* lto.c (do_stream_out): Add PART parameter; open dump file.
[official-gcc.git] / gcc / ada / exp_disp.adb
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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- E X P _ D I S P --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2018, Free Software Foundation, Inc. --
10 -- --
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. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Expander; use Expander;
33 with Exp_Atag; use Exp_Atag;
34 with Exp_Ch6; use Exp_Ch6;
35 with Exp_CG; use Exp_CG;
36 with Exp_Dbug; use Exp_Dbug;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Freeze; use Freeze;
40 with Ghost; use Ghost;
41 with Itypes; use Itypes;
42 with Layout; use Layout;
43 with Nlists; use Nlists;
44 with Nmake; use Nmake;
45 with Namet; use Namet;
46 with Opt; use Opt;
47 with Output; use Output;
48 with Restrict; use Restrict;
49 with Rident; use Rident;
50 with Rtsfind; use Rtsfind;
51 with Sem; use Sem;
52 with Sem_Aux; use Sem_Aux;
53 with Sem_Ch6; use Sem_Ch6;
54 with Sem_Ch7; use Sem_Ch7;
55 with Sem_Ch8; use Sem_Ch8;
56 with Sem_Disp; use Sem_Disp;
57 with Sem_Eval; use Sem_Eval;
58 with Sem_Res; use Sem_Res;
59 with Sem_Type; use Sem_Type;
60 with Sem_Util; use Sem_Util;
61 with Sinfo; use Sinfo;
62 with Sinput; use Sinput;
63 with Snames; use Snames;
64 with Stand; use Stand;
65 with Stringt; use Stringt;
66 with SCIL_LL; use SCIL_LL;
67 with Tbuild; use Tbuild;
69 package body Exp_Disp is
71 -----------------------
72 -- Local Subprograms --
73 -----------------------
75 function Default_Prim_Op_Position (E : Entity_Id) return Uint;
76 -- Ada 2005 (AI-251): Returns the fixed position in the dispatch table
77 -- of the default primitive operations.
79 function Has_DT (Typ : Entity_Id) return Boolean;
80 pragma Inline (Has_DT);
81 -- Returns true if we generate a dispatch table for tagged type Typ
83 function Is_Predefined_Dispatching_Alias (Prim : Entity_Id) return Boolean;
84 -- Returns true if Prim is not a predefined dispatching primitive but it is
85 -- an alias of a predefined dispatching primitive (i.e. through a renaming)
87 function New_Value (From : Node_Id) return Node_Id;
88 -- From is the original Expression. New_Value is equivalent to a call to
89 -- Duplicate_Subexpr with an explicit dereference when From is an access
90 -- parameter.
92 function Original_View_In_Visible_Part (Typ : Entity_Id) return Boolean;
93 -- Check if the type has a private view or if the public view appears in
94 -- the visible part of a package spec.
96 function Prim_Op_Kind
97 (Prim : Entity_Id;
98 Typ : Entity_Id) return Node_Id;
99 -- Ada 2005 (AI-345): Determine the primitive operation kind of Prim
100 -- according to its type Typ. Return a reference to an RE_Prim_Op_Kind
101 -- enumeration value.
103 function Tagged_Kind (T : Entity_Id) return Node_Id;
104 -- Ada 2005 (AI-345): Determine the tagged kind of T and return a reference
105 -- to an RE_Tagged_Kind enumeration value.
107 ----------------------
108 -- Apply_Tag_Checks --
109 ----------------------
111 procedure Apply_Tag_Checks (Call_Node : Node_Id) is
112 Loc : constant Source_Ptr := Sloc (Call_Node);
113 Ctrl_Arg : constant Node_Id := Controlling_Argument (Call_Node);
114 Ctrl_Typ : constant Entity_Id := Base_Type (Etype (Ctrl_Arg));
115 Param_List : constant List_Id := Parameter_Associations (Call_Node);
117 Subp : Entity_Id;
118 CW_Typ : Entity_Id;
119 Param : Node_Id;
120 Typ : Entity_Id;
121 Eq_Prim_Op : Entity_Id := Empty;
123 begin
124 if No_Run_Time_Mode then
125 Error_Msg_CRT ("tagged types", Call_Node);
126 return;
127 end if;
129 -- Apply_Tag_Checks is called directly from the semantics, so we
130 -- need a check to see whether expansion is active before proceeding.
131 -- In addition, there is no need to expand the call when compiling
132 -- under restriction No_Dispatching_Calls; the semantic analyzer has
133 -- previously notified the violation of this restriction.
135 if not Expander_Active
136 or else Restriction_Active (No_Dispatching_Calls)
137 then
138 return;
139 end if;
141 -- Set subprogram. If this is an inherited operation that was
142 -- overridden, the body that is being called is its alias.
144 Subp := Entity (Name (Call_Node));
146 if Present (Alias (Subp))
147 and then Is_Inherited_Operation (Subp)
148 and then No (DTC_Entity (Subp))
149 then
150 Subp := Alias (Subp);
151 end if;
153 -- Definition of the class-wide type and the tagged type
155 -- If the controlling argument is itself a tag rather than a tagged
156 -- object, then use the class-wide type associated with the subprogram's
157 -- controlling type. This case can occur when a call to an inherited
158 -- primitive has an actual that originated from a default parameter
159 -- given by a tag-indeterminate call and when there is no other
160 -- controlling argument providing the tag (AI-239 requires dispatching).
161 -- This capability of dispatching directly by tag is also needed by the
162 -- implementation of AI-260 (for the generic dispatching constructors).
164 if Ctrl_Typ = RTE (RE_Tag)
165 or else (RTE_Available (RE_Interface_Tag)
166 and then Ctrl_Typ = RTE (RE_Interface_Tag))
167 then
168 CW_Typ := Class_Wide_Type (Find_Dispatching_Type (Subp));
170 -- Class_Wide_Type is applied to the expressions used to initialize
171 -- CW_Typ, to ensure that CW_Typ always denotes a class-wide type, since
172 -- there are cases where the controlling type is resolved to a specific
173 -- type (such as for designated types of arguments such as CW'Access).
175 elsif Is_Access_Type (Ctrl_Typ) then
176 CW_Typ := Class_Wide_Type (Designated_Type (Ctrl_Typ));
178 else
179 CW_Typ := Class_Wide_Type (Ctrl_Typ);
180 end if;
182 Typ := Find_Specific_Type (CW_Typ);
184 if not Is_Limited_Type (Typ) then
185 Eq_Prim_Op := Find_Prim_Op (Typ, Name_Op_Eq);
186 end if;
188 -- Dispatching call to C++ primitive
190 if Is_CPP_Class (Typ) then
191 null;
193 -- Dispatching call to Ada primitive
195 elsif Present (Param_List) then
197 -- Generate the Tag checks when appropriate
199 Param := First_Actual (Call_Node);
200 while Present (Param) loop
202 -- No tag check with itself
204 if Param = Ctrl_Arg then
205 null;
207 -- No tag check for parameter whose type is neither tagged nor
208 -- access to tagged (for access parameters)
210 elsif No (Find_Controlling_Arg (Param)) then
211 null;
213 -- No tag check for function dispatching on result if the
214 -- Tag given by the context is this one
216 elsif Find_Controlling_Arg (Param) = Ctrl_Arg then
217 null;
219 -- "=" is the only dispatching operation allowed to get operands
220 -- with incompatible tags (it just returns false). We use
221 -- Duplicate_Subexpr_Move_Checks instead of calling Relocate_Node
222 -- because the value will be duplicated to check the tags.
224 elsif Subp = Eq_Prim_Op then
225 null;
227 -- No check in presence of suppress flags
229 elsif Tag_Checks_Suppressed (Etype (Param))
230 or else (Is_Access_Type (Etype (Param))
231 and then Tag_Checks_Suppressed
232 (Designated_Type (Etype (Param))))
233 then
234 null;
236 -- Optimization: no tag checks if the parameters are identical
238 elsif Is_Entity_Name (Param)
239 and then Is_Entity_Name (Ctrl_Arg)
240 and then Entity (Param) = Entity (Ctrl_Arg)
241 then
242 null;
244 -- Now we need to generate the Tag check
246 else
247 -- Generate code for tag equality check
249 -- Perhaps should have Checks.Apply_Tag_Equality_Check???
251 Insert_Action (Ctrl_Arg,
252 Make_Implicit_If_Statement (Call_Node,
253 Condition =>
254 Make_Op_Ne (Loc,
255 Left_Opnd =>
256 Make_Selected_Component (Loc,
257 Prefix => New_Value (Ctrl_Arg),
258 Selector_Name =>
259 New_Occurrence_Of
260 (First_Tag_Component (Typ), Loc)),
262 Right_Opnd =>
263 Make_Selected_Component (Loc,
264 Prefix =>
265 Unchecked_Convert_To (Typ, New_Value (Param)),
266 Selector_Name =>
267 New_Occurrence_Of
268 (First_Tag_Component (Typ), Loc))),
270 Then_Statements =>
271 New_List (New_Constraint_Error (Loc))));
272 end if;
274 Next_Actual (Param);
275 end loop;
276 end if;
277 end Apply_Tag_Checks;
279 ------------------------
280 -- Building_Static_DT --
281 ------------------------
283 function Building_Static_DT (Typ : Entity_Id) return Boolean is
284 Root_Typ : Entity_Id := Root_Type (Typ);
285 Static_DT : Boolean;
287 begin
288 -- Handle private types
290 if Present (Full_View (Root_Typ)) then
291 Root_Typ := Full_View (Root_Typ);
292 end if;
294 Static_DT :=
295 Building_Static_Dispatch_Tables
296 and then Is_Library_Level_Tagged_Type (Typ)
298 -- If the type is derived from a CPP class we cannot statically
299 -- build the dispatch tables because we must inherit primitives
300 -- from the CPP side.
302 and then not Is_CPP_Class (Root_Typ);
304 if not Static_DT then
305 Check_Restriction (Static_Dispatch_Tables, Typ);
306 end if;
308 return Static_DT;
309 end Building_Static_DT;
311 ----------------------------------
312 -- Building_Static_Secondary_DT --
313 ----------------------------------
315 function Building_Static_Secondary_DT (Typ : Entity_Id) return Boolean is
316 Full_Typ : Entity_Id := Typ;
317 Root_Typ : Entity_Id := Root_Type (Typ);
318 Static_DT : Boolean;
320 begin
321 -- Handle private types
323 if Present (Full_View (Typ)) then
324 Full_Typ := Full_View (Typ);
325 end if;
327 if Present (Full_View (Root_Typ)) then
328 Root_Typ := Full_View (Root_Typ);
329 end if;
331 Static_DT :=
332 Building_Static_DT (Full_Typ)
333 and then not Is_Interface (Full_Typ)
334 and then Has_Interfaces (Full_Typ)
335 and then (Full_Typ = Root_Typ
336 or else not Is_Variable_Size_Record (Etype (Full_Typ)));
338 if not Static_DT
339 and then not Is_Interface (Full_Typ)
340 and then Has_Interfaces (Full_Typ)
341 then
342 Check_Restriction (Static_Dispatch_Tables, Typ);
343 end if;
345 return Static_DT;
346 end Building_Static_Secondary_DT;
348 ----------------------------------
349 -- Build_Static_Dispatch_Tables --
350 ----------------------------------
352 procedure Build_Static_Dispatch_Tables (N : Entity_Id) is
353 Target_List : List_Id;
355 procedure Build_Dispatch_Tables (List : List_Id);
356 -- Build the static dispatch table of tagged types found in the list of
357 -- declarations. The generated nodes are added at the end of Target_List
359 procedure Build_Package_Dispatch_Tables (N : Node_Id);
360 -- Build static dispatch tables associated with package declaration N
362 ---------------------------
363 -- Build_Dispatch_Tables --
364 ---------------------------
366 procedure Build_Dispatch_Tables (List : List_Id) is
367 D : Node_Id;
369 begin
370 D := First (List);
371 while Present (D) loop
373 -- Handle nested packages and package bodies recursively. The
374 -- generated code is placed on the Target_List established for
375 -- the enclosing compilation unit.
377 if Nkind (D) = N_Package_Declaration then
378 Build_Package_Dispatch_Tables (D);
380 elsif Nkind (D) = N_Package_Body then
381 Build_Dispatch_Tables (Declarations (D));
383 elsif Nkind (D) = N_Package_Body_Stub
384 and then Present (Library_Unit (D))
385 then
386 Build_Dispatch_Tables
387 (Declarations (Proper_Body (Unit (Library_Unit (D)))));
389 -- Handle full type declarations and derivations of library level
390 -- tagged types
392 elsif Nkind_In (D, N_Full_Type_Declaration,
393 N_Derived_Type_Definition)
394 and then Is_Library_Level_Tagged_Type (Defining_Entity (D))
395 and then Ekind (Defining_Entity (D)) /= E_Record_Subtype
396 and then not Is_Private_Type (Defining_Entity (D))
397 then
398 -- We do not generate dispatch tables for the internal types
399 -- created for a type extension with unknown discriminants
400 -- The needed information is shared with the source type,
401 -- See Expand_N_Record_Extension.
403 if Is_Underlying_Record_View (Defining_Entity (D))
404 or else
405 (not Comes_From_Source (Defining_Entity (D))
406 and then
407 Has_Unknown_Discriminants (Etype (Defining_Entity (D)))
408 and then
409 not Comes_From_Source
410 (First_Subtype (Defining_Entity (D))))
411 then
412 null;
413 else
414 Insert_List_After_And_Analyze (Last (Target_List),
415 Make_DT (Defining_Entity (D)));
416 end if;
418 -- Handle private types of library level tagged types. We must
419 -- exchange the private and full-view to ensure the correct
420 -- expansion. If the full view is a synchronized type ignore
421 -- the type because the table will be built for the corresponding
422 -- record type, that has its own declaration.
424 elsif (Nkind (D) = N_Private_Type_Declaration
425 or else Nkind (D) = N_Private_Extension_Declaration)
426 and then Present (Full_View (Defining_Entity (D)))
427 then
428 declare
429 E1 : constant Entity_Id := Defining_Entity (D);
430 E2 : constant Entity_Id := Full_View (E1);
432 begin
433 if Is_Library_Level_Tagged_Type (E2)
434 and then Ekind (E2) /= E_Record_Subtype
435 and then not Is_Concurrent_Type (E2)
436 then
437 Exchange_Declarations (E1);
438 Insert_List_After_And_Analyze (Last (Target_List),
439 Make_DT (E1));
440 Exchange_Declarations (E2);
441 end if;
442 end;
443 end if;
445 Next (D);
446 end loop;
447 end Build_Dispatch_Tables;
449 -----------------------------------
450 -- Build_Package_Dispatch_Tables --
451 -----------------------------------
453 procedure Build_Package_Dispatch_Tables (N : Node_Id) is
454 Spec : constant Node_Id := Specification (N);
455 Id : constant Entity_Id := Defining_Entity (N);
456 Vis_Decls : constant List_Id := Visible_Declarations (Spec);
457 Priv_Decls : constant List_Id := Private_Declarations (Spec);
459 begin
460 Push_Scope (Id);
462 if Present (Priv_Decls) then
463 Build_Dispatch_Tables (Vis_Decls);
464 Build_Dispatch_Tables (Priv_Decls);
466 elsif Present (Vis_Decls) then
467 Build_Dispatch_Tables (Vis_Decls);
468 end if;
470 Pop_Scope;
471 end Build_Package_Dispatch_Tables;
473 -- Start of processing for Build_Static_Dispatch_Tables
475 begin
476 if not Expander_Active
477 or else not Tagged_Type_Expansion
478 then
479 return;
480 end if;
482 if Nkind (N) = N_Package_Declaration then
483 declare
484 Spec : constant Node_Id := Specification (N);
485 Vis_Decls : constant List_Id := Visible_Declarations (Spec);
486 Priv_Decls : constant List_Id := Private_Declarations (Spec);
488 begin
489 if Present (Priv_Decls)
490 and then Is_Non_Empty_List (Priv_Decls)
491 then
492 Target_List := Priv_Decls;
494 elsif not Present (Vis_Decls) then
495 Target_List := New_List;
496 Set_Private_Declarations (Spec, Target_List);
497 else
498 Target_List := Vis_Decls;
499 end if;
501 Build_Package_Dispatch_Tables (N);
502 end;
504 else pragma Assert (Nkind (N) = N_Package_Body);
505 Target_List := Declarations (N);
506 Build_Dispatch_Tables (Target_List);
507 end if;
508 end Build_Static_Dispatch_Tables;
510 ------------------------------
511 -- Convert_Tag_To_Interface --
512 ------------------------------
514 function Convert_Tag_To_Interface
515 (Typ : Entity_Id;
516 Expr : Node_Id) return Node_Id
518 Loc : constant Source_Ptr := Sloc (Expr);
519 Anon_Type : Entity_Id;
520 Result : Node_Id;
522 begin
523 pragma Assert (Is_Class_Wide_Type (Typ)
524 and then Is_Interface (Typ)
525 and then
526 ((Nkind (Expr) = N_Selected_Component
527 and then Is_Tag (Entity (Selector_Name (Expr))))
528 or else
529 (Nkind (Expr) = N_Function_Call
530 and then RTE_Available (RE_Displace)
531 and then Entity (Name (Expr)) = RTE (RE_Displace))));
533 Anon_Type := Create_Itype (E_Anonymous_Access_Type, Expr);
534 Set_Directly_Designated_Type (Anon_Type, Typ);
535 Set_Etype (Anon_Type, Anon_Type);
536 Set_Can_Never_Be_Null (Anon_Type);
538 -- Decorate the size and alignment attributes of the anonymous access
539 -- type, as required by the back end.
541 Layout_Type (Anon_Type);
543 if Nkind (Expr) = N_Selected_Component
544 and then Is_Tag (Entity (Selector_Name (Expr)))
545 then
546 Result :=
547 Make_Explicit_Dereference (Loc,
548 Unchecked_Convert_To (Anon_Type,
549 Make_Attribute_Reference (Loc,
550 Prefix => Expr,
551 Attribute_Name => Name_Address)));
552 else
553 Result :=
554 Make_Explicit_Dereference (Loc,
555 Unchecked_Convert_To (Anon_Type, Expr));
556 end if;
558 return Result;
559 end Convert_Tag_To_Interface;
561 -------------------
562 -- CPP_Num_Prims --
563 -------------------
565 function CPP_Num_Prims (Typ : Entity_Id) return Nat is
566 CPP_Typ : Entity_Id;
567 Tag_Comp : Entity_Id;
569 begin
570 if not Is_Tagged_Type (Typ)
571 or else not Is_CPP_Class (Root_Type (Typ))
572 then
573 return 0;
575 else
576 CPP_Typ := Enclosing_CPP_Parent (Typ);
577 Tag_Comp := First_Tag_Component (CPP_Typ);
579 -- If number of primitives already set in the tag component, use it
581 if Present (Tag_Comp)
582 and then DT_Entry_Count (Tag_Comp) /= No_Uint
583 then
584 return UI_To_Int (DT_Entry_Count (Tag_Comp));
586 -- Otherwise, count the primitives of the enclosing CPP type
588 else
589 declare
590 Count : Nat := 0;
591 Elmt : Elmt_Id;
593 begin
594 Elmt := First_Elmt (Primitive_Operations (CPP_Typ));
595 while Present (Elmt) loop
596 Count := Count + 1;
597 Next_Elmt (Elmt);
598 end loop;
600 return Count;
601 end;
602 end if;
603 end if;
604 end CPP_Num_Prims;
606 ------------------------------
607 -- Default_Prim_Op_Position --
608 ------------------------------
610 function Default_Prim_Op_Position (E : Entity_Id) return Uint is
611 TSS_Name : TSS_Name_Type;
613 begin
614 Get_Name_String (Chars (E));
615 TSS_Name :=
616 TSS_Name_Type
617 (Name_Buffer (Name_Len - TSS_Name'Length + 1 .. Name_Len));
619 if Chars (E) = Name_uSize then
620 return Uint_1;
622 elsif TSS_Name = TSS_Stream_Read then
623 return Uint_2;
625 elsif TSS_Name = TSS_Stream_Write then
626 return Uint_3;
628 elsif TSS_Name = TSS_Stream_Input then
629 return Uint_4;
631 elsif TSS_Name = TSS_Stream_Output then
632 return Uint_5;
634 elsif Chars (E) = Name_Op_Eq then
635 return Uint_6;
637 elsif Chars (E) = Name_uAssign then
638 return Uint_7;
640 elsif TSS_Name = TSS_Deep_Adjust then
641 return Uint_8;
643 elsif TSS_Name = TSS_Deep_Finalize then
644 return Uint_9;
646 -- In VM targets unconditionally allow obtaining the position associated
647 -- with predefined interface primitives since in these platforms any
648 -- tagged type has these primitives.
650 elsif Ada_Version >= Ada_2005 or else not Tagged_Type_Expansion then
651 if Chars (E) = Name_uDisp_Asynchronous_Select then
652 return Uint_10;
654 elsif Chars (E) = Name_uDisp_Conditional_Select then
655 return Uint_11;
657 elsif Chars (E) = Name_uDisp_Get_Prim_Op_Kind then
658 return Uint_12;
660 elsif Chars (E) = Name_uDisp_Get_Task_Id then
661 return Uint_13;
663 elsif Chars (E) = Name_uDisp_Requeue then
664 return Uint_14;
666 elsif Chars (E) = Name_uDisp_Timed_Select then
667 return Uint_15;
668 end if;
669 end if;
671 raise Program_Error;
672 end Default_Prim_Op_Position;
674 ----------------------
675 -- Elab_Flag_Needed --
676 ----------------------
678 function Elab_Flag_Needed (Typ : Entity_Id) return Boolean is
679 begin
680 return Ada_Version >= Ada_2005
681 and then not Is_Interface (Typ)
682 and then Has_Interfaces (Typ)
683 and then not Building_Static_DT (Typ);
684 end Elab_Flag_Needed;
686 -----------------------------
687 -- Expand_Dispatching_Call --
688 -----------------------------
690 procedure Expand_Dispatching_Call (Call_Node : Node_Id) is
691 Loc : constant Source_Ptr := Sloc (Call_Node);
692 Call_Typ : constant Entity_Id := Etype (Call_Node);
694 Ctrl_Arg : constant Node_Id := Controlling_Argument (Call_Node);
695 Ctrl_Typ : constant Entity_Id := Base_Type (Etype (Ctrl_Arg));
696 Param_List : constant List_Id := Parameter_Associations (Call_Node);
698 Subp : Entity_Id;
699 CW_Typ : Entity_Id;
700 New_Call : Node_Id;
701 New_Call_Name : Node_Id;
702 New_Params : List_Id := No_List;
703 Param : Node_Id;
704 Res_Typ : Entity_Id;
705 Subp_Ptr_Typ : Entity_Id;
706 Subp_Typ : Entity_Id;
707 Typ : Entity_Id;
708 Eq_Prim_Op : Entity_Id := Empty;
709 Controlling_Tag : Node_Id;
711 procedure Build_Class_Wide_Check;
712 -- If the denoted subprogram has a class-wide precondition, generate a
713 -- check using that precondition before the dispatching call, because
714 -- this is the only class-wide precondition that applies to the call.
716 function New_Value (From : Node_Id) return Node_Id;
717 -- From is the original Expression. New_Value is equivalent to a call
718 -- to Duplicate_Subexpr with an explicit dereference when From is an
719 -- access parameter.
721 ----------------------------
722 -- Build_Class_Wide_Check --
723 ----------------------------
725 procedure Build_Class_Wide_Check is
726 function Replace_Formals (N : Node_Id) return Traverse_Result;
727 -- Replace occurrences of the formals of the subprogram by the
728 -- corresponding actuals in the call, given that this check is
729 -- performed outside of the body of the subprogram.
731 ---------------------
732 -- Replace_Formals --
733 ---------------------
735 function Replace_Formals (N : Node_Id) return Traverse_Result is
736 begin
737 if Is_Entity_Name (N)
738 and then Present (Entity (N))
739 and then Is_Formal (Entity (N))
740 then
741 declare
742 A : Node_Id;
743 F : Entity_Id;
745 begin
746 F := First_Formal (Subp);
747 A := First_Actual (Call_Node);
748 while Present (F) loop
749 if F = Entity (N) then
750 Rewrite (N, New_Copy_Tree (A));
752 -- If the formal is class-wide, and thus not a
753 -- controlling argument, preserve its type because
754 -- it may appear in a nested call with a class-wide
755 -- parameter.
757 if Is_Class_Wide_Type (Etype (F)) then
758 Set_Etype (N, Etype (F));
760 -- Conversely, if this is a controlling argument
761 -- (in a dispatching call in the condition) that is a
762 -- dereference, the source is an access-to-class-wide
763 -- type, so preserve the dispatching nature of the
764 -- call in the rewritten condition.
766 elsif Nkind (Parent (N)) = N_Explicit_Dereference
767 and then Is_Controlling_Actual (Parent (N))
768 then
769 Set_Controlling_Argument (Parent (Parent (N)),
770 Parent (N));
771 end if;
773 exit;
774 end if;
776 Next_Formal (F);
777 Next_Actual (A);
778 end loop;
779 end;
780 end if;
782 return OK;
783 end Replace_Formals;
785 procedure Update is new Traverse_Proc (Replace_Formals);
787 -- Local variables
789 Str_Loc : constant String := Build_Location_String (Loc);
791 Cond : Node_Id;
792 Msg : Node_Id;
793 Prec : Node_Id;
795 -- Start of processing for Build_Class_Wide_Check
797 begin
799 -- Locate class-wide precondition, if any
801 if Present (Contract (Subp))
802 and then Present (Pre_Post_Conditions (Contract (Subp)))
803 then
804 Prec := Pre_Post_Conditions (Contract (Subp));
806 while Present (Prec) loop
807 exit when Pragma_Name (Prec) = Name_Precondition
808 and then Class_Present (Prec);
809 Prec := Next_Pragma (Prec);
810 end loop;
812 if No (Prec) then
813 return;
814 end if;
816 -- The expression for the precondition is analyzed within the
817 -- generated pragma. The message text is the last parameter of
818 -- the generated pragma, indicating source of precondition.
820 Cond :=
821 New_Copy_Tree
822 (Expression (First (Pragma_Argument_Associations (Prec))));
823 Update (Cond);
825 -- Build message indicating the failed precondition and the
826 -- dispatching call that caused it.
828 Msg := Expression (Last (Pragma_Argument_Associations (Prec)));
829 Name_Len := 0;
830 Append (Global_Name_Buffer, Strval (Msg));
831 Append (Global_Name_Buffer, " in dispatching call at ");
832 Append (Global_Name_Buffer, Str_Loc);
833 Msg := Make_String_Literal (Loc, Name_Buffer (1 .. Name_Len));
835 Insert_Action (Call_Node,
836 Make_If_Statement (Loc,
837 Condition => Make_Op_Not (Loc, Cond),
838 Then_Statements => New_List (
839 Make_Procedure_Call_Statement (Loc,
840 Name =>
841 New_Occurrence_Of (RTE (RE_Raise_Assert_Failure), Loc),
842 Parameter_Associations => New_List (Msg)))));
843 end if;
844 end Build_Class_Wide_Check;
846 ---------------
847 -- New_Value --
848 ---------------
850 function New_Value (From : Node_Id) return Node_Id is
851 Res : constant Node_Id := Duplicate_Subexpr (From);
852 begin
853 if Is_Access_Type (Etype (From)) then
854 return
855 Make_Explicit_Dereference (Sloc (From),
856 Prefix => Res);
857 else
858 return Res;
859 end if;
860 end New_Value;
862 -- Local variables
864 New_Node : Node_Id;
865 SCIL_Node : Node_Id := Empty;
866 SCIL_Related_Node : Node_Id := Call_Node;
868 -- Start of processing for Expand_Dispatching_Call
870 begin
871 if No_Run_Time_Mode then
872 Error_Msg_CRT ("tagged types", Call_Node);
873 return;
874 end if;
876 -- Expand_Dispatching_Call is called directly from the semantics, so we
877 -- only proceed if the expander is active.
879 if not Expander_Active
881 -- And there is no need to expand the call if we are compiling under
882 -- restriction No_Dispatching_Calls; the semantic analyzer has
883 -- previously notified the violation of this restriction.
885 or else Restriction_Active (No_Dispatching_Calls)
887 -- No action needed if the dispatching call has been already expanded
889 or else Is_Expanded_Dispatching_Call (Name (Call_Node))
890 then
891 return;
892 end if;
894 -- Set subprogram. If this is an inherited operation that was
895 -- overridden, the body that is being called is its alias.
897 Subp := Entity (Name (Call_Node));
899 if Present (Alias (Subp))
900 and then Is_Inherited_Operation (Subp)
901 and then No (DTC_Entity (Subp))
902 then
903 Subp := Alias (Subp);
904 end if;
906 Build_Class_Wide_Check;
908 -- Definition of the class-wide type and the tagged type
910 -- If the controlling argument is itself a tag rather than a tagged
911 -- object, then use the class-wide type associated with the subprogram's
912 -- controlling type. This case can occur when a call to an inherited
913 -- primitive has an actual that originated from a default parameter
914 -- given by a tag-indeterminate call and when there is no other
915 -- controlling argument providing the tag (AI-239 requires dispatching).
916 -- This capability of dispatching directly by tag is also needed by the
917 -- implementation of AI-260 (for the generic dispatching constructors).
919 if Ctrl_Typ = RTE (RE_Tag)
920 or else (RTE_Available (RE_Interface_Tag)
921 and then Ctrl_Typ = RTE (RE_Interface_Tag))
922 then
923 CW_Typ := Class_Wide_Type (Find_Dispatching_Type (Subp));
925 -- Class_Wide_Type is applied to the expressions used to initialize
926 -- CW_Typ, to ensure that CW_Typ always denotes a class-wide type, since
927 -- there are cases where the controlling type is resolved to a specific
928 -- type (such as for designated types of arguments such as CW'Access).
930 elsif Is_Access_Type (Ctrl_Typ) then
931 CW_Typ := Class_Wide_Type (Designated_Type (Ctrl_Typ));
933 else
934 CW_Typ := Class_Wide_Type (Ctrl_Typ);
935 end if;
937 Typ := Find_Specific_Type (CW_Typ);
939 if not Is_Limited_Type (Typ) then
940 Eq_Prim_Op := Find_Prim_Op (Typ, Name_Op_Eq);
941 end if;
943 -- Dispatching call to C++ primitive. Create a new parameter list
944 -- with no tag checks.
946 New_Params := New_List;
948 if Is_CPP_Class (Typ) then
949 Param := First_Actual (Call_Node);
950 while Present (Param) loop
951 Append_To (New_Params, Relocate_Node (Param));
952 Next_Actual (Param);
953 end loop;
955 -- Dispatching call to Ada primitive
957 elsif Present (Param_List) then
958 Apply_Tag_Checks (Call_Node);
960 Param := First_Actual (Call_Node);
961 while Present (Param) loop
963 -- Cases in which we may have generated run-time checks. Note that
964 -- we strip any qualification from Param before comparing with the
965 -- already-stripped controlling argument.
967 if Unqualify (Param) = Ctrl_Arg or else Subp = Eq_Prim_Op then
968 Append_To (New_Params,
969 Duplicate_Subexpr_Move_Checks (Param));
971 elsif Nkind (Parent (Param)) /= N_Parameter_Association
972 or else not Is_Accessibility_Actual (Parent (Param))
973 then
974 Append_To (New_Params, Relocate_Node (Param));
975 end if;
977 Next_Actual (Param);
978 end loop;
979 end if;
981 -- Generate the appropriate subprogram pointer type
983 if Etype (Subp) = Typ then
984 Res_Typ := CW_Typ;
985 else
986 Res_Typ := Etype (Subp);
987 end if;
989 Subp_Typ := Create_Itype (E_Subprogram_Type, Call_Node);
990 Subp_Ptr_Typ := Create_Itype (E_Access_Subprogram_Type, Call_Node);
991 Set_Etype (Subp_Typ, Res_Typ);
992 Set_Returns_By_Ref (Subp_Typ, Returns_By_Ref (Subp));
993 Set_Convention (Subp_Typ, Convention (Subp));
995 -- Notify gigi that the designated type is a dispatching primitive
997 Set_Is_Dispatch_Table_Entity (Subp_Typ);
999 -- Create a new list of parameters which is a copy of the old formal
1000 -- list including the creation of a new set of matching entities.
1002 declare
1003 Old_Formal : Entity_Id := First_Formal (Subp);
1004 New_Formal : Entity_Id;
1005 Extra : Entity_Id := Empty;
1007 begin
1008 if Present (Old_Formal) then
1009 New_Formal := New_Copy (Old_Formal);
1010 Set_First_Entity (Subp_Typ, New_Formal);
1011 Param := First_Actual (Call_Node);
1013 loop
1014 Set_Scope (New_Formal, Subp_Typ);
1016 -- Change all the controlling argument types to be class-wide
1017 -- to avoid a recursion in dispatching.
1019 if Is_Controlling_Formal (New_Formal) then
1020 Set_Etype (New_Formal, Etype (Param));
1021 end if;
1023 -- If the type of the formal is an itype, there was code here
1024 -- introduced in 1998 in revision 1.46, to create a new itype
1025 -- by copy. This seems useless, and in fact leads to semantic
1026 -- errors when the itype is the completion of a type derived
1027 -- from a private type.
1029 Extra := New_Formal;
1030 Next_Formal (Old_Formal);
1031 exit when No (Old_Formal);
1033 Link_Entities (New_Formal, New_Copy (Old_Formal));
1034 Next_Entity (New_Formal);
1035 Next_Actual (Param);
1036 end loop;
1038 Unlink_Next_Entity (New_Formal);
1039 Set_Last_Entity (Subp_Typ, Extra);
1040 end if;
1042 -- Now that the explicit formals have been duplicated, any extra
1043 -- formals needed by the subprogram must be created.
1045 if Present (Extra) then
1046 Set_Extra_Formal (Extra, Empty);
1047 end if;
1049 Create_Extra_Formals (Subp_Typ);
1050 end;
1052 -- Complete description of pointer type, including size information, as
1053 -- must be done with itypes to prevent order-of-elaboration anomalies
1054 -- in gigi.
1056 Set_Etype (Subp_Ptr_Typ, Subp_Ptr_Typ);
1057 Set_Directly_Designated_Type (Subp_Ptr_Typ, Subp_Typ);
1058 Set_Convention (Subp_Ptr_Typ, Convention (Subp_Typ));
1059 Layout_Type (Subp_Ptr_Typ);
1061 -- If the controlling argument is a value of type Ada.Tag or an abstract
1062 -- interface class-wide type then use it directly. Otherwise, the tag
1063 -- must be extracted from the controlling object.
1065 if Ctrl_Typ = RTE (RE_Tag)
1066 or else (RTE_Available (RE_Interface_Tag)
1067 and then Ctrl_Typ = RTE (RE_Interface_Tag))
1068 then
1069 Controlling_Tag := Duplicate_Subexpr (Ctrl_Arg);
1071 -- Extract the tag from an unchecked type conversion. Done to avoid
1072 -- the expansion of additional code just to obtain the value of such
1073 -- tag because the current management of interface type conversions
1074 -- generates in some cases this unchecked type conversion with the
1075 -- tag of the object (see Expand_Interface_Conversion).
1077 elsif Nkind (Ctrl_Arg) = N_Unchecked_Type_Conversion
1078 and then
1079 (Etype (Expression (Ctrl_Arg)) = RTE (RE_Tag)
1080 or else
1081 (RTE_Available (RE_Interface_Tag)
1082 and then
1083 Etype (Expression (Ctrl_Arg)) = RTE (RE_Interface_Tag)))
1084 then
1085 Controlling_Tag := Duplicate_Subexpr (Expression (Ctrl_Arg));
1087 -- Ada 2005 (AI-251): Abstract interface class-wide type
1089 elsif Is_Interface (Ctrl_Typ)
1090 and then Is_Class_Wide_Type (Ctrl_Typ)
1091 then
1092 Controlling_Tag := Duplicate_Subexpr (Ctrl_Arg);
1094 else
1095 Controlling_Tag :=
1096 Make_Selected_Component (Loc,
1097 Prefix => Duplicate_Subexpr_Move_Checks (Ctrl_Arg),
1098 Selector_Name => New_Occurrence_Of (DTC_Entity (Subp), Loc));
1099 end if;
1101 -- Handle dispatching calls to predefined primitives
1103 if Is_Predefined_Dispatching_Operation (Subp)
1104 or else Is_Predefined_Dispatching_Alias (Subp)
1105 then
1106 Build_Get_Predefined_Prim_Op_Address (Loc,
1107 Tag_Node => Controlling_Tag,
1108 Position => DT_Position (Subp),
1109 New_Node => New_Node);
1111 -- Handle dispatching calls to user-defined primitives
1113 else
1114 Build_Get_Prim_Op_Address (Loc,
1115 Typ => Underlying_Type (Find_Dispatching_Type (Subp)),
1116 Tag_Node => Controlling_Tag,
1117 Position => DT_Position (Subp),
1118 New_Node => New_Node);
1119 end if;
1121 New_Call_Name :=
1122 Unchecked_Convert_To (Subp_Ptr_Typ, New_Node);
1124 -- Generate the SCIL node for this dispatching call. Done now because
1125 -- attribute SCIL_Controlling_Tag must be set after the new call name
1126 -- is built to reference the nodes that will see the SCIL backend
1127 -- (because Build_Get_Prim_Op_Address generates an unchecked type
1128 -- conversion which relocates the controlling tag node).
1130 if Generate_SCIL then
1131 SCIL_Node := Make_SCIL_Dispatching_Call (Sloc (Call_Node));
1132 Set_SCIL_Entity (SCIL_Node, Typ);
1133 Set_SCIL_Target_Prim (SCIL_Node, Subp);
1135 -- Common case: the controlling tag is the tag of an object
1136 -- (for example, obj.tag)
1138 if Nkind (Controlling_Tag) = N_Selected_Component then
1139 Set_SCIL_Controlling_Tag (SCIL_Node, Controlling_Tag);
1141 -- Handle renaming of selected component
1143 elsif Nkind (Controlling_Tag) = N_Identifier
1144 and then Nkind (Parent (Entity (Controlling_Tag))) =
1145 N_Object_Renaming_Declaration
1146 and then Nkind (Name (Parent (Entity (Controlling_Tag)))) =
1147 N_Selected_Component
1148 then
1149 Set_SCIL_Controlling_Tag (SCIL_Node,
1150 Name (Parent (Entity (Controlling_Tag))));
1152 -- If the controlling tag is an identifier, the SCIL node references
1153 -- the corresponding object or parameter declaration
1155 elsif Nkind (Controlling_Tag) = N_Identifier
1156 and then Nkind_In (Parent (Entity (Controlling_Tag)),
1157 N_Object_Declaration,
1158 N_Parameter_Specification)
1159 then
1160 Set_SCIL_Controlling_Tag (SCIL_Node,
1161 Parent (Entity (Controlling_Tag)));
1163 -- If the controlling tag is a dereference, the SCIL node references
1164 -- the corresponding object or parameter declaration
1166 elsif Nkind (Controlling_Tag) = N_Explicit_Dereference
1167 and then Nkind (Prefix (Controlling_Tag)) = N_Identifier
1168 and then Nkind_In (Parent (Entity (Prefix (Controlling_Tag))),
1169 N_Object_Declaration,
1170 N_Parameter_Specification)
1171 then
1172 Set_SCIL_Controlling_Tag (SCIL_Node,
1173 Parent (Entity (Prefix (Controlling_Tag))));
1175 -- For a direct reference of the tag of the type the SCIL node
1176 -- references the internal object declaration containing the tag
1177 -- of the type.
