = 0; i < nargs; ++i) + { + types[i] = va_arg(ap, tree); + args[i] = va_arg(ap, tree); + if (types[i] == error_mark_node || args[i] == error_mark_node) + { + delete[] types; + delete[] args; + return error_mark_node; + } + } + va_end(ap); + + if (*pdecl == NULL_TREE) + { + tree fnid = get_identifier(name); + + tree argtypes = NULL_TREE; + tree* pp = &argtypes; + for (int i = 0; i < nargs; ++i) + { + *pp = tree_cons(NULL_TREE, types[i], NULL_TREE); + pp = &TREE_CHAIN(*pp); + } + *pp = void_list_node; + + tree fntype = build_function_type(rettype, argtypes); + + *pdecl = build_decl(BUILTINS_LOCATION, FUNCTION_DECL, fnid, fntype); + Gogo::mark_fndecl_as_builtin_library(*pdecl); + go_preserve_from_gc(*pdecl); + } + + tree fnptr = build_fold_addr_expr(*pdecl); + if (CAN_HAVE_LOCATION_P(fnptr)) + SET_EXPR_LOCATION(fnptr, location); + + tree ret = build_call_array(rettype, fnptr, nargs, args); + SET_EXPR_LOCATION(ret, location); + + delete[] types; + delete[] args; + + return ret; +} + +// Build a call to the runtime error function. + +tree +Gogo::runtime_error(int code, source_location location) +{ + static tree runtime_error_fndecl; + tree ret = Gogo::call_builtin(&runtime_error_fndecl, + location, + "__go_runtime_error", + 1, + void_type_node, + integer_type_node, + build_int_cst(integer_type_node, code)); + if (ret == error_mark_node) + return error_mark_node; + // The runtime error function panics and does not return. + TREE_NOTHROW(runtime_error_fndecl) = 0; + TREE_THIS_VOLATILE(runtime_error_fndecl) = 1; + return ret; +} + +// Send VAL on CHANNEL. If BLOCKING is true, the resulting tree has a +// void type. If BLOCKING is false, the resulting tree has a boolean +// type, and it will evaluate as true if the value was sent. If +// FOR_SELECT is true, this is being done because it was chosen in a +// select statement. + +tree +Gogo::send_on_channel(tree channel, tree val, bool blocking, bool for_select, + source_location location) +{ + if (channel == error_mark_node || val == error_mark_node) + return error_mark_node; + + if (int_size_in_bytes(TREE_TYPE(val)) <= 8 + && !AGGREGATE_TYPE_P(TREE_TYPE(val)) + && !FLOAT_TYPE_P(TREE_TYPE(val))) + { + val = convert_to_integer(uint64_type_node, val); + if (blocking) + { + static tree send_small_fndecl; + tree ret = Gogo::call_builtin(&send_small_fndecl, + location, + "__go_send_small", + 3, + void_type_node, + ptr_type_node, + channel, + uint64_type_node, + val, + boolean_type_node, + (for_select + ? boolean_true_node + : boolean_false_node)); + if (ret == error_mark_node) + return error_mark_node; + // This can panic if there are too many operations on a + // closed channel. + TREE_NOTHROW(send_small_fndecl) = 0; + return ret; + } + else + { + gcc_assert(!for_select); + static tree send_nonblocking_small_fndecl; + tree ret = Gogo::call_builtin(&send_nonblocking_small_fndecl, + location, + "__go_send_nonblocking_small", + 2, + boolean_type_node, + ptr_type_node, + channel, + uint64_type_node, + val); + if (ret == error_mark_node) + return error_mark_node; + // This can panic if there are too many operations on a + // closed channel. + TREE_NOTHROW(send_nonblocking_small_fndecl) = 0; + return ret; + } + } + else + { + tree make_tmp; + if (TREE_ADDRESSABLE(TREE_TYPE(val)) || TREE_CODE(val) == VAR_DECL) + { + make_tmp = NULL_TREE; + val = build_fold_addr_expr(val); + if (DECL_P(val)) + TREE_ADDRESSABLE(val) = 1; + } + else + { + tree tmp = create_tmp_var(TREE_TYPE(val), get_name(val)); + DECL_IGNORED_P(tmp) = 0; + DECL_INITIAL(tmp) = val; + TREE_ADDRESSABLE(tmp) = 1; + make_tmp = build1(DECL_EXPR, void_type_node, tmp); + SET_EXPR_LOCATION(make_tmp, location); + val = build_fold_addr_expr(tmp); + } + val = fold_convert(ptr_type_node, val); + + tree call; + if (blocking) + { + static tree send_big_fndecl; + call = Gogo::call_builtin(&send_big_fndecl, + location, + "__go_send_big", + 3, + void_type_node, + ptr_type_node, + channel, + ptr_type_node, + val, + boolean_type_node, + (for_select + ? boolean_true_node + : boolean_false_node)); + if (call == error_mark_node) + return error_mark_node; + // This can panic if there are too many operations on a + // closed channel. + TREE_NOTHROW(send_big_fndecl) = 0; + } + else + { + gcc_assert(!for_select); + static tree send_nonblocking_big_fndecl; + call = Gogo::call_builtin(&send_nonblocking_big_fndecl, + location, + "__go_send_nonblocking_big", + 2, + boolean_type_node, + ptr_type_node, + channel, + ptr_type_node, + val); + if (call == error_mark_node) + return error_mark_node; + // This can panic if there are too many operations on a + // closed channel. + TREE_NOTHROW(send_nonblocking_big_fndecl) = 0; + } + + if (make_tmp == NULL_TREE) + return call; + else + { + tree ret = build2(COMPOUND_EXPR, TREE_TYPE(call), make_tmp, call); + SET_EXPR_LOCATION(ret, location); + return ret; + } + } +} + +// Return a tree for receiving a value of type TYPE_TREE on CHANNEL. +// This does a blocking receive and returns the value read from the +// channel. If FOR_SELECT is true, this is being done because it was +// chosen in a select statement. + +tree +Gogo::receive_from_channel(tree type_tree, tree channel, bool for_select, + source_location location) +{ + if (type_tree == error_mark_node || channel == error_mark_node) + return error_mark_node; + + if (int_size_in_bytes(type_tree) <= 8 + && !AGGREGATE_TYPE_P(type_tree) + && !FLOAT_TYPE_P(type_tree)) + { + static tree receive_small_fndecl; + tree call = Gogo::call_builtin(&receive_small_fndecl, + location, + "__go_receive_small", + 2, + uint64_type_node, + ptr_type_node, + channel, + boolean_type_node, + (for_select + ? boolean_true_node + : boolean_false_node)); + if (call == error_mark_node) + return error_mark_node; + // This can panic if there are too many operations on a closed + // channel. + TREE_NOTHROW(receive_small_fndecl) = 0; + int bitsize = GET_MODE_BITSIZE(TYPE_MODE(type_tree)); + tree int_type_tree = go_type_for_size(bitsize, 1); + return fold_convert_loc(location, type_tree, + fold_convert_loc(location, int_type_tree, + call)); + } + else + { + tree tmp = create_tmp_var(type_tree, get_name(type_tree)); + DECL_IGNORED_P(tmp) = 0; + TREE_ADDRESSABLE(tmp) = 1; + tree make_tmp = build1(DECL_EXPR, void_type_node, tmp); + SET_EXPR_LOCATION(make_tmp, location); + tree tmpaddr = build_fold_addr_expr(tmp); + tmpaddr = fold_convert(ptr_type_node, tmpaddr); + static tree receive_big_fndecl; + tree call = Gogo::call_builtin(&receive_big_fndecl, + location, + "__go_receive_big", + 3, + void_type_node, + ptr_type_node, + channel, + ptr_type_node, + tmpaddr, + boolean_type_node, + (for_select + ? boolean_true_node + : boolean_false_node)); + if (call == error_mark_node) + return error_mark_node; + // This can panic if there are too many operations on a closed + // channel. + TREE_NOTHROW(receive_big_fndecl) = 0; + return build2(COMPOUND_EXPR, type_tree, make_tmp, + build2(COMPOUND_EXPR, type_tree, call, tmp)); + } +} + +// Return the type of a function trampoline. This is like +// get_trampoline_type in tree-nested.c. + +tree +Gogo::trampoline_type_tree() +{ + static tree type_tree; + if (type_tree == NULL_TREE) + { + unsigned int size; + unsigned int align; + go_trampoline_info(&size, &align); + tree t = build_index_type(build_int_cst(integer_type_node, size - 1)); + t = build_array_type(char_type_node, t); + + type_tree = Gogo::builtin_struct(NULL, "__go_trampoline", NULL_TREE, 1, + "__data", t); + t = TYPE_FIELDS(type_tree); + DECL_ALIGN(t) = align; + DECL_USER_ALIGN(t) = 1; + + go_preserve_from_gc(type_tree); + } + return type_tree; +} + +// Make a trampoline which calls FNADDR passing CLOSURE. + +tree +Gogo::make_trampoline(tree fnaddr, tree closure, source_location location) +{ + tree trampoline_type = Gogo::trampoline_type_tree(); + tree trampoline_size = TYPE_SIZE_UNIT(trampoline_type); + + closure = save_expr(closure); + + // We allocate the trampoline using a special function which will + // mark it as executable. + static tree trampoline_fndecl; + tree x = Gogo::call_builtin(&trampoline_fndecl, + location, + "__go_allocate_trampoline", + 2, + ptr_type_node, + size_type_node, + trampoline_size, + ptr_type_node, + fold_convert_loc(location, ptr_type_node, + closure)); + if (x == error_mark_node) + return error_mark_node; + + x = save_expr(x); + + // Initialize the trampoline. + tree ini = build_call_expr(implicit_built_in_decls[BUILT_IN_INIT_TRAMPOLINE], + 3, x, fnaddr, closure); + + // On some targets the trampoline address needs to be adjusted. For + // example, when compiling in Thumb mode on the ARM, the address + // needs to have the low bit set. + x = build_call_expr(implicit_built_in_decls[BUILT_IN_ADJUST_TRAMPOLINE], + 1, x); + x = fold_convert(TREE_TYPE(fnaddr), x); + + return build2(COMPOUND_EXPR, TREE_TYPE(x), ini, x); +} diff --git a/gcc/go/gofrontend/gogo.cc b/gcc/go/gofrontend/gogo.cc new file mode 100644 index 000000000..f8c143c9c --- /dev/null +++ b/gcc/go/gofrontend/gogo.cc @@ -0,0 +1,4519 @@ +// gogo.cc -- Go frontend parsed representation. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include "go-c.h" +#include "go-dump.h" +#include "lex.h" +#include "types.h" +#include "statements.h" +#include "expressions.h" +#include "dataflow.h" +#include "import.h" +#include "export.h" +#include "gogo.h" + +// Class Gogo. + +Gogo::Gogo(int int_type_size, int pointer_size) + : package_(NULL), + functions_(), + globals_(new Bindings(NULL)), + imports_(), + imported_unsafe_(false), + packages_(), + map_descriptors_(NULL), + type_descriptor_decls_(NULL), + init_functions_(), + need_init_fn_(false), + init_fn_name_(), + imported_init_fns_(), + unique_prefix_(), + unique_prefix_specified_(false), + interface_types_(), + named_types_are_converted_(false) +{ + const source_location loc = BUILTINS_LOCATION; + + Named_type* uint8_type = Type::make_integer_type("uint8", true, 8, + RUNTIME_TYPE_KIND_UINT8); + this->add_named_type(uint8_type); + this->add_named_type(Type::make_integer_type("uint16", true, 16, + RUNTIME_TYPE_KIND_UINT16)); + this->add_named_type(Type::make_integer_type("uint32", true, 32, + RUNTIME_TYPE_KIND_UINT32)); + this->add_named_type(Type::make_integer_type("uint64", true, 64, + RUNTIME_TYPE_KIND_UINT64)); + + this->add_named_type(Type::make_integer_type("int8", false, 8, + RUNTIME_TYPE_KIND_INT8)); + this->add_named_type(Type::make_integer_type("int16", false, 16, + RUNTIME_TYPE_KIND_INT16)); + this->add_named_type(Type::make_integer_type("int32", false, 32, + RUNTIME_TYPE_KIND_INT32)); + this->add_named_type(Type::make_integer_type("int64", false, 64, + RUNTIME_TYPE_KIND_INT64)); + + this->add_named_type(Type::make_float_type("float32", 32, + RUNTIME_TYPE_KIND_FLOAT32)); + this->add_named_type(Type::make_float_type("float64", 64, + RUNTIME_TYPE_KIND_FLOAT64)); + + this->add_named_type(Type::make_complex_type("complex64", 64, + RUNTIME_TYPE_KIND_COMPLEX64)); + this->add_named_type(Type::make_complex_type("complex128", 128, + RUNTIME_TYPE_KIND_COMPLEX128)); + + if (int_type_size < 32) + int_type_size = 32; + this->add_named_type(Type::make_integer_type("uint", true, + int_type_size, + RUNTIME_TYPE_KIND_UINT)); + Named_type* int_type = Type::make_integer_type("int", false, int_type_size, + RUNTIME_TYPE_KIND_INT); + this->add_named_type(int_type); + + // "byte" is an alias for "uint8". Construct a Named_object which + // points to UINT8_TYPE. Note that this breaks the normal pairing + // in which a Named_object points to a Named_type which points back + // to the same Named_object. + Named_object* byte_type = this->declare_type("byte", loc); + byte_type->set_type_value(uint8_type); + + this->add_named_type(Type::make_integer_type("uintptr", true, + pointer_size, + RUNTIME_TYPE_KIND_UINTPTR)); + + this->add_named_type(Type::make_named_bool_type()); + + this->add_named_type(Type::make_named_string_type()); + + this->globals_->add_constant(Typed_identifier("true", + Type::make_boolean_type(), + loc), + NULL, + Expression::make_boolean(true, loc), + 0); + this->globals_->add_constant(Typed_identifier("false", + Type::make_boolean_type(), + loc), + NULL, + Expression::make_boolean(false, loc), + 0); + + this->globals_->add_constant(Typed_identifier("nil", Type::make_nil_type(), + loc), + NULL, + Expression::make_nil(loc), + 0); + + Type* abstract_int_type = Type::make_abstract_integer_type(); + this->globals_->add_constant(Typed_identifier("iota", abstract_int_type, + loc), + NULL, + Expression::make_iota(), + 0); + + Function_type* new_type = Type::make_function_type(NULL, NULL, NULL, loc); + new_type->set_is_varargs(); + new_type->set_is_builtin(); + this->globals_->add_function_declaration("new", NULL, new_type, loc); + + Function_type* make_type = Type::make_function_type(NULL, NULL, NULL, loc); + make_type->set_is_varargs(); + make_type->set_is_builtin(); + this->globals_->add_function_declaration("make", NULL, make_type, loc); + + Typed_identifier_list* len_result = new Typed_identifier_list(); + len_result->push_back(Typed_identifier("", int_type, loc)); + Function_type* len_type = Type::make_function_type(NULL, NULL, len_result, + loc); + len_type->set_is_builtin(); + this->globals_->add_function_declaration("len", NULL, len_type, loc); + + Typed_identifier_list* cap_result = new Typed_identifier_list(); + cap_result->push_back(Typed_identifier("", int_type, loc)); + Function_type* cap_type = Type::make_function_type(NULL, NULL, len_result, + loc); + cap_type->set_is_builtin(); + this->globals_->add_function_declaration("cap", NULL, cap_type, loc); + + Function_type* print_type = Type::make_function_type(NULL, NULL, NULL, loc); + print_type->set_is_varargs(); + print_type->set_is_builtin(); + this->globals_->add_function_declaration("print", NULL, print_type, loc); + + print_type = Type::make_function_type(NULL, NULL, NULL, loc); + print_type->set_is_varargs(); + print_type->set_is_builtin(); + this->globals_->add_function_declaration("println", NULL, print_type, loc); + + Type *empty = Type::make_interface_type(NULL, loc); + Typed_identifier_list* panic_parms = new Typed_identifier_list(); + panic_parms->push_back(Typed_identifier("e", empty, loc)); + Function_type *panic_type = Type::make_function_type(NULL, panic_parms, + NULL, loc); + panic_type->set_is_builtin(); + this->globals_->add_function_declaration("panic", NULL, panic_type, loc); + + Typed_identifier_list* recover_result = new Typed_identifier_list(); + recover_result->push_back(Typed_identifier("", empty, loc)); + Function_type* recover_type = Type::make_function_type(NULL, NULL, + recover_result, + loc); + recover_type->set_is_builtin(); + this->globals_->add_function_declaration("recover", NULL, recover_type, loc); + + Function_type* close_type = Type::make_function_type(NULL, NULL, NULL, loc); + close_type->set_is_varargs(); + close_type->set_is_builtin(); + this->globals_->add_function_declaration("close", NULL, close_type, loc); + + Typed_identifier_list* closed_result = new Typed_identifier_list(); + closed_result->push_back(Typed_identifier("", Type::lookup_bool_type(), + loc)); + Function_type* closed_type = Type::make_function_type(NULL, NULL, + closed_result, loc); + closed_type->set_is_varargs(); + closed_type->set_is_builtin(); + this->globals_->add_function_declaration("closed", NULL, closed_type, loc); + + Typed_identifier_list* copy_result = new Typed_identifier_list(); + copy_result->push_back(Typed_identifier("", int_type, loc)); + Function_type* copy_type = Type::make_function_type(NULL, NULL, + copy_result, loc); + copy_type->set_is_varargs(); + copy_type->set_is_builtin(); + this->globals_->add_function_declaration("copy", NULL, copy_type, loc); + + Function_type* append_type = Type::make_function_type(NULL, NULL, NULL, loc); + append_type->set_is_varargs(); + append_type->set_is_builtin(); + this->globals_->add_function_declaration("append", NULL, append_type, loc); + + Function_type* complex_type = Type::make_function_type(NULL, NULL, NULL, loc); + complex_type->set_is_varargs(); + complex_type->set_is_builtin(); + this->globals_->add_function_declaration("complex", NULL, complex_type, loc); + + Function_type* real_type = Type::make_function_type(NULL, NULL, NULL, loc); + real_type->set_is_varargs(); + real_type->set_is_builtin(); + this->globals_->add_function_declaration("real", NULL, real_type, loc); + + Function_type* imag_type = Type::make_function_type(NULL, NULL, NULL, loc); + imag_type->set_is_varargs(); + imag_type->set_is_builtin(); + this->globals_->add_function_declaration("imag", NULL, imag_type, loc); + + this->define_builtin_function_trees(); +} + +// Munge name for use in an error message. + +std::string +Gogo::message_name(const std::string& name) +{ + return go_localize_identifier(Gogo::unpack_hidden_name(name).c_str()); +} + +// Get the package name. + +const std::string& +Gogo::package_name() const +{ + gcc_assert(this->package_ != NULL); + return this->package_->name(); +} + +// Set the package name. + +void +Gogo::set_package_name(const std::string& package_name, + source_location location) +{ + if (this->package_ != NULL && this->package_->name() != package_name) + { + error_at(location, "expected package %<%s%>", + Gogo::message_name(this->package_->name()).c_str()); + return; + } + + // If the user did not specify a unique prefix, we always use "go". + // This in effect requires that the package name be unique. + if (this->unique_prefix_.empty()) + this->unique_prefix_ = "go"; + + this->package_ = this->register_package(package_name, this->unique_prefix_, + location); + + // We used to permit people to qualify symbols with the current + // package name (e.g., P.x), but we no longer do. + // this->globals_->add_package(package_name, this->package_); + + if (this->is_main_package()) + { + // Declare "main" as a function which takes no parameters and + // returns no value. + this->declare_function("main", + Type::make_function_type(NULL, NULL, NULL, + BUILTINS_LOCATION), + BUILTINS_LOCATION); + } +} + +// Return whether this is the "main" package. This is not true if +// -fgo-prefix was used. + +bool +Gogo::is_main_package() const +{ + return this->package_name() == "main" && !this->unique_prefix_specified_; +} + +// Import a package. + +void +Gogo::import_package(const std::string& filename, + const std::string& local_name, + bool is_local_name_exported, + source_location location) +{ + if (filename == "unsafe") + { + this->import_unsafe(local_name, is_local_name_exported, location); + return; + } + + Imports::const_iterator p = this->imports_.find(filename); + if (p != this->imports_.end()) + { + Package* package = p->second; + package->set_location(location); + package->set_is_imported(); + std::string ln = local_name; + bool is_ln_exported = is_local_name_exported; + if (ln.empty()) + { + ln = package->name(); + is_ln_exported = Lex::is_exported_name(ln); + } + if (ln == ".") + { + Bindings* bindings = package->bindings(); + for (Bindings::const_declarations_iterator p = + bindings->begin_declarations(); + p != bindings->end_declarations(); + ++p) + this->add_named_object(p->second); + } + else if (ln == "_") + package->set_uses_sink_alias(); + else + { + ln = this->pack_hidden_name(ln, is_ln_exported); + this->package_->bindings()->add_package(ln, package); + } + return; + } + + Import::Stream* stream = Import::open_package(filename, location); + if (stream == NULL) + { + error_at(location, "import file %qs not found", filename.c_str()); + return; + } + + Import imp(stream, location); + imp.register_builtin_types(this); + Package* package = imp.import(this, local_name, is_local_name_exported); + if (package != NULL) + { + if (package->name() == this->package_name() + && package->unique_prefix() == this->unique_prefix()) + error_at(location, + ("imported package uses same package name and prefix " + "as package being compiled (see -fgo-prefix option)")); + + this->imports_.insert(std::make_pair(filename, package)); + package->set_is_imported(); + } + + delete stream; +} + +// Add an import control function for an imported package to the list. + +void +Gogo::add_import_init_fn(const std::string& package_name, + const std::string& init_name, int prio) +{ + for (std::set<Import_init>::const_iterator p = + this->imported_init_fns_.begin(); + p != this->imported_init_fns_.end(); + ++p) + { + if (p->init_name() == init_name + && (p->package_name() != package_name || p->priority() != prio)) + { + error("duplicate package initialization name %qs", + Gogo::message_name(init_name).c_str()); + inform(UNKNOWN_LOCATION, "used by package %qs at priority %d", + Gogo::message_name(p->package_name()).c_str(), + p->priority()); + inform(UNKNOWN_LOCATION, " and by package %qs at priority %d", + Gogo::message_name(package_name).c_str(), prio); + return; + } + } + + this->imported_init_fns_.insert(Import_init(package_name, init_name, + prio)); +} + +// Return whether we are at the global binding level. + +bool +Gogo::in_global_scope() const +{ + return this->functions_.empty(); +} + +// Return the current binding contour. + +Bindings* +Gogo::current_bindings() +{ + if (!this->functions_.empty()) + return this->functions_.back().blocks.back()->bindings(); + else if (this->package_ != NULL) + return this->package_->bindings(); + else + return this->globals_; +} + +const Bindings* +Gogo::current_bindings() const +{ + if (!this->functions_.empty()) + return this->functions_.back().blocks.back()->bindings(); + else if (this->package_ != NULL) + return this->package_->bindings(); + else + return this->globals_; +} + +// Return the current block. + +Block* +Gogo::current_block() +{ + if (this->functions_.empty()) + return NULL; + else + return this->functions_.back().blocks.back(); +} + +// Look up a name in the current binding contour. If PFUNCTION is not +// NULL, set it to the function in which the name is defined, or NULL +// if the name is defined in global scope. + +Named_object* +Gogo::lookup(const std::string& name, Named_object** pfunction) const +{ + if (pfunction != NULL) + *pfunction = NULL; + + if (Gogo::is_sink_name(name)) + return Named_object::make_sink(); + + for (Open_functions::const_reverse_iterator p = this->functions_.rbegin(); + p != this->functions_.rend(); + ++p) + { + Named_object* ret = p->blocks.back()->bindings()->lookup(name); + if (ret != NULL) + { + if (pfunction != NULL) + *pfunction = p->function; + return ret; + } + } + + if (this->package_ != NULL) + { + Named_object* ret = this->package_->bindings()->lookup(name); + if (ret != NULL) + { + if (ret->package() != NULL) + ret->package()->set_used(); + return ret; + } + } + + // We do not look in the global namespace. If we did, the global + // namespace would effectively hide names which were defined in + // package scope which we have not yet seen. Instead, + // define_global_names is called after parsing is over to connect + // undefined names at package scope with names defined at global + // scope. + + return NULL; +} + +// Look up a name in the current block, without searching enclosing +// blocks. + +Named_object* +Gogo::lookup_in_block(const std::string& name) const +{ + gcc_assert(!this->functions_.empty()); + gcc_assert(!this->functions_.back().blocks.empty()); + return this->functions_.back().blocks.back()->bindings()->lookup_local(name); +} + +// Look up a name in the global namespace. + +Named_object* +Gogo::lookup_global(const char* name) const +{ + return this->globals_->lookup(name); +} + +// Add an imported package. + +Package* +Gogo::add_imported_package(const std::string& real_name, + const std::string& alias_arg, + bool is_alias_exported, + const std::string& unique_prefix, + source_location location, + bool* padd_to_globals) +{ + // FIXME: Now that we compile packages as a whole, should we permit + // importing the current package? + if (this->package_name() == real_name + && this->unique_prefix() == unique_prefix) + { + *padd_to_globals = false; + if (!alias_arg.empty() && alias_arg != ".") + { + std::string alias = this->pack_hidden_name(alias_arg, + is_alias_exported); + this->package_->bindings()->add_package(alias, this->package_); + } + return this->package_; + } + else if (alias_arg == ".") + { + *padd_to_globals = true; + return this->register_package(real_name, unique_prefix, location); + } + else if (alias_arg == "_") + { + Package* ret = this->register_package(real_name, unique_prefix, location); + ret->set_uses_sink_alias(); + return ret; + } + else + { + *padd_to_globals = false; + std::string alias = alias_arg; + if (alias.empty()) + { + alias = real_name; + is_alias_exported = Lex::is_exported_name(alias); + } + alias = this->pack_hidden_name(alias, is_alias_exported); + Named_object* no = this->add_package(real_name, alias, unique_prefix, + location); + if (!no->is_package()) + return NULL; + return no->package_value(); + } +} + +// Add a package. + +Named_object* +Gogo::add_package(const std::string& real_name, const std::string& alias, + const std::string& unique_prefix, source_location location) +{ + gcc_assert(this->in_global_scope()); + + // Register the package. Note that we might have already seen it in + // an earlier import. + Package* package = this->register_package(real_name, unique_prefix, location); + + return this->package_->bindings()->add_package(alias, package); +} + +// Register a package. This package may or may not be imported. This +// returns the Package structure for the package, creating if it +// necessary. + +Package* +Gogo::register_package(const std::string& package_name, + const std::string& unique_prefix, + source_location location) +{ + gcc_assert(!unique_prefix.empty() && !package_name.empty()); + std::string name = unique_prefix + '.' + package_name; + Package* package = NULL; + std::pair<Packages::iterator, bool> ins = + this->packages_.insert(std::make_pair(name, package)); + if (!ins.second) + { + // We have seen this package name before. + package = ins.first->second; + gcc_assert(package != NULL); + gcc_assert(package->name() == package_name + && package->unique_prefix() == unique_prefix); + if (package->location() == UNKNOWN_LOCATION) + package->set_location(location); + } + else + { + // First time we have seen this package name. + package = new Package(package_name, unique_prefix, location); + gcc_assert(ins.first->second == NULL); + ins.first->second = package; + } + + return package; +} + +// Start compiling a function. + +Named_object* +Gogo::start_function(const std::string& name, Function_type* type, + bool add_method_to_type, source_location location) +{ + bool at_top_level = this->functions_.empty(); + + Block* block = new Block(NULL, location); + + Function* enclosing = (at_top_level + ? NULL + : this->functions_.back().function->func_value()); + + Function* function = new Function(type, enclosing, block, location); + + if (type->is_method()) + { + const Typed_identifier* receiver = type->receiver(); + Variable* this_param = new Variable(receiver->type(), NULL, false, + true, true, location); + std::string name = receiver->name(); + if (name.empty()) + { + // We need to give receivers a name since they wind up in + // DECL_ARGUMENTS. FIXME. + static unsigned int count; + char buf[50]; + snprintf(buf, sizeof buf, "r.%u", count); + ++count; + name = buf; + } + block->bindings()->add_variable(name, NULL, this_param); + } + + const Typed_identifier_list* parameters = type->parameters(); + bool is_varargs = type->is_varargs(); + if (parameters != NULL) + { + for (Typed_identifier_list::const_iterator p = parameters->begin(); + p != parameters->end(); + ++p) + { + Variable* param = new Variable(p->type(), NULL, false, true, false, + location); + if (is_varargs && p + 1 == parameters->end()) + param->set_is_varargs_parameter(); + + std::string name = p->name(); + if (name.empty() || Gogo::is_sink_name(name)) + { + // We need to give parameters a name since they wind up + // in DECL_ARGUMENTS. FIXME. + static unsigned int count; + char buf[50]; + snprintf(buf, sizeof buf, "p.%u", count); + ++count; + name = buf; + } + block->bindings()->add_variable(name, NULL, param); + } + } + + function->create_named_result_variables(this); + + const std::string* pname; + std::string nested_name; + bool is_init = false; + if (Gogo::unpack_hidden_name(name) == "init" && !type->is_method()) + { + if ((type->parameters() != NULL && !type->parameters()->empty()) + || (type->results() != NULL && !type->results()->empty())) + error_at(location, + "func init must have no arguments and no return values"); + // There can be multiple "init" functions, so give them each a + // different name. + static int init_count; + char buf[30]; + snprintf(buf, sizeof buf, ".$init%d", init_count); + ++init_count; + nested_name = buf; + pname = &nested_name; + is_init = true; + } + else if (!name.empty()) + pname = &name; + else + { + // Invent a name for a nested function. + static int nested_count; + char buf[30]; + snprintf(buf, sizeof buf, ".$nested%d", nested_count); + ++nested_count; + nested_name = buf; + pname = &nested_name; + } + + Named_object* ret; + if (Gogo::is_sink_name(*pname)) + { + static int sink_count; + char buf[30]; + snprintf(buf, sizeof buf, ".$sink%d", sink_count); + ++sink_count; + ret = Named_object::make_function(buf, NULL, function); + } + else if (!type->is_method()) + { + ret = this->package_->bindings()->add_function(*pname, NULL, function); + if (!ret->is_function() || ret->func_value() != function) + { + // Redefinition error. Invent a name to avoid knockon + // errors. + static int redefinition_count; + char buf[30]; + snprintf(buf, sizeof buf, ".$redefined%d", redefinition_count); + ++redefinition_count; + ret = this->package_->bindings()->add_function(buf, NULL, function); + } + } + else + { + if (!add_method_to_type) + ret = Named_object::make_function(name, NULL, function); + else + { + gcc_assert(at_top_level); + Type* rtype = type->receiver()->type(); + + // We want to look through the pointer created by the + // parser, without getting an error if the type is not yet + // defined. + if (rtype->classification() == Type::TYPE_POINTER) + rtype = rtype->points_to(); + + if (rtype->is_error_type()) + ret = Named_object::make_function(name, NULL, function); + else if (rtype->named_type() != NULL) + { + ret = rtype->named_type()->add_method(name, function); + if (!ret->is_function()) + { + // Redefinition error. + ret = Named_object::make_function(name, NULL, function); + } + } + else if (rtype->forward_declaration_type() != NULL) + { + Named_object* type_no = + rtype->forward_declaration_type()->named_object(); + if (type_no->is_unknown()) + { + // If we are seeing methods it really must be a + // type. Declare it as such. An alternative would + // be to support lists of methods for unknown + // expressions. Either way the error messages if + // this is not a type are going to get confusing. + Named_object* declared = + this->declare_package_type(type_no->name(), + type_no->location()); + gcc_assert(declared + == type_no->unknown_value()->real_named_object()); + } + ret = rtype->forward_declaration_type()->add_method(name, + function); + } + else + gcc_unreachable(); + } + this->package_->bindings()->add_method(ret); + } + + this->functions_.resize(this->functions_.size() + 1); + Open_function& of(this->functions_.back()); + of.function = ret; + of.blocks.push_back(block); + + if (is_init) + { + this->init_functions_.push_back(ret); + this->need_init_fn_ = true; + } + + return ret; +} + +// Finish compiling a function. + +void +Gogo::finish_function(source_location location) +{ + this->finish_block(location); + gcc_assert(this->functions_.back().blocks.empty()); + this->functions_.pop_back(); +} + +// Return the current function. + +Named_object* +Gogo::current_function() const +{ + gcc_assert(!this->functions_.empty()); + return this->functions_.back().function; +} + +// Start a new block. + +void +Gogo::start_block(source_location location) +{ + gcc_assert(!this->functions_.empty()); + Block* block = new Block(this->current_block(), location); + this->functions_.back().blocks.push_back(block); +} + +// Finish a block. + +Block* +Gogo::finish_block(source_location location) +{ + gcc_assert(!this->functions_.empty()); + gcc_assert(!this->functions_.back().blocks.empty()); + Block* block = this->functions_.back().blocks.back(); + this->functions_.back().blocks.pop_back(); + block->set_end_location(location); + return block; +} + +// Add an unknown name. + +Named_object* +Gogo::add_unknown_name(const std::string& name, source_location location) +{ + return this->package_->bindings()->add_unknown_name(name, location); +} + +// Declare a function. + +Named_object* +Gogo::declare_function(const std::string& name, Function_type* type, + source_location location) +{ + if (!type->is_method()) + return this->current_bindings()->add_function_declaration(name, NULL, type, + location); + else + { + // We don't bother to add this to the list of global + // declarations. + Type* rtype = type->receiver()->type(); + + // We want to look through the pointer created by the + // parser, without getting an error if the type is not yet + // defined. + if (rtype->classification() == Type::TYPE_POINTER) + rtype = rtype->points_to(); + + if (rtype->is_error_type()) + return NULL; + else if (rtype->named_type() != NULL) + return rtype->named_type()->add_method_declaration(name, NULL, type, + location); + else if (rtype->forward_declaration_type() != NULL) + { + Forward_declaration_type* ftype = rtype->forward_declaration_type(); + return ftype->add_method_declaration(name, type, location); + } + else + gcc_unreachable(); + } +} + +// Add a label definition. + +Label* +Gogo::add_label_definition(const std::string& label_name, + source_location location) +{ + gcc_assert(!this->functions_.empty()); + Function* func = this->functions_.back().function->func_value(); + Label* label = func->add_label_definition(label_name, location); + this->add_statement(Statement::make_label_statement(label, location)); + return label; +} + +// Add a label reference. + +Label* +Gogo::add_label_reference(const std::string& label_name) +{ + gcc_assert(!this->functions_.empty()); + Function* func = this->functions_.back().function->func_value(); + return func->add_label_reference(label_name); +} + +// Add a statement. + +void +Gogo::add_statement(Statement* statement) +{ + gcc_assert(!this->functions_.empty() + && !this->functions_.back().blocks.empty()); + this->functions_.back().blocks.back()->add_statement(statement); +} + +// Add a block. + +void +Gogo::add_block(Block* block, source_location location) +{ + gcc_assert(!this->functions_.empty() + && !this->functions_.back().blocks.empty()); + Statement* statement = Statement::make_block_statement(block, location); + this->functions_.back().blocks.back()->add_statement(statement); +} + +// Add a constant. + +Named_object* +Gogo::add_constant(const Typed_identifier& tid, Expression* expr, + int iota_value) +{ + return this->current_bindings()->add_constant(tid, NULL, expr, iota_value); +} + +// Add a type. + +void +Gogo::add_type(const std::string& name, Type* type, source_location location) +{ + Named_object* no = this->current_bindings()->add_type(name, NULL, type, + location); + if (!this->in_global_scope() && no->is_type()) + no->type_value()->set_in_function(this->functions_.back().function); +} + +// Add a named type. + +void +Gogo::add_named_type(Named_type* type) +{ + gcc_assert(this->in_global_scope()); + this->current_bindings()->add_named_type(type); +} + +// Declare a type. + +Named_object* +Gogo::declare_type(const std::string& name, source_location location) +{ + Bindings* bindings = this->current_bindings(); + Named_object* no = bindings->add_type_declaration(name, NULL, location); + if (!this->in_global_scope() && no->is_type_declaration()) + { + Named_object* f = this->functions_.back().function; + no->type_declaration_value()->set_in_function(f); + } + return no; +} + +// Declare a type at the package level. + +Named_object* +Gogo::declare_package_type(const std::string& name, source_location location) +{ + return this->package_->bindings()->add_type_declaration(name, NULL, location); +} + +// Define a type which was already declared. + +void +Gogo::define_type(Named_object* no, Named_type* type) +{ + this->current_bindings()->define_type(no, type); +} + +// Add a variable. + +Named_object* +Gogo::add_variable(const std::string& name, Variable* variable) +{ + Named_object* no = this->current_bindings()->add_variable(name, NULL, + variable); + + // In a function the middle-end wants to see a DECL_EXPR node. + if (no != NULL + && no->is_variable() + && !no->var_value()->is_parameter() + && !this->functions_.empty()) + this->add_statement(Statement::make_variable_declaration(no)); + + return no; +} + +// Add a sink--a reference to the blank identifier _. + +Named_object* +Gogo::add_sink() +{ + return Named_object::make_sink(); +} + +// Add a named object. + +void +Gogo::add_named_object(Named_object* no) +{ + this->current_bindings()->add_named_object(no); +} + +// Record that we've seen an interface type. + +void +Gogo::record_interface_type(Interface_type* itype) +{ + this->interface_types_.push_back(itype); +} + +// Return a name for a thunk object. + +std::string +Gogo::thunk_name() +{ + static int thunk_count; + char thunk_name[50]; + snprintf(thunk_name, sizeof thunk_name, "$thunk%d", thunk_count); + ++thunk_count; + return thunk_name; +} + +// Return whether a function is a thunk. + +bool +Gogo::is_thunk(const Named_object* no) +{ + return no->name().compare(0, 6, "$thunk") == 0; +} + +// Define the global names. We do this only after parsing all the +// input files, because the program might define the global names +// itself. + +void +Gogo::define_global_names() +{ + for (Bindings::const_declarations_iterator p = + this->globals_->begin_declarations(); + p != this->globals_->end_declarations(); + ++p) + { + Named_object* global_no = p->second; + std::string name(Gogo::pack_hidden_name(global_no->name(), false)); + Named_object* no = this->package_->bindings()->lookup(name); + if (no == NULL) + continue; + no = no->resolve(); + if (no->is_type_declaration()) + { + if (global_no->is_type()) + { + if (no->type_declaration_value()->has_methods()) + error_at(no->location(), + "may not define methods for global type"); + no->set_type_value(global_no->type_value()); + } + else + { + error_at(no->location(), "expected type"); + Type* errtype = Type::make_error_type(); + Named_object* err = Named_object::make_type("error", NULL, + errtype, + BUILTINS_LOCATION); + no->set_type_value(err->type_value()); + } + } + else if (no->is_unknown()) + no->unknown_value()->set_real_named_object(global_no); + } +} + +// Clear out names in file scope. + +void +Gogo::clear_file_scope() +{ + this->package_->bindings()->clear_file_scope(); + + // Warn about packages which were imported but not used. + for (Packages::iterator p = this->packages_.begin(); + p != this->packages_.end(); + ++p) + { + Package* package = p->second; + if (package != this->package_ + && package->is_imported() + && !package->used() + && !package->uses_sink_alias() + && !saw_errors()) + error_at(package->location(), "imported and not used: %s", + Gogo::message_name(package->name()).c_str()); + package->clear_is_imported(); + package->clear_uses_sink_alias(); + package->clear_used(); + } +} + +// Traverse the tree. + +void +Gogo::traverse(Traverse* traverse) +{ + // Traverse the current package first for consistency. The other + // packages will only contain imported types, constants, and + // declarations. + if (this->package_->bindings()->traverse(traverse, true) == TRAVERSE_EXIT) + return; + for (Packages::const_iterator p = this->packages_.begin(); + p != this->packages_.end(); + ++p) + { + if (p->second != this->package_) + { + if (p->second->bindings()->traverse(traverse, true) == TRAVERSE_EXIT) + break; + } + } +} + +// Traversal class used to verify types. + +class Verify_types : public Traverse +{ + public: + Verify_types() + : Traverse(traverse_types) + { } + + int + type(Type*); +}; + +// Verify that a type is correct. + +int +Verify_types::type(Type* t) +{ + if (!t->verify()) + return TRAVERSE_SKIP_COMPONENTS; + return TRAVERSE_CONTINUE; +} + +// Verify that all types are correct. + +void +Gogo::verify_types() +{ + Verify_types traverse; + this->traverse(&traverse); +} + +// Traversal class used to lower parse tree. + +class Lower_parse_tree : public Traverse +{ + public: + Lower_parse_tree(Gogo* gogo, Named_object* function) + : Traverse(traverse_variables + | traverse_constants + | traverse_functions + | traverse_statements + | traverse_expressions), + gogo_(gogo), function_(function), iota_value_(-1) + { } + + int + variable(Named_object*); + + int + constant(Named_object*, bool); + + int + function(Named_object*); + + int + statement(Block*, size_t* pindex, Statement*); + + int + expression(Expression**); + + private: + // General IR. + Gogo* gogo_; + // The function we are traversing. + Named_object* function_; + // Value to use for the predeclared constant iota. + int iota_value_; +}; + +// Lower variables. We handle variables specially to break loops in +// which a variable initialization expression refers to itself. The +// loop breaking is in lower_init_expression. + +int +Lower_parse_tree::variable(Named_object* no) +{ + if (no->is_variable()) + no->var_value()->lower_init_expression(this->gogo_, this->function_); + return TRAVERSE_CONTINUE; +} + +// Lower constants. We handle constants specially so that we can set +// the right value for the predeclared constant iota. This works in +// conjunction with the way we lower Const_expression objects. + +int +Lower_parse_tree::constant(Named_object* no, bool) +{ + Named_constant* nc = no->const_value(); + + // Don't get into trouble if the constant's initializer expression + // refers to the constant itself. + if (nc->lowering()) + return TRAVERSE_CONTINUE; + nc->set_lowering(); + + gcc_assert(this->iota_value_ == -1); + this->iota_value_ = nc->iota_value(); + nc->traverse_expression(this); + this->iota_value_ = -1; + + nc->clear_lowering(); + + // We will traverse the expression a second time, but that will be + // fast. + + return TRAVERSE_CONTINUE; +} + +// Lower function closure types. Record the function while lowering +// it, so that we can pass it down when lowering an expression. + +int +Lower_parse_tree::function(Named_object* no) +{ + no->func_value()->set_closure_type(); + + gcc_assert(this->function_ == NULL); + this->function_ = no; + int t = no->func_value()->traverse(this); + this->function_ = NULL; + + if (t == TRAVERSE_EXIT) + return t; + return TRAVERSE_SKIP_COMPONENTS; +} + +// Lower statement parse trees. + +int +Lower_parse_tree::statement(Block* block, size_t* pindex, Statement* sorig) +{ + // Lower the expressions first. + int t = sorig->traverse_contents(this); + if (t == TRAVERSE_EXIT) + return t; + + // Keep lowering until nothing changes. + Statement* s = sorig; + while (true) + { + Statement* snew = s->lower(this->gogo_, block); + if (snew == s) + break; + s = snew; + t = s->traverse_contents(this); + if (t == TRAVERSE_EXIT) + return t; + } + + if (s != sorig) + block->replace_statement(*pindex, s); + + return TRAVERSE_SKIP_COMPONENTS; +} + +// Lower expression parse trees. + +int +Lower_parse_tree::expression(Expression** pexpr) +{ + // We have to lower all subexpressions first, so that we can get + // their type if necessary. This is awkward, because we don't have + // a postorder traversal pass. + if ((*pexpr)->traverse_subexpressions(this) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + // Keep lowering until nothing changes. + while (true) + { + Expression* e = *pexpr; + Expression* enew = e->lower(this->gogo_, this->function_, + this->iota_value_); + if (enew == e) + break; + *pexpr = enew; + } + return TRAVERSE_SKIP_COMPONENTS; +} + +// Lower the parse tree. This is called after the parse is complete, +// when all names should be resolved. + +void +Gogo::lower_parse_tree() +{ + Lower_parse_tree lower_parse_tree(this, NULL); + this->traverse(&lower_parse_tree); +} + +// Lower an expression. + +void +Gogo::lower_expression(Named_object* function, Expression** pexpr) +{ + Lower_parse_tree lower_parse_tree(this, function); + lower_parse_tree.expression(pexpr); +} + +// Lower a constant. This is called when lowering a reference to a +// constant. We have to make sure that the constant has already been +// lowered. + +void +Gogo::lower_constant(Named_object* no) +{ + gcc_assert(no->is_const()); + Lower_parse_tree lower(this, NULL); + lower.constant(no, false); +} + +// Look for interface types to finalize methods of inherited +// interfaces. + +class Finalize_methods : public Traverse +{ + public: + Finalize_methods(Gogo* gogo) + : Traverse(traverse_types), + gogo_(gogo) + { } + + int + type(Type*); + + private: + Gogo* gogo_; +}; + +// Finalize the methods of an interface type. + +int +Finalize_methods::type(Type* t) +{ + // Check the classification so that we don't finalize the methods + // twice for a named interface type. + switch (t->classification()) + { + case Type::TYPE_INTERFACE: + t->interface_type()->finalize_methods(); + break; + + case Type::TYPE_NAMED: + { + // We have to finalize the methods of the real type first. + // But if the real type is a struct type, then we only want to + // finalize the methods of the field types, not of the struct + // type itself. We don't want to add methods to the struct, + // since it has a name. + Type* rt = t->named_type()->real_type(); + if (rt->classification() != Type::TYPE_STRUCT) + { + if (Type::traverse(rt, this) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + else + { + if (rt->struct_type()->traverse_field_types(this) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + + t->named_type()->finalize_methods(this->gogo_); + + return TRAVERSE_SKIP_COMPONENTS; + } + + case Type::TYPE_STRUCT: + t->struct_type()->finalize_methods(this->gogo_); + break; + + default: + break; + } + + return TRAVERSE_CONTINUE; +} + +// Finalize method lists and build stub methods for types. + +void +Gogo::finalize_methods() +{ + Finalize_methods finalize(this); + this->traverse(&finalize); +} + +// Set types for unspecified variables and constants. + +void +Gogo::determine_types() +{ + Bindings* bindings = this->current_bindings(); + for (Bindings::const_definitions_iterator p = bindings->begin_definitions(); + p != bindings->end_definitions(); + ++p) + { + if ((*p)->is_function()) + (*p)->func_value()->determine_types(); + else if ((*p)->is_variable()) + (*p)->var_value()->determine_type(); + else if ((*p)->is_const()) + (*p)->const_value()->determine_type(); + + // See if a variable requires us to build an initialization + // function. We know that we will see all global variables + // here. + if (!this->need_init_fn_ && (*p)->is_variable()) + { + Variable* variable = (*p)->var_value(); + + // If this is a global variable which requires runtime + // initialization, we need an initialization function. + if (!variable->is_global()) + ; + else if (variable->init() == NULL) + ; + else if (variable->type()->interface_type() != NULL) + this->need_init_fn_ = true; + else if (variable->init()->is_constant()) + ; + else if (!variable->init()->is_composite_literal()) + this->need_init_fn_ = true; + else if (variable->init()->is_nonconstant_composite_literal()) + this->need_init_fn_ = true; + + // If this is a global variable which holds a pointer value, + // then we need an initialization function to register it as a + // GC root. + if (variable->is_global() && variable->type()->has_pointer()) + this->need_init_fn_ = true; + } + } + + // Determine the types of constants in packages. + for (Packages::const_iterator p = this->packages_.begin(); + p != this->packages_.end(); + ++p) + p->second->determine_types(); +} + +// Traversal class used for type checking. + +class Check_types_traverse : public Traverse +{ + public: + Check_types_traverse(Gogo* gogo) + : Traverse(traverse_variables + | traverse_constants + | traverse_statements + | traverse_expressions), + gogo_(gogo) + { } + + int + variable(Named_object*); + + int + constant(Named_object*, bool); + + int + statement(Block*, size_t* pindex, Statement*); + + int + expression(Expression**); + + private: + // General IR. + Gogo* gogo_; +}; + +// Check that a variable initializer has the right type. + +int +Check_types_traverse::variable(Named_object* named_object) +{ + if (named_object->is_variable()) + { + Variable* var = named_object->var_value(); + Expression* init = var->init(); + std::string reason; + if (init != NULL + && !Type::are_assignable(var->type(), init->type(), &reason)) + { + if (reason.empty()) + error_at(var->location(), "incompatible type in initialization"); + else + error_at(var->location(), + "incompatible type in initialization (%s)", + reason.c_str()); + var->clear_init(); + } + } + return TRAVERSE_CONTINUE; +} + +// Check that a constant initializer has the right type. + +int +Check_types_traverse::constant(Named_object* named_object, bool) +{ + Named_constant* constant = named_object->const_value(); + Type* ctype = constant->type(); + if (ctype->integer_type() == NULL + && ctype->float_type() == NULL + && ctype->complex_type() == NULL + && !ctype->is_boolean_type() + && !ctype->is_string_type()) + { + if (!ctype->is_error_type()) + error_at(constant->location(), "invalid constant type"); + constant->set_error(); + } + else if (!constant->expr()->is_constant()) + { + error_at(constant->expr()->location(), "expression is not constant"); + constant->set_error(); + } + else if (!Type::are_assignable(constant->type(), constant->expr()->type(), + NULL)) + { + error_at(constant->location(), + "initialization expression has wrong type"); + constant->set_error(); + } + return TRAVERSE_CONTINUE; +} + +// Check that types are valid in a statement. + +int +Check_types_traverse::statement(Block*, size_t*, Statement* s) +{ + s->check_types(this->gogo_); + return TRAVERSE_CONTINUE; +} + +// Check that types are valid in an expression. + +int +Check_types_traverse::expression(Expression** expr) +{ + (*expr)->check_types(this->gogo_); + return TRAVERSE_CONTINUE; +} + +// Check that types are valid. + +void +Gogo::check_types() +{ + Check_types_traverse traverse(this); + this->traverse(&traverse); +} + +// Check the types in a single block. + +void +Gogo::check_types_in_block(Block* block) +{ + Check_types_traverse traverse(this); + block->traverse(&traverse); +} + +// A traversal class used to find a single shortcut operator within an +// expression. + +class Find_shortcut : public Traverse +{ + public: + Find_shortcut() + : Traverse(traverse_blocks + | traverse_statements + | traverse_expressions), + found_(NULL) + { } + + // A pointer to the expression which was found, or NULL if none was + // found. + Expression** + found() const + { return this->found_; } + + protected: + int + block(Block*) + { return TRAVERSE_SKIP_COMPONENTS; } + + int + statement(Block*, size_t*, Statement*) + { return TRAVERSE_SKIP_COMPONENTS; } + + int + expression(Expression**); + + private: + Expression** found_; +}; + +// Find a shortcut expression. + +int +Find_shortcut::expression(Expression** pexpr) +{ + Expression* expr = *pexpr; + Binary_expression* be = expr->binary_expression(); + if (be == NULL) + return TRAVERSE_CONTINUE; + Operator op = be->op(); + if (op != OPERATOR_OROR && op != OPERATOR_ANDAND) + return TRAVERSE_CONTINUE; + gcc_assert(this->found_ == NULL); + this->found_ = pexpr; + return TRAVERSE_EXIT; +} + +// A traversal class used to turn shortcut operators into explicit if +// statements. + +class Shortcuts : public Traverse +{ + public: + Shortcuts(Gogo* gogo) + : Traverse(traverse_variables + | traverse_statements), + gogo_(gogo) + { } + + protected: + int + variable(Named_object*); + + int + statement(Block*, size_t*, Statement*); + + private: + // Convert a shortcut operator. + Statement* + convert_shortcut(Block* enclosing, Expression** pshortcut); + + // The IR. + Gogo* gogo_; +}; + +// Remove shortcut operators in a single statement. + +int +Shortcuts::statement(Block* block, size_t* pindex, Statement* s) +{ + // FIXME: This approach doesn't work for switch statements, because + // we add the new statements before the whole switch when we need to + // instead add them just before the switch expression. The right + // fix is probably to lower switch statements with nonconstant cases + // to a series of conditionals. + if (s->switch_statement() != NULL) + return TRAVERSE_CONTINUE; + + while (true) + { + Find_shortcut find_shortcut; + + // If S is a variable declaration, then ordinary traversal won't + // do anything. We want to explicitly traverse the + // initialization expression if there is one. + Variable_declaration_statement* vds = s->variable_declaration_statement(); + Expression* init = NULL; + if (vds == NULL) + s->traverse_contents(&find_shortcut); + else + { + init = vds->var()->var_value()->init(); + if (init == NULL) + return TRAVERSE_CONTINUE; + init->traverse(&init, &find_shortcut); + } + Expression** pshortcut = find_shortcut.found(); + if (pshortcut == NULL) + return TRAVERSE_CONTINUE; + + Statement* snew = this->convert_shortcut(block, pshortcut); + block->insert_statement_before(*pindex, snew); + ++*pindex; + + if (pshortcut == &init) + vds->var()->var_value()->set_init(init); + } +} + +// Remove shortcut operators in the initializer of a global variable. + +int +Shortcuts::variable(Named_object* no) +{ + if (no->is_result_variable()) + return TRAVERSE_CONTINUE; + Variable* var = no->var_value(); + Expression* init = var->init(); + if (!var->is_global() || init == NULL) + return TRAVERSE_CONTINUE; + + while (true) + { + Find_shortcut find_shortcut; + init->traverse(&init, &find_shortcut); + Expression** pshortcut = find_shortcut.found(); + if (pshortcut == NULL) + return TRAVERSE_CONTINUE; + + Statement* snew = this->convert_shortcut(NULL, pshortcut); + var->add_preinit_statement(this->gogo_, snew); + if (pshortcut == &init) + var->set_init(init); + } +} + +// Given an expression which uses a shortcut operator, return a +// statement which implements it, and update *PSHORTCUT accordingly. + +Statement* +Shortcuts::convert_shortcut(Block* enclosing, Expression** pshortcut) +{ + Binary_expression* shortcut = (*pshortcut)->binary_expression(); + Expression* left = shortcut->left(); + Expression* right = shortcut->right(); + source_location loc = shortcut->location(); + + Block* retblock = new Block(enclosing, loc); + retblock->set_end_location(loc); + + Temporary_statement* ts = Statement::make_temporary(Type::lookup_bool_type(), + left, loc); + retblock->add_statement(ts); + + Block* block = new Block(retblock, loc); + block->set_end_location(loc); + Expression* tmpref = Expression::make_temporary_reference(ts, loc); + Statement* assign = Statement::make_assignment(tmpref, right, loc); + block->add_statement(assign); + + Expression* cond = Expression::make_temporary_reference(ts, loc); + if (shortcut->binary_expression()->op() == OPERATOR_OROR) + cond = Expression::make_unary(OPERATOR_NOT, cond, loc); + + Statement* if_statement = Statement::make_if_statement(cond, block, NULL, + loc); + retblock->add_statement(if_statement); + + *pshortcut = Expression::make_temporary_reference(ts, loc); + + delete shortcut; + + // Now convert any shortcut operators in LEFT and RIGHT. + Shortcuts shortcuts(this->gogo_); + retblock->traverse(&shortcuts); + + return Statement::make_block_statement(retblock, loc); +} + +// Turn shortcut operators into explicit if statements. Doing this +// considerably simplifies the order of evaluation rules. + +void +Gogo::remove_shortcuts() +{ + Shortcuts shortcuts(this); + this->traverse(&shortcuts); +} + +// A traversal class which finds all the expressions which must be +// evaluated in order within a statement or larger expression. This +// is used to implement the rules about order of evaluation. + +class Find_eval_ordering : public Traverse +{ + private: + typedef std::vector<Expression**> Expression_pointers; + + public: + Find_eval_ordering() + : Traverse(traverse_blocks + | traverse_statements + | traverse_expressions), + exprs_() + { } + + size_t + size() const + { return this->exprs_.size(); } + + typedef Expression_pointers::const_iterator const_iterator; + + const_iterator + begin() const + { return this->exprs_.begin(); } + + const_iterator + end() const + { return this->exprs_.end(); } + + protected: + int + block(Block*) + { return TRAVERSE_SKIP_COMPONENTS; } + + int + statement(Block*, size_t*, Statement*) + { return TRAVERSE_SKIP_COMPONENTS; } + + int + expression(Expression**); + + private: + // A list of pointers to expressions with side-effects. + Expression_pointers exprs_; +}; + +// If an expression must be evaluated in order, put it on the list. + +int +Find_eval_ordering::expression(Expression** expression_pointer) +{ + // We have to look at subexpressions before this one. + if ((*expression_pointer)->traverse_subexpressions(this) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if ((*expression_pointer)->must_eval_in_order()) + this->exprs_.push_back(expression_pointer); + return TRAVERSE_SKIP_COMPONENTS; +} + +// A traversal class for ordering evaluations. + +class Order_eval : public Traverse +{ + public: + Order_eval(Gogo* gogo) + : Traverse(traverse_variables + | traverse_statements), + gogo_(gogo) + { } + + int + variable(Named_object*); + + int + statement(Block*, size_t*, Statement*); + + private: + // The IR. + Gogo* gogo_; +}; + +// Implement the order of evaluation rules for a statement. + +int +Order_eval::statement(Block* block, size_t* pindex, Statement* s) +{ + // FIXME: This approach doesn't work for switch statements, because + // we add the new statements before the whole switch when we need to + // instead add them just before the switch expression. The right + // fix is probably to lower switch statements with nonconstant cases + // to a series of conditionals. + if (s->switch_statement() != NULL) + return TRAVERSE_CONTINUE; + + Find_eval_ordering find_eval_ordering; + + // If S is a variable declaration, then ordinary traversal won't do + // anything. We want to explicitly traverse the initialization + // expression if there is one. + Variable_declaration_statement* vds = s->variable_declaration_statement(); + Expression* init = NULL; + Expression* orig_init = NULL; + if (vds == NULL) + s->traverse_contents(&find_eval_ordering); + else + { + init = vds->var()->var_value()->init(); + if (init == NULL) + return TRAVERSE_CONTINUE; + orig_init = init; + + // It might seem that this could be + // init->traverse_subexpressions. Unfortunately that can fail + // in a case like + // var err os.Error + // newvar, err := call(arg()) + // Here newvar will have an init of call result 0 of + // call(arg()). If we only traverse subexpressions, we will + // only find arg(), and we won't bother to move anything out. + // Then we get to the assignment to err, we will traverse the + // whole statement, and this time we will find both call() and + // arg(), and so we will move them out. This will cause them to + // be put into temporary variables before the assignment to err + // but after the declaration of newvar. To avoid that problem, + // we traverse the entire expression here. + Expression::traverse(&init, &find_eval_ordering); + } + + if (find_eval_ordering.size() <= 1) + { + // If there is only one expression with a side-effect, we can + // leave it in place. + return TRAVERSE_CONTINUE; + } + + bool is_thunk = s->thunk_statement() != NULL; + for (Find_eval_ordering::const_iterator p = find_eval_ordering.begin(); + p != find_eval_ordering.end(); + ++p) + { + Expression** pexpr = *p; + + // If the last expression is a send or receive expression, we + // may be ignoring the value; we don't want to evaluate it + // early. + if (p + 1 == find_eval_ordering.end() + && ((*pexpr)->classification() == Expression::EXPRESSION_SEND + || (*pexpr)->classification() == Expression::EXPRESSION_RECEIVE)) + break; + + // The last expression in a thunk will be the call passed to go + // or defer, which we must not evaluate early. + if (is_thunk && p + 1 == find_eval_ordering.end()) + break; + + source_location loc = (*pexpr)->location(); + Temporary_statement* ts = Statement::make_temporary(NULL, *pexpr, loc); + block->insert_statement_before(*pindex, ts); + ++*pindex; + + *pexpr = Expression::make_temporary_reference(ts, loc); + } + + if (init != orig_init) + vds->var()->var_value()->set_init(init); + + return TRAVERSE_CONTINUE; +} + +// Implement the order of evaluation rules for the initializer of a +// global variable. + +int +Order_eval::variable(Named_object* no) +{ + if (no->is_result_variable()) + return TRAVERSE_CONTINUE; + Variable* var = no->var_value(); + Expression* init = var->init(); + if (!var->is_global() || init == NULL) + return TRAVERSE_CONTINUE; + + Find_eval_ordering find_eval_ordering; + init->traverse_subexpressions(&find_eval_ordering); + + if (find_eval_ordering.size() <= 1) + { + // If there is only one expression with a side-effect, we can + // leave it in place. + return TRAVERSE_SKIP_COMPONENTS; + } + + for (Find_eval_ordering::const_iterator p = find_eval_ordering.begin(); + p != find_eval_ordering.end(); + ++p) + { + Expression** pexpr = *p; + source_location loc = (*pexpr)->location(); + Temporary_statement* ts = Statement::make_temporary(NULL, *pexpr, loc); + var->add_preinit_statement(this->gogo_, ts); + *pexpr = Expression::make_temporary_reference(ts, loc); + } + + return TRAVERSE_SKIP_COMPONENTS; +} + +// Use temporary variables to implement the order of evaluation rules. + +void +Gogo::order_evaluations() +{ + Order_eval order_eval(this); + this->traverse(&order_eval); +} + +// Traversal to convert calls to the predeclared recover function to +// pass in an argument indicating whether it can recover from a panic +// or not. + +class Convert_recover : public Traverse +{ + public: + Convert_recover(Named_object* arg) + : Traverse(traverse_expressions), + arg_(arg) + { } + + protected: + int + expression(Expression**); + + private: + // The argument to pass to the function. + Named_object* arg_; +}; + +// Convert calls to recover. + +int +Convert_recover::expression(Expression** pp) +{ + Call_expression* ce = (*pp)->call_expression(); + if (ce != NULL && ce->is_recover_call()) + ce->set_recover_arg(Expression::make_var_reference(this->arg_, + ce->location())); + return TRAVERSE_CONTINUE; +} + +// Traversal for build_recover_thunks. + +class Build_recover_thunks : public Traverse +{ + public: + Build_recover_thunks(Gogo* gogo) + : Traverse(traverse_functions), + gogo_(gogo) + { } + + int + function(Named_object*); + + private: + Expression* + can_recover_arg(source_location); + + // General IR. + Gogo* gogo_; +}; + +// If this function calls recover, turn it into a thunk. + +int +Build_recover_thunks::function(Named_object* orig_no) +{ + Function* orig_func = orig_no->func_value(); + if (!orig_func->calls_recover() + || orig_func->is_recover_thunk() + || orig_func->has_recover_thunk()) + return TRAVERSE_CONTINUE; + + Gogo* gogo = this->gogo_; + source_location location = orig_func->location(); + + static int count; + char buf[50]; + + Function_type* orig_fntype = orig_func->type(); + Typed_identifier_list* new_params = new Typed_identifier_list(); + std::string receiver_name; + if (orig_fntype->is_method()) + { + const Typed_identifier* receiver = orig_fntype->receiver(); + snprintf(buf, sizeof buf, "rt.%u", count); + ++count; + receiver_name = buf; + new_params->push_back(Typed_identifier(receiver_name, receiver->type(), + receiver->location())); + } + const Typed_identifier_list* orig_params = orig_fntype->parameters(); + if (orig_params != NULL && !orig_params->empty()) + { + for (Typed_identifier_list::const_iterator p = orig_params->begin(); + p != orig_params->end(); + ++p) + { + snprintf(buf, sizeof buf, "pt.%u", count); + ++count; + new_params->push_back(Typed_identifier(buf, p->type(), + p->location())); + } + } + snprintf(buf, sizeof buf, "pr.%u", count); + ++count; + std::string can_recover_name = buf; + new_params->push_back(Typed_identifier(can_recover_name, + Type::lookup_bool_type(), + orig_fntype->location())); + + const Typed_identifier_list* orig_results = orig_fntype->results(); + Typed_identifier_list* new_results; + if (orig_results == NULL || orig_results->empty()) + new_results = NULL; + else + { + new_results = new Typed_identifier_list(); + for (Typed_identifier_list::const_iterator p = orig_results->begin(); + p != orig_results->end(); + ++p) + new_results->push_back(Typed_identifier("", p->type(), p->location())); + } + + Function_type *new_fntype = Type::make_function_type(NULL, new_params, + new_results, + orig_fntype->location()); + if (orig_fntype->is_varargs()) + new_fntype->set_is_varargs(); + + std::string name = orig_no->name() + "$recover"; + Named_object *new_no = gogo->start_function(name, new_fntype, false, + location); + Function *new_func = new_no->func_value(); + if (orig_func->enclosing() != NULL) + new_func->set_enclosing(orig_func->enclosing()); + + // We build the code for the original function attached to the new + // function, and then swap the original and new function bodies. + // This means that existing references to the original function will + // then refer to the new function. That makes this code a little + // confusing, in that the reference to NEW_NO really refers to the + // other function, not the one we are building. + + Expression* closure = NULL; + if (orig_func->needs_closure()) + { + Named_object* orig_closure_no = orig_func->closure_var(); + Variable* orig_closure_var = orig_closure_no->var_value(); + Variable* new_var = new Variable(orig_closure_var->type(), NULL, false, + true, false, location); + snprintf(buf, sizeof buf, "closure.%u", count); + ++count; + Named_object* new_closure_no = Named_object::make_variable(buf, NULL, + new_var); + new_func->set_closure_var(new_closure_no); + closure = Expression::make_var_reference(new_closure_no, location); + } + + Expression* fn = Expression::make_func_reference(new_no, closure, location); + + Expression_list* args = new Expression_list(); + if (new_params != NULL) + { + // Note that we skip the last parameter, which is the boolean + // indicating whether recover can succed. + for (Typed_identifier_list::const_iterator p = new_params->begin(); + p + 1 != new_params->end(); + ++p) + { + Named_object* p_no = gogo->lookup(p->name(), NULL); + gcc_assert(p_no != NULL + && p_no->is_variable() + && p_no->var_value()->is_parameter()); + args->push_back(Expression::make_var_reference(p_no, location)); + } + } + args->push_back(this->can_recover_arg(location)); + + Call_expression* call = Expression::make_call(fn, args, false, location); + + Statement* s; + if (orig_fntype->results() == NULL || orig_fntype->results()->empty()) + s = Statement::make_statement(call); + else + { + Expression_list* vals = new Expression_list(); + size_t rc = orig_fntype->results()->size(); + if (rc == 1) + vals->push_back(call); + else + { + for (size_t i = 0; i < rc; ++i) + vals->push_back(Expression::make_call_result(call, i)); + } + s = Statement::make_return_statement(new_func->type()->results(), + vals, location); + } + s->determine_types(); + gogo->add_statement(s); + + gogo->finish_function(location); + + // Swap the function bodies and types. + new_func->swap_for_recover(orig_func); + orig_func->set_is_recover_thunk(); + new_func->set_calls_recover(); + new_func->set_has_recover_thunk(); + + Bindings* orig_bindings = orig_func->block()->bindings(); + Bindings* new_bindings = new_func->block()->bindings(); + if (orig_fntype->is_method()) + { + // We changed the receiver to be a regular parameter. We have + // to update the binding accordingly in both functions. + Named_object* orig_rec_no = orig_bindings->lookup_local(receiver_name); + gcc_assert(orig_rec_no != NULL + && orig_rec_no->is_variable() + && !orig_rec_no->var_value()->is_receiver()); + orig_rec_no->var_value()->set_is_receiver(); + + const std::string& new_receiver_name(orig_fntype->receiver()->name()); + Named_object* new_rec_no = new_bindings->lookup_local(new_receiver_name); + if (new_rec_no == NULL) + gcc_assert(saw_errors()); + else + { + gcc_assert(new_rec_no->is_variable() + && new_rec_no->var_value()->is_receiver()); + new_rec_no->var_value()->set_is_not_receiver(); + } + } + + // Because we flipped blocks but not types, the can_recover + // parameter appears in the (now) old bindings as a parameter. + // Change it to a local variable, whereupon it will be discarded. + Named_object* can_recover_no = orig_bindings->lookup_local(can_recover_name); + gcc_assert(can_recover_no != NULL + && can_recover_no->is_variable() + && can_recover_no->var_value()->is_parameter()); + orig_bindings->remove_binding(can_recover_no); + + // Add the can_recover argument to the (now) new bindings, and + // attach it to any recover statements. + Variable* can_recover_var = new Variable(Type::lookup_bool_type(), NULL, + false, true, false, location); + can_recover_no = new_bindings->add_variable(can_recover_name, NULL, + can_recover_var); + Convert_recover convert_recover(can_recover_no); + new_func->traverse(&convert_recover); + + // Update the function pointers in any named results. + new_func->update_named_result_variables(); + orig_func->update_named_result_variables(); + + return TRAVERSE_CONTINUE; +} + +// Return the expression to pass for the .can_recover parameter to the +// new function. This indicates whether a call to recover may return +// non-nil. The expression is +// __go_can_recover(__builtin_return_address()). + +Expression* +Build_recover_thunks::can_recover_arg(source_location location) +{ + static Named_object* builtin_return_address; + if (builtin_return_address == NULL) + { + const source_location bloc = BUILTINS_LOCATION; + + Typed_identifier_list* param_types = new Typed_identifier_list(); + Type* uint_type = Type::lookup_integer_type("uint"); + param_types->push_back(Typed_identifier("l", uint_type, bloc)); + + Typed_identifier_list* return_types = new Typed_identifier_list(); + Type* voidptr_type = Type::make_pointer_type(Type::make_void_type()); + return_types->push_back(Typed_identifier("", voidptr_type, bloc)); + + Function_type* fntype = Type::make_function_type(NULL, param_types, + return_types, bloc); + builtin_return_address = + Named_object::make_function_declaration("__builtin_return_address", + NULL, fntype, bloc); + const char* n = "__builtin_return_address"; + builtin_return_address->func_declaration_value()->set_asm_name(n); + } + + static Named_object* can_recover; + if (can_recover == NULL) + { + const source_location bloc = BUILTINS_LOCATION; + Typed_identifier_list* param_types = new Typed_identifier_list(); + Type* voidptr_type = Type::make_pointer_type(Type::make_void_type()); + param_types->push_back(Typed_identifier("a", voidptr_type, bloc)); + Type* boolean_type = Type::lookup_bool_type(); + Typed_identifier_list* results = new Typed_identifier_list(); + results->push_back(Typed_identifier("", boolean_type, bloc)); + Function_type* fntype = Type::make_function_type(NULL, param_types, + results, bloc); + can_recover = Named_object::make_function_declaration("__go_can_recover", + NULL, fntype, + bloc); + can_recover->func_declaration_value()->set_asm_name("__go_can_recover"); + } + + Expression* fn = Expression::make_func_reference(builtin_return_address, + NULL, location); + + mpz_t zval; + mpz_init_set_ui(zval, 0UL); + Expression* zexpr = Expression::make_integer(&zval, NULL, location); + mpz_clear(zval); + Expression_list *args = new Expression_list(); + args->push_back(zexpr); + + Expression* call = Expression::make_call(fn, args, false, location); + + args = new Expression_list(); + args->push_back(call); + + fn = Expression::make_func_reference(can_recover, NULL, location); + return Expression::make_call(fn, args, false, location); +} + +// Build thunks for functions which call recover. We build a new +// function with an extra parameter, which is whether a call to +// recover can succeed. We then move the body of this function to +// that one. We then turn this function into a thunk which calls the +// new one, passing the value of +// __go_can_recover(__builtin_return_address()). The function will be +// marked as not splitting the stack. This will cooperate with the +// implementation of defer to make recover do the right thing. + +void +Gogo::build_recover_thunks() +{ + Build_recover_thunks build_recover_thunks(this); + this->traverse(&build_recover_thunks); +} + +// Look for named types to see whether we need to create an interface +// method table. + +class Build_method_tables : public Traverse +{ + public: + Build_method_tables(Gogo* gogo, + const std::vector<Interface_type*>& interfaces) + : Traverse(traverse_types), + gogo_(gogo), interfaces_(interfaces) + { } + + int + type(Type*); + + private: + // The IR. + Gogo* gogo_; + // A list of locally defined interfaces which have hidden methods. + const std::vector<Interface_type*>& interfaces_; +}; + +// Build all required interface method tables for types. We need to +// ensure that we have an interface method table for every interface +// which has a hidden method, for every named type which implements +// that interface. Normally we can just build interface method tables +// as we need them. However, in some cases we can require an +// interface method table for an interface defined in a different +// package for a type defined in that package. If that interface and +// type both use a hidden method, that is OK. However, we will not be +// able to build that interface method table when we need it, because +// the type's hidden method will be static. So we have to build it +// here, and just refer it from other packages as needed. + +void +Gogo::build_interface_method_tables() +{ + std::vector<Interface_type*> hidden_interfaces; + hidden_interfaces.reserve(this->interface_types_.size()); + for (std::vector<Interface_type*>::const_iterator pi = + this->interface_types_.begin(); + pi != this->interface_types_.end(); + ++pi) + { + const Typed_identifier_list* methods = (*pi)->methods(); + if (methods == NULL) + continue; + for (Typed_identifier_list::const_iterator pm = methods->begin(); + pm != methods->end(); + ++pm) + { + if (Gogo::is_hidden_name(pm->name())) + { + hidden_interfaces.push_back(*pi); + break; + } + } + } + + if (!hidden_interfaces.empty()) + { + // Now traverse the tree looking for all named types. + Build_method_tables bmt(this, hidden_interfaces); + this->traverse(&bmt); + } + + // We no longer need the list of interfaces. + + this->interface_types_.clear(); +} + +// This is called for each type. For a named type, for each of the +// interfaces with hidden methods that it implements, create the +// method table. + +int +Build_method_tables::type(Type* type) +{ + Named_type* nt = type->named_type(); + if (nt != NULL) + { + for (std::vector<Interface_type*>::const_iterator p = + this->interfaces_.begin(); + p != this->interfaces_.end(); + ++p) + { + // We ask whether a pointer to the named type implements the + // interface, because a pointer can implement more methods + // than a value. + if ((*p)->implements_interface(Type::make_pointer_type(nt), NULL)) + { + nt->interface_method_table(this->gogo_, *p, false); + nt->interface_method_table(this->gogo_, *p, true); + } + } + } + return TRAVERSE_CONTINUE; +} + +// Traversal class used to check for return statements. + +class Check_return_statements_traverse : public Traverse +{ + public: + Check_return_statements_traverse() + : Traverse(traverse_functions) + { } + + int + function(Named_object*); +}; + +// Check that a function has a return statement if it needs one. + +int +Check_return_statements_traverse::function(Named_object* no) +{ + Function* func = no->func_value(); + const Function_type* fntype = func->type(); + const Typed_identifier_list* results = fntype->results(); + + // We only need a return statement if there is a return value. + if (results == NULL || results->empty()) + return TRAVERSE_CONTINUE; + + if (func->block()->may_fall_through()) + error_at(func->location(), "control reaches end of non-void function"); + + return TRAVERSE_CONTINUE; +} + +// Check return statements. + +void +Gogo::check_return_statements() +{ + Check_return_statements_traverse traverse; + this->traverse(&traverse); +} + +// Get the unique prefix to use before all exported symbols. This +// must be unique across the entire link. + +const std::string& +Gogo::unique_prefix() const +{ + gcc_assert(!this->unique_prefix_.empty()); + return this->unique_prefix_; +} + +// Set the unique prefix to use before all exported symbols. This +// comes from the command line option -fgo-prefix=XXX. + +void +Gogo::set_unique_prefix(const std::string& arg) +{ + gcc_assert(this->unique_prefix_.empty()); + this->unique_prefix_ = arg; + this->unique_prefix_specified_ = true; +} + +// Work out the package priority. It is one more than the maximum +// priority of an imported package. + +int +Gogo::package_priority() const +{ + int priority = 0; + for (Packages::const_iterator p = this->packages_.begin(); + p != this->packages_.end(); + ++p) + if (p->second->priority() > priority) + priority = p->second->priority(); + return priority + 1; +} + +// Export identifiers as requested. + +void +Gogo::do_exports() +{ + // For now we always stream to a section. Later we may want to + // support streaming to a separate file. + Stream_to_section stream; + + Export exp(&stream); + exp.register_builtin_types(this); + exp.export_globals(this->package_name(), + this->unique_prefix(), + this->package_priority(), + (this->need_init_fn_ && !this->is_main_package() + ? this->get_init_fn_name() + : ""), + this->imported_init_fns_, + this->package_->bindings()); +} + +// Find the blocks in order to convert named types defined in blocks. + +class Convert_named_types : public Traverse +{ + public: + Convert_named_types(Gogo* gogo) + : Traverse(traverse_blocks), + gogo_(gogo) + { } + + protected: + int + block(Block* block); + + private: + Gogo* gogo_; +}; + +int +Convert_named_types::block(Block* block) +{ + this->gogo_->convert_named_types_in_bindings(block->bindings()); + return TRAVERSE_CONTINUE; +} + +// Convert all named types to the backend representation. Since named +// types can refer to other types, this needs to be done in the right +// sequence, which is handled by Named_type::convert. Here we arrange +// to call that for each named type. + +void +Gogo::convert_named_types() +{ + this->convert_named_types_in_bindings(this->globals_); + for (Packages::iterator p = this->packages_.begin(); + p != this->packages_.end(); + ++p) + { + Package* package = p->second; + this->convert_named_types_in_bindings(package->bindings()); + } + + Convert_named_types cnt(this); + this->traverse(&cnt); + + // Make all the builtin named types used for type descriptors, and + // then convert them. They will only be written out if they are + // needed. + Type::make_type_descriptor_type(); + Type::make_type_descriptor_ptr_type(); + Function_type::make_function_type_descriptor_type(); + Pointer_type::make_pointer_type_descriptor_type(); + Struct_type::make_struct_type_descriptor_type(); + Array_type::make_array_type_descriptor_type(); + Array_type::make_slice_type_descriptor_type(); + Map_type::make_map_type_descriptor_type(); + Channel_type::make_chan_type_descriptor_type(); + Interface_type::make_interface_type_descriptor_type(); + Type::convert_builtin_named_types(this); + + this->named_types_are_converted_ = true; +} + +// Convert all names types in a set of bindings. + +void +Gogo::convert_named_types_in_bindings(Bindings* bindings) +{ + for (Bindings::const_definitions_iterator p = bindings->begin_definitions(); + p != bindings->end_definitions(); + ++p) + { + if ((*p)->is_type()) + (*p)->type_value()->convert(this); + } +} + +// Class Function. + +Function::Function(Function_type* type, Function* enclosing, Block* block, + source_location location) + : type_(type), enclosing_(enclosing), named_results_(NULL), + closure_var_(NULL), block_(block), location_(location), fndecl_(NULL), + defer_stack_(NULL), calls_recover_(false), is_recover_thunk_(false), + has_recover_thunk_(false) +{ +} + +// Create the named result variables. + +void +Function::create_named_result_variables(Gogo* gogo) +{ + const Typed_identifier_list* results = this->type_->results(); + if (results == NULL + || results->empty() + || results->front().name().empty()) + return; + + this->named_results_ = new Named_results(); + this->named_results_->reserve(results->size()); + + Block* block = this->block_; + int index = 0; + for (Typed_identifier_list::const_iterator p = results->begin(); + p != results->end(); + ++p, ++index) + { + std::string name = p->name(); + if (Gogo::is_sink_name(name)) + { + static int unnamed_result_counter; + char buf[100]; + snprintf(buf, sizeof buf, "_$%d", unnamed_result_counter); + ++unnamed_result_counter; + name = gogo->pack_hidden_name(buf, false); + } + Result_variable* result = new Result_variable(p->type(), this, index); + Named_object* no = block->bindings()->add_result_variable(name, result); + if (no->is_result_variable()) + this->named_results_->push_back(no); + } +} + +// Update the named result variables when cloning a function which +// calls recover. + +void +Function::update_named_result_variables() +{ + if (this->named_results_ == NULL) + return; + + for (Named_results::iterator p = this->named_results_->begin(); + p != this->named_results_->end(); + ++p) + (*p)->result_var_value()->set_function(this); +} + +// Return the closure variable, creating it if necessary. + +Named_object* +Function::closure_var() +{ + if (this->closure_var_ == NULL) + { + // We don't know the type of the variable yet. We add fields as + // we find them. + source_location loc = this->type_->location(); + Struct_field_list* sfl = new Struct_field_list; + Type* struct_type = Type::make_struct_type(sfl, loc); + Variable* var = new Variable(Type::make_pointer_type(struct_type), + NULL, false, true, false, loc); + this->closure_var_ = Named_object::make_variable("closure", NULL, var); + // Note that the new variable is not in any binding contour. + } + return this->closure_var_; +} + +// Set the type of the closure variable. + +void +Function::set_closure_type() +{ + if (this->closure_var_ == NULL) + return; + Named_object* closure = this->closure_var_; + Struct_type* st = closure->var_value()->type()->deref()->struct_type(); + unsigned int index = 0; + for (Closure_fields::const_iterator p = this->closure_fields_.begin(); + p != this->closure_fields_.end(); + ++p, ++index) + { + Named_object* no = p->first; + char buf[20]; + snprintf(buf, sizeof buf, "%u", index); + std::string n = no->name() + buf; + Type* var_type; + if (no->is_variable()) + var_type = no->var_value()->type(); + else + var_type = no->result_var_value()->type(); + Type* field_type = Type::make_pointer_type(var_type); + st->push_field(Struct_field(Typed_identifier(n, field_type, p->second))); + } +} + +// Return whether this function is a method. + +bool +Function::is_method() const +{ + return this->type_->is_method(); +} + +// Add a label definition. + +Label* +Function::add_label_definition(const std::string& label_name, + source_location location) +{ + Label* lnull = NULL; + std::pair<Labels::iterator, bool> ins = + this->labels_.insert(std::make_pair(label_name, lnull)); + if (ins.second) + { + // This is a new label. + Label* label = new Label(label_name); + label->define(location); + ins.first->second = label; + return label; + } + else + { + // The label was already in the hash table. + Label* label = ins.first->second; + if (!label->is_defined()) + { + label->define(location); + return label; + } + else + { + error_at(location, "redefinition of label %qs", + Gogo::message_name(label_name).c_str()); + inform(label->location(), "previous definition of %qs was here", + Gogo::message_name(label_name).c_str()); + return new Label(label_name); + } + } +} + +// Add a reference to a label. + +Label* +Function::add_label_reference(const std::string& label_name) +{ + Label* lnull = NULL; + std::pair<Labels::iterator, bool> ins = + this->labels_.insert(std::make_pair(label_name, lnull)); + if (!ins.second) + { + // The label was already in the hash table. + return ins.first->second; + } + else + { + gcc_assert(ins.first->second == NULL); + Label* label = new Label(label_name); + ins.first->second = label; + return label; + } +} + +// Swap one function with another. This is used when building the +// thunk we use to call a function which calls recover. It may not +// work for any other case. + +void +Function::swap_for_recover(Function *x) +{ + gcc_assert(this->enclosing_ == x->enclosing_); + std::swap(this->named_results_, x->named_results_); + std::swap(this->closure_var_, x->closure_var_); + std::swap(this->block_, x->block_); + gcc_assert(this->location_ == x->location_); + gcc_assert(this->fndecl_ == NULL && x->fndecl_ == NULL); + gcc_assert(this->defer_stack_ == NULL && x->defer_stack_ == NULL); +} + +// Traverse the tree. + +int +Function::traverse(Traverse* traverse) +{ + unsigned int traverse_mask = traverse->traverse_mask(); + + if ((traverse_mask + & (Traverse::traverse_types | Traverse::traverse_expressions)) + != 0) + { + if (Type::traverse(this->type_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + + // FIXME: We should check traverse_functions here if nested + // functions are stored in block bindings. + if (this->block_ != NULL + && (traverse_mask + & (Traverse::traverse_variables + | Traverse::traverse_constants + | Traverse::traverse_blocks + | Traverse::traverse_statements + | Traverse::traverse_expressions + | Traverse::traverse_types)) != 0) + { + if (this->block_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + + return TRAVERSE_CONTINUE; +} + +// Work out types for unspecified variables and constants. + +void +Function::determine_types() +{ + if (this->block_ != NULL) + this->block_->determine_types(); +} + +// Export the function. + +void +Function::export_func(Export* exp, const std::string& name) const +{ + Function::export_func_with_type(exp, name, this->type_); +} + +// Export a function with a type. + +void +Function::export_func_with_type(Export* exp, const std::string& name, + const Function_type* fntype) +{ + exp->write_c_string("func "); + + if (fntype->is_method()) + { + exp->write_c_string("("); + exp->write_type(fntype->receiver()->type()); + exp->write_c_string(") "); + } + + exp->write_string(name); + + exp->write_c_string(" ("); + const Typed_identifier_list* parameters = fntype->parameters(); + if (parameters != NULL) + { + bool is_varargs = fntype->is_varargs(); + bool first = true; + for (Typed_identifier_list::const_iterator p = parameters->begin(); + p != parameters->end(); + ++p) + { + if (first) + first = false; + else + exp->write_c_string(", "); + if (!is_varargs || p + 1 != parameters->end()) + exp->write_type(p->type()); + else + { + exp->write_c_string("..."); + exp->write_type(p->type()->array_type()->element_type()); + } + } + } + exp->write_c_string(")"); + + const Typed_identifier_list* results = fntype->results(); + if (results != NULL) + { + if (results->size() == 1) + { + exp->write_c_string(" "); + exp->write_type(results->begin()->type()); + } + else + { + exp->write_c_string(" ("); + bool first = true; + for (Typed_identifier_list::const_iterator p = results->begin(); + p != results->end(); + ++p) + { + if (first) + first = false; + else + exp->write_c_string(", "); + exp->write_type(p->type()); + } + exp->write_c_string(")"); + } + } + exp->write_c_string(";\n"); +} + +// Import a function. + +void +Function::import_func(Import* imp, std::string* pname, + Typed_identifier** preceiver, + Typed_identifier_list** pparameters, + Typed_identifier_list** presults, + bool* is_varargs) +{ + imp->require_c_string("func "); + + *preceiver = NULL; + if (imp->peek_char() == '(') + { + imp->require_c_string("("); + Type* rtype = imp->read_type(); + *preceiver = new Typed_identifier(Import::import_marker, rtype, + imp->location()); + imp->require_c_string(") "); + } + + *pname = imp->read_identifier(); + + Typed_identifier_list* parameters; + *is_varargs = false; + imp->require_c_string(" ("); + if (imp->peek_char() == ')') + parameters = NULL; + else + { + parameters = new Typed_identifier_list(); + while (true) + { + if (imp->match_c_string("...")) + { + imp->advance(3); + *is_varargs = true; + } + + Type* ptype = imp->read_type(); + if (*is_varargs) + ptype = Type::make_array_type(ptype, NULL); + parameters->push_back(Typed_identifier(Import::import_marker, + ptype, imp->location())); + if (imp->peek_char() != ',') + break; + gcc_assert(!*is_varargs); + imp->require_c_string(", "); + } + } + imp->require_c_string(")"); + *pparameters = parameters; + + Typed_identifier_list* results; + if (imp->peek_char() != ' ') + results = NULL; + else + { + results = new Typed_identifier_list(); + imp->require_c_string(" "); + if (imp->peek_char() != '(') + { + Type* rtype = imp->read_type(); + results->push_back(Typed_identifier(Import::import_marker, rtype, + imp->location())); + } + else + { + imp->require_c_string("("); + while (true) + { + Type* rtype = imp->read_type(); + results->push_back(Typed_identifier(Import::import_marker, + rtype, imp->location())); + if (imp->peek_char() != ',') + break; + imp->require_c_string(", "); + } + imp->require_c_string(")"); + } + } + imp->require_c_string(";\n"); + *presults = results; +} + +// Class Block. + +Block::Block(Block* enclosing, source_location location) + : enclosing_(enclosing), statements_(), + bindings_(new Bindings(enclosing == NULL + ? NULL + : enclosing->bindings())), + start_location_(location), + end_location_(UNKNOWN_LOCATION) +{ +} + +// Add a statement to a block. + +void +Block::add_statement(Statement* statement) +{ + this->statements_.push_back(statement); +} + +// Add a statement to the front of a block. This is slow but is only +// used for reference counts of parameters. + +void +Block::add_statement_at_front(Statement* statement) +{ + this->statements_.insert(this->statements_.begin(), statement); +} + +// Replace a statement in a block. + +void +Block::replace_statement(size_t index, Statement* s) +{ + gcc_assert(index < this->statements_.size()); + this->statements_[index] = s; +} + +// Add a statement before another statement. + +void +Block::insert_statement_before(size_t index, Statement* s) +{ + gcc_assert(index < this->statements_.size()); + this->statements_.insert(this->statements_.begin() + index, s); +} + +// Add a statement after another statement. + +void +Block::insert_statement_after(size_t index, Statement* s) +{ + gcc_assert(index < this->statements_.size()); + this->statements_.insert(this->statements_.begin() + index + 1, s); +} + +// Traverse the tree. + +int +Block::traverse(Traverse* traverse) +{ + unsigned int traverse_mask = traverse->traverse_mask(); + + if ((traverse_mask & Traverse::traverse_blocks) != 0) + { + int t = traverse->block(this); + if (t == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + else if (t == TRAVERSE_SKIP_COMPONENTS) + return TRAVERSE_CONTINUE; + } + + if ((traverse_mask + & (Traverse::traverse_variables + | Traverse::traverse_constants + | Traverse::traverse_expressions + | Traverse::traverse_types)) != 0) + { + for (Bindings::const_definitions_iterator pb = + this->bindings_->begin_definitions(); + pb != this->bindings_->end_definitions(); + ++pb) + { + switch ((*pb)->classification()) + { + case Named_object::NAMED_OBJECT_CONST: + if ((traverse_mask & Traverse::traverse_constants) != 0) + { + if (traverse->constant(*pb, false) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if ((traverse_mask & Traverse::traverse_types) != 0 + || (traverse_mask & Traverse::traverse_expressions) != 0) + { + Type* t = (*pb)->const_value()->type(); + if (t != NULL + && Type::traverse(t, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if ((traverse_mask & Traverse::traverse_expressions) != 0 + || (traverse_mask & Traverse::traverse_types) != 0) + { + if ((*pb)->const_value()->traverse_expression(traverse) + == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + break; + + case Named_object::NAMED_OBJECT_VAR: + case Named_object::NAMED_OBJECT_RESULT_VAR: + if ((traverse_mask & Traverse::traverse_variables) != 0) + { + if (traverse->variable(*pb) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if (((traverse_mask & Traverse::traverse_types) != 0 + || (traverse_mask & Traverse::traverse_expressions) != 0) + && ((*pb)->is_result_variable() + || (*pb)->var_value()->has_type())) + { + Type* t = ((*pb)->is_variable() + ? (*pb)->var_value()->type() + : (*pb)->result_var_value()->type()); + if (t != NULL + && Type::traverse(t, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if ((*pb)->is_variable() + && ((traverse_mask & Traverse::traverse_expressions) != 0 + || (traverse_mask & Traverse::traverse_types) != 0)) + { + if ((*pb)->var_value()->traverse_expression(traverse) + == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + break; + + case Named_object::NAMED_OBJECT_FUNC: + case Named_object::NAMED_OBJECT_FUNC_DECLARATION: + // FIXME: Where will nested functions be found? + gcc_unreachable(); + + case Named_object::NAMED_OBJECT_TYPE: + if ((traverse_mask & Traverse::traverse_types) != 0 + || (traverse_mask & Traverse::traverse_expressions) != 0) + { + if (Type::traverse((*pb)->type_value(), traverse) + == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + break; + + case Named_object::NAMED_OBJECT_TYPE_DECLARATION: + case Named_object::NAMED_OBJECT_UNKNOWN: + break; + + case Named_object::NAMED_OBJECT_PACKAGE: + case Named_object::NAMED_OBJECT_SINK: + gcc_unreachable(); + + default: + gcc_unreachable(); + } + } + } + + // No point in checking traverse_mask here--if we got here we always + // want to walk the statements. The traversal can insert new + // statements before or after the current statement. Inserting + // statements before the current statement requires updating I via + // the pointer; those statements will not be traversed. Any new + // statements inserted after the current statement will be traversed + // in their turn. + for (size_t i = 0; i < this->statements_.size(); ++i) + { + if (this->statements_[i]->traverse(this, &i, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + + return TRAVERSE_CONTINUE; +} + +// Work out types for unspecified variables and constants. + +void +Block::determine_types() +{ + for (Bindings::const_definitions_iterator pb = + this->bindings_->begin_definitions(); + pb != this->bindings_->end_definitions(); + ++pb) + { + if ((*pb)->is_variable()) + (*pb)->var_value()->determine_type(); + else if ((*pb)->is_const()) + (*pb)->const_value()->determine_type(); + } + + for (std::vector<Statement*>::const_iterator ps = this->statements_.begin(); + ps != this->statements_.end(); + ++ps) + (*ps)->determine_types(); +} + +// Return true if the statements in this block may fall through. + +bool +Block::may_fall_through() const +{ + if (this->statements_.empty()) + return true; + return this->statements_.back()->may_fall_through(); +} + +// Class Variable. + +Variable::Variable(Type* type, Expression* init, bool is_global, + bool is_parameter, bool is_receiver, + source_location location) + : type_(type), init_(init), preinit_(NULL), location_(location), + is_global_(is_global), is_parameter_(is_parameter), + is_receiver_(is_receiver), is_varargs_parameter_(false), + is_address_taken_(false), seen_(false), init_is_lowered_(false), + type_from_init_tuple_(false), type_from_range_index_(false), + type_from_range_value_(false), type_from_chan_element_(false), + is_type_switch_var_(false), determined_type_(false) +{ + gcc_assert(type != NULL || init != NULL); + gcc_assert(!is_parameter || init == NULL); +} + +// Traverse the initializer expression. + +int +Variable::traverse_expression(Traverse* traverse) +{ + if (this->preinit_ != NULL) + { + if (this->preinit_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if (this->init_ != NULL) + { + if (Expression::traverse(&this->init_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +// Lower the initialization expression after parsing is complete. + +void +Variable::lower_init_expression(Gogo* gogo, Named_object* function) +{ + if (this->init_ != NULL && !this->init_is_lowered_) + { + if (this->seen_) + { + // We will give an error elsewhere, this is just to prevent + // an infinite loop. + return; + } + this->seen_ = true; + + gogo->lower_expression(function, &this->init_); + + this->seen_ = false; + + this->init_is_lowered_ = true; + } +} + +// Get the preinit block. + +Block* +Variable::preinit_block(Gogo* gogo) +{ + gcc_assert(this->is_global_); + if (this->preinit_ == NULL) + this->preinit_ = new Block(NULL, this->location()); + + // If a global variable has a preinitialization statement, then we + // need to have an initialization function. + gogo->set_need_init_fn(); + + return this->preinit_; +} + +// Add a statement to be run before the initialization expression. + +void +Variable::add_preinit_statement(Gogo* gogo, Statement* s) +{ + Block* b = this->preinit_block(gogo); + b->add_statement(s); + b->set_end_location(s->location()); +} + +// In an assignment which sets a variable to a tuple of EXPR, return +// the type of the first element of the tuple. + +Type* +Variable::type_from_tuple(Expression* expr, bool report_error) const +{ + if (expr->map_index_expression() != NULL) + { + Map_type* mt = expr->map_index_expression()->get_map_type(); + if (mt == NULL) + return Type::make_error_type(); + return mt->val_type(); + } + else if (expr->receive_expression() != NULL) + { + Expression* channel = expr->receive_expression()->channel(); + Type* channel_type = channel->type(); + if (channel_type->channel_type() == NULL) + return Type::make_error_type(); + return channel_type->channel_type()->element_type(); + } + else + { + if (report_error) + error_at(this->location(), "invalid tuple definition"); + return Type::make_error_type(); + } +} + +// Given EXPR used in a range clause, return either the index type or +// the value type of the range, depending upon GET_INDEX_TYPE. + +Type* +Variable::type_from_range(Expression* expr, bool get_index_type, + bool report_error) const +{ + Type* t = expr->type(); + if (t->array_type() != NULL + || (t->points_to() != NULL + && t->points_to()->array_type() != NULL + && !t->points_to()->is_open_array_type())) + { + if (get_index_type) + return Type::lookup_integer_type("int"); + else + return t->deref()->array_type()->element_type(); + } + else if (t->is_string_type()) + return Type::lookup_integer_type("int"); + else if (t->map_type() != NULL) + { + if (get_index_type) + return t->map_type()->key_type(); + else + return t->map_type()->val_type(); + } + else if (t->channel_type() != NULL) + { + if (get_index_type) + return t->channel_type()->element_type(); + else + { + if (report_error) + error_at(this->location(), + "invalid definition of value variable for channel range"); + return Type::make_error_type(); + } + } + else + { + if (report_error) + error_at(this->location(), "invalid type for range clause"); + return Type::make_error_type(); + } +} + +// EXPR should be a channel. Return the channel's element type. + +Type* +Variable::type_from_chan_element(Expression* expr, bool report_error) const +{ + Type* t = expr->type(); + if (t->channel_type() != NULL) + return t->channel_type()->element_type(); + else + { + if (report_error) + error_at(this->location(), "expected channel"); + return Type::make_error_type(); + } +} + +// Return the type of the Variable. This may be called before +// Variable::determine_type is called, which means that we may need to +// get the type from the initializer. FIXME: If we combine lowering +// with type determination, then this should be unnecessary. + +Type* +Variable::type() +{ + // A variable in a type switch with a nil case will have the wrong + // type here. This gets fixed up in determine_type, below. + Type* type = this->type_; + Expression* init = this->init_; + if (this->is_type_switch_var_ + && this->type_->is_nil_constant_as_type()) + { + Type_guard_expression* tge = this->init_->type_guard_expression(); + gcc_assert(tge != NULL); + init = tge->expr(); + type = NULL; + } + + if (this->seen_) + { + if (this->type_ == NULL || !this->type_->is_error_type()) + { + error_at(this->location_, "variable initializer refers to itself"); + this->type_ = Type::make_error_type(); + } + return this->type_; + } + + this->seen_ = true; + + if (type != NULL) + ; + else if (this->type_from_init_tuple_) + type = this->type_from_tuple(init, false); + else if (this->type_from_range_index_ || this->type_from_range_value_) + type = this->type_from_range(init, this->type_from_range_index_, false); + else if (this->type_from_chan_element_) + type = this->type_from_chan_element(init, false); + else + { + gcc_assert(init != NULL); + type = init->type(); + gcc_assert(type != NULL); + + // Variables should not have abstract types. + if (type->is_abstract()) + type = type->make_non_abstract_type(); + + if (type->is_void_type()) + type = Type::make_error_type(); + } + + this->seen_ = false; + + return type; +} + +// Fetch the type from a const pointer, in which case it should have +// been set already. + +Type* +Variable::type() const +{ + gcc_assert(this->type_ != NULL); + return this->type_; +} + +// Set the type if necessary. + +void +Variable::determine_type() +{ + if (this->determined_type_) + return; + this->determined_type_ = true; + + if (this->preinit_ != NULL) + this->preinit_->determine_types(); + + // A variable in a type switch with a nil case will have the wrong + // type here. It will have an initializer which is a type guard. + // We want to initialize it to the value without the type guard, and + // use the type of that value as well. + if (this->is_type_switch_var_ && this->type_->is_nil_constant_as_type()) + { + Type_guard_expression* tge = this->init_->type_guard_expression(); + gcc_assert(tge != NULL); + this->type_ = NULL; + this->init_ = tge->expr(); + } + + if (this->init_ == NULL) + gcc_assert(this->type_ != NULL && !this->type_->is_abstract()); + else if (this->type_from_init_tuple_) + { + Expression *init = this->init_; + init->determine_type_no_context(); + this->type_ = this->type_from_tuple(init, true); + this->init_ = NULL; + } + else if (this->type_from_range_index_ || this->type_from_range_value_) + { + Expression* init = this->init_; + init->determine_type_no_context(); + this->type_ = this->type_from_range(init, this->type_from_range_index_, + true); + this->init_ = NULL; + } + else + { + // type_from_chan_element_ should have been cleared during + // lowering. + gcc_assert(!this->type_from_chan_element_); + + Type_context context(this->type_, false); + this->init_->determine_type(&context); + if (this->type_ == NULL) + { + Type* type = this->init_->type(); + gcc_assert(type != NULL); + if (type->is_abstract()) + type = type->make_non_abstract_type(); + + if (type->is_void_type()) + { + error_at(this->location_, "variable has no type"); + type = Type::make_error_type(); + } + else if (type->is_nil_type()) + { + error_at(this->location_, "variable defined to nil type"); + type = Type::make_error_type(); + } + else if (type->is_call_multiple_result_type()) + { + error_at(this->location_, + "single variable set to multiple value function call"); + type = Type::make_error_type(); + } + + this->type_ = type; + } + } +} + +// Export the variable + +void +Variable::export_var(Export* exp, const std::string& name) const +{ + gcc_assert(this->is_global_); + exp->write_c_string("var "); + exp->write_string(name); + exp->write_c_string(" "); + exp->write_type(this->type()); + exp->write_c_string(";\n"); +} + +// Import a variable. + +void +Variable::import_var(Import* imp, std::string* pname, Type** ptype) +{ + imp->require_c_string("var "); + *pname = imp->read_identifier(); + imp->require_c_string(" "); + *ptype = imp->read_type(); + imp->require_c_string(";\n"); +} + +// Class Named_constant. + +// Traverse the initializer expression. + +int +Named_constant::traverse_expression(Traverse* traverse) +{ + return Expression::traverse(&this->expr_, traverse); +} + +// Determine the type of the constant. + +void +Named_constant::determine_type() +{ + if (this->type_ != NULL) + { + Type_context context(this->type_, false); + this->expr_->determine_type(&context); + } + else + { + // A constant may have an abstract type. + Type_context context(NULL, true); + this->expr_->determine_type(&context); + this->type_ = this->expr_->type(); + gcc_assert(this->type_ != NULL); + } +} + +// Indicate that we found and reported an error for this constant. + +void +Named_constant::set_error() +{ + this->type_ = Type::make_error_type(); + this->expr_ = Expression::make_error(this->location_); +} + +// Export a constant. + +void +Named_constant::export_const(Export* exp, const std::string& name) const +{ + exp->write_c_string("const "); + exp->write_string(name); + exp->write_c_string(" "); + if (!this->type_->is_abstract()) + { + exp->write_type(this->type_); + exp->write_c_string(" "); + } + exp->write_c_string("= "); + this->expr()->export_expression(exp); + exp->write_c_string(";\n"); +} + +// Import a constant. + +void +Named_constant::import_const(Import* imp, std::string* pname, Type** ptype, + Expression** pexpr) +{ + imp->require_c_string("const "); + *pname = imp->read_identifier(); + imp->require_c_string(" "); + if (imp->peek_char() == '=') + *ptype = NULL; + else + { + *ptype = imp->read_type(); + imp->require_c_string(" "); + } + imp->require_c_string("= "); + *pexpr = Expression::import_expression(imp); + imp->require_c_string(";\n"); +} + +// Add a method. + +Named_object* +Type_declaration::add_method(const std::string& name, Function* function) +{ + Named_object* ret = Named_object::make_function(name, NULL, function); + this->methods_.push_back(ret); + return ret; +} + +// Add a method declaration. + +Named_object* +Type_declaration::add_method_declaration(const std::string& name, + Function_type* type, + source_location location) +{ + Named_object* ret = Named_object::make_function_declaration(name, NULL, type, + location); + this->methods_.push_back(ret); + return ret; +} + +// Return whether any methods ere defined. + +bool +Type_declaration::has_methods() const +{ + return !this->methods_.empty(); +} + +// Define methods for the real type. + +void +Type_declaration::define_methods(Named_type* nt) +{ + for (Methods::const_iterator p = this->methods_.begin(); + p != this->methods_.end(); + ++p) + nt->add_existing_method(*p); +} + +// We are using the type. Return true if we should issue a warning. + +bool +Type_declaration::using_type() +{ + bool ret = !this->issued_warning_; + this->issued_warning_ = true; + return ret; +} + +// Class Unknown_name. + +// Set the real named object. + +void +Unknown_name::set_real_named_object(Named_object* no) +{ + gcc_assert(this->real_named_object_ == NULL); + gcc_assert(!no->is_unknown()); + this->real_named_object_ = no; +} + +// Class Named_object. + +Named_object::Named_object(const std::string& name, + const Package* package, + Classification classification) + : name_(name), package_(package), classification_(classification), + tree_(NULL) +{ + if (Gogo::is_sink_name(name)) + gcc_assert(classification == NAMED_OBJECT_SINK); +} + +// Make an unknown name. This is used by the parser. The name must +// be resolved later. Unknown names are only added in the current +// package. + +Named_object* +Named_object::make_unknown_name(const std::string& name, + source_location location) +{ + Named_object* named_object = new Named_object(name, NULL, + NAMED_OBJECT_UNKNOWN); + Unknown_name* value = new Unknown_name(location); + named_object->u_.unknown_value = value; + return named_object; +} + +// Make a constant. + +Named_object* +Named_object::make_constant(const Typed_identifier& tid, + const Package* package, Expression* expr, + int iota_value) +{ + Named_object* named_object = new Named_object(tid.name(), package, + NAMED_OBJECT_CONST); + Named_constant* named_constant = new Named_constant(tid.type(), expr, + iota_value, + tid.location()); + named_object->u_.const_value = named_constant; + return named_object; +} + +// Make a named type. + +Named_object* +Named_object::make_type(const std::string& name, const Package* package, + Type* type, source_location location) +{ + Named_object* named_object = new Named_object(name, package, + NAMED_OBJECT_TYPE); + Named_type* named_type = Type::make_named_type(named_object, type, location); + named_object->u_.type_value = named_type; + return named_object; +} + +// Make a type declaration. + +Named_object* +Named_object::make_type_declaration(const std::string& name, + const Package* package, + source_location location) +{ + Named_object* named_object = new Named_object(name, package, + NAMED_OBJECT_TYPE_DECLARATION); + Type_declaration* type_declaration = new Type_declaration(location); + named_object->u_.type_declaration = type_declaration; + return named_object; +} + +// Make a variable. + +Named_object* +Named_object::make_variable(const std::string& name, const Package* package, + Variable* variable) +{ + Named_object* named_object = new Named_object(name, package, + NAMED_OBJECT_VAR); + named_object->u_.var_value = variable; + return named_object; +} + +// Make a result variable. + +Named_object* +Named_object::make_result_variable(const std::string& name, + Result_variable* result) +{ + Named_object* named_object = new Named_object(name, NULL, + NAMED_OBJECT_RESULT_VAR); + named_object->u_.result_var_value = result; + return named_object; +} + +// Make a sink. This is used for the special blank identifier _. + +Named_object* +Named_object::make_sink() +{ + return new Named_object("_", NULL, NAMED_OBJECT_SINK); +} + +// Make a named function. + +Named_object* +Named_object::make_function(const std::string& name, const Package* package, + Function* function) +{ + Named_object* named_object = new Named_object(name, package, + NAMED_OBJECT_FUNC); + named_object->u_.func_value = function; + return named_object; +} + +// Make a function declaration. + +Named_object* +Named_object::make_function_declaration(const std::string& name, + const Package* package, + Function_type* fntype, + source_location location) +{ + Named_object* named_object = new Named_object(name, package, + NAMED_OBJECT_FUNC_DECLARATION); + Function_declaration *func_decl = new Function_declaration(fntype, location); + named_object->u_.func_declaration_value = func_decl; + return named_object; +} + +// Make a package. + +Named_object* +Named_object::make_package(const std::string& alias, Package* package) +{ + Named_object* named_object = new Named_object(alias, NULL, + NAMED_OBJECT_PACKAGE); + named_object->u_.package_value = package; + return named_object; +} + +// Return the name to use in an error message. + +std::string +Named_object::message_name() const +{ + if (this->package_ == NULL) + return Gogo::message_name(this->name_); + std::string ret = Gogo::message_name(this->package_->name()); + ret += '.'; + ret += Gogo::message_name(this->name_); + return ret; +} + +// Set the type when a declaration is defined. + +void +Named_object::set_type_value(Named_type* named_type) +{ + gcc_assert(this->classification_ == NAMED_OBJECT_TYPE_DECLARATION); + Type_declaration* td = this->u_.type_declaration; + td->define_methods(named_type); + Named_object* in_function = td->in_function(); + if (in_function != NULL) + named_type->set_in_function(in_function); + delete td; + this->classification_ = NAMED_OBJECT_TYPE; + this->u_.type_value = named_type; +} + +// Define a function which was previously declared. + +void +Named_object::set_function_value(Function* function) +{ + gcc_assert(this->classification_ == NAMED_OBJECT_FUNC_DECLARATION); + this->classification_ = NAMED_OBJECT_FUNC; + // FIXME: We should free the old value. + this->u_.func_value = function; +} + +// Declare an unknown object as a type declaration. + +void +Named_object::declare_as_type() +{ + gcc_assert(this->classification_ == NAMED_OBJECT_UNKNOWN); + Unknown_name* unk = this->u_.unknown_value; + this->classification_ = NAMED_OBJECT_TYPE_DECLARATION; + this->u_.type_declaration = new Type_declaration(unk->location()); + delete unk; +} + +// Return the location of a named object. + +source_location +Named_object::location() const +{ + switch (this->classification_) + { + default: + case NAMED_OBJECT_UNINITIALIZED: + gcc_unreachable(); + + case NAMED_OBJECT_UNKNOWN: + return this->unknown_value()->location(); + + case NAMED_OBJECT_CONST: + return this->const_value()->location(); + + case NAMED_OBJECT_TYPE: + return this->type_value()->location(); + + case NAMED_OBJECT_TYPE_DECLARATION: + return this->type_declaration_value()->location(); + + case NAMED_OBJECT_VAR: + return this->var_value()->location(); + + case NAMED_OBJECT_RESULT_VAR: + return this->result_var_value()->function()->location(); + + case NAMED_OBJECT_SINK: + gcc_unreachable(); + + case NAMED_OBJECT_FUNC: + return this->func_value()->location(); + + case NAMED_OBJECT_FUNC_DECLARATION: + return this->func_declaration_value()->location(); + + case NAMED_OBJECT_PACKAGE: + return this->package_value()->location(); + } +} + +// Export a named object. + +void +Named_object::export_named_object(Export* exp) const +{ + switch (this->classification_) + { + default: + case NAMED_OBJECT_UNINITIALIZED: + case NAMED_OBJECT_UNKNOWN: + gcc_unreachable(); + + case NAMED_OBJECT_CONST: + this->const_value()->export_const(exp, this->name_); + break; + + case NAMED_OBJECT_TYPE: + this->type_value()->export_named_type(exp, this->name_); + break; + + case NAMED_OBJECT_TYPE_DECLARATION: + error_at(this->type_declaration_value()->location(), + "attempt to export %<%s%> which was declared but not