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* arm.c (FL_WBUF): Define.
[official-gcc.git] / gcc / ada / exp_util.adb
blob4868dc1286e8f83ccc1cc9271f7ed0c2187cd0c8
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- E X P _ U T I L --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2005, 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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
21 -- --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 -- --
25 ------------------------------------------------------------------------------
26
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Aggr; use Exp_Aggr;
33 with Exp_Ch7; use Exp_Ch7;
34 with Exp_Ch11; use Exp_Ch11;
35 with Exp_Tss; use Exp_Tss;
36 with Hostparm; use Hostparm;
37 with Inline; use Inline;
38 with Itypes; use Itypes;
39 with Lib; use Lib;
40 with Namet; use Namet;
41 with Nlists; use Nlists;
42 with Nmake; use Nmake;
43 with Opt; use Opt;
44 with Restrict; use Restrict;
45 with Rident; use Rident;
46 with Sem; use Sem;
47 with Sem_Ch8; use Sem_Ch8;
48 with Sem_Eval; use Sem_Eval;
49 with Sem_Res; use Sem_Res;
50 with Sem_Util; use Sem_Util;
51 with Sinfo; use Sinfo;
52 with Snames; use Snames;
53 with Stand; use Stand;
54 with Stringt; use Stringt;
55 with Targparm; use Targparm;
56 with Tbuild; use Tbuild;
57 with Ttypes; use Ttypes;
58 with Uintp; use Uintp;
59 with Urealp; use Urealp;
60 with Validsw; use Validsw;
61
62 package body Exp_Util is
63
64 -----------------------
65 -- Local Subprograms --
66 -----------------------
67
68 function Build_Task_Array_Image
69 (Loc : Source_Ptr;
70 Id_Ref : Node_Id;
71 A_Type : Entity_Id;
72 Dyn : Boolean := False) return Node_Id;
73 -- Build function to generate the image string for a task that is an
74 -- array component, concatenating the images of each index. To avoid
75 -- storage leaks, the string is built with successive slice assignments.
76 -- The flag Dyn indicates whether this is called for the initialization
77 -- procedure of an array of tasks, or for the name of a dynamically
78 -- created task that is assigned to an indexed component.
79
80 function Build_Task_Image_Function
81 (Loc : Source_Ptr;
82 Decls : List_Id;
83 Stats : List_Id;
84 Res : Entity_Id) return Node_Id;
85 -- Common processing for Task_Array_Image and Task_Record_Image.
86 -- Build function body that computes image.
87
88 procedure Build_Task_Image_Prefix
89 (Loc : Source_Ptr;
90 Len : out Entity_Id;
91 Res : out Entity_Id;
92 Pos : out Entity_Id;
93 Prefix : Entity_Id;
94 Sum : Node_Id;
95 Decls : in out List_Id;
96 Stats : in out List_Id);
97 -- Common processing for Task_Array_Image and Task_Record_Image.
98 -- Create local variables and assign prefix of name to result string.
99
100 function Build_Task_Record_Image
101 (Loc : Source_Ptr;
102 Id_Ref : Node_Id;
103 Dyn : Boolean := False) return Node_Id;
104 -- Build function to generate the image string for a task that is a
105 -- record component. Concatenate name of variable with that of selector.
106 -- The flag Dyn indicates whether this is called for the initialization
107 -- procedure of record with task components, or for a dynamically
108 -- created task that is assigned to a selected component.
109
110 function Make_CW_Equivalent_Type
111 (T : Entity_Id;
112 E : Node_Id) return Entity_Id;
113 -- T is a class-wide type entity, E is the initial expression node that
114 -- constrains T in case such as: " X: T := E" or "new T'(E)"
115 -- This function returns the entity of the Equivalent type and inserts
116 -- on the fly the necessary declaration such as:
117 --
118 -- type anon is record
119 -- _parent : Root_Type (T); constrained with E discriminants (if any)
120 -- Extension : String (1 .. expr to match size of E);
121 -- end record;
122 --
123 -- This record is compatible with any object of the class of T thanks
124 -- to the first field and has the same size as E thanks to the second.
125
126 function Make_Literal_Range
127 (Loc : Source_Ptr;
128 Literal_Typ : Entity_Id) return Node_Id;
129 -- Produce a Range node whose bounds are:
130 -- Low_Bound (Literal_Type) ..
131 -- Low_Bound (Literal_Type) + Length (Literal_Typ) - 1
132 -- this is used for expanding declarations like X : String := "sdfgdfg";
133
134 function New_Class_Wide_Subtype
135 (CW_Typ : Entity_Id;
136 N : Node_Id) return Entity_Id;
137 -- Create an implicit subtype of CW_Typ attached to node N
138
139 ----------------------
140 -- Adjust_Condition --
141 ----------------------
142
143 procedure Adjust_Condition (N : Node_Id) is
144 begin
145 if No (N) then
146 return;
147 end if;
148
149 declare
150 Loc : constant Source_Ptr := Sloc (N);
151 T : constant Entity_Id := Etype (N);
152 Ti : Entity_Id;
153
154 begin
155 -- For now, we simply ignore a call where the argument has no
156 -- type (probably case of unanalyzed condition), or has a type
157 -- that is not Boolean. This is because this is a pretty marginal
158 -- piece of functionality, and violations of these rules are
159 -- likely to be truly marginal (how much code uses Fortran Logical
160 -- as the barrier to a protected entry?) and we do not want to
161 -- blow up existing programs. We can change this to an assertion
162 -- after 3.12a is released ???
163
164 if No (T) or else not Is_Boolean_Type (T) then
165 return;
166 end if;
167
168 -- Apply validity checking if needed
169
170 if Validity_Checks_On and Validity_Check_Tests then
171 Ensure_Valid (N);
172 end if;
173
174 -- Immediate return if standard boolean, the most common case,
175 -- where nothing needs to be done.
176
177 if Base_Type (T) = Standard_Boolean then
178 return;
179 end if;
180
181 -- Case of zero/non-zero semantics or non-standard enumeration
182 -- representation. In each case, we rewrite the node as:
183
184 -- ityp!(N) /= False'Enum_Rep
185
186 -- where ityp is an integer type with large enough size to hold
187 -- any value of type T.
188
189 if Nonzero_Is_True (T) or else Has_Non_Standard_Rep (T) then
190 if Esize (T) <= Esize (Standard_Integer) then
191 Ti := Standard_Integer;
192 else
193 Ti := Standard_Long_Long_Integer;
194 end if;
195
196 Rewrite (N,
197 Make_Op_Ne (Loc,
198 Left_Opnd => Unchecked_Convert_To (Ti, N),
199 Right_Opnd =>
200 Make_Attribute_Reference (Loc,
201 Attribute_Name => Name_Enum_Rep,
202 Prefix =>
203 New_Occurrence_Of (First_Literal (T), Loc))));
204 Analyze_And_Resolve (N, Standard_Boolean);
205
206 else
207 Rewrite (N, Convert_To (Standard_Boolean, N));
208 Analyze_And_Resolve (N, Standard_Boolean);
209 end if;
210 end;
211 end Adjust_Condition;
212
213 ------------------------
214 -- Adjust_Result_Type --
215 ------------------------
216
217 procedure Adjust_Result_Type (N : Node_Id; T : Entity_Id) is
218 begin
219 -- Ignore call if current type is not Standard.Boolean
220
221 if Etype (N) /= Standard_Boolean then
222 return;
223 end if;
224
225 -- If result is already of correct type, nothing to do. Note that
226 -- this will get the most common case where everything has a type
227 -- of Standard.Boolean.
228
229 if Base_Type (T) = Standard_Boolean then
230 return;
231
232 else
233 declare
234 KP : constant Node_Kind := Nkind (Parent (N));
235
236 begin
237 -- If result is to be used as a Condition in the syntax, no need
238 -- to convert it back, since if it was changed to Standard.Boolean
239 -- using Adjust_Condition, that is just fine for this usage.
240
241 if KP in N_Raise_xxx_Error or else KP in N_Has_Condition then
242 return;
243
244 -- If result is an operand of another logical operation, no need
245 -- to reset its type, since Standard.Boolean is just fine, and
246 -- such operations always do Adjust_Condition on their operands.
247
248 elsif KP in N_Op_Boolean
249 or else KP = N_And_Then
250 or else KP = N_Or_Else
251 or else KP = N_Op_Not
252 then
253 return;
254
255 -- Otherwise we perform a conversion from the current type,
256 -- which must be Standard.Boolean, to the desired type.
257
258 else
259 Set_Analyzed (N);
260 Rewrite (N, Convert_To (T, N));
261 Analyze_And_Resolve (N, T);
262 end if;
263 end;
264 end if;
265 end Adjust_Result_Type;
266
267 --------------------------
268 -- Append_Freeze_Action --
269 --------------------------
270
271 procedure Append_Freeze_Action (T : Entity_Id; N : Node_Id) is
272 Fnode : Node_Id := Freeze_Node (T);
273
274 begin
275 Ensure_Freeze_Node (T);
276 Fnode := Freeze_Node (T);
277
278 if not Present (Actions (Fnode)) then
279 Set_Actions (Fnode, New_List);
280 end if;
281
282 Append (N, Actions (Fnode));
283 end Append_Freeze_Action;
284
285 ---------------------------
286 -- Append_Freeze_Actions --
287 ---------------------------
288
289 procedure Append_Freeze_Actions (T : Entity_Id; L : List_Id) is
290 Fnode : constant Node_Id := Freeze_Node (T);
291
292 begin
293 if No (L) then
294 return;
295
296 else
297 if No (Actions (Fnode)) then
298 Set_Actions (Fnode, L);
299
300 else
301 Append_List (L, Actions (Fnode));
302 end if;
303
304 end if;
305 end Append_Freeze_Actions;
306
307 ------------------------
308 -- Build_Runtime_Call --
309 ------------------------
310
311 function Build_Runtime_Call (Loc : Source_Ptr; RE : RE_Id) return Node_Id is
312 begin
313 -- If entity is not available, we can skip making the call (this avoids
314 -- junk duplicated error messages in a number of cases).
315
316 if not RTE_Available (RE) then
317 return Make_Null_Statement (Loc);
318 else
319 return
320 Make_Procedure_Call_Statement (Loc,
321 Name => New_Reference_To (RTE (RE), Loc));
322 end if;
323 end Build_Runtime_Call;
324
325 ----------------------------
326 -- Build_Task_Array_Image --
327 ----------------------------
328
329 -- This function generates the body for a function that constructs the
330 -- image string for a task that is an array component. The function is
331 -- local to the init proc for the array type, and is called for each one
332 -- of the components. The constructed image has the form of an indexed
333 -- component, whose prefix is the outer variable of the array type.
334 -- The n-dimensional array type has known indices Index, Index2...
335 -- Id_Ref is an indexed component form created by the enclosing init proc.
336 -- Its successive indices are Val1, Val2,.. which are the loop variables
337 -- in the loops that call the individual task init proc on each component.
338
339 -- The generated function has the following structure:
340
341 -- function F return String is
342 -- Pref : string renames Task_Name;
343 -- T1 : String := Index1'Image (Val1);
344 -- ...
345 -- Tn : String := indexn'image (Valn);
346 -- Len : Integer := T1'Length + ... + Tn'Length + n + 1;
347 -- -- Len includes commas and the end parentheses.
348 -- Res : String (1..Len);
349 -- Pos : Integer := Pref'Length;
350 --
351 -- begin
352 -- Res (1 .. Pos) := Pref;
353 -- Pos := Pos + 1;
354 -- Res (Pos) := '(';
355 -- Pos := Pos + 1;
356 -- Res (Pos .. Pos + T1'Length - 1) := T1;
357 -- Pos := Pos + T1'Length;
358 -- Res (Pos) := '.';
359 -- Pos := Pos + 1;
360 -- ...
361 -- Res (Pos .. Pos + Tn'Length - 1) := Tn;
362 -- Res (Len) := ')';
363 --
364 -- return Res;
365 -- end F;
366 --
367 -- Needless to say, multidimensional arrays of tasks are rare enough
368 -- that the bulkiness of this code is not really a concern.
369
370 function Build_Task_Array_Image
371 (Loc : Source_Ptr;
372 Id_Ref : Node_Id;
373 A_Type : Entity_Id;
374 Dyn : Boolean := False) return Node_Id
375 is
376 Dims : constant Nat := Number_Dimensions (A_Type);
377 -- Number of dimensions for array of tasks
378
379 Temps : array (1 .. Dims) of Entity_Id;
380 -- Array of temporaries to hold string for each index
381
382 Indx : Node_Id;
383 -- Index expression
384
385 Len : Entity_Id;
386 -- Total length of generated name
387
388 Pos : Entity_Id;
389 -- Running index for substring assignments
390
391 Pref : Entity_Id;
392 -- Name of enclosing variable, prefix of resulting name
393
394 Res : Entity_Id;
395 -- String to hold result
396
397 Val : Node_Id;
398 -- Value of successive indices
399
400 Sum : Node_Id;
401 -- Expression to compute total size of string
402
403 T : Entity_Id;
404 -- Entity for name at one index position
405
406 Decls : List_Id := New_List;
407 Stats : List_Id := New_List;
408
409 begin
410 Pref := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
411
412 -- For a dynamic task, the name comes from the target variable.
413 -- For a static one it is a formal of the enclosing init proc.
414
415 if Dyn then
416 Get_Name_String (Chars (Entity (Prefix (Id_Ref))));
417 Append_To (Decls,
418 Make_Object_Declaration (Loc,
419 Defining_Identifier => Pref,
420 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
421 Expression =>
422 Make_String_Literal (Loc,
423 Strval => String_From_Name_Buffer)));
424
425 else
426 Append_To (Decls,
427 Make_Object_Renaming_Declaration (Loc,
428 Defining_Identifier => Pref,
429 Subtype_Mark => New_Occurrence_Of (Standard_String, Loc),
430 Name => Make_Identifier (Loc, Name_uTask_Name)));
431 end if;
432
433 Indx := First_Index (A_Type);
434 Val := First (Expressions (Id_Ref));
435
436 for J in 1 .. Dims loop
437 T := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
438 Temps (J) := T;
439
440 Append_To (Decls,
441 Make_Object_Declaration (Loc,
442 Defining_Identifier => T,
443 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
444 Expression =>
445 Make_Attribute_Reference (Loc,
446 Attribute_Name => Name_Image,
447 Prefix =>
448 New_Occurrence_Of (Etype (Indx), Loc),
449 Expressions => New_List (
450 New_Copy_Tree (Val)))));
451
452 Next_Index (Indx);
453 Next (Val);
454 end loop;
455
456 Sum := Make_Integer_Literal (Loc, Dims + 1);
457
458 Sum :=
459 Make_Op_Add (Loc,
460 Left_Opnd => Sum,
461 Right_Opnd =>
462 Make_Attribute_Reference (Loc,
463 Attribute_Name => Name_Length,
464 Prefix =>
465 New_Occurrence_Of (Pref, Loc),
466 Expressions => New_List (Make_Integer_Literal (Loc, 1))));
467
468 for J in 1 .. Dims loop
469 Sum :=
470 Make_Op_Add (Loc,
471 Left_Opnd => Sum,
472 Right_Opnd =>
473 Make_Attribute_Reference (Loc,
474 Attribute_Name => Name_Length,
475 Prefix =>
476 New_Occurrence_Of (Temps (J), Loc),
477 Expressions => New_List (Make_Integer_Literal (Loc, 1))));
478 end loop;
479
480 Build_Task_Image_Prefix (Loc, Len, Res, Pos, Pref, Sum, Decls, Stats);
481
482 Set_Character_Literal_Name (Char_Code (Character'Pos ('(')));
483
484 Append_To (Stats,
485 Make_Assignment_Statement (Loc,
486 Name => Make_Indexed_Component (Loc,
487 Prefix => New_Occurrence_Of (Res, Loc),
488 Expressions => New_List (New_Occurrence_Of (Pos, Loc))),
489 Expression =>
490 Make_Character_Literal (Loc,
491 Chars => Name_Find,
492 Char_Literal_Value =>
493 UI_From_Int (Character'Pos ('(')))));
494
495 Append_To (Stats,
496 Make_Assignment_Statement (Loc,
497 Name => New_Occurrence_Of (Pos, Loc),
498 Expression =>
499 Make_Op_Add (Loc,
500 Left_Opnd => New_Occurrence_Of (Pos, Loc),
501 Right_Opnd => Make_Integer_Literal (Loc, 1))));
502
503 for J in 1 .. Dims loop
504
505 Append_To (Stats,
506 Make_Assignment_Statement (Loc,
507 Name => Make_Slice (Loc,
508 Prefix => New_Occurrence_Of (Res, Loc),
509 Discrete_Range =>
510 Make_Range (Loc,
511 Low_Bound => New_Occurrence_Of (Pos, Loc),
512 High_Bound => Make_Op_Subtract (Loc,
513 Left_Opnd =>
514 Make_Op_Add (Loc,
515 Left_Opnd => New_Occurrence_Of (Pos, Loc),
516 Right_Opnd =>
517 Make_Attribute_Reference (Loc,
518 Attribute_Name => Name_Length,
519 Prefix =>
520 New_Occurrence_Of (Temps (J), Loc),
521 Expressions =>
522 New_List (Make_Integer_Literal (Loc, 1)))),
523 Right_Opnd => Make_Integer_Literal (Loc, 1)))),
524
525 Expression => New_Occurrence_Of (Temps (J), Loc)));
526
527 if J < Dims then
528 Append_To (Stats,
529 Make_Assignment_Statement (Loc,
530 Name => New_Occurrence_Of (Pos, Loc),
531 Expression =>
532 Make_Op_Add (Loc,
533 Left_Opnd => New_Occurrence_Of (Pos, Loc),
534 Right_Opnd =>
535 Make_Attribute_Reference (Loc,
536 Attribute_Name => Name_Length,
537 Prefix => New_Occurrence_Of (Temps (J), Loc),
538 Expressions =>
539 New_List (Make_Integer_Literal (Loc, 1))))));
540
541 Set_Character_Literal_Name (Char_Code (Character'Pos (',')));
542
543 Append_To (Stats,
544 Make_Assignment_Statement (Loc,
545 Name => Make_Indexed_Component (Loc,
546 Prefix => New_Occurrence_Of (Res, Loc),
547 Expressions => New_List (New_Occurrence_Of (Pos, Loc))),
548 Expression =>
549 Make_Character_Literal (Loc,
550 Chars => Name_Find,
551 Char_Literal_Value =>
552 UI_From_Int (Character'Pos (',')))));
553
554 Append_To (Stats,
555 Make_Assignment_Statement (Loc,
556 Name => New_Occurrence_Of (Pos, Loc),
557 Expression =>
558 Make_Op_Add (Loc,
559 Left_Opnd => New_Occurrence_Of (Pos, Loc),
560 Right_Opnd => Make_Integer_Literal (Loc, 1))));
561 end if;
562 end loop;
563
564 Set_Character_Literal_Name (Char_Code (Character'Pos (')')));
565
566 Append_To (Stats,
567 Make_Assignment_Statement (Loc,
568 Name => Make_Indexed_Component (Loc,
569 Prefix => New_Occurrence_Of (Res, Loc),
570 Expressions => New_List (New_Occurrence_Of (Len, Loc))),
571 Expression =>
572 Make_Character_Literal (Loc,
573 Chars => Name_Find,
574 Char_Literal_Value =>
575 UI_From_Int (Character'Pos (')')))));
576 return Build_Task_Image_Function (Loc, Decls, Stats, Res);
577 end Build_Task_Array_Image;
578
579 ----------------------------
580 -- Build_Task_Image_Decls --
581 ----------------------------
582
583 function Build_Task_Image_Decls
584 (Loc : Source_Ptr;
585 Id_Ref : Node_Id;
586 A_Type : Entity_Id) return List_Id
587 is
588 Decls : constant List_Id := New_List;
589 T_Id : Entity_Id := Empty;
590 Decl : Node_Id;
591 Expr : Node_Id := Empty;
592 Fun : Node_Id := Empty;
593 Is_Dyn : constant Boolean :=
594 Nkind (Parent (Id_Ref)) = N_Assignment_Statement
595 and then
596 Nkind (Expression (Parent (Id_Ref))) = N_Allocator;
597
598 begin
599 -- If Discard_Names or No_Implicit_Heap_Allocations are in effect,
600 -- generate a dummy declaration only.
