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Diffstat (limited to 'gcc/ada/exp_ch7.ads')
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diff --git a/gcc/ada/exp_ch7.ads b/gcc/ada/exp_ch7.ads new file mode 100644 index 000000000..669f998c4 --- /dev/null +++ b/gcc/ada/exp_ch7.ads @@ -0,0 +1,248 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- E X P _ C H 7 -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 1992-2009, Free Software Foundation, Inc. -- +-- -- +-- GNAT is free software; you can redistribute it and/or modify it under -- +-- terms of the GNU General Public License as published by the Free Soft- -- +-- ware Foundation; either version 3, or (at your option) any later ver- -- +-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- +-- OUT 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 distributed with GNAT; see file COPYING3. If not, go to -- +-- http://www.gnu.org/licenses for a complete copy of the license. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +with Namet; use Namet; +with Types; use Types; + +package Exp_Ch7 is + + procedure Expand_N_Package_Body (N : Node_Id); + procedure Expand_N_Package_Declaration (N : Node_Id); + + ----------------------------- + -- Finalization Management -- + ----------------------------- + + function In_Finalization_Root (E : Entity_Id) return Boolean; + -- True if current scope is in package System.Finalization_Root. Used + -- to avoid certain expansions that would involve circularity in the + -- Rtsfind mechanism. + + procedure Build_Final_List (N : Node_Id; Typ : Entity_Id); + -- Build finalization list for anonymous access types, and for access + -- types that are frozen before their designated types are known to + -- be controlled. + + procedure Build_Controlling_Procs (Typ : Entity_Id); + -- Typ is a record, and array type having controlled components. + -- Create the procedures Deep_Initialize, Deep_Adjust and Deep_Finalize + -- that take care of finalization management at run-time. + + procedure Build_Late_Proc (Typ : Entity_Id; Nam : Name_Id); + -- Build one controlling procedure when a late body overrides one of + -- the controlling operations. + + function Controller_Component (Typ : Entity_Id) return Entity_Id; + -- Returns the entity of the component whose name is 'Name_uController' + + function CW_Or_Has_Controlled_Part (T : Entity_Id) return Boolean; + -- True if T is a class-wide type, or if it has controlled parts ("part" + -- means T or any of its subcomponents). This is the same as + -- Needs_Finalization, except when pragma Restrictions (No_Finalization) + -- applies, in which case we know that class-wide objects do not contain + -- controlled parts. + + procedure Expand_Ctrl_Function_Call (N : Node_Id); + -- Expand a call to a function returning a controlled value. That is to + -- say attach the result of the call to the current finalization list, + -- which is the one of the transient scope created for such constructs. + + function Find_Final_List + (E : Entity_Id; + Ref : Node_Id := Empty) return Node_Id; + -- E is an entity representing a controlled object, a controlled type or a + -- scope. If Ref is not empty, it is a reference to a controlled record, + -- the closest Final list is in the controller component of the record + -- containing Ref, otherwise this function returns a reference to the final + -- list attached to the closest dynamic scope (which can be E itself), + -- creating this final list if necessary. + + function Has_New_Controlled_Component (E : Entity_Id) return Boolean; + -- E is a type entity. Give the same result as Has_Controlled_Component + -- except for tagged extensions where the result is True only if the + -- latest extension contains a controlled component. + + function Make_Attach_Call + (Obj_Ref : Node_Id; + Flist_Ref : Node_Id; + With_Attach : Node_Id) return Node_Id; + -- Attach the referenced object to the referenced Final Chain 'Flist_Ref' + -- With_Attach is an expression of type Short_Short_Integer which can be + -- either '0' to signify no attachment, '1' for attachment to a simply + -- linked list or '2' for attachment to a doubly linked list. + + function Make_Init_Call + (Ref : Node_Id; + Typ : Entity_Id; + Flist_Ref : Node_Id; + With_Attach : Node_Id) return List_Id; + -- Ref is an expression (with no-side effect and is not required to have + -- been previously analyzed) that references the object to be initialized. + -- Typ is the expected type of Ref, which is either a controlled type + -- (Is_Controlled) or a type with controlled components (Has_Controlled). + -- With_Attach is an integer expression which is the attachment level, + -- see System.Finalization_Implementation.Attach_To_Final_List for the + -- documentation of Nb_Link. + -- + -- This function will generate the appropriate calls to make sure that the + -- objects referenced by Ref are initialized. The generated code is quite + -- different for an IS_Controlled type or a HAS_Controlled type, but this + -- is not the problem for the caller, the details are in the body. + + function Make_Adjust_Call + (Ref : Node_Id; + Typ : Entity_Id; + Flist_Ref : Node_Id; + With_Attach : Node_Id; + Allocator : Boolean := False) return List_Id; + -- Ref is an expression (with no-side effect and is not required to have + -- been previously analyzed) that references the object to be adjusted. Typ + -- is the expected type of Ref, which is a controlled type (Is_Controlled) + -- or a type with controlled components (Has_Controlled). With_Attach is an + -- integer expression giving the attachment level (see documentation of + -- Attach_To_Final_List.Nb_Link param documentation