From 554fd8c5195424bdbcabf5de30fdc183aba391bd Mon Sep 17 00:00:00 2001 From: upstream source tree Date: Sun, 15 Mar 2015 20:14:05 -0400 Subject: obtained gcc-4.6.4.tar.bz2 from upstream website; verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository. --- gcc/tree-ssa-operands.c | 1357 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1357 insertions(+) create mode 100644 gcc/tree-ssa-operands.c (limited to 'gcc/tree-ssa-operands.c') diff --git a/gcc/tree-ssa-operands.c b/gcc/tree-ssa-operands.c new file mode 100644 index 000000000..d05f81491 --- /dev/null +++ b/gcc/tree-ssa-operands.c @@ -0,0 +1,1357 @@ +/* SSA operands management for trees. + Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 + Free Software Foundation, Inc. + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 3, or (at your option) +any later version. + +GCC is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the file COPYING3. If not see +. */ + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "tm.h" +#include "tree.h" +#include "flags.h" +#include "function.h" +#include "tree-pretty-print.h" +#include "gimple-pretty-print.h" +#include "tree-flow.h" +#include "tree-inline.h" +#include "tree-pass.h" +#include "ggc.h" +#include "timevar.h" +#include "langhooks.h" +#include "ipa-reference.h" + +/* This file contains the code required to manage the operands cache of the + SSA optimizer. For every stmt, we maintain an operand cache in the stmt + annotation. This cache contains operands that will be of interest to + optimizers and other passes wishing to manipulate the IL. + + The operand type are broken up into REAL and VIRTUAL operands. The real + operands are represented as pointers into the stmt's operand tree. Thus + any manipulation of the real operands will be reflected in the actual tree. + Virtual operands are represented solely in the cache, although the base + variable for the SSA_NAME may, or may not occur in the stmt's tree. + Manipulation of the virtual operands will not be reflected in the stmt tree. + + The routines in this file are concerned with creating this operand cache + from a stmt tree. + + The operand tree is the parsed by the various get_* routines which look + through the stmt tree for the occurrence of operands which may be of + interest, and calls are made to the append_* routines whenever one is + found. There are 4 of these routines, each representing one of the + 4 types of operands. Defs, Uses, Virtual Uses, and Virtual May Defs. + + The append_* routines check for duplication, and simply keep a list of + unique objects for each operand type in the build_* extendable vectors. + + Once the stmt tree is completely parsed, the finalize_ssa_operands() + routine is called, which proceeds to perform the finalization routine + on each of the 4 operand vectors which have been built up. + + If the stmt had a previous operand cache, the finalization routines + attempt to match up the new operands with the old ones. If it's a perfect + match, the old vector is simply reused. If it isn't a perfect match, then + a new vector is created and the new operands are placed there. For + virtual operands, if the previous cache had SSA_NAME version of a + variable, and that same variable occurs in the same operands cache, then + the new cache vector will also get the same SSA_NAME. + + i.e., if a stmt had a VUSE of 'a_5', and 'a' occurs in the new + operand vector for VUSE, then the new vector will also be modified + such that it contains 'a_5' rather than 'a'. */ + +/* Structure storing statistics on how many call clobbers we have, and + how many where avoided. */ + +static struct +{ + /* Number of call-clobbered ops we attempt to add to calls in + add_call_clobbered_mem_symbols. */ + unsigned int clobbered_vars; + + /* Number of write-clobbers (VDEFs) avoided by using + not_written information. */ + unsigned int static_write_clobbers_avoided; + + /* Number of reads (VUSEs) avoided by using not_read information. */ + unsigned int static_read_clobbers_avoided; + + /* Number of write-clobbers avoided because the variable can't escape to + this call. */ + unsigned int unescapable_clobbers_avoided; + + /* Number of read-only uses we attempt to add to calls in + add_call_read_mem_symbols. */ + unsigned int readonly_clobbers; + + /* Number of read-only uses we avoid using not_read information. */ + unsigned int static_readonly_clobbers_avoided; +} clobber_stats; + + +/* Flags to describe operand properties in helpers. */ + +/* By default, operands are loaded. */ +#define opf_use 0 + +/* Operand is the target of an assignment