1179 elsif Nkind (Controlling_Tag) = N_Attribute_Reference
1180 and then Attribute_Name (Controlling_Tag) = Name_Tag
1181 then
1182 Set_SCIL_Controlling_Tag (SCIL_Node,
1183 Parent
1184 (Node
1185 (First_Elmt
1186 (Access_Disp_Table (Entity (Prefix (Controlling_Tag)))))));
1188 -- Interfaces are not supported. For now we leave the SCIL node
1189 -- decorated with the Controlling_Tag. More work needed here???
1191 elsif Is_Interface (Etype (Controlling_Tag)) then
1192 Set_SCIL_Controlling_Tag (SCIL_Node, Controlling_Tag);
1194 else
1195 pragma Assert (False);
1196 null;
1197 end if;
1198 end if;
1200 if Nkind (Call_Node) = N_Function_Call then
1201 New_Call :=
1202 Make_Function_Call (Loc,
1203 Name => New_Call_Name,
1204 Parameter_Associations => New_Params);
1206 -- If this is a dispatching "=", we must first compare the tags so
1207 -- we generate: x.tag = y.tag and then x = y
1209 if Subp = Eq_Prim_Op then
1210 Param := First_Actual (Call_Node);
1211 New_Call :=
1212 Make_And_Then (Loc,
1213 Left_Opnd =>
1214 Make_Op_Eq (Loc,
1215 Left_Opnd =>
1216 Make_Selected_Component (Loc,
1217 Prefix => New_Value (Param),
1218 Selector_Name =>
1219 New_Occurrence_Of (First_Tag_Component (Typ),
1220 Loc)),
1222 Right_Opnd =>
1223 Make_Selected_Component (Loc,
1224 Prefix =>
1225 Unchecked_Convert_To (Typ,
1226 New_Value (Next_Actual (Param))),
1227 Selector_Name =>
1228 New_Occurrence_Of
1229 (First_Tag_Component (Typ), Loc))),
1230 Right_Opnd => New_Call);
1232 SCIL_Related_Node := Right_Opnd (New_Call);
1233 end if;
1235 else
1236 New_Call :=
1237 Make_Procedure_Call_Statement (Loc,
1238 Name => New_Call_Name,
1239 Parameter_Associations => New_Params);
1240 end if;
1242 -- Register the dispatching call in the call graph nodes table
1244 Register_CG_Node (Call_Node);
1246 Rewrite (Call_Node, New_Call);
1248 -- Associate the SCIL node of this dispatching call
1250 if Generate_SCIL then
1251 Set_SCIL_Node (SCIL_Related_Node, SCIL_Node);
1252 end if;
1254 -- Suppress all checks during the analysis of the expanded code to avoid
1255 -- the generation of spurious warnings under ZFP run-time.
1257 Analyze_And_Resolve (Call_Node, Call_Typ, Suppress => All_Checks);
1258 end Expand_Dispatching_Call;
1260 ---------------------------------
1261 -- Expand_Interface_Conversion --
1262 ---------------------------------
1264 procedure Expand_Interface_Conversion (N : Node_Id) is
1265 function Underlying_Record_Type (Typ : Entity_Id) return Entity_Id;
1266 -- Return the underlying record type of Typ
1268 ----------------------------
1269 -- Underlying_Record_Type --
1270 ----------------------------
1272 function Underlying_Record_Type (Typ : Entity_Id) return Entity_Id is
1273 E : Entity_Id := Typ;
1275 begin
1276 -- Handle access types
1278 if Is_Access_Type (E) then
1279 E := Directly_Designated_Type (E);
1280 end if;
1282 -- Handle class-wide types. This conversion can appear explicitly in
1283 -- the source code. Example: I'Class (Obj)
1285 if Is_Class_Wide_Type (E) then
1286 E := Root_Type (E);
1287 end if;
1289 -- If the target type is a tagged synchronized type, the dispatch
1290 -- table info is in the corresponding record type.
1292 if Is_Concurrent_Type (E) then
1293 E := Corresponding_Record_Type (E);
1294 end if;
1296 -- Handle private types
1298 E := Underlying_Type (E);
1300 -- Handle subtypes
1302 return Base_Type (E);
1303 end Underlying_Record_Type;
1305 -- Local variables
1307 Loc : constant Source_Ptr := Sloc (N);
1308 Etyp : constant Entity_Id := Etype (N);
1309 Operand : constant Node_Id := Expression (N);
1310 Operand_Typ : Entity_Id := Etype (Operand);
1311 Func : Node_Id;
1312 Iface_Typ : constant Entity_Id := Underlying_Record_Type (Etype (N));
1313 Iface_Tag : Entity_Id;
1314 Is_Static : Boolean;
1316 -- Start of processing for Expand_Interface_Conversion
1318 begin
1319 -- Freeze the entity associated with the target interface to have
1320 -- available the attribute Access_Disp_Table.
1322 Freeze_Before (N, Iface_Typ);
1324 -- Ada 2005 (AI-345): Handle synchronized interface type derivations
1326 if Is_Concurrent_Type (Operand_Typ) then
1327 Operand_Typ := Base_Type (Corresponding_Record_Type (Operand_Typ));
1328 end if;
1330 -- No displacement of the pointer to the object needed when the type of
1331 -- the operand is not an interface type and the interface is one of
1332 -- its parent types (since they share the primary dispatch table).
1334 declare
1335 Opnd : Entity_Id := Operand_Typ;
1337 begin
1338 if Is_Access_Type (Opnd) then
1339 Opnd := Designated_Type (Opnd);
1340 end if;
1342 if not Is_Interface (Opnd)
1343 and then Is_Ancestor (Iface_Typ, Opnd, Use_Full_View => True)
1344 then
1345 return;
1346 end if;
1347 end;
1349 -- Evaluate if we can statically displace the pointer to the object
1351 declare
1352 Opnd_Typ : constant Node_Id := Underlying_Record_Type (Operand_Typ);
1354 begin
1355 Is_Static :=
1356 not Is_Interface (Opnd_Typ)
1357 and then Interface_Present_In_Ancestor
1358 (Typ => Opnd_Typ,
1359 Iface => Iface_Typ)
1360 and then (Etype (Opnd_Typ) = Opnd_Typ
1361 or else not
1362 Is_Variable_Size_Record (Etype (Opnd_Typ)));
1363 end;
1365 if not Tagged_Type_Expansion then
1366 return;
1368 -- A static conversion to an interface type that is not class-wide is
1369 -- curious but legal if the interface operation is a null procedure.
1370 -- If the operation is abstract it will be rejected later.
1372 elsif Is_Static
1373 and then Is_Interface (Etype (N))
1374 and then not Is_Class_Wide_Type (Etype (N))
1375 and then Comes_From_Source (N)
1376 then
1377 Rewrite (N, Unchecked_Convert_To (Etype (N), N));
1378 Analyze (N);
1379 return;
1380 end if;
1382 if not Is_Static then
1384 -- Give error if configurable run-time and Displace not available
1386 if not RTE_Available (RE_Displace) then
1387 Error_Msg_CRT ("dynamic interface conversion", N);
1388 return;
1389 end if;
1391 -- Handle conversion of access-to-class-wide interface types. Target
1392 -- can be an access to an object or an access to another class-wide
1393 -- interface (see -1- and -2- in the following example):
1395 -- type Iface1_Ref is access all Iface1'Class;
1396 -- type Iface2_Ref is access all Iface1'Class;
1398 -- Acc1 : Iface1_Ref := new ...
1399 -- Obj : Obj_Ref := Obj_Ref (Acc); -- 1
1400 -- Acc2 : Iface2_Ref := Iface2_Ref (Acc); -- 2
1402 if Is_Access_Type (Operand_Typ) then
1403 Rewrite (N,
1404 Unchecked_Convert_To (Etype (N),
1405 Make_Function_Call (Loc,
1406 Name => New_Occurrence_Of (RTE (RE_Displace), Loc),
1407 Parameter_Associations => New_List (
1409 Unchecked_Convert_To (RTE (RE_Address),
1410 Relocate_Node (Expression (N))),
1412 New_Occurrence_Of
1413 (Node (First_Elmt (Access_Disp_Table (Iface_Typ))),
1414 Loc)))));
1416 Analyze (N);
1417 return;
1418 end if;
1420 Rewrite (N,
1421 Make_Function_Call (Loc,
1422 Name => New_Occurrence_Of (RTE (RE_Displace), Loc),
1423 Parameter_Associations => New_List (
1424 Make_Attribute_Reference (Loc,
1425 Prefix => Relocate_Node (Expression (N)),
1426 Attribute_Name => Name_Address),
1428 New_Occurrence_Of
1429 (Node (First_Elmt (Access_Disp_Table (Iface_Typ))),
1430 Loc))));
1432 Analyze (N);
1434 -- If target is a class-wide interface, change the type of the data
1435 -- returned by IW_Convert to indicate this is a dispatching call.
1437 declare
1438 New_Itype : Entity_Id;
1440 begin
1441 New_Itype := Create_Itype (E_Anonymous_Access_Type, N);
1442 Set_Etype (New_Itype, New_Itype);
1443 Set_Directly_Designated_Type (New_Itype, Etyp);
1445 Rewrite (N,
1446 Make_Explicit_Dereference (Loc,
1447 Prefix =>
1448 Unchecked_Convert_To (New_Itype, Relocate_Node (N))));
1449 Analyze (N);
1450 Freeze_Itype (New_Itype, N);
1452 return;
1453 end;
1454 end if;
1456 Iface_Tag := Find_Interface_Tag (Operand_Typ, Iface_Typ);
1457 pragma Assert (Iface_Tag /= Empty);
1459 -- Keep separate access types to interfaces because one internal
1460 -- function is used to handle the null value (see following comments)
1462 if not Is_Access_Type (Etype (N)) then
1464 -- Statically displace the pointer to the object to reference the
1465 -- component containing the secondary dispatch table.
1467 Rewrite (N,
1468 Convert_Tag_To_Interface (Class_Wide_Type (Iface_Typ),
1469 Make_Selected_Component (Loc,
1470 Prefix => Relocate_Node (Expression (N)),
1471 Selector_Name => New_Occurrence_Of (Iface_Tag, Loc))));
1473 else
1474 -- Build internal function to handle the case in which the actual is
1475 -- null. If the actual is null returns null because no displacement
1476 -- is required; otherwise performs a type conversion that will be
1477 -- expanded in the code that returns the value of the displaced
1478 -- actual. That is:
1480 -- function Func (O : Address) return Iface_Typ is
1481 -- type Op_Typ is access all Operand_Typ;
1482 -- Aux : Op_Typ := To_Op_Typ (O);
1483 -- begin
1484 -- if O = Null_Address then
1485 -- return null;
1486 -- else
1487 -- return Iface_Typ!(Aux.Iface_Tag'Address);
1488 -- end if;
1489 -- end Func;
1491 declare
1492 Desig_Typ : Entity_Id;
1493 Fent : Entity_Id;
1494 New_Typ_Decl : Node_Id;
1495 Stats : List_Id;
1497 begin
1498 Desig_Typ := Etype (Expression (N));
1500 if Is_Access_Type (Desig_Typ) then
1501 Desig_Typ :=
1502 Available_View (Directly_Designated_Type (Desig_Typ));
1503 end if;
1505 if Is_Concurrent_Type (Desig_Typ) then
1506 Desig_Typ := Base_Type (Corresponding_Record_Type (Desig_Typ));
1507 end if;
1509 New_Typ_Decl :=
1510 Make_Full_Type_Declaration (Loc,
1511 Defining_Identifier => Make_Temporary (Loc, 'T'),
1512 Type_Definition =>
1513 Make_Access_To_Object_Definition (Loc,
1514 All_Present => True,
1515 Null_Exclusion_Present => False,
1516 Constant_Present => False,
1517 Subtype_Indication =>
1518 New_Occurrence_Of (Desig_Typ, Loc)));
1520 Stats := New_List (
1521 Make_Simple_Return_Statement (Loc,
1522 Unchecked_Convert_To (Etype (N),
1523 Make_Attribute_Reference (Loc,
1524 Prefix =>
1525 Make_Selected_Component (Loc,
1526 Prefix =>
1527 Unchecked_Convert_To
1528 (Defining_Identifier (New_Typ_Decl),
1529 Make_Identifier (Loc, Name_uO)),
1530 Selector_Name =>
1531 New_Occurrence_Of (Iface_Tag, Loc)),
1532 Attribute_Name => Name_Address))));
1534 -- If the type is null-excluding, no need for the null branch.
1535 -- Otherwise we need to check for it and return null.
1537 if not Can_Never_Be_Null (Etype (N)) then
1538 Stats := New_List (
1539 Make_If_Statement (Loc,
1540 Condition =>
1541 Make_Op_Eq (Loc,
1542 Left_Opnd => Make_Identifier (Loc, Name_uO),
1543 Right_Opnd => New_Occurrence_Of
1544 (RTE (RE_Null_Address), Loc)),
1546 Then_Statements => New_List (
1547 Make_Simple_Return_Statement (Loc, Make_Null (Loc))),
1548 Else_Statements => Stats));
1549 end if;
1551 Fent := Make_Temporary (Loc, 'F');
1552 Func :=
1553 Make_Subprogram_Body (Loc,
1554 Specification =>
1555 Make_Function_Specification (Loc,
1556 Defining_Unit_Name => Fent,
1558 Parameter_Specifications => New_List (
1559 Make_Parameter_Specification (Loc,
1560 Defining_Identifier =>
1561 Make_Defining_Identifier (Loc, Name_uO),
1562 Parameter_Type =>
1563 New_Occurrence_Of (RTE (RE_Address), Loc))),
1565 Result_Definition =>
1566 New_Occurrence_Of (Etype (N), Loc)),
1568 Declarations => New_List (New_Typ_Decl),
1570 Handled_Statement_Sequence =>
1571 Make_Handled_Sequence_Of_Statements (Loc, Stats));
1573 -- Place function body before the expression containing the
1574 -- conversion. We suppress all checks because the body of the
1575 -- internally generated function already takes care of the case
1576 -- in which the actual is null; therefore there is no need to
1577 -- double check that the pointer is not null when the program
1578 -- executes the alternative that performs the type conversion).
1580 Insert_Action (N, Func, Suppress => All_Checks);
1582 if Is_Access_Type (Etype (Expression (N))) then
1584 -- Generate: Func (Address!(Expression))
1586 Rewrite (N,
1587 Make_Function_Call (Loc,
1588 Name => New_Occurrence_Of (Fent, Loc),
1589 Parameter_Associations => New_List (
1590 Unchecked_Convert_To (RTE (RE_Address),
1591 Relocate_Node (Expression (N))))));
1593 else
1594 -- Generate: Func (Operand_Typ!(Expression)'Address)
1596 Rewrite (N,
1597 Make_Function_Call (Loc,
1598 Name => New_Occurrence_Of (Fent, Loc),
1599 Parameter_Associations => New_List (
1600 Make_Attribute_Reference (Loc,
1601 Prefix => Unchecked_Convert_To (Operand_Typ,
1602 Relocate_Node (Expression (N))),
1603 Attribute_Name => Name_Address))));
1604 end if;
1605 end;
1606 end if;
1608 Analyze (N);
1609 end Expand_Interface_Conversion;
1611 ------------------------------
1612 -- Expand_Interface_Actuals --
1613 ------------------------------
1615 procedure Expand_Interface_Actuals (Call_Node : Node_Id) is
1616 Actual : Node_Id;
1617 Actual_Dup : Node_Id;
1618 Actual_Typ : Entity_Id;
1619 Anon : Entity_Id;
1620 Conversion : Node_Id;
1621 Formal : Entity_Id;
1622 Formal_Typ : Entity_Id;
1623 Subp : Entity_Id;
1624 Formal_DDT : Entity_Id := Empty; -- initialize to prevent warning
1625 Actual_DDT : Entity_Id := Empty; -- initialize to prevent warning
1627 begin
1628 -- This subprogram is called directly from the semantics, so we need a
1629 -- check to see whether expansion is active before proceeding.
1631 if not Expander_Active then
1632 return;
1633 end if;
1635 -- Call using access to subprogram with explicit dereference
1637 if Nkind (Name (Call_Node)) = N_Explicit_Dereference then
1638 Subp := Etype (Name (Call_Node));
1640 -- Call using selected component
1642 elsif Nkind (Name (Call_Node)) = N_Selected_Component then
1643 Subp := Entity (Selector_Name (Name (Call_Node)));
1645 -- Call using direct name
1647 else
1648 Subp := Entity (Name (Call_Node));
1649 end if;
1651 -- Ada 2005 (AI-251): Look for interface type formals to force "this"
1652 -- displacement
1654 Formal := First_Formal (Subp);
1655 Actual := First_Actual (Call_Node);
1656 while Present (Formal) loop
1657 Formal_Typ := Etype (Formal);
1659 if Ekind (Formal_Typ) = E_Record_Type_With_Private then
1660 Formal_Typ := Full_View (Formal_Typ);
1661 end if;
1663 if Is_Access_Type (Formal_Typ) then
1664 Formal_DDT := Directly_Designated_Type (Formal_Typ);
1665 end if;
1667 Actual_Typ := Etype (Actual);
1669 if Is_Access_Type (Actual_Typ) then
1670 Actual_DDT := Directly_Designated_Type (Actual_Typ);
1671 end if;
1673 if Is_Interface (Formal_Typ)
1674 and then Is_Class_Wide_Type (Formal_Typ)
1675 then
1676 -- No need to displace the pointer if the type of the actual
1677 -- coincides with the type of the formal.
1679 if Actual_Typ = Formal_Typ then
1680 null;
1682 -- No need to displace the pointer if the interface type is a
1683 -- parent of the type of the actual because in this case the
1684 -- interface primitives are located in the primary dispatch table.
1686 elsif Is_Ancestor (Formal_Typ, Actual_Typ,
1687 Use_Full_View => True)
1688 then
1689 null;
1691 -- Implicit conversion to the class-wide formal type to force the
1692 -- displacement of the pointer.
1694 else
1695 -- Normally, expansion of actuals for calls to build-in-place
1696 -- functions happens as part of Expand_Actuals, but in this
1697 -- case the call will be wrapped in a conversion and soon after
1698 -- expanded further to handle the displacement for a class-wide
1699 -- interface conversion, so if this is a BIP call then we need
1700 -- to handle it now.
1702 if Is_Build_In_Place_Function_Call (Actual) then
1703 Make_Build_In_Place_Call_In_Anonymous_Context (Actual);
1704 end if;
1706 Conversion := Convert_To (Formal_Typ, Relocate_Node (Actual));
1707 Rewrite (Actual, Conversion);
1708 Analyze_And_Resolve (Actual, Formal_Typ);
1709 end if;
1711 -- Access to class-wide interface type
1713 elsif Is_Access_Type (Formal_Typ)
1714 and then Is_Interface (Formal_DDT)
1715 and then Is_Class_Wide_Type (Formal_DDT)
1716 and then Interface_Present_In_Ancestor
1717 (Typ => Actual_DDT,
1718 Iface => Etype (Formal_DDT))
1719 then
1720 -- Handle attributes 'Access and 'Unchecked_Access
1722 if Nkind (Actual) = N_Attribute_Reference
1723 and then
1724 (Attribute_Name (Actual) = Name_Access
1725 or else Attribute_Name (Actual) = Name_Unchecked_Access)
1726 then
1727 -- This case must have been handled by the analysis and
1728 -- expansion of 'Access. The only exception is when types
1729 -- match and no further expansion is required.
1731 pragma Assert (Base_Type (Etype (Prefix (Actual)))
1732 = Base_Type (Formal_DDT));
1733 null;
1735 -- No need to displace the pointer if the type of the actual
1736 -- coincides with the type of the formal.
1738 elsif Actual_DDT = Formal_DDT then
1739 null;
1741 -- No need to displace the pointer if the interface type is
1742 -- a parent of the type of the actual because in this case the
1743 -- interface primitives are located in the primary dispatch table.
1745 elsif Is_Ancestor (Formal_DDT, Actual_DDT,
1746 Use_Full_View => True)
1747 then
1748 null;
1750 else
1751 Actual_Dup := Relocate_Node (Actual);
1753 if From_Limited_With (Actual_Typ) then
1755 -- If the type of the actual parameter comes from a limited
1756 -- with_clause and the nonlimited view is already available,
1757 -- we replace the anonymous access type by a duplicate
1758 -- declaration whose designated type is the nonlimited view.
1760 if Has_Non_Limited_View (Actual_DDT) then
1761 Anon := New_Copy (Actual_Typ);
1763 if Is_Itype (Anon) then
1764 Set_Scope (Anon, Current_Scope);
1765 end if;
1767 Set_Directly_Designated_Type
1768 (Anon, Non_Limited_View (Actual_DDT));
1769 Set_Etype (Actual_Dup, Anon);
1770 end if;
1771 end if;
1773 Conversion := Convert_To (Formal_Typ, Actual_Dup);
1774 Rewrite (Actual, Conversion);
1775 Analyze_And_Resolve (Actual, Formal_Typ);
1776 end if;
1777 end if;
1779 Next_Actual (Actual);
1780 Next_Formal (Formal);
1781 end loop;
1782 end Expand_Interface_Actuals;
1784 ----------------------------
1785 -- Expand_Interface_Thunk --
1786 ----------------------------
1788 procedure Expand_Interface_Thunk
1789 (Prim : Node_Id;
1790 Thunk_Id : out Entity_Id;
1791 Thunk_Code : out Node_Id)
1793 Loc : constant Source_Ptr := Sloc (Prim);
1794 Actuals : constant List_Id := New_List;
1795 Decl : constant List_Id := New_List;
1796 Formals : constant List_Id := New_List;
1797 Target : constant Entity_Id := Ultimate_Alias (Prim);
1799 Decl_1 : Node_Id;
1800 Decl_2 : Node_Id;
1801 Expr : Node_Id;
1802 Formal : Node_Id;
1803 Ftyp : Entity_Id;
1804 Iface_Formal : Node_Id := Empty; -- initialize to prevent warning
1805 New_Arg : Node_Id;
1806 Offset_To_Top : Node_Id;
1807 Target_Formal : Entity_Id;
1809 begin
1810 Thunk_Id := Empty;
1811 Thunk_Code := Empty;
1813 -- No thunk needed if the primitive has been eliminated
1815 if Is_Eliminated (Ultimate_Alias (Prim)) then
1816 return;
1818 -- In case of primitives that are functions without formals and a
1819 -- controlling result there is no need to build the thunk.
1821 elsif not Present (First_Formal (Target)) then
1822 pragma Assert (Ekind (Target) = E_Function
1823 and then Has_Controlling_Result (Target));
1824 return;
1825 end if;
1827 -- Duplicate the formals of the Target primitive. In the thunk, the type
1828 -- of the controlling formal is the covered interface type (instead of
1829 -- the target tagged type). Done to avoid problems with discriminated
1830 -- tagged types because, if the controlling type has discriminants with
1831 -- default values, then the type conversions done inside the body of
1832 -- the thunk (after the displacement of the pointer to the base of the
1833 -- actual object) generate code that modify its contents.
1835 -- Note: This special management is not done for predefined primitives
1836 -- because???
1838 if not Is_Predefined_Dispatching_Operation (Prim) then
1839 Iface_Formal := First_Formal (Interface_Alias (Prim));
1840 end if;
1842 Formal := First_Formal (Target);
1843 while Present (Formal) loop
1844 Ftyp := Etype (Formal);
1846 -- Use the interface type as the type of the controlling formal (see
1847 -- comment above).
1849 if not Is_Controlling_Formal (Formal)
1850 or else Is_Predefined_Dispatching_Operation (Prim)
1851 then
1852 Ftyp := Etype (Formal);
1853 Expr := New_Copy_Tree (Expression (Parent (Formal)));
1854 else
1855 Ftyp := Etype (Iface_Formal);
1856 Expr := Empty;
1857 end if;
1859 Append_To (Formals,
1860 Make_Parameter_Specification (Loc,
1861 Defining_Identifier =>
1862 Make_Defining_Identifier (Sloc (Formal),
1863 Chars => Chars (Formal)),
1864 In_Present => In_Present (Parent (Formal)),
1865 Out_Present => Out_Present (Parent (Formal)),
1866 Parameter_Type => New_Occurrence_Of (Ftyp, Loc),
1867 Expression => Expr));
1869 if not Is_Predefined_Dispatching_Operation (Prim) then
1870 Next_Formal (Iface_Formal);
1871 end if;
1873 Next_Formal (Formal);
1874 end loop;
1876 Target_Formal := First_Formal (Target);
1877 Formal := First (Formals);
1878 while Present (Formal) loop
1880 -- If the parent is a constrained discriminated type, then the
1881 -- primitive operation will have been defined on a first subtype.
1882 -- For proper matching with controlling type, use base type.
1884 if Ekind (Target_Formal) = E_In_Parameter
1885 and then Ekind (Etype (Target_Formal)) = E_Anonymous_Access_Type
1886 then
1887 Ftyp :=
1888 Base_Type (Directly_Designated_Type (Etype (Target_Formal)));
1889 else
1890 Ftyp := Base_Type (Etype (Target_Formal));
1891 end if;
1893 -- For concurrent types, the relevant information is found in the
1894 -- Corresponding_Record_Type, rather than the type entity itself.
1896 if Is_Concurrent_Type (Ftyp) then
1897 Ftyp := Corresponding_Record_Type (Ftyp);
1898 end if;
1900 if Ekind (Target_Formal) = E_In_Parameter
1901 and then Ekind (Etype (Target_Formal)) = E_Anonymous_Access_Type
1902 and then Is_Controlling_Formal (Target_Formal)
1903 then
1904 -- Generate:
1905 -- type T is access all <<type of the target formal>>
1906 -- S : Storage_Offset := Storage_Offset!(Formal)
1907 -- + Offset_To_Top (address!(Formal))
1909 Decl_2 :=
1910 Make_Full_Type_Declaration (Loc,
1911 Defining_Identifier => Make_Temporary (Loc, 'T'),
1912 Type_Definition =>
1913 Make_Access_To_Object_Definition (Loc,
1914 All_Present => True,
1915 Null_Exclusion_Present => False,
1916 Constant_Present => False,
1917 Subtype_Indication =>
1918 New_Occurrence_Of (Ftyp, Loc)));
1920 New_Arg :=
1921 Unchecked_Convert_To (RTE (RE_Address),
1922 New_Occurrence_Of (Defining_Identifier (Formal), Loc));
1924 if not RTE_Available (RE_Offset_To_Top) then
1925 Offset_To_Top :=
1926 Build_Offset_To_Top (Loc, New_Arg);
1927 else
1928 Offset_To_Top :=
1929 Make_Function_Call (Loc,
1930 Name => New_Occurrence_Of (RTE (RE_Offset_To_Top), Loc),
1931 Parameter_Associations => New_List (New_Arg));
1932 end if;
1934 Decl_1 :=
1935 Make_Object_Declaration (Loc,
1936 Defining_Identifier => Make_Temporary (Loc, 'S'),
1937 Constant_Present => True,
1938 Object_Definition =>
1939 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc),
1940 Expression =>
1941 Make_Op_Add (Loc,
1942 Left_Opnd =>
1943 Unchecked_Convert_To
1944 (RTE (RE_Storage_Offset),
1945 New_Occurrence_Of
1946 (Defining_Identifier (Formal), Loc)),
1947 Right_Opnd =>
1948 Offset_To_Top));
1950 Append_To (Decl, Decl_2);
1951 Append_To (Decl, Decl_1);
1953 -- Reference the new actual. Generate:
1954 -- T!(S)
1956 Append_To (Actuals,
1957 Unchecked_Convert_To
1958 (Defining_Identifier (Decl_2),
1959 New_Occurrence_Of (Defining_Identifier (Decl_1), Loc)));
1961 elsif Is_Controlling_Formal (Target_Formal) then
1963 -- Generate:
1964 -- S1 : Storage_Offset := Storage_Offset!(Formal'Address)
1965 -- + Offset_To_Top (Formal'Address)
1966 -- S2 : Addr_Ptr := Addr_Ptr!(S1)
1968 New_Arg :=
1969 Make_Attribute_Reference (Loc,
1970 Prefix =>
1971 New_Occurrence_Of (Defining_Identifier (Formal), Loc),
1972 Attribute_Name =>
1973 Name_Address);
1975 if not RTE_Available (RE_Offset_To_Top) then
1976 Offset_To_Top :=
1977 Build_Offset_To_Top (Loc, New_Arg);
1978 else
1979 Offset_To_Top :=
1980 Make_Function_Call (Loc,
1981 Name => New_Occurrence_Of (RTE (RE_Offset_To_Top), Loc),
1982 Parameter_Associations => New_List (New_Arg));
1983 end if;
1985 Decl_1 :=
1986 Make_Object_Declaration (Loc,
1987 Defining_Identifier => Make_Temporary (Loc, 'S'),
1988 Constant_Present => True,
1989 Object_Definition =>
1990 New_Occurrence_Of (RTE (RE_Storage_Offset), Loc),
1991 Expression =>
1992 Make_Op_Add (Loc,
1993 Left_Opnd =>
1994 Unchecked_Convert_To
1995 (RTE (RE_Storage_Offset),
1996 Make_Attribute_Reference (Loc,
1997 Prefix =>
1998 New_Occurrence_Of
1999 (Defining_Identifier (Formal), Loc),
2000 Attribute_Name => Name_Address)),
2001 Right_Opnd =>
2002 Offset_To_Top));
2004 Decl_2 :=
2005 Make_Object_Declaration (Loc,
2006 Defining_Identifier => Make_Temporary (Loc, 'S'),
2007 Constant_Present => True,
2008 Object_Definition =>
2009 New_Occurrence_Of (RTE (RE_Addr_Ptr), Loc),
2010 Expression =>
2011 Unchecked_Convert_To
2012 (RTE (RE_Addr_Ptr),
2013 New_Occurrence_Of (Defining_Identifier (Decl_1), Loc)));
2015 Append_To (Decl, Decl_1);
2016 Append_To (Decl, Decl_2);
2018 -- Reference the new actual, generate:
2019 -- Target_Formal (S2.all)
2021 Append_To (Actuals,
2022 Unchecked_Convert_To (Ftyp,
2023 Make_Explicit_Dereference (Loc,
2024 New_Occurrence_Of (Defining_Identifier (Decl_2), Loc))));
2026 -- Ensure proper matching of access types. Required to avoid
2027 -- reporting spurious errors.
2029 elsif Is_Access_Type (Etype (Target_Formal)) then
2030 Append_To (Actuals,
2031 Unchecked_Convert_To (Base_Type (Etype (Target_Formal)),
2032 New_Occurrence_Of (Defining_Identifier (Formal), Loc)));
2034 -- No special management required for this actual
2036 else
2037 Append_To (Actuals,
2038 New_Occurrence_Of (Defining_Identifier (Formal), Loc));
2039 end if;
2041 Next_Formal (Target_Formal);
2042 Next (Formal);
2043 end loop;
2045 Thunk_Id := Make_Temporary (Loc, 'T');
2046 Set_Ekind (Thunk_Id, Ekind (Prim));
2047 Set_Is_Thunk (Thunk_Id);
2048 Set_Convention (Thunk_Id, Convention (Prim));
2049 Set_Thunk_Entity (Thunk_Id, Target);
2051 -- Procedure case
2053 if Ekind (Target) = E_Procedure then
2054 Thunk_Code :=
2055 Make_Subprogram_Body (Loc,
2056 Specification =>
2057 Make_Procedure_Specification (Loc,
2058 Defining_Unit_Name => Thunk_Id,
2059 Parameter_Specifications => Formals),
2060 Declarations => Decl,
2061 Handled_Statement_Sequence =>
2062 Make_Handled_Sequence_Of_Statements (Loc,
2063 Statements => New_List (
2064 Make_Procedure_Call_Statement (Loc,
2065 Name => New_Occurrence_Of (Target, Loc),
2066 Parameter_Associations => Actuals))));
2068 -- Function case
2070 else pragma Assert (Ekind (Target) = E_Function);
2071 declare
2072 Result_Def : Node_Id;
2073 Call_Node : Node_Id;
2075 begin
2076 Call_Node :=
2077 Make_Function_Call (Loc,
2078 Name => New_Occurrence_Of (Target, Loc),
2079 Parameter_Associations => Actuals);
2081 if not Is_Interface (Etype (Prim)) then
2082 Result_Def := New_Copy (Result_Definition (Parent (Target)));
2084 -- Thunk of function returning a class-wide interface object. No
2085 -- extra displacement needed since the displacement is generated
2086 -- in the return statement of Prim. Example:
2088 -- type Iface is interface ...
2089 -- function F (O : Iface) return Iface'Class;
2091 -- type T is new ... and Iface with ...
2092 -- function F (O : T) return Iface'Class;
2094 elsif Is_Class_Wide_Type (Etype (Prim)) then
2095 Result_Def := New_Occurrence_Of (Etype (Prim), Loc);
2097 -- Thunk of function returning an interface object. Displacement
2098 -- needed. Example:
2100 -- type Iface is interface ...
2101 -- function F (O : Iface) return Iface;
2103 -- type T is new ... and Iface with ...
2104 -- function F (O : T) return T;
2106 else
2107 Result_Def :=
2108 New_Occurrence_Of (Class_Wide_Type (Etype (Prim)), Loc);
2110 -- Adding implicit conversion to force the displacement of
2111 -- the pointer to the object to reference the corresponding
2112 -- secondary dispatch table.
2114 Call_Node :=
2115 Make_Type_Conversion (Loc,
2116 Subtype_Mark =>
2117 New_Occurrence_Of (Class_Wide_Type (Etype (Prim)), Loc),
2118 Expression => Relocate_Node (Call_Node));
2119 end if;
2121 Thunk_Code :=
2122 Make_Subprogram_Body (Loc,
2123 Specification =>
2124 Make_Function_Specification (Loc,
2125 Defining_Unit_Name => Thunk_Id,
2126 Parameter_Specifications => Formals,
2127 Result_Definition => Result_Def),
2128 Declarations => Decl,
2129 Handled_Statement_Sequence =>
2130 Make_Handled_Sequence_Of_Statements (Loc,
2131 Statements => New_List (
2132 Make_Simple_Return_Statement (Loc, Call_Node))));
2133 end;
2134 end if;
2135 end Expand_Interface_Thunk;
2137 --------------------------
2138 -- Has_CPP_Constructors --
2139 --------------------------
2141 function Has_CPP_Constructors (Typ : Entity_Id) return Boolean is
2142 E : Entity_Id;
2144 begin
2145 -- Look for the constructor entities
2147 E := Next_Entity (Typ);
2148 while Present (E) loop
2149 if Ekind (E) = E_Function and then Is_Constructor (E) then
2150 return True;
2151 end if;
2153 Next_Entity (E);
2154 end loop;
2156 return False;
2157 end Has_CPP_Constructors;
2159 ------------
2160 -- Has_DT --
2161 ------------
2163 function Has_DT (Typ : Entity_Id) return Boolean is
2164 begin
2165 return not Is_Interface (Typ)
2166 and then not Restriction_Active (No_Dispatching_Calls);
2167 end Has_DT;
2169 ----------------------------------
2170 -- Is_Expanded_Dispatching_Call --
2171 ----------------------------------
2173 function Is_Expanded_Dispatching_Call (N : Node_Id) return Boolean is
2174 begin
2175 return Nkind (N) in N_Subprogram_Call
2176 and then Nkind (Name (N)) = N_Explicit_Dereference
2177 and then Is_Dispatch_Table_Entity (Etype (Name (N)));
2178 end Is_Expanded_Dispatching_Call;
2180 -------------------------------------
2181 -- Is_Predefined_Dispatching_Alias --
2182 -------------------------------------
2184 function Is_Predefined_Dispatching_Alias (Prim : Entity_Id) return Boolean
2186 begin
2187 return not Is_Predefined_Dispatching_Operation (Prim)
2188 and then Present (Alias (Prim))
2189 and then Is_Predefined_Dispatching_Operation (Ultimate_Alias (Prim));
2190 end Is_Predefined_Dispatching_Alias;
2192 ----------------------------------------
2193 -- Make_Disp_Asynchronous_Select_Body --
2194 ----------------------------------------
2196 -- For interface types, generate:
2198 -- procedure _Disp_Asynchronous_Select
2199 -- (T : in out <Typ>;
2200 -- S : Integer;
2201 -- P : System.Address;
2202 -- B : out System.Storage_Elements.Dummy_Communication_Block;
2203 -- F : out Boolean)
2204 -- is
2205 -- begin
2206 -- F := False;
2207 -- C := Ada.Tags.POK_Function;
2208 -- end _Disp_Asynchronous_Select;
2210 -- For protected types, generate:
2212 -- procedure _Disp_Asynchronous_Select
2213 -- (T : in out <Typ>;
2214 -- S : Integer;
2215 -- P : System.Address;
2216 -- B : out System.Storage_Elements.Dummy_Communication_Block;
2217 -- F : out Boolean)
2218 -- is
2219 -- I : Integer :=
2220 -- Ada.Tags.Get_Entry_Index (Ada.Tags.Tag (<Typ>VP, S));
2221 -- Bnn : System.Tasking.Protected_Objects.Operations.
2222 -- Communication_Block;
2223 -- begin
2224 -- System.Tasking.Protected_Objects.Operations.Protected_Entry_Call
2225 -- (T._object'Access,
2226 -- System.Tasking.Protected_Objects.Protected_Entry_Index (I),
2227 -- P,
2228 -- System.Tasking.Asynchronous_Call,
2229 -- Bnn);
2230 -- B := System.Storage_Elements.Dummy_Communication_Block (Bnn);
2231 -- end _Disp_Asynchronous_Select;
2233 -- For task types, generate:
2235 -- procedure _Disp_Asynchronous_Select
2236 -- (T : in out <Typ>;
2237 -- S : Integer;
2238 -- P : System.Address;
2239 -- B : out System.Storage_Elements.Dummy_Communication_Block;
2240 -- F : out Boolean)
2241 -- is
2242 -- I : Integer :=
2243 -- Ada.Tags.Get_Entry_Index (Ada.Tags.Tag (<Typ>VP, S));
2244 -- begin
2245 -- System.Tasking.Rendezvous.Task_Entry_Call
2246 -- (T._task_id,
2247 -- System.Tasking.Task_Entry_Index (I),
2248 -- P,
2249 -- System.Tasking.Asynchronous_Call,
2250 -- F);
2251 -- end _Disp_Asynchronous_Select;
2253 function Make_Disp_Asynchronous_Select_Body
2254 (Typ : Entity_Id) return Node_Id
2256 Com_Block : Entity_Id;
2257 Conc_Typ : Entity_Id := Empty;
2258 Decls : constant List_Id := New_List;
2259 Loc : constant Source_Ptr := Sloc (Typ);
2260 Obj_Ref : Node_Id;
2261 Stmts : constant List_Id := New_List;
2262 Tag_Node : Node_Id;
2264 begin
2265 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
2267 -- Null body is generated for interface types
2269 if Is_Interface (Typ) then
2270 return
2271 Make_Subprogram_Body (Loc,
2272 Specification =>
2273 Make_Disp_Asynchronous_Select_Spec (Typ),
2274 Declarations => New_List,
2275 Handled_Statement_Sequence =>
2276 Make_Handled_Sequence_Of_Statements (Loc,
2277 New_List (
2278 Make_Assignment_Statement (Loc,
2279 Name => Make_Identifier (Loc, Name_uF),
2280 Expression => New_Occurrence_Of (Standard_False, Loc)))));
2281 end if;
2283 if Is_Concurrent_Record_Type (Typ) then
2284 Conc_Typ := Corresponding_Concurrent_Type (Typ);
2286 -- Generate:
2287 -- I : Integer :=
2288 -- Ada.Tags.Get_Entry_Index (Ada.Tags.Tag! (<type>VP), S);
2290 -- where I will be used to capture the entry index of the primitive
2291 -- wrapper at position S.
