]> gcc.gnu.org Git - gcc.git/blame - gcc/ada/exp_util.adb
git://gcc.gnu.org / gcc.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
re PR fortran/31547 (Document when CPP is called and document the f95-cpp-input option)
[gcc.git] / gcc / ada / exp_util.adb
CommitLineData
70482933
RK		 1------------------------------------------------------------------------------
2-- --
3-- GNAT COMPILER COMPONENTS --
4-- --
5-- E X P _ U T I L --
6-- --
7-- B o d y --
8-- --
0712790c 9-- Copyright (C) 1992-2007, Free Software Foundation, Inc. --
70482933
RK		 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 --
cb5fee25
KC		 19-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20-- Boston, MA 02110-1301, USA. --
70482933
RK		 21-- --
22-- GNAT was originally developed by the GNAT team at New York University. --
71ff80dc 23-- Extensive contributions were provided by Ada Core Technologies Inc. --
70482933
RK		 24-- --
25------------------------------------------------------------------------------
26
27with Atree; use Atree;
28with Checks; use Checks;
59e54267 29with Debug; use Debug;
70482933
RK		 30with Einfo; use Einfo;
31with Elists; use Elists;
32with Errout; use Errout;
f44fe430 33with Exp_Aggr; use Exp_Aggr;
86cde7b1 34with Exp_Ch6; use Exp_Ch6;
70482933 35with Exp_Ch7; use Exp_Ch7;
70482933
RK		 36with Inline; use Inline;
37with Itypes; use Itypes;
38with Lib; use Lib;
70482933
RK		 39with Nlists; use Nlists;
40with Nmake; use Nmake;
41with Opt; use Opt;
42with Restrict; use Restrict;
6e937c1c 43with Rident; use Rident;
70482933
RK		 44with Sem; use Sem;
45with Sem_Ch8; use Sem_Ch8;
46with Sem_Eval; use Sem_Eval;
47with Sem_Res; use Sem_Res;
758c442c 48with Sem_Type; use Sem_Type;
70482933 49with Sem_Util; use Sem_Util;
fbf5a39b 50with Snames; use Snames;
70482933
RK		 51with Stand; use Stand;
52with Stringt; use Stringt;
07fc65c4 53with Targparm; use Targparm;
70482933
RK		 54with Tbuild; use Tbuild;
55with Ttypes; use Ttypes;
56with Uintp; use Uintp;
07fc65c4 57with Urealp; use Urealp;
70482933
RK		 58with Validsw; use Validsw;
59
60package body Exp_Util is
61
62 -----------------------
63 -- Local Subprograms --
64 -----------------------
65
66 function Build_Task_Array_Image
67 (Loc : Source_Ptr;
68 Id_Ref : Node_Id;
7bc1c7df 69 A_Type : Entity_Id;
bebbff91 70 Dyn : Boolean := False) return Node_Id;
70482933
RK		 71 -- Build function to generate the image string for a task that is an
72 -- array component, concatenating the images of each index. To avoid
73 -- storage leaks, the string is built with successive slice assignments.
7bc1c7df
ES		 74 -- The flag Dyn indicates whether this is called for the initialization
75 -- procedure of an array of tasks, or for the name of a dynamically
76 -- created task that is assigned to an indexed component.
70482933
RK		 77
78 function Build_Task_Image_Function
79 (Loc : Source_Ptr;
80 Decls : List_Id;
81 Stats : List_Id;
bebbff91 82 Res : Entity_Id) return Node_Id;
70482933
RK		 83 -- Common processing for Task_Array_Image and Task_Record_Image.
84 -- Build function body that computes image.
85
86 procedure Build_Task_Image_Prefix
87 (Loc : Source_Ptr;
88 Len : out Entity_Id;
89 Res : out Entity_Id;
90 Pos : out Entity_Id;
91 Prefix : Entity_Id;
92 Sum : Node_Id;
86cde7b1
RD		 93 Decls : List_Id;
94 Stats : List_Id);
70482933
RK		 95 -- Common processing for Task_Array_Image and Task_Record_Image.
96 -- Create local variables and assign prefix of name to result string.
97
98 function Build_Task_Record_Image
99 (Loc : Source_Ptr;
100 Id_Ref : Node_Id;
bebbff91 101 Dyn : Boolean := False) return Node_Id;
70482933
RK		 102 -- Build function to generate the image string for a task that is a
103 -- record component. Concatenate name of variable with that of selector.
7bc1c7df
ES		 104 -- The flag Dyn indicates whether this is called for the initialization
105 -- procedure of record with task components, or for a dynamically
106 -- created task that is assigned to a selected component.
70482933
RK		 107
108 function Make_CW_Equivalent_Type
bebbff91
AC		 109 (T : Entity_Id;
110 E : Node_Id) return Entity_Id;
70482933
RK		 111 -- T is a class-wide type entity, E is the initial expression node that
112 -- constrains T in case such as: " X: T := E" or "new T'(E)"
113 -- This function returns the entity of the Equivalent type and inserts
114 -- on the fly the necessary declaration such as:
fbf5a39b 115 --
70482933
RK		 116 -- type anon is record
117 -- _parent : Root_Type (T); constrained with E discriminants (if any)
118 -- Extension : String (1 .. expr to match size of E);
119 -- end record;
120 --
121 -- This record is compatible with any object of the class of T thanks
122 -- to the first field and has the same size as E thanks to the second.
123
124 function Make_Literal_Range
125 (Loc : Source_Ptr;
bebbff91 126 Literal_Typ : Entity_Id) return Node_Id;
70482933 127 -- Produce a Range node whose bounds are:
f91b40db 128 -- Low_Bound (Literal_Type) ..
86cde7b1 129 -- Low_Bound (Literal_Type) + (Length (Literal_Typ) - 1)
70482933 130 -- this is used for expanding declarations like X : String := "sdfgdfg";
86cde7b1
RD		 131 --
132 -- If the index type of the target array is not integer, we generate:
133 -- Low_Bound (Literal_Type) ..
134 -- Literal_Type'Val
135 -- (Literal_Type'Pos (Low_Bound (Literal_Type))
136 -- + (Length (Literal_Typ) -1))
70482933
RK		 137
138 function New_Class_Wide_Subtype
139 (CW_Typ : Entity_Id;
bebbff91
AC		 140 N : Node_Id) return Entity_Id;
141 -- Create an implicit subtype of CW_Typ attached to node N
70482933
RK		 142
143 ----------------------
144 -- Adjust_Condition --
145 ----------------------
146
147 procedure Adjust_Condition (N : Node_Id) is
148 begin
149 if No (N) then
150 return;
151 end if;
152
153 declare
154 Loc : constant Source_Ptr := Sloc (N);
155 T : constant Entity_Id := Etype (N);
156 Ti : Entity_Id;
157
158 begin
159 -- For now, we simply ignore a call where the argument has no
160 -- type (probably case of unanalyzed condition), or has a type
161 -- that is not Boolean. This is because this is a pretty marginal
162 -- piece of functionality, and violations of these rules are
163 -- likely to be truly marginal (how much code uses Fortran Logical
164 -- as the barrier to a protected entry?) and we do not want to
165 -- blow up existing programs. We can change this to an assertion
166 -- after 3.12a is released ???
167
168 if No (T) or else not Is_Boolean_Type (T) then
169 return;
170 end if;
171
172 -- Apply validity checking if needed
173
174 if Validity_Checks_On and Validity_Check_Tests then
175 Ensure_Valid (N);
176 end if;
177
178 -- Immediate return if standard boolean, the most common case,
179 -- where nothing needs to be done.
180
181 if Base_Type (T) = Standard_Boolean then
182 return;
183 end if;
184
185 -- Case of zero/non-zero semantics or non-standard enumeration
186 -- representation. In each case, we rewrite the node as:
187
188 -- ityp!(N) /= False'Enum_Rep
189
190 -- where ityp is an integer type with large enough size to hold
191 -- any value of type T.
192
193 if Nonzero_Is_True (T) or else Has_Non_Standard_Rep (T) then
194 if Esize (T) <= Esize (Standard_Integer) then
195 Ti := Standard_Integer;
196 else
197 Ti := Standard_Long_Long_Integer;
198 end if;
199
200 Rewrite (N,
201 Make_Op_Ne (Loc,
202 Left_Opnd => Unchecked_Convert_To (Ti, N),
203 Right_Opnd =>
204 Make_Attribute_Reference (Loc,
205 Attribute_Name => Name_Enum_Rep,
206 Prefix =>
207 New_Occurrence_Of (First_Literal (T), Loc))));
208 Analyze_And_Resolve (N, Standard_Boolean);
209
210 else
211 Rewrite (N, Convert_To (Standard_Boolean, N));
212 Analyze_And_Resolve (N, Standard_Boolean);
213 end if;
214 end;
215 end Adjust_Condition;
216
217 ------------------------
218 -- Adjust_Result_Type --
219 ------------------------
220
221 procedure Adjust_Result_Type (N : Node_Id; T : Entity_Id) is
222 begin
223 -- Ignore call if current type is not Standard.Boolean
224
225 if Etype (N) /= Standard_Boolean then
226 return;
227 end if;
228
229 -- If result is already of correct type, nothing to do. Note that
230 -- this will get the most common case where everything has a type
231 -- of Standard.Boolean.
232
233 if Base_Type (T) = Standard_Boolean then
234 return;
235
236 else
237 declare
238 KP : constant Node_Kind := Nkind (Parent (N));
239
240 begin
241 -- If result is to be used as a Condition in the syntax, no need
242 -- to convert it back, since if it was changed to Standard.Boolean
243 -- using Adjust_Condition, that is just fine for this usage.
244
245 if KP in N_Raise_xxx_Error or else KP in N_Has_Condition then
246 return;
247
248 -- If result is an operand of another logical operation, no need
249 -- to reset its type, since Standard.Boolean is just fine, and
250 -- such operations always do Adjust_Condition on their operands.
251
252 elsif KP in N_Op_Boolean
253 or else KP = N_And_Then
254 or else KP = N_Or_Else
255 or else KP = N_Op_Not
256 then
257 return;
258
259 -- Otherwise we perform a conversion from the current type,
260 -- which must be Standard.Boolean, to the desired type.
261
262 else
263 Set_Analyzed (N);
264 Rewrite (N, Convert_To (T, N));
265 Analyze_And_Resolve (N, T);
266 end if;
267 end;
268 end if;
269 end Adjust_Result_Type;
270
271 --------------------------
272 -- Append_Freeze_Action --
273 --------------------------
274
275 procedure Append_Freeze_Action (T : Entity_Id; N : Node_Id) is
05350ac6 276 Fnode : Node_Id;
70482933
RK		 277
278 begin
279 Ensure_Freeze_Node (T);
280 Fnode := Freeze_Node (T);
281
59e54267 282 if No (Actions (Fnode)) then
70482933
RK		 283 Set_Actions (Fnode, New_List);
284 end if;
285
286 Append (N, Actions (Fnode));
287 end Append_Freeze_Action;
288
289 ---------------------------
290 -- Append_Freeze_Actions --
291 ---------------------------
292
293 procedure Append_Freeze_Actions (T : Entity_Id; L : List_Id) is
294 Fnode : constant Node_Id := Freeze_Node (T);
295
296 begin
297 if No (L) then
298 return;
299
300 else
301 if No (Actions (Fnode)) then
302 Set_Actions (Fnode, L);
303
304 else
305 Append_List (L, Actions (Fnode));
306 end if;
307
308 end if;
309 end Append_Freeze_Actions;
310
311 ------------------------
312 -- Build_Runtime_Call --
313 ------------------------
314
315 function Build_Runtime_Call (Loc : Source_Ptr; RE : RE_Id) return Node_Id is
316 begin
fbf5a39b
AC		 317 -- If entity is not available, we can skip making the call (this avoids
318 -- junk duplicated error messages in a number of cases).
319
320 if not RTE_Available (RE) then
321 return Make_Null_Statement (Loc);
322 else
323 return
324 Make_Procedure_Call_Statement (Loc,
325 Name => New_Reference_To (RTE (RE), Loc));
326 end if;
70482933
RK		 327 end Build_Runtime_Call;
328
15ce9ca2
AC		 329 ----------------------------
330 -- Build_Task_Array_Image --
331 ----------------------------
70482933
RK		 332
333 -- This function generates the body for a function that constructs the
334 -- image string for a task that is an array component. The function is
fbf5a39b 335 -- local to the init proc for the array type, and is called for each one
70482933
RK		 336 -- of the components. The constructed image has the form of an indexed
337 -- component, whose prefix is the outer variable of the array type.
338 -- The n-dimensional array type has known indices Index, Index2...
fbf5a39b 339 -- Id_Ref is an indexed component form created by the enclosing init proc.
70482933 340 -- Its successive indices are Val1, Val2,.. which are the loop variables
fbf5a39b 341 -- in the loops that call the individual task init proc on each component.
