1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 -- This package contains virtually all expansion mechanisms related to
30 with Atree; use Atree;
31 with Debug; use Debug;
32 with Einfo; use Einfo;
33 with Errout; use Errout;
34 with Exp_Ch9; use Exp_Ch9;
35 with Exp_Ch11; use Exp_Ch11;
36 with Exp_Dbug; use Exp_Dbug;
37 with Exp_Dist; use Exp_Dist;
38 with Exp_Disp; use Exp_Disp;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Freeze; use Freeze;
43 with Nlists; use Nlists;
44 with Nmake; use Nmake;
46 with Output; use Output;
47 with Restrict; use Restrict;
48 with Rident; use Rident;
49 with Rtsfind; use Rtsfind;
50 with Sinfo; use Sinfo;
52 with Sem_Aux; use Sem_Aux;
53 with Sem_Ch3; use Sem_Ch3;
54 with Sem_Ch7; use Sem_Ch7;
55 with Sem_Ch8; use Sem_Ch8;
56 with Sem_Res; use Sem_Res;
57 with Sem_Type; use Sem_Type;
58 with Sem_Util; use Sem_Util;
59 with Snames; use Snames;
60 with Stand; use Stand;
61 with Targparm; use Targparm;
62 with Tbuild; use Tbuild;
63 with Uintp; use Uintp;
65 package body Exp_Ch7 is
67 --------------------------------
68 -- Transient Scope Management --
69 --------------------------------
71 -- A transient scope is created when temporary objects are created by the
72 -- compiler. These temporary objects are allocated on the secondary stack
73 -- and the transient scope is responsible for finalizing the object when
74 -- appropriate and reclaiming the memory at the right time. The temporary
75 -- objects are generally the objects allocated to store the result of a
76 -- function returning an unconstrained or a tagged value. Expressions
77 -- needing to be wrapped in a transient scope (functions calls returning
78 -- unconstrained or tagged values) may appear in 3 different contexts which
79 -- lead to 3 different kinds of transient scope expansion:
81 -- 1. In a simple statement (procedure call, assignment, ...). In
82 -- this case the instruction is wrapped into a transient block.
83 -- (See Wrap_Transient_Statement for details)
85 -- 2. In an expression of a control structure (test in a IF statement,
86 -- expression in a CASE statement, ...).
87 -- (See Wrap_Transient_Expression for details)
89 -- 3. In a expression of an object_declaration. No wrapping is possible
90 -- here, so the finalization actions, if any, are done right after the
91 -- declaration and the secondary stack deallocation is done in the
92 -- proper enclosing scope (see Wrap_Transient_Declaration for details)
94 -- Note about functions returning tagged types: it has been decided to
95 -- always allocate their result in the secondary stack, even though is not
96 -- absolutely mandatory when the tagged type is constrained because the
97 -- caller knows the size of the returned object and thus could allocate the
98 -- result in the primary stack. An exception to this is when the function
99 -- builds its result in place, as is done for functions with inherently
100 -- limited result types for Ada 2005. In that case, certain callers may
101 -- pass the address of a constrained object as the target object for the
104 -- By allocating tagged results in the secondary stack a number of
105 -- implementation difficulties are avoided:
107 -- - If it is a dispatching function call, the computation of the size of
108 -- the result is possible but complex from the outside.
110 -- - If the returned type is controlled, the assignment of the returned
111 -- value to the anonymous object involves an Adjust, and we have no
112 -- easy way to access the anonymous object created by the back end.
114 -- - If the returned type is class-wide, this is an unconstrained type
117 -- Furthermore, the small loss in efficiency which is the result of this
118 -- decision is not such a big deal because functions returning tagged types
119 -- are not as common in practice compared to functions returning access to
122 --------------------------------------------------
123 -- Transient Blocks and Finalization Management --
124 --------------------------------------------------
126 function Find_Node_To_Be_Wrapped (N : Node_Id) return Node_Id;
127 -- N is a node which may generate a transient scope. Loop over the parent
128 -- pointers of N until it find the appropriate node to wrap. If it returns
129 -- Empty, it means that no transient scope is needed in this context.
138 Is_Protected_Subprogram : Boolean;
139 Is_Task_Allocation_Block : Boolean;
140 Is_Asynchronous_Call_Block : Boolean;
141 Chained_Cleanup_Action : Node_Id) return Node_Id;
142 -- Expand the clean-up procedure for a controlled and/or transient block,
143 -- and/or task master or task body, or a block used to implement task
144 -- allocation or asynchronous entry calls, or a procedure used to implement
145 -- protected procedures. Clean is the entity for such a procedure. Mark
146 -- is the entity for the secondary stack mark, if empty only controlled
147 -- block clean-up will be performed. Flist is the entity for the local
148 -- final list, if empty only transient scope clean-up will be performed.
149 -- The flags Is_Task and Is_Master control the calls to the corresponding
150 -- finalization actions for a task body or for an entity that is a task
151 -- master. Finally if Chained_Cleanup_Action is present, it is a reference
152 -- to a previous cleanup procedure, a call to which is appended at the
153 -- end of the generated one.
155 procedure Set_Node_To_Be_Wrapped (N : Node_Id);
156 -- Set the field Node_To_Be_Wrapped of the current scope
158 procedure Insert_Actions_In_Scope_Around (N : Node_Id);
159 -- Insert the before-actions kept in the scope stack before N, and the
160 -- after-actions after N, which must be a member of a list.
162 function Make_Transient_Block
164 Action : Node_Id) return Node_Id;
165 -- Create a transient block whose name is Scope, which is also a controlled
166 -- block if Flist is not empty and whose only code is Action (either a
167 -- single statement or single declaration).
169 type Final_Primitives is (Initialize_Case, Adjust_Case, Finalize_Case);
170 -- This enumeration type is defined in order to ease sharing code for
171 -- building finalization procedures for composite types.
173 Name_Of : constant array (Final_Primitives) of Name_Id :=
174 (Initialize_Case => Name_Initialize,
175 Adjust_Case => Name_Adjust,
176 Finalize_Case => Name_Finalize);
178 Deep_Name_Of : constant array (Final_Primitives) of TSS_Name_Type :=
179 (Initialize_Case => TSS_Deep_Initialize,
180 Adjust_Case => TSS_Deep_Adjust,
181 Finalize_Case => TSS_Deep_Finalize);
183 procedure Build_Record_Deep_Procs (Typ : Entity_Id);
184 -- Build the deep Initialize/Adjust/Finalize for a record Typ with
185 -- Has_Component_Component set and store them using the TSS mechanism.
187 procedure Build_Array_Deep_Procs (Typ : Entity_Id);
188 -- Build the deep Initialize/Adjust/Finalize for a record Typ with
189 -- Has_Controlled_Component set and store them using the TSS mechanism.
191 function Make_Deep_Proc
192 (Prim : Final_Primitives;
194 Stmts : List_Id) return Node_Id;
195 -- This function generates the tree for Deep_Initialize, Deep_Adjust or
196 -- Deep_Finalize procedures according to the first parameter, these
197 -- procedures operate on the type Typ. The Stmts parameter gives the body
200 function Make_Deep_Array_Body
201 (Prim : Final_Primitives;
202 Typ : Entity_Id) return List_Id;
203 -- This function generates the list of statements for implementing
204 -- Deep_Initialize, Deep_Adjust or Deep_Finalize procedures according to
205 -- the first parameter, these procedures operate on the array type Typ.
207 function Make_Deep_Record_Body
208 (Prim : Final_Primitives;
209 Typ : Entity_Id) return List_Id;
210 -- This function generates the list of statements for implementing
211 -- Deep_Initialize, Deep_Adjust or Deep_Finalize procedures according to
212 -- the first parameter, these procedures operate on the record type Typ.
214 procedure Check_Visibly_Controlled
215 (Prim : Final_Primitives;
217 E : in out Entity_Id;
218 Cref : in out Node_Id);
219 -- The controlled operation declared for a derived type may not be
220 -- overriding, if the controlled operations of the parent type are
221 -- hidden, for example when the parent is a private type whose full
222 -- view is controlled. For other primitive operations we modify the
223 -- name of the operation to indicate that it is not overriding, but
224 -- this is not possible for Initialize, etc. because they have to be
225 -- retrievable by name. Before generating the proper call to one of
226 -- these operations we check whether Typ is known to be controlled at
227 -- the point of definition. If it is not then we must retrieve the
228 -- hidden operation of the parent and use it instead. This is one
229 -- case that might be solved more cleanly once Overriding pragmas or
230 -- declarations are in place.
232 function Convert_View
235 Ind : Pos := 1) return Node_Id;
236 -- Proc is one of the Initialize/Adjust/Finalize operations, and
237 -- Arg is the argument being passed to it. Ind indicates which
238 -- formal of procedure Proc we are trying to match. This function
239 -- will, if necessary, generate an conversion between the partial
240 -- and full view of Arg to match the type of the formal of Proc,
241 -- or force a conversion to the class-wide type in the case where
242 -- the operation is abstract.
244 -----------------------------
245 -- Finalization Management --
246 -----------------------------
248 -- This part describe how Initialization/Adjustment/Finalization procedures
249 -- are generated and called. Two cases must be considered, types that are
250 -- Controlled (Is_Controlled flag set) and composite types that contain
251 -- controlled components (Has_Controlled_Component flag set). In the first
252 -- case the procedures to call are the user-defined primitive operations
253 -- Initialize/Adjust/Finalize. In the second case, GNAT generates
254 -- Deep_Initialize, Deep_Adjust and Deep_Finalize that are in charge
255 -- of calling the former procedures on the controlled components.
257 -- For records with Has_Controlled_Component set, a hidden "controller"
258 -- component is inserted. This controller component contains its own
259 -- finalization list on which all controlled components are attached
260 -- creating an indirection on the upper-level Finalization list. This
261 -- technique facilitates the management of objects whose number of
262 -- controlled components changes during execution. This controller
263 -- component is itself controlled and is attached to the upper-level
264 -- finalization chain. Its adjust primitive is in charge of calling adjust
265 -- on the components and adjusting the finalization pointer to match their
266 -- new location (see a-finali.adb).
268 -- It is not possible to use a similar technique for arrays that have
269 -- Has_Controlled_Component set. In this case, deep procedures are
270 -- generated that call initialize/adjust/finalize + attachment or
271 -- detachment on the finalization list for all component.
273 -- Initialize calls: they are generated for declarations or dynamic
274 -- allocations of Controlled objects with no initial value. They are always
275 -- followed by an attachment to the current Finalization Chain. For the
276 -- dynamic allocation case this the chain attached to the scope of the
277 -- access type definition otherwise, this is the chain of the current
280 -- Adjust Calls: They are generated on 2 occasions: (1) for
281 -- declarations or dynamic allocations of Controlled objects with an
282 -- initial value. (2) after an assignment. In the first case they are
283 -- followed by an attachment to the final chain, in the second case
286 -- Finalization Calls: They are generated on (1) scope exit, (2)
287 -- assignments, (3) unchecked deallocations. In case (3) they have to
288 -- be detached from the final chain, in case (2) they must not and in
289 -- case (1) this is not important since we are exiting the scope anyway.
293 -- Type extensions will have a new record controller at each derivation
294 -- level containing controlled components. The record controller for
295 -- the parent/ancestor is attached to the finalization list of the
296 -- extension's record controller (i.e. the parent is like a component
297 -- of the extension).
299 -- For types that are both Is_Controlled and Has_Controlled_Components,
300 -- the record controller and the object itself are handled separately.
301 -- It could seem simpler to attach the object at the end of its record
302 -- controller but this would not tackle view conversions properly.
304 -- A classwide type can always potentially have controlled components
305 -- but the record controller of the corresponding actual type may not
306 -- be known at compile time so the dispatch table contains a special
307 -- field that allows to compute the offset of the record controller
308 -- dynamically. See s-finimp.Deep_Tag_Attach and a-tags.RC_Offset.
310 -- Here is a simple example of the expansion of a controlled block :
314 -- Y : Controlled := Init;
320 -- Z : R := (C => X);
329 -- _L : System.FI.Finalizable_Ptr;
331 -- procedure _Clean is
334 -- System.FI.Finalize_List (_L);
342 -- Attach_To_Final_List (_L, Finalizable (X), 1);
343 -- at end: Abort_Undefer;
344 -- Y : Controlled := Init;
346 -- Attach_To_Final_List (_L, Finalizable (Y), 1);
349 -- _C : Record_Controller;
355 -- Deep_Initialize (W, _L, 1);
356 -- at end: Abort_Under;
357 -- Z : R := (C => X);
358 -- Deep_Adjust (Z, _L, 1);
362 -- Deep_Finalize (W, False);
363 -- <save W's final pointers>
365 -- <restore W's final pointers>
366 -- Deep_Adjust (W, _L, 0);
371 function Global_Flist_Ref (Flist_Ref : Node_Id) return Boolean;
372 -- Return True if Flist_Ref refers to a global final list, either the
373 -- object Global_Final_List which is used to attach standalone objects,
374 -- or any of the list controllers associated with library-level access
375 -- to controlled objects.
377 procedure Clean_Simple_Protected_Objects (N : Node_Id);
378 -- Protected objects without entries are not controlled types, and the
379 -- locks have to be released explicitly when such an object goes out
380 -- of scope. Traverse declarations in scope to determine whether such
381 -- objects are present.
