------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- E X P _ C H 7 -- -- -- -- S p e c -- -- -- -- Copyright (C) 1992-2005, 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, 51 Franklin Street, Fifth Floor, -- -- Boston, MA 02110-1301, USA. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ 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 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). With_Attach is an integer expression representing -- the level of attachment, see Attach_To_Final_List's Nb_Link param -- documentation in s-finimp.ads. -- -- 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; 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 representing -- the level of attachment, see Attach_To_Final_List's 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. 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. -------------------------------------------- -- 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 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;