70482933
RK		 342
343 -- The generated function has the following structure:
344
fbf5a39b
AC		 345 -- function F return String is
346 -- Pref : string renames Task_Name;
347 -- T1 : String := Index1'Image (Val1);
70482933 348 -- ...
fbf5a39b
AC		 349 -- Tn : String := indexn'image (Valn);
350 -- Len : Integer := T1'Length + ... + Tn'Length + n + 1;
70482933 351 -- -- Len includes commas and the end parentheses.
fbf5a39b
AC		 352 -- Res : String (1..Len);
353 -- Pos : Integer := Pref'Length;
70482933
RK		 354 --
355 -- begin
7bc1c7df 356 -- Res (1 .. Pos) := Pref;
70482933
RK		 357 -- Pos := Pos + 1;
358 -- Res (Pos) := '(';
359 -- Pos := Pos + 1;
360 -- Res (Pos .. Pos + T1'Length - 1) := T1;
361 -- Pos := Pos + T1'Length;
362 -- Res (Pos) := '.';
363 -- Pos := Pos + 1;
364 -- ...
365 -- Res (Pos .. Pos + Tn'Length - 1) := Tn;
366 -- Res (Len) := ')';
367 --
fbf5a39b 368 -- return Res;
70482933
RK		 369 -- end F;
370 --
371 -- Needless to say, multidimensional arrays of tasks are rare enough
372 -- that the bulkiness of this code is not really a concern.
373
374 function Build_Task_Array_Image
375 (Loc : Source_Ptr;
376 Id_Ref : Node_Id;
7bc1c7df 377 A_Type : Entity_Id;
bebbff91 378 Dyn : Boolean := False) return Node_Id
70482933
RK		 379 is
380 Dims : constant Nat := Number_Dimensions (A_Type);
bebbff91 381 -- Number of dimensions for array of tasks
70482933
RK		 382
383 Temps : array (1 .. Dims) of Entity_Id;
bebbff91 384 -- Array of temporaries to hold string for each index
70482933
RK		 385
386 Indx : Node_Id;
387 -- Index expression
388
389 Len : Entity_Id;
390 -- Total length of generated name
391
392 Pos : Entity_Id;
393 -- Running index for substring assignments
394
7bc1c7df 395 Pref : Entity_Id;
70482933
RK		 396 -- Name of enclosing variable, prefix of resulting name
397
398 Res : Entity_Id;
399 -- String to hold result
400
401 Val : Node_Id;
402 -- Value of successive indices
403
404 Sum : Node_Id;
405 -- Expression to compute total size of string
406
407 T : Entity_Id;
408 -- Entity for name at one index position
409
86cde7b1
RD		 410 Decls : constant List_Id := New_List;
411 Stats : constant List_Id := New_List;
70482933
RK		 412
413 begin
7bc1c7df
ES		 414 Pref := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
415
416 -- For a dynamic task, the name comes from the target variable.
fbf5a39b 417 -- For a static one it is a formal of the enclosing init proc.
7bc1c7df
ES		 418
419 if Dyn then
420 Get_Name_String (Chars (Entity (Prefix (Id_Ref))));
fbf5a39b
AC		 421 Append_To (Decls,
422 Make_Object_Declaration (Loc,
423 Defining_Identifier => Pref,
424 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
425 Expression =>
bebbff91
AC		 426 Make_String_Literal (Loc,
427 Strval => String_From_Name_Buffer)));
fbf5a39b 428
7bc1c7df 429 else
fbf5a39b
AC		 430 Append_To (Decls,
431 Make_Object_Renaming_Declaration (Loc,
432 Defining_Identifier => Pref,
433 Subtype_Mark => New_Occurrence_Of (Standard_String, Loc),
434 Name => Make_Identifier (Loc, Name_uTask_Name)));
7bc1c7df 435 end if;
70482933 436
70482933
RK		 437 Indx := First_Index (A_Type);
438 Val := First (Expressions (Id_Ref));
439
440 for J in 1 .. Dims loop
441 T := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
442 Temps (J) := T;
443
444 Append_To (Decls,
445 Make_Object_Declaration (Loc,
446 Defining_Identifier => T,
447 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
448 Expression =>
449 Make_Attribute_Reference (Loc,
450 Attribute_Name => Name_Image,
451 Prefix =>
452 New_Occurrence_Of (Etype (Indx), Loc),
453 Expressions => New_List (
454 New_Copy_Tree (Val)))));
455
456 Next_Index (Indx);
457 Next (Val);
458 end loop;
459
460 Sum := Make_Integer_Literal (Loc, Dims + 1);
461
462 Sum :=
463 Make_Op_Add (Loc,
464 Left_Opnd => Sum,
465 Right_Opnd =>
466 Make_Attribute_Reference (Loc,
467 Attribute_Name => Name_Length,
468 Prefix =>
7bc1c7df 469 New_Occurrence_Of (Pref, Loc),
70482933
RK		 470 Expressions => New_List (Make_Integer_Literal (Loc, 1))));
471
472 for J in 1 .. Dims loop
473 Sum :=
474 Make_Op_Add (Loc,
475 Left_Opnd => Sum,
476 Right_Opnd =>
477 Make_Attribute_Reference (Loc,
478 Attribute_Name => Name_Length,
479 Prefix =>
480 New_Occurrence_Of (Temps (J), Loc),
481 Expressions => New_List (Make_Integer_Literal (Loc, 1))));
482 end loop;
483
7bc1c7df 484 Build_Task_Image_Prefix (Loc, Len, Res, Pos, Pref, Sum, Decls, Stats);
70482933
RK		 485
486 Set_Character_Literal_Name (Char_Code (Character'Pos ('(')));
487
488 Append_To (Stats,
489 Make_Assignment_Statement (Loc,
490 Name => Make_Indexed_Component (Loc,
491 Prefix => New_Occurrence_Of (Res, Loc),
492 Expressions => New_List (New_Occurrence_Of (Pos, Loc))),
493 Expression =>
494 Make_Character_Literal (Loc,
495 Chars => Name_Find,
496 Char_Literal_Value =>
82c80734 497 UI_From_Int (Character'Pos ('(')))));
70482933
RK		 498
499 Append_To (Stats,
500 Make_Assignment_Statement (Loc,
501 Name => New_Occurrence_Of (Pos, Loc),
502 Expression =>
503 Make_Op_Add (Loc,
504 Left_Opnd => New_Occurrence_Of (Pos, Loc),
505 Right_Opnd => Make_Integer_Literal (Loc, 1))));
506
507 for J in 1 .. Dims loop
508
509 Append_To (Stats,
510 Make_Assignment_Statement (Loc,
511 Name => Make_Slice (Loc,
512 Prefix => New_Occurrence_Of (Res, Loc),
513 Discrete_Range =>
514 Make_Range (Loc,
515 Low_Bound => New_Occurrence_Of (Pos, Loc),
516 High_Bound => Make_Op_Subtract (Loc,
517 Left_Opnd =>
518 Make_Op_Add (Loc,
519 Left_Opnd => New_Occurrence_Of (Pos, Loc),
520 Right_Opnd =>
521 Make_Attribute_Reference (Loc,
522 Attribute_Name => Name_Length,
523 Prefix =>
524 New_Occurrence_Of (Temps (J), Loc),
525 Expressions =>
526 New_List (Make_Integer_Literal (Loc, 1)))),
527 Right_Opnd => Make_Integer_Literal (Loc, 1)))),
528
529 Expression => New_Occurrence_Of (Temps (J), Loc)));
530
531 if J < Dims then
532 Append_To (Stats,
533 Make_Assignment_Statement (Loc,
534 Name => New_Occurrence_Of (Pos, Loc),
535 Expression =>
536 Make_Op_Add (Loc,
537 Left_Opnd => New_Occurrence_Of (Pos, Loc),
538 Right_Opnd =>
539 Make_Attribute_Reference (Loc,
540 Attribute_Name => Name_Length,
541 Prefix => New_Occurrence_Of (Temps (J), Loc),
542 Expressions =>
543 New_List (Make_Integer_Literal (Loc, 1))))));
544
545 Set_Character_Literal_Name (Char_Code (Character'Pos (',')));
546
547 Append_To (Stats,
548 Make_Assignment_Statement (Loc,
549 Name => Make_Indexed_Component (Loc,
550 Prefix => New_Occurrence_Of (Res, Loc),
551 Expressions => New_List (New_Occurrence_Of (Pos, Loc))),
552 Expression =>
553 Make_Character_Literal (Loc,
554 Chars => Name_Find,
555 Char_Literal_Value =>
82c80734 556 UI_From_Int (Character'Pos (',')))));
70482933
RK		 557
558 Append_To (Stats,
559 Make_Assignment_Statement (Loc,
560 Name => New_Occurrence_Of (Pos, Loc),
561 Expression =>
562 Make_Op_Add (Loc,
563 Left_Opnd => New_Occurrence_Of (Pos, Loc),
564 Right_Opnd => Make_Integer_Literal (Loc, 1))));
565 end if;
566 end loop;
567
568 Set_Character_Literal_Name (Char_Code (Character'Pos (')')));
569
570 Append_To (Stats,
571 Make_Assignment_Statement (Loc,
572 Name => Make_Indexed_Component (Loc,
573 Prefix => New_Occurrence_Of (Res, Loc),
574 Expressions => New_List (New_Occurrence_Of (Len, Loc))),
575 Expression =>
576 Make_Character_Literal (Loc,
577 Chars => Name_Find,
578 Char_Literal_Value =>
82c80734 579 UI_From_Int (Character'Pos (')')))));
70482933
RK		 580 return Build_Task_Image_Function (Loc, Decls, Stats, Res);
581 end Build_Task_Array_Image;
582
583 ----------------------------
584 -- Build_Task_Image_Decls --
585 ----------------------------
586
587 function Build_Task_Image_Decls
05350ac6
BD		 588 (Loc : Source_Ptr;
589 Id_Ref : Node_Id;
590 A_Type : Entity_Id;
591 In_Init_Proc : Boolean := False) return List_Id
70482933 592 is
fbf5a39b 593 Decls : constant List_Id := New_List;
7bc1c7df
ES		 594 T_Id : Entity_Id := Empty;
595 Decl : Node_Id;
7bc1c7df
ES		 596 Expr : Node_Id := Empty;
597 Fun : Node_Id := Empty;
598 Is_Dyn : constant Boolean :=
fbf5a39b
AC		 599 Nkind (Parent (Id_Ref)) = N_Assignment_Statement
600 and then
601 Nkind (Expression (Parent (Id_Ref))) = N_Allocator;
70482933
RK		 602
603 begin
fbf5a39b
AC		 604 -- If Discard_Names or No_Implicit_Heap_Allocations are in effect,
605 -- generate a dummy declaration only.
70482933 606
6e937c1c 607 if Restriction_Active (No_Implicit_Heap_Allocations)
fbf5a39b
AC		 608 or else Global_Discard_Names
609 then
610 T_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
611 Name_Len := 0;
70482933
RK		 612
613 return
614 New_List (
615 Make_Object_Declaration (Loc,
616 Defining_Identifier => T_Id,
fbf5a39b
AC		 617 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
618 Expression =>
bebbff91
AC		 619 Make_String_Literal (Loc,
620 Strval => String_From_Name_Buffer)));
70482933
RK		 621
622 else
623 if Nkind (Id_Ref) = N_Identifier
624 or else Nkind (Id_Ref) = N_Defining_Identifier
625 then
523456db
AC		 626 -- For a simple variable, the image of the task is built from
627 -- the name of the variable. To avoid possible conflict with
628 -- the anonymous type created for a single protected object,
629 -- add a numeric suffix.
70482933
RK		 630
631 T_Id :=
632 Make_Defining_Identifier (Loc,
523456db 633 New_External_Name (Chars (Id_Ref), 'T', 1));
70482933
RK		 634
635 Get_Name_String (Chars (Id_Ref));
636
bebbff91
AC		 637 Expr :=
638 Make_String_Literal (Loc,
639 Strval => String_From_Name_Buffer);
70482933
RK		 640
641 elsif Nkind (Id_Ref) = N_Selected_Component then
642 T_Id :=
643 Make_Defining_Identifier (Loc,
fbf5a39b 644 New_External_Name (Chars (Selector_Name (Id_Ref)), 'T'));
07fc65c4 645 Fun := Build_Task_Record_Image (Loc, Id_Ref, Is_Dyn);
70482933
RK		 646
647 elsif Nkind (Id_Ref) = N_Indexed_Component then
648 T_Id :=
649 Make_Defining_Identifier (Loc,
fbf5a39b 650 New_External_Name (Chars (A_Type), 'N'));
70482933 651
7bc1c7df 652 Fun := Build_Task_Array_Image (Loc, Id_Ref, A_Type, Is_Dyn);
70482933
RK		 653 end if;
654 end if;
655
656 if Present (Fun) then
657 Append (Fun, Decls);
fbf5a39b
AC		 658 Expr := Make_Function_Call (Loc,
659 Name => New_Occurrence_Of (Defining_Entity (Fun), Loc));
05350ac6 660
0712790c 661 if not In_Init_Proc and then VM_Target = No_VM then
05350ac6
BD		 662 Set_Uses_Sec_Stack (Defining_Entity (Fun));
663 end if;
70482933
RK		 664 end if;
665
666 Decl := Make_Object_Declaration (Loc,
667 Defining_Identifier => T_Id,
fbf5a39b
AC		 668 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
669 Constant_Present => True,
670 Expression => Expr);
70482933
RK		 671
672 Append (Decl, Decls);
673 return Decls;
674 end Build_Task_Image_Decls;
675
676 -------------------------------
677 -- Build_Task_Image_Function --
678 -------------------------------
679
680 function Build_Task_Image_Function
681 (Loc : Source_Ptr;
682 Decls : List_Id;
683 Stats : List_Id;
bebbff91 684 Res : Entity_Id) return Node_Id
70482933
RK		 685 is
686 Spec : Node_Id;
687
688 begin
689 Append_To (Stats,
86cde7b1 690 Make_Simple_Return_Statement (Loc,
fbf5a39b
AC		 691 Expression => New_Occurrence_Of (Res, Loc)));
692
693 Spec := Make_Function_Specification (Loc,
694 Defining_Unit_Name =>
695 Make_Defining_Identifier (Loc, New_Internal_Name ('F')),
10b93b2e 696 Result_Definition => New_Occurrence_Of (Standard_String, Loc));
fbf5a39b
AC		 697
698 -- Calls to 'Image use the secondary stack, which must be cleaned
699 -- up after the task name is built.