2293 if Tagged_Type_Expansion then
2294 Tag_Node :=
2295 Unchecked_Convert_To (RTE (RE_Tag),
2296 New_Occurrence_Of
2297 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc));
2298 else
2299 Tag_Node :=
2300 Make_Attribute_Reference (Loc,
2301 Prefix => New_Occurrence_Of (Typ, Loc),
2302 Attribute_Name => Name_Tag);
2303 end if;
2305 Append_To (Decls,
2306 Make_Object_Declaration (Loc,
2307 Defining_Identifier =>
2308 Make_Defining_Identifier (Loc, Name_uI),
2309 Object_Definition =>
2310 New_Occurrence_Of (Standard_Integer, Loc),
2311 Expression =>
2312 Make_Function_Call (Loc,
2313 Name =>
2314 New_Occurrence_Of (RTE (RE_Get_Entry_Index), Loc),
2315 Parameter_Associations =>
2316 New_List (Tag_Node, Make_Identifier (Loc, Name_uS)))));
2318 if Ekind (Conc_Typ) = E_Protected_Type then
2320 -- Generate:
2321 -- Bnn : Communication_Block;
2323 Com_Block := Make_Temporary (Loc, 'B');
2324 Append_To (Decls,
2325 Make_Object_Declaration (Loc,
2326 Defining_Identifier => Com_Block,
2327 Object_Definition =>
2328 New_Occurrence_Of (RTE (RE_Communication_Block), Loc)));
2330 -- Build T._object'Access for calls below
2332 Obj_Ref :=
2333 Make_Attribute_Reference (Loc,
2334 Attribute_Name => Name_Unchecked_Access,
2335 Prefix =>
2336 Make_Selected_Component (Loc,
2337 Prefix => Make_Identifier (Loc, Name_uT),
2338 Selector_Name => Make_Identifier (Loc, Name_uObject)));
2340 case Corresponding_Runtime_Package (Conc_Typ) is
2341 when System_Tasking_Protected_Objects_Entries =>
2343 -- Generate:
2344 -- Protected_Entry_Call
2345 -- (T._object'Access, -- Object
2346 -- Protected_Entry_Index! (I), -- E
2347 -- P, -- Uninterpreted_Data
2348 -- Asynchronous_Call, -- Mode
2349 -- Bnn); -- Communication_Block
2351 -- where T is the protected object, I is the entry index, P
2352 -- is the wrapped parameters and B is the name of the
2353 -- communication block.
2355 Append_To (Stmts,
2356 Make_Procedure_Call_Statement (Loc,
2357 Name =>
2358 New_Occurrence_Of (RTE (RE_Protected_Entry_Call), Loc),
2359 Parameter_Associations =>
2360 New_List (
2361 Obj_Ref,
2363 Make_Unchecked_Type_Conversion (Loc, -- entry index
2364 Subtype_Mark =>
2365 New_Occurrence_Of
2366 (RTE (RE_Protected_Entry_Index), Loc),
2367 Expression => Make_Identifier (Loc, Name_uI)),
2369 Make_Identifier (Loc, Name_uP), -- parameter block
2370 New_Occurrence_Of -- Asynchronous_Call
2371 (RTE (RE_Asynchronous_Call), Loc),
2372 New_Occurrence_Of -- comm block
2373 (Com_Block, Loc))));
2375 when others =>
2376 raise Program_Error;
2377 end case;
2379 -- Generate:
2380 -- B := Dummy_Communication_Block (Bnn);
2382 Append_To (Stmts,
2383 Make_Assignment_Statement (Loc,
2384 Name => Make_Identifier (Loc, Name_uB),
2385 Expression =>
2386 Make_Unchecked_Type_Conversion (Loc,
2387 Subtype_Mark =>
2388 New_Occurrence_Of
2389 (RTE (RE_Dummy_Communication_Block), Loc),
2390 Expression => New_Occurrence_Of (Com_Block, Loc))));
2392 -- Generate:
2393 -- F := False;
2395 Append_To (Stmts,
2396 Make_Assignment_Statement (Loc,
2397 Name => Make_Identifier (Loc, Name_uF),
2398 Expression => New_Occurrence_Of (Standard_False, Loc)));
2400 else
2401 pragma Assert (Ekind (Conc_Typ) = E_Task_Type);
2403 -- Generate:
2404 -- Task_Entry_Call
2405 -- (T._task_id, -- Acceptor
2406 -- Task_Entry_Index! (I), -- E
2407 -- P, -- Uninterpreted_Data
2408 -- Asynchronous_Call, -- Mode
2409 -- F); -- Rendezvous_Successful
2411 -- where T is the task object, I is the entry index, P is the
2412 -- wrapped parameters and F is the status flag.
2414 Append_To (Stmts,
2415 Make_Procedure_Call_Statement (Loc,
2416 Name =>
2417 New_Occurrence_Of (RTE (RE_Task_Entry_Call), Loc),
2418 Parameter_Associations =>
2419 New_List (
2420 Make_Selected_Component (Loc, -- T._task_id
2421 Prefix => Make_Identifier (Loc, Name_uT),
2422 Selector_Name => Make_Identifier (Loc, Name_uTask_Id)),
2424 Make_Unchecked_Type_Conversion (Loc, -- entry index
2425 Subtype_Mark =>
2426 New_Occurrence_Of (RTE (RE_Task_Entry_Index), Loc),
2427 Expression => Make_Identifier (Loc, Name_uI)),
2429 Make_Identifier (Loc, Name_uP), -- parameter block
2430 New_Occurrence_Of -- Asynchronous_Call
2431 (RTE (RE_Asynchronous_Call), Loc),
2432 Make_Identifier (Loc, Name_uF)))); -- status flag
2433 end if;
2435 else
2436 -- Ensure that the statements list is non-empty
2438 Append_To (Stmts,
2439 Make_Assignment_Statement (Loc,
2440 Name => Make_Identifier (Loc, Name_uF),
2441 Expression => New_Occurrence_Of (Standard_False, Loc)));
2442 end if;
2444 return
2445 Make_Subprogram_Body (Loc,
2446 Specification =>
2447 Make_Disp_Asynchronous_Select_Spec (Typ),
2448 Declarations => Decls,
2449 Handled_Statement_Sequence =>
2450 Make_Handled_Sequence_Of_Statements (Loc, Stmts));
2451 end Make_Disp_Asynchronous_Select_Body;
2453 ----------------------------------------
2454 -- Make_Disp_Asynchronous_Select_Spec --
2455 ----------------------------------------
2457 function Make_Disp_Asynchronous_Select_Spec
2458 (Typ : Entity_Id) return Node_Id
2460 Loc : constant Source_Ptr := Sloc (Typ);
2461 Def_Id : constant Node_Id :=
2462 Make_Defining_Identifier (Loc,
2463 Name_uDisp_Asynchronous_Select);
2464 Params : constant List_Id := New_List;
2466 begin
2467 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
2469 -- T : in out Typ; -- Object parameter
2470 -- S : Integer; -- Primitive operation slot
2471 -- P : Address; -- Wrapped parameters
2472 -- B : out Dummy_Communication_Block; -- Communication block dummy
2473 -- F : out Boolean; -- Status flag
2475 Append_List_To (Params, New_List (
2477 Make_Parameter_Specification (Loc,
2478 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uT),
2479 Parameter_Type => New_Occurrence_Of (Typ, Loc),
2480 In_Present => True,
2481 Out_Present => True),
2483 Make_Parameter_Specification (Loc,
2484 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uS),
2485 Parameter_Type => New_Occurrence_Of (Standard_Integer, Loc)),
2487 Make_Parameter_Specification (Loc,
2488 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uP),
2489 Parameter_Type => New_Occurrence_Of (RTE (RE_Address), Loc)),
2491 Make_Parameter_Specification (Loc,
2492 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uB),
2493 Parameter_Type =>
2494 New_Occurrence_Of (RTE (RE_Dummy_Communication_Block), Loc),
2495 Out_Present => True),
2497 Make_Parameter_Specification (Loc,
2498 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uF),
2499 Parameter_Type => New_Occurrence_Of (Standard_Boolean, Loc),
2500 Out_Present => True)));
2502 return
2503 Make_Procedure_Specification (Loc,
2504 Defining_Unit_Name => Def_Id,
2505 Parameter_Specifications => Params);
2506 end Make_Disp_Asynchronous_Select_Spec;
2508 ---------------------------------------
2509 -- Make_Disp_Conditional_Select_Body --
2510 ---------------------------------------
2512 -- For interface types, generate:
2514 -- procedure _Disp_Conditional_Select
2515 -- (T : in out <Typ>;
2516 -- S : Integer;
2517 -- P : System.Address;
2518 -- C : out Ada.Tags.Prim_Op_Kind;
2519 -- F : out Boolean)
2520 -- is
2521 -- begin
2522 -- F := False;
2523 -- C := Ada.Tags.POK_Function;
2524 -- end _Disp_Conditional_Select;
2526 -- For protected types, generate:
2528 -- procedure _Disp_Conditional_Select
2529 -- (T : in out <Typ>;
2530 -- S : Integer;
2531 -- P : System.Address;
2532 -- C : out Ada.Tags.Prim_Op_Kind;
2533 -- F : out Boolean)
2534 -- is
2535 -- I : Integer;
2536 -- Bnn : System.Tasking.Protected_Objects.Operations.
2537 -- Communication_Block;
2539 -- begin
2540 -- C := Ada.Tags.Get_Prim_Op_Kind (Ada.Tags.Tag (<Typ>VP, S));
2542 -- if C = Ada.Tags.POK_Procedure
2543 -- or else C = Ada.Tags.POK_Protected_Procedure
2544 -- or else C = Ada.Tags.POK_Task_Procedure
2545 -- then
2546 -- F := True;
2547 -- return;
2548 -- end if;
2550 -- I := Ada.Tags.Get_Entry_Index (Ada.Tags.Tag (<Typ>VP, S));
2551 -- System.Tasking.Protected_Objects.Operations.Protected_Entry_Call
2552 -- (T.object'Access,
2553 -- System.Tasking.Protected_Objects.Protected_Entry_Index (I),
2554 -- P,
2555 -- System.Tasking.Conditional_Call,
2556 -- Bnn);
2557 -- F := not Cancelled (Bnn);
2558 -- end _Disp_Conditional_Select;
2560 -- For task types, generate:
2562 -- procedure _Disp_Conditional_Select
2563 -- (T : in out <Typ>;
2564 -- S : Integer;
2565 -- P : System.Address;
2566 -- C : out Ada.Tags.Prim_Op_Kind;
2567 -- F : out Boolean)
2568 -- is
2569 -- I : Integer;
2571 -- begin
2572 -- I := Ada.Tags.Get_Entry_Index (Ada.Tags.Tag (<Typ>VP, S));
2573 -- System.Tasking.Rendezvous.Task_Entry_Call
2574 -- (T._task_id,
2575 -- System.Tasking.Task_Entry_Index (I),
2576 -- P,
2577 -- System.Tasking.Conditional_Call,
2578 -- F);
2579 -- end _Disp_Conditional_Select;
2581 function Make_Disp_Conditional_Select_Body
2582 (Typ : Entity_Id) return Node_Id
2584 Loc : constant Source_Ptr := Sloc (Typ);
2585 Blk_Nam : Entity_Id;
2586 Conc_Typ : Entity_Id := Empty;
2587 Decls : constant List_Id := New_List;
2588 Obj_Ref : Node_Id;
2589 Stmts : constant List_Id := New_List;
2590 Tag_Node : Node_Id;
2592 begin
2593 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
2595 -- Null body is generated for interface types
2597 if Is_Interface (Typ) then
2598 return
2599 Make_Subprogram_Body (Loc,
2600 Specification =>
2601 Make_Disp_Conditional_Select_Spec (Typ),
2602 Declarations => No_List,
2603 Handled_Statement_Sequence =>
2604 Make_Handled_Sequence_Of_Statements (Loc,
2605 New_List (Make_Assignment_Statement (Loc,
2606 Name => Make_Identifier (Loc, Name_uF),
2607 Expression => New_Occurrence_Of (Standard_False, Loc)))));
2608 end if;
2610 if Is_Concurrent_Record_Type (Typ) then
2611 Conc_Typ := Corresponding_Concurrent_Type (Typ);
2613 -- Generate:
2614 -- I : Integer;
2616 -- where I will be used to capture the entry index of the primitive
2617 -- wrapper at position S.
2619 Append_To (Decls,
2620 Make_Object_Declaration (Loc,
2621 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uI),
2622 Object_Definition =>
2623 New_Occurrence_Of (Standard_Integer, Loc)));
2625 -- Generate:
2626 -- C := Ada.Tags.Get_Prim_Op_Kind (Ada.Tags.Tag! (<type>VP), S);
2628 -- if C = POK_Procedure
2629 -- or else C = POK_Protected_Procedure
2630 -- or else C = POK_Task_Procedure;
2631 -- then
2632 -- F := True;
2633 -- return;
2634 -- end if;
2636 Build_Common_Dispatching_Select_Statements (Typ, Stmts);
2638 -- Generate:
2639 -- Bnn : Communication_Block;
2641 -- where Bnn is the name of the communication block used in the
2642 -- call to Protected_Entry_Call.
2644 Blk_Nam := Make_Temporary (Loc, 'B');
2645 Append_To (Decls,
2646 Make_Object_Declaration (Loc,
2647 Defining_Identifier => Blk_Nam,
2648 Object_Definition =>
2649 New_Occurrence_Of (RTE (RE_Communication_Block), Loc)));
2651 -- Generate:
2652 -- I := Ada.Tags.Get_Entry_Index (Ada.Tags.Tag! (<type>VP), S);
2654 -- I is the entry index and S is the dispatch table slot
2656 if Tagged_Type_Expansion then
2657 Tag_Node :=
2658 Unchecked_Convert_To (RTE (RE_Tag),
2659 New_Occurrence_Of
2660 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc));
2662 else
2663 Tag_Node :=
2664 Make_Attribute_Reference (Loc,
2665 Prefix => New_Occurrence_Of (Typ, Loc),
2666 Attribute_Name => Name_Tag);
2667 end if;
2669 Append_To (Stmts,
2670 Make_Assignment_Statement (Loc,
2671 Name => Make_Identifier (Loc, Name_uI),
2672 Expression =>
2673 Make_Function_Call (Loc,
2674 Name =>
2675 New_Occurrence_Of (RTE (RE_Get_Entry_Index), Loc),
2676 Parameter_Associations => New_List (
2677 Tag_Node,
2678 Make_Identifier (Loc, Name_uS)))));
2680 if Ekind (Conc_Typ) = E_Protected_Type then
2682 Obj_Ref := -- T._object'Access
2683 Make_Attribute_Reference (Loc,
2684 Attribute_Name => Name_Unchecked_Access,
2685 Prefix =>
2686 Make_Selected_Component (Loc,
2687 Prefix => Make_Identifier (Loc, Name_uT),
2688 Selector_Name => Make_Identifier (Loc, Name_uObject)));
2690 case Corresponding_Runtime_Package (Conc_Typ) is
2691 when System_Tasking_Protected_Objects_Entries =>
2692 -- Generate:
2694 -- Protected_Entry_Call
2695 -- (T._object'Access, -- Object
2696 -- Protected_Entry_Index! (I), -- E
2697 -- P, -- Uninterpreted_Data
2698 -- Conditional_Call, -- Mode
2699 -- Bnn); -- Block
2701 -- where T is the protected object, I is the entry index, P
2702 -- are the wrapped parameters and Bnn is the name of the
2703 -- communication block.
2705 Append_To (Stmts,
2706 Make_Procedure_Call_Statement (Loc,
2707 Name =>
2708 New_Occurrence_Of (RTE (RE_Protected_Entry_Call), Loc),
2709 Parameter_Associations => New_List (
2710 Obj_Ref,
2712 Make_Unchecked_Type_Conversion (Loc, -- entry index
2713 Subtype_Mark =>
2714 New_Occurrence_Of
2715 (RTE (RE_Protected_Entry_Index), Loc),
2716 Expression => Make_Identifier (Loc, Name_uI)),
2718 Make_Identifier (Loc, Name_uP), -- parameter block
2720 New_Occurrence_Of -- Conditional_Call
2721 (RTE (RE_Conditional_Call), Loc),
2722 New_Occurrence_Of -- Bnn
2723 (Blk_Nam, Loc))));
2725 when System_Tasking_Protected_Objects_Single_Entry =>
2727 -- If we are compiling for a restricted run-time, the call
2728 -- uses the simpler form.
2730 Append_To (Stmts,
2731 Make_Procedure_Call_Statement (Loc,
2732 Name =>
2733 New_Occurrence_Of
2734 (RTE (RE_Protected_Single_Entry_Call), Loc),
2735 Parameter_Associations => New_List (
2736 Obj_Ref,
2738 Make_Attribute_Reference (Loc,
2739 Prefix => Make_Identifier (Loc, Name_uP),
2740 Attribute_Name => Name_Address),
2742 New_Occurrence_Of
2743 (RTE (RE_Conditional_Call), Loc))));
2744 when others =>
2745 raise Program_Error;
2746 end case;
2748 -- Generate:
2749 -- F := not Cancelled (Bnn);
2751 -- where F is the success flag. The status of Cancelled is negated
2752 -- in order to match the behavior of the version for task types.
2754 Append_To (Stmts,
2755 Make_Assignment_Statement (Loc,
2756 Name => Make_Identifier (Loc, Name_uF),
2757 Expression =>
2758 Make_Op_Not (Loc,
2759 Right_Opnd =>
2760 Make_Function_Call (Loc,
2761 Name =>
2762 New_Occurrence_Of (RTE (RE_Cancelled), Loc),
2763 Parameter_Associations => New_List (
2764 New_Occurrence_Of (Blk_Nam, Loc))))));
2765 else
2766 pragma Assert (Ekind (Conc_Typ) = E_Task_Type);
2768 -- Generate:
2769 -- Task_Entry_Call
2770 -- (T._task_id, -- Acceptor
2771 -- Task_Entry_Index! (I), -- E
2772 -- P, -- Uninterpreted_Data
2773 -- Conditional_Call, -- Mode
2774 -- F); -- Rendezvous_Successful
2776 -- where T is the task object, I is the entry index, P are the
2777 -- wrapped parameters and F is the status flag.
2779 Append_To (Stmts,
2780 Make_Procedure_Call_Statement (Loc,
2781 Name =>
2782 New_Occurrence_Of (RTE (RE_Task_Entry_Call), Loc),
2783 Parameter_Associations => New_List (
2785 Make_Selected_Component (Loc, -- T._task_id
2786 Prefix => Make_Identifier (Loc, Name_uT),
2787 Selector_Name => Make_Identifier (Loc, Name_uTask_Id)),
2789 Make_Unchecked_Type_Conversion (Loc, -- entry index
2790 Subtype_Mark =>
2791 New_Occurrence_Of (RTE (RE_Task_Entry_Index), Loc),
2792 Expression => Make_Identifier (Loc, Name_uI)),
2794 Make_Identifier (Loc, Name_uP), -- parameter block
2795 New_Occurrence_Of -- Conditional_Call
2796 (RTE (RE_Conditional_Call), Loc),
2797 Make_Identifier (Loc, Name_uF)))); -- status flag
2798 end if;
2800 else
2801 -- Initialize out parameters
2803 Append_To (Stmts,
2804 Make_Assignment_Statement (Loc,
2805 Name => Make_Identifier (Loc, Name_uF),
2806 Expression => New_Occurrence_Of (Standard_False, Loc)));
2807 Append_To (Stmts,
2808 Make_Assignment_Statement (Loc,
2809 Name => Make_Identifier (Loc, Name_uC),
2810 Expression => New_Occurrence_Of (RTE (RE_POK_Function), Loc)));
2811 end if;
2813 return
2814 Make_Subprogram_Body (Loc,
2815 Specification =>
2816 Make_Disp_Conditional_Select_Spec (Typ),
2817 Declarations => Decls,
2818 Handled_Statement_Sequence =>
2819 Make_Handled_Sequence_Of_Statements (Loc, Stmts));
2820 end Make_Disp_Conditional_Select_Body;
2822 ---------------------------------------
2823 -- Make_Disp_Conditional_Select_Spec --
2824 ---------------------------------------
2826 function Make_Disp_Conditional_Select_Spec
2827 (Typ : Entity_Id) return Node_Id
2829 Loc : constant Source_Ptr := Sloc (Typ);
2830 Def_Id : constant Node_Id :=
2831 Make_Defining_Identifier (Loc,
2832 Name_uDisp_Conditional_Select);
2833 Params : constant List_Id := New_List;
2835 begin
2836 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
2838 -- T : in out Typ; -- Object parameter
2839 -- S : Integer; -- Primitive operation slot
2840 -- P : Address; -- Wrapped parameters
2841 -- C : out Prim_Op_Kind; -- Call kind
2842 -- F : out Boolean; -- Status flag
2844 Append_List_To (Params, New_List (
2846 Make_Parameter_Specification (Loc,
2847 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uT),
2848 Parameter_Type => New_Occurrence_Of (Typ, Loc),
2849 In_Present => True,
2850 Out_Present => True),
2852 Make_Parameter_Specification (Loc,
2853 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uS),
2854 Parameter_Type => New_Occurrence_Of (Standard_Integer, Loc)),
2856 Make_Parameter_Specification (Loc,
2857 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uP),
2858 Parameter_Type => New_Occurrence_Of (RTE (RE_Address), Loc)),
2860 Make_Parameter_Specification (Loc,
2861 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uC),
2862 Parameter_Type =>
2863 New_Occurrence_Of (RTE (RE_Prim_Op_Kind), Loc),
2864 Out_Present => True),
2866 Make_Parameter_Specification (Loc,
2867 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uF),
2868 Parameter_Type => New_Occurrence_Of (Standard_Boolean, Loc),
2869 Out_Present => True)));
2871 return
2872 Make_Procedure_Specification (Loc,
2873 Defining_Unit_Name => Def_Id,
2874 Parameter_Specifications => Params);
2875 end Make_Disp_Conditional_Select_Spec;
2877 -------------------------------------
2878 -- Make_Disp_Get_Prim_Op_Kind_Body --
2879 -------------------------------------
2881 function Make_Disp_Get_Prim_Op_Kind_Body (Typ : Entity_Id) return Node_Id is
2882 Loc : constant Source_Ptr := Sloc (Typ);
2883 Tag_Node : Node_Id;
2885 begin
2886 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
2888 if Is_Interface (Typ) then
2889 return
2890 Make_Subprogram_Body (Loc,
2891 Specification =>
2892 Make_Disp_Get_Prim_Op_Kind_Spec (Typ),
2893 Declarations => New_List,
2894 Handled_Statement_Sequence =>
2895 Make_Handled_Sequence_Of_Statements (Loc,
2896 New_List (Make_Null_Statement (Loc))));
2897 end if;
2899 -- Generate:
2900 -- C := get_prim_op_kind (tag! (<type>VP), S);
2902 -- where C is the out parameter capturing the call kind and S is the
2903 -- dispatch table slot number.
2905 if Tagged_Type_Expansion then
2906 Tag_Node :=
2907 Unchecked_Convert_To (RTE (RE_Tag),
2908 New_Occurrence_Of
2909 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc));
2911 else
2912 Tag_Node :=
2913 Make_Attribute_Reference (Loc,
2914 Prefix => New_Occurrence_Of (Typ, Loc),
2915 Attribute_Name => Name_Tag);
2916 end if;
2918 return
2919 Make_Subprogram_Body (Loc,
2920 Specification =>
2921 Make_Disp_Get_Prim_Op_Kind_Spec (Typ),
2922 Declarations => New_List,
2923 Handled_Statement_Sequence =>
2924 Make_Handled_Sequence_Of_Statements (Loc,
2925 New_List (
2926 Make_Assignment_Statement (Loc,
2927 Name => Make_Identifier (Loc, Name_uC),
2928 Expression =>
2929 Make_Function_Call (Loc,
2930 Name =>
2931 New_Occurrence_Of (RTE (RE_Get_Prim_Op_Kind), Loc),
2932 Parameter_Associations => New_List (
2933 Tag_Node,
2934 Make_Identifier (Loc, Name_uS)))))));
2935 end Make_Disp_Get_Prim_Op_Kind_Body;
2937 -------------------------------------
2938 -- Make_Disp_Get_Prim_Op_Kind_Spec --
2939 -------------------------------------
2941 function Make_Disp_Get_Prim_Op_Kind_Spec
2942 (Typ : Entity_Id) return Node_Id
2944 Loc : constant Source_Ptr := Sloc (Typ);
2945 Def_Id : constant Node_Id :=
2946 Make_Defining_Identifier (Loc, Name_uDisp_Get_Prim_Op_Kind);
2947 Params : constant List_Id := New_List;
2949 begin
2950 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
2952 -- T : in out Typ; -- Object parameter
2953 -- S : Integer; -- Primitive operation slot
2954 -- C : out Prim_Op_Kind; -- Call kind
2956 Append_List_To (Params, New_List (
2958 Make_Parameter_Specification (Loc,
2959 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uT),
2960 Parameter_Type => New_Occurrence_Of (Typ, Loc),
2961 In_Present => True,
2962 Out_Present => True),
2964 Make_Parameter_Specification (Loc,
2965 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uS),
2966 Parameter_Type => New_Occurrence_Of (Standard_Integer, Loc)),
2968 Make_Parameter_Specification (Loc,
2969 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uC),
2970 Parameter_Type =>
2971 New_Occurrence_Of (RTE (RE_Prim_Op_Kind), Loc),
2972 Out_Present => True)));
2974 return
2975 Make_Procedure_Specification (Loc,
2976 Defining_Unit_Name => Def_Id,
2977 Parameter_Specifications => Params);
2978 end Make_Disp_Get_Prim_Op_Kind_Spec;
2980 --------------------------------
2981 -- Make_Disp_Get_Task_Id_Body --
2982 --------------------------------
2984 function Make_Disp_Get_Task_Id_Body
2985 (Typ : Entity_Id) return Node_Id
2987 Loc : constant Source_Ptr := Sloc (Typ);
2988 Ret : Node_Id;
2990 begin
2991 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
2993 if Is_Concurrent_Record_Type (Typ)
2994 and then Ekind (Corresponding_Concurrent_Type (Typ)) = E_Task_Type
2995 then
2996 -- Generate:
2997 -- return To_Address (_T._task_id);
2999 Ret :=
3000 Make_Simple_Return_Statement (Loc,
3001 Expression =>
3002 Make_Unchecked_Type_Conversion (Loc,
3003 Subtype_Mark => New_Occurrence_Of (RTE (RE_Address), Loc),
3004 Expression =>
3005 Make_Selected_Component (Loc,
3006 Prefix => Make_Identifier (Loc, Name_uT),
3007 Selector_Name => Make_Identifier (Loc, Name_uTask_Id))));
3009 -- A null body is constructed for non-task types
3011 else
3012 -- Generate:
3013 -- return Null_Address;
3015 Ret :=
3016 Make_Simple_Return_Statement (Loc,
3017 Expression => New_Occurrence_Of (RTE (RE_Null_Address), Loc));
3018 end if;
3020 return
3021 Make_Subprogram_Body (Loc,
3022 Specification => Make_Disp_Get_Task_Id_Spec (Typ),
3023 Declarations => New_List,
3024 Handled_Statement_Sequence =>
3025 Make_Handled_Sequence_Of_Statements (Loc, New_List (Ret)));
3026 end Make_Disp_Get_Task_Id_Body;
3028 --------------------------------
3029 -- Make_Disp_Get_Task_Id_Spec --
3030 --------------------------------
3032 function Make_Disp_Get_Task_Id_Spec
3033 (Typ : Entity_Id) return Node_Id
3035 Loc : constant Source_Ptr := Sloc (Typ);
3037 begin
3038 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
3040 return
3041 Make_Function_Specification (Loc,
3042 Defining_Unit_Name =>
3043 Make_Defining_Identifier (Loc, Name_uDisp_Get_Task_Id),
3044 Parameter_Specifications => New_List (
3045 Make_Parameter_Specification (Loc,
3046 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uT),
3047 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
3048 Result_Definition =>
3049 New_Occurrence_Of (RTE (RE_Address), Loc));
3050 end Make_Disp_Get_Task_Id_Spec;
3052 ----------------------------
3053 -- Make_Disp_Requeue_Body --
3054 ----------------------------
3056 function Make_Disp_Requeue_Body
3057 (Typ : Entity_Id) return Node_Id
3059 Loc : constant Source_Ptr := Sloc (Typ);
3060 Conc_Typ : Entity_Id := Empty;
3061 Stmts : constant List_Id := New_List;
3063 begin
3064 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
3066 -- Null body is generated for interface types and non-concurrent
3067 -- tagged types.
3069 if Is_Interface (Typ)
3070 or else not Is_Concurrent_Record_Type (Typ)
3071 then
3072 return
3073 Make_Subprogram_Body (Loc,
3074 Specification => Make_Disp_Requeue_Spec (Typ),
3075 Declarations => No_List,
3076 Handled_Statement_Sequence =>
3077 Make_Handled_Sequence_Of_Statements (Loc,
3078 New_List (Make_Null_Statement (Loc))));
3079 end if;
3081 Conc_Typ := Corresponding_Concurrent_Type (Typ);
3083 if Ekind (Conc_Typ) = E_Protected_Type then
3085 -- Generate statements:
3086 -- if F then
3087 -- System.Tasking.Protected_Objects.Operations.
3088 -- Requeue_Protected_Entry
3089 -- (Protection_Entries_Access (P),
3090 -- O._object'Unchecked_Access,
3091 -- Protected_Entry_Index (I),
3092 -- A);
3093 -- else
3094 -- System.Tasking.Protected_Objects.Operations.
3095 -- Requeue_Task_To_Protected_Entry
3096 -- (O._object'Unchecked_Access,
3097 -- Protected_Entry_Index (I),
3098 -- A);
3099 -- end if;
3101 if Restriction_Active (No_Entry_Queue) then
3102 Append_To (Stmts, Make_Null_Statement (Loc));
3103 else
3104 Append_To (Stmts,
3105 Make_If_Statement (Loc,
3106 Condition => Make_Identifier (Loc, Name_uF),
3108 Then_Statements =>
3109 New_List (
3111 -- Call to Requeue_Protected_Entry
3113 Make_Procedure_Call_Statement (Loc,
3114 Name =>
3115 New_Occurrence_Of
3116 (RTE (RE_Requeue_Protected_Entry), Loc),
3117 Parameter_Associations =>
3118 New_List (
3120 Make_Unchecked_Type_Conversion (Loc, -- PEA (P)
3121 Subtype_Mark =>
3122 New_Occurrence_Of (
3123 RTE (RE_Protection_Entries_Access), Loc),
3124 Expression =>
3125 Make_Identifier (Loc, Name_uP)),
3127 Make_Attribute_Reference (Loc, -- O._object'Acc
3128 Attribute_Name =>
3129 Name_Unchecked_Access,
3130 Prefix =>
3131 Make_Selected_Component (Loc,
3132 Prefix =>
3133 Make_Identifier (Loc, Name_uO),
3134 Selector_Name =>
3135 Make_Identifier (Loc, Name_uObject))),
3137 Make_Unchecked_Type_Conversion (Loc, -- entry index
3138 Subtype_Mark =>
3139 New_Occurrence_Of
3140 (RTE (RE_Protected_Entry_Index), Loc),
3141 Expression => Make_Identifier (Loc, Name_uI)),
3143 Make_Identifier (Loc, Name_uA)))), -- abort status
3145 Else_Statements =>
3146 New_List (
3148 -- Call to Requeue_Task_To_Protected_Entry
3150 Make_Procedure_Call_Statement (Loc,
3151 Name =>
3152 New_Occurrence_Of
3153 (RTE (RE_Requeue_Task_To_Protected_Entry), Loc),
3154 Parameter_Associations =>
3155 New_List (
3157 Make_Attribute_Reference (Loc, -- O._object'Acc
3158 Attribute_Name => Name_Unchecked_Access,
3159 Prefix =>
3160 Make_Selected_Component (Loc,
3161 Prefix =>
3162 Make_Identifier (Loc, Name_uO),
3163 Selector_Name =>
3164 Make_Identifier (Loc, Name_uObject))),
3166 Make_Unchecked_Type_Conversion (Loc, -- entry index
3167 Subtype_Mark =>
3168 New_Occurrence_Of
3169 (RTE (RE_Protected_Entry_Index), Loc),
3170 Expression => Make_Identifier (Loc, Name_uI)),
3172 Make_Identifier (Loc, Name_uA)))))); -- abort status
3173 end if;
3175 else
3176 pragma Assert (Is_Task_Type (Conc_Typ));
3178 -- Generate:
3179 -- if F then
3180 -- System.Tasking.Rendezvous.Requeue_Protected_To_Task_Entry
3181 -- (Protection_Entries_Access (P),
3182 -- O._task_id,
3183 -- Task_Entry_Index (I),
3184 -- A);
3185 -- else
3186 -- System.Tasking.Rendezvous.Requeue_Task_Entry
3187 -- (O._task_id,
3188 -- Task_Entry_Index (I),
3189 -- A);
3190 -- end if;
3192 Append_To (Stmts,
3193 Make_If_Statement (Loc,
3194 Condition => Make_Identifier (Loc, Name_uF),
3196 Then_Statements => New_List (
3198 -- Call to Requeue_Protected_To_Task_Entry
3200 Make_Procedure_Call_Statement (Loc,
3201 Name =>
3202 New_Occurrence_Of
3203 (RTE (RE_Requeue_Protected_To_Task_Entry), Loc),
3205 Parameter_Associations => New_List (
3207 Make_Unchecked_Type_Conversion (Loc, -- PEA (P)
3208 Subtype_Mark =>
3209 New_Occurrence_Of
3210 (RTE (RE_Protection_Entries_Access), Loc),
3211 Expression => Make_Identifier (Loc, Name_uP)),
3213 Make_Selected_Component (Loc, -- O._task_id
3214 Prefix => Make_Identifier (Loc, Name_uO),
3215 Selector_Name => Make_Identifier (Loc, Name_uTask_Id)),
3217 Make_Unchecked_Type_Conversion (Loc, -- entry index
3218 Subtype_Mark =>
3219 New_Occurrence_Of (RTE (RE_Task_Entry_Index), Loc),
3220 Expression => Make_Identifier (Loc, Name_uI)),
3222 Make_Identifier (Loc, Name_uA)))), -- abort status
3224 Else_Statements => New_List (
3226 -- Call to Requeue_Task_Entry
3228 Make_Procedure_Call_Statement (Loc,
3229 Name =>
3230 New_Occurrence_Of (RTE (RE_Requeue_Task_Entry), Loc),
3232 Parameter_Associations => New_List (
3234 Make_Selected_Component (Loc, -- O._task_id
3235 Prefix => Make_Identifier (Loc, Name_uO),
3236 Selector_Name => Make_Identifier (Loc, Name_uTask_Id)),
3238 Make_Unchecked_Type_Conversion (Loc, -- entry index
3239 Subtype_Mark =>
3240 New_Occurrence_Of (RTE (RE_Task_Entry_Index), Loc),
3241 Expression => Make_Identifier (Loc, Name_uI)),
3243 Make_Identifier (Loc, Name_uA)))))); -- abort status
3244 end if;
3246 -- Even though no declarations are needed in both cases, we allocate
3247 -- a list for entities added by Freeze.
3249 return
3250 Make_Subprogram_Body (Loc,
3251 Specification => Make_Disp_Requeue_Spec (Typ),
3252 Declarations => New_List,
3253 Handled_Statement_Sequence =>
3254 Make_Handled_Sequence_Of_Statements (Loc, Stmts));
3255 end Make_Disp_Requeue_Body;
3257 ----------------------------
3258 -- Make_Disp_Requeue_Spec --
3259 ----------------------------
3261 function Make_Disp_Requeue_Spec
3262 (Typ : Entity_Id) return Node_Id
3264 Loc : constant Source_Ptr := Sloc (Typ);
3266 begin
3267 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
3269 -- O : in out Typ; - Object parameter
3270 -- F : Boolean; - Protected (True) / task (False) flag
3271 -- P : Address; - Protection_Entries_Access value
3272 -- I : Entry_Index - Index of entry call
3273 -- A : Boolean - Abort flag
3275 -- Note that the Protection_Entries_Access value is represented as a
3276 -- System.Address in order to avoid dragging in the tasking runtime
3277 -- when compiling sources without tasking constructs.
3279 return
3280 Make_Procedure_Specification (Loc,
3281 Defining_Unit_Name =>
3282 Make_Defining_Identifier (Loc, Name_uDisp_Requeue),
3284 Parameter_Specifications => New_List (
3286 Make_Parameter_Specification (Loc, -- O
3287 Defining_Identifier =>
3288 Make_Defining_Identifier (Loc, Name_uO),
3289 Parameter_Type =>
3290 New_Occurrence_Of (Typ, Loc),
3291 In_Present => True,
3292 Out_Present => True),
3294 Make_Parameter_Specification (Loc, -- F
3295 Defining_Identifier =>
3296 Make_Defining_Identifier (Loc, Name_uF),
3297 Parameter_Type =>
3298 New_Occurrence_Of (Standard_Boolean, Loc)),
3300 Make_Parameter_Specification (Loc, -- P
3301 Defining_Identifier =>
3302 Make_Defining_Identifier (Loc, Name_uP),
3303 Parameter_Type =>
3304 New_Occurrence_Of (RTE (RE_Address), Loc)),
3306 Make_Parameter_Specification (Loc, -- I
3307 Defining_Identifier =>
3308 Make_Defining_Identifier (Loc, Name_uI),
3309 Parameter_Type =>
3310 New_Occurrence_Of (Standard_Integer, Loc)),
3312 Make_Parameter_Specification (Loc, -- A
3313 Defining_Identifier =>
3314 Make_Defining_Identifier (Loc, Name_uA),
3315 Parameter_Type =>
3316 New_Occurrence_Of (Standard_Boolean, Loc))));
3317 end Make_Disp_Requeue_Spec;
3319 ---------------------------------
3320 -- Make_Disp_Timed_Select_Body --
3321 ---------------------------------
3323 -- For interface types, generate:
3325 -- procedure _Disp_Timed_Select
3326 -- (T : in out <Typ>;
3327 -- S : Integer;
3328 -- P : System.Address;
3329 -- D : Duration;
3330 -- M : Integer;
3331 -- C : out Ada.Tags.Prim_Op_Kind;
3332 -- F : out Boolean)
3333 -- is
3334 -- begin
3335 -- F := False;
3336 -- C := Ada.Tags.POK_Function;
3337 -- end _Disp_Timed_Select;
3339 -- For protected types, generate:
3341 -- procedure _Disp_Timed_Select
3342 -- (T : in out <Typ>;
3343 -- S : Integer;
3344 -- P : System.Address;
3345 -- D : Duration;
3346 -- M : Integer;
3347 -- C : out Ada.Tags.Prim_Op_Kind;
3348 -- F : out Boolean)
3349 -- is
3350 -- I : Integer;
3352 -- begin
3353 -- C := Ada.Tags.Get_Prim_Op_Kind (Ada.Tags.Tag (<Typ>VP), S);
3355 -- if C = Ada.Tags.POK_Procedure
3356 -- or else C = Ada.Tags.POK_Protected_Procedure
3357 -- or else C = Ada.Tags.POK_Task_Procedure
3358 -- then
3359 -- F := True;
3360 -- return;
3361 -- end if;
3363 -- I := Ada.Tags.Get_Entry_Index (Ada.Tags.Tag (<Typ>VP), S);
3364 -- System.Tasking.Protected_Objects.Operations.