383 ----------------------------
384 -- Build_Array_Deep_Procs --
385 ----------------------------
387 procedure Build_Array_Deep_Procs (Typ : Entity_Id) is
391 Prim => Initialize_Case,
393 Stmts => Make_Deep_Array_Body (Initialize_Case, Typ)));
395 if not Is_Immutably_Limited_Type (Typ) then
400 Stmts => Make_Deep_Array_Body (Adjust_Case, Typ)));
405 Prim => Finalize_Case,
407 Stmts => Make_Deep_Array_Body (Finalize_Case, Typ)));
408 end Build_Array_Deep_Procs;
410 -----------------------------
411 -- Build_Controlling_Procs --
412 -----------------------------
414 procedure Build_Controlling_Procs (Typ : Entity_Id) is
416 if Is_Array_Type (Typ) then
417 Build_Array_Deep_Procs (Typ);
419 else pragma Assert (Is_Record_Type (Typ));
420 Build_Record_Deep_Procs (Typ);
422 end Build_Controlling_Procs;
424 ----------------------
425 -- Build_Final_List --
426 ----------------------
428 procedure Build_Final_List (N : Node_Id; Typ : Entity_Id) is
429 Loc : constant Source_Ptr := Sloc (N);
433 Set_Associated_Final_Chain (Typ,
434 Make_Defining_Identifier (Loc,
435 New_External_Name (Chars (Typ), 'L')));
438 Make_Object_Declaration (Loc,
439 Defining_Identifier =>
440 Associated_Final_Chain (Typ),
443 (RTE (RE_List_Controller), Loc));
445 -- If the type is declared in a package declaration and designates a
446 -- Taft amendment type that requires finalization, place declaration
447 -- of finalization list in the body, because no client of the package
448 -- can create objects of the type and thus make use of this list. This
449 -- ensures the tree for the spec is identical whenever it is compiled.
451 if Has_Completion_In_Body (Directly_Designated_Type (Typ))
452 and then In_Package_Body (Current_Scope)
453 and then Nkind (Unit (Cunit (Current_Sem_Unit))) = N_Package_Body
455 Nkind (Parent (Declaration_Node (Typ))) = N_Package_Specification
457 Insert_Action (Parent (Designated_Type (Typ)), Decl);
459 -- The type may have been frozen already, and this is a late freezing
460 -- action, in which case the declaration must be elaborated at once.
461 -- If the call is for an allocator, the chain must also be created now,
462 -- because the freezing of the type does not build one. Otherwise, the
463 -- declaration is one of the freezing actions for a user-defined type.
465 elsif Is_Frozen (Typ)
466 or else (Nkind (N) = N_Allocator
467 and then Ekind (Etype (N)) = E_Anonymous_Access_Type)
469 Insert_Action (N, Decl);
472 Append_Freeze_Action (Typ, Decl);
474 end Build_Final_List;
476 ---------------------
477 -- Build_Late_Proc --
478 ---------------------
480 procedure Build_Late_Proc (Typ : Entity_Id; Nam : Name_Id) is
482 for Final_Prim in Name_Of'Range loop
483 if Name_Of (Final_Prim) = Nam then
488 Stmts => Make_Deep_Record_Body (Final_Prim, Typ)));
493 -----------------------------
494 -- Build_Record_Deep_Procs --
495 -----------------------------
497 procedure Build_Record_Deep_Procs (Typ : Entity_Id) is
501 Prim => Initialize_Case,
503 Stmts => Make_Deep_Record_Body (Initialize_Case, Typ)));
505 if not Is_Immutably_Limited_Type (Typ) then
510 Stmts => Make_Deep_Record_Body (Adjust_Case, Typ)));
515 Prim => Finalize_Case,
517 Stmts => Make_Deep_Record_Body (Finalize_Case, Typ)));
518 end Build_Record_Deep_Procs;
524 function Cleanup_Array
527 Typ : Entity_Id) return List_Id
529 Loc : constant Source_Ptr := Sloc (N);
530 Index_List : constant List_Id := New_List;
532 function Free_Component return List_Id;
533 -- Generate the code to finalize the task or protected subcomponents
534 -- of a single component of the array.
536 function Free_One_Dimension (Dim : Int) return List_Id;
537 -- Generate a loop over one dimension of the array
543 function Free_Component return List_Id is
544 Stmts : List_Id := New_List;
546 C_Typ : constant Entity_Id := Component_Type (Typ);
549 -- Component type is known to contain tasks or protected objects
552 Make_Indexed_Component (Loc,
553 Prefix => Duplicate_Subexpr_No_Checks (Obj),
554 Expressions => Index_List);
556 Set_Etype (Tsk, C_Typ);
558 if Is_Task_Type (C_Typ) then
559 Append_To (Stmts, Cleanup_Task (N, Tsk));
561 elsif Is_Simple_Protected_Type (C_Typ) then
562 Append_To (Stmts, Cleanup_Protected_Object (N, Tsk));
564 elsif Is_Record_Type (C_Typ) then
565 Stmts := Cleanup_Record (N, Tsk, C_Typ);
567 elsif Is_Array_Type (C_Typ) then
568 Stmts := Cleanup_Array (N, Tsk, C_Typ);
574 ------------------------
575 -- Free_One_Dimension --
576 ------------------------
578 function Free_One_Dimension (Dim : Int) return List_Id is
582 if Dim > Number_Dimensions (Typ) then
583 return Free_Component;
585 -- Here we generate the required loop
588 Index := Make_Temporary (Loc, 'J');
589 Append (New_Reference_To (Index, Loc), Index_List);
592 Make_Implicit_Loop_Statement (N,
595 Make_Iteration_Scheme (Loc,
596 Loop_Parameter_Specification =>
597 Make_Loop_Parameter_Specification (Loc,
598 Defining_Identifier => Index,
599 Discrete_Subtype_Definition =>
600 Make_Attribute_Reference (Loc,
601 Prefix => Duplicate_Subexpr (Obj),
602 Attribute_Name => Name_Range,
603 Expressions => New_List (
604 Make_Integer_Literal (Loc, Dim))))),
605 Statements => Free_One_Dimension (Dim + 1)));
607 end Free_One_Dimension;
609 -- Start of processing for Cleanup_Array
612 return Free_One_Dimension (1);
619 function Cleanup_Record
622 Typ : Entity_Id) return List_Id
624 Loc : constant Source_Ptr := Sloc (N);
627 Stmts : constant List_Id := New_List;
628 U_Typ : constant Entity_Id := Underlying_Type (Typ);
631 if Has_Discriminants (U_Typ)
632 and then Nkind (Parent (U_Typ)) = N_Full_Type_Declaration
634 Nkind (Type_Definition (Parent (U_Typ))) = N_Record_Definition
638 (Component_List (Type_Definition (Parent (U_Typ)))))
640 -- For now, do not attempt to free a component that may appear in
641 -- a variant, and instead issue a warning. Doing this "properly"
642 -- would require building a case statement and would be quite a
643 -- mess. Note that the RM only requires that free "work" for the
644 -- case of a task access value, so already we go way beyond this
645 -- in that we deal with the array case and non-discriminated
649 ("task/protected object in variant record will not be freed?", N);
650 return New_List (Make_Null_Statement (Loc));
653 Comp := First_Component (Typ);
655 while Present (Comp) loop
656 if Has_Task (Etype (Comp))
657 or else Has_Simple_Protected_Object (Etype (Comp))
660 Make_Selected_Component (Loc,
661 Prefix => Duplicate_Subexpr_No_Checks (Obj),
662 Selector_Name => New_Occurrence_Of (Comp, Loc));
663 Set_Etype (Tsk, Etype (Comp));
665 if Is_Task_Type (Etype (Comp)) then
666 Append_To (Stmts, Cleanup_Task (N, Tsk));
668 elsif Is_Simple_Protected_Type (Etype (Comp)) then
669 Append_To (Stmts, Cleanup_Protected_Object (N, Tsk));
671 elsif Is_Record_Type (Etype (Comp)) then
673 -- Recurse, by generating the prefix of the argument to
674 -- the eventual cleanup call.
677 (Stmts, Cleanup_Record (N, Tsk, Etype (Comp)));
679 elsif Is_Array_Type (Etype (Comp)) then
681 (Stmts, Cleanup_Array (N, Tsk, Etype (Comp)));
685 Next_Component (Comp);
691 ------------------------------
692 -- Cleanup_Protected_Object --
693 ------------------------------
695 function Cleanup_Protected_Object
697 Ref : Node_Id) return Node_Id
699 Loc : constant Source_Ptr := Sloc (N);
703 Make_Procedure_Call_Statement (Loc,
704 Name => New_Reference_To (RTE (RE_Finalize_Protection), Loc),
705 Parameter_Associations => New_List (
706 Concurrent_Ref (Ref)));
707 end Cleanup_Protected_Object;
709 ------------------------------------
710 -- Clean_Simple_Protected_Objects --
711 ------------------------------------
713 procedure Clean_Simple_Protected_Objects (N : Node_Id) is
714 Stmts : constant List_Id := Statements (Handled_Statement_Sequence (N));
715 Stmt : Node_Id := Last (Stmts);
719 E := First_Entity (Current_Scope);
720 while Present (E) loop
721 if (Ekind (E) = E_Variable
722 or else Ekind (E) = E_Constant)
723 and then Has_Simple_Protected_Object (Etype (E))
724 and then not Has_Task (Etype (E))
725 and then Nkind (Parent (E)) /= N_Object_Renaming_Declaration
728 Typ : constant Entity_Id := Etype (E);
729 Ref : constant Node_Id := New_Occurrence_Of (E, Sloc (Stmt));
732 if Is_Simple_Protected_Type (Typ) then
733 Append_To (Stmts, Cleanup_Protected_Object (N, Ref));
735 elsif Has_Simple_Protected_Object (Typ) then
736 if Is_Record_Type (Typ) then
737 Append_List_To (Stmts, Cleanup_Record (N, Ref, Typ));
739 elsif Is_Array_Type (Typ) then
740 Append_List_To (Stmts, Cleanup_Array (N, Ref, Typ));
749 -- Analyze inserted cleanup statements
751 if Present (Stmt) then
754 while Present (Stmt) loop
759 end Clean_Simple_Protected_Objects;
765 function Cleanup_Task
767 Ref : Node_Id) return Node_Id
769 Loc : constant Source_Ptr := Sloc (N);
772 Make_Procedure_Call_Statement (Loc,
773 Name => New_Reference_To (RTE (RE_Free_Task), Loc),
774 Parameter_Associations =>
775 New_List (Concurrent_Ref (Ref)));
778 ---------------------------------
779 -- Has_Simple_Protected_Object --
780 ---------------------------------
782 function Has_Simple_Protected_Object (T : Entity_Id) return Boolean is
786 if Is_Simple_Protected_Type (T) then
789 elsif Is_Array_Type (T) then
790 return Has_Simple_Protected_Object (Component_Type (T));
792 elsif Is_Record_Type (T) then
793 Comp := First_Component (T);
795 while Present (Comp) loop
796 if Has_Simple_Protected_Object (Etype (Comp)) then
800 Next_Component (Comp);
808 end Has_Simple_Protected_Object;
810 ------------------------------
811 -- Is_Simple_Protected_Type --
812 ------------------------------
814 function Is_Simple_Protected_Type (T : Entity_Id) return Boolean is
816 return Is_Protected_Type (T) and then not Has_Entries (T);
817 end Is_Simple_Protected_Type;
819 ------------------------------
820 -- Check_Visibly_Controlled --
821 ------------------------------
823 procedure Check_Visibly_Controlled
824 (Prim : Final_Primitives;
826 E : in out Entity_Id;
827 Cref : in out Node_Id)
829 Parent_Type : Entity_Id;
833 if Is_Derived_Type (Typ)
834 and then Comes_From_Source (E)
835 and then not Is_Overriding_Operation (E)
837 -- We know that the explicit operation on the type does not override
838 -- the inherited operation of the parent, and that the derivation
839 -- is from a private type that is not visibly controlled.
841 Parent_Type := Etype (Typ);
842 Op := Find_Prim_Op (Parent_Type, Name_Of (Prim));
847 -- Wrap the object to be initialized into the proper
848 -- unchecked conversion, to be compatible with the operation
851 if Nkind (Cref) = N_Unchecked_Type_Conversion then
852 Cref := Unchecked_Convert_To (Parent_Type, Expression (Cref));
854 Cref := Unchecked_Convert_To (Parent_Type, Cref);
858 end Check_Visibly_Controlled;
860 -------------------------------
861 -- CW_Or_Has_Controlled_Part --
862 -------------------------------
864 function CW_Or_Has_Controlled_Part (T : Entity_Id) return Boolean is
866 return Is_Class_Wide_Type (T) or else Needs_Finalization (T);
867 end CW_Or_Has_Controlled_Part;
869 --------------------------
870 -- Controller_Component --
871 --------------------------
873 function Controller_Component (Typ : Entity_Id) return Entity_Id is
874 T : Entity_Id := Base_Type (Typ);
876 Comp_Scop : Entity_Id;
877 Res : Entity_Id := Empty;
878 Res_Scop : Entity_Id := Empty;
881 if Is_Class_Wide_Type (T) then
885 if Is_Private_Type (T) then
886 T := Underlying_Type (T);
889 -- Fetch the outermost controller
891 Comp := First_Entity (T);
892 while Present (Comp) loop
893 if Chars (Comp) = Name_uController then
894 Comp_Scop := Scope (Original_Record_Component (Comp));
896 -- If this controller is at the outermost level, no need to
897 -- look for another one
899 if Comp_Scop = T then
902 -- Otherwise record the outermost one and continue looking
904 elsif Res = Empty or else Is_Ancestor (Res_Scop, Comp_Scop) then
906 Res_Scop := Comp_Scop;
913 -- If we fall through the loop, there is no controller component
916 end Controller_Component;
922 function Convert_View
925 Ind : Pos := 1) return Node_Id
927 Fent : Entity_Id := First_Entity (Proc);
932 for J in 2 .. Ind loop
936 Ftyp := Etype (Fent);
938 if Nkind_In (Arg, N_Type_Conversion, N_Unchecked_Type_Conversion) then
939 Atyp := Entity (Subtype_Mark (Arg));
944 if Is_Abstract_Subprogram (Proc) and then Is_Tagged_Type (Ftyp) then
945 return Unchecked_Convert_To (Class_Wide_Type (Ftyp), Arg);
948 and then Present (Atyp)
950 (Is_Private_Type (Ftyp) or else Is_Private_Type (Atyp))
952 Base_Type (Underlying_Type (Atyp)) =
953 Base_Type (Underlying_Type (Ftyp))
955 return Unchecked_Convert_To (Ftyp, Arg);
957 -- If the argument is already a conversion, as generated by
958 -- Make_Init_Call, set the target type to the type of the formal
959 -- directly, to avoid spurious typing problems.