700
70482933
RK		 701 return Make_Subprogram_Body (Loc,
702 Specification => Spec,
703 Declarations => Decls,
704 Handled_Statement_Sequence =>
fbf5a39b 705 Make_Handled_Sequence_Of_Statements (Loc, Statements => Stats));
70482933
RK		 706 end Build_Task_Image_Function;
707
708 -----------------------------
709 -- Build_Task_Image_Prefix --
710 -----------------------------
711
712 procedure Build_Task_Image_Prefix
713 (Loc : Source_Ptr;
714 Len : out Entity_Id;
715 Res : out Entity_Id;
716 Pos : out Entity_Id;
717 Prefix : Entity_Id;
718 Sum : Node_Id;
86cde7b1
RD		 719 Decls : List_Id;
720 Stats : List_Id)
70482933
RK		 721 is
722 begin
723 Len := Make_Defining_Identifier (Loc, New_Internal_Name ('L'));
724
725 Append_To (Decls,
726 Make_Object_Declaration (Loc,
727 Defining_Identifier => Len,
728 Object_Definition => New_Occurrence_Of (Standard_Integer, Loc),
729 Expression => Sum));
730
731 Res := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
732
733 Append_To (Decls,
734 Make_Object_Declaration (Loc,
735 Defining_Identifier => Res,
736 Object_Definition =>
737 Make_Subtype_Indication (Loc,
738 Subtype_Mark => New_Occurrence_Of (Standard_String, Loc),
739 Constraint =>
740 Make_Index_Or_Discriminant_Constraint (Loc,
741 Constraints =>
742 New_List (
743 Make_Range (Loc,
744 Low_Bound => Make_Integer_Literal (Loc, 1),
745 High_Bound => New_Occurrence_Of (Len, Loc)))))));
746
747 Pos := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
748
749 Append_To (Decls,
750 Make_Object_Declaration (Loc,
751 Defining_Identifier => Pos,
752 Object_Definition => New_Occurrence_Of (Standard_Integer, Loc)));
753
754 -- Pos := Prefix'Length;
755
756 Append_To (Stats,
757 Make_Assignment_Statement (Loc,
758 Name => New_Occurrence_Of (Pos, Loc),
759 Expression =>
760 Make_Attribute_Reference (Loc,
761 Attribute_Name => Name_Length,
762 Prefix => New_Occurrence_Of (Prefix, Loc),
763 Expressions =>
764 New_List (Make_Integer_Literal (Loc, 1)))));
765
766 -- Res (1 .. Pos) := Prefix;
767
768 Append_To (Stats,
769 Make_Assignment_Statement (Loc,
770 Name => Make_Slice (Loc,
771 Prefix => New_Occurrence_Of (Res, Loc),
772 Discrete_Range =>
773 Make_Range (Loc,
774 Low_Bound => Make_Integer_Literal (Loc, 1),
775 High_Bound => New_Occurrence_Of (Pos, Loc))),
776
777 Expression => New_Occurrence_Of (Prefix, Loc)));
778
779 Append_To (Stats,
780 Make_Assignment_Statement (Loc,
781 Name => New_Occurrence_Of (Pos, Loc),
782 Expression =>
783 Make_Op_Add (Loc,
784 Left_Opnd => New_Occurrence_Of (Pos, Loc),
785 Right_Opnd => Make_Integer_Literal (Loc, 1))));
786 end Build_Task_Image_Prefix;
787
788 -----------------------------
789 -- Build_Task_Record_Image --
790 -----------------------------
791
792 function Build_Task_Record_Image
793 (Loc : Source_Ptr;
794 Id_Ref : Node_Id;
bebbff91 795 Dyn : Boolean := False) return Node_Id
70482933
RK		 796 is
797 Len : Entity_Id;
798 -- Total length of generated name
799
800 Pos : Entity_Id;
801 -- Index into result
802
803 Res : Entity_Id;
804 -- String to hold result
805
7bc1c7df 806 Pref : Entity_Id;
70482933
RK		 807 -- Name of enclosing variable, prefix of resulting name
808
809 Sum : Node_Id;
bebbff91 810 -- Expression to compute total size of string
70482933
RK		 811
812 Sel : Entity_Id;
813 -- Entity for selector name
814
86cde7b1
RD		 815 Decls : constant List_Id := New_List;
816 Stats : constant List_Id := New_List;
70482933
RK		 817
818 begin
7bc1c7df
ES		 819 Pref := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
820
821 -- For a dynamic task, the name comes from the target variable.
fbf5a39b 822 -- For a static one it is a formal of the enclosing init proc.
7bc1c7df
ES		 823
824 if Dyn then
825 Get_Name_String (Chars (Entity (Prefix (Id_Ref))));
fbf5a39b
AC		 826 Append_To (Decls,
827 Make_Object_Declaration (Loc,
828 Defining_Identifier => Pref,
829 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
830 Expression =>
bebbff91
AC		 831 Make_String_Literal (Loc,
832 Strval => String_From_Name_Buffer)));
fbf5a39b 833
7bc1c7df 834 else
fbf5a39b
AC		 835 Append_To (Decls,
836 Make_Object_Renaming_Declaration (Loc,
837 Defining_Identifier => Pref,
838 Subtype_Mark => New_Occurrence_Of (Standard_String, Loc),
839 Name => Make_Identifier (Loc, Name_uTask_Name)));
7bc1c7df 840 end if;
70482933 841
70482933
RK		 842 Sel := Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
843
844 Get_Name_String (Chars (Selector_Name (Id_Ref)));
845
846 Append_To (Decls,
847 Make_Object_Declaration (Loc,
848 Defining_Identifier => Sel,
849 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
850 Expression =>
bebbff91
AC		 851 Make_String_Literal (Loc,
852 Strval => String_From_Name_Buffer)));
70482933
RK		 853
854 Sum := Make_Integer_Literal (Loc, Nat (Name_Len + 1));
855
856 Sum :=
857 Make_Op_Add (Loc,
858 Left_Opnd => Sum,
859 Right_Opnd =>
860 Make_Attribute_Reference (Loc,
861 Attribute_Name => Name_Length,
862 Prefix =>
7bc1c7df 863 New_Occurrence_Of (Pref, Loc),
70482933
RK		 864 Expressions => New_List (Make_Integer_Literal (Loc, 1))));
865
7bc1c7df 866 Build_Task_Image_Prefix (Loc, Len, Res, Pos, Pref, Sum, Decls, Stats);
70482933
RK		 867
868 Set_Character_Literal_Name (Char_Code (Character'Pos ('.')));
869
870 -- Res (Pos) := '.';
871
872 Append_To (Stats,
873 Make_Assignment_Statement (Loc,
874 Name => Make_Indexed_Component (Loc,
875 Prefix => New_Occurrence_Of (Res, Loc),
876 Expressions => New_List (New_Occurrence_Of (Pos, Loc))),
877 Expression =>
878 Make_Character_Literal (Loc,
879 Chars => Name_Find,
880 Char_Literal_Value =>
82c80734 881 UI_From_Int (Character'Pos ('.')))));
70482933
RK		 882
883 Append_To (Stats,
884 Make_Assignment_Statement (Loc,
885 Name => New_Occurrence_Of (Pos, Loc),
886 Expression =>
887 Make_Op_Add (Loc,
888 Left_Opnd => New_Occurrence_Of (Pos, Loc),
889 Right_Opnd => Make_Integer_Literal (Loc, 1))));
890
891 -- Res (Pos .. Len) := Selector;
892
893 Append_To (Stats,
894 Make_Assignment_Statement (Loc,
895 Name => Make_Slice (Loc,
896 Prefix => New_Occurrence_Of (Res, Loc),
897 Discrete_Range =>
898 Make_Range (Loc,
899 Low_Bound => New_Occurrence_Of (Pos, Loc),
900 High_Bound => New_Occurrence_Of (Len, Loc))),
901 Expression => New_Occurrence_Of (Sel, Loc)));
902
903 return Build_Task_Image_Function (Loc, Decls, Stats, Res);
904 end Build_Task_Record_Image;
905
91b1417d
AC		 906 ----------------------------------
907 -- Component_May_Be_Bit_Aligned --
908 ----------------------------------
909
910 function Component_May_Be_Bit_Aligned (Comp : Entity_Id) return Boolean is
911 begin
912 -- If no component clause, then everything is fine, since the
913 -- back end never bit-misaligns by default, even if there is
914 -- a pragma Packed for the record.
915
916 if No (Component_Clause (Comp)) then
917 return False;
918 end if;
919
920 -- It is only array and record types that cause trouble
921
922 if not Is_Record_Type (Etype (Comp))
923 and then not Is_Array_Type (Etype (Comp))
924 then
925 return False;
926
927 -- If we know that we have a small (64 bits or less) record
928 -- or bit-packed array, then everything is fine, since the
929 -- back end can handle these cases correctly.
930
931 elsif Esize (Comp) <= 64
932 and then (Is_Record_Type (Etype (Comp))
933 or else Is_Bit_Packed_Array (Etype (Comp)))
934 then
935 return False;
936
937 -- Otherwise if the component is not byte aligned, we
938 -- know we have the nasty unaligned case.
939
940 elsif Normalized_First_Bit (Comp) /= Uint_0
941 or else Esize (Comp) mod System_Storage_Unit /= Uint_0
942 then
943 return True;
944
945 -- If we are large and byte aligned, then OK at this level
946
947 else
948 return False;
949 end if;
950 end Component_May_Be_Bit_Aligned;
951
70482933
RK		 952 -------------------------------
953 -- Convert_To_Actual_Subtype --
954 -------------------------------
955
956 procedure Convert_To_Actual_Subtype (Exp : Entity_Id) is
957 Act_ST : Entity_Id;
958
959 begin
960 Act_ST := Get_Actual_Subtype (Exp);
961
962 if Act_ST = Etype (Exp) then
963 return;
964
965 else
966 Rewrite (Exp,
967 Convert_To (Act_ST, Relocate_Node (Exp)));
968 Analyze_And_Resolve (Exp, Act_ST);
969 end if;
970 end Convert_To_Actual_Subtype;
971
972 -----------------------------------
973 -- Current_Sem_Unit_Declarations --
974 -----------------------------------
975
976 function Current_Sem_Unit_Declarations return List_Id is
977 U : Node_Id := Unit (Cunit (Current_Sem_Unit));
978 Decls : List_Id;
979
980 begin
981 -- If the current unit is a package body, locate the visible
982 -- declarations of the package spec.
983
984 if Nkind (U) = N_Package_Body then
985 U := Unit (Library_Unit (Cunit (Current_Sem_Unit)));
986 end if;
987
988 if Nkind (U) = N_Package_Declaration then
989 U := Specification (U);
990 Decls := Visible_Declarations (U);
991
992 if No (Decls) then
993 Decls := New_List;
994 Set_Visible_Declarations (U, Decls);
995 end if;
996
997 else
998 Decls := Declarations (U);
999
1000 if No (Decls) then
1001 Decls := New_List;
1002 Set_Declarations (U, Decls);
1003 end if;
1004 end if;
1005
1006 return Decls;
1007 end Current_Sem_Unit_Declarations;
1008
1009 -----------------------
1010 -- Duplicate_Subexpr --
1011 -----------------------
1012
1013 function Duplicate_Subexpr
1014 (Exp : Node_Id;
bebbff91 1015 Name_Req : Boolean := False) return Node_Id
70482933
RK		 1016 is
1017 begin
1018 Remove_Side_Effects (Exp, Name_Req);
1019 return New_Copy_Tree (Exp);
1020 end Duplicate_Subexpr;
1021
8cbb664e
MG		 1022 ---------------------------------
1023 -- Duplicate_Subexpr_No_Checks --
1024 ---------------------------------
1025
1026 function Duplicate_Subexpr_No_Checks
1027 (Exp : Node_Id;
bebbff91 1028 Name_Req : Boolean := False) return Node_Id
8cbb664e
MG		 1029 is
1030 New_Exp : Node_Id;
1031
1032 begin
1033 Remove_Side_Effects (Exp, Name_Req);
1034 New_Exp := New_Copy_Tree (Exp);
1035 Remove_Checks (New_Exp);
1036 return New_Exp;
1037 end Duplicate_Subexpr_No_Checks;
1038
1039 -----------------------------------
1040 -- Duplicate_Subexpr_Move_Checks --
1041 -----------------------------------
1042
1043 function Duplicate_Subexpr_Move_Checks
1044 (Exp : Node_Id;
bebbff91 1045 Name_Req : Boolean := False) return Node_Id
8cbb664e
MG		 1046 is
1047 New_Exp : Node_Id;
1048
1049 begin
1050 Remove_Side_Effects (Exp, Name_Req);
1051 New_Exp := New_Copy_Tree (Exp);
1052 Remove_Checks (Exp);
1053 return New_Exp;
1054 end Duplicate_Subexpr_Move_Checks;
1055
70482933
RK		 1056 --------------------
1057 -- Ensure_Defined --
1058 --------------------
1059
1060 procedure Ensure_Defined (Typ : Entity_Id; N : Node_Id) is
1061 IR : Node_Id;
70482933
RK		 1062
1063 begin
86cde7b1
RD		 1064 -- An itype reference must only be created if this is a local
1065 -- itype, so that gigi can elaborate it on the proper objstack.