601
602 if Restriction_Active (No_Implicit_Heap_Allocations)
603 or else Global_Discard_Names
604 then
605 T_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
606 Name_Len := 0;
607
608 return
609 New_List (
610 Make_Object_Declaration (Loc,
611 Defining_Identifier => T_Id,
612 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
613 Expression =>
614 Make_String_Literal (Loc,
615 Strval => String_From_Name_Buffer)));
616
617 else
618 if Nkind (Id_Ref) = N_Identifier
619 or else Nkind (Id_Ref) = N_Defining_Identifier
620 then
621 -- For a simple variable, the image of the task is built from
622 -- the name of the variable. To avoid possible conflict with
623 -- the anonymous type created for a single protected object,
624 -- add a numeric suffix.
625
626 T_Id :=
627 Make_Defining_Identifier (Loc,
628 New_External_Name (Chars (Id_Ref), 'T', 1));
629
630 Get_Name_String (Chars (Id_Ref));
631
632 Expr :=
633 Make_String_Literal (Loc,
634 Strval => String_From_Name_Buffer);
635
636 elsif Nkind (Id_Ref) = N_Selected_Component then
637 T_Id :=
638 Make_Defining_Identifier (Loc,
639 New_External_Name (Chars (Selector_Name (Id_Ref)), 'T'));
640 Fun := Build_Task_Record_Image (Loc, Id_Ref, Is_Dyn);
641
642 elsif Nkind (Id_Ref) = N_Indexed_Component then
643 T_Id :=
644 Make_Defining_Identifier (Loc,
645 New_External_Name (Chars (A_Type), 'N'));
646
647 Fun := Build_Task_Array_Image (Loc, Id_Ref, A_Type, Is_Dyn);
648 end if;
649 end if;
650
651 if Present (Fun) then
652 Append (Fun, Decls);
653 Expr := Make_Function_Call (Loc,
654 Name => New_Occurrence_Of (Defining_Entity (Fun), Loc));
655 end if;
656
657 Decl := Make_Object_Declaration (Loc,
658 Defining_Identifier => T_Id,
659 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
660 Constant_Present => True,
661 Expression => Expr);
662
663 Append (Decl, Decls);
664 return Decls;
665 end Build_Task_Image_Decls;
666
667 -------------------------------
668 -- Build_Task_Image_Function --
669 -------------------------------
670
671 function Build_Task_Image_Function
672 (Loc : Source_Ptr;
673 Decls : List_Id;
674 Stats : List_Id;
675 Res : Entity_Id) return Node_Id
676 is
677 Spec : Node_Id;
678
679 begin
680 Append_To (Stats,
681 Make_Return_Statement (Loc,
682 Expression => New_Occurrence_Of (Res, Loc)));
683
684 Spec := Make_Function_Specification (Loc,
685 Defining_Unit_Name =>
686 Make_Defining_Identifier (Loc, New_Internal_Name ('F')),
687 Subtype_Mark => New_Occurrence_Of (Standard_String, Loc));
688
689 -- Calls to 'Image use the secondary stack, which must be cleaned
690 -- up after the task name is built.
691
692 Set_Uses_Sec_Stack (Defining_Unit_Name (Spec));
693
694 return Make_Subprogram_Body (Loc,
695 Specification => Spec,
696 Declarations => Decls,
697 Handled_Statement_Sequence =>
698 Make_Handled_Sequence_Of_Statements (Loc, Statements => Stats));
699 end Build_Task_Image_Function;
700
701 -----------------------------
702 -- Build_Task_Image_Prefix --
703 -----------------------------
704
705 procedure Build_Task_Image_Prefix
706 (Loc : Source_Ptr;
707 Len : out Entity_Id;
708 Res : out Entity_Id;
709 Pos : out Entity_Id;
710 Prefix : Entity_Id;
711 Sum : Node_Id;
712 Decls : in out List_Id;
713 Stats : in out List_Id)
714 is
715 begin
716 Len := Make_Defining_Identifier (Loc, New_Internal_Name ('L'));
717
718 Append_To (Decls,
719 Make_Object_Declaration (Loc,
720 Defining_Identifier => Len,
721 Object_Definition => New_Occurrence_Of (Standard_Integer, Loc),
722 Expression => Sum));
723
724 Res := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
725
726 Append_To (Decls,
727 Make_Object_Declaration (Loc,
728 Defining_Identifier => Res,
729 Object_Definition =>
730 Make_Subtype_Indication (Loc,
731 Subtype_Mark => New_Occurrence_Of (Standard_String, Loc),
732 Constraint =>
733 Make_Index_Or_Discriminant_Constraint (Loc,
734 Constraints =>
735 New_List (
736 Make_Range (Loc,
737 Low_Bound => Make_Integer_Literal (Loc, 1),
738 High_Bound => New_Occurrence_Of (Len, Loc)))))));
739
740 Pos := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
741
742 Append_To (Decls,
743 Make_Object_Declaration (Loc,
744 Defining_Identifier => Pos,
745 Object_Definition => New_Occurrence_Of (Standard_Integer, Loc)));
746
747 -- Pos := Prefix'Length;
748
749 Append_To (Stats,
750 Make_Assignment_Statement (Loc,
751 Name => New_Occurrence_Of (Pos, Loc),
752 Expression =>
753 Make_Attribute_Reference (Loc,
754 Attribute_Name => Name_Length,
755 Prefix => New_Occurrence_Of (Prefix, Loc),
756 Expressions =>
757 New_List (Make_Integer_Literal (Loc, 1)))));
758
759 -- Res (1 .. Pos) := Prefix;
760
761 Append_To (Stats,
762 Make_Assignment_Statement (Loc,
763 Name => Make_Slice (Loc,
764 Prefix => New_Occurrence_Of (Res, Loc),
765 Discrete_Range =>
766 Make_Range (Loc,
767 Low_Bound => Make_Integer_Literal (Loc, 1),
768 High_Bound => New_Occurrence_Of (Pos, Loc))),
769
770 Expression => New_Occurrence_Of (Prefix, Loc)));
771
772 Append_To (Stats,
773 Make_Assignment_Statement (Loc,
774 Name => New_Occurrence_Of (Pos, Loc),
775 Expression =>
776 Make_Op_Add (Loc,
777 Left_Opnd => New_Occurrence_Of (Pos, Loc),
778 Right_Opnd => Make_Integer_Literal (Loc, 1))));
779 end Build_Task_Image_Prefix;
780
781 -----------------------------
782 -- Build_Task_Record_Image --
783 -----------------------------
784
785 function Build_Task_Record_Image
786 (Loc : Source_Ptr;
787 Id_Ref : Node_Id;
788 Dyn : Boolean := False) return Node_Id
789 is
790 Len : Entity_Id;
791 -- Total length of generated name
792
793 Pos : Entity_Id;
794 -- Index into result
795
796 Res : Entity_Id;
797 -- String to hold result
798
799 Pref : Entity_Id;
800 -- Name of enclosing variable, prefix of resulting name
801
802 Sum : Node_Id;
803 -- Expression to compute total size of string
804
805 Sel : Entity_Id;
806 -- Entity for selector name
807
808 Decls : List_Id := New_List;
809 Stats : List_Id := New_List;
810
811 begin
812 Pref := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
813
814 -- For a dynamic task, the name comes from the target variable.
815 -- For a static one it is a formal of the enclosing init proc.
816
817 if Dyn then
818 Get_Name_String (Chars (Entity (Prefix (Id_Ref))));
819 Append_To (Decls,
820 Make_Object_Declaration (Loc,
821 Defining_Identifier => Pref,
822 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
823 Expression =>
824 Make_String_Literal (Loc,
825 Strval => String_From_Name_Buffer)));
826
827 else
828 Append_To (Decls,
829 Make_Object_Renaming_Declaration (Loc,
830 Defining_Identifier => Pref,
831 Subtype_Mark => New_Occurrence_Of (Standard_String, Loc),
832 Name => Make_Identifier (Loc, Name_uTask_Name)));
833 end if;
834
835 Sel := Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
836
837 Get_Name_String (Chars (Selector_Name (Id_Ref)));
838
839 Append_To (Decls,
840 Make_Object_Declaration (Loc,
841 Defining_Identifier => Sel,
842 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
843 Expression =>
844 Make_String_Literal (Loc,
845 Strval => String_From_Name_Buffer)));
846
847 Sum := Make_Integer_Literal (Loc, Nat (Name_Len + 1));
848
849 Sum :=
850 Make_Op_Add (Loc,
851 Left_Opnd => Sum,
852 Right_Opnd =>
853 Make_Attribute_Reference (Loc,
854 Attribute_Name => Name_Length,
855 Prefix =>
856 New_Occurrence_Of (Pref, Loc),
857 Expressions => New_List (Make_Integer_Literal (Loc, 1))));
858
859 Build_Task_Image_Prefix (Loc, Len, Res, Pos, Pref, Sum, Decls, Stats);
860
861 Set_Character_Literal_Name (Char_Code (Character'Pos ('.')));
862
863 -- Res (Pos) := '.';
864
865 Append_To (Stats,
866 Make_Assignment_Statement (Loc,
867 Name => Make_Indexed_Component (Loc,
868 Prefix => New_Occurrence_Of (Res, Loc),
869 Expressions => New_List (New_Occurrence_Of (Pos, Loc))),
870 Expression =>
871 Make_Character_Literal (Loc,
872 Chars => Name_Find,
873 Char_Literal_Value =>
874 UI_From_Int (Character'Pos ('.')))));
875
876 Append_To (Stats,
877 Make_Assignment_Statement (Loc,
878 Name => New_Occurrence_Of (Pos, Loc),
879 Expression =>
880 Make_Op_Add (Loc,
881 Left_Opnd => New_Occurrence_Of (Pos, Loc),
882 Right_Opnd => Make_Integer_Literal (Loc, 1))));
883
884 -- Res (Pos .. Len) := Selector;
885
886 Append_To (Stats,
887 Make_Assignment_Statement (Loc,
888 Name => Make_Slice (Loc,
889 Prefix => New_Occurrence_Of (Res, Loc),
890 Discrete_Range =>
891 Make_Range (Loc,
892 Low_Bound => New_Occurrence_Of (Pos, Loc),
893 High_Bound => New_Occurrence_Of (Len, Loc))),
894 Expression => New_Occurrence_Of (Sel, Loc)));
895
896 return Build_Task_Image_Function (Loc, Decls, Stats, Res);
897 end Build_Task_Record_Image;
898
899 ----------------------------------
900 -- Component_May_Be_Bit_Aligned --
901 ----------------------------------
902
903 function Component_May_Be_Bit_Aligned (Comp : Entity_Id) return Boolean is
904 begin
905 -- If no component clause, then everything is fine, since the
906 -- back end never bit-misaligns by default, even if there is
907 -- a pragma Packed for the record.
908
909 if No (Component_Clause (Comp)) then
910 return False;
911 end if;
912
913 -- It is only array and record types that cause trouble
914
915 if not Is_Record_Type (Etype (Comp))
916 and then not Is_Array_Type (Etype (Comp))
917 then
918 return False;
919
920 -- If we know that we have a small (64 bits or less) record
921 -- or bit-packed array, then everything is fine, since the
922 -- back end can handle these cases correctly.
923
924 elsif Esize (Comp) <= 64
925 and then (Is_Record_Type (Etype (Comp))
926 or else Is_Bit_Packed_Array (Etype (Comp)))
927 then
928 return False;
929
930 -- Otherwise if the component is not byte aligned, we
931 -- know we have the nasty unaligned case.
932
933 elsif Normalized_First_Bit (Comp) /= Uint_0
934 or else Esize (Comp) mod System_Storage_Unit /= Uint_0
935 then
936 return True;
937
938 -- If we are large and byte aligned, then OK at this level
939
940 else
941 return False;
942 end if;
943 end Component_May_Be_Bit_Aligned;
944
945 -------------------------------
946 -- Convert_To_Actual_Subtype --
947 -------------------------------
948
949 procedure Convert_To_Actual_Subtype (Exp : Entity_Id) is
950 Act_ST : Entity_Id;
951
952 begin
953 Act_ST := Get_Actual_Subtype (Exp);
954
955 if Act_ST = Etype (Exp) then
956 return;
957
958 else
959 Rewrite (Exp,
960 Convert_To (Act_ST, Relocate_Node (Exp)));
961 Analyze_And_Resolve (Exp, Act_ST);
962 end if;
963 end Convert_To_Actual_Subtype;
964
965 -----------------------------------
966 -- Current_Sem_Unit_Declarations --
967 -----------------------------------
968
969 function Current_Sem_Unit_Declarations return List_Id is
970 U : Node_Id := Unit (Cunit (Current_Sem_Unit));
971 Decls : List_Id;
972
973 begin
974 -- If the current unit is a package body, locate the visible
975 -- declarations of the package spec.
976
977 if Nkind (U) = N_Package_Body then
978 U := Unit (Library_Unit (Cunit (Current_Sem_Unit)));
979 end if;
980
981 if Nkind (U) = N_Package_Declaration then
982 U := Specification (U);
983 Decls := Visible_Declarations (U);
984
985 if No (Decls) then
986 Decls := New_List;
987 Set_Visible_Declarations (U, Decls);
988 end if;
989
990 else
991 Decls := Declarations (U);
992
993 if No (Decls) then
994 Decls := New_List;
995 Set_Declarations (U, Decls);
996 end if;
997 end if;
998
999 return Decls;
1000 end Current_Sem_Unit_Declarations;
1001
1002 -----------------------
1003 -- Duplicate_Subexpr --
1004 -----------------------
1005
1006 function Duplicate_Subexpr
1007 (Exp : Node_Id;
1008 Name_Req : Boolean := False) return Node_Id
1009 is
1010 begin
1011 Remove_Side_Effects (Exp, Name_Req);
1012 return New_Copy_Tree (Exp);
1013 end Duplicate_Subexpr;
1014
1015 ---------------------------------
1016 -- Duplicate_Subexpr_No_Checks --
1017 ---------------------------------
1018
1019 function Duplicate_Subexpr_No_Checks
1020 (Exp : Node_Id;
1021 Name_Req : Boolean := False) return Node_Id
1022 is
1023 New_Exp : Node_Id;
1024
1025 begin
1026 Remove_Side_Effects (Exp, Name_Req);
1027 New_Exp := New_Copy_Tree (Exp);
1028 Remove_Checks (New_Exp);
1029 return New_Exp;
1030 end Duplicate_Subexpr_No_Checks;
1031
1032 -----------------------------------
1033 -- Duplicate_Subexpr_Move_Checks --
1034 -----------------------------------
1035
1036 function Duplicate_Subexpr_Move_Checks
1037 (Exp : Node_Id;
1038 Name_Req : Boolean := False) return Node_Id
1039 is
1040 New_Exp : Node_Id;
1041
1042 begin
1043 Remove_Side_Effects (Exp, Name_Req);
1044 New_Exp := New_Copy_Tree (Exp);
1045 Remove_Checks (Exp);
1046 return New_Exp;
1047 end Duplicate_Subexpr_Move_Checks;
1048
1049 --------------------
1050 -- Ensure_Defined --
1051 --------------------
1052
1053 procedure Ensure_Defined (Typ : Entity_Id; N : Node_Id) is
1054 IR : Node_Id;
1055 P : Node_Id;
1056
1057 begin
1058 if Is_Itype (Typ) then
1059 IR := Make_Itype_Reference (Sloc (N));
1060 Set_Itype (IR, Typ);
1061
1062 if not In_Open_Scopes (Scope (Typ))
1063 and then Is_Subprogram (Current_Scope)
1064 and then Scope (Current_Scope) /= Standard_Standard
1065 then
1066 -- Insert node in front of subprogram, to avoid scope anomalies
1067 -- in gigi.