defined", + this->message_name().c_str()); + break; + + case NAMED_OBJECT_FUNC_DECLARATION: + this->func_declaration_value()->export_func(exp, this->name_); + break; + + case NAMED_OBJECT_VAR: + this->var_value()->export_var(exp, this->name_); + break; + + case NAMED_OBJECT_RESULT_VAR: + case NAMED_OBJECT_SINK: + gcc_unreachable(); + + case NAMED_OBJECT_FUNC: + this->func_value()->export_func(exp, this->name_); + break; + } +} + +// Class Bindings. + +Bindings::Bindings(Bindings* enclosing) + : enclosing_(enclosing), named_objects_(), bindings_() +{ +} + +// Clear imports. + +void +Bindings::clear_file_scope() +{ + Contour::iterator p = this->bindings_.begin(); + while (p != this->bindings_.end()) + { + bool keep; + if (p->second->package() != NULL) + keep = false; + else if (p->second->is_package()) + keep = false; + else if (p->second->is_function() + && !p->second->func_value()->type()->is_method() + && Gogo::unpack_hidden_name(p->second->name()) == "init") + keep = false; + else + keep = true; + + if (keep) + ++p; + else + p = this->bindings_.erase(p); + } +} + +// Look up a symbol. + +Named_object* +Bindings::lookup(const std::string& name) const +{ + Contour::const_iterator p = this->bindings_.find(name); + if (p != this->bindings_.end()) + return p->second->resolve(); + else if (this->enclosing_ != NULL) + return this->enclosing_->lookup(name); + else + return NULL; +} + +// Look up a symbol locally. + +Named_object* +Bindings::lookup_local(const std::string& name) const +{ + Contour::const_iterator p = this->bindings_.find(name); + if (p == this->bindings_.end()) + return NULL; + return p->second; +} + +// Remove an object from a set of bindings. This is used for a +// special case in thunks for functions which call recover. + +void +Bindings::remove_binding(Named_object* no) +{ + Contour::iterator pb = this->bindings_.find(no->name()); + gcc_assert(pb != this->bindings_.end()); + this->bindings_.erase(pb); + for (std::vector<Named_object*>::iterator pn = this->named_objects_.begin(); + pn != this->named_objects_.end(); + ++pn) + { + if (*pn == no) + { + this->named_objects_.erase(pn); + return; + } + } + gcc_unreachable(); +} + +// Add a method to the list of objects. This is not added to the +// lookup table. This is so that we have a single list of objects +// declared at the top level, which we walk through when it's time to +// convert to trees. + +void +Bindings::add_method(Named_object* method) +{ + this->named_objects_.push_back(method); +} + +// Add a generic Named_object to a Contour. + +Named_object* +Bindings::add_named_object_to_contour(Contour* contour, + Named_object* named_object) +{ + gcc_assert(named_object == named_object->resolve()); + const std::string& name(named_object->name()); + gcc_assert(!Gogo::is_sink_name(name)); + + std::pair<Contour::iterator, bool> ins = + contour->insert(std::make_pair(name, named_object)); + if (!ins.second) + { + // The name was already there. + if (named_object->package() != NULL + && ins.first->second->package() == named_object->package() + && (ins.first->second->classification() + == named_object->classification())) + { + // This is a second import of the same object. + return ins.first->second; + } + ins.first->second = this->new_definition(ins.first->second, + named_object); + return ins.first->second; + } + else + { + // Don't push declarations on the list. We push them on when + // and if we find the definitions. That way we genericize the + // functions in order. + if (!named_object->is_type_declaration() + && !named_object->is_function_declaration() + && !named_object->is_unknown()) + this->named_objects_.push_back(named_object); + return named_object; + } +} + +// We had an existing named object OLD_OBJECT, and we've seen a new +// one NEW_OBJECT with the same name. FIXME: This does not free the +// new object when we don't need it. + +Named_object* +Bindings::new_definition(Named_object* old_object, Named_object* new_object) +{ + std::string reason; + switch (old_object->classification()) + { + default: + case Named_object::NAMED_OBJECT_UNINITIALIZED: + gcc_unreachable(); + + case Named_object::NAMED_OBJECT_UNKNOWN: + { + Named_object* real = old_object->unknown_value()->real_named_object(); + if (real != NULL) + return this->new_definition(real, new_object); + gcc_assert(!new_object->is_unknown()); + old_object->unknown_value()->set_real_named_object(new_object); + if (!new_object->is_type_declaration() + && !new_object->is_function_declaration()) + this->named_objects_.push_back(new_object); + return new_object; + } + + case Named_object::NAMED_OBJECT_CONST: + break; + + case Named_object::NAMED_OBJECT_TYPE: + if (new_object->is_type_declaration()) + return old_object; + break; + + case Named_object::NAMED_OBJECT_TYPE_DECLARATION: + if (new_object->is_type_declaration()) + return old_object; + if (new_object->is_type()) + { + old_object->set_type_value(new_object->type_value()); + new_object->type_value()->set_named_object(old_object); + this->named_objects_.push_back(old_object); + return old_object; + } + break; + + case Named_object::NAMED_OBJECT_VAR: + case Named_object::NAMED_OBJECT_RESULT_VAR: + break; + + case Named_object::NAMED_OBJECT_SINK: + gcc_unreachable(); + + case Named_object::NAMED_OBJECT_FUNC: + if (new_object->is_function_declaration()) + { + if (!new_object->func_declaration_value()->asm_name().empty()) + sorry("__asm__ for function definitions"); + Function_type* old_type = old_object->func_value()->type(); + Function_type* new_type = + new_object->func_declaration_value()->type(); + if (old_type->is_valid_redeclaration(new_type, &reason)) + return old_object; + } + break; + + case Named_object::NAMED_OBJECT_FUNC_DECLARATION: + { + Function_type* old_type = old_object->func_declaration_value()->type(); + if (new_object->is_function_declaration()) + { + Function_type* new_type = + new_object->func_declaration_value()->type(); + if (old_type->is_valid_redeclaration(new_type, &reason)) + return old_object; + } + if (new_object->is_function()) + { + Function_type* new_type = new_object->func_value()->type(); + if (old_type->is_valid_redeclaration(new_type, &reason)) + { + if (!old_object->func_declaration_value()->asm_name().empty()) + sorry("__asm__ for function definitions"); + old_object->set_function_value(new_object->func_value()); + this->named_objects_.push_back(old_object); + return old_object; + } + } + } + break; + + case Named_object::NAMED_OBJECT_PACKAGE: + if (new_object->is_package() + && (old_object->package_value()->name() + == new_object->package_value()->name())) + return old_object; + + break; + } + + std::string n = old_object->message_name(); + if (reason.empty()) + error_at(new_object->location(), "redefinition of %qs", n.c_str()); + else + error_at(new_object->location(), "redefinition of %qs: %s", n.c_str(), + reason.c_str()); + + inform(old_object->location(), "previous definition of %qs was here", + n.c_str()); + + return old_object; +} + +// Add a named type. + +Named_object* +Bindings::add_named_type(Named_type* named_type) +{ + return this->add_named_object(named_type->named_object()); +} + +// Add a function. + +Named_object* +Bindings::add_function(const std::string& name, const Package* package, + Function* function) +{ + return this->add_named_object(Named_object::make_function(name, package, + function)); +} + +// Add a function declaration. + +Named_object* +Bindings::add_function_declaration(const std::string& name, + const Package* package, + Function_type* type, + source_location location) +{ + Named_object* no = Named_object::make_function_declaration(name, package, + type, location); + return this->add_named_object(no); +} + +// Define a type which was previously declared. + +void +Bindings::define_type(Named_object* no, Named_type* type) +{ + no->set_type_value(type); + this->named_objects_.push_back(no); +} + +// Traverse bindings. + +int +Bindings::traverse(Traverse* traverse, bool is_global) +{ + unsigned int traverse_mask = traverse->traverse_mask(); + + // We don't use an iterator because we permit the traversal to add + // new global objects. + for (size_t i = 0; i < this->named_objects_.size(); ++i) + { + Named_object* p = this->named_objects_[i]; + switch (p->classification()) + { + case Named_object::NAMED_OBJECT_CONST: + if ((traverse_mask & Traverse::traverse_constants) != 0) + { + if (traverse->constant(p, is_global) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if ((traverse_mask & Traverse::traverse_types) != 0 + || (traverse_mask & Traverse::traverse_expressions) != 0) + { + Type* t = p->const_value()->type(); + if (t != NULL + && Type::traverse(t, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (p->const_value()->traverse_expression(traverse) + == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + break; + + case Named_object::NAMED_OBJECT_VAR: + case Named_object::NAMED_OBJECT_RESULT_VAR: + if ((traverse_mask & Traverse::traverse_variables) != 0) + { + if (traverse->variable(p) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if (((traverse_mask & Traverse::traverse_types) != 0 + || (traverse_mask & Traverse::traverse_expressions) != 0) + && (p->is_result_variable() + || p->var_value()->has_type())) + { + Type* t = (p->is_variable() + ? p->var_value()->type() + : p->result_var_value()->type()); + if (t != NULL + && Type::traverse(t, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if (p->is_variable() + && ((traverse_mask & Traverse::traverse_types) != 0 + || (traverse_mask & Traverse::traverse_expressions) != 0)) + { + if (p->var_value()->traverse_expression(traverse) + == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + break; + + case Named_object::NAMED_OBJECT_FUNC: + if ((traverse_mask & Traverse::traverse_functions) != 0) + { + int t = traverse->function(p); + if (t == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + else if (t == TRAVERSE_SKIP_COMPONENTS) + break; + } + + if ((traverse_mask + & (Traverse::traverse_variables + | Traverse::traverse_constants + | Traverse::traverse_functions + | Traverse::traverse_blocks + | Traverse::traverse_statements + | Traverse::traverse_expressions + | Traverse::traverse_types)) != 0) + { + if (p->func_value()->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + break; + + case Named_object::NAMED_OBJECT_PACKAGE: + // These are traversed in Gogo::traverse. + gcc_assert(is_global); + break; + + case Named_object::NAMED_OBJECT_TYPE: + if ((traverse_mask & Traverse::traverse_types) != 0 + || (traverse_mask & Traverse::traverse_expressions) != 0) + { + if (Type::traverse(p->type_value(), traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + break; + + case Named_object::NAMED_OBJECT_TYPE_DECLARATION: + case Named_object::NAMED_OBJECT_FUNC_DECLARATION: + case Named_object::NAMED_OBJECT_UNKNOWN: + break; + + case Named_object::NAMED_OBJECT_SINK: + default: + gcc_unreachable(); + } + } + + return TRAVERSE_CONTINUE; +} + +// Class Package. + +Package::Package(const std::string& name, const std::string& unique_prefix, + source_location location) + : name_(name), unique_prefix_(unique_prefix), bindings_(new Bindings(NULL)), + priority_(0), location_(location), used_(false), is_imported_(false), + uses_sink_alias_(false) +{ + gcc_assert(!name.empty() && !unique_prefix.empty()); +} + +// Set the priority. We may see multiple priorities for an imported +// package; we want to use the largest one. + +void +Package::set_priority(int priority) +{ + if (priority > this->priority_) + this->priority_ = priority; +} + +// Determine types of constants. Everything else in a package +// (variables, function declarations) should already have a fixed +// type. Constants may have abstract types. + +void +Package::determine_types() +{ + Bindings* bindings = this->bindings_; + for (Bindings::const_definitions_iterator p = bindings->begin_definitions(); + p != bindings->end_definitions(); + ++p) + { + if ((*p)->is_const()) + (*p)->const_value()->determine_type(); + } +} + +// Class Traverse. + +// Destructor. + +Traverse::~Traverse() +{ + if (this->types_seen_ != NULL) + delete this->types_seen_; + if (this->expressions_seen_ != NULL) + delete this->expressions_seen_; +} + +// Record that we are looking at a type, and return true if we have +// already seen it. + +bool +Traverse::remember_type(const Type* type) +{ + if (type->is_error_type()) + return true; + gcc_assert((this->traverse_mask() & traverse_types) != 0 + || (this->traverse_mask() & traverse_expressions) != 0); + // We only have to remember named types, as they are the only ones + // we can see multiple times in a traversal. + if (type->classification() != Type::TYPE_NAMED) + return false; + if (this->types_seen_ == NULL) + this->types_seen_ = new Types_seen(); + std::pair<Types_seen::iterator, bool> ins = this->types_seen_->insert(type); + return !ins.second; +} + +// Record that we are looking at an expression, and return true if we +// have already seen it. + +bool +Traverse::remember_expression(const Expression* expression) +{ + gcc_assert((this->traverse_mask() & traverse_types) != 0 + || (this->traverse_mask() & traverse_expressions) != 0); + if (this->expressions_seen_ == NULL) + this->expressions_seen_ = new Expressions_seen(); + std::pair<Expressions_seen::iterator, bool> ins = + this->expressions_seen_->insert(expression); + return !ins.second; +} + +// The default versions of these functions should never be called: the +// traversal mask indicates which functions may be called. + +int +Traverse::variable(Named_object*) +{ + gcc_unreachable(); +} + +int +Traverse::constant(Named_object*, bool) +{ + gcc_unreachable(); +} + +int +Traverse::function(Named_object*) +{ + gcc_unreachable(); +} + +int +Traverse::block(Block*) +{ + gcc_unreachable(); +} + +int +Traverse::statement(Block*, size_t*, Statement*) +{ + gcc_unreachable(); +} + +int +Traverse::expression(Expression**) +{ + gcc_unreachable(); +} + +int +Traverse::type(Type*) +{ + gcc_unreachable(); +} diff --git a/gcc/go/gofrontend/gogo.h b/gcc/go/gofrontend/gogo.h new file mode 100644 index 000000000..7a52a51a2 --- /dev/null +++ b/gcc/go/gofrontend/gogo.h @@ -0,0 +1,2533 @@ +// gogo.h -- Go frontend parsed representation. -*- C++ -*- + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef GO_GOGO_H +#define GO_GOGO_H + +class Traverse; +class Type; +class Type_hash_identical; +class Type_equal; +class Type_identical; +class Typed_identifier; +class Typed_identifier_list; +class Function_type; +class Expression; +class Statement; +class Block; +class Function; +class Bindings; +class Package; +class Variable; +class Pointer_type; +class Struct_type; +class Struct_field; +class Struct_field_list; +class Array_type; +class Map_type; +class Channel_type; +class Interface_type; +class Named_type; +class Forward_declaration_type; +class Method; +class Methods; +class Named_object; +class Label; +class Translate_context; +class Export; +class Import; + +// This file declares the basic classes used to hold the internal +// representation of Go which is built by the parser. + +// An initialization function for an imported package. This is a +// magic function which initializes variables and runs the "init" +// function. + +class Import_init +{ + public: + Import_init(const std::string& package_name, const std::string& init_name, + int priority) + : package_name_(package_name), init_name_(init_name), priority_(priority) + { } + + // The name of the package being imported. + const std::string& + package_name() const + { return this->package_name_; } + + // The name of the package's init function. + const std::string& + init_name() const + { return this->init_name_; } + + // The priority of the initialization function. Functions with a + // lower priority number must be run first. + int + priority() const + { return this->priority_; } + + private: + // The name of the package being imported. + std::string package_name_; + // The name of the package's init function. + std::string init_name_; + // The priority. + int priority_; +}; + +// For sorting purposes. + +inline bool +operator<(const Import_init& i1, const Import_init& i2) +{ + if (i1.priority() < i2.priority()) + return true; + if (i1.priority() > i2.priority()) + return false; + if (i1.package_name() != i2.package_name()) + return i1.package_name() < i2.package_name(); + return i1.init_name() < i2.init_name(); +} + +// The holder for the internal representation of the entire +// compilation unit. + +class Gogo +{ + public: + // Create the IR, passing in the sizes of the types "int" and + // "uintptr" in bits. + Gogo(int int_type_size, int pointer_size); + + // Get the package name. + const std::string& + package_name() const; + + // Set the package name. + void + set_package_name(const std::string&, source_location); + + // Return whether this is the "main" package. + bool + is_main_package() const; + + // If necessary, adjust the name to use for a hidden symbol. We add + // a prefix of the package name, so that hidden symbols in different + // packages do not collide. + std::string + pack_hidden_name(const std::string& name, bool is_exported) const + { + return (is_exported + ? name + : ('.' + this->unique_prefix() + + '.' + this->package_name() + + '.' + name)); + } + + // Unpack a name which may have been hidden. Returns the + // user-visible name of the object. + static std::string + unpack_hidden_name(const std::string& name) + { return name[0] != '.' ? name : name.substr(name.rfind('.') + 1); } + + // Return whether a possibly packed name is hidden. + static bool + is_hidden_name(const std::string& name) + { return name[0] == '.'; } + + // Return the package prefix of a hidden name. + static std::string + hidden_name_prefix(const std::string& name) + { + gcc_assert(Gogo::is_hidden_name(name)); + return name.substr(1, name.rfind('.') - 1); + } + + // Given a name which may or may not have been hidden, return the + // name to use in an error message. + static std::string + message_name(const std::string& name); + + // Return whether a name is the blank identifier _. + static bool + is_sink_name(const std::string& name) + { + return (name[0] == '.' + && name[name.length() - 1] == '_' + && name[name.length() - 2] == '.'); + } + + // Return the unique prefix to use for all exported symbols. + const std::string& + unique_prefix() const; + + // Set the unique prefix. + void + set_unique_prefix(const std::string&); + + // Return the priority to use for the package we are compiling. + // This is two more than the largest priority of any package we + // import. + int + package_priority() const; + + // Import a package. FILENAME is the file name argument, LOCAL_NAME + // is the local name to give to the package. If LOCAL_NAME is empty + // the declarations are added to the global scope. + void + import_package(const std::string& filename, const std::string& local_name, + bool is_local_name_exported, source_location); + + // Whether we are the global binding level. + bool + in_global_scope() const; + + // Look up a name in the current binding contours. + Named_object* + lookup(const std::string&, Named_object** pfunction) const; + + // Look up a name in the current block. + Named_object* + lookup_in_block(const std::string&) const; + + // Look up a name in the global namespace--the universal scope. + Named_object* + lookup_global(const char*) const; + + // Add a new imported package. REAL_NAME is the real name of the + // package. ALIAS is the alias of the package; this may be the same + // as REAL_NAME. This sets *PADD_TO_GLOBALS if symbols added to + // this package should be added to the global namespace; this is + // true if the alias is ".". LOCATION is the location of the import + // statement. This returns the new package, or NULL on error. + Package* + add_imported_package(const std::string& real_name, const std::string& alias, + bool is_alias_exported, + const std::string& unique_prefix, + source_location location, + bool* padd_to_globals); + + // Register a package. This package may or may not be imported. + // This returns the Package structure for the package, creating if + // it necessary. + Package* + register_package(const std::string& name, const std::string& unique_prefix, + source_location); + + // Start compiling a function. ADD_METHOD_TO_TYPE is true if a + // method function should be added to the type of its receiver. + Named_object* + start_function(const std::string& name, Function_type* type, + bool add_method_to_type, source_location); + + // Finish compiling a function. + void + finish_function(source_location); + + // Return the current function. + Named_object* + current_function() const; + + // Start a new block. This is not initially associated with a + // function. + void + start_block(source_location); + + // Finish the current block and return it. + Block* + finish_block(source_location); + + // Declare an unknown name. This is used while parsing. The name + // must be resolved by the end of the parse. Unknown names are + // always added at the package level. + Named_object* + add_unknown_name(const std::string& name, source_location); + + // Declare a function. + Named_object* + declare_function(const std::string&, Function_type*, source_location); + + // Add a label. + Label* + add_label_definition(const std::string&, source_location); + + // Add a label reference. + Label* + add_label_reference(const std::string&); + + // Add a statement to the current block. + void + add_statement(Statement*); + + // Add a block to the current block. + void + add_block(Block*, source_location); + + // Add a constant. + Named_object* + add_constant(const Typed_identifier&, Expression*, int iota_value); + + // Add a type. + void + add_type(const std::string&, Type*, source_location); + + // Add a named type. This is used for builtin types, and to add an + // imported type to the global scope. + void + add_named_type(Named_type*); + + // Declare a type. + Named_object* + declare_type(const std::string&, source_location); + + // Declare a type at the package level. This is used when the + // parser sees an unknown name where a type name is required. + Named_object* + declare_package_type(const std::string&, source_location); + + // Define a type which was already declared. + void + define_type(Named_object*, Named_type*); + + // Add a variable. + Named_object* + add_variable(const std::string&, Variable*); + + // Add a sink--a reference to the blank identifier _. + Named_object* + add_sink(); + + // Add a named object to the current namespace. This is used for + // import . "package". + void + add_named_object(Named_object*); + + // Return a name to use for a thunk function. A thunk function is + // one we create during the compilation, for a go statement or a + // defer statement or a method expression. + static std::string + thunk_name(); + + // Return whether an object is a thunk. + static bool + is_thunk(const Named_object*); + + // Note that we've seen an interface type. This is used to build + // all required interface method tables. + void + record_interface_type(Interface_type*); + + // Note that we need an initialization function. + void + set_need_init_fn() + { this->need_init_fn_ = true; } + + // Clear out all names in file scope. This is called when we start + // parsing a new file. + void + clear_file_scope(); + + // Traverse the tree. See the Traverse class. + void + traverse(Traverse*); + + // Define the predeclared global names. + void + define_global_names(); + + // Verify and complete all types. + void + verify_types(); + + // Lower the parse tree. + void + lower_parse_tree(); + + // Lower an expression. + void + lower_expression(Named_object* function, Expression**); + + // Lower a constant. + void + lower_constant(Named_object*); + + // Finalize the method lists and build stub methods for named types. + void + finalize_methods(); + + // Work out the types to use for unspecified variables and + // constants. + void + determine_types(); + + // Type check the program. + void + check_types(); + + // Check the types in a single block. This is used for complicated + // go statements. + void + check_types_in_block(Block*); + + // Check for return statements. + void + check_return_statements(); + + // Do all exports. + void + do_exports(); + + // Add an import control function for an imported package to the + // list. + void + add_import_init_fn(const std::string& package_name, + const std::string& init_name, int prio); + + // Turn short-cut operators (&&, ||) into explicit if statements. + void + remove_shortcuts(); + + // Use temporary variables to force order of evaluation. + void + order_evaluations(); + + // Build thunks for functions which call recover. + void + build_recover_thunks(); + + // Simplify statements which might use thunks: go and defer + // statements. + void + simplify_thunk_statements(); + + // Convert named types to the backend representation. + void + convert_named_types(); + + // Convert named types in a list of bindings. + void + convert_named_types_in_bindings(Bindings*); + + // True if named types have been converted to the backend + // representation. + bool + named_types_are_converted() const + { return this->named_types_are_converted_; } + + // Write out the global values. + void + write_globals(); + + // Build a call to a builtin function. PDECL should point to a NULL + // initialized static pointer which will hold the fndecl. NAME is + // the name of the function. NARGS is the number of arguments. + // RETTYPE is the return type. It is followed by NARGS pairs of + // type and argument (both trees). + static tree + call_builtin(tree* pdecl, source_location, const char* name, int nargs, + tree rettype, ...); + + // Build a call to the runtime error function. + static tree + runtime_error(int code, source_location); + + // Build a builtin struct with a list of fields. + static tree + builtin_struct(tree* ptype, const char* struct_name, tree struct_type, + int nfields, ...); + + // Mark a function declaration as a builtin library function. + static void + mark_fndecl_as_builtin_library(tree fndecl); + + // Build the type of the struct that holds a slice for the given + // element type. + tree + slice_type_tree(tree element_type_tree); + + // Given a tree for a slice type, return the tree for the element + // type. + static tree + slice_element_type_tree(tree slice_type_tree); + + // Build a constructor for a slice. SLICE_TYPE_TREE is the type of + // the slice. VALUES points to the values. COUNT is the size, + // CAPACITY is the capacity. If CAPACITY is NULL, it is set to + // COUNT. + static tree + slice_constructor(tree slice_type_tree, tree values, tree count, + tree capacity); + + // Build a constructor for an empty slice. SLICE_TYPE_TREE is the + // type of the slice. + static tree + empty_slice_constructor(tree slice_type_tree); + + // Build a map descriptor. + tree + map_descriptor(Map_type*); + + // Return a tree for the type of a map descriptor. This is struct + // __go_map_descriptor in libgo/runtime/map.h. This is the same for + // all map types. + tree + map_descriptor_type(); + + // Build a type descriptor for TYPE using INITIALIZER as the type + // descriptor. This builds a new decl stored in *PDECL. + void + build_type_descriptor_decl(const Type*, Expression* initializer, + tree* pdecl); + + // Build required interface method tables. + void + build_interface_method_tables(); + + // Build an interface method table for a type: a list of function + // pointers, one for each interface method. This returns a decl. + tree + interface_method_table_for_type(const Interface_type*, Named_type*, + bool is_pointer); + + // Return a tree which allocate SIZE bytes to hold values of type + // TYPE. + tree + allocate_memory(Type *type, tree size, source_location); + + // Return a type to use for pointer to const char. + static tree + const_char_pointer_type_tree(); + + // Build a string constant with the right type. + static tree + string_constant_tree(const std::string&); + + // Build a Go string constant. This returns a pointer to the + // constant. + tree + go_string_constant_tree(const std::string&); + + // Send a value on a channel. + static tree + send_on_channel(tree channel, tree val, bool blocking, bool for_select, + source_location); + + // Receive a value from a channel. + static tree + receive_from_channel(tree type_tree, tree channel, bool for_select, + source_location); + + // Return a tree for receiving an integer on a channel. + static tree + receive_as_64bit_integer(tree type, tree channel, bool blocking, + bool for_select); + + + // Make a trampoline which calls FNADDR passing CLOSURE. + tree + make_trampoline(tree fnaddr, tree closure, source_location); + + private: + // During parsing, we keep a stack of functions. Each function on + // the stack is one that we are currently parsing. For each + // function, we keep track of the current stack of blocks. + struct Open_function + { + // The function. + Named_object* function; + // The stack of active blocks in the function. + std::vector<Block*> blocks; + }; + + // The stack of functions. + typedef std::vector<Open_function> Open_functions; + + // Create trees for implicit builtin functions. + void + define_builtin_function_trees(); + + // Set up the built-in unsafe package. + void + import_unsafe(const std::string&, bool is_exported, source_location); + + // Add a new imported package. + Named_object* + add_package(const std::string& real_name, const std::string& alias, + const std::string& unique_prefix, source_location location); + + // Return the current binding contour. + Bindings* + current_bindings(); + + const Bindings* + current_bindings() const; + + // Return the current block. + Block* + current_block(); + + // Get the name of the magic initialization function. + const std::string& + get_init_fn_name(); + + // Get the decl for the magic initialization function. + tree + initialization_function_decl(); + + // Write the magic initialization function. + void + write_initialization_function(tree fndecl, tree init_stmt_list); + + // Initialize imported packages. + void + init_imports(tree*); + + // Register variables with the garbage collector. + void + register_gc_vars(const std::vector<Named_object*>&, tree*); + + // Build a pointer to a Go string constant. This returns a pointer + // to the pointer. + tree + ptr_go_string_constant_tree(const std::string&); + + // Return the name to use for a type descriptor decl for an unnamed + // type. + std::string + unnamed_type_descriptor_decl_name(const Type* type); + + // Return the name to use for a type descriptor decl for a type + // named NO, defined in IN_FUNCTION. + std::string + type_descriptor_decl_name(const Named_object* no, + const Named_object* in_function); + + // Where a type descriptor should be defined. + enum Type_descriptor_location + { + // Defined in this file. + TYPE_DESCRIPTOR_DEFINED, + // Defined in some other file. + TYPE_DESCRIPTOR_UNDEFINED, + // Common definition which may occur in multiple files. + TYPE_DESCRIPTOR_COMMON + }; + + // Return where the decl for TYPE should be defined. + Type_descriptor_location + type_descriptor_location(const Type* type); + + // Return the type of a trampoline. + static tree + trampoline_type_tree(); + + // Type used to map import names to packages. + typedef std::map<std::string, Package*> Imports; + + // Type used to map package names to packages. + typedef std::map<std::string, Package*> Packages; + + // Type used to map special names in the sys package. + typedef std::map<std::string, std::string> Sys_names; + + // Hash table mapping map types to map descriptor decls. + typedef Unordered_map_hash(const Map_type*, tree, Type_hash_identical, + Type_identical) Map_descriptors; + + // Map unnamed types to type descriptor decls. + typedef Unordered_map_hash(const Type*, tree, Type_hash_identical, + Type_identical) Type_descriptor_decls; + + // The package we are compiling. + Package* package_; + // The list of currently open functions during parsing. + Open_functions functions_; + // The global binding contour. This includes the builtin functions + // and the package we are compiling. + Bindings* globals_; + // Mapping from import file names to packages. + Imports imports_; + // Whether the magic unsafe package was imported. + bool imported_unsafe_; + // Mapping from package names we have seen to packages. This does + // not include the package we are compiling. + Packages packages_; + // Mapping from map types to map descriptors. + Map_descriptors* map_descriptors_; + // Mapping from unnamed types to type descriptor decls. + Type_descriptor_decls* type_descriptor_decls_; + // The functions named "init", if there are any. + std::vector<Named_object*> init_functions_; + // Whether we need a magic initialization function. + bool need_init_fn_; + // The name of the magic initialization function. + std::string init_fn_name_; + // A list of import control variables for packages that we import. + std::set<Import_init> imported_init_fns_; + // The unique prefix used for all global symbols. + std::string unique_prefix_; + // Whether an explicit unique prefix was set by -fgo-prefix. + bool unique_prefix_specified_; + // A list of interface types defined while parsing. + std::vector<Interface_type*> interface_types_; + // Whether named types have been converted. + bool named_types_are_converted_; +}; + +// A block of statements. + +class Block +{ + public: + Block(Block* enclosing, source_location); + + // Return the enclosing block. + const Block* + enclosing() const + { return this->enclosing_; } + + // Return the bindings of the block. + Bindings* + bindings() + { return this->bindings_; } + + const Bindings* + bindings() const + { return this->bindings_; } + + // Look at the block's statements. + const std::vector<Statement*>* + statements() const + { return &this->statements_; } + + // Return the start location. This is normally the location of the + // left curly brace which starts the block. + source_location + start_location() const + { return this->start_location_; } + + // Return the end location. This is normally the location of the + // right curly brace which ends the block. + source_location + end_location() const + { return this->end_location_; } + + // Add a statement to the block. + void + add_statement(Statement*); + + // Add a statement to the front of the block. + void + add_statement_at_front(Statement*); + + // Replace a statement in a block. + void + replace_statement(size_t index, Statement*); + + // Add a Statement before statement number INDEX. + void + insert_statement_before(size_t index, Statement*); + + // Add a Statement after statement number INDEX. + void + insert_statement_after(size_t index, Statement*); + + // Set the end location of the block. + void + set_end_location(source_location location) + { this->end_location_ = location; } + + // Traverse the tree. + int + traverse(Traverse*); + + // Set final types for unspecified variables and constants. + void + determine_types(); + + // Return true if execution of this block may fall through to the + // next block. + bool + may_fall_through() const; + + // Return a tree of the code in this block. + tree + get_tree(Translate_context*); + + // Iterate over statements. + + typedef std::vector<Statement*>::iterator iterator; + + iterator + begin() + { return this->statements_.begin(); } + + iterator + end() + { return this->statements_.end(); } + + private: + // Enclosing block. + Block* enclosing_; + // Statements in the block. + std::vector<Statement*> statements_; + // Binding contour. + Bindings* bindings_; + // Location of start of block. + source_location start_location_; + // Location of end of block. + source_location end_location_; +}; + +// A function. + +class Function +{ + public: + Function(Function_type* type, Function*, Block*, source_location); + + // Return the function's type. + Function_type* + type() const + { return this->type_; } + + // Return the enclosing function if there is one. + Function* + enclosing() + { return this->enclosing_; } + + // Set the enclosing function. This is used when building thunks + // for functions which call recover. + void + set_enclosing(Function* enclosing) + { + gcc_assert(this->enclosing_ == NULL); + this->enclosing_ = enclosing; + } + + // Create the named result variables in the outer block. + void + create_named_result_variables(Gogo*); + + // Update the named result variables when cloning a function which + // calls recover. + void + update_named_result_variables(); + + // Add a new field to the closure variable. + void + add_closure_field(Named_object* var, source_location loc) + { this->closure_fields_.push_back(std::make_pair(var, loc)); } + + // Whether this function needs a closure. + bool + needs_closure() const + { return !this->closure_fields_.empty(); } + + // Return the closure variable, creating it if necessary. This is + // passed to the function as a static chain parameter. + Named_object* + closure_var(); + + // Set the closure variable. This is used when building thunks for + // functions which call recover. + void + set_closure_var(Named_object* v) + { + gcc_assert(this->closure_var_ == NULL); + this->closure_var_ = v; + } + + // Return the variable for a reference to field INDEX in the closure + // variable. + Named_object* + enclosing_var(unsigned int index) + { + gcc_assert(index < this->closure_fields_.size()); + return closure_fields_[index].first; + } + + // Set the type of the closure variable if there is one. + void + set_closure_type(); + + // Get the block of statements associated with the function. + Block* + block() const + { return this->block_; } + + // Get the location of the start of the function. + source_location + location() const + { return this->location_; } + + // Return whether this function is actually a method. + bool + is_method() const; + + // Add a label definition to the function. + Label* + add_label_definition(const std::string& label_name, source_location); + + // Add a label reference to a function. + Label* + add_label_reference(const std::string& label_name); + + // Whether this function calls the predeclared recover function. + bool + calls_recover() const + { return this->calls_recover_; } + + // Record that this function calls the predeclared recover function. + // This is set during the lowering pass. + void + set_calls_recover() + { this->calls_recover_ = true; } + + // Whether this is a recover thunk function. + bool + is_recover_thunk() const + { return this->is_recover_thunk_; } + + // Record that this is a thunk built for a function which calls + // recover. + void + set_is_recover_thunk() + { this->is_recover_thunk_ = true; } + + // Whether this function already has a recover thunk. + bool + has_recover_thunk() const + { return this->has_recover_thunk_; } + + // Record that this function already has a recover thunk. + void + set_has_recover_thunk() + { this->has_recover_thunk_ = true; } + + // Swap with another function. Used only for the thunk which calls + // recover. + void + swap_for_recover(Function *); + + // Traverse the tree. + int + traverse(Traverse*); + + // Determine types in the function. + void + determine_types(); + + // Return the function's decl given an identifier. + tree + get_or_make_decl(Gogo*, Named_object*, tree id); + + // Return the function's decl after it has been built. + tree + get_decl() const + { + gcc_assert(this->fndecl_ != NULL); + return this->fndecl_; + } + + // Set the function decl to hold a tree of the function code. + void + build_tree(Gogo*, Named_object*); + + // Get the value to return when not explicitly specified. May also + // add statements to execute first to STMT_LIST. + tree + return_value(Gogo*, Named_object*, source_location, tree* stmt_list) const; + + // Get a tree for the variable holding the defer stack. + tree + defer_stack(source_location); + + // Export the function. + void + export_func(Export*, const std::string& name) const; + + // Export a function with a type. + static void + export_func_with_type(Export*, const std::string& name, + const Function_type*); + + // Import a function. + static void + import_func(Import*, std::string* pname, Typed_identifier** receiver, + Typed_identifier_list** pparameters, + Typed_identifier_list** presults, bool* is_varargs); + + private: + // Type for mapping from label names to Label objects. + typedef Unordered_map(std::string, Label*) Labels; + + tree + make_receiver_parm_decl(Gogo*, Named_object*, tree); + + tree + copy_parm_to_heap(Gogo*, Named_object*, tree); + + void + build_defer_wrapper(Gogo*, Named_object*, tree*, tree*); + + typedef std::vector<Named_object*> Named_results; + + typedef std::vector<std::pair<Named_object*, + source_location> > Closure_fields; + + // The function's type. + Function_type* type_; + // The enclosing function. This is NULL when there isn't one, which + // is the normal case. + Function* enclosing_; + // The named result variables, if any. + Named_results* named_results_; + // If there is a closure, this is the list of variables which appear + // in the closure. This is created by the parser, and then resolved + // to a real type when we lower parse trees. + Closure_fields closure_fields_; + // The closure variable, passed as a parameter using the static + // chain parameter. Normally NULL. + Named_object* closure_var_; + // The outer block of statements in the function. + Block* block_; + // The source location of the start of the function. + source_location location_; + // Labels defined or referenced in the function. + Labels labels_; + // The function decl. + tree fndecl_; + // A variable holding the defer stack variable. This is NULL unless + // we actually need a defer stack. + tree defer_stack_; + // True if this function calls the predeclared recover function. + bool calls_recover_; + // True if this a thunk built for a function which calls recover. + bool is_recover_thunk_; + // True if this function already has a recover thunk. + bool has_recover_thunk_; +}; + +// A function declaration. + +class Function_declaration +{ + public: + Function_declaration(Function_type* fntype, source_location location) + : fntype_(fntype), location_(location), asm_name_(), fndecl_(NULL) + { } + + Function_type* + type() const + { return this->fntype_; } + + source_location + location() const + { return this->location_; } + + const std::string& + asm_name() const + { return this->asm_name_; } + + // Set the assembler name. + void + set_asm_name(const std::string& asm_name) + { this->asm_name_ = asm_name; } + + // Return a decl for the function given an identifier. + tree + get_or_make_decl(Gogo*, Named_object*, tree id); + + // Export a function declaration. + void + export_func(Export* exp, const std::string& name) const + { Function::export_func_with_type(exp, name, this->fntype_); } + + private: + // The type of the function. + Function_type* fntype_; + // The location of the declaration. + source_location location_; + // The assembler name: this is the name to use in references to the + // function. This is normally empty. + std::string asm_name_; + // The function decl if needed. + tree fndecl_; +}; + +// A variable. + +class Variable +{ + public: + Variable(Type*, Expression*, bool is_global, bool is_parameter, + bool is_receiver, source_location); + + // Get the type of the variable. + Type* + type(); + + Type* + type() const; + + // Return whether the type is defined yet. + bool + has_type() const + { return this->type_ != NULL; } + + // Get the initial value. + Expression* + init() const + { return this->init_; } + + // Return whether there are any preinit statements. + bool + has_pre_init() const + { return this->preinit_ != NULL; } + + // Return the preinit statements if any. + Block* + preinit() const + { return this->preinit_; } + + // Return whether this is a global variable. + bool + is_global() const + { return this->is_global_; } + + // Return whether this is a function parameter. + bool + is_parameter() const + { return this->is_parameter_; } + + // Return whether this is the receiver parameter of a method. + bool + is_receiver() const + { return this->is_receiver_; } + + // Change this parameter to be a receiver. This is used when + // creating the thunks created for functions which call recover. + void + set_is_receiver() + { + gcc_assert(this->is_parameter_); + this->is_receiver_ = true; + } + + // Change this parameter to not be a receiver. This is used when + // creating the thunks created for functions which call recover. + void + set_is_not_receiver() + { + gcc_assert(this->is_parameter_); + this->is_receiver_ = false; + } + + // Return whether this is the varargs parameter of a function. + bool + is_varargs_parameter() const + { return this->is_varargs_parameter_; } + + // Whether this variable's address is taken. + bool + is_address_taken() const + { return this->is_address_taken_; } + + // Whether this variable should live in the heap. + bool + is_in_heap() const + { return this->is_address_taken_ && !this->is_global_; } + + // Get the source location of the variable's declaration. + source_location + location() const + { return this->location_; } + + // Record that this is the varargs parameter of a function. + void + set_is_varargs_parameter() + { + gcc_assert(this->is_parameter_); + this->is_varargs_parameter_ = true; + } + + // Clear the initial value; used for error handling. + void + clear_init() + { this->init_ = NULL; } + + // Set the initial value; used for converting shortcuts. + void + set_init(Expression* init) + { this->init_ = init; } + + // Get the preinit block, a block of statements to be run before the + // initialization expression. + Block* + preinit_block(Gogo*); + + // Add a statement to be run before the initialization expression. + // This is only used for global variables. + void + add_preinit_statement(Gogo*, Statement*); + + // Lower the initialization expression after parsing is complete. + void + lower_init_expression(Gogo*, Named_object*); + + // A special case: the init value is used only to determine the + // type. This is used if the variable is defined using := with the + // comma-ok form of a map index or a receive expression. The init + // value is actually the map index expression or receive expression. + // We use this because we may not know the right type at parse time. + void + set_type_from_init_tuple() + { this->type_from_init_tuple_ = true; } + + // Another special case: the init value is used only to determine + // the type. This is used if the variable is defined using := with + // a range clause. The init value is the range expression. The + // type of the variable is the index type of the range expression + // (i.e., the first value returned by a range). + void + set_type_from_range_index() + { this->type_from_range_index_ = true; } + + // Another special case: like set_type_from_range_index, but the + // type is the value type of the range expression (i.e., the second + // value returned by a range). + void + set_type_from_range_value() + { this->type_from_range_value_ = true; } + + // Another special case: the init value is used only to determine + // the type. This is used if the variable is defined using := with + // a case in a select statement. The init value is the channel. + // The type of the variable is the channel's element type. + void + set_type_from_chan_element() + { this->type_from_chan_element_ = true; } + + // After we lower the select statement, we once again set the type + // from the initialization expression. + void + clear_type_from_chan_element() + { + gcc_assert(this->type_from_chan_element_); + this->type_from_chan_element_ = false; + } + + // Note that this variable was created for a type switch clause. + void + set_is_type_switch_var() + { this->is_type_switch_var_ = true; } + + // Traverse the initializer expression. + int + traverse_expression(Traverse*); + + // Determine the type of the variable if necessary. + void + determine_type(); + + // Note that something takes the address of this variable. + void + set_address_taken() + { this->is_address_taken_ = true; } + + // Get the initial value of the variable as a tree. This may only + // be called if has_pre_init() returns false. + tree + get_init_tree(Gogo*, Named_object* function); + + // Return a series of statements which sets the value of the + // variable in DECL. This should only be called is has_pre_init() + // returns true. DECL may be NULL for a sink variable. + tree + get_init_block(Gogo*, Named_object* function, tree decl); + + // Export the variable. + void + export_var(Export*, const std::string& name) const; + + // Import a variable. + static void + import_var(Import*, std::string* pname, Type** ptype); + + private: + // The type of a tuple. + Type* + type_from_tuple(Expression*, bool) const; + + // The type of a range. + Type* + type_from_range(Expression*, bool, bool) const; + + // The element type of a channel. + Type* + type_from_chan_element(Expression*, bool) const; + + // The variable's type. This may be NULL if the type is set from + // the expression. + Type* type_; + // The initial value. This may be NULL if the variable should be + // initialized to the default value for the type. + Expression* init_; + // Statements to run before the init statement. + Block* preinit_; + // Location of variable definition. + source_location location_; + // Whether this is a global variable. + bool is_global_ : 1; + // Whether this is a function parameter. + bool is_parameter_ : 1; + // Whether this is the receiver parameter of a method. + bool is_receiver_ : 1; + // Whether this is the varargs parameter of a function. + bool is_varargs_parameter_ : 1; + // Whether something takes the address of this variable. + bool is_address_taken_ : 1; + // True if we have seen this variable in a traversal. + bool seen_ : 1; + // True if we have lowered the initialization expression. + bool init_is_lowered_ : 1; + // True if init is a tuple used to set the type. + bool type_from_init_tuple_ : 1; + // True if init is a range clause and the type is the index type. + bool type_from_range_index_ : 1; + // True if init is a range clause and the type is the value type. + bool type_from_range_value_ : 1; + // True if init is a channel and the type is the channel's element type. + bool type_from_chan_element_ : 1; + // True if this is a variable created for a type switch case. + bool is_type_switch_var_ : 1; + // True if we have determined types. + bool determined_type_ : 1; +}; + +// A variable which is really the name for a function return value, or +// part of one. + +class Result_variable +{ + public: + Result_variable(Type* type, Function* function, int index) + : type_(type), function_(function), index_(index), + is_address_taken_(false) + { } + + // Get the type of the result variable. + Type* + type() const + { return this->type_; } + + // Get the function that this is associated with. + Function* + function() const + { return this->function_; } + + // Index in the list of function results. + int + index() const + { return this->index_; } + + // Whether this variable's address is taken. + bool + is_address_taken() const + { return this->is_address_taken_; } + + // Note that something takes the address of this variable. + void + set_address_taken() + { this->is_address_taken_ = true; } + + // Whether this variable should live in the heap. + bool + is_in_heap() const + { return this->is_address_taken_; } + + // Set the function. This is used when cloning functions which call + // recover. + void + set_function(Function* function) + { this->function_ = function; } + + private: + // Type of result variable. + Type* type_; + // Function with which this is associated. + Function* function_; + // Index in list of results. + int index_; + // Whether something takes the address of this variable. + bool is_address_taken_; +}; + +// The value we keep for a named constant. This lets us hold a type +// and an expression. + +class Named_constant +{ + public: + Named_constant(Type* type, Expression* expr, int iota_value, + source_location location) + : type_(type), expr_(expr), iota_value_(iota_value), location_(location), + lowering_(false) + { } + + Type* + type() const + { return this->type_; } + + Expression* + expr() const + { return this->expr_; } + + int + iota_value() const + { return this->iota_value_; } + + source_location + location() const + { return this->location_; } + + // Whether we are lowering. + bool + lowering() const + { return this->lowering_; } + + // Set that we are lowering. + void + set_lowering() + { this->lowering_ = true; } + + // We are no longer lowering. + void + clear_lowering() + { this->lowering_ = false; } + + // Traverse the expression. + int + traverse_expression(Traverse*); + + // Determine the type of the constant if necessary. + void + determine_type(); + + // Indicate that we found and reported an error for this constant. + void + set_error(); + + // Export the constant. + void + export_const(Export*, const std::string& name) const; + + // Import a constant. + static void + import_const(Import*, std::string*, Type**, Expression**); + + private: + // The type of the constant. + Type* type_; + // The expression for the constant. + Expression* expr_; + // If the predeclared constant iota is used in EXPR_, this is the + // value it will have. We do this because at parse time we don't + // know whether the name "iota" will refer to the predeclared + // constant or to something else. We put in the right value in when + // we lower. + int iota_value_; + // The location of the definition. + source_location location_; + // Whether we are currently lowering this constant. + bool lowering_; +}; + +// A type declaration. + +class Type_declaration +{ + public: + Type_declaration(source_location location) + : location_(location), in_function_(NULL), methods_(), + issued_warning_(false) + { } + + // Return the location. + source_location + location() const + { return this->location_; } + + // Return the function in which this type is declared. This will + // return NULL for a type declared in global scope. + Named_object* + in_function() + { return this->in_function_; } + + // Set the function in which this type is declared. + void + set_in_function(Named_object* f) + { this->in_function_ = f; } + + // Add a method to this type. This is used when methods are defined + // before the type. + Named_object* + add_method(const std::string& name, Function* function); + + // Add a method declaration to this type. + Named_object* + add_method_declaration(const std::string& name, Function_type* type, + source_location location); + + // Return whether any methods were defined. + bool + has_methods() const; + + // Define methods when the real type is known. + void + define_methods(Named_type*); + + // This is called if we are trying to use this type. It returns + // true if we should issue a warning. + bool + using_type(); + + private: + typedef std::vector<Named_object*> Methods; + + // The location of the type declaration. + source_location location_; + // If this type is declared in a function, a pointer back to the + // function in which it is defined. + Named_object* in_function_; + // Methods defined before the type is defined. + Methods methods_; + // True if we have issued a warning about a use of this type + // declaration when it is undefined. + bool issued_warning_; +}; + +// An unknown object. These are created by the parser for forward +// references to names which have not been seen before. In a correct +// program, these will always point to a real definition by the end of +// the parse. Because they point to another Named_object, these may +// only be referenced by Unknown_expression objects. + +class Unknown_name +{ + public: + Unknown_name(source_location location) + : location_(location), real_named_object_(NULL) + { } + + // Return the location where this name was first seen. + source_location + location() const + { return this->location_; } + + // Return the real named object that this points to, or NULL if it + // was never resolved. + Named_object* + real_named_object() const + { return this->real_named_object_; } + + // Set the real named object that this points to. + void + set_real_named_object(Named_object* no); + + private: + // The location where this name was first seen. + source_location location_; + // The real named object when it is known. + Named_object* + real_named_object_; +}; + +// A named object named. This is the result of a declaration. We +// don't use a superclass because they all have to be handled +// differently. + +class Named_object +{ + public: + enum Classification + { + // An uninitialized Named_object. We should never see this. + NAMED_OBJECT_UNINITIALIZED, + // An unknown name. This is used for forward references. In a + // correct program, these will all be resolved by the end of the + // parse. + NAMED_OBJECT_UNKNOWN, + // A const. + NAMED_OBJECT_CONST, + // A type. + NAMED_OBJECT_TYPE, + // A forward type declaration. + NAMED_OBJECT_TYPE_DECLARATION, + // A var. + NAMED_OBJECT_VAR, + // A result variable in a function. + NAMED_OBJECT_RESULT_VAR, + // The blank identifier--the special variable named _. + NAMED_OBJECT_SINK, + // A func. + NAMED_OBJECT_FUNC, + // A forward func declaration. + NAMED_OBJECT_FUNC_DECLARATION, + // A package. + NAMED_OBJECT_PACKAGE + }; + + // Return the classification. + Classification + classification() const + { return this->classification_; } + + // Classifiers. + + bool + is_unknown() const + { return this->classification_ == NAMED_OBJECT_UNKNOWN; } + + bool + is_const() const + { return this->classification_ == NAMED_OBJECT_CONST; } + + bool + is_type() const + { return this->classification_ == NAMED_OBJECT_TYPE; } + + bool + is_type_declaration() const + { return this->classification_ == NAMED_OBJECT_TYPE_DECLARATION; } + + bool + is_variable() const + { return this->classification_ == NAMED_OBJECT_VAR; } + + bool + is_result_variable() const + { return this->classification_ == NAMED_OBJECT_RESULT_VAR; } + + bool + is_sink() const + { return this->classification_ == NAMED_OBJECT_SINK; } + + bool + is_function() const + { return this->classification_ == NAMED_OBJECT_FUNC; } + + bool + is_function_declaration() const + { return this->classification_ == NAMED_OBJECT_FUNC_DECLARATION; } + + bool + is_package() const + { return this->classification_ == NAMED_OBJECT_PACKAGE; } + + // Creators. + + static Named_object* + make_unknown_name(const std::string& name, source_location); + + static Named_object* + make_constant(const Typed_identifier&, const Package*, Expression*, + int iota_value); + + static Named_object* + make_type(const std::string&, const Package*, Type*, source_location); + + static Named_object* + make_type_declaration(const std::string&, const Package*, source_location); + + static Named_object* + make_variable(const std::string&, const Package*, Variable*); + + static Named_object* + make_result_variable(const std::string&, Result_variable*); + + static Named_object* + make_sink(); + + static Named_object* + make_function(const std::string&, const Package*, Function*); + + static Named_object* + make_function_declaration(const std::string&, const Package*, Function_type*, + source_location); + + static Named_object* + make_package(const std::string& alias, Package* package); + + // Getters. + + Unknown_name* + unknown_value() + { + gcc_assert(this->classification_ == NAMED_OBJECT_UNKNOWN); + return this->u_.unknown_value; + } + + const Unknown_name* + unknown_value() const + { + gcc_assert(this->classification_ == NAMED_OBJECT_UNKNOWN); + return this->u_.unknown_value; + } + + Named_constant* + const_value() + { + gcc_assert(this->classification_ == NAMED_OBJECT_CONST); + return this->u_.const_value; + } + + const Named_constant* + const_value() const + { + gcc_assert(this->classification_ == NAMED_OBJECT_CONST); + return this->u_.const_value; + } + + Named_type* + type_value() + { + gcc_assert(this->classification_ == NAMED_OBJECT_TYPE); + return this->u_.type_value; + } + + const Named_type* + type_value() const + { + gcc_assert(this->classification_ == NAMED_OBJECT_TYPE); + return this->u_.type_value; + } + + Type_declaration* + type_declaration_value() + { + gcc_assert(this->classification_ == NAMED_OBJECT_TYPE_DECLARATION); + return this->u_.type_declaration; + } + + const Type_declaration* + type_declaration_value() const + { + gcc_assert(this->classification_ == NAMED_OBJECT_TYPE_DECLARATION); + return this->u_.type_declaration; + } + + Variable* + var_value() + { + gcc_assert(this->classification_ == NAMED_OBJECT_VAR); + return this->u_.var_value; + } + + const Variable* + var_value() const + { + gcc_assert(this->classification_ == NAMED_OBJECT_VAR); + return this->u_.var_value; + } + + Result_variable* + result_var_value() + { + gcc_assert(this->classification_ == NAMED_OBJECT_RESULT_VAR); + return this->u_.result_var_value; + } + + const Result_variable* + result_var_value() const + { + gcc_assert(this->classification_ == NAMED_OBJECT_RESULT_VAR); + return this->u_.result_var_value; + } + + Function* + func_value() + { + gcc_assert(this->classification_ == NAMED_OBJECT_FUNC); + return this->u_.func_value; + } + + const Function* + func_value() const + { + gcc_assert(this->classification_ == NAMED_OBJECT_FUNC); + return this->u_.func_value; + } + + Function_declaration* + func_declaration_value() + { + gcc_assert(this->classification_ == NAMED_OBJECT_FUNC_DECLARATION); + return this->u_.func_declaration_value; + } + + const Function_declaration* + func_declaration_value() const + { + gcc_assert(this->classification_ == NAMED_OBJECT_FUNC_DECLARATION); + return this->u_.func_declaration_value; + } + + Package* + package_value() + { + gcc_assert(this->classification_ == NAMED_OBJECT_PACKAGE); + return this->u_.package_value; + } + + const Package* + package_value() const + { + gcc_assert(this->classification_ == NAMED_OBJECT_PACKAGE); + return this->u_.package_value; + } + + const std::string& + name() const + { return this->name_; } + + // Return the name to use in an error message. The difference is + // that if this Named_object is defined in a different package, this + // will return PACKAGE.NAME. + std::string + message_name() const; + + const Package* + package() const + { return this->package_; } + + // Resolve an unknown value if possible. This returns the same + // Named_object or a new one. + Named_object* + resolve() + { + Named_object* ret = this; + if (this->is_unknown()) + { + Named_object* r = this->unknown_value()->real_named_object(); + if (r != NULL) + ret = r; + } + return ret; + } + + const Named_object* + resolve() const + { + const Named_object* ret = this; + if (this->is_unknown()) + { + const Named_object* r = this->unknown_value()->real_named_object(); + if (r != NULL) + ret = r; + } + return ret; + } + + // The location where this object was defined or referenced. + source_location + location() const; + + // Return a tree for the external identifier for this object. + tree + get_id(Gogo*); + + // Return a tree representing this object. + tree + get_tree(Gogo*, Named_object* function); + + // Define a type declaration. + void + set_type_value(Named_type*); + + // Define a function declaration. + void + set_function_value(Function*); + + // Declare an unknown name as a type declaration. + void + declare_as_type(); + + // Export this object. + void + export_named_object(Export*) const; + + private: + Named_object(const std::string&, const Package*, Classification); + + // The name of the object. + std::string name_; + // The package that this object is in. This is NULL if it is in the + // file we are compiling. + const Package* package_; + // The type of object this is. + Classification classification_; + // The real data. + union + { + Unknown_name* unknown_value; + Named_constant* const_value; + Named_type* type_value; + Type_declaration* type_declaration; + Variable* var_value; + Result_variable* result_var_value; + Function* func_value; + Function_declaration* func_declaration_value; + Package* package_value; + } u_; + // The DECL tree for this object if we have already converted it. + tree tree_; +}; + +// A binding contour. This binds names to objects. + +class Bindings +{ + public: + // Type for mapping from names to objects. + typedef Unordered_map(std::string, Named_object*) Contour; + + Bindings(Bindings* enclosing); + + // Add an unknown name. + Named_object* + add_unknown_name(const std::string& name, source_location location) + { + return this->add_named_object(Named_object::make_unknown_name(name, + location)); + } + + // Add a constant. + Named_object* + add_constant(const Typed_identifier& tid, const Package* package, + Expression* expr, int iota_value) + { + return this->add_named_object(Named_object::make_constant(tid, package, + expr, + iota_value)); + } + + // Add a type. + Named_object* + add_type(const std::string& name, const Package* package, Type* type, + source_location location) + { + return this->add_named_object(Named_object::make_type(name, package, type, + location)); + } + + // Add a named type. This is used for builtin types, and to add an + // imported type to the global scope. + Named_object* + add_named_type(Named_type* named_type); + + // Add a type declaration. + Named_object* + add_type_declaration(const std::string& name, const Package* package, + source_location location) + { + Named_object* no = Named_object::make_type_declaration(name, package, + location); + return this->add_named_object(no); + } + + // Add a variable. + Named_object* + add_variable(const std::string& name, const Package* package, + Variable* variable) + { + return this->add_named_object(Named_object::make_variable(name, package, + variable)); + } + + // Add a result variable. + Named_object* + add_result_variable(const std::string& name, Result_variable* result) + { + return this->add_named_object(Named_object::make_result_variable(name, + result)); + } + + // Add a function. + Named_object* + add_function(const std::string& name, const Package*, Function* function); + + // Add a function declaration. + Named_object* + add_function_declaration(const std::string& name, const Package* package, + Function_type* type, source_location location); + + // Add a package. The location is the location of the import + // statement. + Named_object* + add_package(const std::string& alias, Package* package) + { + Named_object* no = Named_object::make_package(alias, package); + return this->add_named_object(no); + } + + // Define a type which was already declared. + void + define_type(Named_object*, Named_type*); + + // Add a method to the list of objects. This is not added to the + // lookup table. + void + add_method(Named_object*); + + // Add a named object to this binding. + Named_object* + add_named_object(Named_object* no) + { return this->add_named_object_to_contour(&this->bindings_, no); } + + // Clear all names in file scope from the bindings. + void + clear_file_scope(); + + // Look up a name in this binding contour and in any enclosing + // binding contours. This returns NULL if the name is not found. + Named_object* + lookup(const std::string&) const; + + // Look up a name in this binding contour without looking in any + // enclosing binding contours. Returns NULL if the name is not found. + Named_object* + lookup_local(const std::string&) const; + + // Remove a name. + void + remove_binding(Named_object*); + + // Traverse the tree. See the Traverse class. + int + traverse(Traverse*, bool is_global); + + // Iterate over definitions. This does not include things which + // were only declared. + + typedef std::vector<Named_object*>::const_iterator + const_definitions_iterator; + + const_definitions_iterator + begin_definitions() const + { return this->named_objects_.begin(); } + + const_definitions_iterator + end_definitions() const + { return this->named_objects_.end(); } + + // Return the number of definitions. + size_t + size_definitions() const + { return this->named_objects_.size(); } + + // Return whether there are no definitions. + bool + empty_definitions() const + { return this->named_objects_.empty(); } + + // Iterate over declarations. This is everything that has been + // declared, which includes everything which has been defined. + + typedef Contour::const_iterator const_declarations_iterator; + + const_declarations_iterator + begin_declarations() const + { return this->bindings_.begin(); } + + const_declarations_iterator + end_declarations() const + { return this->bindings_.end(); } + + // Return the number of declarations. + size_t + size_declarations() const + { return this->bindings_.size(); } + + // Return whether there are no declarations. + bool + empty_declarations() const + { return this->bindings_.empty(); } + + // Return the first declaration. + Named_object* + first_declaration() + { return this->bindings_.empty() ? NULL : this->bindings_.begin()->second; } + + private: + Named_object* + add_named_object_to_contour(Contour*, Named_object*); + + Named_object* + new_definition(Named_object*, Named_object*); + + // Enclosing bindings. + Bindings* enclosing_; + // The list of objects. + std::vector<Named_object*> named_objects_; + // The mapping from names to objects. + Contour bindings_; +}; + +// A label. + +class Label +{ + public: + Label(const std::string& name) + : name_(name), location_(0), decl_(NULL) + { } + + // Return the label's name. + const std::string& + name() const + { return this->name_; } + + // Return whether the label has been defined. + bool + is_defined() const + { return this->location_ != 0; } + + // Return the location of the definition. + source_location + location() const + { return this->location_; } + + // Define the label at LOCATION. + void + define(source_location location) + { + gcc_assert(this->location_ == 0); + this->location_ = location; + } + + // Return the LABEL_DECL for this decl. + tree + get_decl(); + + // Return an expression for the address of this label. + tree + get_addr(source_location location); + + private: + // The name of the label. + std::string name_; + // The location of the definition. This is 0 if the label has not + // yet been defined. + source_location location_; + // The LABEL_DECL. + tree decl_; +}; + +// An unnamed label. These are used when lowering loops. + +class Unnamed_label +{ + public: + Unnamed_label(source_location location) + : location_(location), decl_(NULL) + { } + + // Get the location where the label is defined. + source_location + location() const + { return this->location_; } + + // Set the location where the label is defined. + void + set_location(source_location location) + { this->location_ = location; } + + // Return a statement which defines this label. + tree + get_definition(); + + // Return a goto to this label from LOCATION. + tree + get_goto(source_location location); + + private: + // Return the LABEL_DECL to use with GOTO_EXPR. + tree + get_decl(); + + // The location where the label is defined. + source_location location_; + // The LABEL_DECL. + tree decl_; +}; + +// An imported package. + +class Package +{ + public: + Package(const std::string& name, const std::string& unique_prefix, + source_location location); + + // The real name of this package. This may be different from the + // name in the associated Named_object if the import statement used + // an alias. + const std::string& + name() const + { return this->name_; } + + // Return the location of the import statement. + source_location + location() const + { return this->location_; } + + // Get the unique prefix used for all symbols exported from this + // package. + const std::string& + unique_prefix() const + { + gcc_assert(!this->unique_prefix_.empty()); + return this->unique_prefix_; + } + + // The priority of this package. The init function of packages with + // lower priority must be run before the init function of packages + // with higher priority. + int + priority() const + { return this->priority_; } + + // Set the priority. + void + set_priority(int priority); + + // Return the bindings. + Bindings* + bindings() + { return this->bindings_; } + + // Whether some symbol from the package was used. + bool + used() const + { return this->used_; } + + // Note that some symbol from this package was used. + void + set_used() const + { this->used_ = true; } + + // Clear the used field for the next file. + void + clear_used() + { this->used_ = false; } + + // Whether this package was imported in the current file. + bool + is_imported() const + { return this->is_imported_; } + + // Note that this package was imported in the current file. + void + set_is_imported() + { this->is_imported_ = true; } + + // Clear the imported field for the next file. + void + clear_is_imported() + { this->is_imported_ = false; } + + // Whether this package was imported with a name of "_". + bool + uses_sink_alias() const + { return this->uses_sink_alias_; } + + // Note that this package was imported with a name of "_". + void + set_uses_sink_alias() + { this->uses_sink_alias_ = true; } + + // Clear the sink alias field for the next file. + void + clear_uses_sink_alias() + { this->uses_sink_alias_ = false; } + + // Look up a name in the package. Returns NULL if the name is not + // found. + Named_object* + lookup(const std::string& name) const + { return this->bindings_->lookup(name); } + + // Set the location of the package. This is used if it is seen in a + // different import before it is really imported. + void + set_location(source_location location) + { this->location_ = location; } + + // Add a constant to the package. + Named_object* + add_constant(const Typed_identifier& tid, Expression* expr) + { return this->bindings_->add_constant(tid, this, expr, 0); } + + // Add a type to the package. + Named_object* + add_type(const std::string& name, Type* type, source_location location) + { return this->bindings_->add_type(name, this, type, location); } + + // Add a type declaration to the package. + Named_object* + add_type_declaration(const std::string& name, source_location location) + { return this->bindings_->add_type_declaration(name, this, location); } + + // Add a variable to the package. + Named_object* + add_variable(const std::string& name, Variable* variable) + { return this->bindings_->add_variable(name, this, variable); } + + // Add a function declaration to the package. + Named_object* + add_function_declaration(const std::string& name, Function_type* type, + source_location loc) + { return this->bindings_->add_function_declaration(name, this, type, loc); } + + // Determine types of constants. + void + determine_types(); + + private: + // The real name of this package. + std::string name_; + // The unique prefix for all exported global symbols. + std::string unique_prefix_; + // The names in this package. + Bindings* bindings_; + // The priority of this package. A package has a priority higher + // than the priority of all of the packages that it imports. This + // is used to run init functions in the right order. + int priority_; + // The location of the import statement. + source_location location_; + // True if some name from this package was used. This is mutable + // because we can use a package even if we have a const pointer to + // it. + mutable bool used_; + // True if this package was imported in the current file. + bool is_imported_; + // True if this package was imported with a name of "_". + bool uses_sink_alias_; +}; + +// Return codes for the traversal functions. This is not an enum +// because we want to be able to declare traversal functions in other +// header files without including this one. + +// Continue traversal as usual. +const int TRAVERSE_CONTINUE = -1; + +// Exit traversal. +const int TRAVERSE_EXIT = 0; + +// Continue traversal, but skip components of the current object. +// E.g., if this is returned by Traverse::statement, we do not +// traverse the expressions in the statement even if +// traverse_expressions is set in the traverse_mask. +const int TRAVERSE_SKIP_COMPONENTS = 1; + +// This class is used when traversing the parse tree. The caller uses +// a subclass which overrides functions as desired. + +class Traverse +{ + public: + // These bitmasks say what to traverse. + static const unsigned int traverse_variables = 0x1; + static const unsigned int traverse_constants = 0x2; + static const unsigned int traverse_functions = 0x4; + static const unsigned int traverse_blocks = 0x8; + static const unsigned int traverse_statements = 0x10; + static const unsigned int traverse_expressions = 0x20; + static const unsigned int traverse_types = 0x40; + + Traverse(unsigned int traverse_mask) + : traverse_mask_(traverse_mask), types_seen_(NULL), expressions_seen_(NULL) + { } + + virtual ~Traverse(); + + // The bitmask of what to traverse. + unsigned int + traverse_mask() const + { return this->traverse_mask_; } + + // Record that we are going to traverse a type. This returns true + // if the type has already been seen in this traversal. This is + // required because types, unlike expressions, can form a circular + // graph. + bool + remember_type(const Type*); + + // Record that we are going to see an expression. This returns true + // if the expression has already been seen in this traversal. This + // is only needed for cases where multiple expressions can point to + // a single one. + bool + remember_expression(const Expression*); + + // These functions return one of the TRAVERSE codes defined above. + + // If traverse_variables is set in the mask, this is called for + // every variable in the tree. + virtual int + variable(Named_object*); + + // If traverse_constants is set in the mask, this is called for + // every named constant in the tree. The bool parameter is true for + // a global constant. + virtual int + constant(Named_object*, bool); + + // If traverse_functions is set in the mask, this is called for + // every function in the tree. + virtual int + function(Named_object*); + + // If traverse_blocks is set in the mask, this is called for every + // block in the tree. + virtual int + block(Block*); + + // If traverse_statements is set in the mask, this is called for + // every statement in the tree. + virtual int + statement(Block*, size_t* index, Statement*); + + // If traverse_expressions is set in the mask, this is called for + // every expression in the tree. + virtual int + expression(Expression**); + + // If traverse_types is set in the mask, this is called for every + // type in the tree. + virtual int + type(Type*); + + private: + typedef Unordered_set_hash(const Type*, Type_hash_identical, + Type_identical) Types_seen; + + typedef Unordered_set(const Expression*) Expressions_seen; + + // Bitmask of what sort of objects to traverse. + unsigned int traverse_mask_; + // Types which have been seen in this traversal. + Types_seen* types_seen_; + // Expressions which have been seen in this traversal. + Expressions_seen* expressions_seen_; +}; + +// When translating the gogo IR into trees, this is the context we +// pass down the blocks and statements. + +class Translate_context +{ + public: + Translate_context(Gogo* gogo, Named_object* function, Block* block, + tree block_tree) + : gogo_(gogo), function_(function), block_(block), block_tree_(block_tree), + is_const_(false) + { } + + // Accessors. + + Gogo* + gogo() + { return this->gogo_; } + + Named_object* + function() + { return this->function_; } + + Block* + block() + { return this->block_; } + + tree + block_tree() + { return this->block_tree_; } + + bool + is_const() + { return this->is_const_; } + + // Make a constant context. + void + set_is_const() + { this->is_const_ = true; } + + private: + // The IR for the entire compilation unit. + Gogo* gogo_; + // The function we are currently translating. + Named_object* function_; + // The block we are currently translating. + Block *block_; + // The BLOCK node for the current block. + tree block_tree_; + // Whether this is being evaluated in a constant context. This is + // used for type descriptor initializers. + bool is_const_; +}; + +// Runtime error codes. These must match the values in +// libgo/runtime/go-runtime-error.c. + +// Slice index out of bounds: negative or larger than the length of +// the slice. +static const int RUNTIME_ERROR_SLICE_INDEX_OUT_OF_BOUNDS = 0; + +// Array index out of bounds. +static const int RUNTIME_ERROR_ARRAY_INDEX_OUT_OF_BOUNDS = 1; + +// String index out of bounds. +static const int RUNTIME_ERROR_STRING_INDEX_OUT_OF_BOUNDS = 2; + +// Slice slice out of bounds: negative or larger than the length of +// the slice or high bound less than low bound. +static const int RUNTIME_ERROR_SLICE_SLICE_OUT_OF_BOUNDS = 3; + +// Array slice out of bounds. +static const int RUNTIME_ERROR_ARRAY_SLICE_OUT_OF_BOUNDS = 4; + +// String slice out of bounds. +static const int RUNTIME_ERROR_STRING_SLICE_OUT_OF_BOUNDS = 5; + +// Dereference of nil pointer. This is used when there is a +// dereference of a pointer to a very large struct or array, to ensure +// that a gigantic array is not used a proxy to access random memory +// locations. +static const int RUNTIME_ERROR_NIL_DEREFERENCE = 6; + +// Slice length or capacity out of bounds in make: negative or +// overflow or length greater than capacity. +static const int RUNTIME_ERROR_MAKE_SLICE_OUT_OF_BOUNDS = 7; + +// Map capacity out of bounds in make: negative or overflow. +static const int RUNTIME_ERROR_MAKE_MAP_OUT_OF_BOUNDS = 8; + +// Channel capacity out of bounds in make: negative or overflow. +static const int RUNTIME_ERROR_MAKE_CHAN_OUT_OF_BOUNDS = 9; + +// This is used by some of the langhooks. +extern Gogo* go_get_gogo(); + +// Whether we have seen any errors. FIXME: Replace with a backend +// interface. +extern bool saw_errors(); + +#endif // !defined(GO_GOGO_H) diff --git a/gcc/go/gofrontend/import-archive.cc b/gcc/go/gofrontend/import-archive.cc new file mode 100644 index 000000000..07ac01a44 --- /dev/null +++ b/gcc/go/gofrontend/import-archive.cc @@ -0,0 +1,661 @@ +// import-archive.cc -- Go frontend read import data from an archive file. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include "import.h" + +#ifndef O_BINARY +#define O_BINARY 0 +#endif + +// Archive magic numbers. + +static const char armag[] = +{ + '!', '<', 'a', 'r', 'c', 'h', '>', '\n' +}; + +static const char armagt[] = +{ + '!', '<', 't', 'h', 'i', 'n', '>', '\n' +}; + +static const char arfmag[2] = { '`', '\n' }; + +// The header of an entry in an archive. This is all readable text, +// padded with spaces where necesary. + +struct Archive_header +{ + // The entry name. + char ar_name[16]; + // The file modification time. + char ar_date[12]; + // The user's UID in decimal. + char ar_uid[6]; + // The user's GID in decimal. + char ar_gid[6]; + // The file mode in octal. + char ar_mode[8]; + // The file size in decimal. + char ar_size[10]; + // The final magic code. + char ar_fmag[2]; +}; + +// The functions in this file extract Go export data from an archive. + +const int Import::archive_magic_len; + +// Return true if BYTES, which are from the start of the file, are an +// archive magic number. + +bool +Import::is_archive_magic(const char* bytes) +{ + return (memcmp(bytes, armag, Import::archive_magic_len) == 0 + || memcmp(bytes, armagt, Import::archive_magic_len) == 0); +} + +// An object used to read an archive file. + +class Archive_file +{ + public: + Archive_file(const std::string& filename, int fd, source_location location) + : filename_(filename), fd_(fd), filesize_(-1), extended_names_(), + is_thin_archive_(false), location_(location), nested_archives_() + { } + + // Initialize. + bool + initialize(); + + // Return the file name. + const std::string& + filename() const + { return this->filename_; } + + // Get the file size. + off_t + filesize() const + { return this->filesize_; } + + // Return whether this is a thin archive. + bool + is_thin_archive() const + { return this->is_thin_archive_; } + + // Return the location of the import statement. + source_location + location() const + { return this->location_; } + + // Read bytes. + bool + read(off_t offset, off_t size, char*); + + // Read the archive header at OFF, setting *PNAME, *SIZE, and + // *NESTED_OFF. + bool + read_header(off_t off, std::string* pname, off_t* size, off_t* nested_off); + + // Interpret the header of HDR, the header of the archive member at + // file offset OFF. Return whether it succeeded. Set *SIZE to the + // size of the member. Set *PNAME to the name of the member. Set + // *NESTED_OFF to the offset in a nested archive. + bool + interpret_header(const Archive_header* hdr, off_t off, + std::string* pname, off_t* size, off_t* nested_off) const; + + // Get the file and offset for an archive member. + bool + get_file_and_offset(off_t off, const std::string& hdrname, + off_t nested_off, int* memfd, off_t* memoff, + std::string* memname); + + private: + // For keeping track of open nested archives in a thin archive file. + typedef std::map<std::string, Archive_file*> Nested_archive_table; + + // The name of the file. + std::string filename_; + // The file descriptor. + int fd_; + // The file size; + off_t filesize_; + // The extended name table. + std::string extended_names_; + // Whether this is a thin archive. + bool is_thin_archive_; + // The location of the import statements. + source_location location_; + // Table of nested archives. + Nested_archive_table nested_archives_; +}; + +bool +Archive_file::initialize() +{ + struct stat st; + if (fstat(this->fd_, &st) < 0) + { + error_at(this->location_, "%s: %m", this->filename_.c_str()); + return false; + } + this->filesize_ = st.st_size; + + char buf[sizeof(armagt)]; + if (::lseek(this->fd_, 0, SEEK_SET) < 0 + || ::read(this->fd_, buf, sizeof(armagt)) != sizeof(armagt)) + { + error_at(this->location_, "%s: %m", this->filename_.c_str()); + return false; + } + this->is_thin_archive_ = memcmp(buf, armagt, sizeof(armagt)) == 0; + + if (this->filesize_ == sizeof(armag)) + { + // Empty archive. + return true; + } + + // Look for the extended name table. + std::string filename; + off_t size; + if (!this->read_header(sizeof(armagt), &filename, &size, NULL)) + return false; + if (filename.empty()) + { + // We found the symbol table. + off_t off = sizeof(armagt) + sizeof(Archive_header) + size; + if ((off & 1) != 0) + ++off; + if (!this->read_header(off, &filename, &size, NULL)) + filename.clear(); + } + if (filename == "/") + { + char* rdbuf = new char[size]; + if (::read(this->fd_, rdbuf, size) != size) + { + error_at(this->location_, "%s: could not read extended names", + filename.c_str()); + delete[] rdbuf; + return false; + } + this->extended_names_.assign(rdbuf, size); + delete[] rdbuf; + } + + return true; +} + +// Read bytes from the file. + +bool +Archive_file::read(off_t offset, off_t size, char* buf) +{ + if (::lseek(this->fd_, offset, SEEK_SET) < 0 + || ::read(this->fd_, buf, size) != size) + { + error_at(this->location_, "%s: %m", this->filename_.c_str()); + return false; + } + return true; +} + +// Read the header at OFF. Set *PNAME to the name, *SIZE to the size, +// and *NESTED_OFF to the nested offset. + +bool +Archive_file::read_header(off_t off, std::string* pname, off_t* size, + off_t* nested_off) +{ + Archive_header hdr; + if (::lseek(this->fd_, off, SEEK_SET) < 0) + { + error_at(this->location_, "%s: %m", this->filename_.c_str()); + return false; + } + ssize_t got = ::read(this->fd_, &hdr, sizeof hdr); + if (got != sizeof hdr) + { + if (got < 0) + error_at(this->location_, "%s: %m", this->filename_.c_str()); + else if (got > 0) + error_at(this->location_, "%s: short archive header at %ld", + this->filename_.c_str(), static_cast<long>(off)); + else + error_at(this->location_, "%s: unexpected EOF at %ld", + this->filename_.c_str(), static_cast<long>(off)); + } + off_t local_nested_off; + if (!this->interpret_header(&hdr, off, pname, size, &local_nested_off)) + return false; + if (nested_off != NULL) + *nested_off = local_nested_off; + return true; +} + +// Interpret the header of HDR, the header of the archive member at +// file offset OFF. + +bool +Archive_file::interpret_header(const Archive_header* hdr, off_t off, + std::string* pname, off_t* size, + off_t* nested_off) const +{ + if (memcmp(hdr->ar_fmag, arfmag, sizeof arfmag) != 0) + { + error_at(this->location_, "%s: malformed archive header at %lu", + this->filename_.c_str(), static_cast<unsigned long>(off)); + return false; + } + + const int size_string_size = sizeof hdr->ar_size; + char size_string[size_string_size + 1]; + memcpy(size_string, hdr->ar_size, size_string_size); + char* ps = size_string + size_string_size; + while (ps[-1] == ' ') + --ps; + *ps = '\0'; + + errno = 0; + char* end; + *size = strtol(size_string, &end, 10); + if (*end != '\0' + || *size < 0 + || (*size == LONG_MAX && errno == ERANGE)) + { + error_at(this->location_, "%s: malformed archive header size at %lu", + this->filename_.c_str(), static_cast<unsigned long>(off)); + return false; + } + + if (hdr->ar_name[0] != '/') + { + const char* name_end = strchr(hdr->ar_name, '/'); + if (name_end == NULL + || name_end - hdr->ar_name >= static_cast<int>(sizeof hdr->ar_name)) + { + error_at(this->location_, "%s: malformed archive header name at %lu", + this->filename_.c_str(), static_cast<unsigned long>(off)); + return false; + } + pname->assign(hdr->ar_name, name_end - hdr->ar_name); + *nested_off = 0; + } + else if (hdr->ar_name[1] == ' ') + { + // This is the symbol table. + pname->clear(); + } + else if (hdr->ar_name[1] == '/') + { + // This is the extended name table. + pname->assign(1, '/'); + } + else + { + errno = 0; + long x = strtol(hdr->ar_name + 1, &end, 10); + long y = 0; + if (*end == ':') + y = strtol(end + 1, &end, 10); + if (*end != ' ' + || x < 0 + || (x == LONG_MAX && errno == ERANGE) + || static_cast<size_t>(x) >= this->extended_names_.size()) + { + error_at(this->location_, "%s: bad extended name index at %lu", + this->filename_.c_str(), static_cast<unsigned long>(off)); + return false; + } + + const char* name = this->extended_names_.data() + x; + const char* name_end = strchr(name, '\n'); + if (static_cast<size_t>(name_end - name) > this->extended_names_.size() + || name_end[-1] != '/') + { + error_at(this->location_, "%s: bad extended name entry at header %lu", + this->filename_.c_str(), static_cast<unsigned long>(off)); + return false; + } + pname->assign(name, name_end - 1 - name); + if (nested_off != NULL) + *nested_off = y; + } + + return true; +} + +// Get the file and offset for an archive member. + +bool +Archive_file::get_file_and_offset(off_t off, const std::string& hdrname, + off_t nested_off, int* memfd, off_t* memoff, + std::string* memname) +{ + if (!this->is_thin_archive_) + { + *memfd = this->fd_; + *memoff = off + sizeof(Archive_header); + *memname = this->filename_ + '(' + hdrname + ')'; + return true; + } + + std::string filename = hdrname; + if (!IS_ABSOLUTE_PATH(filename.c_str())) + { + const char* archive_path = this->filename_.c_str(); + const char* basename = lbasename(archive_path); + if (basename > archive_path) + filename.replace(0, 0, + this->filename_.substr(0, basename - archive_path)); + } + + if (nested_off > 0) + { + // This is a member of a nested archive. + Archive_file* nfile; + Nested_archive_table::const_iterator p = + this->nested_archives_.find(filename); + if (p != this->nested_archives_.end()) + nfile = p->second; + else + { + int nfd = open(filename.c_str(), O_RDONLY | O_BINARY); + if (nfd < 0) + { + error_at(this->location_, "%s: can't open nested archive %s", + this->filename_.c_str(), filename.c_str()); + return false; + } + nfile = new Archive_file(filename, nfd, this->location_); + if (!nfile->initialize()) + { + delete nfile; + return false; + } + this->nested_archives_[filename] = nfile; + } + + std::string nname; + off_t nsize; + off_t nnested_off; + if (!nfile->read_header(nested_off, &nname, &nsize, &nnested_off)) + return false; + return nfile->get_file_and_offset(nested_off, nname, nnested_off, + memfd, memoff, memname); + } + + // An external member of a thin archive. + *memfd = open(filename.c_str(), O_RDONLY | O_BINARY); + if (*memfd < 0) + { + error_at(this->location_, "%s: %m", filename.c_str()); + return false; + } + *memoff = 0; + *memname = filename; + return true; +} + +// An archive member iterator. This is more-or-less copied from gold. + +class Archive_iterator +{ + public: + // The header of an archive member. This is what this iterator + // points to. + struct Header + { + // The name of the member. + std::string name; + // The file offset of the member. + off_t off; + // The file offset of a nested archive member. + off_t nested_off; + // The size of the member. + off_t size; + }; + + Archive_iterator(Archive_file* afile, off_t off) + : afile_(afile), off_(off) + { this->read_next_header(); } + + const Header& + operator*() const + { return this->header_; } + + const Header* + operator->() const + { return &this->header_; } + + Archive_iterator& + operator++() + { + if (this->off_ == this->afile_->filesize()) + return *this; + this->off_ += sizeof(Archive_header); + if (!this->afile_->is_thin_archive()) + this->off_ += this->header_.size; + if ((this->off_ & 1) != 0) + ++this->off_; + this->read_next_header(); + return *this; + } + + Archive_iterator + operator++(int) + { + Archive_iterator ret = *this; + ++*this; + return ret; + } + + bool + operator==(const Archive_iterator p) const + { return this->off_ == p->off; } + + bool + operator!=(const Archive_iterator p) const + { return this->off_ != p->off; } + + private: + void + read_next_header(); + + // The underlying archive file. + Archive_file* afile_; + // The current offset in the file. + off_t off_; + // The current archive header. + Header header_; +}; + +// Read the next archive header. + +void +Archive_iterator::read_next_header() +{ + off_t filesize = this->afile_->filesize(); + while (true) + { + if (filesize - this->off_ < static_cast<off_t>(sizeof(Archive_header))) + { + if (filesize != this->off_) + { + error_at(this->afile_->location(), + "%s: short archive header at %lu", + this->afile_->filename().c_str(), + static_cast<unsigned long>(this->off_)); + this->off_ = filesize; + } + this->header_.off = filesize; + return; + } + + char buf[sizeof(Archive_header)]; + if (!this->afile_->read(this->off_, sizeof(Archive_header), buf)) + { + this->header_.off = filesize; + return; + } + + const Archive_header* hdr = reinterpret_cast<const Archive_header*>(buf); + if (!this->afile_->interpret_header(hdr, this->off_, &this->header_.name, + &this->header_.size, + &this->header_.nested_off)) + { + this->header_.off = filesize; + return; + } + this->header_.off = this->off_; + + // Skip special members. + if (!this->header_.name.empty() && this->header_.name != "/") + return; + + this->off_ += sizeof(Archive_header) + this->header_.size; + if ((this->off_ & 1) != 0) + ++this->off_; + } +} + +// Initial iterator. + +Archive_iterator +archive_begin(Archive_file* afile) +{ + return Archive_iterator(afile, sizeof(armag)); +} + +// Final iterator. + +Archive_iterator +archive_end(Archive_file* afile) +{ + return Archive_iterator(afile, afile->filesize()); +} + +// A type of Import_stream which concatenates other Import_streams +// together. + +class Stream_concatenate : public Import::Stream +{ + public: + Stream_concatenate() + : inputs_() + { } + + // Add a new stream. + void + add(Import::Stream* is) + { this->inputs_.push_back(is); } + + protected: + bool + do_peek(size_t, const char**); + + void + do_advance(size_t); + + private: + std::list<Import::Stream*> inputs_; +}; + +// Peek ahead. + +bool +Stream_concatenate::do_peek(size_t length, const char** bytes) +{ + while (true) + { + if (this->inputs_.empty()) + return false; + if (this->inputs_.front()->peek(length, bytes)) + return true; + delete this->inputs_.front(); + this->inputs_.pop_front(); + } +} + +// Advance. + +void +Stream_concatenate::do_advance(size_t skip) +{ + while (true) + { + if (this->inputs_.empty()) + return; + if (!this->inputs_.front()->at_eof()) + { + // We just assume that this will do the right thing. It + // should be OK since we should never want to skip past + // multiple streams. + this->inputs_.front()->advance(skip); + return; + } + delete this->inputs_.front(); + this->inputs_.pop_front(); + } +} + +// Import data from an archive. We walk through the archive and +// import data from each member. + +Import::Stream* +Import::find_archive_export_data(const std::string& filename, int fd, + source_location location) +{ + Archive_file afile(filename, fd, location); + if (!afile.initialize()) + return NULL; + + Stream_concatenate* ret = new Stream_concatenate; + + bool any_data = false; + bool any_members = false; + Archive_iterator pend = archive_end(&afile); + for (Archive_iterator p = archive_begin(&afile); p != pend; p++) + { + any_members = true; + int member_fd; + off_t member_off; + std::string member_name; + if (!afile.get_file_and_offset(p->off, p->name, p->nested_off, + &member_fd, &member_off, &member_name)) + return NULL; + + Import::Stream* is = Import::find_object_export_data(member_name, + member_fd, + member_off, + location); + if (is != NULL) + { + ret->add(is); + any_data = true; + } + } + + if (!any_members) + { + // It's normal to have an empty archive file when using gobuild. + return new Stream_from_string(""); + } + + if (!any_data) + { + delete ret; + return NULL; + } + + return ret; +} diff --git a/gcc/go/gofrontend/import.cc b/gcc/go/gofrontend/import.cc new file mode 100644 index 000000000..d926edf44 --- /dev/null +++ b/gcc/go/gofrontend/import.cc @@ -0,0 +1,892 @@ +// import.cc -- Go frontend import declarations. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include "filenames.h" +#include "simple-object.h" + +#include "go-c.h" +#include "gogo.h" +#include "types.h" +#include "export.h" +#include "import.h" + +#ifndef O_BINARY +#define O_BINARY 0 +#endif + +// The list of paths we search for import files. + +static std::vector<std::string> search_path; + +// Add a directory to the search path. This is called from the option +// handling language hook. + +GO_EXTERN_C +void +go_add_search_path(const char* path) +{ + search_path.push_back(std::string(path)); +} + +// The name used for parameters, receivers, and results in imported +// function types. + +const char* const Import::import_marker = "*imported*"; + +// Find import data. This searches the file system for FILENAME and +// returns a pointer to a Stream object to read the data that it +// exports. If the file is not found, it returns NULL. + +// When FILENAME is not an absolute path, we use the search path +// provided by -I and -L options. + +// When FILENAME does not exist, we try modifying FILENAME to find the +// file. We use the first of these which exists: +// * We append ".gox". +// * We turn the base of FILENAME into libFILENAME.so. +// * We turn the base of FILENAME into libFILENAME.a. +// * We append ".o". + +// When using a search path, we apply each of these transformations at +// each entry on the search path before moving on to the next entry. +// If the file exists, but does not contain any Go export data, we +// stop; we do not keep looking for another file with the same name +// later in the search path. + +Import::Stream* +Import::open_package(const std::string& filename, source_location location) +{ + if (!IS_ABSOLUTE_PATH(filename)) + { + for (std::vector<std::string>::const_iterator p = search_path.begin(); + p != search_path.end(); + ++p) + { + std::string indir = *p; + if (!indir.empty() && indir[indir.size() - 1] != '/') + indir += '/'; + indir += filename; + Stream* s = Import::try_package_in_directory(indir, location); + if (s != NULL) + return s; + } + } + + Stream* s = Import::try_package_in_directory(filename, location); + if (s != NULL) + return s; + + return NULL; +} + +// Try to find the export data for FILENAME. + +Import::Stream* +Import::try_package_in_directory(const std::string& filename, + source_location location) +{ + std::string found_filename = filename; + int fd = open(found_filename.c_str(), O_RDONLY | O_BINARY); + + if (fd >= 0) + { + struct stat s; + if (fstat(fd, &s) >= 0 && S_ISDIR(s.st_mode)) + { + close(fd); + fd = -1; + errno = EISDIR; + } + } + + if (fd < 0) + { + if (errno != ENOENT && errno != EISDIR) + warning_at(location, 0, "%s: %m", filename.c_str()); + + fd = Import::try_suffixes(&found_filename); + if (fd < 0) + return NULL; + } + + // The export data may not be in this file. + Stream* s = Import::find_export_data(found_filename, fd, location); + if (s != NULL) + return s; + + close(fd); + + error_at(location, "%s exists but does not contain any Go export data", + found_filename.c_str()); + + return NULL; +} + +// Given import "*PFILENAME", where *PFILENAME does not exist, try +// various suffixes. If we find one, set *PFILENAME to the one we +// found. Return the open file descriptor. + +int +Import::try_suffixes(std::string* pfilename) +{ + std::string filename = *pfilename + ".gox"; + int fd = open(filename.c_str(), O_RDONLY | O_BINARY); + if (fd >= 0) + { + *pfilename = filename; + return fd; + } + + const char* basename = lbasename(pfilename->c_str()); + size_t basename_pos = basename - pfilename->c_str(); + filename = pfilename->substr(0, basename_pos) + "lib" + basename + ".so"; + fd = open(filename.c_str(), O_RDONLY | O_BINARY); + if (fd >= 0) + { + *pfilename = filename; + return fd; + } + + filename = pfilename->substr(0, basename_pos) + "lib" + basename + ".a"; + fd = open(filename.c_str(), O_RDONLY | O_BINARY); + if (fd >= 0) + { + *pfilename = filename; + return fd; + } + + filename = *pfilename + ".o"; + fd = open(filename.c_str(), O_RDONLY | O_BINARY); + if (fd >= 0) + { + *pfilename = filename; + return fd; + } + + return -1; +} + +// Look for export data in the file descriptor FD. + +Import::Stream* +Import::find_export_data(const std::string& filename, int fd, + source_location location) +{ + // See if we can read this as an object file. + Import::Stream* stream = Import::find_object_export_data(filename, fd, 0, + location); + if (stream != NULL) + return stream; + + const int len = MAX(Export::v1_magic_len, Import::archive_magic_len); + + if (lseek(fd, 0, SEEK_SET) < 0) + { + error_at(location, "lseek %s failed: %m", filename.c_str()); + return NULL; + } + + char buf[len]; + ssize_t c = read(fd, buf, len); + if (c < len) + return NULL; + + // Check for a file containing nothing but Go export data. + if (memcmp(buf, Export::v1_magic, Export::v1_magic_len) == 0) + return new Stream_from_file(fd); + + // See if we can read this as an archive. + if (Import::is_archive_magic(buf)) + return Import::find_archive_export_data(filename, fd, location); + + return NULL; +} + +// Look for export data in a simple_object. + +Import::Stream* +Import::find_object_export_data(const std::string& filename, + int fd, + off_t offset, + source_location location) +{ + const char* errmsg; + int err; + simple_object_read* sobj = simple_object_start_read(fd, offset, + "__GNU_GO", + &errmsg, &err); + if (sobj == NULL) + return NULL; + + off_t sec_offset; + off_t sec_length; + int found = simple_object_find_section(sobj, ".go_export", &sec_offset, + &sec_length, &errmsg, &err); + + simple_object_release_read(sobj); + + if (!found) + return NULL; + + if (lseek(fd, offset + sec_offset, SEEK_SET) < 0) + { + error_at(location, "lseek %s failed: %m", filename.c_str()); + return NULL; + } + + char* buf = new char[sec_length]; + ssize_t c = read(fd, buf, sec_length); + if (c < 0) + { + error_at(location, "read %s failed: %m", filename.c_str()); + delete[] buf; + return NULL; + } + if (c < sec_length) + { + error_at(location, "%s: short read", filename.c_str()); + delete[] buf; + return NULL; + } + + return new Stream_from_buffer(buf, sec_length); +} + +// Class Import. + +// Construct an Import object. We make the builtin_types_ vector +// large enough to hold all the builtin types. + +Import::Import(Stream* stream, source_location location) + : gogo_(NULL), stream_(stream), location_(location), package_(NULL), + add_to_globals_(false), + builtin_types_((- SMALLEST_BUILTIN_CODE) + 1), + types_() +{ +} + +// Import the data in the associated stream. + +Package* +Import::import(Gogo* gogo, const std::string& local_name, + bool is_local_name_exported) +{ + // Hold on to the Gogo structure. Otherwise we need to pass it + // through all the import functions, because we need it when reading + // a type. + this->gogo_ = gogo; + + // A stream of export data can include data from more than one input + // file. Here we loop over each input file. + Stream* stream = this->stream_; + while (!stream->at_eof() && !stream->saw_error()) + { + // The vector of types is package specific. + this->types_.clear(); + + stream->require_bytes(this->location_, Export::v1_magic, + Export::v1_magic_len); + + this->require_c_string("package "); + std::string package_name = this->read_identifier(); + this->require_c_string(";\n"); + + this->require_c_string("prefix "); + std::string unique_prefix = this->read_identifier(); + this->require_c_string(";\n"); + + this->package_ = gogo->add_imported_package(package_name, local_name, + is_local_name_exported, + unique_prefix, + this->location_, + &this->add_to_globals_); + if (this->package_ == NULL) + { + stream->set_saw_error(); + return NULL; + } + + this->require_c_string("priority "); + std::string priority_string = this->read_identifier(); + int prio; + if (!this->string_to_int(priority_string, false, &prio)) + return NULL; + this->package_->set_priority(prio); + this->require_c_string(";\n"); + + if (stream->match_c_string("import ")) + this->read_import_init_fns(gogo); + + // Loop over all the input data for this package. + while (!stream->saw_error()) + { + if (stream->match_c_string("const ")) + this->import_const(); + else if (stream->match_c_string("type ")) + this->import_type(); + else if (stream->match_c_string("var ")) + this->import_var(); + else if (stream->match_c_string("func ")) + this->import_func(this->package_); + else if (stream->match_c_string("checksum ")) + break; + else + { + error_at(this->location_, + ("error in import data at %d: " + "expected %<const%>, %<type%>, %<var%>, " + "%<func%>, or %<checksum%>"), + stream->pos()); + stream->set_saw_error(); + return NULL; + } + } + + // We currently ignore the checksum. In the future we could + // store the checksum somewhere in the generated object and then + // verify that the checksum matches at link time or at dynamic + // load time. + this->require_c_string("checksum "); + stream->advance(Export::v1_checksum_len * 2); + this->require_c_string(";\n"); + } + + return this->package_; +} + +// Read the list of import control functions. + +void +Import::read_import_init_fns(Gogo* gogo) +{ + this->require_c_string("import"); + while (!this->match_c_string(";")) + { + this->require_c_string(" "); + std::string package_name = this->read_identifier(); + this->require_c_string(" "); + std::string init_name = this->read_identifier(); + this->require_c_string(" "); + std::string prio_string = this->read_identifier(); + int prio; + if (!this->string_to_int(prio_string, false, &prio)) + return; + gogo->add_import_init_fn(package_name, init_name, prio); + } + this->require_c_string(";\n"); +} + +// Import a constant. + +void +Import::import_const() +{ + std::string name; + Type* type; + Expression* expr; + Named_constant::import_const(this, &name, &type, &expr); + Typed_identifier tid(name, type, this->location_); + Named_object* no = this->package_->add_constant(tid, expr); + if (this->add_to_globals_) + this->gogo_->add_named_object(no); +} + +// Import a type. + +void +Import::import_type() +{ + Named_type* type; + Named_type::import_named_type(this, &type); + + // The named type has been added to the package by the type import + // process. Here we need to make it visible to the parser, and it + // to the global bindings if necessary. + type->set_is_visible(); + + if (this->add_to_globals_) + this->gogo_->add_named_type(type); +} + +// Import a variable. + +void +Import::import_var() +{ + std::string name; + Type* type; + Variable::import_var(this, &name, &type); + Variable* var = new Variable(type, NULL, true, false, false, + this->location_); + Named_object* no; + no = this->package_->add_variable(name, var); + if (this->add_to_globals_) + this->gogo_->add_named_object(no); +} + +// Import a function into PACKAGE. PACKAGE is normally +// THIS->PACKAGE_, but it will be different for a method associated +// with a type defined in a different package. + +Named_object* +Import::import_func(Package* package) +{ + std::string name; + Typed_identifier* receiver; + Typed_identifier_list* parameters; + Typed_identifier_list* results; + bool is_varargs; + Function::import_func(this, &name, &receiver, ¶meters, &results, + &is_varargs); + Function_type *fntype = Type::make_function_type(receiver, parameters, + results, this->location_); + if (is_varargs) + fntype->set_is_varargs(); + + source_location loc = this->location_; + Named_object* no; + if (fntype->is_method()) + { + Type* rtype = receiver->type()->deref(); + if (rtype->is_error_type()) + return NULL; + Named_type* named_rtype = rtype->named_type(); + gcc_assert(named_rtype != NULL); + no = named_rtype->add_method_declaration(name, package, fntype, loc); + } + else + { + no = package->add_function_declaration(name, fntype, loc); + if (this->add_to_globals_) + this->gogo_->add_named_object(no); + } + return no; +} + +// Read a type in the import stream. This records the type by the +// type index. If the type is named, it registers the name, but marks +// it as invisible. + +Type* +Import::read_type() +{ + Stream* stream = this->stream_; + this->require_c_string("<type "); + + std::string number; + int c; + while (true) + { + c = stream->get_char(); + if (c != '-' && (c < '0' || c > '9')) + break; + number += c; + } + + int index; + if (!this->string_to_int(number, true, &index)) + return Type::make_error_type(); + + if (c == '>') + { + // This type was already defined. + if (index < 0 + ? (static_cast<size_t>(- index) >= this->builtin_types_.size() + || this->builtin_types_[- index] == NULL) + : (static_cast<size_t>(index) >= this->types_.size() + || this->types_[index] == NULL)) + { + error_at(this->location_, + "error in import data at %d: bad type index %d", + stream->pos(), index); + stream->set_saw_error(); + return Type::make_error_type(); + } + + return index < 0 ? this->builtin_types_[- index] : this->types_[index]; + } + + if (c != ' ') + { + if (!stream->saw_error()) + error_at(this->location_, + "error in import data at %d: expect %< %> or %<>%>'", + stream->pos()); + stream->set_saw_error(); + stream->advance(1); + return Type::make_error_type(); + } + + if (index <= 0 + || (static_cast<size_t>(index) < this->types_.size() + && this->types_[index] != NULL)) + { + error_at(this->location_, + "error in import data at %d: type index already defined", + stream->pos()); + stream->set_saw_error(); + return Type::make_error_type(); + } + + if (static_cast<size_t>(index) >= this->types_.size()) + { + int newsize = std::max(static_cast<size_t>(index) + 1, + this->types_.size() * 2); + this->types_.resize(newsize, NULL); + } + + if (stream->peek_char() != '"') + { + Type* type = Type::import_type(this); + this->require_c_string(">"); + this->types_[index] = type; + return type; + } + + // This type has a name. + + stream->advance(1); + std::string type_name; + while ((c = stream->get_char()) != '"') + type_name += c; + + // If this type is in the current package, the name will be + // .PREFIX.PACKAGE.NAME or simply NAME with no dots. Otherwise, a + // non-hidden symbol will be PREFIX.PACKAGE.NAME and a hidden symbol + // will be .PREFIX.PACKAGE.NAME. + std::string package_name; + std::string unique_prefix; + if (type_name.find('.') != std::string::npos) + { + bool is_hidden = false; + size_t start = 0; + if (type_name[0] == '.') + { + ++start; + is_hidden = true; + } + size_t dot1 = type_name.find('.', start); + size_t dot2; + if (dot1 == std::string::npos) + dot2 = std::string::npos; + else + dot2 = type_name.find('.', dot1 + 1); + if (dot1 == std::string::npos || dot2 == std::string::npos) + { + error_at(this->location_, + ("error at import data at %d: missing dot in type name"), + stream->pos()); + stream->set_saw_error(); + } + else + { + unique_prefix = type_name.substr(start, dot1 - start); + package_name = type_name.substr(dot1 + 1, dot2 - (dot1 + 1)); + } + if (!is_hidden) + type_name.erase(0, dot2 + 1); + } + + this->require_c_string(" "); + + // Declare the type in the appropriate package. If we haven't seen + // it before, mark it as invisible. We declare it before we read + // the actual definition of the type, since the definition may refer + // to the type itself. + Package* package; + if (package_name.empty()) + package = this->package_; + else + package = this->gogo_->register_package(package_name, unique_prefix, + UNKNOWN_LOCATION); + + Named_object* no = package->bindings()->lookup(type_name); + if (no == NULL) + no = package->add_type_declaration(type_name, this->location_); + else if (!no->is_type_declaration() && !no->is_type()) + { + error_at(this->location_, "imported %<%s.