1066
1067 if Is_Itype (Typ)
19590d70 1068 and then Scope (Typ) = Current_Scope
86cde7b1 1069 then
70482933
RK		 1070 IR := Make_Itype_Reference (Sloc (N));
1071 Set_Itype (IR, Typ);
86cde7b1 1072 Insert_Action (N, IR);
70482933
RK		 1073 end if;
1074 end Ensure_Defined;
1075
1076 ---------------------
1077 -- Evolve_And_Then --
1078 ---------------------
1079
1080 procedure Evolve_And_Then (Cond : in out Node_Id; Cond1 : Node_Id) is
1081 begin
1082 if No (Cond) then
1083 Cond := Cond1;
1084 else
1085 Cond :=
1086 Make_And_Then (Sloc (Cond1),
1087 Left_Opnd => Cond,
1088 Right_Opnd => Cond1);
1089 end if;
1090 end Evolve_And_Then;
1091
1092 --------------------
1093 -- Evolve_Or_Else --
1094 --------------------
1095
1096 procedure Evolve_Or_Else (Cond : in out Node_Id; Cond1 : Node_Id) is
1097 begin
1098 if No (Cond) then
1099 Cond := Cond1;
1100 else
1101 Cond :=
1102 Make_Or_Else (Sloc (Cond1),
1103 Left_Opnd => Cond,
1104 Right_Opnd => Cond1);
1105 end if;
1106 end Evolve_Or_Else;
1107
1108 ------------------------------
1109 -- Expand_Subtype_From_Expr --
1110 ------------------------------
1111
1112 -- This function is applicable for both static and dynamic allocation of
1113 -- objects which are constrained by an initial expression. Basically it
1114 -- transforms an unconstrained subtype indication into a constrained one.
1115 -- The expression may also be transformed in certain cases in order to
05350ac6
BD		 1116 -- avoid multiple evaluation. In the static allocation case, the general
1117 -- scheme is:
70482933
RK		 1118
1119 -- Val : T := Expr;
1120
1121 -- is transformed into
1122
1123 -- Val : Constrained_Subtype_of_T := Maybe_Modified_Expr;
1124 --
1125 -- Here are the main cases :
1126 --
1127 -- <if Expr is a Slice>
1128 -- Val : T ([Index_Subtype (Expr)]) := Expr;
1129 --
1130 -- <elsif Expr is a String Literal>
1131 -- Val : T (T'First .. T'First + Length (string literal) - 1) := Expr;
1132 --
1133 -- <elsif Expr is Constrained>
1134 -- subtype T is Type_Of_Expr
1135 -- Val : T := Expr;
1136 --
1137 -- <elsif Expr is an entity_name>
638e383e 1138 -- Val : T (constraints taken from Expr) := Expr;
70482933
RK		 1139 --
1140 -- <else>
1141 -- type Axxx is access all T;
1142 -- Rval : Axxx := Expr'ref;
638e383e 1143 -- Val : T (constraints taken from Rval) := Rval.all;
70482933
RK		 1144
1145 -- ??? note: when the Expression is allocated in the secondary stack
1146 -- we could use it directly instead of copying it by declaring
1147 -- Val : T (...) renames Rval.all
1148
1149 procedure Expand_Subtype_From_Expr
1150 (N : Node_Id;
1151 Unc_Type : Entity_Id;
1152 Subtype_Indic : Node_Id;
1153 Exp : Node_Id)
1154 is
1155 Loc : constant Source_Ptr := Sloc (N);
1156 Exp_Typ : constant Entity_Id := Etype (Exp);
1157 T : Entity_Id;
1158
1159 begin
1160 -- In general we cannot build the subtype if expansion is disabled,
1161 -- because internal entities may not have been defined. However, to
1162 -- avoid some cascaded errors, we try to continue when the expression
1163 -- is an array (or string), because it is safe to compute the bounds.
1164 -- It is in fact required to do so even in a generic context, because
1165 -- there may be constants that depend on bounds of string literal.
1166
1167 if not Expander_Active
1168 and then (No (Etype (Exp))
1169 or else Base_Type (Etype (Exp)) /= Standard_String)
1170 then
1171 return;
1172 end if;
1173
1174 if Nkind (Exp) = N_Slice then
1175 declare
1176 Slice_Type : constant Entity_Id := Etype (First_Index (Exp_Typ));
1177
1178 begin
1179 Rewrite (Subtype_Indic,
1180 Make_Subtype_Indication (Loc,
1181 Subtype_Mark => New_Reference_To (Unc_Type, Loc),
1182 Constraint =>
1183 Make_Index_Or_Discriminant_Constraint (Loc,
1184 Constraints => New_List
1185 (New_Reference_To (Slice_Type, Loc)))));
1186
1187 -- This subtype indication may be used later for contraint checks
1188 -- we better make sure that if a variable was used as a bound of
1189 -- of the original slice, its value is frozen.
1190
1191 Force_Evaluation (Low_Bound (Scalar_Range (Slice_Type)));
1192 Force_Evaluation (High_Bound (Scalar_Range (Slice_Type)));
1193 end;
1194
1195 elsif Ekind (Exp_Typ) = E_String_Literal_Subtype then
1196 Rewrite (Subtype_Indic,
1197 Make_Subtype_Indication (Loc,
1198 Subtype_Mark => New_Reference_To (Unc_Type, Loc),
1199 Constraint =>
1200 Make_Index_Or_Discriminant_Constraint (Loc,
1201 Constraints => New_List (
1202 Make_Literal_Range (Loc,
f91b40db 1203 Literal_Typ => Exp_Typ)))));
70482933
RK		 1204
1205 elsif Is_Constrained (Exp_Typ)
1206 and then not Is_Class_Wide_Type (Unc_Type)
1207 then
1208 if Is_Itype (Exp_Typ) then
1209
758c442c
GD		 1210 -- Within an initialization procedure, a selected component
1211 -- denotes a component of the enclosing record, and it appears
1212 -- as an actual in a call to its own initialization procedure.
1213 -- If this component depends on the outer discriminant, we must
1214 -- generate the proper actual subtype for it.
70482933 1215
758c442c
GD		 1216 if Nkind (Exp) = N_Selected_Component
1217 and then Within_Init_Proc
1218 then
1219 declare
1220 Decl : constant Node_Id :=
1221 Build_Actual_Subtype_Of_Component (Exp_Typ, Exp);
1222 begin
1223 if Present (Decl) then
1224 Insert_Action (N, Decl);
1225 T := Defining_Identifier (Decl);
1226 else
1227 T := Exp_Typ;
1228 end if;
1229 end;
1230
1231 -- No need to generate a new one (new what???)
1232
1233 else
1234 T := Exp_Typ;
1235 end if;
70482933
RK		 1236
1237 else
1238 T :=
1239 Make_Defining_Identifier (Loc,
1240 Chars => New_Internal_Name ('T'));
1241
1242 Insert_Action (N,
1243 Make_Subtype_Declaration (Loc,
1244 Defining_Identifier => T,
1245 Subtype_Indication => New_Reference_To (Exp_Typ, Loc)));
1246
1247 -- This type is marked as an itype even though it has an
1248 -- explicit declaration because otherwise it can be marked
1249 -- with Is_Generic_Actual_Type and generate spurious errors.
1250 -- (see sem_ch8.Analyze_Package_Renaming and sem_type.covers)
1251
1252 Set_Is_Itype (T);
1253 Set_Associated_Node_For_Itype (T, Exp);
1254 end if;
1255
1256 Rewrite (Subtype_Indic, New_Reference_To (T, Loc));
1257
1258 -- nothing needs to be done for private types with unknown discriminants
1259 -- if the underlying type is not an unconstrained composite type.
1260
1261 elsif Is_Private_Type (Unc_Type)
1262 and then Has_Unknown_Discriminants (Unc_Type)
1263 and then (not Is_Composite_Type (Underlying_Type (Unc_Type))
1264 or else Is_Constrained (Underlying_Type (Unc_Type)))
1265 then
1266 null;
1267
f4d379b8
HK		 1268 -- Nothing to be done for derived types with unknown discriminants if
1269 -- the parent type also has unknown discriminants.
1270
1271 elsif Is_Record_Type (Unc_Type)
1272 and then not Is_Class_Wide_Type (Unc_Type)
1273 and then Has_Unknown_Discriminants (Unc_Type)
1274 and then Has_Unknown_Discriminants (Underlying_Type (Unc_Type))
1275 then
1276 null;
1277
0712790c
ES		 1278 -- In Ada95, Nothing to be done if the type of the expression is
1279 -- limited, because in this case the expression cannot be copied,
1280 -- and its use can only be by reference.
10b93b2e 1281
0712790c
ES		 1282 -- In Ada2005, the context can be an object declaration whose expression
1283 -- is a function that returns in place. If the nominal subtype has
1284 -- unknown discriminants, the call still provides constraints on the
1285 -- object, and we have to create an actual subtype from it.
1286
1287 -- If the type is class-wide, the expression is dynamically tagged and
1288 -- we do not create an actual subtype either. Ditto for an interface.
1289
1290 elsif Is_Limited_Type (Exp_Typ)
1291 and then
1292 (Is_Class_Wide_Type (Exp_Typ)
1293 or else Is_Interface (Exp_Typ)
1294 or else not Has_Unknown_Discriminants (Exp_Typ)
1295 or else not Is_Composite_Type (Unc_Type))
1296 then
1297 null;
1298
1299 -- For limited interfaces, nothing to be done
1300
1301 -- This branch may be redundant once the limited interface issue is
1302 -- sorted out???
1303
1304 elsif Is_Interface (Exp_Typ)
1305 and then Is_Limited_Interface (Exp_Typ)
1306 then
10b93b2e
HK		 1307 null;
1308
86cde7b1
RD		 1309 -- For limited objects initialized with build in place function calls,
1310 -- nothing to be done; otherwise we prematurely introduce an N_Reference
1311 -- node in the expression initializing the object, which breaks the
1312 -- circuitry that detects and adds the additional arguments to the
1313 -- called function.