961 elsif Nkind_In (Arg, N_Unchecked_Type_Conversion, N_Type_Conversion)
962 and then not Is_Class_Wide_Type (Atyp)
964 Set_Subtype_Mark (Arg, New_Occurrence_Of (Ftyp, Sloc (Arg)));
965 Set_Etype (Arg, Ftyp);
973 -------------------------------
974 -- Establish_Transient_Scope --
975 -------------------------------
977 -- This procedure is called each time a transient block has to be inserted
978 -- that is to say for each call to a function with unconstrained or tagged
979 -- result. It creates a new scope on the stack scope in order to enclose
980 -- all transient variables generated
982 procedure Establish_Transient_Scope (N : Node_Id; Sec_Stack : Boolean) is
983 Loc : constant Source_Ptr := Sloc (N);
987 -- Nothing to do for virtual machines where memory is GCed
989 if VM_Target /= No_VM then
993 -- Do not create a transient scope if we are already inside one
995 for S in reverse Scope_Stack.First .. Scope_Stack.Last loop
996 if Scope_Stack.Table (S).Is_Transient then
998 Set_Uses_Sec_Stack (Scope_Stack.Table (S).Entity);
1003 -- If we have encountered Standard there are no enclosing
1004 -- transient scopes.
1006 elsif Scope_Stack.Table (S).Entity = Standard_Standard then
1012 Wrap_Node := Find_Node_To_Be_Wrapped (N);
1014 -- Case of no wrap node, false alert, no transient scope needed
1016 if No (Wrap_Node) then
1019 -- If the node to wrap is an iteration_scheme, the expression is
1020 -- one of the bounds, and the expansion will make an explicit
1021 -- declaration for it (see Analyze_Iteration_Scheme, sem_ch5.adb),
1022 -- so do not apply any transformations here.
1024 elsif Nkind (Wrap_Node) = N_Iteration_Scheme then
1028 Push_Scope (New_Internal_Entity (E_Block, Current_Scope, Loc, 'B'));
1029 Set_Scope_Is_Transient;
1032 Set_Uses_Sec_Stack (Current_Scope);
1033 Check_Restriction (No_Secondary_Stack, N);
1036 Set_Etype (Current_Scope, Standard_Void_Type);
1037 Set_Node_To_Be_Wrapped (Wrap_Node);
1039 if Debug_Flag_W then
1040 Write_Str (" <Transient>");
1044 end Establish_Transient_Scope;
1046 ----------------------------
1047 -- Expand_Cleanup_Actions --
1048 ----------------------------
1050 procedure Expand_Cleanup_Actions (N : Node_Id) is
1051 S : constant Entity_Id := Current_Scope;
1052 Flist : constant Entity_Id := Finalization_Chain_Entity (S);
1053 Is_Task : constant Boolean := Nkind (Original_Node (N)) = N_Task_Body;
1055 Is_Master : constant Boolean :=
1056 Nkind (N) /= N_Entry_Body
1057 and then Is_Task_Master (N);
1058 Is_Protected : constant Boolean :=
1059 Nkind (N) = N_Subprogram_Body
1060 and then Is_Protected_Subprogram_Body (N);
1061 Is_Task_Allocation : constant Boolean :=
1062 Nkind (N) = N_Block_Statement
1063 and then Is_Task_Allocation_Block (N);
1064 Is_Asynchronous_Call : constant Boolean :=
1065 Nkind (N) = N_Block_Statement
1066 and then Is_Asynchronous_Call_Block (N);
1068 Previous_At_End_Proc : constant Node_Id :=
1069 At_End_Proc (Handled_Statement_Sequence (N));
1073 Mark : Entity_Id := Empty;
1074 New_Decls : constant List_Id := New_List;
1078 Chain : Entity_Id := Empty;
1083 -- If we are generating expanded code for debugging purposes, use
1084 -- the Sloc of the point of insertion for the cleanup code. The Sloc
1085 -- will be updated subsequently to reference the proper line in the
1086 -- .dg file. If we are not debugging generated code, use instead
1087 -- No_Location, so that no debug information is generated for the
1088 -- cleanup code. This makes the behavior of the NEXT command in GDB
1089 -- monotonic, and makes the placement of breakpoints more accurate.
1091 if Debug_Generated_Code then
1097 -- There are cleanup actions only if the secondary stack needs
1098 -- releasing or some finalizations are needed or in the context
1101 if Uses_Sec_Stack (Current_Scope)
1102 and then not Sec_Stack_Needed_For_Return (Current_Scope)
1106 and then not Is_Master
1107 and then not Is_Task
1108 and then not Is_Protected
1109 and then not Is_Task_Allocation
1110 and then not Is_Asynchronous_Call
1112 Clean_Simple_Protected_Objects (N);
1116 -- If the current scope is the subprogram body that is the rewriting
1117 -- of a task body, and the descriptors have not been delayed (due to
1118 -- some nested instantiations) do not generate redundant cleanup
1119 -- actions: the cleanup procedure already exists for this body.
1121 if Nkind (N) = N_Subprogram_Body
1122 and then Nkind (Original_Node (N)) = N_Task_Body
1123 and then not Delay_Subprogram_Descriptors (Corresponding_Spec (N))
1128 -- Set polling off, since we don't need to poll during cleanup
1129 -- actions, and indeed for the cleanup routine, which is executed
1130 -- with aborts deferred, we don't want polling.
1132 Old_Poll := Polling_Required;
1133 Polling_Required := False;
1135 -- Make sure we have a declaration list, since we will add to it
1137 if No (Declarations (N)) then
1138 Set_Declarations (N, New_List);
1141 -- The task activation call has already been built for task
1142 -- allocation blocks.
1144 if not Is_Task_Allocation then
1145 Build_Task_Activation_Call (N);
1149 Establish_Task_Master (N);
1152 -- If secondary stack is in use, expand:
1153 -- _Mxx : constant Mark_Id := SS_Mark;
1155 -- Suppress calls to SS_Mark and SS_Release if VM_Target,
1156 -- since we never use the secondary stack on the VM.
1158 if Uses_Sec_Stack (Current_Scope)
1159 and then not Sec_Stack_Needed_For_Return (Current_Scope)
1160 and then VM_Target = No_VM
1162 Mark := Make_Temporary (Loc, 'M');
1163 Append_To (New_Decls,
1164 Make_Object_Declaration (Loc,
1165 Defining_Identifier => Mark,
1166 Object_Definition => New_Reference_To (RTE (RE_Mark_Id), Loc),
1168 Make_Function_Call (Loc,
1169 Name => New_Reference_To (RTE (RE_SS_Mark), Loc))));
1171 Set_Uses_Sec_Stack (Current_Scope, False);
1174 -- If finalization list is present then expand:
1175 -- Local_Final_List : System.FI.Finalizable_Ptr;
1177 if Present (Flist) then
1178 Append_To (New_Decls,
1179 Make_Object_Declaration (Loc,
1180 Defining_Identifier => Flist,
1181 Object_Definition =>
1182 New_Reference_To (RTE (RE_Finalizable_Ptr), Loc)));
1185 -- Clean-up procedure definition
1187 Clean := Make_Defining_Identifier (Loc, Name_uClean);
1188 Set_Suppress_Elaboration_Warnings (Clean);
1189 Append_To (New_Decls,
1190 Make_Clean (N, Clean, Mark, Flist,
1195 Is_Asynchronous_Call,
1196 Previous_At_End_Proc));
1198 -- The previous AT END procedure, if any, has been captured in Clean:
1199 -- reset it to Empty now because we check further on that we never
1200 -- overwrite an existing AT END call.
1202 Set_At_End_Proc (Handled_Statement_Sequence (N), Empty);
1204 -- If exception handlers are present, wrap the Sequence of statements in
1205 -- a block because it is not possible to get exception handlers and an
1206 -- AT END call in the same scope.
1208 if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then
1210 -- Preserve end label to provide proper cross-reference information
1212 End_Lab := End_Label (Handled_Statement_Sequence (N));
1214 Make_Block_Statement (Loc,
1215 Handled_Statement_Sequence => Handled_Statement_Sequence (N));
1216 Set_Handled_Statement_Sequence (N,
1217 Make_Handled_Sequence_Of_Statements (Loc, New_List (Blok)));
1218 Set_End_Label (Handled_Statement_Sequence (N), End_Lab);
1221 -- Comment needed here, see RH for 1.306 ???
1223 if Nkind (N) = N_Subprogram_Body then
1224 Set_Has_Nested_Block_With_Handler (Current_Scope);
1227 -- Otherwise we do not wrap
1234 -- Don't move the _chain Activation_Chain declaration in task
1235 -- allocation blocks. Task allocation blocks use this object
1236 -- in their cleanup handlers, and gigi complains if it is declared
1237 -- in the sequence of statements of the scope that declares the
1240 if Is_Task_Allocation then
1241 Chain := Activation_Chain_Entity (N);
1243 Decl := First (Declarations (N));
1244 while Nkind (Decl) /= N_Object_Declaration
1245 or else Defining_Identifier (Decl) /= Chain
1248 pragma Assert (Present (Decl));
1252 Prepend_To (New_Decls, Decl);
1255 -- Now we move the declarations into the Sequence of statements
1256 -- in order to get them protected by the AT END call. It may seem
1257 -- weird to put declarations in the sequence of statement but in
1258 -- fact nothing forbids that at the tree level. We also set the
1259 -- First_Real_Statement field so that we remember where the real
1260 -- statements (i.e. original statements) begin. Note that if we
1261 -- wrapped the statements, the first real statement is inside the
1262 -- inner block. If the First_Real_Statement is already set (as is
1263 -- the case for subprogram bodies that are expansions of task bodies)
1264 -- then do not reset it, because its declarative part would migrate
1265 -- to the statement part.
1268 if No (First_Real_Statement (Handled_Statement_Sequence (N))) then
1269 Set_First_Real_Statement (Handled_Statement_Sequence (N),
1270 First (Statements (Handled_Statement_Sequence (N))));
1274 Set_First_Real_Statement (Handled_Statement_Sequence (N), Blok);
1277 Append_List_To (Declarations (N),
1278 Statements (Handled_Statement_Sequence (N)));
1279 Set_Statements (Handled_Statement_Sequence (N), Declarations (N));
1281 -- We need to reset the Sloc of the handled statement sequence to
1282 -- properly reflect the new initial "statement" in the sequence.
1285 (Handled_Statement_Sequence (N), Sloc (First (Declarations (N))));
1287 -- The declarations of the _Clean procedure and finalization chain
1288 -- replace the old declarations that have been moved inward.
1290 Set_Declarations (N, New_Decls);
1291 Analyze_Declarations (New_Decls);
1293 -- The At_End call is attached to the sequence of statements
1299 -- If the construct is a protected subprogram, then the call to
1300 -- the corresponding unprotected subprogram appears in a block which
1301 -- is the last statement in the body, and it is this block that must
1302 -- be covered by the At_End handler.
1304 if Is_Protected then
1305 HSS := Handled_Statement_Sequence
1306 (Last (Statements (Handled_Statement_Sequence (N))));
1308 HSS := Handled_Statement_Sequence (N);
1311 -- Never overwrite an existing AT END call
1313 pragma Assert (No (At_End_Proc (HSS)));
1315 Set_At_End_Proc (HSS, New_Occurrence_Of (Clean, Loc));
1316 Expand_At_End_Handler (HSS, Empty);
1319 -- Restore saved polling mode
1321 Polling_Required := Old_Poll;
1322 end Expand_Cleanup_Actions;
1324 -------------------------------
1325 -- Expand_Ctrl_Function_Call --
1326 -------------------------------
1328 procedure Expand_Ctrl_Function_Call (N : Node_Id) is
1329 Loc : constant Source_Ptr := Sloc (N);
1330 Rtype : constant Entity_Id := Etype (N);
1331 Utype : constant Entity_Id := Underlying_Type (Rtype);
1334 Action2 : Node_Id := Empty;
1336 Attach_Level : Uint := Uint_1;
1337 Len_Ref : Node_Id := Empty;
1339 function Last_Array_Component
1341 Typ : Entity_Id) return Node_Id;
1342 -- Creates a reference to the last component of the array object
1343 -- designated by Ref whose type is Typ.