%s%> both type and non-type", + Gogo::message_name(package->name()).c_str(), + Gogo::message_name(type_name).c_str()); + stream->set_saw_error(); + return Type::make_error_type(); + } + else + gcc_assert(no->package() == package); + + if (this->types_[index] == NULL) + { + if (no->is_type_declaration()) + { + // FIXME: It's silly to make a forward declaration every time. + this->types_[index] = Type::make_forward_declaration(no); + } + else + { + gcc_assert(no->is_type()); + this->types_[index] = no->type_value(); + } + } + + // If there is no type definition, then this is just a forward + // declaration of a type defined in some other file. + Type* type; + if (this->match_c_string(">")) + type = this->types_[index]; + else + { + type = this->read_type(); + + if (no->is_type_declaration()) + { + // We can define the type now. + + no = package->add_type(type_name, type, this->location_); + Named_type* ntype = no->type_value(); + + // This type has not yet been imported. + ntype->clear_is_visible(); + + type = ntype; + } + else if (no->is_type()) + { + // We have seen this type before. FIXME: it would be a good + // idea to check that the two imported types are identical, + // but we have not finalized the methds yet, which means + // that we can nt reliably compare interface types. + type = no->type_value(); + + // Don't change the visibility of the existing type. + } + + this->types_[index] = type; + + // Read the type methods. + if (this->match_c_string("\n")) + { + this->advance(1); + while (this->match_c_string(" func")) + { + this->advance(1); + this->import_func(package); + } + } + } + + this->require_c_string(">"); + + return type; +} + +// Register the builtin types. + +void +Import::register_builtin_types(Gogo* gogo) +{ + this->register_builtin_type(gogo, "int8", BUILTIN_INT8); + this->register_builtin_type(gogo, "int16", BUILTIN_INT16); + this->register_builtin_type(gogo, "int32", BUILTIN_INT32); + this->register_builtin_type(gogo, "int64", BUILTIN_INT64); + this->register_builtin_type(gogo, "uint8", BUILTIN_UINT8); + this->register_builtin_type(gogo, "uint16", BUILTIN_UINT16); + this->register_builtin_type(gogo, "uint32", BUILTIN_UINT32); + this->register_builtin_type(gogo, "uint64", BUILTIN_UINT64); + this->register_builtin_type(gogo, "float32", BUILTIN_FLOAT32); + this->register_builtin_type(gogo, "float64", BUILTIN_FLOAT64); + this->register_builtin_type(gogo, "complex64", BUILTIN_COMPLEX64); + this->register_builtin_type(gogo, "complex128", BUILTIN_COMPLEX128); + this->register_builtin_type(gogo, "int", BUILTIN_INT); + this->register_builtin_type(gogo, "uint", BUILTIN_UINT); + this->register_builtin_type(gogo, "uintptr", BUILTIN_UINTPTR); + this->register_builtin_type(gogo, "bool", BUILTIN_BOOL); + this->register_builtin_type(gogo, "string", BUILTIN_STRING); +} + +// Register a single builtin type. + +void +Import::register_builtin_type(Gogo* gogo, const char* name, Builtin_code code) +{ + Named_object* named_object = gogo->lookup_global(name); + gcc_assert(named_object != NULL && named_object->is_type()); + int index = - static_cast<int>(code); + gcc_assert(index > 0 + && static_cast<size_t>(index) < this->builtin_types_.size()); + this->builtin_types_[index] = named_object->type_value(); +} + +// Read an identifier from the stream. + +std::string +Import::read_identifier() +{ + std::string ret; + Stream* stream = this->stream_; + int c; + while (true) + { + c = stream->peek_char(); + if (c == -1 || c == ' ' || c == ';') + break; + ret += c; + stream->advance(1); + } + return ret; +} + +// Turn a string into a integer with appropriate error handling. + +bool +Import::string_to_int(const std::string &s, bool is_neg_ok, int* ret) +{ + char* end; + long prio = strtol(s.c_str(), &end, 10); + if (*end != '\0' || prio > 0x7fffffff || (prio < 0 && !is_neg_ok)) + { + error_at(this->location_, "invalid integer in import data at %d", + this->stream_->pos()); + this->stream_->set_saw_error(); + return false; + } + *ret = prio; + return true; +} + +// Class Import::Stream. + +Import::Stream::Stream() + : pos_(0), saw_error_(false) +{ +} + +Import::Stream::~Stream() +{ +} + +// Return the next character to come from the stream. + +int +Import::Stream::peek_char() +{ + const char* read; + if (!this->do_peek(1, &read)) + return -1; + // Make sure we return an unsigned char, so that we don't get + // confused by \xff. + unsigned char ret = *read; + return ret; +} + +// Return true if the next LENGTH characters from the stream match +// BYTES + +bool +Import::Stream::match_bytes(const char* bytes, size_t length) +{ + const char* read; + if (!this->do_peek(length, &read)) + return false; + return memcmp(bytes, read, length) == 0; +} + +// Require that the next LENGTH bytes from the stream match BYTES. + +void +Import::Stream::require_bytes(source_location location, const char* bytes, + size_t length) +{ + const char* read; + if (!this->do_peek(length, &read) + || memcmp(bytes, read, length) != 0) + { + if (!this->saw_error_) + error_at(location, "import error at %d: expected %<%.*s%>", + this->pos(), static_cast<int>(length), bytes); + this->saw_error_ = true; + return; + } + this->advance(length); +} + +// Class Stream_from_file. + +Stream_from_file::Stream_from_file(int fd) + : fd_(fd), data_() +{ + if (lseek(fd, 0, SEEK_SET) != 0) + { + error("lseek failed: %m"); + this->set_saw_error(); + } +} + +Stream_from_file::~Stream_from_file() +{ + close(this->fd_); +} + +// Read next bytes. + +bool +Stream_from_file::do_peek(size_t length, const char** bytes) +{ + if (this->data_.length() <= length) + { + *bytes = this->data_.data(); + return true; + } + // Don't bother to handle the general case, since we don't need it. + gcc_assert(length < 64); + char buf[64]; + ssize_t got = read(this->fd_, buf, length); + + if (got < 0) + { + if (!this->saw_error()) + error("read failed: %m"); + this->set_saw_error(); + return false; + } + + if (lseek(this->fd_, - got, SEEK_CUR) != 0) + { + if (!this->saw_error()) + error("lseek failed: %m"); + this->set_saw_error(); + return false; + } + + if (static_cast<size_t>(got) < length) + return false; + + this->data_.assign(buf, got); + + *bytes = this->data_.data(); + return true; +} + +// Advance. + +void +Stream_from_file::do_advance(size_t skip) +{ + if (lseek(this->fd_, skip, SEEK_CUR) != 0) + { + if (!this->saw_error()) + error("lseek failed: %m"); + this->set_saw_error(); + } + if (!this->data_.empty()) + { + if (this->data_.length() < skip) + this->data_.erase(0, skip); + else + this->data_.clear(); + } +} diff --git a/gcc/go/gofrontend/import.h b/gcc/go/gofrontend/import.h new file mode 100644 index 000000000..0101a40c9 --- /dev/null +++ b/gcc/go/gofrontend/import.h @@ -0,0 +1,351 @@ +// import.h -- Go frontend import declarations. -*- C++ -*- + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef GO_IMPORT_H +#define GO_IMPORT_H + +#include "export.h" + +class Gogo; +class Package; +class Type; +class Named_object; +class Named_type; +class Expression; + +// This class manages importing Go declarations. + +class Import +{ + public: + // The Stream class is an interface used to read the data. The + // caller should instantiate a child of this class. + class Stream + { + public: + Stream(); + virtual ~Stream(); + + // Return whether we have seen an error. + bool + saw_error() const + { return this->saw_error_; } + + // Record that we've seen an error. + void + set_saw_error() + { this->saw_error_ = true; } + + // Return the next character (a value from 0 to 0xff) without + // advancing. Returns -1 at end of stream. + int + peek_char(); + + // Look for LENGTH characters, setting *BYTES to point to them. + // Returns false if the bytes are not available. Does not + // advance. + bool + peek(size_t length, const char** bytes) + { return this->do_peek(length, bytes); } + + // Return the next character (a value from 0 to 0xff) and advance + // the read position by 1. Returns -1 at end of stream. + int + get_char() + { + int c = this->peek_char(); + this->advance(1); + return c; + } + + // Return true if at the end of the stream. + bool + at_eof() + { return this->peek_char() == -1; } + + // Return true if the next bytes match STR. + bool + match_c_string(const char* str) + { return this->match_bytes(str, strlen(str)); } + + // Return true if the next LENGTH bytes match BYTES. + bool + match_bytes(const char* bytes, size_t length); + + // Give an error if the next bytes do not match STR. Advance the + // read position by the length of STR. + void + require_c_string(source_location location, const char* str) + { this->require_bytes(location, str, strlen(str)); } + + // Given an error if the next LENGTH bytes do not match BYTES. + // Advance the read position by LENGTH. + void + require_bytes(source_location, const char* bytes, size_t length); + + // Advance the read position by SKIP bytes. + void + advance(size_t skip) + { + this->do_advance(skip); + this->pos_ += skip; + } + + // Return the current read position. This returns int because it + // is more convenient in error reporting. FIXME. + int + pos() + { return static_cast<int>(this->pos_); } + + protected: + // This function should set *BYTES to point to a buffer holding + // the LENGTH bytes at the current read position. It should + // return false if the bytes are not available. This should not + // change the current read position. + virtual bool + do_peek(size_t length, const char** bytes) = 0; + + // This function should advance the current read position LENGTH + // bytes. + virtual void + do_advance(size_t skip) = 0; + + private: + // The current read position. + size_t pos_; + // True if we've seen an error reading from this stream. + bool saw_error_; + }; + + // Find import data. This searches the file system for FILENAME and + // returns a pointer to a Stream object to read the data that it + // exports. LOCATION is the location of the import statement. + static Stream* + open_package(const std::string& filename, source_location location); + + // Constructor. + Import(Stream*, source_location); + + // Register the builtin types. + void + register_builtin_types(Gogo*); + + // Import everything defined in the stream. LOCAL_NAME is the local + // name to be used for bindings; if it is the string "." then + // bindings should be inserted in the global scope. If LOCAL_NAME + // is the empty string then the name of the package itself is the + // local name. This returns the imported package, or NULL on error. + Package* + import(Gogo*, const std::string& local_name, bool is_local_name_exported); + + // The location of the import statement. + source_location + location() const + { return this->location_; } + + // Return the next character. + int + peek_char() + { return this->stream_->peek_char(); } + + // Return the next character and advance. + int + get_char() + { return this->stream_->get_char(); } + + // Return true at the end of the stream. + bool + at_eof() + { return this->stream_->at_eof(); } + + // Return whether the next bytes match STR. + bool + match_c_string(const char* str) + { return this->stream_->match_c_string(str); } + + // Require that the next bytes match STR. + void + require_c_string(const char* str) + { this->stream_->require_c_string(this->location_, str); } + + // Advance the stream SKIP bytes. + void + advance(size_t skip) + { this->stream_->advance(skip); } + + // Read an identifier. + std::string + read_identifier(); + + // Read a type. + Type* + read_type(); + + // The name used for parameters, receivers, and results in imported + // function types. + static const char* const import_marker; + + private: + static Stream* + try_package_in_directory(const std::string&, source_location); + + static int + try_suffixes(std::string*); + + static Stream* + find_export_data(const std::string& filename, int fd, source_location); + + static Stream* + find_object_export_data(const std::string& filename, int fd, + off_t offset, source_location); + + static const int archive_magic_len = 8; + + static bool + is_archive_magic(const char*); + + static Stream* + find_archive_export_data(const std::string& filename, int fd, + source_location); + + // Read the import control functions. + void + read_import_init_fns(Gogo*); + + // Import a constant. + void + import_const(); + + // Import a type. + void + import_type(); + + // Import a variable. + void + import_var(); + + // Import a function. + Named_object* + import_func(Package*); + + // Register a single builtin type. + void + register_builtin_type(Gogo*, const char* name, Builtin_code); + + // Get an integer from a string. + bool + string_to_int(const std::string&, bool is_neg_ok, int* ret); + + // The general IR. + Gogo* gogo_; + // The stream from which to read import data. + Stream* stream_; + // The location of the import statement we are processing. + source_location location_; + // The package we are importing. + Package* package_; + // Whether to add new objects to the global scope, rather than to a + // package scope. + bool add_to_globals_; + // Mapping from negated builtin type codes to Type structures. + std::vector<Named_type*> builtin_types_; + // Mapping from exported type codes to Type structures. + std::vector<Type*> types_; +}; + +// Read import data from a string. + +class Stream_from_string : public Import::Stream +{ + public: + Stream_from_string(const std::string& str) + : str_(str), pos_(0) + { } + + protected: + bool + do_peek(size_t length, const char** bytes) + { + if (this->pos_ + length > this->str_.length()) + return false; + *bytes = this->str_.data() + this->pos_; + return true; + } + + void + do_advance(size_t len) + { this->pos_ += len; } + + private: + // The string of data we are reading. + std::string str_; + // The current position within the string. + size_t pos_; +}; + +// Read import data from an allocated buffer. + +class Stream_from_buffer : public Import::Stream +{ + public: + Stream_from_buffer(char* buf, size_t length) + : buf_(buf), length_(length), pos_(0) + { } + + ~Stream_from_buffer() + { delete[] this->buf_; } + + protected: + bool + do_peek(size_t length, const char** bytes) + { + if (this->pos_ + length > this->length_) + return false; + *bytes = this->buf_ + this->pos_; + return true; + } + + void + do_advance(size_t len) + { this->pos_ += len; } + + private: + // The data we are reading. + char* buf_; + // The length of the buffer. + size_t length_; + // The current position within the buffer. + size_t pos_; +}; + +// Read import data from an open file descriptor. + +class Stream_from_file : public Import::Stream +{ + public: + Stream_from_file(int fd); + + ~Stream_from_file(); + + protected: + bool + do_peek(size_t, const char**); + + void + do_advance(size_t); + + private: + // No copying. + Stream_from_file(const Stream_from_file&); + Stream_from_file& operator=(const Stream_from_file&); + + // The file descriptor. + int fd_; + // Data read from the file. + std::string data_; +}; + +#endif // !defined(GO_IMPORT_H) diff --git a/gcc/go/gofrontend/lex.cc b/gcc/go/gofrontend/lex.cc new file mode 100644 index 000000000..90b41ea2e --- /dev/null +++ b/gcc/go/gofrontend/lex.cc @@ -0,0 +1,2313 @@ +// lex.cc -- Go frontend lexer. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include "lex.h" + +// Manage mapping from keywords to the Keyword codes. + +class Keywords +{ + public: + // The structure which maps keywords to codes. + struct Mapping + { + // Keyword string. + const char* keystring; + // Keyword code. + Keyword keycode; + }; + + // Return the parsecode corresponding to KEYSTRING, or + // KEYWORD_INVALID if it is not a keyword. + Keyword + keyword_to_code(const char* keyword, size_t len) const; + + // Return the string for a keyword. + const char* + keyword_to_string(Keyword) const; + + private: + static const Mapping mapping_[]; + static const int count_; +}; + +// Mapping from keyword string to keyword code. This array must be +// kept in sorted order, and the order must match the Keyword enum. +// Strings are looked up using bsearch. + +const Keywords::Mapping +Keywords::mapping_[] = +{ + { NULL, KEYWORD_INVALID }, + { "__asm__", KEYWORD_ASM }, + { "break", KEYWORD_BREAK }, + { "case", KEYWORD_CASE }, + { "chan", KEYWORD_CHAN }, + { "const", KEYWORD_CONST }, + { "continue", KEYWORD_CONTINUE }, + { "default", KEYWORD_DEFAULT }, + { "defer", KEYWORD_DEFER }, + { "else", KEYWORD_ELSE }, + { "fallthrough", KEYWORD_FALLTHROUGH }, + { "for", KEYWORD_FOR }, + { "func", KEYWORD_FUNC }, + { "go", KEYWORD_GO }, + { "goto", KEYWORD_GOTO }, + { "if", KEYWORD_IF }, + { "import", KEYWORD_IMPORT }, + { "interface", KEYWORD_INTERFACE }, + { "map", KEYWORD_MAP }, + { "package", KEYWORD_PACKAGE }, + { "range", KEYWORD_RANGE }, + { "return", KEYWORD_RETURN }, + { "select", KEYWORD_SELECT }, + { "struct", KEYWORD_STRUCT }, + { "switch", KEYWORD_SWITCH }, + { "type", KEYWORD_TYPE }, + { "var", KEYWORD_VAR } +}; + +// Number of entries in the map. + +const int Keywords::count_ = + sizeof(Keywords::mapping_) / sizeof(Keywords::mapping_[0]); + +// Comparison function passed to bsearch. + +extern "C" +{ + +struct Keywords_search_key +{ + const char* str; + size_t len; +}; + +static int +keyword_compare(const void* keyv, const void* mapv) +{ + const Keywords_search_key* key = + static_cast<const Keywords_search_key*>(keyv); + const Keywords::Mapping* map = + static_cast<const Keywords::Mapping*>(mapv); + if (map->keystring == NULL) + return 1; + int i = strncmp(key->str, map->keystring, key->len); + if (i != 0) + return i; + if (map->keystring[key->len] != '\0') + return -1; + return 0; +} + +} // End extern "C". + +// Convert a string to a keyword code. Return KEYWORD_INVALID if the +// string is not a keyword. + +Keyword +Keywords::keyword_to_code(const char* keyword, size_t len) const +{ + Keywords_search_key key; + key.str = keyword; + key.len = len; + void* mapv = bsearch(&key, + this->mapping_, + this->count_, + sizeof(this->mapping_[0]), + keyword_compare); + if (mapv == NULL) + return KEYWORD_INVALID; + Mapping* map = static_cast<Mapping*>(mapv); + return map->keycode; +} + +// Convert a keyword code to a string. + +const char* +Keywords::keyword_to_string(Keyword code) const +{ + gcc_assert(code > KEYWORD_INVALID && code < this->count_); + const Mapping* map = &this->mapping_[code]; + gcc_assert(map->keycode == code); + return map->keystring; +} + +// There is one instance of the Keywords class. + +static Keywords keywords; + +// Class Token. + +// Make a general token. + +Token::Token(Classification classification, source_location location) + : classification_(classification), location_(location) +{ +} + +// Destroy a token. + +Token::~Token() +{ + this->clear(); +} + +// Clear a token--release memory. + +void +Token::clear() +{ + if (this->classification_ == TOKEN_INTEGER) + mpz_clear(this->u_.integer_value); + else if (this->classification_ == TOKEN_FLOAT + || this->classification_ == TOKEN_IMAGINARY) + mpfr_clear(this->u_.float_value); +} + +// Construct a token. + +Token::Token(const Token& tok) + : classification_(tok.classification_), location_(tok.location_) +{ + switch (this->classification_) + { + case TOKEN_INVALID: + case TOKEN_EOF: + break; + case TOKEN_KEYWORD: + this->u_.keyword = tok.u_.keyword; + break; + case TOKEN_IDENTIFIER: + case TOKEN_STRING: + this->u_.string_value = tok.u_.string_value; + break; + case TOKEN_OPERATOR: + this->u_.op = tok.u_.op; + break; + case TOKEN_INTEGER: + mpz_init_set(this->u_.integer_value, tok.u_.integer_value); + break; + case TOKEN_FLOAT: + case TOKEN_IMAGINARY: + mpfr_init_set(this->u_.float_value, tok.u_.float_value, GMP_RNDN); + break; + default: + gcc_unreachable(); + } +} + +// Assign to a token. + +Token& +Token::operator=(const Token& tok) +{ + this->clear(); + this->classification_ = tok.classification_; + this->location_ = tok.location_; + switch (tok.classification_) + { + case TOKEN_INVALID: + case TOKEN_EOF: + break; + case TOKEN_KEYWORD: + this->u_.keyword = tok.u_.keyword; + break; + case TOKEN_IDENTIFIER: + this->u_.identifier_value.name = tok.u_.identifier_value.name; + this->u_.identifier_value.is_exported = + tok.u_.identifier_value.is_exported; + break; + case TOKEN_STRING: + this->u_.string_value = tok.u_.string_value; + break; + case TOKEN_OPERATOR: + this->u_.op = tok.u_.op; + break; + case TOKEN_INTEGER: + mpz_init_set(this->u_.integer_value, tok.u_.integer_value); + break; + case TOKEN_FLOAT: + case TOKEN_IMAGINARY: + mpfr_init_set(this->u_.float_value, tok.u_.float_value, GMP_RNDN); + break; + default: + gcc_unreachable(); + } + return *this; +} + +// Print the token for debugging. + +void +Token::print(FILE* file) const +{ + switch (this->classification_) + { + case TOKEN_INVALID: + fprintf(file, "invalid"); + break; + case TOKEN_EOF: + fprintf(file, "EOF"); + break; + case TOKEN_KEYWORD: + fprintf(file, "keyword %s", keywords.keyword_to_string(this->u_.keyword)); + break; + case TOKEN_IDENTIFIER: + fprintf(file, "identifier \"%s\"", this->u_.string_value->c_str()); + break; + case TOKEN_STRING: + fprintf(file, "quoted string \"%s\"", this->u_.string_value->c_str()); + break; + case TOKEN_INTEGER: + fprintf(file, "integer "); + mpz_out_str(file, 10, this->u_.integer_value); + break; + case TOKEN_FLOAT: + fprintf(file, "float "); + mpfr_out_str(file, 10, 0, this->u_.float_value, GMP_RNDN); + break; + case TOKEN_IMAGINARY: + fprintf(file, "imaginary "); + mpfr_out_str(file, 10, 0, this->u_.float_value, GMP_RNDN); + break; + case TOKEN_OPERATOR: + fprintf(file, "operator "); + switch (this->u_.op) + { + case OPERATOR_INVALID: + fprintf(file, "invalid"); + break; + case OPERATOR_OROR: + fprintf(file, "||"); + break; + case OPERATOR_ANDAND: + fprintf(file, "&&"); + break; + case OPERATOR_EQEQ: + fprintf(file, "=="); + break; + case OPERATOR_NOTEQ: + fprintf(file, "!="); + break; + case OPERATOR_LT: + fprintf(file, "<"); + break; + case OPERATOR_LE: + fprintf(file, "<="); + break; + case OPERATOR_GT: + fprintf(file, ">"); + break; + case OPERATOR_GE: + fprintf(file, ">="); + break; + case OPERATOR_PLUS: + fprintf(file, "+"); + break; + case OPERATOR_MINUS: + fprintf(file, "-"); + break; + case OPERATOR_OR: + fprintf(file, "|"); + break; + case OPERATOR_XOR: + fprintf(file, "^"); + break; + case OPERATOR_MULT: + fprintf(file, "*"); + break; + case OPERATOR_DIV: + fprintf(file, "/"); + break; + case OPERATOR_MOD: + fprintf(file, "%%"); + break; + case OPERATOR_LSHIFT: + fprintf(file, "<<"); + break; + case OPERATOR_RSHIFT: + fprintf(file, ">>"); + break; + case OPERATOR_AND: + fprintf(file, "&"); + break; + case OPERATOR_BITCLEAR: + fprintf(file, "&^"); + break; + case OPERATOR_NOT: + fprintf(file, "!"); + break; + case OPERATOR_CHANOP: + fprintf(file, "<-"); + break; + case OPERATOR_EQ: + fprintf(file, "="); + break; + case OPERATOR_PLUSEQ: + fprintf(file, "+="); + break; + case OPERATOR_MINUSEQ: + fprintf(file, "-="); + break; + case OPERATOR_OREQ: + fprintf(file, "|="); + break; + case OPERATOR_XOREQ: + fprintf(file, "^="); + break; + case OPERATOR_MULTEQ: + fprintf(file, "*="); + break; + case OPERATOR_DIVEQ: + fprintf(file, "/="); + break; + case OPERATOR_MODEQ: + fprintf(file, "%%="); + break; + case OPERATOR_LSHIFTEQ: + fprintf(file, "<<="); + break; + case OPERATOR_RSHIFTEQ: + fprintf(file, ">>="); + break; + case OPERATOR_ANDEQ: + fprintf(file, "&="); + break; + case OPERATOR_BITCLEAREQ: + fprintf(file, "&^="); + break; + case OPERATOR_PLUSPLUS: + fprintf(file, "++"); + break; + case OPERATOR_MINUSMINUS: + fprintf(file, "--"); + break; + case OPERATOR_COLON: + fprintf(file, ":"); + break; + case OPERATOR_COLONEQ: + fprintf(file, ":="); + break; + case OPERATOR_SEMICOLON: + fprintf(file, ";"); + break; + case OPERATOR_DOT: + fprintf(file, "."); + break; + case OPERATOR_COMMA: + fprintf(file, ","); + break; + case OPERATOR_LPAREN: + fprintf(file, "("); + break; + case OPERATOR_RPAREN: + fprintf(file, ")"); + break; + case OPERATOR_LCURLY: + fprintf(file, "{"); + break; + case OPERATOR_RCURLY: + fprintf(file, "}"); + break; + case OPERATOR_LSQUARE: + fprintf(file, "["); + break; + case OPERATOR_RSQUARE: + fprintf(file, "]"); + break; + default: + gcc_unreachable(); + } + break; + default: + gcc_unreachable(); + } +} + +// Class Lex. + +Lex::Lex(const char* input_file_name, FILE* input_file) + : input_file_name_(input_file_name), input_file_(input_file), + linebuf_(NULL), linebufsize_(120), linesize_(0), lineoff_(0), + lineno_(0), add_semi_at_eol_(false) +{ + this->linebuf_ = new char[this->linebufsize_]; + linemap_add(line_table, LC_ENTER, 0, input_file_name, 1); +} + +Lex::~Lex() +{ + delete[] this->linebuf_; + linemap_add(line_table, LC_LEAVE, 0, NULL, 0); +} + +// Read a new line from the file. + +ssize_t +Lex::get_line() +{ + char* buf = this->linebuf_; + size_t size = this->linebufsize_; + + FILE* file = this->input_file_; + size_t cur = 0; + while (true) + { + int c = getc(file); + if (c == EOF) + { + if (cur == 0) + return -1; + break; + } + if (cur + 1 >= size) + { + size_t ns = 2 * size + 1; + if (ns < size || static_cast<ssize_t>(ns) < 0) + error_at(this->location(), "out of memory"); + char* nb = new char[ns]; + memcpy(nb, buf, cur); + delete[] buf; + buf = nb; + size = ns; + } + buf[cur] = c; + ++cur; + + if (c == '\n') + break; + } + + buf[cur] = '\0'; + + this->linebuf_ = buf; + this->linebufsize_ = size; + + return cur; +} + +// See if we need to read a new line. Return true if there is a new +// line, false if we are at EOF. + +bool +Lex::require_line() +{ + if (this->lineoff_ < this->linesize_) + return true; + + ssize_t got = this->get_line(); + if (got < 0) + return false; + ++this->lineno_; + this->linesize_= got; + this->lineoff_ = 0; + + linemap_line_start(line_table, this->lineno_, this->linesize_); + + return true; +} + +// Get the current location. + +source_location +Lex::location() const +{ + source_location location; + LINEMAP_POSITION_FOR_COLUMN(location, line_table, this->lineoff_ + 1); + return location; +} + +// Get a location slightly before the current one. This is used for +// slightly more efficient handling of operator tokens. + +source_location +Lex::earlier_location(int chars) const +{ + source_location location; + LINEMAP_POSITION_FOR_COLUMN(location, line_table, this->lineoff_ + 1 - chars); + return location; +} + +// Get the next token. + +Token +Lex::next_token() +{ + while (true) + { + if (!this->require_line()) + { + bool add_semi_at_eol = this->add_semi_at_eol_; + this->add_semi_at_eol_ = false; + if (add_semi_at_eol) + return this->make_operator(OPERATOR_SEMICOLON, 1); + return this->make_eof_token(); + } + + const char* p = this->linebuf_ + this->lineoff_; + const char* pend = this->linebuf_ + this->linesize_; + + while (p < pend) + { + unsigned char cc = *p; + switch (cc) + { + case ' ': case '\t': case '\r': + ++p; + // Skip whitespace quickly. + while (*p == ' ' || *p == '\t' || *p == '\r') + ++p; + break; + + case '\n': + { + ++p; + bool add_semi_at_eol = this->add_semi_at_eol_; + this->add_semi_at_eol_ = false; + if (add_semi_at_eol) + { + this->lineoff_ = p - this->linebuf_; + return this->make_operator(OPERATOR_SEMICOLON, 1); + } + } + break; + + case '/': + if (p[1] == '/') + { + this->lineoff_ = p + 2 - this->linebuf_; + this->skip_cpp_comment(); + p = pend; + if (p[-1] == '\n' && this->add_semi_at_eol_) + --p; + } + else if (p[1] == '*') + { + this->lineoff_ = p - this->linebuf_; + source_location location = this->location(); + if (!this->skip_c_comment()) + return Token::make_invalid_token(location); + p = this->linebuf_ + this->lineoff_; + pend = this->linebuf_ + this->linesize_; + } + else if (p[1] == '=') + { + this->add_semi_at_eol_ = false; + this->lineoff_ = p + 2 - this->linebuf_; + return this->make_operator(OPERATOR_DIVEQ, 2); + } + else + { + this->add_semi_at_eol_ = false; + this->lineoff_ = p + 1 - this->linebuf_; + return this->make_operator(OPERATOR_DIV, 1); + } + break; + + case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': + case 'G': case 'H': case 'I': case 'J': case 'K': case 'L': + case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R': + case 'S': case 'T': case 'U': case 'V': case 'W': case 'X': + case 'Y': case 'Z': + case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': + case 'g': case 'h': case 'i': case 'j': case 'k': case 'l': + case 'm': case 'n': case 'o': case 'p': case 'q': case 'r': + case 's': case 't': case 'u': case 'v': case 'w': case 'x': + case 'y': case 'z': + case '_': + this->lineoff_ = p - this->linebuf_; + return this->gather_identifier(); + + case '0': case '1': case '2': case '3': case '4': + case '5': case '6': case '7': case '8': case '9': + this->add_semi_at_eol_ = true; + this->lineoff_ = p - this->linebuf_; + return this->gather_number(); + + case '\'': + this->add_semi_at_eol_ = true; + this->lineoff_ = p - this->linebuf_; + return this->gather_character(); + + case '"': + this->add_semi_at_eol_ = true; + this->lineoff_ = p - this->linebuf_; + return this->gather_string(); + + case '`': + this->add_semi_at_eol_ = true; + this->lineoff_ = p - this->linebuf_; + return this->gather_raw_string(); + + case '<': + case '>': + case '&': + if (p + 2 < pend) + { + this->add_semi_at_eol_ = false; + Operator op = this->three_character_operator(cc, p[1], p[2]); + if (op != OPERATOR_INVALID) + { + this->lineoff_ = p + 3 - this->linebuf_; + return this->make_operator(op, 3); + } + } + // Fall through. + case '|': + case '=': + case '!': + case '+': + case '-': + case '^': + case '*': + // '/' handled above. + case '%': + case ':': + case ';': + case ',': + case '(': case ')': + case '{': case '}': + case '[': case ']': + { + this->add_semi_at_eol_ = false; + Operator op = this->two_character_operator(cc, p[1]); + int chars; + if (op != OPERATOR_INVALID) + { + ++p; + chars = 2; + } + else + { + op = this->one_character_operator(cc); + chars = 1; + } + this->lineoff_ = p + 1 - this->linebuf_; + return this->make_operator(op, chars); + } + + case '.': + if (p[1] >= '0' && p[1] <= '9') + { + this->add_semi_at_eol_ = true; + this->lineoff_ = p - this->linebuf_; + return this->gather_number(); + } + if (p[1] == '.' && p[2] == '.') + { + this->add_semi_at_eol_ = false; + this->lineoff_ = p + 3 - this->linebuf_; + return this->make_operator(OPERATOR_ELLIPSIS, 3); + } + this->add_semi_at_eol_ = false; + this->lineoff_ = p + 1 - this->linebuf_; + return this->make_operator(OPERATOR_DOT, 1); + + default: + { + unsigned int ci; + bool issued_error; + this->lineoff_ = p - this->linebuf_; + this->advance_one_utf8_char(p, &ci, &issued_error); + if (Lex::is_unicode_letter(ci)) + return this->gather_identifier(); + + if (!issued_error) + error_at(this->location(), + "invalid character 0x%x in input file", + ci); + + p = pend; + + break; + } + } + } + + this->lineoff_ = p - this->linebuf_; + } +} + +// Fetch one UTF-8 character from a string. Set *VALUE to the value. +// Return the number of bytes read from the string. Returns 0 if the +// string does not point to a valid UTF-8 character. + +int +Lex::fetch_char(const char* p, unsigned int* value) +{ + unsigned char c = *p; + if (c <= 0x7f) + { + *value = c; + return 1; + } + else if ((c & 0xe0) == 0xc0 + && (p[1] & 0xc0) == 0x80) + { + *value = (((c & 0x1f) << 6) + + (p[1] & 0x3f)); + if (*value <= 0x7f) + { + *value = 0xfffd; + return 0; + } + return 2; + } + else if ((c & 0xf0) == 0xe0 + && (p[1] & 0xc0) == 0x80 + && (p[2] & 0xc0) == 0x80) + { + *value = (((c & 0xf) << 12) + + ((p[1] & 0x3f) << 6) + + (p[2] & 0x3f)); + if (*value <= 0x7ff) + { + *value = 0xfffd; + return 0; + } + return 3; + } + else if ((c & 0xf8) == 0xf0 + && (p[1] & 0xc0) == 0x80 + && (p[2] & 0xc0) == 0x80 + && (p[3] & 0xc0) == 0x80) + { + *value = (((c & 0x7) << 18) + + ((p[1] & 0x3f) << 12) + + ((p[2] & 0x3f) << 6) + + (p[3] & 0x3f)); + if (*value <= 0xffff) + { + *value = 0xfffd; + return 0; + } + return 4; + } + else + { + /* Invalid encoding. Return the Unicode replacement + character. */ + *value = 0xfffd; + return 0; + } +} + +// Advance one UTF-8 character. Return the pointer beyond the +// character. Set *VALUE to the value. Set *ISSUED_ERROR if an error +// was issued. + +const char* +Lex::advance_one_utf8_char(const char* p, unsigned int* value, + bool* issued_error) +{ + *issued_error = false; + + if (*p == '\0') + { + error_at(this->location(), "invalid NUL byte"); + *issued_error = true; + *value = 0; + return p + 1; + } + + int adv = Lex::fetch_char(p, value); + if (adv == 0) + { + error_at(this->location(), "invalid UTF-8 encoding"); + *issued_error = true; + return p + 1; + } + return p + adv; +} + +// Pick up an identifier. + +Token +Lex::gather_identifier() +{ + const char* pstart = this->linebuf_ + this->lineoff_; + const char* p = pstart; + const char* pend = this->linebuf_ + this->linesize_; + bool is_first = true; + bool is_exported = false; + bool has_non_ascii_char = false; + std::string buf; + while (p < pend) + { + unsigned char cc = *p; + if (cc <= 0x7f) + { + if ((cc < 'A' || cc > 'Z') + && (cc < 'a' || cc > 'z') + && cc != '_' + && (cc < '0' || cc > '9')) + break; + ++p; + if (is_first) + { + is_exported = cc >= 'A' && cc <= 'Z'; + is_first = false; + } + if (has_non_ascii_char) + buf.push_back(cc); + } + else + { + unsigned int ci; + bool issued_error; + this->lineoff_ = p - this->linebuf_; + const char* pnext = this->advance_one_utf8_char(p, &ci, + &issued_error); + if (!Lex::is_unicode_letter(ci) && !Lex::is_unicode_digit(ci)) + { + // There is no valid place for a non-ASCII character + // other than an identifier, so we get better error + // handling behaviour if we swallow this character after + // giving an error. + if (!issued_error) + error_at(this->location(), + "invalid character 0x%x in identifier", + ci); + } + if (is_first) + { + is_exported = Lex::is_unicode_uppercase(ci); + is_first = false; + } + if (!has_non_ascii_char) + { + buf.assign(pstart, p - pstart); + has_non_ascii_char = true; + } + p = pnext; + char ubuf[50]; + // This assumes that all assemblers can handle an identifier + // with a '$' character. + snprintf(ubuf, sizeof ubuf, "$U%x$", ci); + buf.append(ubuf); + } + } + source_location location = this->location(); + this->add_semi_at_eol_ = true; + this->lineoff_ = p - this->linebuf_; + if (has_non_ascii_char) + return Token::make_identifier_token(buf, is_exported, location); + else + { + Keyword code = keywords.keyword_to_code(pstart, p - pstart); + if (code == KEYWORD_INVALID) + return Token::make_identifier_token(std::string(pstart, p - pstart), + is_exported, location); + else + { + switch (code) + { + case KEYWORD_BREAK: + case KEYWORD_CONTINUE: + case KEYWORD_FALLTHROUGH: + case KEYWORD_RETURN: + break; + default: + this->add_semi_at_eol_ = false; + break; + } + return Token::make_keyword_token(code, location); + } + } +} + +// Return whether C is a hex digit. + +bool +Lex::is_hex_digit(char c) +{ + return ((c >= '0' && c <= '9') + || (c >= 'A' && c <= 'F') + || (c >= 'a' && c <= 'f')); +} + +// Return whether an exponent could start at P. + +bool +Lex::could_be_exponent(const char* p, const char* pend) +{ + if (*p != 'e' && *p != 'E') + return false; + ++p; + if (p >= pend) + return false; + if (*p == '+' || *p == '-') + { + ++p; + if (p >= pend) + return false; + } + return *p >= '0' && *p <= '9'; +} + +// Pick up a number. + +Token +Lex::gather_number() +{ + const char* pstart = this->linebuf_ + this->lineoff_; + const char* p = pstart; + const char* pend = this->linebuf_ + this->linesize_; + + source_location location = this->location(); + + bool neg = false; + if (*p == '+') + ++p; + else if (*p == '-') + { + ++p; + neg = true; + } + + const char* pnum = p; + if (*p == '0') + { + int base; + if ((p[1] == 'x' || p[1] == 'X') + && Lex::is_hex_digit(p[2])) + { + base = 16; + p += 2; + pnum = p; + while (p < pend) + { + if (!Lex::is_hex_digit(*p)) + break; + ++p; + } + } + else + { + base = 8; + pnum = p; + while (p < pend) + { + if (*p < '0' || *p > '7') + break; + ++p; + } + } + + if (*p != '.' && *p != 'i' && !Lex::could_be_exponent(p, pend)) + { + std::string s(pnum, p - pnum); + mpz_t val; + int r = mpz_init_set_str(val, s.c_str(), base); + gcc_assert(r == 0); + + if (neg) + mpz_neg(val, val); + + this->lineoff_ = p - this->linebuf_; + Token ret = Token::make_integer_token(val, location); + mpz_clear(val); + return ret; + } + } + + while (p < pend) + { + if (*p < '0' || *p > '9') + break; + ++p; + } + + if (*p != '.' && *p != 'i' && !Lex::could_be_exponent(p, pend)) + { + std::string s(pnum, p - pnum); + mpz_t val; + int r = mpz_init_set_str(val, s.c_str(), 10); + gcc_assert(r == 0); + + if (neg) + mpz_neg(val, val); + + this->lineoff_ = p - this->linebuf_; + Token ret = Token::make_integer_token(val, location); + mpz_clear(val); + return ret; + } + + if (*p != 'i') + { + bool dot = *p == '.'; + + ++p; + + if (!dot) + { + if (*p == '+' || *p == '-') + ++p; + } + + while (p < pend) + { + if (*p < '0' || *p > '9') + break; + ++p; + } + + if (dot && Lex::could_be_exponent(p, pend)) + { + ++p; + if (*p == '+' || *p == '-') + ++p; + while (p < pend) + { + if (*p < '0' || *p > '9') + break; + ++p; + } + } + } + + std::string s(pnum, p - pnum); + mpfr_t val; + int r = mpfr_init_set_str(val, s.c_str(), 10, GMP_RNDN); + gcc_assert(r == 0); + + if (neg) + mpfr_neg(val, val, GMP_RNDN); + + bool is_imaginary = *p == 'i'; + if (is_imaginary) + ++p; + + this->lineoff_ = p - this->linebuf_; + if (is_imaginary) + { + Token ret = Token::make_imaginary_token(val, location); + mpfr_clear(val); + return ret; + } + else + { + Token ret = Token::make_float_token(val, location); + mpfr_clear(val); + return ret; + } +} + +// Advance one character, possibly escaped. Return the pointer beyond +// the character. Set *VALUE to the character. Set *IS_CHARACTER if +// this is a character (e.g., 'a' or '\u1234') rather than a byte +// value (e.g., '\001'). + +const char* +Lex::advance_one_char(const char* p, bool is_single_quote, unsigned int* value, + bool* is_character) +{ + *value = 0; + *is_character = true; + if (*p != '\\') + { + bool issued_error; + const char* ret = this->advance_one_utf8_char(p, value, &issued_error); + if (is_single_quote + && (*value == '\'' || *value == '\n') + && !issued_error) + error_at(this->location(), "invalid character literal"); + return ret; + } + else + { + ++p; + switch (*p) + { + case '0': case '1': case '2': case '3': + case '4': case '5': case '6': case '7': + *is_character = false; + if (p[1] >= '0' && p[1] <= '7' + && p[2] >= '0' && p[2] <= '7') + { + *value = ((Lex::octal_value(p[0]) << 6) + + (Lex::octal_value(p[1]) << 3) + + Lex::octal_value(p[2])); + if (*value > 255) + { + error_at(this->location(), "invalid octal constant"); + *value = 255; + } + return p + 3; + } + error_at(this->location(), "invalid octal character"); + return (p[1] >= '0' && p[1] <= '7' + ? p + 2 + : p + 1); + + case 'x': + case 'X': + *is_character = false; + if (Lex::is_hex_digit(p[1]) && Lex::is_hex_digit(p[2])) + { + *value = (hex_value(p[1]) << 4) + hex_value(p[2]); + return p + 3; + } + error_at(this->location(), "invalid hex character"); + return (Lex::is_hex_digit(p[1]) + ? p + 2 + : p + 1); + + case 'a': + *value = '\a'; + return p + 1; + case 'b': + *value = '\b'; + return p + 1; + case 'f': + *value = '\f'; + return p + 1; + case 'n': + *value = '\n'; + return p + 1; + case 'r': + *value = '\r'; + return p + 1; + case 't': + *value = '\t'; + return p + 1; + case 'v': + *value = '\v'; + return p + 1; + case '\\': + *value = '\\'; + return p + 1; + case '\'': + if (!is_single_quote) + error_at(this->location(), "invalid quoted character"); + *value = '\''; + return p + 1; + case '"': + if (is_single_quote) + error_at(this->location(), "invalid quoted character"); + *value = '"'; + return p + 1; + + case 'u': + if (Lex::is_hex_digit(p[1]) && Lex::is_hex_digit(p[2]) + && Lex::is_hex_digit(p[3]) && Lex::is_hex_digit(p[4])) + { + *value = ((hex_value(p[1]) << 12) + + (hex_value(p[2]) << 8) + + (hex_value(p[3]) << 4) + + hex_value(p[4])); + if (*value >= 0xd800 && *value < 0xe000) + { + error_at(this->location(), + "invalid unicode code point 0x%x", + *value); + // Use the replacement character. + *value = 0xfffd; + } + return p + 5; + } + error_at(this->location(), "invalid little unicode code point"); + return p + 1; + + case 'U': + if (Lex::is_hex_digit(p[1]) && Lex::is_hex_digit(p[2]) + && Lex::is_hex_digit(p[3]) && Lex::is_hex_digit(p[4]) + && Lex::is_hex_digit(p[5]) && Lex::is_hex_digit(p[6]) + && Lex::is_hex_digit(p[7]) && Lex::is_hex_digit(p[8])) + { + *value = ((hex_value(p[1]) << 28) + + (hex_value(p[2]) << 24) + + (hex_value(p[3]) << 20) + + (hex_value(p[4]) << 16) + + (hex_value(p[5]) << 12) + + (hex_value(p[6]) << 8) + + (hex_value(p[7]) << 4) + + hex_value(p[8])); + if (*value > 0x10ffff + || (*value >= 0xd800 && *value < 0xe000)) + { + error_at(this->location(), "invalid unicode code point 0x%x", + *value); + // Use the replacement character. + *value = 0xfffd; + } + return p + 9; + } + error_at(this->location(), "invalid big unicode code point"); + return p + 1; + + default: + error_at(this->location(), "invalid character after %<\\%>"); + *value = *p; + return p + 1; + } + } +} + +// Append V to STR. IS_CHARACTER is true for a character which should +// be stored in UTF-8, false for a general byte value which should be +// stored directly. + +void +Lex::append_char(unsigned int v, bool is_character, std::string* str, + source_location location) +{ + char buf[4]; + size_t len; + if (v <= 0x7f || !is_character) + { + buf[0] = v; + len = 1; + } + else if (v <= 0x7ff) + { + buf[0] = 0xc0 + (v >> 6); + buf[1] = 0x80 + (v & 0x3f); + len = 2; + } + else + { + if (v > 0x10ffff) + { + warning_at(location, 0, + "unicode code point 0x%x out of range in string", v); + // Turn it into the "replacement character". + v = 0xfffd; + } + if (v <= 0xffff) + { + buf[0] = 0xe0 + (v >> 12); + buf[1] = 0x80 + ((v >> 6) & 0x3f); + buf[2] = 0x80 + (v & 0x3f); + len = 3; + } + else + { + buf[0] = 0xf0 + (v >> 18); + buf[1] = 0x80 + ((v >> 12) & 0x3f); + buf[2] = 0x80 + ((v >> 6) & 0x3f); + buf[3] = 0x80 + (v & 0x3f); + len = 4; + } + } + str->append(buf, len); +} + +// Pick up a character literal. + +Token +Lex::gather_character() +{ + ++this->lineoff_; + const char* pstart = this->linebuf_ + this->lineoff_; + const char* p = pstart; + + unsigned int value; + bool is_character; + p = this->advance_one_char(p, true, &value, &is_character); + + if (*p != '\'') + { + error_at(this->location(), "unterminated character constant"); + this->lineoff_ = p - this->linebuf_; + return this->make_invalid_token(); + } + + mpz_t val; + mpz_init_set_ui(val, value); + + source_location location = this->location(); + this->lineoff_ = p + 1 - this->linebuf_; + Token ret = Token::make_integer_token(val, location); + mpz_clear(val); + return ret; +} + +// Pick up a quoted string. + +Token +Lex::gather_string() +{ + const char* pstart = this->linebuf_ + this->lineoff_ + 1; + const char* p = pstart; + const char* pend = this->linebuf_ + this->linesize_; + + std::string value; + while (*p != '"') + { + source_location loc = this->location(); + unsigned int c; + bool is_character; + this->lineoff_ = p - this->linebuf_; + p = this->advance_one_char(p, false, &c, &is_character); + if (p >= pend) + { + error_at(this->location(), "unterminated string"); + --p; + break; + } + Lex::append_char(c, is_character, &value, loc); + } + + source_location location = this->location(); + this->lineoff_ = p + 1 - this->linebuf_; + return Token::make_string_token(value, location); +} + +// Pick up a raw string. + +Token +Lex::gather_raw_string() +{ + const char* p = this->linebuf_ + this->lineoff_ + 1; + const char* pend = this->linebuf_ + this->linesize_; + source_location location = this->location(); + + std::string value; + while (true) + { + while (p < pend) + { + if (*p == '`') + { + this->lineoff_ = p + 1 - this->linebuf_; + return Token::make_string_token(value, location); + } + source_location loc = this->location(); + unsigned int c; + bool issued_error; + this->lineoff_ = p - this->linebuf_; + p = this->advance_one_utf8_char(p, &c, &issued_error); + Lex::append_char(c, true, &value, loc); + } + this->lineoff_ = p - this->linebuf_; + if (!this->require_line()) + { + error_at(location, "unterminated raw string"); + return Token::make_string_token(value, location); + } + p = this->linebuf_ + this->lineoff_; + pend = this->linebuf_ + this->linesize_; + } +} + +// If C1 C2 C3 are a three character operator, return the code. + +Operator +Lex::three_character_operator(char c1, char c2, char c3) +{ + if (c3 == '=') + { + if (c1 == '<' && c2 == '<') + return OPERATOR_LSHIFTEQ; + else if (c1 == '>' && c2 == '>') + return OPERATOR_RSHIFTEQ; + else if (c1 == '&' && c2 == '^') + return OPERATOR_BITCLEAREQ; + } + return OPERATOR_INVALID; +} + +// If C1 C2 are a two character operator, return the code. + +Operator +Lex::two_character_operator(char c1, char c2) +{ + switch (c1) + { + case '|': + if (c2 == '|') + return OPERATOR_OROR; + else if (c2 == '=') + return OPERATOR_OREQ; + break; + case '&': + if (c2 == '&') + return OPERATOR_ANDAND; + else if (c2 == '^') + return OPERATOR_BITCLEAR; + else if (c2 == '=') + return OPERATOR_ANDEQ; + break; + case '^': + if (c2 == '=') + return OPERATOR_XOREQ; + break; + case '=': + if (c2 == '=') + return OPERATOR_EQEQ; + break; + case '!': + if (c2 == '=') + return OPERATOR_NOTEQ; + break; + case '<': + if (c2 == '=') + return OPERATOR_LE; + else if (c2 == '<') + return OPERATOR_LSHIFT; + else if (c2 == '-') + return OPERATOR_CHANOP; + break; + case '>': + if (c2 == '=') + return OPERATOR_GE; + else if (c2 == '>') + return OPERATOR_RSHIFT; + break; + case '*': + if (c2 == '=') + return OPERATOR_MULTEQ; + break; + case '/': + if (c2 == '=') + return OPERATOR_DIVEQ; + break; + case '%': + if (c2 == '=') + return OPERATOR_MODEQ; + break; + case '+': + if (c2 == '+') + { + this->add_semi_at_eol_ = true; + return OPERATOR_PLUSPLUS; + } + else if (c2 == '=') + return OPERATOR_PLUSEQ; + break; + case '-': + if (c2 == '-') + { + this->add_semi_at_eol_ = true; + return OPERATOR_MINUSMINUS; + } + else if (c2 == '=') + return OPERATOR_MINUSEQ; + break; + case ':': + if (c2 == '=') + return OPERATOR_COLONEQ; + break; + default: + break; + } + return OPERATOR_INVALID; +} + +// If character C is an operator, return the code. + +Operator +Lex::one_character_operator(char c) +{ + switch (c) + { + case '<': + return OPERATOR_LT; + case '>': + return OPERATOR_GT; + case '+': + return OPERATOR_PLUS; + case '-': + return OPERATOR_MINUS; + case '|': + return OPERATOR_OR; + case '^': + return OPERATOR_XOR; + case '*': + return OPERATOR_MULT; + case '/': + return OPERATOR_DIV; + case '%': + return OPERATOR_MOD; + case '&': + return OPERATOR_AND; + case '!': + return OPERATOR_NOT; + case '=': + return OPERATOR_EQ; + case ':': + return OPERATOR_COLON; + case ';': + return OPERATOR_SEMICOLON; + case '.': + return OPERATOR_DOT; + case ',': + return OPERATOR_COMMA; + case '(': + return OPERATOR_LPAREN; + case ')': + this->add_semi_at_eol_ = true; + return OPERATOR_RPAREN; + case '{': + return OPERATOR_LCURLY; + case '}': + this->add_semi_at_eol_ = true; + return OPERATOR_RCURLY; + case '[': + return OPERATOR_LSQUARE; + case ']': + this->add_semi_at_eol_ = true; + return OPERATOR_RSQUARE; + default: + return OPERATOR_INVALID; + } +} + +// Skip a C-style comment. + +bool +Lex::skip_c_comment() +{ + while (true) + { + if (!this->require_line()) + { + error_at(this->location(), "unterminated comment"); + return false; + } + + const char* p = this->linebuf_ + this->lineoff_; + const char* pend = this->linebuf_ + this->linesize_; + + while (p < pend) + { + if (p[0] == '*' && p + 1 < pend && p[1] == '/') + { + this->lineoff_ = p + 2 - this->linebuf_; + return true; + } + + this->lineoff_ = p - this->linebuf_; + unsigned int c; + bool issued_error; + p = this->advance_one_utf8_char(p, &c, &issued_error); + } + + this->lineoff_ = p - this->linebuf_; + } +} + +// Skip a C++-style comment. + +void +Lex::skip_cpp_comment() +{ + const char* p = this->linebuf_ + this->lineoff_; + const char* pend = this->linebuf_ + this->linesize_; + + // By convention, a C++ comment at the start of the line of the form + // //line FILE:LINENO + // is interpreted as setting the file name and line number of the + // next source line. + + if (this->lineoff_ == 2 + && pend - p > 5 + && memcmp(p, "line ", 5) == 0) + { + p += 5; + while (p < pend && *p == ' ') + ++p; + const char* pcolon = static_cast<const char*>(memchr(p, ':', pend - p)); + if (pcolon != NULL + && pcolon[1] >= '0' + && pcolon[1] <= '9') + { + char* plend; + long lineno = strtol(pcolon + 1, &plend, 10); + if (plend > pcolon + 1 + && (plend == pend + || *plend < '0' + || *plend > '9') + && lineno > 0 + && lineno < 0x7fffffff) + { + unsigned int filelen = pcolon - p; + char* file = new char[filelen + 1]; + memcpy(file, p, filelen); + file[filelen] = '\0'; + + linemap_add(line_table, LC_LEAVE, 0, NULL, 0); + linemap_add(line_table, LC_ENTER, 0, file, lineno); + this->lineno_ = lineno - 1; + + p = plend; + } + } + } + + while (p < pend) + { + this->lineoff_ = p - this->linebuf_; + unsigned int c; + bool issued_error; + p = this->advance_one_utf8_char(p, &c, &issued_error); + } +} + +// The Unicode tables use this struct. + +struct Unicode_range +{ + // The low end of the range. + unsigned int low; + // The high end of the range. + unsigned int high; + // The stride. This entries represents low, low + stride, low + 2 * + // stride, etc., up to high. + unsigned int stride; +}; + +// A table of Unicode digits--Unicode code points classified as +// "Digit". + +static const Unicode_range unicode_digits[] = +{ + { 0x0030, 0x0039, 1}, + { 0x0660, 0x0669, 1}, + { 0x06f0, 0x06f9, 1}, + { 0x07c0, 0x07c9, 1}, + { 0x0966, 0x096f, 1}, + { 0x09e6, 0x09ef, 1}, + { 0x0a66, 0x0a6f, 1}, + { 0x0ae6, 0x0aef, 1}, + { 0x0b66, 0x0b6f, 1}, + { 0x0be6, 0x0bef, 1}, + { 0x0c66, 0x0c6f, 1}, + { 0x0ce6, 0x0cef, 1}, + { 0x0d66, 0x0d6f, 1}, + { 0x0e50, 0x0e59, 1}, + { 0x0ed0, 0x0ed9, 1}, + { 0x0f20, 0x0f29, 1}, + { 0x1040, 0x1049, 1}, + { 0x17e0, 0x17e9, 1}, + { 0x1810, 0x1819, 1}, + { 0x1946, 0x194f, 1}, + { 0x19d0, 0x19d9, 1}, + { 0x1b50, 0x1b59, 1}, + { 0xff10, 0xff19, 1}, + { 0x104a0, 0x104a9, 1}, + { 0x1d7ce, 0x1d7ff, 1}, +}; + +// A table of Unicode letters--Unicode code points classified as +// "Letter". + +static const Unicode_range unicode_letters[] = +{ + { 0x0041, 0x005a, 1}, + { 0x0061, 0x007a, 1}, + { 0x00aa, 0x00b5, 11}, + { 0x00ba, 0x00ba, 1}, + { 0x00c0, 0x00d6, 1}, + { 0x00d8, 0x00f6, 1}, + { 0x00f8, 0x02c1, 1}, + { 0x02c6, 0x02d1, 1}, + { 0x02e0, 0x02e4, 1}, + { 0x02ec, 0x02ee, 2}, + { 0x0370, 0x0374, 1}, + { 0x0376, 0x0377, 1}, + { 0x037a, 0x037d, 1}, + { 0x0386, 0x0386, 1}, + { 0x0388, 0x038a, 1}, + { 0x038c, 0x038c, 1}, + { 0x038e, 0x03a1, 1}, + { 0x03a3, 0x03f5, 1}, + { 0x03f7, 0x0481, 1}, + { 0x048a, 0x0523, 1}, + { 0x0531, 0x0556, 1}, + { 0x0559, 0x0559, 1}, + { 0x0561, 0x0587, 1}, + { 0x05d0, 0x05ea, 1}, + { 0x05f0, 0x05f2, 1}, + { 0x0621, 0x064a, 1}, + { 0x066e, 0x066f, 1}, + { 0x0671, 0x06d3, 1}, + { 0x06d5, 0x06d5, 1}, + { 0x06e5, 0x06e6, 1}, + { 0x06ee, 0x06ef, 1}, + { 0x06fa, 0x06fc, 1}, + { 0x06ff, 0x0710, 17}, + { 0x0712, 0x072f, 1}, + { 0x074d, 0x07a5, 1}, + { 0x07b1, 0x07b1, 1}, + { 0x07ca, 0x07ea, 1}, + { 0x07f4, 0x07f5, 1}, + { 0x07fa, 0x07fa, 1}, + { 0x0904, 0x0939, 1}, + { 0x093d, 0x0950, 19}, + { 0x0958, 0x0961, 1}, + { 0x0971, 0x0972, 1}, + { 0x097b, 0x097f, 1}, + { 0x0985, 0x098c, 1}, + { 0x098f, 0x0990, 1}, + { 0x0993, 0x09a8, 1}, + { 0x09aa, 0x09b0, 1}, + { 0x09b2, 0x09b2, 1}, + { 0x09b6, 0x09b9, 1}, + { 0x09bd, 0x09ce, 17}, + { 0x09dc, 0x09dd, 1}, + { 0x09df, 0x09e1, 1}, + { 0x09f0, 0x09f1, 1}, + { 0x0a05, 0x0a0a, 1}, + { 0x0a0f, 0x0a10, 1}, + { 0x0a13, 0x0a28, 1}, + { 0x0a2a, 0x0a30, 1}, + { 0x0a32, 0x0a33, 1}, + { 0x0a35, 0x0a36, 1}, + { 0x0a38, 0x0a39, 1}, + { 0x0a59, 0x0a5c, 1}, + { 0x0a5e, 0x0a5e, 1}, + { 0x0a72, 0x0a74, 1}, + { 0x0a85, 0x0a8d, 1}, + { 0x0a8f, 0x0a91, 1}, + { 0x0a93, 0x0aa8, 1}, + { 0x0aaa, 0x0ab0, 1}, + { 0x0ab2, 0x0ab3, 1}, + { 0x0ab5, 0x0ab9, 1}, + { 0x0abd, 0x0ad0, 19}, + { 0x0ae0, 0x0ae1, 1}, + { 0x0b05, 0x0b0c, 1}, + { 0x0b0f, 0x0b10, 1}, + { 0x0b13, 0x0b28, 1}, + { 0x0b2a, 0x0b30, 1}, + { 0x0b32, 0x0b33, 1}, + { 0x0b35, 0x0b39, 1}, + { 0x0b3d, 0x0b3d, 1}, + { 0x0b5c, 0x0b5d, 1}, + { 0x0b5f, 0x0b61, 1}, + { 0x0b71, 0x0b83, 18}, + { 0x0b85, 0x0b8a, 1}, + { 0x0b8e, 0x0b90, 1}, + { 0x0b92, 0x0b95, 1}, + { 0x0b99, 0x0b9a, 1}, + { 0x0b9c, 0x0b9c, 1}, + { 0x0b9e, 0x0b9f, 1}, + { 0x0ba3, 0x0ba4, 1}, + { 0x0ba8, 0x0baa, 1}, + { 0x0bae, 0x0bb9, 1}, + { 0x0bd0, 0x0bd0, 1}, + { 0x0c05, 0x0c0c, 1}, + { 0x0c0e, 0x0c10, 1}, + { 0x0c12, 0x0c28, 1}, + { 0x0c2a, 0x0c33, 1}, + { 0x0c35, 0x0c39, 1}, + { 0x0c3d, 0x0c3d, 1}, + { 0x0c58, 0x0c59, 1}, + { 0x0c60, 0x0c61, 1}, + { 0x0c85, 0x0c8c, 1}, + { 0x0c8e, 0x0c90, 1}, + { 0x0c92, 0x0ca8, 1}, + { 0x0caa, 0x0cb3, 1}, + { 0x0cb5, 0x0cb9, 1}, + { 0x0cbd, 0x0cde, 33}, + { 0x0ce0, 0x0ce1, 1}, + { 0x0d05, 0x0d0c, 1}, + { 0x0d0e, 0x0d10, 1}, + { 0x0d12, 0x0d28, 1}, + { 0x0d2a, 0x0d39, 1}, + { 0x0d3d, 0x0d3d, 1}, + { 0x0d60, 0x0d61, 1}, + { 0x0d7a, 0x0d7f, 1}, + { 0x0d85, 0x0d96, 1}, + { 0x0d9a, 0x0db1, 1}, + { 0x0db3, 0x0dbb, 1}, + { 0x0dbd, 0x0dbd, 1}, + { 0x0dc0, 0x0dc6, 1}, + { 0x0e01, 0x0e30, 1}, + { 0x0e32, 0x0e33, 1}, + { 0x0e40, 0x0e46, 1}, + { 0x0e81, 0x0e82, 1}, + { 0x0e84, 0x0e84, 1}, + { 0x0e87, 0x0e88, 1}, + { 0x0e8a, 0x0e8d, 3}, + { 0x0e94, 0x0e97, 1}, + { 0x0e99, 0x0e9f, 1}, + { 0x0ea1, 0x0ea3, 1}, + { 0x0ea5, 0x0ea7, 2}, + { 0x0eaa, 0x0eab, 1}, + { 0x0ead, 0x0eb0, 1}, + { 0x0eb2, 0x0eb3, 1}, + { 0x0ebd, 0x0ebd, 1}, + { 0x0ec0, 0x0ec4, 1}, + { 0x0ec6, 0x0ec6, 1}, + { 0x0edc, 0x0edd, 1}, + { 0x0f00, 0x0f00, 1}, + { 0x0f40, 0x0f47, 1}, + { 0x0f49, 0x0f6c, 1}, + { 0x0f88, 0x0f8b, 1}, + { 0x1000, 0x102a, 1}, + { 0x103f, 0x103f, 1}, + { 0x1050, 0x1055, 1}, + { 0x105a, 0x105d, 1}, + { 0x1061, 0x1061, 1}, + { 0x1065, 0x1066, 1}, + { 0x106e, 0x1070, 1}, + { 0x1075, 0x1081, 1}, + { 0x108e, 0x108e, 1}, + { 0x10a0, 0x10c5, 1}, + { 0x10d0, 0x10fa, 1}, + { 0x10fc, 0x10fc, 1}, + { 0x1100, 0x1159, 1}, + { 0x115f, 0x11a2, 1}, + { 0x11a8, 0x11f9, 1}, + { 0x1200, 0x1248, 1}, + { 0x124a, 0x124d, 1}, + { 0x1250, 0x1256, 1}, + { 0x1258, 0x1258, 1}, + { 0x125a, 0x125d, 1}, + { 0x1260, 0x1288, 1}, + { 0x128a, 0x128d, 1}, + { 0x1290, 0x12b0, 1}, + { 0x12b2, 0x12b5, 1}, + { 0x12b8, 0x12be, 1}, + { 0x12c0, 0x12c0, 1}, + { 0x12c2, 0x12c5, 1}, + { 0x12c8, 0x12d6, 1}, + { 0x12d8, 0x1310, 1}, + { 0x1312, 0x1315, 1}, + { 0x1318, 0x135a, 1}, + { 0x1380, 0x138f, 1}, + { 0x13a0, 0x13f4, 1}, + { 0x1401, 0x166c, 1}, + { 0x166f, 0x1676, 1}, + { 0x1681, 0x169a, 1}, + { 0x16a0, 0x16ea, 1}, + { 0x1700, 0x170c, 1}, + { 0x170e, 0x1711, 1}, + { 0x1720, 0x1731, 1}, + { 0x1740, 0x1751, 1}, + { 0x1760, 0x176c, 1}, + { 0x176e, 0x1770, 1}, + { 0x1780, 0x17b3, 1}, + { 0x17d7, 0x17dc, 5}, + { 0x1820, 0x1877, 1}, + { 0x1880, 0x18a8, 1}, + { 0x18aa, 0x18aa, 1}, + { 0x1900, 0x191c, 1}, + { 0x1950, 0x196d, 1}, + { 0x1970, 0x1974, 1}, + { 0x1980, 0x19a9, 1}, + { 0x19c1, 0x19c7, 1}, + { 0x1a00, 0x1a16, 1}, + { 0x1b05, 0x1b33, 1}, + { 0x1b45, 0x1b4b, 1}, + { 0x1b83, 0x1ba0, 1}, + { 0x1bae, 0x1baf, 1}, + { 0x1c00, 0x1c23, 1}, + { 0x1c4d, 0x1c4f, 1}, + { 0x1c5a, 0x1c7d, 1}, + { 0x1d00, 0x1dbf, 1}, + { 0x1e00, 0x1f15, 1}, + { 0x1f18, 0x1f1d, 1}, + { 0x1f20, 0x1f45, 1}, + { 0x1f48, 0x1f4d, 1}, + { 0x1f50, 0x1f57, 1}, + { 0x1f59, 0x1f5d, 2}, + { 0x1f5f, 0x1f7d, 1}, + { 0x1f80, 0x1fb4, 1}, + { 0x1fb6, 0x1fbc, 1}, + { 0x1fbe, 0x1fbe, 1}, + { 0x1fc2, 0x1fc4, 1}, + { 0x1fc6, 0x1fcc, 1}, + { 0x1fd0, 0x1fd3, 1}, + { 0x1fd6, 0x1fdb, 1}, + { 0x1fe0, 0x1fec, 1}, + { 0x1ff2, 0x1ff4, 1}, + { 0x1ff6, 0x1ffc, 1}, + { 0x2071, 0x207f, 14}, + { 0x2090, 0x2094, 1}, + { 0x2102, 0x2107, 5}, + { 0x210a, 0x2113, 1}, + { 0x2115, 0x2115, 1}, + { 0x2119, 0x211d, 1}, + { 0x2124, 0x2128, 2}, + { 0x212a, 0x212d, 1}, + { 0x212f, 0x2139, 1}, + { 0x213c, 0x213f, 1}, + { 0x2145, 0x2149, 1}, + { 0x214e, 0x214e, 1}, + { 0x2183, 0x2184, 1}, + { 0x2c00, 0x2c2e, 1}, + { 0x2c30, 0x2c5e, 1}, + { 0x2c60, 0x2c6f, 1}, + { 0x2c71, 0x2c7d, 1}, + { 0x2c80, 0x2ce4, 1}, + { 0x2d00, 0x2d25, 1}, + { 0x2d30, 0x2d65, 1}, + { 0x2d6f, 0x2d6f, 1}, + { 0x2d80, 0x2d96, 1}, + { 0x2da0, 0x2da6, 1}, + { 0x2da8, 0x2dae, 1}, + { 0x2db0, 0x2db6, 1}, + { 0x2db8, 0x2dbe, 1}, + { 0x2dc0, 0x2dc6, 1}, + { 0x2dc8, 0x2dce, 1}, + { 0x2dd0, 0x2dd6, 1}, + { 0x2dd8, 0x2dde, 1}, + { 0x2e2f, 0x2e2f, 1}, + { 0x3005, 0x3006, 1}, + { 0x3031, 0x3035, 1}, + { 0x303b, 0x303c, 1}, + { 0x3041, 0x3096, 1}, + { 0x309d, 0x309f, 1}, + { 0x30a1, 0x30fa, 1}, + { 0x30fc, 0x30ff, 1}, + { 0x3105, 0x312d, 1}, + { 0x3131, 0x318e, 1}, + { 0x31a0, 0x31b7, 1}, + { 0x31f0, 0x31ff, 1}, + { 0x3400, 0x4db5, 1}, + { 0x4e00, 0x9fc3, 1}, + { 0xa000, 0xa48c, 1}, + { 0xa500, 0xa60c, 1}, + { 0xa610, 0xa61f, 1}, + { 0xa62a, 0xa62b, 1}, + { 0xa640, 0xa65f, 1}, + { 0xa662, 0xa66e, 1}, + { 0xa67f, 0xa697, 1}, + { 0xa717, 0xa71f, 1}, + { 0xa722, 0xa788, 1}, + { 0xa78b, 0xa78c, 1}, + { 0xa7fb, 0xa801, 1}, + { 0xa803, 0xa805, 1}, + { 0xa807, 0xa80a, 1}, + { 0xa80c, 0xa822, 1}, + { 0xa840, 0xa873, 1}, + { 0xa882, 0xa8b3, 1}, + { 0xa90a, 0xa925, 1}, + { 0xa930, 0xa946, 1}, + { 0xaa00, 0xaa28, 1}, + { 0xaa40, 0xaa42, 1}, + { 0xaa44, 0xaa4b, 1}, + { 0xac00, 0xd7a3, 1}, + { 0xf900, 0xfa2d, 1}, + { 0xfa30, 0xfa6a, 1}, + { 0xfa70, 0xfad9, 1}, + { 0xfb00, 0xfb06, 1}, + { 0xfb13, 0xfb17, 1}, + { 0xfb1d, 0xfb1d, 1}, + { 0xfb1f, 0xfb28, 1}, + { 0xfb2a, 0xfb36, 1}, + { 0xfb38, 0xfb3c, 1}, + { 0xfb3e, 0xfb3e, 1}, + { 0xfb40, 0xfb41, 1}, + { 0xfb43, 0xfb44, 1}, + { 0xfb46, 0xfbb1, 1}, + { 0xfbd3, 0xfd3d, 1}, + { 0xfd50, 0xfd8f, 1}, + { 0xfd92, 0xfdc7, 1}, + { 0xfdf0, 0xfdfb, 1}, + { 0xfe70, 0xfe74, 1}, + { 0xfe76, 0xfefc, 1}, + { 0xff21, 0xff3a, 1}, + { 0xff41, 0xff5a, 1}, + { 0xff66, 0xffbe, 1}, + { 0xffc2, 0xffc7, 1}, + { 0xffca, 0xffcf, 1}, + { 0xffd2, 0xffd7, 1}, + { 0xffda, 0xffdc, 1}, + { 0x10000, 0x1000b, 1}, + { 0x1000d, 0x10026, 1}, + { 0x10028, 0x1003a, 1}, + { 0x1003c, 0x1003d, 1}, + { 0x1003f, 0x1004d, 1}, + { 0x10050, 0x1005d, 1}, + { 0x10080, 0x100fa, 1}, + { 0x10280, 0x1029c, 1}, + { 0x102a0, 0x102d0, 1}, + { 0x10300, 0x1031e, 1}, + { 0x10330, 0x10340, 1}, + { 0x10342, 0x10349, 1}, + { 0x10380, 0x1039d, 1}, + { 0x103a0, 0x103c3, 1}, + { 0x103c8, 0x103cf, 1}, + { 0x10400, 0x1049d, 1}, + { 0x10800, 0x10805, 1}, + { 0x10808, 0x10808, 1}, + { 0x1080a, 0x10835, 1}, + { 0x10837, 0x10838, 1}, + { 0x1083c, 0x1083f, 3}, + { 0x10900, 0x10915, 1}, + { 0x10920, 0x10939, 1}, + { 0x10a00, 0x10a00, 1}, + { 0x10a10, 0x10a13, 1}, + { 0x10a15, 0x10a17, 1}, + { 0x10a19, 0x10a33, 1}, + { 0x12000, 0x1236e, 1}, + { 0x1d400, 0x1d454, 1}, + { 0x1d456, 0x1d49c, 1}, + { 0x1d49e, 0x1d49f, 1}, + { 0x1d4a2, 0x1d4a2, 1}, + { 0x1d4a5, 0x1d4a6, 1}, + { 0x1d4a9, 0x1d4ac, 1}, + { 0x1d4ae, 0x1d4b9, 1}, + { 0x1d4bb, 0x1d4bb, 1}, + { 0x1d4bd, 0x1d4c3, 1}, + { 0x1d4c5, 0x1d505, 1}, + { 0x1d507, 0x1d50a, 1}, + { 0x1d50d, 0x1d514, 1}, + { 0x1d516, 0x1d51c, 1}, + { 0x1d51e, 0x1d539, 1}, + { 0x1d53b, 0x1d53e, 1}, + { 0x1d540, 0x1d544, 1}, + { 0x1d546, 0x1d546, 1}, + { 0x1d54a, 0x1d550, 1}, + { 0x1d552, 0x1d6a5, 1}, + { 0x1d6a8, 0x1d6c0, 1}, + { 0x1d6c2, 0x1d6da, 1}, + { 0x1d6dc, 0x1d6fa, 1}, + { 0x1d6fc, 0x1d714, 1}, + { 0x1d716, 0x1d734, 1}, + { 0x1d736, 0x1d74e, 1}, + { 0x1d750, 0x1d76e, 1}, + { 0x1d770, 0x1d788, 1}, + { 0x1d78a, 0x1d7a8, 1}, + { 0x1d7aa, 0x1d7c2, 1}, + { 0x1d7c4, 0x1d7cb, 1}, + { 0x20000, 0x2a6d6, 1}, + { 0x2f800, 0x2fa1d, 1}, +}; + +// A table of Unicode uppercase letters--Unicode code points +// classified as "Letter, uppercase". + +static const Unicode_range unicode_uppercase_letters[] = +{ + { 0x0041, 0x005a, 1}, + { 0x00c0, 0x00d6, 1}, + { 0x00d8, 0x00de, 1}, + { 0x0100, 0x0136, 2}, + { 0x0139, 0x0147, 2}, + { 0x014a, 0x0176, 2}, + { 0x0178, 0x0179, 1}, + { 0x017b, 0x017d, 2}, + { 0x0181, 0x0182, 1}, + { 0x0184, 0x0184, 1}, + { 0x0186, 0x0187, 1}, + { 0x0189, 0x018b, 1}, + { 0x018e, 0x0191, 1}, + { 0x0193, 0x0194, 1}, + { 0x0196, 0x0198, 1}, + { 0x019c, 0x019d, 1}, + { 0x019f, 0x01a0, 1}, + { 0x01a2, 0x01a4, 2}, + { 0x01a6, 0x01a7, 1}, + { 0x01a9, 0x01ac, 3}, + { 0x01ae, 0x01af, 1}, + { 0x01b1, 0x01b3, 1}, + { 0x01b5, 0x01b5, 1}, + { 0x01b7, 0x01b8, 1}, + { 0x01bc, 0x01c4, 8}, + { 0x01c7, 0x01cd, 3}, + { 0x01cf, 0x01db, 2}, + { 0x01de, 0x01ee, 2}, + { 0x01f1, 0x01f4, 3}, + { 0x01f6, 0x01f8, 1}, + { 0x01fa, 0x0232, 2}, + { 0x023a, 0x023b, 1}, + { 0x023d, 0x023e, 1}, + { 0x0241, 0x0241, 1}, + { 0x0243, 0x0246, 1}, + { 0x0248, 0x024e, 2}, + { 0x0370, 0x0372, 2}, + { 0x0376, 0x0386, 16}, + { 0x0388, 0x038a, 1}, + { 0x038c, 0x038c, 1}, + { 0x038e, 0x038f, 1}, + { 0x0391, 0x03a1, 1}, + { 0x03a3, 0x03ab, 1}, + { 0x03cf, 0x03cf, 1}, + { 0x03d2, 0x03d4, 1}, + { 0x03d8, 0x03ee, 2}, + { 0x03f4, 0x03f7, 3}, + { 0x03f9, 0x03fa, 1}, + { 0x03fd, 0x042f, 1}, + { 0x0460, 0x0480, 2}, + { 0x048a, 0x04be, 2}, + { 0x04c0, 0x04c1, 1}, + { 0x04c3, 0x04cd, 2}, + { 0x04d0, 0x0522, 2}, + { 0x0531, 0x0556, 1}, + { 0x10a0, 0x10c5, 1}, + { 0x1e00, 0x1e94, 2}, + { 0x1e9e, 0x1efe, 2}, + { 0x1f08, 0x1f0f, 1}, + { 0x1f18, 0x1f1d, 1}, + { 0x1f28, 0x1f2f, 1}, + { 0x1f38, 0x1f3f, 1}, + { 0x1f48, 0x1f4d, 1}, + { 0x1f59, 0x1f5f, 2}, + { 0x1f68, 0x1f6f, 1}, + { 0x1fb8, 0x1fbb, 1}, + { 0x1fc8, 0x1fcb, 1}, + { 0x1fd8, 0x1fdb, 1}, + { 0x1fe8, 0x1fec, 1}, + { 0x1ff8, 0x1ffb, 1}, + { 0x2102, 0x2107, 5}, + { 0x210b, 0x210d, 1}, + { 0x2110, 0x2112, 1}, + { 0x2115, 0x2115, 1}, + { 0x2119, 0x211d, 1}, + { 0x2124, 0x2128, 2}, + { 0x212a, 0x212d, 1}, + { 0x2130, 0x2133, 1}, + { 0x213e, 0x213f, 1}, + { 0x2145, 0x2183, 62}, + { 0x2c00, 0x2c2e, 1}, + { 0x2c60, 0x2c60, 1}, + { 0x2c62, 0x2c64, 1}, + { 0x2c67, 0x2c6b, 2}, + { 0x2c6d, 0x2c6f, 1}, + { 0x2c72, 0x2c75, 3}, + { 0x2c80, 0x2ce2, 2}, + { 0xa640, 0xa65e, 2}, + { 0xa662, 0xa66c, 2}, + { 0xa680, 0xa696, 2}, + { 0xa722, 0xa72e, 2}, + { 0xa732, 0xa76e, 2}, + { 0xa779, 0xa77b, 2}, + { 0xa77d, 0xa77e, 1}, + { 0xa780, 0xa786, 2}, + { 0xa78b, 0xa78b, 1}, + { 0xff21, 0xff3a, 1}, + { 0x10400, 0x10427, 1}, + { 0x1d400, 0x1d419, 1}, + { 0x1d434, 0x1d44d, 1}, + { 0x1d468, 0x1d481, 1}, + { 0x1d49c, 0x1d49c, 1}, + { 0x1d49e, 0x1d49f, 1}, + { 0x1d4a2, 0x1d4a2, 1}, + { 0x1d4a5, 0x1d4a6, 1}, + { 0x1d4a9, 0x1d4ac, 1}, + { 0x1d4ae, 0x1d4b5, 1}, + { 0x1d4d0, 0x1d4e9, 1}, + { 0x1d504, 0x1d505, 1}, + { 0x1d507, 0x1d50a, 1}, + { 0x1d50d, 0x1d514, 1}, + { 0x1d516, 0x1d51c, 1}, + { 0x1d538, 0x1d539, 1}, + { 0x1d53b, 0x1d53e, 1}, + { 0x1d540, 0x1d544, 1}, + { 0x1d546, 0x1d546, 1}, + { 0x1d54a, 0x1d550, 1}, + { 0x1d56c, 0x1d585, 1}, + { 0x1d5a0, 0x1d5b9, 1}, + { 0x1d5d4, 0x1d5ed, 1}, + { 0x1d608, 0x1d621, 1}, + { 0x1d63c, 0x1d655, 1}, + { 0x1d670, 0x1d689, 1}, + { 0x1d6a8, 0x1d6c0, 1}, + { 0x1d6e2, 0x1d6fa, 1}, + { 0x1d71c, 0x1d734, 1}, + { 0x1d756, 0x1d76e, 1}, + { 0x1d790, 0x1d7a8, 1}, + { 0x1d7ca, 0x1d7ca, 1}, +}; + +// Return true if C is in RANGES. + +bool +Lex::is_in_unicode_range(unsigned int c, const Unicode_range* ranges, + size_t range_size) +{ + if (c < 0x100) + { + // The common case is a small value, and we know that it will be + // in the first few entries of the table. Do a linear scan + // rather than a binary search. + for (size_t i = 0; i < range_size; ++i) + { + const Unicode_range* p = &ranges[i]; + if (c <= p->high) + { + if (c < p->low) + return false; + return (c - p->low) % p->stride == 0; + } + } + return false; + } + else + { + size_t lo = 0; + size_t hi = range_size; + while (lo < hi) + { + size_t mid = lo + (hi - lo) / 2; + const Unicode_range* p = &ranges[mid]; + if (c < p->low) + hi = mid; + else if (c > p->high) + lo = mid + 1; + else + return (c - p->low) % p->stride == 0; + } + return false; + } +} + +// Return whether C is a Unicode digit--a Unicode code point +// classified as "Digit". + +bool +Lex::is_unicode_digit(unsigned int c) +{ + return Lex::is_in_unicode_range(c, unicode_digits, + ARRAY_SIZE(unicode_digits)); +} + +// Return whether C is a Unicode letter--a Unicode code point +// classified as "Letter". + +bool +Lex::is_unicode_letter(unsigned int c) +{ + return Lex::is_in_unicode_range(c, unicode_letters, + ARRAY_SIZE(unicode_letters)); +} + +// Return whether C is a Unicode uppercase letter. a Unicode code +// point classified as "Letter, uppercase". + +bool +Lex::is_unicode_uppercase(unsigned int c) +{ + return Lex::is_in_unicode_range(c, unicode_uppercase_letters, + ARRAY_SIZE(unicode_uppercase_letters)); +} + +// Return whether the identifier NAME should be exported. NAME is a +// mangled name which includes only ASCII characters. + +bool +Lex::is_exported_name(const std::string& name) +{ + unsigned char c = name[0]; + if (c != '$') + return c >= 'A' && c <= 'Z'; + else + { + const char* p = name.data(); + size_t len = name.length(); + if (len < 2 || p[1] != 'U') + return false; + unsigned int ci = 0; + for (size_t i = 2; i < len && p[i] != '$'; ++i) + { + c = p[i]; + if (!hex_p(c)) + return false; + ci <<= 4; + ci |= hex_value(c); + } + return Lex::is_unicode_uppercase(ci); + } +} diff --git a/gcc/go/gofrontend/lex.h b/gcc/go/gofrontend/lex.h new file mode 100644 index 000000000..4202ed374 --- /dev/null +++ b/gcc/go/gofrontend/lex.h @@ -0,0 +1,449 @@ +// lex.h -- Go frontend lexer. -*- C++ -*- + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef GO_LEX_H +#define GO_LEX_H + +#include <gmp.h> +#include <mpfr.h> + +#include "operator.h" + +struct Unicode_range; + +// The keywords. These must be in sorted order, other than +// KEYWORD_INVALID. They must match the Keywords::mapping_ array in +// lex.cc. + +enum Keyword +{ + KEYWORD_INVALID, // Not a keyword. + KEYWORD_ASM, + KEYWORD_BREAK, + KEYWORD_CASE, + KEYWORD_CHAN, + KEYWORD_CONST, + KEYWORD_CONTINUE, + KEYWORD_DEFAULT, + KEYWORD_DEFER, + KEYWORD_ELSE, + KEYWORD_FALLTHROUGH, + KEYWORD_FOR, + KEYWORD_FUNC, + KEYWORD_GO, + KEYWORD_GOTO, + KEYWORD_IF, + KEYWORD_IMPORT, + KEYWORD_INTERFACE, + KEYWORD_MAP, + KEYWORD_PACKAGE, + KEYWORD_RANGE, + KEYWORD_RETURN, + KEYWORD_SELECT, + KEYWORD_STRUCT, + KEYWORD_SWITCH, + KEYWORD_TYPE, + KEYWORD_VAR +}; + +// A token returned from the lexer. + +class Token +{ + public: + // Token classification. + enum Classification + { + // Token is invalid. + TOKEN_INVALID, + // Token indicates end of input. + TOKEN_EOF, + // Token is a keyword. + TOKEN_KEYWORD, + // Token is an identifier. + TOKEN_IDENTIFIER, + // Token is a string of characters. + TOKEN_STRING, + // Token is an operator. + TOKEN_OPERATOR, + // Token is an integer. + TOKEN_INTEGER, + // Token is a floating point number. + TOKEN_FLOAT, + // Token is an imaginary number. + TOKEN_IMAGINARY + }; + + ~Token(); + Token(const Token&); + Token& operator=(const Token&); + + // Get token classification. + Classification + classification() const + { return this->classification_; } + + // Make a token for an invalid value. + static Token + make_invalid_token(source_location location) + { return Token(TOKEN_INVALID, location); } + + // Make a token representing end of file. + static Token + make_eof_token(source_location location) + { return Token(TOKEN_EOF, location); } + + // Make a keyword token. + static Token + make_keyword_token(Keyword keyword, source_location location) + { + Token tok(TOKEN_KEYWORD, location); + tok.u_.keyword = keyword; + return tok; + } + + // Make an identifier token. + static Token + make_identifier_token(const std::string& value, bool is_exported, + source_location location) + { + Token tok(TOKEN_IDENTIFIER, location); + tok.u_.identifier_value.name = new std::string(value); + tok.u_.identifier_value.is_exported = is_exported; + return tok; + } + + // Make a quoted string token. + static Token + make_string_token(const std::string& value, source_location location) + { + Token tok(TOKEN_STRING, location); + tok.u_.string_value = new std::string(value); + return tok; + } + + // Make an operator token. + static Token + make_operator_token(Operator op, source_location location) + { + Token tok(TOKEN_OPERATOR, location); + tok.u_.op = op; + return tok; + } + + // Make an integer token. + static Token + make_integer_token(mpz_t val, source_location location) + { + Token tok(TOKEN_INTEGER, location); + mpz_init(tok.u_.integer_value); + mpz_swap(tok.u_.integer_value, val); + return tok; + } + + // Make a float token. + static Token + make_float_token(mpfr_t val, source_location location) + { + Token tok(TOKEN_FLOAT, location); + mpfr_init(tok.u_.float_value); + mpfr_swap(tok.u_.float_value, val); + return tok; + } + + // Make a token for an imaginary number. + static Token + make_imaginary_token(mpfr_t val, source_location location) + { + Token tok(TOKEN_IMAGINARY, location); + mpfr_init(tok.u_.float_value); + mpfr_swap(tok.u_.float_value, val); + return tok; + } + + // Get the location of the token. + source_location + location() const + { return this->location_; } + + // Return whether this is an invalid token. + bool + is_invalid() const + { return this->classification_ == TOKEN_INVALID; } + + // Return whether this is the EOF token. + bool + is_eof() const + { return this->classification_ == TOKEN_EOF; } + + // Return the keyword value for a keyword token. + Keyword + keyword() const + { + gcc_assert(this->classification_ == TOKEN_KEYWORD); + return this->u_.keyword; + } + + // Return whether this is an identifier. + bool + is_identifier() const + { return this->classification_ == TOKEN_IDENTIFIER; } + + // Return the identifier. + const std::string& + identifier() const + { + gcc_assert(this->classification_ == TOKEN_IDENTIFIER); + return *this->u_.identifier_value.name; + } + + // Return whether the identifier is exported. + bool + is_identifier_exported() const + { + gcc_assert(this->classification_ == TOKEN_IDENTIFIER); + return this->u_.identifier_value.is_exported; + } + + // Return whether this is a string. + bool + is_string() const + { + return this->classification_ == TOKEN_STRING; + } + + // Return the value of a string. The returned value is a string of + // UTF-8 characters. + std::string + string_value() const + { + gcc_assert(this->classification_ == TOKEN_STRING); + return *this->u_.string_value; + } + + // Return the value of an integer. + const mpz_t* + integer_value() const + { + gcc_assert(this->classification_ == TOKEN_INTEGER); + return &this->u_.integer_value; + } + + // Return the value of a float. + const mpfr_t* + float_value() const + { + gcc_assert(this->classification_ == TOKEN_FLOAT); + return &this->u_.float_value; + } + + // Return the value of an imaginary number. + const mpfr_t* + imaginary_value() const + { + gcc_assert(this->classification_ == TOKEN_IMAGINARY); + return &this->u_.float_value; + } + + // Return the operator value for an operator token. + Operator + op() const + { + gcc_assert(this->classification_ == TOKEN_OPERATOR); + return this->u_.op; + } + + // Return whether this token is KEYWORD. + bool + is_keyword(Keyword keyword) const + { + return (this->classification_ == TOKEN_KEYWORD + && this->u_.keyword == keyword); + } + + // Return whether this token is OP. + bool + is_op(Operator op) const + { return this->classification_ == TOKEN_OPERATOR && this->u_.op == op; } + + // Print the token for debugging. + void + print(FILE*) const; + + private: + // Private constructor used by make_..._token functions above. + Token(Classification, source_location); + + // Clear the token. + void + clear(); + + // The token classification. + Classification classification_; + union + { + // The keyword value for TOKEN_KEYWORD. + Keyword keyword; + // The token value for TOKEN_IDENTIFIER. + struct + { + // The name of the identifier. This has been mangled to only + // include ASCII characters. + std::string* name; + // Whether this name should be exported. This is true if the + // first letter in the name is upper case. + bool is_exported; + } identifier_value; + // The string value for TOKEN_STRING. + std::string* string_value; + // The token value for TOKEN_INTEGER. + mpz_t integer_value; + // The token value for TOKEN_FLOAT or TOKEN_IMAGINARY. + mpfr_t float_value; + // The token value for TOKEN_OPERATOR or the keyword value + Operator op; + } u_; + // The source location. + source_location location_; +}; + +// The lexer itself. + +class Lex +{ + public: + Lex(const char* input_file_name, FILE* input_file); + + ~Lex(); + + // Return the next token. + Token + next_token(); + + // Return whether the identifier NAME should be exported. NAME is a + // mangled name which includes only ASCII characters. + static bool + is_exported_name(const std::string& name); + + // A helper function. Append V to STR. IS_CHARACTER is true if V + // is a Unicode character which should be converted into UTF-8, + // false if it is a byte value to be appended directly. The + // location is used to warn about an out of range character. + static void + append_char(unsigned int v, bool is_charater, std::string* str, + source_location); + + // A helper function. Fetch a UTF-8 character from STR and store it + // in *VALUE. Return the number of bytes read from STR. Return 0 + // if STR does not point to a valid UTF-8 character. + static int + fetch_char(const char* str, unsigned int *value); + + private: + ssize_t + get_line(); + + bool + require_line(); + + // The current location. + source_location + location() const; + + // A position CHARS column positions before the current location. + source_location + earlier_location(int chars) const; + + static bool + is_hex_digit(char); + + static unsigned char + octal_value(char c) + { return c - '0'; } + + Token + make_invalid_token() + { return Token::make_invalid_token(this->location()); } + + Token + make_eof_token() + { return Token::make_eof_token(this->location()); } + + Token + make_operator(Operator op, int chars) + { return Token::make_operator_token(op, this->earlier_location(chars)); } + + Token + gather_identifier(); + + static bool + could_be_exponent(const char*, const char*); + + Token + gather_number(); + + Token + gather_character(); + + Token + gather_string(); + + Token + gather_raw_string(); + + const char* + advance_one_utf8_char(const char*, unsigned int*, bool*); + + const char* + advance_one_char(const char*, bool, unsigned int*, bool*); + + static bool + is_unicode_digit(unsigned int c); + + static bool + is_unicode_letter(unsigned int c); + + static bool + is_unicode_uppercase(unsigned int c); + + static bool + is_in_unicode_range(unsigned int C, const Unicode_range* ranges, + size_t range_size); + + Operator + three_character_operator(char, char, char); + + Operator + two_character_operator(char, char); + + Operator + one_character_operator(char); + + bool + skip_c_comment(); + + void + skip_cpp_comment(); + + // The input file name. + const char* input_file_name_; + // The input file. + FILE* input_file_; + // The line buffer. This holds the current line. + char* linebuf_; + // The size of the line buffer. + size_t linebufsize_; + // The nmber of characters in the current line. + size_t linesize_; + // The current offset in linebuf_. + size_t lineoff_; + // The current line number. + size_t lineno_; + // Whether to add a semicolon if we see a newline now. + bool add_semi_at_eol_; +}; + +#endif // !defined(GO_LEX_H) diff --git a/gcc/go/gofrontend/operator.h b/gcc/go/gofrontend/operator.h new file mode 100644 index 000000000..f3e0fd074 --- /dev/null +++ b/gcc/go/gofrontend/operator.h @@ -0,0 +1,66 @@ +// operator.h -- Go frontend operators. -*- C++ -*- + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef GO_OPERATOR_H +#define GO_OPERATOR_H + +// The operators. + +enum Operator +{ + OPERATOR_INVALID, + OPERATOR_OROR, // || + OPERATOR_ANDAND, // && + OPERATOR_EQEQ, // == + OPERATOR_NOTEQ, // != + OPERATOR_LT, // < + OPERATOR_LE, // <= + OPERATOR_GT, // > + OPERATOR_GE, // >= + OPERATOR_PLUS, // + + OPERATOR_MINUS, // - + OPERATOR_OR, // | + OPERATOR_XOR, // ^ + OPERATOR_MULT, // * + OPERATOR_DIV, // / + OPERATOR_MOD, // % + OPERATOR_LSHIFT, // << + OPERATOR_RSHIFT, // >> + OPERATOR_AND, // & + OPERATOR_NOT, // ! + OPERATOR_BITCLEAR, // &^ + OPERATOR_CHANOP, // <- + + OPERATOR_EQ, // = + OPERATOR_PLUSEQ, // += + OPERATOR_MINUSEQ, // -= + OPERATOR_OREQ, // |= + OPERATOR_XOREQ, // ^= + OPERATOR_MULTEQ, // *= + OPERATOR_DIVEQ, // /= + OPERATOR_MODEQ, // %= + OPERATOR_LSHIFTEQ, // <<= + OPERATOR_RSHIFTEQ, // >>= + OPERATOR_ANDEQ, // &= + OPERATOR_BITCLEAREQ, // &^= + OPERATOR_PLUSPLUS, // ++ + OPERATOR_MINUSMINUS, // -- + + OPERATOR_COLON, // : + OPERATOR_COLONEQ, // := + OPERATOR_SEMICOLON, // ; + OPERATOR_DOT, // . + OPERATOR_ELLIPSIS, // ... + OPERATOR_COMMA, // , + OPERATOR_LPAREN, // ( + OPERATOR_RPAREN, // ) + OPERATOR_LCURLY, // { + OPERATOR_RCURLY, // } + OPERATOR_LSQUARE, // [ + OPERATOR_RSQUARE // ] +}; + +#endif // !defined(GO_OPERATOR_H) diff --git a/gcc/go/gofrontend/parse.cc b/gcc/go/gofrontend/parse.cc new file mode 100644 index 000000000..7c03870e8 --- /dev/null +++ b/gcc/go/gofrontend/parse.cc @@ -0,0 +1,4906 @@ +// parse.cc -- Go frontend parser. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include "lex.h" +#include "gogo.h" +#include "types.h" +#include "statements.h" +#include "expressions.h" +#include "parse.h" + +// Struct Parse::Enclosing_var_comparison. + +// Return true if v1 should be considered to be less than v2. + +bool +Parse::Enclosing_var_comparison::operator()(const Enclosing_var& v1, + const Enclosing_var& v2) +{ + if (v1.var() == v2.var()) + return false; + + const std::string& n1(v1.var()->name()); + const std::string& n2(v2.var()->name()); + int i = n1.compare(n2); + if (i < 0) + return true; + else if (i > 0) + return false; + + // If we get here it means that a single nested function refers to + // two different variables defined in enclosing functions, and both + // variables have the same name. I think this is impossible. + gcc_unreachable(); +} + +// Class Parse. + +Parse::Parse(Lex* lex, Gogo* gogo) + : lex_(lex), + token_(Token::make_invalid_token(0)), + unget_token_(Token::make_invalid_token(0)), + unget_token_valid_(false), + gogo_(gogo), + break_stack_(NULL), + continue_stack_(NULL), + iota_(0), + enclosing_vars_() +{ +} + +// Return the current token. + +const Token* +Parse::peek_token() +{ + if (this->unget_token_valid_) + return &this->unget_token_; + if (this->token_.is_invalid()) + this->token_ = this->lex_->next_token(); + return &this->token_; +} + +// Advance to the next token and return it. + +const Token* +Parse::advance_token() +{ + if (this->unget_token_valid_) + { + this->unget_token_valid_ = false; + if (!this->token_.is_invalid()) + return &this->token_; + } + this->token_ = this->lex_->next_token(); + return &this->token_; +} + +// Push a token back on the input stream. + +void +Parse::unget_token(const Token& token) +{ + gcc_assert(!this->unget_token_valid_); + this->unget_token_ = token; + this->unget_token_valid_ = true; +} + +// The location of the current token. + +source_location +Parse::location() +{ + return this->peek_token()->location(); +} + +// IdentifierList = identifier { "," identifier } . + +void +Parse::identifier_list(Typed_identifier_list* til) +{ + const Token* token = this->peek_token(); + while (true) + { + if (!token->is_identifier()) + { + error_at(this->location(), "expected identifier"); + return; + } + std::string name = + this->gogo_->pack_hidden_name(token->identifier(), + token->is_identifier_exported()); + til->push_back(Typed_identifier(name, NULL, token->location())); + token = this->advance_token(); + if (!token->is_op(OPERATOR_COMMA)) + return; + token = this->advance_token(); + } +} + +// ExpressionList = Expression { "," Expression } . + +// If MAY_BE_SINK is true, the expressions in the list may be "_". + +Expression_list* +Parse::expression_list(Expression* first, bool may_be_sink) +{ + Expression_list* ret = new Expression_list(); + if (first != NULL) + ret->push_back(first); + while (true) + { + ret->push_back(this->expression(PRECEDENCE_NORMAL, may_be_sink, true, + NULL)); + + const Token* token = this->peek_token(); + if (!token->is_op(OPERATOR_COMMA)) + return ret; + + // Most expression lists permit a trailing comma. + source_location location = token->location(); + this->advance_token(); + if (!this->expression_may_start_here()) + { + this->unget_token(Token::make_operator_token(OPERATOR_COMMA, + location)); + return ret; + } + } +} + +// QualifiedIdent = [ PackageName "." ] identifier . +// PackageName = identifier . + +// This sets *PNAME to the identifier and sets *PPACKAGE to the +// package or NULL if there isn't one. This returns true on success, +// false on failure in which case it will have emitted an error +// message. + +bool +Parse::qualified_ident(std::string* pname, Named_object** ppackage) +{ + const Token* token = this->peek_token(); + if (!token->is_identifier()) + { + error_at(this->location(), "expected identifier"); + return false; + } + + std::string name = token->identifier(); + bool is_exported = token->is_identifier_exported(); + name = this->gogo_->pack_hidden_name(name, is_exported); + + token = this->advance_token(); + if (!token->is_op(OPERATOR_DOT)) + { + *pname = name; + *ppackage = NULL; + return true; + } + + Named_object* package = this->gogo_->lookup(name, NULL); + if (package == NULL || !package->is_package()) + { + error_at(this->location(), "expected package"); + // We expect . IDENTIFIER; skip both. + if (this->advance_token()->is_identifier()) + this->advance_token(); + return false; + } + + package->package_value()->set_used(); + + token = this->advance_token(); + if (!token->is_identifier()) + { + error_at(this->location(), "expected identifier"); + return false; + } + + name = token->identifier(); + + if (name == "_") + { + error_at(this->location(), "invalid use of %<_%>"); + name = "blank"; + } + + if (package->name() == this->gogo_->package_name()) + name = this->gogo_->pack_hidden_name(name, + token->is_identifier_exported()); + + *pname = name; + *ppackage = package; + + this->advance_token(); + + return true; +} + +// Type = TypeName | TypeLit | "(" Type ")" . +// TypeLit = +// ArrayType | StructType | PointerType | FunctionType | InterfaceType | +// SliceType | MapType | ChannelType . + +Type* +Parse::type() +{ + const Token* token = this->peek_token(); + if (token->is_identifier()) + return this->type_name(true); + else if (token->is_op(OPERATOR_LSQUARE)) + return this->array_type(false); + else if (token->is_keyword(KEYWORD_CHAN) + || token->is_op(OPERATOR_CHANOP)) + return this->channel_type(); + else if (token->is_keyword(KEYWORD_INTERFACE)) + return this->interface_type(); + else if (token->is_keyword(KEYWORD_FUNC)) + { + source_location location = token->location(); + this->advance_token(); + Type* type = this->signature(NULL, location); + if (type == NULL) + return Type::make_error_type(); + return type; + } + else if (token->is_keyword(KEYWORD_MAP)) + return this->map_type(); + else if (token->is_keyword(KEYWORD_STRUCT)) + return this->struct_type(); + else if (token->is_op(OPERATOR_MULT)) + return this->pointer_type(); + else if (token->is_op(OPERATOR_LPAREN)) + { + this->advance_token(); + Type* ret = this->type(); + if (this->peek_token()->is_op(OPERATOR_RPAREN)) + this->advance_token(); + else + { + if (!ret->is_error_type()) + error_at(this->location(), "expected %<)%>"); + } + return ret; + } + else + { + error_at(token->location(), "expected type"); + return Type::make_error_type(); + } +} + +bool +Parse::type_may_start_here() +{ + const Token* token = this->peek_token(); + return (token->is_identifier() + || token->is_op(OPERATOR_LSQUARE) + || token->is_op(OPERATOR_CHANOP) + || token->is_keyword(KEYWORD_CHAN) + || token->is_keyword(KEYWORD_INTERFACE) + || token->is_keyword(KEYWORD_FUNC) + || token->is_keyword(KEYWORD_MAP) + || token->is_keyword(KEYWORD_STRUCT) + || token->is_op(OPERATOR_MULT) + || token->is_op(OPERATOR_LPAREN)); +} + +// TypeName = QualifiedIdent . + +// If MAY_BE_NIL is true, then an identifier with the value of the +// predefined constant nil is accepted, returning the nil type. + +Type* +Parse::type_name(bool issue_error) +{ + source_location location = this->location(); + + std::string name; + Named_object* package; + if (!this->qualified_ident(&name, &package)) + return Type::make_error_type(); + + Named_object* named_object; + if (package == NULL) + named_object = this->gogo_->lookup(name, NULL); + else + { + named_object = package->package_value()->lookup(name); + if (named_object == NULL + && issue_error + && package->name() != this->gogo_->package_name()) + { + // Check whether the name is there but hidden. + std::string s = ('.' + package->package_value()->unique_prefix() + + '.' + package->package_value()->name() + + '.' + name); + named_object = package->package_value()->lookup(s); + if (named_object != NULL) + { + const std::string& packname(package->package_value()->name()); + error_at(location, "invalid reference to hidden type %<%s.%s%>", + Gogo::message_name(packname).c_str(), + Gogo::message_name(name).c_str()); + issue_error = false; + } + } + } + + bool ok = true; + if (named_object == NULL) + { + if (package != NULL) + ok = false; + else + named_object = this->gogo_->add_unknown_name(name, location); + } + else if (named_object->is_type()) + { + if (!named_object->type_value()->is_visible()) + ok = false; + } + else if (named_object->is_unknown() || named_object->is_type_declaration()) + ; + else + ok = false; + + if (!ok) + { + if (issue_error) + error_at(location, "expected type"); + return Type::make_error_type(); + } + + if (named_object->is_type()) + return named_object->type_value(); + else if (named_object->is_unknown() || named_object->is_type_declaration()) + return Type::make_forward_declaration(named_object); + else + gcc_unreachable(); +} + +// ArrayType = "[" [ ArrayLength ] "]" ElementType . +// ArrayLength = Expression . +// ElementType = CompleteType . + +Type* +Parse::array_type(bool may_use_ellipsis) +{ + gcc_assert(this->peek_token()->is_op(OPERATOR_LSQUARE)); + const Token* token = this->advance_token(); + + Expression* length = NULL; + if (token->is_op(OPERATOR_RSQUARE)) + this->advance_token(); + else + { + if (!token->is_op(OPERATOR_ELLIPSIS)) + length = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + else if (may_use_ellipsis) + { + // An ellipsis is used in composite literals to represent a + // fixed array of the size of the number of elements. We + // use a length of nil to represent this, and change the + // length when parsing the composite literal. + length = Expression::make_nil(this->location()); + this->advance_token(); + } + else + { + error_at(this->location(), + "use of %<[...]%> outside of array literal"); + length = Expression::make_error(this->location()); + this->advance_token(); + } + if (!this->peek_token()->is_op(OPERATOR_RSQUARE)) + { + error_at(this->location(), "expected %<]%>"); + return Type::make_error_type(); + } + this->advance_token(); + } + + Type* element_type = this->type(); + + return Type::make_array_type(element_type, length); +} + +// MapType = "map" "[" KeyType "]" ValueType . +// KeyType = CompleteType . +// ValueType = CompleteType . + +Type* +Parse::map_type() +{ + source_location location = this->location(); + gcc_assert(this->peek_token()->is_keyword(KEYWORD_MAP)); + if (!this->advance_token()->is_op(OPERATOR_LSQUARE)) + { + error_at(this->location(), "expected %<[%>"); + return Type::make_error_type(); + } + this->advance_token(); + + Type* key_type = this->type(); + + if (!this->peek_token()->is_op(OPERATOR_RSQUARE)) + { + error_at(this->location(), "expected %<]%>"); + return Type::make_error_type(); + } + this->advance_token(); + + Type* value_type = this->type(); + + if (key_type->is_error_type() || value_type->is_error_type()) + return Type::make_error_type(); + + return Type::make_map_type(key_type, value_type, location); +} + +// StructType = "struct" "{" { FieldDecl ";" } "}" . + +Type* +Parse::struct_type() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_STRUCT)); + source_location location = this->location(); + if (!this->advance_token()->is_op(OPERATOR_LCURLY)) + { + source_location token_loc = this->location(); + if (this->peek_token()->is_op(OPERATOR_SEMICOLON) + && this->advance_token()->is_op(OPERATOR_LCURLY)) + error_at(token_loc, "unexpected semicolon or newline before %<{%>"); + else + { + error_at(this->location(), "expected %<{%>"); + return Type::make_error_type(); + } + } + this->advance_token(); + + Struct_field_list* sfl = new Struct_field_list; + while (!this->peek_token()->is_op(OPERATOR_RCURLY)) + { + this->field_decl(sfl); + if (this->peek_token()->is_op(OPERATOR_SEMICOLON)) + this->advance_token(); + else if (!this->peek_token()->is_op(OPERATOR_RCURLY)) + { + error_at(this->location(), "expected %<;%> or %<}%> or newline"); + if (!this->skip_past_error(OPERATOR_RCURLY)) + return Type::make_error_type(); + } + } + this->advance_token(); + + for (Struct_field_list::const_iterator pi = sfl->begin(); + pi != sfl->end(); + ++pi) + { + if (pi->type()->is_error_type()) + return pi->type(); + for (Struct_field_list::const_iterator pj = pi + 1; + pj != sfl->end(); + ++pj) + { + if (pi->field_name() == pj->field_name() + && !Gogo::is_sink_name(pi->field_name())) + error_at(pi->location(), "duplicate field name %<%s%>", + Gogo::message_name(pi->field_name()).c_str()); + } + } + + return Type::make_struct_type(sfl, location); +} + +// FieldDecl = (IdentifierList CompleteType | TypeName) [ Tag ] . +// Tag = string_lit . + +void +Parse::field_decl(Struct_field_list* sfl) +{ + const Token* token = this->peek_token(); + source_location location = token->location(); + bool is_anonymous; + bool is_anonymous_pointer; + if (token->is_op(OPERATOR_MULT)) + { + is_anonymous = true; + is_anonymous_pointer = true; + } + else if (token->is_identifier()) + { + std::string id = token->identifier(); + bool is_id_exported = token->is_identifier_exported(); + source_location id_location = token->location(); + token = this->advance_token(); + is_anonymous = (token->is_op(OPERATOR_SEMICOLON) + || token->is_op(OPERATOR_RCURLY) + || token->is_op(OPERATOR_DOT) + || token->is_string()); + is_anonymous_pointer = false; + this->unget_token(Token::make_identifier_token(id, is_id_exported, + id_location)); + } + else + { + error_at(this->location(), "expected field name"); + while (!token->is_op(OPERATOR_SEMICOLON) + && !token->is_op(OPERATOR_RCURLY) + && !token->is_eof()) + token = this->advance_token(); + return; + } + + if (is_anonymous) + { + if (is_anonymous_pointer) + { + this->advance_token(); + if (!this->peek_token()->is_identifier()) + { + error_at(this->location(), "expected field name"); + while (!token->is_op(OPERATOR_SEMICOLON) + && !token->is_op(OPERATOR_RCURLY) + && !token->is_eof()) + token = this->advance_token(); + return; + } + } + Type* type = this->type_name(true); + + std::string tag; + if (this->peek_token()->is_string()) + { + tag = this->peek_token()->string_value(); + this->advance_token(); + } + + if (!type->is_error_type()) + { + if (is_anonymous_pointer) + type = Type::make_pointer_type(type); + sfl->push_back(Struct_field(Typed_identifier("", type, location))); + if (!tag.empty()) + sfl->back().set_tag(tag); + } + } + else + { + Typed_identifier_list til; + while (true) + { + token = this->peek_token(); + if (!token->is_identifier()) + { + error_at(this->location(), "expected identifier"); + return; + } + std::string name = + this->gogo_->pack_hidden_name(token->identifier(), + token->is_identifier_exported()); + til.push_back(Typed_identifier(name, NULL, token->location())); + if (!this->advance_token()->is_op(OPERATOR_COMMA)) + break; + this->advance_token(); + } + + Type* type = this->type(); + + std::string tag; + if (this->peek_token()->is_string()) + { + tag = this->peek_token()->string_value(); + this->advance_token(); + } + + for (Typed_identifier_list::iterator p = til.begin(); + p != til.end(); + ++p) + { + p->set_type(type); + sfl->push_back(Struct_field(*p)); + if (!tag.empty()) + sfl->back().set_tag(tag); + } + } +} + +// PointerType = "*" Type . + +Type* +Parse::pointer_type() +{ + gcc_assert(this->peek_token()->is_op(OPERATOR_MULT)); + this->advance_token(); + Type* type = this->type(); + if (type->is_error_type()) + return type; + return Type::make_pointer_type(type); +} + +// ChannelType = Channel | SendChannel | RecvChannel . +// Channel = "chan" ElementType . +// SendChannel = "chan" "<-" ElementType . +// RecvChannel = "<-" "chan" ElementType . + +Type* +Parse::channel_type() +{ + const Token* token = this->peek_token(); + bool send = true; + bool receive = true; + if (token->is_op(OPERATOR_CHANOP)) + { + if (!this->advance_token()->is_keyword(KEYWORD_CHAN)) + { + error_at(this->location(), "expected %<chan%>"); + return Type::make_error_type(); + } + send = false; + this->advance_token(); + } + else + { + gcc_assert(token->is_keyword(KEYWORD_CHAN)); + if (this->advance_token()->is_op(OPERATOR_CHANOP)) + { + receive = false; + this->advance_token(); + } + } + Type* element_type = this->type(); + return Type::make_channel_type(send, receive, element_type); +} + +// Signature = Parameters [ Result ] . + +// RECEIVER is the receiver if there is one, or NULL. LOCATION is the +// location of the start of the type. + +// This returns NULL on a parse error. + +Function_type* +Parse::signature(Typed_identifier* receiver, source_location location) +{ + bool is_varargs = false; + Typed_identifier_list* params; + bool params_ok = this->parameters(¶ms, &is_varargs); + + Typed_identifier_list* result = NULL; + if (this->peek_token()->is_op(OPERATOR_LPAREN) + || this->type_may_start_here()) + { + if (!this->result(&result)) + return NULL; + } + + if (!params_ok) + return NULL; + + Function_type* ret = Type::make_function_type(receiver, params, result, + location); + if (is_varargs) + ret->set_is_varargs(); + return ret; +} + +// Parameters = "(" [ ParameterList [ "," ] ] ")" . + +// This returns false on a parse error. + +bool +Parse::parameters(Typed_identifier_list** pparams, bool* is_varargs) +{ + *pparams = NULL; + + if (!this->peek_token()->is_op(OPERATOR_LPAREN)) + { + error_at(this->location(), "expected %<(%>"); + return false; + } + + Typed_identifier_list* params = NULL; + bool saw_error = false; + + const Token* token = this->advance_token(); + if (!token->is_op(OPERATOR_RPAREN)) + { + params = this->parameter_list(is_varargs); + if (params == NULL) + saw_error = true; + token = this->peek_token(); + } + + // The optional trailing comma is picked up in parameter_list. + + if (!token->is_op(OPERATOR_RPAREN)) + error_at(this->location(), "expected %<)%>"); + else + this->advance_token(); + + if (saw_error) + return false; + + *pparams = params; + return true; +} + +// ParameterList = ParameterDecl { "," ParameterDecl } . + +// This sets *IS_VARARGS if the list ends with an ellipsis. +// IS_VARARGS will be NULL if varargs are not permitted. + +// We pick up an optional trailing comma. + +// This returns NULL if some error is seen. + +Typed_identifier_list* +Parse::parameter_list(bool* is_varargs) +{ + source_location location = this->location(); + Typed_identifier_list* ret = new Typed_identifier_list(); + + bool saw_error = false; + + // If we see an identifier and then a comma, then we don't know + // whether we are looking at a list of identifiers followed by a + // type, or a list of types given by name. We have to do an + // arbitrary lookahead to figure it out. + + bool parameters_have_names; + const Token* token = this->peek_token(); + if (!token->is_identifier()) + { + // This must be a type which starts with something like '*'. + parameters_have_names = false; + } + else + { + std::string name = token->identifier(); + bool is_exported = token->is_identifier_exported(); + source_location location = token->location(); + token = this->advance_token(); + if (!token->is_op(OPERATOR_COMMA)) + { + if (token->is_op(OPERATOR_DOT)) + { + // This is a qualified identifier, which must turn out + // to be a type. + parameters_have_names = false; + } + else if (token->is_op(OPERATOR_RPAREN)) + { + // A single identifier followed by a parenthesis must be + // a type name. + parameters_have_names = false; + } + else + { + // An identifier followed by something other than a + // comma or a dot or a right parenthesis must be a + // parameter name followed by a type. + parameters_have_names = true; + } + + this->unget_token(Token::make_identifier_token(name, is_exported, + location)); + } + else + { + // An identifier followed by a comma may be the first in a + // list of parameter names followed by a type, or it may be + // the first in a list of types without parameter names. To + // find out we gather as many identifiers separated by + // commas as we can. + std::string id_name = this->gogo_->pack_hidden_name(name, + is_exported); + ret->push_back(Typed_identifier(id_name, NULL, location)); + bool just_saw_comma = true; + while (this->advance_token()->is_identifier()) + { + name = this->peek_token()->identifier(); + is_exported = this->peek_token()->is_identifier_exported(); + location = this->peek_token()->location(); + id_name = this->gogo_->pack_hidden_name(name, is_exported); + ret->push_back(Typed_identifier(id_name, NULL, location)); + if (!this->advance_token()->is_op(OPERATOR_COMMA)) + { + just_saw_comma = false; + break; + } + } + + if (just_saw_comma) + { + // We saw ID1 "," ID2 "," followed by something which + // was not an identifier. We must be seeing the start + // of a type, and ID1 and ID2 must be types, and the + // parameters don't have names. + parameters_have_names = false; + } + else if (this->peek_token()->is_op(OPERATOR_RPAREN)) + { + // We saw ID1 "," ID2 ")". ID1 and ID2 must be types, + // and the parameters don't have names. + parameters_have_names = false; + } + else if (this->peek_token()->is_op(OPERATOR_DOT)) + { + // We saw ID1 "," ID2 ".". ID2 must be a package name, + // ID1 must be a type, and the parameters don't have + // names. + parameters_have_names = false; + this->unget_token(Token::make_identifier_token(name, is_exported, + location)); + ret->pop_back(); + just_saw_comma = true; + } + else + { + // We saw ID1 "," ID2 followed by something other than + // ",", ".", or ")". We must be looking at the start of + // a type, and ID1 and ID2 must be parameter names. + parameters_have_names = true; + } + + if (parameters_have_names) + { + gcc_assert(!just_saw_comma); + // We have just seen ID1, ID2 xxx. + Type* type; + if (!this->peek_token()->is_op(OPERATOR_ELLIPSIS)) + type = this->type(); + else + { + error_at(this->location(), "%<...%> only permits one name"); + saw_error = true; + this->advance_token(); + type = this->type(); + } + for (size_t i = 0; i < ret->size(); ++i) + ret->set_type(i, type); + if (!this->peek_token()->is_op(OPERATOR_COMMA)) + return saw_error ? NULL : ret; + if (this->advance_token()->is_op(OPERATOR_RPAREN)) + return saw_error ? NULL : ret; + } + else + { + Typed_identifier_list* tret = new Typed_identifier_list(); + for (Typed_identifier_list::const_iterator p = ret->begin(); + p != ret->end(); + ++p) + { + Named_object* no = this->gogo_->lookup(p->name(), NULL); + Type* type; + if (no == NULL) + no = this->gogo_->add_unknown_name(p->name(), + p->location()); + + if (no->is_type()) + type = no->type_value(); + else if (no->is_unknown() || no->is_type_declaration()) + type = Type::make_forward_declaration(no); + else + { + error_at(p->location(), "expected %<%s%> to be a type", + Gogo::message_name(p->name()).c_str()); + saw_error = true; + type = Type::make_error_type(); + } + tret->push_back(Typed_identifier("", type, p->location())); + } + delete ret; + ret = tret; + if (!just_saw_comma + || this->peek_token()->is_op(OPERATOR_RPAREN)) + return saw_error ? NULL : ret; + } + } + } + + bool mix_error = false; + this->parameter_decl(parameters_have_names, ret, is_varargs, &mix_error); + while (this->peek_token()->is_op(OPERATOR_COMMA)) + { + if (is_varargs != NULL && *is_varargs) + { + error_at(this->location(), "%<...%> must be last parameter"); + saw_error = true; + } + if (this->advance_token()->is_op(OPERATOR_RPAREN)) + break; + this->parameter_decl(parameters_have_names, ret, is_varargs, &mix_error); + } + if (mix_error) + { + error_at(location, "invalid named/anonymous mix"); + saw_error = true; + } + if (saw_error) + { + delete ret; + return NULL; + } + return ret; +} + +// ParameterDecl = [ IdentifierList ] [ "..." ] Type . + +void +Parse::parameter_decl(bool parameters_have_names, + Typed_identifier_list* til, + bool* is_varargs, + bool* mix_error) +{ + if (!parameters_have_names) + { + Type* type; + source_location location = this->location(); + if (!this->peek_token()->is_identifier()) + { + if (!this->peek_token()->is_op(OPERATOR_ELLIPSIS)) + type = this->type(); + else + { + if (is_varargs == NULL) + error_at(this->location(), "invalid use of %<...%>"); + else + *is_varargs = true; + this->advance_token(); + if (is_varargs == NULL + && this->peek_token()->is_op(OPERATOR_RPAREN)) + type = Type::make_error_type(); + else + { + Type* element_type = this->type(); + type = Type::make_array_type(element_type, NULL); + } + } + } + else + { + type = this->type_name(false); + if (type->is_error_type() + || (!this->peek_token()->is_op(OPERATOR_COMMA) + && !this->peek_token()->is_op(OPERATOR_RPAREN))) + { + *mix_error = true; + while (!this->peek_token()->is_op(OPERATOR_COMMA) + && !this->peek_token()->is_op(OPERATOR_RPAREN)) + this->advance_token(); + } + } + if (!type->is_error_type()) + til->push_back(Typed_identifier("", type, location)); + } + else + { + size_t orig_count = til->size(); + if (this->peek_token()->is_identifier()) + this->identifier_list(til); + else + *mix_error = true; + size_t new_count = til->size(); + + Type* type; + if (!this->peek_token()->is_op(OPERATOR_ELLIPSIS)) + type = this->type(); + else + { + if (is_varargs == NULL) + error_at(this->location(), "invalid use of %<...%>"); + else if (new_count > orig_count + 1) + error_at(this->location(), "%<...%> only permits one name"); + else + *is_varargs = true; + this->advance_token(); + Type* element_type = this->type(); + type = Type::make_array_type(element_type, NULL); + } + for (size_t i = orig_count; i < new_count; ++i) + til->set_type(i, type); + } +} + +// Result = Parameters | Type . + +// This returns false on a parse error. + +bool +Parse::result(Typed_identifier_list** presults) +{ + if (this->peek_token()->is_op(OPERATOR_LPAREN)) + return this->parameters(presults, NULL); + else + { + source_location location = this->location(); + Type* type = this->type(); + if (type->is_error_type()) + { + *presults = NULL; + return false; + } + Typed_identifier_list* til = new Typed_identifier_list(); + til->push_back(Typed_identifier("", type, location)); + *presults = til; + return true; + } +} + +// Block = "{" [ StatementList ] "}" . + +// Returns the location of the closing brace. + +source_location +Parse::block() +{ + if (!this->peek_token()->is_op(OPERATOR_LCURLY)) + { + source_location loc = this->location(); + if (this->peek_token()->is_op(OPERATOR_SEMICOLON) + && this->advance_token()->is_op(OPERATOR_LCURLY)) + error_at(loc, "unexpected semicolon or newline before %<{%>"); + else + { + error_at(this->location(), "expected %<{%>"); + return UNKNOWN_LOCATION; + } + } + + const Token* token = this->advance_token(); + + if (!token->is_op(OPERATOR_RCURLY)) + { + this->statement_list(); + token = this->peek_token(); + if (!token->is_op(OPERATOR_RCURLY)) + { + if (!token->is_eof() || !saw_errors()) + error_at(this->location(), "expected %<}%>"); + + // Skip ahead to the end of the block, in hopes of avoiding + // lots of meaningless errors. + source_location ret = token->location(); + int nest = 0; + while (!token->is_eof()) + { + if (token->is_op(OPERATOR_LCURLY)) + ++nest; + else if (token->is_op(OPERATOR_RCURLY)) + { + --nest; + if (nest < 0) + { + this->advance_token(); + break; + } + } + token = this->advance_token(); + ret = token->location(); + } + return ret; + } + } + + source_location ret = token->location(); + this->advance_token(); + return ret; +} + +// InterfaceType = "interface" "{" [ MethodSpecList ] "}" . +// MethodSpecList = MethodSpec { ";" MethodSpec } [ ";" ] . + +Type* +Parse::interface_type() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_INTERFACE)); + source_location location = this->location(); + + if (!this->advance_token()->is_op(OPERATOR_LCURLY)) + { + source_location token_loc = this->location(); + if (this->peek_token()->is_op(OPERATOR_SEMICOLON) + && this->advance_token()->is_op(OPERATOR_LCURLY)) + error_at(token_loc, "unexpected semicolon or newline before %<{%>"); + else + { + error_at(this->location(), "expected %<{%>"); + return Type::make_error_type(); + } + } + this->advance_token(); + + Typed_identifier_list* methods = new Typed_identifier_list(); + if (!this->peek_token()->is_op(OPERATOR_RCURLY)) + { + this->method_spec(methods); + while (this->peek_token()->is_op(OPERATOR_SEMICOLON)) + { + if (this->advance_token()->is_op(OPERATOR_RCURLY)) + break; + this->method_spec(methods); + } + if (!this->peek_token()->is_op(OPERATOR_RCURLY)) + { + error_at(this->location(), "expected %<}%>"); + while (!this->advance_token()->is_op(OPERATOR_RCURLY)) + { + if (this->peek_token()->is_eof()) + return Type::make_error_type(); + } + } + } + this->advance_token(); + + if (methods->empty()) + { + delete methods; + methods = NULL; + } + + Interface_type* ret = Type::make_interface_type(methods, location); + this->gogo_->record_interface_type(ret); + return ret; +} + +// MethodSpec = MethodName Signature | InterfaceTypeName . +// MethodName = identifier . +// InterfaceTypeName = TypeName . + +void +Parse::method_spec(Typed_identifier_list* methods) +{ + const Token* token = this->peek_token(); + if (!token->is_identifier()) + { + error_at(this->location(), "expected identifier"); + return; + } + + std::string name = token->identifier(); + bool is_exported = token->is_identifier_exported(); + source_location location = token->location(); + + if (this->advance_token()->is_op(OPERATOR_LPAREN)) + { + // This is a MethodName. + name = this->gogo_->pack_hidden_name(name, is_exported); + Type* type = this->signature(NULL, location); + if (type == NULL) + return; + methods->push_back(Typed_identifier(name, type, location)); + } + else + { + this->unget_token(Token::make_identifier_token(name, is_exported, + location)); + Type* type = this->type_name(false); + if (type->is_error_type() + || (!this->peek_token()->is_op(OPERATOR_SEMICOLON) + && !this->peek_token()->is_op(OPERATOR_RCURLY))) + { + if (this->peek_token()->is_op(OPERATOR_COMMA)) + error_at(this->location(), + "name list not allowed in interface type"); + else + error_at(location, "expected signature or type name"); + token = this->peek_token(); + while (!token->is_eof() + && !token->is_op(OPERATOR_SEMICOLON) + && !token->is_op(OPERATOR_RCURLY)) + token = this->advance_token(); + return; + } + // This must be an interface type, but we can't check that now. + // We check it and pull out the methods in + // Interface_type::do_verify. + methods->push_back(Typed_identifier("", type, location)); + } +} + +// Declaration = ConstDecl | TypeDecl | VarDecl | FunctionDecl | MethodDecl . + +void +Parse::declaration() +{ + const Token* token = this->peek_token(); + if (token->is_keyword(KEYWORD_CONST)) + this->const_decl(); + else if (token->is_keyword(KEYWORD_TYPE)) + this->type_decl(); + else if (token->is_keyword(KEYWORD_VAR)) + this->var_decl(); + else if (token->is_keyword(KEYWORD_FUNC)) + this->function_decl(); + else + { + error_at(this->location(), "expected declaration"); + this->advance_token(); + } +} + +bool +Parse::declaration_may_start_here() +{ + const Token* token = this->peek_token(); + return (token->is_keyword(KEYWORD_CONST) + || token->is_keyword(KEYWORD_TYPE) + || token->is_keyword(KEYWORD_VAR) + || token->is_keyword(KEYWORD_FUNC)); +} + +// Decl<P> = P | "(" [ List<P> ] ")" . + +void +Parse::decl(void (Parse::*pfn)(void*), void* varg) +{ + if (!this->peek_token()->is_op(OPERATOR_LPAREN)) + (this->*pfn)(varg); + else + { + if (!this->advance_token()->is_op(OPERATOR_RPAREN)) + { + this->list(pfn, varg, true); + if (!this->peek_token()->is_op(OPERATOR_RPAREN)) + { + error_at(this->location(), "missing %<)%>"); + while (!this->advance_token()->is_op(OPERATOR_RPAREN)) + { + if (this->peek_token()->is_eof()) + return; + } + } + } + this->advance_token(); + } +} + +// List<P> = P { ";" P } [ ";" ] . + +// In order to pick up the trailing semicolon we need to know what +// might follow. This is either a '}' or a ')'. + +void +Parse::list(void (Parse::*pfn)(void*), void* varg, bool follow_is_paren) +{ + (this->*pfn)(varg); + Operator follow = follow_is_paren ? OPERATOR_RPAREN : OPERATOR_RCURLY; + while (this->peek_token()->is_op(OPERATOR_SEMICOLON) + || this->peek_token()->is_op(OPERATOR_COMMA)) + { + if (this->peek_token()->is_op(OPERATOR_COMMA)) + error_at(this->location(), "unexpected comma"); + if (this->advance_token()->is_op(follow)) + break; + (this->*pfn)(varg); + } +} + +// ConstDecl = "const" ( ConstSpec | "(" { ConstSpec ";" } ")" ) . + +void +Parse::const_decl() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_CONST)); + this->advance_token(); + this->reset_iota(); + + Type* last_type = NULL; + Expression_list* last_expr_list = NULL; + + if (!this->peek_token()->is_op(OPERATOR_LPAREN)) + this->const_spec(&last_type, &last_expr_list); + else + { + this->advance_token(); + while (!this->peek_token()->is_op(OPERATOR_RPAREN)) + { + this->const_spec(&last_type, &last_expr_list); + if (this->peek_token()->is_op(OPERATOR_SEMICOLON)) + this->advance_token(); + else if (!this->peek_token()->is_op(OPERATOR_RPAREN)) + { + error_at(this->location(), "expected %<;%> or %<)%> or newline"); + if (!this->skip_past_error(OPERATOR_RPAREN)) + return; + } + } + this->advance_token(); + } + + if (last_expr_list != NULL) + delete last_expr_list; +} + +// ConstSpec = IdentifierList [ [ CompleteType ] "=" ExpressionList ] . + +void +Parse::const_spec(Type** last_type, Expression_list** last_expr_list) +{ + Typed_identifier_list til; + this->identifier_list(&til); + + Type* type = NULL; + if (this->type_may_start_here()) + { + type = this->type(); + *last_type = NULL; + *last_expr_list = NULL; + } + + Expression_list *expr_list; + if (!this->peek_token()->is_op(OPERATOR_EQ)) + { + if (*last_expr_list == NULL) + { + error_at(this->location(), "expected %<=%>"); + return; + } + type = *last_type; + expr_list = new Expression_list; + for (Expression_list::const_iterator p = (*last_expr_list)->begin(); + p != (*last_expr_list)->end(); + ++p) + expr_list->push_back((*p)->copy()); + } + else + { + this->advance_token(); + expr_list = this->expression_list(NULL, false); + *last_type = type; + if (*last_expr_list != NULL) + delete *last_expr_list; + *last_expr_list = expr_list; + } + + Expression_list::const_iterator pe = expr_list->begin(); + for (Typed_identifier_list::iterator pi = til.begin(); + pi != til.end(); + ++pi, ++pe) + { + if (pe == expr_list->end()) + { + error_at(this->location(), "not enough initializers"); + return; + } + if (type != NULL) + pi->set_type(type); + + if (!Gogo::is_sink_name(pi->name())) + this->gogo_->add_constant(*pi, *pe, this->iota_value()); + } + if (pe != expr_list->end()) + error_at(this->location(), "too many initializers"); + + this->increment_iota(); + + return; +} + +// TypeDecl = "type" Decl<TypeSpec> . + +void +Parse::type_decl() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_TYPE)); + this->advance_token(); + this->decl(&Parse::type_spec, NULL); +} + +// TypeSpec = identifier Type . + +void +Parse::type_spec(void*) +{ + const Token* token = this->peek_token(); + if (!token->is_identifier()) + { + error_at(this->location(), "expected identifier"); + return; + } + std::string name = token->identifier(); + bool is_exported = token->is_identifier_exported(); + source_location location = token->location(); + token = this->advance_token(); + + // The scope of the type name starts at the point where the + // identifier appears in the source code. We implement this by + // declaring the type before we read the type definition. + Named_object* named_type = NULL; + if (name != "_") + { + name = this->gogo_->pack_hidden_name(name, is_exported); + named_type = this->gogo_->declare_type(name, location); + } + + Type* type; + if (!this->peek_token()->is_op(OPERATOR_SEMICOLON)) + type = this->type(); + else + { + error_at(this->location(), + "unexpected semicolon or newline in type declaration"); + type = Type::make_error_type(); + this->advance_token(); + } + + if (type->is_error_type()) + { + while (!this->peek_token()->is_op(OPERATOR_SEMICOLON) + && !this->peek_token()->is_eof()) + this->advance_token(); + } + + if (name != "_") + { + if (named_type->is_type_declaration()) + { + Type* ftype = type->forwarded(); + if (ftype->forward_declaration_type() != NULL + && (ftype->forward_declaration_type()->named_object() + == named_type)) + { + error_at(location, "invalid recursive type"); + type = Type::make_error_type(); + } + + this->gogo_->define_type(named_type, + Type::make_named_type(named_type, type, + location)); + gcc_assert(named_type->package() == NULL); + } + else + { + // This will probably give a redefinition error. + this->gogo_->add_type(name, type, location); + } + } +} + +// VarDecl = "var" Decl<VarSpec> . + +void +Parse::var_decl() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_VAR)); + this->advance_token(); + this->decl(&Parse::var_spec, NULL); +} + +// VarSpec = IdentifierList +// ( CompleteType [ "=" ExpressionList ] | "=" ExpressionList ) . + +void +Parse::var_spec(void*) +{ + // Get the variable names. + Typed_identifier_list til; + this->identifier_list(&til); + + source_location location = this->location(); + + Type* type = NULL; + Expression_list* init = NULL; + if (!this->peek_token()->is_op(OPERATOR_EQ)) + { + type = this->type(); + if (type->is_error_type()) + { + while (!this->peek_token()->is_op(OPERATOR_EQ) + && !this->peek_token()->is_op(OPERATOR_SEMICOLON) + && !this->peek_token()->is_eof()) + this->advance_token(); + } + if (this->peek_token()->is_op(OPERATOR_EQ)) + { + this->advance_token(); + init = this->expression_list(NULL, false); + } + } + else + { + this->advance_token(); + init = this->expression_list(NULL, false); + } + + this->init_vars(&til, type, init, false, location); + + if (init != NULL) + delete init; +} + +// Create variables. TIL is a list of variable names. If TYPE is not +// NULL, it is the type of all the variables. If INIT is not NULL, it +// is an initializer list for the variables. + +void +Parse::init_vars(const Typed_identifier_list* til, Type* type, + Expression_list* init, bool is_coloneq, + source_location location) +{ + // Check for an initialization which can yield multiple values. + if (init != NULL && init->size() == 1 && til->size() > 1) + { + if (this->init_vars_from_call(til, type, *init->begin(), is_coloneq, + location)) + return; + if (this->init_vars_from_map(til, type, *init->begin(), is_coloneq, + location)) + return; + if (this->init_vars_from_receive(til, type, *init->begin(), is_coloneq, + location)) + return; + if (this->init_vars_from_type_guard(til, type, *init->begin(), + is_coloneq, location)) + return; + } + + if (init != NULL && init->size() != til->size()) + { + if (init->empty() || !init->front()->is_error_expression()) + error_at(location, "wrong number of initializations"); + init = NULL; + if (type == NULL) + type = Type::make_error_type(); + } + + // Note that INIT was already parsed with the old name bindings, so + // we don't have to worry that it will accidentally refer to the + // newly declared variables. + + Expression_list::const_iterator pexpr; + if (init != NULL) + pexpr = init->begin(); + bool any_new = false; + for (Typed_identifier_list::const_iterator p = til->begin(); + p != til->end(); + ++p) + { + if (init != NULL) + gcc_assert(pexpr != init->end()); + this->init_var(*p, type, init == NULL ? NULL : *pexpr, is_coloneq, + false, &any_new); + if (init != NULL) + ++pexpr; + } + if (init != NULL) + gcc_assert(pexpr == init->end()); + if (is_coloneq && !any_new) + error_at(location, "variables redeclared but no variable is new"); +} + +// See if we need to initialize a list of variables from a function +// call. This returns true if we have set up the variables and the +// initialization. + +bool +Parse::init_vars_from_call(const Typed_identifier_list* vars, Type* type, + Expression* expr, bool is_coloneq, + source_location location) +{ + Call_expression* call = expr->call_expression(); + if (call == NULL) + return false; + + // This is a function call. We can't check here whether it returns + // the right number of values, but it might. Declare the variables, + // and then assign the results of the call to them. + + unsigned int index = 0; + bool any_new = false; + for (Typed_identifier_list::const_iterator pv = vars->begin(); + pv != vars->end(); + ++pv, ++index) + { + Expression* init = Expression::make_call_result(call, index); + this->init_var(*pv, type, init, is_coloneq, false, &any_new); + } + + if (is_coloneq && !any_new) + error_at(location, "variables redeclared but no variable is new"); + + return true; +} + +// See if we need to initialize a pair of values from a map index +// expression. This returns true if we have set up the variables and +// the initialization. + +bool +Parse::init_vars_from_map(const Typed_identifier_list* vars, Type* type, + Expression* expr, bool is_coloneq, + source_location location) +{ + Index_expression* index = expr->index_expression(); + if (index == NULL) + return false; + if (vars->size() != 2) + return false; + + // This is an index which is being assigned to two variables. It + // must be a map index. Declare the variables, and then assign the + // results of the map index. + bool any_new = false; + Typed_identifier_list::const_iterator p = vars->begin(); + Expression* init = type == NULL ? index : NULL; + Named_object* val_no = this->init_var(*p, type, init, is_coloneq, + type == NULL, &any_new); + if (type == NULL && any_new && val_no->is_variable()) + val_no->var_value()->set_type_from_init_tuple(); + Expression* val_var = Expression::make_var_reference(val_no, location); + + ++p; + Type* var_type = type; + if (var_type == NULL) + var_type = Type::lookup_bool_type(); + Named_object* no = this->init_var(*p, var_type, NULL, is_coloneq, false, + &any_new); + Expression* present_var = Expression::make_var_reference(no, location); + + if (is_coloneq && !any_new) + error_at(location, "variables redeclared but no variable is new"); + + Statement* s = Statement::make_tuple_map_assignment(val_var, present_var, + index, location); + + if (!this->gogo_->in_global_scope()) + this->gogo_->add_statement(s); + else if (!val_no->is_sink()) + { + if (val_no->is_variable()) + val_no->var_value()->add_preinit_statement(this->gogo_, s); + } + else if (!no->is_sink()) + { + if (no->is_variable()) + no->var_value()->add_preinit_statement(this->gogo_, s); + } + else + { + // Execute the map index expression just so that we can fail if + // the map is nil. + Named_object* dummy = this->create_dummy_global(Type::lookup_bool_type(), + NULL, location); + dummy->var_value()->add_preinit_statement(this->gogo_, s); + } + + return true; +} + +// See if we need to initialize a pair of values from a receive +// expression. This returns true if we have set up the variables and +// the initialization. + +bool +Parse::init_vars_from_receive(const Typed_identifier_list* vars, Type* type, + Expression* expr, bool is_coloneq, + source_location location) +{ + Receive_expression* receive = expr->receive_expression(); + if (receive == NULL) + return false; + if (vars->size() != 2) + return false; + + // This is a receive expression which is being assigned to two + // variables. Declare the variables, and then assign the results of + // the receive. + bool any_new = false; + Typed_identifier_list::const_iterator p = vars->begin(); + Expression* init = type == NULL ? receive : NULL; + Named_object* val_no = this->init_var(*p, type, init, is_coloneq, + type == NULL, &any_new); + if (type == NULL && any_new && val_no->is_variable()) + val_no->var_value()->set_type_from_init_tuple(); + Expression* val_var = Expression::make_var_reference(val_no, location); + + ++p; + Type* var_type = type; + if (var_type == NULL) + var_type = Type::lookup_bool_type(); + Named_object* no = this->init_var(*p, var_type, NULL, is_coloneq, false, + &any_new); + Expression* received_var = Expression::make_var_reference(no, location); + + if (is_coloneq && !any_new) + error_at(location, "variables redeclared but no variable is new"); + + Statement* s = Statement::make_tuple_receive_assignment(val_var, + received_var, + receive->channel(), + location); + + if (!this->gogo_->in_global_scope()) + this->gogo_->add_statement(s); + else if (!val_no->is_sink()) + { + if (val_no->is_variable()) + val_no->var_value()->add_preinit_statement(this->gogo_, s); + } + else if (!no->is_sink()) + { + if (no->is_variable()) + no->var_value()->add_preinit_statement(this->gogo_, s); + } + else + { + Named_object* dummy = this->create_dummy_global(Type::lookup_bool_type(), + NULL, location); + dummy->var_value()->add_preinit_statement(this->gogo_, s); + } + + return true; +} + +// See if we need to initialize a pair of values from a type guard +// expression. This returns true if we have set up the variables and +// the initialization. + +bool +Parse::init_vars_from_type_guard(const Typed_identifier_list* vars, + Type* type, Expression* expr, + bool is_coloneq, source_location location) +{ + Type_guard_expression* type_guard = expr->type_guard_expression(); + if (type_guard == NULL) + return false; + if (vars->size() != 2) + return false; + + // This is a type guard expression which is being assigned to two + // variables. Declare the variables, and then assign the results of + // the type guard. + bool any_new = false; + Typed_identifier_list::const_iterator p = vars->begin(); + Type* var_type = type; + if (var_type == NULL) + var_type = type_guard->type(); + Named_object* val_no = this->init_var(*p, var_type, NULL, is_coloneq, false, + &any_new); + Expression* val_var = Expression::make_var_reference(val_no, location); + + ++p; + var_type = type; + if (var_type == NULL) + var_type = Type::lookup_bool_type(); + Named_object* no = this->init_var(*p, var_type, NULL, is_coloneq, false, + &any_new); + Expression* ok_var = Expression::make_var_reference(no, location); + + Expression* texpr = type_guard->expr(); + Type* t = type_guard->type(); + Statement* s = Statement::make_tuple_type_guard_assignment(val_var, ok_var, + texpr, t, + location); + + if (is_coloneq && !any_new) + error_at(location, "variables redeclared but no variable is new"); + + if (!this->gogo_->in_global_scope()) + this->gogo_->add_statement(s); + else if (!val_no->is_sink()) + { + if (val_no->is_variable()) + val_no->var_value()->add_preinit_statement(this->gogo_, s); + } + else if (!no->is_sink()) + { + if (no->is_variable()) + no->var_value()->add_preinit_statement(this->gogo_, s); + } + else + { + Named_object* dummy = this->create_dummy_global(type, NULL, location); + dummy->var_value()->add_preinit_statement(this->gogo_, s); + } + + return true; +} + +// Create a single variable. If IS_COLONEQ is true, we permit +// redeclarations in the same block, and we set *IS_NEW when we find a +// new variable which is not a redeclaration. + +Named_object* +Parse::init_var(const Typed_identifier& tid, Type* type, Expression* init, + bool is_coloneq, bool type_from_init, bool* is_new) +{ + source_location location = tid.location(); + + if (Gogo::is_sink_name(tid.name())) + { + if (!type_from_init && init != NULL) + { + if (!this->gogo_->in_global_scope()) + this->gogo_->add_statement(Statement::make_statement(init)); + else + return this->create_dummy_global(type, init, location); + } + return this->gogo_->add_sink(); + } + + if (is_coloneq) + { + Named_object* no = this->gogo_->lookup_in_block(tid.name()); + if (no != NULL + && (no->is_variable() || no->is_result_variable())) + { + // INIT may be NULL even when IS_COLONEQ is true for cases + // like v, ok := x.