1314
1315 elsif Is_Build_In_Place_Function_Call (Exp) then
1316 null;
1317
70482933
RK		 1318 else
1319 Remove_Side_Effects (Exp);
1320 Rewrite (Subtype_Indic,
1321 Make_Subtype_From_Expr (Exp, Unc_Type));
1322 end if;
1323 end Expand_Subtype_From_Expr;
1324
758c442c 1325 ------------------------
f4d379b8 1326 -- Find_Interface_ADT --
758c442c
GD		 1327 ------------------------
1328
3ca505dc
JM		 1329 function Find_Interface_ADT
1330 (T : Entity_Id;
1331 Iface : Entity_Id) return Entity_Id
1332 is
1333 ADT : Elmt_Id;
ea985d95 1334 Found : Boolean := False;
3ca505dc
JM		 1335 Typ : Entity_Id := T;
1336
1337 procedure Find_Secondary_Table (Typ : Entity_Id);
f4d379b8 1338 -- Internal subprogram used to recursively climb to the ancestors
3ca505dc
JM		 1339
1340 --------------------------
1341 -- Find_Secondary_Table --
1342 --------------------------
1343
1344 procedure Find_Secondary_Table (Typ : Entity_Id) is
1345 AI_Elmt : Elmt_Id;
1346 AI : Node_Id;
1347
1348 begin
dee4682a
JM		 1349 pragma Assert (Typ /= Iface);
1350
1351 -- Climb to the ancestor (if any) handling synchronized interface
1352 -- derivations and private types
1353
1354 if Is_Concurrent_Record_Type (Typ) then
1355 declare
1356 Iface_List : constant List_Id := Abstract_Interface_List (Typ);
1357
1358 begin
1359 if Is_Non_Empty_List (Iface_List) then
1360 Find_Secondary_Table (Etype (First (Iface_List)));
1361 end if;
1362 end;
f4d379b8 1363
dee4682a 1364 elsif Present (Full_View (Etype (Typ))) then
f4d379b8
HK		 1365 if Full_View (Etype (Typ)) /= Typ then
1366 Find_Secondary_Table (Full_View (Etype (Typ)));
1367 end if;
1368
1369 elsif Etype (Typ) /= Typ then
3ca505dc
JM		 1370 Find_Secondary_Table (Etype (Typ));
1371 end if;
1372
dee4682a 1373 -- Traverse the list of interfaces implemented by the type
f4d379b8 1374
dee4682a
JM		 1375 if not Found
1376 and then Present (Abstract_Interfaces (Typ))
3ca505dc
JM		 1377 and then not Is_Empty_Elmt_List (Abstract_Interfaces (Typ))
1378 then
1379 AI_Elmt := First_Elmt (Abstract_Interfaces (Typ));
1380 while Present (AI_Elmt) loop
1381 AI := Node (AI_Elmt);
1382
1383 if AI = Iface or else Is_Ancestor (Iface, AI) then
1384 Found := True;
1385 return;
1386 end if;
1387
1388 Next_Elmt (ADT);
1389 Next_Elmt (AI_Elmt);
1390 end loop;
1391 end if;
1392 end Find_Secondary_Table;
1393
dee4682a 1394 -- Start of processing for Find_Interface_ADT
3ca505dc
JM		 1395
1396 begin
dee4682a
JM		 1397 pragma Assert (Is_Interface (Iface));
1398
3ca505dc
JM		 1399 -- Handle private types
1400
1401 if Has_Private_Declaration (Typ)
1402 and then Present (Full_View (Typ))
1403 then
1404 Typ := Full_View (Typ);
1405 end if;
1406
1407 -- Handle access types
1408
1409 if Is_Access_Type (Typ) then
1410 Typ := Directly_Designated_Type (Typ);
1411 end if;
1412
1413 -- Handle task and protected types implementing interfaces
1414
dee4682a 1415 if Is_Concurrent_Type (Typ) then
3ca505dc
JM		 1416 Typ := Corresponding_Record_Type (Typ);
1417 end if;
1418
dee4682a
JM		 1419 pragma Assert
1420 (not Is_Class_Wide_Type (Typ)
1421 and then Ekind (Typ) /= E_Incomplete_Type);
1422
3ca505dc
JM		 1423 ADT := Next_Elmt (First_Elmt (Access_Disp_Table (Typ)));
1424 pragma Assert (Present (Node (ADT)));
1425 Find_Secondary_Table (Typ);
1426 pragma Assert (Found);
1427 return Node (ADT);
1428 end Find_Interface_ADT;
1429
1430 ------------------------
1431 -- Find_Interface_Tag --
1432 ------------------------
1433
1434 function Find_Interface_Tag
dee4682a
JM		 1435 (T : Entity_Id;
1436 Iface : Entity_Id) return Entity_Id
758c442c 1437 is
3ca505dc 1438 AI_Tag : Entity_Id;
dee4682a 1439 Found : Boolean := False;
3ca505dc 1440 Typ : Entity_Id := T;
758c442c 1441
dee4682a
JM		 1442 Is_Primary_Tag : Boolean := False;
1443
1444 Is_Sync_Typ : Boolean := False;
1445 -- In case of non concurrent-record-types each parent-type has the
1446 -- tags associated with the interface types that are not implemented
1447 -- by the ancestors; concurrent-record-types have their whole list of
1448 -- interface tags (and this case requires some special management).
1449
59e54267 1450 procedure Find_Tag (Typ : Entity_Id);
3ca505dc 1451 -- Internal subprogram used to recursively climb to the ancestors
758c442c 1452
ea985d95
RD		 1453 --------------
1454 -- Find_Tag --
1455 --------------
758c442c 1456
59e54267 1457 procedure Find_Tag (Typ : Entity_Id) is
758c442c
GD		 1458 AI_Elmt : Elmt_Id;
1459 AI : Node_Id;
1460
1461 begin
1462 -- Check if the interface is an immediate ancestor of the type and
1463 -- therefore shares the main tag.
1464
1465 if Typ = Iface then
dee4682a
JM		 1466 if Is_Sync_Typ then
1467 Is_Primary_Tag := True;
1468 else
1469 pragma Assert
1470 (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag));
1471 AI_Tag := First_Tag_Component (Typ);
1472 end if;
1473
3ca505dc 1474 Found := True;
758c442c
GD		 1475 return;
1476 end if;
1477
dee4682a
JM		 1478 -- Handle synchronized interface derivations
1479
1480 if Is_Concurrent_Record_Type (Typ) then
1481 declare
1482 Iface_List : constant List_Id := Abstract_Interface_List (Typ);
1483 begin
1484 if Is_Non_Empty_List (Iface_List) then
1485 Find_Tag (Etype (First (Iface_List)));
1486 end if;
1487 end;
1488
f4d379b8
HK		 1489 -- Climb to the root type handling private types
1490
dee4682a 1491 elsif Present (Full_View (Etype (Typ))) then
f4d379b8
HK		 1492 if Full_View (Etype (Typ)) /= Typ then
1493 Find_Tag (Full_View (Etype (Typ)));
1494 end if;
758c442c 1495
f4d379b8 1496 elsif Etype (Typ) /= Typ then
3ca505dc 1497 Find_Tag (Etype (Typ));
758c442c
GD		 1498 end if;
1499
1500 -- Traverse the list of interfaces implemented by the type
1501
1502 if not Found
3ca505dc
JM		 1503 and then Present (Abstract_Interfaces (Typ))
1504 and then not (Is_Empty_Elmt_List (Abstract_Interfaces (Typ)))
758c442c 1505 then
10b93b2e 1506 -- Skip the tag associated with the primary table
758c442c 1507
dee4682a
JM		 1508 if not Is_Sync_Typ then
1509 pragma Assert
1510 (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag));
1511 AI_Tag := Next_Tag_Component (First_Tag_Component (Typ));
1512 pragma Assert (Present (AI_Tag));
1513 end if;
758c442c 1514
3ca505dc 1515 AI_Elmt := First_Elmt (Abstract_Interfaces (Typ));
758c442c
GD		 1516 while Present (AI_Elmt) loop
1517 AI := Node (AI_Elmt);
1518
1519 if AI = Iface or else Is_Ancestor (Iface, AI) then
1520 Found := True;
1521 return;
1522 end if;
1523
1524 AI_Tag := Next_Tag_Component (AI_Tag);
1525 Next_Elmt (AI_Elmt);
758c442c
GD		 1526 end loop;
1527 end if;
3ca505dc
JM		 1528 end Find_Tag;
1529
1530 -- Start of processing for Find_Interface_Tag
758c442c
GD		 1531
1532 begin
f4d379b8
HK		 1533 pragma Assert (Is_Interface (Iface));
1534
3ca505dc 1535 -- Handle private types
758c442c 1536
3ca505dc
JM		 1537 if Has_Private_Declaration (Typ)
1538 and then Present (Full_View (Typ))
1539 then
1540 Typ := Full_View (Typ);
1541 end if;
758c442c 1542
3ca505dc 1543 -- Handle access types
758c442c 1544
3ca505dc
JM		 1545 if Is_Access_Type (Typ) then
1546 Typ := Directly_Designated_Type (Typ);
1547 end if;
758c442c 1548
3ca505dc 1549 -- Handle task and protected types implementing interfaces
758c442c 1550
10b93b2e 1551 if Is_Concurrent_Type (Typ) then
3ca505dc
JM		 1552 Typ := Corresponding_Record_Type (Typ);
1553 end if;
1554
10b93b2e
HK		 1555 if Is_Class_Wide_Type (Typ) then
1556 Typ := Etype (Typ);
1557 end if;
1558
1559 -- Handle entities from the limited view
1560
1561 if Ekind (Typ) = E_Incomplete_Type then
1562 pragma Assert (Present (Non_Limited_View (Typ)));
1563 Typ := Non_Limited_View (Typ);
1564 end if;
1565
dee4682a
JM		 1566 if not Is_Concurrent_Record_Type (Typ) then
1567 Find_Tag (Typ);
1568 pragma Assert (Found);
1569 return AI_Tag;
1570
1571 -- Concurrent record types
1572
1573 else
1574 Is_Sync_Typ := True;
1575 AI_Tag := Next_Tag_Component (First_Tag_Component (Typ));
1576 Find_Tag (Typ);
1577 pragma Assert (Found);
1578
1579 if Is_Primary_Tag then
1580 return First_Tag_Component (Typ);
1581 else
1582 return AI_Tag;
1583 end if;
1584 end if;
758c442c
GD		 1585 end Find_Interface_Tag;
1586
ea985d95
RD		 1587 --------------------
1588 -- Find_Interface --
1589 --------------------
1590
1591 function Find_Interface
1592 (T : Entity_Id;
1593 Comp : Entity_Id) return Entity_Id
1594 is
1595 AI_Tag : Entity_Id;
1596 Found : Boolean := False;
1597 Iface : Entity_Id;
1598 Typ : Entity_Id := T;
1599
dee4682a
JM		 1600 Is_Sync_Typ : Boolean := False;
1601 -- In case of non concurrent-record-types each parent-type has the
1602 -- tags associated with the interface types that are not implemented
1603 -- by the ancestors; concurrent-record-types have their whole list of
1604 -- interface tags (and this case requires some special management).
1605
59e54267 1606 procedure Find_Iface (Typ : Entity_Id);
ea985d95
RD		 1607 -- Internal subprogram used to recursively climb to the ancestors
1608
1609 ----------------
1610 -- Find_Iface --
1611 ----------------
1612
59e54267 1613 procedure Find_Iface (Typ : Entity_Id) is
ea985d95
RD		 1614 AI_Elmt : Elmt_Id;
1615
1616 begin
1617 -- Climb to the root type
1618
dee4682a
JM		 1619 -- Handle sychronized interface derivations
1620
1621 if Is_Concurrent_Record_Type (Typ) then
1622 declare
1623 Iface_List : constant List_Id := Abstract_Interface_List (Typ);
1624 begin
1625 if Is_Non_Empty_List (Iface_List) then
1626 Find_Iface (Etype (First (Iface_List)));
1627 end if;
1628 end;
1629
1630 -- Handle the common case
1631
1632 elsif Etype (Typ) /= Typ then
1633 pragma Assert (not Present (Full_View (Etype (Typ))));
ea985d95
RD		 1634 Find_Iface (Etype (Typ));
1635 end if;
1636
1637 -- Traverse the list of interfaces implemented by the type
1638
1639 if not Found
1640 and then Present (Abstract_Interfaces (Typ))
1641 and then not (Is_Empty_Elmt_List (Abstract_Interfaces (Typ)))
1642 then
1643 -- Skip the tag associated with the primary table
1644
dee4682a
JM		 1645 if not Is_Sync_Typ then
1646 pragma Assert
1647 (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag));
1648 AI_Tag := Next_Tag_Component (First_Tag_Component (Typ));
1649 pragma Assert (Present (AI_Tag));
1650 end if;
ea985d95
RD		 1651
1652 AI_Elmt := First_Elmt (Abstract_Interfaces (Typ));
1653 while Present (AI_Elmt) loop
1654 if AI_Tag = Comp then
1655 Iface := Node (AI_Elmt);
1656 Found := True;
1657 return;
1658 end if;
1659
1660 AI_Tag := Next_Tag_Component (AI_Tag);
1661 Next_Elmt (AI_Elmt);
1662 end loop;
1663 end if;
1664 end Find_Iface;
1665
1666 -- Start of processing for Find_Interface
1667
1668 begin
1669 -- Handle private types
1670
1671 if Has_Private_Declaration (Typ)
1672 and then Present (Full_View (Typ))
1673 then
1674 Typ := Full_View (Typ);
1675 end if;
1676
1677 -- Handle access types
1678
1679 if Is_Access_Type (Typ) then
1680 Typ := Directly_Designated_Type (Typ);
1681 end if;
1682
1683 -- Handle task and protected types implementing interfaces
1684
1685 if Is_Concurrent_Type (Typ) then
1686 Typ := Corresponding_Record_Type (Typ);
1687 end if;
1688
1689 if Is_Class_Wide_Type (Typ) then
1690 Typ := Etype (Typ);
1691 end if;
1692
1693 -- Handle entities from the limited view
1694
1695 if Ekind (Typ) = E_Incomplete_Type then
1696 pragma Assert (Present (Non_Limited_View (Typ)));
1697 Typ := Non_Limited_View (Typ);
1698 end if;
1699
dee4682a
JM		 1700 if Is_Concurrent_Record_Type (Typ) then
1701 Is_Sync_Typ := True;
1702 AI_Tag := Next_Tag_Component (First_Tag_Component (Typ));
1703 end if;
1704
ea985d95
RD		 1705 Find_Iface (Typ);
1706 pragma Assert (Found);
1707 return Iface;
1708 end Find_Interface;
1709
70482933
RK		 1710 ------------------
1711 -- Find_Prim_Op --
1712 ------------------
1713
1714 function Find_Prim_Op (T : Entity_Id; Name : Name_Id) return Entity_Id is
1715 Prim : Elmt_Id;
1716 Typ : Entity_Id := T;
59e54267 1717 Op : Entity_Id;
70482933
RK		 1718
1719 begin
1720 if Is_Class_Wide_Type (Typ) then
1721 Typ := Root_Type (Typ);
1722 end if;
1723
1724 Typ := Underlying_Type (Typ);
1725
59e54267
ES		 1726 -- Loop through primitive operations
1727
70482933 1728 Prim := First_Elmt (Primitive_Operations (Typ));
59e54267
ES		 1729 while Present (Prim) loop
1730 Op := Node (Prim);
1731
1732 -- We can retrieve primitive operations by name if it is an internal
1733 -- name. For equality we must check that both of its operands have
1734 -- the same type, to avoid confusion with user-defined equalities
1735 -- than may have a non-symmetric signature.