1345 --------------------------
1346 -- Last_Array_Component --
1347 --------------------------
1349 function Last_Array_Component
1351 Typ : Entity_Id) return Node_Id
1353 Index_List : constant List_Id := New_List;
1356 for N in 1 .. Number_Dimensions (Typ) loop
1357 Append_To (Index_List,
1358 Make_Attribute_Reference (Loc,
1359 Prefix => Duplicate_Subexpr_No_Checks (Ref),
1360 Attribute_Name => Name_Last,
1361 Expressions => New_List (
1362 Make_Integer_Literal (Loc, N))));
1366 Make_Indexed_Component (Loc,
1367 Prefix => Duplicate_Subexpr (Ref),
1368 Expressions => Index_List);
1369 end Last_Array_Component;
1371 -- Start of processing for Expand_Ctrl_Function_Call
1374 -- Optimization, if the returned value (which is on the sec-stack) is
1375 -- returned again, no need to copy/readjust/finalize, we can just pass
1376 -- the value thru (see Expand_N_Simple_Return_Statement), and thus no
1377 -- attachment is needed
1379 if Nkind (Parent (N)) = N_Simple_Return_Statement then
1383 -- Resolution is now finished, make sure we don't start analysis again
1384 -- because of the duplication.
1387 Ref := Duplicate_Subexpr_No_Checks (N);
1389 -- Now we can generate the Attach Call. Note that this value is always
1390 -- on the (secondary) stack and thus is attached to a singly linked
1393 -- Resx := F (X)'reference;
1394 -- Attach_To_Final_List (_Lx, Resx.all, 1);
1396 -- or when there are controlled components:
1398 -- Attach_To_Final_List (_Lx, Resx._controller, 1);
1400 -- or when it is both Is_Controlled and Has_Controlled_Components:
1402 -- Attach_To_Final_List (_Lx, Resx._controller, 1);
1403 -- Attach_To_Final_List (_Lx, Resx, 1);
1405 -- or if it is an array with Is_Controlled (and Has_Controlled)
1407 -- Attach_To_Final_List (_Lx, Resx (Resx'last), 3);
1409 -- An attach level of 3 means that a whole array is to be attached to
1410 -- the finalization list (including the controlled components).
1412 -- or if it is an array with Has_Controlled_Components but not
1415 -- Attach_To_Final_List (_Lx, Resx (Resx'last)._controller, 3);
1417 -- Case where type has controlled components
1419 if Has_Controlled_Component (Rtype) then
1421 T1 : Entity_Id := Rtype;
1422 T2 : Entity_Id := Utype;
1425 if Is_Array_Type (T2) then
1427 Make_Attribute_Reference (Loc,
1429 Duplicate_Subexpr_Move_Checks
1430 (Unchecked_Convert_To (T2, Ref)),
1431 Attribute_Name => Name_Length);
1434 while Is_Array_Type (T2) loop
1436 Ref := Unchecked_Convert_To (T2, Ref);
1439 Ref := Last_Array_Component (Ref, T2);
1440 Attach_Level := Uint_3;
1441 T1 := Component_Type (T2);
1442 T2 := Underlying_Type (T1);
1445 -- If the type has controlled components, go to the controller
1446 -- except in the case of arrays of controlled objects since in
1447 -- this case objects and their components are already chained
1448 -- and the head of the chain is the last array element.
1450 if Is_Array_Type (Rtype) and then Is_Controlled (T2) then
1453 elsif Has_Controlled_Component (T2) then
1455 Ref := Unchecked_Convert_To (T2, Ref);
1459 Make_Selected_Component (Loc,
1461 Selector_Name => Make_Identifier (Loc, Name_uController));
1465 -- Here we know that 'Ref' has a controller so we may as well attach
1471 Flist_Ref => Find_Final_List (Current_Scope),
1472 With_Attach => Make_Integer_Literal (Loc, Attach_Level));
1474 -- If it is also Is_Controlled we need to attach the global object
1476 if Is_Controlled (Rtype) then
1479 Obj_Ref => Duplicate_Subexpr_No_Checks (N),
1480 Flist_Ref => Find_Final_List (Current_Scope),
1481 With_Attach => Make_Integer_Literal (Loc, Attach_Level));
1484 -- Here, we have a controlled type that does not seem to have controlled
1485 -- components but it could be a class wide type whose further
1486 -- derivations have controlled components. So we don't know if the
1487 -- object itself needs to be attached or if it has a record controller.
1488 -- We need to call a runtime function (Deep_Tag_Attach) which knows what
1489 -- to do thanks to the RC_Offset in the dispatch table.
1493 Make_Procedure_Call_Statement (Loc,
1494 Name => New_Reference_To (RTE (RE_Deep_Tag_Attach), Loc),
1495 Parameter_Associations => New_List (
1496 Find_Final_List (Current_Scope),
1498 Make_Attribute_Reference (Loc,
1500 Attribute_Name => Name_Address),
1502 Make_Integer_Literal (Loc, Attach_Level)));
1505 if Present (Len_Ref) then
1507 Make_Implicit_If_Statement (N,
1508 Condition => Make_Op_Gt (Loc,
1509 Left_Opnd => Len_Ref,
1510 Right_Opnd => Make_Integer_Literal (Loc, 0)),
1511 Then_Statements => New_List (Action));
1514 Insert_Action (N, Action);
1515 if Present (Action2) then
1516 Insert_Action (N, Action2);
1518 end Expand_Ctrl_Function_Call;
1520 ---------------------------
1521 -- Expand_N_Package_Body --
1522 ---------------------------
1524 -- Add call to Activate_Tasks if body is an activator (actual processing
1525 -- is in chapter 9).
1527 -- Generate subprogram descriptor for elaboration routine
1529 -- Encode entity names in package body
1531 procedure Expand_N_Package_Body (N : Node_Id) is
1532 Ent : constant Entity_Id := Corresponding_Spec (N);
1535 -- This is done only for non-generic packages
1537 if Ekind (Ent) = E_Package then
1538 Push_Scope (Corresponding_Spec (N));
1540 -- Build dispatch tables of library level tagged types
1542 if Is_Library_Level_Entity (Ent) then
1543 Build_Static_Dispatch_Tables (N);
1546 Build_Task_Activation_Call (N);
1550 Set_Elaboration_Flag (N, Corresponding_Spec (N));
1551 Set_In_Package_Body (Ent, False);
1553 -- Set to encode entity names in package body before gigi is called
1555 Qualify_Entity_Names (N);
1556 end Expand_N_Package_Body;
1558 ----------------------------------
1559 -- Expand_N_Package_Declaration --
1560 ----------------------------------
1562 -- Add call to Activate_Tasks if there are tasks declared and the package
1563 -- has no body. Note that in Ada83, this may result in premature activation
1564 -- of some tasks, given that we cannot tell whether a body will eventually
1567 procedure Expand_N_Package_Declaration (N : Node_Id) is
1568 Spec : constant Node_Id := Specification (N);
1569 Id : constant Entity_Id := Defining_Entity (N);
1571 No_Body : Boolean := False;
1572 -- True in the case of a package declaration that is a compilation unit
1573 -- and for which no associated body will be compiled in
1574 -- this compilation.
1577 -- Case of a package declaration other than a compilation unit
1579 if Nkind (Parent (N)) /= N_Compilation_Unit then
1582 -- Case of a compilation unit that does not require a body
1584 elsif not Body_Required (Parent (N))
1585 and then not Unit_Requires_Body (Id)
1589 -- Special case of generating calling stubs for a remote call interface
1590 -- package: even though the package declaration requires one, the
1591 -- body won't be processed in this compilation (so any stubs for RACWs
1592 -- declared in the package must be generated here, along with the
1595 elsif Parent (N) = Cunit (Main_Unit)
1596 and then Is_Remote_Call_Interface (Id)
1597 and then Distribution_Stub_Mode = Generate_Caller_Stub_Body
1602 -- For a package declaration that implies no associated body, generate
1603 -- task activation call and RACW supporting bodies now (since we won't
1604 -- have a specific separate compilation unit for that).
1609 if Has_RACW (Id) then
1611 -- Generate RACW subprogram bodies
1613 Decls := Private_Declarations (Spec);
1616 Decls := Visible_Declarations (Spec);
1621 Set_Visible_Declarations (Spec, Decls);
1624 Append_RACW_Bodies (Decls, Id);
1625 Analyze_List (Decls);
1628 if Present (Activation_Chain_Entity (N)) then
1630 -- Generate task activation call as last step of elaboration
1632 Build_Task_Activation_Call (N);
1638 -- Build dispatch tables of library level tagged types
1640 if Is_Compilation_Unit (Id)
1641 or else (Is_Generic_Instance (Id)
1642 and then Is_Library_Level_Entity (Id))
1644 Build_Static_Dispatch_Tables (N);
1647 -- Note: it is not necessary to worry about generating a subprogram
1648 -- descriptor, since the only way to get exception handlers into a
1649 -- package spec is to include instantiations, and that would cause
1650 -- generation of subprogram descriptors to be delayed in any case.
1652 -- Set to encode entity names in package spec before gigi is called
1654 Qualify_Entity_Names (N);
1655 end Expand_N_Package_Declaration;
1657 ---------------------
1658 -- Find_Final_List --
1659 ---------------------
1661 function Find_Final_List
1663 Ref : Node_Id := Empty) return Node_Id
1665 Loc : constant Source_Ptr := Sloc (Ref);
1671 -- If the restriction No_Finalization applies, then there's not any
1672 -- finalization list available to return, so return Empty.
1674 if Restriction_Active (No_Finalization) then
1677 -- Case of an internal component. The Final list is the record
1678 -- controller of the enclosing record.
1680 elsif Present (Ref) then
1684 when N_Unchecked_Type_Conversion | N_Type_Conversion =>
1685 R := Expression (R);
1687 when N_Indexed_Component | N_Explicit_Dereference =>
1690 when N_Selected_Component =>
1694 when N_Identifier =>
1698 raise Program_Error;
1703 Make_Selected_Component (Loc,
1705 Make_Selected_Component (Loc,
1707 Selector_Name => Make_Identifier (Loc, Name_uController)),
1708 Selector_Name => Make_Identifier (Loc, Name_F));
1710 -- Case of a dynamically allocated object whose access type has an
1711 -- Associated_Final_Chain. The final list is the corresponding list
1712 -- controller (the next entity in the scope of the access type with
1713 -- the right type). If the type comes from a With_Type clause, no
1714 -- controller was created, we use the global chain instead. (The code
1715 -- related to with_type clauses should presumably be removed at some
1716 -- point since that feature is obsolete???)
1718 -- An anonymous access type either has a list created for it when the
1719 -- allocator is a for an access parameter or an access discriminant,
1720 -- or else it uses the list of the enclosing dynamic scope, when the
1721 -- context is a declaration or an assignment.
1723 elsif Is_Access_Type (E)
1724 and then (Present (Associated_Final_Chain (E))
1725 or else From_With_Type (E))
1727 if From_With_Type (E) then
1728 return New_Reference_To (RTE (RE_Global_Final_List), Sloc (E));
1730 -- Use the access type's associated finalization chain
1734 Make_Selected_Component (Loc,
1737 (Associated_Final_Chain (Base_Type (E)), Loc),
1738 Selector_Name => Make_Identifier (Loc, Name_F));
1742 S := Nearest_Dynamic_Scope (E);
1744 -- When the finalization chain entity is 'Error', it means that there
1745 -- should not be any chain at that level and that the enclosing one
1748 -- This is a nasty kludge, see ??? note in exp_ch11
1750 while Finalization_Chain_Entity (S) = Error loop
1751 S := Enclosing_Dynamic_Scope (S);
1754 if S = Standard_Standard then
1755 return New_Reference_To (RTE (RE_Global_Final_List), Sloc (E));
1757 if No (Finalization_Chain_Entity (S)) then
1759 -- In the case where the scope is a subprogram, retrieve the
1760 -- Sloc of subprogram's body for association with the chain,
1761 -- since using the Sloc of the spec would be confusing during
1762 -- source-line stepping within the debugger.
1765 Flist_Loc : Source_Ptr := Sloc (S);
1766 Subp_Body : Node_Id;
1769 if Ekind (S) in Subprogram_Kind then
1770 Subp_Body := Unit_Declaration_Node (S);
1772 if Nkind (Subp_Body) /= N_Subprogram_Body then
1773 Subp_Body := Corresponding_Body (Subp_Body);
1776 if Present (Subp_Body) then
1777 Flist_Loc := Sloc (Subp_Body);
1781 Id := Make_Temporary (Flist_Loc, 'F');
1784 Set_Finalization_Chain_Entity (S, Id);
1786 -- Set momentarily some semantics attributes to allow normal
1787 -- analysis of expansions containing references to this chain.
1788 -- Will be fully decorated during the expansion of the scope
1791 Set_Ekind (Id, E_Variable);
1792 Set_Etype (Id, RTE (RE_Finalizable_Ptr));
1795 return New_Reference_To (Finalization_Chain_Entity (S), Sloc (E));
1798 end Find_Final_List;
1800 -----------------------------
1801 -- Find_Node_To_Be_Wrapped --
1802 -----------------------------
1804 function Find_Node_To_Be_Wrapped (N : Node_Id) return Node_Id is
1806 The_Parent : Node_Id;
1812 pragma Assert (P /= Empty);
1813 The_Parent := Parent (P);
1815 case Nkind (The_Parent) is
1817 -- Simple statement can be wrapped
1822 -- Usually assignments are good candidate for wrapping
1823 -- except when they have been generated as part of a
1824 -- controlled aggregate where the wrapping should take
1825 -- place more globally.