(int). + if (!type_from_init && init != NULL) + { + Expression *v = Expression::make_var_reference(no, location); + Statement *s = Statement::make_assignment(v, init, location); + this->gogo_->add_statement(s); + } + return no; + } + } + *is_new = true; + Variable* var = new Variable(type, init, this->gogo_->in_global_scope(), + false, false, location); + Named_object* no = this->gogo_->add_variable(tid.name(), var); + if (!no->is_variable()) + { + // The name is already defined, so we just gave an error. + return this->gogo_->add_sink(); + } + return no; +} + +// Create a dummy global variable to force an initializer to be run in +// the right place. This is used when a sink variable is initialized +// at global scope. + +Named_object* +Parse::create_dummy_global(Type* type, Expression* init, + source_location location) +{ + if (type == NULL && init == NULL) + type = Type::lookup_bool_type(); + Variable* var = new Variable(type, init, true, false, false, location); + static int count; + char buf[30]; + snprintf(buf, sizeof buf, "_.%d", count); + ++count; + return this->gogo_->add_variable(buf, var); +} + +// SimpleVarDecl = identifier ":=" Expression . + +// We've already seen the identifier. + +// FIXME: We also have to implement +// IdentifierList ":=" ExpressionList +// In order to support both "a, b := 1, 0" and "a, b = 1, 0" we accept +// tuple assignments here as well. + +// If P_RANGE_CLAUSE is not NULL, then this will recognize a +// RangeClause. + +// If P_TYPE_SWITCH is not NULL, this will recognize a type switch +// guard (var := expr.("type") using the literal keyword "type"). + +void +Parse::simple_var_decl_or_assignment(const std::string& name, + source_location location, + Range_clause* p_range_clause, + Type_switch* p_type_switch) +{ + Typed_identifier_list til; + til.push_back(Typed_identifier(name, NULL, location)); + + // We've seen one identifier. If we see a comma now, this could be + // "a, *p = 1, 2". + if (this->peek_token()->is_op(OPERATOR_COMMA)) + { + gcc_assert(p_type_switch == NULL); + while (true) + { + const Token* token = this->advance_token(); + if (!token->is_identifier()) + break; + + std::string id = token->identifier(); + bool is_id_exported = token->is_identifier_exported(); + source_location id_location = token->location(); + + token = this->advance_token(); + if (!token->is_op(OPERATOR_COMMA)) + { + if (token->is_op(OPERATOR_COLONEQ)) + { + id = this->gogo_->pack_hidden_name(id, is_id_exported); + til.push_back(Typed_identifier(id, NULL, location)); + } + else + this->unget_token(Token::make_identifier_token(id, + is_id_exported, + id_location)); + break; + } + + id = this->gogo_->pack_hidden_name(id, is_id_exported); + til.push_back(Typed_identifier(id, NULL, location)); + } + + // We have a comma separated list of identifiers in TIL. If the + // next token is COLONEQ, then this is a simple var decl, and we + // have the complete list of identifiers. If the next token is + // not COLONEQ, then the only valid parse is a tuple assignment. + // The list of identifiers we have so far is really a list of + // expressions. There are more expressions following. + + if (!this->peek_token()->is_op(OPERATOR_COLONEQ)) + { + Expression_list* exprs = new Expression_list; + for (Typed_identifier_list::const_iterator p = til.begin(); + p != til.end(); + ++p) + exprs->push_back(this->id_to_expression(p->name(), + p->location())); + + Expression_list* more_exprs = this->expression_list(NULL, true); + for (Expression_list::const_iterator p = more_exprs->begin(); + p != more_exprs->end(); + ++p) + exprs->push_back(*p); + delete more_exprs; + + this->tuple_assignment(exprs, p_range_clause); + return; + } + } + + gcc_assert(this->peek_token()->is_op(OPERATOR_COLONEQ)); + const Token* token = this->advance_token(); + + if (p_range_clause != NULL && token->is_keyword(KEYWORD_RANGE)) + { + this->range_clause_decl(&til, p_range_clause); + return; + } + + Expression_list* init; + if (p_type_switch == NULL) + init = this->expression_list(NULL, false); + else + { + bool is_type_switch = false; + Expression* expr = this->expression(PRECEDENCE_NORMAL, false, true, + &is_type_switch); + if (is_type_switch) + { + p_type_switch->found = true; + p_type_switch->name = name; + p_type_switch->location = location; + p_type_switch->expr = expr; + return; + } + + if (!this->peek_token()->is_op(OPERATOR_COMMA)) + { + init = new Expression_list(); + init->push_back(expr); + } + else + { + this->advance_token(); + init = this->expression_list(expr, false); + } + } + + this->init_vars(&til, NULL, init, true, location); +} + +// FunctionDecl = "func" identifier Signature [ Block ] . +// MethodDecl = "func" Receiver identifier Signature [ Block ] . + +// gcc extension: +// FunctionDecl = "func" identifier Signature +// __asm__ "(" string_lit ")" . +// This extension means a function whose real name is the identifier +// inside the asm. + +void +Parse::function_decl() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_FUNC)); + source_location location = this->location(); + const Token* token = this->advance_token(); + + Typed_identifier* rec = NULL; + if (token->is_op(OPERATOR_LPAREN)) + { + rec = this->receiver(); + token = this->peek_token(); + } + + if (!token->is_identifier()) + { + error_at(this->location(), "expected function name"); + return; + } + + std::string name = + this->gogo_->pack_hidden_name(token->identifier(), + token->is_identifier_exported()); + + this->advance_token(); + + Function_type* fntype = this->signature(rec, this->location()); + if (fntype == NULL) + return; + + Named_object* named_object = NULL; + + if (this->peek_token()->is_keyword(KEYWORD_ASM)) + { + if (!this->advance_token()->is_op(OPERATOR_LPAREN)) + { + error_at(this->location(), "expected %<(%>"); + return; + } + token = this->advance_token(); + if (!token->is_string()) + { + error_at(this->location(), "expected string"); + return; + } + std::string asm_name = token->string_value(); + if (!this->advance_token()->is_op(OPERATOR_RPAREN)) + { + error_at(this->location(), "expected %<)%>"); + return; + } + this->advance_token(); + if (!Gogo::is_sink_name(name)) + { + named_object = this->gogo_->declare_function(name, fntype, location); + if (named_object->is_function_declaration()) + named_object->func_declaration_value()->set_asm_name(asm_name); + } + } + + // Check for the easy error of a newline before the opening brace. + if (this->peek_token()->is_op(OPERATOR_SEMICOLON)) + { + source_location semi_loc = this->location(); + if (this->advance_token()->is_op(OPERATOR_LCURLY)) + error_at(this->location(), + "unexpected semicolon or newline before %<{%>"); + else + this->unget_token(Token::make_operator_token(OPERATOR_SEMICOLON, + semi_loc)); + } + + if (!this->peek_token()->is_op(OPERATOR_LCURLY)) + { + if (named_object == NULL && !Gogo::is_sink_name(name)) + this->gogo_->declare_function(name, fntype, location); + } + else + { + this->gogo_->start_function(name, fntype, true, location); + source_location end_loc = this->block(); + this->gogo_->finish_function(end_loc); + } +} + +// Receiver = "(" [ identifier ] [ "*" ] BaseTypeName ")" . +// BaseTypeName = identifier . + +Typed_identifier* +Parse::receiver() +{ + gcc_assert(this->peek_token()->is_op(OPERATOR_LPAREN)); + + std::string name; + const Token* token = this->advance_token(); + source_location location = token->location(); + if (!token->is_op(OPERATOR_MULT)) + { + if (!token->is_identifier()) + { + error_at(this->location(), "method has no receiver"); + while (!token->is_eof() && !token->is_op(OPERATOR_RPAREN)) + token = this->advance_token(); + if (!token->is_eof()) + this->advance_token(); + return NULL; + } + name = token->identifier(); + bool is_exported = token->is_identifier_exported(); + token = this->advance_token(); + if (!token->is_op(OPERATOR_DOT) && !token->is_op(OPERATOR_RPAREN)) + { + // An identifier followed by something other than a dot or a + // right parenthesis must be a receiver name followed by a + // type. + name = this->gogo_->pack_hidden_name(name, is_exported); + } + else + { + // This must be a type name. + this->unget_token(Token::make_identifier_token(name, is_exported, + location)); + token = this->peek_token(); + name.clear(); + } + } + + // Here the receiver name is in NAME (it is empty if the receiver is + // unnamed) and TOKEN is the first token in the type. + + bool is_pointer = false; + if (token->is_op(OPERATOR_MULT)) + { + is_pointer = true; + token = this->advance_token(); + } + + if (!token->is_identifier()) + { + error_at(this->location(), "expected receiver name or type"); + int c = token->is_op(OPERATOR_LPAREN) ? 1 : 0; + while (!token->is_eof()) + { + token = this->advance_token(); + if (token->is_op(OPERATOR_LPAREN)) + ++c; + else if (token->is_op(OPERATOR_RPAREN)) + { + if (c == 0) + break; + --c; + } + } + if (!token->is_eof()) + this->advance_token(); + return NULL; + } + + Type* type = this->type_name(true); + + if (is_pointer && !type->is_error_type()) + type = Type::make_pointer_type(type); + + if (this->peek_token()->is_op(OPERATOR_RPAREN)) + this->advance_token(); + else + { + if (this->peek_token()->is_op(OPERATOR_COMMA)) + error_at(this->location(), "method has multiple receivers"); + else + error_at(this->location(), "expected %<)%>"); + while (!token->is_eof() && !token->is_op(OPERATOR_RPAREN)) + token = this->advance_token(); + if (!token->is_eof()) + this->advance_token(); + return NULL; + } + + return new Typed_identifier(name, type, location); +} + +// Operand = Literal | QualifiedIdent | MethodExpr | "(" Expression ")" . +// Literal = BasicLit | CompositeLit | FunctionLit . +// BasicLit = int_lit | float_lit | imaginary_lit | char_lit | string_lit . + +// If MAY_BE_SINK is true, this operand may be "_". + +Expression* +Parse::operand(bool may_be_sink) +{ + const Token* token = this->peek_token(); + Expression* ret; + switch (token->classification()) + { + case Token::TOKEN_IDENTIFIER: + { + source_location location = token->location(); + std::string id = token->identifier(); + bool is_exported = token->is_identifier_exported(); + std::string packed = this->gogo_->pack_hidden_name(id, is_exported); + + Named_object* in_function; + Named_object* named_object = this->gogo_->lookup(packed, &in_function); + + Package* package = NULL; + if (named_object != NULL && named_object->is_package()) + { + if (!this->advance_token()->is_op(OPERATOR_DOT) + || !this->advance_token()->is_identifier()) + { + error_at(location, "unexpected reference to package"); + return Expression::make_error(location); + } + package = named_object->package_value(); + package->set_used(); + id = this->peek_token()->identifier(); + is_exported = this->peek_token()->is_identifier_exported(); + packed = this->gogo_->pack_hidden_name(id, is_exported); + named_object = package->lookup(packed); + location = this->location(); + gcc_assert(in_function == NULL); + } + + this->advance_token(); + + if (named_object != NULL + && named_object->is_type() + && !named_object->type_value()->is_visible()) + { + gcc_assert(package != NULL); + error_at(location, "invalid reference to hidden type %<%s.%s%>", + Gogo::message_name(package->name()).c_str(), + Gogo::message_name(id).c_str()); + return Expression::make_error(location); + } + + + if (named_object == NULL) + { + if (package != NULL) + { + std::string n1 = Gogo::message_name(package->name()); + std::string n2 = Gogo::message_name(id); + if (!is_exported) + error_at(location, + ("invalid reference to unexported identifier " + "%<%s.%s%>"), + n1.c_str(), n2.c_str()); + else + error_at(location, + "reference to undefined identifier %<%s.%s%>", + n1.c_str(), n2.c_str()); + return Expression::make_error(location); + } + + named_object = this->gogo_->add_unknown_name(packed, location); + } + + if (in_function != NULL + && in_function != this->gogo_->current_function() + && (named_object->is_variable() + || named_object->is_result_variable())) + return this->enclosing_var_reference(in_function, named_object, + location); + + switch (named_object->classification()) + { + case Named_object::NAMED_OBJECT_CONST: + return Expression::make_const_reference(named_object, location); + case Named_object::NAMED_OBJECT_TYPE: + return Expression::make_type(named_object->type_value(), location); + case Named_object::NAMED_OBJECT_TYPE_DECLARATION: + { + Type* t = Type::make_forward_declaration(named_object); + return Expression::make_type(t, location); + } + case Named_object::NAMED_OBJECT_VAR: + case Named_object::NAMED_OBJECT_RESULT_VAR: + return Expression::make_var_reference(named_object, location); + case Named_object::NAMED_OBJECT_SINK: + if (may_be_sink) + return Expression::make_sink(location); + else + { + error_at(location, "cannot use _ as value"); + return Expression::make_error(location); + } + case Named_object::NAMED_OBJECT_FUNC: + case Named_object::NAMED_OBJECT_FUNC_DECLARATION: + return Expression::make_func_reference(named_object, NULL, + location); + case Named_object::NAMED_OBJECT_UNKNOWN: + return Expression::make_unknown_reference(named_object, location); + default: + gcc_unreachable(); + } + } + gcc_unreachable(); + + case Token::TOKEN_STRING: + ret = Expression::make_string(token->string_value(), token->location()); + this->advance_token(); + return ret; + + case Token::TOKEN_INTEGER: + ret = Expression::make_integer(token->integer_value(), NULL, + token->location()); + this->advance_token(); + return ret; + + case Token::TOKEN_FLOAT: + ret = Expression::make_float(token->float_value(), NULL, + token->location()); + this->advance_token(); + return ret; + + case Token::TOKEN_IMAGINARY: + { + mpfr_t zero; + mpfr_init_set_ui(zero, 0, GMP_RNDN); + ret = Expression::make_complex(&zero, token->imaginary_value(), + NULL, token->location()); + mpfr_clear(zero); + this->advance_token(); + return ret; + } + + case Token::TOKEN_KEYWORD: + switch (token->keyword()) + { + case KEYWORD_FUNC: + return this->function_lit(); + case KEYWORD_CHAN: + case KEYWORD_INTERFACE: + case KEYWORD_MAP: + case KEYWORD_STRUCT: + { + source_location location = token->location(); + return Expression::make_type(this->type(), location); + } + default: + break; + } + break; + + case Token::TOKEN_OPERATOR: + if (token->is_op(OPERATOR_LPAREN)) + { + this->advance_token(); + ret = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + if (!this->peek_token()->is_op(OPERATOR_RPAREN)) + error_at(this->location(), "missing %<)%>"); + else + this->advance_token(); + return ret; + } + else if (token->is_op(OPERATOR_LSQUARE)) + { + // Here we call array_type directly, as this is the only + // case where an ellipsis is permitted for an array type. + source_location location = token->location(); + return Expression::make_type(this->array_type(true), location); + } + break; + + default: + break; + } + + error_at(this->location(), "expected operand"); + return Expression::make_error(this->location()); +} + +// Handle a reference to a variable in an enclosing function. We add +// it to a list of such variables. We return a reference to a field +// in a struct which will be passed on the static chain when calling +// the current function. + +Expression* +Parse::enclosing_var_reference(Named_object* in_function, Named_object* var, + source_location location) +{ + gcc_assert(var->is_variable() || var->is_result_variable()); + + Named_object* this_function = this->gogo_->current_function(); + Named_object* closure = this_function->func_value()->closure_var(); + + Enclosing_var ev(var, in_function, this->enclosing_vars_.size()); + std::pair<Enclosing_vars::iterator, bool> ins = + this->enclosing_vars_.insert(ev); + if (ins.second) + { + // This is a variable we have not seen before. Add a new field + // to the closure type. + this_function->func_value()->add_closure_field(var, location); + } + + Expression* closure_ref = Expression::make_var_reference(closure, + location); + closure_ref = Expression::make_unary(OPERATOR_MULT, closure_ref, location); + + // The closure structure holds pointers to the variables, so we need + // to introduce an indirection. + Expression* e = Expression::make_field_reference(closure_ref, + ins.first->index(), + location); + e = Expression::make_unary(OPERATOR_MULT, e, location); + return e; +} + +// CompositeLit = LiteralType LiteralValue . +// LiteralType = StructType | ArrayType | "[" "..." "]" ElementType | +// SliceType | MapType | TypeName . +// LiteralValue = "{" [ ElementList [ "," ] ] "}" . +// ElementList = Element { "," Element } . +// Element = [ Key ":" ] Value . +// Key = Expression . +// Value = Expression | LiteralValue . + +// We have already seen the type if there is one, and we are now +// looking at the LiteralValue. The case "[" "..." "]" ElementType +// will be seen here as an array type whose length is "nil". The +// DEPTH parameter is non-zero if this is an embedded composite +// literal and the type was omitted. It gives the number of steps up +// to the type which was provided. E.g., in [][]int{{1}} it will be +// 1. In [][][]int{{{1}}} it will be 2. + +Expression* +Parse::composite_lit(Type* type, int depth, source_location location) +{ + gcc_assert(this->peek_token()->is_op(OPERATOR_LCURLY)); + this->advance_token(); + + if (this->peek_token()->is_op(OPERATOR_RCURLY)) + { + this->advance_token(); + return Expression::make_composite_literal(type, depth, false, NULL, + location); + } + + bool has_keys = false; + Expression_list* vals = new Expression_list; + while (true) + { + Expression* val; + bool is_type_omitted = false; + + const Token* token = this->peek_token(); + + if (!token->is_op(OPERATOR_LCURLY)) + val = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + else + { + // This must be a composite literal inside another composite + // literal, with the type omitted for the inner one. + val = this->composite_lit(type, depth + 1, token->location()); + is_type_omitted = true; + } + + token = this->peek_token(); + if (!token->is_op(OPERATOR_COLON)) + { + if (has_keys) + vals->push_back(NULL); + } + else + { + if (is_type_omitted && !val->is_error_expression()) + { + error_at(this->location(), "unexpected %<:%>"); + val = Expression::make_error(this->location()); + } + + this->advance_token(); + + if (!has_keys && !vals->empty()) + { + Expression_list* newvals = new Expression_list; + for (Expression_list::const_iterator p = vals->begin(); + p != vals->end(); + ++p) + { + newvals->push_back(NULL); + newvals->push_back(*p); + } + delete vals; + vals = newvals; + } + has_keys = true; + + if (val->unknown_expression() != NULL) + val->unknown_expression()->set_is_composite_literal_key(); + + vals->push_back(val); + + if (!token->is_op(OPERATOR_LCURLY)) + val = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + else + { + // This must be a composite literal inside another + // composite literal, with the type omitted for the + // inner one. + val = this->composite_lit(type, depth + 1, token->location()); + } + + token = this->peek_token(); + } + + vals->push_back(val); + + if (token->is_op(OPERATOR_COMMA)) + { + if (this->advance_token()->is_op(OPERATOR_RCURLY)) + { + this->advance_token(); + break; + } + } + else if (token->is_op(OPERATOR_RCURLY)) + { + this->advance_token(); + break; + } + else + { + error_at(this->location(), "expected %<,%> or %<}%>"); + + int depth = 0; + while (!token->is_eof() + && (depth > 0 || !token->is_op(OPERATOR_RCURLY))) + { + if (token->is_op(OPERATOR_LCURLY)) + ++depth; + else if (token->is_op(OPERATOR_RCURLY)) + --depth; + token = this->advance_token(); + } + if (token->is_op(OPERATOR_RCURLY)) + this->advance_token(); + + return Expression::make_error(location); + } + } + + return Expression::make_composite_literal(type, depth, has_keys, vals, + location); +} + +// FunctionLit = "func" Signature Block . + +Expression* +Parse::function_lit() +{ + source_location location = this->location(); + gcc_assert(this->peek_token()->is_keyword(KEYWORD_FUNC)); + this->advance_token(); + + Enclosing_vars hold_enclosing_vars; + hold_enclosing_vars.swap(this->enclosing_vars_); + + Function_type* type = this->signature(NULL, location); + if (type == NULL) + type = Type::make_function_type(NULL, NULL, NULL, location); + + // For a function literal, the next token must be a '{'. If we + // don't see that, then we may have a type expression. + if (!this->peek_token()->is_op(OPERATOR_LCURLY)) + return Expression::make_type(type, location); + + Bc_stack* hold_break_stack = this->break_stack_; + Bc_stack* hold_continue_stack = this->continue_stack_; + this->break_stack_ = NULL; + this->continue_stack_ = NULL; + + Named_object* no = this->gogo_->start_function("", type, true, location); + + source_location end_loc = this->block(); + + this->gogo_->finish_function(end_loc); + + if (this->break_stack_ != NULL) + delete this->break_stack_; + if (this->continue_stack_ != NULL) + delete this->continue_stack_; + this->break_stack_ = hold_break_stack; + this->continue_stack_ = hold_continue_stack; + + hold_enclosing_vars.swap(this->enclosing_vars_); + + Expression* closure = this->create_closure(no, &hold_enclosing_vars, + location); + + return Expression::make_func_reference(no, closure, location); +} + +// Create a closure for the nested function FUNCTION. This is based +// on ENCLOSING_VARS, which is a list of all variables defined in +// enclosing functions and referenced from FUNCTION. A closure is the +// address of a struct which contains the addresses of all the +// referenced variables. This returns NULL if no closure is required. + +Expression* +Parse::create_closure(Named_object* function, Enclosing_vars* enclosing_vars, + source_location location) +{ + if (enclosing_vars->empty()) + return NULL; + + // Get the variables in order by their field index. + + size_t enclosing_var_count = enclosing_vars->size(); + std::vector<Enclosing_var> ev(enclosing_var_count); + for (Enclosing_vars::const_iterator p = enclosing_vars->begin(); + p != enclosing_vars->end(); + ++p) + ev[p->index()] = *p; + + // Build an initializer for a composite literal of the closure's + // type. + + Named_object* enclosing_function = this->gogo_->current_function(); + Expression_list* initializer = new Expression_list; + for (size_t i = 0; i < enclosing_var_count; ++i) + { + gcc_assert(ev[i].index() == i); + Named_object* var = ev[i].var(); + Expression* ref; + if (ev[i].in_function() == enclosing_function) + ref = Expression::make_var_reference(var, location); + else + ref = this->enclosing_var_reference(ev[i].in_function(), var, + location); + Expression* refaddr = Expression::make_unary(OPERATOR_AND, ref, + location); + initializer->push_back(refaddr); + } + + Named_object* closure_var = function->func_value()->closure_var(); + Struct_type* st = closure_var->var_value()->type()->deref()->struct_type(); + Expression* cv = Expression::make_struct_composite_literal(st, initializer, + location); + return Expression::make_heap_composite(cv, location); +} + +// PrimaryExpr = Operand { Selector | Index | Slice | TypeGuard | Call } . + +// If MAY_BE_SINK is true, this expression may be "_". + +// If MAY_BE_COMPOSITE_LIT is true, this expression may be a composite +// literal. + +// If IS_TYPE_SWITCH is not NULL, this will recognize a type switch +// guard (var := expr.("type") using the literal keyword "type"). + +Expression* +Parse::primary_expr(bool may_be_sink, bool may_be_composite_lit, + bool* is_type_switch) +{ + source_location start_loc = this->location(); + bool is_parenthesized = this->peek_token()->is_op(OPERATOR_LPAREN); + + Expression* ret = this->operand(may_be_sink); + + // An unknown name followed by a curly brace must be a composite + // literal, and the unknown name must be a type. + if (may_be_composite_lit + && !is_parenthesized + && ret->unknown_expression() != NULL + && this->peek_token()->is_op(OPERATOR_LCURLY)) + { + Named_object* no = ret->unknown_expression()->named_object(); + Type* type = Type::make_forward_declaration(no); + ret = Expression::make_type(type, ret->location()); + } + + // We handle composite literals and type casts here, as it is the + // easiest way to handle types which are in parentheses, as in + // "((uint))(1)". + if (ret->is_type_expression()) + { + if (this->peek_token()->is_op(OPERATOR_LCURLY)) + { + if (is_parenthesized) + error_at(start_loc, + "cannot parenthesize type in composite literal"); + ret = this->composite_lit(ret->type(), 0, ret->location()); + } + else if (this->peek_token()->is_op(OPERATOR_LPAREN)) + { + source_location loc = this->location(); + this->advance_token(); + Expression* expr = this->expression(PRECEDENCE_NORMAL, false, true, + NULL); + if (!this->peek_token()->is_op(OPERATOR_RPAREN)) + error_at(this->location(), "expected %<)%>"); + else + this->advance_token(); + if (expr->is_error_expression()) + return expr; + ret = Expression::make_cast(ret->type(), expr, loc); + } + } + + while (true) + { + const Token* token = this->peek_token(); + if (token->is_op(OPERATOR_LPAREN)) + ret = this->call(this->verify_not_sink(ret)); + else if (token->is_op(OPERATOR_DOT)) + { + ret = this->selector(this->verify_not_sink(ret), is_type_switch); + if (is_type_switch != NULL && *is_type_switch) + break; + } + else if (token->is_op(OPERATOR_LSQUARE)) + ret = this->index(this->verify_not_sink(ret)); + else + break; + } + + return ret; +} + +// Selector = "." identifier . +// TypeGuard = "." "(" QualifiedIdent ")" . + +// Note that Operand can expand to QualifiedIdent, which contains a +// ".". That is handled directly in operand when it sees a package +// name. + +// If IS_TYPE_SWITCH is not NULL, this will recognize a type switch +// guard (var := expr.("type") using the literal keyword "type"). + +Expression* +Parse::selector(Expression* left, bool* is_type_switch) +{ + gcc_assert(this->peek_token()->is_op(OPERATOR_DOT)); + source_location location = this->location(); + + const Token* token = this->advance_token(); + if (token->is_identifier()) + { + // This could be a field in a struct, or a method in an + // interface, or a method associated with a type. We can't know + // which until we have seen all the types. + std::string name = + this->gogo_->pack_hidden_name(token->identifier(), + token->is_identifier_exported()); + if (token->identifier() == "_") + { + error_at(this->location(), "invalid use of %<_%>"); + name = this->gogo_->pack_hidden_name("blank", false); + } + this->advance_token(); + return Expression::make_selector(left, name, location); + } + else if (token->is_op(OPERATOR_LPAREN)) + { + this->advance_token(); + Type* type = NULL; + if (!this->peek_token()->is_keyword(KEYWORD_TYPE)) + type = this->type(); + else + { + if (is_type_switch != NULL) + *is_type_switch = true; + else + { + error_at(this->location(), + "use of %<.(type)%> outside type switch"); + type = Type::make_error_type(); + } + this->advance_token(); + } + if (!this->peek_token()->is_op(OPERATOR_RPAREN)) + error_at(this->location(), "missing %<)%>"); + else + this->advance_token(); + if (is_type_switch != NULL && *is_type_switch) + return left; + return Expression::make_type_guard(left, type, location); + } + else + { + error_at(this->location(), "expected identifier or %<(%>"); + return left; + } +} + +// Index = "[" Expression "]" . +// Slice = "[" Expression ":" [ Expression ] "]" . + +Expression* +Parse::index(Expression* expr) +{ + source_location location = this->location(); + gcc_assert(this->peek_token()->is_op(OPERATOR_LSQUARE)); + this->advance_token(); + + Expression* start; + if (!this->peek_token()->is_op(OPERATOR_COLON)) + start = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + else + { + mpz_t zero; + mpz_init_set_ui(zero, 0); + start = Expression::make_integer(&zero, NULL, location); + mpz_clear(zero); + } + + Expression* end = NULL; + if (this->peek_token()->is_op(OPERATOR_COLON)) + { + // We use nil to indicate a missing high expression. + if (this->advance_token()->is_op(OPERATOR_RSQUARE)) + end = Expression::make_nil(this->location()); + else + end = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + } + if (!this->peek_token()->is_op(OPERATOR_RSQUARE)) + error_at(this->location(), "missing %<]%>"); + else + this->advance_token(); + return Expression::make_index(expr, start, end, location); +} + +// Call = "(" [ ArgumentList [ "," ] ] ")" . +// ArgumentList = ExpressionList [ "..." ] . + +Expression* +Parse::call(Expression* func) +{ + gcc_assert(this->peek_token()->is_op(OPERATOR_LPAREN)); + Expression_list* args = NULL; + bool is_varargs = false; + const Token* token = this->advance_token(); + if (!token->is_op(OPERATOR_RPAREN)) + { + args = this->expression_list(NULL, false); + token = this->peek_token(); + if (token->is_op(OPERATOR_ELLIPSIS)) + { + is_varargs = true; + token = this->advance_token(); + } + } + if (token->is_op(OPERATOR_COMMA)) + token = this->advance_token(); + if (!token->is_op(OPERATOR_RPAREN)) + error_at(this->location(), "missing %<)%>"); + else + this->advance_token(); + if (func->is_error_expression()) + return func; + return Expression::make_call(func, args, is_varargs, func->location()); +} + +// Return an expression for a single unqualified identifier. + +Expression* +Parse::id_to_expression(const std::string& name, source_location location) +{ + Named_object* in_function; + Named_object* named_object = this->gogo_->lookup(name, &in_function); + if (named_object == NULL) + named_object = this->gogo_->add_unknown_name(name, location); + + if (in_function != NULL + && in_function != this->gogo_->current_function() + && (named_object->is_variable() || named_object->is_result_variable())) + return this->enclosing_var_reference(in_function, named_object, + location); + + switch (named_object->classification()) + { + case Named_object::NAMED_OBJECT_CONST: + return Expression::make_const_reference(named_object, location); + case Named_object::NAMED_OBJECT_VAR: + case Named_object::NAMED_OBJECT_RESULT_VAR: + return Expression::make_var_reference(named_object, location); + case Named_object::NAMED_OBJECT_SINK: + return Expression::make_sink(location); + case Named_object::NAMED_OBJECT_FUNC: + case Named_object::NAMED_OBJECT_FUNC_DECLARATION: + return Expression::make_func_reference(named_object, NULL, location); + case Named_object::NAMED_OBJECT_UNKNOWN: + return Expression::make_unknown_reference(named_object, location); + default: + error_at(this->location(), "unexpected type of identifier"); + return Expression::make_error(location); + } +} + +// Expression = UnaryExpr { binary_op Expression } . + +// PRECEDENCE is the precedence of the current operator. + +// If MAY_BE_SINK is true, this expression may be "_". + +// If MAY_BE_COMPOSITE_LIT is true, this expression may be a composite +// literal. + +// If IS_TYPE_SWITCH is not NULL, this will recognize a type switch +// guard (var := expr.("type") using the literal keyword "type"). + +Expression* +Parse::expression(Precedence precedence, bool may_be_sink, + bool may_be_composite_lit, bool* is_type_switch) +{ + Expression* left = this->unary_expr(may_be_sink, may_be_composite_lit, + is_type_switch); + + while (true) + { + if (is_type_switch != NULL && *is_type_switch) + return left; + + const Token* token = this->peek_token(); + if (token->classification() != Token::TOKEN_OPERATOR) + { + // Not a binary_op. + return left; + } + + Precedence right_precedence; + switch (token->op()) + { + case OPERATOR_OROR: + right_precedence = PRECEDENCE_OROR; + break; + case OPERATOR_ANDAND: + right_precedence = PRECEDENCE_ANDAND; + break; + case OPERATOR_CHANOP: + right_precedence = PRECEDENCE_CHANOP; + break; + case OPERATOR_EQEQ: + case OPERATOR_NOTEQ: + case OPERATOR_LT: + case OPERATOR_LE: + case OPERATOR_GT: + case OPERATOR_GE: + right_precedence = PRECEDENCE_RELOP; + break; + case OPERATOR_PLUS: + case OPERATOR_MINUS: + case OPERATOR_OR: + case OPERATOR_XOR: + right_precedence = PRECEDENCE_ADDOP; + break; + case OPERATOR_MULT: + case OPERATOR_DIV: + case OPERATOR_MOD: + case OPERATOR_LSHIFT: + case OPERATOR_RSHIFT: + case OPERATOR_AND: + case OPERATOR_BITCLEAR: + right_precedence = PRECEDENCE_MULOP; + break; + default: + right_precedence = PRECEDENCE_INVALID; + break; + } + + if (right_precedence == PRECEDENCE_INVALID) + { + // Not a binary_op. + return left; + } + + Operator op = token->op(); + source_location binop_location = token->location(); + + if (precedence >= right_precedence) + { + // We've already seen A * B, and we see + C. We want to + // return so that A * B becomes a group. + return left; + } + + this->advance_token(); + + left = this->verify_not_sink(left); + Expression* right = this->expression(right_precedence, false, + may_be_composite_lit, + NULL); + if (op == OPERATOR_CHANOP) + left = Expression::make_send(left, right, binop_location); + else + left = Expression::make_binary(op, left, right, binop_location); + } +} + +bool +Parse::expression_may_start_here() +{ + const Token* token = this->peek_token(); + switch (token->classification()) + { + case Token::TOKEN_INVALID: + case Token::TOKEN_EOF: + return false; + case Token::TOKEN_KEYWORD: + switch (token->keyword()) + { + case KEYWORD_CHAN: + case KEYWORD_FUNC: + case KEYWORD_MAP: + case KEYWORD_STRUCT: + case KEYWORD_INTERFACE: + return true; + default: + return false; + } + case Token::TOKEN_IDENTIFIER: + return true; + case Token::TOKEN_STRING: + return true; + case Token::TOKEN_OPERATOR: + switch (token->op()) + { + case OPERATOR_PLUS: + case OPERATOR_MINUS: + case OPERATOR_NOT: + case OPERATOR_XOR: + case OPERATOR_MULT: + case OPERATOR_CHANOP: + case OPERATOR_AND: + case OPERATOR_LPAREN: + case OPERATOR_LSQUARE: + return true; + default: + return false; + } + case Token::TOKEN_INTEGER: + case Token::TOKEN_FLOAT: + case Token::TOKEN_IMAGINARY: + return true; + default: + gcc_unreachable(); + } +} + +// UnaryExpr = unary_op UnaryExpr | PrimaryExpr . + +// If MAY_BE_SINK is true, this expression may be "_". + +// If MAY_BE_COMPOSITE_LIT is true, this expression may be a composite +// literal. + +// If IS_TYPE_SWITCH is not NULL, this will recognize a type switch +// guard (var := expr.("type") using the literal keyword "type"). + +Expression* +Parse::unary_expr(bool may_be_sink, bool may_be_composite_lit, + bool* is_type_switch) +{ + const Token* token = this->peek_token(); + if (token->is_op(OPERATOR_PLUS) + || token->is_op(OPERATOR_MINUS) + || token->is_op(OPERATOR_NOT) + || token->is_op(OPERATOR_XOR) + || token->is_op(OPERATOR_CHANOP) + || token->is_op(OPERATOR_MULT) + || token->is_op(OPERATOR_AND)) + { + source_location location = token->location(); + Operator op = token->op(); + this->advance_token(); + + if (op == OPERATOR_CHANOP + && this->peek_token()->is_keyword(KEYWORD_CHAN)) + { + // This is "<- chan" which must be the start of a type. + this->unget_token(Token::make_operator_token(op, location)); + return Expression::make_type(this->type(), location); + } + + Expression* expr = this->unary_expr(false, may_be_composite_lit, NULL); + if (expr->is_error_expression()) + ; + else if (op == OPERATOR_MULT && expr->is_type_expression()) + expr = Expression::make_type(Type::make_pointer_type(expr->type()), + location); + else if (op == OPERATOR_AND && expr->is_composite_literal()) + expr = Expression::make_heap_composite(expr, location); + else if (op != OPERATOR_CHANOP) + expr = Expression::make_unary(op, expr, location); + else + expr = Expression::make_receive(expr, location); + return expr; + } + else + return this->primary_expr(may_be_sink, may_be_composite_lit, + is_type_switch); +} + +// Statement = +// Declaration | LabeledStmt | SimpleStmt | +// GoStmt | ReturnStmt | BreakStmt | ContinueStmt | GotoStmt | +// FallthroughStmt | Block | IfStmt | SwitchStmt | SelectStmt | ForStmt | +// DeferStmt . + +// LABEL is the label of this statement if it has one. + +void +Parse::statement(const Label* label) +{ + const Token* token = this->peek_token(); + switch (token->classification()) + { + case Token::TOKEN_KEYWORD: + { + switch (token->keyword()) + { + case KEYWORD_CONST: + case KEYWORD_TYPE: + case KEYWORD_VAR: + this->declaration(); + break; + case KEYWORD_FUNC: + case KEYWORD_MAP: + case KEYWORD_STRUCT: + case KEYWORD_INTERFACE: + this->simple_stat(true, false, NULL, NULL); + break; + case KEYWORD_GO: + case KEYWORD_DEFER: + this->go_or_defer_stat(); + break; + case KEYWORD_RETURN: + this->return_stat(); + break; + case KEYWORD_BREAK: + this->break_stat(); + break; + case KEYWORD_CONTINUE: + this->continue_stat(); + break; + case KEYWORD_GOTO: + this->goto_stat(); + break; + case KEYWORD_IF: + this->if_stat(); + break; + case KEYWORD_SWITCH: + this->switch_stat(label); + break; + case KEYWORD_SELECT: + this->select_stat(label); + break; + case KEYWORD_FOR: + this->for_stat(label); + break; + default: + error_at(this->location(), "expected statement"); + this->advance_token(); + break; + } + } + break; + + case Token::TOKEN_IDENTIFIER: + { + std::string identifier = token->identifier(); + bool is_exported = token->is_identifier_exported(); + source_location location = token->location(); + if (this->advance_token()->is_op(OPERATOR_COLON)) + { + this->advance_token(); + this->labeled_stmt(identifier, location); + } + else + { + this->unget_token(Token::make_identifier_token(identifier, + is_exported, + location)); + this->simple_stat(true, false, NULL, NULL); + } + } + break; + + case Token::TOKEN_OPERATOR: + if (token->is_op(OPERATOR_LCURLY)) + { + source_location location = token->location(); + this->gogo_->start_block(location); + source_location end_loc = this->block(); + this->gogo_->add_block(this->gogo_->finish_block(end_loc), + location); + } + else if (!token->is_op(OPERATOR_SEMICOLON)) + this->simple_stat(true, false, NULL, NULL); + break; + + case Token::TOKEN_STRING: + case Token::TOKEN_INTEGER: + case Token::TOKEN_FLOAT: + case Token::TOKEN_IMAGINARY: + this->simple_stat(true, false, NULL, NULL); + break; + + default: + error_at(this->location(), "expected statement"); + this->advance_token(); + break; + } +} + +bool +Parse::statement_may_start_here() +{ + const Token* token = this->peek_token(); + switch (token->classification()) + { + case Token::TOKEN_KEYWORD: + { + switch (token->keyword()) + { + case KEYWORD_CONST: + case KEYWORD_TYPE: + case KEYWORD_VAR: + case KEYWORD_FUNC: + case KEYWORD_MAP: + case KEYWORD_STRUCT: + case KEYWORD_INTERFACE: + case KEYWORD_GO: + case KEYWORD_DEFER: + case KEYWORD_RETURN: + case KEYWORD_BREAK: + case KEYWORD_CONTINUE: + case KEYWORD_GOTO: + case KEYWORD_IF: + case KEYWORD_SWITCH: + case KEYWORD_SELECT: + case KEYWORD_FOR: + return true; + + default: + return false; + } + } + break; + + case Token::TOKEN_IDENTIFIER: + return true; + + case Token::TOKEN_OPERATOR: + if (token->is_op(OPERATOR_LCURLY) + || token->is_op(OPERATOR_SEMICOLON)) + return true; + else + return this->expression_may_start_here(); + + case Token::TOKEN_STRING: + case Token::TOKEN_INTEGER: + case Token::TOKEN_FLOAT: + case Token::TOKEN_IMAGINARY: + return true; + + default: + return false; + } +} + +// LabeledStmt = Label ":" Statement . +// Label = identifier . + +void +Parse::labeled_stmt(const std::string& label_name, source_location location) +{ + Label* label = this->gogo_->add_label_definition(label_name, location); + + if (this->peek_token()->is_op(OPERATOR_RCURLY)) + { + // This is a label at the end of a block. A program is + // permitted to omit a semicolon here. + return; + } + + if (!this->statement_may_start_here()) + { + error_at(location, "missing statement after label"); + this->unget_token(Token::make_operator_token(OPERATOR_SEMICOLON, + location)); + return; + } + + this->statement(label); +} + +// SimpleStat = +// ExpressionStat | IncDecStat | Assignment | SimpleVarDecl . + +// In order to make this work for if and switch statements, if +// RETURN_EXP is true, and we see an ExpressionStat, we return the +// expression rather than adding an expression statement to the +// current block. If we see something other than an ExpressionStat, +// we add the statement and return NULL. + +// If P_RANGE_CLAUSE is not NULL, then this will recognize a +// RangeClause. + +// If P_TYPE_SWITCH is not NULL, this will recognize a type switch +// guard (var := expr.("type") using the literal keyword "type"). + +Expression* +Parse::simple_stat(bool may_be_composite_lit, bool return_exp, + Range_clause* p_range_clause, Type_switch* p_type_switch) +{ + const Token* token = this->peek_token(); + + // An identifier follow by := is a SimpleVarDecl. + if (token->is_identifier()) + { + std::string identifier = token->identifier(); + bool is_exported = token->is_identifier_exported(); + source_location location = token->location(); + + token = this->advance_token(); + if (token->is_op(OPERATOR_COLONEQ) + || token->is_op(OPERATOR_COMMA)) + { + identifier = this->gogo_->pack_hidden_name(identifier, is_exported); + this->simple_var_decl_or_assignment(identifier, location, + p_range_clause, + (token->is_op(OPERATOR_COLONEQ) + ? p_type_switch + : NULL)); + return NULL; + } + + this->unget_token(Token::make_identifier_token(identifier, is_exported, + location)); + } + + Expression* exp = this->expression(PRECEDENCE_NORMAL, true, + may_be_composite_lit, + (p_type_switch == NULL + ? NULL + : &p_type_switch->found)); + if (p_type_switch != NULL && p_type_switch->found) + { + p_type_switch->name.clear(); + p_type_switch->location = exp->location(); + p_type_switch->expr = this->verify_not_sink(exp); + return NULL; + } + token = this->peek_token(); + if (token->is_op(OPERATOR_PLUSPLUS) || token->is_op(OPERATOR_MINUSMINUS)) + this->inc_dec_stat(this->verify_not_sink(exp)); + else if (token->is_op(OPERATOR_COMMA) + || token->is_op(OPERATOR_EQ)) + this->assignment(exp, p_range_clause); + else if (token->is_op(OPERATOR_PLUSEQ) + || token->is_op(OPERATOR_MINUSEQ) + || token->is_op(OPERATOR_OREQ) + || token->is_op(OPERATOR_XOREQ) + || token->is_op(OPERATOR_MULTEQ) + || token->is_op(OPERATOR_DIVEQ) + || token->is_op(OPERATOR_MODEQ) + || token->is_op(OPERATOR_LSHIFTEQ) + || token->is_op(OPERATOR_RSHIFTEQ) + || token->is_op(OPERATOR_ANDEQ) + || token->is_op(OPERATOR_BITCLEAREQ)) + this->assignment(this->verify_not_sink(exp), p_range_clause); + else if (return_exp) + return this->verify_not_sink(exp); + else + this->expression_stat(this->verify_not_sink(exp)); + + return NULL; +} + +bool +Parse::simple_stat_may_start_here() +{ + return this->expression_may_start_here(); +} + +// Parse { Statement ";" } which is used in a few places. The list of +// statements may end with a right curly brace, in which case the +// semicolon may be omitted. + +void +Parse::statement_list() +{ + while (this->statement_may_start_here()) + { + this->statement(NULL); + if (this->peek_token()->is_op(OPERATOR_SEMICOLON)) + this->advance_token(); + else if (this->peek_token()->is_op(OPERATOR_RCURLY)) + break; + else + { + if (!this->peek_token()->is_eof() || !saw_errors()) + error_at(this->location(), "expected %<;%> or %<}%> or newline"); + if (!this->skip_past_error(OPERATOR_RCURLY)) + return; + } + } +} + +bool +Parse::statement_list_may_start_here() +{ + return this->statement_may_start_here(); +} + +// ExpressionStat = Expression . + +void +Parse::expression_stat(Expression* exp) +{ + exp->discarding_value(); + this->gogo_->add_statement(Statement::make_statement(exp)); +} + +// IncDecStat = Expression ( "++" | "--" ) . + +void +Parse::inc_dec_stat(Expression* exp) +{ + const Token* token = this->peek_token(); + + // Lvalue maps require special handling. + if (exp->index_expression() != NULL) + exp->index_expression()->set_is_lvalue(); + + if (token->is_op(OPERATOR_PLUSPLUS)) + this->gogo_->add_statement(Statement::make_inc_statement(exp)); + else if (token->is_op(OPERATOR_MINUSMINUS)) + this->gogo_->add_statement(Statement::make_dec_statement(exp)); + else + gcc_unreachable(); + this->advance_token(); +} + +// Assignment = ExpressionList assign_op ExpressionList . + +// EXP is an expression that we have already parsed. + +// If RANGE_CLAUSE is not NULL, then this will recognize a +// RangeClause. + +void +Parse::assignment(Expression* expr, Range_clause* p_range_clause) +{ + Expression_list* vars; + if (!this->peek_token()->is_op(OPERATOR_COMMA)) + { + vars = new Expression_list(); + vars->push_back(expr); + } + else + { + this->advance_token(); + vars = this->expression_list(expr, true); + } + + this->tuple_assignment(vars, p_range_clause); +} + +// An assignment statement. LHS is the list of expressions which +// appear on the left hand side. + +// If RANGE_CLAUSE is not NULL, then this will recognize a +// RangeClause. + +void +Parse::tuple_assignment(Expression_list* lhs, Range_clause* p_range_clause) +{ + const Token* token = this->peek_token(); + if (!token->is_op(OPERATOR_EQ) + && !token->is_op(OPERATOR_PLUSEQ) + && !token->is_op(OPERATOR_MINUSEQ) + && !token->is_op(OPERATOR_OREQ) + && !token->is_op(OPERATOR_XOREQ) + && !token->is_op(OPERATOR_MULTEQ) + && !token->is_op(OPERATOR_DIVEQ) + && !token->is_op(OPERATOR_MODEQ) + && !token->is_op(OPERATOR_LSHIFTEQ) + && !token->is_op(OPERATOR_RSHIFTEQ) + && !token->is_op(OPERATOR_ANDEQ) + && !token->is_op(OPERATOR_BITCLEAREQ)) + { + error_at(this->location(), "expected assignment operator"); + return; + } + Operator op = token->op(); + source_location location = token->location(); + + token = this->advance_token(); + + if (p_range_clause != NULL && token->is_keyword(KEYWORD_RANGE)) + { + if (op != OPERATOR_EQ) + error_at(this->location(), "range clause requires %<=%>"); + this->range_clause_expr(lhs, p_range_clause); + return; + } + + Expression_list* vals = this->expression_list(NULL, false); + + // We've parsed everything; check for errors. + if (lhs == NULL || vals == NULL) + return; + for (Expression_list::const_iterator pe = lhs->begin(); + pe != lhs->end(); + ++pe) + { + if ((*pe)->is_error_expression()) + return; + if (op != OPERATOR_EQ && (*pe)->is_sink_expression()) + error_at((*pe)->location(), "cannot use _ as value"); + } + for (Expression_list::const_iterator pe = vals->begin(); + pe != vals->end(); + ++pe) + { + if ((*pe)->is_error_expression()) + return; + } + + // Map expressions act differently when they are lvalues. + for (Expression_list::iterator plv = lhs->begin(); + plv != lhs->end(); + ++plv) + if ((*plv)->index_expression() != NULL) + (*plv)->index_expression()->set_is_lvalue(); + + Call_expression* call; + Index_expression* map_index; + Receive_expression* receive; + Type_guard_expression* type_guard; + if (lhs->size() == vals->size()) + { + Statement* s; + if (lhs->size() > 1) + { + if (op != OPERATOR_EQ) + error_at(location, "multiple values only permitted with %<=%>"); + s = Statement::make_tuple_assignment(lhs, vals, location); + } + else + { + if (op == OPERATOR_EQ) + s = Statement::make_assignment(lhs->front(), vals->front(), + location); + else + s = Statement::make_assignment_operation(op, lhs->front(), + vals->front(), location); + delete lhs; + delete vals; + } + this->gogo_->add_statement(s); + } + else if (vals->size() == 1 + && (call = (*vals->begin())->call_expression()) != NULL) + { + if (op != OPERATOR_EQ) + error_at(location, "multiple results only permitted with %<=%>"); + delete vals; + vals = new Expression_list; + for (unsigned int i = 0; i < lhs->size(); ++i) + vals->push_back(Expression::make_call_result(call, i)); + Statement* s = Statement::make_tuple_assignment(lhs, vals, location); + this->gogo_->add_statement(s); + } + else if (lhs->size() == 2 + && vals->size() == 1 + && (map_index = (*vals->begin())->index_expression()) != NULL) + { + if (op != OPERATOR_EQ) + error_at(location, "two values from map requires %<=%>"); + Expression* val = lhs->front(); + Expression* present = lhs->back(); + Statement* s = Statement::make_tuple_map_assignment(val, present, + map_index, location); + this->gogo_->add_statement(s); + } + else if (lhs->size() == 1 + && vals->size() == 2 + && (map_index = lhs->front()->index_expression()) != NULL) + { + if (op != OPERATOR_EQ) + error_at(location, "assigning tuple to map index requires %<=%>"); + Expression* val = vals->front(); + Expression* should_set = vals->back(); + Statement* s = Statement::make_map_assignment(map_index, val, should_set, + location); + this->gogo_->add_statement(s); + } + else if (lhs->size() == 2 + && vals->size() == 1 + && (receive = (*vals->begin())->receive_expression()) != NULL) + { + if (op != OPERATOR_EQ) + error_at(location, "two values from receive requires %<=%>"); + Expression* val = lhs->front(); + Expression* success = lhs->back(); + Expression* channel = receive->channel(); + Statement* s = Statement::make_tuple_receive_assignment(val, success, + channel, + location); + this->gogo_->add_statement(s); + } + else if (lhs->size() == 2 + && vals->size() == 1 + && (type_guard = (*vals->begin())->type_guard_expression()) != NULL) + { + if (op != OPERATOR_EQ) + error_at(location, "two values from type guard requires %<=%>"); + Expression* val = lhs->front(); + Expression* ok = lhs->back(); + Expression* expr = type_guard->expr(); + Type* type = type_guard->type(); + Statement* s = Statement::make_tuple_type_guard_assignment(val, ok, + expr, type, + location); + this->gogo_->add_statement(s); + } + else + { + error_at(location, "number of variables does not match number of values"); + } +} + +// GoStat = "go" Expression . +// DeferStat = "defer" Expression . + +void +Parse::go_or_defer_stat() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_GO) + || this->peek_token()->is_keyword(KEYWORD_DEFER)); + bool is_go = this->peek_token()->is_keyword(KEYWORD_GO); + source_location stat_location = this->location(); + this->advance_token(); + source_location expr_location = this->location(); + Expression* expr = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + Call_expression* call_expr = expr->call_expression(); + if (call_expr == NULL) + { + error_at(expr_location, "expected call expression"); + return; + } + + // Make it easier to simplify go/defer statements by putting every + // statement in its own block. + this->gogo_->start_block(stat_location); + Statement* stat; + if (is_go) + stat = Statement::make_go_statement(call_expr, stat_location); + else + stat = Statement::make_defer_statement(call_expr, stat_location); + this->gogo_->add_statement(stat); + this->gogo_->add_block(this->gogo_->finish_block(stat_location), + stat_location); +} + +// ReturnStat = "return" [ ExpressionList ] . + +void +Parse::return_stat() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_RETURN)); + source_location location = this->location(); + this->advance_token(); + Expression_list* vals = NULL; + if (this->expression_may_start_here()) + vals = this->expression_list(NULL, false); + const Function* function = this->gogo_->current_function()->func_value(); + const Typed_identifier_list* results = function->type()->results(); + this->gogo_->add_statement(Statement::make_return_statement(results, vals, + location)); +} + +// IfStat = "if" [ [ SimpleStat ] ";" ] [ Condition ] +// Block [ "else" Statement ] . + +void +Parse::if_stat() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_IF)); + source_location location = this->location(); + this->advance_token(); + + this->gogo_->start_block(location); + + Expression* cond = NULL; + if (this->simple_stat_may_start_here()) + cond = this->simple_stat(false, true, NULL, NULL); + if (cond != NULL && this->peek_token()->is_op(OPERATOR_SEMICOLON)) + { + // The SimpleStat is an expression statement. + this->expression_stat(cond); + cond = NULL; + } + if (cond == NULL) + { + if (this->peek_token()->is_op(OPERATOR_SEMICOLON)) + this->advance_token(); + if (!this->peek_token()->is_op(OPERATOR_LCURLY)) + cond = this->expression(PRECEDENCE_NORMAL, false, false, NULL); + } + + this->gogo_->start_block(this->location()); + source_location end_loc = this->block(); + Block* then_block = this->gogo_->finish_block(end_loc); + + // Check for the easy error of a newline before "else". + if (this->peek_token()->is_op(OPERATOR_SEMICOLON)) + { + source_location semi_loc = this->location(); + if (this->advance_token()->is_keyword(KEYWORD_ELSE)) + error_at(this->location(), + "unexpected semicolon or newline before %<else%>"); + else + this->unget_token(Token::make_operator_token(OPERATOR_SEMICOLON, + semi_loc)); + } + + Block* else_block = NULL; + if (this->peek_token()->is_keyword(KEYWORD_ELSE)) + { + this->advance_token(); + // We create a block to gather the statement. + this->gogo_->start_block(this->location()); + this->statement(NULL); + else_block = this->gogo_->finish_block(this->location()); + } + + this->gogo_->add_statement(Statement::make_if_statement(cond, then_block, + else_block, + location)); + + this->gogo_->add_block(this->gogo_->finish_block(this->location()), + location); +} + +// SwitchStmt = ExprSwitchStmt | TypeSwitchStmt . +// ExprSwitchStmt = "switch" [ [ SimpleStat ] ";" ] [ Expression ] +// "{" { ExprCaseClause } "}" . +// TypeSwitchStmt = "switch" [ [ SimpleStat ] ";" ] TypeSwitchGuard +// "{" { TypeCaseClause } "}" . +// TypeSwitchGuard = [ identifier ":=" ] Expression "." "(" "type" ")" . + +void +Parse::switch_stat(const Label* label) +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_SWITCH)); + source_location location = this->location(); + this->advance_token(); + + this->gogo_->start_block(location); + + Expression* switch_val = NULL; + Type_switch type_switch; + if (this->simple_stat_may_start_here()) + switch_val = this->simple_stat(false, true, NULL, &type_switch); + if (switch_val != NULL && this->peek_token()->is_op(OPERATOR_SEMICOLON)) + { + // The SimpleStat is an expression statement. + this->expression_stat(switch_val); + switch_val = NULL; + } + if (switch_val == NULL && !type_switch.found) + { + if (this->peek_token()->is_op(OPERATOR_SEMICOLON)) + this->advance_token(); + if (!this->peek_token()->is_op(OPERATOR_LCURLY)) + { + if (this->peek_token()->is_identifier()) + { + const Token* token = this->peek_token(); + std::string identifier = token->identifier(); + bool is_exported = token->is_identifier_exported(); + source_location id_loc = token->location(); + + token = this->advance_token(); + bool is_coloneq = token->is_op(OPERATOR_COLONEQ); + this->unget_token(Token::make_identifier_token(identifier, + is_exported, + id_loc)); + if (is_coloneq) + { + // This must be a TypeSwitchGuard. + switch_val = this->simple_stat(false, true, NULL, + &type_switch); + if (!type_switch.found) + { + if (switch_val == NULL + || !switch_val->is_error_expression()) + { + error_at(id_loc, "expected type switch assignment"); + switch_val = Expression::make_error(id_loc); + } + } + } + } + if (switch_val == NULL && !type_switch.found) + { + switch_val = this->expression(PRECEDENCE_NORMAL, false, false, + &type_switch.found); + if (type_switch.found) + { + type_switch.name.clear(); + type_switch.expr = switch_val; + type_switch.location = switch_val->location(); + } + } + } + } + + if (!this->peek_token()->is_op(OPERATOR_LCURLY)) + { + source_location token_loc = this->location(); + if (this->peek_token()->is_op(OPERATOR_SEMICOLON) + && this->advance_token()->is_op(OPERATOR_LCURLY)) + error_at(token_loc, "unexpected semicolon or newline before %<{%>"); + else + { + error_at(this->location(), "expected %<{%>"); + this->gogo_->add_block(this->gogo_->finish_block(this->location()), + location); + return; + } + } + this->advance_token(); + + Statement* statement; + if (type_switch.found) + statement = this->type_switch_body(label, type_switch, location); + else + statement = this->expr_switch_body(label, switch_val, location); + + if (statement != NULL) + this->gogo_->add_statement(statement); + + this->gogo_->add_block(this->gogo_->finish_block(this->location()), + location); +} + +// The body of an expression switch. +// "{" { ExprCaseClause } "}" + +Statement* +Parse::expr_switch_body(const Label* label, Expression* switch_val, + source_location location) +{ + Switch_statement* statement = Statement::make_switch_statement(switch_val, + location); + + this->push_break_statement(statement, label); + + Case_clauses* case_clauses = new Case_clauses(); + bool saw_default = false; + while (!this->peek_token()->is_op(OPERATOR_RCURLY)) + { + if (this->peek_token()->is_eof()) + { + if (!saw_errors()) + error_at(this->location(), "missing %<}%>"); + return NULL; + } + this->expr_case_clause(case_clauses, &saw_default); + } + this->advance_token(); + + statement->add_clauses(case_clauses); + + this->pop_break_statement(); + + return statement; +} + +// ExprCaseClause = ExprSwitchCase ":" [ StatementList ] . +// FallthroughStat = "fallthrough" . + +void +Parse::expr_case_clause(Case_clauses* clauses, bool* saw_default) +{ + source_location location = this->location(); + + bool is_default = false; + Expression_list* vals = this->expr_switch_case(&is_default); + + if (!this->peek_token()->is_op(OPERATOR_COLON)) + { + if (!saw_errors()) + error_at(this->location(), "expected %<:%>"); + return; + } + else + this->advance_token(); + + Block* statements = NULL; + if (this->statement_list_may_start_here()) + { + this->gogo_->start_block(this->location()); + this->statement_list(); + statements = this->gogo_->finish_block(this->location()); + } + + bool is_fallthrough = false; + if (this->peek_token()->is_keyword(KEYWORD_FALLTHROUGH)) + { + is_fallthrough = true; + if (this->advance_token()->is_op(OPERATOR_SEMICOLON)) + this->advance_token(); + } + + if (is_default) + { + if (*saw_default) + { + error_at(location, "multiple defaults in switch"); + return; + } + *saw_default = true; + } + + if (is_default || vals != NULL) + clauses->add(vals, is_default, statements, is_fallthrough, location); +} + +// ExprSwitchCase = "case" ExpressionList | "default" . + +Expression_list* +Parse::expr_switch_case(bool* is_default) +{ + const Token* token = this->peek_token(); + if (token->is_keyword(KEYWORD_CASE)) + { + this->advance_token(); + return this->expression_list(NULL, false); + } + else if (token->is_keyword(KEYWORD_DEFAULT)) + { + this->advance_token(); + *is_default = true; + return NULL; + } + else + { + if (!saw_errors()) + error_at(this->location(), "expected %<case%> or %<default%>"); + if (!token->is_op(OPERATOR_RCURLY)) + this->advance_token(); + return NULL; + } +} + +// The body of a type switch. +// "{" { TypeCaseClause } "}" . + +Statement* +Parse::type_switch_body(const Label* label, const Type_switch& type_switch, + source_location location) +{ + Named_object* switch_no = NULL; + if (!type_switch.name.empty()) + { + Variable* switch_var = new Variable(NULL, type_switch.expr, false, false, + false, type_switch.location); + switch_no = this->gogo_->add_variable(type_switch.name, switch_var); + } + + Type_switch_statement* statement = + Statement::make_type_switch_statement(switch_no, + (switch_no == NULL + ? type_switch.expr + : NULL), + location); + + this->push_break_statement(statement, label); + + Type_case_clauses* case_clauses = new Type_case_clauses(); + bool saw_default = false; + while (!this->peek_token()->is_op(OPERATOR_RCURLY)) + { + if (this->peek_token()->is_eof()) + { + error_at(this->location(), "missing %<}%>"); + return NULL; + } + this->type_case_clause(switch_no, case_clauses, &saw_default); + } + this->advance_token(); + + statement->add_clauses(case_clauses); + + this->pop_break_statement(); + + return statement; +} + +// TypeCaseClause = TypeSwitchCase ":" [ StatementList ] . + +void +Parse::type_case_clause(Named_object* switch_no, Type_case_clauses* clauses, + bool* saw_default) +{ + source_location location = this->location(); + + std::vector<Type*> types; + bool is_default = false; + this->type_switch_case(&types, &is_default); + + if (!this->peek_token()->is_op(OPERATOR_COLON)) + error_at(this->location(), "expected %<:%>"); + else + this->advance_token(); + + Block* statements = NULL; + if (this->statement_list_may_start_here()) + { + this->gogo_->start_block(this->location()); + if (switch_no != NULL && types.size() == 1) + { + Type* type = types.front(); + Expression* init = Expression::make_var_reference(switch_no, + location); + init = Expression::make_type_guard(init, type, location); + Variable* v = new Variable(type, init, false, false, false, + location); + v->set_is_type_switch_var(); + this->gogo_->add_variable(switch_no->name(), v); + } + this->statement_list(); + statements = this->gogo_->finish_block(this->location()); + } + + if (this->peek_token()->is_keyword(KEYWORD_FALLTHROUGH)) + { + error_at(this->location(), + "fallthrough is not permitted in a type switch"); + if (this->advance_token()->is_op(OPERATOR_SEMICOLON)) + this->advance_token(); + } + + if (is_default) + { + gcc_assert(types.empty()); + if (*saw_default) + { + error_at(location, "multiple defaults in type switch"); + return; + } + *saw_default = true; + clauses->add(NULL, false, true, statements, location); + } + else if (!types.empty()) + { + for (std::vector<Type*>::const_iterator p = types.begin(); + p + 1 != types.end(); + ++p) + clauses->add(*p, true, false, NULL, location); + clauses->add(types.back(), false, false, statements, location); + } + else + clauses->add(Type::make_error_type(), false, false, statements, location); +} + +// TypeSwitchCase = "case" type | "default" + +// We accept a comma separated list of types. + +void +Parse::type_switch_case(std::vector<Type*>* types, bool* is_default) +{ + const Token* token = this->peek_token(); + if (token->is_keyword(KEYWORD_CASE)) + { + this->advance_token(); + while (true) + { + Type* t = this->type(); + if (!t->is_error_type()) + types->push_back(t); + if (!this->peek_token()->is_op(OPERATOR_COMMA)) + break; + this->advance_token(); + } + } + else if (token->is_keyword(KEYWORD_DEFAULT)) + { + this->advance_token(); + *is_default = true; + } + else + { + error_at(this->location(), "expected %<case%> or %<default%>"); + if (!token->is_op(OPERATOR_RCURLY)) + this->advance_token(); + } +} + +// SelectStat = "select" "{" { CommClause } "}" . + +void +Parse::select_stat(const Label* label) +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_SELECT)); + source_location location = this->location(); + const Token* token = this->advance_token(); + + if (!token->is_op(OPERATOR_LCURLY)) + { + source_location token_loc = token->location(); + if (token->is_op(OPERATOR_SEMICOLON) + && this->advance_token()->is_op(OPERATOR_LCURLY)) + error_at(token_loc, "unexpected semicolon or newline before %<{%>"); + else + { + error_at(this->location(), "expected %<{%>"); + return; + } + } + this->advance_token(); + + Select_statement* statement = Statement::make_select_statement(location); + + this->push_break_statement(statement, label); + + Select_clauses* select_clauses = new Select_clauses(); + bool saw_default = false; + while (!this->peek_token()->is_op(OPERATOR_RCURLY)) + { + if (this->peek_token()->is_eof()) + { + error_at(this->location(), "expected %<}%>"); + return; + } + this->comm_clause(select_clauses, &saw_default); + } + + this->advance_token(); + + statement->add_clauses(select_clauses); + + this->pop_break_statement(); + + this->gogo_->add_statement(statement); +} + +// CommClause = CommCase [ StatementList ] . + +void +Parse::comm_clause(Select_clauses* clauses, bool* saw_default) +{ + source_location location = this->location(); + bool is_send = false; + Expression* channel = NULL; + Expression* val = NULL; + std::string varname; + bool is_default = false; + bool got_case = this->comm_case(&is_send, &channel, &val, &varname, + &is_default); + + Block* statements = NULL; + Named_object* var = NULL; + if (this->peek_token()->is_op(OPERATOR_SEMICOLON)) + this->advance_token(); + else if (this->statement_list_may_start_here()) + { + this->gogo_->start_block(this->location()); + + if (!varname.empty()) + { + // FIXME: LOCATION is slightly wrong here. + Variable* v = new Variable(NULL, channel, false, false, false, + location); + v->set_type_from_chan_element(); + var = this->gogo_->add_variable(varname, v); + } + + this->statement_list(); + statements = this->gogo_->finish_block(this->location()); + } + + if (is_default) + { + if (*saw_default) + { + error_at(location, "multiple defaults in select"); + return; + } + *saw_default = true; + } + + if (got_case) + clauses->add(is_send, channel, val, var, is_default, statements, location); + else if (statements != NULL) + { + // Add the statements to make sure that any names they define + // are traversed. + this->gogo_->add_block(statements, location); + } +} + +// CommCase = ( "default" | ( "case" ( SendExpr | RecvExpr) ) ) ":" . + +bool +Parse::comm_case(bool* is_send, Expression** channel, Expression** val, + std::string* varname, bool* is_default) +{ + const Token* token = this->peek_token(); + if (token->is_keyword(KEYWORD_DEFAULT)) + { + this->advance_token(); + *is_default = true; + } + else if (token->is_keyword(KEYWORD_CASE)) + { + this->advance_token(); + if (!this->send_or_recv_expr(is_send, channel, val, varname)) + return false; + } + else + { + error_at(this->location(), "expected %<case%> or %<default%>"); + if (!token->is_op(OPERATOR_RCURLY)) + this->advance_token(); + return false; + } + + if (!this->peek_token()->is_op(OPERATOR_COLON)) + { + error_at(this->location(), "expected colon"); + return false; + } + + this->advance_token(); + + return true; +} + +// SendExpr = Expression "<-" Expression . +// RecvExpr = [ Expression ( "=" | ":=" ) ] "<-" Expression . + +bool +Parse::send_or_recv_expr(bool* is_send, Expression** channel, Expression** val, + std::string* varname) +{ + const Token* token = this->peek_token(); + source_location location = token->location(); + if (token->is_identifier()) + { + std::string recv_var = token->identifier(); + bool is_var_exported = token->is_identifier_exported(); + if (!this->advance_token()->is_op(OPERATOR_COLONEQ)) + this->unget_token(Token::make_identifier_token(recv_var, + is_var_exported, + location)); + else + { + if (!this->advance_token()->is_op(OPERATOR_CHANOP)) + { + error_at(this->location(), "expected %<<-%>"); + return false; + } + *is_send = false; + *varname = this->gogo_->pack_hidden_name(recv_var, is_var_exported); + this->advance_token(); + *channel = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + return true; + } + } + + if (this->peek_token()->is_op(OPERATOR_CHANOP)) + { + *is_send = false; + this->advance_token(); + *channel = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + } + else + { + Expression* left = this->expression(PRECEDENCE_CHANOP, true, true, NULL); + + if (this->peek_token()->is_op(OPERATOR_EQ)) + { + if (!this->advance_token()->is_op(OPERATOR_CHANOP)) + { + error_at(this->location(), "missing %<<-%>"); + return false; + } + *is_send = false; + *val = left; + this->advance_token(); + *channel = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + } + else if (this->peek_token()->is_op(OPERATOR_CHANOP)) + { + *is_send = true; + *channel = this->verify_not_sink(left); + this->advance_token(); + *val = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + } + else + { + error_at(this->location(), "expected %<<-%> or %<=%>"); + return false; + } + } + + return true; +} + +// ForStat = "for" [ Condition | ForClause | RangeClause ] Block . +// Condition = Expression . + +void +Parse::for_stat(const Label* label) +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_FOR)); + source_location location = this->location(); + const Token* token = this->advance_token(); + + // Open a block to hold any variables defined in the init statement + // of the for statement. + this->gogo_->start_block(location); + + Block* init = NULL; + Expression* cond = NULL; + Block* post = NULL; + Range_clause range_clause; + + if (!token->is_op(OPERATOR_LCURLY)) + { + if (token->is_keyword(KEYWORD_VAR)) + { + error_at(this->location(), + "var declaration not allowed in for initializer"); + this->var_decl(); + } + + if (token->is_op(OPERATOR_SEMICOLON)) + this->for_clause(&cond, &post); + else + { + // We might be looking at a Condition, an InitStat, or a + // RangeClause. + cond = this->simple_stat(false, true, &range_clause, NULL); + if (!this->peek_token()->is_op(OPERATOR_SEMICOLON)) + { + if (cond == NULL && !range_clause.found) + error_at(this->location(), "parse error in for statement"); + } + else + { + if (range_clause.found) + error_at(this->location(), "parse error after range clause"); + + if (cond != NULL) + { + // COND is actually an expression statement for + // InitStat at the start of a ForClause. + this->expression_stat(cond); + cond = NULL; + } + + this->for_clause(&cond, &post); + } + } + } + + // Build the For_statement and note that it is the current target + // for break and continue statements. + + For_statement* sfor; + For_range_statement* srange; + Statement* s; + if (!range_clause.found) + { + sfor = Statement::make_for_statement(init, cond, post, location); + s = sfor; + srange = NULL; + } + else + { + srange = Statement::make_for_range_statement(range_clause.index, + range_clause.value, + range_clause.range, + location); + s = srange; + sfor = NULL; + } + + this->push_break_statement(s, label); + this->push_continue_statement(s, label); + + // Gather the block of statements in the loop and add them to the + // For_statement. + + this->gogo_->start_block(this->location()); + source_location end_loc = this->block(); + Block* statements = this->gogo_->finish_block(end_loc); + + if (sfor != NULL) + sfor->add_statements(statements); + else + srange->add_statements(statements); + + // This is no longer the break/continue target. + this->pop_break_statement(); + this->pop_continue_statement(); + + // Add the For_statement to the list of statements, and close out + // the block we started to hold any variables defined in the for + // statement. + + this->gogo_->add_statement(s); + + this->gogo_->add_block(this->gogo_->finish_block(this->location()), + location); +} + +// ForClause = [ InitStat ] ";" [ Condition ] ";" [ PostStat ] . +// InitStat = SimpleStat . +// PostStat = SimpleStat . + +// We have already read InitStat at this point. + +void +Parse::for_clause(Expression** cond, Block** post) +{ + gcc_assert(this->peek_token()->is_op(OPERATOR_SEMICOLON)); + this->advance_token(); + if (this->peek_token()->is_op(OPERATOR_SEMICOLON)) + *cond = NULL; + else if (this->peek_token()->is_op(OPERATOR_LCURLY)) + { + error_at(this->location(), + "unexpected semicolon or newline before %<{%>"); + *cond = NULL; + *post = NULL; + return; + } + else + *cond = this->expression(PRECEDENCE_NORMAL, false, true, NULL); + if (!this->peek_token()->is_op(OPERATOR_SEMICOLON)) + error_at(this->location(), "expected semicolon"); + else + this->advance_token(); + + if (this->peek_token()->is_op(OPERATOR_LCURLY)) + *post = NULL; + else + { + this->gogo_->start_block(this->location()); + this->simple_stat(false, false, NULL, NULL); + *post = this->gogo_->finish_block(this->location()); + } +} + +// RangeClause = IdentifierList ( "=" | ":=" ) "range" Expression . + +// This is the := version. It is called with a list of identifiers. + +void +Parse::range_clause_decl(const Typed_identifier_list* til, + Range_clause* p_range_clause) +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_RANGE)); + source_location location = this->location(); + + p_range_clause->found = true; + + gcc_assert(til->size() >= 1); + if (til->size() > 2) + error_at(this->location(), "too many variables for range clause"); + + this->advance_token(); + Expression* expr = this->expression(PRECEDENCE_NORMAL, false, false, NULL); + p_range_clause->range = expr; + + bool any_new = false; + + const Typed_identifier* pti = &til->front(); + Named_object* no = this->init_var(*pti, NULL, expr, true, true, &any_new); + if (any_new && no->is_variable()) + no->var_value()->set_type_from_range_index(); + p_range_clause->index = Expression::make_var_reference(no, location); + + if (til->size() == 1) + p_range_clause->value = NULL; + else + { + pti = &til->back(); + bool is_new = false; + no = this->init_var(*pti, NULL, expr, true, true, &is_new); + if (is_new && no->is_variable()) + no->var_value()->set_type_from_range_value(); + if (is_new) + any_new = true; + p_range_clause->value = Expression::make_var_reference(no, location); + } + + if (!any_new) + error_at(location, "variables redeclared but no variable is new"); +} + +// The = version of RangeClause. This is called with a list of +// expressions. + +void +Parse::range_clause_expr(const Expression_list* vals, + Range_clause* p_range_clause) +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_RANGE)); + + p_range_clause->found = true; + + gcc_assert(vals->size() >= 1); + if (vals->size() > 2) + error_at(this->location(), "too many variables for range clause"); + + this->advance_token(); + p_range_clause->range = this->expression(PRECEDENCE_NORMAL, false, false, + NULL); + + p_range_clause->index = vals->front(); + if (vals->size() == 1) + p_range_clause->value = NULL; + else + p_range_clause->value = vals->back(); +} + +// Push a statement on the break stack. + +void +Parse::push_break_statement(Statement* enclosing, const Label* label) +{ + if (this->break_stack_ == NULL) + this->break_stack_ = new Bc_stack(); + this->break_stack_->push_back(std::make_pair(enclosing, label)); +} + +// Push a statement on the continue stack. + +void +Parse::push_continue_statement(Statement* enclosing, const Label* label) +{ + if (this->continue_stack_ == NULL) + this->continue_stack_ = new Bc_stack(); + this->continue_stack_->push_back(std::make_pair(enclosing, label)); +} + +// Pop the break stack. + +void +Parse::pop_break_statement() +{ + this->break_stack_->pop_back(); +} + +// Pop the continue stack. + +void +Parse::pop_continue_statement() +{ + this->continue_stack_->pop_back(); +} + +// Find a break or continue statement given a label name. + +Statement* +Parse::find_bc_statement(const Bc_stack* bc_stack, const std::string& label) +{ + if (bc_stack == NULL) + return NULL; + for (Bc_stack::const_reverse_iterator p = bc_stack->rbegin(); + p != bc_stack->rend(); + ++p) + if (p->second != NULL && p->second->name() == label) + return p->first; + return NULL; +} + +// BreakStat = "break" [ identifier ] . + +void +Parse::break_stat() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_BREAK)); + source_location location = this->location(); + + const Token* token = this->advance_token(); + Statement* enclosing; + if (!token->is_identifier()) + { + if (this->break_stack_ == NULL || this->break_stack_->empty()) + { + error_at(this->location(), + "break statement not within for or switch or select"); + return; + } + enclosing = this->break_stack_->back().first; + } + else + { + enclosing = this->find_bc_statement(this->break_stack_, + token->identifier()); + if (enclosing == NULL) + { + error_at(token->location(), + ("break label %qs not associated with " + "for or switch or select"), + Gogo::message_name(token->identifier()).c_str()); + this->advance_token(); + return; + } + this->advance_token(); + } + + Unnamed_label* label; + if (enclosing->classification() == Statement::STATEMENT_FOR) + label = enclosing->for_statement()->break_label(); + else if (enclosing->classification() == Statement::STATEMENT_FOR_RANGE) + label = enclosing->for_range_statement()->break_label(); + else if (enclosing->classification() == Statement::STATEMENT_SWITCH) + label = enclosing->switch_statement()->break_label(); + else if (enclosing->classification() == Statement::STATEMENT_TYPE_SWITCH) + label = enclosing->type_switch_statement()->break_label(); + else if (enclosing->classification() == Statement::STATEMENT_SELECT) + label = enclosing->select_statement()->break_label(); + else + gcc_unreachable(); + + this->gogo_->add_statement(Statement::make_break_statement(label, + location)); +} + +// ContinueStat = "continue" [ identifier ] . + +void +Parse::continue_stat() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_CONTINUE)); + source_location location = this->location(); + + const Token* token = this->advance_token(); + Statement* enclosing; + if (!token->is_identifier()) + { + if (this->continue_stack_ == NULL || this->continue_stack_->empty()) + { + error_at(this->location(), "continue statement not within for"); + return; + } + enclosing = this->continue_stack_->back().first; + } + else + { + enclosing = this->find_bc_statement(this->continue_stack_, + token->identifier()); + if (enclosing == NULL) + { + error_at(token->location(), + "continue label %qs not associated with for", + Gogo::message_name(token->identifier()).c_str()); + this->advance_token(); + return; + } + this->advance_token(); + } + + Unnamed_label* label; + if (enclosing->classification() == Statement::STATEMENT_FOR) + label = enclosing->for_statement()->continue_label(); + else if (enclosing->classification() == Statement::STATEMENT_FOR_RANGE) + label = enclosing->for_range_statement()->continue_label(); + else + gcc_unreachable(); + + this->gogo_->add_statement(Statement::make_continue_statement(label, + location)); +} + +// GotoStat = "goto" identifier . + +void +Parse::goto_stat() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_GOTO)); + source_location location = this->location(); + const Token* token = this->advance_token(); + if (!token->is_identifier()) + error_at(this->location(), "expected label for goto"); + else + { + Label* label = this->gogo_->add_label_reference(token->identifier()); + Statement* s = Statement::make_goto_statement(label, location); + this->gogo_->add_statement(s); + this->advance_token(); + } +} + +// PackageClause = "package" PackageName . + +void +Parse::package_clause() +{ + const Token* token = this->peek_token(); + source_location location = token->location(); + std::string name; + if (!token->is_keyword(KEYWORD_PACKAGE)) + { + error_at(this->location(), "program must start with package clause"); + name = "ERROR"; + } + else + { + token = this->advance_token(); + if (token->is_identifier()) + { + name = token->identifier(); + if (name == "_") + { + error_at(this->location(), "invalid package name _"); + name = "blank"; + } + this->advance_token(); + } + else + { + error_at(this->location(), "package name must be an identifier"); + name = "ERROR"; + } + } + this->gogo_->set_package_name(name, location); +} + +// ImportDecl = "import" Decl<ImportSpec> . + +void +Parse::import_decl() +{ + gcc_assert(this->peek_token()->is_keyword(KEYWORD_IMPORT)); + this->advance_token(); + this->decl(&Parse::import_spec, NULL); +} + +// ImportSpec = [ "." | PackageName ] PackageFileName . + +void +Parse::import_spec(void*) +{ + const Token* token = this->peek_token(); + source_location location = token->location(); + + std::string local_name; + bool is_local_name_exported = false; + if (token->is_op(OPERATOR_DOT)) + { + local_name = "."; + token = this->advance_token(); + } + else if (token->is_identifier()) + { + local_name = token->identifier(); + is_local_name_exported = token->is_identifier_exported(); + token = this->advance_token(); + } + + if (!token->is_string()) + { + error_at(this->location(), "missing import package name"); + return; + } + + this->gogo_->import_package(token->string_value(), local_name, + is_local_name_exported, location); + + this->advance_token(); +} + +// SourceFile = PackageClause ";" { ImportDecl ";" } +// { TopLevelDecl ";" } . + +void +Parse::program() +{ + this->package_clause(); + + const Token* token = this->peek_token(); + if (token->is_op(OPERATOR_SEMICOLON)) + token = this->advance_token(); + else + error_at(this->location(), + "expected %<;%> or newline after package clause"); + + while (token->is_keyword(KEYWORD_IMPORT)) + { + this->import_decl(); + token = this->peek_token(); + if (token->is_op(OPERATOR_SEMICOLON)) + token = this->advance_token(); + else + error_at(this->location(), + "expected %<;%> or newline after import declaration"); + } + + while (!token->is_eof()) + { + if (this->declaration_may_start_here()) + this->declaration(); + else + { + error_at(this->location(), "expected declaration"); + do + this->advance_token(); + while (!this->peek_token()->is_eof() + && !this->peek_token()->is_op(OPERATOR_SEMICOLON) + && !this->peek_token()->is_op(OPERATOR_RCURLY)); + if (!this->peek_token()->is_eof() + && !this->peek_token()->is_op(OPERATOR_SEMICOLON)) + this->advance_token(); + } + token = this->peek_token(); + if (token->is_op(OPERATOR_SEMICOLON)) + token = this->advance_token(); + else if (!token->is_eof() || !saw_errors()) + { + error_at(this->location(), + "expected %<;%> or newline after top level declaration"); + this->skip_past_error(OPERATOR_INVALID); + } + } +} + +// Reset the current iota value. + +void +Parse::reset_iota() +{ + this->iota_ = 0; +} + +// Return the current iota value. + +int +Parse::iota_value() +{ + return this->iota_; +} + +// Increment the current iota value. + +void +Parse::increment_iota() +{ + ++this->iota_; +} + +// Skip forward to a semicolon or OP. OP will normally be +// OPERATOR_RPAREN or OPERATOR_RCURLY. If we find a semicolon, move +// past it and return. If we find OP, it will be the next token to +// read. Return true if we are OK, false if we found EOF. + +bool +Parse::skip_past_error(Operator op) +{ + const Token* token = this->peek_token(); + while (!token->is_op(op)) + { + if (token->is_eof()) + return false; + if (token->is_op(OPERATOR_SEMICOLON)) + { + this->advance_token(); + return true; + } + token = this->advance_token(); + } + return true; +} + +// Check that an expression is not a sink. + +Expression* +Parse::verify_not_sink(Expression* expr) +{ + if (expr->is_sink_expression()) + { + error_at(expr->location(), "cannot use _ as value"); + expr = Expression::make_error(expr->location()); + } + return expr; +} diff --git a/gcc/go/gofrontend/parse.h b/gcc/go/gofrontend/parse.h new file mode 100644 index 000000000..6f2ac64b1 --- /dev/null +++ b/gcc/go/gofrontend/parse.h @@ -0,0 +1,308 @@ +// parse.h -- Go frontend parser. -*- C++ -*- + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef GO_PARSE_H +#define GO_PARSE_H + +class Set_iota_traverse; +class Lex; +class Gogo; +class Named_object; +class Type; +class Typed_identifier; +class Typed_identifier_list; +class Function_type; +class Block; +class Expression; +class Expression_list; +class Struct_field_list; +class Case_clauses; +class Type_case_clauses; +class Select_clauses; +class Statement; +class Label; + +// Parse the program. + +class Parse +{ + public: + Parse(Lex*, Gogo*); + + // Parse a program. + void + program(); + + private: + // Precedence values. + enum Precedence + { + PRECEDENCE_INVALID = -1, + PRECEDENCE_NORMAL = 0, + PRECEDENCE_OROR, + PRECEDENCE_ANDAND, + PRECEDENCE_CHANOP, + PRECEDENCE_RELOP, + PRECEDENCE_ADDOP, + PRECEDENCE_MULOP + }; + + // We use this when parsing the range clause of a for statement. + struct Range_clause + { + // Set to true if we found a range clause. + bool found; + // The index expression. + Expression* index; + // The value expression. + Expression* value; + // The range expression. + Expression* range; + + Range_clause() + : found(false), index(NULL), value(NULL), range(NULL) + { } + }; + + // We use this when parsing the statement at the start of a switch, + // in order to recognize type switches. + struct Type_switch + { + // Set to true if we find a type switch. + bool found; + // The variable name. + std::string name; + // The location of the variable. + source_location location; + // The expression. + Expression* expr; + + Type_switch() + : found(false), name(), location(UNKNOWN_LOCATION), expr(NULL) + { } + }; + + // A variable defined in an enclosing function referenced by the + // current function. + class Enclosing_var + { + public: + Enclosing_var(Named_object* var, Named_object* in_function, + unsigned int index) + : var_(var), in_function_(in_function), index_(index) + { } + + // We put these in a vector, so we need a default constructor. + Enclosing_var() + : var_(NULL), in_function_(NULL), index_(-1U) + { } + + Named_object* + var() const + { return this->var_; } + + Named_object* + in_function() const + { return this->in_function_; } + + unsigned int + index() const + { return this->index_; } + + private: + // The variable which is being referred to. + Named_object* var_; + // The function where the variable is defined. + Named_object* in_function_; + // The index of the field in this function's closure struct for + // this variable. + unsigned int index_; + }; + + // We store Enclosing_var entries in a set, so we need a comparator. + struct Enclosing_var_comparison + { + bool + operator()(const Enclosing_var&, const Enclosing_var&); + }; + + // A set of Enclosing_var entries. + typedef std::set<Enclosing_var, Enclosing_var_comparison> Enclosing_vars; + + // Peek at the current token from the lexer. + const Token* + peek_token(); + + // Consume the current token, return the next one. + const Token* + advance_token(); + + // Push a token back on the input stream. + void + unget_token(const Token&); + + // The location of the current token. + source_location + location(); + + // For break and continue we keep a stack of statements with + // associated labels (if any). The top of the stack is used for a + // break or continue statement with no label. + typedef std::vector<std::pair<Statement*, const Label*> > Bc_stack; + + // Parser nonterminals. + void identifier_list(Typed_identifier_list*); + Expression_list* expression_list(Expression*, bool may_be_sink); + bool qualified_ident(std::string*, Named_object**); + Type* type(); + bool type_may_start_here(); + Type* type_name(bool issue_error); + Type* array_type(bool may_use_ellipsis); + Type* map_type(); + Type* struct_type(); + void field_decl(Struct_field_list*); + Type* pointer_type(); + Type* channel_type(); + Function_type* signature(Typed_identifier*, source_location); + bool parameters(Typed_identifier_list**, bool* is_varargs); + Typed_identifier_list* parameter_list(bool* is_varargs); + void parameter_decl(bool, Typed_identifier_list*, bool*, bool*); + bool result(Typed_identifier_list**); + source_location block(); + Type* interface_type(); + void method_spec(Typed_identifier_list*); + void declaration(); + bool declaration_may_start_here(); + void decl(void (Parse::*)(void*), void*); + void list(void (Parse::*)(void*), void*, bool); + void const_decl(); + void const_spec(Type**, Expression_list**); + void type_decl(); + void type_spec(void*); + void var_decl(); + void var_spec(void*); + void init_vars(const Typed_identifier_list*, Type*, Expression_list*, + bool is_coloneq, source_location); + bool init_vars_from_call(const Typed_identifier_list*, Type*, Expression*, + bool is_coloneq, source_location); + bool init_vars_from_map(const Typed_identifier_list*, Type*, Expression*, + bool is_coloneq, source_location); + bool init_vars_from_receive(const Typed_identifier_list*, Type*, + Expression*, bool is_coloneq, source_location); + bool init_vars_from_type_guard(const Typed_identifier_list*, Type*, + Expression*, bool is_coloneq, + source_location); + Named_object* init_var(const Typed_identifier&, Type*, Expression*, + bool is_coloneq, bool type_from_init, bool* is_new); + Named_object* create_dummy_global(Type*, Expression*, source_location); + void simple_var_decl_or_assignment(const std::string&, source_location, + Range_clause*, Type_switch*); + void function_decl(); + Typed_identifier* receiver(); + Expression* operand(bool may_be_sink); + Expression* enclosing_var_reference(Named_object*, Named_object*, + source_location); + Expression* composite_lit(Type*, int depth, source_location); + Expression* function_lit(); + Expression* create_closure(Named_object* function, Enclosing_vars*, + source_location); + Expression* primary_expr(bool may_be_sink, bool may_be_composite_lit, + bool* is_type_switch); + Expression* selector(Expression*, bool* is_type_switch); + Expression* index(Expression*); + Expression* call(Expression*); + Expression* expression(Precedence, bool may_be_sink, + bool may_be_composite_lit, bool* is_type_switch); + bool expression_may_start_here(); + Expression* unary_expr(bool may_be_sink, bool may_be_composite_lit, + bool* is_type_switch); + Expression* qualified_expr(Expression*, source_location); + Expression* id_to_expression(const std::string&, source_location); + void statement(const Label*); + bool statement_may_start_here(); + void labeled_stmt(const std::string&, source_location); + Expression* simple_stat(bool, bool, Range_clause*, Type_switch*); + bool simple_stat_may_start_here(); + void statement_list(); + bool statement_list_may_start_here(); + void expression_stat(Expression*); + void inc_dec_stat(Expression*); + void assignment(Expression*, Range_clause*); + void tuple_assignment(Expression_list*, Range_clause*); + void send(); + void go_or_defer_stat(); + void return_stat(); + void if_stat(); + void switch_stat(const Label*); + Statement* expr_switch_body(const Label*, Expression*, source_location); + void expr_case_clause(Case_clauses*, bool* saw_default); + Expression_list* expr_switch_case(bool*); + Statement* type_switch_body(const Label*, const Type_switch&, + source_location); + void type_case_clause(Named_object*, Type_case_clauses*, bool* saw_default); + void type_switch_case(std::vector<Type*>*, bool*); + void select_stat(const Label*); + void comm_clause(Select_clauses*, bool* saw_default); + bool comm_case(bool*, Expression**, Expression**, std::string*, bool*); + bool send_or_recv_expr(bool*, Expression**, Expression**, std::string*); + void for_stat(const Label*); + void for_clause(Expression**, Block**); + void range_clause_decl(const Typed_identifier_list*, Range_clause*); + void range_clause_expr(const Expression_list*, Range_clause*); + void push_break_statement(Statement*, const Label*); + void push_continue_statement(Statement*, const Label*); + void pop_break_statement(); + void pop_continue_statement(); + Statement* find_bc_statement(const Bc_stack*, const std::string&); + void break_stat(); + void continue_stat(); + void goto_stat(); + void package_clause(); + void import_decl(); + void import_spec(void*); + + void reset_iota(); + int iota_value(); + void increment_iota(); + + // Skip past an error looking for a semicolon or OP. Return true if + // all is well, false if we found EOF. + bool + skip_past_error(Operator op); + + // Verify that an expression is not a sink, and return either the + // expression or an error. + Expression* + verify_not_sink(Expression*); + + // Return the statement associated with a label in a Bc_stack, or + // NULL. + Statement* + find_bc_statement(const Bc_stack*, const std::string&) const; + + // The lexer output we are parsing. + Lex* lex_; + // The current token. + Token token_; + // A token pushed back on the input stream. + Token unget_token_; + // Whether unget_token_ is valid. + bool unget_token_valid_; + // The code we are generating. + Gogo* gogo_; + // A stack of statements for which break may be used. + Bc_stack* break_stack_; + // A stack of statements for which continue may be used. + Bc_stack* continue_stack_; + // The current iota value. + int iota_; + // References from the local function to variables defined in + // enclosing functions. + Enclosing_vars enclosing_vars_; +}; + + +#endif // !defined(GO_PARSE_H) diff --git a/gcc/go/gofrontend/statements.cc b/gcc/go/gofrontend/statements.cc new file mode 100644 index 000000000..c443519b7 --- /dev/null +++ b/gcc/go/gofrontend/statements.cc @@ -0,0 +1,5262 @@ +// statements.cc -- Go frontend statements. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include <gmp.h> + +#ifndef ENABLE_BUILD_WITH_CXX +extern "C" +{ +#endif + +#include "intl.h" +#include "tree.h" +#include "gimple.h" +#include "convert.h" +#include "tree-iterator.h" +#include "tree-flow.h" +#include "real.h" + +#ifndef ENABLE_BUILD_WITH_CXX +} +#endif + +#include "go-c.h" +#include "types.h" +#include "expressions.h" +#include "gogo.h" +#include "statements.h" + +// Class Statement. + +Statement::Statement(Statement_classification classification, + source_location location) + : classification_(classification), location_(location) +{ +} + +Statement::~Statement() +{ +} + +// Traverse the tree. The work of walking the components is handled +// by the subclasses. + +int +Statement::traverse(Block* block, size_t* pindex, Traverse* traverse) +{ + if (this->classification_ == STATEMENT_ERROR) + return TRAVERSE_CONTINUE; + + unsigned int traverse_mask = traverse->traverse_mask(); + + if ((traverse_mask & Traverse::traverse_statements) != 0) + { + int t = traverse->statement(block, pindex, this); + if (t == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + else if (t == TRAVERSE_SKIP_COMPONENTS) + return TRAVERSE_CONTINUE; + } + + // No point in checking traverse_mask here--a statement may contain + // other blocks or statements, and if we got here we always want to + // walk them. + return this->do_traverse(traverse); +} + +// Traverse the contents of a statement. + +int +Statement::traverse_contents(Traverse* traverse) +{ + return this->do_traverse(traverse); +} + +// Traverse assignments. + +bool +Statement::traverse_assignments(Traverse_assignments* tassign) +{ + if (this->classification_ == STATEMENT_ERROR) + return false; + return this->do_traverse_assignments(tassign); +} + +// Traverse an expression in a statement. This is a helper function +// for child classes. + +int +Statement::traverse_expression(Traverse* traverse, Expression** expr) +{ + if ((traverse->traverse_mask() + & (Traverse::traverse_types | Traverse::traverse_expressions)) == 0) + return TRAVERSE_CONTINUE; + return Expression::traverse(expr, traverse); +} + +// Traverse an expression list in a statement. This is a helper +// function for child classes. + +int +Statement::traverse_expression_list(Traverse* traverse, + Expression_list* expr_list) +{ + if (expr_list == NULL) + return TRAVERSE_CONTINUE; + if ((traverse->traverse_mask() + & (Traverse::traverse_types | Traverse::traverse_expressions)) == 0) + return TRAVERSE_CONTINUE; + return expr_list->traverse(traverse); +} + +// Traverse a type in a statement. This is a helper function for +// child classes. + +int +Statement::traverse_type(Traverse* traverse, Type* type) +{ + if ((traverse->traverse_mask() + & (Traverse::traverse_types | Traverse::traverse_expressions)) == 0) + return TRAVERSE_CONTINUE; + return Type::traverse(type, traverse); +} + +// Set type information for unnamed constants. This is really done by +// the child class. + +void +Statement::determine_types() +{ + this->do_determine_types(); +} + +// If this is a thunk statement, return it. + +Thunk_statement* +Statement::thunk_statement() +{ + Thunk_statement* ret = this->convert<Thunk_statement, STATEMENT_GO>(); + if (ret == NULL) + ret = this->convert<Thunk_statement, STATEMENT_DEFER>(); + return ret; +} + +// Get a tree for a Statement. This is really done by the child +// class. + +tree +Statement::get_tree(Translate_context* context) +{ + if (this->classification_ == STATEMENT_ERROR) + return error_mark_node; + + return this->do_get_tree(context); +} + +// Build tree nodes and set locations. + +tree +Statement::build_stmt_1(int tree_code_value, tree node) +{ + tree ret = build1(static_cast<tree_code>(tree_code_value), + void_type_node, node); + SET_EXPR_LOCATION(ret, this->location_); + return ret; +} + +// Note that this statement is erroneous. This is called by children +// when they discover an error. + +void +Statement::set_is_error() +{ + this->classification_ = STATEMENT_ERROR; +} + +// For children to call to report an error conveniently. + +void +Statement::report_error(const char* msg) +{ + error_at(this->location_, "%s", msg); + this->set_is_error(); +} + +// An error statement, used to avoid crashing after we report an +// error. + +class Error_statement : public Statement +{ + public: + Error_statement(source_location location) + : Statement(STATEMENT_ERROR, location) + { } + + protected: + int + do_traverse(Traverse*) + { return TRAVERSE_CONTINUE; } + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } +}; + +// Make an error statement. + +Statement* +Statement::make_error_statement(source_location location) +{ + return new Error_statement(location); +} + +// Class Variable_declaration_statement. + +Variable_declaration_statement::Variable_declaration_statement( + Named_object* var) + : Statement(STATEMENT_VARIABLE_DECLARATION, var->var_value()->location()), + var_(var) +{ +} + +// We don't actually traverse the variable here; it was traversed +// while traversing the Block. + +int +Variable_declaration_statement::do_traverse(Traverse*) +{ + return TRAVERSE_CONTINUE; +} + +// Traverse the assignments in a variable declaration. Note that this +// traversal is different from the usual traversal. + +bool +Variable_declaration_statement::do_traverse_assignments( + Traverse_assignments* tassign) +{ + tassign->initialize_variable(this->var_); + return true; +} + +// Return the tree for a variable declaration. + +tree +Variable_declaration_statement::do_get_tree(Translate_context* context) +{ + tree val = this->var_->get_tree(context->gogo(), context->function()); + if (val == error_mark_node || TREE_TYPE(val) == error_mark_node) + return error_mark_node; + Variable* variable = this->var_->var_value(); + + tree init = variable->get_init_tree(context->gogo(), context->function()); + if (init == error_mark_node) + return error_mark_node; + + // If this variable lives on the heap, we need to allocate it now. + if (!variable->is_in_heap()) + { + DECL_INITIAL(val) = init; + return this->build_stmt_1(DECL_EXPR, val); + } + else + { + gcc_assert(TREE_CODE(val) == INDIRECT_REF); + tree decl = TREE_OPERAND(val, 0); + gcc_assert(TREE_CODE(decl) == VAR_DECL); + tree type = TREE_TYPE(decl); + gcc_assert(POINTER_TYPE_P(type)); + tree size = TYPE_SIZE_UNIT(TREE_TYPE(type)); + tree space = context->gogo()->allocate_memory(variable->type(), size, + this->location()); + space = fold_convert(TREE_TYPE(decl), space); + DECL_INITIAL(decl) = space; + return build2(COMPOUND_EXPR, void_type_node, + this->build_stmt_1(DECL_EXPR, decl), + build2(MODIFY_EXPR, void_type_node, val, init)); + } +} + +// Make a variable declaration. + +Statement* +Statement::make_variable_declaration(Named_object* var) +{ + return new Variable_declaration_statement(var); +} + +// Class Temporary_statement. + +// Return the type of the temporary variable. + +Type* +Temporary_statement::type() const +{ + return this->type_ != NULL ? this->type_ : this->init_->type(); +} + +// Return the tree for the temporary variable. + +tree +Temporary_statement::get_decl() const +{ + if (this->decl_ == NULL) + { + gcc_assert(saw_errors()); + return error_mark_node; + } + return this->decl_; +} + +// Traversal. + +int +Temporary_statement::do_traverse(Traverse* traverse) +{ + if (this->type_ != NULL + && this->traverse_type(traverse, this->type_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (this->init_ == NULL) + return TRAVERSE_CONTINUE; + else + return this->traverse_expression(traverse, &this->init_); +} + +// Traverse assignments. + +bool +Temporary_statement::do_traverse_assignments(Traverse_assignments* tassign) +{ + if (this->init_ == NULL) + return false; + tassign->value(&this->init_, true, true); + return true; +} + +// Determine types. + +void +Temporary_statement::do_determine_types() +{ + if (this->type_ != NULL && this->type_->is_abstract()) + this->type_ = this->type_->make_non_abstract_type(); + + if (this->init_ != NULL) + { + if (this->type_ == NULL) + this->init_->determine_type_no_context(); + else + { + Type_context context(this->type_, false); + this->init_->determine_type(&context); + } + } + + if (this->type_ == NULL) + { + this->type_ = this->init_->type(); + gcc_assert(!this->type_->is_abstract()); + } +} + +// Check types. + +void +Temporary_statement::do_check_types(Gogo*) +{ + if (this->type_ != NULL && this->init_ != NULL) + { + std::string reason; + if (!Type::are_assignable(this->type_, this->init_->type(), &reason)) + { + if (reason.empty()) + error_at(this->location(), "incompatible types in assignment"); + else + error_at(this->location(), "incompatible types in assignment (%s)", + reason.c_str()); + this->set_is_error(); + } + } +} + +// Return a tree. + +tree +Temporary_statement::do_get_tree(Translate_context* context) +{ + gcc_assert(this->decl_ == NULL_TREE); + tree type_tree = this->type()->get_tree(context->gogo()); + tree init_tree = (this->init_ == NULL + ? NULL_TREE + : this->init_->get_tree(context)); + if (type_tree == error_mark_node || init_tree == error_mark_node) + { + this->decl_ = error_mark_node; + return error_mark_node; + } + // We can only use create_tmp_var if the type is not addressable. + if (!TREE_ADDRESSABLE(type_tree)) + { + this->decl_ = create_tmp_var(type_tree, "GOTMP"); + DECL_SOURCE_LOCATION(this->decl_) = this->location(); + } + else + { + gcc_assert(context->function() != NULL && context->block() != NULL); + tree decl = build_decl(this->location(), VAR_DECL, + create_tmp_var_name("GOTMP"), + type_tree); + DECL_ARTIFICIAL(decl) = 1; + DECL_IGNORED_P(decl) = 1; + TREE_USED(decl) = 1; + gcc_assert(current_function_decl != NULL_TREE); + DECL_CONTEXT(decl) = current_function_decl; + + // We have to add this variable to the block so that it winds up + // in a BIND_EXPR. + tree block_tree = context->block_tree(); + gcc_assert(block_tree != NULL_TREE); + DECL_CHAIN(decl) = BLOCK_VARS(block_tree); + BLOCK_VARS(block_tree) = decl; + + this->decl_ = decl; + } + if (init_tree != NULL_TREE) + DECL_INITIAL(this->decl_) = + Expression::convert_for_assignment(context, this->type(), + this->init_->type(), init_tree, + this->location()); + if (this->is_address_taken_) + TREE_ADDRESSABLE(this->decl_) = 1; + return this->build_stmt_1(DECL_EXPR, this->decl_); +} + +// Make and initialize a temporary variable in BLOCK. + +Temporary_statement* +Statement::make_temporary(Type* type, Expression* init, + source_location location) +{ + return new Temporary_statement(type, init, location); +} + +// An assignment statement. + +class Assignment_statement : public Statement +{ + public: + Assignment_statement(Expression* lhs, Expression* rhs, + source_location location) + : Statement(STATEMENT_ASSIGNMENT, location), + lhs_(lhs), rhs_(rhs) + { } + + protected: + int + do_traverse(Traverse* traverse); + + bool + do_traverse_assignments(Traverse_assignments*); + + void + do_determine_types(); + + void + do_check_types(Gogo*); + + tree + do_get_tree(Translate_context*); + + private: + // Left hand side--the lvalue. + Expression* lhs_; + // Right hand side--the rvalue. + Expression* rhs_; +}; + +// Traversal. + +int +Assignment_statement::do_traverse(Traverse* traverse) +{ + if (this->traverse_expression(traverse, &this->lhs_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return this->traverse_expression(traverse, &this->rhs_); +} + +bool +Assignment_statement::do_traverse_assignments(Traverse_assignments* tassign) +{ + tassign->assignment(&this->lhs_, &this->rhs_); + return true; +} + +// Set types for the assignment. + +void +Assignment_statement::do_determine_types() +{ + this->lhs_->determine_type_no_context(); + Type_context context(this->lhs_->type(), false); + this->rhs_->determine_type(&context); +} + +// Check types for an assignment. + +void +Assignment_statement::do_check_types(Gogo*) +{ + // The left hand side must be either addressable, a map index + // expression, or the blank identifier. + if (!this->lhs_->is_addressable() + && this->lhs_->map_index_expression() == NULL + && !this->lhs_->is_sink_expression()) + { + if (!this->lhs_->type()->is_error_type()) + this->report_error(_("invalid left hand side of assignment")); + return; + } + + Type* lhs_type = this->lhs_->type(); + Type* rhs_type = this->rhs_->type(); + std::string reason; + if (!Type::are_assignable(lhs_type, rhs_type, &reason)) + { + if (reason.empty()) + error_at(this->location(), "incompatible types in assignment"); + else + error_at(this->location(), "incompatible types in assignment (%s)", + reason.c_str()); + this->set_is_error(); + } + + if (lhs_type->is_error_type() + || rhs_type->is_error_type() + || lhs_type->is_undefined() + || rhs_type->is_undefined()) + { + // Make sure we get the error for an undefined type. + lhs_type->base(); + rhs_type->base(); + this->set_is_error(); + } +} + +// Build a tree for an assignment statement. + +tree +Assignment_statement::do_get_tree(Translate_context* context) +{ + tree rhs_tree = this->rhs_->get_tree(context); + + if (this->lhs_->is_sink_expression()) + return rhs_tree; + + tree lhs_tree = this->lhs_->get_tree(context); + + if (lhs_tree == error_mark_node || rhs_tree == error_mark_node) + return error_mark_node; + + rhs_tree = Expression::convert_for_assignment(context, this->lhs_->type(), + this->rhs_->type(), rhs_tree, + this->location()); + if (rhs_tree == error_mark_node) + return error_mark_node; + + return fold_build2_loc(this->location(), MODIFY_EXPR, void_type_node, + lhs_tree, rhs_tree); +} + +// Make an assignment statement. + +Statement* +Statement::make_assignment(Expression* lhs, Expression* rhs, + source_location location) +{ + return new Assignment_statement(lhs, rhs, location); +} + +// The Move_ordered_evals class is used to find any subexpressions of +// an expression that have an evaluation order dependency. It creates +// temporary variables to hold them. + +class Move_ordered_evals : public Traverse +{ + public: + Move_ordered_evals(Block* block) + : Traverse(traverse_expressions), + block_(block) + { } + + protected: + int + expression(Expression**); + + private: + // The block where new temporary variables should be added. + Block* block_; +}; + +int +Move_ordered_evals::expression(Expression** pexpr) +{ + // We have to look at subexpressions first. + if ((*pexpr)->traverse_subexpressions(this) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if ((*pexpr)->must_eval_in_order()) + { + source_location loc = (*pexpr)->location(); + Temporary_statement* temp = Statement::make_temporary(NULL, *pexpr, loc); + this->block_->add_statement(temp); + *pexpr = Expression::make_temporary_reference(temp, loc); + } + return TRAVERSE_SKIP_COMPONENTS; +} + +// An assignment operation statement. + +class Assignment_operation_statement : public Statement +{ + public: + Assignment_operation_statement(Operator op, Expression* lhs, Expression* rhs, + source_location location) + : Statement(STATEMENT_ASSIGNMENT_OPERATION, location), + op_(op), lhs_(lhs), rhs_(rhs) + { } + + protected: + int + do_traverse(Traverse*); + + bool + do_traverse_assignments(Traverse_assignments*) + { gcc_unreachable(); } + + Statement* + do_lower(Gogo*, Block*); + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + // The operator (OPERATOR_PLUSEQ, etc.). + Operator op_; + // Left hand side. + Expression* lhs_; + // Right hand side. + Expression* rhs_; +}; + +// Traversal. + +int +Assignment_operation_statement::do_traverse(Traverse* traverse) +{ + if (this->traverse_expression(traverse, &this->lhs_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return this->traverse_expression(traverse, &this->rhs_); +} + +// Lower an assignment operation statement to a regular assignment +// statement. + +Statement* +Assignment_operation_statement::do_lower(Gogo*, Block* enclosing) +{ + source_location loc = this->location(); + + // We have to evaluate the left hand side expression only once. We + // do this by moving out any expression with side effects. + Block* b = new Block(enclosing, loc); + Move_ordered_evals moe(b); + this->lhs_->traverse_subexpressions(&moe); + + Expression* lval = this->lhs_->copy(); + + Operator op; + switch (this->op_) + { + case OPERATOR_PLUSEQ: + op = OPERATOR_PLUS; + break; + case OPERATOR_MINUSEQ: + op = OPERATOR_MINUS; + break; + case OPERATOR_OREQ: + op = OPERATOR_OR; + break; + case OPERATOR_XOREQ: + op = OPERATOR_XOR; + break; + case OPERATOR_MULTEQ: + op = OPERATOR_MULT; + break; + case OPERATOR_DIVEQ: + op = OPERATOR_DIV; + break; + case OPERATOR_MODEQ: + op = OPERATOR_MOD; + break; + case OPERATOR_LSHIFTEQ: + op = OPERATOR_LSHIFT; + break; + case OPERATOR_RSHIFTEQ: + op = OPERATOR_RSHIFT; + break; + case OPERATOR_ANDEQ: + op = OPERATOR_AND; + break; + case OPERATOR_BITCLEAREQ: + op = OPERATOR_BITCLEAR; + break; + default: + gcc_unreachable(); + } + + Expression* binop = Expression::make_binary(op, lval, this->rhs_, loc); + Statement* s = Statement::make_assignment(this->lhs_, binop, loc); + if (b->statements()->empty()) + { + delete b; + return s; + } + else + { + b->add_statement(s); + return Statement::make_block_statement(b, loc); + } +} + +// Make an assignment operation statement. + +Statement* +Statement::make_assignment_operation(Operator op, Expression* lhs, + Expression* rhs, source_location location) +{ + return new Assignment_operation_statement(op, lhs, rhs, location); +} + +// A tuple assignment statement. This differs from an assignment +// statement in that the right-hand-side expressions are evaluated in +// parallel. + +class Tuple_assignment_statement : public Statement +{ + public: + Tuple_assignment_statement(Expression_list* lhs, Expression_list* rhs, + source_location location) + : Statement(STATEMENT_TUPLE_ASSIGNMENT, location), + lhs_(lhs), rhs_(rhs) + { } + + protected: + int + do_traverse(Traverse* traverse); + + bool + do_traverse_assignments(Traverse_assignments*) + { gcc_unreachable(); } + + Statement* + do_lower(Gogo*, Block*); + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + // Left hand side--a list of lvalues. + Expression_list* lhs_; + // Right hand side--a list of rvalues. + Expression_list* rhs_; +}; + +// Traversal. + +int +Tuple_assignment_statement::do_traverse(Traverse* traverse) +{ + if (this->traverse_expression_list(traverse, this->lhs_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return this->traverse_expression_list(traverse, this->rhs_); +} + +// Lower a tuple assignment. We use temporary variables to split it +// up into a set of single assignments. + +Statement* +Tuple_assignment_statement::do_lower(Gogo*, Block* enclosing) +{ + source_location loc = this->location(); + + Block* b = new Block(enclosing, loc); + + // First move out any subexpressions on the left hand side. The + // right hand side will be evaluated in the required order anyhow. + Move_ordered_evals moe(b); + for (Expression_list::const_iterator plhs = this->lhs_->begin(); + plhs != this->lhs_->end(); + ++plhs) + (*plhs)->traverse_subexpressions(&moe); + + std::vector<Temporary_statement*> temps; + temps.reserve(this->lhs_->size()); + + Expression_list::const_iterator prhs = this->rhs_->begin(); + for (Expression_list::const_iterator plhs = this->lhs_->begin(); + plhs != this->lhs_->end(); + ++plhs, ++prhs) + { + gcc_assert(prhs != this->rhs_->end()); + + if ((*plhs)->is_error_expression() + || (*plhs)->type()->is_error_type() + || (*prhs)->is_error_expression() + || (*prhs)->type()->is_error_type()) + continue; + + if ((*plhs)->is_sink_expression()) + { + b->add_statement(Statement::make_statement(*prhs)); + continue; + } + + Temporary_statement* temp = Statement::make_temporary((*plhs)->type(), + *prhs, loc); + b->add_statement(temp); + temps.push_back(temp); + + } + gcc_assert(prhs == this->rhs_->end()); + + prhs = this->rhs_->begin(); + std::vector<Temporary_statement*>::const_iterator ptemp = temps.begin(); + for (Expression_list::const_iterator plhs = this->lhs_->begin(); + plhs != this->lhs_->end(); + ++plhs, ++prhs) + { + if ((*plhs)->is_error_expression() + || (*plhs)->type()->is_error_type() + || (*prhs)->is_error_expression() + || (*prhs)->type()->is_error_type()) + continue; + + if ((*plhs)->is_sink_expression()) + continue; + + Expression* ref = Expression::make_temporary_reference(*ptemp, loc); + Statement* s = Statement::make_assignment(*plhs, ref, loc); + b->add_statement(s); + ++ptemp; + } + gcc_assert(ptemp == temps.end()); + + return Statement::make_block_statement(b, loc); +} + +// Make a tuple assignment statement. + +Statement* +Statement::make_tuple_assignment(Expression_list* lhs, Expression_list* rhs, + source_location location) +{ + return new Tuple_assignment_statement(lhs, rhs, location); +} + +// A tuple assignment from a map index expression. +// v, ok = m[k] + +class Tuple_map_assignment_statement : public Statement +{ +public: + Tuple_map_assignment_statement(Expression* val, Expression* present, + Expression* map_index, + source_location location) + : Statement(STATEMENT_TUPLE_MAP_ASSIGNMENT, location), + val_(val), present_(present), map_index_(map_index) + { } + + protected: + int + do_traverse(Traverse* traverse); + + bool + do_traverse_assignments(Traverse_assignments*) + { gcc_unreachable(); } + + Statement* + do_lower(Gogo*, Block*); + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + // Lvalue which receives the value from the map. + Expression* val_; + // Lvalue which receives whether the key value was present. + Expression* present_; + // The map index expression. + Expression* map_index_; +}; + +// Traversal. + +int +Tuple_map_assignment_statement::do_traverse(Traverse* traverse) +{ + if (this->traverse_expression(traverse, &this->val_) == TRAVERSE_EXIT + || this->traverse_expression(traverse, &this->present_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return this->traverse_expression(traverse, &this->map_index_); +} + +// Lower a tuple map assignment. + +Statement* +Tuple_map_assignment_statement::do_lower(Gogo*, Block* enclosing) +{ + source_location loc = this->location(); + + Map_index_expression* map_index = this->map_index_->map_index_expression(); + if (map_index == NULL) + { + this->report_error(_("expected map index on right hand side")); + return Statement::make_error_statement(loc); + } + Map_type* map_type = map_index->get_map_type(); + if (map_type == NULL) + return Statement::make_error_statement(loc); + + Block* b = new Block(enclosing, loc); + + // Move out any subexpressions to make sure that functions are + // called in the required order. + Move_ordered_evals moe(b); + this->val_->traverse_subexpressions(&moe); + this->present_->traverse_subexpressions(&moe); + + // Copy the key value into a temporary so that we can take its + // address without pushing the value onto the heap. + + // var key_temp KEY_TYPE = MAP_INDEX + Temporary_statement* key_temp = + Statement::make_temporary(map_type->key_type(), map_index->index(), loc); + b->add_statement(key_temp); + + // var val_temp VAL_TYPE + Temporary_statement* val_temp = + Statement::make_temporary(map_type->val_type(), NULL, loc); + b->add_statement(val_temp); + + // var present_temp bool + Temporary_statement* present_temp = + Statement::make_temporary(Type::lookup_bool_type(), NULL, loc); + b->add_statement(present_temp); + + // func mapaccess2(hmap map[k]v, key *k, val *v) bool + source_location bloc = BUILTINS_LOCATION; + Typed_identifier_list* param_types = new Typed_identifier_list(); + param_types->push_back(Typed_identifier("hmap", map_type, bloc)); + Type* pkey_type = Type::make_pointer_type(map_type->key_type()); + param_types->push_back(Typed_identifier("key", pkey_type, bloc)); + Type* pval_type = Type::make_pointer_type(map_type->val_type()); + param_types->push_back(Typed_identifier("val", pval_type, bloc)); + + Typed_identifier_list* ret_types = new Typed_identifier_list(); + ret_types->push_back(Typed_identifier("", Type::lookup_bool_type(), bloc)); + + Function_type* fntype = Type::make_function_type(NULL, param_types, + ret_types, bloc); + Named_object* mapaccess2 = + Named_object::make_function_declaration("mapaccess2", NULL, fntype, bloc); + mapaccess2->func_declaration_value()->set_asm_name("runtime.mapaccess2"); + + // present_temp = mapaccess2(MAP, &key_temp, &val_temp) + Expression* func = Expression::make_func_reference(mapaccess2, NULL, loc); + Expression_list* params = new Expression_list(); + params->push_back(map_index->map()); + Expression* ref = Expression::make_temporary_reference(key_temp, loc); + params->push_back(Expression::make_unary(OPERATOR_AND, ref, loc)); + ref = Expression::make_temporary_reference(val_temp, loc); + params->push_back(Expression::make_unary(OPERATOR_AND, ref, loc)); + Expression* call = Expression::make_call(func, params, false, loc); + + ref = Expression::make_temporary_reference(present_temp, loc); + Statement* s = Statement::make_assignment(ref, call, loc); + b->add_statement(s); + + // val = val_temp + ref = Expression::make_temporary_reference(val_temp, loc); + s = Statement::make_assignment(this->val_, ref, loc); + b->add_statement(s); + + // present = present_temp + ref = Expression::make_temporary_reference(present_temp, loc); + s = Statement::make_assignment(this->present_, ref, loc); + b->add_statement(s); + + return Statement::make_block_statement(b, loc); +} + +// Make a map assignment statement which returns a pair of values. + +Statement* +Statement::make_tuple_map_assignment(Expression* val, Expression* present, + Expression* map_index, + source_location location) +{ + return new Tuple_map_assignment_statement(val, present, map_index, location); +} + +// Assign a pair of entries to a map. +// m[k] = v, p + +class Map_assignment_statement : public Statement +{ + public: + Map_assignment_statement(Expression* map_index, + Expression* val, Expression* should_set, + source_location location) + : Statement(STATEMENT_MAP_ASSIGNMENT, location), + map_index_(map_index), val_(val), should_set_(should_set) + { } + + protected: + int + do_traverse(Traverse* traverse); + + bool + do_traverse_assignments(Traverse_assignments*) + { gcc_unreachable(); } + + Statement* + do_lower(Gogo*, Block*); + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + // A reference to the map index which should be set or deleted. + Expression* map_index_; + // The value to add to the map. + Expression* val_; + // Whether or not to add the value. + Expression* should_set_; +}; + +// Traverse a map assignment. + +int +Map_assignment_statement::do_traverse(Traverse* traverse) +{ + if (this->traverse_expression(traverse, &this->map_index_) == TRAVERSE_EXIT + || this->traverse_expression(traverse, &this->val_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return this->traverse_expression(traverse, &this->should_set_); +} + +// Lower a map assignment to a function call. + +Statement* +Map_assignment_statement::do_lower(Gogo*, Block* enclosing) +{ + source_location loc = this->location(); + + Map_index_expression* map_index = this->map_index_->map_index_expression(); + if (map_index == NULL) + { + this->report_error(_("expected map index on left hand side")); + return Statement::make_error_statement(loc); + } + Map_type* map_type = map_index->get_map_type(); + if (map_type == NULL) + return Statement::make_error_statement(loc); + + Block* b = new Block(enclosing, loc); + + // Evaluate the map first to get order of evaluation right. + // map_temp := m // we are evaluating m[k] = v, p + Temporary_statement* map_temp = Statement::make_temporary(map_type, + map_index->map(), + loc); + b->add_statement(map_temp); + + // var key_temp MAP_KEY_TYPE = k + Temporary_statement* key_temp = + Statement::make_temporary(map_type->key_type(), map_index->index(), loc); + b->add_statement(key_temp); + + // var val_temp MAP_VAL_TYPE = v + Temporary_statement* val_temp = + Statement::make_temporary(map_type->val_type(), this->val_, loc); + b->add_statement(val_temp); + + // func mapassign2(hmap map[k]v, key *k, val *v, p) + source_location bloc = BUILTINS_LOCATION; + Typed_identifier_list* param_types = new Typed_identifier_list(); + param_types->push_back(Typed_identifier("hmap", map_type, bloc)); + Type* pkey_type = Type::make_pointer_type(map_type->key_type()); + param_types->push_back(Typed_identifier("key", pkey_type, bloc)); + Type* pval_type = Type::make_pointer_type(map_type->val_type()); + param_types->push_back(Typed_identifier("val", pval_type, bloc)); + param_types->push_back(Typed_identifier("p", Type::lookup_bool_type(), bloc)); + Function_type* fntype = Type::make_function_type(NULL, param_types, + NULL, bloc); + Named_object* mapassign2 = + Named_object::make_function_declaration("mapassign2", NULL, fntype, bloc); + mapassign2->func_declaration_value()->set_asm_name("runtime.mapassign2"); + + // mapassign2(map_temp, &key_temp, &val_temp, p) + Expression* func = Expression::make_func_reference(mapassign2, NULL, loc); + Expression_list* params = new Expression_list(); + params->push_back(Expression::make_temporary_reference(map_temp, loc)); + Expression* ref = Expression::make_temporary_reference(key_temp, loc); + params->push_back(Expression::make_unary(OPERATOR_AND, ref, loc)); + ref = Expression::make_temporary_reference(val_temp, loc); + params->push_back(Expression::make_unary(OPERATOR_AND, ref, loc)); + params->push_back(this->should_set_); + Expression* call = Expression::make_call(func, params, false, loc); + Statement* s = Statement::make_statement(call); + b->add_statement(s); + + return Statement::make_block_statement(b, loc); +} + +// Make a statement which assigns a pair of entries to a map. + +Statement* +Statement::make_map_assignment(Expression* map_index, + Expression* val, Expression* should_set, + source_location location) +{ + return new Map_assignment_statement(map_index, val, should_set, location); +} + +// A tuple assignment from a receive statement. + +class Tuple_receive_assignment_statement : public Statement +{ + public: + Tuple_receive_assignment_statement(Expression* val, Expression* success, + Expression* channel, + source_location location) + : Statement(STATEMENT_TUPLE_RECEIVE_ASSIGNMENT, location), + val_(val), success_(success), channel_(channel) + { } + + protected: + int + do_traverse(Traverse* traverse); + + bool + do_traverse_assignments(Traverse_assignments*) + { gcc_unreachable(); } + + Statement* + do_lower(Gogo*, Block*); + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + // Lvalue which receives the value from the channel. + Expression* val_; + // Lvalue which receives whether the read succeeded or failed. + Expression* success_; + // The channel on which we receive the value. + Expression* channel_; +}; + +// Traversal. + +int +Tuple_receive_assignment_statement::do_traverse(Traverse* traverse) +{ + if (this->traverse_expression(traverse, &this->val_) == TRAVERSE_EXIT + || this->traverse_expression(traverse, &this->success_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return this->traverse_expression(traverse, &this->channel_); +} + +// Lower to a function call. + +Statement* +Tuple_receive_assignment_statement::do_lower(Gogo*, Block* enclosing) +{ + source_location loc = this->location(); + + Channel_type* channel_type = this->channel_->type()->channel_type(); + if (channel_type == NULL) + { + this->report_error(_("expected channel")); + return Statement::make_error_statement(loc); + } + if (!channel_type->may_receive()) + { + this->report_error(_("invalid receive on send-only channel")); + return Statement::make_error_statement(loc); + } + + Block* b = new Block(enclosing, loc); + + // Make sure that any subexpressions on the left hand side are + // evaluated in the right order. + Move_ordered_evals moe(b); + this->val_->traverse_subexpressions(&moe); + this->success_->traverse_subexpressions(&moe); + + // var val_temp ELEMENT_TYPE + Temporary_statement* val_temp = + Statement::make_temporary(channel_type->element_type(), NULL, loc); + b->add_statement(val_temp); + + // var success_temp bool + Temporary_statement* success_temp = + Statement::make_temporary(Type::lookup_bool_type(), NULL, loc); + b->add_statement(success_temp); + + // func chanrecv2(c chan T, val *T) bool + source_location bloc = BUILTINS_LOCATION; + Typed_identifier_list* param_types = new Typed_identifier_list(); + param_types->push_back(Typed_identifier("c", channel_type, bloc)); + Type* pelement_type = Type::make_pointer_type(channel_type->element_type()); + param_types->push_back(Typed_identifier("val", pelement_type, bloc)); + + Typed_identifier_list* ret_types = new Typed_identifier_list(); + ret_types->push_back(Typed_identifier("", Type::lookup_bool_type(), bloc)); + + Function_type* fntype = Type::make_function_type(NULL, param_types, + ret_types, bloc); + Named_object* chanrecv2 = + Named_object::make_function_declaration("chanrecv2", NULL, fntype, bloc); + chanrecv2->func_declaration_value()->set_asm_name("runtime.chanrecv2"); + + // success_temp = chanrecv2(channel, &val_temp) + Expression* func = Expression::make_func_reference(chanrecv2, NULL, loc); + Expression_list* params = new Expression_list(); + params->push_back(this->channel_); + Expression* ref = Expression::make_temporary_reference(val_temp, loc); + params->push_back(Expression::make_unary(OPERATOR_AND, ref, loc)); + Expression* call = Expression::make_call(func, params, false, loc); + ref = Expression::make_temporary_reference(success_temp, loc); + Statement* s = Statement::make_assignment(ref, call, loc); + b->add_statement(s); + + // val = val_temp + ref = Expression::make_temporary_reference(val_temp, loc); + s = Statement::make_assignment(this->val_, ref, loc); + b->add_statement(s); + + // success = success_temp + ref = Expression::make_temporary_reference(success_temp, loc); + s = Statement::make_assignment(this->success_, ref, loc); + b->add_statement(s); + + return Statement::make_block_statement(b, loc); +} + +// Make a nonblocking receive statement. + +Statement* +Statement::make_tuple_receive_assignment(Expression* val, Expression* success, + Expression* channel, + source_location location) +{ + return new Tuple_receive_assignment_statement(val, success, channel, + location); +} + +// An assignment to a pair of values from a type guard. This is a +// conditional type guard. v, ok = i.(type). + +class Tuple_type_guard_assignment_statement : public Statement +{ + public: + Tuple_type_guard_assignment_statement(Expression* val, Expression* ok, + Expression* expr, Type* type, + source_location location) + : Statement(STATEMENT_TUPLE_TYPE_GUARD_ASSIGNMENT, location), + val_(val), ok_(ok), expr_(expr), type_(type) + { } + + protected: + int + do_traverse(Traverse*); + + bool + do_traverse_assignments(Traverse_assignments*) + { gcc_unreachable(); } + + Statement* + do_lower(Gogo*, Block*); + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + Call_expression* + lower_to_empty_interface(const char*); + + Call_expression* + lower_to_type(const char*); + + void + lower_to_object_type(Block*, const char*); + + // The variable which recieves the converted value. + Expression* val_; + // The variable which receives the indication of success. + Expression* ok_; + // The expression being converted. + Expression* expr_; + // The type to which the expression is being converted. + Type* type_; +}; + +// Traverse a type guard tuple assignment. + +int +Tuple_type_guard_assignment_statement::do_traverse(Traverse* traverse) +{ + if (this->traverse_expression(traverse, &this->val_) == TRAVERSE_EXIT + || this->traverse_expression(traverse, &this->ok_) == TRAVERSE_EXIT + || this->traverse_type(traverse, this->type_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return this->traverse_expression(traverse, &this->expr_); +} + +// Lower to a function call. + +Statement* +Tuple_type_guard_assignment_statement::do_lower(Gogo*, Block* enclosing) +{ + source_location loc = this->location(); + + Type* expr_type = this->expr_->type(); + if (expr_type->interface_type() == NULL) + { + if (!expr_type->is_error_type() && !this->type_->is_error_type()) + this->report_error(_("type assertion only valid for interface types")); + return Statement::make_error_statement(loc); + } + + Block* b = new Block(enclosing, loc); + + // Make sure that any subexpressions on the left hand side are + // evaluated in the right order. + Move_ordered_evals moe(b); + this->val_->traverse_subexpressions(&moe); + this->ok_->traverse_subexpressions(&moe); + + bool expr_is_empty = expr_type->interface_type()->is_empty(); + Call_expression* call; + if (this->type_->interface_type() != NULL) + { + if (this->type_->interface_type()->is_empty()) + call = this->lower_to_empty_interface(expr_is_empty + ? "ifaceE2E2" + : "ifaceI2E2"); + else + call = this->lower_to_type(expr_is_empty ? "ifaceE2I2" : "ifaceI2I2"); + } + else if (this->type_->points_to() != NULL) + call = this->lower_to_type(expr_is_empty ? "ifaceE2T2P" : "ifaceI2T2P"); + else + { + this->lower_to_object_type(b, expr_is_empty ? "ifaceE2T2" : "ifaceI2T2"); + call = NULL; + } + + if (call != NULL) + { + Expression* res = Expression::make_call_result(call, 0); + Statement* s = Statement::make_assignment(this->val_, res, loc); + b->add_statement(s); + + res = Expression::make_call_result(call, 1); + s = Statement::make_assignment(this->ok_, res, loc); + b->add_statement(s); + } + + return Statement::make_block_statement(b, loc); +} + +// Lower a conversion to an empty interface type. + +Call_expression* +Tuple_type_guard_assignment_statement::lower_to_empty_interface( + const char *fnname) +{ + source_location loc = this->location(); + + // func FNNAME(interface) (empty, bool) + source_location bloc = BUILTINS_LOCATION; + Typed_identifier_list* param_types = new Typed_identifier_list(); + param_types->push_back(Typed_identifier("i", this->expr_->type(), bloc)); + Typed_identifier_list* ret_types = new Typed_identifier_list(); + ret_types->push_back(Typed_identifier("ret", this->type_, bloc)); + ret_types->push_back(Typed_identifier("ok", Type::lookup_bool_type(), bloc)); + Function_type* fntype = Type::make_function_type(NULL, param_types, + ret_types, bloc); + Named_object* fn = + Named_object::make_function_declaration(fnname, NULL, fntype, bloc); + std::string asm_name = "runtime."; + asm_name += fnname; + fn->func_declaration_value()->set_asm_name(asm_name); + + // val, ok = FNNAME(expr) + Expression* func = Expression::make_func_reference(fn, NULL, loc); + Expression_list* params = new Expression_list(); + params->push_back(this->expr_); + return Expression::make_call(func, params, false, loc); +} + +// Lower a conversion to a non-empty interface type or a pointer type. + +Call_expression* +Tuple_type_guard_assignment_statement::lower_to_type(const char* fnname) +{ + source_location loc = this->location(); + + // func FNNAME(*descriptor, interface) (interface, bool) + source_location bloc = BUILTINS_LOCATION; + Typed_identifier_list* param_types = new Typed_identifier_list(); + param_types->push_back(Typed_identifier("inter", + Type::make_type_descriptor_ptr_type(), + bloc)); + param_types->push_back(Typed_identifier("i", this->expr_->type(), bloc)); + Typed_identifier_list* ret_types = new Typed_identifier_list(); + ret_types->push_back(Typed_identifier("ret", this->type_, bloc)); + ret_types->push_back(Typed_identifier("ok", Type::lookup_bool_type(), bloc)); + Function_type* fntype = Type::make_function_type(NULL, param_types, + ret_types, bloc); + Named_object* fn = + Named_object::make_function_declaration(fnname, NULL, fntype, bloc); + std::string asm_name = "runtime."; + asm_name += fnname; + fn->func_declaration_value()->set_asm_name(asm_name); + + // val, ok = FNNAME(type_descriptor, expr) + Expression* func = Expression::make_func_reference(fn, NULL, loc); + Expression_list* params = new Expression_list(); + params->push_back(Expression::make_type_descriptor(this->type_, loc)); + params->push_back(this->expr_); + return Expression::make_call(func, params, false, loc); +} + +// Lower a conversion to a non-interface non-pointer type. + +void +Tuple_type_guard_assignment_statement::lower_to_object_type(Block* b, + const char *fnname) +{ + source_location loc = this->location(); + + // var val_temp TYPE + Temporary_statement* val_temp = Statement::make_temporary(this->type_, + NULL, loc); + b->add_statement(val_temp); + + // func FNNAME(*descriptor, interface, *T) bool + source_location bloc = BUILTINS_LOCATION; + Typed_identifier_list* param_types = new Typed_identifier_list(); + param_types->push_back(Typed_identifier("inter", + Type::make_type_descriptor_ptr_type(), + bloc)); + param_types->push_back(Typed_identifier("i", this->expr_->type(), bloc)); + Type* ptype = Type::make_pointer_type(this->type_); + param_types->push_back(Typed_identifier("v", ptype, bloc)); + Typed_identifier_list* ret_types = new Typed_identifier_list(); + ret_types->push_back(Typed_identifier("ok", Type::lookup_bool_type(), bloc)); + Function_type* fntype = Type::make_function_type(NULL, param_types, + ret_types, bloc); + Named_object* fn = + Named_object::make_function_declaration(fnname, NULL, fntype, bloc); + std::string asm_name = "runtime."; + asm_name += fnname; + fn->func_declaration_value()->set_asm_name(asm_name); + + // ok = FNNAME(type_descriptor, expr, &val_temp) + Expression* func = Expression::make_func_reference(fn, NULL, loc); + Expression_list* params = new Expression_list(); + params->push_back(Expression::make_type_descriptor(this->type_, loc)); + params->push_back(this->expr_); + Expression* ref = Expression::make_temporary_reference(val_temp, loc); + params->push_back(Expression::make_unary(OPERATOR_AND, ref, loc)); + Expression* call = Expression::make_call(func, params, false, loc); + Statement* s = Statement::make_assignment(this->ok_, call, loc); + b->add_statement(s); + + // val = val_temp + ref = Expression::make_temporary_reference(val_temp, loc); + s = Statement::make_assignment(this->val_, ref, loc); + b->add_statement(s); +} + +// Make an assignment from a type guard to a pair of variables. + +Statement* +Statement::make_tuple_type_guard_assignment(Expression* val, Expression* ok, + Expression* expr, Type* type, + source_location location) +{ + return new Tuple_type_guard_assignment_statement(val, ok, expr, type, + location); +} + +// An expression statement. + +class Expression_statement : public Statement +{ + public: + Expression_statement(Expression* expr) + : Statement(STATEMENT_EXPRESSION, expr->location()), + expr_(expr) + { } + + protected: + int + do_traverse(Traverse* traverse) + { return this->traverse_expression(traverse, &this->expr_); } + + void + do_determine_types() + { this->expr_->determine_type_no_context(); } + + bool + do_may_fall_through() const; + + tree + do_get_tree(Translate_context* context) + { return this->expr_->get_tree(context); } + + private: + Expression* expr_; +}; + +// An expression statement may fall through unless it is a call to a +// function which does not return. + +bool +Expression_statement::do_may_fall_through() const +{ + const Call_expression* call = this->expr_->call_expression(); + if (call != NULL) + { + const Expression* fn = call->fn(); + const Func_expression* fe = fn->func_expression(); + if (fe != NULL) + { + const Named_object* no = fe->named_object(); + + Function_type* fntype; + if (no->is_function()) + fntype = no->func_value()->type(); + else if (no->is_function_declaration()) + fntype = no->func_declaration_value()->type(); + else + fntype = NULL; + + // The builtin function panic does not return. + if (fntype != NULL && fntype->is_builtin() && no->name() == "panic") + return false; + } + } + return true; +} + +// Make an expression statement from an Expression. + +Statement* +Statement::make_statement(Expression* expr) +{ + return new Expression_statement(expr); +} + +// A block statement--a list of statements which may include variable +// definitions. + +class Block_statement : public Statement +{ + public: + Block_statement(Block* block, source_location location) + : Statement(STATEMENT_BLOCK, location), + block_(block) + { } + + protected: + int + do_traverse(Traverse* traverse) + { return this->block_->traverse(traverse); } + + void + do_determine_types() + { this->block_->determine_types(); } + + bool + do_may_fall_through() const + { return this->block_->may_fall_through(); } + + tree + do_get_tree(Translate_context* context) + { return this->block_->get_tree(context); } + + private: + Block* block_; +}; + +// Make a block statement. + +Statement* +Statement::make_block_statement(Block* block, source_location location) +{ + return new Block_statement(block, location); +} + +// An increment or decrement statement. + +class Inc_dec_statement : public Statement +{ + public: + Inc_dec_statement(bool is_inc, Expression* expr) + : Statement(STATEMENT_INCDEC, expr->location()), + expr_(expr), is_inc_(is_inc) + { } + + protected: + int + do_traverse(Traverse* traverse) + { return this->traverse_expression(traverse, &this->expr_); } + + bool + do_traverse_assignments(Traverse_assignments*) + { gcc_unreachable(); } + + Statement* + do_lower(Gogo*, Block*); + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + // The l-value to increment or decrement. + Expression* expr_; + // Whether to increment or decrement. + bool is_inc_; +}; + +// Lower to += or -=. + +Statement* +Inc_dec_statement::do_lower(Gogo*, Block*) +{ + source_location loc = this->location(); + + mpz_t oval; + mpz_init_set_ui(oval, 1UL); + Expression* oexpr = Expression::make_integer(&oval, NULL, loc); + mpz_clear(oval); + + Operator op = this->is_inc_ ? OPERATOR_PLUSEQ : OPERATOR_MINUSEQ; + return Statement::make_assignment_operation(op, this->expr_, oexpr, loc); +} + +// Make an increment statement. + +Statement* +Statement::make_inc_statement(Expression* expr) +{ + return new Inc_dec_statement(true, expr); +} + +// Make a decrement statement. + +Statement* +Statement::make_dec_statement(Expression* expr) +{ + return new Inc_dec_statement(false, expr); +} + +// Class Thunk_statement. This is the base class for go and defer +// statements. + +const char* const Thunk_statement::thunk_field_fn = "fn"; + +const char* const Thunk_statement::thunk_field_receiver = "receiver"; + +// Constructor. + +Thunk_statement::Thunk_statement(Statement_classification classification, + Call_expression* call, + source_location location) + : Statement(classification, location), + call_(call), struct_type_(NULL) +{ +} + +// Return whether this is a simple statement which does not require a +// thunk. + +bool +Thunk_statement::is_simple(Function_type* fntype) const +{ + // We need a thunk to call a method, or to pass a variable number of + // arguments. + if (fntype->is_method() || fntype->is_varargs()) + return false; + + // A defer statement requires a thunk to set up for whether the + // function can call recover. + if (this->classification() == STATEMENT_DEFER) + return false; + + // We can only permit a single parameter of pointer type. + const Typed_identifier_list* parameters = fntype->parameters(); + if (parameters != NULL + && (parameters->size() > 1 + || (parameters->size() == 1 + && parameters->begin()->type()->points_to() == NULL))) + return false; + + // If the function returns multiple values, or returns a type other + // than integer, floating point, or pointer, then it may get a + // hidden first parameter, in which case we need the more + // complicated approach. This is true even though we are going to + // ignore the return value. + const Typed_identifier_list* results = fntype->results(); + if (results != NULL + && (results->size() > 1 + || (results->size() == 1 + && !results->begin()->type()->is_basic_type() + && results->begin()->type()->points_to() == NULL))) + return false; + + // If this calls something which is not a simple function, then we + // need a thunk. + Expression* fn = this->call_->call_expression()->fn(); + if (fn->bound_method_expression() != NULL + || fn->interface_field_reference_expression() != NULL) + return false; + + return true; +} + +// Traverse a thunk statement. + +int +Thunk_statement::do_traverse(Traverse* traverse) +{ + return this->traverse_expression(traverse, &this->call_); +} + +// We implement traverse_assignment for a thunk statement because it +// effectively copies the function call. + +bool +Thunk_statement::do_traverse_assignments(Traverse_assignments* tassign) +{ + Expression* fn = this->call_->call_expression()->fn(); + Expression* fn2 = fn; + tassign->value(&fn2, true, false); + return true; +} + +// Determine types in a thunk statement. + +void +Thunk_statement::do_determine_types() +{ + this->call_->determine_type_no_context(); + + // Now that we know the types of the call, build the struct used to + // pass parameters. + Call_expression* ce = this->call_->call_expression(); + if (ce == NULL) + return; + Function_type* fntype = ce->get_function_type(); + if (fntype != NULL && !this->is_simple(fntype)) + this->struct_type_ = this->build_struct(fntype); +} + +// Check types in a thunk statement. + +void +Thunk_statement::do_check_types(Gogo*) +{ + Call_expression* ce = this->call_->call_expression(); + if (ce == NULL) + { + if (!this->call_->is_error_expression()) + this->report_error("expected call expression"); + return; + } + Function_type* fntype = ce->get_function_type(); + if (fntype != NULL && fntype->is_method()) + { + Expression* fn = ce->fn(); + if (fn->bound_method_expression() == NULL + && fn->interface_field_reference_expression() == NULL) + this->report_error(_("no object for method call")); + } +} + +// The Traverse class used to find and simplify thunk statements. + +class Simplify_thunk_traverse : public Traverse +{ + public: + Simplify_thunk_traverse(Gogo* gogo) + : Traverse(traverse_blocks), + gogo_(gogo) + { } + + int + block(Block*); + + private: + Gogo* gogo_; +}; + +int +Simplify_thunk_traverse::block(Block* b) +{ + // The parser ensures that thunk statements always appear at the end + // of a block. + if (b->statements()->size() < 1) + return TRAVERSE_CONTINUE; + Thunk_statement* stat = b->statements()->back()->thunk_statement(); + if (stat == NULL) + return TRAVERSE_CONTINUE; + if (stat->simplify_statement(this->gogo_, b)) + return TRAVERSE_SKIP_COMPONENTS; + return TRAVERSE_CONTINUE; +} + +// Simplify all thunk statements. + +void +Gogo::simplify_thunk_statements() +{ + Simplify_thunk_traverse thunk_traverse(this); + this->traverse(&thunk_traverse); +} + +// Simplify complex thunk statements into simple ones. A complicated +// thunk statement is one which takes anything other than zero +// parameters or a single pointer parameter. We rewrite it into code +// which allocates a struct, stores the parameter values into the +// struct, and does a simple go or defer statement which passes the +// struct to a thunk. The thunk does the real call. + +bool +Thunk_statement::simplify_statement(Gogo* gogo, Block* block) +{ + if (this->classification() == STATEMENT_ERROR) + return false; + if (this->call_->is_error_expression()) + return false; + + Call_expression* ce = this->call_->call_expression(); + Function_type* fntype = ce->get_function_type(); + if (fntype == NULL) + { + gcc_assert(saw_errors()); + this->set_is_error(); + return false; + } + if (this->is_simple(fntype)) + return false; + + Expression* fn = ce->fn(); + Bound_method_expression* bound_method = fn->bound_method_expression(); + Interface_field_reference_expression* interface_method = + fn->interface_field_reference_expression(); + const bool is_method = bound_method != NULL || interface_method != NULL; + + source_location location = this->location(); + + std::string thunk_name = Gogo::thunk_name(); + + // Build the thunk. + this->build_thunk(gogo, thunk_name, fntype); + + // Generate code to call the thunk. + + // Get the values to store into the struct which is the single + // argument to the thunk. + + Expression_list* vals = new Expression_list(); + if (fntype->is_builtin()) + ; + else if (!is_method) + vals->push_back(fn); + else if (interface_method != NULL) + vals->push_back(interface_method->expr()); + else if (bound_method != NULL) + { + vals->push_back(bound_method->method()); + Expression* first_arg = bound_method->first_argument(); + + // We always pass a pointer when calling a method. + if (first_arg->type()->points_to() == NULL) + first_arg = Expression::make_unary(OPERATOR_AND, first_arg, location); + + // If we are calling a method which was inherited from an + // embedded struct, and the method did not get a stub, then the + // first type may be wrong. + Type* fatype = bound_method->first_argument_type(); + if (fatype != NULL) + { + if (fatype->points_to() == NULL) + fatype = Type::make_pointer_type(fatype); + Type* unsafe = Type::make_pointer_type(Type::make_void_type()); + first_arg = Expression::make_cast(unsafe, first_arg, location); + first_arg = Expression::make_cast(fatype, first_arg, location); + } + + vals->push_back(first_arg); + } + else + gcc_unreachable(); + + if (ce->args() != NULL) + { + for (Expression_list::const_iterator p = ce->args()->begin(); + p != ce->args()->end(); + ++p) + vals->push_back(*p); + } + + // Build the struct. + Expression* constructor = + Expression::make_struct_composite_literal(this->struct_type_, vals, + location); + + // Allocate the initialized struct on the heap. + constructor = Expression::make_heap_composite(constructor, location); + + // Look up the thunk. + Named_object* named_thunk = gogo->lookup(thunk_name, NULL); + gcc_assert(named_thunk != NULL && named_thunk->is_function()); + + // Build the call. + Expression* func = Expression::make_func_reference(named_thunk, NULL, + location); + Expression_list* params = new Expression_list(); + params->push_back(constructor); + Call_expression* call = Expression::make_call(func, params, false, location); + + // Build the simple go or defer statement. + Statement* s; + if (this->classification() == STATEMENT_GO) + s = Statement::make_go_statement(call, location); + else if (this->classification() == STATEMENT_DEFER) + s = Statement::make_defer_statement(call, location); + else + gcc_unreachable(); + + // The current block should end with the go statement. + gcc_assert(block->statements()->size() >= 1); + gcc_assert(block->statements()->back() == this); + block->replace_statement(block->statements()->size() - 1, s); + + // We already ran the determine_types pass, so we need to run it now + // for the new statement. + s->determine_types(); + + // Sanity check. + gogo->check_types_in_block(block); + + // Return true to tell the block not to keep looking at statements. + return true; +} + +// Set the name to use for thunk parameter N. + +void +Thunk_statement::thunk_field_param(int n, char* buf, size_t buflen) +{ + snprintf(buf, buflen, "a%d", n); +} + +// Build a new struct type to hold the parameters for a complicated +// thunk statement. FNTYPE is the type of the function call. + +Struct_type* +Thunk_statement::build_struct(Function_type* fntype) +{ + source_location location = this->location(); + + Struct_field_list* fields = new Struct_field_list(); + + Call_expression* ce = this->call_->call_expression(); + Expression* fn = ce->fn(); + + Interface_field_reference_expression* interface_method = + fn->interface_field_reference_expression(); + if (interface_method != NULL) + { + // If this thunk statement calls a method on an interface, we + // pass the interface object to the thunk. + Typed_identifier tid(Thunk_statement::thunk_field_fn, + interface_method->expr()->type(), + location); + fields->push_back(Struct_field(tid)); + } + else if (!fntype->is_builtin()) + { + // The function to call. + Typed_identifier tid(Go_statement::thunk_field_fn, fntype, location); + fields->push_back(Struct_field(tid)); + } + else if (ce->is_recover_call()) + { + // The predeclared recover function has no argument. However, + // we add an argument when building recover thunks. Handle that + // here. + fields->push_back(Struct_field(Typed_identifier("can_recover", + Type::lookup_bool_type(), + location))); + } + + if (fn->bound_method_expression() != NULL) + { + gcc_assert(fntype->is_method()); + Type* rtype = fntype->receiver()->type(); + // We always pass the receiver as a pointer. + if (rtype->points_to() == NULL) + rtype = Type::make_pointer_type(rtype); + Typed_identifier tid(Thunk_statement::thunk_field_receiver, rtype, + location); + fields->push_back(Struct_field(tid)); + } + + const Expression_list* args = ce->args(); + if (args != NULL) + { + int i = 0; + for (Expression_list::const_iterator p = args->begin(); + p != args->end(); + ++p, ++i) + { + char buf[50]; + this->thunk_field_param(i, buf, sizeof buf); + fields->push_back(Struct_field(Typed_identifier(buf, (*p)->type(), + location))); + } + } + + return Type::make_struct_type(fields, location); +} + +// Build the thunk we are going to call. This is a brand new, albeit +// artificial, function. + +void +Thunk_statement::build_thunk(Gogo* gogo, const std::string& thunk_name, + Function_type* fntype) +{ + source_location location = this->location(); + + Call_expression* ce = this->call_->call_expression(); + + bool may_call_recover = false; + if (this->classification() == STATEMENT_DEFER) + { + Func_expression* fn = ce->fn()->func_expression(); + if (fn == NULL) + may_call_recover = true; + else + { + const Named_object* no = fn->named_object(); + if (!no->is_function()) + may_call_recover = true; + else + may_call_recover = no->func_value()->calls_recover(); + } + } + + // Build the type of the thunk. The thunk takes a single parameter, + // which is a pointer to the special structure we build. + const char* const parameter_name = "__go_thunk_parameter"; + Typed_identifier_list* thunk_parameters = new Typed_identifier_list(); + Type* pointer_to_struct_type = Type::make_pointer_type(this->struct_type_); + thunk_parameters->push_back(Typed_identifier(parameter_name, + pointer_to_struct_type, + location)); + + Typed_identifier_list* thunk_results = NULL; + if (may_call_recover) + { + // When deferring a function which may call recover, add a + // return value, to disable tail call optimizations which will + // break the way we check whether recover is permitted. + thunk_results = new Typed_identifier_list(); + thunk_results->push_back(Typed_identifier("", Type::lookup_bool_type(), + location)); + } + + Function_type* thunk_type = Type::make_function_type(NULL, thunk_parameters, + thunk_results, + location); + + // Start building the thunk. + Named_object* function = gogo->start_function(thunk_name, thunk_type, true, + location); + + // For a defer statement, start with a call to + // __go_set_defer_retaddr. */ + Label* retaddr_label = NULL; + if (may_call_recover) + { + retaddr_label = gogo->add_label_reference("retaddr"); + Expression* arg = Expression::make_label_addr(retaddr_label, location); + Expression_list* args = new Expression_list(); + args->push_back(arg); + + static Named_object* set_defer_retaddr; + if (set_defer_retaddr == NULL) + { + const source_location bloc = BUILTINS_LOCATION; + Typed_identifier_list* param_types = new Typed_identifier_list(); + Type *voidptr_type = Type::make_pointer_type(Type::make_void_type()); + param_types->push_back(Typed_identifier("r", voidptr_type, bloc)); + + Typed_identifier_list* result_types = new Typed_identifier_list(); + result_types->push_back(Typed_identifier("", + Type::lookup_bool_type(), + bloc)); + + Function_type* t = Type::make_function_type(NULL, param_types, + result_types, bloc); + set_defer_retaddr = + Named_object::make_function_declaration("__go_set_defer_retaddr", + NULL, t, bloc); + const char* n = "__go_set_defer_retaddr"; + set_defer_retaddr->func_declaration_value()->set_asm_name(n); + } + + Expression* fn = Expression::make_func_reference(set_defer_retaddr, + NULL, location); + Expression* call = Expression::make_call(fn, args, false, location); + + // This is a hack to prevent the middle-end from deleting the + // label. + gogo->start_block(location); + gogo->add_statement(Statement::make_goto_statement(retaddr_label, + location)); + Block* then_block = gogo->finish_block(location); + then_block->determine_types(); + + Statement* s = Statement::make_if_statement(call, then_block, NULL, + location); + s->determine_types(); + gogo->add_statement(s); + } + + // Get a reference to the parameter. + Named_object* named_parameter = gogo->lookup(parameter_name, NULL); + gcc_assert(named_parameter != NULL && named_parameter->is_variable()); + + // Build the call. Note that the field names are the same as the + // ones used in build_struct. + Expression* thunk_parameter = Expression::make_var_reference(named_parameter, + location); + thunk_parameter = Expression::make_unary(OPERATOR_MULT, thunk_parameter, + location); + + Bound_method_expression* bound_method = ce->fn()->bound_method_expression(); + Interface_field_reference_expression* interface_method = + ce->fn()->interface_field_reference_expression(); + + Expression* func_to_call; + unsigned int next_index; + if (!fntype->is_builtin()) + { + func_to_call = Expression::make_field_reference(thunk_parameter, + 0, location); + next_index = 1; + } + else + { + gcc_assert(bound_method == NULL && interface_method == NULL); + func_to_call = ce->fn(); + next_index = 0; + } + + if (bound_method != NULL) + { + Expression* r = Expression::make_field_reference(thunk_parameter, 1, + location); + // The main program passes in a function pointer from the + // interface expression, so here we can make a bound method in + // all cases. + func_to_call = Expression::make_bound_method(r, func_to_call, + location); + next_index = 2; + } + else if (interface_method != NULL) + { + // The main program passes the interface object. + const std::string& name(interface_method->name()); + func_to_call = Expression::make_interface_field_reference(func_to_call, + name, + location); + } + + Expression_list* call_params = new Expression_list(); + const Struct_field_list* fields = this->struct_type_->fields(); + Struct_field_list::const_iterator p = fields->begin(); + for (unsigned int i = 0; i < next_index; ++i) + ++p; + bool is_recover_call = ce->is_recover_call(); + Expression* recover_arg = NULL; + for (; p != fields->end(); ++p, ++next_index) + { + Expression* thunk_param = Expression::make_var_reference(named_parameter, + location); + thunk_param = Expression::make_unary(OPERATOR_MULT, thunk_param, + location); + Expression* param = Expression::make_field_reference(thunk_param, + next_index, + location); + if (!is_recover_call) + call_params->push_back(param); + else + { + gcc_assert(call_params->empty()); + recover_arg = param; + } + } + + if (call_params->empty()) + { + delete call_params; + call_params = NULL; + } + + Expression* call = Expression::make_call(func_to_call, call_params, false, + location); + // We need to lower in case this is a builtin function. + call = call->lower(gogo, function, -1); + Call_expression* call_ce = call->call_expression(); + if (call_ce != NULL && may_call_recover) + call_ce->set_is_deferred(); + + Statement* call_statement = Statement::make_statement(call); + + // We already ran the determine_types pass, so we need to run it + // just for this statement now. + call_statement->determine_types(); + + // Sanity check. + call->check_types(gogo); + + if (call_ce != NULL && recover_arg != NULL) + call_ce->set_recover_arg(recover_arg); + + gogo->add_statement(call_statement); + + // If this is a defer statement, the label comes immediately after + // the call. + if (may_call_recover) + { + gogo->add_label_definition("retaddr", location); + + Expression_list* vals = new Expression_list(); + vals->push_back(Expression::make_boolean(false, location)); + const Typed_identifier_list* results = + function->func_value()->type()->results(); + gogo->add_statement(Statement::make_return_statement(results, vals, + location)); + } + + // That is all the thunk has to do. + gogo->finish_function(location); +} + +// Get the function and argument trees. + +void +Thunk_statement::get_fn_and_arg(Translate_context* context, tree* pfn, + tree* parg) +{ + if (this->call_->is_error_expression()) + { + *pfn = error_mark_node; + *parg = error_mark_node; + return; + } + + Call_expression* ce = this->call_->call_expression(); + + Expression* fn = ce->fn(); + *pfn = fn->get_tree(context); + + const Expression_list* args = ce->args(); + if (args == NULL || args->empty()) + *parg = null_pointer_node; + else + { + gcc_assert(args->size() == 1); + *parg = args->front()->get_tree(context); + } +} + +// Class Go_statement. + +tree +Go_statement::do_get_tree(Translate_context* context) +{ + tree fn_tree; + tree arg_tree; + this->get_fn_and_arg(context, &fn_tree, &arg_tree); + + static tree go_fndecl; + + tree fn_arg_type = NULL_TREE; + if (go_fndecl == NULL_TREE) + { + // Only build FN_ARG_TYPE if we need it. + tree subargtypes = tree_cons(NULL_TREE, ptr_type_node, void_list_node); + tree subfntype = build_function_type(ptr_type_node, subargtypes); + fn_arg_type = build_pointer_type(subfntype); + } + + return Gogo::call_builtin(&go_fndecl, + this->location(), + "__go_go", + 2, + void_type_node, + fn_arg_type, + fn_tree, + ptr_type_node, + arg_tree); +} + +// Make a go statement. + +Statement* +Statement::make_go_statement(Call_expression* call, source_location location) +{ + return new Go_statement(call, location); +} + +// Class Defer_statement. + +tree +Defer_statement::do_get_tree(Translate_context* context) +{ + source_location loc = this->location(); + + tree fn_tree; + tree arg_tree; + this->get_fn_and_arg(context, &fn_tree, &arg_tree); + if (fn_tree == error_mark_node || arg_tree == error_mark_node) + return error_mark_node; + + static tree defer_fndecl; + + tree fn_arg_type = NULL_TREE; + if (defer_fndecl == NULL_TREE) + { + // Only build FN_ARG_TYPE if we need it. + tree subargtypes = tree_cons(NULL_TREE, ptr_type_node, void_list_node); + tree subfntype = build_function_type(ptr_type_node, subargtypes); + fn_arg_type = build_pointer_type(subfntype); + } + + tree defer_stack = context->function()->func_value()->defer_stack(loc); + + return Gogo::call_builtin(&defer_fndecl, + loc, + "__go_defer", + 3, + void_type_node, + ptr_type_node, + defer_stack, + fn_arg_type, + fn_tree, + ptr_type_node, + arg_tree); +} + +// Make a defer statement. + +Statement* +Statement::make_defer_statement(Call_expression* call, + source_location location) +{ + return new Defer_statement(call, location); +} + +// Class Return_statement. + +// Traverse assignments. We treat each return value as a top level +// RHS in an expression. + +bool +Return_statement::do_traverse_assignments(Traverse_assignments* tassign) +{ + Expression_list* vals = this->vals_; + if (vals != NULL) + { + for (Expression_list::iterator p = vals->begin(); + p != vals->end(); + ++p) + tassign->value(&*p, true, true); + } + return true; +} + +// Lower a return statement. If we are returning a function call +// which returns multiple values which match the current function, +// split up the call's results. If the function has named result +// variables, and the return statement lists explicit values, then +// implement it by assigning the values to the result variables and +// changing the statement to not list any values. This lets +// panic/recover work correctly. + +Statement* +Return_statement::do_lower(Gogo*, Block* enclosing) +{ + if (this->vals_ == NULL) + return this; + + const Typed_identifier_list* results = this->results_; + if (results == NULL || results->empty()) + return this; + + // If the current function has multiple return values, and we are + // returning a single call expression, split up the call expression. + size_t results_count = results->size(); + if (results_count > 1 + && this->vals_->size() == 1 + && this->vals_->front()->call_expression() != NULL) + { + Call_expression* call = this->vals_->front()->call_expression(); + size_t count = results->size(); + Expression_list* vals = new Expression_list; + for (size_t i = 0; i < count; ++i) + vals->push_back(Expression::make_call_result(call, i)); + delete this->vals_; + this->vals_ = vals; + } + + if (results->front().name().empty()) + return this; + + if (results_count != this->vals_->size()) + { + // Presumably an error which will be reported in check_types. + return this; + } + + // Assign to named return values and then return them. + + source_location loc = this->location(); + const Block* top = enclosing; + while (top->enclosing() != NULL) + top = top->enclosing(); + + const Bindings *bindings = top->bindings(); + Block* b = new Block(enclosing, loc); + + Expression_list* lhs = new Expression_list(); + Expression_list* rhs = new Expression_list(); + + Expression_list::const_iterator pe = this->vals_->begin(); + int i = 1; + for (Typed_identifier_list::const_iterator pr = results->begin(); + pr != results->end(); + ++pr, ++pe, ++i) + { + Named_object* rv = bindings->lookup_local(pr->name()); + if (rv == NULL || !rv->is_result_variable()) + { + // Presumably an error. + delete b; + delete lhs; + delete rhs; + return this; + } + + Expression* e = *pe; + + // Check types now so that we give a good error message. The + // result type is known. We determine the expression type + // early. + + Type *rvtype = rv->result_var_value()->type(); + Type_context type_context(rvtype, false); + e->determine_type(&type_context); + + std::string reason; + if (Type::are_assignable(rvtype, e->type(), &reason)) + { + Expression* ve = Expression::make_var_reference(rv, e->location()); + lhs->push_back(ve); + rhs->push_back(e); + } + else + { + if (reason.empty()) + error_at(e->location(), "incompatible type for return value %d", i); + else + error_at(e->location(), + "incompatible type for return value %d (%s)", + i, reason.c_str()); + } + } + gcc_assert(lhs->size() == rhs->size()); + + if (lhs->empty()) + ; + else if (lhs->size() == 1) + { + b->add_statement(Statement::make_assignment(lhs->front(), rhs->front(), + loc)); + delete lhs; + delete rhs; + } + else + b->add_statement(Statement::make_tuple_assignment(lhs, rhs, loc)); + + b->add_statement(Statement::make_return_statement(this->results_, NULL, + loc)); + + return Statement::make_block_statement(b, loc); +} + +// Determine types. + +void +Return_statement::do_determine_types() +{ + if (this->vals_ == NULL) + return; + const Typed_identifier_list* results = this->results_; + + Typed_identifier_list::const_iterator pt; + if (results != NULL) + pt = results->begin(); + for (Expression_list::iterator pe = this->vals_->begin(); + pe != this->vals_->end(); + ++pe) + { + if (results == NULL || pt == results->end()) + (*pe)->determine_type_no_context(); + else + { + Type_context context(pt->type(), false); + (*pe)->determine_type(&context); + ++pt; + } + } +} + +// Check types. + +void +Return_statement::do_check_types(Gogo*) +{ + if (this->vals_ == NULL) + return; + + const Typed_identifier_list* results = this->results_; + if (results == NULL) + { + this->report_error(_("return with value in function " + "with no return type")); + return; + } + + int i = 1; + Typed_identifier_list::const_iterator pt = results->begin(); + for (Expression_list::const_iterator pe = this->vals_->begin(); + pe != this->vals_->end(); + ++pe, ++pt, ++i) + { + if (pt == results->end()) + { + this->report_error(_("too many values in return statement")); + return; + } + std::string reason; + if (!Type::are_assignable(pt->type(), (*pe)->type(), &reason)) + { + if (reason.empty()) + error_at(this->location(), + "incompatible type for return value %d", + i); + else + error_at(this->location(), + "incompatible type for return value %d (%s)", + i, reason.c_str()); + this->set_is_error(); + } + else if (pt->type()->is_error_type() + || (*pe)->type()->is_error_type() + || pt->type()->is_undefined() + || (*pe)->type()->is_undefined()) + { + // Make sure we get the error for an undefined type. + pt->type()->base(); + (*pe)->type()->base(); + this->set_is_error(); + } + } + + if (pt != results->end()) + this->report_error(_("not enough values in return statement")); +} + +// Build a RETURN_EXPR tree. + +tree +Return_statement::do_get_tree(Translate_context* context) +{ + Function* function = context->function()->func_value(); + tree fndecl = function->get_decl(); + if (fndecl == error_mark_node || DECL_RESULT(fndecl) == error_mark_node) + return error_mark_node; + + const Typed_identifier_list* results = this->results_; + + if (this->vals_ == NULL) + { + tree stmt_list = NULL_TREE; + tree retval = function->return_value(context->gogo(), + context->function(), + this->location(), + &stmt_list); + tree set; + if (retval == NULL_TREE) + set = NULL_TREE; + else if (retval == error_mark_node) + return error_mark_node; + else + set = fold_build2_loc(this->location(), MODIFY_EXPR, void_type_node, + DECL_RESULT(fndecl), retval); + append_to_statement_list(this->build_stmt_1(RETURN_EXPR, set), + &stmt_list); + return stmt_list; + } + else if (this->vals_->size() == 1) + { + gcc_assert(!VOID_TYPE_P(TREE_TYPE(TREE_TYPE(fndecl)))); + tree val = (*this->vals_->begin())->get_tree(context); + gcc_assert(results != NULL && results->size() == 1); + val = Expression::convert_for_assignment(context, + results->begin()->type(), + (*this->vals_->begin())->type(), + val, this->location()); + if (val == error_mark_node) + return error_mark_node; + tree set = build2(MODIFY_EXPR, void_type_node, + DECL_RESULT(fndecl), val); + SET_EXPR_LOCATION(set, this->location()); + return this->build_stmt_1(RETURN_EXPR, set); + } + else + { + gcc_assert(!VOID_TYPE_P(TREE_TYPE(TREE_TYPE(fndecl)))); + tree stmt_list = NULL_TREE; + tree rettype = TREE_TYPE(DECL_RESULT(fndecl)); + tree retvar = create_tmp_var(rettype, "RESULT"); + gcc_assert(results != NULL && results->size() == this->vals_->size()); + Expression_list::const_iterator pv = this->vals_->begin(); + Typed_identifier_list::const_iterator pr = results->begin(); + for (tree field = TYPE_FIELDS(rettype); + field != NULL_TREE; + ++pv, ++pr, field = DECL_CHAIN(field)) + { + gcc_assert(pv != this->vals_->end()); + tree val = (*pv)->get_tree(context); + val = Expression::convert_for_assignment(context, pr->type(), + (*pv)->type(), val, + this->location()); + if (val == error_mark_node) + return error_mark_node; + tree set = build2(MODIFY_EXPR, void_type_node, + build3(COMPONENT_REF, TREE_TYPE(field), + retvar, field, NULL_TREE), + val); + SET_EXPR_LOCATION(set, this->location()); + append_to_statement_list(set, &stmt_list); + } + tree set = build2(MODIFY_EXPR, void_type_node, DECL_RESULT(fndecl), + retvar); + append_to_statement_list(this->build_stmt_1(RETURN_EXPR, set), + &stmt_list); + return stmt_list; + } +} + +// Make a return statement. + +Statement* +Statement::make_return_statement(const Typed_identifier_list* results, + Expression_list* vals, + source_location location) +{ + return new Return_statement(results, vals, location); +} + +// A break or continue statement. + +class Bc_statement : public Statement +{ + public: + Bc_statement(bool is_break, Unnamed_label* label, source_location location) + : Statement(STATEMENT_BREAK_OR_CONTINUE, location), + label_(label), is_break_(is_break) + { } + + bool + is_break() const + { return this->is_break_; } + + protected: + int + do_traverse(Traverse*) + { return TRAVERSE_CONTINUE; } + + bool + do_may_fall_through() const + { return false; } + + tree + do_get_tree(Translate_context*) + { return this->label_->get_goto(this->location()); } + + private: + // The label that this branches to. + Unnamed_label* label_; + // True if this is "break", false if it is "continue". + bool is_break_; +}; + +// Make a break statement. + +Statement* +Statement::make_break_statement(Unnamed_label* label, source_location location) +{ + return new Bc_statement(true, label, location); +} + +// Make a continue statement. + +Statement* +Statement::make_continue_statement(Unnamed_label* label, + source_location location) +{ + return new Bc_statement(false, label, location); +} + +// A goto statement. + +class Goto_statement : public Statement +{ + public: + Goto_statement(Label* label, source_location location) + : Statement(STATEMENT_GOTO, location), + label_(label) + { } + + protected: + int + do_traverse(Traverse*) + { return TRAVERSE_CONTINUE; } + + void + do_check_types(Gogo*); + + bool + do_may_fall_through() const + { return false; } + + tree + do_get_tree(Translate_context*); + + private: + Label* label_; +}; + +// Check types for a label. There aren't any types per se, but we use +// this to give an error if the label was never defined. + +void +Goto_statement::do_check_types(Gogo*) +{ + if (!this->label_->is_defined()) + { + error_at(this->location(), "reference to undefined label %qs", + Gogo::message_name(this->label_->name()).c_str()); + this->set_is_error(); + } +} + +// Return the tree for the goto statement. + +tree +Goto_statement::do_get_tree(Translate_context*) +{ + return this->build_stmt_1(GOTO_EXPR, this->label_->get_decl()); +} + +// Make a goto statement. + +Statement* +Statement::make_goto_statement(Label* label, source_location location) +{ + return new Goto_statement(label, location); +} + +// A goto statement to an unnamed label. + +class Goto_unnamed_statement : public Statement +{ + public: + Goto_unnamed_statement(Unnamed_label* label, source_location location) + : Statement(STATEMENT_GOTO_UNNAMED, location), + label_(label) + { } + + protected: + int + do_traverse(Traverse*) + { return TRAVERSE_CONTINUE; } + + bool + do_may_fall_through() const + { return false; } + + tree + do_get_tree(Translate_context*) + { return this->label_->get_goto(this->location()); } + + private: + Unnamed_label* label_; +}; + +// Make a goto statement to an unnamed label. + +Statement* +Statement::make_goto_unnamed_statement(Unnamed_label* label, + source_location location) +{ + return new Goto_unnamed_statement(label, location); +} + +// Class Label_statement. + +// Traversal. + +int +Label_statement::do_traverse(Traverse*) +{ + return TRAVERSE_CONTINUE; +} + +// Return a tree defining this label. + +tree +Label_statement::do_get_tree(Translate_context*) +{ + return this->build_stmt_1(LABEL_EXPR, this->label_->get_decl()); +} + +// Make a label statement. + +Statement* +Statement::make_label_statement(Label* label, source_location location) +{ + return new Label_statement(label, location); +} + +// An unnamed label statement. + +class Unnamed_label_statement : public Statement +{ + public: + Unnamed_label_statement(Unnamed_label* label) + : Statement(STATEMENT_UNNAMED_LABEL, label->location()), + label_(label) + { } + + protected: + int + do_traverse(Traverse*) + { return TRAVERSE_CONTINUE; } + + tree + do_get_tree(Translate_context*) + { return this->label_->get_definition(); } + + private: + // The label. + Unnamed_label* label_; +}; + +// Make an unnamed label statement. + +Statement* +Statement::make_unnamed_label_statement(Unnamed_label* label) +{ + return new Unnamed_label_statement(label); +} + +// An if statement. + +class If_statement : public Statement +{ + public: + If_statement(Expression* cond, Block* then_block, Block* else_block, + source_location location) + : Statement(STATEMENT_IF, location), + cond_(cond), then_block_(then_block), else_block_(else_block) + { } + + protected: + int + do_traverse(Traverse*); + + void + do_determine_types(); + + void + do_check_types(Gogo*); + + bool + do_may_fall_through() const; + + tree + do_get_tree(Translate_context*); + + private: + Expression* cond_; + Block* then_block_; + Block* else_block_; +}; + +// Traversal. + +int +If_statement::do_traverse(Traverse* traverse) +{ + if (this->cond_ != NULL) + { + if (this->traverse_expression(traverse, &this->cond_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if (this->then_block_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (this->else_block_ != NULL) + { + if (this->else_block_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +void +If_statement::do_determine_types() +{ + if (this->cond_ != NULL) + { + Type_context context(Type::lookup_bool_type(), false); + this->cond_->determine_type(&context); + } + this->then_block_->determine_types(); + if (this->else_block_ != NULL) + this->else_block_->determine_types(); +} + +// Check types. + +void +If_statement::do_check_types(Gogo*) +{ + if (this->cond_ != NULL) + { + Type* type = this->cond_->type(); + if (type->is_error_type()) + this->set_is_error(); + else if (!type->is_boolean_type()) + this->report_error(_("expected boolean expression")); + } +} + +// Whether the overall statement may fall through. + +bool +If_statement::do_may_fall_through() const +{ + return (this->else_block_ == NULL + || this->then_block_->may_fall_through() + || this->else_block_->may_fall_through()); +} + +// Get tree. + +tree +If_statement::do_get_tree(Translate_context* context) +{ + gcc_assert(this->cond_ == NULL + || this->cond_->type()->is_boolean_type() + || this->cond_->type()->is_error_type()); + tree cond_tree = (this->cond_ == NULL + ? boolean_true_node + : this->cond_->get_tree(context)); + tree then_tree = this->then_block_->get_tree(context); + tree else_tree = (this->else_block_ == NULL + ? NULL_TREE + : this->else_block_->get_tree(context)); + if (cond_tree == error_mark_node + || then_tree == error_mark_node + || else_tree == error_mark_node) + return error_mark_node; + tree ret = build3(COND_EXPR, void_type_node, cond_tree, then_tree, + else_tree); + SET_EXPR_LOCATION(ret, this->location()); + return ret; +} + +// Make an if statement. + +Statement* +Statement::make_if_statement(Expression* cond, Block* then_block, + Block* else_block, source_location location) +{ + return new If_statement(cond, then_block, else_block, location); +} + +// Class Case_clauses::Case_clause. + +// Traversal. + +int +Case_clauses::Case_clause::traverse(Traverse* traverse) +{ + if (this->cases_ != NULL + && (traverse->traverse_mask() + & (Traverse::traverse_types | Traverse::traverse_expressions)) != 0) + { + if (this->cases_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if (this->statements_ != NULL) + { + if (this->statements_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +// Check whether all the case expressions are integer constants. + +bool +Case_clauses::Case_clause::is_constant() const +{ + if (this->cases_ != NULL) + { + for (Expression_list::const_iterator p = this->cases_->begin(); + p != this->cases_->end(); + ++p) + if (!(*p)->is_constant() || (*p)->type()->integer_type() == NULL) + return false; + } + return true; +} + +// Lower a case clause for a nonconstant switch. VAL_TEMP is the +// value we are switching on; it may be NULL. If START_LABEL is not +// NULL, it goes at the start of the statements, after the condition +// test. We branch to FINISH_LABEL at the end of the statements. + +void +Case_clauses::Case_clause::lower(Block* b, Temporary_statement* val_temp, + Unnamed_label* start_label, + Unnamed_label* finish_label) const +{ + source_location loc = this->location_; + Unnamed_label* next_case_label; + if (this->cases_ == NULL || this->cases_->empty()) + { + gcc_assert(this->is_default_); + next_case_label = NULL; + } + else + { + Expression* cond = NULL; + + for (Expression_list::const_iterator p = this->cases_->begin(); + p != this->cases_->end(); + ++p) + { + Expression* this_cond; + if (val_temp == NULL) + this_cond = *p; + else + { + Expression* ref = Expression::make_temporary_reference(val_temp, + loc); + this_cond = Expression::make_binary(OPERATOR_EQEQ, ref, *p, loc); + } + + if (cond == NULL) + cond = this_cond; + else + cond = Expression::make_binary(OPERATOR_OROR, cond, this_cond, loc); + } + + Block* then_block = new Block(b, loc); + next_case_label = new Unnamed_label(UNKNOWN_LOCATION); + Statement* s = Statement::make_goto_unnamed_statement(next_case_label, + loc); + then_block->add_statement(s); + + // if !COND { goto NEXT_CASE_LABEL } + cond = Expression::make_unary(OPERATOR_NOT, cond, loc); + s = Statement::make_if_statement(cond, then_block, NULL, loc); + b->add_statement(s); + } + + if (start_label != NULL) + b->add_statement(Statement::make_unnamed_label_statement(start_label)); + + if (this->statements_ != NULL) + b->add_statement(Statement::make_block_statement(this->statements_, loc)); + + Statement* s = Statement::make_goto_unnamed_statement(finish_label, loc); + b->add_statement(s); + + if (next_case_label != NULL) + b->add_statement(Statement::make_unnamed_label_statement(next_case_label)); +} + +// Determine types. + +void +Case_clauses::Case_clause::determine_types(Type* type) +{ + if (this->cases_ != NULL) + { + Type_context case_context(type, false); + for (Expression_list::iterator p = this->cases_->begin(); + p != this->cases_->end(); + ++p) + (*p)->determine_type(&case_context); + } + if (this->statements_ != NULL) + this->statements_->determine_types(); +} + +// Check types. Returns false if there was an error. + +bool +Case_clauses::Case_clause::check_types(Type* type) +{ + if (this->cases_ != NULL) + { + for (Expression_list::iterator p = this->cases_->begin(); + p != this->cases_->end(); + ++p) + { + if (!Type::are_assignable(type, (*p)->type(), NULL) + && !Type::are_assignable((*p)->type(), type, NULL)) + { + error_at((*p)->location(), + "type mismatch between switch value and case clause"); + return false; + } + } + } + return true; +} + +// Return true if this clause may fall through to the following +// statements. Note that this is not the same as whether the case +// uses the "fallthrough" keyword. + +bool +Case_clauses::Case_clause::may_fall_through() const +{ + if (this->statements_ == NULL) + return true; + return this->statements_->may_fall_through(); +} + +// Build up the body of a SWITCH_EXPR. + +void +Case_clauses::Case_clause::get_constant_tree(Translate_context* context, + Unnamed_label* break_label, + Case_constants* case_constants, + tree* stmt_list) const +{ + if (this->cases_ != NULL) + { + for (Expression_list::const_iterator p = this->cases_->begin(); + p != this->cases_->end(); + ++p) + { + Type* itype; + mpz_t ival; + mpz_init(ival); + if (!(*p)->integer_constant_value(true, ival, &itype)) + { + // Something went wrong. This can happen with a + // negative constant and an unsigned switch value. + gcc_assert(saw_errors()); + continue; + } + gcc_assert(itype != NULL); + tree type_tree = itype->get_tree(context->gogo()); + tree val = Expression::integer_constant_tree(ival, type_tree); + mpz_clear(ival); + + if (val != error_mark_node) + { + gcc_assert(TREE_CODE(val) == INTEGER_CST); + + std::pair<Case_constants::iterator, bool> ins = + case_constants->insert(val); + if (!ins.second) + { + // Value was already present. + warning_at(this->location_, 0, + "duplicate case value will never match"); + continue; + } + + tree label = create_artificial_label(this->location_); + append_to_statement_list(build3(CASE_LABEL_EXPR, void_type_node, + val, NULL_TREE, label), + stmt_list); + } + } + } + + if (this->is_default_) + { + tree label = create_artificial_label(this->location_); + append_to_statement_list(build3(CASE_LABEL_EXPR, void_type_node, + NULL_TREE, NULL_TREE, label), + stmt_list); + } + + if (this->statements_ != NULL) + { + tree block_tree = this->statements_->get_tree(context); + if (block_tree != error_mark_node) + append_to_statement_list(block_tree, stmt_list); + } + + if (!this->is_fallthrough_) + append_to_statement_list(break_label->get_goto(this->location_), stmt_list); +} + +// Class Case_clauses. + +// Traversal. + +int +Case_clauses::traverse(Traverse* traverse) +{ + for (Clauses::iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + { + if (p->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +// Check whether all the case expressions are constant. + +bool +Case_clauses::is_constant() const +{ + for (Clauses::const_iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + if (!p->is_constant()) + return false; + return true; +} + +// Lower case clauses for a nonconstant switch. + +void +Case_clauses::lower(Block* b, Temporary_statement* val_temp, + Unnamed_label* break_label) const +{ + // The default case. + const Case_clause* default_case = NULL; + + // The label for the fallthrough of the previous case. + Unnamed_label* last_fallthrough_label = NULL; + + // The label for the start of the default case. This is used if the + // case before the default case falls through. + Unnamed_label* default_start_label = NULL; + + // The label for the end of the default case. This normally winds + // up as BREAK_LABEL, but it will be different if the default case + // falls through. + Unnamed_label* default_finish_label = NULL; + + for (Clauses::const_iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + { + // The label to use for the start of the statements for this + // case. This is NULL unless the previous case falls through. + Unnamed_label* start_label = last_fallthrough_label; + + // The label to jump to after the end of the statements for this + // case. + Unnamed_label* finish_label = break_label; + + last_fallthrough_label = NULL; + if (p->is_fallthrough() && p + 1 != this->clauses_.end()) + { + finish_label = new Unnamed_label(p->location()); + last_fallthrough_label = finish_label; + } + + if (!p->is_default()) + p->lower(b, val_temp, start_label, finish_label); + else + { + // We have to move the default case to the end, so that we + // only use it if all the other tests fail. + default_case = &*p; + default_start_label = start_label; + default_finish_label = finish_label; + } + } + + if (default_case != NULL) + default_case->lower(b, val_temp, default_start_label, + default_finish_label); + +} + +// Determine types. + +void +Case_clauses::determine_types(Type* type) +{ + for (Clauses::iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + p->determine_types(type); +} + +// Check types. Returns false if there was an error. + +bool +Case_clauses::check_types(Type* type) +{ + bool ret = true; + for (Clauses::iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + { + if (!p->check_types(type)) + ret = false; + } + return ret; +} + +// Return true if these clauses may fall through to the statements +// following the switch statement. + +bool +Case_clauses::may_fall_through() const +{ + bool found_default = false; + for (Clauses::const_iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + { + if (p->may_fall_through() && !p->is_fallthrough()) + return true; + if (p->is_default()) + found_default = true; + } + return !found_default; +} + +// Return a tree when all case expressions are constants. + +tree +Case_clauses::get_constant_tree(Translate_context* context, + Unnamed_label* break_label) const +{ + Case_constants case_constants; + tree stmt_list = NULL_TREE; + for (Clauses::const_iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + p->get_constant_tree(context, break_label, &case_constants, + &stmt_list); + return stmt_list; +} + +// A constant switch statement. A Switch_statement is lowered to this +// when all the cases are constants. + +class Constant_switch_statement : public Statement +{ + public: + Constant_switch_statement(Expression* val, Case_clauses* clauses, + Unnamed_label* break_label, + source_location location) + : Statement(STATEMENT_CONSTANT_SWITCH, location), + val_(val), clauses_(clauses), break_label_(break_label) + { } + + protected: + int + do_traverse(Traverse*); + + void + do_determine_types(); + + void + do_check_types(Gogo*); + + bool + do_may_fall_through() const; + + tree + do_get_tree(Translate_context*); + + private: + // The value to switch on. + Expression* val_; + // The case clauses. + Case_clauses* clauses_; + // The break label, if needed. + Unnamed_label* break_label_; +}; + +// Traversal. + +int +Constant_switch_statement::do_traverse(Traverse* traverse) +{ + if (this->traverse_expression(traverse, &this->val_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return this->clauses_->traverse(traverse); +} + +// Determine types. + +void +Constant_switch_statement::do_determine_types() +{ + this->val_->determine_type_no_context(); + this->clauses_->determine_types(this->val_->type()); +} + +// Check types. + +void +Constant_switch_statement::do_check_types(Gogo*) +{ + if (!this->clauses_->check_types(this->val_->type())) + this->set_is_error(); +} + +// Return whether this switch may fall through. + +bool +Constant_switch_statement::do_may_fall_through() const +{ + if (this->clauses_ == NULL) + return true; + + // If we have a break label, then some case needed it. That implies + // that the switch statement as a whole can fall through. + if (this->break_label_ != NULL) + return true; + + return this->clauses_->may_fall_through(); +} + +// Convert to GENERIC. + +tree +Constant_switch_statement::do_get_tree(Translate_context* context) +{ + tree switch_val_tree = this->val_->get_tree(context); + + Unnamed_label* break_label = this->break_label_; + if (break_label == NULL) + break_label = new Unnamed_label(this->location()); + + tree stmt_list = NULL_TREE; + tree s = build3(SWITCH_EXPR, void_type_node, switch_val_tree, + this->clauses_->get_constant_tree(context, break_label), + NULL_TREE); + SET_EXPR_LOCATION(s, this->location()); + append_to_statement_list(s, &stmt_list); + + append_to_statement_list(break_label->get_definition(), &stmt_list); + + return stmt_list; +} + +// Class Switch_statement. + +// Traversal. + +int +Switch_statement::do_traverse(Traverse* traverse) +{ + if (this->val_ != NULL) + { + if (this->traverse_expression(traverse, &this->val_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return this->clauses_->traverse(traverse); +} + +// Lower a Switch_statement to a Constant_switch_statement or a series +// of if statements. + +Statement* +Switch_statement::do_lower(Gogo*, Block* enclosing) +{ + source_location loc = this->location(); + + if (this->val_ != NULL + && (this->val_->is_error_expression() + || this->val_->type()->is_error_type())) + return Statement::make_error_statement(loc); + + if (this->val_ != NULL + && this->val_->type()->integer_type() != NULL + && !this->clauses_->empty() + && this->clauses_->is_constant()) + return new Constant_switch_statement(this->val_, this->clauses_, + this->break_label_, loc); + + Block* b = new Block(enclosing, loc); + + if (this->clauses_->empty()) + { + Expression* val = this->val_; + if (val == NULL) + val = Expression::make_boolean(true, loc); + return Statement::make_statement(val); + } + + Temporary_statement* val_temp; + if (this->val_ == NULL) + val_temp = NULL; + else + { + // var val_temp VAL_TYPE = VAL + val_temp = Statement::make_temporary(NULL, this->val_, loc); + b->add_statement(val_temp); + } + + this->clauses_->lower(b, val_temp, this->break_label()); + + Statement* s = Statement::make_unnamed_label_statement(this->break_label_); + b->add_statement(s); + + return Statement::make_block_statement(b, loc); +} + +// Return the break label for this switch statement, creating it if +// necessary. + +Unnamed_label* +Switch_statement::break_label() +{ + if (this->break_label_ == NULL) + this->break_label_ = new Unnamed_label(this->location()); + return this->break_label_; +} + +// Make a switch statement. + +Switch_statement* +Statement::make_switch_statement(Expression* val, source_location location) +{ + return new Switch_statement(val, location); +} + +// Class Type_case_clauses::Type_case_clause. + +// Traversal. + +int +Type_case_clauses::Type_case_clause::traverse(Traverse* traverse) +{ + if (!this->is_default_ + && ((traverse->traverse_mask() + & (Traverse::traverse_types | Traverse::traverse_expressions)) != 0) + && Type::traverse(this->type_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (this->statements_ != NULL) + return this->statements_->traverse(traverse); + return TRAVERSE_CONTINUE; +} + +// Lower one clause in a type switch. Add statements to the block B. +// The type descriptor we are switching on is in DESCRIPTOR_TEMP. +// BREAK_LABEL is the label at the end of the type switch. +// *STMTS_LABEL, if not NULL, is a label to put at the start of the +// statements. + +void +Type_case_clauses::Type_case_clause::lower(Block* b, + Temporary_statement* descriptor_temp, + Unnamed_label* break_label, + Unnamed_label** stmts_label) const +{ + source_location loc = this->location_; + + Unnamed_label* next_case_label = NULL; + if (!this->is_default_) + { + Type* type = this->type_; + + Expression* cond; + // The language permits case nil, which is of course a constant + // rather than a type. It will appear here as an invalid + // forwarding type. + if (type->is_nil_constant_as_type()) + { + Expression* ref = + Expression::make_temporary_reference(descriptor_temp, loc); + cond = Expression::make_binary(OPERATOR_EQEQ, ref, + Expression::make_nil(loc), + loc); + } + else + { + Expression* func; + if (type->interface_type() == NULL) + { + // func ifacetypeeq(*descriptor, *descriptor) bool + static Named_object* ifacetypeeq; + if (ifacetypeeq == NULL) + { + const source_location bloc = BUILTINS_LOCATION; + Typed_identifier_list* param_types = + new Typed_identifier_list(); + Type* descriptor_type = Type::make_type_descriptor_ptr_type(); + param_types->push_back(Typed_identifier("a", descriptor_type, + bloc)); + param_types->push_back(Typed_identifier("b", descriptor_type, + bloc)); + Typed_identifier_list* ret_types = + new Typed_identifier_list(); + Type* bool_type = Type::lookup_bool_type(); + ret_types->push_back(Typed_identifier("", bool_type, bloc)); + Function_type* fntype = Type::make_function_type(NULL, + param_types, + ret_types, + bloc); + ifacetypeeq = + Named_object::make_function_declaration("ifacetypeeq", NULL, + fntype, bloc); + const char* n = "runtime.ifacetypeeq"; + ifacetypeeq->func_declaration_value()->set_asm_name(n); + } + + // ifacetypeeq(descriptor_temp, DESCRIPTOR) + func = Expression::make_func_reference(ifacetypeeq, NULL, loc); + } + else + { + // func ifaceI2Tp(*descriptor, *descriptor) bool + static Named_object* ifaceI2Tp; + if (ifaceI2Tp == NULL) + { + const source_location bloc = BUILTINS_LOCATION; + Typed_identifier_list* param_types = + new Typed_identifier_list(); + Type* descriptor_type = Type::make_type_descriptor_ptr_type(); + param_types->push_back(Typed_identifier("a", descriptor_type, + bloc)); + param_types->push_back(Typed_identifier("b", descriptor_type, + bloc)); + Typed_identifier_list* ret_types = + new Typed_identifier_list(); + Type* bool_type = Type::lookup_bool_type(); + ret_types->push_back(Typed_identifier("", bool_type, bloc)); + Function_type* fntype = Type::make_function_type(NULL, + param_types, + ret_types, + bloc); + ifaceI2Tp = + Named_object::make_function_declaration("ifaceI2Tp", NULL, + fntype, bloc); + const char* n = "runtime.ifaceI2Tp"; + ifaceI2Tp->func_declaration_value()->set_asm_name(n); + } + + // ifaceI2Tp(descriptor_temp, DESCRIPTOR) + func = Expression::make_func_reference(ifaceI2Tp, NULL, loc); + } + Expression_list* params = new Expression_list(); + params->push_back(Expression::make_type_descriptor(type, loc)); + Expression* ref = + Expression::make_temporary_reference(descriptor_temp, loc); + params->push_back(ref); + cond = Expression::make_call(func, params, false, loc); + } + + Unnamed_label* dest; + if (!this->is_fallthrough_) + { + // if !COND { goto NEXT_CASE_LABEL } + next_case_label = new Unnamed_label(UNKNOWN_LOCATION); + dest = next_case_label; + cond = Expression::make_unary(OPERATOR_NOT, cond, loc); + } + else + { + // if COND { goto STMTS_LABEL } + gcc_assert(stmts_label != NULL); + if (*stmts_label == NULL) + *stmts_label = new Unnamed_label(UNKNOWN_LOCATION); + dest = *stmts_label; + } + Block* then_block = new Block(b, loc); + Statement* s = Statement::make_goto_unnamed_statement(dest, loc); + then_block->add_statement(s); + s = Statement::make_if_statement(cond, then_block, NULL, loc); + b->add_statement(s); + } + + if (this->statements_ != NULL + || (!this->is_fallthrough_ + && stmts_label != NULL + && *stmts_label != NULL)) + { + gcc_assert(!this->is_fallthrough_); + if (stmts_label != NULL && *stmts_label != NULL) + { + gcc_assert(!this->is_default_); + if (this->statements_ != NULL) + (*stmts_label)->set_location(this->statements_->start_location()); + Statement* s = Statement::make_unnamed_label_statement(*stmts_label); + b->add_statement(s); + *stmts_label = NULL; + } + if (this->statements_ != NULL) + b->add_statement(Statement::make_block_statement(this->statements_, + loc)); + } + + if (this->is_fallthrough_) + gcc_assert(next_case_label == NULL); + else + { + source_location gloc = (this->statements_ == NULL + ? loc + : this->statements_->end_location()); + b->add_statement(Statement::make_goto_unnamed_statement(break_label, + gloc)); + if (next_case_label != NULL) + { + Statement* s = + Statement::make_unnamed_label_statement(next_case_label); + b->add_statement(s); + } + } +} + +// Class Type_case_clauses. + +// Traversal. + +int +Type_case_clauses::traverse(Traverse* traverse) +{ + for (Type_clauses::iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + { + if (p->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +// Check for duplicate types. + +void +Type_case_clauses::check_duplicates() const +{ + typedef Unordered_set_hash(const Type*, Type_hash_identical, + Type_identical) Types_seen; + Types_seen types_seen; + for (Type_clauses::const_iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + { + Type* t = p->type(); + if (t == NULL) + continue; + if (t->is_nil_constant_as_type()) + t = Type::make_nil_type(); + std::pair<Types_seen::iterator, bool> ins = types_seen.insert(t); + if (!ins.second) + error_at(p->location(), "duplicate type in switch"); + } +} + +// Lower the clauses in a type switch. Add statements to the block B. +// The type descriptor we are switching on is in DESCRIPTOR_TEMP. +// BREAK_LABEL is the label at the end of the type switch. + +void +Type_case_clauses::lower(Block* b, Temporary_statement* descriptor_temp, + Unnamed_label* break_label) const +{ + const Type_case_clause* default_case = NULL; + + Unnamed_label* stmts_label = NULL; + for (Type_clauses::const_iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + { + if (!p->is_default()) + p->lower(b, descriptor_temp, break_label, &stmts_label); + else + { + // We are generating a series of tests, which means that we + // need to move the default case to the end. + default_case = &*p; + } + } + gcc_assert(stmts_label == NULL); + + if (default_case != NULL) + default_case->lower(b, descriptor_temp, break_label, NULL); +} + +// Class Type_switch_statement. + +// Traversal. + +int +Type_switch_statement::do_traverse(Traverse* traverse) +{ + if (this->var_ == NULL) + { + if (this->traverse_expression(traverse, &this->expr_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if (this->clauses_ != NULL) + return this->clauses_->traverse(traverse); + return TRAVERSE_CONTINUE; +} + +// Lower a type switch statement to a series of if statements. The gc +// compiler is able to generate a table in some cases. However, that +// does not work for us because we may have type descriptors in +// different shared libraries, so we can't compare them with simple +// equality testing. + +Statement* +Type_switch_statement::do_lower(Gogo*, Block* enclosing) +{ + const source_location loc = this->location(); + + if (this->clauses_ != NULL) + this->clauses_->check_duplicates(); + + Block* b = new Block(enclosing, loc); + + Type* val_type = (this->var_ != NULL + ? this->var_->var_value()->type() + : this->expr_->type()); + + // var descriptor_temp DESCRIPTOR_TYPE + Type* descriptor_type = Type::make_type_descriptor_ptr_type(); + Temporary_statement* descriptor_temp = + Statement::make_temporary(descriptor_type, NULL, loc); + b->add_statement(descriptor_temp); + + if (val_type->interface_type() == NULL) + { + // Doing a type switch on a non-interface type. Should we issue + // a warning for this case? + Expression* lhs = Expression::make_temporary_reference(descriptor_temp, + loc); + Expression* rhs; + if (val_type->is_nil_type()) + rhs = Expression::make_nil(loc); + else + { + if (val_type->is_abstract()) + val_type = val_type->make_non_abstract_type(); + rhs = Expression::make_type_descriptor(val_type, loc); + } + Statement* s = Statement::make_assignment(lhs, rhs, loc); + b->add_statement(s); + } + else + { + const source_location bloc = BUILTINS_LOCATION; + + // func {efacetype,ifacetype}(*interface) *descriptor + // FIXME: This should be inlined. + Typed_identifier_list* param_types = new Typed_identifier_list(); + param_types->push_back(Typed_identifier("i", val_type, bloc)); + Typed_identifier_list* ret_types = new Typed_identifier_list(); + ret_types->push_back(Typed_identifier("", descriptor_type, bloc)); + Function_type* fntype = Type::make_function_type(NULL, param_types, + ret_types, bloc); + bool is_empty = val_type->interface_type()->is_empty(); + const char* fnname = is_empty ? "efacetype" : "ifacetype"; + Named_object* fn = + Named_object::make_function_declaration(fnname, NULL, fntype, bloc); + const char* asm_name = (is_empty + ? "runtime.efacetype" + : "runtime.ifacetype"); + fn->func_declaration_value()->set_asm_name(asm_name); + + // descriptor_temp = ifacetype(val_temp) + Expression* func = Expression::make_func_reference(fn, NULL, loc); + Expression_list* params = new Expression_list(); + Expression* ref; + if (this->var_ == NULL) + ref = this->expr_; + else + ref = Expression::make_var_reference(this->var_, loc); + params->push_back(ref); + Expression* call = Expression::make_call(func, params, false, loc); + Expression* lhs = Expression::make_temporary_reference(descriptor_temp, + loc); + Statement* s = Statement::make_assignment(lhs, call, loc); + b->add_statement(s); + } + + if (this->clauses_ != NULL) + this->clauses_->lower(b, descriptor_temp, this->break_label()); + + Statement* s = Statement::make_unnamed_label_statement(this->break_label_); + b->add_statement(s); + + return Statement::make_block_statement(b, loc); +} + +// Return the break label for this type switch statement, creating it +// if necessary. + +Unnamed_label* +Type_switch_statement::break_label() +{ + if (this->break_label_ == NULL) + this->break_label_ = new Unnamed_label(this->location()); + return this->break_label_; +} + +// Make a type switch statement. + +Type_switch_statement* +Statement::make_type_switch_statement(Named_object* var, Expression* expr, + source_location location) +{ + return new Type_switch_statement(var, expr, location); +} + +// Class Select_clauses::Select_clause. + +// Traversal. + +int +Select_clauses::Select_clause::traverse(Traverse* traverse) +{ + if (!this->is_lowered_ + && (traverse->traverse_mask() + & (Traverse::traverse_types | Traverse::traverse_expressions)) != 0) + { + if (this->channel_ != NULL) + { + if (Expression::traverse(&this->channel_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if (this->val_ != NULL) + { + if (Expression::traverse(&this->val_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + } + if (this->statements_ != NULL) + { + if (this->statements_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +// Lowering. Here we pull out the channel and the send values, to +// enforce the order of evaluation. We also add explicit send and +// receive statements to the clauses. + +void +Select_clauses::Select_clause::lower(Block* b) +{ + if (this->is_default_) + { + gcc_assert(this->channel_ == NULL && this->val_ == NULL); + this->is_lowered_ = true; + return; + } + + source_location loc = this->location_; + + // Evaluate the channel before the select statement. + Temporary_statement* channel_temp = Statement::make_temporary(NULL, + this->channel_, + loc); + b->add_statement(channel_temp); + this->channel_ = Expression::make_temporary_reference(channel_temp, loc); + + // If this is a send clause, evaluate the value to send before the + // select statement. + Temporary_statement* val_temp = NULL; + if (this->is_send_) + { + val_temp = Statement::make_temporary(NULL, this->val_, loc); + b->add_statement(val_temp); + } + + // Add the send or receive before the rest of the statements if any. + Block *init = new Block(b, loc); + Expression* ref = Expression::make_temporary_reference(channel_temp, loc); + if (this->is_send_) + { + Expression* ref2 = Expression::make_temporary_reference(val_temp, loc); + Send_expression* send = Expression::make_send(ref, ref2, loc); + send->discarding_value(); + send->set_for_select(); + init->add_statement(Statement::make_statement(send)); + } + else + { + Receive_expression* recv = Expression::make_receive(ref, loc); + recv->set_for_select(); + if (this->val_ != NULL) + { + gcc_assert(this->var_ == NULL); + init->add_statement(Statement::make_assignment(this->val_, recv, + loc)); + } + else if (this->var_ != NULL) + { + this->var_->var_value()->set_init(recv); + this->var_->var_value()->clear_type_from_chan_element(); + } + else + { + recv->discarding_value(); + init->add_statement(Statement::make_statement(recv)); + } + } + + if (this->statements_ != NULL) + init->add_statement(Statement::make_block_statement(this->statements_, + loc)); + + this->statements_ = init; + + // Now all references should be handled through the statements, not + // through here. + this->is_lowered_ = true; + this->val_ = NULL; + this->var_ = NULL; +} + +// Determine types. + +void +Select_clauses::Select_clause::determine_types() +{ + gcc_assert(this->is_lowered_); + if (this->statements_ != NULL) + this->statements_->determine_types(); +} + +// Whether this clause may fall through to the statement which follows +// the overall select statement. + +bool +Select_clauses::Select_clause::may_fall_through() const +{ + if (this->statements_ == NULL) + return true; + return this->statements_->may_fall_through(); +} + +// Return a tree for the statements to execute. + +tree +Select_clauses::Select_clause::get_statements_tree(Translate_context* context) +{ + if (this->statements_ == NULL) + return NULL_TREE; + return this->statements_->get_tree(context); +} + +// Class Select_clauses. + +// Traversal. + +int +Select_clauses::traverse(Traverse* traverse) +{ + for (Clauses::iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + { + if (p->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +// Lowering. Here we pull out the channel and the send values, to +// enforce the order of evaluation. We also add explicit send and +// receive statements to the clauses. + +void +Select_clauses::lower(Block* b) +{ + for (Clauses::iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + p->lower(b); +} + +// Determine types. + +void +Select_clauses::determine_types() +{ + for (Clauses::iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + p->determine_types(); +} + +// Return whether these select clauses fall through to the statement +// following the overall select statement. + +bool +Select_clauses::may_fall_through() const +{ + for (Clauses::const_iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + if (p->may_fall_through()) + return true; + return false; +} + +// Return a tree. We build a call to +// size_t __go_select(size_t count, _Bool has_default, +// channel* channels, _Bool* is_send) +// +// There are COUNT entries in the CHANNELS and IS_SEND arrays. The +// value in the IS_SEND array is true for send, false for receive. +// __go_select returns an integer from 0 to COUNT, inclusive. A +// return of 0 means that the default case should be run; this only +// happens if HAS_DEFAULT is non-zero. Otherwise the number indicates +// the case to run. + +// FIXME: This doesn't handle channels which send interface types +// where the receiver has a static type which matches that interface. + +tree +Select_clauses::get_tree(Translate_context* context, + Unnamed_label *break_label, + source_location location) +{ + size_t count = this->clauses_.size(); + VEC(constructor_elt, gc)* chan_init = VEC_alloc(constructor_elt, gc, count); + VEC(constructor_elt, gc)* is_send_init = VEC_alloc(constructor_elt, gc, + count); + Select_clause* default_clause = NULL; + tree final_stmt_list = NULL_TREE; + tree channel_type_tree = NULL_TREE; + + size_t i = 0; + for (Clauses::iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + { + if (p->is_default()) + { + default_clause = &*p; + --count; + continue; + } + + if (p->channel()->type()->channel_type() == NULL) + { + // We should have given an error in the send or receive + // statement we created via lowering. + gcc_assert(saw_errors()); + return error_mark_node; + } + + tree channel_tree = p->channel()->get_tree(context); + if (channel_tree == error_mark_node) + return error_mark_node; + channel_type_tree = TREE_TYPE(channel_tree); + + constructor_elt* elt = VEC_quick_push(constructor_elt, chan_init, NULL); + elt->index = build_int_cstu(sizetype, i); + elt->value = channel_tree; + + elt = VEC_quick_push(constructor_elt, is_send_init, NULL); + elt->index = build_int_cstu(sizetype, i); + elt->value = p->is_send() ? boolean_true_node : boolean_false_node; + + ++i; + } + gcc_assert(i == count); + + if (i == 0 && default_clause != NULL) + { + // There is only a default clause. + gcc_assert(final_stmt_list == NULL_TREE); + tree stmt_list = NULL_TREE; + append_to_statement_list(default_clause->get_statements_tree(context), + &stmt_list); + append_to_statement_list(break_label->get_definition(), &stmt_list); + return stmt_list; + } + + tree pointer_chan_type_tree = (channel_type_tree == NULL_TREE + ? ptr_type_node + : build_pointer_type(channel_type_tree)); + tree chans_arg; + tree pointer_boolean_type_tree = build_pointer_type(boolean_type_node); + tree is_sends_arg; + + if (i == 0) + { + chans_arg = fold_convert_loc(location, pointer_chan_type_tree, + null_pointer_node); + is_sends_arg = fold_convert_loc(location, pointer_boolean_type_tree, + null_pointer_node); + } + else + { + tree index_type_tree = build_index_type(size_int(count - 1)); + tree chan_array_type_tree = build_array_type(channel_type_tree, + index_type_tree); + tree chan_constructor = build_constructor(chan_array_type_tree, + chan_init); + tree chan_var = create_tmp_var(chan_array_type_tree, "CHAN"); + DECL_IGNORED_P(chan_var) = 0; + DECL_INITIAL(chan_var) = chan_constructor; + DECL_SOURCE_LOCATION(chan_var) = location; + TREE_ADDRESSABLE(chan_var) = 1; + tree decl_expr = build1(DECL_EXPR, void_type_node, chan_var); + SET_EXPR_LOCATION(decl_expr, location); + append_to_statement_list(decl_expr, &final_stmt_list); + + tree is_send_array_type_tree = build_array_type(boolean_type_node, + index_type_tree); + tree is_send_constructor = build_constructor(is_send_array_type_tree, + is_send_init); + tree is_send_var = create_tmp_var(is_send_array_type_tree, "ISSEND"); + DECL_IGNORED_P(is_send_var) = 0; + DECL_INITIAL(is_send_var) = is_send_constructor; + DECL_SOURCE_LOCATION(is_send_var) = location; + TREE_ADDRESSABLE(is_send_var) = 1; + decl_expr = build1(DECL_EXPR, void_type_node, is_send_var); + SET_EXPR_LOCATION(decl_expr, location); + append_to_statement_list(decl_expr, &final_stmt_list); + + chans_arg = fold_convert_loc(location, pointer_chan_type_tree, + build_fold_addr_expr_loc(location, + chan_var)); + is_sends_arg = fold_convert_loc(location, pointer_boolean_type_tree, + build_fold_addr_expr_loc(location, + is_send_var)); + } + + static tree select_fndecl; + tree call = Gogo::call_builtin(&select_fndecl, + location, + "__go_select", + 4, + sizetype, + sizetype, + size_int(count), + boolean_type_node, + (default_clause == NULL + ? boolean_false_node + : boolean_true_node), + pointer_chan_type_tree, + chans_arg, + pointer_boolean_type_tree, + is_sends_arg); + if (call == error_mark_node) + return error_mark_node; + + tree stmt_list = NULL_TREE; + + if (default_clause != NULL) + this->add_clause_tree(context, 0, default_clause, break_label, &stmt_list); + + i = 1; + for (Clauses::iterator p = this->clauses_.begin(); + p != this->clauses_.end(); + ++p) + { + if (!p->is_default()) + { + this->add_clause_tree(context, i, &*p, break_label, &stmt_list); + ++i; + } + } + + append_to_statement_list(break_label->get_definition(), &stmt_list); + + tree switch_stmt = build3(SWITCH_EXPR, sizetype, call, stmt_list, NULL_TREE); + SET_EXPR_LOCATION(switch_stmt, location); + append_to_statement_list(switch_stmt, &final_stmt_list); + + return final_stmt_list; +} + +// Add the tree for CLAUSE to STMT_LIST. + +void +Select_clauses::add_clause_tree(Translate_context* context, int case_index, + Select_clause* clause, + Unnamed_label* bottom_label, tree* stmt_list) +{ + tree label = create_artificial_label(clause->location()); + append_to_statement_list(build3(CASE_LABEL_EXPR, void_type_node, + build_int_cst(sizetype, case_index), + NULL_TREE, label), + stmt_list); + append_to_statement_list(clause->get_statements_tree(context), stmt_list); + tree g = bottom_label->get_goto(clause->statements() == NULL + ? clause->location() + : clause->statements()->end_location()); + append_to_statement_list(g, stmt_list); +} + +// Class Select_statement. + +// Return the break label for this switch statement, creating it if +// necessary. + +Unnamed_label* +Select_statement::break_label() +{ + if (this->break_label_ == NULL) + this->break_label_ = new Unnamed_label(this->location()); + return this->break_label_; +} + +// Lower a select statement. This will still return a select +// statement, but it will be modified to implement the order of +// evaluation rules, and to include the send and receive statements as +// explicit statements in the clauses. + +Statement* +Select_statement::do_lower(Gogo*, Block* enclosing) +{ + if (this->is_lowered_) + return this; + Block* b = new Block(enclosing, this->location()); + this->clauses_->lower(b); + this->is_lowered_ = true; + b->add_statement(this); + return Statement::make_block_statement(b, this->location()); +} + +// Return the tree for a select statement. + +tree +Select_statement::do_get_tree(Translate_context* context) +{ + return this->clauses_->get_tree(context, this->break_label(), + this->location()); +} + +// Make a select statement. + +Select_statement* +Statement::make_select_statement(source_location location) +{ + return new Select_statement(location); +} + +// Class For_statement. + +// Traversal. + +int +For_statement::do_traverse(Traverse* traverse) +{ + if (this->init_ != NULL) + { + if (this->init_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if (this->cond_ != NULL) + { + if (this->traverse_expression(traverse, &this->cond_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if (this->post_ != NULL) + { + if (this->post_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return this->statements_->traverse(traverse); +} + +// Lower a For_statement into if statements and gotos. Getting rid of +// complex statements make it easier to handle garbage collection. + +Statement* +For_statement::do_lower(Gogo*, Block* enclosing) +{ + Statement* s; + source_location loc = this->location(); + + Block* b = new Block(enclosing, this->location()); + if (this->init_ != NULL) + { + s = Statement::make_block_statement(this->init_, + this->init_->start_location()); + b->add_statement(s); + } + + Unnamed_label* entry = NULL; + if (this->cond_ != NULL) + { + entry = new Unnamed_label(this->location()); + b->add_statement(Statement::make_goto_unnamed_statement(entry, loc)); + } + + Unnamed_label* top = new Unnamed_label(this->location()); + b->add_statement(Statement::make_unnamed_label_statement(top)); + + s = Statement::make_block_statement(this->statements_, + this->statements_->start_location()); + b->add_statement(s); + + source_location end_loc = this->statements_->end_location(); + + Unnamed_label* cont = this->continue_label_; + if (cont != NULL) + b->add_statement(Statement::make_unnamed_label_statement(cont)); + + if (this->post_ != NULL) + { + s = Statement::make_block_statement(this->post_, + this->post_->start_location()); + b->add_statement(s); + end_loc = this->post_->end_location(); + } + + if (this->cond_ == NULL) + b->add_statement(Statement::make_goto_unnamed_statement(top, end_loc)); + else + { + b->add_statement(Statement::make_unnamed_label_statement(entry)); + + source_location cond_loc = this->cond_->location(); + Block* then_block = new Block(b, cond_loc); + s = Statement::make_goto_unnamed_statement(top, cond_loc); + then_block->add_statement(s); + + s = Statement::make_if_statement(this->cond_, then_block, NULL, cond_loc); + b->add_statement(s); + } + + Unnamed_label* brk = this->break_label_; + if (brk != NULL) + b->add_statement(Statement::make_unnamed_label_statement(brk)); + + b->set_end_location(end_loc); + + return Statement::make_block_statement(b, loc); +} + +// Return the break label, creating it if necessary. + +Unnamed_label* +For_statement::break_label() +{ + if (this->break_label_ == NULL) + this->break_label_ = new Unnamed_label(this->location()); + return this->break_label_; +} + +// Return the continue LABEL_EXPR. + +Unnamed_label* +For_statement::continue_label() +{ + if (this->continue_label_ == NULL) + this->continue_label_ = new Unnamed_label(this->location()); + return this->continue_label_; +} + +// Set the break and continue labels a for statement. This is used +// when lowering a for range statement. + +void +For_statement::set_break_continue_labels(Unnamed_label* break_label, + Unnamed_label* continue_label) +{ + gcc_assert(this->break_label_ == NULL && this->continue_label_ == NULL); + this->break_label_ = break_label; + this->continue_label_ = continue_label; +} + +// Make a for statement. + +For_statement* +Statement::make_for_statement(Block* init, Expression* cond, Block* post, + source_location location) +{ + return new For_statement(init, cond, post, location); +} + +// Class For_range_statement. + +// Traversal. + +int +For_range_statement::do_traverse(Traverse* traverse) +{ + if (this->traverse_expression(traverse, &this->index_var_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (this->value_var_ != NULL) + { + if (this->traverse_expression(traverse, &this->value_var_) + == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + if (this->traverse_expression(traverse, &this->range_) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return this->statements_->traverse(traverse); +} + +// Lower a for range statement. For simplicity we lower this into a +// for statement, which will then be lowered in turn to goto +// statements. + +Statement* +For_range_statement::do_lower(Gogo* gogo, Block* enclosing) +{ + Type* range_type = this->range_->type(); + if (range_type->points_to() != NULL + && range_type->points_to()->array_type() != NULL + && !range_type->points_to()->is_open_array_type()) + range_type = range_type->points_to(); + + Type* index_type; + Type* value_type = NULL; + if (range_type->array_type() != NULL) + { + index_type = Type::lookup_integer_type("int"); + value_type = range_type->array_type()->element_type(); + } + else if (range_type->is_string_type()) + { + index_type = Type::lookup_integer_type("int"); + value_type = index_type; + } + else if (range_type->map_type() != NULL) + { + index_type = range_type->map_type()->key_type(); + value_type = range_type->map_type()->val_type(); + } + else if (range_type->channel_type() != NULL) + { + index_type = range_type->channel_type()->element_type(); + if (this->value_var_ != NULL) + { + if (!this->value_var_->type()->is_error_type()) + this->report_error(_("too many variables for range clause " + "with channel")); + return Statement::make_error_statement(this->location()); + } + } + else + { + this->report_error(_("range clause must have " + "array, slice, setring, map, or channel type")); + return Statement::make_error_statement(this->location()); + } + + source_location loc = this->location(); + Block* temp_block = new Block(enclosing, loc); + + Named_object* range_object = NULL; + Temporary_statement* range_temp = NULL; + Var_expression* ve = this->range_->var_expression(); + if (ve != NULL) + range_object = ve->named_object(); + else + { + range_temp = Statement::make_temporary(NULL, this->range_, loc); + temp_block->add_statement(range_temp); + } + + Temporary_statement* index_temp = Statement::make_temporary(index_type, + NULL, loc); + temp_block->add_statement(index_temp); + + Temporary_statement* value_temp = NULL; + if (this->value_var_ != NULL) + { + value_temp = Statement::make_temporary(value_type, NULL, loc); + temp_block->add_statement(value_temp); + } + + Block* body = new Block(temp_block, loc); + + Block* init; + Expression* cond; + Block* iter_init; + Block* post; + + // Arrange to do a loop appropriate for the type. We will produce + // for INIT ; COND ; POST { + // ITER_INIT + // INDEX = INDEX_TEMP + // VALUE = VALUE_TEMP // If there is a value + // original statements + // } + + if (range_type->array_type() != NULL) + this->lower_range_array(gogo, temp_block, body, range_object, range_temp, + index_temp, value_temp, &init, &cond, &iter_init, + &post); + else if (range_type->is_string_type()) + this->lower_range_string(gogo, temp_block, body, range_object, range_temp, + index_temp, value_temp, &init, &cond, &iter_init, + &post); + else if (range_type->map_type() != NULL) + this->lower_range_map(gogo, temp_block, body, range_object, range_temp, + index_temp, value_temp, &init, &cond, &iter_init, + &post); + else if (range_type->channel_type() != NULL) + this->lower_range_channel(gogo, temp_block, body, range_object, range_temp, + index_temp, value_temp, &init, &cond, &iter_init, + &post); + else + gcc_unreachable(); + + if (iter_init != NULL) + body->add_statement(Statement::make_block_statement(iter_init, loc)); + + Statement* assign; + Expression* index_ref = Expression::make_temporary_reference(index_temp, loc); + if (this->value_var_ == NULL) + { + assign = Statement::make_assignment(this->index_var_, index_ref, loc); + } + else + { + Expression_list* lhs = new Expression_list(); + lhs->push_back(this->index_var_); + lhs->push_back(this->value_var_); + + Expression_list* rhs = new Expression_list(); + rhs->push_back(index_ref); + rhs->push_back(Expression::make_temporary_reference(value_temp, loc)); + + assign = Statement::make_tuple_assignment(lhs, rhs, loc); + } + body->add_statement(assign); + + body->add_statement(Statement::make_block_statement(this->statements_, loc)); + + body->set_end_location(this->statements_->end_location()); + + For_statement* loop = Statement::make_for_statement(init, cond, post, + this->location()); + loop->add_statements(body); + loop->set_break_continue_labels(this->break_label_, this->continue_label_); + + temp_block->add_statement(loop); + + return Statement::make_block_statement(temp_block, loc); +} + +// Return a reference to the range, which may be in RANGE_OBJECT or in +// RANGE_TEMP. + +Expression* +For_range_statement::make_range_ref(Named_object* range_object, + Temporary_statement* range_temp, + source_location loc) +{ + if (range_object != NULL) + return Expression::make_var_reference(range_object, loc); + else + return Expression::make_temporary_reference(range_temp, loc); +} + +// Return a call to the predeclared function FUNCNAME passing a +// reference to the temporary variable ARG. + +Expression* +For_range_statement::call_builtin(Gogo* gogo, const char* funcname, + Expression* arg, + source_location loc) +{ + Named_object* no = gogo->lookup_global(funcname); + gcc_assert(no != NULL && no->is_function_declaration()); + Expression* func = Expression::make_func_reference(no, NULL, loc); + Expression_list* params = new Expression_list(); + params->push_back(arg); + return Expression::make_call(func, params, false, loc); +} + +// Lower