3365 -- Timed_Protected_Entry_Call
3366 -- (T._object'Access,
3367 -- System.Tasking.Protected_Objects.Protected_Entry_Index (I),
3368 -- P,
3369 -- D,
3370 -- M,
3371 -- F);
3372 -- end _Disp_Timed_Select;
3374 -- For task types, generate:
3376 -- procedure _Disp_Timed_Select
3377 -- (T : in out <Typ>;
3378 -- S : Integer;
3379 -- P : System.Address;
3380 -- D : Duration;
3381 -- M : Integer;
3382 -- C : out Ada.Tags.Prim_Op_Kind;
3383 -- F : out Boolean)
3384 -- is
3385 -- I : Integer;
3387 -- begin
3388 -- I := Ada.Tags.Get_Entry_Index (Ada.Tags.Tag (<Typ>VP), S);
3389 -- System.Tasking.Rendezvous.Timed_Task_Entry_Call
3390 -- (T._task_id,
3391 -- System.Tasking.Task_Entry_Index (I),
3392 -- P,
3393 -- D,
3394 -- M,
3395 -- F);
3396 -- end _Disp_Time_Select;
3398 function Make_Disp_Timed_Select_Body
3399 (Typ : Entity_Id) return Node_Id
3401 Loc : constant Source_Ptr := Sloc (Typ);
3402 Conc_Typ : Entity_Id := Empty;
3403 Decls : constant List_Id := New_List;
3404 Obj_Ref : Node_Id;
3405 Stmts : constant List_Id := New_List;
3406 Tag_Node : Node_Id;
3408 begin
3409 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
3411 -- Null body is generated for interface types
3413 if Is_Interface (Typ) then
3414 return
3415 Make_Subprogram_Body (Loc,
3416 Specification => Make_Disp_Timed_Select_Spec (Typ),
3417 Declarations => New_List,
3418 Handled_Statement_Sequence =>
3419 Make_Handled_Sequence_Of_Statements (Loc,
3420 New_List (
3421 Make_Assignment_Statement (Loc,
3422 Name => Make_Identifier (Loc, Name_uF),
3423 Expression => New_Occurrence_Of (Standard_False, Loc)))));
3424 end if;
3426 if Is_Concurrent_Record_Type (Typ) then
3427 Conc_Typ := Corresponding_Concurrent_Type (Typ);
3429 -- Generate:
3430 -- I : Integer;
3432 -- where I will be used to capture the entry index of the primitive
3433 -- wrapper at position S.
3435 Append_To (Decls,
3436 Make_Object_Declaration (Loc,
3437 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uI),
3438 Object_Definition =>
3439 New_Occurrence_Of (Standard_Integer, Loc)));
3441 -- Generate:
3442 -- C := Get_Prim_Op_Kind (tag! (<type>VP), S);
3444 -- if C = POK_Procedure
3445 -- or else C = POK_Protected_Procedure
3446 -- or else C = POK_Task_Procedure;
3447 -- then
3448 -- F := True;
3449 -- return;
3450 -- end if;
3452 Build_Common_Dispatching_Select_Statements (Typ, Stmts);
3454 -- Generate:
3455 -- I := Get_Entry_Index (tag! (<type>VP), S);
3457 -- I is the entry index and S is the dispatch table slot
3459 if Tagged_Type_Expansion then
3460 Tag_Node :=
3461 Unchecked_Convert_To (RTE (RE_Tag),
3462 New_Occurrence_Of
3463 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc));
3465 else
3466 Tag_Node :=
3467 Make_Attribute_Reference (Loc,
3468 Prefix => New_Occurrence_Of (Typ, Loc),
3469 Attribute_Name => Name_Tag);
3470 end if;
3472 Append_To (Stmts,
3473 Make_Assignment_Statement (Loc,
3474 Name => Make_Identifier (Loc, Name_uI),
3475 Expression =>
3476 Make_Function_Call (Loc,
3477 Name => New_Occurrence_Of (RTE (RE_Get_Entry_Index), Loc),
3478 Parameter_Associations => New_List (
3479 Tag_Node,
3480 Make_Identifier (Loc, Name_uS)))));
3482 -- Protected case
3484 if Ekind (Conc_Typ) = E_Protected_Type then
3486 -- Build T._object'Access
3488 Obj_Ref :=
3489 Make_Attribute_Reference (Loc,
3490 Attribute_Name => Name_Unchecked_Access,
3491 Prefix =>
3492 Make_Selected_Component (Loc,
3493 Prefix => Make_Identifier (Loc, Name_uT),
3494 Selector_Name => Make_Identifier (Loc, Name_uObject)));
3496 -- Normal case, No_Entry_Queue restriction not active. In this
3497 -- case we generate:
3499 -- Timed_Protected_Entry_Call
3500 -- (T._object'access,
3501 -- Protected_Entry_Index! (I),
3502 -- P, D, M, F);
3504 -- where T is the protected object, I is the entry index, P are
3505 -- the wrapped parameters, D is the delay amount, M is the delay
3506 -- mode and F is the status flag.
3508 -- Historically, there was also an implementation for single
3509 -- entry protected types (in s-tposen). However, it was removed
3510 -- by also testing for no No_Select_Statements restriction in
3511 -- Exp_Utils.Corresponding_Runtime_Package. This simplified the
3512 -- implementation of s-tposen.adb and provided consistency between
3513 -- all versions of System.Tasking.Protected_Objects.Single_Entry
3514 -- (s-tposen*.adb).
3516 case Corresponding_Runtime_Package (Conc_Typ) is
3517 when System_Tasking_Protected_Objects_Entries =>
3518 Append_To (Stmts,
3519 Make_Procedure_Call_Statement (Loc,
3520 Name =>
3521 New_Occurrence_Of
3522 (RTE (RE_Timed_Protected_Entry_Call), Loc),
3523 Parameter_Associations => New_List (
3524 Obj_Ref,
3526 Make_Unchecked_Type_Conversion (Loc, -- entry index
3527 Subtype_Mark =>
3528 New_Occurrence_Of
3529 (RTE (RE_Protected_Entry_Index), Loc),
3530 Expression => Make_Identifier (Loc, Name_uI)),
3532 Make_Identifier (Loc, Name_uP), -- parameter block
3533 Make_Identifier (Loc, Name_uD), -- delay
3534 Make_Identifier (Loc, Name_uM), -- delay mode
3535 Make_Identifier (Loc, Name_uF)))); -- status flag
3537 when others =>
3538 raise Program_Error;
3539 end case;
3541 -- Task case
3543 else
3544 pragma Assert (Ekind (Conc_Typ) = E_Task_Type);
3546 -- Generate:
3547 -- Timed_Task_Entry_Call (
3548 -- T._task_id,
3549 -- Task_Entry_Index! (I),
3550 -- P,
3551 -- D,
3552 -- M,
3553 -- F);
3555 -- where T is the task object, I is the entry index, P are the
3556 -- wrapped parameters, D is the delay amount, M is the delay
3557 -- mode and F is the status flag.
3559 Append_To (Stmts,
3560 Make_Procedure_Call_Statement (Loc,
3561 Name =>
3562 New_Occurrence_Of (RTE (RE_Timed_Task_Entry_Call), Loc),
3564 Parameter_Associations => New_List (
3565 Make_Selected_Component (Loc, -- T._task_id
3566 Prefix => Make_Identifier (Loc, Name_uT),
3567 Selector_Name => Make_Identifier (Loc, Name_uTask_Id)),
3569 Make_Unchecked_Type_Conversion (Loc, -- entry index
3570 Subtype_Mark =>
3571 New_Occurrence_Of (RTE (RE_Task_Entry_Index), Loc),
3572 Expression => Make_Identifier (Loc, Name_uI)),
3574 Make_Identifier (Loc, Name_uP), -- parameter block
3575 Make_Identifier (Loc, Name_uD), -- delay
3576 Make_Identifier (Loc, Name_uM), -- delay mode
3577 Make_Identifier (Loc, Name_uF)))); -- status flag
3578 end if;
3580 else
3581 -- Initialize out parameters
3583 Append_To (Stmts,
3584 Make_Assignment_Statement (Loc,
3585 Name => Make_Identifier (Loc, Name_uF),
3586 Expression => New_Occurrence_Of (Standard_False, Loc)));
3587 Append_To (Stmts,
3588 Make_Assignment_Statement (Loc,
3589 Name => Make_Identifier (Loc, Name_uC),
3590 Expression => New_Occurrence_Of (RTE (RE_POK_Function), Loc)));
3591 end if;
3593 return
3594 Make_Subprogram_Body (Loc,
3595 Specification => Make_Disp_Timed_Select_Spec (Typ),
3596 Declarations => Decls,
3597 Handled_Statement_Sequence =>
3598 Make_Handled_Sequence_Of_Statements (Loc, Stmts));
3599 end Make_Disp_Timed_Select_Body;
3601 ---------------------------------
3602 -- Make_Disp_Timed_Select_Spec --
3603 ---------------------------------
3605 function Make_Disp_Timed_Select_Spec
3606 (Typ : Entity_Id) return Node_Id
3608 Loc : constant Source_Ptr := Sloc (Typ);
3609 Def_Id : constant Node_Id :=
3610 Make_Defining_Identifier (Loc,
3611 Name_uDisp_Timed_Select);
3612 Params : constant List_Id := New_List;
3614 begin
3615 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
3617 -- T : in out Typ; -- Object parameter
3618 -- S : Integer; -- Primitive operation slot
3619 -- P : Address; -- Wrapped parameters
3620 -- D : Duration; -- Delay
3621 -- M : Integer; -- Delay Mode
3622 -- C : out Prim_Op_Kind; -- Call kind
3623 -- F : out Boolean; -- Status flag
3625 Append_List_To (Params, New_List (
3627 Make_Parameter_Specification (Loc,
3628 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uT),
3629 Parameter_Type => New_Occurrence_Of (Typ, Loc),
3630 In_Present => True,
3631 Out_Present => True),
3633 Make_Parameter_Specification (Loc,
3634 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uS),
3635 Parameter_Type => New_Occurrence_Of (Standard_Integer, Loc)),
3637 Make_Parameter_Specification (Loc,
3638 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uP),
3639 Parameter_Type => New_Occurrence_Of (RTE (RE_Address), Loc)),
3641 Make_Parameter_Specification (Loc,
3642 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uD),
3643 Parameter_Type => New_Occurrence_Of (Standard_Duration, Loc)),
3645 Make_Parameter_Specification (Loc,
3646 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uM),
3647 Parameter_Type => New_Occurrence_Of (Standard_Integer, Loc)),
3649 Make_Parameter_Specification (Loc,
3650 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uC),
3651 Parameter_Type =>
3652 New_Occurrence_Of (RTE (RE_Prim_Op_Kind), Loc),
3653 Out_Present => True)));
3655 Append_To (Params,
3656 Make_Parameter_Specification (Loc,
3657 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uF),
3658 Parameter_Type => New_Occurrence_Of (Standard_Boolean, Loc),
3659 Out_Present => True));
3661 return
3662 Make_Procedure_Specification (Loc,
3663 Defining_Unit_Name => Def_Id,
3664 Parameter_Specifications => Params);
3665 end Make_Disp_Timed_Select_Spec;
3667 -------------
3668 -- Make_DT --
3669 -------------
3671 -- The frontend supports two models for expanding dispatch tables
3672 -- associated with library-level defined tagged types: statically and
3673 -- non-statically allocated dispatch tables. In the former case the object
3674 -- containing the dispatch table is constant and it is initialized by means
3675 -- of a positional aggregate. In the latter case, the object containing
3676 -- the dispatch table is a variable which is initialized by means of
3677 -- assignments.
3679 -- In case of locally defined tagged types, the object containing the
3680 -- object containing the dispatch table is always a variable (instead of a
3681 -- constant). This is currently required to give support to late overriding
3682 -- of primitives. For example:
3684 -- procedure Example is
3685 -- package Pkg is
3686 -- type T1 is tagged null record;
3687 -- procedure Prim (O : T1);
3688 -- end Pkg;
3690 -- type T2 is new Pkg.T1 with null record;
3691 -- procedure Prim (X : T2) is -- late overriding
3692 -- begin
3693 -- ...
3694 -- ...
3695 -- end;
3697 -- WARNING: This routine manages Ghost regions. Return statements must be
3698 -- replaced by gotos which jump to the end of the routine and restore the
3699 -- Ghost mode.
3701 function Make_DT (Typ : Entity_Id; N : Node_Id := Empty) return List_Id is
3702 Loc : constant Source_Ptr := Sloc (Typ);
3704 Max_Predef_Prims : constant Int :=
3705 UI_To_Int
3706 (Intval
3707 (Expression
3708 (Parent (RTE (RE_Max_Predef_Prims)))));
3710 DT_Decl : constant Elist_Id := New_Elmt_List;
3711 DT_Aggr : constant Elist_Id := New_Elmt_List;
3712 -- Entities marked with attribute Is_Dispatch_Table_Entity
3714 Dummy_Object : Entity_Id := Empty;
3715 -- Extra nonexistent object of type Typ internally used to compute the
3716 -- offset to the components that reference secondary dispatch tables.
3717 -- Used to statically allocate secondary dispatch tables.
3719 procedure Check_Premature_Freezing
3720 (Subp : Entity_Id;
3721 Tagged_Type : Entity_Id;
3722 Typ : Entity_Id);
3723 -- Verify that all untagged types in the profile of a subprogram are
3724 -- frozen at the point the subprogram is frozen. This enforces the rule
3725 -- on RM 13.14 (14) as modified by AI05-019. At the point a subprogram
3726 -- is frozen, enough must be known about it to build the activation
3727 -- record for it, which requires at least that the size of all
3728 -- parameters be known. Controlling arguments are by-reference,
3729 -- and therefore the rule only applies to untagged types. Typical
3730 -- violation of the rule involves an object declaration that freezes a
3731 -- tagged type, when one of its primitive operations has a type in its
3732 -- profile whose full view has not been analyzed yet. More complex cases
3733 -- involve composite types that have one private unfrozen subcomponent.
3735 procedure Export_DT (Typ : Entity_Id; DT : Entity_Id; Index : Nat := 0);
3736 -- Export the dispatch table DT of tagged type Typ. Required to generate
3737 -- forward references and statically allocate the table. For primary
3738 -- dispatch tables Index is 0; for secondary dispatch tables the value
3739 -- of index must match the Suffix_Index value assigned to the table by
3740 -- Make_Tags when generating its unique external name, and it is used to
3741 -- retrieve from the Dispatch_Table_Wrappers list associated with Typ
3742 -- the external name generated by Import_DT.
3744 procedure Make_Secondary_DT
3745 (Typ : Entity_Id;
3746 Iface : Entity_Id;
3747 Iface_Comp : Node_Id;
3748 Suffix_Index : Int;
3749 Num_Iface_Prims : Nat;
3750 Iface_DT_Ptr : Entity_Id;
3751 Predef_Prims_Ptr : Entity_Id;
3752 Build_Thunks : Boolean;
3753 Result : List_Id);
3754 -- Ada 2005 (AI-251): Expand the declarations for a Secondary Dispatch
3755 -- Table of Typ associated with Iface. Each abstract interface of Typ
3756 -- has two secondary dispatch tables: one containing pointers to thunks
3757 -- and another containing pointers to the primitives covering the
3758 -- interface primitives. The former secondary table is generated when
3759 -- Build_Thunks is True, and provides common support for dispatching
3760 -- calls through interface types; the latter secondary table is
3761 -- generated when Build_Thunks is False, and provides support for
3762 -- Generic Dispatching Constructors that dispatch calls through
3763 -- interface types. When constructing this latter table the value of
3764 -- Suffix_Index is -1 to indicate that there is no need to export such
3765 -- table when building statically allocated dispatch tables; a positive
3766 -- value of Suffix_Index must match the Suffix_Index value assigned to
3767 -- this secondary dispatch table by Make_Tags when its unique external
3768 -- name was generated.
3770 ------------------------------
3771 -- Check_Premature_Freezing --
3772 ------------------------------
3774 procedure Check_Premature_Freezing
3775 (Subp : Entity_Id;
3776 Tagged_Type : Entity_Id;
3777 Typ : Entity_Id)
3779 Comp : Entity_Id;
3781 function Is_Actual_For_Formal_Incomplete_Type
3782 (T : Entity_Id) return Boolean;
3783 -- In Ada 2012, if a nested generic has an incomplete formal type,
3784 -- the actual may be (and usually is) a private type whose completion
3785 -- appears later. It is safe to build the dispatch table in this
3786 -- case, gigi will have full views available.
3788 ------------------------------------------
3789 -- Is_Actual_For_Formal_Incomplete_Type --
3790 ------------------------------------------
3792 function Is_Actual_For_Formal_Incomplete_Type
3793 (T : Entity_Id) return Boolean
3795 Gen_Par : Entity_Id;
3796 F : Node_Id;
3798 begin
3799 if not Is_Generic_Instance (Current_Scope)
3800 or else not Used_As_Generic_Actual (T)
3801 then
3802 return False;
3803 else
3804 Gen_Par := Generic_Parent (Parent (Current_Scope));
3805 end if;
3807 F :=
3808 First
3809 (Generic_Formal_Declarations
3810 (Unit_Declaration_Node (Gen_Par)));
3811 while Present (F) loop
3812 if Ekind (Defining_Identifier (F)) = E_Incomplete_Type then
3813 return True;
3814 end if;
3816 Next (F);
3817 end loop;
3819 return False;
3820 end Is_Actual_For_Formal_Incomplete_Type;
3822 -- Start of processing for Check_Premature_Freezing
3824 begin
3825 -- Note that if the type is a (subtype of) a generic actual, the
3826 -- actual will have been frozen by the instantiation.
3828 if Present (N)
3829 and then Is_Private_Type (Typ)
3830 and then No (Full_View (Typ))
3831 and then not Is_Generic_Type (Typ)
3832 and then not Is_Tagged_Type (Typ)
3833 and then not Is_Frozen (Typ)
3834 and then not Is_Generic_Actual_Type (Typ)
3835 then
3836 Error_Msg_Sloc := Sloc (Subp);
3837 Error_Msg_NE
3838 ("declaration must appear after completion of type &", N, Typ);
3839 Error_Msg_NE
3840 ("\which is an untagged type in the profile of "
3841 & "primitive operation & declared#", N, Subp);
3843 else
3844 Comp := Private_Component (Typ);
3846 if not Is_Tagged_Type (Typ)
3847 and then Present (Comp)
3848 and then not Is_Frozen (Comp)
3849 and then not Is_Actual_For_Formal_Incomplete_Type (Comp)
3850 then
3851 Error_Msg_Sloc := Sloc (Subp);
3852 Error_Msg_Node_2 := Subp;
3853 Error_Msg_Name_1 := Chars (Tagged_Type);
3854 Error_Msg_NE
3855 ("declaration must appear after completion of type &",
3856 N, Comp);
3857 Error_Msg_NE
3858 ("\which is a component of untagged type& in the profile "
3859 & "of primitive & of type % that is frozen by the "
3860 & "declaration ", N, Typ);
3861 end if;
3862 end if;
3863 end Check_Premature_Freezing;
3865 ---------------
3866 -- Export_DT --
3867 ---------------
3869 procedure Export_DT (Typ : Entity_Id; DT : Entity_Id; Index : Nat := 0)
3871 Count : Nat;
3872 Elmt : Elmt_Id;
3874 begin
3875 Set_Is_Statically_Allocated (DT);
3876 Set_Is_True_Constant (DT);
3877 Set_Is_Exported (DT);
3879 Count := 0;
3880 Elmt := First_Elmt (Dispatch_Table_Wrappers (Typ));
3881 while Count /= Index loop
3882 Next_Elmt (Elmt);
3883 Count := Count + 1;
3884 end loop;
3886 pragma Assert (Related_Type (Node (Elmt)) = Typ);
3888 Get_External_Name (Node (Elmt));
3889 Set_Interface_Name (DT,
3890 Make_String_Literal (Loc,
3891 Strval => String_From_Name_Buffer));
3893 -- Ensure proper Sprint output of this implicit importation
3895 Set_Is_Internal (DT);
3896 Set_Is_Public (DT);
3897 end Export_DT;
3899 -----------------------
3900 -- Make_Secondary_DT --
3901 -----------------------
3903 procedure Make_Secondary_DT
3904 (Typ : Entity_Id;
3905 Iface : Entity_Id;
3906 Iface_Comp : Node_Id;
3907 Suffix_Index : Int;
3908 Num_Iface_Prims : Nat;
3909 Iface_DT_Ptr : Entity_Id;
3910 Predef_Prims_Ptr : Entity_Id;
3911 Build_Thunks : Boolean;
3912 Result : List_Id)
3914 Loc : constant Source_Ptr := Sloc (Typ);
3915 Exporting_Table : constant Boolean :=
3916 Building_Static_DT (Typ)
3917 and then Suffix_Index > 0;
3918 Iface_DT : constant Entity_Id := Make_Temporary (Loc, 'T');
3919 Predef_Prims : constant Entity_Id := Make_Temporary (Loc, 'R');
3920 DT_Constr_List : List_Id;
3921 DT_Aggr_List : List_Id;
3922 Empty_DT : Boolean := False;
3923 Nb_Predef_Prims : Nat := 0;
3924 Nb_Prim : Nat;
3925 New_Node : Node_Id;
3926 OSD : Entity_Id;
3927 OSD_Aggr_List : List_Id;
3928 Pos : Nat;
3929 Prim : Entity_Id;
3930 Prim_Elmt : Elmt_Id;
3931 Prim_Ops_Aggr_List : List_Id;
3933 begin
3934 -- Handle cases in which we do not generate statically allocated
3935 -- dispatch tables.
3937 if not Building_Static_DT (Typ) then
3938 Set_Ekind (Predef_Prims, E_Variable);
3939 Set_Ekind (Iface_DT, E_Variable);
3941 -- Statically allocated dispatch tables and related entities are
3942 -- constants.
3944 else
3945 Set_Ekind (Predef_Prims, E_Constant);
3946 Set_Is_Statically_Allocated (Predef_Prims);
3947 Set_Is_True_Constant (Predef_Prims);
3949 Set_Ekind (Iface_DT, E_Constant);
3950 Set_Is_Statically_Allocated (Iface_DT);
3951 Set_Is_True_Constant (Iface_DT);
3952 end if;
3954 -- Calculate the number of slots of the dispatch table. If the number
3955 -- of primitives of Typ is 0 we reserve a dummy single entry for its
3956 -- DT because at run time the pointer to this dummy entry will be
3957 -- used as the tag.
3959 if Num_Iface_Prims = 0 then
3960 Empty_DT := True;
3961 Nb_Prim := 1;
3962 else
3963 Nb_Prim := Num_Iface_Prims;
3964 end if;
3966 -- Generate:
3968 -- Predef_Prims : Address_Array (1 .. Default_Prim_Ops_Count) :=
3969 -- (predef-prim-op-thunk-1'address,
3970 -- predef-prim-op-thunk-2'address,
3971 -- ...
3972 -- predef-prim-op-thunk-n'address);
3973 -- for Predef_Prims'Alignment use Address'Alignment
3975 -- Stage 1: Calculate the number of predefined primitives
3977 if not Building_Static_DT (Typ) then
3978 Nb_Predef_Prims := Max_Predef_Prims;
3979 else
3980 Prim_Elmt := First_Elmt (Primitive_Operations (Typ));
3981 while Present (Prim_Elmt) loop
3982 Prim := Node (Prim_Elmt);
3984 if Is_Predefined_Dispatching_Operation (Prim)
3985 and then not Is_Abstract_Subprogram (Prim)
3986 then
3987 Pos := UI_To_Int (DT_Position (Prim));
3989 if Pos > Nb_Predef_Prims then
3990 Nb_Predef_Prims := Pos;
3991 end if;
3992 end if;
3994 Next_Elmt (Prim_Elmt);
3995 end loop;
3996 end if;
3998 if Generate_SCIL then
3999 Nb_Predef_Prims := 0;
4000 end if;
4002 -- Stage 2: Create the thunks associated with the predefined
4003 -- primitives and save their entity to fill the aggregate.
4005 declare
4006 Prim_Table : array (Nat range 1 .. Nb_Predef_Prims) of Entity_Id;
4007 Decl : Node_Id;
4008 Thunk_Id : Entity_Id;
4009 Thunk_Code : Node_Id;
4011 begin
4012 Prim_Ops_Aggr_List := New_List;
4013 Prim_Table := (others => Empty);
4015 if Building_Static_DT (Typ) then
4016 Prim_Elmt := First_Elmt (Primitive_Operations (Typ));
4017 while Present (Prim_Elmt) loop
4018 Prim := Node (Prim_Elmt);
4020 if Is_Predefined_Dispatching_Operation (Prim)
4021 and then not Is_Abstract_Subprogram (Prim)
4022 and then not Is_Eliminated (Prim)
4023 and then not Generate_SCIL
4024 and then not Present (Prim_Table
4025 (UI_To_Int (DT_Position (Prim))))
4026 then
4027 if not Build_Thunks then
4028 Prim_Table (UI_To_Int (DT_Position (Prim))) :=
4029 Alias (Prim);
4031 else
4032 Expand_Interface_Thunk
4033 (Ultimate_Alias (Prim), Thunk_Id, Thunk_Code);
4035 if Present (Thunk_Id) then
4036 Append_To (Result, Thunk_Code);
4037 Prim_Table (UI_To_Int (DT_Position (Prim))) :=
4038 Thunk_Id;
4039 end if;
4040 end if;
4041 end if;
4043 Next_Elmt (Prim_Elmt);
4044 end loop;
4045 end if;
4047 for J in Prim_Table'Range loop
4048 if Present (Prim_Table (J)) then
4049 New_Node :=
4050 Unchecked_Convert_To (RTE (RE_Prim_Ptr),
4051 Make_Attribute_Reference (Loc,
4052 Prefix => New_Occurrence_Of (Prim_Table (J), Loc),
4053 Attribute_Name => Name_Unrestricted_Access));
4054 else
4055 New_Node := Make_Null (Loc);
4056 end if;
4058 Append_To (Prim_Ops_Aggr_List, New_Node);
4059 end loop;
4061 New_Node :=
4062 Make_Aggregate (Loc, Expressions => Prim_Ops_Aggr_List);
4064 -- Remember aggregates initializing dispatch tables
4066 Append_Elmt (New_Node, DT_Aggr);
4068 Decl :=
4069 Make_Subtype_Declaration (Loc,
4070 Defining_Identifier => Make_Temporary (Loc, 'S'),
4071 Subtype_Indication =>
4072 New_Occurrence_Of (RTE (RE_Address_Array), Loc));
4074 Append_To (Result, Decl);
4076 Append_To (Result,
4077 Make_Object_Declaration (Loc,
4078 Defining_Identifier => Predef_Prims,
4079 Constant_Present => Building_Static_DT (Typ),
4080 Aliased_Present => True,
4081 Object_Definition => New_Occurrence_Of
4082 (Defining_Identifier (Decl), Loc),
4083 Expression => New_Node));
4085 Append_To (Result,
4086 Make_Attribute_Definition_Clause (Loc,
4087 Name => New_Occurrence_Of (Predef_Prims, Loc),
4088 Chars => Name_Alignment,
4089 Expression =>
4090 Make_Attribute_Reference (Loc,
4091 Prefix =>
4092 New_Occurrence_Of (RTE (RE_Integer_Address), Loc),
4093 Attribute_Name => Name_Alignment)));
4094 end;
4096 -- Generate
4098 -- OSD : Ada.Tags.Object_Specific_Data (Nb_Prims) :=
4099 -- (OSD_Table => (1 => <value>,
4100 -- ...
4101 -- N => <value>));
4103 -- Iface_DT : Dispatch_Table (Nb_Prims) :=
4104 -- ([ Signature => <sig-value> ],
4105 -- Tag_Kind => <tag_kind-value>,
4106 -- Predef_Prims => Predef_Prims'Address,
4107 -- Offset_To_Top => 0,
4108 -- OSD => OSD'Address,
4109 -- Prims_Ptr => (prim-op-1'address,
4110 -- prim-op-2'address,
4111 -- ...
4112 -- prim-op-n'address));
4113 -- for Iface_DT'Alignment use Address'Alignment;
4115 -- Stage 3: Initialize the discriminant and the record components
4117 DT_Constr_List := New_List;
4118 DT_Aggr_List := New_List;
4120 -- Nb_Prim
4122 Append_To (DT_Constr_List, Make_Integer_Literal (Loc, Nb_Prim));
4123 Append_To (DT_Aggr_List, Make_Integer_Literal (Loc, Nb_Prim));
4125 -- Signature
4127 if RTE_Record_Component_Available (RE_Signature) then
4128 Append_To (DT_Aggr_List,
4129 New_Occurrence_Of (RTE (RE_Secondary_DT), Loc));
4130 end if;
4132 -- Tag_Kind
4134 if RTE_Record_Component_Available (RE_Tag_Kind) then
4135 Append_To (DT_Aggr_List, Tagged_Kind (Typ));
4136 end if;
4138 -- Predef_Prims
4140 Append_To (DT_Aggr_List,
4141 Make_Attribute_Reference (Loc,
4142 Prefix => New_Occurrence_Of (Predef_Prims, Loc),
4143 Attribute_Name => Name_Address));
4145 -- If the location of the component that references this secondary
4146 -- dispatch table is variable then we have not declared the internal
4147 -- dummy object; the value of Offset_To_Top will be set by the init
4148 -- subprogram.
4150 if No (Dummy_Object) then
4151 Append_To (DT_Aggr_List, Make_Integer_Literal (Loc, 0));
4153 else
4154 Append_To (DT_Aggr_List,
4155 Make_Op_Minus (Loc,
4156 Make_Attribute_Reference (Loc,
4157 Prefix =>
4158 Make_Selected_Component (Loc,
4159 Prefix =>
4160 New_Occurrence_Of (Dummy_Object, Loc),
4161 Selector_Name =>
4162 New_Occurrence_Of (Iface_Comp, Loc)),
4163 Attribute_Name => Name_Position)));
4164 end if;
4166 -- Generate the Object Specific Data table required to dispatch calls
4167 -- through synchronized interfaces.
4169 if Empty_DT
4170 or else Is_Abstract_Type (Typ)
4171 or else Is_Controlled (Typ)
4172 or else Restriction_Active (No_Dispatching_Calls)
4173 or else not Is_Limited_Type (Typ)
4174 or else not Has_Interfaces (Typ)
4175 or else not Build_Thunks
4176 or else not RTE_Record_Component_Available (RE_OSD_Table)
4177 then
4178 -- No OSD table required
4180 Append_To (DT_Aggr_List,
4181 New_Occurrence_Of (RTE (RE_Null_Address), Loc));
4183 else
4184 OSD_Aggr_List := New_List;
4186 declare
4187 Prim_Table : array (Nat range 1 .. Nb_Prim) of Entity_Id;
4188 Prim : Entity_Id;
4189 Prim_Alias : Entity_Id;
4190 Prim_Elmt : Elmt_Id;
4191 E : Entity_Id;
4192 Count : Nat := 0;
4193 Pos : Nat;
4195 begin
4196 Prim_Table := (others => Empty);
4197 Prim_Alias := Empty;
4199 Prim_Elmt := First_Elmt (Primitive_Operations (Typ));
4200 while Present (Prim_Elmt) loop
4201 Prim := Node (Prim_Elmt);
4203 if Present (Interface_Alias (Prim))
4204 and then Find_Dispatching_Type
4205 (Interface_Alias (Prim)) = Iface
4206 then
4207 Prim_Alias := Interface_Alias (Prim);
4208 E := Ultimate_Alias (Prim);
4209 Pos := UI_To_Int (DT_Position (Prim_Alias));
4211 if Present (Prim_Table (Pos)) then
4212 pragma Assert (Prim_Table (Pos) = E);
4213 null;
4215 else
4216 Prim_Table (Pos) := E;
4218 Append_To (OSD_Aggr_List,
4219 Make_Component_Association (Loc,
4220 Choices => New_List (
4221 Make_Integer_Literal (Loc,
4222 DT_Position (Prim_Alias))),
4223 Expression =>
4224 Make_Integer_Literal (Loc,
4225 DT_Position (Alias (Prim)))));
4227 Count := Count + 1;
4228 end if;
4229 end if;
4231 Next_Elmt (Prim_Elmt);
4232 end loop;
4233 pragma Assert (Count = Nb_Prim);
4234 end;
4236 OSD := Make_Temporary (Loc, 'I');
4238 Append_To (Result,
4239 Make_Object_Declaration (Loc,
4240 Defining_Identifier => OSD,
4241 Object_Definition =>
4242 Make_Subtype_Indication (Loc,
4243 Subtype_Mark =>
4244 New_Occurrence_Of (RTE (RE_Object_Specific_Data), Loc),
4245 Constraint =>
4246 Make_Index_Or_Discriminant_Constraint (Loc,
4247 Constraints => New_List (
4248 Make_Integer_Literal (Loc, Nb_Prim)))),
4250 Expression =>
4251 Make_Aggregate (Loc,
4252 Component_Associations => New_List (
4253 Make_Component_Association (Loc,
4254 Choices => New_List (
4255 New_Occurrence_Of
4256 (RTE_Record_Component (RE_OSD_Num_Prims), Loc)),
4257 Expression =>
4258 Make_Integer_Literal (Loc, Nb_Prim)),
4260 Make_Component_Association (Loc,
4261 Choices => New_List (
4262 New_Occurrence_Of
4263 (RTE_Record_Component (RE_OSD_Table), Loc)),
4264 Expression => Make_Aggregate (Loc,
4265 Component_Associations => OSD_Aggr_List))))));
4267 Append_To (Result,
4268 Make_Attribute_Definition_Clause (Loc,
4269 Name => New_Occurrence_Of (OSD, Loc),
4270 Chars => Name_Alignment,
4271 Expression =>
4272 Make_Attribute_Reference (Loc,
4273 Prefix =>
4274 New_Occurrence_Of (RTE (RE_Integer_Address), Loc),
4275 Attribute_Name => Name_Alignment)));
4277 -- In secondary dispatch tables the Typeinfo component contains
4278 -- the address of the Object Specific Data (see a-tags.ads)
4280 Append_To (DT_Aggr_List,
4281 Make_Attribute_Reference (Loc,
4282 Prefix => New_Occurrence_Of (OSD, Loc),
4283 Attribute_Name => Name_Address));
4284 end if;
4286 -- Initialize the table of primitive operations
4288 Prim_Ops_Aggr_List := New_List;
4290 if Empty_DT then
4291 Append_To (Prim_Ops_Aggr_List, Make_Null (Loc));
4293 elsif Is_Abstract_Type (Typ)
4294 or else not Building_Static_DT (Typ)
4295 then
4296 for J in 1 .. Nb_Prim loop
4297 Append_To (Prim_Ops_Aggr_List, Make_Null (Loc));
4298 end loop;
4300 else
4301 declare
4302 CPP_Nb_Prims : constant Nat := CPP_Num_Prims (Typ);
4303 E : Entity_Id;
4304 Prim_Pos : Nat;
4305 Prim_Table : array (Nat range 1 .. Nb_Prim) of Entity_Id;
4306 Thunk_Code : Node_Id;
4307 Thunk_Id : Entity_Id;
4309 begin
4310 Prim_Table := (others => Empty);
4312 Prim_Elmt := First_Elmt (Primitive_Operations (Typ));
4313 while Present (Prim_Elmt) loop
4314 Prim := Node (Prim_Elmt);
4315 E := Ultimate_Alias (Prim);
4316 Prim_Pos := UI_To_Int (DT_Position (E));
4318 -- Do not reference predefined primitives because they are
4319 -- located in a separate dispatch table; skip abstract and
4320 -- eliminated primitives; skip primitives located in the C++
4321 -- part of the dispatch table because their slot is set by
4322 -- the IC routine.
4324 if not Is_Predefined_Dispatching_Operation (Prim)
4325 and then Present (Interface_Alias (Prim))
4326 and then not Is_Abstract_Subprogram (Alias (Prim))
4327 and then not Is_Eliminated (Alias (Prim))
4328 and then (not Is_CPP_Class (Root_Type (Typ))
4329 or else Prim_Pos > CPP_Nb_Prims)
4330 and then Find_Dispatching_Type
4331 (Interface_Alias (Prim)) = Iface
4333 -- Generate the code of the thunk only if the abstract
4334 -- interface type is not an immediate ancestor of
4335 -- Tagged_Type. Otherwise the DT associated with the
4336 -- interface is the primary DT.
4338 and then not Is_Ancestor (Iface, Typ,
4339 Use_Full_View => True)
4340 then
4341 if not Build_Thunks then
4342 Prim_Pos :=
4343 UI_To_Int (DT_Position (Interface_Alias (Prim)));
4344 Prim_Table (Prim_Pos) := Alias (Prim);
4346 else
4347 Expand_Interface_Thunk (Prim, Thunk_Id, Thunk_Code);
4349 if Present (Thunk_Id) then
4350 Prim_Pos :=
4351 UI_To_Int (DT_Position (Interface_Alias (Prim)));
4353 Prim_Table (Prim_Pos) := Thunk_Id;
4354 Append_To (Result, Thunk_Code);
4355 end if;
4356 end if;
4357 end if;
4359 Next_Elmt (Prim_Elmt);
4360 end loop;
4362 for J in Prim_Table'Range loop
4363 if Present (Prim_Table (J)) then
4364 New_Node :=
4365 Unchecked_Convert_To (RTE (RE_Prim_Ptr),
4366 Make_Attribute_Reference (Loc,
4367 Prefix => New_Occurrence_Of (Prim_Table (J), Loc),
4368 Attribute_Name => Name_Unrestricted_Access));
4370 else
4371 New_Node := Make_Null (Loc);
4372 end if;
4374 Append_To (Prim_Ops_Aggr_List, New_Node);
4375 end loop;
4376 end;
4377 end if;
4379 New_Node :=
4380 Make_Aggregate (Loc,
4381 Expressions => Prim_Ops_Aggr_List);
4383 Append_To (DT_Aggr_List, New_Node);
4385 -- Remember aggregates initializing dispatch tables
4387 Append_Elmt (New_Node, DT_Aggr);
4389 -- Note: Secondary dispatch tables are declared constant only if
4390 -- we can compute their offset field by means of the extra dummy
4391 -- object; otherwise they cannot be declared constant and the
4392 -- Offset_To_Top component is initialized by the IP routine.
4394 Append_To (Result,
4395 Make_Object_Declaration (Loc,
4396 Defining_Identifier => Iface_DT,
4397 Aliased_Present => True,
4398 Constant_Present => Present (Dummy_Object),
4400 Object_Definition =>
4401 Make_Subtype_Indication (Loc,
4402 Subtype_Mark => New_Occurrence_Of
4403 (RTE (RE_Dispatch_Table_Wrapper), Loc),
4404 Constraint => Make_Index_Or_Discriminant_Constraint (Loc,
4405 Constraints => DT_Constr_List)),
4407 Expression =>
4408 Make_Aggregate (Loc,
4409 Expressions => DT_Aggr_List)));
4411 Append_To (Result,
4412 Make_Attribute_Definition_Clause (Loc,
4413 Name => New_Occurrence_Of (Iface_DT, Loc),
4414 Chars => Name_Alignment,
4416 Expression =>
4417 Make_Attribute_Reference (Loc,
4418 Prefix =>
4419 New_Occurrence_Of (RTE (RE_Integer_Address), Loc),
4420 Attribute_Name => Name_Alignment)));
4422 if Exporting_Table then
4423 Export_DT (Typ, Iface_DT, Suffix_Index);
4425 -- Generate code to create the pointer to the dispatch table
4427 -- Iface_DT_Ptr : Tag := Tag!(DT.Prims_Ptr'Address);
4429 -- Note: This declaration is not added here if the table is exported
4430 -- because in such case Make_Tags has already added this declaration.