1736
1737 exit when Chars (Op) = Name
1738 and then
1739 (Name /= Name_Op_Eq
1740 or else Etype (First_Entity (Op)) = Etype (Last_Entity (Op)));
1741
70482933
RK		 1742 Next_Elmt (Prim);
1743 pragma Assert (Present (Prim));
1744 end loop;
1745
1746 return Node (Prim);
1747 end Find_Prim_Op;
1748
dee4682a
JM		 1749 ------------------
1750 -- Find_Prim_Op --
1751 ------------------
1752
fbf5a39b
AC		 1753 function Find_Prim_Op
1754 (T : Entity_Id;
1755 Name : TSS_Name_Type) return Entity_Id
1756 is
1757 Prim : Elmt_Id;
1758 Typ : Entity_Id := T;
1759
1760 begin
1761 if Is_Class_Wide_Type (Typ) then
1762 Typ := Root_Type (Typ);
1763 end if;
1764
1765 Typ := Underlying_Type (Typ);
1766
1767 Prim := First_Elmt (Primitive_Operations (Typ));
1768 while not Is_TSS (Node (Prim), Name) loop
1769 Next_Elmt (Prim);
1770 pragma Assert (Present (Prim));
1771 end loop;
1772
1773 return Node (Prim);
1774 end Find_Prim_Op;
1775
70482933
RK		 1776 ----------------------
1777 -- Force_Evaluation --
1778 ----------------------
1779
1780 procedure Force_Evaluation (Exp : Node_Id; Name_Req : Boolean := False) is
1781 begin
d9e0a587 1782 Remove_Side_Effects (Exp, Name_Req, Variable_Ref => True);
70482933
RK		 1783 end Force_Evaluation;
1784
1785 ------------------------
1786 -- Generate_Poll_Call --
1787 ------------------------
1788
1789 procedure Generate_Poll_Call (N : Node_Id) is
1790 begin
1791 -- No poll call if polling not active
1792
1793 if not Polling_Required then
1794 return;
1795
1796 -- Otherwise generate require poll call
1797
1798 else
1799 Insert_Before_And_Analyze (N,
1800 Make_Procedure_Call_Statement (Sloc (N),
1801 Name => New_Occurrence_Of (RTE (RE_Poll), Sloc (N))));
1802 end if;
1803 end Generate_Poll_Call;
1804
fbf5a39b
AC		 1805 ---------------------------------
1806 -- Get_Current_Value_Condition --
1807 ---------------------------------
1808
05350ac6
BD		 1809 -- Note: the implementation of this procedure is very closely tied to the
1810 -- implementation of Set_Current_Value_Condition. In the Get procedure, we
1811 -- interpret Current_Value fields set by the Set procedure, so the two
1812 -- procedures need to be closely coordinated.
1813
fbf5a39b
AC		 1814 procedure Get_Current_Value_Condition
1815 (Var : Node_Id;
1816 Op : out Node_Kind;
1817 Val : out Node_Id)
1818 is
59e54267
ES		 1819 Loc : constant Source_Ptr := Sloc (Var);
1820 Ent : constant Entity_Id := Entity (Var);
fbf5a39b 1821
05350ac6
BD		 1822 procedure Process_Current_Value_Condition
1823 (N : Node_Id;
1824 S : Boolean);
1825 -- N is an expression which holds either True (S = True) or False (S =
1826 -- False) in the condition. This procedure digs out the expression and
1827 -- if it refers to Ent, sets Op and Val appropriately.
1828
1829 -------------------------------------
1830 -- Process_Current_Value_Condition --
1831 -------------------------------------
1832
1833 procedure Process_Current_Value_Condition
1834 (N : Node_Id;
1835 S : Boolean)
1836 is
1837 Cond : Node_Id;
1838 Sens : Boolean;
1839
1840 begin
1841 Cond := N;
1842 Sens := S;
1843
1844 -- Deal with NOT operators, inverting sense
1845
1846 while Nkind (Cond) = N_Op_Not loop
1847 Cond := Right_Opnd (Cond);
1848 Sens := not Sens;
1849 end loop;
1850
1851 -- Deal with AND THEN and AND cases
1852
1853 if Nkind (Cond) = N_And_Then
1854 or else Nkind (Cond) = N_Op_And
1855 then
1856 -- Don't ever try to invert a condition that is of the form
1857 -- of an AND or AND THEN (since we are not doing sufficiently
1858 -- general processing to allow this).
1859
1860 if Sens = False then
1861 Op := N_Empty;
1862 Val := Empty;
1863 return;
1864 end if;
1865
1866 -- Recursively process AND and AND THEN branches
1867
1868 Process_Current_Value_Condition (Left_Opnd (Cond), True);
1869
1870 if Op /= N_Empty then
1871 return;
1872 end if;
1873
1874 Process_Current_Value_Condition (Right_Opnd (Cond), True);
1875 return;
1876
1877 -- Case of relational operator
1878
1879 elsif Nkind (Cond) in N_Op_Compare then
1880 Op := Nkind (Cond);
1881
1882 -- Invert sense of test if inverted test
1883
1884 if Sens = False then
1885 case Op is
1886 when N_Op_Eq => Op := N_Op_Ne;
1887 when N_Op_Ne => Op := N_Op_Eq;
1888 when N_Op_Lt => Op := N_Op_Ge;
1889 when N_Op_Gt => Op := N_Op_Le;
1890 when N_Op_Le => Op := N_Op_Gt;
1891 when N_Op_Ge => Op := N_Op_Lt;
1892 when others => raise Program_Error;
1893 end case;
1894 end if;
1895
1896 -- Case of entity op value
1897
1898 if Is_Entity_Name (Left_Opnd (Cond))
1899 and then Ent = Entity (Left_Opnd (Cond))
1900 and then Compile_Time_Known_Value (Right_Opnd (Cond))
1901 then
1902 Val := Right_Opnd (Cond);
1903
1904 -- Case of value op entity
1905
1906 elsif Is_Entity_Name (Right_Opnd (Cond))
1907 and then Ent = Entity (Right_Opnd (Cond))
1908 and then Compile_Time_Known_Value (Left_Opnd (Cond))
1909 then
1910 Val := Left_Opnd (Cond);
1911
1912 -- We are effectively swapping operands
1913
1914 case Op is
1915 when N_Op_Eq => null;
1916 when N_Op_Ne => null;
1917 when N_Op_Lt => Op := N_Op_Gt;
1918 when N_Op_Gt => Op := N_Op_Lt;
1919 when N_Op_Le => Op := N_Op_Ge;
1920 when N_Op_Ge => Op := N_Op_Le;
1921 when others => raise Program_Error;
1922 end case;
1923
1924 else
1925 Op := N_Empty;
1926 end if;
1927
1928 return;
1929
1930 -- Case of Boolean variable reference, return as though the
1931 -- reference had said var = True.
1932
1933 else
1934 if Is_Entity_Name (Cond)
1935 and then Ent = Entity (Cond)
1936 then
1937 Val := New_Occurrence_Of (Standard_True, Sloc (Cond));
1938
1939 if Sens = False then
1940 Op := N_Op_Ne;
1941 else
1942 Op := N_Op_Eq;
1943 end if;
1944 end if;
1945 end if;
1946 end Process_Current_Value_Condition;
1947
1948 -- Start of processing for Get_Current_Value_Condition
1949
fbf5a39b
AC		 1950 begin
1951 Op := N_Empty;
1952 Val := Empty;
1953
59e54267 1954 -- Immediate return, nothing doing, if this is not an object
fbf5a39b 1955
59e54267
ES		 1956 if Ekind (Ent) not in Object_Kind then
1957 return;
1958 end if;
fbf5a39b 1959
59e54267 1960 -- Otherwise examine current value
fbf5a39b 1961
59e54267
ES		 1962 declare
1963 CV : constant Node_Id := Current_Value (Ent);
1964 Sens : Boolean;
1965 Stm : Node_Id;
fbf5a39b 1966
59e54267
ES		 1967 begin
1968 -- If statement. Condition is known true in THEN section, known False
1969 -- in any ELSIF or ELSE part, and unknown outside the IF statement.
fbf5a39b 1970
59e54267 1971 if Nkind (CV) = N_If_Statement then
fbf5a39b 1972
59e54267 1973 -- Before start of IF statement
fbf5a39b 1974
59e54267
ES		 1975 if Loc < Sloc (CV) then
1976 return;
fbf5a39b 1977
59e54267 1978 -- After end of IF statement
fbf5a39b 1979
59e54267
ES		 1980 elsif Loc >= Sloc (CV) + Text_Ptr (UI_To_Int (End_Span (CV))) then
1981 return;
1982 end if;
fbf5a39b 1983
59e54267
ES		 1984 -- At this stage we know that we are within the IF statement, but
1985 -- unfortunately, the tree does not record the SLOC of the ELSE so
1986 -- we cannot use a simple SLOC comparison to distinguish between
1987 -- the then/else statements, so we have to climb the tree.
fbf5a39b 1988
59e54267
ES		 1989 declare
1990 N : Node_Id;
fbf5a39b 1991
59e54267
ES		 1992 begin
1993 N := Parent (Var);
1994 while Parent (N) /= CV loop
1995 N := Parent (N);
fbf5a39b 1996
59e54267
ES		 1997 -- If we fall off the top of the tree, then that's odd, but
1998 -- perhaps it could occur in some error situation, and the
1999 -- safest response is simply to assume that the outcome of
2000 -- the condition is unknown. No point in bombing during an
2001 -- attempt to optimize things.
fbf5a39b 2002
59e54267
ES		 2003 if No (N) then
2004 return;
2005 end if;
2006 end loop;
fbf5a39b 2007
59e54267
ES		 2008 -- Now we have N pointing to a node whose parent is the IF
2009 -- statement in question, so now we can tell if we are within
2010 -- the THEN statements.
fbf5a39b 2011
59e54267
ES		 2012 if Is_List_Member (N)
2013 and then List_Containing (N) = Then_Statements (CV)
2014 then
2015 Sens := True;
fbf5a39b 2016
05350ac6
BD		 2017 -- If the variable reference does not come from source, we
2018 -- cannot reliably tell whether it appears in the else part.
2019 -- In particular, if if appears in generated code for a node
2020 -- that requires finalization, it may be attached to a list
2021 -- that has not been yet inserted into the code. For now,
2022 -- treat it as unknown.
2023
2024 elsif not Comes_From_Source (N) then
2025 return;
2026
2027 -- Otherwise we must be in ELSIF or ELSE part
fbf5a39b 2028
59e54267
ES		 2029 else
2030 Sens := False;
2031 end if;
2032 end;
fbf5a39b 2033
59e54267
ES		 2034 -- ELSIF part. Condition is known true within the referenced
2035 -- ELSIF, known False in any subsequent ELSIF or ELSE part, and
2036 -- unknown before the ELSE part or after the IF statement.
fbf5a39b 2037
59e54267
ES		 2038 elsif Nkind (CV) = N_Elsif_Part then
2039 Stm := Parent (CV);
fbf5a39b 2040
59e54267 2041 -- Before start of ELSIF part
fbf5a39b 2042
59e54267
ES		 2043 if Loc < Sloc (CV) then
2044 return;
fbf5a39b 2045
59e54267 2046 -- After end of IF statement
fbf5a39b 2047
59e54267
ES		 2048 elsif Loc >= Sloc (Stm) +
2049 Text_Ptr (UI_To_Int (End_Span (Stm)))
2050 then
2051 return;
2052 end if;
fbf5a39b 2053
59e54267
ES		 2054 -- Again we lack the SLOC of the ELSE, so we need to climb the
2055 -- tree to see if we are within the ELSIF part in question.
fbf5a39b 2056
59e54267
ES		 2057 declare
2058 N : Node_Id;
fbf5a39b 2059
59e54267
ES		 2060 begin
2061 N := Parent (Var);
2062 while Parent (N) /= Stm loop
2063 N := Parent (N);
fbf5a39b 2064
59e54267
ES		 2065 -- If we fall off the top of the tree, then that's odd, but
2066 -- perhaps it could occur in some error situation, and the
2067 -- safest response is simply to assume that the outcome of
2068 -- the condition is unknown. No point in bombing during an
2069 -- attempt to optimize things.
fbf5a39b 2070
59e54267
ES		 2071 if No (N) then
2072 return;
2073 end if;
2074 end loop;
fbf5a39b 2075
59e54267
ES		 2076 -- Now we have N pointing to a node whose parent is the IF
2077 -- statement in question, so see if is the ELSIF part we want.