a for range over an array or slice. + +void +For_range_statement::lower_range_array(Gogo* gogo, + Block* enclosing, + Block* body_block, + Named_object* range_object, + Temporary_statement* range_temp, + Temporary_statement* index_temp, + Temporary_statement* value_temp, + Block** pinit, + Expression** pcond, + Block** piter_init, + Block** ppost) +{ + source_location loc = this->location(); + + // The loop we generate: + // len_temp := len(range) + // for index_temp = 0; index_temp < len_temp; index_temp++ { + // value_temp = range[index_temp] + // index = index_temp + // value = value_temp + // original body + // } + + // Set *PINIT to + // var len_temp int + // len_temp = len(range) + // index_temp = 0 + + Block* init = new Block(enclosing, loc); + + Expression* ref = this->make_range_ref(range_object, range_temp, loc); + Expression* len_call = this->call_builtin(gogo, "len", ref, loc); + Temporary_statement* len_temp = Statement::make_temporary(index_temp->type(), + len_call, loc); + init->add_statement(len_temp); + + mpz_t zval; + mpz_init_set_ui(zval, 0UL); + Expression* zexpr = Expression::make_integer(&zval, NULL, loc); + mpz_clear(zval); + + ref = Expression::make_temporary_reference(index_temp, loc); + Statement* s = Statement::make_assignment(ref, zexpr, loc); + init->add_statement(s); + + *pinit = init; + + // Set *PCOND to + // index_temp < len_temp + + ref = Expression::make_temporary_reference(index_temp, loc); + Expression* ref2 = Expression::make_temporary_reference(len_temp, loc); + Expression* lt = Expression::make_binary(OPERATOR_LT, ref, ref2, loc); + + *pcond = lt; + + // Set *PITER_INIT to + // value_temp = range[index_temp] + + Block* iter_init = NULL; + if (value_temp != NULL) + { + iter_init = new Block(body_block, loc); + + ref = this->make_range_ref(range_object, range_temp, loc); + Expression* ref2 = Expression::make_temporary_reference(index_temp, loc); + Expression* index = Expression::make_index(ref, ref2, NULL, loc); + + ref = Expression::make_temporary_reference(value_temp, loc); + s = Statement::make_assignment(ref, index, loc); + + iter_init->add_statement(s); + } + *piter_init = iter_init; + + // Set *PPOST to + // index_temp++ + + Block* post = new Block(enclosing, loc); + ref = Expression::make_temporary_reference(index_temp, loc); + s = Statement::make_inc_statement(ref); + post->add_statement(s); + *ppost = post; +} + +// Lower a for range over a string. + +void +For_range_statement::lower_range_string(Gogo* gogo, + Block* enclosing, + Block* body_block, + Named_object* range_object, + Temporary_statement* range_temp, + Temporary_statement* index_temp, + Temporary_statement* value_temp, + Block** pinit, + Expression** pcond, + Block** piter_init, + Block** ppost) +{ + source_location loc = this->location(); + + // The loop we generate: + // var next_index_temp int + // for index_temp = 0; ; index_temp = next_index_temp { + // next_index_temp, value_temp = stringiter2(range, index_temp) + // if next_index_temp == 0 { + // break + // } + // index = index_temp + // value = value_temp + // original body + // } + + // Set *PINIT to + // var next_index_temp int + // index_temp = 0 + + Block* init = new Block(enclosing, loc); + + Temporary_statement* next_index_temp = + Statement::make_temporary(index_temp->type(), NULL, loc); + init->add_statement(next_index_temp); + + mpz_t zval; + mpz_init_set_ui(zval, 0UL); + Expression* zexpr = Expression::make_integer(&zval, NULL, loc); + + Expression* ref = Expression::make_temporary_reference(index_temp, loc); + Statement* s = Statement::make_assignment(ref, zexpr, loc); + + init->add_statement(s); + *pinit = init; + + // The loop has no condition. + + *pcond = NULL; + + // Set *PITER_INIT to + // next_index_temp = runtime.stringiter(range, index_temp) + // or + // next_index_temp, value_temp = runtime.stringiter2(range, index_temp) + // followed by + // if next_index_temp == 0 { + // break + // } + + Block* iter_init = new Block(body_block, loc); + + Named_object* no; + if (value_temp == NULL) + { + static Named_object* stringiter; + if (stringiter == NULL) + { + source_location bloc = BUILTINS_LOCATION; + Type* int_type = gogo->lookup_global("int")->type_value(); + + Typed_identifier_list* params = new Typed_identifier_list(); + params->push_back(Typed_identifier("s", Type::make_string_type(), + bloc)); + params->push_back(Typed_identifier("k", int_type, bloc)); + + Typed_identifier_list* results = new Typed_identifier_list(); + results->push_back(Typed_identifier("", int_type, bloc)); + + Function_type* fntype = Type::make_function_type(NULL, params, + results, bloc); + stringiter = Named_object::make_function_declaration("stringiter", + NULL, fntype, + bloc); + const char* n = "runtime.stringiter"; + stringiter->func_declaration_value()->set_asm_name(n); + } + no = stringiter; + } + else + { + static Named_object* stringiter2; + if (stringiter2 == NULL) + { + source_location bloc = BUILTINS_LOCATION; + Type* int_type = gogo->lookup_global("int")->type_value(); + + Typed_identifier_list* params = new Typed_identifier_list(); + params->push_back(Typed_identifier("s", Type::make_string_type(), + bloc)); + params->push_back(Typed_identifier("k", int_type, bloc)); + + Typed_identifier_list* results = new Typed_identifier_list(); + results->push_back(Typed_identifier("", int_type, bloc)); + results->push_back(Typed_identifier("", int_type, bloc)); + + Function_type* fntype = Type::make_function_type(NULL, params, + results, bloc); + stringiter2 = Named_object::make_function_declaration("stringiter", + NULL, fntype, + bloc); + const char* n = "runtime.stringiter2"; + stringiter2->func_declaration_value()->set_asm_name(n); + } + no = stringiter2; + } + + Expression* func = Expression::make_func_reference(no, NULL, loc); + Expression_list* params = new Expression_list(); + params->push_back(this->make_range_ref(range_object, range_temp, loc)); + params->push_back(Expression::make_temporary_reference(index_temp, loc)); + Call_expression* call = Expression::make_call(func, params, false, loc); + + if (value_temp == NULL) + { + ref = Expression::make_temporary_reference(next_index_temp, loc); + s = Statement::make_assignment(ref, call, loc); + } + else + { + Expression_list* lhs = new Expression_list(); + lhs->push_back(Expression::make_temporary_reference(next_index_temp, + loc)); + lhs->push_back(Expression::make_temporary_reference(value_temp, loc)); + + Expression_list* rhs = new Expression_list(); + rhs->push_back(Expression::make_call_result(call, 0)); + rhs->push_back(Expression::make_call_result(call, 1)); + + s = Statement::make_tuple_assignment(lhs, rhs, loc); + } + iter_init->add_statement(s); + + ref = Expression::make_temporary_reference(next_index_temp, loc); + zexpr = Expression::make_integer(&zval, NULL, loc); + mpz_clear(zval); + Expression* equals = Expression::make_binary(OPERATOR_EQEQ, ref, zexpr, loc); + + Block* then_block = new Block(iter_init, loc); + s = Statement::make_break_statement(this->break_label(), loc); + then_block->add_statement(s); + + s = Statement::make_if_statement(equals, then_block, NULL, loc); + iter_init->add_statement(s); + + *piter_init = iter_init; + + // Set *PPOST to + // index_temp = next_index_temp + + Block* post = new Block(enclosing, loc); + + Expression* lhs = Expression::make_temporary_reference(index_temp, loc); + Expression* rhs = Expression::make_temporary_reference(next_index_temp, loc); + s = Statement::make_assignment(lhs, rhs, loc); + + post->add_statement(s); + *ppost = post; +} + +// Lower a for range over a map. + +void +For_range_statement::lower_range_map(Gogo* gogo, + Block* enclosing, + Block* body_block, + Named_object* range_object, + Temporary_statement* range_temp, + Temporary_statement* index_temp, + Temporary_statement* value_temp, + Block** pinit, + Expression** pcond, + Block** piter_init, + Block** ppost) +{ + source_location loc = this->location(); + + // The runtime uses a struct to handle ranges over a map. The + // struct is four pointers long. The first pointer is NULL when we + // have completed the iteration. + + // The loop we generate: + // var hiter map_iteration_struct + // for mapiterinit(range, &hiter); hiter[0] != nil; mapiternext(&hiter) { + // mapiter2(hiter, &index_temp, &value_temp) + // index = index_temp + // value = value_temp + // original body + // } + + // Set *PINIT to + // var hiter map_iteration_struct + // runtime.mapiterinit(range, &hiter) + + Block* init = new Block(enclosing, loc); + + const unsigned long map_iteration_size = 4; + + mpz_t ival; + mpz_init_set_ui(ival, map_iteration_size); + Expression* iexpr = Expression::make_integer(&ival, NULL, loc); + mpz_clear(ival); + + Type* byte_type = gogo->lookup_global("byte")->type_value(); + Type* ptr_type = Type::make_pointer_type(byte_type); + + Type* map_iteration_type = Type::make_array_type(ptr_type, iexpr); + Type* map_iteration_ptr = Type::make_pointer_type(map_iteration_type); + + Temporary_statement* hiter = Statement::make_temporary(map_iteration_type, + NULL, loc); + init->add_statement(hiter); + + source_location bloc = BUILTINS_LOCATION; + Typed_identifier_list* param_types = new Typed_identifier_list(); + param_types->push_back(Typed_identifier("map", this->range_->type(), bloc)); + param_types->push_back(Typed_identifier("it", map_iteration_ptr, bloc)); + Function_type* fntype = Type::make_function_type(NULL, param_types, NULL, + bloc); + + Named_object* mapiterinit = + Named_object::make_function_declaration("mapiterinit", NULL, fntype, bloc); + const char* n = "runtime.mapiterinit"; + mapiterinit->func_declaration_value()->set_asm_name(n); + + Expression* func = Expression::make_func_reference(mapiterinit, NULL, loc); + Expression_list* params = new Expression_list(); + params->push_back(this->make_range_ref(range_object, range_temp, loc)); + Expression* ref = Expression::make_temporary_reference(hiter, loc); + params->push_back(Expression::make_unary(OPERATOR_AND, ref, loc)); + Expression* call = Expression::make_call(func, params, false, loc); + init->add_statement(Statement::make_statement(call)); + + *pinit = init; + + // Set *PCOND to + // hiter[0] != nil + + ref = Expression::make_temporary_reference(hiter, loc); + + mpz_t zval; + mpz_init_set_ui(zval, 0UL); + Expression* zexpr = Expression::make_integer(&zval, NULL, loc); + mpz_clear(zval); + + Expression* index = Expression::make_index(ref, zexpr, NULL, loc); + + Expression* ne = Expression::make_binary(OPERATOR_NOTEQ, index, + Expression::make_nil(loc), + loc); + + *pcond = ne; + + // Set *PITER_INIT to + // mapiter1(hiter, &index_temp) + // or + // mapiter2(hiter, &index_temp, &value_temp) + + Block* iter_init = new Block(body_block, loc); + + param_types = new Typed_identifier_list(); + param_types->push_back(Typed_identifier("hiter", map_iteration_ptr, bloc)); + Type* pkey_type = Type::make_pointer_type(index_temp->type()); + param_types->push_back(Typed_identifier("key", pkey_type, bloc)); + if (value_temp != NULL) + { + Type* pval_type = Type::make_pointer_type(value_temp->type()); + param_types->push_back(Typed_identifier("val", pval_type, bloc)); + } + fntype = Type::make_function_type(NULL, param_types, NULL, bloc); + n = value_temp == NULL ? "mapiter1" : "mapiter2"; + Named_object* mapiter = Named_object::make_function_declaration(n, NULL, + fntype, bloc); + n = value_temp == NULL ? "runtime.mapiter1" : "runtime.mapiter2"; + mapiter->func_declaration_value()->set_asm_name(n); + + func = Expression::make_func_reference(mapiter, NULL, loc); + params = new Expression_list(); + ref = Expression::make_temporary_reference(hiter, loc); + params->push_back(Expression::make_unary(OPERATOR_AND, ref, loc)); + ref = Expression::make_temporary_reference(index_temp, loc); + params->push_back(Expression::make_unary(OPERATOR_AND, ref, loc)); + if (value_temp != NULL) + { + ref = Expression::make_temporary_reference(value_temp, loc); + params->push_back(Expression::make_unary(OPERATOR_AND, ref, loc)); + } + call = Expression::make_call(func, params, false, loc); + iter_init->add_statement(Statement::make_statement(call)); + + *piter_init = iter_init; + + // Set *PPOST to + // mapiternext(&hiter) + + Block* post = new Block(enclosing, loc); + + static Named_object* mapiternext; + if (mapiternext == NULL) + { + param_types = new Typed_identifier_list(); + param_types->push_back(Typed_identifier("it", map_iteration_ptr, bloc)); + fntype = Type::make_function_type(NULL, param_types, NULL, bloc); + mapiternext = Named_object::make_function_declaration("mapiternext", + NULL, fntype, + bloc); + const char* n = "runtime.mapiternext"; + mapiternext->func_declaration_value()->set_asm_name(n); + } + + func = Expression::make_func_reference(mapiternext, NULL, loc); + params = new Expression_list(); + ref = Expression::make_temporary_reference(hiter, loc); + params->push_back(Expression::make_unary(OPERATOR_AND, ref, loc)); + call = Expression::make_call(func, params, false, loc); + post->add_statement(Statement::make_statement(call)); + + *ppost = post; +} + +// Lower a for range over a channel. + +void +For_range_statement::lower_range_channel(Gogo* gogo, + Block*, + Block* body_block, + Named_object* range_object, + Temporary_statement* range_temp, + Temporary_statement* index_temp, + Temporary_statement* value_temp, + Block** pinit, + Expression** pcond, + Block** piter_init, + Block** ppost) +{ + gcc_assert(value_temp == NULL); + + source_location loc = this->location(); + + // The loop we generate: + // for { + // index_temp = <-range + // if closed(range) { + // break + // } + // index = index_temp + // value = value_temp + // original body + // } + + // We have no initialization code, no condition, and no post code. + + *pinit = NULL; + *pcond = NULL; + *ppost = NULL; + + // Set *PITER_INIT to + // index_temp = <-range + // if closed(range) { + // break + // } + + Block* iter_init = new Block(body_block, loc); + + Expression* ref = this->make_range_ref(range_object, range_temp, loc); + Expression* cond = this->call_builtin(gogo, "closed", ref, loc); + + ref = this->make_range_ref(range_object, range_temp, loc); + Expression* recv = Expression::make_receive(ref, loc); + ref = Expression::make_temporary_reference(index_temp, loc); + Statement* s = Statement::make_assignment(ref, recv, loc); + iter_init->add_statement(s); + + Block* then_block = new Block(iter_init, loc); + s = Statement::make_break_statement(this->break_label(), loc); + then_block->add_statement(s); + + s = Statement::make_if_statement(cond, then_block, NULL, loc); + iter_init->add_statement(s); + + *piter_init = iter_init; +} + +// Return the break LABEL_EXPR. + +Unnamed_label* +For_range_statement::break_label() +{ + if (this->break_label_ == NULL) + this->break_label_ = new Unnamed_label(this->location()); + return this->break_label_; +} + +// Return the continue LABEL_EXPR. + +Unnamed_label* +For_range_statement::continue_label() +{ + if (this->continue_label_ == NULL) + this->continue_label_ = new Unnamed_label(this->location()); + return this->continue_label_; +} + +// Make a for statement with a range clause. + +For_range_statement* +Statement::make_for_range_statement(Expression* index_var, + Expression* value_var, + Expression* range, + source_location location) +{ + return new For_range_statement(index_var, value_var, range, location); +} diff --git a/gcc/go/gofrontend/statements.h b/gcc/go/gofrontend/statements.h new file mode 100644 index 000000000..80cdffe80 --- /dev/null +++ b/gcc/go/gofrontend/statements.h @@ -0,0 +1,1416 @@ +// statements.h -- Go frontend statements. -*- C++ -*- + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef GO_STATEMENTS_H +#define GO_STATEMENTS_H + +#include "operator.h" + +class Gogo; +class Traverse; +class Block; +class Function; +class Unnamed_label; +class Temporary_statement; +class Variable_declaration_statement; +class Return_statement; +class Thunk_statement; +class Label_statement; +class For_statement; +class For_range_statement; +class Switch_statement; +class Type_switch_statement; +class Select_statement; +class Variable; +class Named_object; +class Label; +class Translate_context; +class Expression; +class Expression_list; +class Struct_type; +class Call_expression; +class Map_index_expression; +class Receive_expression; +class Case_clauses; +class Type_case_clauses; +class Select_clauses; +class Typed_identifier_list; + +// This class is used to traverse assignments made by a statement +// which makes assignments. + +class Traverse_assignments +{ + public: + Traverse_assignments() + { } + + virtual ~Traverse_assignments() + { } + + // This is called for a variable initialization. + virtual void + initialize_variable(Named_object*) = 0; + + // This is called for each assignment made by the statement. PLHS + // points to the left hand side, and PRHS points to the right hand + // side. PRHS may be NULL if there is no associated expression, as + // in the bool set by a non-blocking receive. + virtual void + assignment(Expression** plhs, Expression** prhs) = 0; + + // This is called for each expression which is not passed to the + // assignment function. This is used for some of the statements + // which assign two values, for which there is no expression which + // describes the value. For ++ and -- the value is passed to both + // the assignment method and the rhs method. IS_STORED is true if + // this value is being stored directly. It is false if the value is + // computed but not stored. IS_LOCAL is true if the value is being + // stored in a local variable or this is being called by a return + // statement. + virtual void + value(Expression**, bool is_stored, bool is_local) = 0; +}; + +// A single statement. + +class Statement +{ + public: + // The types of statements. + enum Statement_classification + { + STATEMENT_ERROR, + STATEMENT_VARIABLE_DECLARATION, + STATEMENT_TEMPORARY, + STATEMENT_ASSIGNMENT, + STATEMENT_EXPRESSION, + STATEMENT_BLOCK, + STATEMENT_GO, + STATEMENT_DEFER, + STATEMENT_RETURN, + STATEMENT_BREAK_OR_CONTINUE, + STATEMENT_GOTO, + STATEMENT_GOTO_UNNAMED, + STATEMENT_LABEL, + STATEMENT_UNNAMED_LABEL, + STATEMENT_IF, + STATEMENT_CONSTANT_SWITCH, + STATEMENT_SELECT, + + // These statements types are created by the parser, but they + // disappear during the lowering pass. + STATEMENT_ASSIGNMENT_OPERATION, + STATEMENT_TUPLE_ASSIGNMENT, + STATEMENT_TUPLE_MAP_ASSIGNMENT, + STATEMENT_MAP_ASSIGNMENT, + STATEMENT_TUPLE_RECEIVE_ASSIGNMENT, + STATEMENT_TUPLE_TYPE_GUARD_ASSIGNMENT, + STATEMENT_INCDEC, + STATEMENT_FOR, + STATEMENT_FOR_RANGE, + STATEMENT_SWITCH, + STATEMENT_TYPE_SWITCH + }; + + Statement(Statement_classification, source_location); + + virtual ~Statement(); + + // Make a variable declaration. + static Statement* + make_variable_declaration(Named_object*); + + // Make a statement which creates a temporary variable and + // initializes it to an expression. The block is used if the + // temporary variable has to be explicitly destroyed; the variable + // must still be added to the block. References to the temporary + // variable may be constructed using make_temporary_reference. + // Either the type or the initialization expression may be NULL, but + // not both. + static Temporary_statement* + make_temporary(Type*, Expression*, source_location); + + // Make an assignment statement. + static Statement* + make_assignment(Expression*, Expression*, source_location); + + // Make an assignment operation (+=, etc.). + static Statement* + make_assignment_operation(Operator, Expression*, Expression*, + source_location); + + // Make a tuple assignment statement. + static Statement* + make_tuple_assignment(Expression_list*, Expression_list*, source_location); + + // Make an assignment from a map index to a pair of variables. + static Statement* + make_tuple_map_assignment(Expression* val, Expression* present, + Expression*, source_location); + + // Make a statement which assigns a pair of values to a map. + static Statement* + make_map_assignment(Expression*, Expression* val, + Expression* should_set, source_location); + + // Make an assignment from a nonblocking receive to a pair of + // variables. + static Statement* + make_tuple_receive_assignment(Expression* val, Expression* success, + Expression* channel, source_location); + + // Make an assignment from a type guard to a pair of variables. + static Statement* + make_tuple_type_guard_assignment(Expression* val, Expression* ok, + Expression* expr, Type* type, + source_location); + + // Make an expression statement from an Expression. + static Statement* + make_statement(Expression*); + + // Make a block statement from a Block. This is an embedded list of + // statements which may also include variable definitions. + static Statement* + make_block_statement(Block*, source_location); + + // Make an increment statement. + static Statement* + make_inc_statement(Expression*); + + // Make a decrement statement. + static Statement* + make_dec_statement(Expression*); + + // Make a go statement. + static Statement* + make_go_statement(Call_expression* call, source_location); + + // Make a defer statement. + static Statement* + make_defer_statement(Call_expression* call, source_location); + + // Make a return statement. + static Statement* + make_return_statement(const Typed_identifier_list*, Expression_list*, + source_location); + + // Make a break statement. + static Statement* + make_break_statement(Unnamed_label* label, source_location); + + // Make a continue statement. + static Statement* + make_continue_statement(Unnamed_label* label, source_location); + + // Make a goto statement. + static Statement* + make_goto_statement(Label* label, source_location); + + // Make a goto statement to an unnamed label. + static Statement* + make_goto_unnamed_statement(Unnamed_label* label, source_location); + + // Make a label statement--where the label is defined. + static Statement* + make_label_statement(Label* label, source_location); + + // Make an unnamed label statement--where the label is defined. + static Statement* + make_unnamed_label_statement(Unnamed_label* label); + + // Make an if statement. + static Statement* + make_if_statement(Expression* cond, Block* then_block, Block* else_block, + source_location); + + // Make a switch statement. + static Switch_statement* + make_switch_statement(Expression* switch_val, source_location); + + // Make a type switch statement. + static Type_switch_statement* + make_type_switch_statement(Named_object* var, Expression*, source_location); + + // Make a select statement. + static Select_statement* + make_select_statement(source_location); + + // Make a for statement. + static For_statement* + make_for_statement(Block* init, Expression* cond, Block* post, + source_location location); + + // Make a for statement with a range clause. + static For_range_statement* + make_for_range_statement(Expression* index_var, Expression* value_var, + Expression* range, source_location); + + // Return the statement classification. + Statement_classification + classification() const + { return this->classification_; } + + // Get the statement location. + source_location + location() const + { return this->location_; } + + // Traverse the tree. + int + traverse(Block*, size_t* index, Traverse*); + + // Traverse the contents of this statement--the expressions and + // statements which it contains. + int + traverse_contents(Traverse*); + + // If this statement assigns some values, it calls a function for + // each value to which this statement assigns a value, and returns + // true. If this statement does not assign any values, it returns + // false. + bool + traverse_assignments(Traverse_assignments* tassign); + + // Lower a statement. This is called immediately after parsing to + // simplify statements for further processing. It returns the same + // Statement or a new one. BLOCK is the block containing this + // statement. + Statement* + lower(Gogo* gogo, Block* block) + { return this->do_lower(gogo, block); } + + // Set type information for unnamed constants. + void + determine_types(); + + // Check types in a statement. This simply checks that any + // expressions used by the statement have the right type. + void + check_types(Gogo* gogo) + { this->do_check_types(gogo); } + + // Return whether this is a block statement. + bool + is_block_statement() const + { return this->classification_ == STATEMENT_BLOCK; } + + // If this is a variable declaration statement, return it. + // Otherwise return NULL. + Variable_declaration_statement* + variable_declaration_statement() + { + return this->convert<Variable_declaration_statement, + STATEMENT_VARIABLE_DECLARATION>(); + } + + // If this is a return statement, return it. Otherwise return NULL. + Return_statement* + return_statement() + { return this->convert<Return_statement, STATEMENT_RETURN>(); } + + // If this is a thunk statement (a go or defer statement), return + // it. Otherwise return NULL. + Thunk_statement* + thunk_statement(); + + // If this is a label statement, return it. Otherwise return NULL. + Label_statement* + label_statement() + { return this->convert<Label_statement, STATEMENT_LABEL>(); } + + // If this is a for statement, return it. Otherwise return NULL. + For_statement* + for_statement() + { return this->convert<For_statement, STATEMENT_FOR>(); } + + // If this is a for statement over a range clause, return it. + // Otherwise return NULL. + For_range_statement* + for_range_statement() + { return this->convert<For_range_statement, STATEMENT_FOR_RANGE>(); } + + // If this is a switch statement, return it. Otherwise return NULL. + Switch_statement* + switch_statement() + { return this->convert<Switch_statement, STATEMENT_SWITCH>(); } + + // If this is a type switch statement, return it. Otherwise return + // NULL. + Type_switch_statement* + type_switch_statement() + { return this->convert<Type_switch_statement, STATEMENT_TYPE_SWITCH>(); } + + // If this is a select statement, return it. Otherwise return NULL. + Select_statement* + select_statement() + { return this->convert<Select_statement, STATEMENT_SELECT>(); } + + // Return true if this statement may fall through--if after + // executing this statement we may go on to execute the following + // statement, if any. + bool + may_fall_through() const + { return this->do_may_fall_through(); } + + // Return the tree for a statement. BLOCK is the enclosing block. + tree + get_tree(Translate_context*); + + protected: + // Implemented by child class: traverse the tree. + virtual int + do_traverse(Traverse*) = 0; + + // Implemented by child class: traverse assignments. Any statement + // which includes an assignment should implement this. + virtual bool + do_traverse_assignments(Traverse_assignments*) + { return false; } + + // Implemented by the child class: lower this statement to a simpler + // one. + virtual Statement* + do_lower(Gogo*, Block*) + { return this; } + + // Implemented by child class: set type information for unnamed + // constants. Any statement which includes an expression needs to + // implement this. + virtual void + do_determine_types() + { } + + // Implemented by child class: check types of expressions used in a + // statement. + virtual void + do_check_types(Gogo*) + { } + + // Implemented by child class: return true if this statement may + // fall through. + virtual bool + do_may_fall_through() const + { return true; } + + // Implemented by child class: return a tree. + virtual tree + do_get_tree(Translate_context*) = 0; + + // Traverse an expression in a statement. + int + traverse_expression(Traverse*, Expression**); + + // Traverse an expression list in a statement. The Expression_list + // may be NULL. + int + traverse_expression_list(Traverse*, Expression_list*); + + // Traverse a type in a statement. + int + traverse_type(Traverse*, Type*); + + // Build a tree node with one operand, setting the location. The + // first operand really has type "enum tree_code", but that enum is + // not defined here. + tree + build_stmt_1(int tree_code_value, tree); + + // For children to call when they detect that they are in error. + void + set_is_error(); + + // For children to call to report an error conveniently. + void + report_error(const char*); + + // For children to return an error statement from lower(). + static Statement* + make_error_statement(source_location); + + private: + // Convert to the desired statement classification, or return NULL. + // This is a controlled dynamic cast. + template<typename Statement_class, Statement_classification sc> + Statement_class* + convert() + { + return (this->classification_ == sc + ? static_cast<Statement_class*>(this) + : NULL); + } + + template<typename Statement_class, Statement_classification sc> + const Statement_class* + convert() const + { + return (this->classification_ == sc + ? static_cast<const Statement_class*>(this) + : NULL); + } + + // The statement classification. + Statement_classification classification_; + // The location in the input file of the start of this statement. + source_location location_; +}; + +// A statement which creates and initializes a temporary variable. + +class Temporary_statement : public Statement +{ + public: + Temporary_statement(Type* type, Expression* init, source_location location) + : Statement(STATEMENT_TEMPORARY, location), + type_(type), init_(init), decl_(NULL), is_address_taken_(false) + { } + + // Return the type of the temporary variable. + Type* + type() const; + + // Return the initialization expression. + Expression* + init() const + { return this->init_; } + + // Record that something takes the address of this temporary + // variable. + void + set_is_address_taken() + { this->is_address_taken_ = true; } + + // Return the tree for the temporary variable itself. This should + // not be called until after the statement itself has been expanded. + tree + get_decl() const; + + protected: + int + do_traverse(Traverse*); + + bool + do_traverse_assignments(Traverse_assignments*); + + void + do_determine_types(); + + void + do_check_types(Gogo*); + + tree + do_get_tree(Translate_context*); + + private: + // The type of the temporary variable. + Type* type_; + // The initial value of the temporary variable. This may be NULL. + Expression* init_; + // The DECL for the temporary variable. + tree decl_; + // True if something takes the address of this temporary variable. + bool is_address_taken_; +}; + +// A variable declaration. This marks the point in the code where a +// variable is declared. The Variable is also attached to a Block. + +class Variable_declaration_statement : public Statement +{ + public: + Variable_declaration_statement(Named_object* var); + + // The variable being declared. + Named_object* + var() + { return this->var_; } + + protected: + int + do_traverse(Traverse*); + + bool + do_traverse_assignments(Traverse_assignments*); + + tree + do_get_tree(Translate_context*); + + private: + Named_object* var_; +}; + +// A return statement. + +class Return_statement : public Statement +{ + public: + Return_statement(const Typed_identifier_list* results, Expression_list* vals, + source_location location) + : Statement(STATEMENT_RETURN, location), + results_(results), vals_(vals) + { } + + // The list of values being returned. This may be NULL. + const Expression_list* + vals() const + { return this->vals_; } + + protected: + int + do_traverse(Traverse* traverse) + { return this->traverse_expression_list(traverse, this->vals_); } + + bool + do_traverse_assignments(Traverse_assignments*); + + Statement* + do_lower(Gogo*, Block*); + + void + do_determine_types(); + + void + do_check_types(Gogo*); + + bool + do_may_fall_through() const + { return false; } + + tree + do_get_tree(Translate_context*); + + private: + // The result types of the function we are returning from. This is + // here because in some of the traversals it is inconvenient to get + // it. + const Typed_identifier_list* results_; + // Return values. This may be NULL. + Expression_list* vals_; +}; + +// Select_clauses holds the clauses of a select statement. This is +// built by the parser. + +class Select_clauses +{ + public: + Select_clauses() + : clauses_() + { } + + // Add a new clause. IS_SEND is true if this is a send clause, + // false for a receive clause. For a send clause CHANNEL is the + // channel and VAL is the value to send. For a receive clause + // CHANNEL is the channel and VAL is either NULL or a Var_expression + // for the variable to set; if VAL is NULL, VAR may be a variable + // which is initialized with the received value. IS_DEFAULT is true + // if this is the default clause. STATEMENTS is the list of + // statements to execute. + void + add(bool is_send, Expression* channel, Expression* val, Named_object* var, + bool is_default, Block* statements, source_location location) + { + this->clauses_.push_back(Select_clause(is_send, channel, val, var, + is_default, statements, location)); + } + + // Traverse the select clauses. + int + traverse(Traverse*); + + // Lower statements. + void + lower(Block*); + + // Determine types. + void + determine_types(); + + // Whether the select clauses may fall through to the statement + // which follows the overall select statement. + bool + may_fall_through() const; + + // Return a tree implementing the select statement. + tree + get_tree(Translate_context*, Unnamed_label* break_label, source_location); + + private: + // A single clause. + class Select_clause + { + public: + Select_clause() + : channel_(NULL), val_(NULL), var_(NULL), statements_(NULL), + is_send_(false), is_default_(false) + { } + + Select_clause(bool is_send, Expression* channel, Expression* val, + Named_object* var, bool is_default, Block* statements, + source_location location) + : channel_(channel), val_(val), var_(var), statements_(statements), + location_(location), is_send_(is_send), is_default_(is_default), + is_lowered_(false) + { gcc_assert(is_default ? channel == NULL : channel != NULL); } + + // Traverse the select clause. + int + traverse(Traverse*); + + // Lower statements. + void + lower(Block*); + + // Determine types. + void + determine_types(); + + // Return true if this is the default clause. + bool + is_default() const + { return this->is_default_; } + + // Return the channel. This will return NULL for the default + // clause. + Expression* + channel() const + { return this->channel_; } + + // Return the value. This will return NULL for the default + // clause, or for a receive clause for which no value was given. + Expression* + val() const + { return this->val_; } + + // Return the variable to set when a receive clause is also a + // variable definition (v := <- ch). This will return NULL for + // the default case, or for a send clause, or for a receive clause + // which does not define a variable. + Named_object* + var() const + { return this->var_; } + + // Return true for a send, false for a receive. + bool + is_send() const + { + gcc_assert(!this->is_default_); + return this->is_send_; + } + + // Return the statements. + const Block* + statements() const + { return this->statements_; } + + // Return the location. + source_location + location() const + { return this->location_; } + + // Whether this clause may fall through to the statement which + // follows the overall select statement. + bool + may_fall_through() const; + + // Return a tree for the statements to execute. + tree + get_statements_tree(Translate_context*); + + private: + // The channel. + Expression* channel_; + // The value to send or the variable to set. + Expression* val_; + // The variable to initialize, for "case a := <- ch". + Named_object* var_; + // The statements to execute. + Block* statements_; + // The location of this clause. + source_location location_; + // Whether this is a send or a receive. + bool is_send_; + // Whether this is the default. + bool is_default_; + // Whether this has been lowered. + bool is_lowered_; + }; + + void + add_clause_tree(Translate_context*, int, Select_clause*, Unnamed_label*, + tree*); + + typedef std::vector<Select_clause> Clauses; + + Clauses clauses_; +}; + +// A select statement. + +class Select_statement : public Statement +{ + public: + Select_statement(source_location location) + : Statement(STATEMENT_SELECT, location), + clauses_(NULL), break_label_(NULL), is_lowered_(false) + { } + + // Add the clauses. + void + add_clauses(Select_clauses* clauses) + { + gcc_assert(this->clauses_ == NULL); + this->clauses_ = clauses; + } + + // Return the break label for this select statement. + Unnamed_label* + break_label(); + + protected: + int + do_traverse(Traverse* traverse) + { return this->clauses_->traverse(traverse); } + + Statement* + do_lower(Gogo*, Block*); + + void + do_determine_types() + { this->clauses_->determine_types(); } + + bool + do_may_fall_through() const + { return this->clauses_->may_fall_through(); } + + tree + do_get_tree(Translate_context*); + + private: + // The select clauses. + Select_clauses* clauses_; + // The break label. + Unnamed_label* break_label_; + // Whether this statement has been lowered. + bool is_lowered_; +}; + +// A statement which requires a thunk: go or defer. + +class Thunk_statement : public Statement +{ + public: + Thunk_statement(Statement_classification, Call_expression*, + source_location); + + // Return the call expression. + Expression* + call() + { return this->call_; } + + // Simplify a go or defer statement so that it only uses a single + // parameter. + bool + simplify_statement(Gogo*, Block*); + + protected: + int + do_traverse(Traverse* traverse); + + bool + do_traverse_assignments(Traverse_assignments*); + + void + do_determine_types(); + + void + do_check_types(Gogo*); + + // Return the function and argument trees for the call. + void + get_fn_and_arg(Translate_context*, tree* pfn, tree* parg); + + private: + // Return whether this is a simple go statement. + bool + is_simple(Function_type*) const; + + // Build the struct to use for a complex case. + Struct_type* + build_struct(Function_type* fntype); + + // Build the thunk. + void + build_thunk(Gogo*, const std::string&, Function_type* fntype); + + // The field name used in the thunk structure for the function + // pointer. + static const char* const thunk_field_fn; + + // The field name used in the thunk structure for the receiver, if + // there is one. + static const char* const thunk_field_receiver; + + // Set the name to use for thunk field N. + void + thunk_field_param(int n, char* buf, size_t buflen); + + // The function call to be executed in a separate thread (go) or + // later (defer). + Expression* call_; + // The type used for a struct to pass to a thunk, if this is not a + // simple call. + Struct_type* struct_type_; +}; + +// A go statement. + +class Go_statement : public Thunk_statement +{ + public: + Go_statement(Call_expression* call, source_location location) + : Thunk_statement(STATEMENT_GO, call, location) + { } + + protected: + tree + do_get_tree(Translate_context*); +}; + +// A defer statement. + +class Defer_statement : public Thunk_statement +{ + public: + Defer_statement(Call_expression* call, source_location location) + : Thunk_statement(STATEMENT_DEFER, call, location) + { } + + protected: + tree + do_get_tree(Translate_context*); +}; + +// A label statement. + +class Label_statement : public Statement +{ + public: + Label_statement(Label* label, source_location location) + : Statement(STATEMENT_LABEL, location), + label_(label) + { } + + // Return the label itself. + const Label* + label() const + { return this->label_; } + + protected: + int + do_traverse(Traverse*); + + tree + do_get_tree(Translate_context*); + + private: + // The label. + Label* label_; +}; + +// A for statement. + +class For_statement : public Statement +{ + public: + For_statement(Block* init, Expression* cond, Block* post, + source_location location) + : Statement(STATEMENT_FOR, location), + init_(init), cond_(cond), post_(post), statements_(NULL), + break_label_(NULL), continue_label_(NULL) + { } + + // Add the statements. + void + add_statements(Block* statements) + { + gcc_assert(this->statements_ == NULL); + this->statements_ = statements; + } + + // Return the break label for this for statement. + Unnamed_label* + break_label(); + + // Return the continue label for this for statement. + Unnamed_label* + continue_label(); + + // Set the break and continue labels for this statement. + void + set_break_continue_labels(Unnamed_label* break_label, + Unnamed_label* continue_label); + + protected: + int + do_traverse(Traverse*); + + bool + do_traverse_assignments(Traverse_assignments*) + { gcc_unreachable(); } + + Statement* + do_lower(Gogo*, Block*); + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + // The initialization statements. This may be NULL. + Block* init_; + // The condition. This may be NULL. + Expression* cond_; + // The statements to run after each iteration. This may be NULL. + Block* post_; + // The statements in the loop itself. + Block* statements_; + // The break label, if needed. + Unnamed_label* break_label_; + // The continue label, if needed. + Unnamed_label* continue_label_; +}; + +// A for statement over a range clause. + +class For_range_statement : public Statement +{ + public: + For_range_statement(Expression* index_var, Expression* value_var, + Expression* range, source_location location) + : Statement(STATEMENT_FOR_RANGE, location), + index_var_(index_var), value_var_(value_var), range_(range), + statements_(NULL), break_label_(NULL), continue_label_(NULL) + { } + + // Add the statements. + void + add_statements(Block* statements) + { + gcc_assert(this->statements_ == NULL); + this->statements_ = statements; + } + + // Return the break label for this for statement. + Unnamed_label* + break_label(); + + // Return the continue label for this for statement. + Unnamed_label* + continue_label(); + + protected: + int + do_traverse(Traverse*); + + bool + do_traverse_assignments(Traverse_assignments*) + { gcc_unreachable(); } + + Statement* + do_lower(Gogo*, Block*); + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + Expression* + make_range_ref(Named_object*, Temporary_statement*, source_location); + + Expression* + call_builtin(Gogo*, const char* funcname, Expression* arg, source_location); + + void + lower_range_array(Gogo*, Block*, Block*, Named_object*, Temporary_statement*, + Temporary_statement*, Temporary_statement*, + Block**, Expression**, Block**, Block**); + + void + lower_range_string(Gogo*, Block*, Block*, Named_object*, Temporary_statement*, + Temporary_statement*, Temporary_statement*, + Block**, Expression**, Block**, Block**); + + void + lower_range_map(Gogo*, Block*, Block*, Named_object*, Temporary_statement*, + Temporary_statement*, Temporary_statement*, + Block**, Expression**, Block**, Block**); + + void + lower_range_channel(Gogo*, Block*, Block*, Named_object*, + Temporary_statement*, Temporary_statement*, + Temporary_statement*, Block**, Expression**, Block**, + Block**); + + // The variable which is set to the index value. + Expression* index_var_; + // The variable which is set to the element value. This may be + // NULL. + Expression* value_var_; + // The expression we are ranging over. + Expression* range_; + // The statements in the block. + Block* statements_; + // The break label, if needed. + Unnamed_label* break_label_; + // The continue label, if needed. + Unnamed_label* continue_label_; +}; + +// Class Case_clauses holds the clauses of a switch statement. This +// is built by the parser. + +class Case_clauses +{ + public: + Case_clauses() + : clauses_() + { } + + // Add a new clause. CASES is a list of case expressions; it may be + // NULL. IS_DEFAULT is true if this is the default case. + // STATEMENTS is a block of statements. IS_FALLTHROUGH is true if + // after the statements the case clause should fall through to the + // next clause. + void + add(Expression_list* cases, bool is_default, Block* statements, + bool is_fallthrough, source_location location) + { + this->clauses_.push_back(Case_clause(cases, is_default, statements, + is_fallthrough, location)); + } + + // Return whether there are no clauses. + bool + empty() const + { return this->clauses_.empty(); } + + // Traverse the case clauses. + int + traverse(Traverse*); + + // Lower for a nonconstant switch. + void + lower(Block*, Temporary_statement*, Unnamed_label*) const; + + // Determine types of expressions. The Type parameter is the type + // of the switch value. + void + determine_types(Type*); + + // Check types. The Type parameter is the type of the switch value. + bool + check_types(Type*); + + // Return true if all the clauses are constant values. + bool + is_constant() const; + + // Return true if these clauses may fall through to the statements + // following the switch statement. + bool + may_fall_through() const; + + // Return the body of a SWITCH_EXPR when all the clauses are + // constants. + tree + get_constant_tree(Translate_context*, Unnamed_label* break_label) const; + + private: + // For a constant tree we need to keep a record of constants we have + // already seen. Note that INTEGER_CST trees are interned. + typedef Unordered_set(tree) Case_constants; + + // One case clause. + class Case_clause + { + public: + Case_clause() + : cases_(NULL), statements_(NULL), is_default_(false), + is_fallthrough_(false), location_(UNKNOWN_LOCATION) + { } + + Case_clause(Expression_list* cases, bool is_default, Block* statements, + bool is_fallthrough, source_location location) + : cases_(cases), statements_(statements), is_default_(is_default), + is_fallthrough_(is_fallthrough), location_(location) + { } + + // Whether this clause falls through to the next clause. + bool + is_fallthrough() const + { return this->is_fallthrough_; } + + // Whether this is the default. + bool + is_default() const + { return this->is_default_; } + + // The location of this clause. + source_location + location() const + { return this->location_; } + + // Traversal. + int + traverse(Traverse*); + + // Lower for a nonconstant switch. + void + lower(Block*, Temporary_statement*, Unnamed_label*, Unnamed_label*) const; + + // Determine types. + void + determine_types(Type*); + + // Check types. + bool + check_types(Type*); + + // Return true if all the case expressions are constant. + bool + is_constant() const; + + // Return true if this clause may fall through to execute the + // statements following the switch statement. This is not the + // same as whether this clause falls through to the next clause. + bool + may_fall_through() const; + + // Build up the body of a SWITCH_EXPR when the case expressions + // are constant. + void + get_constant_tree(Translate_context*, Unnamed_label* break_label, + Case_constants* case_constants, tree* stmt_list) const; + + private: + // The list of case expressions. + Expression_list* cases_; + // The statements to execute. + Block* statements_; + // Whether this is the default case. + bool is_default_; + // Whether this falls through after the statements. + bool is_fallthrough_; + // The location of this case clause. + source_location location_; + }; + + friend class Case_clause; + + // The type of the list of clauses. + typedef std::vector<Case_clause> Clauses; + + // All the case clauses. + Clauses clauses_; +}; + +// A switch statement. + +class Switch_statement : public Statement +{ + public: + Switch_statement(Expression* val, source_location location) + : Statement(STATEMENT_SWITCH, location), + val_(val), clauses_(NULL), break_label_(NULL) + { } + + // Add the clauses. + void + add_clauses(Case_clauses* clauses) + { + gcc_assert(this->clauses_ == NULL); + this->clauses_ = clauses; + } + + // Return the break label for this switch statement. + Unnamed_label* + break_label(); + + protected: + int + do_traverse(Traverse*); + + Statement* + do_lower(Gogo*, Block*); + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + // The value to switch on. This may be NULL. + Expression* val_; + // The case clauses. + Case_clauses* clauses_; + // The break label, if needed. + Unnamed_label* break_label_; +}; + +// Class Type_case_clauses holds the clauses of a type switch +// statement. This is built by the parser. + +class Type_case_clauses +{ + public: + Type_case_clauses() + : clauses_() + { } + + // Add a new clause. TYPE is the type for this clause; it may be + // NULL. IS_FALLTHROUGH is true if this falls through to the next + // clause; in this case STATEMENTS will be NULL. IS_DEFAULT is true + // if this is the default case. STATEMENTS is a block of + // statements; it may be NULL. + void + add(Type* type, bool is_fallthrough, bool is_default, Block* statements, + source_location location) + { + this->clauses_.push_back(Type_case_clause(type, is_fallthrough, is_default, + statements, location)); + } + + // Return whether there are no clauses. + bool + empty() const + { return this->clauses_.empty(); } + + // Traverse the type case clauses. + int + traverse(Traverse*); + + // Check for duplicates. + void + check_duplicates() const; + + // Lower to if and goto statements. + void + lower(Block*, Temporary_statement* descriptor_temp, + Unnamed_label* break_label) const; + + private: + // One type case clause. + class Type_case_clause + { + public: + Type_case_clause() + : type_(NULL), statements_(NULL), is_default_(false), + location_(UNKNOWN_LOCATION) + { } + + Type_case_clause(Type* type, bool is_fallthrough, bool is_default, + Block* statements, source_location location) + : type_(type), statements_(statements), is_fallthrough_(is_fallthrough), + is_default_(is_default), location_(location) + { } + + // The type. + Type* + type() const + { return this->type_; } + + // Whether this is the default. + bool + is_default() const + { return this->is_default_; } + + // The location of this type clause. + source_location + location() const + { return this->location_; } + + // Traversal. + int + traverse(Traverse*); + + // Lower to if and goto statements. + void + lower(Block*, Temporary_statement* descriptor_temp, + Unnamed_label* break_label, Unnamed_label** stmts_label) const; + + private: + // The type for this type clause. + Type* type_; + // The statements to execute. + Block* statements_; + // Whether this falls through--this is true for "case T1, T2". + bool is_fallthrough_; + // Whether this is the default case. + bool is_default_; + // The location of this type case clause. + source_location location_; + }; + + friend class Type_case_clause; + + // The type of the list of type clauses. + typedef std::vector<Type_case_clause> Type_clauses; + + // All the type case clauses. + Type_clauses clauses_; +}; + +// A type switch statement. + +class Type_switch_statement : public Statement +{ + public: + Type_switch_statement(Named_object* var, Expression* expr, + source_location location) + : Statement(STATEMENT_TYPE_SWITCH, location), + var_(var), expr_(expr), clauses_(NULL), break_label_(NULL) + { gcc_assert(var == NULL || expr == NULL); } + + // Add the clauses. + void + add_clauses(Type_case_clauses* clauses) + { + gcc_assert(this->clauses_ == NULL); + this->clauses_ = clauses; + } + + // Return the break label for this type switch statement. + Unnamed_label* + break_label(); + + protected: + int + do_traverse(Traverse*); + + Statement* + do_lower(Gogo*, Block*); + + tree + do_get_tree(Translate_context*) + { gcc_unreachable(); } + + private: + // Get the type descriptor. + tree + get_type_descriptor(Translate_context*, Type*, tree); + + // The variable holding the value we are switching on. + Named_object* var_; + // The expression we are switching on if there is no variable. + Expression* expr_; + // The type case clauses. + Type_case_clauses* clauses_; + // The break label, if needed. + Unnamed_label* break_label_; +}; + +#endif // !defined(GO_STATEMENTS_H) diff --git a/gcc/go/gofrontend/types.cc b/gcc/go/gofrontend/types.cc new file mode 100644 index 000000000..0db599441 --- /dev/null +++ b/gcc/go/gofrontend/types.cc @@ -0,0 +1,8644 @@ +// types.cc -- Go frontend types. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include <gmp.h> + +#ifndef ENABLE_BUILD_WITH_CXX +extern "C" +{ +#endif + +#include "toplev.h" +#include "intl.h" +#include "tree.h" +#include "gimple.h" +#include "real.h" +#include "convert.h" + +#ifndef ENABLE_BUILD_WITH_CXX +} +#endif + +#include "go-c.h" +#include "gogo.h" +#include "operator.h" +#include "expressions.h" +#include "statements.h" +#include "export.h" +#include "import.h" +#include "types.h" + +// Class Type. + +Type::Type(Type_classification classification) + : classification_(classification), tree_(NULL_TREE), + type_descriptor_decl_(NULL_TREE) +{ +} + +Type::~Type() +{ +} + +// Get the base type for a type--skip names and forward declarations. + +Type* +Type::base() +{ + switch (this->classification_) + { + case TYPE_NAMED: + return this->named_type()->named_base(); + case TYPE_FORWARD: + return this->forward_declaration_type()->real_type()->base(); + default: + return this; + } +} + +const Type* +Type::base() const +{ + switch (this->classification_) + { + case TYPE_NAMED: + return this->named_type()->named_base(); + case TYPE_FORWARD: + return this->forward_declaration_type()->real_type()->base(); + default: + return this; + } +} + +// Skip defined forward declarations. + +Type* +Type::forwarded() +{ + Type* t = this; + Forward_declaration_type* ftype = t->forward_declaration_type(); + while (ftype != NULL && ftype->is_defined()) + { + t = ftype->real_type(); + ftype = t->forward_declaration_type(); + } + return t; +} + +const Type* +Type::forwarded() const +{ + const Type* t = this; + const Forward_declaration_type* ftype = t->forward_declaration_type(); + while (ftype != NULL && ftype->is_defined()) + { + t = ftype->real_type(); + ftype = t->forward_declaration_type(); + } + return t; +} + +// If this is a named type, return it. Otherwise, return NULL. + +Named_type* +Type::named_type() +{ + return this->forwarded()->convert_no_base<Named_type, TYPE_NAMED>(); +} + +const Named_type* +Type::named_type() const +{ + return this->forwarded()->convert_no_base<const Named_type, TYPE_NAMED>(); +} + +// Return true if this type is not defined. + +bool +Type::is_undefined() const +{ + return this->forwarded()->forward_declaration_type() != NULL; +} + +// Return true if this is a basic type: a type which is not composed +// of other types, and is not void. + +bool +Type::is_basic_type() const +{ + switch (this->classification_) + { + case TYPE_INTEGER: + case TYPE_FLOAT: + case TYPE_COMPLEX: + case TYPE_BOOLEAN: + case TYPE_STRING: + case TYPE_NIL: + return true; + + case TYPE_ERROR: + case TYPE_VOID: + case TYPE_FUNCTION: + case TYPE_POINTER: + case TYPE_STRUCT: + case TYPE_ARRAY: + case TYPE_MAP: + case TYPE_CHANNEL: + case TYPE_INTERFACE: + return false; + + case TYPE_NAMED: + case TYPE_FORWARD: + return this->base()->is_basic_type(); + + default: + gcc_unreachable(); + } +} + +// Return true if this is an abstract type. + +bool +Type::is_abstract() const +{ + switch (this->classification()) + { + case TYPE_INTEGER: + return this->integer_type()->is_abstract(); + case TYPE_FLOAT: + return this->float_type()->is_abstract(); + case TYPE_COMPLEX: + return this->complex_type()->is_abstract(); + case TYPE_STRING: + return this->is_abstract_string_type(); + case TYPE_BOOLEAN: + return this->is_abstract_boolean_type(); + default: + return false; + } +} + +// Return a non-abstract version of an abstract type. + +Type* +Type::make_non_abstract_type() +{ + gcc_assert(this->is_abstract()); + switch (this->classification()) + { + case TYPE_INTEGER: + return Type::lookup_integer_type("int"); + case TYPE_FLOAT: + return Type::lookup_float_type("float64"); + case TYPE_COMPLEX: + return Type::lookup_complex_type("complex128"); + case TYPE_STRING: + return Type::lookup_string_type(); + case TYPE_BOOLEAN: + return Type::lookup_bool_type(); + default: + gcc_unreachable(); + } +} + +// Return true if this is an error type. Don't give an error if we +// try to dereference an undefined forwarding type, as this is called +// in the parser when the type may legitimately be undefined. + +bool +Type::is_error_type() const +{ + const Type* t = this->forwarded(); + // Note that we return false for an undefined forward type. + switch (t->classification_) + { + case TYPE_ERROR: + return true; + case TYPE_NAMED: + return t->named_type()->is_named_error_type(); + default: + return false; + } +} + +// If this is a pointer type, return the type to which it points. +// Otherwise, return NULL. + +Type* +Type::points_to() const +{ + const Pointer_type* ptype = this->convert<const Pointer_type, + TYPE_POINTER>(); + return ptype == NULL ? NULL : ptype->points_to(); +} + +// Return whether this is an open array type. + +bool +Type::is_open_array_type() const +{ + return this->array_type() != NULL && this->array_type()->length() == NULL; +} + +// Return whether this is the predeclared constant nil being used as a +// type. + +bool +Type::is_nil_constant_as_type() const +{ + const Type* t = this->forwarded(); + if (t->forward_declaration_type() != NULL) + { + const Named_object* no = t->forward_declaration_type()->named_object(); + if (no->is_unknown()) + no = no->unknown_value()->real_named_object(); + if (no != NULL + && no->is_const() + && no->const_value()->expr()->is_nil_expression()) + return true; + } + return false; +} + +// Traverse a type. + +int +Type::traverse(Type* type, Traverse* traverse) +{ + gcc_assert((traverse->traverse_mask() & Traverse::traverse_types) != 0 + || (traverse->traverse_mask() + & Traverse::traverse_expressions) != 0); + if (traverse->remember_type(type)) + { + // We have already traversed this type. + return TRAVERSE_CONTINUE; + } + if ((traverse->traverse_mask() & Traverse::traverse_types) != 0) + { + int t = traverse->type(type); + if (t == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + else if (t == TRAVERSE_SKIP_COMPONENTS) + return TRAVERSE_CONTINUE; + } + // An array type has an expression which we need to traverse if + // traverse_expressions is set. + if (type->do_traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Default implementation for do_traverse for child class. + +int +Type::do_traverse(Traverse*) +{ + return TRAVERSE_CONTINUE; +} + +// Return whether two types are identical. If ERRORS_ARE_IDENTICAL, +// then return true for all erroneous types; this is used to avoid +// cascading errors. If REASON is not NULL, optionally set *REASON to +// the reason the types are not identical. + +bool +Type::are_identical(const Type* t1, const Type* t2, bool errors_are_identical, + std::string* reason) +{ + if (t1 == NULL || t2 == NULL) + { + // Something is wrong. + return errors_are_identical ? true : t1 == t2; + } + + // Skip defined forward declarations. + t1 = t1->forwarded(); + t2 = t2->forwarded(); + + if (t1 == t2) + return true; + + // An undefined forward declaration is an error. + if (t1->forward_declaration_type() != NULL + || t2->forward_declaration_type() != NULL) + return errors_are_identical; + + // Avoid cascading errors with error types. + if (t1->is_error_type() || t2->is_error_type()) + { + if (errors_are_identical) + return true; + return t1->is_error_type() && t2->is_error_type(); + } + + // Get a good reason for the sink type. Note that the sink type on + // the left hand side of an assignment is handled in are_assignable. + if (t1->is_sink_type() || t2->is_sink_type()) + { + if (reason != NULL) + *reason = "invalid use of _"; + return false; + } + + // A named type is only identical to itself. + if (t1->named_type() != NULL || t2->named_type() != NULL) + return false; + + // Check type shapes. + if (t1->classification() != t2->classification()) + return false; + + switch (t1->classification()) + { + case TYPE_VOID: + case TYPE_BOOLEAN: + case TYPE_STRING: + case TYPE_NIL: + // These types are always identical. + return true; + + case TYPE_INTEGER: + return t1->integer_type()->is_identical(t2->integer_type()); + + case TYPE_FLOAT: + return t1->float_type()->is_identical(t2->float_type()); + + case TYPE_COMPLEX: + return t1->complex_type()->is_identical(t2->complex_type()); + + case TYPE_FUNCTION: + return t1->function_type()->is_identical(t2->function_type(), + false, + errors_are_identical, + reason); + + case TYPE_POINTER: + return Type::are_identical(t1->points_to(), t2->points_to(), + errors_are_identical, reason); + + case TYPE_STRUCT: + return t1->struct_type()->is_identical(t2->struct_type(), + errors_are_identical); + + case TYPE_ARRAY: + return t1->array_type()->is_identical(t2->array_type(), + errors_are_identical); + + case TYPE_MAP: + return t1->map_type()->is_identical(t2->map_type(), + errors_are_identical); + + case TYPE_CHANNEL: + return t1->channel_type()->is_identical(t2->channel_type(), + errors_are_identical); + + case TYPE_INTERFACE: + return t1->interface_type()->is_identical(t2->interface_type(), + errors_are_identical); + + case TYPE_CALL_MULTIPLE_RESULT: + if (reason != NULL) + *reason = "invalid use of multiple value function call"; + return false; + + default: + gcc_unreachable(); + } +} + +// Return true if it's OK to have a binary operation with types LHS +// and RHS. This is not used for shifts or comparisons. + +bool +Type::are_compatible_for_binop(const Type* lhs, const Type* rhs) +{ + if (Type::are_identical(lhs, rhs, true, NULL)) + return true; + + // A constant of abstract bool type may be mixed with any bool type. + if ((rhs->is_abstract_boolean_type() && lhs->is_boolean_type()) + || (lhs->is_abstract_boolean_type() && rhs->is_boolean_type())) + return true; + + // A constant of abstract string type may be mixed with any string + // type. + if ((rhs->is_abstract_string_type() && lhs->is_string_type()) + || (lhs->is_abstract_string_type() && rhs->is_string_type())) + return true; + + lhs = lhs->base(); + rhs = rhs->base(); + + // A constant of abstract integer, float, or complex type may be + // mixed with an integer, float, or complex type. + if ((rhs->is_abstract() + && (rhs->integer_type() != NULL + || rhs->float_type() != NULL + || rhs->complex_type() != NULL) + && (lhs->integer_type() != NULL + || lhs->float_type() != NULL + || lhs->complex_type() != NULL)) + || (lhs->is_abstract() + && (lhs->integer_type() != NULL + || lhs->float_type() != NULL + || lhs->complex_type() != NULL) + && (rhs->integer_type() != NULL + || rhs->float_type() != NULL + || rhs->complex_type() != NULL))) + return true; + + // The nil type may be compared to a pointer, an interface type, a + // slice type, a channel type, a map type, or a function type. + if (lhs->is_nil_type() + && (rhs->points_to() != NULL + || rhs->interface_type() != NULL + || rhs->is_open_array_type() + || rhs->map_type() != NULL + || rhs->channel_type() != NULL + || rhs->function_type() != NULL)) + return true; + if (rhs->is_nil_type() + && (lhs->points_to() != NULL + || lhs->interface_type() != NULL + || lhs->is_open_array_type() + || lhs->map_type() != NULL + || lhs->channel_type() != NULL + || lhs->function_type() != NULL)) + return true; + + return false; +} + +// Return true if a value with type RHS may be assigned to a variable +// with type LHS. If REASON is not NULL, set *REASON to the reason +// the types are not assignable. + +bool +Type::are_assignable(const Type* lhs, const Type* rhs, std::string* reason) +{ + // Do some checks first. Make sure the types are defined. + if (rhs != NULL + && rhs->forwarded()->forward_declaration_type() == NULL + && rhs->is_void_type()) + { + if (reason != NULL) + *reason = "non-value used as value"; + return false; + } + + if (lhs != NULL && lhs->forwarded()->forward_declaration_type() == NULL) + { + // Any value may be assigned to the blank identifier. + if (lhs->is_sink_type()) + return true; + + // All fields of a struct must be exported, or the assignment + // must be in the same package. + if (rhs != NULL && rhs->forwarded()->forward_declaration_type() == NULL) + { + if (lhs->has_hidden_fields(NULL, reason) + || rhs->has_hidden_fields(NULL, reason)) + return false; + } + } + + // Identical types are assignable. + if (Type::are_identical(lhs, rhs, true, reason)) + return true; + + // The types are assignable if they have identical underlying types + // and either LHS or RHS is not a named type. + if (((lhs->named_type() != NULL && rhs->named_type() == NULL) + || (rhs->named_type() != NULL && lhs->named_type() == NULL)) + && Type::are_identical(lhs->base(), rhs->base(), true, reason)) + return true; + + // The types are assignable if LHS is an interface type and RHS + // implements the required methods. + const Interface_type* lhs_interface_type = lhs->interface_type(); + if (lhs_interface_type != NULL) + { + if (lhs_interface_type->implements_interface(rhs, reason)) + return true; + const Interface_type* rhs_interface_type = rhs->interface_type(); + if (rhs_interface_type != NULL + && lhs_interface_type->is_compatible_for_assign(rhs_interface_type, + reason)) + return true; + } + + // The type are assignable if RHS is a bidirectional channel type, + // LHS is a channel type, they have identical element types, and + // either LHS or RHS is not a named type. + if (lhs->channel_type() != NULL + && rhs->channel_type() != NULL + && rhs->channel_type()->may_send() + && rhs->channel_type()->may_receive() + && (lhs->named_type() == NULL || rhs->named_type() == NULL) + && Type::are_identical(lhs->channel_type()->element_type(), + rhs->channel_type()->element_type(), + true, + reason)) + return true; + + // The nil type may be assigned to a pointer, function, slice, map, + // channel, or interface type. + if (rhs->is_nil_type() + && (lhs->points_to() != NULL + || lhs->function_type() != NULL + || lhs->is_open_array_type() + || lhs->map_type() != NULL + || lhs->channel_type() != NULL + || lhs->interface_type() != NULL)) + return true; + + // An untyped numeric constant may be assigned to a numeric type if + // it is representable in that type. + if ((rhs->is_abstract() + && (rhs->integer_type() != NULL + || rhs->float_type() != NULL + || rhs->complex_type() != NULL)) + && (lhs->integer_type() != NULL + || lhs->float_type() != NULL + || lhs->complex_type() != NULL)) + return true; + + // Give some better error messages. + if (reason != NULL && reason->empty()) + { + if (rhs->interface_type() != NULL) + reason->assign(_("need explicit conversion")); + else if (rhs->is_call_multiple_result_type()) + reason->assign(_("multiple value function call in " + "single value context")); + else if (lhs->named_type() != NULL && rhs->named_type() != NULL) + { + size_t len = (lhs->named_type()->name().length() + + rhs->named_type()->name().length() + + 100); + char* buf = new char[len]; + snprintf(buf, len, _("cannot use type %s as type %s"), + rhs->named_type()->message_name().c_str(), + lhs->named_type()->message_name().c_str()); + reason->assign(buf); + delete[] buf; + } + } + + return false; +} + +// Return true if a value with type RHS may be converted to type LHS. +// If REASON is not NULL, set *REASON to the reason the types are not +// convertible. + +bool +Type::are_convertible(const Type* lhs, const Type* rhs, std::string* reason) +{ + // The types are convertible if they are assignable. + if (Type::are_assignable(lhs, rhs, reason)) + return true; + + // The types are convertible if they have identical underlying + // types. + if ((lhs->named_type() != NULL || rhs->named_type() != NULL) + && Type::are_identical(lhs->base(), rhs->base(), true, reason)) + return true; + + // The types are convertible if they are both unnamed pointer types + // and their pointer base types have identical underlying types. + if (lhs->named_type() == NULL + && rhs->named_type() == NULL + && lhs->points_to() != NULL + && rhs->points_to() != NULL + && (lhs->points_to()->named_type() != NULL + || rhs->points_to()->named_type() != NULL) + && Type::are_identical(lhs->points_to()->base(), + rhs->points_to()->base(), + true, + reason)) + return true; + + // Integer and floating point types are convertible to each other. + if ((lhs->integer_type() != NULL || lhs->float_type() != NULL) + && (rhs->integer_type() != NULL || rhs->float_type() != NULL)) + return true; + + // Complex types are convertible to each other. + if (lhs->complex_type() != NULL && rhs->complex_type() != NULL) + return true; + + // An integer, or []byte, or []int, may be converted to a string. + if (lhs->is_string_type()) + { + if (rhs->integer_type() != NULL) + return true; + if (rhs->is_open_array_type() && rhs->named_type() == NULL) + { + const Type* e = rhs->array_type()->element_type()->forwarded(); + if (e->integer_type() != NULL + && (e == Type::lookup_integer_type("uint8") + || e == Type::lookup_integer_type("int"))) + return true; + } + } + + // A string may be converted to []byte or []int. + if (rhs->is_string_type() + && lhs->is_open_array_type() + && lhs->named_type() == NULL) + { + const Type* e = lhs->array_type()->element_type()->forwarded(); + if (e->integer_type() != NULL + && (e == Type::lookup_integer_type("uint8") + || e == Type::lookup_integer_type("int"))) + return true; + } + + // An unsafe.Pointer type may be converted to any pointer type or to + // uintptr, and vice-versa. + if (lhs->is_unsafe_pointer_type() + && (rhs->points_to() != NULL + || (rhs->integer_type() != NULL + && rhs->forwarded() == Type::lookup_integer_type("uintptr")))) + return true; + if (rhs->is_unsafe_pointer_type() + && (lhs->points_to() != NULL + || (lhs->integer_type() != NULL + && lhs->forwarded() == Type::lookup_integer_type("uintptr")))) + return true; + + // Give a better error message. + if (reason != NULL) + { + if (reason->empty()) + *reason = "invalid type conversion"; + else + { + std::string s = "invalid type conversion ("; + s += *reason; + s += ')'; + *reason = s; + } + } + + return false; +} + +// Return whether this type has any hidden fields. This is only a +// possibility for a few types. + +bool +Type::has_hidden_fields(const Named_type* within, std::string* reason) const +{ + switch (this->forwarded()->classification_) + { + case TYPE_NAMED: + return this->named_type()->named_type_has_hidden_fields(reason); + case TYPE_STRUCT: + return this->struct_type()->struct_has_hidden_fields(within, reason); + case TYPE_ARRAY: + return this->array_type()->array_has_hidden_fields(within, reason); + default: + return false; + } +} + +// Return a hash code for the type to be used for method lookup. + +unsigned int +Type::hash_for_method(Gogo* gogo) const +{ + unsigned int ret = 0; + if (this->classification_ != TYPE_FORWARD) + ret += this->classification_; + return ret + this->do_hash_for_method(gogo); +} + +// Default implementation of do_hash_for_method. This is appropriate +// for types with no subfields. + +unsigned int +Type::do_hash_for_method(Gogo*) const +{ + return 0; +} + +// Return a hash code for a string, given a starting hash. + +unsigned int +Type::hash_string(const std::string& s, unsigned int h) +{ + const char* p = s.data(); + size_t len = s.length(); + for (; len > 0; --len) + { + h ^= *p++; + h*= 16777619; + } + return h; +} + +// Default check for the expression passed to make. Any type which +// may be used with make implements its own version of this. + +bool +Type::do_check_make_expression(Expression_list*, source_location) +{ + gcc_unreachable(); +} + +// Return whether an expression has an integer value. Report an error +// if not. This is used when handling calls to the predeclared make +// function. + +bool +Type::check_int_value(Expression* e, const char* errmsg, + source_location location) +{ + if (e->type()->integer_type() != NULL) + return true; + + // Check for a floating point constant with integer value. + mpfr_t fval; + mpfr_init(fval); + + Type* dummy; + if (e->float_constant_value(fval, &dummy) && mpfr_integer_p(fval)) + { + mpz_t ival; + mpz_init(ival); + + bool ok = false; + + mpfr_clear_overflow(); + mpfr_clear_erangeflag(); + mpfr_get_z(ival, fval, GMP_RNDN); + if (!mpfr_overflow_p() + && !mpfr_erangeflag_p() + && mpz_sgn(ival) >= 0) + { + Named_type* ntype = Type::lookup_integer_type("int"); + Integer_type* inttype = ntype->integer_type(); + mpz_t max; + mpz_init_set_ui(max, 1); + mpz_mul_2exp(max, max, inttype->bits() - 1); + ok = mpz_cmp(ival, max) < 0; + mpz_clear(max); + } + mpz_clear(ival); + + if (ok) + { + mpfr_clear(fval); + return true; + } + } + + mpfr_clear(fval); + + error_at(location, "%s", errmsg); + return false; +} + +// A hash table mapping unnamed types to trees. + +Type::Type_trees Type::type_trees; + +// Return a tree representing this type. + +tree +Type::get_tree(Gogo* gogo) +{ + if (this->tree_ != NULL) + return this->tree_; + + if (this->forward_declaration_type() != NULL + || this->named_type() != NULL) + return this->get_tree_without_hash(gogo); + + if (this->is_error_type()) + return error_mark_node; + + // To avoid confusing GIMPLE, we need to translate all identical Go + // types to the same GIMPLE type. We use a hash table to do that. + // There is no need to use the hash table for named types, as named + // types are only identical to themselves. + + std::pair<Type*, tree> val(this, NULL); + std::pair<Type_trees::iterator, bool> ins = + Type::type_trees.insert(val); + if (!ins.second && ins.first->second != NULL_TREE) + { + if (gogo != NULL && gogo->named_types_are_converted()) + this->tree_ = ins.first->second; + return ins.first->second; + } + + tree t = this->get_tree_without_hash(gogo); + + if (ins.first->second == NULL_TREE) + ins.first->second = t; + else + { + // We have already created a tree for this type. This can + // happen when an unnamed type is defined using a named type + // which in turns uses an identical unnamed type. Use the tree + // we created earlier and ignore the one we just built. + t = ins.first->second; + if (gogo == NULL || !gogo->named_types_are_converted()) + return t; + this->tree_ = t; + } + + return t; +} + +// Return a tree for a type without looking in the hash table for +// identical types. This is used for named types, since there is no +// point to looking in the hash table for them. + +tree +Type::get_tree_without_hash(Gogo* gogo) +{ + if (this->tree_ == NULL_TREE) + { + tree t = this->do_get_tree(gogo); + + // For a recursive function or pointer type, we will temporarily + // return ptr_type_node during the recursion. We don't want to + // record that for a forwarding type, as it may confuse us + // later. + if (t == ptr_type_node && this->forward_declaration_type() != NULL) + return t; + + if (gogo == NULL || !gogo->named_types_are_converted()) + return t; + + this->tree_ = t; + go_preserve_from_gc(t); + } + + return this->tree_; +} + +// Return a tree representing a zero initialization for this type. + +tree +Type::get_init_tree(Gogo* gogo, bool is_clear) +{ + tree type_tree = this->get_tree(gogo); + if (type_tree == error_mark_node) + return error_mark_node; + return this->do_get_init_tree(gogo, type_tree, is_clear); +} + +// Any type which supports the builtin make function must implement +// this. + +tree +Type::do_make_expression_tree(Translate_context*, Expression_list*, + source_location) +{ + gcc_unreachable(); +} + +// Return a pointer to the type descriptor for this type. + +tree +Type::type_descriptor_pointer(Gogo* gogo) +{ + Type* t = this->forwarded(); + if (t->type_descriptor_decl_ == NULL_TREE) + { + Expression* e = t->do_type_descriptor(gogo, NULL); + gogo->build_type_descriptor_decl(t, e, &t->type_descriptor_decl_); + gcc_assert(t->type_descriptor_decl_ != NULL_TREE + && (t->type_descriptor_decl_ == error_mark_node + || DECL_P(t->type_descriptor_decl_))); + } + if (t->type_descriptor_decl_ == error_mark_node) + return error_mark_node; + return build_fold_addr_expr(t->type_descriptor_decl_); +} + +// Return a composite literal for a type descriptor. + +Expression* +Type::type_descriptor(Gogo* gogo, Type* type) +{ + return type->do_type_descriptor(gogo, NULL); +} + +// Return a composite literal for a type descriptor with a name. + +Expression* +Type::named_type_descriptor(Gogo* gogo, Type* type, Named_type* name) +{ + gcc_assert(name != NULL && type->named_type() != name); + return type->do_type_descriptor(gogo, name); +} + +// Make a builtin struct type from a list of fields. The fields are +// pairs of a name and a type. + +Struct_type* +Type::make_builtin_struct_type(int nfields, ...) +{ + va_list ap; + va_start(ap, nfields); + + source_location bloc = BUILTINS_LOCATION; + Struct_field_list* sfl = new Struct_field_list(); + for (int i = 0; i < nfields; i++) + { + const char* field_name = va_arg(ap, const char *); + Type* type = va_arg(ap, Type*); + sfl->push_back(Struct_field(Typed_identifier(field_name, type, bloc))); + } + + va_end(ap); + + return Type::make_struct_type(sfl, bloc); +} + +// A list of builtin named types. + +std::vector<Named_type*> Type::named_builtin_types; + +// Make a builtin named type. + +Named_type* +Type::make_builtin_named_type(const char* name, Type* type) +{ + source_location bloc = BUILTINS_LOCATION; + Named_object* no = Named_object::make_type(name, NULL, type, bloc); + Named_type* ret = no->type_value(); + Type::named_builtin_types.push_back(ret); + return ret; +} + +// Convert the named builtin types. + +void +Type::convert_builtin_named_types(Gogo* gogo) +{ + for (std::vector<Named_type*>::const_iterator p = + Type::named_builtin_types.begin(); + p != Type::named_builtin_types.end(); + ++p) + { + bool r = (*p)->verify(); + gcc_assert(r); + (*p)->convert(gogo); + } +} + +// Return the type of a type descriptor. We should really tie this to +// runtime.Type rather than copying it. This must match commonType in +// libgo/go/runtime/type.go. + +Type* +Type::make_type_descriptor_type() +{ + static Type* ret; + if (ret == NULL) + { + source_location bloc = BUILTINS_LOCATION; + + Type* uint8_type = Type::lookup_integer_type("uint8"); + Type* uint32_type = Type::lookup_integer_type("uint32"); + Type* uintptr_type = Type::lookup_integer_type("uintptr"); + Type* string_type = Type::lookup_string_type(); + Type* pointer_string_type = Type::make_pointer_type(string_type); + + // This is an unnamed version of unsafe.Pointer. Perhaps we + // should use the named version instead, although that would + // require us to create the unsafe package if it has not been + // imported. It probably doesn't matter. + Type* void_type = Type::make_void_type(); + Type* unsafe_pointer_type = Type::make_pointer_type(void_type); + + // Forward declaration for the type descriptor type. + Named_object* named_type_descriptor_type = + Named_object::make_type_declaration("commonType", NULL, bloc); + Type* ft = Type::make_forward_declaration(named_type_descriptor_type); + Type* pointer_type_descriptor_type = Type::make_pointer_type(ft); + + // The type of a method on a concrete type. + Struct_type* method_type = + Type::make_builtin_struct_type(5, + "name", pointer_string_type, + "pkgPath", pointer_string_type, + "mtyp", pointer_type_descriptor_type, + "typ", pointer_type_descriptor_type, + "tfn", unsafe_pointer_type); + Named_type* named_method_type = + Type::make_builtin_named_type("method", method_type); + + // Information for types with a name or methods. + Type* slice_named_method_type = + Type::make_array_type(named_method_type, NULL); + Struct_type* uncommon_type = + Type::make_builtin_struct_type(3, + "name", pointer_string_type, + "pkgPath", pointer_string_type, + "methods", slice_named_method_type); + Named_type* named_uncommon_type = + Type::make_builtin_named_type("uncommonType", uncommon_type); + + Type* pointer_uncommon_type = + Type::make_pointer_type(named_uncommon_type); + + // The type descriptor type. + + Typed_identifier_list* params = new Typed_identifier_list(); + params->push_back(Typed_identifier("", unsafe_pointer_type, bloc)); + params->push_back(Typed_identifier("", uintptr_type, bloc)); + + Typed_identifier_list* results = new Typed_identifier_list(); + results->push_back(Typed_identifier("", uintptr_type, bloc)); + + Type* hashfn_type = Type::make_function_type(NULL, params, results, bloc); + + params = new Typed_identifier_list(); + params->push_back(Typed_identifier("", unsafe_pointer_type, bloc)); + params->push_back(Typed_identifier("", unsafe_pointer_type, bloc)); + params->push_back(Typed_identifier("", uintptr_type, bloc)); + + results = new Typed_identifier_list(); + results->push_back(Typed_identifier("", Type::lookup_bool_type(), bloc)); + + Type* equalfn_type = Type::make_function_type(NULL, params, results, + bloc); + + Struct_type* type_descriptor_type = + Type::make_builtin_struct_type(9, + "Kind", uint8_type, + "align", uint8_type, + "fieldAlign", uint8_type, + "size", uintptr_type, + "hash", uint32_type, + "hashfn", hashfn_type, + "equalfn", equalfn_type, + "string", pointer_string_type, + "", pointer_uncommon_type); + + Named_type* named = Type::make_builtin_named_type("commonType", + type_descriptor_type); + + named_type_descriptor_type->set_type_value(named); + + ret = named; + } + + return ret; +} + +// Make the type of a pointer to a type descriptor as represented in +// Go. + +Type* +Type::make_type_descriptor_ptr_type() +{ + static Type* ret; + if (ret == NULL) + ret = Type::make_pointer_type(Type::make_type_descriptor_type()); + return ret; +} + +// Return the names of runtime functions which compute a hash code for +// this type and which compare whether two values of this type are +// equal. + +void +Type::type_functions(const char** hash_fn, const char** equal_fn) const +{ + switch (this->base()->classification()) + { + case Type::TYPE_ERROR: + case Type::TYPE_VOID: + case Type::TYPE_NIL: + // These types can not be hashed or compared. + *hash_fn = "__go_type_hash_error"; + *equal_fn = "__go_type_equal_error"; + break; + + case Type::TYPE_BOOLEAN: + case Type::TYPE_INTEGER: + case Type::TYPE_FLOAT: + case Type::TYPE_COMPLEX: + case Type::TYPE_POINTER: + case Type::TYPE_FUNCTION: + case Type::TYPE_MAP: + case Type::TYPE_CHANNEL: + *hash_fn = "__go_type_hash_identity"; + *equal_fn = "__go_type_equal_identity"; + break; + + case Type::TYPE_STRING: + *hash_fn = "__go_type_hash_string"; + *equal_fn = "__go_type_equal_string"; + break; + + case Type::TYPE_STRUCT: + case Type::TYPE_ARRAY: + // These types can not be hashed or compared. + *hash_fn = "__go_type_hash_error"; + *equal_fn = "__go_type_equal_error"; + break; + + case Type::TYPE_INTERFACE: + if (this->interface_type()->is_empty()) + { + *hash_fn = "__go_type_hash_empty_interface"; + *equal_fn = "__go_type_equal_empty_interface"; + } + else + { + *hash_fn = "__go_type_hash_interface"; + *equal_fn = "__go_type_equal_interface"; + } + break; + + case Type::TYPE_NAMED: + case Type::TYPE_FORWARD: + gcc_unreachable(); + + default: + gcc_unreachable(); + } +} + +// Return a composite literal for the type descriptor for a plain type +// of kind RUNTIME_TYPE_KIND named NAME. + +Expression* +Type::type_descriptor_constructor(Gogo* gogo, int runtime_type_kind, + Named_type* name, const Methods* methods, + bool only_value_methods) +{ + source_location bloc = BUILTINS_LOCATION; + + Type* td_type = Type::make_type_descriptor_type(); + const Struct_field_list* fields = td_type->struct_type()->fields(); + + Expression_list* vals = new Expression_list(); + vals->reserve(9); + + Struct_field_list::const_iterator p = fields->begin(); + gcc_assert(p->field_name() == "Kind"); + mpz_t iv; + mpz_init_set_ui(iv, runtime_type_kind); + vals->push_back(Expression::make_integer(&iv, p->type(), bloc)); + + ++p; + gcc_assert(p->field_name() == "align"); + Expression::Type_info type_info = Expression::TYPE_INFO_ALIGNMENT; + vals->push_back(Expression::make_type_info(this, type_info)); + + ++p; + gcc_assert(p->field_name() == "fieldAlign"); + type_info = Expression::TYPE_INFO_FIELD_ALIGNMENT; + vals->push_back(Expression::make_type_info(this, type_info)); + + ++p; + gcc_assert(p->field_name() == "size"); + type_info = Expression::TYPE_INFO_SIZE; + vals->push_back(Expression::make_type_info(this, type_info)); + + ++p; + gcc_assert(p->field_name() == "hash"); + mpz_set_ui(iv, this->hash_for_method(gogo)); + vals->push_back(Expression::make_integer(&iv, p->type(), bloc)); + + const char* hash_fn; + const char* equal_fn; + this->type_functions(&hash_fn, &equal_fn); + + ++p; + gcc_assert(p->field_name() == "hashfn"); + Function_type* fntype = p->type()->function_type(); + Named_object* no = Named_object::make_function_declaration(hash_fn, NULL, + fntype, + bloc); + no->func_declaration_value()->set_asm_name(hash_fn); + vals->push_back(Expression::make_func_reference(no, NULL, bloc)); + + ++p; + gcc_assert(p->field_name() == "equalfn"); + fntype = p->type()->function_type(); + no = Named_object::make_function_declaration(equal_fn, NULL, fntype, bloc); + no->func_declaration_value()->set_asm_name(equal_fn); + vals->push_back(Expression::make_func_reference(no, NULL, bloc)); + + ++p; + gcc_assert(p->field_name() == "string"); + Expression* s = Expression::make_string((name != NULL + ? name->reflection(gogo) + : this->reflection(gogo)), + bloc); + vals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc)); + + ++p; + gcc_assert(p->field_name() == "uncommonType"); + if (name == NULL && methods == NULL) + vals->push_back(Expression::make_nil(bloc)); + else + { + if (methods == NULL) + methods = name->methods(); + vals->push_back(this->uncommon_type_constructor(gogo, + p->type()->deref(), + name, methods, + only_value_methods)); + } + + ++p; + gcc_assert(p == fields->end()); + + mpz_clear(iv); + + return Expression::make_struct_composite_literal(td_type, vals, bloc); +} + +// Return a composite literal for the uncommon type information for +// this type. UNCOMMON_STRUCT_TYPE is the type of the uncommon type +// struct. If name is not NULL, it is the name of the type. If +// METHODS is not NULL, it is the list of methods. ONLY_VALUE_METHODS +// is true if only value methods should be included. At least one of +// NAME and METHODS must not be NULL. + +Expression* +Type::uncommon_type_constructor(Gogo* gogo, Type* uncommon_type, + Named_type* name, const Methods* methods, + bool only_value_methods) const +{ + source_location bloc = BUILTINS_LOCATION; + + const Struct_field_list* fields = uncommon_type->struct_type()->fields(); + + Expression_list* vals = new Expression_list(); + vals->reserve(3); + + Struct_field_list::const_iterator p = fields->begin(); + gcc_assert(p->field_name() == "name"); + + ++p; + gcc_assert(p->field_name() == "pkgPath"); + + if (name == NULL) + { + vals->push_back(Expression::make_nil(bloc)); + vals->push_back(Expression::make_nil(bloc)); + } + else + { + Named_object* no = name->named_object(); + std::string n = Gogo::unpack_hidden_name(no->name()); + Expression* s = Expression::make_string(n, bloc); + vals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc)); + + if (name->is_builtin()) + vals->push_back(Expression::make_nil(bloc)); + else + { + const Package* package = no->package(); + const std::string& unique_prefix(package == NULL + ? gogo->unique_prefix() + : package->unique_prefix()); + const std::string& package_name(package == NULL + ? gogo->package_name() + : package->name()); + n.assign(unique_prefix); + n.append(1, '.'); + n.append(package_name); + if (name->in_function() != NULL) + { + n.append(1, '.'); + n.append(Gogo::unpack_hidden_name(name->in_function()->name())); + } + s = Expression::make_string(n, bloc); + vals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc)); + } + } + + ++p; + gcc_assert(p->field_name() == "methods"); + vals->push_back(this->methods_constructor(gogo, p->type(), methods, + only_value_methods)); + + ++p; + gcc_assert(p == fields->end()); + + Expression* r = Expression::make_struct_composite_literal(uncommon_type, + vals, bloc); + return Expression::make_unary(OPERATOR_AND, r, bloc); +} + +// Sort methods by name. + +class Sort_methods +{ + public: + bool + operator()(const std::pair<std::string, const Method*>& m1, + const std::pair<std::string, const Method*>& m2) const + { return m1.first < m2.first; } +}; + +// Return a composite literal for the type method table for this type. +// METHODS_TYPE is the type of the table, and is a slice type. +// METHODS is the list of methods. If ONLY_VALUE_METHODS is true, +// then only value methods are used. + +Expression* +Type::methods_constructor(Gogo* gogo, Type* methods_type, + const Methods* methods, + bool only_value_methods) const +{ + source_location bloc = BUILTINS_LOCATION; + + std::vector<std::pair<std::string, const Method*> > smethods; + if (methods != NULL) + { + smethods.reserve(methods->count()); + for (Methods::const_iterator p = methods->begin(); + p != methods->end(); + ++p) + { + if (p->second->is_ambiguous()) + continue; + if (only_value_methods && !p->second->is_value_method()) + continue; + smethods.push_back(std::make_pair(p->first, p->second)); + } + } + + if (smethods.empty()) + return Expression::make_slice_composite_literal(methods_type, NULL, bloc); + + std::sort(smethods.begin(), smethods.end(), Sort_methods()); + + Type* method_type = methods_type->array_type()->element_type(); + + Expression_list* vals = new Expression_list(); + vals->reserve(smethods.size()); + for (std::vector<std::pair<std::string, const Method*> >::const_iterator p + = smethods.begin(); + p != smethods.end(); + ++p) + vals->push_back(this->method_constructor(gogo, method_type, p->first, + p->second)); + + return Expression::make_slice_composite_literal(methods_type, vals, bloc); +} + +// Return a composite literal for a single method. METHOD_TYPE is the +// type of the entry. METHOD_NAME is the name of the method and M is +// the method information. + +Expression* +Type::method_constructor(Gogo*, Type* method_type, + const std::string& method_name, + const Method* m) const +{ + source_location bloc = BUILTINS_LOCATION; + + const Struct_field_list* fields = method_type->struct_type()->fields(); + + Expression_list* vals = new Expression_list(); + vals->reserve(5); + + Struct_field_list::const_iterator p = fields->begin(); + gcc_assert(p->field_name() == "name"); + const std::string n = Gogo::unpack_hidden_name(method_name); + Expression* s = Expression::make_string(n, bloc); + vals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc)); + + ++p; + gcc_assert(p->field_name() == "pkgPath"); + if (!Gogo::is_hidden_name(method_name)) + vals->push_back(Expression::make_nil(bloc)); + else + { + s = Expression::make_string(Gogo::hidden_name_prefix(method_name), bloc); + vals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc)); + } + + Named_object* no = (m->needs_stub_method() + ? m->stub_object() + : m->named_object()); + + Function_type* mtype; + if (no->is_function()) + mtype = no->func_value()->type(); + else + mtype = no->func_declaration_value()->type(); + gcc_assert(mtype->is_method()); + Type* nonmethod_type = mtype->copy_without_receiver(); + + ++p; + gcc_assert(p->field_name() == "mtyp"); + vals->push_back(Expression::make_type_descriptor(nonmethod_type, bloc)); + + ++p; + gcc_assert(p->field_name() == "typ"); + vals->push_back(Expression::make_type_descriptor(mtype, bloc)); + + ++p; + gcc_assert(p->field_name() == "tfn"); + vals->push_back(Expression::make_func_reference(no, NULL, bloc)); + + ++p; + gcc_assert(p == fields->end()); + + return Expression::make_struct_composite_literal(method_type, vals, bloc); +} + +// Return a composite literal for the type descriptor of a plain type. +// RUNTIME_TYPE_KIND is the value of the kind field. If NAME is not +// NULL, it is the name to use as well as the list of methods. + +Expression* +Type::plain_type_descriptor(Gogo* gogo, int runtime_type_kind, + Named_type* name) +{ + return this->type_descriptor_constructor(gogo, runtime_type_kind, + name, NULL, true); +} + +// Return the type reflection string for this type. + +std::string +Type::reflection(Gogo* gogo) const +{ + std::string ret; + + // The do_reflection virtual function should set RET to the + // reflection string. + this->do_reflection(gogo, &ret); + + return ret; +} + +// Return a mangled name for the type. + +std::string +Type::mangled_name(Gogo* gogo) const +{ + std::string ret; + + // The do_mangled_name virtual function should set RET to the + // mangled name. For a composite type it should append a code for + // the composition and then call do_mangled_name on the components. + this->do_mangled_name(gogo, &ret); + + return ret; +} + +// Default function to export a type. + +void +Type::do_export(Export*) const +{ + gcc_unreachable(); +} + +// Import a type. + +Type* +Type::import_type(Import* imp) +{ + if (imp->match_c_string("(")) + return Function_type::do_import(imp); + else if (imp->match_c_string("*")) + return Pointer_type::do_import(imp); + else if (imp->match_c_string("struct ")) + return Struct_type::do_import(imp); + else if (imp->match_c_string("[")) + return Array_type::do_import(imp); + else if (imp->match_c_string("map ")) + return Map_type::do_import(imp); + else if (imp->match_c_string("chan ")) + return Channel_type::do_import(imp); + else if (imp->match_c_string("interface")) + return Interface_type::do_import(imp); + else + { + error_at(imp->location(), "import error: expected type"); + return Type::make_error_type(); + } +} + +// A type used to indicate a parsing error. This exists to simplify +// later error detection. + +class Error_type : public Type +{ + public: + Error_type() + : Type(TYPE_ERROR) + { } + + protected: + tree + do_get_tree(Gogo*) + { return error_mark_node; } + + tree + do_get_init_tree(Gogo*, tree, bool) + { return error_mark_node; } + + Expression* + do_type_descriptor(Gogo*, Named_type*) + { return Expression::make_error(BUILTINS_LOCATION); } + + void + do_reflection(Gogo*, std::string*) const + { gcc_assert(saw_errors()); } + + void + do_mangled_name(Gogo*, std::string* ret) const + { ret->push_back('E'); } +}; + +Type* +Type::make_error_type() +{ + static Error_type singleton_error_type; + return &singleton_error_type; +} + +// The void type. + +class Void_type : public Type +{ + public: + Void_type() + : Type(TYPE_VOID) + { } + + protected: + tree + do_get_tree(Gogo*) + { return void_type_node; } + + tree + do_get_init_tree(Gogo*, tree, bool) + { gcc_unreachable(); } + + Expression* + do_type_descriptor(Gogo*, Named_type*) + { gcc_unreachable(); } + + void + do_reflection(Gogo*, std::string*) const + { } + + void + do_mangled_name(Gogo*, std::string* ret) const + { ret->push_back('v'); } +}; + +Type* +Type::make_void_type() +{ + static Void_type singleton_void_type; + return &singleton_void_type; +} + +// The boolean type. + +class Boolean_type : public Type +{ + public: + Boolean_type() + : Type(TYPE_BOOLEAN) + { } + + protected: + tree + do_get_tree(Gogo*) + { return boolean_type_node; } + + tree + do_get_init_tree(Gogo*, tree type_tree, bool is_clear) + { return is_clear ? NULL : fold_convert(type_tree, boolean_false_node); } + + Expression* + do_type_descriptor(Gogo*, Named_type* name); + + // We should not be asked for the reflection string of a basic type. + void + do_reflection(Gogo*, std::string* ret) const + { ret->append("bool"); } + + void + do_mangled_name(Gogo*, std::string* ret) const + { ret->push_back('b'); } +}; + +// Make the type descriptor. + +Expression* +Boolean_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + if (name != NULL) + return this->plain_type_descriptor(gogo, RUNTIME_TYPE_KIND_BOOL, name); + else + { + Named_object* no = gogo->lookup_global("bool"); + gcc_assert(no != NULL); + return Type::type_descriptor(gogo, no->type_value()); + } +} + +Type* +Type::make_boolean_type() +{ + static Boolean_type boolean_type; + return &boolean_type; +} + +// The named type "bool". + +static Named_type* named_bool_type; + +// Get the named type "bool". + +Named_type* +Type::lookup_bool_type() +{ + return named_bool_type; +} + +// Make the named type "bool". + +Named_type* +Type::make_named_bool_type() +{ + Type* bool_type = Type::make_boolean_type(); + Named_object* named_object = Named_object::make_type("bool", NULL, + bool_type, + BUILTINS_LOCATION); + Named_type* named_type = named_object->type_value(); + named_bool_type = named_type; + return named_type; +} + +// Class Integer_type. + +Integer_type::Named_integer_types Integer_type::named_integer_types; + +// Create a new integer type. Non-abstract integer types always have +// names. + +Named_type* +Integer_type::create_integer_type(const char* name, bool is_unsigned, + int bits, int runtime_type_kind) +{ + Integer_type* integer_type = new Integer_type(false, is_unsigned, bits, + runtime_type_kind); + std::string sname(name); + Named_object* named_object = Named_object::make_type(sname, NULL, + integer_type, + BUILTINS_LOCATION); + Named_type* named_type = named_object->type_value(); + std::pair<Named_integer_types::iterator, bool> ins = + Integer_type::named_integer_types.insert(std::make_pair(sname, named_type)); + gcc_assert(ins.second); + return named_type; +} + +// Look up an existing integer type. + +Named_type* +Integer_type::lookup_integer_type(const char* name) +{ + Named_integer_types::const_iterator p = + Integer_type::named_integer_types.find(name); + gcc_assert(p != Integer_type::named_integer_types.end()); + return p->second; +} + +// Create a new abstract integer type. + +Integer_type* +Integer_type::create_abstract_integer_type() +{ + static Integer_type* abstract_type; + if (abstract_type == NULL) + abstract_type = new Integer_type(true, false, INT_TYPE_SIZE, + RUNTIME_TYPE_KIND_INT); + return abstract_type; +} + +// Integer type compatibility. + +bool +Integer_type::is_identical(const Integer_type* t) const +{ + if (this->is_unsigned_ != t->is_unsigned_ || this->bits_ != t->bits_) + return false; + return this->is_abstract_ == t->is_abstract_; +} + +// Hash code. + +unsigned int +Integer_type::do_hash_for_method(Gogo*) const +{ + return ((this->bits_ << 4) + + ((this->is_unsigned_ ? 1 : 0) << 8) + + ((this->is_abstract_ ? 1 : 0) << 9)); +} + +// Get the tree for an Integer_type. + +tree +Integer_type::do_get_tree(Gogo*) +{ + if (this->is_abstract_) + { + gcc_assert(saw_errors()); + return error_mark_node; + } + + if (this->is_unsigned_) + { + if (this->bits_ == INT_TYPE_SIZE) + return unsigned_type_node; + else if (this->bits_ == CHAR_TYPE_SIZE) + return unsigned_char_type_node; + else if (this->bits_ == SHORT_TYPE_SIZE) + return short_unsigned_type_node; + else if (this->bits_ == LONG_TYPE_SIZE) + return long_unsigned_type_node; + else if (this->bits_ == LONG_LONG_TYPE_SIZE) + return long_long_unsigned_type_node; + else + return make_unsigned_type(this->bits_); + } + else + { + if (this->bits_ == INT_TYPE_SIZE) + return integer_type_node; + else if (this->bits_ == CHAR_TYPE_SIZE) + return signed_char_type_node; + else if (this->bits_ == SHORT_TYPE_SIZE) + return short_integer_type_node; + else if (this->bits_ == LONG_TYPE_SIZE) + return long_integer_type_node; + else if (this->bits_ == LONG_LONG_TYPE_SIZE) + return long_long_integer_type_node; + else + return make_signed_type(this->bits_); + } +} + +tree +Integer_type::do_get_init_tree(Gogo*, tree type_tree, bool is_clear) +{ + return is_clear ? NULL : build_int_cst(type_tree, 0); +} + +// The type descriptor for an integer type. Integer types are always +// named. + +Expression* +Integer_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + gcc_assert(name != NULL); + return this->plain_type_descriptor(gogo, this->runtime_type_kind_, name); +} + +// We should not be asked for the reflection string of a basic type. + +void +Integer_type::do_reflection(Gogo*, std::string*) const +{ + gcc_assert(saw_errors()); +} + +// Mangled name. + +void +Integer_type::do_mangled_name(Gogo*, std::string* ret) const +{ + char buf[100]; + snprintf(buf, sizeof buf, "i%s%s%de", + this->is_abstract_ ? "a" : "", + this->is_unsigned_ ? "u" : "", + this->bits_); + ret->append(buf); +} + +// Make an integer type. + +Named_type* +Type::make_integer_type(const char* name, bool is_unsigned, int bits, + int runtime_type_kind) +{ + return Integer_type::create_integer_type(name, is_unsigned, bits, + runtime_type_kind); +} + +// Make an abstract integer type. + +Integer_type* +Type::make_abstract_integer_type() +{ + return Integer_type::create_abstract_integer_type(); +} + +// Look up an integer type. + +Named_type* +Type::lookup_integer_type(const char* name) +{ + return Integer_type::lookup_integer_type(name); +} + +// Class Float_type. + +Float_type::Named_float_types Float_type::named_float_types; + +// Create a new float type. Non-abstract float types always have +// names. + +Named_type* +Float_type::create_float_type(const char* name, int bits, + int runtime_type_kind) +{ + Float_type* float_type = new Float_type(false, bits, runtime_type_kind); + std::string sname(name); + Named_object* named_object = Named_object::make_type(sname, NULL, float_type, + BUILTINS_LOCATION); + Named_type* named_type = named_object->type_value(); + std::pair<Named_float_types::iterator, bool> ins = + Float_type::named_float_types.insert(std::make_pair(sname, named_type)); + gcc_assert(ins.second); + return named_type; +} + +// Look up an existing float type. + +Named_type* +Float_type::lookup_float_type(const char* name) +{ + Named_float_types::const_iterator p = + Float_type::named_float_types.find(name); + gcc_assert(p != Float_type::named_float_types.end()); + return p->second; +} + +// Create a new abstract float type. + +Float_type* +Float_type::create_abstract_float_type() +{ + static Float_type* abstract_type; + if (abstract_type == NULL) + abstract_type = new Float_type(true, 64, RUNTIME_TYPE_KIND_FLOAT64); + return abstract_type; +} + +// Whether this type is identical with T. + +bool +Float_type::is_identical(const Float_type* t) const +{ + if (this->bits_ != t->bits_) + return false; + return this->is_abstract_ == t->is_abstract_; +} + +// Hash code. + +unsigned int +Float_type::do_hash_for_method(Gogo*) const +{ + return (this->bits_ << 4) + ((this->is_abstract_ ? 1 : 0) << 8); +} + +// Get a tree without using a Gogo*. + +tree +Float_type::type_tree() const +{ + if (this->bits_ == FLOAT_TYPE_SIZE) + return float_type_node; + else if (this->bits_ == DOUBLE_TYPE_SIZE) + return double_type_node; + else if (this->bits_ == LONG_DOUBLE_TYPE_SIZE) + return long_double_type_node; + else + { + tree ret = make_node(REAL_TYPE); + TYPE_PRECISION(ret) = this->bits_; + layout_type(ret); + return ret; + } +} + +// Get a tree. + +tree +Float_type::do_get_tree(Gogo*) +{ + return this->type_tree(); +} + +tree +Float_type::do_get_init_tree(Gogo*, tree type_tree, bool is_clear) +{ + if (is_clear) + return NULL; + REAL_VALUE_TYPE r; + real_from_integer(&r, TYPE_MODE(type_tree), 0, 0, 0); + return build_real(type_tree, r); +} + +// The type descriptor for a float type. Float types are always named. + +Expression* +Float_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + gcc_assert(name != NULL); + return this->plain_type_descriptor(gogo, this->runtime_type_kind_, name); +} + +// We should not be asked for the reflection string of a basic type. + +void +Float_type::do_reflection(Gogo*, std::string*) const +{ + gcc_assert(saw_errors()); +} + +// Mangled name. + +void +Float_type::do_mangled_name(Gogo*, std::string* ret) const +{ + char buf[100]; + snprintf(buf, sizeof buf, "f%s%de", + this->is_abstract_ ? "a" : "", + this->bits_); + ret->append(buf); +} + +// Make a floating point type. + +Named_type* +Type::make_float_type(const char* name, int bits, int runtime_type_kind) +{ + return Float_type::create_float_type(name, bits, runtime_type_kind); +} + +// Make an abstract float type. + +Float_type* +Type::make_abstract_float_type() +{ + return Float_type::create_abstract_float_type(); +} + +// Look up a float type. + +Named_type* +Type::lookup_float_type(const char* name) +{ + return Float_type::lookup_float_type(name); +} + +// Class Complex_type. + +Complex_type::Named_complex_types Complex_type::named_complex_types; + +// Create a new complex type. Non-abstract complex types always have +// names. + +Named_type* +Complex_type::create_complex_type(const char* name, int bits, + int runtime_type_kind) +{ + Complex_type* complex_type = new Complex_type(false, bits, + runtime_type_kind); + std::string sname(name); + Named_object* named_object = Named_object::make_type(sname, NULL, + complex_type, + BUILTINS_LOCATION); + Named_type* named_type = named_object->type_value(); + std::pair<Named_complex_types::iterator, bool> ins = + Complex_type::named_complex_types.insert(std::make_pair(sname, + named_type)); + gcc_assert(ins.second); + return named_type; +} + +// Look up an existing complex type. + +Named_type* +Complex_type::lookup_complex_type(const char* name) +{ + Named_complex_types::const_iterator p = + Complex_type::named_complex_types.find(name); + gcc_assert(p != Complex_type::named_complex_types.end()); + return p->second; +} + +// Create a new abstract complex type. + +Complex_type* +Complex_type::create_abstract_complex_type() +{ + static Complex_type* abstract_type; + if (abstract_type == NULL) + abstract_type = new Complex_type(true, 128, RUNTIME_TYPE_KIND_COMPLEX128); + return abstract_type; +} + +// Whether this type is identical with T. + +bool +Complex_type::is_identical(const Complex_type *t) const +{ + if (this->bits_ != t->bits_) + return false; + return this->is_abstract_ == t->is_abstract_; +} + +// Hash code. + +unsigned int +Complex_type::do_hash_for_method(Gogo*) const +{ + return (this->bits_ << 4) + ((this->is_abstract_ ? 1 : 0) << 8); +} + +// Get a tree without using a Gogo*. + +tree +Complex_type::type_tree() const +{ + if (this->bits_ == FLOAT_TYPE_SIZE * 2) + return complex_float_type_node; + else if (this->bits_ == DOUBLE_TYPE_SIZE * 2) + return complex_double_type_node; + else if (this->bits_ == LONG_DOUBLE_TYPE_SIZE * 2) + return complex_long_double_type_node; + else + { + tree ret = make_node(REAL_TYPE); + TYPE_PRECISION(ret) = this->bits_ / 2; + layout_type(ret); + return build_complex_type(ret); + } +} + +// Get a tree. + +tree +Complex_type::do_get_tree(Gogo*) +{ + return this->type_tree(); +} + +// Zero initializer. + +tree +Complex_type::do_get_init_tree(Gogo*, tree type_tree, bool is_clear) +{ + if (is_clear) + return NULL; + REAL_VALUE_TYPE r; + real_from_integer(&r, TYPE_MODE(TREE_TYPE(type_tree)), 0, 0, 0); + return build_complex(type_tree, build_real(TREE_TYPE(type_tree), r), + build_real(TREE_TYPE(type_tree), r)); +} + +// The type descriptor for a complex type. Complex types are always +// named. + +Expression* +Complex_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + gcc_assert(name != NULL); + return this->plain_type_descriptor(gogo, this->runtime_type_kind_, name); +} + +// We should not be asked for the reflection string of a basic type. + +void +Complex_type::do_reflection(Gogo*, std::string*) const +{ + gcc_assert(saw_errors()); +} + +// Mangled name. + +void +Complex_type::do_mangled_name(Gogo*, std::string* ret) const +{ + char buf[100]; + snprintf(buf, sizeof buf, "c%s%de", + this->is_abstract_ ? "a" : "", + this->bits_); + ret->append(buf); +} + +// Make a complex type. + +Named_type* +Type::make_complex_type(const char* name, int bits, int runtime_type_kind) +{ + return Complex_type::create_complex_type(name, bits, runtime_type_kind); +} + +// Make an abstract complex type. + +Complex_type* +Type::make_abstract_complex_type() +{ + return Complex_type::create_abstract_complex_type(); +} + +// Look up a complex type. + +Named_type* +Type::lookup_complex_type(const char* name) +{ + return Complex_type::lookup_complex_type(name); +} + +// Class String_type. + +// Return the tree for String_type. A string is a struct with two +// fields: a pointer to the characters and a length. + +tree +String_type::do_get_tree(Gogo*) +{ + static tree struct_type; + return Gogo::builtin_struct(&struct_type, "__go_string", NULL_TREE, 2, + "__data", + build_pointer_type(unsigned_char_type_node), + "__length", + integer_type_node); +} + +// Return a tree for the length of STRING. + +tree +String_type::length_tree(Gogo*, tree string) +{ + tree string_type = TREE_TYPE(string); + gcc_assert(TREE_CODE(string_type) == RECORD_TYPE); + tree length_field = DECL_CHAIN(TYPE_FIELDS(string_type)); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(length_field)), + "__length") == 0); + return fold_build3(COMPONENT_REF, integer_type_node, string, + length_field, NULL_TREE); +} + +// Return a tree for a pointer to the bytes of STRING. + +tree +String_type::bytes_tree(Gogo*, tree string) +{ + tree string_type = TREE_TYPE(string); + gcc_assert(TREE_CODE(string_type) == RECORD_TYPE); + tree bytes_field = TYPE_FIELDS(string_type); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(bytes_field)), + "__data") == 0); + return fold_build3(COMPONENT_REF, TREE_TYPE(bytes_field), string, + bytes_field, NULL_TREE); +} + +// We initialize a string to { NULL, 0 }. + +tree +String_type::do_get_init_tree(Gogo*, tree type_tree, bool is_clear) +{ + if (is_clear) + return NULL_TREE; + + gcc_assert(TREE_CODE(type_tree) == RECORD_TYPE); + + VEC(constructor_elt, gc)* init = VEC_alloc(constructor_elt, gc, 2); + + for (tree field = TYPE_FIELDS(type_tree); + field != NULL_TREE; + field = DECL_CHAIN(field)) + { + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), size_zero_node); + } + + tree ret = build_constructor(type_tree, init); + TREE_CONSTANT(ret) = 1; + return ret; +} + +// The type descriptor for the string type. + +Expression* +String_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + if (name != NULL) + return this->plain_type_descriptor(gogo, RUNTIME_TYPE_KIND_STRING, name); + else + { + Named_object* no = gogo->lookup_global("string"); + gcc_assert(no != NULL); + return Type::type_descriptor(gogo, no->type_value()); + } +} + +// We should not be asked for the reflection string of a basic type. + +void +String_type::do_reflection(Gogo*, std::string* ret) const +{ + ret->append("string"); +} + +// Mangled name of a string type. + +void +String_type::do_mangled_name(Gogo*, std::string* ret) const +{ + ret->push_back('z'); +} + +// Make a string type. + +Type* +Type::make_string_type() +{ + static String_type string_type; + return &string_type; +} + +// The named type "string". + +static Named_type* named_string_type; + +// Get the named type "string". + +Named_type* +Type::lookup_string_type() +{ + return named_string_type; +} + +// Make the named type string. + +Named_type* +Type::make_named_string_type() +{ + Type* string_type = Type::make_string_type(); + Named_object* named_object = Named_object::make_type("string", NULL, + string_type, + BUILTINS_LOCATION); + Named_type* named_type = named_object->type_value(); + named_string_type = named_type; + return named_type; +} + +// The sink type. This is the type of the blank identifier _. Any +// type may be assigned to it. + +class Sink_type : public Type +{ + public: + Sink_type() + : Type(TYPE_SINK) + { } + + protected: + tree + do_get_tree(Gogo*) + { gcc_unreachable(); } + + tree + do_get_init_tree(Gogo*, tree, bool) + { gcc_unreachable(); } + + Expression* + do_type_descriptor(Gogo*, Named_type*) + { gcc_unreachable(); } + + void + do_reflection(Gogo*, std::string*) const + { gcc_unreachable(); } + + void + do_mangled_name(Gogo*, std::string*) const + { gcc_unreachable(); } +}; + +// Make the sink type. + +Type* +Type::make_sink_type() +{ + static Sink_type sink_type; + return &sink_type; +} + +// Class Function_type. + +// Traversal. + +int +Function_type::do_traverse(Traverse* traverse) +{ + if (this->receiver_ != NULL + && Type::traverse(this->receiver_->type(), traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (this->parameters_ != NULL + && this->parameters_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (this->results_ != NULL + && this->results_->traverse(traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Returns whether T is a valid redeclaration of this type. If this +// returns false, and REASON is not NULL, *REASON may be set to a +// brief explanation of why it returned false. + +bool +Function_type::is_valid_redeclaration(const Function_type* t, + std::string* reason) const +{ + if (!this->is_identical(t, false, true, reason)) + return false; + + // A redeclaration of a function is required to use the same names + // for the receiver and parameters. + if (this->receiver() != NULL + && this->receiver()->name() != t->receiver()->name() + && this->receiver()->name() != Import::import_marker + && t->receiver()->name() != Import::import_marker) + { + if (reason != NULL) + *reason = "receiver name changed"; + return false; + } + + const Typed_identifier_list* parms1 = this->parameters(); + const Typed_identifier_list* parms2 = t->parameters(); + if (parms1 != NULL) + { + Typed_identifier_list::const_iterator p1 = parms1->begin(); + for (Typed_identifier_list::const_iterator p2 = parms2->begin(); + p2 != parms2->end(); + ++p2, ++p1) + { + if (p1->name() != p2->name() + && p1->name() != Import::import_marker + && p2->name() != Import::import_marker) + { + if (reason != NULL) + *reason = "parameter name changed"; + return false; + } + + // This is called at parse time, so we may have unknown + // types. + Type* t1 = p1->type()->forwarded(); + Type* t2 = p2->type()->forwarded(); + if (t1 != t2 + && t1->forward_declaration_type() != NULL + && (t2->forward_declaration_type() == NULL + || (t1->forward_declaration_type()->named_object() + != t2->forward_declaration_type()->named_object()))) + return false; + } + } + + const Typed_identifier_list* results1 = this->results(); + const Typed_identifier_list* results2 = t->results(); + if (results1 != NULL) + { + Typed_identifier_list::const_iterator res1 = results1->begin(); + for (Typed_identifier_list::const_iterator res2 = results2->begin(); + res2 != results2->end(); + ++res2, ++res1) + { + if (res1->name() != res2->name() + && res1->name() != Import::import_marker + && res2->name() != Import::import_marker) + { + if (reason != NULL) + *reason = "result name changed"; + return false; + } + + // This is called at parse time, so we may have unknown + // types. + Type* t1 = res1->type()->forwarded(); + Type* t2 = res2->type()->forwarded(); + if (t1 != t2 + && t1->forward_declaration_type() != NULL + && (t2->forward_declaration_type() == NULL + || (t1->forward_declaration_type()->named_object() + != t2->forward_declaration_type()->named_object()))) + return false; + } + } + + return true; +} + +// Check whether T is the same as this type. + +bool +Function_type::is_identical(const Function_type* t, bool ignore_receiver, + bool errors_are_identical, + std::string* reason) const +{ + if (!ignore_receiver) + { + const Typed_identifier* r1 = this->receiver(); + const Typed_identifier* r2 = t->receiver(); + if ((r1 != NULL) != (r2 != NULL)) + { + if (reason != NULL) + *reason = _("different receiver types"); + return false; + } + if (r1 != NULL) + { + if (!Type::are_identical(r1->type(), r2->type(), errors_are_identical, + reason)) + { + if (reason != NULL && !reason->empty()) + *reason = "receiver: " + *reason; + return false; + } + } + } + + const Typed_identifier_list* parms1 = this->parameters(); + const Typed_identifier_list* parms2 = t->parameters(); + if ((parms1 != NULL) != (parms2 != NULL)) + { + if (reason != NULL) + *reason = _("different number of parameters"); + return false; + } + if (parms1 != NULL) + { + Typed_identifier_list::const_iterator p1 = parms1->begin(); + for (Typed_identifier_list::const_iterator p2 = parms2->begin(); + p2 != parms2->end(); + ++p2, ++p1) + { + if (p1 == parms1->end()) + { + if (reason != NULL) + *reason = _("different number of parameters"); + return false; + } + + if (!Type::are_identical(p1->type(), p2->type(), + errors_are_identical, NULL)) + { + if (reason != NULL) + *reason = _("different parameter types"); + return false; + } + } + if (p1 != parms1->end()) + { + if (reason != NULL) + *reason = _("different number of parameters"); + return false; + } + } + + if (this->is_varargs() != t->is_varargs()) + { + if (reason != NULL) + *reason = _("different varargs"); + return false; + } + + const Typed_identifier_list* results1 = this->results(); + const Typed_identifier_list* results2 = t->results(); + if ((results1 != NULL) != (results2 != NULL)) + { + if (reason != NULL) + *reason = _("different number of results"); + return false; + } + if (results1 != NULL) + { + Typed_identifier_list::const_iterator res1 = results1->begin(); + for (Typed_identifier_list::const_iterator res2 = results2->begin(); + res2 != results2->end(); + ++res2, ++res1) + { + if (res1 == results1->end()) + { + if (reason != NULL) + *reason = _("different number of results"); + return false; + } + + if (!Type::are_identical(res1->type(), res2->type(), + errors_are_identical, NULL)) + { + if (reason != NULL) + *reason = _("different result types"); + return false; + } + } + if (res1 != results1->end()) + { + if (reason != NULL) + *reason = _("different number of results"); + return false; + } + } + + return true; +} + +// Hash code. + +unsigned int +Function_type::do_hash_for_method(Gogo* gogo) const +{ + unsigned int ret = 0; + // We ignore the receiver type for hash codes, because we need to + // get the same hash code for a method in an interface and a method + // declared for a type. The former will not have a receiver. + if (this->parameters_ != NULL) + { + int shift = 1; + for (Typed_identifier_list::const_iterator p = this->parameters_->begin(); + p != this->parameters_->end(); + ++p, ++shift) + ret += p->type()->hash_for_method(gogo) << shift; + } + if (this->results_ != NULL) + { + int shift = 2; + for (Typed_identifier_list::const_iterator p = this->results_->begin(); + p != this->results_->end(); + ++p, ++shift) + ret += p->type()->hash_for_method(gogo) << shift; + } + if (this->is_varargs_) + ret += 1; + ret <<= 4; + return ret; +} + +// Get the tree for a function type. + +tree +Function_type::do_get_tree(Gogo* gogo) +{ + tree args = NULL_TREE; + tree* pp = &args; + + if (this->receiver_ != NULL) + { + Type* rtype = this->receiver_->type(); + tree ptype = rtype->get_tree(gogo); + if (ptype == error_mark_node) + return error_mark_node; + + // We always pass the address of the receiver parameter, in + // order to make interface calls work with unknown types. + if (rtype->points_to() == NULL) + ptype = build_pointer_type(ptype); + + *pp = tree_cons (NULL_TREE, ptype, NULL_TREE); + pp = &TREE_CHAIN (*pp); + } + + if (this->parameters_ != NULL) + { + for (Typed_identifier_list::const_iterator p = this->parameters_->begin(); + p != this->parameters_->end(); + ++p) + { + tree ptype = p->type()->get_tree(gogo); + if (ptype == error_mark_node) + return error_mark_node; + *pp = tree_cons (NULL_TREE, ptype, NULL_TREE); + pp = &TREE_CHAIN (*pp); + } + } + + // Varargs is handled entirely at the Go level. At the tree level, + // functions are not varargs. + *pp = void_list_node; + + tree result; + if (this->results_ == NULL) + result = void_type_node; + else if (this->results_->size() == 1) + result = this->results_->begin()->type()->get_tree(gogo); + else + { + result = make_node(RECORD_TYPE); + tree field_trees = NULL_TREE; + tree* pp = &field_trees; + for (Typed_identifier_list::const_iterator p = this->results_->begin(); + p != this->results_->end(); + ++p) + { + const std::string name = (p->name().empty() + ? "UNNAMED" + : Gogo::unpack_hidden_name(p->name())); + tree name_tree = get_identifier_with_length(name.data(), + name.length()); + tree field_type_tree = p->type()->get_tree(gogo); + if (field_type_tree == error_mark_node) + return error_mark_node; + tree field = build_decl(this->location_, FIELD_DECL, name_tree, + field_type_tree); + DECL_CONTEXT(field) = result; + *pp = field; + pp = &DECL_CHAIN(field); + } + TYPE_FIELDS(result) = field_trees; + layout_type(result); + } + + if (result == error_mark_node) + return error_mark_node; + + tree fntype = build_function_type(result, args); + if (fntype == error_mark_node) + return fntype; + + return build_pointer_type(fntype); +} + +// Functions are initialized to NULL. + +tree +Function_type::do_get_init_tree(Gogo*, tree type_tree, bool is_clear) +{ + if (is_clear) + return NULL; + return fold_convert(type_tree, null_pointer_node); +} + +// The type of a function type descriptor. + +Type* +Function_type::make_function_type_descriptor_type() +{ + static Type* ret; + if (ret == NULL) + { + Type* tdt = Type::make_type_descriptor_type(); + Type* ptdt = Type::make_type_descriptor_ptr_type(); + + Type* bool_type = Type::lookup_bool_type(); + + Type* slice_type = Type::make_array_type(ptdt, NULL); + + Struct_type* s = Type::make_builtin_struct_type(4, + "", tdt, + "dotdotdot", bool_type, + "in", slice_type, + "out", slice_type); + + ret = Type::make_builtin_named_type("FuncType", s); + } + + return ret; +} + +// The type descriptor for a function type. + +Expression* +Function_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + source_location bloc = BUILTINS_LOCATION; + + Type* ftdt = Function_type::make_function_type_descriptor_type(); + + const Struct_field_list* fields = ftdt->struct_type()->fields(); + + Expression_list* vals = new Expression_list(); + vals->reserve(4); + + Struct_field_list::const_iterator p = fields->begin(); + gcc_assert(p->field_name() == "commonType"); + vals->push_back(this->type_descriptor_constructor(gogo, + RUNTIME_TYPE_KIND_FUNC, + name, NULL, true)); + + ++p; + gcc_assert(p->field_name() == "dotdotdot"); + vals->push_back(Expression::make_boolean(this->is_varargs(), bloc)); + + ++p; + gcc_assert(p->field_name() == "in"); + vals->push_back(this->type_descriptor_params(p->type(), this->receiver(), + this->parameters())); + + ++p; + gcc_assert(p->field_name() == "out"); + vals->push_back(this->type_descriptor_params(p->type(), NULL, + this->results())); + + ++p; + gcc_assert(p == fields->end()); + + return Expression::make_struct_composite_literal(ftdt, vals, bloc); +} + +// Return a composite literal for the parameters or results of a type +// descriptor. + +Expression* +Function_type::type_descriptor_params(Type* params_type, + const Typed_identifier* receiver, + const Typed_identifier_list* params) +{ + source_location bloc = BUILTINS_LOCATION; + + if (receiver == NULL && params == NULL) + return Expression::make_slice_composite_literal(params_type, NULL, bloc); + + Expression_list* vals = new Expression_list(); + vals->reserve((params == NULL ? 