1068
1069 P := Parent (N);
1070 while Present (P)
1071 and then Nkind (P) /= N_Subprogram_Body
1072 loop
1073 P := Parent (P);
1074 end loop;
1075
1076 if Present (P) then
1077 Insert_Action (P, IR);
1078 else
1079 Insert_Action (N, IR);
1080 end if;
1081
1082 else
1083 Insert_Action (N, IR);
1084 end if;
1085 end if;
1086 end Ensure_Defined;
1087
1088 ---------------------
1089 -- Evolve_And_Then --
1090 ---------------------
1091
1092 procedure Evolve_And_Then (Cond : in out Node_Id; Cond1 : Node_Id) is
1093 begin
1094 if No (Cond) then
1095 Cond := Cond1;
1096 else
1097 Cond :=
1098 Make_And_Then (Sloc (Cond1),
1099 Left_Opnd => Cond,
1100 Right_Opnd => Cond1);
1101 end if;
1102 end Evolve_And_Then;
1103
1104 --------------------
1105 -- Evolve_Or_Else --
1106 --------------------
1107
1108 procedure Evolve_Or_Else (Cond : in out Node_Id; Cond1 : Node_Id) is
1109 begin
1110 if No (Cond) then
1111 Cond := Cond1;
1112 else
1113 Cond :=
1114 Make_Or_Else (Sloc (Cond1),
1115 Left_Opnd => Cond,
1116 Right_Opnd => Cond1);
1117 end if;
1118 end Evolve_Or_Else;
1119
1120 ------------------------------
1121 -- Expand_Subtype_From_Expr --
1122 ------------------------------
1123
1124 -- This function is applicable for both static and dynamic allocation of
1125 -- objects which are constrained by an initial expression. Basically it
1126 -- transforms an unconstrained subtype indication into a constrained one.
1127 -- The expression may also be transformed in certain cases in order to
1128 -- avoid multiple evaulation. In the static allocation case, the general
1129 -- scheme is :
1130
1131 -- Val : T := Expr;
1132
1133 -- is transformed into
1134
1135 -- Val : Constrained_Subtype_of_T := Maybe_Modified_Expr;
1136 --
1137 -- Here are the main cases :
1138 --
1139 -- <if Expr is a Slice>
1140 -- Val : T ([Index_Subtype (Expr)]) := Expr;
1141 --
1142 -- <elsif Expr is a String Literal>
1143 -- Val : T (T'First .. T'First + Length (string literal) - 1) := Expr;
1144 --
1145 -- <elsif Expr is Constrained>
1146 -- subtype T is Type_Of_Expr
1147 -- Val : T := Expr;
1148 --
1149 -- <elsif Expr is an entity_name>
1150 -- Val : T (constraints taken from Expr) := Expr;
1151 --
1152 -- <else>
1153 -- type Axxx is access all T;
1154 -- Rval : Axxx := Expr'ref;
1155 -- Val : T (constraints taken from Rval) := Rval.all;
1156
1157 -- ??? note: when the Expression is allocated in the secondary stack
1158 -- we could use it directly instead of copying it by declaring
1159 -- Val : T (...) renames Rval.all
1160
1161 procedure Expand_Subtype_From_Expr
1162 (N : Node_Id;
1163 Unc_Type : Entity_Id;
1164 Subtype_Indic : Node_Id;
1165 Exp : Node_Id)
1166 is
1167 Loc : constant Source_Ptr := Sloc (N);
1168 Exp_Typ : constant Entity_Id := Etype (Exp);
1169 T : Entity_Id;
1170
1171 begin
1172 -- In general we cannot build the subtype if expansion is disabled,
1173 -- because internal entities may not have been defined. However, to
1174 -- avoid some cascaded errors, we try to continue when the expression
1175 -- is an array (or string), because it is safe to compute the bounds.
1176 -- It is in fact required to do so even in a generic context, because
1177 -- there may be constants that depend on bounds of string literal.
1178
1179 if not Expander_Active
1180 and then (No (Etype (Exp))
1181 or else Base_Type (Etype (Exp)) /= Standard_String)
1182 then
1183 return;
1184 end if;
1185
1186 if Nkind (Exp) = N_Slice then
1187 declare
1188 Slice_Type : constant Entity_Id := Etype (First_Index (Exp_Typ));
1189
1190 begin
1191 Rewrite (Subtype_Indic,
1192 Make_Subtype_Indication (Loc,
1193 Subtype_Mark => New_Reference_To (Unc_Type, Loc),
1194 Constraint =>
1195 Make_Index_Or_Discriminant_Constraint (Loc,
1196 Constraints => New_List
1197 (New_Reference_To (Slice_Type, Loc)))));
1198
1199 -- This subtype indication may be used later for contraint checks
1200 -- we better make sure that if a variable was used as a bound of
1201 -- of the original slice, its value is frozen.
1202
1203 Force_Evaluation (Low_Bound (Scalar_Range (Slice_Type)));
1204 Force_Evaluation (High_Bound (Scalar_Range (Slice_Type)));
1205 end;
1206
1207 elsif Ekind (Exp_Typ) = E_String_Literal_Subtype then
1208 Rewrite (Subtype_Indic,
1209 Make_Subtype_Indication (Loc,
1210 Subtype_Mark => New_Reference_To (Unc_Type, Loc),
1211 Constraint =>
1212 Make_Index_Or_Discriminant_Constraint (Loc,
1213 Constraints => New_List (
1214 Make_Literal_Range (Loc,
1215 Literal_Typ => Exp_Typ)))));
1216
1217 elsif Is_Constrained (Exp_Typ)
1218 and then not Is_Class_Wide_Type (Unc_Type)
1219 then
1220 if Is_Itype (Exp_Typ) then
1221
1222 -- No need to generate a new one
1223
1224 T := Exp_Typ;
1225
1226 else
1227 T :=
1228 Make_Defining_Identifier (Loc,
1229 Chars => New_Internal_Name ('T'));
1230
1231 Insert_Action (N,
1232 Make_Subtype_Declaration (Loc,
1233 Defining_Identifier => T,
1234 Subtype_Indication => New_Reference_To (Exp_Typ, Loc)));
1235
1236 -- This type is marked as an itype even though it has an
1237 -- explicit declaration because otherwise it can be marked
1238 -- with Is_Generic_Actual_Type and generate spurious errors.
1239 -- (see sem_ch8.Analyze_Package_Renaming and sem_type.covers)
1240
1241 Set_Is_Itype (T);
1242 Set_Associated_Node_For_Itype (T, Exp);
1243 end if;
1244
1245 Rewrite (Subtype_Indic, New_Reference_To (T, Loc));
1246
1247 -- nothing needs to be done for private types with unknown discriminants
1248 -- if the underlying type is not an unconstrained composite type.
1249
1250 elsif Is_Private_Type (Unc_Type)
1251 and then Has_Unknown_Discriminants (Unc_Type)
1252 and then (not Is_Composite_Type (Underlying_Type (Unc_Type))
1253 or else Is_Constrained (Underlying_Type (Unc_Type)))
1254 then
1255 null;
1256
1257 else
1258 Remove_Side_Effects (Exp);
1259 Rewrite (Subtype_Indic,
1260 Make_Subtype_From_Expr (Exp, Unc_Type));
1261 end if;
1262 end Expand_Subtype_From_Expr;
1263
1264 ------------------
1265 -- Find_Prim_Op --
1266 ------------------
1267
1268 function Find_Prim_Op (T : Entity_Id; Name : Name_Id) return Entity_Id is
1269 Prim : Elmt_Id;
1270 Typ : Entity_Id := T;
1271
1272 begin
1273 if Is_Class_Wide_Type (Typ) then
1274 Typ := Root_Type (Typ);
1275 end if;
1276
1277 Typ := Underlying_Type (Typ);
1278
1279 Prim := First_Elmt (Primitive_Operations (Typ));
1280 while Chars (Node (Prim)) /= Name loop
1281 Next_Elmt (Prim);
1282 pragma Assert (Present (Prim));
1283 end loop;
1284
1285 return Node (Prim);
1286 end Find_Prim_Op;
1287
1288 function Find_Prim_Op
1289 (T : Entity_Id;
1290 Name : TSS_Name_Type) return Entity_Id
1291 is
1292 Prim : Elmt_Id;
1293 Typ : Entity_Id := T;
1294
1295 begin
1296 if Is_Class_Wide_Type (Typ) then
1297 Typ := Root_Type (Typ);
1298 end if;
1299
1300 Typ := Underlying_Type (Typ);
1301
1302 Prim := First_Elmt (Primitive_Operations (Typ));
1303 while not Is_TSS (Node (Prim), Name) loop
1304 Next_Elmt (Prim);
1305 pragma Assert (Present (Prim));
1306 end loop;
1307
1308 return Node (Prim);
1309 end Find_Prim_Op;
1310
1311 ----------------------
1312 -- Force_Evaluation --
1313 ----------------------
1314
1315 procedure Force_Evaluation (Exp : Node_Id; Name_Req : Boolean := False) is
1316 Component_In_Lhs : Boolean := False;
1317 Par : Node_Id;
1318
1319 begin
1320 -- Loop to determine whether there is a component reference in
1321 -- the left hand side if Exp appears on the left side of an
1322 -- assignment statement. Needed to determine if form of result
1323 -- must be a variable.
1324
1325 Par := Exp;
1326 while Present (Par)
1327 and then
1328 (Nkind (Par) = N_Selected_Component
1329 or else
1330 Nkind (Par) = N_Indexed_Component)
1331 loop
1332 if Nkind (Parent (Par)) = N_Assignment_Statement
1333 and then Par = Name (Parent (Par))
1334 then
1335 Component_In_Lhs := True;
1336 exit;
1337 else
1338 Par := Parent (Par);
1339 end if;
1340 end loop;
1341
1342 -- If the expression is a selected component, it is being evaluated
1343 -- as part of a discriminant check. If it is part of a left-hand
1344 -- side, this is the last use of its value and it is safe to create
1345 -- a renaming for it, rather than a temporary. In addition, if it
1346 -- is not an addressable field, creating a temporary may be a problem
1347 -- for gigi, or might drop the value of the assignment. Therefore,
1348 -- if the expression is on the lhs of an assignment, remove side
1349 -- effects without requiring a temporary, and create a renaming.
1350 -- (See remove_side_effects for details).
1351
1352 Remove_Side_Effects
1353 (Exp, Name_Req, Variable_Ref => not Component_In_Lhs);
1354 end Force_Evaluation;
1355
1356 ------------------------
1357 -- Generate_Poll_Call --
1358 ------------------------
1359
1360 procedure Generate_Poll_Call (N : Node_Id) is
1361 begin
1362 -- No poll call if polling not active
1363
1364 if not Polling_Required then
1365 return;
1366
1367 -- Otherwise generate require poll call
1368
1369 else
1370 Insert_Before_And_Analyze (N,
1371 Make_Procedure_Call_Statement (Sloc (N),
1372 Name => New_Occurrence_Of (RTE (RE_Poll), Sloc (N))));
1373 end if;
1374 end Generate_Poll_Call;
1375
1376 ---------------------------------
1377 -- Get_Current_Value_Condition --
1378 ---------------------------------
1379
1380 procedure Get_Current_Value_Condition
1381 (Var : Node_Id;
1382 Op : out Node_Kind;
1383 Val : out Node_Id)
1384 is
1385 Loc : constant Source_Ptr := Sloc (Var);
1386 CV : constant Node_Id := Current_Value (Entity (Var));
1387 Sens : Boolean;
1388 Stm : Node_Id;
1389 Cond : Node_Id;
1390
1391 begin
1392 Op := N_Empty;
1393 Val := Empty;
1394
1395 -- If statement. Condition is known true in THEN section, known False
1396 -- in any ELSIF or ELSE part, and unknown outside the IF statement.
1397
1398 if Nkind (CV) = N_If_Statement then
1399
1400 -- Before start of IF statement
1401
1402 if Loc < Sloc (CV) then
1403 return;
1404
1405 -- After end of IF statement
1406
1407 elsif Loc >= Sloc (CV) + Text_Ptr (UI_To_Int (End_Span (CV))) then
1408 return;
1409 end if;
1410
1411 -- At this stage we know that we are within the IF statement, but
1412 -- unfortunately, the tree does not record the SLOC of the ELSE so
1413 -- we cannot use a simple SLOC comparison to distinguish between
1414 -- the then/else statements, so we have to climb the tree.
1415
1416 declare
1417 N : Node_Id;
1418
1419 begin
1420 N := Parent (Var);
1421 while Parent (N) /= CV loop
1422 N := Parent (N);
1423
1424 -- If we fall off the top of the tree, then that's odd, but
1425 -- perhaps it could occur in some error situation, and the
1426 -- safest response is simply to assume that the outcome of
1427 -- the condition is unknown. No point in bombing during an
1428 -- attempt to optimize things.
1429
1430 if No (N) then
1431 return;
1432 end if;
1433 end loop;
1434
1435 -- Now we have N pointing to a node whose parent is the IF
1436 -- statement in question, so now we can tell if we are within
1437 -- the THEN statements.
1438
1439 if Is_List_Member (N)
1440 and then List_Containing (N) = Then_Statements (CV)
1441 then
1442 Sens := True;
1443
1444 -- Otherwise we must be in ELSIF or ELSE part
1445
1446 else
1447 Sens := False;
1448 end if;
1449 end;
1450
1451 -- ELSIF part. Condition is known true within the referenced
1452 -- ELSIF, known False in any subsequent ELSIF or ELSE part,
1453 -- and unknown before the ELSE part or after the IF statement.
1454
1455 elsif Nkind (CV) = N_Elsif_Part then
1456 Stm := Parent (CV);
1457
1458 -- Before start of ELSIF part
1459
1460 if Loc < Sloc (CV) then
1461 return;
1462
1463 -- After end of IF statement
1464
1465 elsif Loc >= Sloc (Stm) +
1466 Text_Ptr (UI_To_Int (End_Span (Stm)))
1467 then
1468 return;
1469 end if;
1470
1471 -- Again we lack the SLOC of the ELSE, so we need to climb the
1472 -- tree to see if we are within the ELSIF part in question.
1473
1474 declare
1475 N : Node_Id;
1476
1477 begin
1478 N := Parent (Var);
1479 while Parent (N) /= Stm loop
1480 N := Parent (N);
1481
1482 -- If we fall off the top of the tree, then that's odd, but
1483 -- perhaps it could occur in some error situation, and the
1484 -- safest response is simply to assume that the outcome of
1485 -- the condition is unknown. No point in bombing during an
1486 -- attempt to optimize things.
1487
1488 if No (N) then
1489 return;
1490 end if;
1491 end loop;
1492
1493 -- Now we have N pointing to a node whose parent is the IF
1494 -- statement in question, so see if is the ELSIF part we want.
1495 -- the THEN statements.
1496
1497 if N = CV then
1498 Sens := True;
1499
1500 -- Otherwise we must be in susbequent ELSIF or ELSE part
1501
1502 else
1503 Sens := False;
1504 end if;
1505 end;
1506
1507 -- All other cases of Current_Value settings
1508
1509 else
1510 return;
1511 end if;
1512
1513 -- If we fall through here, then we have a reportable
1514 -- condition, Sens is True if the condition is true and
1515 -- False if it needs inverting.
1516
1517 -- Deal with NOT operators, inverting sense
1518
1519 Cond := Condition (CV);
1520 while Nkind (Cond) = N_Op_Not loop
1521 Cond := Right_Opnd (Cond);
1522 Sens := not Sens;
1523 end loop;
1524
1525 -- Now we must have a relational operator
1526
1527 pragma Assert (Entity (Var) = Entity (Left_Opnd (Cond)));
1528 Val := Right_Opnd (Cond);
1529 Op := Nkind (Cond);
1530
1531 if Sens = False then
1532 case Op is
1533 when N_Op_Eq => Op := N_Op_Ne;
1534 when N_Op_Ne => Op := N_Op_Eq;
1535 when N_Op_Lt => Op := N_Op_Ge;
1536 when N_Op_Gt => Op := N_Op_Le;
1537 when N_Op_Le => Op := N_Op_Gt;
1538 when N_Op_Ge => Op := N_Op_Lt;
1539
1540 -- No other entry should be possible
1541
1542 when others =>
1543 raise Program_Error;
1544 end case;
1545 end if;
1546 end Get_Current_Value_Condition;
1547
1548 --------------------
1549 -- Homonym_Number --
1550 --------------------
1551
1552 function Homonym_Number (Subp : Entity_Id) return Nat is
1553 Count : Nat;
1554 Hom : Entity_Id;
1555
1556 begin
1557 Count := 1;
1558 Hom := Homonym (Subp);
1559 while Present (Hom) loop
1560 if Scope (Hom) = Scope (Subp) then
1561 Count := Count + 1;
1562 end if;
1563
1564 Hom := Homonym (Hom);
1565 end loop;
1566
1567 return Count;
1568 end Homonym_Number;
1569
1570 ------------------------------
1571 -- In_Unconditional_Context --
1572 ------------------------------
1573
1574 function In_Unconditional_Context (Node : Node_Id) return Boolean is
1575 P : Node_Id;
1576
1577 begin
1578 P := Node;
1579 while Present (P) loop
1580 case Nkind (P) is
1581 when N_Subprogram_Body =>
1582 return True;
1583
1584 when N_If_Statement =>
1585 return False;
1586
1587 when N_Loop_Statement =>
1588 return False;
1589
1590 when N_Case_Statement =>
1591 return False;
1592
1593 when others =>
1594 P := Parent (P);
1595 end case;
1596 end loop;
1597
1598 return False;
1599 end In_Unconditional_Context;
1600
1601 -------------------
1602 -- Insert_Action --
1603 -------------------
1604
1605 procedure Insert_Action (Assoc_Node : Node_Id; Ins_Action : Node_Id) is
1606 begin
1607 if Present (Ins_Action) then
1608 Insert_Actions (Assoc_Node, New_List (Ins_Action));
1609 end if;
1610 end Insert_Action;
1611
1612 -- Version with check(s) suppressed
1613
1614 procedure Insert_Action
1615 (Assoc_Node : Node_Id; Ins_Action : Node_Id; Suppress : Check_Id)
1616 is
1617 begin
1618 Insert_Actions (Assoc_Node, New_List (Ins_Action), Suppress);
1619 end Insert_Action;
1620
1621 --------------------
1622 -- Insert_Actions --
1623 --------------------
1624
1625 procedure Insert_Actions (Assoc_Node : Node_Id; Ins_Actions : List_Id) is
1626 N : Node_Id;
1627 P : Node_Id;
1628
1629 Wrapped_Node : Node_Id := Empty;
1630
1631 begin
1632 if No (Ins_Actions) or else Is_Empty_List (Ins_Actions) then
1633 return;
1634 end if;
1635
1636 -- Ignore insert of actions from inside default expression in the
1637 -- special preliminary analyze mode. Any insertions at this point
1638 -- have no relevance, since we are only doing the analyze to freeze
1639 -- the types of any static expressions. See section "Handling of
1640 -- Default Expressions" in the spec of package Sem for further details.
1641
1642 if In_Default_Expression then
1643 return;
1644 end if;
1645
1646 -- If the action derives from stuff inside a record, then the actions
1647 -- are attached to the current scope, to be inserted and analyzed on
1648 -- exit from the scope. The reason for this is that we may also
1649 -- be generating freeze actions at the same time, and they must
1650 -- eventually be elaborated in the correct order.