in s-finimp.ads. + -- Note: if Typ is Finalize_Storage_Only and the object is at library + -- level, then With_Attach will be ignored, and a zero link level will be + -- passed to Attach_To_Final_List. + -- + -- This function will generate the appropriate calls to make sure that the + -- objects referenced by Ref are adjusted. The generated code is quite + -- different depending on the fact the type IS_Controlled or HAS_Controlled + -- but this is not the problem of the caller, the details are in the body. + -- The objects must be attached when the adjust takes place after an + -- initialization expression but not when it takes place after a regular + -- assignment. + -- + -- If Allocator is True, we are adjusting a newly-created object. The + -- existing chaining pointers should not be left unchanged, because they + -- may come from a bit-for-bit copy of those from an initializing object. + -- So, when this flag is True, if the chaining pointers should otherwise + -- be left unset, instead they are reset to null. + + function Make_Final_Call + (Ref : Node_Id; + Typ : Entity_Id; + With_Detach : Node_Id) return List_Id; + -- Ref is an expression (with no-side effect and is not required to have + -- been previously analyzed) that references the object to be Finalized. + -- Typ is the expected type of Ref, which is a controlled type + -- (Is_Controlled) or a type with controlled components (Has_Controlled). + -- With_Detach is a boolean expression indicating whether to detach the + -- controlled object from whatever finalization list it is currently + -- attached to. + -- + -- This function will generate the appropriate calls to make sure that the + -- objects referenced by Ref are finalized. The generated code is quite + -- different depending on the fact the type IS_Controlled or HAS_Controlled + -- but this is not the problem of the caller, the details are in the body. + -- The objects must be detached when finalizing an unchecked deallocated + -- object but not when finalizing the target of an assignment, it is not + -- necessary either on scope exit. + + function Make_Handler_For_Ctrl_Operation (Loc : Source_Ptr) return Node_Id; + -- Generate an implicit exception handler with an 'others' choice, + -- converting any occurrence to a raise of Program_Error. + + function Needs_Finalization (T : Entity_Id) return Boolean; + -- True if T potentially needs finalization actions. True if T is + -- controlled, or has subcomponents. Also True if T is a class-wide type, + -- because some type extension might add controlled subcomponents, except + -- that if pragma Restrictions (No_Finalization) applies, this is False for + -- class-wide types. + + -------------------------------------------- + -- Task and Protected Object finalization -- + -------------------------------------------- + + function Cleanup_Array + (N : Node_Id; + Obj : Node_Id; + Typ : Entity_Id) return List_Id; + -- Generate loops to finalize any tasks or simple protected objects that + -- are subcomponents of an array. + + function Cleanup_Protected_Object + (N : Node_Id; + Ref : Node_Id) return Node_Id; + -- Generate code to finalize a protected object without entries + + function Cleanup_Record + (N : Node_Id; + Obj : Node_Id; + Typ : Entity_Id) return List_Id; + -- For each subcomponent of a record that contains tasks or simple + -- protected objects, generate the appropriate finalization call. + + function Cleanup_Task + (N : Node_Id; + Ref : Node_Id) return Node_Id; + -- Generate code to finalize a task + + function Has_Simple_Protected_Object (T : Entity_Id) return Boolean; + -- Check whether composite type contains a simple protected component + + function Is_Simple_Protected_Type (T : Entity_Id) return Boolean; + -- Check whether argument is a protected type without entries. Protected + -- types with entries are controlled, and their cleanup is handled by the + -- standard finalization machinery. For simple protected types we generate + -- inline code to release their locks. + + -------------------------------- + -- Transient Scope Management -- + -------------------------------- + + procedure Expand_Cleanup_Actions (N : Node_Id); + -- Expand the necessary stuff into a scope to enable finalization of local + -- objects and deallocation of transient data when exiting the scope. N is + -- a "scope node" that is to say one of the following: N_Block_Statement, + -- N_Subprogram_Body, N_Task_Body, N_Entry_Body. + + procedure Establish_Transient_Scope (N : Node_Id; Sec_Stack : Boolean); + -- Push a new transient scope on the scope stack. N is the node responsible + -- for the need of a transient scope. If Sec_Stack is True then the + -- secondary stack is brought in, otherwise it isn't. + + function Node_To_Be_Wrapped return Node_Id; + -- return the node to be wrapped if the current scope is transient + + procedure Store_Before_Actions_In_Scope (L : List_Id); + -- Append the list L of actions to the end of the before-actions store in + -- the top of the scope stack. + + procedure Store_After_Actions_In_Scope (L : List_Id); + -- Append the list L of actions to the beginning of the after-actions store + -- in the top of the scope stack. + + procedure Wrap_Transient_Declaration (N : Node_Id); + -- N is an object declaration. Expand the finalization calls after the + -- declaration and make the outer scope being the transient one. + + procedure Wrap_Transient_Expression (N : Node_Id); + -- N is a sub-expression. Expand a transient block around an expression + + procedure Wrap_Transient_Statement (N : Node_Id); + -- N is a statement. Expand a transient block around an instruction + +end Exp_Ch7; |