4432 else
4433 Append_To (Result,
4434 Make_Object_Declaration (Loc,
4435 Defining_Identifier => Iface_DT_Ptr,
4436 Constant_Present => True,
4438 Object_Definition =>
4439 New_Occurrence_Of (RTE (RE_Interface_Tag), Loc),
4441 Expression =>
4442 Unchecked_Convert_To (RTE (RE_Interface_Tag),
4443 Make_Attribute_Reference (Loc,
4444 Prefix =>
4445 Make_Selected_Component (Loc,
4446 Prefix => New_Occurrence_Of (Iface_DT, Loc),
4447 Selector_Name =>
4448 New_Occurrence_Of
4449 (RTE_Record_Component (RE_Prims_Ptr), Loc)),
4450 Attribute_Name => Name_Address))));
4451 end if;
4453 Append_To (Result,
4454 Make_Object_Declaration (Loc,
4455 Defining_Identifier => Predef_Prims_Ptr,
4456 Constant_Present => True,
4458 Object_Definition =>
4459 New_Occurrence_Of (RTE (RE_Address), Loc),
4461 Expression =>
4462 Make_Attribute_Reference (Loc,
4463 Prefix =>
4464 Make_Selected_Component (Loc,
4465 Prefix => New_Occurrence_Of (Iface_DT, Loc),
4466 Selector_Name =>
4467 New_Occurrence_Of
4468 (RTE_Record_Component (RE_Predef_Prims), Loc)),
4469 Attribute_Name => Name_Address)));
4471 -- Remember entities containing dispatch tables
4473 Append_Elmt (Predef_Prims, DT_Decl);
4474 Append_Elmt (Iface_DT, DT_Decl);
4475 end Make_Secondary_DT;
4477 -- Local variables
4479 Elab_Code : constant List_Id := New_List;
4480 Result : constant List_Id := New_List;
4481 Tname : constant Name_Id := Chars (Typ);
4483 -- When pragmas Discard_Names and No_Tagged_Streams simultaneously apply
4484 -- we initialize the Expanded_Name and the External_Tag of this tagged
4485 -- type with an empty string. This is useful to avoid exposing entity
4486 -- names at binary level. It can be done when both pragmas apply because
4487 -- (1) Discard_Names allows initializing Expanded_Name with an
4488 -- implementation defined value (Ada RM Section C.5 (7/2)).
4489 -- (2) External_Tag (combined with Internal_Tag) is used for object
4490 -- streaming and No_Tagged_Streams inhibits the generation of
4491 -- streams.
4493 Discard_Names : constant Boolean :=
4494 Present (No_Tagged_Streams_Pragma (Typ))
4495 and then (Global_Discard_Names
4496 or else Einfo.Discard_Names (Typ));
4498 -- The following name entries are used by Make_DT to generate a number
4499 -- of entities related to a tagged type. These entities may be generated
4500 -- in a scope other than that of the tagged type declaration, and if
4501 -- the entities for two tagged types with the same name happen to be
4502 -- generated in the same scope, we have to take care to use different
4503 -- names. This is achieved by means of a unique serial number appended
4504 -- to each generated entity name.
4506 Name_DT : constant Name_Id :=
4507 New_External_Name (Tname, 'T', Suffix_Index => -1);
4508 Name_Exname : constant Name_Id :=
4509 New_External_Name (Tname, 'E', Suffix_Index => -1);
4510 Name_HT_Link : constant Name_Id :=
4511 New_External_Name (Tname, 'H', Suffix_Index => -1);
4512 Name_Predef_Prims : constant Name_Id :=
4513 New_External_Name (Tname, 'R', Suffix_Index => -1);
4514 Name_SSD : constant Name_Id :=
4515 New_External_Name (Tname, 'S', Suffix_Index => -1);
4516 Name_TSD : constant Name_Id :=
4517 New_External_Name (Tname, 'B', Suffix_Index => -1);
4519 Saved_GM : constant Ghost_Mode_Type := Ghost_Mode;
4520 Saved_IGR : constant Node_Id := Ignored_Ghost_Region;
4521 -- Save the Ghost-related attributes to restore on exit
4523 AI : Elmt_Id;
4524 AI_Tag_Elmt : Elmt_Id;
4525 AI_Tag_Comp : Elmt_Id;
4526 DT : Entity_Id;
4527 DT_Aggr_List : List_Id;
4528 DT_Constr_List : List_Id;
4529 DT_Ptr : Entity_Id;
4530 Exname : Entity_Id;
4531 HT_Link : Entity_Id;
4532 ITable : Node_Id;
4533 I_Depth : Nat := 0;
4534 Iface_Table_Node : Node_Id;
4535 Name_ITable : Name_Id;
4536 Nb_Predef_Prims : Nat := 0;
4537 Nb_Prim : Nat := 0;
4538 New_Node : Node_Id;
4539 Num_Ifaces : Nat := 0;
4540 Parent_Typ : Entity_Id;
4541 Predef_Prims : Entity_Id;
4542 Prim : Entity_Id;
4543 Prim_Elmt : Elmt_Id;
4544 Prim_Ops_Aggr_List : List_Id;
4545 SSD : Entity_Id;
4546 Suffix_Index : Int;
4547 Typ_Comps : Elist_Id;
4548 Typ_Ifaces : Elist_Id;
4549 TSD : Entity_Id;
4550 TSD_Aggr_List : List_Id;
4551 TSD_Tags_List : List_Id;
4553 -- Start of processing for Make_DT
4555 begin
4556 pragma Assert (Is_Frozen (Typ));
4558 -- The tagged type being processed may be subject to pragma Ghost. Set
4559 -- the mode now to ensure that any nodes generated during dispatch table
4560 -- creation are properly marked as Ghost.
4562 Set_Ghost_Mode (Typ);
4564 -- Handle cases in which there is no need to build the dispatch table
4566 if Has_Dispatch_Table (Typ)
4567 or else No (Access_Disp_Table (Typ))
4568 or else Is_CPP_Class (Typ)
4569 then
4570 goto Leave;
4572 elsif No_Run_Time_Mode then
4573 Error_Msg_CRT ("tagged types", Typ);
4574 goto Leave;
4576 elsif not RTE_Available (RE_Tag) then
4577 Append_To (Result,
4578 Make_Object_Declaration (Loc,
4579 Defining_Identifier =>
4580 Node (First_Elmt (Access_Disp_Table (Typ))),
4581 Object_Definition => New_Occurrence_Of (RTE (RE_Tag), Loc),
4582 Constant_Present => True,
4583 Expression =>
4584 Unchecked_Convert_To (RTE (RE_Tag),
4585 New_Occurrence_Of (RTE (RE_Null_Address), Loc))));
4587 Analyze_List (Result, Suppress => All_Checks);
4588 Error_Msg_CRT ("tagged types", Typ);
4589 goto Leave;
4590 end if;
4592 -- Ensure that the value of Max_Predef_Prims defined in a-tags is
4593 -- correct. Valid values are 9 under configurable runtime or 15
4594 -- with full runtime.
4596 if RTE_Available (RE_Interface_Data) then
4597 if Max_Predef_Prims /= 15 then
4598 Error_Msg_N ("run-time library configuration error", Typ);
4599 goto Leave;
4600 end if;
4601 else
4602 if Max_Predef_Prims /= 9 then
4603 Error_Msg_N ("run-time library configuration error", Typ);
4604 Error_Msg_CRT ("tagged types", Typ);
4605 goto Leave;
4606 end if;
4607 end if;
4609 DT := Make_Defining_Identifier (Loc, Name_DT);
4610 Exname := Make_Defining_Identifier (Loc, Name_Exname);
4611 HT_Link := Make_Defining_Identifier (Loc, Name_HT_Link);
4612 Predef_Prims := Make_Defining_Identifier (Loc, Name_Predef_Prims);
4613 SSD := Make_Defining_Identifier (Loc, Name_SSD);
4614 TSD := Make_Defining_Identifier (Loc, Name_TSD);
4616 -- Initialize Parent_Typ handling private types
4618 Parent_Typ := Etype (Typ);
4620 if Present (Full_View (Parent_Typ)) then
4621 Parent_Typ := Full_View (Parent_Typ);
4622 end if;
4624 -- Ensure that all the primitives are frozen. This is only required when
4625 -- building static dispatch tables --- the primitives must be frozen to
4626 -- be referenced (otherwise we have problems with the backend). It is
4627 -- not a requirement with nonstatic dispatch tables because in this case
4628 -- we generate now an empty dispatch table; the extra code required to
4629 -- register the primitives in the slots will be generated later --- when
4630 -- each primitive is frozen (see Freeze_Subprogram).
4632 if Building_Static_DT (Typ) then
4633 declare
4634 Saved_FLLTT : constant Boolean :=
4635 Freezing_Library_Level_Tagged_Type;
4637 Formal : Entity_Id;
4638 Frnodes : List_Id;
4639 Prim : Entity_Id;
4640 Prim_Elmt : Elmt_Id;
4642 begin
4643 Freezing_Library_Level_Tagged_Type := True;
4645 Prim_Elmt := First_Elmt (Primitive_Operations (Typ));
4646 while Present (Prim_Elmt) loop
4647 Prim := Node (Prim_Elmt);
4648 Frnodes := Freeze_Entity (Prim, Typ);
4650 -- We disable this check for abstract subprograms, given that
4651 -- they cannot be called directly and thus the state of their
4652 -- untagged formals is of no concern. The RM is unclear in any
4653 -- case concerning the need for this check, and this topic may
4654 -- go back to the ARG.
4656 if not Is_Abstract_Subprogram (Prim) then
4657 Formal := First_Formal (Prim);
4658 while Present (Formal) loop
4659 Check_Premature_Freezing (Prim, Typ, Etype (Formal));
4660 Next_Formal (Formal);
4661 end loop;
4663 Check_Premature_Freezing (Prim, Typ, Etype (Prim));
4664 end if;
4666 if Present (Frnodes) then
4667 Append_List_To (Result, Frnodes);
4668 end if;
4670 Next_Elmt (Prim_Elmt);
4671 end loop;
4673 Freezing_Library_Level_Tagged_Type := Saved_FLLTT;
4674 end;
4675 end if;
4677 if Building_Static_Secondary_DT (Typ) then
4678 declare
4679 Cannot_Have_Null_Disc : Boolean := False;
4680 Name_Dummy_Object : constant Name_Id :=
4681 New_External_Name (Tname,
4682 'P', Suffix_Index => -1);
4683 begin
4684 Dummy_Object := Make_Defining_Identifier (Loc, Name_Dummy_Object);
4686 -- Define the extra object imported and constant to avoid linker
4687 -- errors (since this object is never declared). Required because
4688 -- we implement RM 13.3(19) for exported and imported (variable)
4689 -- objects by making them volatile.
4691 Set_Is_Imported (Dummy_Object);
4692 Set_Ekind (Dummy_Object, E_Constant);
4693 Set_Is_True_Constant (Dummy_Object);
4694 Set_Related_Type (Dummy_Object, Typ);
4696 -- The scope must be set now to call Get_External_Name
4698 Set_Scope (Dummy_Object, Current_Scope);
4700 Get_External_Name (Dummy_Object);
4701 Set_Interface_Name (Dummy_Object,
4702 Make_String_Literal (Loc, Strval => String_From_Name_Buffer));
4704 -- Ensure proper Sprint output of this implicit importation
4706 Set_Is_Internal (Dummy_Object);
4708 if not Has_Discriminants (Typ) then
4709 Append_To (Result,
4710 Make_Object_Declaration (Loc,
4711 Defining_Identifier => Dummy_Object,
4712 Constant_Present => True,
4713 Object_Definition => New_Occurrence_Of (Typ, Loc)));
4714 else
4715 declare
4716 Constr_List : constant List_Id := New_List;
4717 Discrim : Node_Id;
4719 begin
4720 Discrim := First_Discriminant (Typ);
4721 while Present (Discrim) loop
4722 if Is_Discrete_Type (Etype (Discrim)) then
4723 Append_To (Constr_List,
4724 Make_Attribute_Reference (Loc,
4725 Prefix =>
4726 New_Occurrence_Of (Etype (Discrim), Loc),
4727 Attribute_Name => Name_First));
4729 else
4730 pragma Assert (Is_Access_Type (Etype (Discrim)));
4731 Cannot_Have_Null_Disc :=
4732 Cannot_Have_Null_Disc
4733 or else Can_Never_Be_Null (Etype (Discrim));
4734 Append_To (Constr_List, Make_Null (Loc));
4735 end if;
4737 Next_Discriminant (Discrim);
4738 end loop;
4740 Append_To (Result,
4741 Make_Object_Declaration (Loc,
4742 Defining_Identifier => Dummy_Object,
4743 Constant_Present => True,
4744 Object_Definition =>
4745 Make_Subtype_Indication (Loc,
4746 Subtype_Mark => New_Occurrence_Of (Typ, Loc),
4747 Constraint =>
4748 Make_Index_Or_Discriminant_Constraint (Loc,
4749 Constraints => Constr_List))));
4750 end;
4751 end if;
4753 -- Given that the dummy object will not be declared at run time,
4754 -- analyze its declaration with expansion disabled and warnings
4755 -- and error messages ignored.
4757 Expander_Mode_Save_And_Set (False);
4758 Ignore_Errors_Enable := Ignore_Errors_Enable + 1;
4759 Analyze (Last (Result), Suppress => All_Checks);
4760 Ignore_Errors_Enable := Ignore_Errors_Enable - 1;
4761 Expander_Mode_Restore;
4762 end;
4763 end if;
4765 -- Ada 2005 (AI-251): Build the secondary dispatch tables
4767 if Has_Interfaces (Typ) then
4768 Collect_Interface_Components (Typ, Typ_Comps);
4770 -- Each secondary dispatch table is assigned an unique positive
4771 -- suffix index; such value also corresponds with the location of
4772 -- its entity in the Dispatch_Table_Wrappers list (see Make_Tags).
4774 -- Note: This value must be kept sync with the Suffix_Index values
4775 -- generated by Make_Tags
4777 Suffix_Index := 1;
4778 AI_Tag_Elmt :=
4779 Next_Elmt (Next_Elmt (First_Elmt (Access_Disp_Table (Typ))));
4781 AI_Tag_Comp := First_Elmt (Typ_Comps);
4782 while Present (AI_Tag_Comp) loop
4783 pragma Assert (Has_Suffix (Node (AI_Tag_Elmt), 'P'));
4785 -- Build the secondary table containing pointers to thunks
4787 Make_Secondary_DT
4788 (Typ => Typ,
4789 Iface =>
4790 Base_Type (Related_Type (Node (AI_Tag_Comp))),
4791 Iface_Comp => Node (AI_Tag_Comp),
4792 Suffix_Index => Suffix_Index,
4793 Num_Iface_Prims =>
4794 UI_To_Int (DT_Entry_Count (Node (AI_Tag_Comp))),
4795 Iface_DT_Ptr => Node (AI_Tag_Elmt),
4796 Predef_Prims_Ptr => Node (Next_Elmt (AI_Tag_Elmt)),
4797 Build_Thunks => True,
4798 Result => Result);
4800 -- Skip secondary dispatch table referencing thunks to predefined
4801 -- primitives.
4803 Next_Elmt (AI_Tag_Elmt);
4804 pragma Assert (Has_Suffix (Node (AI_Tag_Elmt), 'Y'));
4806 -- Secondary dispatch table referencing user-defined primitives
4807 -- covered by this interface.
4809 Next_Elmt (AI_Tag_Elmt);
4810 pragma Assert (Has_Suffix (Node (AI_Tag_Elmt), 'D'));
4812 -- Build the secondary table containing pointers to primitives
4813 -- (used to give support to Generic Dispatching Constructors).
4815 Make_Secondary_DT
4816 (Typ => Typ,
4817 Iface => Base_Type
4818 (Related_Type (Node (AI_Tag_Comp))),
4819 Iface_Comp => Node (AI_Tag_Comp),
4820 Suffix_Index => -1,
4821 Num_Iface_Prims => UI_To_Int
4822 (DT_Entry_Count (Node (AI_Tag_Comp))),
4823 Iface_DT_Ptr => Node (AI_Tag_Elmt),
4824 Predef_Prims_Ptr => Node (Next_Elmt (AI_Tag_Elmt)),
4825 Build_Thunks => False,
4826 Result => Result);
4828 -- Skip secondary dispatch table referencing predefined primitives
4830 Next_Elmt (AI_Tag_Elmt);
4831 pragma Assert (Has_Suffix (Node (AI_Tag_Elmt), 'Z'));
4833 Suffix_Index := Suffix_Index + 1;
4834 Next_Elmt (AI_Tag_Elmt);
4835 Next_Elmt (AI_Tag_Comp);
4836 end loop;
4837 end if;
4839 -- Get the _tag entity and number of primitives of its dispatch table
4841 DT_Ptr := Node (First_Elmt (Access_Disp_Table (Typ)));
4842 Nb_Prim := UI_To_Int (DT_Entry_Count (First_Tag_Component (Typ)));
4844 if Generate_SCIL then
4845 Nb_Prim := 0;
4846 end if;
4848 Set_Is_Statically_Allocated (DT, Is_Library_Level_Tagged_Type (Typ));
4849 Set_Is_Statically_Allocated (SSD, Is_Library_Level_Tagged_Type (Typ));
4850 Set_Is_Statically_Allocated (TSD, Is_Library_Level_Tagged_Type (Typ));
4851 Set_Is_Statically_Allocated (Predef_Prims,
4852 Is_Library_Level_Tagged_Type (Typ));
4854 -- In case of locally defined tagged type we declare the object
4855 -- containing the dispatch table by means of a variable. Its
4856 -- initialization is done later by means of an assignment. This is
4857 -- required to generate its External_Tag.
4859 if not Building_Static_DT (Typ) then
4861 -- Generate:
4862 -- DT : No_Dispatch_Table_Wrapper;
4863 -- for DT'Alignment use Address'Alignment;
4864 -- DT_Ptr : Tag := !Tag (DT.NDT_Prims_Ptr'Address);
4866 if not Has_DT (Typ) then
4867 Append_To (Result,
4868 Make_Object_Declaration (Loc,
4869 Defining_Identifier => DT,
4870 Aliased_Present => True,
4871 Constant_Present => False,
4872 Object_Definition =>
4873 New_Occurrence_Of
4874 (RTE (RE_No_Dispatch_Table_Wrapper), Loc)));
4876 Append_To (Result,
4877 Make_Attribute_Definition_Clause (Loc,
4878 Name => New_Occurrence_Of (DT, Loc),
4879 Chars => Name_Alignment,
4880 Expression =>
4881 Make_Attribute_Reference (Loc,
4882 Prefix =>
4883 New_Occurrence_Of (RTE (RE_Integer_Address), Loc),
4884 Attribute_Name => Name_Alignment)));
4886 Append_To (Result,
4887 Make_Object_Declaration (Loc,
4888 Defining_Identifier => DT_Ptr,
4889 Object_Definition => New_Occurrence_Of (RTE (RE_Tag), Loc),
4890 Constant_Present => True,
4891 Expression =>
4892 Unchecked_Convert_To (RTE (RE_Tag),
4893 Make_Attribute_Reference (Loc,
4894 Prefix =>
4895 Make_Selected_Component (Loc,
4896 Prefix => New_Occurrence_Of (DT, Loc),
4897 Selector_Name =>
4898 New_Occurrence_Of
4899 (RTE_Record_Component (RE_NDT_Prims_Ptr), Loc)),
4900 Attribute_Name => Name_Address))));
4902 Set_Is_Statically_Allocated (DT_Ptr,
4903 Is_Library_Level_Tagged_Type (Typ));
4905 -- Generate the SCIL node for the previous object declaration
4906 -- because it has a tag initialization.
4908 if Generate_SCIL then
4909 New_Node :=
4910 Make_SCIL_Dispatch_Table_Tag_Init (Sloc (Last (Result)));
4911 Set_SCIL_Entity (New_Node, Typ);
4912 Set_SCIL_Node (Last (Result), New_Node);
4914 goto Leave_SCIL;
4916 -- Gnat2scil has its own implementation of dispatch tables,
4917 -- different than what is being implemented here. Generating
4918 -- further dispatch table initialization code would just
4919 -- cause gnat2scil to generate useless Scil which CodePeer
4920 -- would waste time and space analyzing, so we skip it.
4921 end if;
4923 -- Generate:
4924 -- DT : Dispatch_Table_Wrapper (Nb_Prim);
4925 -- for DT'Alignment use Address'Alignment;
4926 -- DT_Ptr : Tag := !Tag (DT.Prims_Ptr'Address);
4928 else
4929 -- If the tagged type has no primitives we add a dummy slot
4930 -- whose address will be the tag of this type.
4932 if Nb_Prim = 0 then
4933 DT_Constr_List :=
4934 New_List (Make_Integer_Literal (Loc, 1));
4935 else
4936 DT_Constr_List :=
4937 New_List (Make_Integer_Literal (Loc, Nb_Prim));
4938 end if;
4940 Append_To (Result,
4941 Make_Object_Declaration (Loc,
4942 Defining_Identifier => DT,
4943 Aliased_Present => True,
4944 Constant_Present => False,
4945 Object_Definition =>
4946 Make_Subtype_Indication (Loc,
4947 Subtype_Mark =>
4948 New_Occurrence_Of (RTE (RE_Dispatch_Table_Wrapper), Loc),
4949 Constraint =>
4950 Make_Index_Or_Discriminant_Constraint (Loc,
4951 Constraints => DT_Constr_List))));
4953 Append_To (Result,
4954 Make_Attribute_Definition_Clause (Loc,
4955 Name => New_Occurrence_Of (DT, Loc),
4956 Chars => Name_Alignment,
4957 Expression =>
4958 Make_Attribute_Reference (Loc,
4959 Prefix =>
4960 New_Occurrence_Of (RTE (RE_Integer_Address), Loc),
4961 Attribute_Name => Name_Alignment)));
4963 Append_To (Result,
4964 Make_Object_Declaration (Loc,
4965 Defining_Identifier => DT_Ptr,
4966 Object_Definition => New_Occurrence_Of (RTE (RE_Tag), Loc),
4967 Constant_Present => True,
4968 Expression =>
4969 Unchecked_Convert_To (RTE (RE_Tag),
4970 Make_Attribute_Reference (Loc,
4971 Prefix =>
4972 Make_Selected_Component (Loc,
4973 Prefix => New_Occurrence_Of (DT, Loc),
4974 Selector_Name =>
4975 New_Occurrence_Of
4976 (RTE_Record_Component (RE_Prims_Ptr), Loc)),
4977 Attribute_Name => Name_Address))));
4979 Set_Is_Statically_Allocated (DT_Ptr,
4980 Is_Library_Level_Tagged_Type (Typ));
4982 -- Generate the SCIL node for the previous object declaration
4983 -- because it has a tag initialization.
4985 if Generate_SCIL then
4986 New_Node :=
4987 Make_SCIL_Dispatch_Table_Tag_Init (Sloc (Last (Result)));
4988 Set_SCIL_Entity (New_Node, Typ);
4989 Set_SCIL_Node (Last (Result), New_Node);
4991 goto Leave_SCIL;
4993 -- Gnat2scil has its own implementation of dispatch tables,
4994 -- different than what is being implemented here. Generating
4995 -- further dispatch table initialization code would just
4996 -- cause gnat2scil to generate useless Scil which CodePeer
4997 -- would waste time and space analyzing, so we skip it.
4998 end if;
5000 Append_To (Result,
5001 Make_Object_Declaration (Loc,
5002 Defining_Identifier =>
5003 Node (Next_Elmt (First_Elmt (Access_Disp_Table (Typ)))),
5004 Constant_Present => True,
5005 Object_Definition =>
5006 New_Occurrence_Of (RTE (RE_Address), Loc),
5007 Expression =>
5008 Make_Attribute_Reference (Loc,
5009 Prefix =>
5010 Make_Selected_Component (Loc,
5011 Prefix => New_Occurrence_Of (DT, Loc),
5012 Selector_Name =>
5013 New_Occurrence_Of
5014 (RTE_Record_Component (RE_Predef_Prims), Loc)),
5015 Attribute_Name => Name_Address)));
5016 end if;
5017 end if;
5019 -- Generate: Expanded_Name : constant String := "";
5021 if Discard_Names then
5022 Append_To (Result,
5023 Make_Object_Declaration (Loc,
5024 Defining_Identifier => Exname,
5025 Constant_Present => True,
5026 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
5027 Expression =>
5028 Make_String_Literal (Loc, "")));
5030 -- Generate: Exname : constant String := full_qualified_name (typ);
5031 -- The type itself may be an anonymous parent type, so use the first
5032 -- subtype to have a user-recognizable name.
5034 else
5035 Append_To (Result,
5036 Make_Object_Declaration (Loc,
5037 Defining_Identifier => Exname,
5038 Constant_Present => True,
5039 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
5040 Expression =>
5041 Make_String_Literal (Loc,
5042 Fully_Qualified_Name_String (First_Subtype (Typ)))));
5043 end if;
5045 Set_Is_Statically_Allocated (Exname);
5046 Set_Is_True_Constant (Exname);
5048 -- Declare the object used by Ada.Tags.Register_Tag
5050 if RTE_Available (RE_Register_Tag) then
5051 Append_To (Result,
5052 Make_Object_Declaration (Loc,
5053 Defining_Identifier => HT_Link,
5054 Object_Definition => New_Occurrence_Of (RTE (RE_Tag), Loc),
5055 Expression => New_Occurrence_Of (RTE (RE_No_Tag), Loc)));
5056 end if;
5058 -- Generate code to create the storage for the type specific data object
5059 -- with enough space to store the tags of the ancestors plus the tags
5060 -- of all the implemented interfaces (as described in a-tags.adb).
5062 -- TSD : Type_Specific_Data (I_Depth) :=
5063 -- (Idepth => I_Depth,
5064 -- Access_Level => Type_Access_Level (Typ),
5065 -- Alignment => Typ'Alignment,
5066 -- Expanded_Name => Cstring_Ptr!(Exname'Address))
5067 -- External_Tag => Cstring_Ptr!(Exname'Address))
5068 -- HT_Link => HT_Link'Address,
5069 -- Transportable => <<boolean-value>>,
5070 -- Is_Abstract => <<boolean-value>>,
5071 -- Needs_Finalization => <<boolean-value>>,
5072 -- [ Size_Func => Size_Prim'Access, ]
5073 -- [ Interfaces_Table => <<access-value>>, ]
5074 -- [ SSD => SSD_Table'Address ]
5075 -- Tags_Table => (0 => null,
5076 -- 1 => Parent'Tag
5077 -- ...);
5078 -- for TSD'Alignment use Address'Alignment
5080 TSD_Aggr_List := New_List;
5082 -- Idepth: Count ancestors to compute the inheritance depth. For private
5083 -- extensions, always go to the full view in order to compute the real
5084 -- inheritance depth.
5086 declare
5087 Current_Typ : Entity_Id;
5088 Parent_Typ : Entity_Id;
5090 begin
5091 I_Depth := 0;
5092 Current_Typ := Typ;
5093 loop
5094 Parent_Typ := Etype (Current_Typ);
5096 if Is_Private_Type (Parent_Typ) then
5097 Parent_Typ := Full_View (Base_Type (Parent_Typ));
5098 end if;
5100 exit when Parent_Typ = Current_Typ;
5102 I_Depth := I_Depth + 1;
5103 Current_Typ := Parent_Typ;
5104 end loop;
5105 end;
5107 Append_To (TSD_Aggr_List,
5108 Make_Integer_Literal (Loc, I_Depth));
5110 -- Access_Level
5112 Append_To (TSD_Aggr_List,
5113 Make_Integer_Literal (Loc, Type_Access_Level (Typ)));
5115 -- Alignment
5117 -- For CPP types we cannot rely on the value of 'Alignment provided
5118 -- by the backend to initialize this TSD field.
5120 if Convention (Typ) = Convention_CPP
5121 or else Is_CPP_Class (Root_Type (Typ))
5122 then
5123 Append_To (TSD_Aggr_List,
5124 Make_Integer_Literal (Loc, 0));
5125 else
5126 Append_To (TSD_Aggr_List,
5127 Make_Attribute_Reference (Loc,
5128 Prefix => New_Occurrence_Of (Typ, Loc),
5129 Attribute_Name => Name_Alignment));
5130 end if;
5132 -- Expanded_Name
5134 Append_To (TSD_Aggr_List,
5135 Unchecked_Convert_To (RTE (RE_Cstring_Ptr),
5136 Make_Attribute_Reference (Loc,
5137 Prefix => New_Occurrence_Of (Exname, Loc),
5138 Attribute_Name => Name_Address)));
5140 -- External_Tag of a local tagged type
5142 -- <typ>A : constant String :=
5143 -- "Internal tag at 16#tag-addr#: <full-name-of-typ>";
5145 -- The reason we generate this strange name is that we do not want to
5146 -- enter local tagged types in the global hash table used to compute
5147 -- the Internal_Tag attribute for two reasons:
5149 -- 1. It is hard to avoid a tasking race condition for entering the
5150 -- entry into the hash table.
5152 -- 2. It would cause a storage leak, unless we rig up considerable
5153 -- mechanism to remove the entry from the hash table on exit.
5155 -- So what we do is to generate the above external tag name, where the
5156 -- hex address is the address of the local dispatch table (i.e. exactly
5157 -- the value we want if Internal_Tag is computed from this string).
5159 -- Of course this value will only be valid if the tagged type is still
5160 -- in scope, but it clearly must be erroneous to compute the internal
5161 -- tag of a tagged type that is out of scope.
5163 -- We don't do this processing if an explicit external tag has been
5164 -- specified. That's an odd case for which we have already issued a
5165 -- warning, where we will not be able to compute the internal tag.
5167 if not Discard_Names
5168 and then not Is_Library_Level_Entity (Typ)
5169 and then not Has_External_Tag_Rep_Clause (Typ)
5170 then
5171 declare
5172 Exname : constant Entity_Id :=
5173 Make_Defining_Identifier (Loc,
5174 Chars => New_External_Name (Tname, 'A'));
5175 Full_Name : constant String_Id :=
5176 Fully_Qualified_Name_String (First_Subtype (Typ));
5177 Str1_Id : String_Id;
5178 Str2_Id : String_Id;
5180 begin
5181 -- Generate:
5182 -- Str1 = "Internal tag at 16#";
5184 Start_String;
5185 Store_String_Chars ("Internal tag at 16#");
5186 Str1_Id := End_String;
5188 -- Generate:
5189 -- Str2 = "#: <type-full-name>";
5191 Start_String;
5192 Store_String_Chars ("#: ");
5193 Store_String_Chars (Full_Name);
5194 Str2_Id := End_String;
5196 -- Generate:
5197 -- Exname : constant String :=
5198 -- Str1 & Address_Image (Tag) & Str2;
5200 if RTE_Available (RE_Address_Image) then
5201 Append_To (Result,
5202 Make_Object_Declaration (Loc,
5203 Defining_Identifier => Exname,
5204 Constant_Present => True,
5205 Object_Definition => New_Occurrence_Of
5206 (Standard_String, Loc),
5207 Expression =>
5208 Make_Op_Concat (Loc,
5209 Left_Opnd => Make_String_Literal (Loc, Str1_Id),
5210 Right_Opnd =>
5211 Make_Op_Concat (Loc,
5212 Left_Opnd =>
5213 Make_Function_Call (Loc,
5214 Name =>
5215 New_Occurrence_Of
5216 (RTE (RE_Address_Image), Loc),
5217 Parameter_Associations => New_List (
5218 Unchecked_Convert_To (RTE (RE_Address),
5219 New_Occurrence_Of (DT_Ptr, Loc)))),
5220 Right_Opnd =>
5221 Make_String_Literal (Loc, Str2_Id)))));
5223 -- Generate:
5224 -- Exname : constant String := Str1 & Str2;
5226 else
5227 Append_To (Result,
5228 Make_Object_Declaration (Loc,
5229 Defining_Identifier => Exname,
5230 Constant_Present => True,
5231 Object_Definition =>
5232 New_Occurrence_Of (Standard_String, Loc),
5233 Expression =>
5234 Make_Op_Concat (Loc,
5235 Left_Opnd => Make_String_Literal (Loc, Str1_Id),
5236 Right_Opnd => Make_String_Literal (Loc, Str2_Id))));
5237 end if;
5239 New_Node :=
5240 Unchecked_Convert_To (RTE (RE_Cstring_Ptr),
5241 Make_Attribute_Reference (Loc,
5242 Prefix => New_Occurrence_Of (Exname, Loc),
5243 Attribute_Name => Name_Address));
5244 end;
5246 -- External tag of a library-level tagged type: Check for a definition
5247 -- of External_Tag. The clause is considered only if it applies to this
5248 -- specific tagged type, as opposed to one of its ancestors.
5249 -- If the type is an unconstrained type extension, we are building the
5250 -- dispatch table of its anonymous base type, so the external tag, if
5251 -- any was specified, must be retrieved from the first subtype. Go to
5252 -- the full view in case the clause is in the private part.
5254 else
5255 declare
5256 Def : constant Node_Id := Get_Attribute_Definition_Clause
5257 (Underlying_Type (First_Subtype (Typ)),
5258 Attribute_External_Tag);
5260 Old_Val : String_Id;
5261 New_Val : String_Id;
5262 E : Entity_Id;
5264 begin
5265 if not Present (Def)
5266 or else Entity (Name (Def)) /= First_Subtype (Typ)
5267 then
5268 New_Node :=
5269 Unchecked_Convert_To (RTE (RE_Cstring_Ptr),
5270 Make_Attribute_Reference (Loc,
5271 Prefix => New_Occurrence_Of (Exname, Loc),
5272 Attribute_Name => Name_Address));
5273 else
5274 Old_Val := Strval (Expr_Value_S (Expression (Def)));
5276 -- For the rep clause "for <typ>'external_tag use y" generate:
5278 -- <typ>A : constant string := y;
5280 -- <typ>A'Address is used to set the External_Tag component
5281 -- of the TSD
5283 -- Create a new nul terminated string if it is not already
5285 if String_Length (Old_Val) > 0
5286 and then
5287 Get_String_Char (Old_Val, String_Length (Old_Val)) = 0
5288 then
5289 New_Val := Old_Val;
5290 else
5291 Start_String (Old_Val);
5292 Store_String_Char (Get_Char_Code (ASCII.NUL));
5293 New_Val := End_String;
5294 end if;
5296 E := Make_Defining_Identifier (Loc,
5297 New_External_Name (Chars (Typ), 'A'));
5299 Append_To (Result,
5300 Make_Object_Declaration (Loc,
5301 Defining_Identifier => E,
5302 Constant_Present => True,
5303 Object_Definition =>
5304 New_Occurrence_Of (Standard_String, Loc),
5305 Expression =>
5306 Make_String_Literal (Loc, New_Val)));
5308 New_Node :=
5309 Unchecked_Convert_To (RTE (RE_Cstring_Ptr),
5310 Make_Attribute_Reference (Loc,
5311 Prefix => New_Occurrence_Of (E, Loc),
5312 Attribute_Name => Name_Address));
5313 end if;
5314 end;
5315 end if;
5317 Append_To (TSD_Aggr_List, New_Node);
5319 -- HT_Link
5321 if RTE_Available (RE_Register_Tag) then
5322 Append_To (TSD_Aggr_List,
5323 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
5324 Make_Attribute_Reference (Loc,
5325 Prefix => New_Occurrence_Of (HT_Link, Loc),
5326 Attribute_Name => Name_Address)));
5328 elsif RTE_Record_Component_Available (RE_HT_Link) then
5329 Append_To (TSD_Aggr_List,
5330 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
5331 New_Occurrence_Of (RTE (RE_Null_Address), Loc)));
5332 end if;
5334 -- Transportable: Set for types that can be used in remote calls
5335 -- with respect to E.4(18) legality rules.
5337 declare
5338 Transportable : Entity_Id;
5340 begin
5341 Transportable :=
5342 Boolean_Literals
5343 (Is_Pure (Typ)
5344 or else Is_Shared_Passive (Typ)
5345 or else
5346 ((Is_Remote_Types (Typ)
5347 or else Is_Remote_Call_Interface (Typ))
5348 and then Original_View_In_Visible_Part (Typ))
5349 or else not Comes_From_Source (Typ));
5351 Append_To (TSD_Aggr_List,
5352 New_Occurrence_Of (Transportable, Loc));
5353 end;
5355 -- Is_Abstract (Ada 2012: AI05-0173). This functionality is not
5356 -- available in the HIE runtime.
5358 if RTE_Record_Component_Available (RE_Is_Abstract) then
5359 declare
5360 Is_Abstract : Entity_Id;
5361 begin
5362 Is_Abstract := Boolean_Literals (Is_Abstract_Type (Typ));
5363 Append_To (TSD_Aggr_List,
5364 New_Occurrence_Of (Is_Abstract, Loc));
5365 end;
5366 end if;
5368 -- Needs_Finalization: Set if the type is controlled or has controlled
5369 -- components.
5371 declare
5372 Needs_Fin : Entity_Id;
5373 begin
5374 Needs_Fin := Boolean_Literals (Needs_Finalization (Typ));
5375 Append_To (TSD_Aggr_List, New_Occurrence_Of (Needs_Fin, Loc));
5376 end;
5378 -- Size_Func
5380 if RTE_Record_Component_Available (RE_Size_Func) then
5382 -- Initialize this field to Null_Address if we are not building
5383 -- static dispatch tables static or if the size function is not
5384 -- available. In the former case we cannot initialize this field
5385 -- until the function is frozen and registered in the dispatch
5386 -- table (see Register_Primitive).
5388 if not Building_Static_DT (Typ) or else not Has_DT (Typ) then
5389 Append_To (TSD_Aggr_List,
5390 Unchecked_Convert_To (RTE (RE_Size_Ptr),
5391 New_Occurrence_Of (RTE (RE_Null_Address), Loc)));
5393 else
5394 declare
5395 Prim_Elmt : Elmt_Id;
5396 Prim : Entity_Id;
5397 Size_Comp : Node_Id := Empty;
5399 begin
5400 Prim_Elmt := First_Elmt (Primitive_Operations (Typ));
5401 while Present (Prim_Elmt) loop
5402 Prim := Node (Prim_Elmt);
5404 if Chars (Prim) = Name_uSize then
5405 Prim := Ultimate_Alias (Prim);
5407 if Is_Abstract_Subprogram (Prim) then
5408 Size_Comp :=
5409 Unchecked_Convert_To (RTE (RE_Size_Ptr),
5410 New_Occurrence_Of (RTE (RE_Null_Address), Loc));
5411 else
5412 Size_Comp :=
5413 Unchecked_Convert_To (RTE (RE_Size_Ptr),
5414 Make_Attribute_Reference (Loc,
5415 Prefix => New_Occurrence_Of (Prim, Loc),
5416 Attribute_Name => Name_Unrestricted_Access));
5417 end if;
5419 exit;
5420 end if;
5422 Next_Elmt (Prim_Elmt);
5423 end loop;
5425 pragma Assert (Present (Size_Comp));
5426 Append_To (TSD_Aggr_List, Size_Comp);
5427 end;
5428 end if;
5429 end if;
5431 -- Interfaces_Table (required for AI-405)
5433 if RTE_Record_Component_Available (RE_Interfaces_Table) then
5435 -- Count the number of interface types implemented by Typ
5437 Collect_Interfaces (Typ, Typ_Ifaces);
5439 AI := First_Elmt (Typ_Ifaces);
5440 while Present (AI) loop
5441 Num_Ifaces := Num_Ifaces + 1;
5442 Next_Elmt (AI);
5443 end loop;
5445 if Num_Ifaces = 0 then
5446 Iface_Table_Node := Make_Null (Loc);
5448 -- Generate the Interface_Table object
5450 else
5451 declare
5452 TSD_Ifaces_List : constant List_Id := New_List;
5453 Elmt : Elmt_Id;
5454 Ifaces_List : Elist_Id := No_Elist;
5455 Ifaces_Comp_List : Elist_Id := No_Elist;
5456 Ifaces_Tag_List : Elist_Id;
5457 Offset_To_Top : Node_Id;
5458 Sec_DT_Tag : Node_Id;
5460 begin
5461 -- Collect interfaces information if we need to compute the
5462 -- offset to the top using the dummy object.