1651
1652 if Is_Record_Type (Current_Scope)
1653 and then not Is_Frozen (Current_Scope)
1654 then
1655 if No (Scope_Stack.Table
1656 (Scope_Stack.Last).Pending_Freeze_Actions)
1657 then
1658 Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions :=
1659 Ins_Actions;
1660 else
1661 Append_List
1662 (Ins_Actions,
1663 Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions);
1664 end if;
1665
1666 return;
1667 end if;
1668
1669 -- We now intend to climb up the tree to find the right point to
1670 -- insert the actions. We start at Assoc_Node, unless this node is
1671 -- a subexpression in which case we start with its parent. We do this
1672 -- for two reasons. First it speeds things up. Second, if Assoc_Node
1673 -- is itself one of the special nodes like N_And_Then, then we assume
1674 -- that an initial request to insert actions for such a node does not
1675 -- expect the actions to get deposited in the node for later handling
1676 -- when the node is expanded, since clearly the node is being dealt
1677 -- with by the caller. Note that in the subexpression case, N is
1678 -- always the child we came from.
1679
1680 -- N_Raise_xxx_Error is an annoying special case, it is a statement
1681 -- if it has type Standard_Void_Type, and a subexpression otherwise.
1682 -- otherwise. Procedure attribute references are also statements.
1683
1684 if Nkind (Assoc_Node) in N_Subexpr
1685 and then (Nkind (Assoc_Node) in N_Raise_xxx_Error
1686 or else Etype (Assoc_Node) /= Standard_Void_Type)
1687 and then (Nkind (Assoc_Node) /= N_Attribute_Reference
1688 or else
1689 not Is_Procedure_Attribute_Name
1690 (Attribute_Name (Assoc_Node)))
1691 then
1692 P := Assoc_Node; -- ??? does not agree with above!
1693 N := Parent (Assoc_Node);
1694
1695 -- Non-subexpression case. Note that N is initially Empty in this
1696 -- case (N is only guaranteed Non-Empty in the subexpr case).
1697
1698 else
1699 P := Assoc_Node;
1700 N := Empty;
1701 end if;
1702
1703 -- Capture root of the transient scope
1704
1705 if Scope_Is_Transient then
1706 Wrapped_Node := Node_To_Be_Wrapped;
1707 end if;
1708
1709 loop
1710 pragma Assert (Present (P));
1711
1712 case Nkind (P) is
1713
1714 -- Case of right operand of AND THEN or OR ELSE. Put the actions
1715 -- in the Actions field of the right operand. They will be moved
1716 -- out further when the AND THEN or OR ELSE operator is expanded.
1717 -- Nothing special needs to be done for the left operand since
1718 -- in that case the actions are executed unconditionally.
1719
1720 when N_And_Then | N_Or_Else =>
1721 if N = Right_Opnd (P) then
1722 if Present (Actions (P)) then
1723 Insert_List_After_And_Analyze
1724 (Last (Actions (P)), Ins_Actions);
1725 else
1726 Set_Actions (P, Ins_Actions);
1727 Analyze_List (Actions (P));
1728 end if;
1729
1730 return;
1731 end if;
1732
1733 -- Then or Else operand of conditional expression. Add actions to
1734 -- Then_Actions or Else_Actions field as appropriate. The actions
1735 -- will be moved further out when the conditional is expanded.
1736
1737 when N_Conditional_Expression =>
1738 declare
1739 ThenX : constant Node_Id := Next (First (Expressions (P)));
1740 ElseX : constant Node_Id := Next (ThenX);
1741
1742 begin
1743 -- Actions belong to the then expression, temporarily
1744 -- place them as Then_Actions of the conditional expr.
1745 -- They will be moved to the proper place later when
1746 -- the conditional expression is expanded.
1747
1748 if N = ThenX then
1749 if Present (Then_Actions (P)) then
1750 Insert_List_After_And_Analyze
1751 (Last (Then_Actions (P)), Ins_Actions);
1752 else
1753 Set_Then_Actions (P, Ins_Actions);
1754 Analyze_List (Then_Actions (P));
1755 end if;
1756
1757 return;
1758
1759 -- Actions belong to the else expression, temporarily
1760 -- place them as Else_Actions of the conditional expr.
1761 -- They will be moved to the proper place later when
1762 -- the conditional expression is expanded.
1763
1764 elsif N = ElseX then
1765 if Present (Else_Actions (P)) then
1766 Insert_List_After_And_Analyze
1767 (Last (Else_Actions (P)), Ins_Actions);
1768 else
1769 Set_Else_Actions (P, Ins_Actions);
1770 Analyze_List (Else_Actions (P));
1771 end if;
1772
1773 return;
1774
1775 -- Actions belong to the condition. In this case they are
1776 -- unconditionally executed, and so we can continue the
1777 -- search for the proper insert point.
1778
1779 else
1780 null;
1781 end if;
1782 end;
1783
1784 -- Case of appearing in the condition of a while expression or
1785 -- elsif. We insert the actions into the Condition_Actions field.
1786 -- They will be moved further out when the while loop or elsif
1787 -- is analyzed.
1788
1789 when N_Iteration_Scheme |
1790 N_Elsif_Part
1791 =>
1792 if N = Condition (P) then
1793 if Present (Condition_Actions (P)) then
1794 Insert_List_After_And_Analyze
1795 (Last (Condition_Actions (P)), Ins_Actions);
1796 else
1797 Set_Condition_Actions (P, Ins_Actions);
1798
1799 -- Set the parent of the insert actions explicitly.
1800 -- This is not a syntactic field, but we need the
1801 -- parent field set, in particular so that freeze
1802 -- can understand that it is dealing with condition
1803 -- actions, and properly insert the freezing actions.
1804
1805 Set_Parent (Ins_Actions, P);
1806 Analyze_List (Condition_Actions (P));
1807 end if;
1808
1809 return;
1810 end if;
1811
1812 -- Statements, declarations, pragmas, representation clauses
1813
1814 when
1815 -- Statements
1816
1817 N_Procedure_Call_Statement |
1818 N_Statement_Other_Than_Procedure_Call |
1819
1820 -- Pragmas
1821
1822 N_Pragma |
1823
1824 -- Representation_Clause
1825
1826 N_At_Clause |
1827 N_Attribute_Definition_Clause |
1828 N_Enumeration_Representation_Clause |
1829 N_Record_Representation_Clause |
1830
1831 -- Declarations
1832
1833 N_Abstract_Subprogram_Declaration |
1834 N_Entry_Body |
1835 N_Exception_Declaration |
1836 N_Exception_Renaming_Declaration |
1837 N_Formal_Abstract_Subprogram_Declaration |
1838 N_Formal_Concrete_Subprogram_Declaration |
1839 N_Formal_Object_Declaration |
1840 N_Formal_Type_Declaration |
1841 N_Full_Type_Declaration |
1842 N_Function_Instantiation |
1843 N_Generic_Function_Renaming_Declaration |
1844 N_Generic_Package_Declaration |
1845 N_Generic_Package_Renaming_Declaration |
1846 N_Generic_Procedure_Renaming_Declaration |
1847 N_Generic_Subprogram_Declaration |
1848 N_Implicit_Label_Declaration |
1849 N_Incomplete_Type_Declaration |
1850 N_Number_Declaration |
1851 N_Object_Declaration |
1852 N_Object_Renaming_Declaration |
1853 N_Package_Body |
1854 N_Package_Body_Stub |
1855 N_Package_Declaration |
1856 N_Package_Instantiation |
1857 N_Package_Renaming_Declaration |
1858 N_Private_Extension_Declaration |
1859 N_Private_Type_Declaration |
1860 N_Procedure_Instantiation |
1861 N_Protected_Body_Stub |
1862 N_Protected_Type_Declaration |
1863 N_Single_Task_Declaration |
1864 N_Subprogram_Body |
1865 N_Subprogram_Body_Stub |
1866 N_Subprogram_Declaration |
1867 N_Subprogram_Renaming_Declaration |
1868 N_Subtype_Declaration |
1869 N_Task_Body |
1870 N_Task_Body_Stub |
1871 N_Task_Type_Declaration |
1872
1873 -- Freeze entity behaves like a declaration or statement
1874
1875 N_Freeze_Entity
1876 =>
1877 -- Do not insert here if the item is not a list member (this
1878 -- happens for example with a triggering statement, and the
1879 -- proper approach is to insert before the entire select).
1880
1881 if not Is_List_Member (P) then
1882 null;
1883
1884 -- Do not insert if parent of P is an N_Component_Association
1885 -- node (i.e. we are in the context of an N_Aggregate node.
1886 -- In this case we want to insert before the entire aggregate.
1887
1888 elsif Nkind (Parent (P)) = N_Component_Association then
1889 null;
1890
1891 -- Do not insert if the parent of P is either an N_Variant
1892 -- node or an N_Record_Definition node, meaning in either
1893 -- case that P is a member of a component list, and that
1894 -- therefore the actions should be inserted outside the
1895 -- complete record declaration.
1896
1897 elsif Nkind (Parent (P)) = N_Variant
1898 or else Nkind (Parent (P)) = N_Record_Definition
1899 then
1900 null;
1901
1902 -- Do not insert freeze nodes within the loop generated for
1903 -- an aggregate, because they may be elaborated too late for
1904 -- subsequent use in the back end: within a package spec the
1905 -- loop is part of the elaboration procedure and is only
1906 -- elaborated during the second pass.
1907 -- If the loop comes from source, or the entity is local to
1908 -- the loop itself it must remain within.
1909
1910 elsif Nkind (Parent (P)) = N_Loop_Statement
1911 and then not Comes_From_Source (Parent (P))
1912 and then Nkind (First (Ins_Actions)) = N_Freeze_Entity
1913 and then
1914 Scope (Entity (First (Ins_Actions))) /= Current_Scope
1915 then
1916 null;
1917
1918 -- Otherwise we can go ahead and do the insertion
1919
1920 elsif P = Wrapped_Node then
1921 Store_Before_Actions_In_Scope (Ins_Actions);
1922 return;
1923
1924 else
1925 Insert_List_Before_And_Analyze (P, Ins_Actions);
1926 return;
1927 end if;
1928
1929 -- A special case, N_Raise_xxx_Error can act either as a
1930 -- statement or a subexpression. We tell the difference
1931 -- by looking at the Etype. It is set to Standard_Void_Type
1932 -- in the statement case.
1933
1934 when
1935 N_Raise_xxx_Error =>
1936 if Etype (P) = Standard_Void_Type then
1937 if P = Wrapped_Node then
1938 Store_Before_Actions_In_Scope (Ins_Actions);
1939 else
1940 Insert_List_Before_And_Analyze (P, Ins_Actions);
1941 end if;
1942
1943 return;
1944
1945 -- In the subexpression case, keep climbing
1946
1947 else
1948 null;
1949 end if;
1950
1951 -- If a component association appears within a loop created for
1952 -- an array aggregate, attach the actions to the association so
1953 -- they can be subsequently inserted within the loop. For other
1954 -- component associations insert outside of the aggregate. For
1955 -- an association that will generate a loop, its Loop_Actions
1956 -- attribute is already initialized (see exp_aggr.adb).
1957
1958 -- The list of loop_actions can in turn generate additional ones,
1959 -- that are inserted before the associated node. If the associated
1960 -- node is outside the aggregate, the new actions are collected
1961 -- at the end of the loop actions, to respect the order in which
1962 -- they are to be elaborated.
1963
1964 when
1965 N_Component_Association =>
1966 if Nkind (Parent (P)) = N_Aggregate
1967 and then Present (Loop_Actions (P))
1968 then
1969 if Is_Empty_List (Loop_Actions (P)) then
1970 Set_Loop_Actions (P, Ins_Actions);
1971 Analyze_List (Ins_Actions);
1972
1973 else
1974 declare
1975 Decl : Node_Id;
1976
1977 begin
1978 -- Check whether these actions were generated
1979 -- by a declaration that is part of the loop_
1980 -- actions for the component_association.
1981
1982 Decl := Assoc_Node;
1983 while Present (Decl) loop
1984 exit when Parent (Decl) = P
1985 and then Is_List_Member (Decl)
1986 and then
1987 List_Containing (Decl) = Loop_Actions (P);
1988 Decl := Parent (Decl);
1989 end loop;
1990
1991 if Present (Decl) then
1992 Insert_List_Before_And_Analyze
1993 (Decl, Ins_Actions);
1994 else
1995 Insert_List_After_And_Analyze
1996 (Last (Loop_Actions (P)), Ins_Actions);
1997 end if;
1998 end;
1999 end if;
2000
2001 return;
2002
2003 else
2004 null;
2005 end if;
2006
2007 -- Another special case, an attribute denoting a procedure call
2008
2009 when
2010 N_Attribute_Reference =>
2011 if Is_Procedure_Attribute_Name (Attribute_Name (P)) then
2012 if P = Wrapped_Node then
2013 Store_Before_Actions_In_Scope (Ins_Actions);
2014 else
2015 Insert_List_Before_And_Analyze (P, Ins_Actions);
2016 end if;
2017
2018 return;
2019
2020 -- In the subexpression case, keep climbing
2021
2022 else
2023 null;
2024 end if;
2025
2026 -- For all other node types, keep climbing tree
2027
2028 when
2029 N_Abortable_Part |
2030 N_Accept_Alternative |
2031 N_Access_Definition |
2032 N_Access_Function_Definition |
2033 N_Access_Procedure_Definition |
2034 N_Access_To_Object_Definition |
2035 N_Aggregate |
2036 N_Allocator |
2037 N_Case_Statement_Alternative |
2038 N_Character_Literal |
2039 N_Compilation_Unit |
2040 N_Compilation_Unit_Aux |
2041 N_Component_Clause |
2042 N_Component_Declaration |
2043 N_Component_Definition |
2044 N_Component_List |
2045 N_Constrained_Array_Definition |
2046 N_Decimal_Fixed_Point_Definition |
2047 N_Defining_Character_Literal |
2048 N_Defining_Identifier |
2049 N_Defining_Operator_Symbol |
2050 N_Defining_Program_Unit_Name |
2051 N_Delay_Alternative |
2052 N_Delta_Constraint |
2053 N_Derived_Type_Definition |
2054 N_Designator |
2055 N_Digits_Constraint |
2056 N_Discriminant_Association |
2057 N_Discriminant_Specification |
2058 N_Empty |
2059 N_Entry_Body_Formal_Part |
2060 N_Entry_Call_Alternative |
2061 N_Entry_Declaration |
2062 N_Entry_Index_Specification |
2063 N_Enumeration_Type_Definition |
2064 N_Error |
2065 N_Exception_Handler |
2066 N_Expanded_Name |
2067 N_Explicit_Dereference |
2068 N_Extension_Aggregate |
2069 N_Floating_Point_Definition |
2070 N_Formal_Decimal_Fixed_Point_Definition |
2071 N_Formal_Derived_Type_Definition |
2072 N_Formal_Discrete_Type_Definition |
2073 N_Formal_Floating_Point_Definition |
2074 N_Formal_Modular_Type_Definition |
2075 N_Formal_Ordinary_Fixed_Point_Definition |
2076 N_Formal_Package_Declaration |
2077 N_Formal_Private_Type_Definition |
2078 N_Formal_Signed_Integer_Type_Definition |
2079 N_Function_Call |
2080 N_Function_Specification |
2081 N_Generic_Association |
2082 N_Handled_Sequence_Of_Statements |
2083 N_Identifier |
2084 N_In |
2085 N_Index_Or_Discriminant_Constraint |
2086 N_Indexed_Component |
2087 N_Integer_Literal |
2088 N_Itype_Reference |
2089 N_Label |
2090 N_Loop_Parameter_Specification |
2091 N_Mod_Clause |
2092 N_Modular_Type_Definition |
2093 N_Not_In |
2094 N_Null |
2095 N_Op_Abs |
2096 N_Op_Add |
2097 N_Op_And |
2098 N_Op_Concat |
2099 N_Op_Divide |
2100 N_Op_Eq |
2101 N_Op_Expon |
2102 N_Op_Ge |
2103 N_Op_Gt |
2104 N_Op_Le |
2105 N_Op_Lt |
2106 N_Op_Minus |
2107 N_Op_Mod |
2108 N_Op_Multiply |
2109 N_Op_Ne |
2110 N_Op_Not |
2111 N_Op_Or |
2112 N_Op_Plus |
2113 N_Op_Rem |
2114 N_Op_Rotate_Left |
2115 N_Op_Rotate_Right |
2116 N_Op_Shift_Left |
2117 N_Op_Shift_Right |
2118 N_Op_Shift_Right_Arithmetic |
2119 N_Op_Subtract |
2120 N_Op_Xor |
2121 N_Operator_Symbol |
2122 N_Ordinary_Fixed_Point_Definition |
2123 N_Others_Choice |
2124 N_Package_Specification |
2125 N_Parameter_Association |
2126 N_Parameter_Specification |
2127 N_Pragma_Argument_Association |
2128 N_Procedure_Specification |
2129 N_Protected_Body |
2130 N_Protected_Definition |
2131 N_Qualified_Expression |
2132 N_Range |
2133 N_Range_Constraint |
2134 N_Real_Literal |
2135 N_Real_Range_Specification |
2136 N_Record_Definition |
2137 N_Reference |
2138 N_Selected_Component |
2139 N_Signed_Integer_Type_Definition |
2140 N_Single_Protected_Declaration |
2141 N_Slice |
2142 N_String_Literal |
2143 N_Subprogram_Info |
2144 N_Subtype_Indication |
2145 N_Subunit |
2146 N_Task_Definition |
2147 N_Terminate_Alternative |
2148 N_Triggering_Alternative |
2149 N_Type_Conversion |
2150 N_Unchecked_Expression |
2151 N_Unchecked_Type_Conversion |
2152 N_Unconstrained_Array_Definition |
2153 N_Unused_At_End |
2154 N_Unused_At_Start |
2155 N_Use_Package_Clause |
2156 N_Use_Type_Clause |
2157 N_Variant |
2158 N_Variant_Part |
2159 N_Validate_Unchecked_Conversion |
2160 N_With_Clause |
2161 N_With_Type_Clause
2162 =>
2163 null;
2164
2165 end case;
2166
2167 -- Make sure that inserted actions stay in the transient scope
2168
2169 if P = Wrapped_Node then
2170 Store_Before_Actions_In_Scope (Ins_Actions);
2171 return;
2172 end if;
2173
2174 -- If we fall through above tests, keep climbing tree
2175
2176 N := P;
2177
2178 if Nkind (Parent (N)) = N_Subunit then
2179
2180 -- This is the proper body corresponding to a stub. Insertion
2181 -- must be done at the point of the stub, which is in the decla-
2182 -- tive part of the parent unit.
