| ------------------------------------------------------------------------------ |
| -- -- |
| -- 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; |