5464 if Present (Dummy_Object) then
5465 Collect_Interfaces_Info (Typ,
5466 Ifaces_List, Ifaces_Comp_List, Ifaces_Tag_List);
5467 end if;
5469 AI := First_Elmt (Typ_Ifaces);
5470 while Present (AI) loop
5471 if Is_Ancestor (Node (AI), Typ, Use_Full_View => True) then
5472 Sec_DT_Tag := New_Occurrence_Of (DT_Ptr, Loc);
5474 else
5475 Elmt :=
5476 Next_Elmt
5477 (Next_Elmt (First_Elmt (Access_Disp_Table (Typ))));
5478 pragma Assert (Has_Thunks (Node (Elmt)));
5480 while Is_Tag (Node (Elmt))
5481 and then not
5482 Is_Ancestor (Node (AI), Related_Type (Node (Elmt)),
5483 Use_Full_View => True)
5484 loop
5485 pragma Assert (Has_Thunks (Node (Elmt)));
5486 Next_Elmt (Elmt);
5487 pragma Assert (Has_Thunks (Node (Elmt)));
5488 Next_Elmt (Elmt);
5489 pragma Assert (not Has_Thunks (Node (Elmt)));
5490 Next_Elmt (Elmt);
5491 pragma Assert (not Has_Thunks (Node (Elmt)));
5492 Next_Elmt (Elmt);
5493 end loop;
5495 pragma Assert (Ekind (Node (Elmt)) = E_Constant
5496 and then not
5497 Has_Thunks (Node (Next_Elmt (Next_Elmt (Elmt)))));
5499 Sec_DT_Tag :=
5500 New_Occurrence_Of
5501 (Node (Next_Elmt (Next_Elmt (Elmt))), Loc);
5502 end if;
5504 -- For static dispatch tables compute Offset_To_Top using
5505 -- the dummy object.
5507 if Present (Dummy_Object) then
5508 declare
5509 Iface : constant Node_Id := Node (AI);
5510 Iface_Comp : Node_Id := Empty;
5511 Iface_Comp_Elmt : Elmt_Id;
5512 Iface_Elmt : Elmt_Id;
5514 begin
5515 Iface_Elmt := First_Elmt (Ifaces_List);
5516 Iface_Comp_Elmt := First_Elmt (Ifaces_Comp_List);
5518 while Present (Iface_Elmt) loop
5519 if Node (Iface_Elmt) = Iface then
5520 Iface_Comp := Node (Iface_Comp_Elmt);
5521 exit;
5522 end if;
5524 Next_Elmt (Iface_Elmt);
5525 Next_Elmt (Iface_Comp_Elmt);
5526 end loop;
5528 pragma Assert (Present (Iface_Comp));
5530 Offset_To_Top :=
5531 Make_Op_Minus (Loc,
5532 Make_Attribute_Reference (Loc,
5533 Prefix =>
5534 Make_Selected_Component (Loc,
5535 Prefix =>
5536 New_Occurrence_Of (Dummy_Object, Loc),
5537 Selector_Name =>
5538 New_Occurrence_Of (Iface_Comp, Loc)),
5539 Attribute_Name => Name_Position));
5540 end;
5541 else
5542 Offset_To_Top := Make_Integer_Literal (Loc, 0);
5543 end if;
5545 Append_To (TSD_Ifaces_List,
5546 Make_Aggregate (Loc,
5547 Expressions => New_List (
5549 -- Iface_Tag
5551 Unchecked_Convert_To (RTE (RE_Tag),
5552 New_Occurrence_Of
5553 (Node (First_Elmt (Access_Disp_Table (Node (AI)))),
5554 Loc)),
5556 -- Static_Offset_To_Top
5558 New_Occurrence_Of (Standard_True, Loc),
5560 -- Offset_To_Top_Value
5562 Offset_To_Top,
5564 -- Offset_To_Top_Func
5566 Make_Null (Loc),
5568 -- Secondary_DT
5570 Unchecked_Convert_To (RTE (RE_Tag), Sec_DT_Tag))));
5572 Next_Elmt (AI);
5573 end loop;
5575 Name_ITable := New_External_Name (Tname, 'I');
5576 ITable := Make_Defining_Identifier (Loc, Name_ITable);
5577 Set_Is_Statically_Allocated (ITable,
5578 Is_Library_Level_Tagged_Type (Typ));
5580 -- The table of interfaces is constant if we are building a
5581 -- static dispatch table; otherwise is not constant because
5582 -- its slots are filled at run time by the IP routine.
5584 Append_To (Result,
5585 Make_Object_Declaration (Loc,
5586 Defining_Identifier => ITable,
5587 Aliased_Present => True,
5588 Constant_Present => Present (Dummy_Object),
5589 Object_Definition =>
5590 Make_Subtype_Indication (Loc,
5591 Subtype_Mark =>
5592 New_Occurrence_Of (RTE (RE_Interface_Data), Loc),
5593 Constraint =>
5594 Make_Index_Or_Discriminant_Constraint (Loc,
5595 Constraints => New_List (
5596 Make_Integer_Literal (Loc, Num_Ifaces)))),
5598 Expression =>
5599 Make_Aggregate (Loc,
5600 Expressions => New_List (
5601 Make_Integer_Literal (Loc, Num_Ifaces),
5602 Make_Aggregate (Loc, TSD_Ifaces_List)))));
5604 Append_To (Result,
5605 Make_Attribute_Definition_Clause (Loc,
5606 Name => New_Occurrence_Of (ITable, Loc),
5607 Chars => Name_Alignment,
5608 Expression =>
5609 Make_Attribute_Reference (Loc,
5610 Prefix =>
5611 New_Occurrence_Of (RTE (RE_Integer_Address), Loc),
5612 Attribute_Name => Name_Alignment)));
5614 Iface_Table_Node :=
5615 Make_Attribute_Reference (Loc,
5616 Prefix => New_Occurrence_Of (ITable, Loc),
5617 Attribute_Name => Name_Unchecked_Access);
5618 end;
5619 end if;
5621 Append_To (TSD_Aggr_List, Iface_Table_Node);
5622 end if;
5624 -- Generate the Select Specific Data table for synchronized types that
5625 -- implement synchronized interfaces. The size of the table is
5626 -- constrained by the number of non-predefined primitive operations.
5628 if RTE_Record_Component_Available (RE_SSD) then
5629 if Ada_Version >= Ada_2005
5630 and then Has_DT (Typ)
5631 and then Is_Concurrent_Record_Type (Typ)
5632 and then Has_Interfaces (Typ)
5633 and then Nb_Prim > 0
5634 and then not Is_Abstract_Type (Typ)
5635 and then not Is_Controlled (Typ)
5636 and then not Restriction_Active (No_Dispatching_Calls)
5637 and then not Restriction_Active (No_Select_Statements)
5638 then
5639 Append_To (Result,
5640 Make_Object_Declaration (Loc,
5641 Defining_Identifier => SSD,
5642 Aliased_Present => True,
5643 Object_Definition =>
5644 Make_Subtype_Indication (Loc,
5645 Subtype_Mark => New_Occurrence_Of (
5646 RTE (RE_Select_Specific_Data), Loc),
5647 Constraint =>
5648 Make_Index_Or_Discriminant_Constraint (Loc,
5649 Constraints => New_List (
5650 Make_Integer_Literal (Loc, Nb_Prim))))));
5652 Append_To (Result,
5653 Make_Attribute_Definition_Clause (Loc,
5654 Name => New_Occurrence_Of (SSD, Loc),
5655 Chars => Name_Alignment,
5656 Expression =>
5657 Make_Attribute_Reference (Loc,
5658 Prefix =>
5659 New_Occurrence_Of (RTE (RE_Integer_Address), Loc),
5660 Attribute_Name => Name_Alignment)));
5662 -- This table is initialized by Make_Select_Specific_Data_Table,
5663 -- which calls Set_Entry_Index and Set_Prim_Op_Kind.
5665 Append_To (TSD_Aggr_List,
5666 Make_Attribute_Reference (Loc,
5667 Prefix => New_Occurrence_Of (SSD, Loc),
5668 Attribute_Name => Name_Unchecked_Access));
5669 else
5670 Append_To (TSD_Aggr_List, Make_Null (Loc));
5671 end if;
5672 end if;
5674 -- Initialize the table of ancestor tags. In case of interface types
5675 -- this table is not needed.
5677 TSD_Tags_List := New_List;
5679 -- If we are not statically allocating the dispatch table then we must
5680 -- fill position 0 with null because we still have not generated the
5681 -- tag of Typ.
5683 if not Building_Static_DT (Typ)
5684 or else Is_Interface (Typ)
5685 then
5686 Append_To (TSD_Tags_List,
5687 Unchecked_Convert_To (RTE (RE_Tag),
5688 New_Occurrence_Of (RTE (RE_Null_Address), Loc)));
5690 -- Otherwise we can safely reference the tag
5692 else
5693 Append_To (TSD_Tags_List,
5694 New_Occurrence_Of (DT_Ptr, Loc));
5695 end if;
5697 -- Fill the rest of the table with the tags of the ancestors
5699 declare
5700 Current_Typ : Entity_Id;
5701 Parent_Typ : Entity_Id;
5702 Pos : Nat;
5704 begin
5705 Pos := 1;
5706 Current_Typ := Typ;
5708 loop
5709 Parent_Typ := Etype (Current_Typ);
5711 if Is_Private_Type (Parent_Typ) then
5712 Parent_Typ := Full_View (Base_Type (Parent_Typ));
5713 end if;
5715 exit when Parent_Typ = Current_Typ;
5717 if Is_CPP_Class (Parent_Typ) then
5719 -- The tags defined in the C++ side will be inherited when
5720 -- the object is constructed (Exp_Ch3.Build_Init_Procedure)
5722 Append_To (TSD_Tags_List,
5723 Unchecked_Convert_To (RTE (RE_Tag),
5724 New_Occurrence_Of (RTE (RE_Null_Address), Loc)));
5725 else
5726 Append_To (TSD_Tags_List,
5727 New_Occurrence_Of
5728 (Node (First_Elmt (Access_Disp_Table (Parent_Typ))),
5729 Loc));
5730 end if;
5732 Pos := Pos + 1;
5733 Current_Typ := Parent_Typ;
5734 end loop;
5736 pragma Assert (Pos = I_Depth + 1);
5737 end;
5739 Append_To (TSD_Aggr_List,
5740 Make_Aggregate (Loc,
5741 Expressions => TSD_Tags_List));
5743 -- Build the TSD object
5745 Append_To (Result,
5746 Make_Object_Declaration (Loc,
5747 Defining_Identifier => TSD,
5748 Aliased_Present => True,
5749 Constant_Present => Building_Static_DT (Typ),
5750 Object_Definition =>
5751 Make_Subtype_Indication (Loc,
5752 Subtype_Mark => New_Occurrence_Of (
5753 RTE (RE_Type_Specific_Data), Loc),
5754 Constraint =>
5755 Make_Index_Or_Discriminant_Constraint (Loc,
5756 Constraints => New_List (
5757 Make_Integer_Literal (Loc, I_Depth)))),
5759 Expression => Make_Aggregate (Loc,
5760 Expressions => TSD_Aggr_List)));
5762 Set_Is_True_Constant (TSD, Building_Static_DT (Typ));
5764 Append_To (Result,
5765 Make_Attribute_Definition_Clause (Loc,
5766 Name => New_Occurrence_Of (TSD, Loc),
5767 Chars => Name_Alignment,
5768 Expression =>
5769 Make_Attribute_Reference (Loc,
5770 Prefix =>
5771 New_Occurrence_Of (RTE (RE_Integer_Address), Loc),
5772 Attribute_Name => Name_Alignment)));
5774 -- Initialize or declare the dispatch table object
5776 if not Has_DT (Typ) then
5777 DT_Constr_List := New_List;
5778 DT_Aggr_List := New_List;
5780 -- Typeinfo
5782 New_Node :=
5783 Make_Attribute_Reference (Loc,
5784 Prefix => New_Occurrence_Of (TSD, Loc),
5785 Attribute_Name => Name_Address);
5787 Append_To (DT_Constr_List, New_Node);
5788 Append_To (DT_Aggr_List, New_Copy (New_Node));
5789 Append_To (DT_Aggr_List, Make_Integer_Literal (Loc, 0));
5791 -- In case of locally defined tagged types we have already declared
5792 -- and uninitialized object for the dispatch table, which is now
5793 -- initialized by means of the following assignment:
5795 -- DT := (TSD'Address, 0);
5797 if not Building_Static_DT (Typ) then
5798 Append_To (Result,
5799 Make_Assignment_Statement (Loc,
5800 Name => New_Occurrence_Of (DT, Loc),
5801 Expression => Make_Aggregate (Loc, DT_Aggr_List)));
5803 -- In case of library level tagged types we declare and export now
5804 -- the constant object containing the dummy dispatch table. There
5805 -- is no need to declare the tag here because it has been previously
5806 -- declared by Make_Tags
5808 -- DT : aliased constant No_Dispatch_Table :=
5809 -- (NDT_TSD => TSD'Address;
5810 -- NDT_Prims_Ptr => 0);
5811 -- for DT'Alignment use Address'Alignment;
5813 else
5814 Append_To (Result,
5815 Make_Object_Declaration (Loc,
5816 Defining_Identifier => DT,
5817 Aliased_Present => True,
5818 Constant_Present => True,
5819 Object_Definition =>
5820 New_Occurrence_Of (RTE (RE_No_Dispatch_Table_Wrapper), Loc),
5821 Expression => Make_Aggregate (Loc, DT_Aggr_List)));
5823 Append_To (Result,
5824 Make_Attribute_Definition_Clause (Loc,
5825 Name => New_Occurrence_Of (DT, Loc),
5826 Chars => Name_Alignment,
5827 Expression =>
5828 Make_Attribute_Reference (Loc,
5829 Prefix =>
5830 New_Occurrence_Of (RTE (RE_Integer_Address), Loc),
5831 Attribute_Name => Name_Alignment)));
5833 Export_DT (Typ, DT);
5834 end if;
5836 -- Common case: Typ has a dispatch table
5838 -- Generate:
5840 -- Predef_Prims : Address_Array (1 .. Default_Prim_Ops_Count) :=
5841 -- (predef-prim-op-1'address,
5842 -- predef-prim-op-2'address,
5843 -- ...
5844 -- predef-prim-op-n'address);
5845 -- for Predef_Prims'Alignment use Address'Alignment
5847 -- DT : Dispatch_Table (Nb_Prims) :=
5848 -- (Signature => <sig-value>,
5849 -- Tag_Kind => <tag_kind-value>,
5850 -- Predef_Prims => Predef_Prims'First'Address,
5851 -- Offset_To_Top => 0,
5852 -- TSD => TSD'Address;
5853 -- Prims_Ptr => (prim-op-1'address,
5854 -- prim-op-2'address,
5855 -- ...
5856 -- prim-op-n'address));
5857 -- for DT'Alignment use Address'Alignment
5859 else
5860 declare
5861 Pos : Nat;
5863 begin
5864 if not Building_Static_DT (Typ) then
5865 Nb_Predef_Prims := Max_Predef_Prims;
5867 else
5868 Prim_Elmt := First_Elmt (Primitive_Operations (Typ));
5869 while Present (Prim_Elmt) loop
5870 Prim := Node (Prim_Elmt);
5872 if Is_Predefined_Dispatching_Operation (Prim)
5873 and then not Is_Abstract_Subprogram (Prim)
5874 then
5875 Pos := UI_To_Int (DT_Position (Prim));
5877 if Pos > Nb_Predef_Prims then
5878 Nb_Predef_Prims := Pos;
5879 end if;
5880 end if;
5882 Next_Elmt (Prim_Elmt);
5883 end loop;
5884 end if;
5886 declare
5887 Prim_Table : array
5888 (Nat range 1 .. Nb_Predef_Prims) of Entity_Id;
5889 Decl : Node_Id;
5890 E : Entity_Id;
5892 begin
5893 Prim_Ops_Aggr_List := New_List;
5895 Prim_Table := (others => Empty);
5897 if Building_Static_DT (Typ) then
5898 Prim_Elmt := First_Elmt (Primitive_Operations (Typ));
5899 while Present (Prim_Elmt) loop
5900 Prim := Node (Prim_Elmt);
5902 if Is_Predefined_Dispatching_Operation (Prim)
5903 and then not Is_Abstract_Subprogram (Prim)
5904 and then not Is_Eliminated (Prim)
5905 and then not Present (Prim_Table
5906 (UI_To_Int (DT_Position (Prim))))
5907 then
5908 E := Ultimate_Alias (Prim);
5909 pragma Assert (not Is_Abstract_Subprogram (E));
5910 Prim_Table (UI_To_Int (DT_Position (Prim))) := E;
5911 end if;
5913 Next_Elmt (Prim_Elmt);
5914 end loop;
5915 end if;
5917 for J in Prim_Table'Range loop
5918 if Present (Prim_Table (J)) then
5919 New_Node :=
5920 Unchecked_Convert_To (RTE (RE_Prim_Ptr),
5921 Make_Attribute_Reference (Loc,
5922 Prefix =>
5923 New_Occurrence_Of (Prim_Table (J), Loc),
5924 Attribute_Name => Name_Unrestricted_Access));
5925 else
5926 New_Node := Make_Null (Loc);
5927 end if;
5929 Append_To (Prim_Ops_Aggr_List, New_Node);
5930 end loop;
5932 New_Node :=
5933 Make_Aggregate (Loc,
5934 Expressions => Prim_Ops_Aggr_List);
5936 Decl :=
5937 Make_Subtype_Declaration (Loc,
5938 Defining_Identifier => Make_Temporary (Loc, 'S'),
5939 Subtype_Indication =>
5940 New_Occurrence_Of (RTE (RE_Address_Array), Loc));
5942 Append_To (Result, Decl);
5944 Append_To (Result,
5945 Make_Object_Declaration (Loc,
5946 Defining_Identifier => Predef_Prims,
5947 Aliased_Present => True,
5948 Constant_Present => Building_Static_DT (Typ),
5949 Object_Definition =>
5950 New_Occurrence_Of (Defining_Identifier (Decl), Loc),
5951 Expression => New_Node));
5953 -- Remember aggregates initializing dispatch tables
5955 Append_Elmt (New_Node, DT_Aggr);
5957 Append_To (Result,
5958 Make_Attribute_Definition_Clause (Loc,
5959 Name => New_Occurrence_Of (Predef_Prims, Loc),
5960 Chars => Name_Alignment,
5961 Expression =>
5962 Make_Attribute_Reference (Loc,
5963 Prefix =>
5964 New_Occurrence_Of (RTE (RE_Integer_Address), Loc),
5965 Attribute_Name => Name_Alignment)));
5966 end;
5967 end;
5969 -- Stage 1: Initialize the discriminant and the record components
5971 DT_Constr_List := New_List;
5972 DT_Aggr_List := New_List;
5974 -- Num_Prims. If the tagged type has no primitives we add a dummy
5975 -- slot whose address will be the tag of this type.
5977 if Nb_Prim = 0 then
5978 New_Node := Make_Integer_Literal (Loc, 1);
5979 else
5980 New_Node := Make_Integer_Literal (Loc, Nb_Prim);
5981 end if;
5983 Append_To (DT_Constr_List, New_Node);
5984 Append_To (DT_Aggr_List, New_Copy (New_Node));
5986 -- Signature
5988 if RTE_Record_Component_Available (RE_Signature) then
5989 Append_To (DT_Aggr_List,
5990 New_Occurrence_Of (RTE (RE_Primary_DT), Loc));
5991 end if;
5993 -- Tag_Kind
5995 if RTE_Record_Component_Available (RE_Tag_Kind) then
5996 Append_To (DT_Aggr_List, Tagged_Kind (Typ));
5997 end if;
5999 -- Predef_Prims
6001 Append_To (DT_Aggr_List,
6002 Make_Attribute_Reference (Loc,
6003 Prefix => New_Occurrence_Of (Predef_Prims, Loc),
6004 Attribute_Name => Name_Address));
6006 -- Offset_To_Top
6008 Append_To (DT_Aggr_List, Make_Integer_Literal (Loc, 0));
6010 -- Typeinfo
6012 Append_To (DT_Aggr_List,
6013 Make_Attribute_Reference (Loc,
6014 Prefix => New_Occurrence_Of (TSD, Loc),
6015 Attribute_Name => Name_Address));
6017 -- Stage 2: Initialize the table of user-defined primitive operations
6019 Prim_Ops_Aggr_List := New_List;
6021 if Nb_Prim = 0 then
6022 Append_To (Prim_Ops_Aggr_List, Make_Null (Loc));
6024 elsif not Building_Static_DT (Typ) then
6025 for J in 1 .. Nb_Prim loop
6026 Append_To (Prim_Ops_Aggr_List, Make_Null (Loc));
6027 end loop;
6029 else
6030 declare
6031 CPP_Nb_Prims : constant Nat := CPP_Num_Prims (Typ);
6032 E : Entity_Id;
6033 Prim : Entity_Id;
6034 Prim_Elmt : Elmt_Id;
6035 Prim_Pos : Nat;
6036 Prim_Table : array (Nat range 1 .. Nb_Prim) of Entity_Id;
6038 begin
6039 Prim_Table := (others => Empty);
6041 Prim_Elmt := First_Elmt (Primitive_Operations (Typ));
6042 while Present (Prim_Elmt) loop
6043 Prim := Node (Prim_Elmt);
6045 -- Retrieve the ultimate alias of the primitive for proper
6046 -- handling of renamings and eliminated primitives.
6048 E := Ultimate_Alias (Prim);
6050 -- If the alias is not a primitive operation then Prim does
6051 -- not rename another primitive, but rather an operation
6052 -- declared elsewhere (e.g. in another scope) and therefore
6053 -- Prim is a new primitive.
6055 if No (Find_Dispatching_Type (E)) then
6056 E := Prim;
6057 end if;
6059 Prim_Pos := UI_To_Int (DT_Position (E));
6061 -- Skip predefined primitives because they are located in a
6062 -- separate dispatch table.
6064 if not Is_Predefined_Dispatching_Operation (Prim)
6065 and then not Is_Predefined_Dispatching_Operation (E)
6067 -- Skip entities with attribute Interface_Alias because
6068 -- those are only required to build secondary dispatch
6069 -- tables.
6071 and then not Present (Interface_Alias (Prim))
6073 -- Skip abstract and eliminated primitives
6075 and then not Is_Abstract_Subprogram (E)
6076 and then not Is_Eliminated (E)
6078 -- For derivations of CPP types skip primitives located in
6079 -- the C++ part of the dispatch table because their slots
6080 -- are initialized by the IC routine.
6082 and then (not Is_CPP_Class (Root_Type (Typ))
6083 or else Prim_Pos > CPP_Nb_Prims)
6085 -- Skip ignored Ghost subprograms as those will be removed
6086 -- from the executable.
6088 and then not Is_Ignored_Ghost_Entity (E)
6089 then
6090 pragma Assert
6091 (UI_To_Int (DT_Position (Prim)) <= Nb_Prim);
6093 Prim_Table (UI_To_Int (DT_Position (Prim))) := E;
6094 end if;
6096 Next_Elmt (Prim_Elmt);
6097 end loop;
6099 for J in Prim_Table'Range loop
6100 if Present (Prim_Table (J)) then
6101 New_Node :=
6102 Unchecked_Convert_To (RTE (RE_Prim_Ptr),
6103 Make_Attribute_Reference (Loc,
6104 Prefix =>
6105 New_Occurrence_Of (Prim_Table (J), Loc),
6106 Attribute_Name => Name_Unrestricted_Access));
6107 else
6108 New_Node := Make_Null (Loc);
6109 end if;
6111 Append_To (Prim_Ops_Aggr_List, New_Node);
6112 end loop;
6113 end;
6114 end if;
6116 New_Node :=
6117 Make_Aggregate (Loc,
6118 Expressions => Prim_Ops_Aggr_List);
6120 Append_To (DT_Aggr_List, New_Node);
6122 -- Remember aggregates initializing dispatch tables
6124 Append_Elmt (New_Node, DT_Aggr);
6126 -- In case of locally defined tagged types we have already declared
6127 -- and uninitialized object for the dispatch table, which is now
6128 -- initialized by means of an assignment.
6130 if not Building_Static_DT (Typ) then
6131 Append_To (Result,
6132 Make_Assignment_Statement (Loc,
6133 Name => New_Occurrence_Of (DT, Loc),
6134 Expression => Make_Aggregate (Loc, DT_Aggr_List)));
6136 -- In case of library level tagged types we declare now and export
6137 -- the constant object containing the dispatch table.
6139 else
6140 Append_To (Result,
6141 Make_Object_Declaration (Loc,
6142 Defining_Identifier => DT,
6143 Aliased_Present => True,
6144 Constant_Present => True,
6145 Object_Definition =>
6146 Make_Subtype_Indication (Loc,
6147 Subtype_Mark => New_Occurrence_Of
6148 (RTE (RE_Dispatch_Table_Wrapper), Loc),
6149 Constraint => Make_Index_Or_Discriminant_Constraint (Loc,
6150 Constraints => DT_Constr_List)),
6151 Expression => Make_Aggregate (Loc, DT_Aggr_List)));
6153 Append_To (Result,
6154 Make_Attribute_Definition_Clause (Loc,
6155 Name => New_Occurrence_Of (DT, Loc),
6156 Chars => Name_Alignment,
6157 Expression =>
6158 Make_Attribute_Reference (Loc,
6159 Prefix =>
6160 New_Occurrence_Of (RTE (RE_Integer_Address), Loc),
6161 Attribute_Name => Name_Alignment)));
6163 Export_DT (Typ, DT);
6164 end if;
6165 end if;
6167 -- Initialize the table of ancestor tags if not building static
6168 -- dispatch table
6170 if not Building_Static_DT (Typ)
6171 and then not Is_Interface (Typ)
6172 and then not Is_CPP_Class (Typ)
6173 then
6174 Append_To (Result,
6175 Make_Assignment_Statement (Loc,
6176 Name =>
6177 Make_Indexed_Component (Loc,
6178 Prefix =>
6179 Make_Selected_Component (Loc,
6180 Prefix => New_Occurrence_Of (TSD, Loc),
6181 Selector_Name =>
6182 New_Occurrence_Of
6183 (RTE_Record_Component (RE_Tags_Table), Loc)),
6184 Expressions =>
6185 New_List (Make_Integer_Literal (Loc, 0))),
6187 Expression =>
6188 New_Occurrence_Of
6189 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc)));
6190 end if;
6192 -- Inherit the dispatch tables of the parent. There is no need to
6193 -- inherit anything from the parent when building static dispatch tables
6194 -- because the whole dispatch table (including inherited primitives) has
6195 -- been already built.
6197 if Building_Static_DT (Typ) then
6198 null;
6200 -- If the ancestor is a CPP_Class type we inherit the dispatch tables
6201 -- in the init proc, and we don't need to fill them in here.
6203 elsif Is_CPP_Class (Parent_Typ) then
6204 null;
6206 -- Otherwise we fill in the dispatch tables here
6208 else
6209 if Typ /= Parent_Typ
6210 and then not Is_Interface (Typ)
6211 and then not Restriction_Active (No_Dispatching_Calls)
6212 then
6213 -- Inherit the dispatch table
6215 if not Is_Interface (Typ)
6216 and then not Is_Interface (Parent_Typ)
6217 and then not Is_CPP_Class (Parent_Typ)
6218 then
6219 declare
6220 Nb_Prims : constant Int :=
6221 UI_To_Int (DT_Entry_Count
6222 (First_Tag_Component (Parent_Typ)));
6224 begin
6225 Append_To (Elab_Code,
6226 Build_Inherit_Predefined_Prims (Loc,
6227 Old_Tag_Node =>
6228 New_Occurrence_Of
6229 (Node
6230 (Next_Elmt
6231 (First_Elmt
6232 (Access_Disp_Table (Parent_Typ)))), Loc),
6233 New_Tag_Node =>
6234 New_Occurrence_Of
6235 (Node
6236 (Next_Elmt
6237 (First_Elmt
6238 (Access_Disp_Table (Typ)))), Loc)));
6240 if Nb_Prims /= 0 then
6241 Append_To (Elab_Code,
6242 Build_Inherit_Prims (Loc,
6243 Typ => Typ,
6244 Old_Tag_Node =>
6245 New_Occurrence_Of
6246 (Node
6247 (First_Elmt
6248 (Access_Disp_Table (Parent_Typ))), Loc),
6249 New_Tag_Node => New_Occurrence_Of (DT_Ptr, Loc),
6250 Num_Prims => Nb_Prims));
6251 end if;
6252 end;
6253 end if;
6255 -- Inherit the secondary dispatch tables of the ancestor
6257 if not Is_CPP_Class (Parent_Typ) then
6258 declare
6259 Sec_DT_Ancestor : Elmt_Id :=
6260 Next_Elmt
6261 (Next_Elmt
6262 (First_Elmt
6263 (Access_Disp_Table
6264 (Parent_Typ))));
6265 Sec_DT_Typ : Elmt_Id :=
6266 Next_Elmt
6267 (Next_Elmt
6268 (First_Elmt
6269 (Access_Disp_Table (Typ))));
6271 procedure Copy_Secondary_DTs (Typ : Entity_Id);
6272 -- Local procedure required to climb through the ancestors
6273 -- and copy the contents of all their secondary dispatch
6274 -- tables.
6276 ------------------------
6277 -- Copy_Secondary_DTs --
6278 ------------------------
6280 procedure Copy_Secondary_DTs (Typ : Entity_Id) is
6281 E : Entity_Id;
6282 Iface : Elmt_Id;
6284 begin
6285 -- Climb to the ancestor (if any) handling private types
6287 if Present (Full_View (Etype (Typ))) then
6288 if Full_View (Etype (Typ)) /= Typ then
6289 Copy_Secondary_DTs (Full_View (Etype (Typ)));
6290 end if;
6292 elsif Etype (Typ) /= Typ then
6293 Copy_Secondary_DTs (Etype (Typ));
6294 end if;
6296 if Present (Interfaces (Typ))
6297 and then not Is_Empty_Elmt_List (Interfaces (Typ))
6298 then
6299 Iface := First_Elmt (Interfaces (Typ));
6300 E := First_Entity (Typ);
6301 while Present (E)
6302 and then Present (Node (Sec_DT_Ancestor))
6303 and then Ekind (Node (Sec_DT_Ancestor)) = E_Constant
6304 loop
6305 if Is_Tag (E) and then Chars (E) /= Name_uTag then
6306 declare
6307 Num_Prims : constant Int :=
6308 UI_To_Int (DT_Entry_Count (E));
6310 begin
6311 if not Is_Interface (Etype (Typ)) then
6313 -- Inherit first secondary dispatch table
6315 Append_To (Elab_Code,
6316 Build_Inherit_Predefined_Prims (Loc,
6317 Old_Tag_Node =>
6318 Unchecked_Convert_To (RTE (RE_Tag),
6319 New_Occurrence_Of
6320 (Node
6321 (Next_Elmt (Sec_DT_Ancestor)),
6322 Loc)),
6323 New_Tag_Node =>
6324 Unchecked_Convert_To (RTE (RE_Tag),
6325 New_Occurrence_Of
6326 (Node (Next_Elmt (Sec_DT_Typ)),
6327 Loc))));
6329 if Num_Prims /= 0 then
6330 Append_To (Elab_Code,
6331 Build_Inherit_Prims (Loc,
6332 Typ => Node (Iface),
6333 Old_Tag_Node =>
6334 Unchecked_Convert_To
6335 (RTE (RE_Tag),
6336 New_Occurrence_Of
6337 (Node (Sec_DT_Ancestor),
6338 Loc)),
6339 New_Tag_Node =>
6340 Unchecked_Convert_To
6341 (RTE (RE_Tag),
6342 New_Occurrence_Of
6343 (Node (Sec_DT_Typ), Loc)),
6344 Num_Prims => Num_Prims));
6345 end if;
6346 end if;
6348 Next_Elmt (Sec_DT_Ancestor);
6349 Next_Elmt (Sec_DT_Typ);
6351 -- Skip the secondary dispatch table of
6352 -- predefined primitives
6354 Next_Elmt (Sec_DT_Ancestor);
6355 Next_Elmt (Sec_DT_Typ);
6357 if not Is_Interface (Etype (Typ)) then
6359 -- Inherit second secondary dispatch table
6361 Append_To (Elab_Code,
6362 Build_Inherit_Predefined_Prims (Loc,
6363 Old_Tag_Node =>
6364 Unchecked_Convert_To (RTE (RE_Tag),
6365 New_Occurrence_Of
6366 (Node
6367 (Next_Elmt (Sec_DT_Ancestor)),
6368 Loc)),
6369 New_Tag_Node =>
6370 Unchecked_Convert_To (RTE (RE_Tag),
6371 New_Occurrence_Of
6372 (Node (Next_Elmt (Sec_DT_Typ)),
6373 Loc))));
6375 if Num_Prims /= 0 then
6376 Append_To (Elab_Code,
6377 Build_Inherit_Prims (Loc,
6378 Typ => Node (Iface),
6379 Old_Tag_Node =>
6380 Unchecked_Convert_To
6381 (RTE (RE_Tag),
6382 New_Occurrence_Of
6383 (Node (Sec_DT_Ancestor),
6384 Loc)),
6385 New_Tag_Node =>
6386 Unchecked_Convert_To
6387 (RTE (RE_Tag),
6388 New_Occurrence_Of
6389 (Node (Sec_DT_Typ), Loc)),
6390 Num_Prims => Num_Prims));
6391 end if;
6392 end if;
6393 end;
6395 Next_Elmt (Sec_DT_Ancestor);
6396 Next_Elmt (Sec_DT_Typ);
6398 -- Skip the secondary dispatch table of
6399 -- predefined primitives
6401 Next_Elmt (Sec_DT_Ancestor);
6402 Next_Elmt (Sec_DT_Typ);
6404 Next_Elmt (Iface);
6405 end if;
6407 Next_Entity (E);
6408 end loop;
6409 end if;
6410 end Copy_Secondary_DTs;
6412 begin
6413 if Present (Node (Sec_DT_Ancestor))
6414 and then Ekind (Node (Sec_DT_Ancestor)) = E_Constant
6415 then
6416 -- Handle private types
6418 if Present (Full_View (Typ)) then
6419 Copy_Secondary_DTs (Full_View (Typ));
6420 else
6421 Copy_Secondary_DTs (Typ);
6422 end if;
6423 end if;
6424 end;
6425 end if;
6426 end if;
6427 end if;
6429 -- Generate code to check if the external tag of this type is the same
6430 -- as the external tag of some other declaration.
6432 -- Check_TSD (TSD'Unrestricted_Access);
6434 -- This check is a consequence of AI05-0113-1/06, so it officially
6435 -- applies to Ada 2005 (and Ada 2012). It might be argued that it is
6436 -- a desirable check to add in Ada 95 mode, but we hesitate to make
6437 -- this change, as it would be incompatible, and could conceivably
6438 -- cause a problem in existing Ada 95 code.
6440 -- We check for No_Run_Time_Mode here, because we do not want to pick
6441 -- up the RE_Check_TSD entity and call it in No_Run_Time mode.
6443 -- We cannot perform this check if the generation of its expanded name
6444 -- was discarded.
6446 if not No_Run_Time_Mode
6447 and then not Discard_Names
6448 and then Ada_Version >= Ada_2005
6449 and then RTE_Available (RE_Check_TSD)
6450 and then not Duplicated_Tag_Checks_Suppressed (Typ)
6451 then
6452 Append_To (Elab_Code,
6453 Make_Procedure_Call_Statement (Loc,
6454 Name =>
6455 New_Occurrence_Of (RTE (RE_Check_TSD), Loc),
6456 Parameter_Associations => New_List (
6457 Make_Attribute_Reference (Loc,
6458 Prefix => New_Occurrence_Of (TSD, Loc),
6459 Attribute_Name => Name_Unchecked_Access))));
6460 end if;
6462 -- Generate code to register the Tag in the External_Tag hash table for
6463 -- the pure Ada type only.
6465 -- Register_Tag (Dt_Ptr);
6467 -- Skip this action in the following cases:
6468 -- 1) if Register_Tag is not available.
6469 -- 2) in No_Run_Time mode.
6470 -- 3) if Typ is not defined at the library level (this is required
6471 -- to avoid adding concurrency control to the hash table used
6472 -- by the run-time to register the tags).
6474 if not No_Run_Time_Mode
6475 and then Is_Library_Level_Entity (Typ)
6476 and then RTE_Available (RE_Register_Tag)
6477 then
6478 Append_To (Elab_Code,
6479 Make_Procedure_Call_Statement (Loc,
6480 Name =>
6481 New_Occurrence_Of (RTE (RE_Register_Tag), Loc),
6482 Parameter_Associations =>
6483 New_List (New_Occurrence_Of (DT_Ptr, Loc))));
6484 end if;
6486 if not Is_Empty_List (Elab_Code) then
6487 Append_List_To (Result, Elab_Code);
6488 end if;
6490 -- Populate the two auxiliary tables used for dispatching asynchronous,
6491 -- conditional and timed selects for synchronized types that implement
6492 -- a limited interface. Skip this step in Ravenscar profile or when
6493 -- general dispatching is forbidden.
6495 if Ada_Version >= Ada_2005
6496 and then Is_Concurrent_Record_Type (Typ)
6497 and then Has_Interfaces (Typ)
6498 and then not Restriction_Active (No_Dispatching_Calls)
6499 and then not Restriction_Active (No_Select_Statements)
6500 then
6501 Append_List_To (Result,
6502 Make_Select_Specific_Data_Table (Typ));
6503 end if;
6505 -- Remember entities containing dispatch tables
6507 Append_Elmt (Predef_Prims, DT_Decl);
6508 Append_Elmt (DT, DT_Decl);
6510 Analyze_List (Result, Suppress => All_Checks);
6511 Set_Has_Dispatch_Table (Typ);
6513 -- Mark entities containing dispatch tables. Required by the backend to
6514 -- handle them properly.
6516 if Has_DT (Typ) then
6517 declare
6518 Elmt : Elmt_Id;
6520 begin
6521 -- Object declarations
6523 Elmt := First_Elmt (DT_Decl);
6524 while Present (Elmt) loop
6525 Set_Is_Dispatch_Table_Entity (Node (Elmt));
6526 pragma Assert (Ekind (Etype (Node (Elmt))) = E_Array_Subtype
6527 or else Ekind (Etype (Node (Elmt))) = E_Record_Subtype);
6528 Set_Is_Dispatch_Table_Entity (Etype (Node (Elmt)));
6529 Next_Elmt (Elmt);
6530 end loop;
6532 -- Aggregates initializing dispatch tables
6534 Elmt := First_Elmt (DT_Aggr);
6535 while Present (Elmt) loop
6536 Set_Is_Dispatch_Table_Entity (Etype (Node (Elmt)));
6537 Next_Elmt (Elmt);
6538 end loop;
6539 end;
6540 end if;
6542 <<Leave_SCIL>>
6544 -- Register the tagged type in the call graph nodes table
6546 Register_CG_Node (Typ);
6548 <<Leave>>
6549 Restore_Ghost_Region (Saved_GM, Saved_IGR);
6551 return Result;
6552 end Make_DT;
6554 -------------------------------------
6555 -- Make_Select_Specific_Data_Table --
6556 -------------------------------------
6558 function Make_Select_Specific_Data_Table
6559 (Typ : Entity_Id) return List_Id
6561 Assignments : constant List_Id := New_List;
6562 Loc : constant Source_Ptr := Sloc (Typ);
6564 Conc_Typ : Entity_Id;
6565 Decls : List_Id := No_List;
6566 Prim : Entity_Id;
6567 Prim_Als : Entity_Id;
6568 Prim_Elmt : Elmt_Id;
6569 Prim_Pos : Uint;
6570 Nb_Prim : Nat := 0;
6572 type Examined_Array is array (Int range <>) of Boolean;
6574 function Find_Entry_Index (E : Entity_Id) return Uint;
6575 -- Given an entry, find its index in the visible declarations of the
6576 -- corresponding concurrent type of Typ.