2183
2184 P := Corresponding_Stub (Parent (N));
2185
2186 else
2187 P := Parent (N);
2188 end if;
2189 end loop;
2190
2191 end Insert_Actions;
2192
2193 -- Version with check(s) suppressed
2194
2195 procedure Insert_Actions
2196 (Assoc_Node : Node_Id; Ins_Actions : List_Id; Suppress : Check_Id)
2197 is
2198 begin
2199 if Suppress = All_Checks then
2200 declare
2201 Svg : constant Suppress_Array := Scope_Suppress;
2202
2203 begin
2204 Scope_Suppress := (others => True);
2205 Insert_Actions (Assoc_Node, Ins_Actions);
2206 Scope_Suppress := Svg;
2207 end;
2208
2209 else
2210 declare
2211 Svg : constant Boolean := Scope_Suppress (Suppress);
2212
2213 begin
2214 Scope_Suppress (Suppress) := True;
2215 Insert_Actions (Assoc_Node, Ins_Actions);
2216 Scope_Suppress (Suppress) := Svg;
2217 end;
2218 end if;
2219 end Insert_Actions;
2220
2221 --------------------------
2222 -- Insert_Actions_After --
2223 --------------------------
2224
2225 procedure Insert_Actions_After
2226 (Assoc_Node : Node_Id;
2227 Ins_Actions : List_Id)
2228 is
2229 begin
2230 if Scope_Is_Transient
2231 and then Assoc_Node = Node_To_Be_Wrapped
2232 then
2233 Store_After_Actions_In_Scope (Ins_Actions);
2234 else
2235 Insert_List_After_And_Analyze (Assoc_Node, Ins_Actions);
2236 end if;
2237 end Insert_Actions_After;
2238
2239 ---------------------------------
2240 -- Insert_Library_Level_Action --
2241 ---------------------------------
2242
2243 procedure Insert_Library_Level_Action (N : Node_Id) is
2244 Aux : constant Node_Id := Aux_Decls_Node (Cunit (Main_Unit));
2245
2246 begin
2247 New_Scope (Cunit_Entity (Main_Unit));
2248
2249 if No (Actions (Aux)) then
2250 Set_Actions (Aux, New_List (N));
2251 else
2252 Append (N, Actions (Aux));
2253 end if;
2254
2255 Analyze (N);
2256 Pop_Scope;
2257 end Insert_Library_Level_Action;
2258
2259 ----------------------------------
2260 -- Insert_Library_Level_Actions --
2261 ----------------------------------
2262
2263 procedure Insert_Library_Level_Actions (L : List_Id) is
2264 Aux : constant Node_Id := Aux_Decls_Node (Cunit (Main_Unit));
2265
2266 begin
2267 if Is_Non_Empty_List (L) then
2268 New_Scope (Cunit_Entity (Main_Unit));
2269
2270 if No (Actions (Aux)) then
2271 Set_Actions (Aux, L);
2272 Analyze_List (L);
2273 else
2274 Insert_List_After_And_Analyze (Last (Actions (Aux)), L);
2275 end if;
2276
2277 Pop_Scope;
2278 end if;
2279 end Insert_Library_Level_Actions;
2280
2281 ----------------------
2282 -- Inside_Init_Proc --
2283 ----------------------
2284
2285 function Inside_Init_Proc return Boolean is
2286 S : Entity_Id;
2287
2288 begin
2289 S := Current_Scope;
2290 while Present (S)
2291 and then S /= Standard_Standard
2292 loop
2293 if Is_Init_Proc (S) then
2294 return True;
2295 else
2296 S := Scope (S);
2297 end if;
2298 end loop;
2299
2300 return False;
2301 end Inside_Init_Proc;
2302
2303 ----------------------------
2304 -- Is_All_Null_Statements --
2305 ----------------------------
2306
2307 function Is_All_Null_Statements (L : List_Id) return Boolean is
2308 Stm : Node_Id;
2309
2310 begin
2311 Stm := First (L);
2312 while Present (Stm) loop
2313 if Nkind (Stm) /= N_Null_Statement then
2314 return False;
2315 end if;
2316
2317 Next (Stm);
2318 end loop;
2319
2320 return True;
2321 end Is_All_Null_Statements;
2322
2323 ----------------------------------
2324 -- Is_Possibly_Unaligned_Object --
2325 ----------------------------------
2326
2327 function Is_Possibly_Unaligned_Object (N : Node_Id) return Boolean is
2328 T : constant Entity_Id := Etype (N);
2329
2330 begin
2331 -- If renamed object, apply test to underlying object
2332
2333 if Is_Entity_Name (N)
2334 and then Is_Object (Entity (N))
2335 and then Present (Renamed_Object (Entity (N)))
2336 then
2337 return Is_Possibly_Unaligned_Object (Renamed_Object (Entity (N)));
2338 end if;
2339
2340 -- Tagged and controlled types and aliased types are always aligned,
2341 -- as are concurrent types.
2342
2343 if Is_Aliased (T)
2344 or else Has_Controlled_Component (T)
2345 or else Is_Concurrent_Type (T)
2346 or else Is_Tagged_Type (T)
2347 or else Is_Controlled (T)
2348 then
2349 return False;
2350 end if;
2351
2352 -- If this is an element of a packed array, may be unaligned
2353
2354 if Is_Ref_To_Bit_Packed_Array (N) then
2355 return True;
2356 end if;
2357
2358 -- Case of component reference
2359
2360 if Nkind (N) = N_Selected_Component then
2361 declare
2362 P : constant Node_Id := Prefix (N);
2363 C : constant Entity_Id := Entity (Selector_Name (N));
2364 M : Nat;
2365 S : Nat;
2366
2367 begin
2368 -- If component reference is for an array with non-static bounds,
2369 -- then it is always aligned, we can only unaligned arrays with
2370 -- static bounds (more accurately bounds known at compile time)
2371
2372 if Is_Array_Type (T)
2373 and then not Compile_Time_Known_Bounds (T)
2374 then
2375 return False;
2376 end if;
2377
2378 -- If component is aliased, it is definitely properly aligned
2379
2380 if Is_Aliased (C) then
2381 return False;
2382 end if;
2383
2384 -- If component is for a type implemented as a scalar, and the
2385 -- record is packed, and the component is other than the first
2386 -- component of the record, then the component may be unaligned.
2387
2388 if Is_Packed (Etype (P))
2389 and then Represented_As_Scalar (Etype (C))
2390 and then First_Entity (Scope (C)) /= C
2391 then
2392 return True;
2393 end if;
2394
2395 -- Compute maximum possible alignment for T
2396
2397 -- If alignment is known, then that settles things
2398
2399 if Known_Alignment (T) then
2400 M := UI_To_Int (Alignment (T));
2401
2402 -- If alignment is not known, tentatively set max alignment
2403
2404 else
2405 M := Ttypes.Maximum_Alignment;
2406
2407 -- We can reduce this if the Esize is known since the default
2408 -- alignment will never be more than the smallest power of 2
2409 -- that does not exceed this Esize value.
2410
2411 if Known_Esize (T) then
2412 S := UI_To_Int (Esize (T));
2413
2414 while (M / 2) >= S loop
2415 M := M / 2;
2416 end loop;
2417 end if;
2418 end if;
2419
2420 -- If the component reference is for a record that has a specified
2421 -- alignment, and we either know it is too small, or cannot tell,
2422 -- then the component may be unaligned
2423
2424 if Known_Alignment (Etype (P))
2425 and then Alignment (Etype (P)) < Ttypes.Maximum_Alignment
2426 and then M > Alignment (Etype (P))
2427 then
2428 return True;
2429 end if;
2430
2431 -- Case of component clause present which may specify an
2432 -- unaligned position.
2433
2434 if Present (Component_Clause (C)) then
2435
2436 -- Otherwise we can do a test to make sure that the actual
2437 -- start position in the record, and the length, are both
2438 -- consistent with the required alignment. If not, we know
2439 -- that we are unaligned.
2440
2441 declare
2442 Align_In_Bits : constant Nat := M * System_Storage_Unit;
2443 begin
2444 if Component_Bit_Offset (C) mod Align_In_Bits /= 0
2445 or else Esize (C) mod Align_In_Bits /= 0
2446 then
2447 return True;
2448 end if;
2449 end;
2450 end if;
2451
2452 -- Otherwise, for a component reference, test prefix
2453
2454 return Is_Possibly_Unaligned_Object (P);
2455 end;
2456
2457 -- If not a component reference, must be aligned
2458
2459 else
2460 return False;
2461 end if;
2462 end Is_Possibly_Unaligned_Object;
2463
2464 ---------------------------------
2465 -- Is_Possibly_Unaligned_Slice --
2466 ---------------------------------
2467
2468 function Is_Possibly_Unaligned_Slice (N : Node_Id) return Boolean is
2469 begin
2470 -- ??? GCC3 will eventually handle strings with arbitrary alignments,
2471 -- but for now the following check must be disabled.
2472
2473 -- if get_gcc_version >= 3 then
2474 -- return False;
2475 -- end if;
2476
2477 -- For renaming case, go to renamed object
2478
2479 if Is_Entity_Name (N)
2480 and then Is_Object (Entity (N))
2481 and then Present (Renamed_Object (Entity (N)))
2482 then
2483 return Is_Possibly_Unaligned_Slice (Renamed_Object (Entity (N)));
2484 end if;
2485
2486 -- The reference must be a slice
2487
2488 if Nkind (N) /= N_Slice then
2489 return False;
2490 end if;
2491
2492 -- Always assume the worst for a nested record component with a
2493 -- component clause, which gigi/gcc does not appear to handle well.
2494 -- It is not clear why this special test is needed at all ???
2495
2496 if Nkind (Prefix (N)) = N_Selected_Component
2497 and then Nkind (Prefix (Prefix (N))) = N_Selected_Component
2498 and then
2499 Present (Component_Clause (Entity (Selector_Name (Prefix (N)))))
2500 then
2501 return True;
2502 end if;
2503
2504 -- We only need to worry if the target has strict alignment
2505
2506 if not Target_Strict_Alignment then
2507 return False;
2508 end if;
2509
2510 -- If it is a slice, then look at the array type being sliced
2511
2512 declare
2513 Sarr : constant Node_Id := Prefix (N);
2514 -- Prefix of the slice, i.e. the array being sliced
2515
2516 Styp : constant Entity_Id := Etype (Prefix (N));
2517 -- Type of the array being sliced
2518
2519 Pref : Node_Id;
2520 Ptyp : Entity_Id;
2521
2522 begin
2523 -- The problems arise if the array object that is being sliced
2524 -- is a component of a record or array, and we cannot guarantee
2525 -- the alignment of the array within its containing object.
2526
2527 -- To investigate this, we look at successive prefixes to see
2528 -- if we have a worrisome indexed or selected component.
2529
2530 Pref := Sarr;
2531 loop
2532 -- Case of array is part of an indexed component reference
2533
2534 if Nkind (Pref) = N_Indexed_Component then
2535 Ptyp := Etype (Prefix (Pref));
2536
2537 -- The only problematic case is when the array is packed,
2538 -- in which case we really know nothing about the alignment
2539 -- of individual components.
2540
2541 if Is_Bit_Packed_Array (Ptyp) then
2542 return True;
2543 end if;
2544
2545 -- Case of array is part of a selected component reference
2546
2547 elsif Nkind (Pref) = N_Selected_Component then
2548 Ptyp := Etype (Prefix (Pref));
2549
2550 -- We are definitely in trouble if the record in question
2551 -- has an alignment, and either we know this alignment is
2552 -- inconsistent with the alignment of the slice, or we
2553 -- don't know what the alignment of the slice should be.
2554
2555 if Known_Alignment (Ptyp)
2556 and then (Unknown_Alignment (Styp)
2557 or else Alignment (Styp) > Alignment (Ptyp))
2558 then
2559 return True;
2560 end if;
2561
2562 -- We are in potential trouble if the record type is packed.
2563 -- We could special case when we know that the array is the
2564 -- first component, but that's not such a simple case ???
2565
2566 if Is_Packed (Ptyp) then
2567 return True;
2568 end if;
2569
2570 -- We are in trouble if there is a component clause, and
2571 -- either we do not know the alignment of the slice, or
2572 -- the alignment of the slice is inconsistent with the
2573 -- bit position specified by the component clause.
2574
2575 declare
2576 Field : constant Entity_Id := Entity (Selector_Name (Pref));
2577 begin
2578 if Present (Component_Clause (Field))
2579 and then
2580 (Unknown_Alignment (Styp)
2581 or else
2582 (Component_Bit_Offset (Field) mod
2583 (System_Storage_Unit * Alignment (Styp))) /= 0)
2584 then
2585 return True;
2586 end if;
2587 end;
2588
2589 -- For cases other than selected or indexed components we
2590 -- know we are OK, since no issues arise over alignment.
2591
2592 else
2593 return False;
2594 end if;
2595
2596 -- We processed an indexed component or selected component
2597 -- reference that looked safe, so keep checking prefixes.
2598
2599 Pref := Prefix (Pref);
2600 end loop;
2601 end;
2602 end Is_Possibly_Unaligned_Slice;
2603
2604 --------------------------------
2605 -- Is_Ref_To_Bit_Packed_Array --
2606 --------------------------------
2607
2608 function Is_Ref_To_Bit_Packed_Array (N : Node_Id) return Boolean is
2609 Result : Boolean;
2610 Expr : Node_Id;
2611
2612 begin
2613 if Is_Entity_Name (N)
2614 and then Is_Object (Entity (N))
2615 and then Present (Renamed_Object (Entity (N)))
2616 then
2617 return Is_Ref_To_Bit_Packed_Array (Renamed_Object (Entity (N)));
2618 end if;
2619
2620 if Nkind (N) = N_Indexed_Component
2621 or else
2622 Nkind (N) = N_Selected_Component
2623 then
2624 if Is_Bit_Packed_Array (Etype (Prefix (N))) then
2625 Result := True;
2626 else
2627 Result := Is_Ref_To_Bit_Packed_Array (Prefix (N));
2628 end if;
2629
2630 if Result and then Nkind (N) = N_Indexed_Component then
2631 Expr := First (Expressions (N));
2632 while Present (Expr) loop
2633 Force_Evaluation (Expr);
2634 Next (Expr);
2635 end loop;
2636 end if;
2637
2638 return Result;
2639
2640 else
2641 return False;
2642 end if;
2643 end Is_Ref_To_Bit_Packed_Array;
2644
2645 --------------------------------
2646 -- Is_Ref_To_Bit_Packed_Slice --
2647 --------------------------------
2648
2649 function Is_Ref_To_Bit_Packed_Slice (N : Node_Id) return Boolean is
2650 begin
2651 if Is_Entity_Name (N)
2652 and then Is_Object (Entity (N))
2653 and then Present (Renamed_Object (Entity (N)))
2654 then
2655 return Is_Ref_To_Bit_Packed_Slice (Renamed_Object (Entity (N)));
2656 end if;
2657
2658 if Nkind (N) = N_Slice
2659 and then Is_Bit_Packed_Array (Etype (Prefix (N)))
2660 then
2661 return True;
2662
2663 elsif Nkind (N) = N_Indexed_Component
2664 or else
2665 Nkind (N) = N_Selected_Component
2666 then
2667 return Is_Ref_To_Bit_Packed_Slice (Prefix (N));
2668
2669 else
2670 return False;
2671 end if;
2672 end Is_Ref_To_Bit_Packed_Slice;
2673
2674 -----------------------
2675 -- Is_Renamed_Object --
2676 -----------------------
2677
2678 function Is_Renamed_Object (N : Node_Id) return Boolean is
2679 Pnod : constant Node_Id := Parent (N);
2680 Kind : constant Node_Kind := Nkind (Pnod);
2681
2682 begin
2683 if Kind = N_Object_Renaming_Declaration then
2684 return True;
2685
2686 elsif Kind = N_Indexed_Component
2687 or else Kind = N_Selected_Component
2688 then
2689 return Is_Renamed_Object (Pnod);
2690
2691 else
2692 return False;
2693 end if;
2694 end Is_Renamed_Object;
2695
2696 ----------------------------
2697 -- Is_Untagged_Derivation --
2698 ----------------------------
2699
2700 function Is_Untagged_Derivation (T : Entity_Id) return Boolean is
2701 begin
2702 return (not Is_Tagged_Type (T) and then Is_Derived_Type (T))
2703 or else
2704 (Is_Private_Type (T) and then Present (Full_View (T))
2705 and then not Is_Tagged_Type (Full_View (T))
2706 and then Is_Derived_Type (Full_View (T))
2707 and then Etype (Full_View (T)) /= T);
2708
2709 end Is_Untagged_Derivation;
2710
2711 --------------------
2712 -- Kill_Dead_Code --
2713 --------------------
2714
2715 procedure Kill_Dead_Code (N : Node_Id) is
2716 begin
2717 if Present (N) then
2718 Remove_Handler_Entries (N);
2719 Remove_Warning_Messages (N);
2720
2721 -- Recurse into block statements and bodies to process declarations
2722 -- and statements
2723
2724 if Nkind (N) = N_Block_Statement
2725 or else Nkind (N) = N_Subprogram_Body
2726 or else Nkind (N) = N_Package_Body
2727 then
2728 Kill_Dead_Code (Declarations (N));
2729 Kill_Dead_Code (Statements (Handled_Statement_Sequence (N)));
2730
2731 if Nkind (N) = N_Subprogram_Body then
2732 Set_Is_Eliminated (Defining_Entity (N));
2733 end if;
2734
2735 elsif Nkind (N) = N_Package_Declaration then
2736 Kill_Dead_Code (Visible_Declarations (Specification (N)));
2737 Kill_Dead_Code (Private_Declarations (Specification (N)));
2738
2739 declare
2740 E : Entity_Id := First_Entity (Defining_Entity (N));
2741 begin
2742 while Present (E) loop
2743 if Ekind (E) = E_Operator then
2744 Set_Is_Eliminated (E);
2745 end if;
2746
2747 Next_Entity (E);
2748 end loop;
2749 end;
2750
2751 -- Recurse into composite statement to kill individual statements,
2752 -- in particular instantiations.