1827 when N_Assignment_Statement =>
1828 if No_Ctrl_Actions (The_Parent) then
1834 -- An entry call statement is a special case if it occurs in
1835 -- the context of a Timed_Entry_Call. In this case we wrap
1836 -- the entire timed entry call.
1838 when N_Entry_Call_Statement |
1839 N_Procedure_Call_Statement =>
1840 if Nkind (Parent (The_Parent)) = N_Entry_Call_Alternative
1841 and then Nkind_In (Parent (Parent (The_Parent)),
1843 N_Conditional_Entry_Call)
1845 return Parent (Parent (The_Parent));
1850 -- Object declarations are also a boundary for the transient scope
1851 -- even if they are not really wrapped
1852 -- (see Wrap_Transient_Declaration)
1854 when N_Object_Declaration |
1855 N_Object_Renaming_Declaration |
1856 N_Subtype_Declaration =>
1859 -- The expression itself is to be wrapped if its parent is a
1860 -- compound statement or any other statement where the expression
1861 -- is known to be scalar
1863 when N_Accept_Alternative |
1864 N_Attribute_Definition_Clause |
1867 N_Delay_Alternative |
1868 N_Delay_Until_Statement |
1869 N_Delay_Relative_Statement |
1870 N_Discriminant_Association |
1872 N_Entry_Body_Formal_Part |
1875 N_Iteration_Scheme |
1876 N_Terminate_Alternative =>
1879 when N_Attribute_Reference =>
1881 if Is_Procedure_Attribute_Name
1882 (Attribute_Name (The_Parent))
1887 -- A raise statement can be wrapped. This will arise when the
1888 -- expression in a raise_with_expression uses the secondary
1889 -- stack, for example.
1891 when N_Raise_Statement =>
1894 -- If the expression is within the iteration scheme of a loop,
1895 -- we must create a declaration for it, followed by an assignment
1896 -- in order to have a usable statement to wrap.
1898 when N_Loop_Parameter_Specification =>
1899 return Parent (The_Parent);
1901 -- The following nodes contains "dummy calls" which don't
1902 -- need to be wrapped.
1904 when N_Parameter_Specification |
1905 N_Discriminant_Specification |
1906 N_Component_Declaration =>
1909 -- The return statement is not to be wrapped when the function
1910 -- itself needs wrapping at the outer-level
1912 when N_Simple_Return_Statement =>
1914 Applies_To : constant Entity_Id :=
1916 (Return_Statement_Entity (The_Parent));
1917 Return_Type : constant Entity_Id := Etype (Applies_To);
1919 if Requires_Transient_Scope (Return_Type) then
1926 -- If we leave a scope without having been able to find a node to
1927 -- wrap, something is going wrong but this can happen in error
1928 -- situation that are not detected yet (such as a dynamic string
1929 -- in a pragma export)
1931 when N_Subprogram_Body |
1932 N_Package_Declaration |
1934 N_Block_Statement =>
1937 -- otherwise continue the search
1943 end Find_Node_To_Be_Wrapped;
1945 ----------------------
1946 -- Global_Flist_Ref --
1947 ----------------------
1949 function Global_Flist_Ref (Flist_Ref : Node_Id) return Boolean is
1953 -- Look for the Global_Final_List
1955 if Is_Entity_Name (Flist_Ref) then
1956 Flist := Entity (Flist_Ref);
1958 -- Look for the final list associated with an access to controlled
1960 elsif Nkind (Flist_Ref) = N_Selected_Component
1961 and then Is_Entity_Name (Prefix (Flist_Ref))
1963 Flist := Entity (Prefix (Flist_Ref));
1968 return Present (Flist)
1969 and then Present (Scope (Flist))
1970 and then Enclosing_Dynamic_Scope (Flist) = Standard_Standard;
1971 end Global_Flist_Ref;
1973 ----------------------------------
1974 -- Has_New_Controlled_Component --
1975 ----------------------------------
1977 function Has_New_Controlled_Component (E : Entity_Id) return Boolean is
1981 if not Is_Tagged_Type (E) then
1982 return Has_Controlled_Component (E);
1983 elsif not Is_Derived_Type (E) then
1984 return Has_Controlled_Component (E);
1987 Comp := First_Component (E);
1988 while Present (Comp) loop
1990 if Chars (Comp) = Name_uParent then
1993 elsif Scope (Original_Record_Component (Comp)) = E
1994 and then Needs_Finalization (Etype (Comp))
1999 Next_Component (Comp);
2003 end Has_New_Controlled_Component;
2005 --------------------------
2006 -- In_Finalization_Root --
2007 --------------------------
2009 -- It would seem simpler to test Scope (RTE (RE_Root_Controlled)) but
2010 -- the purpose of this function is to avoid a circular call to Rtsfind
2011 -- which would been caused by such a test.
2013 function In_Finalization_Root (E : Entity_Id) return Boolean is
2014 S : constant Entity_Id := Scope (E);
2017 return Chars (Scope (S)) = Name_System
2018 and then Chars (S) = Name_Finalization_Root
2019 and then Scope (Scope (S)) = Standard_Standard;
2020 end In_Finalization_Root;
2022 ------------------------------------
2023 -- Insert_Actions_In_Scope_Around --
2024 ------------------------------------
2026 procedure Insert_Actions_In_Scope_Around (N : Node_Id) is
2027 SE : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
2031 -- If the node to be wrapped is the triggering statement of an
2032 -- asynchronous select, it is not part of a statement list. The
2033 -- actions must be inserted before the Select itself, which is
2034 -- part of some list of statements. Note that the triggering
2035 -- alternative includes the triggering statement and an optional
2036 -- statement list. If the node to be wrapped is part of that list,
2037 -- the normal insertion applies.
2039 if Nkind (Parent (Node_To_Be_Wrapped)) = N_Triggering_Alternative
2040 and then not Is_List_Member (Node_To_Be_Wrapped)
2042 Target := Parent (Parent (Node_To_Be_Wrapped));
2047 if Present (SE.Actions_To_Be_Wrapped_Before) then
2048 Insert_List_Before (Target, SE.Actions_To_Be_Wrapped_Before);
2049 SE.Actions_To_Be_Wrapped_Before := No_List;
2052 if Present (SE.Actions_To_Be_Wrapped_After) then
2053 Insert_List_After (Target, SE.Actions_To_Be_Wrapped_After);
2054 SE.Actions_To_Be_Wrapped_After := No_List;
2056 end Insert_Actions_In_Scope_Around;
2058 -----------------------
2059 -- Make_Adjust_Call --
2060 -----------------------
2062 function Make_Adjust_Call
2065 Flist_Ref : Node_Id;
2066 With_Attach : Node_Id;
2067 Allocator : Boolean := False) return List_Id
2069 Loc : constant Source_Ptr := Sloc (Ref);
2070 Res : constant List_Id := New_List;
2073 Cref : Node_Id := Ref;
2075 Attach : Node_Id := With_Attach;
2078 if Is_Class_Wide_Type (Typ) then
2079 Utyp := Underlying_Type (Base_Type (Root_Type (Typ)));
2081 Utyp := Underlying_Type (Base_Type (Typ));
2084 Set_Assignment_OK (Cref);
2086 -- Deal with non-tagged derivation of private views
2088 if Is_Untagged_Derivation (Typ) then
2089 Utyp := Underlying_Type (Root_Type (Base_Type (Typ)));
2090 Cref := Unchecked_Convert_To (Utyp, Cref);
2091 Set_Assignment_OK (Cref);
2092 -- To prevent problems with UC see 1.156 RH ???
2095 -- If the underlying_type is a subtype, we are dealing with
2096 -- the completion of a private type. We need to access
2097 -- the base type and generate a conversion to it.
2099 if Utyp /= Base_Type (Utyp) then
2100 pragma Assert (Is_Private_Type (Typ));
2101 Utyp := Base_Type (Utyp);
2102 Cref := Unchecked_Convert_To (Utyp, Cref);
2105 -- If the object is unanalyzed, set its expected type for use
2106 -- in Convert_View in case an additional conversion is needed.
2108 if No (Etype (Cref))
2109 and then Nkind (Cref) /= N_Unchecked_Type_Conversion
2111 Set_Etype (Cref, Typ);
2114 -- We do not need to attach to one of the Global Final Lists
2115 -- the objects whose type is Finalize_Storage_Only
2117 if Finalize_Storage_Only (Typ)
2118 and then (Global_Flist_Ref (Flist_Ref)
2119 or else Entity (Constant_Value (RTE (RE_Garbage_Collected)))
2122 Attach := Make_Integer_Literal (Loc, 0);
2125 -- Special case for allocators: need initialization of the chain
2126 -- pointers. For the 0 case, reset them to null.
2129 pragma Assert (Nkind (Attach) = N_Integer_Literal);
2131 if Intval (Attach) = 0 then
2132 Set_Intval (Attach, Uint_4);
2137 -- Deep_Adjust (Flist_Ref, Ref, Attach);
2139 if Has_Controlled_Component (Utyp)
2140 or else Is_Class_Wide_Type (Typ)
2142 if Is_Tagged_Type (Utyp) then
2143 Proc := Find_Prim_Op (Utyp, TSS_Deep_Adjust);
2146 Proc := TSS (Utyp, TSS_Deep_Adjust);
2149 Cref := Convert_View (Proc, Cref, 2);
2152 Make_Procedure_Call_Statement (Loc,
2153 Name => New_Reference_To (Proc, Loc),
2154 Parameter_Associations =>
2155 New_List (Flist_Ref, Cref, Attach)));
2158 -- if With_Attach then
2159 -- Attach_To_Final_List (Ref, Flist_Ref);
2163 else -- Is_Controlled (Utyp)
2165 Proc := Find_Prim_Op (Utyp, Name_Of (Adjust_Case));
2166 Cref := Convert_View (Proc, Cref);
2167 Cref2 := New_Copy_Tree (Cref);
2170 Make_Procedure_Call_Statement (Loc,
2171 Name => New_Reference_To (Proc, Loc),
2172 Parameter_Associations => New_List (Cref2)));
2174 Append_To (Res, Make_Attach_Call (Cref, Flist_Ref, Attach));
2178 end Make_Adjust_Call;
2180 ----------------------
2181 -- Make_Attach_Call --
2182 ----------------------
2185 -- System.FI.Attach_To_Final_List (Flist, Ref, Nb_Link)
2187 function Make_Attach_Call
2189 Flist_Ref : Node_Id;
2190 With_Attach : Node_Id) return Node_Id
2192 Loc : constant Source_Ptr := Sloc (Obj_Ref);
2195 -- Optimization: If the number of links is statically '0', don't
2196 -- call the attach_proc.
2198 if Nkind (With_Attach) = N_Integer_Literal
2199 and then Intval (With_Attach) = Uint_0
2201 return Make_Null_Statement (Loc);
2205 Make_Procedure_Call_Statement (Loc,
2206 Name => New_Reference_To (RTE (RE_Attach_To_Final_List), Loc),
2207 Parameter_Associations => New_List (
2209 OK_Convert_To (RTE (RE_Finalizable), Obj_Ref),
2211 end Make_Attach_Call;
2223 Is_Master : Boolean;
2224 Is_Protected_Subprogram : Boolean;
2225 Is_Task_Allocation_Block : Boolean;
2226 Is_Asynchronous_Call_Block : Boolean;
2227 Chained_Cleanup_Action : Node_Id) return Node_Id
2229 Loc : constant Source_Ptr := Sloc (Clean);
2230 Stmt : constant List_Id := New_List;
2236 Param_Type : Entity_Id;
2237 Pid : Entity_Id := Empty;
2238 Cancel_Param : Entity_Id;
2242 if Restricted_Profile then
2244 (Stmt, Build_Runtime_Call (Loc, RE_Complete_Restricted_Task));
2246 Append_To (Stmt, Build_Runtime_Call (Loc, RE_Complete_Task));
2249 elsif Is_Master then
2250 if Restriction_Active (No_Task_Hierarchy) = False then
2251 Append_To (Stmt, Build_Runtime_Call (Loc, RE_Complete_Master));
2254 elsif Is_Protected_Subprogram then
2256 -- Add statements to the cleanup handler of the (ordinary)
2257 -- subprogram expanded to implement a protected subprogram,
2258 -- unlocking the protected object parameter and undeferring abort.
2259 -- If this is a protected procedure, and the object contains
2260 -- entries, this also calls the entry service routine.
2262 -- NOTE: This cleanup handler references _object, a parameter
2263 -- to the procedure.
2265 -- Find the _object parameter representing the protected object
2267 Spec := Parent (Corresponding_Spec (N));
2269 Param := First (Parameter_Specifications (Spec));
2271 Param_Type := Etype (Parameter_Type (Param));
2273 if Ekind (Param_Type) = E_Record_Type then
2274 Pid := Corresponding_Concurrent_Type (Param_Type);
2277 exit when No (Param) or else Present (Pid);
2281 pragma Assert (Present (Param));
2283 -- If the associated protected object declares entries,
2284 -- a protected procedure has to service entry queues.
2285 -- In this case, add
2287 -- Service_Entries (_object._object'Access);
2289 -- _object is the record used to implement the protected object.
2290 -- It is a parameter to the protected subprogram.