expression or a + call-clobbered variable. */ +#define opf_def (1 << 0) + +/* No virtual operands should be created in the expression. This is used + when traversing ADDR_EXPR nodes which have different semantics than + other expressions. Inside an ADDR_EXPR node, the only operands that we + need to consider are indices into arrays. For instance, &a.b[i] should + generate a USE of 'i' but it should not generate a VUSE for 'a' nor a + VUSE for 'b'. */ +#define opf_no_vops (1 << 1) + +/* Operand is an implicit reference. This is used to distinguish + explicit assignments in the form of MODIFY_EXPR from + clobbering sites like function calls or ASM_EXPRs. */ +#define opf_implicit (1 << 2) + +/* Operand is in a place where address-taken does not imply addressable. */ +#define opf_non_addressable (1 << 3) + +/* Operand is in a place where opf_non_addressable does not apply. */ +#define opf_not_non_addressable (1 << 4) + +/* Array for building all the def operands. */ +static VEC(tree,heap) *build_defs; + +/* Array for building all the use operands. */ +static VEC(tree,heap) *build_uses; + +/* The built VDEF operand. */ +static tree build_vdef; + +/* The built VUSE operand. */ +static tree build_vuse; + +/* Bitmap obstack for our datastructures that needs to survive across + compilations of multiple functions. */ +static bitmap_obstack operands_bitmap_obstack; + +static void get_expr_operands (gimple, tree *, int); + +/* Number of functions with initialized ssa_operands. */ +static int n_initialized = 0; + +/* Return the DECL_UID of the base variable of T. */ + +static inline unsigned +get_name_decl (const_tree t) +{ + if (TREE_CODE (t) != SSA_NAME) + return DECL_UID (t); + else + return DECL_UID (SSA_NAME_VAR (t)); +} + + +/* Return true if the SSA operands cache is active. */ + +bool +ssa_operands_active (void) +{ + /* This function may be invoked from contexts where CFUN is NULL + (IPA passes), return false for now. FIXME: operands may be + active in each individual function, maybe this function should + take CFUN as a parameter. */ + if (cfun == NULL) + return false; + + return cfun->gimple_df && gimple_ssa_operands (cfun)->ops_active; +} + + +/* Create the VOP variable, an artificial global variable to act as a + representative of all of the virtual operands FUD chain. */ + +static void +create_vop_var (void) +{ + tree global_var; + + gcc_assert (cfun->gimple_df->vop == NULL_TREE); + + global_var = build_decl (BUILTINS_LOCATION, VAR_DECL, + get_identifier (".MEM"), + void_type_node); + DECL_ARTIFICIAL (global_var) = 1; + TREE_READONLY (global_var) = 0; + DECL_EXTERNAL (global_var) = 1; + TREE_STATIC (global_var) = 1; + TREE_USED (global_var) = 1; + DECL_CONTEXT (global_var) = NULL_TREE; + TREE_THIS_VOLATILE (global_var) = 0; + TREE_ADDRESSABLE (global_var) = 0; + + create_var_ann (global_var); + add_referenced_var (global_var); + cfun->gimple_df->vop = global_var; +} + +/* These are the sizes of the operand memory buffer in bytes which gets + allocated each time more operands space is required. The final value is + the amount that is allocated every time after that. + In 1k we can fit 25 use operands (or 63 def operands) on a host with + 8 byte pointers, that would be 10 statements each with 1 def and 2 + uses. */ + +#define OP_SIZE_INIT 0 +#define OP_SIZE_1 (1024 - sizeof (void *)) +#define OP_SIZE_2 (1024 * 4 - sizeof (void *)) +#define OP_SIZE_3 (1024 * 16 - sizeof (void *)) + +/* Initialize the operand cache routines. */ + +void +init_ssa_operands (void) +{ + if (!n_initialized++) + { + build_defs = VEC_alloc (tree, heap, 5); + build_uses = VEC_alloc (tree, heap, 10); + build_vuse = NULL_TREE; + build_vdef = NULL_TREE; + bitmap_obstack_initialize (&operands_bitmap_obstack); + } + + gcc_assert (gimple_ssa_operands (cfun)->operand_memory == NULL); + gimple_ssa_operands (cfun)->operand_memory_index + = gimple_ssa_operands (cfun)->ssa_operand_mem_size; + gimple_ssa_operands (cfun)->ops_active = true; + memset (&clobber_stats, 0, sizeof (clobber_stats)); + gimple_ssa_operands (cfun)->ssa_operand_mem_size = OP_SIZE_INIT; + create_vop_var (); +} + + +/* Dispose of anything required by the operand routines. */ + +void +fini_ssa_operands (void) +{ + struct ssa_operand_memory_d *ptr; + + if (!