2753
2754 elsif Nkind (N) = N_If_Statement then
2755 Kill_Dead_Code (Then_Statements (N));
2756 Kill_Dead_Code (Elsif_Parts (N));
2757 Kill_Dead_Code (Else_Statements (N));
2758
2759 elsif Nkind (N) = N_Loop_Statement then
2760 Kill_Dead_Code (Statements (N));
2761
2762 elsif Nkind (N) = N_Case_Statement then
2763 declare
2764 Alt : Node_Id;
2765 begin
2766 Alt := First (Alternatives (N));
2767 while Present (Alt) loop
2768 Kill_Dead_Code (Statements (Alt));
2769 Next (Alt);
2770 end loop;
2771 end;
2772
2773 elsif Nkind (N) = N_Case_Statement_Alternative then
2774 Kill_Dead_Code (Statements (N));
2775
2776 -- Deal with dead instances caused by deleting instantiations
2777
2778 elsif Nkind (N) in N_Generic_Instantiation then
2779 Remove_Dead_Instance (N);
2780 end if;
2781
2782 Delete_Tree (N);
2783 end if;
2784 end Kill_Dead_Code;
2785
2786 -- Case where argument is a list of nodes to be killed
2787
2788 procedure Kill_Dead_Code (L : List_Id) is
2789 N : Node_Id;
2790
2791 begin
2792 if Is_Non_Empty_List (L) then
2793 loop
2794 N := Remove_Head (L);
2795 exit when No (N);
2796 Kill_Dead_Code (N);
2797 end loop;
2798 end if;
2799 end Kill_Dead_Code;
2800
2801 ------------------------
2802 -- Known_Non_Negative --
2803 ------------------------
2804
2805 function Known_Non_Negative (Opnd : Node_Id) return Boolean is
2806 begin
2807 if Is_OK_Static_Expression (Opnd)
2808 and then Expr_Value (Opnd) >= 0
2809 then
2810 return True;
2811
2812 else
2813 declare
2814 Lo : constant Node_Id := Type_Low_Bound (Etype (Opnd));
2815
2816 begin
2817 return
2818 Is_OK_Static_Expression (Lo) and then Expr_Value (Lo) >= 0;
2819 end;
2820 end if;
2821 end Known_Non_Negative;
2822
2823 --------------------
2824 -- Known_Non_Null --
2825 --------------------
2826
2827 function Known_Non_Null (N : Node_Id) return Boolean is
2828 begin
2829 pragma Assert (Is_Access_Type (Underlying_Type (Etype (N))));
2830
2831 -- Case of entity for which Is_Known_Non_Null is True
2832
2833 if Is_Entity_Name (N) and then Is_Known_Non_Null (Entity (N)) then
2834
2835 -- If the entity is aliased or volatile, then we decide that
2836 -- we don't know it is really non-null even if the sequential
2837 -- flow indicates that it is, since such variables can be
2838 -- changed without us noticing.
2839
2840 if Is_Aliased (Entity (N))
2841 or else Treat_As_Volatile (Entity (N))
2842 then
2843 return False;
2844
2845 -- For all other cases, the flag is decisive
2846
2847 else
2848 return True;
2849 end if;
2850
2851 -- True if access attribute
2852
2853 elsif Nkind (N) = N_Attribute_Reference
2854 and then (Attribute_Name (N) = Name_Access
2855 or else
2856 Attribute_Name (N) = Name_Unchecked_Access
2857 or else
2858 Attribute_Name (N) = Name_Unrestricted_Access)
2859 then
2860 return True;
2861
2862 -- True if allocator
2863
2864 elsif Nkind (N) = N_Allocator then
2865 return True;
2866
2867 -- For a conversion, true if expression is known non-null
2868
2869 elsif Nkind (N) = N_Type_Conversion then
2870 return Known_Non_Null (Expression (N));
2871
2872 -- One more case is when Current_Value references a condition
2873 -- that ensures a non-null value.
2874
2875 elsif Is_Entity_Name (N) then
2876 declare
2877 Op : Node_Kind;
2878 Val : Node_Id;
2879
2880 begin
2881 Get_Current_Value_Condition (N, Op, Val);
2882 return Op = N_Op_Ne and then Nkind (Val) = N_Null;
2883 end;
2884
2885 -- Above are all cases where the value could be determined to be
2886 -- non-null. In all other cases, we don't know, so return False.
2887
2888 else
2889 return False;
2890 end if;
2891 end Known_Non_Null;
2892
2893 -----------------------------
2894 -- Make_CW_Equivalent_Type --
2895 -----------------------------
2896
2897 -- Create a record type used as an equivalent of any member
2898 -- of the class which takes its size from exp.
2899
2900 -- Generate the following code:
2901
2902 -- type Equiv_T is record
2903 -- _parent : T (List of discriminant constaints taken from Exp);
2904 -- Ext__50 : Storage_Array (1 .. (Exp'size - Typ'object_size)/8);
2905 -- end Equiv_T;
2906 --
2907 -- ??? Note that this type does not guarantee same alignment as all
2908 -- derived types
2909
2910 function Make_CW_Equivalent_Type
2911 (T : Entity_Id;
2912 E : Node_Id) return Entity_Id
2913 is
2914 Loc : constant Source_Ptr := Sloc (E);
2915 Root_Typ : constant Entity_Id := Root_Type (T);
2916 List_Def : constant List_Id := Empty_List;
2917 Equiv_Type : Entity_Id;
2918 Range_Type : Entity_Id;
2919 Str_Type : Entity_Id;
2920 Constr_Root : Entity_Id;
2921 Sizexpr : Node_Id;
2922
2923 begin
2924 if not Has_Discriminants (Root_Typ) then
2925 Constr_Root := Root_Typ;
2926 else
2927 Constr_Root :=
2928 Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
2929
2930 -- subtype cstr__n is T (List of discr constraints taken from Exp)
2931
2932 Append_To (List_Def,
2933 Make_Subtype_Declaration (Loc,
2934 Defining_Identifier => Constr_Root,
2935 Subtype_Indication =>
2936 Make_Subtype_From_Expr (E, Root_Typ)));
2937 end if;
2938
2939 -- subtype rg__xx is Storage_Offset range
2940 -- (Expr'size - typ'size) / Storage_Unit
2941
2942 Range_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('G'));
2943
2944 Sizexpr :=
2945 Make_Op_Subtract (Loc,
2946 Left_Opnd =>
2947 Make_Attribute_Reference (Loc,
2948 Prefix =>
2949 OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)),
2950 Attribute_Name => Name_Size),
2951 Right_Opnd =>
2952 Make_Attribute_Reference (Loc,
2953 Prefix => New_Reference_To (Constr_Root, Loc),
2954 Attribute_Name => Name_Object_Size));
2955
2956 Set_Paren_Count (Sizexpr, 1);
2957
2958 Append_To (List_Def,
2959 Make_Subtype_Declaration (Loc,
2960 Defining_Identifier => Range_Type,
2961 Subtype_Indication =>
2962 Make_Subtype_Indication (Loc,
2963 Subtype_Mark => New_Reference_To (RTE (RE_Storage_Offset), Loc),
2964 Constraint => Make_Range_Constraint (Loc,
2965 Range_Expression =>
2966 Make_Range (Loc,
2967 Low_Bound => Make_Integer_Literal (Loc, 1),
2968 High_Bound =>
2969 Make_Op_Divide (Loc,
2970 Left_Opnd => Sizexpr,
2971 Right_Opnd => Make_Integer_Literal (Loc,
2972 Intval => System_Storage_Unit)))))));
2973
2974 -- subtype str__nn is Storage_Array (rg__x);
2975
2976 Str_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
2977 Append_To (List_Def,
2978 Make_Subtype_Declaration (Loc,
2979 Defining_Identifier => Str_Type,
2980 Subtype_Indication =>
2981 Make_Subtype_Indication (Loc,
2982 Subtype_Mark => New_Reference_To (RTE (RE_Storage_Array), Loc),
2983 Constraint =>
2984 Make_Index_Or_Discriminant_Constraint (Loc,
2985 Constraints =>
2986 New_List (New_Reference_To (Range_Type, Loc))))));
2987
2988 -- type Equiv_T is record
2989 -- _parent : Tnn;
2990 -- E : Str_Type;
2991 -- end Equiv_T;
2992
2993 Equiv_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
2994
2995 -- When the target requires front-end layout, it's necessary to allow
2996 -- the equivalent type to be frozen so that layout can occur (when the
2997 -- associated class-wide subtype is frozen, the equivalent type will
2998 -- be frozen, see freeze.adb). For other targets, Gigi wants to have
2999 -- the equivalent type marked as frozen and deals with this type itself.
3000 -- In the Gigi case this will also avoid the generation of an init
3001 -- procedure for the type.
3002
3003 if not Frontend_Layout_On_Target then
3004 Set_Is_Frozen (Equiv_Type);
3005 end if;
3006
3007 Set_Ekind (Equiv_Type, E_Record_Type);
3008 Set_Parent_Subtype (Equiv_Type, Constr_Root);
3009
3010 Append_To (List_Def,
3011 Make_Full_Type_Declaration (Loc,
3012 Defining_Identifier => Equiv_Type,
3013
3014 Type_Definition =>
3015 Make_Record_Definition (Loc,
3016 Component_List => Make_Component_List (Loc,
3017 Component_Items => New_List (
3018 Make_Component_Declaration (Loc,
3019 Defining_Identifier =>
3020 Make_Defining_Identifier (Loc, Name_uParent),
3021 Component_Definition =>
3022 Make_Component_Definition (Loc,
3023 Aliased_Present => False,
3024 Subtype_Indication =>
3025 New_Reference_To (Constr_Root, Loc))),
3026
3027 Make_Component_Declaration (Loc,
3028 Defining_Identifier =>
3029 Make_Defining_Identifier (Loc,
3030 Chars => New_Internal_Name ('C')),
3031 Component_Definition =>
3032 Make_Component_Definition (Loc,
3033 Aliased_Present => False,
3034 Subtype_Indication =>
3035 New_Reference_To (Str_Type, Loc)))),
3036
3037 Variant_Part => Empty))));
3038
3039 Insert_Actions (E, List_Def);
3040 return Equiv_Type;
3041 end Make_CW_Equivalent_Type;
3042
3043 ------------------------
3044 -- Make_Literal_Range --
3045 ------------------------
3046
3047 function Make_Literal_Range
3048 (Loc : Source_Ptr;
3049 Literal_Typ : Entity_Id) return Node_Id
3050 is
3051 Lo : constant Node_Id :=
3052 New_Copy_Tree (String_Literal_Low_Bound (Literal_Typ));
3053
3054 begin
3055 Set_Analyzed (Lo, False);
3056
3057 return
3058 Make_Range (Loc,
3059 Low_Bound => Lo,
3060
3061 High_Bound =>
3062 Make_Op_Subtract (Loc,
3063 Left_Opnd =>
3064 Make_Op_Add (Loc,
3065 Left_Opnd => New_Copy_Tree (Lo),
3066 Right_Opnd =>
3067 Make_Integer_Literal (Loc,
3068 String_Literal_Length (Literal_Typ))),
3069 Right_Opnd => Make_Integer_Literal (Loc, 1)));
3070 end Make_Literal_Range;
3071
3072 ----------------------------
3073 -- Make_Subtype_From_Expr --
3074 ----------------------------
3075
3076 -- 1. If Expr is an uncontrained array expression, creates
3077 -- Unc_Type(Expr'first(1)..Expr'Last(1),..., Expr'first(n)..Expr'last(n))
3078
3079 -- 2. If Expr is a unconstrained discriminated type expression, creates
3080 -- Unc_Type(Expr.Discr1, ... , Expr.Discr_n)
3081
3082 -- 3. If Expr is class-wide, creates an implicit class wide subtype
3083
3084 function Make_Subtype_From_Expr
3085 (E : Node_Id;
3086 Unc_Typ : Entity_Id) return Node_Id
3087 is
3088 Loc : constant Source_Ptr := Sloc (E);
3089 List_Constr : constant List_Id := New_List;
3090 D : Entity_Id;
3091
3092 Full_Subtyp : Entity_Id;
3093 Priv_Subtyp : Entity_Id;
3094 Utyp : Entity_Id;
3095 Full_Exp : Node_Id;
3096
3097 begin
3098 if Is_Private_Type (Unc_Typ)
3099 and then Has_Unknown_Discriminants (Unc_Typ)
3100 then
3101 -- Prepare the subtype completion, Go to base type to
3102 -- find underlying type.
3103
3104 Utyp := Underlying_Type (Base_Type (Unc_Typ));
3105 Full_Subtyp := Make_Defining_Identifier (Loc,
3106 New_Internal_Name ('C'));
3107 Full_Exp :=
3108 Unchecked_Convert_To
3109 (Utyp, Duplicate_Subexpr_No_Checks (E));
3110 Set_Parent (Full_Exp, Parent (E));
3111
3112 Priv_Subtyp :=
3113 Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
3114
3115 Insert_Action (E,
3116 Make_Subtype_Declaration (Loc,
3117 Defining_Identifier => Full_Subtyp,
3118 Subtype_Indication => Make_Subtype_From_Expr (Full_Exp, Utyp)));
3119
3120 -- Define the dummy private subtype
3121
3122 Set_Ekind (Priv_Subtyp, Subtype_Kind (Ekind (Unc_Typ)));
3123 Set_Etype (Priv_Subtyp, Unc_Typ);
3124 Set_Scope (Priv_Subtyp, Full_Subtyp);
3125 Set_Is_Constrained (Priv_Subtyp);
3126 Set_Is_Tagged_Type (Priv_Subtyp, Is_Tagged_Type (Unc_Typ));
3127 Set_Is_Itype (Priv_Subtyp);
3128 Set_Associated_Node_For_Itype (Priv_Subtyp, E);
3129
3130 if Is_Tagged_Type (Priv_Subtyp) then
3131 Set_Class_Wide_Type
3132 (Base_Type (Priv_Subtyp), Class_Wide_Type (Unc_Typ));
3133 Set_Primitive_Operations (Priv_Subtyp,
3134 Primitive_Operations (Unc_Typ));
3135 end if;
3136
3137 Set_Full_View (Priv_Subtyp, Full_Subtyp);
3138
3139 return New_Reference_To (Priv_Subtyp, Loc);
3140
3141 elsif Is_Array_Type (Unc_Typ) then
3142 for J in 1 .. Number_Dimensions (Unc_Typ) loop
3143 Append_To (List_Constr,
3144 Make_Range (Loc,
3145 Low_Bound =>
3146 Make_Attribute_Reference (Loc,
3147 Prefix => Duplicate_Subexpr_No_Checks (E),
3148 Attribute_Name => Name_First,
3149 Expressions => New_List (
3150 Make_Integer_Literal (Loc, J))),
3151
3152 High_Bound =>
3153 Make_Attribute_Reference (Loc,
3154 Prefix => Duplicate_Subexpr_No_Checks (E),
3155 Attribute_Name => Name_Last,
3156 Expressions => New_List (
3157 Make_Integer_Literal (Loc, J)))));
3158 end loop;
3159
3160 elsif Is_Class_Wide_Type (Unc_Typ) then
3161 declare
3162 CW_Subtype : Entity_Id;
3163 EQ_Typ : Entity_Id := Empty;
3164
3165 begin
3166 -- A class-wide equivalent type is not needed when Java_VM
3167 -- because the JVM back end handles the class-wide object
3168 -- initialization itself (and doesn't need or want the
3169 -- additional intermediate type to handle the assignment).
3170
3171 if Expander_Active and then not Java_VM then
3172 EQ_Typ := Make_CW_Equivalent_Type (Unc_Typ, E);
3173 end if;
3174
3175 CW_Subtype := New_Class_Wide_Subtype (Unc_Typ, E);
3176 Set_Equivalent_Type (CW_Subtype, EQ_Typ);
3177
3178 if Present (EQ_Typ) then
3179 Set_Is_Class_Wide_Equivalent_Type (EQ_Typ);
3180 end if;
3181
3182 Set_Cloned_Subtype (CW_Subtype, Base_Type (Unc_Typ));
3183
3184 return New_Occurrence_Of (CW_Subtype, Loc);
3185 end;
3186
3187 -- Comment needed (what case is this ???)
3188
3189 else
3190 D := First_Discriminant (Unc_Typ);
3191 while Present (D) loop
3192 Append_To (List_Constr,
3193 Make_Selected_Component (Loc,
3194 Prefix => Duplicate_Subexpr_No_Checks (E),
3195 Selector_Name => New_Reference_To (D, Loc)));
3196
3197 Next_Discriminant (D);
3198 end loop;
3199 end if;
3200
3201 return
3202 Make_Subtype_Indication (Loc,
3203 Subtype_Mark => New_Reference_To (Unc_Typ, Loc),
3204 Constraint =>
3205 Make_Index_Or_Discriminant_Constraint (Loc,
3206 Constraints => List_Constr));
3207 end Make_Subtype_From_Expr;
3208
3209 -----------------------------
3210 -- May_Generate_Large_Temp --
3211 -----------------------------
3212
3213 -- At the current time, the only types that we return False for (i.e.
3214 -- where we decide we know they cannot generate large temps) are ones
3215 -- where we know the size is 256 bits or less at compile time, and we
3216 -- are still not doing a thorough job on arrays and records ???
3217
3218 function May_Generate_Large_Temp (Typ : Entity_Id) return Boolean is
3219 begin
3220 if not Size_Known_At_Compile_Time (Typ) then
3221 return False;
3222
3223 elsif Esize (Typ) /= 0 and then Esize (Typ) <= 256 then
3224 return False;
3225
3226 elsif Is_Array_Type (Typ)
3227 and then Present (Packed_Array_Type (Typ))
3228 then
3229 return May_Generate_Large_Temp (Packed_Array_Type (Typ));
3230
3231 -- We could do more here to find other small types ???