2292 if Nkind (Specification (N)) = N_Procedure_Specification
2293 and then Has_Entries (Pid)
2295 case Corresponding_Runtime_Package (Pid) is
2296 when System_Tasking_Protected_Objects_Entries =>
2297 Name := New_Reference_To (RTE (RE_Service_Entries), Loc);
2299 when System_Tasking_Protected_Objects_Single_Entry =>
2300 Name := New_Reference_To (RTE (RE_Service_Entry), Loc);
2303 raise Program_Error;
2307 Make_Procedure_Call_Statement (Loc,
2309 Parameter_Associations => New_List (
2310 Make_Attribute_Reference (Loc,
2312 Make_Selected_Component (Loc,
2313 Prefix => New_Reference_To (
2314 Defining_Identifier (Param), Loc),
2316 Make_Identifier (Loc, Name_uObject)),
2317 Attribute_Name => Name_Unchecked_Access))));
2320 -- Unlock (_object._object'Access);
2322 -- object is the record used to implement the protected object.
2323 -- It is a parameter to the protected subprogram.
2325 case Corresponding_Runtime_Package (Pid) is
2326 when System_Tasking_Protected_Objects_Entries =>
2327 Name := New_Reference_To (RTE (RE_Unlock_Entries), Loc);
2329 when System_Tasking_Protected_Objects_Single_Entry =>
2330 Name := New_Reference_To (RTE (RE_Unlock_Entry), Loc);
2332 when System_Tasking_Protected_Objects =>
2333 Name := New_Reference_To (RTE (RE_Unlock), Loc);
2336 raise Program_Error;
2340 Make_Procedure_Call_Statement (Loc,
2342 Parameter_Associations => New_List (
2343 Make_Attribute_Reference (Loc,
2345 Make_Selected_Component (Loc,
2347 New_Reference_To (Defining_Identifier (Param), Loc),
2349 Make_Identifier (Loc, Name_uObject)),
2350 Attribute_Name => Name_Unchecked_Access))));
2353 if Abort_Allowed then
2358 Make_Procedure_Call_Statement (Loc,
2361 RTE (RE_Abort_Undefer), Loc),
2362 Parameter_Associations => Empty_List));
2365 elsif Is_Task_Allocation_Block then
2367 -- Add a call to Expunge_Unactivated_Tasks to the cleanup
2368 -- handler of a block created for the dynamic allocation of
2371 -- Expunge_Unactivated_Tasks (_chain);
2373 -- where _chain is the list of tasks created by the allocator
2374 -- but not yet activated. This list will be empty unless
2375 -- the block completes abnormally.
2377 -- This only applies to dynamically allocated tasks;
2378 -- other unactivated tasks are completed by Complete_Task or
2381 -- NOTE: This cleanup handler references _chain, a local
2385 Make_Procedure_Call_Statement (Loc,
2388 RTE (RE_Expunge_Unactivated_Tasks), Loc),
2389 Parameter_Associations => New_List (
2390 New_Reference_To (Activation_Chain_Entity (N), Loc))));
2392 elsif Is_Asynchronous_Call_Block then
2394 -- Add a call to attempt to cancel the asynchronous entry call
2395 -- whenever the block containing the abortable part is exited.
2397 -- NOTE: This cleanup handler references C, a local object
2399 -- Get the argument to the Cancel procedure
2400 Cancel_Param := Entry_Cancel_Parameter (Entity (Identifier (N)));
2402 -- If it is of type Communication_Block, this must be a
2403 -- protected entry call.
2405 if Is_RTE (Etype (Cancel_Param), RE_Communication_Block) then
2409 -- if Enqueued (Cancel_Parameter) then
2411 Make_Implicit_If_Statement (Clean,
2412 Condition => Make_Function_Call (Loc,
2413 Name => New_Reference_To (
2414 RTE (RE_Enqueued), Loc),
2415 Parameter_Associations => New_List (
2416 New_Reference_To (Cancel_Param, Loc))),
2417 Then_Statements => New_List (
2419 -- Cancel_Protected_Entry_Call (Cancel_Param);
2421 Make_Procedure_Call_Statement (Loc,
2422 Name => New_Reference_To (
2423 RTE (RE_Cancel_Protected_Entry_Call), Loc),
2424 Parameter_Associations => New_List (
2425 New_Reference_To (Cancel_Param, Loc))))));
2427 -- Asynchronous delay
2429 elsif Is_RTE (Etype (Cancel_Param), RE_Delay_Block) then
2431 Make_Procedure_Call_Statement (Loc,
2432 Name => New_Reference_To (RTE (RE_Cancel_Async_Delay), Loc),
2433 Parameter_Associations => New_List (
2434 Make_Attribute_Reference (Loc,
2435 Prefix => New_Reference_To (Cancel_Param, Loc),
2436 Attribute_Name => Name_Unchecked_Access))));
2441 -- Append call to Cancel_Task_Entry_Call (C);
2444 Make_Procedure_Call_Statement (Loc,
2445 Name => New_Reference_To (
2446 RTE (RE_Cancel_Task_Entry_Call),
2448 Parameter_Associations => New_List (
2449 New_Reference_To (Cancel_Param, Loc))));
2454 if Present (Flist) then
2456 Make_Procedure_Call_Statement (Loc,
2457 Name => New_Reference_To (RTE (RE_Finalize_List), Loc),
2458 Parameter_Associations => New_List (
2459 New_Reference_To (Flist, Loc))));
2462 if Present (Mark) then
2464 Make_Procedure_Call_Statement (Loc,
2465 Name => New_Reference_To (RTE (RE_SS_Release), Loc),
2466 Parameter_Associations => New_List (
2467 New_Reference_To (Mark, Loc))));
2470 if Present (Chained_Cleanup_Action) then
2472 Make_Procedure_Call_Statement (Loc,
2473 Name => Chained_Cleanup_Action));
2477 Make_Subprogram_Body (Loc,
2479 Make_Procedure_Specification (Loc,
2480 Defining_Unit_Name => Clean),
2482 Declarations => New_List,
2484 Handled_Statement_Sequence =>
2485 Make_Handled_Sequence_Of_Statements (Loc,
2486 Statements => Stmt));
2488 if Present (Flist) or else Is_Task or else Is_Master then
2489 Wrap_Cleanup_Procedure (Sbody);
2492 -- We do not want debug information for _Clean routines,
2493 -- since it just confuses the debugging operation unless
2494 -- we are debugging generated code.
2496 if not Debug_Generated_Code then
2497 Set_Debug_Info_Off (Clean, True);
2503 --------------------------
2504 -- Make_Deep_Array_Body --
2505 --------------------------
2507 -- Array components are initialized and adjusted in the normal order
2508 -- and finalized in the reverse order. Exceptions are handled and
2509 -- Program_Error is re-raise in the Adjust and Finalize case
2510 -- (RM 7.6.1(12)). Generate the following code :
2512 -- procedure Deep_<P> -- with <P> being Initialize or Adjust or Finalize
2513 -- (L : in out Finalizable_Ptr;
2517 -- for J1 in Typ'First (1) .. Typ'Last (1) loop
2518 -- ^ reverse ^ -- in the finalization case
2520 -- for J2 in Typ'First (n) .. Typ'Last (n) loop
2521 -- Make_<P>_Call (Typ, V (J1, .. , Jn), L, V);
2525 -- exception -- not in the
2526 -- when others => raise Program_Error; -- Initialize case
2529 function Make_Deep_Array_Body
2530 (Prim : Final_Primitives;
2531 Typ : Entity_Id) return List_Id
2533 Loc : constant Source_Ptr := Sloc (Typ);
2535 Index_List : constant List_Id := New_List;
2536 -- Stores the list of references to the indexes (one per dimension)
2538 function One_Component return List_Id;
2539 -- Create one statement to initialize/adjust/finalize one array
2540 -- component, designated by a full set of indexes.
2542 function One_Dimension (N : Int) return List_Id;
2543 -- Create loop to deal with one dimension of the array. The single
2544 -- statement in the body of the loop initializes the inner dimensions if
2545 -- any, or else a single component.
2551 function One_Component return List_Id is
2552 Comp_Typ : constant Entity_Id := Component_Type (Typ);
2553 Comp_Ref : constant Node_Id :=
2554 Make_Indexed_Component (Loc,
2555 Prefix => Make_Identifier (Loc, Name_V),
2556 Expressions => Index_List);
2559 -- Set the etype of the component Reference, which is used to
2560 -- determine whether a conversion to a parent type is needed.
2562 Set_Etype (Comp_Ref, Comp_Typ);
2565 when Initialize_Case =>
2566 return Make_Init_Call (Comp_Ref, Comp_Typ,
2567 Make_Identifier (Loc, Name_L),
2568 Make_Identifier (Loc, Name_B));
2571 return Make_Adjust_Call (Comp_Ref, Comp_Typ,
2572 Make_Identifier (Loc, Name_L),
2573 Make_Identifier (Loc, Name_B));
2575 when Finalize_Case =>
2576 return Make_Final_Call (Comp_Ref, Comp_Typ,
2577 Make_Identifier (Loc, Name_B));
2585 function One_Dimension (N : Int) return List_Id is
2589 if N > Number_Dimensions (Typ) then
2590 return One_Component;
2594 Make_Defining_Identifier (Loc, New_External_Name ('J', N));
2596 Append_To (Index_List, New_Reference_To (Index, Loc));
2599 Make_Implicit_Loop_Statement (Typ,
2600 Identifier => Empty,
2602 Make_Iteration_Scheme (Loc,
2603 Loop_Parameter_Specification =>
2604 Make_Loop_Parameter_Specification (Loc,
2605 Defining_Identifier => Index,
2606 Discrete_Subtype_Definition =>
2607 Make_Attribute_Reference (Loc,
2608 Prefix => Make_Identifier (Loc, Name_V),
2609 Attribute_Name => Name_Range,
2610 Expressions => New_List (
2611 Make_Integer_Literal (Loc, N))),
2612 Reverse_Present => Prim = Finalize_Case)),
2613 Statements => One_Dimension (N + 1)));
2617 -- Start of processing for Make_Deep_Array_Body
2620 return One_Dimension (1);
2621 end Make_Deep_Array_Body;
2623 --------------------
2624 -- Make_Deep_Proc --
2625 --------------------
2628 -- procedure DEEP_<prim>
2629 -- (L : IN OUT Finalizable_Ptr; -- not for Finalize
2630 -- V : IN OUT <typ>;
2631 -- B : IN Short_Short_Integer) is
2634 -- exception -- Finalize and Adjust Cases only
2635 -- raise Program_Error; -- idem
2638 function Make_Deep_Proc
2639 (Prim : Final_Primitives;
2641 Stmts : List_Id) return Entity_Id
2643 Loc : constant Source_Ptr := Sloc (Typ);
2645 Proc_Name : Entity_Id;
2646 Handler : List_Id := No_List;
2650 if Prim = Finalize_Case then
2651 Formals := New_List;
2652 Type_B := Standard_Boolean;
2655 Formals := New_List (
2656 Make_Parameter_Specification (Loc,
2657 Defining_Identifier => Make_Defining_Identifier (Loc, Name_L),
2659 Out_Present => True,
2661 New_Reference_To (RTE (RE_Finalizable_Ptr), Loc)));
2662 Type_B := Standard_Short_Short_Integer;
2666 Make_Parameter_Specification (Loc,
2667 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
2669 Out_Present => True,
2670 Parameter_Type => New_Reference_To (Typ, Loc)));
2673 Make_Parameter_Specification (Loc,
2674 Defining_Identifier => Make_Defining_Identifier (Loc, Name_B),
2675 Parameter_Type => New_Reference_To (Type_B, Loc)));
2677 if Prim = Finalize_Case or else Prim = Adjust_Case then
2678 Handler := New_List (Make_Handler_For_Ctrl_Operation (Loc));
2682 Make_Defining_Identifier (Loc,
2683 Chars => Make_TSS_Name (Typ, Deep_Name_Of (Prim)));
2686 Make_Subprogram_Body (Loc,
2688 Make_Procedure_Specification (Loc,
2689 Defining_Unit_Name => Proc_Name,
2690 Parameter_Specifications => Formals),
2692 Declarations => Empty_List,
2693 Handled_Statement_Sequence =>
2694 Make_Handled_Sequence_Of_Statements (Loc,
2695 Statements => Stmts,
2696 Exception_Handlers => Handler)));
2701 ---------------------------
2702 -- Make_Deep_Record_Body --
2703 ---------------------------
2705 -- The Deep procedures call the appropriate Controlling proc on the
2706 -- the controller component. In the init case, it also attach the
2707 -- controller to the current finalization list.
2709 function Make_Deep_Record_Body
2710 (Prim : Final_Primitives;
2711 Typ : Entity_Id) return List_Id
2713 Loc : constant Source_Ptr := Sloc (Typ);
2714 Controller_Typ : Entity_Id;
2715 Obj_Ref : constant Node_Id := Make_Identifier (Loc, Name_V);
2716 Controller_Ref : constant Node_Id :=
2717 Make_Selected_Component (Loc,
2720 Make_Identifier (Loc, Name_uController));
2721 Res : constant List_Id := New_List;
2724 if Is_Immutably_Limited_Type (Typ) then
2725 Controller_Typ := RTE (RE_Limited_Record_Controller);
2727 Controller_Typ := RTE (RE_Record_Controller);
2731 when Initialize_Case =>
2732 Append_List_To (Res,
2734 Ref => Controller_Ref,
2735 Typ => Controller_Typ,
2736 Flist_Ref => Make_Identifier (Loc, Name_L),
2737 With_Attach => Make_Identifier (Loc, Name_B)));
2739 -- When the type is also a controlled type by itself,
2740 -- initialize it and attach it to the finalization chain.