--n_initialized) + { + VEC_free (tree, heap, build_defs); + VEC_free (tree, heap, build_uses); + build_vdef = NULL_TREE; + build_vuse = NULL_TREE; + } + + gimple_ssa_operands (cfun)->free_defs = NULL; + gimple_ssa_operands (cfun)->free_uses = NULL; + + while ((ptr = gimple_ssa_operands (cfun)->operand_memory) != NULL) + { + gimple_ssa_operands (cfun)->operand_memory + = gimple_ssa_operands (cfun)->operand_memory->next; + ggc_free (ptr); + } + + gimple_ssa_operands (cfun)->ops_active = false; + + if (!n_initialized) + bitmap_obstack_release (&operands_bitmap_obstack); + + cfun->gimple_df->vop = NULL_TREE; + + if (dump_file && (dump_flags & TDF_STATS)) + { + fprintf (dump_file, "Original clobbered vars: %d\n", + clobber_stats.clobbered_vars); + fprintf (dump_file, "Static write clobbers avoided: %d\n", + clobber_stats.static_write_clobbers_avoided); + fprintf (dump_file, "Static read clobbers avoided: %d\n", + clobber_stats.static_read_clobbers_avoided); + fprintf (dump_file, "Unescapable clobbers avoided: %d\n", + clobber_stats.unescapable_clobbers_avoided); + fprintf (dump_file, "Original read-only clobbers: %d\n", + clobber_stats.readonly_clobbers); + fprintf (dump_file, "Static read-only clobbers avoided: %d\n", + clobber_stats.static_readonly_clobbers_avoided); + } +} + + +/* Return memory for an operand of size SIZE. */ + +static inline void * +ssa_operand_alloc (unsigned size) +{ + char *ptr; + + gcc_assert (size == sizeof (struct use_optype_d) + || size == sizeof (struct def_optype_d)); + + if (gimple_ssa_operands (cfun)->operand_memory_index + size + >= gimple_ssa_operands (cfun)->ssa_operand_mem_size) + { + struct ssa_operand_memory_d *ptr; + + switch (gimple_ssa_operands (cfun)->ssa_operand_mem_size) + { + case OP_SIZE_INIT: + gimple_ssa_operands (cfun)->ssa_operand_mem_size = OP_SIZE_1; + break; + case OP_SIZE_1: + gimple_ssa_operands (cfun)->ssa_operand_mem_size = OP_SIZE_2; + break; + case OP_SIZE_2: + case OP_SIZE_3: + gimple_ssa_operands (cfun)->ssa_operand_mem_size = OP_SIZE_3; + break; + default: + gcc_unreachable (); + } + + + ptr = ggc_alloc_ssa_operand_memory_d (sizeof (void *) + + gimple_ssa_operands (cfun)->ssa_operand_mem_size); + + ptr->next = gimple_ssa_operands (cfun)->operand_memory; + gimple_ssa_operands (cfun)->operand_memory = ptr; + gimple_ssa_operands (cfun)->operand_memory_index = 0; + } + + ptr = &(gimple_ssa_operands (cfun)->operand_memory + ->mem[gimple_ssa_operands (cfun)->operand_memory_index]); + gimple_ssa_operands (cfun)->operand_memory_index += size; + return ptr; +} + + +/* Allocate a DEF operand. */ + +static inline struct def_optype_d * +alloc_def (void) +{ + struct def_optype_d *ret; + if (gimple_ssa_operands (cfun)->free_defs) + { + ret = gimple_ssa_operands (cfun)->free_defs; + gimple_ssa_operands (cfun)->free_defs + = gimple_ssa_operands (cfun)->free_defs->next; + } + else + ret = (struct def_optype_d *) + ssa_operand_alloc (sizeof (struct def_optype_d)); + return ret; +} + + +/* Allocate a USE operand. */ + +static inline struct use_optype_d * +alloc_use (void) +{ + struct use_optype_d *ret; + if (gimple_ssa_operands (cfun)->free_uses) + { + ret = gimple_ssa_operands (cfun)->free_uses; + gimple_ssa_operands (cfun)->free_uses + = gimple_ssa_operands (cfun)->free_uses->next; + } + else + ret = (struct use_optype_d *) + ssa_operand_alloc (sizeof (struct use_optype_d)); + return ret; +} + + +/* Adds OP to the list of defs after LAST. */ + +static inline def_optype_p +add_def_op (tree *op, def_optype_p last) +{ + def_optype_p new_def; + + new_def = alloc_def (); + DEF_OP_PTR (new_def) = op; + last->next = new_def; + new_def->next = NULL; + return new_def; +} + + +/* Adds OP to the list of uses of statement STMT after LAST. */ + +static inline use_optype_p +add_use_op (gimple stmt, tree *op, use_optype_p last) +{ + use_optype_p new_use; + + new_use = alloc_use (); + USE_OP_PTR (new_use)->use = op; + link_imm_use_stmt (USE_OP_PTR (new_use), *op, stmt); + last->next = new_use; + new_use->next = NULL; + return new_use; +} + + + +/* Takes elements from build_defs and turns them into def operands of STMT. + TODO -- Make build_defs VEC of tree *. */ + +static inline void +finalize_ssa_defs (gimple stmt) +{ + unsigned new_i; + struct def_optype_d new_list; + def_optype_p old_ops, last; + unsigned int num = VEC_length (tree, build_defs); + + /* There should only be a single real definition per assignment. */ + gcc_assert ((stmt && gimple_code (stmt) != GIMPLE_ASSIGN) || num <= 1); + + /* Pre-pend the vdef we may have built. */ + if (build_vdef != NULL_TREE) + { + tree oldvdef = gimple_vdef (stmt); + if (oldvdef + && TREE_CODE (oldvdef) == SSA_NAME) + oldvdef = SSA_NAME_VAR (oldvdef); + if (oldvdef != build_vdef) + gimple_set_vdef (stmt, build_vdef); + VEC_safe_insert (tree, heap, build_defs, 0, (tree)gimple_vdef_ptr (stmt)); + ++num; + } + + new_list.next = NULL; + last = &new_list; + + old_ops = gimple_def_ops (stmt); + + new_i = 0; + + /* Clear and unlink a no longer necessary VDEF. */ + if (build_vdef == NULL_TREE + && gimple_vdef (stmt) != NULL_TREE) + { + if (TREE_CODE (gimple_vdef (stmt)) == SSA_NAME) + { + unlink_stmt_vdef (stmt); + release_ssa_name (gimple_vdef (stmt)); + } + gimple_set_vdef (stmt, NULL_TREE); + } + + /* If we have a non-SSA_NAME VDEF, mark it for renaming. */ + if (gimple_vdef (stmt) + && TREE_CODE (gimple_vdef (stmt)) != SSA_NAME) + mark_sym_for_renaming (gimple_vdef (stmt)); + + /* Check for the common case of 1 def that hasn't changed. */ + if (old_ops && old_ops->next == NULL && num == 1 + && (tree *) VEC_index (tree, build_defs, 0) == DEF_OP_PTR (old_ops)) + return; + + /* If there is anything in the old list, free it. */ + if (old_ops) + { + old_ops->next = gimple_ssa_operands (cfun)->free_defs; + gimple_ssa_operands (cfun)->free_defs = old_ops; + } + + /* If there is anything remaining in the build_defs list, simply emit it. */ + for ( ; new_i < num; new_i++) + last = add_def_op ((tree *) VEC_index (tree, build_defs, new_i), last); + + /* Now set the stmt's operands. */ + gimple_set_def_ops (stmt, new_list.next); +} + + +/* Takes elements from build_uses and turns them into use operands of STMT. + TODO -- Make build_uses VEC of tree *. */ + +static inline void +finalize_ssa_uses (gimple stmt) +{ + unsigned new_i; + struct use_optype_d new_list; + use_optype_p old_ops, ptr, last; + + /* Pre-pend the VUSE we may have built. */ + if (build_vuse != NULL_TREE) + { + tree oldvuse = gimple_vuse (stmt); + if (oldvuse + && TREE_CODE (oldvuse) == SSA_NAME) + oldvuse = SSA_NAME_VAR (oldvuse); + if (oldvuse != (build_vuse != NULL_TREE + ? build_vuse : build_vdef)) + gimple_set_vuse (stmt, NULL_TREE); + VEC_safe_insert (tree, heap, build_uses, 0, (tree)gimple_vuse_ptr (stmt)); + } + + new_list.next = NULL; + last = &new_list; + + old_ops = gimple_use_ops (stmt); + + /* Clear a no longer necessary VUSE. */ + if (build_vuse == NULL_TREE + && gimple_vuse (stmt) != NULL_TREE) + gimple_set_vuse (stmt, NULL_TREE); + + /* If there is anything in the old list, free it. */ + if (old_ops) + { + for (ptr = old_ops; ptr; ptr = ptr->next) + delink_imm_use (USE_OP_PTR (ptr)); + old_ops->next = gimple_ssa_operands (cfun)->free_uses; + gimple_ssa_operands (cfun)->free_uses = old_ops; + } + + /* If we added a VUSE, make sure to set the operand if it is not already + present and mark it for renaming. */ + if (build_vuse != NULL_TREE + && gimple_vuse (stmt) == NULL_TREE) + { + gimple_set_vuse (stmt, gimple_vop (cfun)); + mark_sym_for_renaming (gimple_vop (cfun)); + } + + /* Now create nodes for all the new nodes. */ + for (new_i = 0; new_i < VEC_length (tree, build_uses); new_i++) + last = add_use_op (stmt, + (tree *) VEC_index (tree, build_uses, new_i), + last); + + /* Now set the stmt's operands. */ + gimple_set_use_ops (stmt, new_list.next); +} + + +/* Clear the in_list bits and empty the build array for VDEFs and + VUSEs. */ + +static inline void +cleanup_build_arrays (void) +{ + build_vdef = NULL_TREE; + build_vuse = NULL_TREE; + VEC_truncate (tree, build_defs, 0); + VEC_truncate (tree, build_uses, 0); +} + + +/* Finalize all the build vectors, fill the new ones into INFO. */ + +static inline void +finalize_ssa_stmt_operands (gimple stmt) +{ + finalize_ssa_defs (stmt); + finalize_ssa_uses (stmt); + cleanup_build_arrays (); +} + + +/* Start the process of building up operands vectors in INFO. */ + +static inline void +start_ssa_stmt_operands (void) +{ + gcc_assert (VEC_length (tree, build_defs) == 0); + gcc_assert (VEC_length (tree, build_uses) == 0); + gcc_assert (build_vuse == NULL_TREE); + gcc_assert (build_vdef == NULL_TREE); +} + + +/* Add DEF_P to the list of pointers to operands. */ + +static inline void +append_def (tree *def_p) +{ + VEC_safe_push (tree, heap, build_defs, (tree) def_p); +} + + +/* Add USE_P to the list of pointers to operands. */ + +static inline void +append_use (tree *use_p) +{ + VEC_safe_push (tree, heap, build_uses, (tree) use_p); +} + + +/* Add VAR to the set of variables that require a VDEF operator. */ + +static inline void +append_vdef (tree var) +{ + if (!optimize) + return; + + gcc_assert ((build_vdef == NULL_TREE + || build_vdef == var) + && (build_vuse == NULL_TREE + || build_vuse == var)); + + build_vdef = var; + build_vuse = var; +} + + +/* Add VAR to the set of variables that require a VUSE operator. */ + +static inline void +append_vuse (tree var) +{ + if (!optimize) + return; + + gcc_assert (build_vuse == NULL_TREE + || build_vuse == var); + + build_vuse = var; +} + +/* Add virtual operands