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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- E X P _ C H 7 --
-- --
-- S p e c --
-- --
-- $Revision: 1.42 $
-- --
-- Copyright (C) 1992-2000 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 2, 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 COPYING. If not, write --
-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
-- MA 02111-1307, USA. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
-- --
------------------------------------------------------------------------------
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.
function Controller_Component (Typ : Entity_Id) return Entity_Id;
-- Returns the entity of the component whose name is 'Name_uController'
function Controlled_Type (T : Entity_Id) return Boolean;
-- True if T potentially needs finalization actions
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
-- (that 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 resul 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
-- attachement to a simply linked list or '2' for attachement 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 a controlled
-- type (Is_Controlled) or a type with controlled components
-- (Has_Controlled). 'Dynamic_Case' controls the way the object is
-- attached which is different whether the object is dynamically
-- allocated or not.
--
-- This function will generate the appropriate calls to make
-- sure that the objects referenced by Ref are initialized. The
-- generate 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.
function Make_Adjust_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
-- adjusted. Typ is the expected type of Ref, which is a controlled
-- type (Is_Controlled) or a type with controlled components
-- (Has_Controlled).
--
-- 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. If the parameter With_Attach is set to
-- True, the finalizable objects involved are attached to the proper
-- finalization chain. The objects must be attached when the adjust
-- takes place after an initialization expression but not when it takes
-- place after a regular assignment.
--
-- The description of With_Attach is completely obsolete ???
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).
--
-- 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. If the parameter With_Detach is set to
-- True, the finalizable objects involved are detached from the proper
-- finalization chain. 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.
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.
--------------------------------
-- 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 beeing 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;
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