2742 if Is_Controlled (Typ) then
2744 Make_Procedure_Call_Statement (Loc,
2745 Name => New_Reference_To (
2746 Find_Prim_Op (Typ, Name_Of (Prim)), Loc),
2747 Parameter_Associations =>
2748 New_List (New_Copy_Tree (Obj_Ref))));
2750 Append_To (Res, Make_Attach_Call (
2751 Obj_Ref => New_Copy_Tree (Obj_Ref),
2752 Flist_Ref => Make_Identifier (Loc, Name_L),
2753 With_Attach => Make_Identifier (Loc, Name_B)));
2757 Append_List_To (Res,
2758 Make_Adjust_Call (Controller_Ref, Controller_Typ,
2759 Make_Identifier (Loc, Name_L),
2760 Make_Identifier (Loc, Name_B)));
2762 -- When the type is also a controlled type by itself,
2763 -- adjust it and attach it to the finalization chain.
2765 if Is_Controlled (Typ) then
2767 Make_Procedure_Call_Statement (Loc,
2768 Name => New_Reference_To (
2769 Find_Prim_Op (Typ, Name_Of (Prim)), Loc),
2770 Parameter_Associations =>
2771 New_List (New_Copy_Tree (Obj_Ref))));
2773 Append_To (Res, Make_Attach_Call (
2774 Obj_Ref => New_Copy_Tree (Obj_Ref),
2775 Flist_Ref => Make_Identifier (Loc, Name_L),
2776 With_Attach => Make_Identifier (Loc, Name_B)));
2779 when Finalize_Case =>
2780 if Is_Controlled (Typ) then
2782 Make_Implicit_If_Statement (Obj_Ref,
2783 Condition => Make_Identifier (Loc, Name_B),
2784 Then_Statements => New_List (
2785 Make_Procedure_Call_Statement (Loc,
2786 Name => New_Reference_To (RTE (RE_Finalize_One), Loc),
2787 Parameter_Associations => New_List (
2788 OK_Convert_To (RTE (RE_Finalizable),
2789 New_Copy_Tree (Obj_Ref))))),
2791 Else_Statements => New_List (
2792 Make_Procedure_Call_Statement (Loc,
2793 Name => New_Reference_To (
2794 Find_Prim_Op (Typ, Name_Of (Prim)), Loc),
2795 Parameter_Associations =>
2796 New_List (New_Copy_Tree (Obj_Ref))))));
2799 Append_List_To (Res,
2800 Make_Final_Call (Controller_Ref, Controller_Typ,
2801 Make_Identifier (Loc, Name_B)));
2804 end Make_Deep_Record_Body;
2806 ----------------------
2807 -- Make_Final_Call --
2808 ----------------------
2810 function Make_Final_Call
2813 With_Detach : Node_Id) return List_Id
2815 Loc : constant Source_Ptr := Sloc (Ref);
2816 Res : constant List_Id := New_List;
2823 if Is_Class_Wide_Type (Typ) then
2824 Utyp := Root_Type (Typ);
2827 elsif Is_Concurrent_Type (Typ) then
2828 Utyp := Corresponding_Record_Type (Typ);
2829 Cref := Convert_Concurrent (Ref, Typ);
2831 elsif Is_Private_Type (Typ)
2832 and then Present (Full_View (Typ))
2833 and then Is_Concurrent_Type (Full_View (Typ))
2835 Utyp := Corresponding_Record_Type (Full_View (Typ));
2836 Cref := Convert_Concurrent (Ref, Full_View (Typ));
2842 Utyp := Underlying_Type (Base_Type (Utyp));
2843 Set_Assignment_OK (Cref);
2845 -- Deal with non-tagged derivation of private views. If the parent is
2846 -- now known to be protected, the finalization routine is the one
2847 -- defined on the corresponding record of the ancestor (corresponding
2848 -- records do not automatically inherit operations, but maybe they
2851 if Is_Untagged_Derivation (Typ) then
2852 if Is_Protected_Type (Typ) then
2853 Utyp := Corresponding_Record_Type (Root_Type (Base_Type (Typ)));
2855 Utyp := Underlying_Type (Root_Type (Base_Type (Typ)));
2858 Cref := Unchecked_Convert_To (Utyp, Cref);
2860 -- We need to set Assignment_OK to prevent problems with unchecked
2861 -- conversions, where we do not want them to be converted back in the
2862 -- case of untagged record derivation (see code in Make_*_Call
2863 -- procedures for similar situations).
2865 Set_Assignment_OK (Cref);
2868 -- If the underlying_type is a subtype, we are dealing with
2869 -- the completion of a private type. We need to access
2870 -- the base type and generate a conversion to it.
2872 if Utyp /= Base_Type (Utyp) then
2873 pragma Assert (Is_Private_Type (Typ));
2874 Utyp := Base_Type (Utyp);
2875 Cref := Unchecked_Convert_To (Utyp, Cref);
2879 -- Deep_Finalize (Ref, With_Detach);
2881 if Has_Controlled_Component (Utyp)
2882 or else Is_Class_Wide_Type (Typ)
2884 if Is_Tagged_Type (Utyp) then
2885 Proc := Find_Prim_Op (Utyp, TSS_Deep_Finalize);
2887 Proc := TSS (Utyp, TSS_Deep_Finalize);
2890 Cref := Convert_View (Proc, Cref);
2893 Make_Procedure_Call_Statement (Loc,
2894 Name => New_Reference_To (Proc, Loc),
2895 Parameter_Associations =>
2896 New_List (Cref, With_Detach)));
2899 -- if With_Detach then
2900 -- Finalize_One (Ref);
2906 Proc := Find_Prim_Op (Utyp, Name_Of (Finalize_Case));
2908 if Chars (With_Detach) = Chars (Standard_True) then
2910 Make_Procedure_Call_Statement (Loc,
2911 Name => New_Reference_To (RTE (RE_Finalize_One), Loc),
2912 Parameter_Associations => New_List (
2913 OK_Convert_To (RTE (RE_Finalizable), Cref))));
2915 elsif Chars (With_Detach) = Chars (Standard_False) then
2917 Make_Procedure_Call_Statement (Loc,
2918 Name => New_Reference_To (Proc, Loc),
2919 Parameter_Associations =>
2920 New_List (Convert_View (Proc, Cref))));
2923 Cref2 := New_Copy_Tree (Cref);
2925 Make_Implicit_If_Statement (Ref,
2926 Condition => With_Detach,
2927 Then_Statements => New_List (
2928 Make_Procedure_Call_Statement (Loc,
2929 Name => New_Reference_To (RTE (RE_Finalize_One), Loc),
2930 Parameter_Associations => New_List (
2931 OK_Convert_To (RTE (RE_Finalizable), Cref)))),
2933 Else_Statements => New_List (
2934 Make_Procedure_Call_Statement (Loc,
2935 Name => New_Reference_To (Proc, Loc),
2936 Parameter_Associations =>
2937 New_List (Convert_View (Proc, Cref2))))));
2942 end Make_Final_Call;
2944 -------------------------------------
2945 -- Make_Handler_For_Ctrl_Operation --
2946 -------------------------------------
2950 -- when E : others =>
2951 -- Raise_From_Controlled_Operation (X => E);
2956 -- raise Program_Error [finalize raised exception];
2958 -- depending on whether Raise_From_Controlled_Operation is available
2960 function Make_Handler_For_Ctrl_Operation
2961 (Loc : Source_Ptr) return Node_Id
2964 -- Choice parameter (for the first case above)
2966 Raise_Node : Node_Id;
2967 -- Procedure call or raise statement
2970 if RTE_Available (RE_Raise_From_Controlled_Operation) then
2972 -- Standard runtime: add choice parameter E, and pass it to
2973 -- Raise_From_Controlled_Operation so that the original exception
2974 -- name and message can be recorded in the exception message for
2977 E_Occ := Make_Defining_Identifier (Loc, Name_E);
2978 Raise_Node := Make_Procedure_Call_Statement (Loc,
2981 RTE (RE_Raise_From_Controlled_Operation), Loc),
2982 Parameter_Associations => New_List (
2983 New_Occurrence_Of (E_Occ, Loc)));
2986 -- Restricted runtime: exception messages are not supported
2989 Raise_Node := Make_Raise_Program_Error (Loc,
2990 Reason => PE_Finalize_Raised_Exception);
2993 return Make_Implicit_Exception_Handler (Loc,
2994 Exception_Choices => New_List (Make_Others_Choice (Loc)),
2995 Choice_Parameter => E_Occ,
2996 Statements => New_List (Raise_Node));
2997 end Make_Handler_For_Ctrl_Operation;
2999 --------------------
3000 -- Make_Init_Call --
3001 --------------------
3003 function Make_Init_Call
3006 Flist_Ref : Node_Id;
3007 With_Attach : Node_Id) return List_Id
3009 Loc : constant Source_Ptr := Sloc (Ref);
3011 Res : constant List_Id := New_List;
3016 Attach : Node_Id := With_Attach;
3019 if Is_Concurrent_Type (Typ) then
3021 Utyp := Corresponding_Record_Type (Typ);
3022 Cref := Convert_Concurrent (Ref, Typ);
3024 elsif Is_Private_Type (Typ)
3025 and then Present (Full_View (Typ))
3026 and then Is_Concurrent_Type (Underlying_Type (Typ))
3029 Utyp := Corresponding_Record_Type (Underlying_Type (Typ));
3030 Cref := Convert_Concurrent (Ref, Underlying_Type (Typ));
3038 Utyp := Underlying_Type (Base_Type (Utyp));
3040 Set_Assignment_OK (Cref);
3042 -- Deal with non-tagged derivation of private views
3044 if Is_Untagged_Derivation (Typ)
3045 and then not Is_Conc
3047 Utyp := Underlying_Type (Root_Type (Base_Type (Typ)));
3048 Cref := Unchecked_Convert_To (Utyp, Cref);
3049 Set_Assignment_OK (Cref);
3050 -- To prevent problems with UC see 1.156 RH ???
3053 -- If the underlying_type is a subtype, we are dealing with
3054 -- the completion of a private type. We need to access
3055 -- the base type and generate a conversion to it.
3057 if Utyp /= Base_Type (Utyp) then
3058 pragma Assert (Is_Private_Type (Typ));
3059 Utyp := Base_Type (Utyp);
3060 Cref := Unchecked_Convert_To (Utyp, Cref);
3063 -- We do not need to attach to one of the Global Final Lists
3064 -- the objects whose type is Finalize_Storage_Only
3066 if Finalize_Storage_Only (Typ)
3067 and then (Global_Flist_Ref (Flist_Ref)
3068 or else Entity (Constant_Value (RTE (RE_Garbage_Collected)))
3071 Attach := Make_Integer_Literal (Loc, 0);
3075 -- Deep_Initialize (Ref, Flist_Ref);
3077 if Has_Controlled_Component (Utyp) then
3078 Proc := TSS (Utyp, Deep_Name_Of (Initialize_Case));
3080 Cref := Convert_View (Proc, Cref, 2);
3083 Make_Procedure_Call_Statement (Loc,
3084 Name => New_Reference_To (Proc, Loc),
3085 Parameter_Associations => New_List (
3091 -- Attach_To_Final_List (Ref, Flist_Ref);
3092 -- Initialize (Ref);
3094 else -- Is_Controlled (Utyp)
3095 Proc := Find_Prim_Op (Utyp, Name_Of (Initialize_Case));
3096 Check_Visibly_Controlled (Initialize_Case, Typ, Proc, Cref);
3098 Cref := Convert_View (Proc, Cref);
3099 Cref2 := New_Copy_Tree (Cref);
3102 Make_Procedure_Call_Statement (Loc,
3103 Name => New_Reference_To (Proc, Loc),
3104 Parameter_Associations => New_List (Cref2)));
3107 Make_Attach_Call (Cref, Flist_Ref, Attach));
3113 --------------------------
3114 -- Make_Transient_Block --
3115 --------------------------
3117 -- If finalization is involved, this function just wraps the instruction
3118 -- into a block whose name is the transient block entity, and then
3119 -- Expand_Cleanup_Actions (called on the expansion of the handled
3120 -- sequence of statements will do the necessary expansions for
3123 function Make_Transient_Block
3125 Action : Node_Id) return Node_Id
3127 Flist : constant Entity_Id := Finalization_Chain_Entity (Current_Scope);
3128 Decls : constant List_Id := New_List;
3129 Par : constant Node_Id := Parent (Action);
3130 Instrs : constant List_Id := New_List (Action);
3134 -- Case where only secondary stack use is involved
3136 if VM_Target = No_VM
3137 and then Uses_Sec_Stack (Current_Scope)
3139 and then Nkind (Action) /= N_Simple_Return_Statement
3140 and then Nkind (Par) /= N_Exception_Handler
3147 S := Scope (Current_Scope);
3151 -- At the outer level, no need to release the sec stack
3153 if S = Standard_Standard then
3154 Set_Uses_Sec_Stack (Current_Scope, False);
3157 -- In a function, only release the sec stack if the
3158 -- function does not return on the sec stack otherwise
3159 -- the result may be lost. The caller is responsible for
3162 elsif K = E_Function then
3163 Set_Uses_Sec_Stack (Current_Scope, False);
3165 if not Requires_Transient_Scope (Etype (S)) then
3166 Set_Uses_Sec_Stack (S, True);
3167 Check_Restriction (No_Secondary_Stack, Action);
3172 -- In a loop or entry we should install a block encompassing
3173 -- all the construct. For now just release right away.