0 : params->size()) + + (receiver != NULL ? 1 : 0)); + + if (receiver != NULL) + { + Type* rtype = receiver->type(); + // The receiver is always passed as a pointer. FIXME: Is this + // right? Should that fact affect the type descriptor? + if (rtype->points_to() == NULL) + rtype = Type::make_pointer_type(rtype); + vals->push_back(Expression::make_type_descriptor(rtype, bloc)); + } + + if (params != NULL) + { + for (Typed_identifier_list::const_iterator p = params->begin(); + p != params->end(); + ++p) + vals->push_back(Expression::make_type_descriptor(p->type(), bloc)); + } + + return Expression::make_slice_composite_literal(params_type, vals, bloc); +} + +// The reflection string. + +void +Function_type::do_reflection(Gogo* gogo, std::string* ret) const +{ + // FIXME: Turn this off until we straighten out the type of the + // struct field used in a go statement which calls a method. + // gcc_assert(this->receiver_ == NULL); + + ret->append("func"); + + if (this->receiver_ != NULL) + { + ret->push_back('('); + this->append_reflection(this->receiver_->type(), gogo, ret); + ret->push_back(')'); + } + + ret->push_back('('); + const Typed_identifier_list* params = this->parameters(); + if (params != NULL) + { + bool is_varargs = this->is_varargs_; + for (Typed_identifier_list::const_iterator p = params->begin(); + p != params->end(); + ++p) + { + if (p != params->begin()) + ret->append(", "); + if (!is_varargs || p + 1 != params->end()) + this->append_reflection(p->type(), gogo, ret); + else + { + ret->append("..."); + this->append_reflection(p->type()->array_type()->element_type(), + gogo, ret); + } + } + } + ret->push_back(')'); + + const Typed_identifier_list* results = this->results(); + if (results != NULL && !results->empty()) + { + if (results->size() == 1) + ret->push_back(' '); + else + ret->append(" ("); + for (Typed_identifier_list::const_iterator p = results->begin(); + p != results->end(); + ++p) + { + if (p != results->begin()) + ret->append(", "); + this->append_reflection(p->type(), gogo, ret); + } + if (results->size() > 1) + ret->push_back(')'); + } +} + +// Mangled name. + +void +Function_type::do_mangled_name(Gogo* gogo, std::string* ret) const +{ + ret->push_back('F'); + + if (this->receiver_ != NULL) + { + ret->push_back('m'); + this->append_mangled_name(this->receiver_->type(), gogo, ret); + } + + const Typed_identifier_list* params = this->parameters(); + if (params != NULL) + { + ret->push_back('p'); + for (Typed_identifier_list::const_iterator p = params->begin(); + p != params->end(); + ++p) + this->append_mangled_name(p->type(), gogo, ret); + if (this->is_varargs_) + ret->push_back('V'); + ret->push_back('e'); + } + + const Typed_identifier_list* results = this->results(); + if (results != NULL) + { + ret->push_back('r'); + for (Typed_identifier_list::const_iterator p = results->begin(); + p != results->end(); + ++p) + this->append_mangled_name(p->type(), gogo, ret); + ret->push_back('e'); + } + + ret->push_back('e'); +} + +// Export a function type. + +void +Function_type::do_export(Export* exp) const +{ + // We don't write out the receiver. The only function types which + // should have a receiver are the ones associated with explicitly + // defined methods. For those the receiver type is written out by + // Function::export_func. + + exp->write_c_string("("); + bool first = true; + if (this->parameters_ != NULL) + { + bool is_varargs = this->is_varargs_; + for (Typed_identifier_list::const_iterator p = + this->parameters_->begin(); + p != this->parameters_->end(); + ++p) + { + if (first) + first = false; + else + exp->write_c_string(", "); + if (!is_varargs || p + 1 != this->parameters_->end()) + exp->write_type(p->type()); + else + { + exp->write_c_string("..."); + exp->write_type(p->type()->array_type()->element_type()); + } + } + } + exp->write_c_string(")"); + + const Typed_identifier_list* results = this->results_; + if (results != NULL) + { + exp->write_c_string(" "); + if (results->size() == 1) + exp->write_type(results->begin()->type()); + else + { + first = true; + exp->write_c_string("("); + for (Typed_identifier_list::const_iterator p = results->begin(); + p != results->end(); + ++p) + { + if (first) + first = false; + else + exp->write_c_string(", "); + exp->write_type(p->type()); + } + exp->write_c_string(")"); + } + } +} + +// Import a function type. + +Function_type* +Function_type::do_import(Import* imp) +{ + imp->require_c_string("("); + Typed_identifier_list* parameters; + bool is_varargs = false; + if (imp->peek_char() == ')') + parameters = NULL; + else + { + parameters = new Typed_identifier_list(); + while (true) + { + if (imp->match_c_string("...")) + { + imp->advance(3); + is_varargs = true; + } + + Type* ptype = imp->read_type(); + if (is_varargs) + ptype = Type::make_array_type(ptype, NULL); + parameters->push_back(Typed_identifier(Import::import_marker, + ptype, imp->location())); + if (imp->peek_char() != ',') + break; + gcc_assert(!is_varargs); + imp->require_c_string(", "); + } + } + imp->require_c_string(")"); + + Typed_identifier_list* results; + if (imp->peek_char() != ' ') + results = NULL; + else + { + imp->advance(1); + results = new Typed_identifier_list; + if (imp->peek_char() != '(') + { + Type* rtype = imp->read_type(); + results->push_back(Typed_identifier(Import::import_marker, rtype, + imp->location())); + } + else + { + imp->advance(1); + while (true) + { + Type* rtype = imp->read_type(); + results->push_back(Typed_identifier(Import::import_marker, + rtype, imp->location())); + if (imp->peek_char() != ',') + break; + imp->require_c_string(", "); + } + imp->require_c_string(")"); + } + } + + Function_type* ret = Type::make_function_type(NULL, parameters, results, + imp->location()); + if (is_varargs) + ret->set_is_varargs(); + return ret; +} + +// Make a copy of a function type without a receiver. + +Function_type* +Function_type::copy_without_receiver() const +{ + gcc_assert(this->is_method()); + Function_type *ret = Type::make_function_type(NULL, this->parameters_, + this->results_, + this->location_); + if (this->is_varargs()) + ret->set_is_varargs(); + if (this->is_builtin()) + ret->set_is_builtin(); + return ret; +} + +// Make a copy of a function type with a receiver. + +Function_type* +Function_type::copy_with_receiver(Type* receiver_type) const +{ + gcc_assert(!this->is_method()); + Typed_identifier* receiver = new Typed_identifier("", receiver_type, + this->location_); + return Type::make_function_type(receiver, this->parameters_, + this->results_, this->location_); +} + +// Make a function type. + +Function_type* +Type::make_function_type(Typed_identifier* receiver, + Typed_identifier_list* parameters, + Typed_identifier_list* results, + source_location location) +{ + return new Function_type(receiver, parameters, results, location); +} + +// Class Pointer_type. + +// Traversal. + +int +Pointer_type::do_traverse(Traverse* traverse) +{ + return Type::traverse(this->to_type_, traverse); +} + +// Hash code. + +unsigned int +Pointer_type::do_hash_for_method(Gogo* gogo) const +{ + return this->to_type_->hash_for_method(gogo) << 4; +} + +// The tree for a pointer type. + +tree +Pointer_type::do_get_tree(Gogo* gogo) +{ + return build_pointer_type(this->to_type_->get_tree(gogo)); +} + +// Initialize a pointer type. + +tree +Pointer_type::do_get_init_tree(Gogo*, tree type_tree, bool is_clear) +{ + if (is_clear) + return NULL; + return fold_convert(type_tree, null_pointer_node); +} + +// The type of a pointer type descriptor. + +Type* +Pointer_type::make_pointer_type_descriptor_type() +{ + static Type* ret; + if (ret == NULL) + { + Type* tdt = Type::make_type_descriptor_type(); + Type* ptdt = Type::make_type_descriptor_ptr_type(); + + Struct_type* s = Type::make_builtin_struct_type(2, + "", tdt, + "elem", ptdt); + + ret = Type::make_builtin_named_type("PtrType", s); + } + + return ret; +} + +// The type descriptor for a pointer type. + +Expression* +Pointer_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + if (this->is_unsafe_pointer_type()) + { + gcc_assert(name != NULL); + return this->plain_type_descriptor(gogo, + RUNTIME_TYPE_KIND_UNSAFE_POINTER, + name); + } + else + { + source_location bloc = BUILTINS_LOCATION; + + const Methods* methods; + Type* deref = this->points_to(); + if (deref->named_type() != NULL) + methods = deref->named_type()->methods(); + else if (deref->struct_type() != NULL) + methods = deref->struct_type()->methods(); + else + methods = NULL; + + Type* ptr_tdt = Pointer_type::make_pointer_type_descriptor_type(); + + const Struct_field_list* fields = ptr_tdt->struct_type()->fields(); + + Expression_list* vals = new Expression_list(); + vals->reserve(2); + + Struct_field_list::const_iterator p = fields->begin(); + gcc_assert(p->field_name() == "commonType"); + vals->push_back(this->type_descriptor_constructor(gogo, + RUNTIME_TYPE_KIND_PTR, + name, methods, false)); + + ++p; + gcc_assert(p->field_name() == "elem"); + vals->push_back(Expression::make_type_descriptor(deref, bloc)); + + return Expression::make_struct_composite_literal(ptr_tdt, vals, bloc); + } +} + +// Reflection string. + +void +Pointer_type::do_reflection(Gogo* gogo, std::string* ret) const +{ + ret->push_back('*'); + this->append_reflection(this->to_type_, gogo, ret); +} + +// Mangled name. + +void +Pointer_type::do_mangled_name(Gogo* gogo, std::string* ret) const +{ + ret->push_back('p'); + this->append_mangled_name(this->to_type_, gogo, ret); +} + +// Export. + +void +Pointer_type::do_export(Export* exp) const +{ + exp->write_c_string("*"); + if (this->is_unsafe_pointer_type()) + exp->write_c_string("any"); + else + exp->write_type(this->to_type_); +} + +// Import. + +Pointer_type* +Pointer_type::do_import(Import* imp) +{ + imp->require_c_string("*"); + if (imp->match_c_string("any")) + { + imp->advance(3); + return Type::make_pointer_type(Type::make_void_type()); + } + Type* to = imp->read_type(); + return Type::make_pointer_type(to); +} + +// Make a pointer type. + +Pointer_type* +Type::make_pointer_type(Type* to_type) +{ + typedef Unordered_map(Type*, Pointer_type*) Hashtable; + static Hashtable pointer_types; + Hashtable::const_iterator p = pointer_types.find(to_type); + if (p != pointer_types.end()) + return p->second; + Pointer_type* ret = new Pointer_type(to_type); + pointer_types[to_type] = ret; + return ret; +} + +// The nil type. We use a special type for nil because it is not the +// same as any other type. In C term nil has type void*, but there is +// no such type in Go. + +class Nil_type : public Type +{ + public: + Nil_type() + : Type(TYPE_NIL) + { } + + protected: + tree + do_get_tree(Gogo*) + { return ptr_type_node; } + + tree + do_get_init_tree(Gogo*, tree type_tree, bool is_clear) + { return is_clear ? NULL : fold_convert(type_tree, null_pointer_node); } + + Expression* + do_type_descriptor(Gogo*, Named_type*) + { gcc_unreachable(); } + + void + do_reflection(Gogo*, std::string*) const + { gcc_unreachable(); } + + void + do_mangled_name(Gogo*, std::string* ret) const + { ret->push_back('n'); } +}; + +// Make the nil type. + +Type* +Type::make_nil_type() +{ + static Nil_type singleton_nil_type; + return &singleton_nil_type; +} + +// The type of a function call which returns multiple values. This is +// really a struct, but we don't want to confuse a function call which +// returns a struct with a function call which returns multiple +// values. + +class Call_multiple_result_type : public Type +{ + public: + Call_multiple_result_type(Call_expression* call) + : Type(TYPE_CALL_MULTIPLE_RESULT), + call_(call) + { } + + protected: + bool + do_has_pointer() const + { + gcc_assert(saw_errors()); + return false; + } + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo*, tree, bool) + { + gcc_assert(saw_errors()); + return error_mark_node; + } + + Expression* + do_type_descriptor(Gogo*, Named_type*) + { + gcc_assert(saw_errors()); + return Expression::make_error(UNKNOWN_LOCATION); + } + + void + do_reflection(Gogo*, std::string*) const + { gcc_assert(saw_errors()); } + + void + do_mangled_name(Gogo*, std::string*) const + { gcc_assert(saw_errors()); } + + private: + // The expression being called. + Call_expression* call_; +}; + +// Return the tree for a call result. + +tree +Call_multiple_result_type::do_get_tree(Gogo* gogo) +{ + Function_type* fntype = this->call_->get_function_type(); + gcc_assert(fntype != NULL); + const Typed_identifier_list* results = fntype->results(); + gcc_assert(results != NULL && results->size() > 1); + tree fntype_tree = fntype->get_tree(gogo); + if (fntype_tree == error_mark_node) + return error_mark_node; + return TREE_TYPE(fntype_tree); +} + +// Make a call result type. + +Type* +Type::make_call_multiple_result_type(Call_expression* call) +{ + return new Call_multiple_result_type(call); +} + +// Class Struct_field. + +// Get the name of a field. + +const std::string& +Struct_field::field_name() const +{ + const std::string& name(this->typed_identifier_.name()); + if (!name.empty()) + return name; + else + { + // This is called during parsing, before anything is lowered, so + // we have to be pretty careful to avoid dereferencing an + // unknown type name. + Type* t = this->typed_identifier_.type(); + Type* dt = t; + if (t->classification() == Type::TYPE_POINTER) + { + // Very ugly. + Pointer_type* ptype = static_cast<Pointer_type*>(t); + dt = ptype->points_to(); + } + if (dt->forward_declaration_type() != NULL) + return dt->forward_declaration_type()->name(); + else if (dt->named_type() != NULL) + return dt->named_type()->name(); + else if (t->is_error_type() || dt->is_error_type()) + { + static const std::string error_string = "*error*"; + return error_string; + } + else + { + // Avoid crashing in the erroneous case where T is named but + // DT is not. + gcc_assert(t != dt); + if (t->forward_declaration_type() != NULL) + return t->forward_declaration_type()->name(); + else if (t->named_type() != NULL) + return t->named_type()->name(); + else + gcc_unreachable(); + } + } +} + +// Class Struct_type. + +// Traversal. + +int +Struct_type::do_traverse(Traverse* traverse) +{ + Struct_field_list* fields = this->fields_; + if (fields != NULL) + { + for (Struct_field_list::iterator p = fields->begin(); + p != fields->end(); + ++p) + { + if (Type::traverse(p->type(), traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + } + return TRAVERSE_CONTINUE; +} + +// Verify that the struct type is complete and valid. + +bool +Struct_type::do_verify() +{ + Struct_field_list* fields = this->fields_; + if (fields == NULL) + return true; + bool ret = true; + for (Struct_field_list::iterator p = fields->begin(); + p != fields->end(); + ++p) + { + Type* t = p->type(); + if (t->is_undefined()) + { + error_at(p->location(), "struct field type is incomplete"); + p->set_type(Type::make_error_type()); + ret = false; + } + else if (p->is_anonymous()) + { + if (t->named_type() != NULL && t->points_to() != NULL) + { + error_at(p->location(), "embedded type may not be a pointer"); + p->set_type(Type::make_error_type()); + return false; + } + } + } + return ret; +} + +// Whether this contains a pointer. + +bool +Struct_type::do_has_pointer() const +{ + const Struct_field_list* fields = this->fields(); + if (fields == NULL) + return false; + for (Struct_field_list::const_iterator p = fields->begin(); + p != fields->end(); + ++p) + { + if (p->type()->has_pointer()) + return true; + } + return false; +} + +// Whether this type is identical to T. + +bool +Struct_type::is_identical(const Struct_type* t, + bool errors_are_identical) const +{ + const Struct_field_list* fields1 = this->fields(); + const Struct_field_list* fields2 = t->fields(); + if (fields1 == NULL || fields2 == NULL) + return fields1 == fields2; + Struct_field_list::const_iterator pf2 = fields2->begin(); + for (Struct_field_list::const_iterator pf1 = fields1->begin(); + pf1 != fields1->end(); + ++pf1, ++pf2) + { + if (pf2 == fields2->end()) + return false; + if (pf1->field_name() != pf2->field_name()) + return false; + if (pf1->is_anonymous() != pf2->is_anonymous() + || !Type::are_identical(pf1->type(), pf2->type(), + errors_are_identical, NULL)) + return false; + if (!pf1->has_tag()) + { + if (pf2->has_tag()) + return false; + } + else + { + if (!pf2->has_tag()) + return false; + if (pf1->tag() != pf2->tag()) + return false; + } + } + if (pf2 != fields2->end()) + return false; + return true; +} + +// Whether this struct type has any hidden fields. + +bool +Struct_type::struct_has_hidden_fields(const Named_type* within, + std::string* reason) const +{ + const Struct_field_list* fields = this->fields(); + if (fields == NULL) + return false; + const Package* within_package = (within == NULL + ? NULL + : within->named_object()->package()); + for (Struct_field_list::const_iterator pf = fields->begin(); + pf != fields->end(); + ++pf) + { + if (within_package != NULL + && !pf->is_anonymous() + && Gogo::is_hidden_name(pf->field_name())) + { + if (reason != NULL) + { + std::string within_name = within->named_object()->message_name(); + std::string name = Gogo::message_name(pf->field_name()); + size_t bufsize = 200 + within_name.length() + name.length(); + char* buf = new char[bufsize]; + snprintf(buf, bufsize, + _("implicit assignment of %s%s%s hidden field %s%s%s"), + open_quote, within_name.c_str(), close_quote, + open_quote, name.c_str(), close_quote); + reason->assign(buf); + delete[] buf; + } + return true; + } + + if (pf->type()->has_hidden_fields(within, reason)) + return true; + } + + return false; +} + +// Hash code. + +unsigned int +Struct_type::do_hash_for_method(Gogo* gogo) const +{ + unsigned int ret = 0; + if (this->fields() != NULL) + { + for (Struct_field_list::const_iterator pf = this->fields()->begin(); + pf != this->fields()->end(); + ++pf) + ret = (ret << 1) + pf->type()->hash_for_method(gogo); + } + return ret <<= 2; +} + +// Find the local field NAME. + +const Struct_field* +Struct_type::find_local_field(const std::string& name, + unsigned int *pindex) const +{ + const Struct_field_list* fields = this->fields_; + if (fields == NULL) + return NULL; + unsigned int i = 0; + for (Struct_field_list::const_iterator pf = fields->begin(); + pf != fields->end(); + ++pf, ++i) + { + if (pf->field_name() == name) + { + if (pindex != NULL) + *pindex = i; + return &*pf; + } + } + return NULL; +} + +// Return an expression for field NAME in STRUCT_EXPR, or NULL. + +Field_reference_expression* +Struct_type::field_reference(Expression* struct_expr, const std::string& name, + source_location location) const +{ + unsigned int depth; + return this->field_reference_depth(struct_expr, name, location, NULL, + &depth); +} + +// Return an expression for a field, along with the depth at which it +// was found. + +Field_reference_expression* +Struct_type::field_reference_depth(Expression* struct_expr, + const std::string& name, + source_location location, + Saw_named_type* saw, + unsigned int* depth) const +{ + const Struct_field_list* fields = this->fields_; + if (fields == NULL) + return NULL; + + // Look for a field with this name. + unsigned int i = 0; + for (Struct_field_list::const_iterator pf = fields->begin(); + pf != fields->end(); + ++pf, ++i) + { + if (pf->field_name() == name) + { + *depth = 0; + return Expression::make_field_reference(struct_expr, i, location); + } + } + + // Look for an anonymous field which contains a field with this + // name. + unsigned int found_depth = 0; + Field_reference_expression* ret = NULL; + i = 0; + for (Struct_field_list::const_iterator pf = fields->begin(); + pf != fields->end(); + ++pf, ++i) + { + if (!pf->is_anonymous()) + continue; + + Struct_type* st = pf->type()->deref()->struct_type(); + if (st == NULL) + continue; + + Saw_named_type* hold_saw = saw; + Saw_named_type saw_here; + Named_type* nt = pf->type()->named_type(); + if (nt == NULL) + nt = pf->type()->deref()->named_type(); + if (nt != NULL) + { + Saw_named_type* q; + for (q = saw; q != NULL; q = q->next) + { + if (q->nt == nt) + { + // If this is an error, it will be reported + // elsewhere. + break; + } + } + if (q != NULL) + continue; + saw_here.next = saw; + saw_here.nt = nt; + saw = &saw_here; + } + + // Look for a reference using a NULL struct expression. If we + // find one, fill in the struct expression with a reference to + // this field. + unsigned int subdepth; + Field_reference_expression* sub = st->field_reference_depth(NULL, name, + location, + saw, + &subdepth); + + saw = hold_saw; + + if (sub == NULL) + continue; + + if (ret == NULL || subdepth < found_depth) + { + if (ret != NULL) + delete ret; + ret = sub; + found_depth = subdepth; + Expression* here = Expression::make_field_reference(struct_expr, i, + location); + if (pf->type()->points_to() != NULL) + here = Expression::make_unary(OPERATOR_MULT, here, location); + while (sub->expr() != NULL) + { + sub = sub->expr()->deref()->field_reference_expression(); + gcc_assert(sub != NULL); + } + sub->set_struct_expression(here); + } + else if (subdepth > found_depth) + delete sub; + else + { + // We do not handle ambiguity here--it should be handled by + // Type::bind_field_or_method. + delete sub; + found_depth = 0; + ret = NULL; + } + } + + if (ret != NULL) + *depth = found_depth + 1; + + return ret; +} + +// Return the total number of fields, including embedded fields. + +unsigned int +Struct_type::total_field_count() const +{ + if (this->fields_ == NULL) + return 0; + unsigned int ret = 0; + for (Struct_field_list::const_iterator pf = this->fields_->begin(); + pf != this->fields_->end(); + ++pf) + { + if (!pf->is_anonymous() || pf->type()->deref()->struct_type() == NULL) + ++ret; + else + ret += pf->type()->struct_type()->total_field_count(); + } + return ret; +} + +// Return whether NAME is an unexported field, for better error reporting. + +bool +Struct_type::is_unexported_local_field(Gogo* gogo, + const std::string& name) const +{ + const Struct_field_list* fields = this->fields_; + if (fields != NULL) + { + for (Struct_field_list::const_iterator pf = fields->begin(); + pf != fields->end(); + ++pf) + { + const std::string& field_name(pf->field_name()); + if (Gogo::is_hidden_name(field_name) + && name == Gogo::unpack_hidden_name(field_name) + && gogo->pack_hidden_name(name, false) != field_name) + return true; + } + } + return false; +} + +// Finalize the methods of an unnamed struct. + +void +Struct_type::finalize_methods(Gogo* gogo) +{ + if (this->all_methods_ != NULL) + return; + Type::finalize_methods(gogo, this, this->location_, &this->all_methods_); +} + +// Return the method NAME, or NULL if there isn't one or if it is +// ambiguous. Set *IS_AMBIGUOUS if the method exists but is +// ambiguous. + +Method* +Struct_type::method_function(const std::string& name, bool* is_ambiguous) const +{ + return Type::method_function(this->all_methods_, name, is_ambiguous); +} + +// Get the tree for a struct type. + +tree +Struct_type::do_get_tree(Gogo* gogo) +{ + tree type = make_node(RECORD_TYPE); + return this->fill_in_tree(gogo, type); +} + +// Fill in the fields for a struct type. + +tree +Struct_type::fill_in_tree(Gogo* gogo, tree type) +{ + tree field_trees = NULL_TREE; + tree* pp = &field_trees; + for (Struct_field_list::const_iterator p = this->fields_->begin(); + p != this->fields_->end(); + ++p) + { + std::string name = Gogo::unpack_hidden_name(p->field_name()); + tree name_tree = get_identifier_with_length(name.data(), name.length()); + + tree field_type_tree = p->type()->get_tree(gogo); + if (field_type_tree == error_mark_node) + return error_mark_node; + gcc_assert(TYPE_SIZE(field_type_tree) != NULL_TREE); + + tree field = build_decl(p->location(), FIELD_DECL, name_tree, + field_type_tree); + DECL_CONTEXT(field) = type; + *pp = field; + pp = &DECL_CHAIN(field); + } + + TYPE_FIELDS(type) = field_trees; + + layout_type(type); + + return type; +} + +// Initialize struct fields. + +tree +Struct_type::do_get_init_tree(Gogo* gogo, tree type_tree, bool is_clear) +{ + if (this->fields_ == NULL || this->fields_->empty()) + { + if (is_clear) + return NULL; + else + { + tree ret = build_constructor(type_tree, + VEC_alloc(constructor_elt, gc, 0)); + TREE_CONSTANT(ret) = 1; + return ret; + } + } + + bool is_constant = true; + bool any_fields_set = false; + VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, + this->fields_->size()); + + tree field = TYPE_FIELDS(type_tree); + for (Struct_field_list::const_iterator p = this->fields_->begin(); + p != this->fields_->end(); + ++p, field = DECL_CHAIN(field)) + { + tree value = p->type()->get_init_tree(gogo, is_clear); + if (value == error_mark_node) + return error_mark_node; + gcc_assert(field != NULL_TREE); + if (value != NULL) + { + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + elt->index = field; + elt->value = value; + any_fields_set = true; + if (!TREE_CONSTANT(value)) + is_constant = false; + } + } + gcc_assert(field == NULL_TREE); + + if (!any_fields_set) + { + gcc_assert(is_clear); + VEC_free(constructor_elt, gc, init); + return NULL; + } + + tree ret = build_constructor(type_tree, init); + if (is_constant) + TREE_CONSTANT(ret) = 1; + return ret; +} + +// The type of a struct type descriptor. + +Type* +Struct_type::make_struct_type_descriptor_type() +{ + static Type* ret; + if (ret == NULL) + { + Type* tdt = Type::make_type_descriptor_type(); + Type* ptdt = Type::make_type_descriptor_ptr_type(); + + Type* uintptr_type = Type::lookup_integer_type("uintptr"); + Type* string_type = Type::lookup_string_type(); + Type* pointer_string_type = Type::make_pointer_type(string_type); + + Struct_type* sf = + Type::make_builtin_struct_type(5, + "name", pointer_string_type, + "pkgPath", pointer_string_type, + "typ", ptdt, + "tag", pointer_string_type, + "offset", uintptr_type); + Type* nsf = Type::make_builtin_named_type("structField", sf); + + Type* slice_type = Type::make_array_type(nsf, NULL); + + Struct_type* s = Type::make_builtin_struct_type(2, + "", tdt, + "fields", slice_type); + + ret = Type::make_builtin_named_type("StructType", s); + } + + return ret; +} + +// Build a type descriptor for a struct type. + +Expression* +Struct_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + source_location bloc = BUILTINS_LOCATION; + + Type* stdt = Struct_type::make_struct_type_descriptor_type(); + + const Struct_field_list* fields = stdt->struct_type()->fields(); + + Expression_list* vals = new Expression_list(); + vals->reserve(2); + + const Methods* methods = this->methods(); + // A named struct should not have methods--the methods should attach + // to the named type. + gcc_assert(methods == NULL || name == NULL); + + Struct_field_list::const_iterator ps = fields->begin(); + gcc_assert(ps->field_name() == "commonType"); + vals->push_back(this->type_descriptor_constructor(gogo, + RUNTIME_TYPE_KIND_STRUCT, + name, methods, true)); + + ++ps; + gcc_assert(ps->field_name() == "fields"); + + Expression_list* elements = new Expression_list(); + elements->reserve(this->fields_->size()); + Type* element_type = ps->type()->array_type()->element_type(); + for (Struct_field_list::const_iterator pf = this->fields_->begin(); + pf != this->fields_->end(); + ++pf) + { + const Struct_field_list* f = element_type->struct_type()->fields(); + + Expression_list* fvals = new Expression_list(); + fvals->reserve(5); + + Struct_field_list::const_iterator q = f->begin(); + gcc_assert(q->field_name() == "name"); + if (pf->is_anonymous()) + fvals->push_back(Expression::make_nil(bloc)); + else + { + std::string n = Gogo::unpack_hidden_name(pf->field_name()); + Expression* s = Expression::make_string(n, bloc); + fvals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc)); + } + + ++q; + gcc_assert(q->field_name() == "pkgPath"); + if (!Gogo::is_hidden_name(pf->field_name())) + fvals->push_back(Expression::make_nil(bloc)); + else + { + std::string n = Gogo::hidden_name_prefix(pf->field_name()); + Expression* s = Expression::make_string(n, bloc); + fvals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc)); + } + + ++q; + gcc_assert(q->field_name() == "typ"); + fvals->push_back(Expression::make_type_descriptor(pf->type(), bloc)); + + ++q; + gcc_assert(q->field_name() == "tag"); + if (!pf->has_tag()) + fvals->push_back(Expression::make_nil(bloc)); + else + { + Expression* s = Expression::make_string(pf->tag(), bloc); + fvals->push_back(Expression::make_unary(OPERATOR_AND, s, bloc)); + } + + ++q; + gcc_assert(q->field_name() == "offset"); + fvals->push_back(Expression::make_struct_field_offset(this, &*pf)); + + Expression* v = Expression::make_struct_composite_literal(element_type, + fvals, bloc); + elements->push_back(v); + } + + vals->push_back(Expression::make_slice_composite_literal(ps->type(), + elements, bloc)); + + return Expression::make_struct_composite_literal(stdt, vals, bloc); +} + +// Reflection string. + +void +Struct_type::do_reflection(Gogo* gogo, std::string* ret) const +{ + ret->append("struct { "); + + for (Struct_field_list::const_iterator p = this->fields_->begin(); + p != this->fields_->end(); + ++p) + { + if (p != this->fields_->begin()) + ret->append("; "); + if (p->is_anonymous()) + ret->push_back('?'); + else + ret->append(Gogo::unpack_hidden_name(p->field_name())); + ret->push_back(' '); + this->append_reflection(p->type(), gogo, ret); + + if (p->has_tag()) + { + const std::string& tag(p->tag()); + ret->append(" \""); + for (std::string::const_iterator p = tag.begin(); + p != tag.end(); + ++p) + { + if (*p == '\0') + ret->append("\\x00"); + else if (*p == '\n') + ret->append("\\n"); + else if (*p == '\t') + ret->append("\\t"); + else if (*p == '"') + ret->append("\\\""); + else if (*p == '\\') + ret->append("\\\\"); + else + ret->push_back(*p); + } + ret->push_back('"'); + } + } + + ret->append(" }"); +} + +// Mangled name. + +void +Struct_type::do_mangled_name(Gogo* gogo, std::string* ret) const +{ + ret->push_back('S'); + + const Struct_field_list* fields = this->fields_; + if (fields != NULL) + { + for (Struct_field_list::const_iterator p = fields->begin(); + p != fields->end(); + ++p) + { + if (p->is_anonymous()) + ret->append("0_"); + else + { + std::string n = Gogo::unpack_hidden_name(p->field_name()); + char buf[20]; + snprintf(buf, sizeof buf, "%u_", + static_cast<unsigned int>(n.length())); + ret->append(buf); + ret->append(n); + } + this->append_mangled_name(p->type(), gogo, ret); + if (p->has_tag()) + { + const std::string& tag(p->tag()); + std::string out; + for (std::string::const_iterator p = tag.begin(); + p != tag.end(); + ++p) + { + if (ISALNUM(*p) || *p == '_') + out.push_back(*p); + else + { + char buf[20]; + snprintf(buf, sizeof buf, ".%x.", + static_cast<unsigned int>(*p)); + out.append(buf); + } + } + char buf[20]; + snprintf(buf, sizeof buf, "T%u_", + static_cast<unsigned int>(out.length())); + ret->append(buf); + ret->append(out); + } + } + } + + ret->push_back('e'); +} + +// Export. + +void +Struct_type::do_export(Export* exp) const +{ + exp->write_c_string("struct { "); + const Struct_field_list* fields = this->fields_; + gcc_assert(fields != NULL); + for (Struct_field_list::const_iterator p = fields->begin(); + p != fields->end(); + ++p) + { + if (p->is_anonymous()) + exp->write_string("? "); + else + { + exp->write_string(p->field_name()); + exp->write_c_string(" "); + } + exp->write_type(p->type()); + + if (p->has_tag()) + { + exp->write_c_string(" "); + Expression* expr = Expression::make_string(p->tag(), + BUILTINS_LOCATION); + expr->export_expression(exp); + delete expr; + } + + exp->write_c_string("; "); + } + exp->write_c_string("}"); +} + +// Import. + +Struct_type* +Struct_type::do_import(Import* imp) +{ + imp->require_c_string("struct { "); + Struct_field_list* fields = new Struct_field_list; + if (imp->peek_char() != '}') + { + while (true) + { + std::string name; + if (imp->match_c_string("? ")) + imp->advance(2); + else + { + name = imp->read_identifier(); + imp->require_c_string(" "); + } + Type* ftype = imp->read_type(); + + Struct_field sf(Typed_identifier(name, ftype, imp->location())); + + if (imp->peek_char() == ' ') + { + imp->advance(1); + Expression* expr = Expression::import_expression(imp); + String_expression* sexpr = expr->string_expression(); + gcc_assert(sexpr != NULL); + sf.set_tag(sexpr->val()); + delete sexpr; + } + + imp->require_c_string("; "); + fields->push_back(sf); + if (imp->peek_char() == '}') + break; + } + } + imp->require_c_string("}"); + + return Type::make_struct_type(fields, imp->location()); +} + +// Make a struct type. + +Struct_type* +Type::make_struct_type(Struct_field_list* fields, + source_location location) +{ + return new Struct_type(fields, location); +} + +// Class Array_type. + +// Whether two array types are identical. + +bool +Array_type::is_identical(const Array_type* t, bool errors_are_identical) const +{ + if (!Type::are_identical(this->element_type(), t->element_type(), + errors_are_identical, NULL)) + return false; + + Expression* l1 = this->length(); + Expression* l2 = t->length(); + + // Slices of the same element type are identical. + if (l1 == NULL && l2 == NULL) + return true; + + // Arrays of the same element type are identical if they have the + // same length. + if (l1 != NULL && l2 != NULL) + { + if (l1 == l2) + return true; + + // Try to determine the lengths. If we can't, assume the arrays + // are not identical. + bool ret = false; + mpz_t v1; + mpz_init(v1); + Type* type1; + mpz_t v2; + mpz_init(v2); + Type* type2; + if (l1->integer_constant_value(true, v1, &type1) + && l2->integer_constant_value(true, v2, &type2)) + ret = mpz_cmp(v1, v2) == 0; + mpz_clear(v1); + mpz_clear(v2); + return ret; + } + + // Otherwise the arrays are not identical. + return false; +} + +// Traversal. + +int +Array_type::do_traverse(Traverse* traverse) +{ + if (Type::traverse(this->element_type_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + if (this->length_ != NULL + && Expression::traverse(&this->length_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Check that the length is valid. + +bool +Array_type::verify_length() +{ + if (this->length_ == NULL) + return true; + + Type_context context(Type::lookup_integer_type("int"), false); + this->length_->determine_type(&context); + + if (!this->length_->is_constant()) + { + error_at(this->length_->location(), "array bound is not constant"); + return false; + } + + mpz_t val; + mpz_init(val); + Type* vt; + if (!this->length_->integer_constant_value(true, val, &vt)) + { + mpfr_t fval; + mpfr_init(fval); + if (!this->length_->float_constant_value(fval, &vt)) + { + if (this->length_->type()->integer_type() != NULL + || this->length_->type()->float_type() != NULL) + error_at(this->length_->location(), + "array bound is not constant"); + else + error_at(this->length_->location(), + "array bound is not numeric"); + mpfr_clear(fval); + mpz_clear(val); + return false; + } + if (!mpfr_integer_p(fval)) + { + error_at(this->length_->location(), + "array bound truncated to integer"); + mpfr_clear(fval); + mpz_clear(val); + return false; + } + mpz_init(val); + mpfr_get_z(val, fval, GMP_RNDN); + mpfr_clear(fval); + } + + if (mpz_sgn(val) < 0) + { + error_at(this->length_->location(), "negative array bound"); + mpz_clear(val); + return false; + } + + Type* int_type = Type::lookup_integer_type("int"); + int tbits = int_type->integer_type()->bits(); + int vbits = mpz_sizeinbase(val, 2); + if (vbits + 1 > tbits) + { + error_at(this->length_->location(), "array bound overflows"); + mpz_clear(val); + return false; + } + + mpz_clear(val); + + return true; +} + +// Verify the type. + +bool +Array_type::do_verify() +{ + if (!this->verify_length()) + { + this->length_ = Expression::make_error(this->length_->location()); + return false; + } + return true; +} + +// Array type hash code. + +unsigned int +Array_type::do_hash_for_method(Gogo* gogo) const +{ + // There is no very convenient way to get a hash code for the + // length. + return this->element_type_->hash_for_method(gogo) + 1; +} + +// See if the expression passed to make is suitable. The first +// argument is required, and gives the length. An optional second +// argument is permitted for the capacity. + +bool +Array_type::do_check_make_expression(Expression_list* args, + source_location location) +{ + gcc_assert(this->length_ == NULL); + if (args == NULL || args->empty()) + { + error_at(location, "length required when allocating a slice"); + return false; + } + else if (args->size() > 2) + { + error_at(location, "too many expressions passed to make"); + return false; + } + else + { + if (!Type::check_int_value(args->front(), + _("bad length when making slice"), location)) + return false; + + if (args->size() > 1) + { + if (!Type::check_int_value(args->back(), + _("bad capacity when making slice"), + location)) + return false; + } + + return true; + } +} + +// Get a tree for the length of a fixed array. The length may be +// computed using a function call, so we must only evaluate it once. + +tree +Array_type::get_length_tree(Gogo* gogo) +{ + gcc_assert(this->length_ != NULL); + if (this->length_tree_ == NULL_TREE) + { + mpz_t val; + mpz_init(val); + Type* t; + if (this->length_->integer_constant_value(true, val, &t)) + { + if (t == NULL) + t = Type::lookup_integer_type("int"); + else if (t->is_abstract()) + t = t->make_non_abstract_type(); + tree tt = t->get_tree(gogo); + this->length_tree_ = Expression::integer_constant_tree(val, tt); + mpz_clear(val); + } + else + { + mpz_clear(val); + + // Make up a translation context for the array length + // expression. FIXME: This won't work in general. + Translate_context context(gogo, NULL, NULL, NULL_TREE); + tree len = this->length_->get_tree(&context); + if (len != error_mark_node) + { + len = convert_to_integer(integer_type_node, len); + len = save_expr(len); + } + this->length_tree_ = len; + } + } + return this->length_tree_; +} + +// Get a tree for the type of this array. A fixed array is simply +// represented as ARRAY_TYPE with the appropriate index--i.e., it is +// just like an array in C. An open array is a struct with three +// fields: a data pointer, the length, and the capacity. + +tree +Array_type::do_get_tree(Gogo* gogo) +{ + if (this->length_ == NULL) + { + tree struct_type = gogo->slice_type_tree(void_type_node); + return this->fill_in_slice_tree(gogo, struct_type); + } + else + { + tree array_type = make_node(ARRAY_TYPE); + return this->fill_in_array_tree(gogo, array_type); + } +} + +// Fill in the fields for an array type. This is used for named array +// types. + +tree +Array_type::fill_in_array_tree(Gogo* gogo, tree array_type) +{ + gcc_assert(this->length_ != NULL); + + tree element_type_tree = this->element_type_->get_tree(gogo); + tree length_tree = this->get_length_tree(gogo); + if (element_type_tree == error_mark_node + || length_tree == error_mark_node) + return error_mark_node; + + gcc_assert(TYPE_SIZE(element_type_tree) != NULL_TREE); + + length_tree = fold_convert(sizetype, length_tree); + + // build_index_type takes the maximum index, which is one less than + // the length. + tree index_type = build_index_type(fold_build2(MINUS_EXPR, sizetype, + length_tree, + size_one_node)); + + TREE_TYPE(array_type) = element_type_tree; + TYPE_DOMAIN(array_type) = index_type; + TYPE_ADDR_SPACE(array_type) = TYPE_ADDR_SPACE(element_type_tree); + layout_type(array_type); + + if (TYPE_STRUCTURAL_EQUALITY_P(element_type_tree) + || TYPE_STRUCTURAL_EQUALITY_P(index_type)) + SET_TYPE_STRUCTURAL_EQUALITY(array_type); + else if (TYPE_CANONICAL(element_type_tree) != element_type_tree + || TYPE_CANONICAL(index_type) != index_type) + TYPE_CANONICAL(array_type) = + build_array_type(TYPE_CANONICAL(element_type_tree), + TYPE_CANONICAL(index_type)); + + return array_type; +} + +// Fill in the fields for a slice type. This is used for named slice +// types. + +tree +Array_type::fill_in_slice_tree(Gogo* gogo, tree struct_type) +{ + gcc_assert(this->length_ == NULL); + + tree element_type_tree = this->element_type_->get_tree(gogo); + if (element_type_tree == error_mark_node) + return error_mark_node; + tree field = TYPE_FIELDS(struct_type); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__values") == 0); + gcc_assert(POINTER_TYPE_P(TREE_TYPE(field)) + && TREE_TYPE(TREE_TYPE(field)) == void_type_node); + TREE_TYPE(field) = build_pointer_type(element_type_tree); + + return struct_type; +} + +// Return an initializer for an array type. + +tree +Array_type::do_get_init_tree(Gogo* gogo, tree type_tree, bool is_clear) +{ + if (this->length_ == NULL) + { + // Open array. + + if (is_clear) + return NULL; + + gcc_assert(TREE_CODE(type_tree) == RECORD_TYPE); + + VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 3); + + for (tree field = TYPE_FIELDS(type_tree); + field != NULL_TREE; + field = DECL_CHAIN(field)) + { + constructor_elt* elt = VEC_quick_push(constructor_elt, init, + NULL); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), size_zero_node); + } + + tree ret = build_constructor(type_tree, init); + TREE_CONSTANT(ret) = 1; + return ret; + } + else + { + // Fixed array. + + tree value = this->element_type_->get_init_tree(gogo, is_clear); + if (value == NULL) + return NULL; + if (value == error_mark_node) + return error_mark_node; + + tree length_tree = this->get_length_tree(gogo); + if (length_tree == error_mark_node) + return error_mark_node; + + length_tree = fold_convert(sizetype, length_tree); + tree range = build2(RANGE_EXPR, sizetype, size_zero_node, + fold_build2(MINUS_EXPR, sizetype, + length_tree, size_one_node)); + tree ret = build_constructor_single(type_tree, range, value); + if (TREE_CONSTANT(value)) + TREE_CONSTANT(ret) = 1; + return ret; + } +} + +// Handle the builtin make function for a slice. + +tree +Array_type::do_make_expression_tree(Translate_context* context, + Expression_list* args, + source_location location) +{ + gcc_assert(this->length_ == NULL); + + Gogo* gogo = context->gogo(); + tree type_tree = this->get_tree(gogo); + if (type_tree == error_mark_node) + return error_mark_node; + + tree values_field = TYPE_FIELDS(type_tree); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(values_field)), + "__values") == 0); + + tree count_field = DECL_CHAIN(values_field); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(count_field)), + "__count") == 0); + + tree element_type_tree = this->element_type_->get_tree(gogo); + if (element_type_tree == error_mark_node) + return error_mark_node; + tree element_size_tree = TYPE_SIZE_UNIT(element_type_tree); + + tree value = this->element_type_->get_init_tree(gogo, true); + if (value == error_mark_node) + return error_mark_node; + + // The first argument is the number of elements, the optional second + // argument is the capacity. + gcc_assert(args != NULL && args->size() >= 1 && args->size() <= 2); + + tree length_tree = args->front()->get_tree(context); + if (length_tree == error_mark_node) + return error_mark_node; + if (!DECL_P(length_tree)) + length_tree = save_expr(length_tree); + if (!INTEGRAL_TYPE_P(TREE_TYPE(length_tree))) + length_tree = convert_to_integer(TREE_TYPE(count_field), length_tree); + + tree bad_index = Expression::check_bounds(length_tree, + TREE_TYPE(count_field), + NULL_TREE, location); + + length_tree = fold_convert_loc(location, TREE_TYPE(count_field), length_tree); + tree capacity_tree; + if (args->size() == 1) + capacity_tree = length_tree; + else + { + capacity_tree = args->back()->get_tree(context); + if (capacity_tree == error_mark_node) + return error_mark_node; + if (!DECL_P(capacity_tree)) + capacity_tree = save_expr(capacity_tree); + if (!INTEGRAL_TYPE_P(TREE_TYPE(capacity_tree))) + capacity_tree = convert_to_integer(TREE_TYPE(count_field), + capacity_tree); + + bad_index = Expression::check_bounds(capacity_tree, + TREE_TYPE(count_field), + bad_index, location); + + tree chktype = (((TYPE_SIZE(TREE_TYPE(capacity_tree)) + > TYPE_SIZE(TREE_TYPE(length_tree))) + || ((TYPE_SIZE(TREE_TYPE(capacity_tree)) + == TYPE_SIZE(TREE_TYPE(length_tree))) + && TYPE_UNSIGNED(TREE_TYPE(capacity_tree)))) + ? TREE_TYPE(capacity_tree) + : TREE_TYPE(length_tree)); + tree chk = fold_build2_loc(location, LT_EXPR, boolean_type_node, + fold_convert_loc(location, chktype, + capacity_tree), + fold_convert_loc(location, chktype, + length_tree)); + if (bad_index == NULL_TREE) + bad_index = chk; + else + bad_index = fold_build2_loc(location, TRUTH_OR_EXPR, boolean_type_node, + bad_index, chk); + + capacity_tree = fold_convert_loc(location, TREE_TYPE(count_field), + capacity_tree); + } + + tree size_tree = fold_build2_loc(location, MULT_EXPR, sizetype, + element_size_tree, + fold_convert_loc(location, sizetype, + capacity_tree)); + + tree chk = fold_build2_loc(location, TRUTH_AND_EXPR, boolean_type_node, + fold_build2_loc(location, GT_EXPR, + boolean_type_node, + fold_convert_loc(location, + sizetype, + capacity_tree), + size_zero_node), + fold_build2_loc(location, LT_EXPR, + boolean_type_node, + size_tree, element_size_tree)); + if (bad_index == NULL_TREE) + bad_index = chk; + else + bad_index = fold_build2_loc(location, TRUTH_OR_EXPR, boolean_type_node, + bad_index, chk); + + tree space = context->gogo()->allocate_memory(this->element_type_, + size_tree, location); + + if (value != NULL_TREE) + space = save_expr(space); + + space = fold_convert(TREE_TYPE(values_field), space); + + if (bad_index != NULL_TREE && bad_index != boolean_false_node) + { + tree crash = Gogo::runtime_error(RUNTIME_ERROR_MAKE_SLICE_OUT_OF_BOUNDS, + location); + space = build2(COMPOUND_EXPR, TREE_TYPE(space), + build3(COND_EXPR, void_type_node, + bad_index, crash, NULL_TREE), + space); + } + + tree constructor = gogo->slice_constructor(type_tree, space, length_tree, + capacity_tree); + + if (value == NULL_TREE) + { + // The array contents are zero initialized. + return constructor; + } + + // The elements must be initialized. + + tree max = fold_build2_loc(location, MINUS_EXPR, TREE_TYPE(count_field), + capacity_tree, + fold_convert_loc(location, TREE_TYPE(count_field), + integer_one_node)); + + tree array_type = build_array_type(element_type_tree, + build_index_type(max)); + + tree value_pointer = fold_convert_loc(location, + build_pointer_type(array_type), + space); + + tree range = build2(RANGE_EXPR, sizetype, size_zero_node, max); + tree space_init = build_constructor_single(array_type, range, value); + + return build2(COMPOUND_EXPR, TREE_TYPE(constructor), + build2(MODIFY_EXPR, void_type_node, + build_fold_indirect_ref(value_pointer), + space_init), + constructor); +} + +// Return a tree for a pointer to the values in ARRAY. + +tree +Array_type::value_pointer_tree(Gogo*, tree array) const +{ + tree ret; + if (this->length() != NULL) + { + // Fixed array. + ret = fold_convert(build_pointer_type(TREE_TYPE(TREE_TYPE(array))), + build_fold_addr_expr(array)); + } + else + { + // Open array. + tree field = TYPE_FIELDS(TREE_TYPE(array)); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), + "__values") == 0); + ret = fold_build3(COMPONENT_REF, TREE_TYPE(field), array, field, + NULL_TREE); + } + if (TREE_CONSTANT(array)) + TREE_CONSTANT(ret) = 1; + return ret; +} + +// Return a tree for the length of the array ARRAY which has this +// type. + +tree +Array_type::length_tree(Gogo* gogo, tree array) +{ + if (this->length_ != NULL) + { + if (TREE_CODE(array) == SAVE_EXPR) + return fold_convert(integer_type_node, this->get_length_tree(gogo)); + else + return omit_one_operand(integer_type_node, + this->get_length_tree(gogo), array); + } + + // This is an open array. We need to read the length field. + + tree type = TREE_TYPE(array); + gcc_assert(TREE_CODE(type) == RECORD_TYPE); + + tree field = DECL_CHAIN(TYPE_FIELDS(type)); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__count") == 0); + + tree ret = build3(COMPONENT_REF, TREE_TYPE(field), array, field, NULL_TREE); + if (TREE_CONSTANT(array)) + TREE_CONSTANT(ret) = 1; + return ret; +} + +// Return a tree for the capacity of the array ARRAY which has this +// type. + +tree +Array_type::capacity_tree(Gogo* gogo, tree array) +{ + if (this->length_ != NULL) + return omit_one_operand(sizetype, this->get_length_tree(gogo), array); + + // This is an open array. We need to read the capacity field. + + tree type = TREE_TYPE(array); + gcc_assert(TREE_CODE(type) == RECORD_TYPE); + + tree field = DECL_CHAIN(DECL_CHAIN(TYPE_FIELDS(type))); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__capacity") == 0); + + return build3(COMPONENT_REF, TREE_TYPE(field), array, field, NULL_TREE); +} + +// Export. + +void +Array_type::do_export(Export* exp) const +{ + exp->write_c_string("["); + if (this->length_ != NULL) + this->length_->export_expression(exp); + exp->write_c_string("] "); + exp->write_type(this->element_type_); +} + +// Import. + +Array_type* +Array_type::do_import(Import* imp) +{ + imp->require_c_string("["); + Expression* length; + if (imp->peek_char() == ']') + length = NULL; + else + length = Expression::import_expression(imp); + imp->require_c_string("] "); + Type* element_type = imp->read_type(); + return Type::make_array_type(element_type, length); +} + +// The type of an array type descriptor. + +Type* +Array_type::make_array_type_descriptor_type() +{ + static Type* ret; + if (ret == NULL) + { + Type* tdt = Type::make_type_descriptor_type(); + Type* ptdt = Type::make_type_descriptor_ptr_type(); + + Type* uintptr_type = Type::lookup_integer_type("uintptr"); + + Struct_type* sf = + Type::make_builtin_struct_type(3, + "", tdt, + "elem", ptdt, + "len", uintptr_type); + + ret = Type::make_builtin_named_type("ArrayType", sf); + } + + return ret; +} + +// The type of an slice type descriptor. + +Type* +Array_type::make_slice_type_descriptor_type() +{ + static Type* ret; + if (ret == NULL) + { + Type* tdt = Type::make_type_descriptor_type(); + Type* ptdt = Type::make_type_descriptor_ptr_type(); + + Struct_type* sf = + Type::make_builtin_struct_type(2, + "", tdt, + "elem", ptdt); + + ret = Type::make_builtin_named_type("SliceType", sf); + } + + return ret; +} + +// Build a type descriptor for an array/slice type. + +Expression* +Array_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + if (this->length_ != NULL) + return this->array_type_descriptor(gogo, name); + else + return this->slice_type_descriptor(gogo, name); +} + +// Build a type descriptor for an array type. + +Expression* +Array_type::array_type_descriptor(Gogo* gogo, Named_type* name) +{ + source_location bloc = BUILTINS_LOCATION; + + Type* atdt = Array_type::make_array_type_descriptor_type(); + + const Struct_field_list* fields = atdt->struct_type()->fields(); + + Expression_list* vals = new Expression_list(); + vals->reserve(3); + + Struct_field_list::const_iterator p = fields->begin(); + gcc_assert(p->field_name() == "commonType"); + vals->push_back(this->type_descriptor_constructor(gogo, + RUNTIME_TYPE_KIND_ARRAY, + name, NULL, true)); + + ++p; + gcc_assert(p->field_name() == "elem"); + vals->push_back(Expression::make_type_descriptor(this->element_type_, bloc)); + + ++p; + gcc_assert(p->field_name() == "len"); + vals->push_back(Expression::make_cast(p->type(), this->length_, bloc)); + + ++p; + gcc_assert(p == fields->end()); + + return Expression::make_struct_composite_literal(atdt, vals, bloc); +} + +// Build a type descriptor for a slice type. + +Expression* +Array_type::slice_type_descriptor(Gogo* gogo, Named_type* name) +{ + source_location bloc = BUILTINS_LOCATION; + + Type* stdt = Array_type::make_slice_type_descriptor_type(); + + const Struct_field_list* fields = stdt->struct_type()->fields(); + + Expression_list* vals = new Expression_list(); + vals->reserve(2); + + Struct_field_list::const_iterator p = fields->begin(); + gcc_assert(p->field_name() == "commonType"); + vals->push_back(this->type_descriptor_constructor(gogo, + RUNTIME_TYPE_KIND_SLICE, + name, NULL, true)); + + ++p; + gcc_assert(p->field_name() == "elem"); + vals->push_back(Expression::make_type_descriptor(this->element_type_, bloc)); + + ++p; + gcc_assert(p == fields->end()); + + return Expression::make_struct_composite_literal(stdt, vals, bloc); +} + +// Reflection string. + +void +Array_type::do_reflection(Gogo* gogo, std::string* ret) const +{ + ret->push_back('['); + if (this->length_ != NULL) + { + mpz_t val; + mpz_init(val); + Type* type; + if (!this->length_->integer_constant_value(true, val, &type)) + error_at(this->length_->location(), + "array length must be integer constant expression"); + else if (mpz_cmp_si(val, 0) < 0) + error_at(this->length_->location(), "array length is negative"); + else if (mpz_cmp_ui(val, mpz_get_ui(val)) != 0) + error_at(this->length_->location(), "array length is too large"); + else + { + char buf[50]; + snprintf(buf, sizeof buf, "%lu", mpz_get_ui(val)); + ret->append(buf); + } + mpz_clear(val); + } + ret->push_back(']'); + + this->append_reflection(this->element_type_, gogo, ret); +} + +// Mangled name. + +void +Array_type::do_mangled_name(Gogo* gogo, std::string* ret) const +{ + ret->push_back('A'); + this->append_mangled_name(this->element_type_, gogo, ret); + if (this->length_ != NULL) + { + mpz_t val; + mpz_init(val); + Type* type; + if (!this->length_->integer_constant_value(true, val, &type)) + error_at(this->length_->location(), + "array length must be integer constant expression"); + else if (mpz_cmp_si(val, 0) < 0) + error_at(this->length_->location(), "array length is negative"); + else if (mpz_cmp_ui(val, mpz_get_ui(val)) != 0) + error_at(this->length_->location(), "array size is too large"); + else + { + char buf[50]; + snprintf(buf, sizeof buf, "%lu", mpz_get_ui(val)); + ret->append(buf); + } + mpz_clear(val); + } + ret->push_back('e'); +} + +// Make an array type. + +Array_type* +Type::make_array_type(Type* element_type, Expression* length) +{ + return new Array_type(element_type, length); +} + +// Class Map_type. + +// Traversal. + +int +Map_type::do_traverse(Traverse* traverse) +{ + if (Type::traverse(this->key_type_, traverse) == TRAVERSE_EXIT + || Type::traverse(this->val_type_, traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Check that the map type is OK. + +bool +Map_type::do_verify() +{ + if (this->key_type_->struct_type() != NULL + || this->key_type_->array_type() != NULL) + { + error_at(this->location_, "invalid map key type"); + return false; + } + return true; +} + +// Whether two map types are identical. + +bool +Map_type::is_identical(const Map_type* t, bool errors_are_identical) const +{ + return (Type::are_identical(this->key_type(), t->key_type(), + errors_are_identical, NULL) + && Type::are_identical(this->val_type(), t->val_type(), + errors_are_identical, NULL)); +} + +// Hash code. + +unsigned int +Map_type::do_hash_for_method(Gogo* gogo) const +{ + return (this->key_type_->hash_for_method(gogo) + + this->val_type_->hash_for_method(gogo) + + 2); +} + +// Check that a call to the builtin make function is valid. For a map +// the optional argument is the number of spaces to preallocate for +// values. + +bool +Map_type::do_check_make_expression(Expression_list* args, + source_location location) +{ + if (args != NULL && !args->empty()) + { + if (!Type::check_int_value(args->front(), _("bad size when making map"), + location)) + return false; + else if (args->size() > 1) + { + error_at(location, "too many arguments when making map"); + return false; + } + } + return true; +} + +// Get a tree for a map type. A map type is represented as a pointer +// to a struct. The struct is __go_map in libgo/map.h. + +tree +Map_type::do_get_tree(Gogo* gogo) +{ + static tree type_tree; + if (type_tree == NULL_TREE) + { + tree struct_type = make_node(RECORD_TYPE); + + tree map_descriptor_type = gogo->map_descriptor_type(); + tree const_map_descriptor_type = + build_qualified_type(map_descriptor_type, TYPE_QUAL_CONST); + tree name = get_identifier("__descriptor"); + tree field = build_decl(BUILTINS_LOCATION, FIELD_DECL, name, + build_pointer_type(const_map_descriptor_type)); + DECL_CONTEXT(field) = struct_type; + TYPE_FIELDS(struct_type) = field; + tree last_field = field; + + name = get_identifier("__element_count"); + field = build_decl(BUILTINS_LOCATION, FIELD_DECL, name, sizetype); + DECL_CONTEXT(field) = struct_type; + DECL_CHAIN(last_field) = field; + last_field = field; + + name = get_identifier("__bucket_count"); + field = build_decl(BUILTINS_LOCATION, FIELD_DECL, name, sizetype); + DECL_CONTEXT(field) = struct_type; + DECL_CHAIN(last_field) = field; + last_field = field; + + name = get_identifier("__buckets"); + field = build_decl(BUILTINS_LOCATION, FIELD_DECL, name, + build_pointer_type(ptr_type_node)); + DECL_CONTEXT(field) = struct_type; + DECL_CHAIN(last_field) = field; + + layout_type(struct_type); + + // Give the struct a name for better debugging info. + name = get_identifier("__go_map"); + tree type_decl = build_decl(BUILTINS_LOCATION, TYPE_DECL, name, + struct_type); + DECL_ARTIFICIAL(type_decl) = 1; + TYPE_NAME(struct_type) = type_decl; + go_preserve_from_gc(type_decl); + rest_of_decl_compilation(type_decl, 1, 0); + + type_tree = build_pointer_type(struct_type); + go_preserve_from_gc(type_tree); + } + + return type_tree; +} + +// Initialize a map. + +tree +Map_type::do_get_init_tree(Gogo*, tree type_tree, bool is_clear) +{ + if (is_clear) + return NULL; + return fold_convert(type_tree, null_pointer_node); +} + +// Return an expression for a newly allocated map. + +tree +Map_type::do_make_expression_tree(Translate_context* context, + Expression_list* args, + source_location location) +{ + tree bad_index = NULL_TREE; + + tree expr_tree; + if (args == NULL || args->empty()) + expr_tree = size_zero_node; + else + { + expr_tree = args->front()->get_tree(context); + if (expr_tree == error_mark_node) + return error_mark_node; + if (!DECL_P(expr_tree)) + expr_tree = save_expr(expr_tree); + if (!INTEGRAL_TYPE_P(TREE_TYPE(expr_tree))) + expr_tree = convert_to_integer(sizetype, expr_tree); + bad_index = Expression::check_bounds(expr_tree, sizetype, bad_index, + location); + } + + tree map_type = this->get_tree(context->gogo()); + + static tree new_map_fndecl; + tree ret = Gogo::call_builtin(&new_map_fndecl, + location, + "__go_new_map", + 2, + map_type, + TREE_TYPE(TYPE_FIELDS(TREE_TYPE(map_type))), + context->gogo()->map_descriptor(this), + sizetype, + expr_tree); + if (ret == error_mark_node) + return error_mark_node; + // This can panic if the capacity is out of range. + TREE_NOTHROW(new_map_fndecl) = 0; + + if (bad_index == NULL_TREE) + return ret; + else + { + tree crash = Gogo::runtime_error(RUNTIME_ERROR_MAKE_MAP_OUT_OF_BOUNDS, + location); + return build2(COMPOUND_EXPR, TREE_TYPE(ret), + build3(COND_EXPR, void_type_node, + bad_index, crash, NULL_TREE), + ret); + } +} + +// The type of a map type descriptor. + +Type* +Map_type::make_map_type_descriptor_type() +{ + static Type* ret; + if (ret == NULL) + { + Type* tdt = Type::make_type_descriptor_type(); + Type* ptdt = Type::make_type_descriptor_ptr_type(); + + Struct_type* sf = + Type::make_builtin_struct_type(3, + "", tdt, + "key", ptdt, + "elem", ptdt); + + ret = Type::make_builtin_named_type("MapType", sf); + } + + return ret; +} + +// Build a type descriptor for a map type. + +Expression* +Map_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + source_location bloc = BUILTINS_LOCATION; + + Type* mtdt = Map_type::make_map_type_descriptor_type(); + + const Struct_field_list* fields = mtdt->struct_type()->fields(); + + Expression_list* vals = new Expression_list(); + vals->reserve(3); + + Struct_field_list::const_iterator p = fields->begin(); + gcc_assert(p->field_name() == "commonType"); + vals->push_back(this->type_descriptor_constructor(gogo, + RUNTIME_TYPE_KIND_MAP, + name, NULL, true)); + + ++p; + gcc_assert(p->field_name() == "key"); + vals->push_back(Expression::make_type_descriptor(this->key_type_, bloc)); + + ++p; + gcc_assert(p->field_name() == "elem"); + vals->push_back(Expression::make_type_descriptor(this->val_type_, bloc)); + + ++p; + gcc_assert(p == fields->end()); + + return Expression::make_struct_composite_literal(mtdt, vals, bloc); +} + +// Reflection string for a map. + +void +Map_type::do_reflection(Gogo* gogo, std::string* ret) const +{ + ret->append("map["); + this->append_reflection(this->key_type_, gogo, ret); + ret->append("] "); + this->append_reflection(this->val_type_, gogo, ret); +} + +// Mangled name for a map. + +void +Map_type::do_mangled_name(Gogo* gogo, std::string* ret) const +{ + ret->push_back('M'); + this->append_mangled_name(this->key_type_, gogo, ret); + ret->append("__"); + this->append_mangled_name(this->val_type_, gogo, ret); +} + +// Export a map type. + +void +Map_type::do_export(Export* exp) const +{ + exp->write_c_string("map ["); + exp->write_type(this->key_type_); + exp->write_c_string("] "); + exp->write_type(this->val_type_); +} + +// Import a map type. + +Map_type* +Map_type::do_import(Import* imp) +{ + imp->require_c_string("map ["); + Type* key_type = imp->read_type(); + imp->require_c_string("] "); + Type* val_type = imp->read_type(); + return Type::make_map_type(key_type, val_type, imp->location()); +} + +// Make a map type. + +Map_type* +Type::make_map_type(Type* key_type, Type* val_type, source_location location) +{ + return new Map_type(key_type, val_type, location); +} + +// Class Channel_type. + +// Hash code. + +unsigned int +Channel_type::do_hash_for_method(Gogo* gogo) const +{ + unsigned int ret = 0; + if (this->may_send_) + ret += 1; + if (this->may_receive_) + ret += 2; + if (this->element_type_ != NULL) + ret += this->element_type_->hash_for_method(gogo) << 2; + return ret << 3; +} + +// Whether this type is the same as T. + +bool +Channel_type::is_identical(const Channel_type* t, + bool errors_are_identical) const +{ + if (!Type::are_identical(this->element_type(), t->element_type(), + errors_are_identical, NULL)) + return false; + return (this->may_send_ == t->may_send_ + && this->may_receive_ == t->may_receive_); +} + +// Check whether the parameters for a call to the builtin function +// make are OK for a channel. A channel can take an optional single +// parameter which is the buffer size. + +bool +Channel_type::do_check_make_expression(Expression_list* args, + source_location location) +{ + if (args != NULL && !args->empty()) + { + if (!Type::check_int_value(args->front(), + _("bad buffer size when making channel"), + location)) + return false; + else if (args->size() > 1) + { + error_at(location, "too many arguments when making channel"); + return false; + } + } + return true; +} + +// Return the tree for a channel type. A channel is a pointer to a +// __go_channel struct. The __go_channel struct is defined in +// libgo/runtime/channel.h. + +tree +Channel_type::do_get_tree(Gogo*) +{ + static tree type_tree; + if (type_tree == NULL_TREE) + { + tree ret = make_node(RECORD_TYPE); + TYPE_NAME(ret) = get_identifier("__go_channel"); + TYPE_STUB_DECL(ret) = build_decl(BUILTINS_LOCATION, TYPE_DECL, NULL_TREE, + ret); + type_tree = build_pointer_type(ret); + go_preserve_from_gc(type_tree); + } + return type_tree; +} + +// Initialize a channel variable. + +tree +Channel_type::do_get_init_tree(Gogo*, tree type_tree, bool is_clear) +{ + if (is_clear) + return NULL; + return fold_convert(type_tree, null_pointer_node); +} + +// Handle the builtin function make for a channel. + +tree +Channel_type::do_make_expression_tree(Translate_context* context, + Expression_list* args, + source_location location) +{ + Gogo* gogo = context->gogo(); + tree channel_type = this->get_tree(gogo); + + tree element_tree = this->element_type_->get_tree(gogo); + tree element_size_tree = size_in_bytes(element_tree); + + tree bad_index = NULL_TREE; + + tree expr_tree; + if (args == NULL || args->empty()) + expr_tree = size_zero_node; + else + { + expr_tree = args->front()->get_tree(context); + if (expr_tree == error_mark_node) + return error_mark_node; + if (!DECL_P(expr_tree)) + expr_tree = save_expr(expr_tree); + if (!INTEGRAL_TYPE_P(TREE_TYPE(expr_tree))) + expr_tree = convert_to_integer(sizetype, expr_tree); + bad_index = Expression::check_bounds(expr_tree, sizetype, bad_index, + location); + } + + static tree new_channel_fndecl; + tree ret = Gogo::call_builtin(&new_channel_fndecl, + location, + "__go_new_channel", + 2, + channel_type, + sizetype, + element_size_tree, + sizetype, + expr_tree); + if (ret == error_mark_node) + return error_mark_node; + // This can panic if the capacity is out of range. + TREE_NOTHROW(new_channel_fndecl) = 0; + + if (bad_index == NULL_TREE) + return ret; + else + { + tree crash = Gogo::runtime_error(RUNTIME_ERROR_MAKE_CHAN_OUT_OF_BOUNDS, + location); + return build2(COMPOUND_EXPR, TREE_TYPE(ret), + build3(COND_EXPR, void_type_node, + bad_index, crash, NULL_TREE), + ret); + } +} + +// Build a type descriptor for a channel type. + +Type* +Channel_type::make_chan_type_descriptor_type() +{ + static Type* ret; + if (ret == NULL) + { + Type* tdt = Type::make_type_descriptor_type(); + Type* ptdt = Type::make_type_descriptor_ptr_type(); + + Type* uintptr_type = Type::lookup_integer_type("uintptr"); + + Struct_type* sf = + Type::make_builtin_struct_type(3, + "", tdt, + "elem", ptdt, + "dir", uintptr_type); + + ret = Type::make_builtin_named_type("ChanType", sf); + } + + return ret; +} + +// Build a type descriptor for a map type. + +Expression* +Channel_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + source_location bloc = BUILTINS_LOCATION; + + Type* ctdt = Channel_type::make_chan_type_descriptor_type(); + + const Struct_field_list* fields = ctdt->struct_type()->fields(); + + Expression_list* vals = new Expression_list(); + vals->reserve(3); + + Struct_field_list::const_iterator p = fields->begin(); + gcc_assert(p->field_name() == "commonType"); + vals->push_back(this->type_descriptor_constructor(gogo, + RUNTIME_TYPE_KIND_CHAN, + name, NULL, true)); + + ++p; + gcc_assert(p->field_name() == "elem"); + vals->push_back(Expression::make_type_descriptor(this->element_type_, bloc)); + + ++p; + gcc_assert(p->field_name() == "dir"); + // These bits must match the ones in libgo/runtime/go-type.h. + int val = 0; + if (this->may_receive_) + val |= 1; + if (this->may_send_) + val |= 2; + mpz_t iv; + mpz_init_set_ui(iv, val); + vals->push_back(Expression::make_integer(&iv, p->type(), bloc)); + mpz_clear(iv); + + ++p; + gcc_assert(p == fields->end()); + + return Expression::make_struct_composite_literal(ctdt, vals, bloc); +} + +// Reflection string. + +void +Channel_type::do_reflection(Gogo* gogo, std::string* ret) const +{ + if (!this->may_send_) + ret->append("<-"); + ret->append("chan"); + if (!this->may_receive_) + ret->append("<-"); + ret->push_back(' '); + this->append_reflection(this->element_type_, gogo, ret); +} + +// Mangled name. + +void +Channel_type::do_mangled_name(Gogo* gogo, std::string* ret) const +{ + ret->push_back('C'); + this->append_mangled_name(this->element_type_, gogo, ret); + if (this->may_send_) + ret->push_back('s'); + if (this->may_receive_) + ret->push_back('r'); + ret->push_back('e'); +} + +// Export. + +void +Channel_type::do_export(Export* exp) const +{ + exp->write_c_string("chan "); + if (this->may_send_ && !this->may_receive_) + exp->write_c_string("-< "); + else if (this->may_receive_ && !this->may_send_) + exp->write_c_string("<- "); + exp->write_type(this->element_type_); +} + +// Import. + +Channel_type* +Channel_type::do_import(Import* imp) +{ + imp->require_c_string("chan "); + + bool may_send; + bool may_receive; + if (imp->match_c_string("-< ")) + { + imp->advance(3); + may_send = true; + may_receive = false; + } + else if (imp->match_c_string("<- ")) + { + imp->advance(3); + may_receive = true; + may_send = false; + } + else + { + may_send = true; + may_receive = true; + } + + Type* element_type = imp->read_type(); + + return Type::make_channel_type(may_send, may_receive, element_type); +} + +// Make a new channel type. + +Channel_type* +Type::make_channel_type(bool send, bool receive, Type* element_type) +{ + return new Channel_type(send, receive, element_type); +} + +// Class Interface_type. + +// Traversal. + +int +Interface_type::do_traverse(Traverse* traverse) +{ + if (this->methods_ == NULL) + return TRAVERSE_CONTINUE; + return this->methods_->traverse(traverse); +} + +// Finalize the methods. This handles interface inheritance. + +void +Interface_type::finalize_methods() +{ + if (this->methods_ == NULL) + return; + std::vector<Named_type*> seen; + bool is_recursive = false; + size_t from = 0; + size_t to = 0; + while (from < this->methods_->size()) + { + const Typed_identifier* p = &this->methods_->at(from); + if (!p->name().empty()) + { + size_t i; + for (i = 0; i < to; ++i) + { + if (this->methods_->at(i).name() == p->name()) + { + error_at(p->location(), "duplicate method %qs", + Gogo::message_name(p->name()).c_str()); + break; + } + } + if (i == to) + { + if (from != to) + this->methods_->set(to, *p); + ++to; + } + ++from; + continue; + } + + Interface_type* it = p->type()->interface_type(); + if (it == NULL) + { + error_at(p->location(), "interface contains embedded non-interface"); + ++from; + continue; + } + if (it == this) + { + if (!is_recursive) + { + error_at(p->location(), "invalid recursive interface"); + is_recursive = true; + } + ++from; + continue; + } + + Named_type* nt = p->type()->named_type(); + if (nt != NULL) + { + std::vector<Named_type*>::const_iterator q; + for (q = seen.begin(); q != seen.end(); ++q) + { + if (*q == nt) + { + error_at(p->location(), "inherited interface loop"); + break; + } + } + if (q != seen.end()) + { + ++from; + continue; + } + seen.push_back(nt); + } + + const Typed_identifier_list* methods = it->methods(); + if (methods == NULL) + { + ++from; + continue; + } + for (Typed_identifier_list::const_iterator q = methods->begin(); + q != methods->end(); + ++q) + { + if (q->name().empty()) + { + if (q->type()->forwarded() == p->type()->forwarded()) + error_at(p->location(), "interface inheritance loop"); + else + { + size_t i; + for (i = from + 1; i < this->methods_->size(); ++i) + { + const Typed_identifier* r = &this->methods_->at(i); + if (r->name().empty() + && r->type()->forwarded() == q->type()->forwarded()) + { + error_at(p->location(), + "inherited interface listed twice"); + break; + } + } + if (i == this->methods_->size()) + this->methods_->push_back(Typed_identifier(q->name(), + q->type(), + p->location())); + } + } + else if (this->find_method(q->name()) == NULL) + this->methods_->push_back(Typed_identifier(q->name(), q->type(), + p->location())); + else + { + if (!is_recursive) + error_at(p->location(), "inherited method %qs is ambiguous", + Gogo::message_name(q->name()).c_str()); + } + } + ++from; + } + if (to == 0) + { + delete this->methods_; + this->methods_ = NULL; + } + else + { + this->methods_->resize(to); + this->methods_->sort_by_name(); + } +} + +// Return the method NAME, or NULL. + +const Typed_identifier* +Interface_type::find_method(const std::string& name) const +{ + if (this->methods_ == NULL) + return NULL; + for (Typed_identifier_list::const_iterator p = this->methods_->begin(); + p != this->methods_->end(); + ++p) + if (p->name() == name) + return &*p; + return NULL; +} + +// Return the method index. + +size_t +Interface_type::method_index(const std::string& name) const +{ + gcc_assert(this->methods_ != NULL); + size_t ret = 0; + for (Typed_identifier_list::const_iterator p = this->methods_->begin(); + p != this->methods_->end(); + ++p, ++ret) + if (p->name() == name) + return ret; + gcc_unreachable(); +} + +// Return whether NAME is an unexported method, for better error +// reporting. + +bool +Interface_type::is_unexported_method(Gogo* gogo, const std::string& name) const +{ + if (this->methods_ == NULL) + return false; + for (Typed_identifier_list::const_iterator p = this->methods_->begin(); + p != this->methods_->end(); + ++p) + { + const std::string& method_name(p->name()); + if (Gogo::is_hidden_name(method_name) + && name == Gogo::unpack_hidden_name(method_name) + && gogo->pack_hidden_name(name, false) != method_name) + return true; + } + return false; +} + +// Whether this type is identical with T. + +bool +Interface_type::is_identical(const Interface_type* t, + bool errors_are_identical) const +{ + // We require the same methods with the same types. The methods + // have already been sorted. + if (this->methods() == NULL || t->methods() == NULL) + return this->methods() == t->methods(); + + Typed_identifier_list::const_iterator p1 = this->methods()->begin(); + for (Typed_identifier_list::const_iterator p2 = t->methods()->begin(); + p2 != t->methods()->end(); + ++p1, ++p2) + { + if (p1 == this->methods()->end()) + return false; + if (p1->name() != p2->name() + || !Type::are_identical(p1->type(), p2->type(), + errors_are_identical, NULL)) + return false; + } + if (p1 != this->methods()->end()) + return false; + return true; +} + +// Whether we can assign the interface type T to this type. The types +// are known to not be identical. An interface assignment is only +// permitted if T is known to implement all methods in THIS. +// Otherwise a type guard is required. + +bool +Interface_type::is_compatible_for_assign(const Interface_type* t, + std::string* reason) const +{ + if (this->methods() == NULL) + return true; + for (Typed_identifier_list::const_iterator p = this->methods()->begin(); + p != this->methods()->end(); + ++p) + { + const Typed_identifier* m = t->find_method(p->name()); + if (m == NULL) + { + if (reason != NULL) + { + char buf[200]; + snprintf(buf, sizeof buf, + _("need explicit conversion; missing method %s%s%s"), + open_quote, Gogo::message_name(p->name()).c_str(), + close_quote); + reason->assign(buf); + } + return false; + } + + std::string subreason; + if (!Type::are_identical(p->type(), m->type(), true, &subreason)) + { + if (reason != NULL) + { + std::string n = Gogo::message_name(p->name()); + size_t len = 100 + n.length() + subreason.length(); + char* buf = new char[len]; + if (subreason.empty()) + snprintf(buf, len, _("incompatible type for method %s%s%s"), + open_quote, n.c_str(), close_quote); + else + snprintf(buf, len, + _("incompatible type for method %s%s%s (%s)"), + open_quote, n.c_str(), close_quote, + subreason.c_str()); + reason->assign(buf); + delete[] buf; + } + return false; + } + } + + return true; +} + +// Hash code. + +unsigned int +Interface_type::do_hash_for_method(Gogo* gogo) const +{ + unsigned int ret = 0; + if (this->methods_ != NULL) + { + for (Typed_identifier_list::const_iterator p = this->methods_->begin(); + p != this->methods_->end(); + ++p) + { + ret = Type::hash_string(p->name(), ret); + ret += p->type()->hash_for_method(gogo); + ret <<= 1; + } + } + return ret; +} + +// Return true if T implements the interface. If it does not, and +// REASON is not NULL, set *REASON to a useful error message. + +bool +Interface_type::implements_interface(const Type* t, std::string* reason) const +{ + if (this->methods_ == NULL) + return true; + + bool is_pointer = false; + const Named_type* nt = t->named_type(); + const Struct_type* st = t->struct_type(); + // If we start with a named type, we don't dereference it to find + // methods. + if (nt == NULL) + { + const Type* pt = t->points_to(); + if (pt != NULL) + { + // If T is a pointer to a named type, then we need to look at + // the type to which it points. + is_pointer = true; + nt = pt->named_type(); + st = pt->struct_type(); + } + } + + // If we have a named type, get the methods from it rather than from + // any struct type. + if (nt != NULL) + st = NULL; + + // Only named and struct types have methods. + if (nt == NULL && st == NULL) + { + if (reason != NULL) + { + if (t->points_to() != NULL + && t->points_to()->interface_type() != NULL) + reason->assign(_("pointer to interface type has no methods")); + else + reason->assign(_("type has no methods")); + } + return false; + } + + if (nt != NULL ? !nt->has_any_methods() : !st->has_any_methods()) + { + if (reason != NULL) + { + if (t->points_to() != NULL + && t->points_to()->interface_type() != NULL) + reason->assign(_("pointer to interface type has no methods")); + else + reason->assign(_("type has no methods")); + } + return false; + } + + for (Typed_identifier_list::const_iterator p = this->methods_->begin(); + p != this->methods_->end(); + ++p) + { + bool is_ambiguous = false; + Method* m = (nt != NULL + ? nt->method_function(p->name(), &is_ambiguous) + : st->method_function(p->name(), &is_ambiguous)); + if (m == NULL) + { + if (reason != NULL) + { + std::string n = Gogo::message_name(p->name()); + size_t len = n.length() + 100; + char* buf = new char[len]; + if (is_ambiguous) + snprintf(buf, len, _("ambiguous method %s%s%s"), + open_quote, n.c_str(), close_quote); + else + snprintf(buf, len, _("missing method %s%s%s"), + open_quote, n.c_str(), close_quote); + reason->assign(buf); + delete[] buf; + } + return false; + } + + Function_type *p_fn_type = p->type()->function_type(); + Function_type* m_fn_type = m->type()->function_type(); + gcc_assert(p_fn_type != NULL && m_fn_type != NULL); + std::string subreason; + if (!p_fn_type->is_identical(m_fn_type, true, true, &subreason)) + { + if (reason != NULL) + { + std::string n = Gogo::message_name(p->name()); + size_t len = 100 + n.length() + subreason.length(); + char* buf = new char[len]; + if (subreason.empty()) + snprintf(buf, len, _("incompatible type for method %s%s%s"), + open_quote, n.c_str(), close_quote); + else + snprintf(buf, len, + _("incompatible type for method %s%s%s (%s)"), + open_quote, n.c_str(), close_quote, + subreason.c_str()); + reason->assign(buf); + delete[] buf; + } + return false; + } + + if (!is_pointer && !m->is_value_method()) + { + if (reason != NULL) + { + std::string n = Gogo::message_name(p->name()); + size_t len = 100 + n.length(); + char* buf = new char[len]; + snprintf(buf, len, _("method %s%s%s requires a pointer"), + open_quote, n.c_str(), close_quote); + reason->assign(buf); + delete[] buf; + } + return false; + } + } + + return true; +} + +// Return a tree for an interface type. An interface is a pointer to +// a struct. The struct has three fields. The first field is a +// pointer to the type descriptor for the dynamic type of the object. +// The second field is a pointer to a table of methods for the +// interface to be used with the object. The third field is the value +// of the object itself. + +tree +Interface_type::do_get_tree(Gogo* gogo) +{ + if (this->methods_ == NULL) + return Interface_type::empty_type_tree(gogo); + else + { + tree t = Interface_type::non_empty_type_tree(this->location_); + return this->fill_in_tree(gogo, t); + } +} + +// Return a singleton struct for an empty interface type. We use the +// same type for all empty interfaces. This lets us assign them to +// each other directly without triggering GIMPLE type errors. + +tree +Interface_type::empty_type_tree(Gogo* gogo) +{ + static tree empty_interface; + if (empty_interface != NULL_TREE) + return empty_interface; + + tree dtype = Type::make_type_descriptor_type()->get_tree(gogo); + dtype = build_pointer_type(build_qualified_type(dtype, TYPE_QUAL_CONST)); + return Gogo::builtin_struct(&empty_interface, "__go_empty_interface", + NULL_TREE, 2, + "__type_descriptor", + dtype, + "__object", + ptr_type_node); +} + +// Return a new struct for a non-empty interface type. The correct +// values are filled in by fill_in_tree. + +tree +Interface_type::non_empty_type_tree(source_location location) +{ + tree ret = make_node(RECORD_TYPE); + + tree field_trees = NULL_TREE; + tree* pp = &field_trees; + + tree name_tree = get_identifier("__methods"); + tree field = build_decl(location, FIELD_DECL, name_tree, ptr_type_node); + DECL_CONTEXT(field) = ret; + *pp = field; + pp = &DECL_CHAIN(field); + + name_tree = get_identifier("__object"); + field = build_decl(location, FIELD_DECL, name_tree, ptr_type_node); + DECL_CONTEXT(field) = ret; + *pp = field; + + TYPE_FIELDS(ret) = field_trees; + + layout_type(ret); + + return ret; +} + +// Fill in the tree for an interface type. This is used for named +// interface types. + +tree +Interface_type::fill_in_tree(Gogo* gogo, tree type) +{ + gcc_assert(this->methods_ != NULL); + + // Build the type of the table of methods. + + tree method_table = make_node(RECORD_TYPE); + + // The first field is a pointer to the type descriptor. + tree name_tree = get_identifier("__type_descriptor"); + tree dtype = Type::make_type_descriptor_type()->get_tree(gogo); + dtype = build_pointer_type(build_qualified_type(dtype, TYPE_QUAL_CONST)); + tree field = build_decl(this->location_, FIELD_DECL, name_tree, dtype); + DECL_CONTEXT(field) = method_table; + TYPE_FIELDS(method_table) = field; + + std::string last_name = ""; + tree* pp = &DECL_CHAIN(field); + for (Typed_identifier_list::const_iterator p = this->methods_->begin(); + p != this->methods_->end(); + ++p) + { + std::string name = Gogo::unpack_hidden_name(p->name()); + name_tree = get_identifier_with_length(name.data(), name.length()); + tree field_type = p->type()->get_tree(gogo); + if (field_type == error_mark_node) + return error_mark_node; + field = build_decl(this->location_, FIELD_DECL, name_tree, field_type); + DECL_CONTEXT(field) = method_table; + *pp = field; + pp = &DECL_CHAIN(field); + // Sanity check: the names should be sorted. + gcc_assert(p->name() > last_name); + last_name = p->name(); + } + layout_type(method_table); + + // Update the type of the __methods field from a generic pointer to + // a pointer to the method table. + field = TYPE_FIELDS(type); + gcc_assert(strcmp(IDENTIFIER_POINTER(DECL_NAME(field)), "__methods") == 0); + + TREE_TYPE(field) = build_pointer_type(method_table); + + return type; +} + +// Initialization value. + +tree +Interface_type::do_get_init_tree(Gogo*, tree type_tree, bool is_clear) +{ + if (is_clear) + return NULL; + + VEC(constructor_elt,gc)* init = VEC_alloc(constructor_elt, gc, 2); + for (tree field = TYPE_FIELDS(type_tree); + field != NULL_TREE; + field = DECL_CHAIN(field)) + { + constructor_elt* elt = VEC_quick_push(constructor_elt, init, NULL); + elt->index = field; + elt->value = fold_convert(TREE_TYPE(field), null_pointer_node); + } + + tree ret = build_constructor(type_tree, init); + TREE_CONSTANT(ret) = 1; + return ret; +} + +// The type of an interface type descriptor. + +Type* +Interface_type::make_interface_type_descriptor_type() +{ + static Type* ret; + if (ret == NULL) + { + Type* tdt = Type::make_type_descriptor_type(); + Type* ptdt = Type::make_type_descriptor_ptr_type(); + + Type* string_type = Type::lookup_string_type(); + Type* pointer_string_type = Type::make_pointer_type(string_type); + + Struct_type* sm = + Type::make_builtin_struct_type(3, + "name", pointer_string_type, + "pkgPath", pointer_string_type, + "typ", ptdt); + + Type* nsm = Type::make_builtin_named_type("imethod", sm); + + Type* slice_nsm = Type::make_array_type(nsm, NULL); + + Struct_type* s = Type::make_builtin_struct_type(2, + "", tdt, + "methods", slice_nsm); + + ret = Type::make_builtin_named_type("InterfaceType", s); + } + + return ret; +} + +// Build a type descriptor for an interface type. + +Expression* +Interface_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + source_location bloc = BUILTINS_LOCATION; + + Type* itdt = Interface_type::make_interface_type_descriptor_type(); + + const Struct_field_list* ifields = itdt->struct_type()->fields(); + + Expression_list* ivals = new Expression_list(); + ivals->reserve(2); + + Struct_field_list::const_iterator pif = ifields->begin(); + gcc_assert(pif->field_name() == "commonType"); + ivals->push_back(this->type_descriptor_constructor(gogo, + RUNTIME_TYPE_KIND_INTERFACE, + name, NULL, true)); + + ++pif; + gcc_assert(pif->field_name() == "methods"); + + Expression_list* methods = new Expression_list(); + if (this->methods_ != NULL && !this->methods_->empty()) + { + Type* elemtype = pif->type()->array_type()->element_type(); + + methods->reserve(this->methods_->size()); + for (Typed_identifier_list::const_iterator pm = this->methods_->begin(); + pm != this->methods_->end(); + ++pm) + { + const Struct_field_list* mfields = elemtype->struct_type()->fields(); + + Expression_list* mvals = new Expression_list(); + mvals->reserve(3); + + Struct_field_list::const_iterator pmf = mfields->begin(); + gcc_assert(pmf->field_name() == "name"); + std::string s = Gogo::unpack_hidden_name(pm->name()); + Expression* e = Expression::make_string(s, bloc); + mvals->push_back(Expression::make_unary(OPERATOR_AND, e, bloc)); + + ++pmf; + gcc_assert(pmf->field_name() == "pkgPath"); + if (!Gogo::is_hidden_name(pm->name())) + mvals->push_back(Expression::make_nil(bloc)); + else + { + s = Gogo::hidden_name_prefix(pm->name()); + e = Expression::make_string(s, bloc); + mvals->push_back(Expression::make_unary(OPERATOR_AND, e, bloc)); + } + + ++pmf; + gcc_assert(pmf->field_name() == "typ"); + mvals->push_back(Expression::make_type_descriptor(pm->type(), bloc)); + + ++pmf; + gcc_assert(pmf == mfields->end()); + + e = Expression::make_struct_composite_literal(elemtype, mvals, + bloc); + methods->push_back(e); + } + } + + ivals->push_back(Expression::make_slice_composite_literal(pif->type(), + methods, bloc)); + + ++pif; + gcc_assert(pif == ifields->end()); + + return Expression::make_struct_composite_literal(itdt, ivals, bloc); +} + +// Reflection string. + +void +Interface_type::do_reflection(Gogo* gogo, std::string* ret) const +{ + ret->append("interface {"); + if (this->methods_ != NULL) + { + for (Typed_identifier_list::const_iterator p = this->methods_->begin(); + p != this->methods_->end(); + ++p) + { + if (p != this->methods_->begin()) + ret->append(";"); + ret->push_back(' '); + ret->append(Gogo::unpack_hidden_name(p->name())); + std::string sub = p->type()->reflection(gogo); + gcc_assert(sub.compare(0, 4, "func") == 0); + sub = sub.substr(4); + ret->append(sub); + } + } + ret->append(" }"); +} + +// Mangled name. + +void +Interface_type::do_mangled_name(Gogo* gogo, std::string* ret) const +{ + ret->push_back('I'); + + const Typed_identifier_list* methods = this->methods_; + if (methods != NULL) + { + for (Typed_identifier_list::const_iterator p = methods->begin(); + p != methods->end(); + ++p) + { + std::string n = Gogo::unpack_hidden_name(p->name()); + char buf[20]; + snprintf(buf, sizeof buf, "%u_", + static_cast<unsigned int>(n.length())); + ret->append(buf); + ret->append(n); + this->append_mangled_name(p->type(), gogo, ret); + } + } + + ret->push_back('e'); +} + +// Export. + +void +Interface_type::do_export(Export* exp) const +{ + exp->write_c_string("interface { "); + + const Typed_identifier_list* methods = this->methods_; + if (methods != NULL) + { + for (Typed_identifier_list::const_iterator pm = methods->begin(); + pm != methods->end(); + ++pm) + { + exp->write_string(pm->name()); + exp->write_c_string(" ("); + + const Function_type* fntype = pm->type()->function_type(); + + bool first = true; + const Typed_identifier_list* parameters = fntype->parameters(); + if (parameters != NULL) + { + bool is_varargs = fntype->is_varargs(); + for (Typed_identifier_list::const_iterator pp = + parameters->begin(); + pp != parameters->end(); + ++pp) + { + if (first) + first = false; + else + exp->write_c_string(", "); + if (!is_varargs || pp + 1 != parameters->end()) + exp->write_type(pp->type()); + else + { + exp->write_c_string("..."); + Type *pptype = pp->type(); + exp->write_type(pptype->array_type()->element_type()); + } + } + } + + exp->write_c_string(")"); + + const Typed_identifier_list* results = fntype->results(); + if (results != NULL) + { + exp->write_c_string(" "); + if (results->size() == 1) + exp->write_type(results->begin()->type()); + else + { + first = true; + exp->write_c_string("("); + for (Typed_identifier_list::const_iterator p = + results->begin(); + p != results->end(); + ++p) + { + if (first) + first = false; + else + exp->write_c_string(", "); + exp->write_type(p->type()); + } + exp->write_c_string(")"); + } + } + + exp->write_c_string("; "); + } + } + + exp->write_c_string("}"); +} + +// Import an interface type. + +Interface_type* +Interface_type::do_import(Import* imp) +{ + imp->require_c_string("interface { "); + + Typed_identifier_list* methods = new Typed_identifier_list; + while (imp->peek_char() != '}') + { + std::string name = imp->read_identifier(); + imp->require_c_string(" ("); + + Typed_identifier_list* parameters; + bool is_varargs = false; + if (imp->peek_char() == ')') + parameters = NULL; + else + { + parameters = new Typed_identifier_list; + while (true) + { + if (imp->match_c_string("...")) + { + imp->advance(3); + is_varargs = true; + } + + Type* ptype = imp->read_type(); + if (is_varargs) + ptype = Type::make_array_type(ptype, NULL); + parameters->push_back(Typed_identifier(Import::import_marker, + ptype, imp->location())); + if (imp->peek_char() != ',') + break; + gcc_assert(!is_varargs); + imp->require_c_string(", "); + } + } + imp->require_c_string(")"); + + Typed_identifier_list* results; + if (imp->peek_char() != ' ') + results = NULL; + else + { + results = new Typed_identifier_list; + imp->advance(1); + if (imp->peek_char() != '(') + { + Type* rtype = imp->read_type(); + results->push_back(Typed_identifier(Import::import_marker, + rtype, imp->location())); + } + else + { + imp->advance(1); + while (true) + { + Type* rtype = imp->read_type(); + results->push_back(Typed_identifier(Import::import_marker, + rtype, imp->location())); + if (imp->peek_char() != ',') + break; + imp->require_c_string(", "); + } + imp->require_c_string(")"); + } + } + + Function_type* fntype = Type::make_function_type(NULL, parameters, + results, + imp->location()); + if (is_varargs) + fntype->set_is_varargs(); + methods->push_back(Typed_identifier(name, fntype, imp->location())); + + imp->require_c_string("; "); + } + + imp->require_c_string("}"); + + if (methods->empty()) + { + delete methods; + methods = NULL; + } + + return Type::make_interface_type(methods, imp->location()); +} + +// Make an interface type. + +Interface_type* +Type::make_interface_type(Typed_identifier_list* methods, + source_location location) +{ + return new Interface_type(methods, location); +} + +// Class Method. + +// Bind a method to an object. + +Expression* +Method::bind_method(Expression* expr, source_location location) const +{ + if (this->stub_ == NULL) + { + // When there is no stub object, the binding is determined by + // the child class. + return this->do_bind_method(expr, location); + } + + Expression* func = Expression::make_func_reference(this->stub_, NULL, + location); + return Expression::make_bound_method(expr, func, location); +} + +// Return the named object associated with a method. This may only be +// called after methods are finalized. + +Named_object* +Method::named_object() const +{ + if (this->stub_ != NULL) + return this->stub_; + return this->do_named_object(); +} + +// Class Named_method. + +// The type of the method. + +Function_type* +Named_method::do_type() const +{ + if (this->named_object_->is_function()) + return this->named_object_->func_value()->type(); + else if (this->named_object_->is_function_declaration()) + return this->named_object_->func_declaration_value()->type(); + else + gcc_unreachable(); +} + +// Return the location of the method receiver. + +source_location +Named_method::do_receiver_location() const +{ + return this->do_type()->receiver()->location(); +} + +// Bind a method to an object. + +Expression* +Named_method::do_bind_method(Expression* expr, source_location location) const +{ + Expression* func = Expression::make_func_reference(this->named_object_, NULL, + location); + Bound_method_expression* bme = Expression::make_bound_method(expr, func, + location); + // If this is not a local method, and it does not use a stub, then + // the real method expects a different type. We need to cast the + // first argument. + if (this->depth() > 0 && !this->needs_stub_method()) + { + Function_type* ftype = this->do_type(); + gcc_assert(ftype->is_method()); + Type* frtype = ftype->receiver()->type(); + bme->set_first_argument_type(frtype); + } + return bme; +} + +// Class Interface_method. + +// Bind a method to an object. + +Expression* +Interface_method::do_bind_method(Expression* expr, + source_location location) const +{ + return Expression::make_interface_field_reference(expr, this->name_, + location); +} + +// Class Methods. + +// Insert a new method. Return true if it was inserted, false +// otherwise. + +bool +Methods::insert(const std::string& name, Method* m) +{ + std::pair<Method_map::iterator, bool> ins = + this->methods_.insert(std::make_pair(name, m)); + if (ins.second) + return true; + else + { + Method* old_method = ins.first->second; + if (m->depth() < old_method->depth()) + { + delete old_method; + ins.first->second = m; + return true; + } + else + { + if (m->depth() == old_method->depth()) + old_method->set_is_ambiguous(); + return false; + } + } +} + +// Return the number of unambiguous methods. + +size_t +Methods::count() const +{ + size_t ret = 0; + for (Method_map::const_iterator p = this->methods_.begin(); + p != this->methods_.end(); + ++p) + if (!p->second->is_ambiguous()) + ++ret; + return ret; +} + +// Class Named_type. + +// Return the name of the type. + +const std::string& +Named_type::name() const +{ + return this->named_object_->name(); +} + +// Return the name of the type to use in an error message. + +std::string +Named_type::message_name() const +{ + return this->named_object_->message_name(); +} + +// Return the base type for this type. We have to be careful about +// circular type definitions, which are invalid but may be seen here. + +Type* +Named_type::named_base() +{ + if (this->seen_ > 0) + return this; + ++this->seen_; + Type* ret = this->type_->base(); + --this->seen_; + return ret; +} + +const Type* +Named_type::named_base() const +{ + if (this->seen_ > 0) + return this; + ++this->seen_; + const Type* ret = this->type_->base(); + --this->seen_; + return ret; +} + +// Return whether this is an error type. We have to be careful about +// circular type definitions, which are invalid but may be seen here. + +bool +Named_type::is_named_error_type() const +{ + if (this->seen_ > 0) + return false; + ++this->seen_; + bool ret = this->type_->is_error_type(); + --this->seen_; + return ret; +} + +// Add a method to this type. + +Named_object* +Named_type::add_method(const std::string& name, Function* function) +{ + if (this->local_methods_ == NULL) + this->local_methods_ = new Bindings(NULL); + return this->local_methods_->add_function(name, NULL, function); +} + +// Add a method declaration to this type. + +Named_object* +Named_type::add_method_declaration(const std::string& name, Package* package, + Function_type* type, + source_location location) +{ + if (this->local_methods_ == NULL) + this->local_methods_ = new Bindings(NULL); + return this->local_methods_->add_function_declaration(name, package, type, + location); +} + +// Add an existing method to this type. + +void +Named_type::add_existing_method(Named_object* no) +{ + if (this->local_methods_ == NULL) + this->local_methods_ = new Bindings(NULL); + this->local_methods_->add_named_object(no); +} + +// Look for a local method NAME, and returns its named object, or NULL +// if not there. + +Named_object* +Named_type::find_local_method(const std::string& name) const +{ + if (this->local_methods_ == NULL) + return NULL; + return this->local_methods_->lookup(name); +} + +// Return whether NAME is an unexported field or method, for better +// error reporting. + +bool +Named_type::is_unexported_local_method(Gogo* gogo, + const std::string& name) const +{ + Bindings* methods = this->local_methods_; + if (methods != NULL) + { + for (Bindings::const_declarations_iterator p = + methods->begin_declarations(); + p != methods->end_declarations(); + ++p) + { + if (Gogo::is_hidden_name(p->first) + && name == Gogo::unpack_hidden_name(p->first) + && gogo->pack_hidden_name(name, false) != p->first) + return true; + } + } + return false; +} + +// Build the complete list of methods for this type, which means +// recursively including all methods for anonymous fields. Create all +// stub methods. + +void +Named_type::finalize_methods(Gogo* gogo) +{ + if (this->all_methods_ != NULL) + return; + + if (this->local_methods_ != NULL + && (this->points_to() != NULL || this->interface_type() != NULL)) + { + const Bindings* lm = this->local_methods_; + for (Bindings::const_declarations_iterator p = lm->begin_declarations(); + p != lm->end_declarations(); + ++p) + error_at(p->second->location(), + "invalid pointer or interface receiver type"); + delete this->local_methods_; + this->local_methods_ = NULL; + return; + } + + Type::finalize_methods(gogo, this, this->location_, &this->all_methods_); +} + +// Return the method NAME, or NULL if there isn't one or if it is +// ambiguous. Set *IS_AMBIGUOUS if the method exists but is +// ambiguous. + +Method* +Named_type::method_function(const std::string& name, bool* is_ambiguous) const +{ + return Type::method_function(this->all_methods_, name, is_ambiguous); +} + +// Return a pointer to the interface method table for this type for +// the interface INTERFACE. IS_POINTER is true if this is for a +// pointer to THIS. + +tree +Named_type::interface_method_table(Gogo* gogo, const Interface_type* interface, + bool is_pointer) +{ + gcc_assert(!interface->is_empty()); + + Interface_method_tables** pimt = (is_pointer + ? &this->interface_method_tables_ + : &this->pointer_interface_method_tables_); + + if (*pimt == NULL) + *pimt = new Interface_method_tables(5); + + std::pair<const Interface_type*, tree> val(interface, NULL_TREE); + std::pair<Interface_method_tables::iterator, bool> ins = (*pimt)->insert(val); + + if (ins.second) + { + // This is a new entry in the hash table. + gcc_assert(ins.first->second == NULL_TREE); + ins.first->second = gogo->interface_method_table_for_type(interface, + this, + is_pointer); + } + + tree decl = ins.first->second; + if (decl == error_mark_node) + return error_mark_node; + gcc_assert(decl != NULL_TREE && TREE_CODE(decl) == VAR_DECL); + return build_fold_addr_expr(decl); +} + +// Return whether a named type has any hidden fields. + +bool +Named_type::named_type_has_hidden_fields(std::string* reason) const +{ + if (this->seen_ > 0) + return false; + ++this->seen_; + bool ret = this->type_->has_hidden_fields(this, reason); + --this->seen_; + return ret; +} + +// Look for a use of a complete type within another type. This is +// used to check that we don't try to use a type within itself. + +class Find_type_use : public Traverse +{ + public: + Find_type_use(Named_type* find_type) + : Traverse(traverse_types), + find_type_(find_type), found_(false) + { } + + // Whether we found the type. + bool + found() const + { return this->found_; } + + protected: + int + type(Type*); + + private: + // The type we are looking for. + Named_type* find_type_; + // Whether we found the type. + bool found_; +}; + +// Check for FIND_TYPE in TYPE. + +int +Find_type_use::type(Type* type) +{ + if (type->named_type() != NULL && this->find_type_ == type->named_type()) + { + this->found_ = true; + return TRAVERSE_EXIT; + } + + // It's OK if we see a reference to the type in any type which is + // essentially a pointer: a pointer, a slice, a function, a map, or + // a channel. + if (type->points_to() != NULL + || type->is_open_array_type() + || type->function_type() != NULL + || type->map_type() != NULL + || type->channel_type() != NULL) + return TRAVERSE_SKIP_COMPONENTS; + + // For an interface, a reference to the type in a method type should + // be ignored, but we have to consider direct inheritance. When + // this is called, there may be cases of direct inheritance + // represented as a method with no name. + if (type->interface_type() != NULL) + { + const Typed_identifier_list* methods = type->interface_type()->methods(); + if (methods != NULL) + { + for (Typed_identifier_list::const_iterator p = methods->begin(); + p != methods->end(); + ++p) + { + if (p->name().empty()) + { + if (Type::traverse(p->type(), this) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + } + } + return TRAVERSE_SKIP_COMPONENTS; + } + + // Otherwise, FIND_TYPE_ depends on TYPE, in the sense that we need + // to convert TYPE to the backend representation before we convert + // FIND_TYPE_. + if (type->named_type() != NULL) + { + switch (type->base()->classification()) + { + case Type::TYPE_ERROR: + case Type::TYPE_BOOLEAN: + case Type::TYPE_INTEGER: + case Type::TYPE_FLOAT: + case Type::TYPE_COMPLEX: + case Type::TYPE_STRING: + case Type::TYPE_NIL: + break; + + case Type::TYPE_ARRAY: + case Type::TYPE_STRUCT: + this->find_type_->add_dependency(type->named_type()); + break; + + case Type::TYPE_VOID: + case Type::TYPE_SINK: + case Type::TYPE_FUNCTION: + case Type::TYPE_POINTER: + case Type::TYPE_CALL_MULTIPLE_RESULT: + case Type::TYPE_MAP: + case Type::TYPE_CHANNEL: + case Type::TYPE_INTERFACE: + case Type::TYPE_NAMED: + case Type::TYPE_FORWARD: + default: + gcc_unreachable(); + } + } + + return TRAVERSE_CONTINUE; +} + +// Verify that a named type does not refer to itself. + +bool +Named_type::do_verify() +{ + Find_type_use find(this); + Type::traverse(this->type_, &find); + if (find.found()) + { + error_at(this->location_, "invalid recursive type %qs", + this->message_name().c_str()); + this->is_error_ = true; + return false; + } + + // Check whether any of the local methods overloads an existing + // struct field or interface method. We don't need to check the + // list of methods against itself: that is handled by the Bindings + // code. + if (this->local_methods_ != NULL) + { + Struct_type* st = this->type_->struct_type(); + Interface_type* it = this->type_->interface_type(); + bool found_dup = false; + if (st != NULL || it != NULL) + { + for (Bindings::const_declarations_iterator p = + this->local_methods_->begin_declarations(); + p != this->local_methods_->end_declarations(); + ++p) + { + const std::string& name(p->first); + if (st != NULL && st->find_local_field(name, NULL) != NULL) + { + error_at(p->second->location(), + "method %qs redeclares struct field name", + Gogo::message_name(name).c_str()); + found_dup = true; + } + if (it != NULL && it->find_method(name) != NULL) + { + error_at(p->second->location(), + "method %qs redeclares interface method name", + Gogo::message_name(name).c_str()); + found_dup = true; + } + } + } + if (found_dup) + return false; + } + + return true; +} + +// Return whether this type is or contains a pointer. + +bool +Named_type::do_has_pointer() const +{ + if (this->seen_ > 0) + return false; + ++this->seen_; + bool ret = this->type_->has_pointer(); + --this->seen_; + return ret; +} + +// Return a hash code. This is used for method lookup. We simply +// hash on the name itself. + +unsigned int +Named_type::do_hash_for_method(Gogo* gogo) const +{ + const std::string& name(this->named_object()->name()); + unsigned int ret = Type::hash_string(name, 0); + + // GOGO will be NULL here when called from Type_hash_identical. + // That is OK because that is only used for internal hash tables + // where we are going to be comparing named types for equality. In + // other cases, which are cases where the runtime is going to + // compare hash codes to see if the types are the same, we need to + // include the package prefix and name in the hash. + if (gogo != NULL && !Gogo::is_hidden_name(name) && !this->is_builtin()) + { + const Package* package = this->named_object()->package(); + if (package == NULL) + { + ret = Type::hash_string(gogo->unique_prefix(), ret); + ret = Type::hash_string(gogo->package_name(), ret); + } + else + { + ret = Type::hash_string(package->unique_prefix(), ret); + ret = Type::hash_string(package->name(), ret); + } + } + + return ret; +} + +// Convert a named type to the backend representation. In order to +// get dependencies right, we fill in a dummy structure for this type, +// then convert all the dependencies, then complete this type. When +// this function is complete, the size of the type is known. + +void +Named_type::convert(Gogo* gogo) +{ + if (this->is_error_ || this->is_converted_) + return; + + this->create_placeholder(gogo); + + // Convert all the dependencies. If they refer indirectly back to + // this type, they will pick up the intermediate tree we just + // created. + for (std::vector<Named_type*>::const_iterator p = this->dependencies_.begin(); + p != this->dependencies_.end(); + ++p) + (*p)->convert(gogo); + + // Complete this type. + tree t = this->named_tree_; + Type* base = this->type_->base(); + switch (base->classification()) + { + case TYPE_VOID: + case TYPE_BOOLEAN: + case TYPE_INTEGER: + case TYPE_FLOAT: + case TYPE_COMPLEX: + case TYPE_STRING: + case TYPE_NIL: + break; + + case TYPE_MAP: + case TYPE_CHANNEL: + break; + + case TYPE_FUNCTION: + case TYPE_POINTER: + // The size of these types is already correct. + break; + + case TYPE_STRUCT: + t = base->struct_type()->fill_in_tree(gogo, t); + break; + + case TYPE_ARRAY: + if (!base->is_open_array_type()) + t = base->array_type()->fill_in_array_tree(gogo, t); + break; + + case TYPE_INTERFACE: + if (!base->interface_type()->is_empty()) + t = base->interface_type()->fill_in_tree(gogo, t); + break; + + case TYPE_ERROR: + return; + + default: + case TYPE_SINK: + case TYPE_CALL_MULTIPLE_RESULT: + case TYPE_NAMED: + case TYPE_FORWARD: + gcc_unreachable(); + } + + this->named_tree_ = t; + + if (t == error_mark_node) + this->is_error_ = true; + else + gcc_assert(TYPE_SIZE(t) != NULL_TREE); + + this->is_converted_ = true; +} + +// Create the placeholder for a named type. This is the first step in +// converting to the backend representation. + +void +Named_type::create_placeholder(Gogo* gogo) +{ + if (this->is_error_) + this->named_tree_ = error_mark_node; + + if (this->named_tree_ != NULL_TREE) + return; + + // Create the structure for this type. Note that because we call + // base() here, we don't attempt to represent a named type defined + // as another named type. Instead both named types will point to + // different base representations. + Type* base = this->type_->base(); + tree t; + switch (base->classification()) + { + case TYPE_ERROR: + this->is_error_ = true; + this->named_tree_ = error_mark_node; + return; + + case TYPE_VOID: + case TYPE_BOOLEAN: + case TYPE_INTEGER: + case TYPE_FLOAT: + case TYPE_COMPLEX: + case TYPE_STRING: + case TYPE_NIL: + // These are simple basic types, we can just create them + // directly. + t = Type::get_named_type_tree(gogo, base); + if (t == error_mark_node) + { + this->is_error_ = true; + this->named_tree_ = error_mark_node; + return; + } + t = build_variant_type_copy(t); + break; + + case TYPE_MAP: + case TYPE_CHANNEL: + // All maps and channels have the same type in GENERIC. + t = Type::get_named_type_tree(gogo, base); + if (t == error_mark_node) + { + this->is_error_ = true; + this->named_tree_ = error_mark_node; + return; + } + t = build_variant_type_copy(t); + break; + + case TYPE_FUNCTION: + case TYPE_POINTER: + t = build_variant_type_copy(ptr_type_node); + break; + + case TYPE_STRUCT: + t = make_node(RECORD_TYPE); + break; + + case TYPE_ARRAY: + if (base->is_open_array_type()) + t = gogo->slice_type_tree(void_type_node); + else + t = make_node(ARRAY_TYPE); + break; + + case TYPE_INTERFACE: + if (base->interface_type()->is_empty()) + { + t = Interface_type::empty_type_tree(gogo); + t = build_variant_type_copy(t); + } + else + { + source_location loc = base->interface_type()->location(); + t = Interface_type::non_empty_type_tree(loc); + } + break; + + default: + case TYPE_SINK: + case TYPE_CALL_MULTIPLE_RESULT: + case TYPE_NAMED: + case TYPE_FORWARD: + gcc_unreachable(); + } + + // Create the named type. + + tree id = this->named_object_->get_id(gogo); + tree decl = build_decl(this->location_, TYPE_DECL, id, t); + TYPE_NAME(t) = decl; + + this->named_tree_ = t; +} + +// Get a tree for a named type. + +tree +Named_type::do_get_tree(Gogo* gogo) +{ + if (this->is_error_) + return error_mark_node; + + tree t = this->named_tree_; + + // FIXME: GOGO can be NULL when called from go_type_for_size, which + // is only used for basic types. + if (gogo == NULL || !gogo->named_types_are_converted()) + { + // We have not completed converting named types. NAMED_TREE_ is + // a placeholder and we shouldn't do anything further. + if (t != NULL_TREE) + return t; + + // We don't build dependencies for types whose sizes do not + // change or are not relevant, so we may see them here while + // converting types. + this->create_placeholder(gogo); + t = this->named_tree_; + gcc_assert(t != NULL_TREE); + return t; + } + + // We are not converting types. This should only be called if the + // type has already been converted. + if (!this->is_converted_) + { + gcc_assert(saw_errors()); + return error_mark_node; + } + + gcc_assert(t != NULL_TREE && TYPE_SIZE(t) != NULL_TREE); + + // Complete the tree. + Type* base = this->type_->base(); + tree t1; + switch (base->classification()) + { + case TYPE_ERROR: + return error_mark_node; + + case TYPE_VOID: + case TYPE_BOOLEAN: + case TYPE_INTEGER: + case TYPE_FLOAT: + case TYPE_COMPLEX: + case TYPE_STRING: + case TYPE_NIL: + case TYPE_MAP: + case TYPE_CHANNEL: + case TYPE_STRUCT: + case TYPE_INTERFACE: + return t; + + case TYPE_FUNCTION: + // Don't build a circular data structure. GENERIC can't handle + // it. + if (this->seen_ > 0) + { + this->is_circular_ = true; + return ptr_type_node; + } + ++this->seen_; + t1 = Type::get_named_type_tree(gogo, base); + --this->seen_; + if (t1 == error_mark_node) + return error_mark_node; + if (this->is_circular_) + t1 = ptr_type_node; + gcc_assert(t != NULL_TREE && TREE_CODE(t) == POINTER_TYPE); + gcc_assert(TREE_CODE(t1) == POINTER_TYPE); + TREE_TYPE(t) = TREE_TYPE(t1); + return t; + + case TYPE_POINTER: + // Don't build a circular data structure. GENERIC can't handle + // it. + if (this->seen_ > 0) + { + this->is_circular_ = true; + return ptr_type_node; + } + ++this->seen_; + t1 = Type::get_named_type_tree(gogo, base); + --this->seen_; + if (t1 == error_mark_node) + return error_mark_node; + if (this->is_circular_) + t1 = ptr_type_node; + gcc_assert(t != NULL_TREE && TREE_CODE(t) == POINTER_TYPE); + gcc_assert(TREE_CODE(t1) == POINTER_TYPE); + TREE_TYPE(t) = TREE_TYPE(t1); + return t; + + case TYPE_ARRAY: + if (base->is_open_array_type()) + { + if (this->seen_ > 0) + return t; + else + { + ++this->seen_; + t = base->array_type()->fill_in_slice_tree(gogo, t); + --this->seen_; + } + } + return t; + + default: + case TYPE_SINK: + case TYPE_CALL_MULTIPLE_RESULT: + case TYPE_NAMED: + case TYPE_FORWARD: + gcc_unreachable(); + } + + gcc_unreachable(); +} + +// Build a type descriptor for a named type. + +Expression* +Named_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + // If NAME is not NULL, then we don't really want the type + // descriptor for this type; we want the descriptor for the + // underlying type, giving it the name NAME. + return this->named_type_descriptor(gogo, this->type_, + name == NULL ? this : name); +} + +// Add to the reflection string. This is used mostly for the name of +// the type used in a type descriptor, not for actual reflection +// strings. + +void +Named_type::do_reflection(Gogo* gogo, std::string* ret) const +{ + if (this->location() != BUILTINS_LOCATION) + { + const Package* package = this->named_object_->package(); + if (package != NULL) + ret->append(package->name()); + else + ret->append(gogo->package_name()); + ret->push_back('.'); + } + if (this->in_function_ != NULL) + { + ret->append(Gogo::unpack_hidden_name(this->in_function_->name())); + ret->push_back('$'); + } + ret->append(Gogo::unpack_hidden_name(this->named_object_->name())); +} + +// Get the mangled name. + +void +Named_type::do_mangled_name(Gogo* gogo, std::string* ret) const +{ + Named_object* no = this->named_object_; + std::string name; + if (this->location() == BUILTINS_LOCATION) + gcc_assert(this->in_function_ == NULL); + else + { + const std::string& unique_prefix(no->package() == NULL + ? gogo->unique_prefix() + : no->package()->unique_prefix()); + const std::string& package_name(no->package() == NULL + ? gogo->package_name() + : no->package()->name()); + name = unique_prefix; + name.append(1, '.'); + name.append(package_name); + name.append(1, '.'); + if (this->in_function_ != NULL) + { + name.append(Gogo::unpack_hidden_name(this->in_function_->name())); + name.append(1, '$'); + } + } + name.append(Gogo::unpack_hidden_name(no->name())); + char buf[20]; + snprintf(buf, sizeof buf, "N%u_", static_cast<unsigned int>(name.length())); + ret->append(buf); + ret->append(name); +} + +// Export the type. This is called to export a global type. + +void +Named_type::export_named_type(Export* exp, const std::string&) const +{ + // We don't need to write the name of the type here, because it will + // be written by Export::write_type anyhow. + exp->write_c_string("type "); + exp->write_type(this); + exp->write_c_string(";\n"); +} + +// Import a named type. + +void +Named_type::import_named_type(Import* imp, Named_type** ptype) +{ + imp->require_c_string("type "); + Type *type = imp->read_type(); + *ptype = type->named_type(); + gcc_assert(*ptype != NULL); + imp->require_c_string(";\n"); +} + +// Export the type when it is referenced by another type. In this +// case Export::export_type will already have issued the name. + +void +Named_type::do_export(Export* exp) const +{ + exp->write_type(this->type_); + + // To save space, we only export the methods directly attached to + // this type. + Bindings* methods = this->local_methods_; + if (methods == NULL) + return; + + exp->write_c_string("\n"); + for (Bindings::const_definitions_iterator p = methods->begin_definitions(); + p != methods->end_definitions(); + ++p) + { + exp->write_c_string(" "); + (*p)->export_named_object(exp); + } + + for (Bindings::const_declarations_iterator p = methods->begin_declarations(); + p != methods->end_declarations(); + ++p) + { + if (p->second->is_function_declaration()) + { + exp->write_c_string(" "); + p->second->export_named_object(exp); + } + } +} + +// Make a named type. + +Named_type* +Type::make_named_type(Named_object* named_object, Type* type, + source_location location) +{ + return new Named_type(named_object, type, location); +} + +// Finalize the methods for TYPE. It will be a named type or a struct +// type. This sets *ALL_METHODS to the list of methods, and builds +// all required stubs. + +void +Type::finalize_methods(Gogo* gogo, const Type* type, source_location location, + Methods** all_methods) +{ + *all_methods = NULL; + Types_seen types_seen; + Type::add_methods_for_type(type, NULL, 0, false, false, &types_seen, + all_methods); + Type::build_stub_methods(gogo, type, *all_methods, location); +} + +// Add the methods for TYPE to *METHODS. FIELD_INDEXES is used to +// build up the struct field indexes as we go. DEPTH is the depth of +// the field within TYPE. IS_EMBEDDED_POINTER is true if we are +// adding these methods for an anonymous field with pointer type. +// NEEDS_STUB_METHOD is true if we need to use a stub method which +// calls the real method. TYPES_SEEN is used to avoid infinite +// recursion. + +void +Type::add_methods_for_type(const Type* type, + const Method::Field_indexes* field_indexes, + unsigned int depth, + bool is_embedded_pointer, + bool needs_stub_method, + Types_seen* types_seen, + Methods** methods) +{ + // Pointer types may not have methods. + if (type->points_to() != NULL) + return; + + const Named_type* nt = type->named_type(); + if (nt != NULL) + { + std::pair<Types_seen::iterator, bool> ins = types_seen->insert(nt); + if (!ins.second) + return; + } + + if (nt != NULL) + Type::add_local_methods_for_type(nt, field_indexes, depth, + is_embedded_pointer, needs_stub_method, + methods); + + Type::add_embedded_methods_for_type(type, field_indexes, depth, + is_embedded_pointer, needs_stub_method, + types_seen, methods); + + // If we are called with depth > 0, then we are looking at an + // anonymous field of a struct. If such a field has interface type, + // then we need to add the interface methods. We don't want to add + // them when depth == 0, because we will already handle them + // following the usual rules for an interface type. + if (depth > 0) + Type::add_interface_methods_for_type(type, field_indexes, depth, methods); +} + +// Add the local methods for the named type NT to *METHODS. The +// parameters are as for add_methods_to_type. + +void +Type::add_local_methods_for_type(const Named_type* nt, + const Method::Field_indexes* field_indexes, + unsigned int depth, + bool is_embedded_pointer, + bool needs_stub_method, + Methods** methods) +{ + const Bindings* local_methods = nt->local_methods(); + if (local_methods == NULL) + return; + + if (*methods == NULL) + *methods = new Methods(); + + for (Bindings::const_declarations_iterator p = + local_methods->begin_declarations(); + p != local_methods->end_declarations(); + ++p) + { + Named_object* no = p->second; + bool is_value_method = (is_embedded_pointer + || !Type::method_expects_pointer(no)); + Method* m = new Named_method(no, field_indexes, depth, is_value_method, + (needs_stub_method + || (depth > 0 && is_value_method))); + if (!