3232
3233 else
3234 return True;
3235 end if;
3236 end May_Generate_Large_Temp;
3237
3238 ----------------------------
3239 -- New_Class_Wide_Subtype --
3240 ----------------------------
3241
3242 function New_Class_Wide_Subtype
3243 (CW_Typ : Entity_Id;
3244 N : Node_Id) return Entity_Id
3245 is
3246 Res : constant Entity_Id := Create_Itype (E_Void, N);
3247 Res_Name : constant Name_Id := Chars (Res);
3248 Res_Scope : constant Entity_Id := Scope (Res);
3249
3250 begin
3251 Copy_Node (CW_Typ, Res);
3252 Set_Sloc (Res, Sloc (N));
3253 Set_Is_Itype (Res);
3254 Set_Associated_Node_For_Itype (Res, N);
3255 Set_Is_Public (Res, False); -- By default, may be changed below.
3256 Set_Public_Status (Res);
3257 Set_Chars (Res, Res_Name);
3258 Set_Scope (Res, Res_Scope);
3259 Set_Ekind (Res, E_Class_Wide_Subtype);
3260 Set_Next_Entity (Res, Empty);
3261 Set_Etype (Res, Base_Type (CW_Typ));
3262
3263 -- For targets where front-end layout is required, reset the Is_Frozen
3264 -- status of the subtype to False (it can be implicitly set to true
3265 -- from the copy of the class-wide type). For other targets, Gigi
3266 -- doesn't want the class-wide subtype to go through the freezing
3267 -- process (though it's unclear why that causes problems and it would
3268 -- be nice to allow freezing to occur normally for all targets ???).
3269
3270 if Frontend_Layout_On_Target then
3271 Set_Is_Frozen (Res, False);
3272 end if;
3273
3274 Set_Freeze_Node (Res, Empty);
3275 return (Res);
3276 end New_Class_Wide_Subtype;
3277
3278 -------------------------
3279 -- Remove_Side_Effects --
3280 -------------------------
3281
3282 procedure Remove_Side_Effects
3283 (Exp : Node_Id;
3284 Name_Req : Boolean := False;
3285 Variable_Ref : Boolean := False)
3286 is
3287 Loc : constant Source_Ptr := Sloc (Exp);
3288 Exp_Type : constant Entity_Id := Etype (Exp);
3289 Svg_Suppress : constant Suppress_Array := Scope_Suppress;
3290 Def_Id : Entity_Id;
3291 Ref_Type : Entity_Id;
3292 Res : Node_Id;
3293 Ptr_Typ_Decl : Node_Id;
3294 New_Exp : Node_Id;
3295 E : Node_Id;
3296
3297 function Side_Effect_Free (N : Node_Id) return Boolean;
3298 -- Determines if the tree N represents an expression that is known
3299 -- not to have side effects, and for which no processing is required.
3300
3301 function Side_Effect_Free (L : List_Id) return Boolean;
3302 -- Determines if all elements of the list L are side effect free
3303
3304 function Safe_Prefixed_Reference (N : Node_Id) return Boolean;
3305 -- The argument N is a construct where the Prefix is dereferenced
3306 -- if it is a an access type and the result is a variable. The call
3307 -- returns True if the construct is side effect free (not considering
3308 -- side effects in other than the prefix which are to be tested by the
3309 -- caller).
3310
3311 function Within_In_Parameter (N : Node_Id) return Boolean;
3312 -- Determines if N is a subcomponent of a composite in-parameter.
3313 -- If so, N is not side-effect free when the actual is global and
3314 -- modifiable indirectly from within a subprogram, because it may
3315 -- be passed by reference. The front-end must be conservative here
3316 -- and assume that this may happen with any array or record type.
3317 -- On the other hand, we cannot create temporaries for all expressions
3318 -- for which this condition is true, for various reasons that might
3319 -- require clearing up ??? For example, descriminant references that
3320 -- appear out of place, or spurious type errors with class-wide
3321 -- expressions. As a result, we limit the transformation to loop
3322 -- bounds, which is so far the only case that requires it.
3323
3324 -----------------------------
3325 -- Safe_Prefixed_Reference --
3326 -----------------------------
3327
3328 function Safe_Prefixed_Reference (N : Node_Id) return Boolean is
3329 begin
3330 -- If prefix is not side effect free, definitely not safe
3331
3332 if not Side_Effect_Free (Prefix (N)) then
3333 return False;
3334
3335 -- If the prefix is of an access type that is not access-to-constant,
3336 -- then this construct is a variable reference, which means it is to
3337 -- be considered to have side effects if Variable_Ref is set True
3338 -- Exception is an access to an entity that is a constant or an
3339 -- in-parameter which does not come from source, and is the result
3340 -- of a previous removal of side-effects.
3341
3342 elsif Is_Access_Type (Etype (Prefix (N)))
3343 and then not Is_Access_Constant (Etype (Prefix (N)))
3344 and then Variable_Ref
3345 then
3346 if not Is_Entity_Name (Prefix (N)) then
3347 return False;
3348 else
3349 return Ekind (Entity (Prefix (N))) = E_Constant
3350 or else Ekind (Entity (Prefix (N))) = E_In_Parameter;
3351 end if;
3352
3353 -- The following test is the simplest way of solving a complex
3354 -- problem uncovered by BB08-010: Side effect on loop bound that
3355 -- is a subcomponent of a global variable:
3356 -- If a loop bound is a subcomponent of a global variable, a
3357 -- modification of that variable within the loop may incorrectly
3358 -- affect the execution of the loop.
3359
3360 elsif not
3361 (Nkind (Parent (Parent (N))) /= N_Loop_Parameter_Specification
3362 or else not Within_In_Parameter (Prefix (N)))
3363 then
3364 return False;
3365
3366 -- All other cases are side effect free
3367
3368 else
3369 return True;
3370 end if;
3371 end Safe_Prefixed_Reference;
3372
3373 ----------------------
3374 -- Side_Effect_Free --
3375 ----------------------
3376
3377 function Side_Effect_Free (N : Node_Id) return Boolean is
3378 begin
3379 -- Note on checks that could raise Constraint_Error. Strictly, if
3380 -- we take advantage of 11.6, these checks do not count as side
3381 -- effects. However, we would just as soon consider that they are
3382 -- side effects, since the backend CSE does not work very well on
3383 -- expressions which can raise Constraint_Error. On the other
3384 -- hand, if we do not consider them to be side effect free, then
3385 -- we get some awkward expansions in -gnato mode, resulting in
3386 -- code insertions at a point where we do not have a clear model
3387 -- for performing the insertions. See 4908-002/comment for details.
3388
3389 -- Special handling for entity names
3390
3391 if Is_Entity_Name (N) then
3392
3393 -- If the entity is a constant, it is definitely side effect
3394 -- free. Note that the test of Is_Variable (N) below might
3395 -- be expected to catch this case, but it does not, because
3396 -- this test goes to the original tree, and we may have
3397 -- already rewritten a variable node with a constant as
3398 -- a result of an earlier Force_Evaluation call.
3399
3400 if Ekind (Entity (N)) = E_Constant
3401 or else Ekind (Entity (N)) = E_In_Parameter
3402 then
3403 return True;
3404
3405 -- Functions are not side effect free
3406
3407 elsif Ekind (Entity (N)) = E_Function then
3408 return False;
3409
3410 -- Variables are considered to be a side effect if Variable_Ref
3411 -- is set or if we have a volatile variable and Name_Req is off.
3412 -- If Name_Req is True then we can't help returning a name which
3413 -- effectively allows multiple references in any case.
3414
3415 elsif Is_Variable (N) then
3416 return not Variable_Ref
3417 and then (not Treat_As_Volatile (Entity (N))
3418 or else Name_Req);
3419
3420 -- Any other entity (e.g. a subtype name) is definitely side
3421 -- effect free.
3422
3423 else
3424 return True;
3425 end if;
3426
3427 -- A value known at compile time is always side effect free
3428
3429 elsif Compile_Time_Known_Value (N) then
3430 return True;
3431 end if;
3432
3433 -- For other than entity names and compile time known values,
3434 -- check the node kind for special processing.
3435
3436 case Nkind (N) is
3437
3438 -- An attribute reference is side effect free if its expressions
3439 -- are side effect free and its prefix is side effect free or
3440 -- is an entity reference.
3441
3442 -- Is this right? what about x'first where x is a variable???
3443
3444 when N_Attribute_Reference =>
3445 return Side_Effect_Free (Expressions (N))
3446 and then (Is_Entity_Name (Prefix (N))
3447 or else Side_Effect_Free (Prefix (N)));
3448
3449 -- A binary operator is side effect free if and both operands
3450 -- are side effect free. For this purpose binary operators
3451 -- include membership tests and short circuit forms
3452
3453 when N_Binary_Op |
3454 N_In |
3455 N_Not_In |
3456 N_And_Then |
3457 N_Or_Else =>
3458 return Side_Effect_Free (Left_Opnd (N))
3459 and then Side_Effect_Free (Right_Opnd (N));
3460
3461 -- An explicit dereference is side effect free only if it is
3462 -- a side effect free prefixed reference.
3463
3464 when N_Explicit_Dereference =>
3465 return Safe_Prefixed_Reference (N);
3466
3467 -- A call to _rep_to_pos is side effect free, since we generate
3468 -- this pure function call ourselves. Moreover it is critically
3469 -- important to make this exception, since otherwise we can
3470 -- have discriminants in array components which don't look
3471 -- side effect free in the case of an array whose index type
3472 -- is an enumeration type with an enumeration rep clause.
3473
3474 -- All other function calls are not side effect free
3475
3476 when N_Function_Call =>
3477 return Nkind (Name (N)) = N_Identifier
3478 and then Is_TSS (Name (N), TSS_Rep_To_Pos)
3479 and then
3480 Side_Effect_Free (First (Parameter_Associations (N)));
3481
3482 -- An indexed component is side effect free if it is a side
3483 -- effect free prefixed reference and all the indexing
3484 -- expressions are side effect free.
3485
3486 when N_Indexed_Component =>
3487 return Side_Effect_Free (Expressions (N))
3488 and then Safe_Prefixed_Reference (N);
3489
3490 -- A type qualification is side effect free if the expression
3491 -- is side effect free.
3492
3493 when N_Qualified_Expression =>
3494 return Side_Effect_Free (Expression (N));
3495
3496 -- A selected component is side effect free only if it is a
3497 -- side effect free prefixed reference.
3498
3499 when N_Selected_Component =>
3500 return Safe_Prefixed_Reference (N);
3501
3502 -- A range is side effect free if the bounds are side effect free
3503
3504 when N_Range =>
3505 return Side_Effect_Free (Low_Bound (N))
3506 and then Side_Effect_Free (High_Bound (N));
3507
3508 -- A slice is side effect free if it is a side effect free
3509 -- prefixed reference and the bounds are side effect free.
3510
3511 when N_Slice =>
3512 return Side_Effect_Free (Discrete_Range (N))
3513 and then Safe_Prefixed_Reference (N);
3514
3515 -- A type conversion is side effect free if the expression
3516 -- to be converted is side effect free.
3517
3518 when N_Type_Conversion =>
3519 return Side_Effect_Free (Expression (N));
3520
3521 -- A unary operator is side effect free if the operand
3522 -- is side effect free.
3523
3524 when N_Unary_Op =>
3525 return Side_Effect_Free (Right_Opnd (N));
3526
3527 -- An unchecked type conversion is side effect free only if it
3528 -- is safe and its argument is side effect free.
3529
3530 when N_Unchecked_Type_Conversion =>
3531 return Safe_Unchecked_Type_Conversion (N)
3532 and then Side_Effect_Free (Expression (N));
3533
3534 -- An unchecked expression is side effect free if its expression
3535 -- is side effect free.
3536
3537 when N_Unchecked_Expression =>
3538 return Side_Effect_Free (Expression (N));
3539
3540 -- A literal is side effect free
3541
3542 when N_Character_Literal |
3543 N_Integer_Literal |
3544 N_Real_Literal |
3545 N_String_Literal =>
3546 return True;
3547
3548 -- We consider that anything else has side effects. This is a bit
3549 -- crude, but we are pretty close for most common cases, and we
3550 -- are certainly correct (i.e. we never return True when the
3551 -- answer should be False).
3552
3553 when others =>
3554 return False;
3555 end case;
3556 end Side_Effect_Free;
3557
3558 -- A list is side effect free if all elements of the list are
3559 -- side effect free.
3560
3561 function Side_Effect_Free (L : List_Id) return Boolean is
3562 N : Node_Id;
3563
3564 begin
3565 if L = No_List or else L = Error_List then
3566 return True;
3567
3568 else
3569 N := First (L);
3570 while Present (N) loop
3571 if not Side_Effect_Free (N) then
3572 return False;
3573 else
3574 Next (N);
3575 end if;
3576 end loop;
3577
3578 return True;
3579 end if;
3580 end Side_Effect_Free;
3581
3582 -------------------------
3583 -- Within_In_Parameter --
3584 -------------------------
3585
3586 function Within_In_Parameter (N : Node_Id) return Boolean is
3587 begin
3588 if not Comes_From_Source (N) then
3589 return False;
3590
3591 elsif Is_Entity_Name (N) then
3592 return
3593 Ekind (Entity (N)) = E_In_Parameter;
3594
3595 elsif Nkind (N) = N_Indexed_Component
3596 or else Nkind (N) = N_Selected_Component
3597 then
3598 return Within_In_Parameter (Prefix (N));
3599 else
3600
3601 return False;
3602 end if;
3603 end Within_In_Parameter;
3604
3605 -- Start of processing for Remove_Side_Effects
3606
3607 begin
3608 -- If we are side effect free already or expansion is disabled,
3609 -- there is nothing to do.
3610
3611 if Side_Effect_Free (Exp) or else not Expander_Active then
3612 return;
3613 end if;
3614
3615 -- All this must not have any checks
3616
3617 Scope_Suppress := (others => True);
3618
3619 -- If the expression has the form v.all then we can just capture
3620 -- the pointer, and then do an explicit dereference on the result.
3621
3622 if Nkind (Exp) = N_Explicit_Dereference then
3623 Def_Id :=
3624 Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
3625 Res :=
3626 Make_Explicit_Dereference (Loc, New_Reference_To (Def_Id, Loc));
3627
3628 Insert_Action (Exp,
3629 Make_Object_Declaration (Loc,
3630 Defining_Identifier => Def_Id,
3631 Object_Definition =>
3632 New_Reference_To (Etype (Prefix (Exp)), Loc),
3633 Constant_Present => True,
3634 Expression => Relocate_Node (Prefix (Exp))));
3635
3636 -- Similar processing for an unchecked conversion of an expression
3637 -- of the form v.all, where we want the same kind of treatment.
3638
3639 elsif Nkind (Exp) = N_Unchecked_Type_Conversion
3640 and then Nkind (Expression (Exp)) = N_Explicit_Dereference
3641 then
3642 Remove_Side_Effects (Expression (Exp), Name_Req, Variable_Ref);
3643 Scope_Suppress := Svg_Suppress;
3644 return;
3645
3646 -- If this is a type conversion, leave the type conversion and remove
3647 -- the side effects in the expression. This is important in several
3648 -- circumstances: for change of representations, and also when this
3649 -- is a view conversion to a smaller object, where gigi can end up
3650 -- creating its own temporary of the wrong size.
3651
3652 -- ??? this transformation is inhibited for elementary types that are
3653 -- not involved in a change of representation because it causes
3654 -- regressions that are not fully understood yet.
3655
3656 elsif Nkind (Exp) = N_Type_Conversion
3657 and then (not Is_Elementary_Type (Underlying_Type (Exp_Type))
3658 or else Nkind (Parent (Exp)) = N_Assignment_Statement)
3659 then
3660 Remove_Side_Effects (Expression (Exp), Name_Req, Variable_Ref);
3661 Scope_Suppress := Svg_Suppress;
3662 return;
3663
3664 -- For expressions that denote objects, we can use a renaming scheme.
3665 -- We skip using this if we have a volatile variable and we do not
3666 -- have Nam_Req set true (see comments above for Side_Effect_Free).
3667 -- We also skip this scheme for class-wide expressions in order to
3668 -- avoid recursive expansion (see Expand_N_Object_Renaming_Declaration)
3669 -- If the object is a function call, we need to create a temporary and
3670 -- not a renaming.
3671
3672 -- Note that we could use ordinary object declarations in the case of
3673 -- expressions not appearing as lvalues. That is left as a possible
3674 -- optimization in the future but we prefer to generate renamings
3675 -- right now, since we may indeed be transforming an lvalue.
3676
3677 elsif Is_Object_Reference (Exp)
3678 and then Nkind (Exp) /= N_Function_Call
3679 and then not Variable_Ref
3680 and then (Name_Req
3681 or else not Is_Entity_Name (Exp)
3682 or else not Treat_As_Volatile (Entity (Exp)))
3683 and then not Is_Class_Wide_Type (Exp_Type)
3684 then
3685 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
3686
3687 if Nkind (Exp) = N_Selected_Component
3688 and then Nkind (Prefix (Exp)) = N_Function_Call
3689 and then Is_Array_Type (Etype (Exp))
3690 then
3691 -- Avoid generating a variable-sized temporary, by generating
3692 -- the renaming declaration just for the function call. The
3693 -- transformation could be refined to apply only when the array
3694 -- component is constrained by a discriminant???
3695
3696 Res :=
3697 Make_Selected_Component (Loc,
3698 Prefix => New_Occurrence_Of (Def_Id, Loc),
3699 Selector_Name => Selector_Name (Exp));
3700
3701 Insert_Action (Exp,
3702 Make_Object_Renaming_Declaration (Loc,
3703 Defining_Identifier => Def_Id,
3704 Subtype_Mark =>
3705 New_Reference_To (Base_Type (Etype (Prefix (Exp))), Loc),
3706 Name => Relocate_Node (Prefix (Exp))));
3707
3708 -- The temporary must be elaborated by gigi, and is of course
3709 -- not to be replaced in-line by the expression it renames,
3710 -- which would defeat the purpose of removing the side-effect.
3711
3712 Set_Is_Renaming_Of_Object (Def_Id, False);
3713
3714 else
3715 Res := New_Reference_To (Def_Id, Loc);
3716
3717 Insert_Action (Exp,
3718 Make_Object_Renaming_Declaration (Loc,
3719 Defining_Identifier => Def_Id,
3720 Subtype_Mark => New_Reference_To (Exp_Type, Loc),
3721 Name => Relocate_Node (Exp)));
3722
3723 Set_Is_Renaming_Of_Object (Def_Id, False);
3724 end if;
3725
3726 -- If it is a scalar type, just make a copy
3727
3728 elsif Is_Elementary_Type (Exp_Type) then
3729 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
3730 Set_Etype (Def_Id, Exp_Type);
3731 Res := New_Reference_To (Def_Id, Loc);
3732
3733 E :=
3734 Make_Object_Declaration (Loc,
3735 Defining_Identifier => Def_Id,
3736 Object_Definition => New_Reference_To (Exp_Type, Loc),
3737 Constant_Present => True,
3738 Expression => Relocate_Node (Exp));
3739
3740 Set_Assignment_OK (E);
3741 Insert_Action (Exp, E);
3742
3743 -- Always use a renaming for an unchecked conversion
3744 -- If this is an unchecked conversion that Gigi can't handle, make
3745 -- a copy or a use a renaming to capture the value.