3175 elsif K = E_Loop or else K = E_Entry then
3178 -- In a procedure or a block, we release on exit of the
3179 -- procedure or block. ??? memory leak can be created by
3182 elsif K = E_Procedure
3185 Set_Uses_Sec_Stack (S, True);
3186 Check_Restriction (No_Secondary_Stack, Action);
3187 Set_Uses_Sec_Stack (Current_Scope, False);
3197 -- Insert actions stuck in the transient scopes as well as all
3198 -- freezing nodes needed by those actions
3200 Insert_Actions_In_Scope_Around (Action);
3203 Last_Inserted : Node_Id := Prev (Action);
3205 if Present (Last_Inserted) then
3206 Freeze_All (First_Entity (Current_Scope), Last_Inserted);
3211 Make_Block_Statement (Loc,
3212 Identifier => New_Reference_To (Current_Scope, Loc),
3213 Declarations => Decls,
3214 Handled_Statement_Sequence =>
3215 Make_Handled_Sequence_Of_Statements (Loc, Statements => Instrs),
3216 Has_Created_Identifier => True);
3218 -- When the transient scope was established, we pushed the entry for
3219 -- the transient scope onto the scope stack, so that the scope was
3220 -- active for the installation of finalizable entities etc. Now we
3221 -- must remove this entry, since we have constructed a proper block.
3226 end Make_Transient_Block;
3228 ------------------------
3229 -- Needs_Finalization --
3230 ------------------------
3232 function Needs_Finalization (T : Entity_Id) return Boolean is
3234 function Has_Some_Controlled_Component (Rec : Entity_Id) return Boolean;
3235 -- If type is not frozen yet, check explicitly among its components,
3236 -- because the Has_Controlled_Component flag is not necessarily set.
3238 -----------------------------------
3239 -- Has_Some_Controlled_Component --
3240 -----------------------------------
3242 function Has_Some_Controlled_Component
3243 (Rec : Entity_Id) return Boolean
3248 if Has_Controlled_Component (Rec) then
3251 elsif not Is_Frozen (Rec) then
3252 if Is_Record_Type (Rec) then
3253 Comp := First_Entity (Rec);
3255 while Present (Comp) loop
3256 if not Is_Type (Comp)
3257 and then Needs_Finalization (Etype (Comp))
3267 elsif Is_Array_Type (Rec) then
3268 return Needs_Finalization (Component_Type (Rec));
3271 return Has_Controlled_Component (Rec);
3276 end Has_Some_Controlled_Component;
3278 -- Start of processing for Needs_Finalization
3283 -- Class-wide types must be treated as controlled and therefore
3284 -- requiring finalization (because they may be extended with an
3285 -- extension that has controlled components.
3287 (Is_Class_Wide_Type (T)
3289 -- However, avoid treating class-wide types as controlled if
3290 -- finalization is not available and in particular CIL value
3291 -- types never have finalization).
3293 and then not In_Finalization_Root (T)
3294 and then not Restriction_Active (No_Finalization)
3295 and then not Is_Value_Type (Etype (T)))
3297 -- Controlled types always need finalization
3299 or else Is_Controlled (T)
3300 or else Has_Some_Controlled_Component (T)
3302 -- For concurrent types, test the corresponding record type
3304 or else (Is_Concurrent_Type (T)
3305 and then Present (Corresponding_Record_Type (T))
3306 and then Needs_Finalization (Corresponding_Record_Type (T)));
3307 end Needs_Finalization;
3309 ------------------------
3310 -- Node_To_Be_Wrapped --
3311 ------------------------
3313 function Node_To_Be_Wrapped return Node_Id is
3315 return Scope_Stack.Table (Scope_Stack.Last).Node_To_Be_Wrapped;
3316 end Node_To_Be_Wrapped;
3318 ----------------------------
3319 -- Set_Node_To_Be_Wrapped --
3320 ----------------------------
3322 procedure Set_Node_To_Be_Wrapped (N : Node_Id) is
3324 Scope_Stack.Table (Scope_Stack.Last).Node_To_Be_Wrapped := N;
3325 end Set_Node_To_Be_Wrapped;
3327 ----------------------------------
3328 -- Store_After_Actions_In_Scope --
3329 ----------------------------------
3331 procedure Store_After_Actions_In_Scope (L : List_Id) is
3332 SE : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
3335 if Present (SE.Actions_To_Be_Wrapped_After) then
3336 Insert_List_Before_And_Analyze (
3337 First (SE.Actions_To_Be_Wrapped_After), L);
3340 SE.Actions_To_Be_Wrapped_After := L;
3342 if Is_List_Member (SE.Node_To_Be_Wrapped) then
3343 Set_Parent (L, Parent (SE.Node_To_Be_Wrapped));
3345 Set_Parent (L, SE.Node_To_Be_Wrapped);
3350 end Store_After_Actions_In_Scope;
3352 -----------------------------------
3353 -- Store_Before_Actions_In_Scope --
3354 -----------------------------------
3356 procedure Store_Before_Actions_In_Scope (L : List_Id) is
3357 SE : Scope_Stack_Entry renames Scope_Stack.Table (Scope_Stack.Last);
3360 if Present (SE.Actions_To_Be_Wrapped_Before) then
3361 Insert_List_After_And_Analyze (
3362 Last (SE.Actions_To_Be_Wrapped_Before), L);
3365 SE.Actions_To_Be_Wrapped_Before := L;
3367 if Is_List_Member (SE.Node_To_Be_Wrapped) then
3368 Set_Parent (L, Parent (SE.Node_To_Be_Wrapped));
3370 Set_Parent (L, SE.Node_To_Be_Wrapped);
3375 end Store_Before_Actions_In_Scope;
3377 --------------------------------
3378 -- Wrap_Transient_Declaration --
3379 --------------------------------
3381 -- If a transient scope has been established during the processing of the
3382 -- Expression of an Object_Declaration, it is not possible to wrap the
3383 -- declaration into a transient block as usual case, otherwise the object
3384 -- would be itself declared in the wrong scope. Therefore, all entities (if
3385 -- any) defined in the transient block are moved to the proper enclosing
3386 -- scope, furthermore, if they are controlled variables they are finalized
3387 -- right after the declaration. The finalization list of the transient
3388 -- scope is defined as a renaming of the enclosing one so during their
3389 -- initialization they will be attached to the proper finalization
3390 -- list. For instance, the following declaration :
3392 -- X : Typ := F (G (A), G (B));
3394 -- (where G(A) and G(B) return controlled values, expanded as _v1 and _v2)
3395 -- is expanded into :
3397 -- _local_final_list_1 : Finalizable_Ptr;
3398 -- X : Typ := [ complex Expression-Action ];
3399 -- Finalize_One(_v1);
3400 -- Finalize_One (_v2);
3402 procedure Wrap_Transient_Declaration (N : Node_Id) is
3404 LC : Entity_Id := Empty;
3406 Loc : constant Source_Ptr := Sloc (N);
3407 First_Decl_Loc : Source_Ptr;
3408 Enclosing_S : Entity_Id;
3410 Next_N : constant Node_Id := Next (N);
3414 Enclosing_S := Scope (S);
3416 -- Insert Actions kept in the Scope stack
3418 Insert_Actions_In_Scope_Around (N);
3420 -- If the declaration is consuming some secondary stack, mark the
3421 -- Enclosing scope appropriately.
3423 Uses_SS := Uses_Sec_Stack (S);
3426 -- Create a List controller and rename the final list to be its
3427 -- internal final pointer:
3428 -- Lxxx : Simple_List_Controller;
3429 -- Fxxx : Finalizable_Ptr renames Lxxx.F;
3431 if Present (Finalization_Chain_Entity (S)) then
3432 LC := Make_Temporary (Loc, 'L');
3434 -- Use the Sloc of the first declaration of N's containing list, to
3435 -- maintain monotonicity of source-line stepping during debugging.
3437 First_Decl_Loc := Sloc (First (List_Containing (N)));
3440 Make_Object_Declaration (First_Decl_Loc,
3441 Defining_Identifier => LC,
3442 Object_Definition =>
3444 (RTE (RE_Simple_List_Controller), First_Decl_Loc)),
3446 Make_Object_Renaming_Declaration (First_Decl_Loc,
3447 Defining_Identifier => Finalization_Chain_Entity (S),
3449 New_Reference_To (RTE (RE_Finalizable_Ptr), First_Decl_Loc),
3451 Make_Selected_Component (Loc,
3452 Prefix => New_Reference_To (LC, First_Decl_Loc),
3453 Selector_Name => Make_Identifier (First_Decl_Loc, Name_F))));
3455 -- Put the declaration at the beginning of the declaration part
3456 -- to make sure it will be before all other actions that have been
3457 -- inserted before N.
3459 Insert_List_Before_And_Analyze (First (List_Containing (N)), Nodes);
3461 -- Generate the Finalization calls by finalizing the list controller
3462 -- right away. It will be re-finalized on scope exit but it doesn't
3463 -- matter. It cannot be done when the call initializes a renaming
3464 -- object though because in this case, the object becomes a pointer
3465 -- to the temporary and thus increases its life span. Ditto if this
3466 -- is a renaming of a component of an expression (such as a function
3469 -- Note that there is a problem if an actual in the call needs
3470 -- finalization, because in that case the call itself is the master,
3471 -- and the actual should be finalized on return from the call ???
3473 if Nkind (N) = N_Object_Renaming_Declaration
3474 and then Needs_Finalization (Etype (Defining_Identifier (N)))
3478 elsif Nkind (N) = N_Object_Renaming_Declaration
3480 Nkind_In (Renamed_Object (Defining_Identifier (N)),
3481 N_Selected_Component,
3482 N_Indexed_Component)
3485 (Etype (Prefix (Renamed_Object (Defining_Identifier (N)))))
3492 (Ref => New_Reference_To (LC, Loc),
3494 With_Detach => New_Reference_To (Standard_False, Loc));
3496 if Present (Next_N) then
3497 Insert_List_Before_And_Analyze (Next_N, Nodes);
3499 Append_List_To (List_Containing (N), Nodes);
3504 -- Put the local entities back in the enclosing scope, and set the
3505 -- Is_Public flag appropriately.
3507 Transfer_Entities (S, Enclosing_S);
3509 -- Mark the enclosing dynamic scope so that the sec stack will be
3510 -- released upon its exit unless this is a function that returns on
3511 -- the sec stack in which case this will be done by the caller.
3513 if VM_Target = No_VM and then Uses_SS then
3514 S := Enclosing_Dynamic_Scope (S);
3516 if Ekind (S) = E_Function
3517 and then Requires_Transient_Scope (Etype (S))
3521 Set_Uses_Sec_Stack (S);
3522 Check_Restriction (No_Secondary_Stack, N);
3525 end Wrap_Transient_Declaration;
3527 -------------------------------
3528 -- Wrap_Transient_Expression --
3529 -------------------------------
3531 -- Insert actions before <Expression>:
3533 -- (lines marked with <CTRL> are expanded only in presence of Controlled
3534 -- objects needing finalization)
3538 -- _M : constant Mark_Id := SS_Mark;
3539 -- Local_Final_List : System.FI.Finalizable_Ptr; <CTRL>
3541 -- procedure _Clean is
3544 -- System.FI.Finalize_List (Local_Final_List); <CTRL>
3550 -- _E := <Expression>;
3555 -- then expression is replaced by _E
3557 procedure Wrap_Transient_Expression (N : Node_Id) is
3558 Loc : constant Source_Ptr := Sloc (N);
3559 E : constant Entity_Id := Make_Temporary (Loc, 'E', N);
3560 Etyp : constant Entity_Id := Etype (N);
3561 Expr : constant Node_Id := Relocate_Node (N);
3564 Insert_Actions (N, New_List (
3565 Make_Object_Declaration (Loc,
3566 Defining_Identifier => E,
3567 Object_Definition => New_Reference_To (Etyp, Loc)),
3569 Make_Transient_Block (Loc,
3571 Make_Assignment_Statement (Loc,
3572 Name => New_Reference_To (E, Loc),
3573 Expression => Expr))));
3575 Rewrite (N, New_Reference_To (E, Loc));
3576 Analyze_And_Resolve (N, Etyp);
3577 end Wrap_Transient_Expression;
3579 ------------------------------
3580 -- Wrap_Transient_Statement --
3581 ------------------------------
3583 -- Transform <Instruction> into
3585 -- (lines marked with <CTRL> are expanded only in presence of Controlled
3586 -- objects needing finalization)
3589 -- _M : Mark_Id := SS_Mark;
3590 -- Local_Final_List : System.FI.Finalizable_Ptr ; <CTRL>
3592 -- procedure _Clean is
3595 -- System.FI.Finalize_List (Local_Final_List); <CTRL>
3606 procedure Wrap_Transient_Statement (N : Node_Id) is
3607 Loc : constant Source_Ptr := Sloc (N);
3608 New_Statement : constant Node_Id := Relocate_Node (N);
3611 Rewrite (N, Make_Transient_Block (Loc, New_Statement));
3613 -- With the scope stack back to normal, we can call analyze on the
3614 -- resulting block. At this point, the transient scope is being
3615 -- treated like a perfectly normal scope, so there is nothing
3616 -- special about it.
3618 -- Note: Wrap_Transient_Statement is called with the node already
3619 -- analyzed (i.e. Analyzed (N) is True). This is important, since
3620 -- otherwise we would get a recursive processing of the node when
3621 -- we do this Analyze call.
3624 end Wrap_Transient_Statement;