for STMT. FLAGS is as in get_expr_operands. */ + +static void +add_virtual_operand (gimple stmt ATTRIBUTE_UNUSED, int flags) +{ + /* Add virtual operands to the stmt, unless the caller has specifically + requested not to do that (used when adding operands inside an + ADDR_EXPR expression). */ + if (flags & opf_no_vops) + return; + + gcc_assert (!is_gimple_debug (stmt)); + + if (flags & opf_def) + append_vdef (gimple_vop (cfun)); + else + append_vuse (gimple_vop (cfun)); +} + + +/* Add *VAR_P to the appropriate operand array for statement STMT. + FLAGS is as in get_expr_operands. If *VAR_P is a GIMPLE register, + it will be added to the statement's real operands, otherwise it is + added to virtual operands. */ + +static void +add_stmt_operand (tree *var_p, gimple stmt, int flags) +{ + tree var, sym; + + gcc_assert (SSA_VAR_P (*var_p)); + + var = *var_p; + sym = (TREE_CODE (var) == SSA_NAME ? SSA_NAME_VAR (var) : var); + + /* Mark statements with volatile operands. */ + if (TREE_THIS_VOLATILE (sym)) + gimple_set_has_volatile_ops (stmt, true); + + if (is_gimple_reg (sym)) + { + /* The variable is a GIMPLE register. Add it to real operands. */ + if (flags & opf_def) + append_def (var_p); + else + append_use (var_p); + } + else + add_virtual_operand (stmt, flags); +} + +/* Mark the base address of REF as having its address taken. + REF may be a single variable whose address has been taken or any + other valid GIMPLE memory reference (structure reference, array, + etc). */ + +static void +mark_address_taken (tree ref) +{ + tree var; + + /* Note that it is *NOT OKAY* to use the target of a COMPONENT_REF + as the only thing we take the address of. If VAR is a structure, + taking the address of a field means that the whole structure may + be referenced using pointer arithmetic. See PR 21407 and the + ensuing mailing list discussion. */ + var = get_base_address (ref); + if (var) + { + if (DECL_P (var)) + TREE_ADDRESSABLE (var) = 1; + else if (TREE_CODE (var) == MEM_REF + && TREE_CODE (TREE_OPERAND (var, 0)) == ADDR_EXPR + && DECL_P (TREE_OPERAND (TREE_OPERAND (var, 0), 0))) + TREE_ADDRESSABLE (TREE_OPERAND (TREE_OPERAND (var, 0), 0)) = 1; + } +} + + +/* A subroutine of get_expr_operands to handle MEM_REF. + + STMT is the statement being processed, EXPR is the MEM_REF + that got us here. + + FLAGS is as in get_expr_operands. + + RECURSE_ON_BASE should be set to true if we want to continue + calling get_expr_operands on the base pointer, and false if + something else will do it for us. */ + +static void +get_indirect_ref_operands (gimple stmt, tree expr, int flags, + bool recurse_on_base) +{ + tree *pptr = &TREE_OPERAND (expr, 0); + + if (TREE_THIS_VOLATILE (expr)) + gimple_set_has_volatile_ops (stmt, true); + + /* Add the VOP. */ + add_virtual_operand (stmt, flags); + + /* If requested, add a USE operand for the base pointer. */ + if (recurse_on_base) + get_expr_operands (stmt, pptr, + opf_non_addressable | opf_use + | (flags & (opf_no_vops|opf_not_non_addressable))); +} + + +/* A subroutine of get_expr_operands to handle TARGET_MEM_REF. */ + +static void +get_tmr_operands (gimple stmt, tree expr, int flags) +{ + if (TREE_THIS_VOLATILE (expr)) + gimple_set_has_volatile_ops (stmt, true); + + /* First record the real operands. */ + get_expr_operands (stmt, &TMR_BASE (expr), opf_use | (flags & opf_no_vops)); + get_expr_operands (stmt, &TMR_INDEX (expr), opf_use | (flags & opf_no_vops)); + get_expr_operands (stmt, &TMR_INDEX2 (expr), opf_use | (flags & opf_no_vops)); + + add_virtual_operand (stmt, flags); +} + + +/* If STMT is a call that may clobber globals and other symbols that + escape, add them to the VDEF/VUSE lists for it. */ + +static void +maybe_add_call_vops (gimple stmt) +{ + int call_flags = gimple_call_flags (stmt); + + /* If aliases have been computed already, add VDEF or VUSE + operands for all the symbols that have been found to be + call-clobbered. */ + if (!(call_flags & ECF_NOVOPS)) + { + /* A 'pure' or a 'const' function never call-clobbers anything. + A 'noreturn' function might, but since we don't return anyway + there is no point in recording that. */ + if (!(call_flags & (ECF_PURE | ECF_CONST | ECF_NORETURN))) + add_virtual_operand (stmt, opf_def); + else if (!