3746
3747 elsif Nkind (Exp) = N_Unchecked_Type_Conversion
3748 and then not Safe_Unchecked_Type_Conversion (Exp)
3749 then
3750 if Controlled_Type (Etype (Exp)) then
3751
3752 -- Use a renaming to capture the expression, rather than create
3753 -- a controlled temporary.
3754
3755 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
3756 Res := New_Reference_To (Def_Id, Loc);
3757
3758 Insert_Action (Exp,
3759 Make_Object_Renaming_Declaration (Loc,
3760 Defining_Identifier => Def_Id,
3761 Subtype_Mark => New_Reference_To (Exp_Type, Loc),
3762 Name => Relocate_Node (Exp)));
3763
3764 else
3765 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
3766 Set_Etype (Def_Id, Exp_Type);
3767 Res := New_Reference_To (Def_Id, Loc);
3768
3769 E :=
3770 Make_Object_Declaration (Loc,
3771 Defining_Identifier => Def_Id,
3772 Object_Definition => New_Reference_To (Exp_Type, Loc),
3773 Constant_Present => not Is_Variable (Exp),
3774 Expression => Relocate_Node (Exp));
3775
3776 Set_Assignment_OK (E);
3777 Insert_Action (Exp, E);
3778 end if;
3779
3780 -- Otherwise we generate a reference to the value
3781
3782 else
3783 Ref_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
3784
3785 Ptr_Typ_Decl :=
3786 Make_Full_Type_Declaration (Loc,
3787 Defining_Identifier => Ref_Type,
3788 Type_Definition =>
3789 Make_Access_To_Object_Definition (Loc,
3790 All_Present => True,
3791 Subtype_Indication =>
3792 New_Reference_To (Exp_Type, Loc)));
3793
3794 E := Exp;
3795 Insert_Action (Exp, Ptr_Typ_Decl);
3796
3797 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
3798 Set_Etype (Def_Id, Exp_Type);
3799
3800 Res :=
3801 Make_Explicit_Dereference (Loc,
3802 Prefix => New_Reference_To (Def_Id, Loc));
3803
3804 if Nkind (E) = N_Explicit_Dereference then
3805 New_Exp := Relocate_Node (Prefix (E));
3806 else
3807 E := Relocate_Node (E);
3808 New_Exp := Make_Reference (Loc, E);
3809 end if;
3810
3811 if Is_Delayed_Aggregate (E) then
3812
3813 -- The expansion of nested aggregates is delayed until the
3814 -- enclosing aggregate is expanded. As aggregates are often
3815 -- qualified, the predicate applies to qualified expressions
3816 -- as well, indicating that the enclosing aggregate has not
3817 -- been expanded yet. At this point the aggregate is part of
3818 -- a stand-alone declaration, and must be fully expanded.
3819
3820 if Nkind (E) = N_Qualified_Expression then
3821 Set_Expansion_Delayed (Expression (E), False);
3822 Set_Analyzed (Expression (E), False);
3823 else
3824 Set_Expansion_Delayed (E, False);
3825 end if;
3826
3827 Set_Analyzed (E, False);
3828 end if;
3829
3830 Insert_Action (Exp,
3831 Make_Object_Declaration (Loc,
3832 Defining_Identifier => Def_Id,
3833 Object_Definition => New_Reference_To (Ref_Type, Loc),
3834 Expression => New_Exp));
3835 end if;
3836
3837 -- Preserve the Assignment_OK flag in all copies, since at least
3838 -- one copy may be used in a context where this flag must be set
3839 -- (otherwise why would the flag be set in the first place).
3840
3841 Set_Assignment_OK (Res, Assignment_OK (Exp));
3842
3843 -- Finally rewrite the original expression and we are done
3844
3845 Rewrite (Exp, Res);
3846 Analyze_And_Resolve (Exp, Exp_Type);
3847 Scope_Suppress := Svg_Suppress;
3848 end Remove_Side_Effects;
3849
3850 ---------------------------
3851 -- Represented_As_Scalar --
3852 ---------------------------
3853
3854 function Represented_As_Scalar (T : Entity_Id) return Boolean is
3855 UT : constant Entity_Id := Underlying_Type (T);
3856 begin
3857 return Is_Scalar_Type (UT)
3858 or else (Is_Bit_Packed_Array (UT)
3859 and then Is_Scalar_Type (Packed_Array_Type (UT)));
3860 end Represented_As_Scalar;
3861
3862 ------------------------------------
3863 -- Safe_Unchecked_Type_Conversion --
3864 ------------------------------------
3865
3866 -- Note: this function knows quite a bit about the exact requirements
3867 -- of Gigi with respect to unchecked type conversions, and its code
3868 -- must be coordinated with any changes in Gigi in this area.
3869
3870 -- The above requirements should be documented in Sinfo ???
3871
3872 function Safe_Unchecked_Type_Conversion (Exp : Node_Id) return Boolean is
3873 Otyp : Entity_Id;
3874 Ityp : Entity_Id;
3875 Oalign : Uint;
3876 Ialign : Uint;
3877 Pexp : constant Node_Id := Parent (Exp);
3878
3879 begin
3880 -- If the expression is the RHS of an assignment or object declaration
3881 -- we are always OK because there will always be a target.
3882
3883 -- Object renaming declarations, (generated for view conversions of
3884 -- actuals in inlined calls), like object declarations, provide an
3885 -- explicit type, and are safe as well.
3886
3887 if (Nkind (Pexp) = N_Assignment_Statement
3888 and then Expression (Pexp) = Exp)
3889 or else Nkind (Pexp) = N_Object_Declaration
3890 or else Nkind (Pexp) = N_Object_Renaming_Declaration
3891 then
3892 return True;
3893
3894 -- If the expression is the prefix of an N_Selected_Component
3895 -- we should also be OK because GCC knows to look inside the
3896 -- conversion except if the type is discriminated. We assume
3897 -- that we are OK anyway if the type is not set yet or if it is
3898 -- controlled since we can't afford to introduce a temporary in
3899 -- this case.
3900
3901 elsif Nkind (Pexp) = N_Selected_Component
3902 and then Prefix (Pexp) = Exp
3903 then
3904 if No (Etype (Pexp)) then
3905 return True;
3906 else
3907 return
3908 not Has_Discriminants (Etype (Pexp))
3909 or else Is_Constrained (Etype (Pexp));
3910 end if;
3911 end if;
3912
3913 -- Set the output type, this comes from Etype if it is set, otherwise
3914 -- we take it from the subtype mark, which we assume was already
3915 -- fully analyzed.
3916
3917 if Present (Etype (Exp)) then
3918 Otyp := Etype (Exp);
3919 else
3920 Otyp := Entity (Subtype_Mark (Exp));
3921 end if;
3922
3923 -- The input type always comes from the expression, and we assume
3924 -- this is indeed always analyzed, so we can simply get the Etype.
3925
3926 Ityp := Etype (Expression (Exp));
3927
3928 -- Initialize alignments to unknown so far
3929
3930 Oalign := No_Uint;
3931 Ialign := No_Uint;
3932
3933 -- Replace a concurrent type by its corresponding record type
3934 -- and each type by its underlying type and do the tests on those.
3935 -- The original type may be a private type whose completion is a
3936 -- concurrent type, so find the underlying type first.
3937
3938 if Present (Underlying_Type (Otyp)) then
3939 Otyp := Underlying_Type (Otyp);
3940 end if;
3941
3942 if Present (Underlying_Type (Ityp)) then
3943 Ityp := Underlying_Type (Ityp);
3944 end if;
3945
3946 if Is_Concurrent_Type (Otyp) then
3947 Otyp := Corresponding_Record_Type (Otyp);
3948 end if;
3949
3950 if Is_Concurrent_Type (Ityp) then
3951 Ityp := Corresponding_Record_Type (Ityp);
3952 end if;
3953
3954 -- If the base types are the same, we know there is no problem since
3955 -- this conversion will be a noop.
3956
3957 if Implementation_Base_Type (Otyp) = Implementation_Base_Type (Ityp) then
3958 return True;
3959
3960 -- Same if this is an upwards conversion of an untagged type, and there
3961 -- are no constraints involved (could be more general???)
3962
3963 elsif Etype (Ityp) = Otyp
3964 and then not Is_Tagged_Type (Ityp)
3965 and then not Has_Discriminants (Ityp)
3966 and then No (First_Rep_Item (Base_Type (Ityp)))
3967 then
3968 return True;
3969
3970 -- If the size of output type is known at compile time, there is
3971 -- never a problem. Note that unconstrained records are considered
3972 -- to be of known size, but we can't consider them that way here,
3973 -- because we are talking about the actual size of the object.
3974
3975 -- We also make sure that in addition to the size being known, we do
3976 -- not have a case which might generate an embarrassingly large temp
3977 -- in stack checking mode.
3978
3979 elsif Size_Known_At_Compile_Time (Otyp)
3980 and then
3981 (not Stack_Checking_Enabled
3982 or else not May_Generate_Large_Temp (Otyp))
3983 and then not (Is_Record_Type (Otyp) and then not Is_Constrained (Otyp))
3984 then
3985 return True;
3986
3987 -- If either type is tagged, then we know the alignment is OK so
3988 -- Gigi will be able to use pointer punning.
3989
3990 elsif Is_Tagged_Type (Otyp) or else Is_Tagged_Type (Ityp) then
3991 return True;
3992
3993 -- If either type is a limited record type, we cannot do a copy, so
3994 -- say safe since there's nothing else we can do.
3995
3996 elsif Is_Limited_Record (Otyp) or else Is_Limited_Record (Ityp) then
3997 return True;
3998
3999 -- Conversions to and from packed array types are always ignored and
4000 -- hence are safe.
4001
4002 elsif Is_Packed_Array_Type (Otyp)
4003 or else Is_Packed_Array_Type (Ityp)
4004 then
4005 return True;
4006 end if;
4007
4008 -- The only other cases known to be safe is if the input type's
4009 -- alignment is known to be at least the maximum alignment for the
4010 -- target or if both alignments are known and the output type's
4011 -- alignment is no stricter than the input's. We can use the alignment
4012 -- of the component type of an array if a type is an unpacked
4013 -- array type.
4014
4015 if Present (Alignment_Clause (Otyp)) then
4016 Oalign := Expr_Value (Expression (Alignment_Clause (Otyp)));
4017
4018 elsif Is_Array_Type (Otyp)
4019 and then Present (Alignment_Clause (Component_Type (Otyp)))
4020 then
4021 Oalign := Expr_Value (Expression (Alignment_Clause
4022 (Component_Type (Otyp))));
4023 end if;
4024
4025 if Present (Alignment_Clause (Ityp)) then
4026 Ialign := Expr_Value (Expression (Alignment_Clause (Ityp)));
4027
4028 elsif Is_Array_Type (Ityp)
4029 and then Present (Alignment_Clause (Component_Type (Ityp)))
4030 then
4031 Ialign := Expr_Value (Expression (Alignment_Clause
4032 (Component_Type (Ityp))));
4033 end if;
4034
4035 if Ialign /= No_Uint and then Ialign > Maximum_Alignment then
4036 return True;
4037
4038 elsif Ialign /= No_Uint and then Oalign /= No_Uint
4039 and then Ialign <= Oalign
4040 then
4041 return True;
4042
4043 -- Otherwise, Gigi cannot handle this and we must make a temporary
4044
4045 else
4046 return False;
4047 end if;
4048
4049 end Safe_Unchecked_Type_Conversion;
4050
4051 --------------------------
4052 -- Set_Elaboration_Flag --
4053 --------------------------
4054
4055 procedure Set_Elaboration_Flag (N : Node_Id; Spec_Id : Entity_Id) is
4056 Loc : constant Source_Ptr := Sloc (N);
4057 Ent : constant Entity_Id := Elaboration_Entity (Spec_Id);
4058 Asn : Node_Id;
4059
4060 begin
4061 if Present (Ent) then
4062
4063 -- Nothing to do if at the compilation unit level, because in this
4064 -- case the flag is set by the binder generated elaboration routine.
4065
4066 if Nkind (Parent (N)) = N_Compilation_Unit then
4067 null;
4068
4069 -- Here we do need to generate an assignment statement
4070
4071 else
4072 Check_Restriction (No_Elaboration_Code, N);
4073 Asn :=
4074 Make_Assignment_Statement (Loc,
4075 Name => New_Occurrence_Of (Ent, Loc),
4076 Expression => New_Occurrence_Of (Standard_True, Loc));
4077
4078 if Nkind (Parent (N)) = N_Subunit then
4079 Insert_After (Corresponding_Stub (Parent (N)), Asn);
4080 else
4081 Insert_After (N, Asn);
4082 end if;
4083
4084 Analyze (Asn);
4085
4086 -- Kill current value indication. This is necessary because
4087 -- the tests of this flag are inserted out of sequence and must
4088 -- not pick up bogus indications of the wrong constant value.
4089
4090 Set_Current_Value (Ent, Empty);
4091 end if;
4092 end if;
4093 end Set_Elaboration_Flag;
4094
4095 --------------------------
4096 -- Target_Has_Fixed_Ops --
4097 --------------------------
4098
4099 Integer_Sized_Small : Ureal;
4100 -- Set to 2.0 ** -(Integer'Size - 1) the first time that this
4101 -- function is called (we don't want to compute it more than once!)
4102
4103 Long_Integer_Sized_Small : Ureal;
4104 -- Set to 2.0 ** -(Long_Integer'Size - 1) the first time that this
4105 -- functoin is called (we don't want to compute it more than once)
4106
4107 First_Time_For_THFO : Boolean := True;
4108 -- Set to False after first call (if Fractional_Fixed_Ops_On_Target)
4109
4110 function Target_Has_Fixed_Ops
4111 (Left_Typ : Entity_Id;
4112 Right_Typ : Entity_Id;
4113 Result_Typ : Entity_Id) return Boolean
4114 is
4115 function Is_Fractional_Type (Typ : Entity_Id) return Boolean;
4116 -- Return True if the given type is a fixed-point type with a small
4117 -- value equal to 2 ** (-(T'Object_Size - 1)) and whose values have
4118 -- an absolute value less than 1.0. This is currently limited
4119 -- to fixed-point types that map to Integer or Long_Integer.
4120
4121 ------------------------
4122 -- Is_Fractional_Type --
4123 ------------------------
4124
4125 function Is_Fractional_Type (Typ : Entity_Id) return Boolean is
4126 begin
4127 if Esize (Typ) = Standard_Integer_Size then
4128 return Small_Value (Typ) = Integer_Sized_Small;
4129
4130 elsif Esize (Typ) = Standard_Long_Integer_Size then
4131 return Small_Value (Typ) = Long_Integer_Sized_Small;
4132
4133 else
4134 return False;
4135 end if;
4136 end Is_Fractional_Type;
4137
4138 -- Start of processing for Target_Has_Fixed_Ops
4139
4140 begin
4141 -- Return False if Fractional_Fixed_Ops_On_Target is false
4142
4143 if not Fractional_Fixed_Ops_On_Target then
4144 return False;
4145 end if;
4146
4147 -- Here the target has Fractional_Fixed_Ops, if first time, compute
4148 -- standard constants used by Is_Fractional_Type.
4149
4150 if First_Time_For_THFO then
4151 First_Time_For_THFO := False;
4152
4153 Integer_Sized_Small :=
4154 UR_From_Components
4155 (Num => Uint_1,
4156 Den => UI_From_Int (Standard_Integer_Size - 1),
4157 Rbase => 2);
4158
4159 Long_Integer_Sized_Small :=
4160 UR_From_Components
4161 (Num => Uint_1,
4162 Den => UI_From_Int (Standard_Long_Integer_Size - 1),
4163 Rbase => 2);
4164 end if;
4165
4166 -- Return True if target supports fixed-by-fixed multiply/divide
4167 -- for fractional fixed-point types (see Is_Fractional_Type) and
4168 -- the operand and result types are equivalent fractional types.
4169
4170 return Is_Fractional_Type (Base_Type (Left_Typ))
4171 and then Is_Fractional_Type (Base_Type (Right_Typ))
4172 and then Is_Fractional_Type (Base_Type (Result_Typ))
4173 and then Esize (Left_Typ) = Esize (Right_Typ)
4174 and then Esize (Left_Typ) = Esize (Result_Typ);
4175 end Target_Has_Fixed_Ops;
4176
4177 ------------------------------------------
4178 -- Type_May_Have_Bit_Aligned_Components --
4179 ------------------------------------------
4180
4181 function Type_May_Have_Bit_Aligned_Components
4182 (Typ : Entity_Id) return Boolean
4183 is
4184 begin
4185 -- Array type, check component type
4186
4187 if Is_Array_Type (Typ) then
4188 return
4189 Type_May_Have_Bit_Aligned_Components (Component_Type (Typ));
4190
4191 -- Record type, check components
4192
4193 elsif Is_Record_Type (Typ) then
4194 declare
4195 E : Entity_Id;
4196
4197 begin
4198 E := First_Entity (Typ);
4199 while Present (E) loop
4200 if Ekind (E) = E_Component
4201 or else Ekind (E) = E_Discriminant
4202 then
4203 if Component_May_Be_Bit_Aligned (E)
4204 or else
4205 Type_May_Have_Bit_Aligned_Components (Etype (E))
4206 then
4207 return True;
4208 end if;
4209 end if;
4210
4211 Next_Entity (E);
4212 end loop;
4213
4214 return False;
4215 end;
4216
4217 -- Type other than array or record is always OK
4218
4219 else
4220 return False;
4221 end if;
4222 end Type_May_Have_Bit_Aligned_Components;
4223
4224 ----------------------------
4225 -- Wrap_Cleanup_Procedure --
4226 ----------------------------
4227
4228 procedure Wrap_Cleanup_Procedure (N : Node_Id) is
4229 Loc : constant Source_Ptr := Sloc (N);
4230 Stseq : constant Node_Id := Handled_Statement_Sequence (N);
4231 Stmts : constant List_Id := Statements (Stseq);
4232
4233 begin
4234 if Abort_Allowed then
4235 Prepend_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Defer));
4236 Append_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Undefer));
4237 end if;
4238 end Wrap_Cleanup_Procedure;
4239
4240 end Exp_Util;
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