(*methods)->insert(no->name(), m)) + delete m; + } +} + +// Add the embedded methods for TYPE to *METHODS. These are the +// methods attached to anonymous fields. The parameters are as for +// add_methods_to_type. + +void +Type::add_embedded_methods_for_type(const Type* type, + const Method::Field_indexes* field_indexes, + unsigned int depth, + bool is_embedded_pointer, + bool needs_stub_method, + Types_seen* types_seen, + Methods** methods) +{ + // Look for anonymous fields in TYPE. TYPE has fields if it is a + // struct. + const Struct_type* st = type->struct_type(); + if (st == NULL) + return; + + const Struct_field_list* fields = st->fields(); + if (fields == NULL) + return; + + unsigned int i = 0; + for (Struct_field_list::const_iterator pf = fields->begin(); + pf != fields->end(); + ++pf, ++i) + { + if (!pf->is_anonymous()) + continue; + + Type* ftype = pf->type(); + bool is_pointer = false; + if (ftype->points_to() != NULL) + { + ftype = ftype->points_to(); + is_pointer = true; + } + Named_type* fnt = ftype->named_type(); + if (fnt == NULL) + { + // This is an error, but it will be diagnosed elsewhere. + continue; + } + + Method::Field_indexes* sub_field_indexes = new Method::Field_indexes(); + sub_field_indexes->next = field_indexes; + sub_field_indexes->field_index = i; + + Type::add_methods_for_type(fnt, sub_field_indexes, depth + 1, + (is_embedded_pointer || is_pointer), + (needs_stub_method + || is_pointer + || i > 0), + types_seen, + methods); + } +} + +// If TYPE is an interface type, then add its method to *METHODS. +// This is for interface methods attached to an anonymous field. The +// parameters are as for add_methods_for_type. + +void +Type::add_interface_methods_for_type(const Type* type, + const Method::Field_indexes* field_indexes, + unsigned int depth, + Methods** methods) +{ + const Interface_type* it = type->interface_type(); + if (it == NULL) + return; + + const Typed_identifier_list* imethods = it->methods(); + if (imethods == NULL) + return; + + if (*methods == NULL) + *methods = new Methods(); + + for (Typed_identifier_list::const_iterator pm = imethods->begin(); + pm != imethods->end(); + ++pm) + { + Function_type* fntype = pm->type()->function_type(); + if (fntype == NULL) + { + // This is an error, but it should be reported elsewhere + // when we look at the methods for IT. + continue; + } + gcc_assert(!fntype->is_method()); + fntype = fntype->copy_with_receiver(const_cast<Type*>(type)); + Method* m = new Interface_method(pm->name(), pm->location(), fntype, + field_indexes, depth); + if (!(*methods)->insert(pm->name(), m)) + delete m; + } +} + +// Build stub methods for TYPE as needed. METHODS is the set of +// methods for the type. A stub method may be needed when a type +// inherits a method from an anonymous field. When we need the +// address of the method, as in a type descriptor, we need to build a +// little stub which does the required field dereferences and jumps to +// the real method. LOCATION is the location of the type definition. + +void +Type::build_stub_methods(Gogo* gogo, const Type* type, const Methods* methods, + source_location location) +{ + if (methods == NULL) + return; + for (Methods::const_iterator p = methods->begin(); + p != methods->end(); + ++p) + { + Method* m = p->second; + if (m->is_ambiguous() || !m->needs_stub_method()) + continue; + + const std::string& name(p->first); + + // Build a stub method. + + const Function_type* fntype = m->type(); + + static unsigned int counter; + char buf[100]; + snprintf(buf, sizeof buf, "$this%u", counter); + ++counter; + + Type* receiver_type = const_cast<Type*>(type); + if (!m->is_value_method()) + receiver_type = Type::make_pointer_type(receiver_type); + source_location receiver_location = m->receiver_location(); + Typed_identifier* receiver = new Typed_identifier(buf, receiver_type, + receiver_location); + + const Typed_identifier_list* fnparams = fntype->parameters(); + Typed_identifier_list* stub_params; + if (fnparams == NULL || fnparams->empty()) + stub_params = NULL; + else + { + // We give each stub parameter a unique name. + stub_params = new Typed_identifier_list(); + for (Typed_identifier_list::const_iterator pp = fnparams->begin(); + pp != fnparams->end(); + ++pp) + { + char pbuf[100]; + snprintf(pbuf, sizeof pbuf, "$p%u", counter); + stub_params->push_back(Typed_identifier(pbuf, pp->type(), + pp->location())); + ++counter; + } + } + + const Typed_identifier_list* fnresults = fntype->results(); + Typed_identifier_list* stub_results; + if (fnresults == NULL || fnresults->empty()) + stub_results = NULL; + else + { + // We create the result parameters without any names, since + // we won't refer to them. + stub_results = new Typed_identifier_list(); + for (Typed_identifier_list::const_iterator pr = fnresults->begin(); + pr != fnresults->end(); + ++pr) + stub_results->push_back(Typed_identifier("", pr->type(), + pr->location())); + } + + Function_type* stub_type = Type::make_function_type(receiver, + stub_params, + stub_results, + fntype->location()); + if (fntype->is_varargs()) + stub_type->set_is_varargs(); + + // We only create the function in the package which creates the + // type. + const Package* package; + if (type->named_type() == NULL) + package = NULL; + else + package = type->named_type()->named_object()->package(); + Named_object* stub; + if (package != NULL) + stub = Named_object::make_function_declaration(name, package, + stub_type, location); + else + { + stub = gogo->start_function(name, stub_type, false, + fntype->location()); + Type::build_one_stub_method(gogo, m, buf, stub_params, + fntype->is_varargs(), location); + gogo->finish_function(fntype->location()); + } + + m->set_stub_object(stub); + } +} + +// Build a stub method which adjusts the receiver as required to call +// METHOD. RECEIVER_NAME is the name we used for the receiver. +// PARAMS is the list of function parameters. + +void +Type::build_one_stub_method(Gogo* gogo, Method* method, + const char* receiver_name, + const Typed_identifier_list* params, + bool is_varargs, + source_location location) +{ + Named_object* receiver_object = gogo->lookup(receiver_name, NULL); + gcc_assert(receiver_object != NULL); + + Expression* expr = Expression::make_var_reference(receiver_object, location); + expr = Type::apply_field_indexes(expr, method->field_indexes(), location); + if (expr->type()->points_to() == NULL) + expr = Expression::make_unary(OPERATOR_AND, expr, location); + + Expression_list* arguments; + if (params == NULL || params->empty()) + arguments = NULL; + else + { + arguments = new Expression_list(); + for (Typed_identifier_list::const_iterator p = params->begin(); + p != params->end(); + ++p) + { + Named_object* param = gogo->lookup(p->name(), NULL); + gcc_assert(param != NULL); + Expression* param_ref = Expression::make_var_reference(param, + location); + arguments->push_back(param_ref); + } + } + + Expression* func = method->bind_method(expr, location); + gcc_assert(func != NULL); + Call_expression* call = Expression::make_call(func, arguments, is_varargs, + location); + size_t count = call->result_count(); + if (count == 0) + gogo->add_statement(Statement::make_statement(call)); + else + { + Expression_list* retvals = new Expression_list(); + if (count <= 1) + retvals->push_back(call); + else + { + for (size_t i = 0; i < count; ++i) + retvals->push_back(Expression::make_call_result(call, i)); + } + const Function* function = gogo->current_function()->func_value(); + const Typed_identifier_list* results = function->type()->results(); + Statement* retstat = Statement::make_return_statement(results, retvals, + location); + gogo->add_statement(retstat); + } +} + +// Apply FIELD_INDEXES to EXPR. The field indexes have to be applied +// in reverse order. + +Expression* +Type::apply_field_indexes(Expression* expr, + const Method::Field_indexes* field_indexes, + source_location location) +{ + if (field_indexes == NULL) + return expr; + expr = Type::apply_field_indexes(expr, field_indexes->next, location); + Struct_type* stype = expr->type()->deref()->struct_type(); + gcc_assert(stype != NULL + && field_indexes->field_index < stype->field_count()); + if (expr->type()->struct_type() == NULL) + { + gcc_assert(expr->type()->points_to() != NULL); + expr = Expression::make_unary(OPERATOR_MULT, expr, location); + gcc_assert(expr->type()->struct_type() == stype); + } + return Expression::make_field_reference(expr, field_indexes->field_index, + location); +} + +// Return whether NO is a method for which the receiver is a pointer. + +bool +Type::method_expects_pointer(const Named_object* no) +{ + const Function_type *fntype; + if (no->is_function()) + fntype = no->func_value()->type(); + else if (no->is_function_declaration()) + fntype = no->func_declaration_value()->type(); + else + gcc_unreachable(); + return fntype->receiver()->type()->points_to() != NULL; +} + +// Given a set of methods for a type, METHODS, return the method NAME, +// or NULL if there isn't one or if it is ambiguous. If IS_AMBIGUOUS +// is not NULL, then set *IS_AMBIGUOUS to true if the method exists +// but is ambiguous (and return NULL). + +Method* +Type::method_function(const Methods* methods, const std::string& name, + bool* is_ambiguous) +{ + if (is_ambiguous != NULL) + *is_ambiguous = false; + if (methods == NULL) + return NULL; + Methods::const_iterator p = methods->find(name); + if (p == methods->end()) + return NULL; + Method* m = p->second; + if (m->is_ambiguous()) + { + if (is_ambiguous != NULL) + *is_ambiguous = true; + return NULL; + } + return m; +} + +// Look for field or method NAME for TYPE. Return an Expression for +// the field or method bound to EXPR. If there is no such field or +// method, give an appropriate error and return an error expression. + +Expression* +Type::bind_field_or_method(Gogo* gogo, const Type* type, Expression* expr, + const std::string& name, + source_location location) +{ + if (type->deref()->is_error_type()) + return Expression::make_error(location); + + const Named_type* nt = type->deref()->named_type(); + const Struct_type* st = type->deref()->struct_type(); + const Interface_type* it = type->deref()->interface_type(); + + // If this is a pointer to a pointer, then it is possible that the + // pointed-to type has methods. + if (nt == NULL + && st == NULL + && it == NULL + && type->points_to() != NULL + && type->points_to()->points_to() != NULL) + { + expr = Expression::make_unary(OPERATOR_MULT, expr, location); + type = type->points_to(); + if (type->deref()->is_error_type()) + return Expression::make_error(location); + nt = type->points_to()->named_type(); + st = type->points_to()->struct_type(); + it = type->points_to()->interface_type(); + } + + bool receiver_can_be_pointer = (expr->type()->points_to() != NULL + || expr->is_addressable()); + std::vector<const Named_type*> seen; + bool is_method = false; + bool found_pointer_method = false; + std::string ambig1; + std::string ambig2; + if (Type::find_field_or_method(type, name, receiver_can_be_pointer, + &seen, NULL, &is_method, + &found_pointer_method, &ambig1, &ambig2)) + { + Expression* ret; + if (!is_method) + { + gcc_assert(st != NULL); + if (type->struct_type() == NULL) + { + gcc_assert(type->points_to() != NULL); + expr = Expression::make_unary(OPERATOR_MULT, expr, + location); + gcc_assert(expr->type()->struct_type() == st); + } + ret = st->field_reference(expr, name, location); + } + else if (it != NULL && it->find_method(name) != NULL) + ret = Expression::make_interface_field_reference(expr, name, + location); + else + { + Method* m; + if (nt != NULL) + m = nt->method_function(name, NULL); + else if (st != NULL) + m = st->method_function(name, NULL); + else + gcc_unreachable(); + gcc_assert(m != NULL); + if (!m->is_value_method() && expr->type()->points_to() == NULL) + expr = Expression::make_unary(OPERATOR_AND, expr, location); + ret = m->bind_method(expr, location); + } + gcc_assert(ret != NULL); + return ret; + } + else + { + if (!ambig1.empty()) + error_at(location, "%qs is ambiguous via %qs and %qs", + Gogo::message_name(name).c_str(), + Gogo::message_name(ambig1).c_str(), + Gogo::message_name(ambig2).c_str()); + else if (found_pointer_method) + error_at(location, "method requires a pointer"); + else if (nt == NULL && st == NULL && it == NULL) + error_at(location, + ("reference to field %qs in object which " + "has no fields or methods"), + Gogo::message_name(name).c_str()); + else + { + bool is_unexported; + if (!Gogo::is_hidden_name(name)) + is_unexported = false; + else + { + std::string unpacked = Gogo::unpack_hidden_name(name); + seen.clear(); + is_unexported = Type::is_unexported_field_or_method(gogo, type, + unpacked, + &seen); + } + if (is_unexported) + error_at(location, "reference to unexported field or method %qs", + Gogo::message_name(name).c_str()); + else + error_at(location, "reference to undefined field or method %qs", + Gogo::message_name(name).c_str()); + } + return Expression::make_error(location); + } +} + +// Look in TYPE for a field or method named NAME, return true if one +// is found. This looks through embedded anonymous fields and handles +// ambiguity. If a method is found, sets *IS_METHOD to true; +// otherwise, if a field is found, set it to false. If +// RECEIVER_CAN_BE_POINTER is false, then the receiver is a value +// whose address can not be taken. SEEN is used to avoid infinite +// recursion on invalid types. + +// When returning false, this sets *FOUND_POINTER_METHOD if we found a +// method we couldn't use because it requires a pointer. LEVEL is +// used for recursive calls, and can be NULL for a non-recursive call. +// When this function returns false because it finds that the name is +// ambiguous, it will store a path to the ambiguous names in *AMBIG1 +// and *AMBIG2. If the name is not found at all, *AMBIG1 and *AMBIG2 +// will be unchanged. + +// This function just returns whether or not there is a field or +// method, and whether it is a field or method. It doesn't build an +// expression to refer to it. If it is a method, we then look in the +// list of all methods for the type. If it is a field, the search has +// to be done again, looking only for fields, and building up the +// expression as we go. + +bool +Type::find_field_or_method(const Type* type, + const std::string& name, + bool receiver_can_be_pointer, + std::vector<const Named_type*>* seen, + int* level, + bool* is_method, + bool* found_pointer_method, + std::string* ambig1, + std::string* ambig2) +{ + // Named types can have locally defined methods. + const Named_type* nt = type->named_type(); + if (nt == NULL && type->points_to() != NULL) + nt = type->points_to()->named_type(); + if (nt != NULL) + { + Named_object* no = nt->find_local_method(name); + if (no != NULL) + { + if (receiver_can_be_pointer || !Type::method_expects_pointer(no)) + { + *is_method = true; + return true; + } + + // Record that we have found a pointer method in order to + // give a better error message if we don't find anything + // else. + *found_pointer_method = true; + } + + for (std::vector<const Named_type*>::const_iterator p = seen->begin(); + p != seen->end(); + ++p) + { + if (*p == nt) + { + // We've already seen this type when searching for methods. + return false; + } + } + } + + // Interface types can have methods. + const Interface_type* it = type->deref()->interface_type(); + if (it != NULL && it->find_method(name) != NULL) + { + *is_method = true; + return true; + } + + // Struct types can have fields. They can also inherit fields and + // methods from anonymous fields. + const Struct_type* st = type->deref()->struct_type(); + if (st == NULL) + return false; + const Struct_field_list* fields = st->fields(); + if (fields == NULL) + return false; + + if (nt != NULL) + seen->push_back(nt); + + int found_level = 0; + bool found_is_method = false; + std::string found_ambig1; + std::string found_ambig2; + const Struct_field* found_parent = NULL; + for (Struct_field_list::const_iterator pf = fields->begin(); + pf != fields->end(); + ++pf) + { + if (pf->field_name() == name) + { + *is_method = false; + if (nt != NULL) + seen->pop_back(); + return true; + } + + if (!pf->is_anonymous()) + continue; + + if (pf->type()->deref()->is_error_type() + || pf->type()->deref()->is_undefined()) + continue; + + Named_type* fnt = pf->type()->named_type(); + if (fnt == NULL) + fnt = pf->type()->deref()->named_type(); + gcc_assert(fnt != NULL); + + int sublevel = level == NULL ? 1 : *level + 1; + bool sub_is_method; + std::string subambig1; + std::string subambig2; + bool subfound = Type::find_field_or_method(fnt, + name, + receiver_can_be_pointer, + seen, + &sublevel, + &sub_is_method, + found_pointer_method, + &subambig1, + &subambig2); + if (!subfound) + { + if (!subambig1.empty()) + { + // The name was found via this field, but is ambiguous. + // if the ambiguity is lower or at the same level as + // anything else we have already found, then we want to + // pass the ambiguity back to the caller. + if (found_level == 0 || sublevel <= found_level) + { + found_ambig1 = pf->field_name() + '.' + subambig1; + found_ambig2 = pf->field_name() + '.' + subambig2; + found_level = sublevel; + } + } + } + else + { + // The name was found via this field. Use the level to see + // if we want to use this one, or whether it introduces an + // ambiguity. + if (found_level == 0 || sublevel < found_level) + { + found_level = sublevel; + found_is_method = sub_is_method; + found_ambig1.clear(); + found_ambig2.clear(); + found_parent = &*pf; + } + else if (sublevel > found_level) + ; + else if (found_ambig1.empty()) + { + // We found an ambiguity. + gcc_assert(found_parent != NULL); + found_ambig1 = found_parent->field_name(); + found_ambig2 = pf->field_name(); + } + else + { + // We found an ambiguity, but we already know of one. + // Just report the earlier one. + } + } + } + + // Here if we didn't find anything FOUND_LEVEL is 0. If we found + // something ambiguous, FOUND_LEVEL is not 0 and FOUND_AMBIG1 and + // FOUND_AMBIG2 are not empty. If we found the field, FOUND_LEVEL + // is not 0 and FOUND_AMBIG1 and FOUND_AMBIG2 are empty. + + if (nt != NULL) + seen->pop_back(); + + if (found_level == 0) + return false; + else if (!found_ambig1.empty()) + { + gcc_assert(!found_ambig1.empty()); + ambig1->assign(found_ambig1); + ambig2->assign(found_ambig2); + if (level != NULL) + *level = found_level; + return false; + } + else + { + if (level != NULL) + *level = found_level; + *is_method = found_is_method; + return true; + } +} + +// Return whether NAME is an unexported field or method for TYPE. + +bool +Type::is_unexported_field_or_method(Gogo* gogo, const Type* type, + const std::string& name, + std::vector<const Named_type*>* seen) +{ + const Named_type* nt = type->named_type(); + if (nt == NULL) + nt = type->deref()->named_type(); + if (nt != NULL) + { + if (nt->is_unexported_local_method(gogo, name)) + return true; + + for (std::vector<const Named_type*>::const_iterator p = seen->begin(); + p != seen->end(); + ++p) + { + if (*p == nt) + { + // We've already seen this type. + return false; + } + } + } + + type = type->deref(); + + const Interface_type* it = type->interface_type(); + if (it != NULL && it->is_unexported_method(gogo, name)) + return true; + + const Struct_type* st = type->struct_type(); + if (st != NULL && st->is_unexported_local_field(gogo, name)) + return true; + + if (st == NULL) + return false; + + const Struct_field_list* fields = st->fields(); + if (fields == NULL) + return false; + + if (nt != NULL) + seen->push_back(nt); + + for (Struct_field_list::const_iterator pf = fields->begin(); + pf != fields->end(); + ++pf) + { + if (pf->is_anonymous() + && !pf->type()->deref()->is_error_type() + && !pf->type()->deref()->is_undefined()) + { + Named_type* subtype = pf->type()->named_type(); + if (subtype == NULL) + subtype = pf->type()->deref()->named_type(); + if (subtype == NULL) + { + // This is an error, but it will be diagnosed elsewhere. + continue; + } + if (Type::is_unexported_field_or_method(gogo, subtype, name, seen)) + { + if (nt != NULL) + seen->pop_back(); + return true; + } + } + } + + if (nt != NULL) + seen->pop_back(); + + return false; +} + +// Class Forward_declaration. + +Forward_declaration_type::Forward_declaration_type(Named_object* named_object) + : Type(TYPE_FORWARD), + named_object_(named_object->resolve()), warned_(false) +{ + gcc_assert(this->named_object_->is_unknown() + || this->named_object_->is_type_declaration()); +} + +// Return the named object. + +Named_object* +Forward_declaration_type::named_object() +{ + return this->named_object_->resolve(); +} + +const Named_object* +Forward_declaration_type::named_object() const +{ + return this->named_object_->resolve(); +} + +// Return the name of the forward declared type. + +const std::string& +Forward_declaration_type::name() const +{ + return this->named_object()->name(); +} + +// Warn about a use of a type which has been declared but not defined. + +void +Forward_declaration_type::warn() const +{ + Named_object* no = this->named_object_->resolve(); + if (no->is_unknown()) + { + // The name was not defined anywhere. + if (!this->warned_) + { + error_at(this->named_object_->location(), + "use of undefined type %qs", + no->message_name().c_str()); + this->warned_ = true; + } + } + else if (no->is_type_declaration()) + { + // The name was seen as a type, but the type was never defined. + if (no->type_declaration_value()->using_type()) + { + error_at(this->named_object_->location(), + "use of undefined type %qs", + no->message_name().c_str()); + this->warned_ = true; + } + } + else + { + // The name was defined, but not as a type. + if (!this->warned_) + { + error_at(this->named_object_->location(), "expected type"); + this->warned_ = true; + } + } +} + +// Get the base type of a declaration. This gives an error if the +// type has not yet been defined. + +Type* +Forward_declaration_type::real_type() +{ + if (this->is_defined()) + return this->named_object()->type_value(); + else + { + this->warn(); + return Type::make_error_type(); + } +} + +const Type* +Forward_declaration_type::real_type() const +{ + if (this->is_defined()) + return this->named_object()->type_value(); + else + { + this->warn(); + return Type::make_error_type(); + } +} + +// Return whether the base type is defined. + +bool +Forward_declaration_type::is_defined() const +{ + return this->named_object()->is_type(); +} + +// Add a method. This is used when methods are defined before the +// type. + +Named_object* +Forward_declaration_type::add_method(const std::string& name, + Function* function) +{ + Named_object* no = this->named_object(); + if (no->is_unknown()) + no->declare_as_type(); + return no->type_declaration_value()->add_method(name, function); +} + +// Add a method declaration. This is used when methods are declared +// before the type. + +Named_object* +Forward_declaration_type::add_method_declaration(const std::string& name, + Function_type* type, + source_location location) +{ + Named_object* no = this->named_object(); + if (no->is_unknown()) + no->declare_as_type(); + Type_declaration* td = no->type_declaration_value(); + return td->add_method_declaration(name, type, location); +} + +// Traversal. + +int +Forward_declaration_type::do_traverse(Traverse* traverse) +{ + if (this->is_defined() + && Type::traverse(this->real_type(), traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + return TRAVERSE_CONTINUE; +} + +// Get a tree for the type. + +tree +Forward_declaration_type::do_get_tree(Gogo* gogo) +{ + if (this->is_defined()) + return Type::get_named_type_tree(gogo, this->real_type()); + + if (this->warned_) + return error_mark_node; + + // We represent an undefined type as a struct with no fields. That + // should work fine for the middle-end, since the same case can + // arise in C. + Named_object* no = this->named_object(); + tree type_tree = make_node(RECORD_TYPE); + tree id = no->get_id(gogo); + tree decl = build_decl(no->location(), TYPE_DECL, id, type_tree); + TYPE_NAME(type_tree) = decl; + layout_type(type_tree); + return type_tree; +} + +// Build a type descriptor for a forwarded type. + +Expression* +Forward_declaration_type::do_type_descriptor(Gogo* gogo, Named_type* name) +{ + if (!this->is_defined()) + return Expression::make_nil(BUILTINS_LOCATION); + else + { + Type* t = this->real_type(); + if (name != NULL) + return this->named_type_descriptor(gogo, t, name); + else + return Expression::make_type_descriptor(t, BUILTINS_LOCATION); + } +} + +// The reflection string. + +void +Forward_declaration_type::do_reflection(Gogo* gogo, std::string* ret) const +{ + this->append_reflection(this->real_type(), gogo, ret); +} + +// The mangled name. + +void +Forward_declaration_type::do_mangled_name(Gogo* gogo, std::string* ret) const +{ + if (this->is_defined()) + this->append_mangled_name(this->real_type(), gogo, ret); + else + { + const Named_object* no = this->named_object(); + std::string name; + if (no->package() == NULL) + name = gogo->package_name(); + else + name = no->package()->name(); + name += '.'; + name += Gogo::unpack_hidden_name(no->name()); + char buf[20]; + snprintf(buf, sizeof buf, "N%u_", + static_cast<unsigned int>(name.length())); + ret->append(buf); + ret->append(name); + } +} + +// Export a forward declaration. This can happen when a defined type +// refers to a type which is only declared (and is presumably defined +// in some other file in the same package). + +void +Forward_declaration_type::do_export(Export*) const +{ + // If there is a base type, that should be exported instead of this. + gcc_assert(!this->is_defined()); + + // We don't output anything. +} + +// Make a forward declaration. + +Type* +Type::make_forward_declaration(Named_object* named_object) +{ + return new Forward_declaration_type(named_object); +} + +// Class Typed_identifier_list. + +// Sort the entries by name. + +struct Typed_identifier_list_sort +{ + public: + bool + operator()(const Typed_identifier& t1, const Typed_identifier& t2) const + { return t1.name() < t2.name(); } +}; + +void +Typed_identifier_list::sort_by_name() +{ + std::sort(this->entries_.begin(), this->entries_.end(), + Typed_identifier_list_sort()); +} + +// Traverse types. + +int +Typed_identifier_list::traverse(Traverse* traverse) +{ + for (Typed_identifier_list::const_iterator p = this->begin(); + p != this->end(); + ++p) + { + if (Type::traverse(p->type(), traverse) == TRAVERSE_EXIT) + return TRAVERSE_EXIT; + } + return TRAVERSE_CONTINUE; +} + +// Copy the list. + +Typed_identifier_list* +Typed_identifier_list::copy() const +{ + Typed_identifier_list* ret = new Typed_identifier_list(); + for (Typed_identifier_list::const_iterator p = this->begin(); + p != this->end(); + ++p) + ret->push_back(Typed_identifier(p->name(), p->type(), p->location())); + return ret; +} diff --git a/gcc/go/gofrontend/types.h b/gcc/go/gofrontend/types.h new file mode 100644 index 000000000..8e91dfcab --- /dev/null +++ b/gcc/go/gofrontend/types.h @@ -0,0 +1,2809 @@ +// types.h -- Go frontend types. -*- C++ -*- + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef GO_TYPES_H +#define GO_TYPES_H + +class Gogo; +class Package; +class Traverse; +class Typed_identifier; +class Typed_identifier_list; +class Integer_type; +class Float_type; +class Complex_type; +class String_type; +class Function_type; +class Struct_field; +class Struct_field_list; +class Struct_type; +class Pointer_type; +class Array_type; +class Map_type; +class Channel_type; +class Interface_type; +class Named_type; +class Forward_declaration_type; +class Method; +class Methods; +class Type_hash_identical; +class Type_identical; +class Expression; +class Expression_list; +class Call_expression; +class Field_reference_expression; +class Bound_method_expression; +class Bindings; +class Named_object; +class Function; +class Translate_context; +class Export; +class Import; + +// Type codes used in type descriptors. These must match the values +// in libgo/runtime/go-type.h. They also match the values in the gc +// compiler in src/cmd/gc/reflect.c and src/pkg/runtime/type.go, +// although this is not required. + +static const int RUNTIME_TYPE_KIND_BOOL = 1; +static const int RUNTIME_TYPE_KIND_INT = 2; +static const int RUNTIME_TYPE_KIND_INT8 = 3; +static const int RUNTIME_TYPE_KIND_INT16 = 4; +static const int RUNTIME_TYPE_KIND_INT32 = 5; +static const int RUNTIME_TYPE_KIND_INT64 = 6; +static const int RUNTIME_TYPE_KIND_UINT = 7; +static const int RUNTIME_TYPE_KIND_UINT8 = 8; +static const int RUNTIME_TYPE_KIND_UINT16 = 9; +static const int RUNTIME_TYPE_KIND_UINT32 = 10; +static const int RUNTIME_TYPE_KIND_UINT64 = 11; +static const int RUNTIME_TYPE_KIND_UINTPTR = 12; +static const int RUNTIME_TYPE_KIND_FLOAT32 = 13; +static const int RUNTIME_TYPE_KIND_FLOAT64 = 14; +static const int RUNTIME_TYPE_KIND_COMPLEX64 = 15; +static const int RUNTIME_TYPE_KIND_COMPLEX128 = 16; +static const int RUNTIME_TYPE_KIND_ARRAY = 17; +static const int RUNTIME_TYPE_KIND_CHAN = 18; +static const int RUNTIME_TYPE_KIND_FUNC = 19; +static const int RUNTIME_TYPE_KIND_INTERFACE = 20; +static const int RUNTIME_TYPE_KIND_MAP = 21; +static const int RUNTIME_TYPE_KIND_PTR = 22; +static const int RUNTIME_TYPE_KIND_SLICE = 23; +static const int RUNTIME_TYPE_KIND_STRING = 24; +static const int RUNTIME_TYPE_KIND_STRUCT = 25; +static const int RUNTIME_TYPE_KIND_UNSAFE_POINTER = 26; + +// To build the complete list of methods for a named type we need to +// gather all methods from anonymous fields. Those methods may +// require an arbitrary set of indirections and field offsets. There +// is also the possibility of ambiguous methods, which we could ignore +// except that we want to give a better error message for that case. +// This is a base class. There are two types of methods: named +// methods, and methods which are inherited from an anonymous field of +// interface type. + +class Method +{ + public: + // For methods in anonymous types we need to know the sequence of + // field references used to extract the pointer to pass to the + // method. Since each method for a particular anonymous field will + // have the sequence of field indexes, and since the indexes can be + // shared going down the chain, we use a manually managed linked + // list. The first entry in the list is the field index for the + // last field, the one passed to the method. + + struct Field_indexes + { + const Field_indexes* next; + unsigned int field_index; + }; + + virtual ~Method() + { } + + // Get the list of field indexes. + const Field_indexes* + field_indexes() const + { return this->field_indexes_; } + + // Get the depth. + unsigned int + depth() const + { return this->depth_; } + + // Return whether this is a value method--a method which does not + // require a pointer expression. + bool + is_value_method() const + { return this->is_value_method_; } + + // Return whether we need a stub method--this is true if we can't + // just pass the main object to the method. + bool + needs_stub_method() const + { return this->needs_stub_method_; } + + // Return whether this is an ambiguous method name. + bool + is_ambiguous() const + { return this->is_ambiguous_; } + + // Note that this method is ambiguous. + void + set_is_ambiguous() + { this->is_ambiguous_ = true; } + + // Return the type of the method. + Function_type* + type() const + { return this->do_type(); } + + // Return the location of the method receiver. + source_location + receiver_location() const + { return this->do_receiver_location(); } + + // Return an expression which binds this method to EXPR. This is + // something which can be used with a function call. + Expression* + bind_method(Expression* expr, source_location location) const; + + // Return the named object for this method. This may only be called + // after methods are finalized. + Named_object* + named_object() const; + + // Get the stub object. + Named_object* + stub_object() const + { + gcc_assert(this->stub_ != NULL); + return this->stub_; + } + + // Set the stub object. + void + set_stub_object(Named_object* no) + { + gcc_assert(this->stub_ == NULL); + this->stub_ = no; + } + + protected: + // These objects are only built by the child classes. + Method(const Field_indexes* field_indexes, unsigned int depth, + bool is_value_method, bool needs_stub_method) + : field_indexes_(field_indexes), depth_(depth), stub_(NULL), + is_value_method_(is_value_method), needs_stub_method_(needs_stub_method), + is_ambiguous_(false) + { } + + // The named object for this method. + virtual Named_object* + do_named_object() const = 0; + + // The type of the method. + virtual Function_type* + do_type() const = 0; + + // Return the location of the method receiver. + virtual source_location + do_receiver_location() const = 0; + + // Bind a method to an object. + virtual Expression* + do_bind_method(Expression* expr, source_location location) const = 0; + + private: + // The sequence of field indexes used for this method. If this is + // NULL, then the method is defined for the current type. + const Field_indexes* field_indexes_; + // The depth at which this method was found. + unsigned int depth_; + // If a stub method is required, this is its object. This is only + // set after stub methods are built in finalize_methods. + Named_object* stub_; + // Whether this is a value method--a method that does not require a + // pointer. + bool is_value_method_; + // Whether a stub method is required. + bool needs_stub_method_; + // Whether this method is ambiguous. + bool is_ambiguous_; +}; + +// A named method. This is what you get with a method declaration, +// either directly on the type, or inherited from some anonymous +// embedded field. + +class Named_method : public Method +{ + public: + Named_method(Named_object* named_object, const Field_indexes* field_indexes, + unsigned int depth, bool is_value_method, + bool needs_stub_method) + : Method(field_indexes, depth, is_value_method, needs_stub_method), + named_object_(named_object) + { } + + protected: + // Get the Named_object for the method. + Named_object* + do_named_object() const + { return this->named_object_; } + + // The type of the method. + Function_type* + do_type() const; + + // Return the location of the method receiver. + source_location + do_receiver_location() const; + + // Bind a method to an object. + Expression* + do_bind_method(Expression* expr, source_location location) const; + + private: + // The method itself. For a method which needs a stub, this starts + // out as the underlying method, and is later replaced with the stub + // method. + Named_object* named_object_; +}; + +// An interface method. This is used when an interface appears as an +// anonymous field in a named struct. + +class Interface_method : public Method +{ + public: + Interface_method(const std::string& name, source_location location, + Function_type* fntype, const Field_indexes* field_indexes, + unsigned int depth) + : Method(field_indexes, depth, true, true), + name_(name), location_(location), fntype_(fntype) + { } + + protected: + // Get the Named_object for the method. This should never be + // called, as we always create a stub. + Named_object* + do_named_object() const + { gcc_unreachable(); } + + // The type of the method. + Function_type* + do_type() const + { return this->fntype_; } + + // Return the location of the method receiver. + source_location + do_receiver_location() const + { return this->location_; } + + // Bind a method to an object. + Expression* + do_bind_method(Expression* expr, source_location location) const; + + private: + // The name of the interface method to call. + std::string name_; + // The location of the definition of the interface method. + source_location location_; + // The type of the interface method. + Function_type* fntype_; +}; + +// A mapping from method name to Method. This is a wrapper around a +// hash table. + +class Methods +{ + private: + typedef Unordered_map(std::string, Method*) Method_map; + + public: + typedef Method_map::const_iterator const_iterator; + + Methods() + : methods_() + { } + + // Insert a new method. Returns true if it was inserted, false if + // it was overidden or ambiguous. + bool + insert(const std::string& name, Method* m); + + // The number of (unambiguous) methods. + size_t + count() const; + + // Iterate. + const_iterator + begin() const + { return this->methods_.begin(); } + + const_iterator + end() const + { return this->methods_.end(); } + + // Lookup. + const_iterator + find(const std::string& name) const + { return this->methods_.find(name); } + + private: + Method_map methods_; +}; + +// The base class for all types. + +class Type +{ + public: + // The types of types. + enum Type_classification + { + TYPE_ERROR, + TYPE_VOID, + TYPE_BOOLEAN, + TYPE_INTEGER, + TYPE_FLOAT, + TYPE_COMPLEX, + TYPE_STRING, + TYPE_SINK, + TYPE_FUNCTION, + TYPE_POINTER, + TYPE_NIL, + TYPE_CALL_MULTIPLE_RESULT, + TYPE_STRUCT, + TYPE_ARRAY, + TYPE_MAP, + TYPE_CHANNEL, + TYPE_INTERFACE, + TYPE_NAMED, + TYPE_FORWARD + }; + + virtual ~Type(); + + // Creators. + + static Type* + make_error_type(); + + static Type* + make_void_type(); + + // Get the unnamed bool type. + static Type* + make_boolean_type(); + + // Get the named type "bool". + static Named_type* + lookup_bool_type(); + + // Make the named type "bool". + static Named_type* + make_named_bool_type(); + + // Make an abstract integer type. + static Integer_type* + make_abstract_integer_type(); + + // Make a named integer type with a specified size. + // RUNTIME_TYPE_KIND is the code to use in reflection information, + // to distinguish int and int32. + static Named_type* + make_integer_type(const char* name, bool is_unsigned, int bits, + int runtime_type_kind); + + // Look up a named integer type. + static Named_type* + lookup_integer_type(const char* name); + + // Make an abstract floating point type. + static Float_type* + make_abstract_float_type(); + + // Make a named floating point type with a specific size. + // RUNTIME_TYPE_KIND is the code to use in reflection information, + // to distinguish float and float32. + static Named_type* + make_float_type(const char* name, int bits, int runtime_type_kind); + + // Look up a named float type. + static Named_type* + lookup_float_type(const char* name); + + // Make an abstract complex type. + static Complex_type* + make_abstract_complex_type(); + + // Make a named complex type with a specific size. + // RUNTIME_TYPE_KIND is the code to use in reflection information, + // to distinguish complex and complex64. + static Named_type* + make_complex_type(const char* name, int bits, int runtime_type_kind); + + // Look up a named complex type. + static Named_type* + lookup_complex_type(const char* name); + + // Get the unnamed string type. + static Type* + make_string_type(); + + // Get the named type "string". + static Named_type* + lookup_string_type(); + + // Make the named type "string". + static Named_type* + make_named_string_type(); + + static Type* + make_sink_type(); + + static Function_type* + make_function_type(Typed_identifier* receiver, + Typed_identifier_list* parameters, + Typed_identifier_list* results, + source_location); + + static Pointer_type* + make_pointer_type(Type*); + + static Type* + make_nil_type(); + + static Type* + make_call_multiple_result_type(Call_expression*); + + static Struct_type* + make_struct_type(Struct_field_list* fields, source_location); + + static Array_type* + make_array_type(Type* element_type, Expression* length); + + static Map_type* + make_map_type(Type* key_type, Type* value_type, source_location); + + static Channel_type* + make_channel_type(bool send, bool receive, Type*); + + static Interface_type* + make_interface_type(Typed_identifier_list* methods, source_location); + + static Type* + make_type_descriptor_type(); + + static Type* + make_type_descriptor_ptr_type(); + + static Named_type* + make_named_type(Named_object*, Type*, source_location); + + static Type* + make_forward_declaration(Named_object*); + + // Traverse a type. + static int + traverse(Type*, Traverse*); + + // Verify the type. This is called after parsing, and verifies that + // types are complete and meet the language requirements. This + // returns false if the type is invalid. + bool + verify() + { return this->do_verify(); } + + // Return true if two types are identical. If ERRORS_ARE_IDENTICAL, + // returns that an erroneous type is identical to any other type; + // this is used to avoid cascading errors. If this returns false, + // and REASON is not NULL, it may set *REASON. + static bool + are_identical(const Type* lhs, const Type* rhs, bool errors_are_identical, + std::string* reason); + + // Return true if two types are compatible for use in a binary + // operation, other than a shift, comparison, or channel send. This + // is an equivalence relation. + static bool + are_compatible_for_binop(const Type* t1, const Type* t2); + + // Return true if a value with type RHS is assignable to a variable + // with type LHS. This is not an equivalence relation. If this + // returns false, and REASON is not NULL, it sets *REASON. + static bool + are_assignable(const Type* lhs, const Type* rhs, std::string* reason); + + // Return true if a value with type RHS may be converted to type + // LHS. If this returns false, and REASON is not NULL, it sets + // *REASON. + static bool + are_convertible(const Type* lhs, const Type* rhs, std::string* reason); + + // Whether this type has any hidden fields which are not visible in + // the current compilation, such as a field whose name begins with a + // lower case letter in a struct imported from a different package. + // WITHIN is not NULL if we are looking at fields in a named type. + bool + has_hidden_fields(const Named_type* within, std::string* reason) const; + + // Return a hash code for this type for the method hash table. + // Types which are equivalent according to are_identical will have + // the same hash code. + unsigned int + hash_for_method(Gogo*) const; + + // Return the type classification. + Type_classification + classification() const + { return this->classification_; } + + // Return the base type for this type. This looks through forward + // declarations and names. Using this with a forward declaration + // which has not been defined will return an error type. + Type* + base(); + + const Type* + base() const; + + // Return the type skipping defined forward declarations. If this + // type is a forward declaration which has not been defined, it will + // return the Forward_declaration_type. This differs from base() in + // that it will return a Named_type, and for a + // Forward_declaration_type which is not defined it will return that + // type rather than an error type. + Type* + forwarded(); + + const Type* + forwarded() const; + + // Return true if this is a basic type: a type which is not composed + // of other types, and is not void. + bool + is_basic_type() const; + + // Return true if this is an abstract type--an integer, floating + // point, or complex type whose size has not been determined. + bool + is_abstract() const; + + // Return a non-abstract version of an abstract type. + Type* + make_non_abstract_type(); + + // Return true if this type is or contains a pointer. This + // determines whether the garbage collector needs to look at a value + // of this type. + bool + has_pointer() const + { return this->do_has_pointer(); } + + // Return true if this is an error type. An error type indicates a + // parsing error. + bool + is_error_type() const; + + // Return true if this is a void type. + bool + is_void_type() const + { return this->classification_ == TYPE_VOID; } + + // If this is an integer type, return the Integer_type. Otherwise, + // return NULL. This is a controlled dynamic_cast. + Integer_type* + integer_type() + { return this->convert<Integer_type, TYPE_INTEGER>(); } + + const Integer_type* + integer_type() const + { return this->convert<const Integer_type, TYPE_INTEGER>(); } + + // If this is a floating point type, return the Float_type. + // Otherwise, return NULL. This is a controlled dynamic_cast. + Float_type* + float_type() + { return this->convert<Float_type, TYPE_FLOAT>(); } + + const Float_type* + float_type() const + { return this->convert<const Float_type, TYPE_FLOAT>(); } + + // If this is a complex type, return the Complex_type. Otherwise, + // return NULL. + Complex_type* + complex_type() + { return this->convert<Complex_type, TYPE_COMPLEX>(); } + + const Complex_type* + complex_type() const + { return this->convert<const Complex_type, TYPE_COMPLEX>(); } + + // Return true if this is a boolean type. + bool + is_boolean_type() const + { return this->base()->classification_ == TYPE_BOOLEAN; } + + // Return true if this is an abstract boolean type. + bool + is_abstract_boolean_type() const + { return this->classification_ == TYPE_BOOLEAN; } + + // Return true if this is a string type. + bool + is_string_type() const + { return this->base()->classification_ == TYPE_STRING; } + + // Return true if this is an abstract string type. + bool + is_abstract_string_type() const + { return this->classification_ == TYPE_STRING; } + + // Return true if this is the sink type. This is the type of the + // blank identifier _. + bool + is_sink_type() const + { return this->base()->classification_ == TYPE_SINK; } + + // If this is a function type, return it. Otherwise, return NULL. + Function_type* + function_type() + { return this->convert<Function_type, TYPE_FUNCTION>(); } + + const Function_type* + function_type() const + { return this->convert<const Function_type, TYPE_FUNCTION>(); } + + // If this is a pointer type, return the type to which it points. + // Otherwise, return NULL. + Type* + points_to() const; + + // If this is a pointer type, return the type to which it points. + // Otherwise, return the type itself. + Type* + deref() + { + Type* pt = this->points_to(); + return pt != NULL ? pt : this; + } + + const Type* + deref() const + { + const Type* pt = this->points_to(); + return pt != NULL ? pt : this; + } + + // Return true if this is the nil type. We don't use base() here, + // because this can be called during parse, and there is no way to + // name the nil type anyhow. + bool + is_nil_type() const + { return this->classification_ == TYPE_NIL; } + + // Return true if this is the predeclared constant nil being used as + // a type. This is what the parser produces for type switches which + // use "case nil". + bool + is_nil_constant_as_type() const; + + // Return true if this is the return type of a function which + // returns multiple values. + bool + is_call_multiple_result_type() const + { return this->base()->classification_ == TYPE_CALL_MULTIPLE_RESULT; } + + // If this is a struct type, return it. Otherwise, return NULL. + Struct_type* + struct_type() + { return this->convert<Struct_type, TYPE_STRUCT>(); } + + const Struct_type* + struct_type() const + { return this->convert<const Struct_type, TYPE_STRUCT>(); } + + // If this is an array type, return it. Otherwise, return NULL. + Array_type* + array_type() + { return this->convert<Array_type, TYPE_ARRAY>(); } + + const Array_type* + array_type() const + { return this->convert<const Array_type, TYPE_ARRAY>(); } + + // Return whether if this is an open array type. + bool + is_open_array_type() const; + + // If this is a map type, return it. Otherwise, return NULL. + Map_type* + map_type() + { return this->convert<Map_type, TYPE_MAP>(); } + + const Map_type* + map_type() const + { return this->convert<const Map_type, TYPE_MAP>(); } + + // If this is a channel type, return it. Otherwise, return NULL. + Channel_type* + channel_type() + { return this->convert<Channel_type, TYPE_CHANNEL>(); } + + const Channel_type* + channel_type() const + { return this->convert<const Channel_type, TYPE_CHANNEL>(); } + + // If this is an interface type, return it. Otherwise, return NULL. + Interface_type* + interface_type() + { return this->convert<Interface_type, TYPE_INTERFACE>(); } + + const Interface_type* + interface_type() const + { return this->convert<const Interface_type, TYPE_INTERFACE>(); } + + // If this is a named type, return it. Otherwise, return NULL. + Named_type* + named_type(); + + const Named_type* + named_type() const; + + // If this is a forward declaration, return it. Otherwise, return + // NULL. + Forward_declaration_type* + forward_declaration_type() + { return this->convert_no_base<Forward_declaration_type, TYPE_FORWARD>(); } + + const Forward_declaration_type* + forward_declaration_type() const + { + return this->convert_no_base<const Forward_declaration_type, + TYPE_FORWARD>(); + } + + // Return true if this type is not yet defined. + bool + is_undefined() const; + + // Return true if this is the unsafe.pointer type. We currently + // represent that as pointer-to-void. + bool + is_unsafe_pointer_type() const + { return this->points_to() != NULL && this->points_to()->is_void_type(); } + + // Look for field or method NAME for TYPE. Return an expression for + // it, bound to EXPR. + static Expression* + bind_field_or_method(Gogo*, const Type* type, Expression* expr, + const std::string& name, source_location); + + // Return true if NAME is an unexported field or method of TYPE. + static bool + is_unexported_field_or_method(Gogo*, const Type*, const std::string&, + std::vector<const Named_type*>*); + + // This type was passed to the builtin function make. ARGS are the + // arguments passed to make after the type; this may be NULL if + // there were none. Issue any required errors. + bool + check_make_expression(Expression_list* args, source_location location) + { return this->do_check_make_expression(args, location); } + + // Convert the builtin named types. + static void + convert_builtin_named_types(Gogo*); + + // Return a tree representing this type. + tree + get_tree(Gogo*); + + // Return a tree representing a zero initialization for this type. + // This will be something like an INTEGER_CST or a CONSTRUCTOR. If + // IS_CLEAR is true, then the memory is known to be zeroed; in that + // case, this will return NULL if there is nothing to be done. + tree + get_init_tree(Gogo*, bool is_clear); + + // Like get_init_tree, but passing in the type to use for the + // initializer. + tree + get_typed_init_tree(Gogo* gogo, tree type_tree, bool is_clear) + { return this->do_get_init_tree(gogo, type_tree, is_clear); } + + // Return a tree for a make expression applied to this type. + tree + make_expression_tree(Translate_context* context, Expression_list* args, + source_location location) + { return this->do_make_expression_tree(context, args, location); } + + // Build a type descriptor entry for this type. Return a pointer to + // it. + tree + type_descriptor_pointer(Gogo* gogo); + + // Return the type reflection string for this type. + std::string + reflection(Gogo*) const; + + // Return a mangled name for the type. This is a name which can be + // used in assembler code. Identical types should have the same + // manged name. + std::string + mangled_name(Gogo*) const; + + // Export the type. + void + export_type(Export* exp) const + { this->do_export(exp); } + + // Import a type. + static Type* + import_type(Import*); + + protected: + Type(Type_classification); + + // Functions implemented by the child class. + + // Traverse the subtypes. + virtual int + do_traverse(Traverse*); + + // Verify the type. + virtual bool + do_verify() + { return true; } + + virtual bool + do_has_pointer() const + { return false; } + + virtual unsigned int + do_hash_for_method(Gogo*) const; + + virtual bool + do_check_make_expression(Expression_list* args, source_location); + + + virtual tree + do_get_tree(Gogo*) = 0; + + virtual tree + do_get_init_tree(Gogo*, tree, bool) = 0; + + virtual tree + do_make_expression_tree(Translate_context*, Expression_list*, + source_location); + + virtual Expression* + do_type_descriptor(Gogo*, Named_type* name) = 0; + + virtual void + do_reflection(Gogo*, std::string*) const = 0; + + + virtual void + do_mangled_name(Gogo*, std::string*) const = 0; + + virtual void + do_export(Export*) const; + + // Return whether an expression is an integer. + static bool + check_int_value(Expression*, const char*, source_location); + + // Return whether a method expects a pointer as the receiver. + static bool + method_expects_pointer(const Named_object*); + + // Finalize the methods for a type. + static void + finalize_methods(Gogo*, const Type*, source_location, Methods**); + + // Return a method from a set of methods. + static Method* + method_function(const Methods*, const std::string& name, + bool* is_ambiguous); + + // Return a composite literal for the type descriptor entry for a + // type. + static Expression* + type_descriptor(Gogo*, Type*); + + // Return a composite literal for the type descriptor entry for + // TYPE, using NAME as the name of the type. + static Expression* + named_type_descriptor(Gogo*, Type* type, Named_type* name); + + // Return a composite literal for a plain type descriptor for this + // type with the given kind and name. + Expression* + plain_type_descriptor(Gogo*, int runtime_type_kind, Named_type* name); + + // Build a composite literal for the basic type descriptor. + Expression* + type_descriptor_constructor(Gogo*, int runtime_type_kind, Named_type*, + const Methods*, bool only_value_methods); + + // Make a builtin struct type from a list of fields. + static Struct_type* + make_builtin_struct_type(int nfields, ...); + + // Make a builtin named type. + static Named_type* + make_builtin_named_type(const char* name, Type* type); + + // For the benefit of child class reflection string generation. + void + append_reflection(const Type* type, Gogo* gogo, std::string* ret) const + { type->do_reflection(gogo, ret); } + + // For the benefit of child class mangling. + void + append_mangled_name(const Type* type, Gogo* gogo, std::string* ret) const + { type->do_mangled_name(gogo, ret); } + + // Incorporate a string into a hash code. + static unsigned int + hash_string(const std::string&, unsigned int); + + // Return a tree for the underlying type of a named type. + static tree + get_named_type_tree(Gogo* gogo, Type* base_type) + { return base_type->get_tree_without_hash(gogo); } + + private: + // Convert to the desired type classification, or return NULL. This + // is a controlled dynamic_cast. + template<typename Type_class, Type_classification type_classification> + Type_class* + convert() + { + Type* base = this->base(); + return (base->classification_ == type_classification + ? static_cast<Type_class*>(base) + : NULL); + } + + template<typename Type_class, Type_classification type_classification> + const Type_class* + convert() const + { + const Type* base = this->base(); + return (base->classification_ == type_classification + ? static_cast<Type_class*>(base) + : NULL); + } + + template<typename Type_class, Type_classification type_classification> + Type_class* + convert_no_base() + { + return (this->classification_ == type_classification + ? static_cast<Type_class*>(this) + : NULL); + } + + template<typename Type_class, Type_classification type_classification> + const Type_class* + convert_no_base() const + { + return (this->classification_ == type_classification + ? static_cast<Type_class*>(this) + : NULL); + } + + // Get the hash and equality functions for a type. + void + type_functions(const char** hash_fn, const char** equal_fn) const; + + // Build a composite literal for the uncommon type information. + Expression* + uncommon_type_constructor(Gogo*, Type* uncommon_type, + Named_type*, const Methods*, + bool only_value_methods) const; + + // Build a composite literal for the methods. + Expression* + methods_constructor(Gogo*, Type* methods_type, const Methods*, + bool only_value_methods) const; + + // Build a composite literal for one method. + Expression* + method_constructor(Gogo*, Type* method_type, const std::string& name, + const Method*) const; + + static tree + build_receive_return_type(tree type); + + // A hash table we use to avoid infinite recursion. + typedef Unordered_set_hash(const Named_type*, Type_hash_identical, + Type_identical) Types_seen; + + // Add all methods for TYPE to the list of methods for THIS. + static void + add_methods_for_type(const Type* type, const Method::Field_indexes*, + unsigned int depth, bool, bool, Types_seen*, + Methods**); + + static void + add_local_methods_for_type(const Named_type* type, + const Method::Field_indexes*, + unsigned int depth, bool, bool, Methods**); + + static void + add_embedded_methods_for_type(const Type* type, + const Method::Field_indexes*, + unsigned int depth, bool, bool, Types_seen*, + Methods**); + + static void + add_interface_methods_for_type(const Type* type, + const Method::Field_indexes*, + unsigned int depth, Methods**); + + // Build stub methods for a type. + static void + build_stub_methods(Gogo*, const Type* type, const Methods* methods, + source_location); + + static void + build_one_stub_method(Gogo*, Method*, const char* receiver_name, + const Typed_identifier_list*, bool is_varargs, + source_location); + + static Expression* + apply_field_indexes(Expression*, const Method::Field_indexes*, + source_location); + + // Look for a field or method named NAME in TYPE. + static bool + find_field_or_method(const Type* type, const std::string& name, + bool receiver_can_be_pointer, + std::vector<const Named_type*>*, int* level, + bool* is_method, bool* found_pointer_method, + std::string* ambig1, std::string* ambig2); + + // Get a tree for a type without looking in the hash table for + // identical types. + tree + get_tree_without_hash(Gogo*); + + // A mapping from Type to tree, used to ensure that the GIMPLE + // representation of identical types is identical. + typedef Unordered_map_hash(const Type*, tree, Type_hash_identical, + Type_identical) Type_trees; + + static Type_trees type_trees; + + // A list of builtin named types. + static std::vector<Named_type*> named_builtin_types; + + // The type classification. + Type_classification classification_; + // The tree representation of the type, once it has been determined. + tree tree_; + // The decl for the type descriptor for this type. This starts out + // as NULL and is filled in as needed. + tree type_descriptor_decl_; +}; + +// Type hash table operations. + +class Type_hash_identical +{ + public: + unsigned int + operator()(const Type* type) const + { return type->hash_for_method(NULL); } +}; + +class Type_identical +{ + public: + bool + operator()(const Type* t1, const Type* t2) const + { return Type::are_identical(t1, t2, false, NULL); } +}; + +// An identifier with a type. + +class Typed_identifier +{ + public: + Typed_identifier(const std::string& name, Type* type, + source_location location) + : name_(name), type_(type), location_(location) + { } + + // Get the name. + const std::string& + name() const + { return this->name_; } + + // Get the type. + Type* + type() const + { return this->type_; } + + // Return the location where the name was seen. This is not always + // meaningful. + source_location + location() const + { return this->location_; } + + // Set the type--sometimes we see the identifier before the type. + void + set_type(Type* type) + { + gcc_assert(this->type_ == NULL || type->is_error_type()); + this->type_ = type; + } + + private: + // Identifier name. + std::string name_; + // Type. + Type* type_; + // The location where the name was seen. + source_location location_; +}; + +// A list of Typed_identifiers. + +class Typed_identifier_list +{ + public: + Typed_identifier_list() + : entries_() + { } + + // Whether the list is empty. + bool + empty() const + { return this->entries_.empty(); } + + // Return the number of entries in the list. + size_t + size() const + { return this->entries_.size(); } + + // Add an entry to the end of the list. + void + push_back(const Typed_identifier& td) + { this->entries_.push_back(td); } + + // Remove an entry from the end of the list. + void + pop_back() + { this->entries_.pop_back(); } + + // Set the type of entry I to TYPE. + void + set_type(size_t i, Type* type) + { + gcc_assert(i < this->entries_.size()); + this->entries_[i].set_type(type); + } + + // Sort the entries by name. + void + sort_by_name(); + + // Traverse types. + int + traverse(Traverse*); + + // Return the first and last elements. + Typed_identifier& + front() + { return this->entries_.front(); } + + const Typed_identifier& + front() const + { return this->entries_.front(); } + + Typed_identifier& + back() + { return this->entries_.back(); } + + const Typed_identifier& + back() const + { return this->entries_.back(); } + + const Typed_identifier& + at(size_t i) const + { return this->entries_.at(i); } + + void + set(size_t i, const Typed_identifier& t) + { this->entries_.at(i) = t; } + + void + resize(size_t c) + { + gcc_assert(c <= this->entries_.size()); + this->entries_.resize(c, Typed_identifier("", NULL, UNKNOWN_LOCATION)); + } + + // Iterators. + + typedef std::vector<Typed_identifier>::iterator iterator; + typedef std::vector<Typed_identifier>::const_iterator const_iterator; + + iterator + begin() + { return this->entries_.begin(); } + + const_iterator + begin() const + { return this->entries_.begin(); } + + iterator + end() + { return this->entries_.end(); } + + const_iterator + end() const + { return this->entries_.end(); } + + // Return a copy of this list. This returns an independent copy of + // the vector, but does not copy the types. + Typed_identifier_list* + copy() const; + + private: + std::vector<Typed_identifier> entries_; +}; + +// The type of an integer. + +class Integer_type : public Type +{ + public: + // Create a new integer type. + static Named_type* + create_integer_type(const char* name, bool is_unsigned, int bits, + int runtime_type_kind); + + // Look up an existing integer type. + static Named_type* + lookup_integer_type(const char* name); + + // Create an abstract integer type. + static Integer_type* + create_abstract_integer_type(); + + // Whether this is an abstract integer type. + bool + is_abstract() const + { return this->is_abstract_; } + + // Whether this is an unsigned type. + bool + is_unsigned() const + { return this->is_unsigned_; } + + // The number of bits. + int + bits() const + { return this->bits_; } + + // Whether this type is the same as T. + bool + is_identical(const Integer_type* t) const; + + protected: + unsigned int + do_hash_for_method(Gogo*) const; + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo*, tree, bool); + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string*) const; + + private: + Integer_type(bool is_abstract, bool is_unsigned, int bits, + int runtime_type_kind) + : Type(TYPE_INTEGER), + is_abstract_(is_abstract), is_unsigned_(is_unsigned), bits_(bits), + runtime_type_kind_(runtime_type_kind) + { } + + // Map names of integer types to the types themselves. + typedef std::map<std::string, Named_type*> Named_integer_types; + static Named_integer_types named_integer_types; + + // True if this is an abstract type. + bool is_abstract_; + // True if this is an unsigned type. + bool is_unsigned_; + // The number of bits. + int bits_; + // The runtime type code used in the type descriptor for this type. + int runtime_type_kind_; +}; + +// The type of a floating point number. + +class Float_type : public Type +{ + public: + // Create a new float type. + static Named_type* + create_float_type(const char* name, int bits, int runtime_type_kind); + + // Look up an existing float type. + static Named_type* + lookup_float_type(const char* name); + + // Create an abstract float type. + static Float_type* + create_abstract_float_type(); + + // Whether this is an abstract float type. + bool + is_abstract() const + { return this->is_abstract_; } + + // The number of bits. + int + bits() const + { return this->bits_; } + + // Whether this type is the same as T. + bool + is_identical(const Float_type* t) const; + + // Return a tree for this type without using a Gogo*. + tree + type_tree() const; + + protected: + unsigned int + do_hash_for_method(Gogo*) const; + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo*, tree, bool); + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string*) const; + + private: + Float_type(bool is_abstract, int bits, int runtime_type_kind) + : Type(TYPE_FLOAT), + is_abstract_(is_abstract), bits_(bits), + runtime_type_kind_(runtime_type_kind) + { } + + // Map names of float types to the types themselves. + typedef std::map<std::string, Named_type*> Named_float_types; + static Named_float_types named_float_types; + + // True if this is an abstract type. + bool is_abstract_; + // The number of bits in the floating point value. + int bits_; + // The runtime type code used in the type descriptor for this type. + int runtime_type_kind_; +}; + +// The type of a complex number. + +class Complex_type : public Type +{ + public: + // Create a new complex type. + static Named_type* + create_complex_type(const char* name, int bits, int runtime_type_kind); + + // Look up an existing complex type. + static Named_type* + lookup_complex_type(const char* name); + + // Create an abstract complex type. + static Complex_type* + create_abstract_complex_type(); + + // Whether this is an abstract complex type. + bool + is_abstract() const + { return this->is_abstract_; } + + // The number of bits: 64 or 128. + int bits() const + { return this->bits_; } + + // Whether this type is the same as T. + bool + is_identical(const Complex_type* t) const; + + // Return a tree for this type without using a Gogo*. + tree + type_tree() const; + + protected: + unsigned int + do_hash_for_method(Gogo*) const; + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo*, tree, bool); + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string*) const; + + private: + Complex_type(bool is_abstract, int bits, int runtime_type_kind) + : Type(TYPE_COMPLEX), + is_abstract_(is_abstract), bits_(bits), + runtime_type_kind_(runtime_type_kind) + { } + + // Map names of complex types to the types themselves. + typedef std::map<std::string, Named_type*> Named_complex_types; + static Named_complex_types named_complex_types; + + // True if this is an abstract type. + bool is_abstract_; + // The number of bits in the complex value--64 or 128. + int bits_; + // The runtime type code used in the type descriptor for this type. + int runtime_type_kind_; +}; + +// The type of a string. + +class String_type : public Type +{ + public: + String_type() + : Type(TYPE_STRING) + { } + + // Return a tree for the length of STRING. + static tree + length_tree(Gogo*, tree string); + + // Return a tree which points to the bytes of STRING. + static tree + bytes_tree(Gogo*, tree string); + + protected: + bool + do_has_pointer() const + { return true; } + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo* gogo, tree, bool); + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string* ret) const; + + private: + // The named string type. + static Named_type* string_type_; +}; + +// The type of a function. + +class Function_type : public Type +{ + public: + Function_type(Typed_identifier* receiver, Typed_identifier_list* parameters, + Typed_identifier_list* results, source_location location) + : Type(TYPE_FUNCTION), + receiver_(receiver), parameters_(parameters), results_(results), + location_(location), is_varargs_(false), is_builtin_(false) + { } + + // Get the receiver. + const Typed_identifier* + receiver() const + { return this->receiver_; } + + // Get the return names and types. + const Typed_identifier_list* + results() const + { return this->results_; } + + // Get the parameter names and types. + const Typed_identifier_list* + parameters() const + { return this->parameters_; } + + // Whether this is a varargs function. + bool + is_varargs() const + { return this->is_varargs_; } + + // Whether this is a builtin function. + bool + is_builtin() const + { return this->is_builtin_; } + + // The location where this type was defined. + source_location + location() const + { return this->location_; } + + // Return whether this is a method type. + bool + is_method() const + { return this->receiver_ != NULL; } + + // Whether T is a valid redeclaration of this type. This is called + // when a function is declared more than once. + bool + is_valid_redeclaration(const Function_type* t, std::string*) const; + + // Whether this type is the same as T. + bool + is_identical(const Function_type* t, bool ignore_receiver, + bool errors_are_identical, std::string*) const; + + // Record that this is a varargs function. + void + set_is_varargs() + { this->is_varargs_ = true; } + + // Record that this is a builtin function. + void + set_is_builtin() + { this->is_builtin_ = true; } + + // Import a function type. + static Function_type* + do_import(Import*); + + // Return a copy of this type without a receiver. This is only + // valid for a method type. + Function_type* + copy_without_receiver() const; + + // Return a copy of this type with a receiver. This is used when an + // interface method is attached to a named or struct type. + Function_type* + copy_with_receiver(Type*) const; + + static Type* + make_function_type_descriptor_type(); + + protected: + int + do_traverse(Traverse*); + + // A trampoline function has a pointer which matters for GC. + bool + do_has_pointer() const + { return true; } + + unsigned int + do_hash_for_method(Gogo*) const; + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo*, tree, bool); + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string*) const; + + void + do_export(Export*) const; + + private: + Expression* + type_descriptor_params(Type*, const Typed_identifier*, + const Typed_identifier_list*); + + // The receiver name and type. This will be NULL for a normal + // function, non-NULL for a method. + Typed_identifier* receiver_; + // The parameter names and types. + Typed_identifier_list* parameters_; + // The result names and types. This will be NULL if no result was + // specified. + Typed_identifier_list* results_; + // The location where this type was defined. This exists solely to + // give a location for the fields of the struct if this function + // returns multiple values. + source_location location_; + // Whether this function takes a variable number of arguments. + bool is_varargs_; + // Whether this is a special builtin function which can not simply + // be called. This is used for len, cap, etc. + bool is_builtin_; +}; + +// The type of a pointer. + +class Pointer_type : public Type +{ + public: + Pointer_type(Type* to_type) + : Type(TYPE_POINTER), + to_type_(to_type) + {} + + Type* + points_to() const + { return this->to_type_; } + + // Import a pointer type. + static Pointer_type* + do_import(Import*); + + static Type* + make_pointer_type_descriptor_type(); + + protected: + int + do_traverse(Traverse*); + + bool + do_has_pointer() const + { return true; } + + unsigned int + do_hash_for_method(Gogo*) const; + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo*, tree, bool); + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string*) const; + + void + do_export(Export*) const; + + private: + // The type to which this type points. + Type* to_type_; +}; + +// The type of a field in a struct. + +class Struct_field +{ + public: + explicit Struct_field(const Typed_identifier& typed_identifier) + : typed_identifier_(typed_identifier), tag_(NULL) + { } + + // The field name. + const std::string& + field_name() const; + + // The field type. + Type* + type() const + { return this->typed_identifier_.type(); } + + // The field location. + source_location + location() const + { return this->typed_identifier_.location(); } + + // Whether the field has a tag. + bool + has_tag() const + { return this->tag_ != NULL; } + + // The tag. + const std::string& + tag() const + { + gcc_assert(this->tag_ != NULL); + return *this->tag_; + } + + // Whether this is an anonymous field. + bool + is_anonymous() const + { return this->typed_identifier_.name().empty(); } + + // Set the tag. FIXME: This is never freed. + void + set_tag(const std::string& tag) + { this->tag_ = new std::string(tag); } + + // Set the type. This is only used in error cases. + void + set_type(Type* type) + { this->typed_identifier_.set_type(type); } + + private: + // The field name, type, and location. + Typed_identifier typed_identifier_; + // The field tag. This is NULL if the field has no tag. + std::string* tag_; +}; + +// A list of struct fields. + +class Struct_field_list +{ + public: + Struct_field_list() + : entries_() + { } + + // Whether the list is empty. + bool + empty() const + { return this->entries_.empty(); } + + // Return the number of entries. + size_t + size() const + { return this->entries_.size(); } + + // Add an entry to the end of the list. + void + push_back(const Struct_field& sf) + { this->entries_.push_back(sf); } + + // Index into the list. + const Struct_field& + at(size_t i) const + { return this->entries_.at(i); } + + // Last entry in list. + Struct_field& + back() + { return this->entries_.back(); } + + // Iterators. + + typedef std::vector<Struct_field>::iterator iterator; + typedef std::vector<Struct_field>::const_iterator const_iterator; + + iterator + begin() + { return this->entries_.begin(); } + + const_iterator + begin() const + { return this->entries_.begin(); } + + iterator + end() + { return this->entries_.end(); } + + const_iterator + end() const + { return this->entries_.end(); } + + private: + std::vector<Struct_field> entries_; +}; + +// The type of a struct. + +class Struct_type : public Type +{ + public: + Struct_type(Struct_field_list* fields, source_location location) + : Type(TYPE_STRUCT), + fields_(fields), location_(location), all_methods_(NULL) + { } + + // Return the field NAME. This only looks at local fields, not at + // embedded types. If the field is found, and PINDEX is not NULL, + // this sets *PINDEX to the field index. If the field is not found, + // this returns NULL. + const Struct_field* + find_local_field(const std::string& name, unsigned int *pindex) const; + + // Return the field number INDEX. + const Struct_field* + field(unsigned int index) const + { return &this->fields_->at(index); } + + // Get the struct fields. + const Struct_field_list* + fields() const + { return this->fields_; } + + // Return the number of fields. + size_t + field_count() const + { return this->fields_->size(); } + + // Push a new field onto the end of the struct. This is used when + // building a closure variable. + void + push_field(const Struct_field& sf) + { this->fields_->push_back(sf); } + + // Return an expression referring to field NAME in STRUCT_EXPR, or + // NULL if there is no field with that name. + Field_reference_expression* + field_reference(Expression* struct_expr, const std::string& name, + source_location) const; + + // Return the total number of fields, including embedded fields. + // This is the number of values which can appear in a conversion to + // this type. + unsigned int + total_field_count() const; + + // Whether this type is identical with T. + bool + is_identical(const Struct_type* t, bool errors_are_identical) const; + + // Whether this struct type has any hidden fields. This returns + // true if any fields have hidden names, or if any non-pointer + // anonymous fields have types with hidden fields. + bool + struct_has_hidden_fields(const Named_type* within, std::string*) const; + + // Return whether NAME is a local field which is not exported. This + // is only used for better error reporting. + bool + is_unexported_local_field(Gogo*, const std::string& name) const; + + // If this is an unnamed struct, build the complete list of methods, + // including those from anonymous fields, and build methods stubs if + // needed. + void + finalize_methods(Gogo*); + + // Return whether this type has any methods. This should only be + // called after the finalize_methods pass. + bool + has_any_methods() const + { return this->all_methods_ != NULL; } + + // Return the methods for tihs type. This should only be called + // after the finalize_methods pass. + const Methods* + methods() const + { return this->all_methods_; } + + // Return the method to use for NAME. This returns NULL if there is + // no such method or if the method is ambiguous. When it returns + // NULL, this sets *IS_AMBIGUOUS if the method name is ambiguous. + Method* + method_function(const std::string& name, bool* is_ambiguous) const; + + // Traverse just the field types of a struct type. + int + traverse_field_types(Traverse* traverse) + { return this->do_traverse(traverse); } + + // Import a struct type. + static Struct_type* + do_import(Import*); + + // Fill in the fields for a named struct type. + tree + fill_in_tree(Gogo*, tree); + + static Type* + make_struct_type_descriptor_type(); + + protected: + int + do_traverse(Traverse*); + + bool + do_verify(); + + bool + do_has_pointer() const; + + unsigned int + do_hash_for_method(Gogo*) const; + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo*, tree, bool); + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string*) const; + + void + do_export(Export*) const; + + private: + // Used to avoid infinite loops in field_reference_depth. + struct Saw_named_type + { + Saw_named_type* next; + Named_type* nt; + }; + + Field_reference_expression* + field_reference_depth(Expression* struct_expr, const std::string& name, + source_location, Saw_named_type*, + unsigned int* depth) const; + + // The fields of the struct. + Struct_field_list* fields_; + // The place where the struct was declared. + source_location location_; + // If this struct is unnamed, a list of methods. + Methods* all_methods_; +}; + +// The type of an array. + +class Array_type : public Type +{ + public: + Array_type(Type* element_type, Expression* length) + : Type(TYPE_ARRAY), + element_type_(element_type), length_(length), length_tree_(NULL) + { } + + // Return the element type. + Type* + element_type() const + { return this->element_type_; } + + // Return the length. This will return NULL for an open array. + Expression* + length() const + { return this->length_; } + + // Whether this type is identical with T. + bool + is_identical(const Array_type* t, bool errors_are_identical) const; + + // Whether this type has any hidden fields. + bool + array_has_hidden_fields(const Named_type* within, std::string* reason) const + { return this->element_type_->has_hidden_fields(within, reason); } + + // Return a tree for the pointer to the values in an array. + tree + value_pointer_tree(Gogo*, tree array) const; + + // Return a tree for the length of an array with this type. + tree + length_tree(Gogo*, tree array); + + // Return a tree for the capacity of an array with this type. + tree + capacity_tree(Gogo*, tree array); + + // Import an array type. + static Array_type* + do_import(Import*); + + // Fill in the fields for a named array type. + tree + fill_in_array_tree(Gogo*, tree); + + // Fill in the fields for a named slice type. + tree + fill_in_slice_tree(Gogo*, tree); + + static Type* + make_array_type_descriptor_type(); + + static Type* + make_slice_type_descriptor_type(); + + protected: + int + do_traverse(Traverse* traverse); + + bool + do_verify(); + + bool + do_has_pointer() const + { + return this->length_ == NULL || this->element_type_->has_pointer(); + } + + unsigned int + do_hash_for_method(Gogo*) const; + + bool + do_check_make_expression(Expression_list*, source_location); + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo*, tree, bool); + + tree + do_make_expression_tree(Translate_context*, Expression_list*, + source_location); + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string*) const; + + void + do_export(Export*) const; + + private: + bool + verify_length(); + + tree + get_length_tree(Gogo*); + + Expression* + array_type_descriptor(Gogo*, Named_type*); + + Expression* + slice_type_descriptor(Gogo*, Named_type*); + + // The type of elements of the array. + Type* element_type_; + // The number of elements. This may be NULL. + Expression* length_; + // The length as a tree. We only want to compute this once. + tree length_tree_; +}; + +// The type of a map. + +class Map_type : public Type +{ + public: + Map_type(Type* key_type, Type* val_type, source_location location) + : Type(TYPE_MAP), + key_type_(key_type), val_type_(val_type), location_(location) + { } + + // Return the key type. + Type* + key_type() const + { return this->key_type_; } + + // Return the value type. + Type* + val_type() const + { return this->val_type_; } + + // Whether this type is identical with T. + bool + is_identical(const Map_type* t, bool errors_are_identical) const; + + // Import a map type. + static Map_type* + do_import(Import*); + + static Type* + make_map_type_descriptor_type(); + + protected: + int + do_traverse(Traverse*); + + bool + do_verify(); + + bool + do_has_pointer() const + { return true; } + + unsigned int + do_hash_for_method(Gogo*) const; + + bool + do_check_make_expression(Expression_list*, source_location); + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo*, tree, bool); + + tree + do_make_expression_tree(Translate_context*, Expression_list*, + source_location); + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string*) const; + + void + do_export(Export*) const; + + private: + // The key type. + Type* key_type_; + // The value type. + Type* val_type_; + // Where the type was defined. + source_location location_; +}; + +// The type of a channel. + +class Channel_type : public Type +{ + public: + Channel_type(bool may_send, bool may_receive, Type* element_type) + : Type(TYPE_CHANNEL), + may_send_(may_send), may_receive_(may_receive), + element_type_(element_type) + { gcc_assert(may_send || may_receive); } + + // Whether this channel can send data. + bool + may_send() const + { return this->may_send_; } + + // Whether this channel can receive data. + bool + may_receive() const + { return this->may_receive_; } + + // The type of the values that may be sent on this channel. This is + // NULL if any type may be sent. + Type* + element_type() const + { return this->element_type_; } + + // Whether this type is identical with T. + bool + is_identical(const Channel_type* t, bool errors_are_identical) const; + + // Import a channel type. + static Channel_type* + do_import(Import*); + + static Type* + make_chan_type_descriptor_type(); + + protected: + int + do_traverse(Traverse* traverse) + { return Type::traverse(this->element_type_, traverse); } + + bool + do_has_pointer() const + { return true; } + + unsigned int + do_hash_for_method(Gogo*) const; + + bool + do_check_make_expression(Expression_list*, source_location); + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo*, tree, bool); + + tree + do_make_expression_tree(Translate_context*, Expression_list*, + source_location); + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string*) const; + + void + do_export(Export*) const; + + private: + // Whether this channel can send data. + bool may_send_; + // Whether this channel can receive data. + bool may_receive_; + // The types of elements which may be sent on this channel. If this + // is NULL, it means that any type may be sent. + Type* element_type_; +}; + +// An interface type. + +class Interface_type : public Type +{ + public: + Interface_type(Typed_identifier_list* methods, source_location location) + : Type(TYPE_INTERFACE), + methods_(methods), location_(location) + { gcc_assert(methods == NULL || !methods->empty()); } + + // The location where the interface type was defined. + source_location + location() const + { return this->location_; } + + // Return whether this is an empty interface. + bool + is_empty() const + { return this->methods_ == NULL; } + + // Return the list of methods. This will return NULL for an empty + // interface. + const Typed_identifier_list* + methods() const + { return this->methods_; } + + // Return the number of methods. + size_t + method_count() const + { return this->methods_ == NULL ? 0 : this->methods_->size(); } + + // Return the method NAME, or NULL. + const Typed_identifier* + find_method(const std::string& name) const; + + // Return the zero-based index of method NAME. + size_t + method_index(const std::string& name) const; + + // Finalize the methods. This handles interface inheritance. + void + finalize_methods(); + + // Return true if T implements this interface. If this returns + // false, and REASON is not NULL, it sets *REASON to the reason that + // it fails. + bool + implements_interface(const Type* t, std::string* reason) const; + + // Whether this type is identical with T. REASON is as in + // implements_interface. + bool + is_identical(const Interface_type* t, bool errors_are_identical) const; + + // Whether we can assign T to this type. is_identical is known to + // be false. + bool + is_compatible_for_assign(const Interface_type*, std::string* reason) const; + + // Return whether NAME is a method which is not exported. This is + // only used for better error reporting. + bool + is_unexported_method(Gogo*, const std::string& name) const; + + // Import an interface type. + static Interface_type* + do_import(Import*); + + // Make a struct for an empty interface type. + static tree + empty_type_tree(Gogo*); + + // Make a struct for non-empty interface type. + static tree + non_empty_type_tree(source_location); + + // Fill in the fields for a named interface type. + tree + fill_in_tree(Gogo*, tree); + + static Type* + make_interface_type_descriptor_type(); + + protected: + int + do_traverse(Traverse*); + + bool + do_has_pointer() const + { return true; } + + unsigned int + do_hash_for_method(Gogo*) const; + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo* gogo, tree, bool); + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string*) const; + + void + do_export(Export*) const; + + private: + // The list of methods associated with the interface. This will be + // NULL for the empty interface. + Typed_identifier_list* methods_; + // The location where the interface was defined. + source_location location_; +}; + +// The value we keep for a named type. This lets us get the right +// name when we convert to trees. Note that we don't actually keep +// the name here; the name is in the Named_object which points to +// this. This object exists to hold a unique tree which represents +// the type. + +class Named_type : public Type +{ + public: + Named_type(Named_object* named_object, Type* type, source_location location) + : Type(TYPE_NAMED), + named_object_(named_object), in_function_(NULL), type_(type), + local_methods_(NULL), all_methods_(NULL), + interface_method_tables_(NULL), pointer_interface_method_tables_(NULL), + location_(location), named_tree_(NULL), dependencies_(), + is_visible_(true), is_error_(false), is_converted_(false), + is_circular_(false), seen_(0) + { } + + // Return the associated Named_object. This holds the actual name. + Named_object* + named_object() + { return this->named_object_; } + + const Named_object* + named_object() const + { return this->named_object_; } + + // Set the Named_object. This is used when we see a type + // declaration followed by a type. + void + set_named_object(Named_object* no) + { this->named_object_ = no; } + + // Return the function in which this type is defined. This will + // return NULL for a type defined in global scope. + const Named_object* + in_function() const + { return this->in_function_; } + + // Set the function in which this type is defined. + void + set_in_function(Named_object* f) + { this->in_function_ = f; } + + // Return the name of the type. + const std::string& + name() const; + + // Return the name of the type for an error message. The difference + // is that if the type is defined in a different package, this will + // return PACKAGE.NAME. + std::string + message_name() const; + + // Return the underlying type. + Type* + real_type() + { return this->type_; } + + const Type* + real_type() const + { return this->type_; } + + // Return the location. + source_location + location() const + { return this->location_; } + + // Whether this type is visible. This only matters when parsing. + bool + is_visible() const + { return this->is_visible_; } + + // Mark this type as visible. + void + set_is_visible() + { this->is_visible_ = true; } + + // Mark this type as invisible. + void + clear_is_visible() + { this->is_visible_ = false; } + + // Whether this is a builtin type. + bool + is_builtin() const + { return this->location_ == BUILTINS_LOCATION; } + + // Whether this is a circular type: a pointer or function type that + // refers to itself, which is not possible in C. + bool + is_circular() const + { return this->is_circular_; } + + // Return the base type for this type. + Type* + named_base(); + + const Type* + named_base() const; + + // Return whether this is an error type. + bool + is_named_error_type() const; + + // Add a method to this type. + Named_object* + add_method(const std::string& name, Function*); + + // Add a method declaration to this type. + Named_object* + add_method_declaration(const std::string& name, Package* package, + Function_type* type, source_location location); + + // Add an existing method--one defined before the type itself was + // defined--to a type. + void + add_existing_method(Named_object*); + + // Look up a local method. + Named_object* + find_local_method(const std::string& name) const; + + // Return the list of local methods. + const Bindings* + local_methods() const + { return this->local_methods_; } + + // Build the complete list of methods, including those from + // anonymous fields, and build method stubs if needed. + void + finalize_methods(Gogo*); + + // Return whether this type has any methods. This should only be + // called after the finalize_methods pass. + bool + has_any_methods() const + { return this->all_methods_ != NULL; } + + // Return the methods for this type. This should only be called + // after the finalized_methods pass. + const Methods* + methods() const + { return this->all_methods_; } + + // Return the method to use for NAME. This returns NULL if there is + // no such method or if the method is ambiguous. When it returns + // NULL, this sets *IS_AMBIGUOUS if the method name is ambiguous. + Method* + method_function(const std::string& name, bool *is_ambiguous) const; + + // Return whether NAME is a known field or method which is not + // exported. This is only used for better error reporting. + bool + is_unexported_local_method(Gogo*, const std::string& name) const; + + // Return a pointer to the interface method table for this type for + // the interface INTERFACE. If IS_POINTER is true, set the type + // descriptor to a pointer to this type, otherwise set it to this + // type. + tree + interface_method_table(Gogo*, const Interface_type* interface, + bool is_pointer); + + // Whether this type has any hidden fields. + bool + named_type_has_hidden_fields(std::string* reason) const; + + // Note that a type must be converted to the backend representation + // before we convert this type. + void + add_dependency(Named_type* nt) + { this->dependencies_.push_back(nt); } + + // Export the type. + void + export_named_type(Export*, const std::string& name) const; + + // Import a named type. + static void + import_named_type(Import*, Named_type**); + + // Initial conversion to backend representation. + void + convert(Gogo*); + + protected: + int + do_traverse(Traverse* traverse) + { return Type::traverse(this->type_, traverse); } + + bool + do_verify(); + + bool + do_has_pointer() const; + + unsigned int + do_hash_for_method(Gogo*) const; + + bool + do_check_make_expression(Expression_list* args, source_location location) + { return this->type_->check_make_expression(args, location); } + + tree + do_get_tree(Gogo*); + + tree + do_get_init_tree(Gogo* gogo, tree type_tree, bool is_clear) + { return this->type_->get_typed_init_tree(gogo, type_tree, is_clear); } + + tree + do_make_expression_tree(Translate_context* context, Expression_list* args, + source_location location) + { return this->type_->make_expression_tree(context, args, location); } + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string* ret) const; + + void + do_export(Export*) const; + + private: + // Create the placeholder during conversion. + void + create_placeholder(Gogo*); + + // A mapping from interfaces to the associated interface method + // tables for this type. This maps to a decl. + typedef Unordered_map_hash(const Interface_type*, tree, Type_hash_identical, + Type_identical) Interface_method_tables; + + // A pointer back to the Named_object for this type. + Named_object* named_object_; + // If this type is defined in a function, a pointer back to the + // function in which it is defined. + Named_object* in_function_; + // The actual type. + Type* type_; + // The list of methods defined for this type. Any named type can + // have methods. + Bindings* local_methods_; + // The full list of methods for this type, including methods + // declared for anonymous fields. + Methods* all_methods_; + // A mapping from interfaces to the associated interface method + // tables for this type. + Interface_method_tables* interface_method_tables_; + // A mapping from interfaces to the associated interface method + // tables for pointers to this type. + Interface_method_tables* pointer_interface_method_tables_; + // The location where this type was defined. + source_location location_; + // The tree for this type while converting to GENERIC. This is used + // to avoid endless recursion when a named type refers to itself. + tree named_tree_; + // A list of types which must be converted to the backend + // representation before this type can be converted. This is for + // cases like + // type S1 { p *S2 } + // type S2 { s S1 } + // where we can't convert S2 to the backend representation unless we + // have converted S1. + std::vector<Named_type*> dependencies_; + // Whether this type is visible. This is false if this type was + // created because it was referenced by an imported object, but the + // type itself was not exported. This will always be true for types + // created in the current package. + bool is_visible_; + // Whether this type is erroneous. + bool is_error_; + // Whether this type has been converted to the backend + // representation. + bool is_converted_; + // Whether this is a pointer or function type which refers to the + // type itself. + bool is_circular_; + // In a recursive operation such as has_hidden_fields, this flag is + // used to prevent infinite recursion when a type refers to itself. + // This is mutable because it is always reset to false when the + // function exits. + mutable int seen_; +}; + +// A forward declaration. This handles a type which has been declared +// but not defined. + +class Forward_declaration_type : public Type +{ + public: + Forward_declaration_type(Named_object* named_object); + + // The named object associated with this type declaration. This + // will be resolved. + Named_object* + named_object(); + + const Named_object* + named_object() const; + + // Return the name of the type. + const std::string& + name() const; + + // Return the type to which this points. Give an error if the type + // has not yet been defined. + Type* + real_type(); + + const Type* + real_type() const; + + // Whether the base type has been defined. + bool + is_defined() const; + + // Add a method to this type. + Named_object* + add_method(const std::string& name, Function*); + + // Add a method declaration to this type. + Named_object* + add_method_declaration(const std::string& name, Function_type*, + source_location); + + protected: + int + do_traverse(Traverse* traverse); + + bool + do_has_pointer() const + { return this->real_type()->has_pointer(); } + + unsigned int + do_hash_for_method(Gogo* gogo) const + { return this->real_type()->hash_for_method(gogo); } + + bool + do_check_make_expression(Expression_list* args, source_location location) + { return this->base()->check_make_expression(args, location); } + + tree + do_get_tree(Gogo* gogo); + + tree + do_get_init_tree(Gogo* gogo, tree type_tree, bool is_clear) + { return this->base()->get_typed_init_tree(gogo, type_tree, is_clear); } + + tree + do_make_expression_tree(Translate_context* context, Expression_list* args, + source_location location) + { return this->base()->make_expression_tree(context, args, location); } + + Expression* + do_type_descriptor(Gogo*, Named_type*); + + void + do_reflection(Gogo*, std::string*) const; + + void + do_mangled_name(Gogo*, std::string* ret) const; + + void + do_export(Export*) const; + + private: + // Issue a warning about a use of an undefined type. + void + warn() const; + + // The type declaration. + Named_object* named_object_; + // Whether we have issued a warning about this type. + mutable bool warned_; +}; + +// The Type_context struct describes what we expect for the type of an +// expression. + +struct Type_context +{ + // The exact type we expect, if known. This may be NULL. + Type* type; + // Whether an abstract type is permitted. + bool may_be_abstract; + + // Constructors. + Type_context() + : type(NULL), may_be_abstract(false) + { } + + Type_context(Type* a_type, bool a_may_be_abstract) + : type(a_type), may_be_abstract(a_may_be_abstract) + { } +}; + +#endif // !defined(GO_TYPES_H) diff --git a/gcc/go/gofrontend/unsafe.cc b/gcc/go/gofrontend/unsafe.cc new file mode 100644 index 000000000..9d51b4d94 --- /dev/null +++ b/gcc/go/gofrontend/unsafe.cc @@ -0,0 +1,146 @@ +// unsafe.cc -- Go frontend builtin unsafe package. + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#include "go-system.h" + +#include "go-c.h" +#include "types.h" +#include "gogo.h" + +// Set up the builtin unsafe package. This should probably be driven +// by a table. + +void +Gogo::import_unsafe(const std::string& local_name, bool is_local_name_exported, + source_location location) +{ + location_t bloc = BUILTINS_LOCATION; + + bool add_to_globals; + Package* package = this->add_imported_package("unsafe", local_name, + is_local_name_exported, + "libgo_unsafe", + location, &add_to_globals); + + if (package == NULL) + { + gcc_assert(saw_errors()); + return; + } + + package->set_is_imported(); + + Bindings* bindings = package->bindings(); + + // The type may have already been created by an import. + Named_object* no = package->bindings()->lookup("Pointer"); + if (no == NULL) + { + Type* type = Type::make_pointer_type(Type::make_void_type()); + no = bindings->add_type("Pointer", package, type, UNKNOWN_LOCATION); + } + else + { + gcc_assert(no->package() == package); + gcc_assert(no->is_type()); + gcc_assert(no->type_value()->is_unsafe_pointer_type()); + no->type_value()->set_is_visible(); + } + Named_type* pointer_type = no->type_value(); + if (add_to_globals) + this->add_named_type(pointer_type); + + Type* int_type = this->lookup_global("int")->type_value(); + + // Sizeof. + Typed_identifier_list* results = new Typed_identifier_list; + results->push_back(Typed_identifier("", int_type, bloc)); + Function_type* fntype = Type::make_function_type(NULL, NULL, results, bloc); + fntype->set_is_builtin(); + no = bindings->add_function_declaration("Sizeof", package, fntype, bloc); + if (add_to_globals) + this->add_named_object(no); + + // Offsetof. + results = new Typed_identifier_list; + results->push_back(Typed_identifier("", int_type, bloc)); + fntype = Type::make_function_type(NULL, NULL, results, bloc); + fntype->set_is_varargs(); + fntype->set_is_builtin(); + no = bindings->add_function_declaration("Offsetof", package, fntype, bloc); + if (add_to_globals) + this->add_named_object(no); + + // Alignof. + results = new Typed_identifier_list; + results->push_back(Typed_identifier("", int_type, bloc)); + fntype = Type::make_function_type(NULL, NULL, results, bloc); + fntype->set_is_varargs(); + fntype->set_is_builtin(); + no = bindings->add_function_declaration("Alignof", package, fntype, bloc); + if (add_to_globals) + this->add_named_object(no); + + // Typeof. + Type* empty_interface = Type::make_interface_type(NULL, bloc); + Typed_identifier_list* parameters = new Typed_identifier_list; + parameters->push_back(Typed_identifier("i", empty_interface, bloc)); + results = new Typed_identifier_list; + results->push_back(Typed_identifier("", empty_interface, bloc)); + fntype = Type::make_function_type(NULL, parameters, results, bloc); + no = bindings->add_function_declaration("Typeof", package, fntype, bloc); + if (add_to_globals) + this->add_named_object(no); + + // Reflect. + parameters = new Typed_identifier_list; + parameters->push_back(Typed_identifier("it", empty_interface, bloc)); + results = new Typed_identifier_list; + results->push_back(Typed_identifier("", empty_interface, bloc)); + results->push_back(Typed_identifier("", pointer_type, bloc)); + fntype = Type::make_function_type(NULL, parameters, results, bloc); + no = bindings->add_function_declaration("Reflect", package, fntype, bloc); + if (add_to_globals) + this->add_named_object(no); + + // Unreflect. + parameters = new Typed_identifier_list; + parameters->push_back(Typed_identifier("typ", empty_interface, bloc)); + parameters->push_back(Typed_identifier("addr", pointer_type, bloc)); + results = new Typed_identifier_list; + results->push_back(Typed_identifier("", empty_interface, bloc)); + fntype = Type::make_function_type(NULL, parameters, results, bloc); + no = bindings->add_function_declaration("Unreflect", package, fntype, bloc); + if (add_to_globals) + this->add_named_object(no); + + // New. + parameters = new Typed_identifier_list; + parameters->push_back(Typed_identifier("typ", empty_interface, bloc)); + results = new Typed_identifier_list; + results->push_back(Typed_identifier("", pointer_type, bloc)); + fntype = Type::make_function_type(NULL, parameters, results, bloc); + no = bindings->add_function_declaration("New", package, fntype, bloc); + if (add_to_globals) + this->add_named_object(no); + + // NewArray. + parameters = new Typed_identifier_list; + parameters->push_back(Typed_identifier("typ", empty_interface, bloc)); + parameters->push_back(Typed_identifier("n", int_type, bloc)); + results = new Typed_identifier_list; + results->push_back(Typed_identifier("", pointer_type, bloc)); + fntype = Type::make_function_type(NULL, parameters, results, bloc); + no = bindings->add_function_declaration("NewArray", package, fntype, bloc); + if (add_to_globals) + this->add_named_object(no); + + if (!this->imported_unsafe_) + { + go_imported_unsafe(); + this->imported_unsafe_ = true; + } +} |