(call_flags & ECF_CONST)) + add_virtual_operand (stmt, opf_use); + } +} + + +/* Scan operands in the ASM_EXPR stmt referred to in INFO. */ + +static void +get_asm_expr_operands (gimple stmt) +{ + size_t i, noutputs; + const char **oconstraints; + const char *constraint; + bool allows_mem, allows_reg, is_inout; + + noutputs = gimple_asm_noutputs (stmt); + oconstraints = (const char **) alloca ((noutputs) * sizeof (const char *)); + + /* Gather all output operands. */ + for (i = 0; i < gimple_asm_noutputs (stmt); i++) + { + tree link = gimple_asm_output_op (stmt, i); + constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); + oconstraints[i] = constraint; + parse_output_constraint (&constraint, i, 0, 0, &allows_mem, + &allows_reg, &is_inout); + + /* This should have been split in gimplify_asm_expr. */ + gcc_assert (!allows_reg || !is_inout); + + /* Memory operands are addressable. Note that STMT needs the + address of this operand. */ + if (!allows_reg && allows_mem) + mark_address_taken (TREE_VALUE (link)); + + get_expr_operands (stmt, &TREE_VALUE (link), opf_def | opf_not_non_addressable); + } + + /* Gather all input operands. */ + for (i = 0; i < gimple_asm_ninputs (stmt); i++) + { + tree link = gimple_asm_input_op (stmt, i); + constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); + parse_input_constraint (&constraint, 0, 0, noutputs, 0, oconstraints, + &allows_mem, &allows_reg); + + /* Memory operands are addressable. Note that STMT needs the + address of this operand. */ + if (!allows_reg && allows_mem) + mark_address_taken (TREE_VALUE (link)); + + get_expr_operands (stmt, &TREE_VALUE (link), opf_not_non_addressable); + } + + /* Clobber all memory and addressable symbols for asm ("" : : : "memory"); */ + for (i = 0; i < gimple_asm_nclobbers (stmt); i++) + { + tree link = gimple_asm_clobber_op (stmt, i); + if (strcmp (TREE_STRING_POINTER (TREE_VALUE (link)), "memory") == 0) + { + add_virtual_operand (stmt, opf_def); + break; + } + } +} + + +/* Recursively scan the expression pointed to by EXPR_P in statement + STMT. FLAGS is one of the OPF_* constants modifying how to + interpret the operands found. */ + +static void +get_expr_operands (gimple stmt, tree *expr_p, int flags) +{ + enum tree_code code; + enum tree_code_class codeclass; + tree expr = *expr_p; + int uflags = opf_use; + + if (expr == NULL) + return; + + if (is_gimple_debug (stmt)) + uflags |= (flags & opf_no_vops); + + code = TREE_CODE (expr); + codeclass = TREE_CODE_CLASS (code); + + switch (code) + { + case ADDR_EXPR: + /* Taking the address of a variable does not represent a + reference to it, but the fact that the statement takes its + address will be of interest to some passes (e.g. alias + resolution). */ + if ((!(flags & opf_non_addressable) + || (flags & opf_not_non_addressable)) + && !is_gimple_debug (stmt)) + mark_address_taken (TREE_OPERAND (expr, 0)); + + /* If the address is invariant, there may be no interesting + variable references inside. */ + if (is_gimple_min_invariant (expr)) + return; + + /* Otherwise, there may be variables referenced inside but there + should be no VUSEs created, since the referenced objects are + not really accessed. The only operands that we should find + here are ARRAY_REF indices which will always be real operands + (GIMPLE does not allow non-registers as array indices). */ + flags |= opf_no_vops; + get_expr_operands (stmt, &TREE_OPERAND (expr, 0), + flags | opf_not_non_addressable); + return; + + case SSA_NAME: + add_stmt_operand (expr_p, stmt, flags); + return; + + case VAR_DECL: + case PARM_DECL: + case RESULT_DECL: + add_stmt_operand (expr_p, stmt, flags); + return; + + case DEBUG_EXPR_DECL: + gcc_assert (gimple_debug_bind_p (stmt)); + return; + + case MEM_REF: + get_indirect_ref_operands (stmt, expr, flags, true); + return; + + case TARGET_MEM_REF: + get_tmr_operands (stmt, expr, flags); + return; + + case ARRAY_REF: + case ARRAY_RANGE_REF: + case COMPONENT_REF: + case REALPART_EXPR: + case IMAGPART_EXPR: + { + if (TREE_THIS_VOLATILE (expr)) + gimple_set_has_volatile_ops (stmt, true); + + get_expr_operands (stmt, &TREE_OPERAND (expr, 0), flags); + + if (code == COMPONENT_REF) + { + if (TREE_THIS_VOLATILE (TREE_OPERAND (expr, 1))) + gimple_set_has_volatile_ops (stmt, true); + get_expr_operands (stmt, &TREE_OPERAND (expr, 2), uflags); + } + else if (code == ARRAY_REF || code == ARRAY_RANGE_REF) + { + get_expr_operands (stmt, &TREE_OPERAND (expr, 1), uflags); + get_expr_operands (stmt, &TREE_OPERAND (expr, 2), uflags); + get_expr_operands (stmt, &TREE_OPERAND (expr, 3), uflags); + } + + return; + } + + case WITH_SIZE_EXPR: + /* WITH_SIZE_EXPR is a pass-through reference to its first argument, + and an rvalue reference to its second argument. */ + get_expr_operands (stmt, &TREE_OPERAND (expr, 1), uflags); + get_expr_operands (stmt, &TREE_OPERAND (expr, 0), flags); + return; + + case COND_EXPR: + case VEC_COND_EXPR: + get_expr_operands (stmt, &TREE_OPERAND (expr, 0), uflags); + get_expr_operands (stmt, &TREE_OPERAND (expr, 1), uflags); + get_expr_operands (stmt, &TREE_OPERAND (expr, 2), uflags); + return; + + case CONSTRUCTOR: + { + /* General aggregate CONSTRUCTORs have been decomposed, but they + are still in use as the COMPLEX_EXPR equivalent for vectors. */ + constructor_elt *ce; + unsigned HOST_WIDE_INT idx; + + for (idx = 0; + VEC_iterate (constructor_elt, CONSTRUCTOR_ELTS (expr), idx, ce); + idx++) + get_expr_operands (stmt, &ce->value, uflags); + + return; + } + + case BIT_FIELD_REF: + if (TREE_THIS_VOLATILE (expr)) + gimple_set_has_volatile_ops (stmt, true); + /* FALLTHRU */ + + case TRUTH_NOT_EXPR: + case VIEW_CONVERT_EXPR: + do_unary: + get_expr_operands (stmt, &TREE_OPERAND (expr, 0), flags); + return; + + case TRUTH_AND_EXPR: + case TRUTH_OR_EXPR: + case TRUTH_XOR_EXPR: + case COMPOUND_EXPR: + case OBJ_TYPE_REF: + case ASSERT_EXPR: + do_binary: + { + get_expr_operands (stmt, &TREE_OPERAND (expr, 0), flags); + get_expr_operands (stmt, &TREE_OPERAND (expr, 1), flags); + return; + } + + case DOT_PROD_EXPR: + case REALIGN_LOAD_EXPR: + case WIDEN_MULT_PLUS_EXPR: + case WIDEN_MULT_MINUS_EXPR: + case FMA_EXPR: + { + get_expr_operands (stmt, &TREE_OPERAND (expr, 0), flags); + get_expr_operands (stmt, &TREE_OPERAND (expr, 1), flags); + get_expr_operands (stmt, &TREE_OPERAND (expr, 2), flags); + return; + } + + case FUNCTION_DECL: + case LABEL_DECL: + case CONST_DECL: + case CASE_LABEL_EXPR: + /* Expressions that make no memory references. */ + return; + + default: + if (codeclass == tcc_unary) + goto do_unary; + if (codeclass == tcc_binary || codeclass == tcc_comparison) + goto do_binary; + if (codeclass == tcc_constant || codeclass == tcc_type) + return; + } + + /* If we get here, something has gone wrong. */ +#ifdef ENABLE_CHECKING + fprintf (stderr, "unhandled expression in get_expr_operands():\n"); + debug_tree (expr); + fputs ("\n", stderr); +#endif + gcc_unreachable (); +} + + +/* Parse STMT looking for operands. When finished, the various + build_* operand vectors will have potential operands in them. */ + +static void +parse_ssa_operands (gimple stmt) +{ + enum gimple_code code = gimple_code (stmt); + + if (code == GIMPLE_ASM) + get_asm_expr_operands (stmt); + else if (is_gimple_debug (stmt)) + { + if (gimple_debug_bind_p (stmt) + && gimple_debug_bind_has_value_p (stmt)) + get_expr_operands (stmt, gimple_debug_bind_get_value_ptr (stmt), + opf_use | opf_no_vops); + } + else + { + size_t i, start = 0; + + if (code == GIMPLE_ASSIGN || code == GIMPLE_CALL) + { + get_expr_operands (stmt, gimple_op_ptr (stmt, 0), opf_def); + start = 1; + } + + for (i = start; i < gimple_num_ops (stmt); i++) + get_expr_operands (stmt, gimple_op_ptr (stmt, i), opf_use); + + /* Add call-clobbered operands, if needed. */ + if (code == GIMPLE_CALL) + maybe_add_call_vops (stmt); + } +} + + +/* Create an operands cache for STMT. */ + +static void +build_ssa_operands (gimple stmt) +{ + /* Initially assume that the statement has no volatile operands. */ + gimple_set_has_volatile_ops (stmt, false); + + start_ssa_stmt_operands (); + parse_ssa_operands (stmt); + finalize_ssa_stmt_operands (stmt); +} + + +/* Releases the operands of STMT back to their freelists, and clears + the stmt operand lists. */ + +void +free_stmt_operands (gimple stmt) +{ + def_optype_p defs = gimple_def_ops (stmt), last_def; + use_optype_p uses = gimple_use_ops (stmt), last_use; + + if (defs) + { + for (last_def = defs; last_def->next; last_def = last_def->next) + continue; + last_def->next = gimple_ssa_operands (cfun)->free_defs; + gimple_ssa_operands (cfun)->free_defs = defs; + gimple_set_def_ops (stmt, NULL); + } + + if (uses) + { + for (last_use = uses; last_use->next; last_use = last_use->next) + delink_imm_use (USE_OP_PTR (last_use)); + delink_imm_use (USE_OP_PTR (last_use)); + last_use->next = gimple_ssa_operands (cfun)->free_uses; + gimple_ssa_operands (cfun)->free_uses = uses; + gimple_set_use_ops (stmt, NULL); + } + + if (gimple_has_mem_ops (stmt)) + { + gimple_set_vuse (stmt, NULL_TREE); + gimple_set_vdef (stmt, NULL_TREE); + } +} + + +/* Get the operands of statement STMT. */ + +void +update_stmt_operands (gimple stmt) +{ + /* If update_stmt_operands is called before SSA is initialized, do + nothing. */ + if (!ssa_operands_active ()) + return; + + timevar_push (TV_TREE_OPS); + + gcc_assert (gimple_modified_p (stmt)); + build_ssa_operands (stmt); + gimple_set_modified (stmt, false); + + timevar_pop (TV_TREE_OPS); +} + + +/* Swap operands EXP0 and EXP1 in statement STMT. No attempt is done + to test the