6578 ----------------------
6579 -- Find_Entry_Index --
6580 ----------------------
6582 function Find_Entry_Index (E : Entity_Id) return Uint is
6583 Index : Uint := Uint_1;
6584 Subp_Decl : Entity_Id;
6586 begin
6587 if Present (Decls)
6588 and then not Is_Empty_List (Decls)
6589 then
6590 Subp_Decl := First (Decls);
6591 while Present (Subp_Decl) loop
6592 if Nkind (Subp_Decl) = N_Entry_Declaration then
6593 if Defining_Identifier (Subp_Decl) = E then
6594 return Index;
6595 end if;
6597 Index := Index + 1;
6598 end if;
6600 Next (Subp_Decl);
6601 end loop;
6602 end if;
6604 return Uint_0;
6605 end Find_Entry_Index;
6607 -- Local variables
6609 Tag_Node : Node_Id;
6611 -- Start of processing for Make_Select_Specific_Data_Table
6613 begin
6614 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
6616 if Present (Corresponding_Concurrent_Type (Typ)) then
6617 Conc_Typ := Corresponding_Concurrent_Type (Typ);
6619 if Present (Full_View (Conc_Typ)) then
6620 Conc_Typ := Full_View (Conc_Typ);
6621 end if;
6623 if Ekind (Conc_Typ) = E_Protected_Type then
6624 Decls := Visible_Declarations (Protected_Definition (
6625 Parent (Conc_Typ)));
6626 else
6627 pragma Assert (Ekind (Conc_Typ) = E_Task_Type);
6628 Decls := Visible_Declarations (Task_Definition (
6629 Parent (Conc_Typ)));
6630 end if;
6631 end if;
6633 -- Count the non-predefined primitive operations
6635 Prim_Elmt := First_Elmt (Primitive_Operations (Typ));
6636 while Present (Prim_Elmt) loop
6637 Prim := Node (Prim_Elmt);
6639 if not (Is_Predefined_Dispatching_Operation (Prim)
6640 or else Is_Predefined_Dispatching_Alias (Prim))
6641 then
6642 Nb_Prim := Nb_Prim + 1;
6643 end if;
6645 Next_Elmt (Prim_Elmt);
6646 end loop;
6648 declare
6649 Examined : Examined_Array (1 .. Nb_Prim) := (others => False);
6651 begin
6652 Prim_Elmt := First_Elmt (Primitive_Operations (Typ));
6653 while Present (Prim_Elmt) loop
6654 Prim := Node (Prim_Elmt);
6656 -- Look for primitive overriding an abstract interface subprogram
6658 if Present (Interface_Alias (Prim))
6659 and then not
6660 Is_Ancestor
6661 (Find_Dispatching_Type (Interface_Alias (Prim)), Typ,
6662 Use_Full_View => True)
6663 and then not Examined (UI_To_Int (DT_Position (Alias (Prim))))
6664 then
6665 Prim_Pos := DT_Position (Alias (Prim));
6666 pragma Assert (UI_To_Int (Prim_Pos) <= Nb_Prim);
6667 Examined (UI_To_Int (Prim_Pos)) := True;
6669 -- Set the primitive operation kind regardless of subprogram
6670 -- type. Generate:
6671 -- Ada.Tags.Set_Prim_Op_Kind (DT_Ptr, <position>, <kind>);
6673 if Tagged_Type_Expansion then
6674 Tag_Node :=
6675 New_Occurrence_Of
6676 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc);
6678 else
6679 Tag_Node :=
6680 Make_Attribute_Reference (Loc,
6681 Prefix => New_Occurrence_Of (Typ, Loc),
6682 Attribute_Name => Name_Tag);
6683 end if;
6685 Append_To (Assignments,
6686 Make_Procedure_Call_Statement (Loc,
6687 Name => New_Occurrence_Of (RTE (RE_Set_Prim_Op_Kind), Loc),
6688 Parameter_Associations => New_List (
6689 Tag_Node,
6690 Make_Integer_Literal (Loc, Prim_Pos),
6691 Prim_Op_Kind (Alias (Prim), Typ))));
6693 -- Retrieve the root of the alias chain
6695 Prim_Als := Ultimate_Alias (Prim);
6697 -- In the case of an entry wrapper, set the entry index
6699 if Ekind (Prim) = E_Procedure
6700 and then Is_Primitive_Wrapper (Prim_Als)
6701 and then Ekind (Wrapped_Entity (Prim_Als)) = E_Entry
6702 then
6703 -- Generate:
6704 -- Ada.Tags.Set_Entry_Index
6705 -- (DT_Ptr, <position>, <index>);
6707 if Tagged_Type_Expansion then
6708 Tag_Node :=
6709 New_Occurrence_Of
6710 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc);
6711 else
6712 Tag_Node :=
6713 Make_Attribute_Reference (Loc,
6714 Prefix => New_Occurrence_Of (Typ, Loc),
6715 Attribute_Name => Name_Tag);
6716 end if;
6718 Append_To (Assignments,
6719 Make_Procedure_Call_Statement (Loc,
6720 Name =>
6721 New_Occurrence_Of (RTE (RE_Set_Entry_Index), Loc),
6722 Parameter_Associations => New_List (
6723 Tag_Node,
6724 Make_Integer_Literal (Loc, Prim_Pos),
6725 Make_Integer_Literal (Loc,
6726 Find_Entry_Index (Wrapped_Entity (Prim_Als))))));
6727 end if;
6728 end if;
6730 Next_Elmt (Prim_Elmt);
6731 end loop;
6732 end;
6734 return Assignments;
6735 end Make_Select_Specific_Data_Table;
6737 ---------------
6738 -- Make_Tags --
6739 ---------------
6741 function Make_Tags (Typ : Entity_Id) return List_Id is
6742 Loc : constant Source_Ptr := Sloc (Typ);
6743 Result : constant List_Id := New_List;
6745 procedure Import_DT
6746 (Tag_Typ : Entity_Id;
6747 DT : Entity_Id;
6748 Is_Secondary_DT : Boolean);
6749 -- Import the dispatch table DT of tagged type Tag_Typ. Required to
6750 -- generate forward references and statically allocate the table. For
6751 -- primary dispatch tables that require no dispatch table generate:
6753 -- DT : static aliased constant Non_Dispatch_Table_Wrapper;
6754 -- pragma Import (Ada, DT);
6756 -- Otherwise generate:
6758 -- DT : static aliased constant Dispatch_Table_Wrapper (Nb_Prim);
6759 -- pragma Import (Ada, DT);
6761 ---------------
6762 -- Import_DT --
6763 ---------------
6765 procedure Import_DT
6766 (Tag_Typ : Entity_Id;
6767 DT : Entity_Id;
6768 Is_Secondary_DT : Boolean)
6770 DT_Constr_List : List_Id;
6771 Nb_Prim : Nat;
6773 begin
6774 Set_Is_Imported (DT);
6775 Set_Ekind (DT, E_Constant);
6776 Set_Related_Type (DT, Typ);
6778 -- The scope must be set now to call Get_External_Name
6780 Set_Scope (DT, Current_Scope);
6782 Get_External_Name (DT);
6783 Set_Interface_Name (DT,
6784 Make_String_Literal (Loc, Strval => String_From_Name_Buffer));
6786 -- Ensure proper Sprint output of this implicit importation
6788 Set_Is_Internal (DT);
6790 -- Save this entity to allow Make_DT to generate its exportation
6792 Append_Elmt (DT, Dispatch_Table_Wrappers (Typ));
6794 -- No dispatch table required
6796 if not Is_Secondary_DT and then not Has_DT (Tag_Typ) then
6797 Append_To (Result,
6798 Make_Object_Declaration (Loc,
6799 Defining_Identifier => DT,
6800 Aliased_Present => True,
6801 Constant_Present => True,
6802 Object_Definition =>
6803 New_Occurrence_Of
6804 (RTE (RE_No_Dispatch_Table_Wrapper), Loc)));
6806 else
6807 -- Calculate the number of primitives of the dispatch table and
6808 -- the size of the Type_Specific_Data record.
6810 Nb_Prim :=
6811 UI_To_Int (DT_Entry_Count (First_Tag_Component (Tag_Typ)));
6813 -- If the tagged type has no primitives we add a dummy slot whose
6814 -- address will be the tag of this type.
6816 if Nb_Prim = 0 then
6817 DT_Constr_List :=
6818 New_List (Make_Integer_Literal (Loc, 1));
6819 else
6820 DT_Constr_List :=
6821 New_List (Make_Integer_Literal (Loc, Nb_Prim));
6822 end if;
6824 Append_To (Result,
6825 Make_Object_Declaration (Loc,
6826 Defining_Identifier => DT,
6827 Aliased_Present => True,
6828 Constant_Present => True,
6829 Object_Definition =>
6830 Make_Subtype_Indication (Loc,
6831 Subtype_Mark =>
6832 New_Occurrence_Of (RTE (RE_Dispatch_Table_Wrapper), Loc),
6833 Constraint => Make_Index_Or_Discriminant_Constraint (Loc,
6834 Constraints => DT_Constr_List))));
6835 end if;
6836 end Import_DT;
6838 -- Local variables
6840 Tname : constant Name_Id := Chars (Typ);
6841 AI_Tag_Comp : Elmt_Id;
6842 DT : Node_Id := Empty;
6843 DT_Ptr : Node_Id;
6844 Predef_Prims_Ptr : Node_Id;
6845 Iface_DT : Node_Id := Empty;
6846 Iface_DT_Ptr : Node_Id;
6847 New_Node : Node_Id;
6848 Suffix_Index : Int;
6849 Typ_Name : Name_Id;
6850 Typ_Comps : Elist_Id;
6852 -- Start of processing for Make_Tags
6854 begin
6855 pragma Assert (No (Access_Disp_Table (Typ)));
6856 Set_Access_Disp_Table (Typ, New_Elmt_List);
6858 -- If the elaboration of this tagged type needs a boolean flag then
6859 -- define now its entity. It is initialized to True to indicate that
6860 -- elaboration is still pending; set to False by the IP routine.
6862 -- TypFxx : boolean := True;
6864 if Elab_Flag_Needed (Typ) then
6865 Set_Access_Disp_Table_Elab_Flag (Typ,
6866 Make_Defining_Identifier (Loc,
6867 Chars => New_External_Name (Tname, 'F')));
6869 Append_To (Result,
6870 Make_Object_Declaration (Loc,
6871 Defining_Identifier => Access_Disp_Table_Elab_Flag (Typ),
6872 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc),
6873 Expression => New_Occurrence_Of (Standard_True, Loc)));
6874 end if;
6876 -- 1) Generate the primary tag entities
6878 -- Primary dispatch table containing user-defined primitives
6880 DT_Ptr := Make_Defining_Identifier (Loc, New_External_Name (Tname, 'P'));
6881 Set_Etype (DT_Ptr, RTE (RE_Tag));
6882 Append_Elmt (DT_Ptr, Access_Disp_Table (Typ));
6884 -- Minimum decoration
6886 Set_Ekind (DT_Ptr, E_Variable);
6887 Set_Related_Type (DT_Ptr, Typ);
6889 -- Notify back end that the types are associated with a dispatch table
6891 Set_Is_Dispatch_Table_Entity (RTE (RE_Prim_Ptr));
6892 Set_Is_Dispatch_Table_Entity (RTE (RE_Predef_Prims_Table_Ptr));
6894 -- For CPP types there is no need to build the dispatch tables since
6895 -- they are imported from the C++ side. If the CPP type has an IP then
6896 -- we declare now the variable that will store the copy of the C++ tag.
6897 -- If the CPP type is an interface, we need the variable as well because
6898 -- it becomes the pointer to the corresponding secondary table.
6900 if Is_CPP_Class (Typ) then
6901 if Has_CPP_Constructors (Typ) or else Is_Interface (Typ) then
6902 Append_To (Result,
6903 Make_Object_Declaration (Loc,
6904 Defining_Identifier => DT_Ptr,
6905 Object_Definition => New_Occurrence_Of (RTE (RE_Tag), Loc),
6906 Expression =>
6907 Unchecked_Convert_To (RTE (RE_Tag),
6908 New_Occurrence_Of (RTE (RE_Null_Address), Loc))));
6910 Set_Is_Statically_Allocated (DT_Ptr,
6911 Is_Library_Level_Tagged_Type (Typ));
6912 end if;
6914 -- Ada types
6916 else
6917 -- Primary dispatch table containing predefined primitives
6919 Predef_Prims_Ptr :=
6920 Make_Defining_Identifier (Loc,
6921 Chars => New_External_Name (Tname, 'Y'));
6922 Set_Etype (Predef_Prims_Ptr, RTE (RE_Address));
6923 Append_Elmt (Predef_Prims_Ptr, Access_Disp_Table (Typ));
6925 -- Import the forward declaration of the Dispatch Table wrapper
6926 -- record (Make_DT will take care of exporting it).
6928 if Building_Static_DT (Typ) then
6929 Set_Dispatch_Table_Wrappers (Typ, New_Elmt_List);
6931 DT :=
6932 Make_Defining_Identifier (Loc,
6933 Chars => New_External_Name (Tname, 'T'));
6935 Import_DT (Typ, DT, Is_Secondary_DT => False);
6937 if Has_DT (Typ) then
6938 Append_To (Result,
6939 Make_Object_Declaration (Loc,
6940 Defining_Identifier => DT_Ptr,
6941 Constant_Present => True,
6942 Object_Definition =>
6943 New_Occurrence_Of (RTE (RE_Tag), Loc),
6944 Expression =>
6945 Unchecked_Convert_To (RTE (RE_Tag),
6946 Make_Attribute_Reference (Loc,
6947 Prefix =>
6948 Make_Selected_Component (Loc,
6949 Prefix => New_Occurrence_Of (DT, Loc),
6950 Selector_Name =>
6951 New_Occurrence_Of
6952 (RTE_Record_Component (RE_Prims_Ptr), Loc)),
6953 Attribute_Name => Name_Address))));
6955 -- Generate the SCIL node for the previous object declaration
6956 -- because it has a tag initialization.
6958 if Generate_SCIL then
6959 New_Node :=
6960 Make_SCIL_Dispatch_Table_Tag_Init (Sloc (Last (Result)));
6961 Set_SCIL_Entity (New_Node, Typ);
6962 Set_SCIL_Node (Last (Result), New_Node);
6963 end if;
6965 Append_To (Result,
6966 Make_Object_Declaration (Loc,
6967 Defining_Identifier => Predef_Prims_Ptr,
6968 Constant_Present => True,
6969 Object_Definition =>
6970 New_Occurrence_Of (RTE (RE_Address), Loc),
6971 Expression =>
6972 Make_Attribute_Reference (Loc,
6973 Prefix =>
6974 Make_Selected_Component (Loc,
6975 Prefix => New_Occurrence_Of (DT, Loc),
6976 Selector_Name =>
6977 New_Occurrence_Of
6978 (RTE_Record_Component (RE_Predef_Prims), Loc)),
6979 Attribute_Name => Name_Address)));
6981 -- No dispatch table required
6983 else
6984 Append_To (Result,
6985 Make_Object_Declaration (Loc,
6986 Defining_Identifier => DT_Ptr,
6987 Constant_Present => True,
6988 Object_Definition =>
6989 New_Occurrence_Of (RTE (RE_Tag), Loc),
6990 Expression =>
6991 Unchecked_Convert_To (RTE (RE_Tag),
6992 Make_Attribute_Reference (Loc,
6993 Prefix =>
6994 Make_Selected_Component (Loc,
6995 Prefix => New_Occurrence_Of (DT, Loc),
6996 Selector_Name =>
6997 New_Occurrence_Of
6998 (RTE_Record_Component (RE_NDT_Prims_Ptr),
6999 Loc)),
7000 Attribute_Name => Name_Address))));
7001 end if;
7003 Set_Is_True_Constant (DT_Ptr);
7004 Set_Is_Statically_Allocated (DT_Ptr);
7005 end if;
7006 end if;
7008 -- 2) Generate the secondary tag entities
7010 -- Collect the components associated with secondary dispatch tables
7012 if Has_Interfaces (Typ) then
7013 Collect_Interface_Components (Typ, Typ_Comps);
7015 -- For each interface type we build a unique external name associated
7016 -- with its secondary dispatch table. This name is used to declare an
7017 -- object that references this secondary dispatch table, whose value
7018 -- will be used for the elaboration of Typ objects, and also for the
7019 -- elaboration of objects of types derived from Typ that do not
7020 -- override the primitives of this interface type.
7022 Suffix_Index := 1;
7024 -- Note: The value of Suffix_Index must be in sync with the values of
7025 -- Suffix_Index in secondary dispatch tables generated by Make_DT.
7027 if Is_CPP_Class (Typ) then
7028 AI_Tag_Comp := First_Elmt (Typ_Comps);
7029 while Present (AI_Tag_Comp) loop
7030 Get_Secondary_DT_External_Name
7031 (Typ, Related_Type (Node (AI_Tag_Comp)), Suffix_Index);
7032 Typ_Name := Name_Find;
7034 -- Declare variables to store copy of the C++ secondary tags
7036 Iface_DT_Ptr :=
7037 Make_Defining_Identifier (Loc,
7038 Chars => New_External_Name (Typ_Name, 'P'));
7039 Set_Etype (Iface_DT_Ptr, RTE (RE_Interface_Tag));
7040 Set_Ekind (Iface_DT_Ptr, E_Variable);
7041 Set_Is_Tag (Iface_DT_Ptr);
7043 Set_Has_Thunks (Iface_DT_Ptr);
7044 Set_Related_Type
7045 (Iface_DT_Ptr, Related_Type (Node (AI_Tag_Comp)));
7046 Append_Elmt (Iface_DT_Ptr, Access_Disp_Table (Typ));
7048 Append_To (Result,
7049 Make_Object_Declaration (Loc,
7050 Defining_Identifier => Iface_DT_Ptr,
7051 Object_Definition => New_Occurrence_Of
7052 (RTE (RE_Interface_Tag), Loc),
7053 Expression =>
7054 Unchecked_Convert_To (RTE (RE_Interface_Tag),
7055 New_Occurrence_Of (RTE (RE_Null_Address), Loc))));
7057 Set_Is_Statically_Allocated (Iface_DT_Ptr,
7058 Is_Library_Level_Tagged_Type (Typ));
7060 Next_Elmt (AI_Tag_Comp);
7061 end loop;
7063 -- This is not a CPP_Class type
7065 else
7066 AI_Tag_Comp := First_Elmt (Typ_Comps);
7067 while Present (AI_Tag_Comp) loop
7068 Get_Secondary_DT_External_Name
7069 (Typ, Related_Type (Node (AI_Tag_Comp)), Suffix_Index);
7070 Typ_Name := Name_Find;
7072 if Building_Static_DT (Typ) then
7073 Iface_DT :=
7074 Make_Defining_Identifier (Loc,
7075 Chars => New_External_Name (Typ_Name, 'T'));
7076 Import_DT
7077 (Tag_Typ => Related_Type (Node (AI_Tag_Comp)),
7078 DT => Iface_DT,
7079 Is_Secondary_DT => True);
7080 end if;
7082 -- Secondary dispatch table referencing thunks to user-defined
7083 -- primitives covered by this interface.
7085 Iface_DT_Ptr :=
7086 Make_Defining_Identifier (Loc,
7087 Chars => New_External_Name (Typ_Name, 'P'));
7088 Set_Etype (Iface_DT_Ptr, RTE (RE_Interface_Tag));
7089 Set_Ekind (Iface_DT_Ptr, E_Constant);
7090 Set_Is_Tag (Iface_DT_Ptr);
7091 Set_Has_Thunks (Iface_DT_Ptr);
7092 Set_Is_Statically_Allocated (Iface_DT_Ptr,
7093 Is_Library_Level_Tagged_Type (Typ));
7094 Set_Is_True_Constant (Iface_DT_Ptr);
7095 Set_Related_Type
7096 (Iface_DT_Ptr, Related_Type (Node (AI_Tag_Comp)));
7097 Append_Elmt (Iface_DT_Ptr, Access_Disp_Table (Typ));
7099 if Building_Static_DT (Typ) then
7100 Append_To (Result,
7101 Make_Object_Declaration (Loc,
7102 Defining_Identifier => Iface_DT_Ptr,
7103 Constant_Present => True,
7104 Object_Definition => New_Occurrence_Of
7105 (RTE (RE_Interface_Tag), Loc),
7106 Expression =>
7107 Unchecked_Convert_To (RTE (RE_Interface_Tag),
7108 Make_Attribute_Reference (Loc,
7109 Prefix =>
7110 Make_Selected_Component (Loc,
7111 Prefix =>
7112 New_Occurrence_Of (Iface_DT, Loc),
7113 Selector_Name =>
7114 New_Occurrence_Of
7115 (RTE_Record_Component (RE_Prims_Ptr),
7116 Loc)),
7117 Attribute_Name => Name_Address))));
7118 end if;
7120 -- Secondary dispatch table referencing thunks to predefined
7121 -- primitives.
7123 Iface_DT_Ptr :=
7124 Make_Defining_Identifier (Loc,
7125 Chars => New_External_Name (Typ_Name, 'Y'));
7126 Set_Etype (Iface_DT_Ptr, RTE (RE_Address));
7127 Set_Ekind (Iface_DT_Ptr, E_Constant);
7128 Set_Is_Tag (Iface_DT_Ptr);
7129 Set_Has_Thunks (Iface_DT_Ptr);
7130 Set_Is_Statically_Allocated (Iface_DT_Ptr,
7131 Is_Library_Level_Tagged_Type (Typ));
7132 Set_Is_True_Constant (Iface_DT_Ptr);
7133 Set_Related_Type
7134 (Iface_DT_Ptr, Related_Type (Node (AI_Tag_Comp)));
7135 Append_Elmt (Iface_DT_Ptr, Access_Disp_Table (Typ));
7137 -- Secondary dispatch table referencing user-defined primitives
7138 -- covered by this interface.
7140 Iface_DT_Ptr :=
7141 Make_Defining_Identifier (Loc,
7142 Chars => New_External_Name (Typ_Name, 'D'));
7143 Set_Etype (Iface_DT_Ptr, RTE (RE_Interface_Tag));
7144 Set_Ekind (Iface_DT_Ptr, E_Constant);
7145 Set_Is_Tag (Iface_DT_Ptr);
7146 Set_Is_Statically_Allocated (Iface_DT_Ptr,
7147 Is_Library_Level_Tagged_Type (Typ));
7148 Set_Is_True_Constant (Iface_DT_Ptr);
7149 Set_Related_Type
7150 (Iface_DT_Ptr, Related_Type (Node (AI_Tag_Comp)));
7151 Append_Elmt (Iface_DT_Ptr, Access_Disp_Table (Typ));
7153 -- Secondary dispatch table referencing predefined primitives
7155 Iface_DT_Ptr :=
7156 Make_Defining_Identifier (Loc,
7157 Chars => New_External_Name (Typ_Name, 'Z'));
7158 Set_Etype (Iface_DT_Ptr, RTE (RE_Address));
7159 Set_Ekind (Iface_DT_Ptr, E_Constant);
7160 Set_Is_Tag (Iface_DT_Ptr);
7161 Set_Is_Statically_Allocated (Iface_DT_Ptr,
7162 Is_Library_Level_Tagged_Type (Typ));
7163 Set_Is_True_Constant (Iface_DT_Ptr);
7164 Set_Related_Type
7165 (Iface_DT_Ptr, Related_Type (Node (AI_Tag_Comp)));
7166 Append_Elmt (Iface_DT_Ptr, Access_Disp_Table (Typ));
7168 Next_Elmt (AI_Tag_Comp);
7169 end loop;
7170 end if;
7171 end if;
7173 -- 3) At the end of Access_Disp_Table, if the type has user-defined
7174 -- primitives, we add the entity of an access type declaration that
7175 -- is used by Build_Get_Prim_Op_Address to expand dispatching calls
7176 -- through the primary dispatch table.
7178 if UI_To_Int (DT_Entry_Count (First_Tag_Component (Typ))) = 0 then
7179 Analyze_List (Result);
7181 -- Generate:
7182 -- type Typ_DT is array (1 .. Nb_Prims) of Prim_Ptr;
7183 -- type Typ_DT_Acc is access Typ_DT;
7185 else
7186 declare
7187 Name_DT_Prims : constant Name_Id :=
7188 New_External_Name (Tname, 'G');
7189 Name_DT_Prims_Acc : constant Name_Id :=
7190 New_External_Name (Tname, 'H');
7191 DT_Prims : constant Entity_Id :=
7192 Make_Defining_Identifier (Loc,
7193 Name_DT_Prims);
7194 DT_Prims_Acc : constant Entity_Id :=
7195 Make_Defining_Identifier (Loc,
7196 Name_DT_Prims_Acc);
7197 begin
7198 Append_To (Result,
7199 Make_Full_Type_Declaration (Loc,
7200 Defining_Identifier => DT_Prims,
7201 Type_Definition =>
7202 Make_Constrained_Array_Definition (Loc,
7203 Discrete_Subtype_Definitions => New_List (
7204 Make_Range (Loc,
7205 Low_Bound => Make_Integer_Literal (Loc, 1),
7206 High_Bound => Make_Integer_Literal (Loc,
7207 DT_Entry_Count
7208 (First_Tag_Component (Typ))))),
7209 Component_Definition =>
7210 Make_Component_Definition (Loc,
7211 Subtype_Indication =>
7212 New_Occurrence_Of (RTE (RE_Prim_Ptr), Loc)))));
7214 Append_To (Result,
7215 Make_Full_Type_Declaration (Loc,
7216 Defining_Identifier => DT_Prims_Acc,
7217 Type_Definition =>
7218 Make_Access_To_Object_Definition (Loc,
7219 Subtype_Indication =>
7220 New_Occurrence_Of (DT_Prims, Loc))));
7222 Append_Elmt (DT_Prims_Acc, Access_Disp_Table (Typ));
7224 -- Analyze the resulting list and suppress the generation of the
7225 -- Init_Proc associated with the above array declaration because
7226 -- this type is never used in object declarations. It is only used
7227 -- to simplify the expansion associated with dispatching calls.
7229 Analyze_List (Result);
7230 Set_Suppress_Initialization (Base_Type (DT_Prims));
7232 -- Disable backend optimizations based on assumptions about the
7233 -- aliasing status of objects designated by the access to the
7234 -- dispatch table. Required to handle dispatch tables imported
7235 -- from C++.
7237 Set_No_Strict_Aliasing (Base_Type (DT_Prims_Acc));
7239 -- Add the freezing nodes of these declarations; required to avoid
7240 -- generating these freezing nodes in wrong scopes (for example in
7241 -- the IC routine of a derivation of Typ).
7243 -- What is an "IC routine"? Is "init_proc" meant here???
7245 Append_List_To (Result, Freeze_Entity (DT_Prims, Typ));
7246 Append_List_To (Result, Freeze_Entity (DT_Prims_Acc, Typ));
7248 -- Mark entity of dispatch table. Required by the back end to
7249 -- handle them properly.
7251 Set_Is_Dispatch_Table_Entity (DT_Prims);
7252 end;
7253 end if;
7255 -- Mark entities of dispatch table. Required by the back end to handle
7256 -- them properly.
7258 if Present (DT) then
7259 Set_Is_Dispatch_Table_Entity (DT);
7260 Set_Is_Dispatch_Table_Entity (Etype (DT));
7261 end if;
7263 if Present (Iface_DT) then
7264 Set_Is_Dispatch_Table_Entity (Iface_DT);
7265 Set_Is_Dispatch_Table_Entity (Etype (Iface_DT));
7266 end if;
7268 if Is_CPP_Class (Root_Type (Typ)) then
7269 Set_Ekind (DT_Ptr, E_Variable);
7270 else
7271 Set_Ekind (DT_Ptr, E_Constant);
7272 end if;
7274 Set_Is_Tag (DT_Ptr);
7275 Set_Related_Type (DT_Ptr, Typ);
7277 return Result;
7278 end Make_Tags;
7280 ---------------
7281 -- New_Value --
7282 ---------------
7284 function New_Value (From : Node_Id) return Node_Id is
7285 Res : constant Node_Id := Duplicate_Subexpr (From);
7286 begin
7287 if Is_Access_Type (Etype (From)) then
7288 return Make_Explicit_Dereference (Sloc (From), Prefix => Res);
7289 else
7290 return Res;
7291 end if;
7292 end New_Value;
7294 -----------------------------------
7295 -- Original_View_In_Visible_Part --
7296 -----------------------------------
7298 function Original_View_In_Visible_Part (Typ : Entity_Id) return Boolean is
7299 Scop : constant Entity_Id := Scope (Typ);
7301 begin
7302 -- The scope must be a package
7304 if not Is_Package_Or_Generic_Package (Scop) then
7305 return False;
7306 end if;
7308 -- A type with a private declaration has a private view declared in
7309 -- the visible part.
7311 if Has_Private_Declaration (Typ) then
7312 return True;
7313 end if;
7315 return List_Containing (Parent (Typ)) =
7316 Visible_Declarations (Package_Specification (Scop));
7317 end Original_View_In_Visible_Part;
7319 ------------------
7320 -- Prim_Op_Kind --
7321 ------------------
7323 function Prim_Op_Kind
7324 (Prim : Entity_Id;
7325 Typ : Entity_Id) return Node_Id
7327 Full_Typ : Entity_Id := Typ;
7328 Loc : constant Source_Ptr := Sloc (Prim);
7329 Prim_Op : Entity_Id;
7331 begin
7332 -- Retrieve the original primitive operation
7334 Prim_Op := Ultimate_Alias (Prim);
7336 if Ekind (Typ) = E_Record_Type
7337 and then Present (Corresponding_Concurrent_Type (Typ))
7338 then
7339 Full_Typ := Corresponding_Concurrent_Type (Typ);
7340 end if;
7342 -- When a private tagged type is completed by a concurrent type,
7343 -- retrieve the full view.
7345 if Is_Private_Type (Full_Typ) then
7346 Full_Typ := Full_View (Full_Typ);
7347 end if;
7349 if Ekind (Prim_Op) = E_Function then
7351 -- Protected function
7353 if Ekind (Full_Typ) = E_Protected_Type then
7354 return New_Occurrence_Of (RTE (RE_POK_Protected_Function), Loc);
7356 -- Task function
7358 elsif Ekind (Full_Typ) = E_Task_Type then
7359 return New_Occurrence_Of (RTE (RE_POK_Task_Function), Loc);
7361 -- Regular function
7363 else
7364 return New_Occurrence_Of (RTE (RE_POK_Function), Loc);
7365 end if;
7367 else
7368 pragma Assert (Ekind (Prim_Op) = E_Procedure);
7370 if Ekind (Full_Typ) = E_Protected_Type then
7372 -- Protected entry
7374 if Is_Primitive_Wrapper (Prim_Op)
7375 and then Ekind (Wrapped_Entity (Prim_Op)) = E_Entry
7376 then
7377 return New_Occurrence_Of (RTE (RE_POK_Protected_Entry), Loc);
7379 -- Protected procedure
7381 else
7382 return
7383 New_Occurrence_Of (RTE (RE_POK_Protected_Procedure), Loc);
7384 end if;
7386 elsif Ekind (Full_Typ) = E_Task_Type then
7388 -- Task entry
7390 if Is_Primitive_Wrapper (Prim_Op)
7391 and then Ekind (Wrapped_Entity (Prim_Op)) = E_Entry
7392 then
7393 return New_Occurrence_Of (RTE (RE_POK_Task_Entry), Loc);
7395 -- Task "procedure". These are the internally Expander-generated
7396 -- procedures (task body for instance).
7398 else
7399 return New_Occurrence_Of (RTE (RE_POK_Task_Procedure), Loc);
7400 end if;
7402 -- Regular procedure
7404 else
7405 return New_Occurrence_Of (RTE (RE_POK_Procedure), Loc);
7406 end if;
7407 end if;
7408 end Prim_Op_Kind;
7410 ------------------------
7411 -- Register_Primitive --
7412 ------------------------
7414 function Register_Primitive
7415 (Loc : Source_Ptr;
7416 Prim : Entity_Id) return List_Id
7418 DT_Ptr : Entity_Id;
7419 Iface_Prim : Entity_Id;
7420 Iface_Typ : Entity_Id;
7421 Iface_DT_Ptr : Entity_Id;
7422 Iface_DT_Elmt : Elmt_Id;
7423 L : constant List_Id := New_List;
7424 Pos : Uint;
7425 Tag : Entity_Id;
7426 Tag_Typ : Entity_Id;
7427 Thunk_Id : Entity_Id;
7428 Thunk_Code : Node_Id;
7430 begin
7431 pragma Assert (not Restriction_Active (No_Dispatching_Calls));
7433 -- Do not register in the dispatch table eliminated primitives
7435 if not RTE_Available (RE_Tag)
7436 or else Is_Eliminated (Ultimate_Alias (Prim))
7437 or else Generate_SCIL
7438 then
7439 return L;
7440 end if;
7442 if not Present (Interface_Alias (Prim)) then
7443 Tag_Typ := Scope (DTC_Entity (Prim));
7444 Pos := DT_Position (Prim);
7445 Tag := First_Tag_Component (Tag_Typ);
7447 if Is_Predefined_Dispatching_Operation (Prim)
7448 or else Is_Predefined_Dispatching_Alias (Prim)
7449 then
7450 DT_Ptr :=
7451 Node (Next_Elmt (First_Elmt (Access_Disp_Table (Tag_Typ))));
7453 Append_To (L,
7454 Build_Set_Predefined_Prim_Op_Address (Loc,
7455 Tag_Node => New_Occurrence_Of (DT_Ptr, Loc),
7456 Position => Pos,
7457 Address_Node =>
7458 Unchecked_Convert_To (RTE (RE_Prim_Ptr),
7459 Make_Attribute_Reference (Loc,
7460 Prefix => New_Occurrence_Of (Prim, Loc),
7461 Attribute_Name => Name_Unrestricted_Access))));
7463 -- Register copy of the pointer to the 'size primitive in the TSD
7465 if Chars (Prim) = Name_uSize
7466 and then RTE_Record_Component_Available (RE_Size_Func)
7467 then
7468 DT_Ptr := Node (First_Elmt (Access_Disp_Table (Tag_Typ)));
7469 Append_To (L,
7470 Build_Set_Size_Function (Loc,
7471 Tag_Node => New_Occurrence_Of (DT_Ptr, Loc),
7472 Size_Func => Prim));
7473 end if;
7475 else
7476 pragma Assert (Pos /= Uint_0 and then Pos <= DT_Entry_Count (Tag));
7478 -- Skip registration of primitives located in the C++ part of the
7479 -- dispatch table. Their slot is set by the IC routine.
7481 if not Is_CPP_Class (Root_Type (Tag_Typ))
7482 or else Pos > CPP_Num_Prims (Tag_Typ)
7483 then
7484 DT_Ptr := Node (First_Elmt (Access_Disp_Table (Tag_Typ)));
7485 Append_To (L,
7486 Build_Set_Prim_Op_Address (Loc,
7487 Typ => Tag_Typ,
7488 Tag_Node => New_Occurrence_Of (DT_Ptr, Loc),
7489 Position => Pos,
7490 Address_Node =>
7491 Unchecked_Convert_To (RTE (RE_Prim_Ptr),
7492 Make_Attribute_Reference (Loc,
7493 Prefix => New_Occurrence_Of (Prim, Loc),
7494 Attribute_Name => Name_Unrestricted_Access))));
7495 end if;
7496 end if;
7498 -- Ada 2005 (AI-251): Primitive associated with an interface type
7500 -- Generate the code of the thunk only if the interface type is not an
7501 -- immediate ancestor of Typ; otherwise the dispatch table associated
7502 -- with the interface is the primary dispatch table and we have nothing
7503 -- else to do here.
7505 else
7506 Tag_Typ := Find_Dispatching_Type (Alias (Prim));
7507 Iface_Typ := Find_Dispatching_Type (Interface_Alias (Prim));
7509 pragma Assert (Is_Interface (Iface_Typ));
7511 -- No action needed for interfaces that are ancestors of Typ because
7512 -- their primitives are located in the primary dispatch table.
7514 if Is_Ancestor (Iface_Typ, Tag_Typ, Use_Full_View => True) then
7515 return L;
7517 -- No action needed for primitives located in the C++ part of the
7518 -- dispatch table. Their slot is set by the IC routine.
7520 elsif Is_CPP_Class (Root_Type (Tag_Typ))
7521 and then DT_Position (Alias (Prim)) <= CPP_Num_Prims (Tag_Typ)
7522 and then not Is_Predefined_Dispatching_Operation (Prim)
7523 and then not Is_Predefined_Dispatching_Alias (Prim)
7524 then
7525 return L;
7526 end if;
7528 Expand_Interface_Thunk (Prim, Thunk_Id, Thunk_Code);
7530 if not Is_Ancestor (Iface_Typ, Tag_Typ, Use_Full_View => True)
7531 and then Present (Thunk_Code)
7532 then
7533 -- Generate the code necessary to fill the appropriate entry of
7534 -- the secondary dispatch table of Prim's controlling type with
7535 -- Thunk_Id's address.