2078 -- the THEN statements.
fbf5a39b 2079
59e54267
ES		 2080 if N = CV then
2081 Sens := True;
fbf5a39b 2082
59e54267 2083 -- Otherwise we must be in susbequent ELSIF or ELSE part
fbf5a39b 2084
59e54267
ES		 2085 else
2086 Sens := False;
2087 end if;
2088 end;
fbf5a39b 2089
05350ac6
BD		 2090 -- Iteration scheme of while loop. The condition is known to be
2091 -- true within the body of the loop.
59e54267 2092
05350ac6
BD		 2093 elsif Nkind (CV) = N_Iteration_Scheme then
2094 declare
2095 Loop_Stmt : constant Node_Id := Parent (CV);
fbf5a39b 2096
05350ac6
BD		 2097 begin
2098 -- Before start of body of loop
fbf5a39b 2099
05350ac6
BD		 2100 if Loc < Sloc (Loop_Stmt) then
2101 return;
fbf5a39b 2102
05350ac6 2103 -- After end of LOOP statement
59e54267 2104
05350ac6
BD		 2105 elsif Loc >= Sloc (End_Label (Loop_Stmt)) then
2106 return;
59e54267 2107
05350ac6 2108 -- We are within the body of the loop
59e54267 2109
05350ac6
BD		 2110 else
2111 Sens := True;
2112 end if;
2113 end;
fbf5a39b 2114
05350ac6 2115 -- All other cases of Current_Value settings
fbf5a39b 2116
05350ac6
BD		 2117 else
2118 return;
59e54267 2119 end if;
05350ac6
BD		 2120
2121 -- If we fall through here, then we have a reportable condition, Sens
2122 -- is True if the condition is true and False if it needs inverting.
2123
2124 Process_Current_Value_Condition (Condition (CV), Sens);
59e54267 2125 end;
fbf5a39b
AC		 2126 end Get_Current_Value_Condition;
2127
0712790c
ES		 2128 ---------------------------------
2129 -- Has_Controlled_Coextensions --
2130 ---------------------------------
2131
2132 function Has_Controlled_Coextensions (Typ : Entity_Id) return Boolean is
2133 D_Typ : Entity_Id;
2134 Discr : Entity_Id;
2135
2136 begin
2137 -- Only consider record types
2138
2139 if Ekind (Typ) /= E_Record_Type
2140 and then Ekind (Typ) /= E_Record_Subtype
2141 then
2142 return False;
2143 end if;
2144
2145 if Has_Discriminants (Typ) then
2146 Discr := First_Discriminant (Typ);
2147 while Present (Discr) loop
2148 D_Typ := Etype (Discr);
2149
2150 if Ekind (D_Typ) = E_Anonymous_Access_Type
2151 and then
2152 (Is_Controlled (Directly_Designated_Type (D_Typ))
2153 or else
2154 Is_Concurrent_Type (Directly_Designated_Type (D_Typ)))
2155 then
2156 return True;
2157 end if;
2158
2159 Next_Discriminant (Discr);
2160 end loop;
2161 end if;
2162
2163 return False;
2164 end Has_Controlled_Coextensions;
2165
70482933
RK		 2166 --------------------
2167 -- Homonym_Number --
2168 --------------------
2169
2170 function Homonym_Number (Subp : Entity_Id) return Nat is
2171 Count : Nat;
2172 Hom : Entity_Id;
2173
2174 begin
2175 Count := 1;
2176 Hom := Homonym (Subp);
2177 while Present (Hom) loop
2178 if Scope (Hom) = Scope (Subp) then
2179 Count := Count + 1;
2180 end if;
2181
2182 Hom := Homonym (Hom);
2183 end loop;
2184
2185 return Count;
2186 end Homonym_Number;
2187
2188 ------------------------------
2189 -- In_Unconditional_Context --
2190 ------------------------------
2191
2192 function In_Unconditional_Context (Node : Node_Id) return Boolean is
2193 P : Node_Id;
2194
2195 begin
2196 P := Node;
2197 while Present (P) loop
2198 case Nkind (P) is
2199 when N_Subprogram_Body =>
2200 return True;
2201
2202 when N_If_Statement =>
2203 return False;
2204
2205 when N_Loop_Statement =>
2206 return False;
2207
2208 when N_Case_Statement =>
2209 return False;
2210
2211 when others =>
2212 P := Parent (P);
2213 end case;
2214 end loop;
2215
2216 return False;
2217 end In_Unconditional_Context;
2218
2219 -------------------
2220 -- Insert_Action --
2221 -------------------
2222
2223 procedure Insert_Action (Assoc_Node : Node_Id; Ins_Action : Node_Id) is
2224 begin
2225 if Present (Ins_Action) then
2226 Insert_Actions (Assoc_Node, New_List (Ins_Action));
2227 end if;
2228 end Insert_Action;
2229
2230 -- Version with check(s) suppressed
2231
2232 procedure Insert_Action
2233 (Assoc_Node : Node_Id; Ins_Action : Node_Id; Suppress : Check_Id)
2234 is
2235 begin
2236 Insert_Actions (Assoc_Node, New_List (Ins_Action), Suppress);
2237 end Insert_Action;
2238
2239 --------------------
2240 -- Insert_Actions --
2241 --------------------
2242
2243 procedure Insert_Actions (Assoc_Node : Node_Id; Ins_Actions : List_Id) is
2244 N : Node_Id;
2245 P : Node_Id;
2246
2247 Wrapped_Node : Node_Id := Empty;
2248
2249 begin
2250 if No (Ins_Actions) or else Is_Empty_List (Ins_Actions) then
2251 return;
2252 end if;
2253
2254 -- Ignore insert of actions from inside default expression in the
2255 -- special preliminary analyze mode. Any insertions at this point
2256 -- have no relevance, since we are only doing the analyze to freeze
2257 -- the types of any static expressions. See section "Handling of
2258 -- Default Expressions" in the spec of package Sem for further details.
2259
2260 if In_Default_Expression then
2261 return;
2262 end if;
2263
2264 -- If the action derives from stuff inside a record, then the actions
2265 -- are attached to the current scope, to be inserted and analyzed on
2266 -- exit from the scope. The reason for this is that we may also
2267 -- be generating freeze actions at the same time, and they must
2268 -- eventually be elaborated in the correct order.
2269
2270 if Is_Record_Type (Current_Scope)
2271 and then not Is_Frozen (Current_Scope)
2272 then
2273 if No (Scope_Stack.Table
2274 (Scope_Stack.Last).Pending_Freeze_Actions)
2275 then
2276 Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions :=
2277 Ins_Actions;
2278 else
2279 Append_List
2280 (Ins_Actions,
2281 Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions);
2282 end if;
2283
2284 return;
2285 end if;
2286
2287 -- We now intend to climb up the tree to find the right point to
2288 -- insert the actions. We start at Assoc_Node, unless this node is
2289 -- a subexpression in which case we start with its parent. We do this
2290 -- for two reasons. First it speeds things up. Second, if Assoc_Node
2291 -- is itself one of the special nodes like N_And_Then, then we assume
2292 -- that an initial request to insert actions for such a node does not
2293 -- expect the actions to get deposited in the node for later handling
2294 -- when the node is expanded, since clearly the node is being dealt
2295 -- with by the caller. Note that in the subexpression case, N is
2296 -- always the child we came from.
2297
2298 -- N_Raise_xxx_Error is an annoying special case, it is a statement
2299 -- if it has type Standard_Void_Type, and a subexpression otherwise.
2300 -- otherwise. Procedure attribute references are also statements.
2301
2302 if Nkind (Assoc_Node) in N_Subexpr
2303 and then (Nkind (Assoc_Node) in N_Raise_xxx_Error
2304 or else Etype (Assoc_Node) /= Standard_Void_Type)
2305 and then (Nkind (Assoc_Node) /= N_Attribute_Reference
2306 or else
2307 not Is_Procedure_Attribute_Name
2308 (Attribute_Name (Assoc_Node)))
2309 then
fbf5a39b 2310 P := Assoc_Node; -- ??? does not agree with above!
70482933
RK		 2311 N := Parent (Assoc_Node);
2312
2313 -- Non-subexpression case. Note that N is initially Empty in this
2314 -- case (N is only guaranteed Non-Empty in the subexpr case).
2315
2316 else
2317 P := Assoc_Node;
2318 N := Empty;
2319 end if;
2320
2321 -- Capture root of the transient scope
2322
2323 if Scope_Is_Transient then
05350ac6 2324 Wrapped_Node := Node_To_Be_Wrapped;
70482933
RK		 2325 end if;
2326
2327 loop
2328 pragma Assert (Present (P));
2329
2330 case Nkind (P) is
2331
2332 -- Case of right operand of AND THEN or OR ELSE. Put the actions
2333 -- in the Actions field of the right operand. They will be moved
2334 -- out further when the AND THEN or OR ELSE operator is expanded.
2335 -- Nothing special needs to be done for the left operand since
2336 -- in that case the actions are executed unconditionally.
2337
2338 when N_And_Then | N_Or_Else =>
2339 if N = Right_Opnd (P) then
2340 if Present (Actions (P)) then
2341 Insert_List_After_And_Analyze
2342 (Last (Actions (P)), Ins_Actions);
2343 else
2344 Set_Actions (P, Ins_Actions);
2345 Analyze_List (Actions (P));
2346 end if;
2347
2348 return;
2349 end if;
2350
2351 -- Then or Else operand of conditional expression. Add actions to
2352 -- Then_Actions or Else_Actions field as appropriate. The actions
2353 -- will be moved further out when the conditional is expanded.
2354
2355 when N_Conditional_Expression =>
2356 declare
2357 ThenX : constant Node_Id := Next (First (Expressions (P)));
2358 ElseX : constant Node_Id := Next (ThenX);
2359
2360 begin
2361 -- Actions belong to the then expression, temporarily
2362 -- place them as Then_Actions of the conditional expr.
2363 -- They will be moved to the proper place later when
2364 -- the conditional expression is expanded.
2365
2366 if N = ThenX then
2367 if Present (Then_Actions (P)) then
2368 Insert_List_After_And_Analyze
2369 (Last (Then_Actions (P)), Ins_Actions);
2370 else
2371 Set_Then_Actions (P, Ins_Actions);
2372 Analyze_List (Then_Actions (P));
2373 end if;
2374
2375 return;
2376
2377 -- Actions belong to the else expression, temporarily
2378 -- place them as Else_Actions of the conditional expr.
2379 -- They will be moved to the proper place later when
2380 -- the conditional expression is expanded.
2381
2382 elsif N = ElseX then
2383 if Present (Else_Actions (P)) then
2384 Insert_List_After_And_Analyze
2385 (Last (Else_Actions (P)), Ins_Actions);
2386 else
2387 Set_Else_Actions (P, Ins_Actions);
2388 Analyze_List (Else_Actions (P));
2389 end if;
2390
2391 return;
2392
2393 -- Actions belong to the condition. In this case they are
2394 -- unconditionally executed, and so we can continue the
2395 -- search for the proper insert point.
2396
2397 else
2398 null;
2399 end if;
2400 end;
2401
2402 -- Case of appearing in the condition of a while expression or
2403 -- elsif. We insert the actions into the Condition_Actions field.
2404 -- They will be moved further out when the while loop or elsif
2405 -- is analyzed.
2406
2407 when N_Iteration_Scheme |
2408 N_Elsif_Part
2409 =>
2410 if N = Condition (P) then
2411 if Present (Condition_Actions (P)) then
2412 Insert_List_After_And_Analyze
2413 (Last (Condition_Actions (P)), Ins_Actions);
2414 else
2415 Set_Condition_Actions (P, Ins_Actions);
2416
2417 -- Set the parent of the insert actions explicitly.
2418 -- This is not a syntactic field, but we need the
2419 -- parent field set, in particular so that freeze
2420 -- can understand that it is dealing with condition
2421 -- actions, and properly insert the freezing actions.
2422
2423 Set_Parent (Ins_Actions, P);
2424 Analyze_List (Condition_Actions (P));
2425 end if;
2426
2427 return;
2428 end if;
2429
bebbff91 2430 -- Statements, declarations, pragmas, representation clauses
70482933
RK		 2431
2432 when
2433 -- Statements
2434
2435 N_Procedure_Call_Statement |
2436 N_Statement_Other_Than_Procedure_Call |
2437
2438 -- Pragmas
2439
2440 N_Pragma |
2441
2442 -- Representation_Clause
2443
2444 N_At_Clause |
2445 N_Attribute_Definition_Clause |
2446 N_Enumeration_Representation_Clause |
2447 N_Record_Representation_Clause |
2448
2449 -- Declarations
2450
2451 N_Abstract_Subprogram_Declaration |
2452 N_Entry_Body |
2453 N_Exception_Declaration |
2454 N_Exception_Renaming_Declaration |
82c80734
RD		 2455 N_Formal_Abstract_Subprogram_Declaration |
2456 N_Formal_Concrete_Subprogram_Declaration |
70482933 2457 N_Formal_Object_Declaration |
70482933
RK		 2458 N_Formal_Type_Declaration |
2459 N_Full_Type_Declaration |
2460 N_Function_Instantiation |
2461 N_Generic_Function_Renaming_Declaration |
2462 N_Generic_Package_Declaration |
2463 N_Generic_Package_Renaming_Declaration |
2464 N_Generic_Procedure_Renaming_Declaration |
2465 N_Generic_Subprogram_Declaration |
2466 N_Implicit_Label_Declaration |
2467 N_Incomplete_Type_Declaration |
2468 N_Number_Declaration |
2469 N_Object_Declaration |
2470 N_Object_Renaming_Declaration |
2471 N_Package_Body |
2472 N_Package_Body_Stub |
2473 N_Package_Declaration |
2474 N_Package_Instantiation |
2475 N_Package_Renaming_Declaration |
2476 N_Private_Extension_Declaration |
2477 N_Private_Type_Declaration |
2478 N_Procedure_Instantiation |
19590d70 2479 N_Protected_Body |
70482933
RK		 2480 N_Protected_Body_Stub |
2481 N_Protected_Type_Declaration |
2482 N_Single_Task_Declaration |
2483 N_Subprogram_Body |
2484 N_Subprogram_Body_Stub |
2485 N_Subprogram_Declaration |
2486 N_Subprogram_Renaming_Declaration |
2487 N_Subtype_Declaration |
2488 N_Task_Body |
2489 N_Task_Body_Stub |
2490 N_Task_Type_Declaration |
2491
2492 -- Freeze entity behaves like a declaration or statement
2493
2494 N_Freeze_Entity
2495 =>
2496 -- Do not insert here if the item is not a list member (this
2497 -- happens for example with a triggering statement, and the
2498 -- proper approach is to insert before the entire select).