validity of the swap operation. */ + +void +swap_tree_operands (gimple stmt, tree *exp0, tree *exp1) +{ + tree op0, op1; + op0 = *exp0; + op1 = *exp1; + + /* If the operand cache is active, attempt to preserve the relative + positions of these two operands in their respective immediate use + lists. */ + if (ssa_operands_active () && op0 != op1) + { + use_optype_p use0, use1, ptr; + use0 = use1 = NULL; + + /* Find the 2 operands in the cache, if they are there. */ + for (ptr = gimple_use_ops (stmt); ptr; ptr = ptr->next) + if (USE_OP_PTR (ptr)->use == exp0) + { + use0 = ptr; + break; + } + + for (ptr = gimple_use_ops (stmt); ptr; ptr = ptr->next) + if (USE_OP_PTR (ptr)->use == exp1) + { + use1 = ptr; + break; + } + + /* If both uses don't have operand entries, there isn't much we can do + at this point. Presumably we don't need to worry about it. */ + if (use0 && use1) + { + tree *tmp = USE_OP_PTR (use1)->use; + USE_OP_PTR (use1)->use = USE_OP_PTR (use0)->use; + USE_OP_PTR (use0)->use = tmp; + } + } + + /* Now swap the data. */ + *exp0 = op1; + *exp1 = op0; +} + + +/* Scan the immediate_use list for VAR making sure its linked properly. + Return TRUE if there is a problem and emit an error message to F. */ + +DEBUG_FUNCTION bool +verify_imm_links (FILE *f, tree var) +{ + use_operand_p ptr, prev, list; + int count; + + gcc_assert (TREE_CODE (var) == SSA_NAME); + + list = &(SSA_NAME_IMM_USE_NODE (var)); + gcc_assert (list->use == NULL); + + if (list->prev == NULL) + { + gcc_assert (list->next == NULL); + return false; + } + + prev = list; + count = 0; + for (ptr = list->next; ptr != list; ) + { + if (prev != ptr->prev) + goto error; + + if (ptr->use == NULL) + goto error; /* 2 roots, or SAFE guard node. */ + else if (*(ptr->use) != var) + goto error; + + prev = ptr; + ptr = ptr->next; + + /* Avoid infinite loops. 50,000,000 uses probably indicates a + problem. */ + if (count++ > 50000000) + goto error; + } + + /* Verify list in the other direction. */ + prev = list; + for (ptr = list->prev; ptr != list; ) + { + if (prev != ptr->next) + goto error; + prev = ptr; + ptr = ptr->prev; + if (count-- < 0) + goto error; + } + + if (count != 0) + goto error; + + return false; + + error: + if (ptr->loc.stmt && gimple_modified_p (ptr->loc.stmt)) + { + fprintf (f, " STMT MODIFIED. - <%p> ", (void *)ptr->loc.stmt); + print_gimple_stmt (f, ptr->loc.stmt, 0, TDF_SLIM); + } + fprintf (f, " IMM ERROR : (use_p : tree - %p:%p)", (void *)ptr, + (void *)ptr->use); + print_generic_expr (f, USE_FROM_PTR (ptr), TDF_SLIM); + fprintf(f, "\n"); + return true; +} + + +/* Dump all the immediate uses to FILE. */ + +void +dump_immediate_uses_for (FILE *file, tree var) +{ + imm_use_iterator iter; + use_operand_p use_p; + + gcc_assert (var && TREE_CODE (var) == SSA_NAME); + + print_generic_expr (file, var, TDF_SLIM); + fprintf (file, " : -->"); + if (has_zero_uses (var)) + fprintf (file, " no uses.\n"); + else + if (has_single_use (var)) + fprintf (file, " single use.\n"); + else + fprintf (file, "%d uses.\n", num_imm_uses (var)); + + FOR_EACH_IMM_USE_FAST (use_p, iter, var) + { + if (use_p->loc.stmt == NULL && use_p->use == NULL) + fprintf (file, "***end of stmt iterator marker***\n"); + else + if (!is_gimple_reg (USE_FROM_PTR (use_p))) + print_gimple_stmt (file, USE_STMT (use_p), 0, TDF_VOPS|TDF_MEMSYMS); + else + print_gimple_stmt (file, USE_STMT (use_p), 0, TDF_SLIM); + } + fprintf(file, "\n"); +} + + +/* Dump all the immediate uses to FILE. */ + +void +dump_immediate_uses (FILE *file) +{ + tree var; + unsigned int x; + + fprintf (file, "Immediate_uses: \n\n"); + for (x = 1; x < num_ssa_names; x++) + { + var = ssa_name(x); + if (!var) + continue; + dump_immediate_uses_for (file, var); + } +} + + +/* Dump def-use edges on stderr. */ + +DEBUG_FUNCTION void +debug_immediate_uses (void) +{ + dump_immediate_uses (stderr); +} + + +/* Dump def-use edges on stderr. */ + +DEBUG_FUNCTION void +debug_immediate_uses_for (tree var) +{ + dump_immediate_uses_for (stderr, var); +} + + +/* Unlink STMTs virtual definition from the IL by propagating its use. */ + +void +unlink_stmt_vdef (gimple stmt) +{ + use_operand_p use_p; + imm_use_iterator iter; + gimple use_stmt; + tree vdef = gimple_vdef (stmt); + + if (!vdef + || TREE_CODE (vdef) != SSA_NAME) + return; + + FOR_EACH_IMM_USE_STMT (use_stmt, iter, gimple_vdef (stmt)) + { + FOR_EACH_IMM_USE_ON_STMT (use_p, iter) + SET_USE (use_p, gimple_vuse (stmt)); + } + + if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_vdef (stmt))) + SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_vuse (stmt)) = 1; +} + -- cgit v1.2.3