7537 Iface_DT_Elmt := Find_Interface_ADT (Tag_Typ, Iface_Typ);
7538 Iface_DT_Ptr := Node (Iface_DT_Elmt);
7539 pragma Assert (Has_Thunks (Iface_DT_Ptr));
7541 Iface_Prim := Interface_Alias (Prim);
7542 Pos := DT_Position (Iface_Prim);
7543 Tag := First_Tag_Component (Iface_Typ);
7545 Prepend_To (L, Thunk_Code);
7547 if Is_Predefined_Dispatching_Operation (Prim)
7548 or else Is_Predefined_Dispatching_Alias (Prim)
7549 then
7550 Append_To (L,
7551 Build_Set_Predefined_Prim_Op_Address (Loc,
7552 Tag_Node =>
7553 New_Occurrence_Of (Node (Next_Elmt (Iface_DT_Elmt)), Loc),
7554 Position => Pos,
7555 Address_Node =>
7556 Unchecked_Convert_To (RTE (RE_Prim_Ptr),
7557 Make_Attribute_Reference (Loc,
7558 Prefix => New_Occurrence_Of (Thunk_Id, Loc),
7559 Attribute_Name => Name_Unrestricted_Access))));
7561 Next_Elmt (Iface_DT_Elmt);
7562 Next_Elmt (Iface_DT_Elmt);
7563 Iface_DT_Ptr := Node (Iface_DT_Elmt);
7564 pragma Assert (not Has_Thunks (Iface_DT_Ptr));
7566 Append_To (L,
7567 Build_Set_Predefined_Prim_Op_Address (Loc,
7568 Tag_Node =>
7569 New_Occurrence_Of (Node (Next_Elmt (Iface_DT_Elmt)), Loc),
7570 Position => Pos,
7571 Address_Node =>
7572 Unchecked_Convert_To (RTE (RE_Prim_Ptr),
7573 Make_Attribute_Reference (Loc,
7574 Prefix =>
7575 New_Occurrence_Of (Alias (Prim), Loc),
7576 Attribute_Name => Name_Unrestricted_Access))));
7578 else
7579 pragma Assert (Pos /= Uint_0
7580 and then Pos <= DT_Entry_Count (Tag));
7582 Append_To (L,
7583 Build_Set_Prim_Op_Address (Loc,
7584 Typ => Iface_Typ,
7585 Tag_Node => New_Occurrence_Of (Iface_DT_Ptr, Loc),
7586 Position => Pos,
7587 Address_Node =>
7588 Unchecked_Convert_To (RTE (RE_Prim_Ptr),
7589 Make_Attribute_Reference (Loc,
7590 Prefix => New_Occurrence_Of (Thunk_Id, Loc),
7591 Attribute_Name => Name_Unrestricted_Access))));
7593 Next_Elmt (Iface_DT_Elmt);
7594 Next_Elmt (Iface_DT_Elmt);
7595 Iface_DT_Ptr := Node (Iface_DT_Elmt);
7596 pragma Assert (not Has_Thunks (Iface_DT_Ptr));
7598 Append_To (L,
7599 Build_Set_Prim_Op_Address (Loc,
7600 Typ => Iface_Typ,
7601 Tag_Node => New_Occurrence_Of (Iface_DT_Ptr, Loc),
7602 Position => Pos,
7603 Address_Node =>
7604 Unchecked_Convert_To (RTE (RE_Prim_Ptr),
7605 Make_Attribute_Reference (Loc,
7606 Prefix =>
7607 New_Occurrence_Of (Alias (Prim), Loc),
7608 Attribute_Name => Name_Unrestricted_Access))));
7610 end if;
7611 end if;
7612 end if;
7614 return L;
7615 end Register_Primitive;
7617 -------------------------
7618 -- Set_All_DT_Position --
7619 -------------------------
7621 procedure Set_All_DT_Position (Typ : Entity_Id) is
7623 function In_Predef_Prims_DT (Prim : Entity_Id) return Boolean;
7624 -- Returns True if Prim is located in the dispatch table of
7625 -- predefined primitives
7627 procedure Validate_Position (Prim : Entity_Id);
7628 -- Check that position assigned to Prim is completely safe (it has not
7629 -- been assigned to a previously defined primitive operation of Typ).
7631 ------------------------
7632 -- In_Predef_Prims_DT --
7633 ------------------------
7635 function In_Predef_Prims_DT (Prim : Entity_Id) return Boolean is
7636 begin
7637 -- Predefined primitives
7639 if Is_Predefined_Dispatching_Operation (Prim) then
7640 return True;
7642 -- Renamings of predefined primitives
7644 elsif Present (Alias (Prim))
7645 and then Is_Predefined_Dispatching_Operation (Ultimate_Alias (Prim))
7646 then
7647 if Chars (Ultimate_Alias (Prim)) /= Name_Op_Eq then
7648 return True;
7650 -- An overriding operation that is a user-defined renaming of
7651 -- predefined equality inherits its slot from the overridden
7652 -- operation. Otherwise it is treated as a predefined op and
7653 -- occupies the same predefined slot as equality. A call to it is
7654 -- transformed into a call to its alias, which is the predefined
7655 -- equality op. A dispatching call thus uses the proper slot if
7656 -- operation is further inherited and called with class-wide
7657 -- arguments.
7659 else
7660 return
7661 not Comes_From_Source (Prim)
7662 or else No (Overridden_Operation (Prim));
7663 end if;
7665 -- User-defined primitives
7667 else
7668 return False;
7669 end if;
7670 end In_Predef_Prims_DT;
7672 -----------------------
7673 -- Validate_Position --
7674 -----------------------
7676 procedure Validate_Position (Prim : Entity_Id) is
7677 Op_Elmt : Elmt_Id;
7678 Op : Entity_Id;
7680 begin
7681 -- Aliased primitives are safe
7683 if Present (Alias (Prim)) then
7684 return;
7685 end if;
7687 Op_Elmt := First_Elmt (Primitive_Operations (Typ));
7688 while Present (Op_Elmt) loop
7689 Op := Node (Op_Elmt);
7691 -- No need to check against itself
7693 if Op = Prim then
7694 null;
7696 -- Primitive operations covering abstract interfaces are
7697 -- allocated later
7699 elsif Present (Interface_Alias (Op)) then
7700 null;
7702 -- Predefined dispatching operations are completely safe. They
7703 -- are allocated at fixed positions in a separate table.
7705 elsif Is_Predefined_Dispatching_Operation (Op)
7706 or else Is_Predefined_Dispatching_Alias (Op)
7707 then
7708 null;
7710 -- Aliased subprograms are safe
7712 elsif Present (Alias (Op)) then
7713 null;
7715 elsif DT_Position (Op) = DT_Position (Prim)
7716 and then not Is_Predefined_Dispatching_Operation (Op)
7717 and then not Is_Predefined_Dispatching_Operation (Prim)
7718 and then not Is_Predefined_Dispatching_Alias (Op)
7719 and then not Is_Predefined_Dispatching_Alias (Prim)
7720 then
7721 -- Handle aliased subprograms
7723 declare
7724 Op_1 : Entity_Id;
7725 Op_2 : Entity_Id;
7727 begin
7728 Op_1 := Op;
7729 loop
7730 if Present (Overridden_Operation (Op_1)) then
7731 Op_1 := Overridden_Operation (Op_1);
7732 elsif Present (Alias (Op_1)) then
7733 Op_1 := Alias (Op_1);
7734 else
7735 exit;
7736 end if;
7737 end loop;
7739 Op_2 := Prim;
7740 loop
7741 if Present (Overridden_Operation (Op_2)) then
7742 Op_2 := Overridden_Operation (Op_2);
7743 elsif Present (Alias (Op_2)) then
7744 Op_2 := Alias (Op_2);
7745 else
7746 exit;
7747 end if;
7748 end loop;
7750 if Op_1 /= Op_2 then
7751 raise Program_Error;
7752 end if;
7753 end;
7754 end if;
7756 Next_Elmt (Op_Elmt);
7757 end loop;
7758 end Validate_Position;
7760 -- Local variables
7762 Parent_Typ : constant Entity_Id := Etype (Typ);
7763 First_Prim : constant Elmt_Id := First_Elmt (Primitive_Operations (Typ));
7764 The_Tag : constant Entity_Id := First_Tag_Component (Typ);
7766 Adjusted : Boolean := False;
7767 Finalized : Boolean := False;
7769 Count_Prim : Nat;
7770 DT_Length : Nat;
7771 Nb_Prim : Nat;
7772 Prim : Entity_Id;
7773 Prim_Elmt : Elmt_Id;
7775 -- Start of processing for Set_All_DT_Position
7777 begin
7778 pragma Assert (Present (First_Tag_Component (Typ)));
7780 -- Set the DT_Position for each primitive operation. Perform some sanity
7781 -- checks to avoid building inconsistent dispatch tables.
7783 -- First stage: Set DTC entity of all the primitive operations. This is
7784 -- required to properly read the DT_Position attribute in latter stages.
7786 Prim_Elmt := First_Prim;
7787 Count_Prim := 0;
7788 while Present (Prim_Elmt) loop
7789 Prim := Node (Prim_Elmt);
7791 -- Predefined primitives have a separate dispatch table
7793 if not In_Predef_Prims_DT (Prim) then
7794 Count_Prim := Count_Prim + 1;
7795 end if;
7797 Set_DTC_Entity_Value (Typ, Prim);
7799 -- Clear any previous value of the DT_Position attribute. In this
7800 -- way we ensure that the final position of all the primitives is
7801 -- established by the following stages of this algorithm.
7803 Set_DT_Position_Value (Prim, No_Uint);
7805 Next_Elmt (Prim_Elmt);
7806 end loop;
7808 declare
7809 Fixed_Prim : array (Int range 0 .. Count_Prim) of Boolean :=
7810 (others => False);
7812 E : Entity_Id;
7814 procedure Handle_Inherited_Private_Subprograms (Typ : Entity_Id);
7815 -- Called if Typ is declared in a nested package or a public child
7816 -- package to handle inherited primitives that were inherited by Typ
7817 -- in the visible part, but whose declaration was deferred because
7818 -- the parent operation was private and not visible at that point.
7820 procedure Set_Fixed_Prim (Pos : Nat);
7821 -- Sets to true an element of the Fixed_Prim table to indicate
7822 -- that this entry of the dispatch table of Typ is occupied.
7824 ------------------------------------------
7825 -- Handle_Inherited_Private_Subprograms --
7826 ------------------------------------------
7828 procedure Handle_Inherited_Private_Subprograms (Typ : Entity_Id) is
7829 Op_List : Elist_Id;
7830 Op_Elmt : Elmt_Id;
7831 Op_Elmt_2 : Elmt_Id;
7832 Prim_Op : Entity_Id;
7833 Parent_Subp : Entity_Id;
7835 begin
7836 Op_List := Primitive_Operations (Typ);
7838 Op_Elmt := First_Elmt (Op_List);
7839 while Present (Op_Elmt) loop
7840 Prim_Op := Node (Op_Elmt);
7842 -- Search primitives that are implicit operations with an
7843 -- internal name whose parent operation has a normal name.
7845 if Present (Alias (Prim_Op))
7846 and then Find_Dispatching_Type (Alias (Prim_Op)) /= Typ
7847 and then not Comes_From_Source (Prim_Op)
7848 and then Is_Internal_Name (Chars (Prim_Op))
7849 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
7850 then
7851 Parent_Subp := Alias (Prim_Op);
7853 -- Check if the type has an explicit overriding for this
7854 -- primitive.
7856 Op_Elmt_2 := Next_Elmt (Op_Elmt);
7857 while Present (Op_Elmt_2) loop
7858 if Chars (Node (Op_Elmt_2)) = Chars (Parent_Subp)
7859 and then Type_Conformant (Prim_Op, Node (Op_Elmt_2))
7860 then
7861 Set_DT_Position_Value (Prim_Op,
7862 DT_Position (Parent_Subp));
7863 Set_DT_Position_Value (Node (Op_Elmt_2),
7864 DT_Position (Parent_Subp));
7865 Set_Fixed_Prim (UI_To_Int (DT_Position (Prim_Op)));
7867 goto Next_Primitive;
7868 end if;
7870 Next_Elmt (Op_Elmt_2);
7871 end loop;
7872 end if;
7874 <<Next_Primitive>>
7875 Next_Elmt (Op_Elmt);
7876 end loop;
7877 end Handle_Inherited_Private_Subprograms;
7879 --------------------
7880 -- Set_Fixed_Prim --
7881 --------------------
7883 procedure Set_Fixed_Prim (Pos : Nat) is
7884 begin
7885 pragma Assert (Pos <= Count_Prim);
7886 Fixed_Prim (Pos) := True;
7887 exception
7888 when Constraint_Error =>
7889 raise Program_Error;
7890 end Set_Fixed_Prim;
7892 begin
7893 -- In case of nested packages and public child package it may be
7894 -- necessary a special management on inherited subprograms so that
7895 -- the dispatch table is properly filled.
7897 if Ekind (Scope (Scope (Typ))) = E_Package
7898 and then Scope (Scope (Typ)) /= Standard_Standard
7899 and then ((Is_Derived_Type (Typ) and then not Is_Private_Type (Typ))
7900 or else
7901 (Nkind (Parent (Typ)) = N_Private_Extension_Declaration
7902 and then Is_Generic_Type (Typ)))
7903 and then In_Open_Scopes (Scope (Etype (Typ)))
7904 and then Is_Base_Type (Typ)
7905 then
7906 Handle_Inherited_Private_Subprograms (Typ);
7907 end if;
7909 -- Second stage: Register fixed entries
7911 Nb_Prim := 0;
7912 Prim_Elmt := First_Prim;
7913 while Present (Prim_Elmt) loop
7914 Prim := Node (Prim_Elmt);
7916 -- Predefined primitives have a separate table and all its
7917 -- entries are at predefined fixed positions.
7919 if In_Predef_Prims_DT (Prim) then
7920 if Is_Predefined_Dispatching_Operation (Prim) then
7921 Set_DT_Position_Value (Prim,
7922 Default_Prim_Op_Position (Prim));
7924 else pragma Assert (Present (Alias (Prim)));
7925 Set_DT_Position_Value (Prim,
7926 Default_Prim_Op_Position (Ultimate_Alias (Prim)));
7927 end if;
7929 -- Overriding primitives of ancestor abstract interfaces
7931 elsif Present (Interface_Alias (Prim))
7932 and then Is_Ancestor
7933 (Find_Dispatching_Type (Interface_Alias (Prim)), Typ,
7934 Use_Full_View => True)
7935 then
7936 pragma Assert (DT_Position (Prim) = No_Uint
7937 and then Present (DTC_Entity (Interface_Alias (Prim))));
7939 E := Interface_Alias (Prim);
7940 Set_DT_Position_Value (Prim, DT_Position (E));
7942 pragma Assert
7943 (DT_Position (Alias (Prim)) = No_Uint
7944 or else DT_Position (Alias (Prim)) = DT_Position (E));
7945 Set_DT_Position_Value (Alias (Prim), DT_Position (E));
7946 Set_Fixed_Prim (UI_To_Int (DT_Position (Prim)));
7948 -- Overriding primitives must use the same entry as the overridden
7949 -- primitive. Note that the Alias of the operation is set when the
7950 -- operation is declared by a renaming, in which case it is not
7951 -- overriding. If it renames another primitive it will use the
7952 -- same dispatch table slot, but if it renames an operation in a
7953 -- nested package it's a new primitive and will have its own slot.
7955 elsif not Present (Interface_Alias (Prim))
7956 and then Present (Alias (Prim))
7957 and then Chars (Prim) = Chars (Alias (Prim))
7958 and then Nkind (Unit_Declaration_Node (Prim)) /=
7959 N_Subprogram_Renaming_Declaration
7960 then
7961 declare
7962 Par_Type : constant Entity_Id :=
7963 Find_Dispatching_Type (Alias (Prim));
7965 begin
7966 if Present (Par_Type)
7967 and then Par_Type /= Typ
7968 and then Is_Ancestor (Par_Type, Typ, Use_Full_View => True)
7969 and then Present (DTC_Entity (Alias (Prim)))
7970 then
7971 E := Alias (Prim);
7972 Set_DT_Position_Value (Prim, DT_Position (E));
7974 if not Is_Predefined_Dispatching_Alias (E) then
7975 Set_Fixed_Prim (UI_To_Int (DT_Position (E)));
7976 end if;
7977 end if;
7978 end;
7979 end if;
7981 Next_Elmt (Prim_Elmt);
7982 end loop;
7984 -- Third stage: Fix the position of all the new primitives. Entries
7985 -- associated with primitives covering interfaces are handled in a
7986 -- latter round.
7988 Prim_Elmt := First_Prim;
7989 while Present (Prim_Elmt) loop
7990 Prim := Node (Prim_Elmt);
7992 -- Skip primitives previously set entries
7994 if DT_Position (Prim) /= No_Uint then
7995 null;
7997 -- Primitives covering interface primitives are handled later
7999 elsif Present (Interface_Alias (Prim)) then
8000 null;
8002 else
8003 -- Take the next available position in the DT
8005 loop
8006 Nb_Prim := Nb_Prim + 1;
8007 pragma Assert (Nb_Prim <= Count_Prim);
8008 exit when not Fixed_Prim (Nb_Prim);
8009 end loop;
8011 Set_DT_Position_Value (Prim, UI_From_Int (Nb_Prim));
8012 Set_Fixed_Prim (Nb_Prim);
8013 end if;
8015 Next_Elmt (Prim_Elmt);
8016 end loop;
8017 end;
8019 -- Fourth stage: Complete the decoration of primitives covering
8020 -- interfaces (that is, propagate the DT_Position attribute from
8021 -- the aliased primitive)
8023 Prim_Elmt := First_Prim;
8024 while Present (Prim_Elmt) loop
8025 Prim := Node (Prim_Elmt);
8027 if DT_Position (Prim) = No_Uint
8028 and then Present (Interface_Alias (Prim))
8029 then
8030 pragma Assert (Present (Alias (Prim))
8031 and then Find_Dispatching_Type (Alias (Prim)) = Typ);
8033 -- Check if this entry will be placed in the primary DT
8035 if Is_Ancestor
8036 (Find_Dispatching_Type (Interface_Alias (Prim)), Typ,
8037 Use_Full_View => True)
8038 then
8039 pragma Assert (DT_Position (Alias (Prim)) /= No_Uint);
8040 Set_DT_Position_Value (Prim, DT_Position (Alias (Prim)));
8042 -- Otherwise it will be placed in the secondary DT
8044 else
8045 pragma Assert
8046 (DT_Position (Interface_Alias (Prim)) /= No_Uint);
8047 Set_DT_Position_Value (Prim,
8048 DT_Position (Interface_Alias (Prim)));
8049 end if;
8050 end if;
8052 Next_Elmt (Prim_Elmt);
8053 end loop;
8055 -- Generate listing showing the contents of the dispatch tables. This
8056 -- action is done before some further static checks because in case of
8057 -- critical errors caused by a wrong dispatch table we need to see the
8058 -- contents of such table.
8060 if Debug_Flag_ZZ then
8061 Write_DT (Typ);
8062 end if;
8064 -- Final stage: Ensure that the table is correct plus some further
8065 -- verifications concerning the primitives.
8067 Prim_Elmt := First_Prim;
8068 DT_Length := 0;
8069 while Present (Prim_Elmt) loop
8070 Prim := Node (Prim_Elmt);
8072 -- At this point all the primitives MUST have a position in the
8073 -- dispatch table.
8075 if DT_Position (Prim) = No_Uint then
8076 raise Program_Error;
8077 end if;
8079 -- Calculate real size of the dispatch table
8081 if not In_Predef_Prims_DT (Prim)
8082 and then UI_To_Int (DT_Position (Prim)) > DT_Length
8083 then
8084 DT_Length := UI_To_Int (DT_Position (Prim));
8085 end if;
8087 -- Ensure that the assigned position to non-predefined dispatching
8088 -- operations in the dispatch table is correct.
8090 if not Is_Predefined_Dispatching_Operation (Prim)
8091 and then not Is_Predefined_Dispatching_Alias (Prim)
8092 then
8093 Validate_Position (Prim);
8094 end if;
8096 if Chars (Prim) = Name_Finalize then
8097 Finalized := True;
8098 end if;
8100 if Chars (Prim) = Name_Adjust then
8101 Adjusted := True;
8102 end if;
8104 -- An abstract operation cannot be declared in the private part for a
8105 -- visible abstract type, because it can't be overridden outside this
8106 -- package hierarchy. For explicit declarations this is checked at
8107 -- the point of declaration, but for inherited operations it must be
8108 -- done when building the dispatch table.
8110 -- Ada 2005 (AI-251): Primitives associated with interfaces are
8111 -- excluded from this check because interfaces must be visible in
8112 -- the public and private part (RM 7.3 (7.3/2))
8114 -- We disable this check in Relaxed_RM_Semantics mode, to accommodate
8115 -- legacy Ada code.
8117 if not Relaxed_RM_Semantics
8118 and then Is_Abstract_Type (Typ)
8119 and then Is_Abstract_Subprogram (Prim)
8120 and then Present (Alias (Prim))
8121 and then not Is_Interface
8122 (Find_Dispatching_Type (Ultimate_Alias (Prim)))
8123 and then not Present (Interface_Alias (Prim))
8124 and then Is_Derived_Type (Typ)
8125 and then In_Private_Part (Current_Scope)
8126 and then
8127 List_Containing (Parent (Prim)) =
8128 Private_Declarations (Package_Specification (Current_Scope))
8129 and then Original_View_In_Visible_Part (Typ)
8130 then
8131 -- We exclude Input and Output stream operations because
8132 -- Limited_Controlled inherits useless Input and Output stream
8133 -- operations from Root_Controlled, which can never be overridden.
8135 if not Is_TSS (Prim, TSS_Stream_Input)
8136 and then
8137 not Is_TSS (Prim, TSS_Stream_Output)
8138 then
8139 Error_Msg_NE
8140 ("abstract inherited private operation&" &
8141 " must be overridden (RM 3.9.3(10))",
8142 Parent (Typ), Prim);
8143 end if;
8144 end if;
8146 Next_Elmt (Prim_Elmt);
8147 end loop;
8149 -- Additional check
8151 if Is_Controlled (Typ) then
8152 if not Finalized then
8153 Error_Msg_N
8154 ("controlled type has no explicit Finalize method??", Typ);
8156 elsif not Adjusted then
8157 Error_Msg_N
8158 ("controlled type has no explicit Adjust method??", Typ);
8159 end if;
8160 end if;
8162 -- Set the final size of the Dispatch Table
8164 Set_DT_Entry_Count (The_Tag, UI_From_Int (DT_Length));
8166 -- The derived type must have at least as many components as its parent
8167 -- (for root types Etype points to itself and the test cannot fail).
8169 if DT_Entry_Count (The_Tag) <
8170 DT_Entry_Count (First_Tag_Component (Parent_Typ))
8171 then
8172 raise Program_Error;
8173 end if;
8174 end Set_All_DT_Position;
8176 --------------------------
8177 -- Set_CPP_Constructors --
8178 --------------------------
8180 procedure Set_CPP_Constructors (Typ : Entity_Id) is
8182 function Gen_Parameters_Profile (E : Entity_Id) return List_Id;
8183 -- Duplicate the parameters profile of the imported C++ constructor
8184 -- adding an access to the object as an additional parameter.
8186 ----------------------------
8187 -- Gen_Parameters_Profile --
8188 ----------------------------
8190 function Gen_Parameters_Profile (E : Entity_Id) return List_Id is
8191 Loc : constant Source_Ptr := Sloc (E);
8192 Parms : List_Id;
8193 P : Node_Id;
8195 begin
8196 Parms :=
8197 New_List (
8198 Make_Parameter_Specification (Loc,
8199 Defining_Identifier =>
8200 Make_Defining_Identifier (Loc, Name_uInit),
8201 Parameter_Type => New_Occurrence_Of (Typ, Loc)));
8203 if Present (Parameter_Specifications (Parent (E))) then
8204 P := First (Parameter_Specifications (Parent (E)));
8205 while Present (P) loop
8206 Append_To (Parms,
8207 Make_Parameter_Specification (Loc,
8208 Defining_Identifier =>
8209 Make_Defining_Identifier (Loc,
8210 Chars => Chars (Defining_Identifier (P))),
8211 Parameter_Type => New_Copy_Tree (Parameter_Type (P)),
8212 Expression => New_Copy_Tree (Expression (P))));
8213 Next (P);
8214 end loop;
8215 end if;
8217 return Parms;
8218 end Gen_Parameters_Profile;
8220 -- Local variables
8222 Loc : Source_Ptr;
8223 E : Entity_Id;
8224 Found : Boolean := False;
8225 IP : Entity_Id;
8226 IP_Body : Node_Id;
8227 P : Node_Id;
8228 Parms : List_Id;
8230 Covers_Default_Constructor : Entity_Id := Empty;
8232 -- Start of processing for Set_CPP_Constructor
8234 begin
8235 pragma Assert (Is_CPP_Class (Typ));
8237 -- Look for the constructor entities
8239 E := Next_Entity (Typ);
8240 while Present (E) loop
8241 if Ekind (E) = E_Function
8242 and then Is_Constructor (E)
8243 then
8244 Found := True;
8245 Loc := Sloc (E);
8246 Parms := Gen_Parameters_Profile (E);
8247 IP :=
8248 Make_Defining_Identifier (Loc,
8249 Chars => Make_Init_Proc_Name (Typ));
8251 -- Case 1: Constructor of untagged type
8253 -- If the C++ class has no virtual methods then the matching Ada
8254 -- type is an untagged record type. In such case there is no need
8255 -- to generate a wrapper of the C++ constructor because the _tag
8256 -- component is not available.
8258 if not Is_Tagged_Type (Typ) then
8259 Discard_Node
8260 (Make_Subprogram_Declaration (Loc,
8261 Specification =>
8262 Make_Procedure_Specification (Loc,
8263 Defining_Unit_Name => IP,
8264 Parameter_Specifications => Parms)));
8266 Set_Init_Proc (Typ, IP);
8267 Set_Is_Imported (IP);
8268 Set_Is_Constructor (IP);
8269 Set_Interface_Name (IP, Interface_Name (E));
8270 Set_Convention (IP, Convention_CPP);
8271 Set_Is_Public (IP);
8272 Set_Has_Completion (IP);
8274 -- Case 2: Constructor of a tagged type
8276 -- In this case we generate the IP as a wrapper of the the
8277 -- C++ constructor because IP must also save copy of the _tag
8278 -- generated in the C++ side. The copy of the _tag is used by
8279 -- Build_CPP_Init_Procedure to elaborate derivations of C++ types.
8281 -- Generate:
8282 -- procedure IP (_init : Typ; ...) is
8283 -- procedure ConstructorP (_init : Typ; ...);
8284 -- pragma Import (ConstructorP);
8285 -- begin
8286 -- ConstructorP (_init, ...);
8287 -- if Typ._tag = null then
8288 -- Typ._tag := _init._tag;
8289 -- end if;
8290 -- end IP;
8292 else
8293 declare
8294 Body_Stmts : constant List_Id := New_List;
8295 Constructor_Id : Entity_Id;
8296 Constructor_Decl_Node : Node_Id;
8297 Init_Tags_List : List_Id;
8299 begin
8300 Constructor_Id := Make_Temporary (Loc, 'P');
8302 Constructor_Decl_Node :=
8303 Make_Subprogram_Declaration (Loc,
8304 Make_Procedure_Specification (Loc,
8305 Defining_Unit_Name => Constructor_Id,
8306 Parameter_Specifications => Parms));
8308 Set_Is_Imported (Constructor_Id);
8309 Set_Is_Constructor (Constructor_Id);
8310 Set_Interface_Name (Constructor_Id, Interface_Name (E));
8311 Set_Convention (Constructor_Id, Convention_CPP);
8312 Set_Is_Public (Constructor_Id);
8313 Set_Has_Completion (Constructor_Id);
8315 -- Build the init procedure as a wrapper of this constructor
8317 Parms := Gen_Parameters_Profile (E);
8319 -- Invoke the C++ constructor
8321 declare
8322 Actuals : constant List_Id := New_List;
8324 begin
8325 P := First (Parms);
8326 while Present (P) loop
8327 Append_To (Actuals,
8328 New_Occurrence_Of (Defining_Identifier (P), Loc));
8329 Next (P);
8330 end loop;
8332 Append_To (Body_Stmts,
8333 Make_Procedure_Call_Statement (Loc,
8334 Name => New_Occurrence_Of (Constructor_Id, Loc),
8335 Parameter_Associations => Actuals));
8336 end;
8338 -- Initialize copies of C++ primary and secondary tags
8340 Init_Tags_List := New_List;
8342 declare
8343 Tag_Elmt : Elmt_Id;
8344 Tag_Comp : Node_Id;
8346 begin
8347 Tag_Elmt := First_Elmt (Access_Disp_Table (Typ));
8348 Tag_Comp := First_Tag_Component (Typ);
8350 while Present (Tag_Elmt)
8351 and then Is_Tag (Node (Tag_Elmt))
8352 loop
8353 -- Skip the following assertion with primary tags
8354 -- because Related_Type is not set on primary tag
8355 -- components
8357 pragma Assert
8358 (Tag_Comp = First_Tag_Component (Typ)
8359 or else Related_Type (Node (Tag_Elmt))
8360 = Related_Type (Tag_Comp));
8362 Append_To (Init_Tags_List,
8363 Make_Assignment_Statement (Loc,
8364 Name =>
8365 New_Occurrence_Of (Node (Tag_Elmt), Loc),
8366 Expression =>
8367 Make_Selected_Component (Loc,
8368 Prefix =>
8369 Make_Identifier (Loc, Name_uInit),
8370 Selector_Name =>
8371 New_Occurrence_Of (Tag_Comp, Loc))));
8373 Tag_Comp := Next_Tag_Component (Tag_Comp);
8374 Next_Elmt (Tag_Elmt);
8375 end loop;
8376 end;
8378 Append_To (Body_Stmts,
8379 Make_If_Statement (Loc,
8380 Condition =>
8381 Make_Op_Eq (Loc,
8382 Left_Opnd =>
8383 New_Occurrence_Of
8384 (Node (First_Elmt (Access_Disp_Table (Typ))),
8385 Loc),
8386 Right_Opnd =>
8387 Unchecked_Convert_To (RTE (RE_Tag),
8388 New_Occurrence_Of (RTE (RE_Null_Address), Loc))),
8389 Then_Statements => Init_Tags_List));
8391 IP_Body :=
8392 Make_Subprogram_Body (Loc,
8393 Specification =>
8394 Make_Procedure_Specification (Loc,
8395 Defining_Unit_Name => IP,
8396 Parameter_Specifications => Parms),
8397 Declarations => New_List (Constructor_Decl_Node),
8398 Handled_Statement_Sequence =>
8399 Make_Handled_Sequence_Of_Statements (Loc,
8400 Statements => Body_Stmts,
8401 Exception_Handlers => No_List));
8403 Discard_Node (IP_Body);
8404 Set_Init_Proc (Typ, IP);
8405 end;
8406 end if;
8408 -- If this constructor has parameters and all its parameters have
8409 -- defaults then it covers the default constructor. The semantic
8410 -- analyzer ensures that only one constructor with defaults covers
8411 -- the default constructor.
8413 if Present (Parameter_Specifications (Parent (E)))
8414 and then Needs_No_Actuals (E)
8415 then
8416 Covers_Default_Constructor := IP;
8417 end if;
8418 end if;
8420 Next_Entity (E);
8421 end loop;
8423 -- If there are no constructors, mark the type as abstract since we
8424 -- won't be able to declare objects of that type.
8426 if not Found then
8427 Set_Is_Abstract_Type (Typ);
8428 end if;
8430 -- Handle constructor that has all its parameters with defaults and
8431 -- hence it covers the default constructor. We generate a wrapper IP
8432 -- which calls the covering constructor.
8434 if Present (Covers_Default_Constructor) then
8435 declare
8436 Body_Stmts : List_Id;
8438 begin
8439 Loc := Sloc (Covers_Default_Constructor);
8441 Body_Stmts := New_List (
8442 Make_Procedure_Call_Statement (Loc,
8443 Name =>
8444 New_Occurrence_Of (Covers_Default_Constructor, Loc),
8445 Parameter_Associations => New_List (
8446 Make_Identifier (Loc, Name_uInit))));
8448 IP := Make_Defining_Identifier (Loc, Make_Init_Proc_Name (Typ));
8450 IP_Body :=
8451 Make_Subprogram_Body (Loc,
8452 Specification =>
8453 Make_Procedure_Specification (Loc,
8454 Defining_Unit_Name => IP,
8455 Parameter_Specifications => New_List (
8456 Make_Parameter_Specification (Loc,
8457 Defining_Identifier =>
8458 Make_Defining_Identifier (Loc, Name_uInit),
8459 Parameter_Type => New_Occurrence_Of (Typ, Loc)))),
8461 Declarations => No_List,
8463 Handled_Statement_Sequence =>
8464 Make_Handled_Sequence_Of_Statements (Loc,
8465 Statements => Body_Stmts,
8466 Exception_Handlers => No_List));
8468 Discard_Node (IP_Body);
8469 Set_Init_Proc (Typ, IP);
8470 end;
8471 end if;
8473 -- If the CPP type has constructors then it must import also the default
8474 -- C++ constructor. It is required for default initialization of objects
8475 -- of the type. It is also required to elaborate objects of Ada types
8476 -- that are defined as derivations of this CPP type.
8478 if Has_CPP_Constructors (Typ)
8479 and then No (Init_Proc (Typ))
8480 then
8481 Error_Msg_N ("??default constructor must be imported from C++", Typ);
8482 end if;
8483 end Set_CPP_Constructors;
8485 ---------------------------
8486 -- Set_DT_Position_Value --
8487 ---------------------------
8489 procedure Set_DT_Position_Value (Prim : Entity_Id; Value : Uint) is
8490 begin
8491 Set_DT_Position (Prim, Value);
8493 -- Propagate the value to the wrapped subprogram (if one is present)
8495 if Ekind_In (Prim, E_Function, E_Procedure)
8496 and then Is_Primitive_Wrapper (Prim)
8497 and then Present (Wrapped_Entity (Prim))
8498 and then Is_Dispatching_Operation (Wrapped_Entity (Prim))
8499 then
8500 Set_DT_Position (Wrapped_Entity (Prim), Value);
8501 end if;
8502 end Set_DT_Position_Value;
8504 --------------------------
8505 -- Set_DTC_Entity_Value --
8506 --------------------------
8508 procedure Set_DTC_Entity_Value
8509 (Tagged_Type : Entity_Id;
8510 Prim : Entity_Id)
8512 begin
8513 if Present (Interface_Alias (Prim))
8514 and then Is_Interface
8515 (Find_Dispatching_Type (Interface_Alias (Prim)))
8516 then
8517 Set_DTC_Entity (Prim,
8518 Find_Interface_Tag
8519 (T => Tagged_Type,
8520 Iface => Find_Dispatching_Type (Interface_Alias (Prim))));
8521 else
8522 Set_DTC_Entity (Prim,
8523 First_Tag_Component (Tagged_Type));
8524 end if;
8526 -- Propagate the value to the wrapped subprogram (if one is present)
8528 if Ekind_In (Prim, E_Function, E_Procedure)
8529 and then Is_Primitive_Wrapper (Prim)
8530 and then Present (Wrapped_Entity (Prim))
8531 and then Is_Dispatching_Operation (Wrapped_Entity (Prim))
8532 then
8533 Set_DTC_Entity (Wrapped_Entity (Prim), DTC_Entity (Prim));
8534 end if;
8535 end Set_DTC_Entity_Value;
8537 -----------------
8538 -- Tagged_Kind --
8539 -----------------
8541 function Tagged_Kind (T : Entity_Id) return Node_Id is
8542 Conc_Typ : Entity_Id;
8543 Loc : constant Source_Ptr := Sloc (T);
8545 begin
8546 pragma Assert
8547 (Is_Tagged_Type (T) and then RTE_Available (RE_Tagged_Kind));
8549 -- Abstract kinds
8551 if Is_Abstract_Type (T) then
8552 if Is_Limited_Record (T) then
8553 return New_Occurrence_Of
8554 (RTE (RE_TK_Abstract_Limited_Tagged), Loc);
8555 else
8556 return New_Occurrence_Of
8557 (RTE (RE_TK_Abstract_Tagged), Loc);
8558 end if;
8560 -- Concurrent kinds
8562 elsif Is_Concurrent_Record_Type (T) then
8563 Conc_Typ := Corresponding_Concurrent_Type (T);
8565 if Present (Full_View (Conc_Typ)) then
8566 Conc_Typ := Full_View (Conc_Typ);
8567 end if;
8569 if Ekind (Conc_Typ) = E_Protected_Type then
8570 return New_Occurrence_Of (RTE (RE_TK_Protected), Loc);
8571 else
8572 pragma Assert (Ekind (Conc_Typ) = E_Task_Type);
8573 return New_Occurrence_Of (RTE (RE_TK_Task), Loc);
8574 end if;
8576 -- Regular tagged kinds
8578 else
8579 if Is_Limited_Record (T) then
8580 return New_Occurrence_Of (RTE (RE_TK_Limited_Tagged), Loc);
8581 else
8582 return New_Occurrence_Of (RTE (RE_TK_Tagged), Loc);
8583 end if;
8584 end if;
8585 end Tagged_Kind;
8587 --------------
8588 -- Write_DT --
8589 --------------
8591 procedure Write_DT (Typ : Entity_Id) is
8592 Elmt : Elmt_Id;
8593 Prim : Node_Id;
8595 begin
8596 -- Protect this procedure against wrong usage. Required because it will
8597 -- be used directly from GDB
8599 if not (Typ <= Last_Node_Id)
8600 or else not Is_Tagged_Type (Typ)
8601 then
8602 Write_Str ("wrong usage: Write_DT must be used with tagged types");
8603 Write_Eol;
8604 return;
8605 end if;
8607 Write_Int (Int (Typ));
8608 Write_Str (": ");
8609 Write_Name (Chars (Typ));
8611 if Is_Interface (Typ) then
8612 Write_Str (" is interface");
8613 end if;
8615 Write_Eol;
8617 Elmt := First_Elmt (Primitive_Operations (Typ));
8618 while Present (Elmt) loop
8619 Prim := Node (Elmt);
8620 Write_Str (" - ");
8622 -- Indicate if this primitive will be allocated in the primary
8623 -- dispatch table or in a secondary dispatch table associated
8624 -- with an abstract interface type
8626 if Present (DTC_Entity (Prim)) then
8627 if Etype (DTC_Entity (Prim)) = RTE (RE_Tag) then
8628 Write_Str ("[P] ");
8629 else
8630 Write_Str ("[s] ");
8631 end if;
8632 end if;
8634 -- Output the node of this primitive operation and its name
8636 Write_Int (Int (Prim));
8637 Write_Str (": ");
8639 if Is_Predefined_Dispatching_Operation (Prim) then
8640 Write_Str ("(predefined) ");
8641 end if;
8643 -- Prefix the name of the primitive with its corresponding tagged
8644 -- type to facilitate seeing inherited primitives.
8646 if Present (Alias (Prim)) then
8647 Write_Name
8648 (Chars (Find_Dispatching_Type (Ultimate_Alias (Prim))));
8649 else
8650 Write_Name (Chars (Typ));
8651 end if;
8653 Write_Str (".");
8654 Write_Name (Chars (Prim));
8656 -- Indicate if this primitive has an aliased primitive
8658 if Present (Alias (Prim)) then
8659 Write_Str (" (alias = ");
8660 Write_Int (Int (Alias (Prim)));
8662 -- If the DTC_Entity attribute is already set we can also output
8663 -- the name of the interface covered by this primitive (if any).
8665 if Ekind_In (Alias (Prim), E_Function, E_Procedure)
8666 and then Present (DTC_Entity (Alias (Prim)))
8667 and then Is_Interface (Scope (DTC_Entity (Alias (Prim))))
8668 then
8669 Write_Str (" from interface ");
8670 Write_Name (Chars (Scope (DTC_Entity (Alias (Prim)))));
8671 end if;
8673 if Present (Interface_Alias (Prim)) then
8674 Write_Str (", AI_Alias of ");
8676 if Is_Null_Interface_Primitive (Interface_Alias (Prim)) then
8677 Write_Str ("null primitive ");
8678 end if;
8680 Write_Name
8681 (Chars (Find_Dispatching_Type (Interface_Alias (Prim))));
8682 Write_Char (':');
8683 Write_Int (Int (Interface_Alias (Prim)));
8684 end if;
8686 Write_Str (")");
8687 end if;
8689 -- Display the final position of this primitive in its associated
8690 -- (primary or secondary) dispatch table.
8692 if Present (DTC_Entity (Prim))
8693 and then DT_Position (Prim) /= No_Uint
8694 then
8695 Write_Str (" at #");
8696 Write_Int (UI_To_Int (DT_Position (Prim)));
8697 end if;
8699 if Is_Abstract_Subprogram (Prim) then
8700 Write_Str (" is abstract;");
8702 -- Check if this is a null primitive
8704 elsif Comes_From_Source (Prim)
8705 and then Ekind (Prim) = E_Procedure
8706 and then Null_Present (Parent (Prim))
8707 then
8708 Write_Str (" is null;");
8709 end if;
8711 if Is_Eliminated (Ultimate_Alias (Prim)) then
8712 Write_Str (" (eliminated)");
8713 end if;
8715 if Is_Imported (Prim)
8716 and then Convention (Prim) = Convention_CPP
8717 then
8718 Write_Str (" (C++)");
8719 end if;
8721 Write_Eol;
8723 Next_Elmt (Elmt);
8724 end loop;
8725 end Write_DT;
8727 end Exp_Disp;