195 lines
9.6 KiB
Ada
195 lines
9.6 KiB
Ada
------------------------------------------------------------------------------
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-- --
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-- GNAT COMPILER COMPONENTS --
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-- --
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-- E X P _ C H 7 --
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-- --
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-- S p e c --
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-- --
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-- $Revision: 1.42 $
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-- --
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-- Copyright (C) 1992-2000 Free Software Foundation, Inc. --
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-- --
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-- GNAT is free software; you can redistribute it and/or modify it under --
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-- terms of the GNU General Public License as published by the Free Soft- --
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-- ware Foundation; either version 2, or (at your option) any later ver- --
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-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
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-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
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-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
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-- for more details. You should have received a copy of the GNU General --
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-- Public License distributed with GNAT; see file COPYING. If not, write --
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-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
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-- MA 02111-1307, USA. --
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-- --
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-- GNAT was originally developed by the GNAT team at New York University. --
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-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
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-- --
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------------------------------------------------------------------------------
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with Types; use Types;
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package Exp_Ch7 is
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procedure Expand_N_Package_Body (N : Node_Id);
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procedure Expand_N_Package_Declaration (N : Node_Id);
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------------------------------
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-- Finalization Management --
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------------------------------
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function In_Finalization_Root (E : Entity_Id) return Boolean;
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-- True if current scope is in package System.Finalization_Root. Used
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-- to avoid certain expansions that would involve circularity in the
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-- Rtsfind mechanism.
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procedure Build_Final_List (N : Node_Id; Typ : Entity_Id);
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-- Build finalization list for anonymous access types, and for access
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-- types that are frozen before their designated types are known to
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-- be controlled.
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procedure Build_Controlling_Procs (Typ : Entity_Id);
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-- Typ is a record, and array type having controlled components.
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-- Create the procedures Deep_Initialize, Deep_Adjust and Deep_Finalize
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-- that take care of finalization management at run-time.
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function Controller_Component (Typ : Entity_Id) return Entity_Id;
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-- Returns the entity of the component whose name is 'Name_uController'
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function Controlled_Type (T : Entity_Id) return Boolean;
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-- True if T potentially needs finalization actions
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function Find_Final_List
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(E : Entity_Id;
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Ref : Node_Id := Empty)
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return Node_Id;
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-- E is an entity representing a controlled object, a controlled type
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-- or a scope. If Ref is not empty, it is a reference to a controlled
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-- record, the closest Final list is in the controller component of
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-- the record containing Ref otherwise this function returns a
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-- reference to the final list attached to the closest dynamic scope
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-- (that can be E itself) creating this final list if necessary.
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function Has_New_Controlled_Component (E : Entity_Id) return Boolean;
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-- E is a type entity. Give the same resul as Has_Controlled_Component
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-- except for tagged extensions where the result is True only if the
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-- latest extension contains a controlled component.
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function Make_Attach_Call
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(Obj_Ref : Node_Id;
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Flist_Ref : Node_Id;
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With_Attach : Node_Id)
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return Node_Id;
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-- Attach the referenced object to the referenced Final Chain
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-- 'Flist_Ref' With_Attach is an expression of type Short_Short_Integer
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-- which can be either '0' to signify no attachment, '1' for
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-- attachement to a simply linked list or '2' for attachement to a
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-- doubly linked list.
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function Make_Init_Call
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(Ref : Node_Id;
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Typ : Entity_Id;
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Flist_Ref : Node_Id;
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With_Attach : Node_Id)
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return List_Id;
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-- Ref is an expression (with no-side effect and is not required to
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-- have been previously analyzed) that references the object to be
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-- initialized. Typ is the expected type of Ref, which is a controlled
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-- type (Is_Controlled) or a type with controlled components
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-- (Has_Controlled). 'Dynamic_Case' controls the way the object is
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-- attached which is different whether the object is dynamically
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-- allocated or not.
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--
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-- This function will generate the appropriate calls to make
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-- sure that the objects referenced by Ref are initialized. The
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-- generate code is quite different depending on the fact the type
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-- IS_Controlled or HAS_Controlled but this is not the problem of the
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-- caller, the details are in the body.
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function Make_Adjust_Call
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(Ref : Node_Id;
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Typ : Entity_Id;
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Flist_Ref : Node_Id;
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With_Attach : Node_Id)
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return List_Id;
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-- Ref is an expression (with no-side effect and is not required to
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-- have been previously analyzed) that references the object to be
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-- adjusted. Typ is the expected type of Ref, which is a controlled
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-- type (Is_Controlled) or a type with controlled components
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-- (Has_Controlled).
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--
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-- This function will generate the appropriate calls to make
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-- sure that the objects referenced by Ref are adjusted. The generated
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-- code is quite different depending on the fact the type IS_Controlled
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-- or HAS_Controlled but this is not the problem of the caller, the
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-- details are in the body. If the parameter With_Attach is set to
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-- True, the finalizable objects involved are attached to the proper
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-- finalization chain. The objects must be attached when the adjust
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-- takes place after an initialization expression but not when it takes
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-- place after a regular assignment.
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--
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-- The description of With_Attach is completely obsolete ???
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function Make_Final_Call
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(Ref : Node_Id;
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Typ : Entity_Id;
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With_Detach : Node_Id)
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return List_Id;
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-- Ref is an expression (with no-side effect and is not required to
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-- have been previously analyzed) that references the object
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-- to be Finalized. Typ is the expected type of Ref, which is a
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-- controlled type (Is_Controlled) or a type with controlled
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-- components (Has_Controlled).
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--
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-- This function will generate the appropriate calls to make
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-- sure that the objects referenced by Ref are finalized. The generated
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-- code is quite different depending on the fact the type IS_Controlled
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-- or HAS_Controlled but this is not the problem of the caller, the
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-- details are in the body. If the parameter With_Detach is set to
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-- True, the finalizable objects involved are detached from the proper
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-- finalization chain. The objects must be detached when finalizing an
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-- unchecked deallocated object but not when finalizing the target of
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-- an assignment, it is not necessary either on scope exit.
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procedure Expand_Ctrl_Function_Call (N : Node_Id);
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-- Expand a call to a function returning a controlled value. That is to
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-- say attach the result of the call to the current finalization list,
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-- which is the one of the transient scope created for such constructs.
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--------------------------------
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-- Transient Scope Management --
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--------------------------------
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procedure Expand_Cleanup_Actions (N : Node_Id);
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-- Expand the necessary stuff into a scope to enable finalization of local
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-- objects and deallocation of transient data when exiting the scope. N is
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-- a "scope node" that is to say one of the following: N_Block_Statement,
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-- N_Subprogram_Body, N_Task_Body, N_Entry_Body.
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procedure Establish_Transient_Scope (N : Node_Id; Sec_Stack : Boolean);
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-- Push a new transient scope on the scope stack. N is the node responsible
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-- for the need of a transient scope. If Sec_Stack is True then the
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-- secondary stack is brought in, otherwise it isn't.
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function Node_To_Be_Wrapped return Node_Id;
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-- return the node to be wrapped if the current scope is transient.
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procedure Store_Before_Actions_In_Scope (L : List_Id);
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-- Append the list L of actions to the end of the before-actions store
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-- in the top of the scope stack
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procedure Store_After_Actions_In_Scope (L : List_Id);
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-- Append the list L of actions to the beginning of the after-actions
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-- store in the top of the scope stack
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procedure Wrap_Transient_Declaration (N : Node_Id);
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-- N is an object declaration. Expand the finalization calls after the
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-- declaration and make the outer scope beeing the transient one.
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procedure Wrap_Transient_Expression (N : Node_Id);
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-- N is a sub-expression. Expand a transient block around an expression
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procedure Wrap_Transient_Statement (N : Node_Id);
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-- N is a statement. Expand a transient block around an instruction
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end Exp_Ch7;
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