2499
2500 if not Is_List_Member (P) then
2501 null;
2502
2503 -- Do not insert if parent of P is an N_Component_Association
05350ac6
BD		 2504 -- node (i.e. we are in the context of an N_Aggregate or
2505 -- N_Extension_Aggregate node. In this case we want to insert
2506 -- before the entire aggregate.
70482933
RK		 2507
2508 elsif Nkind (Parent (P)) = N_Component_Association then
2509 null;
2510
2511 -- Do not insert if the parent of P is either an N_Variant
2512 -- node or an N_Record_Definition node, meaning in either
2513 -- case that P is a member of a component list, and that
2514 -- therefore the actions should be inserted outside the
2515 -- complete record declaration.
2516
2517 elsif Nkind (Parent (P)) = N_Variant
2518 or else Nkind (Parent (P)) = N_Record_Definition
2519 then
2520 null;
2521
2522 -- Do not insert freeze nodes within the loop generated for
2523 -- an aggregate, because they may be elaborated too late for
2524 -- subsequent use in the back end: within a package spec the
2525 -- loop is part of the elaboration procedure and is only
2526 -- elaborated during the second pass.
2527 -- If the loop comes from source, or the entity is local to
2528 -- the loop itself it must remain within.
2529
2530 elsif Nkind (Parent (P)) = N_Loop_Statement
2531 and then not Comes_From_Source (Parent (P))
2532 and then Nkind (First (Ins_Actions)) = N_Freeze_Entity
2533 and then
2534 Scope (Entity (First (Ins_Actions))) /= Current_Scope
2535 then
2536 null;
2537
2538 -- Otherwise we can go ahead and do the insertion
2539
05350ac6 2540 elsif P = Wrapped_Node then
70482933
RK		 2541 Store_Before_Actions_In_Scope (Ins_Actions);
2542 return;
2543
2544 else
2545 Insert_List_Before_And_Analyze (P, Ins_Actions);
2546 return;
2547 end if;
2548
2549 -- A special case, N_Raise_xxx_Error can act either as a
2550 -- statement or a subexpression. We tell the difference
2551 -- by looking at the Etype. It is set to Standard_Void_Type
2552 -- in the statement case.
2553
2554 when
2555 N_Raise_xxx_Error =>
2556 if Etype (P) = Standard_Void_Type then
2557 if P = Wrapped_Node then
2558 Store_Before_Actions_In_Scope (Ins_Actions);
2559 else
2560 Insert_List_Before_And_Analyze (P, Ins_Actions);
2561 end if;
2562
2563 return;
2564
2565 -- In the subexpression case, keep climbing
2566
2567 else
2568 null;
2569 end if;
2570
2571 -- If a component association appears within a loop created for
2572 -- an array aggregate, attach the actions to the association so
2573 -- they can be subsequently inserted within the loop. For other
fbf5a39b
AC		 2574 -- component associations insert outside of the aggregate. For
2575 -- an association that will generate a loop, its Loop_Actions
2576 -- attribute is already initialized (see exp_aggr.adb).
70482933
RK		 2577
2578 -- The list of loop_actions can in turn generate additional ones,
2579 -- that are inserted before the associated node. If the associated
2580 -- node is outside the aggregate, the new actions are collected
2581 -- at the end of the loop actions, to respect the order in which
2582 -- they are to be elaborated.
2583
2584 when
2585 N_Component_Association =>
2586 if Nkind (Parent (P)) = N_Aggregate
fbf5a39b 2587 and then Present (Loop_Actions (P))
70482933 2588 then
fbf5a39b 2589 if Is_Empty_List (Loop_Actions (P)) then
70482933
RK		 2590 Set_Loop_Actions (P, Ins_Actions);
2591 Analyze_List (Ins_Actions);
2592
2593 else
2594 declare
bebbff91 2595 Decl : Node_Id;
70482933
RK		 2596
2597 begin
2598 -- Check whether these actions were generated
2599 -- by a declaration that is part of the loop_
2600 -- actions for the component_association.
2601
bebbff91 2602 Decl := Assoc_Node;
70482933
RK		 2603 while Present (Decl) loop
2604 exit when Parent (Decl) = P
2605 and then Is_List_Member (Decl)
2606 and then
2607 List_Containing (Decl) = Loop_Actions (P);
2608 Decl := Parent (Decl);
2609 end loop;
2610
2611 if Present (Decl) then
2612 Insert_List_Before_And_Analyze
2613 (Decl, Ins_Actions);
2614 else
2615 Insert_List_After_And_Analyze
2616 (Last (Loop_Actions (P)), Ins_Actions);
2617 end if;
2618 end;
2619 end if;
2620
2621 return;
2622
2623 else
2624 null;
2625 end if;
2626
2627 -- Another special case, an attribute denoting a procedure call
2628
2629 when
2630 N_Attribute_Reference =>
2631 if Is_Procedure_Attribute_Name (Attribute_Name (P)) then
2632 if P = Wrapped_Node then
2633 Store_Before_Actions_In_Scope (Ins_Actions);
2634 else
2635 Insert_List_Before_And_Analyze (P, Ins_Actions);
2636 end if;
2637
2638 return;
2639
2640 -- In the subexpression case, keep climbing
2641
2642 else
2643 null;
2644 end if;
2645
2646 -- For all other node types, keep climbing tree
2647
2648 when
2649 N_Abortable_Part |
2650 N_Accept_Alternative |
2651 N_Access_Definition |
2652 N_Access_Function_Definition |
2653 N_Access_Procedure_Definition |
2654 N_Access_To_Object_Definition |
2655 N_Aggregate |
2656 N_Allocator |
2657 N_Case_Statement_Alternative |
2658 N_Character_Literal |
2659 N_Compilation_Unit |
2660 N_Compilation_Unit_Aux |
2661 N_Component_Clause |
2662 N_Component_Declaration |
a397db96 2663 N_Component_Definition |
70482933
RK		 2664 N_Component_List |
2665 N_Constrained_Array_Definition |
2666 N_Decimal_Fixed_Point_Definition |
2667 N_Defining_Character_Literal |
2668 N_Defining_Identifier |
2669 N_Defining_Operator_Symbol |
2670 N_Defining_Program_Unit_Name |
2671 N_Delay_Alternative |
2672 N_Delta_Constraint |
2673 N_Derived_Type_Definition |
2674 N_Designator |
2675 N_Digits_Constraint |
2676 N_Discriminant_Association |
2677 N_Discriminant_Specification |
2678 N_Empty |
2679 N_Entry_Body_Formal_Part |
2680 N_Entry_Call_Alternative |
2681 N_Entry_Declaration |
2682 N_Entry_Index_Specification |
2683 N_Enumeration_Type_Definition |
2684 N_Error |
2685 N_Exception_Handler |
2686 N_Expanded_Name |
2687 N_Explicit_Dereference |
2688 N_Extension_Aggregate |
2689 N_Floating_Point_Definition |
2690 N_Formal_Decimal_Fixed_Point_Definition |
2691 N_Formal_Derived_Type_Definition |
2692 N_Formal_Discrete_Type_Definition |
2693 N_Formal_Floating_Point_Definition |
2694 N_Formal_Modular_Type_Definition |
2695 N_Formal_Ordinary_Fixed_Point_Definition |
2696 N_Formal_Package_Declaration |
2697 N_Formal_Private_Type_Definition |
2698 N_Formal_Signed_Integer_Type_Definition |
2699 N_Function_Call |
2700 N_Function_Specification |
2701 N_Generic_Association |
2702 N_Handled_Sequence_Of_Statements |
2703 N_Identifier |
2704 N_In |
2705 N_Index_Or_Discriminant_Constraint |
2706 N_Indexed_Component |
2707 N_Integer_Literal |
2708 N_Itype_Reference |
2709 N_Label |
2710 N_Loop_Parameter_Specification |
2711 N_Mod_Clause |
2712 N_Modular_Type_Definition |
2713 N_Not_In |
2714 N_Null |
2715 N_Op_Abs |
2716 N_Op_Add |
2717 N_Op_And |
2718 N_Op_Concat |
2719 N_Op_Divide |
2720 N_Op_Eq |
2721 N_Op_Expon |
2722 N_Op_Ge |
2723 N_Op_Gt |
2724 N_Op_Le |
2725 N_Op_Lt |
2726 N_Op_Minus |
2727 N_Op_Mod |
2728 N_Op_Multiply |
2729 N_Op_Ne |
2730 N_Op_Not |
2731 N_Op_Or |
2732 N_Op_Plus |
2733 N_Op_Rem |
2734 N_Op_Rotate_Left |
2735 N_Op_Rotate_Right |
2736 N_Op_Shift_Left |
2737 N_Op_Shift_Right |
2738 N_Op_Shift_Right_Arithmetic |
2739 N_Op_Subtract |
2740 N_Op_Xor |
2741 N_Operator_Symbol |
2742 N_Ordinary_Fixed_Point_Definition |
2743 N_Others_Choice |
2744 N_Package_Specification |
2745 N_Parameter_Association |
2746 N_Parameter_Specification |
dee4682a
JM		 2747 N_Pop_Constraint_Error_Label |
2748 N_Pop_Program_Error_Label |
2749 N_Pop_Storage_Error_Label |
70482933
RK		 2750 N_Pragma_Argument_Association |
2751 N_Procedure_Specification |
70482933 2752 N_Protected_Definition |
dee4682a
JM		 2753 N_Push_Constraint_Error_Label |
2754 N_Push_Program_Error_Label |
2755 N_Push_Storage_Error_Label |
70482933
RK		 2756 N_Qualified_Expression |
2757 N_Range |
2758 N_Range_Constraint |
2759 N_Real_Literal |
2760 N_Real_Range_Specification |
2761 N_Record_Definition |
2762 N_Reference |
2763 N_Selected_Component |
2764 N_Signed_Integer_Type_Definition |
2765 N_Single_Protected_Declaration |
2766 N_Slice |
2767 N_String_Literal |
2768 N_Subprogram_Info |
2769 N_Subtype_Indication |
2770 N_Subunit |
2771 N_Task_Definition |
2772 N_Terminate_Alternative |
2773 N_Triggering_Alternative |
2774 N_Type_Conversion |
2775 N_Unchecked_Expression |
2776 N_Unchecked_Type_Conversion |
2777 N_Unconstrained_Array_Definition |
2778 N_Unused_At_End |
2779 N_Unused_At_Start |
2780 N_Use_Package_Clause |
2781 N_Use_Type_Clause |
2782 N_Variant |
2783 N_Variant_Part |
2784 N_Validate_Unchecked_Conversion |
0712790c 2785 N_With_Clause
70482933
RK		 2786 =>
2787 null;
2788
2789 end case;
2790
2791 -- Make sure that inserted actions stay in the transient scope
2792
2793 if P = Wrapped_Node then
2794 Store_Before_Actions_In_Scope (Ins_Actions);
2795 return;
2796 end if;
2797
2798 -- If we fall through above tests, keep climbing tree
2799
2800 N := P;
2801
2802 if Nkind (Parent (N)) = N_Subunit then
2803
2804 -- This is the proper body corresponding to a stub. Insertion
2805 -- must be done at the point of the stub, which is in the decla-
2806 -- tive part of the parent unit.
2807
2808 P := Corresponding_Stub (Parent (N));
2809
2810 else
2811 P := Parent (N);
2812 end if;
2813 end loop;
70482933
RK		 2814 end Insert_Actions;
2815
2816 -- Version with check(s) suppressed
2817
2818 procedure Insert_Actions
0712790c
ES		 2819 (Assoc_Node : Node_Id;
2820 Ins_Actions : List_Id;
2821 Suppress : Check_Id)
70482933
RK		 2822 is
2823 begin
2824 if Suppress = All_Checks then
2825 declare
fbf5a39b 2826 Svg : constant Suppress_Array := Scope_Suppress;
70482933
RK		 2827 begin
2828 Scope_Suppress := (others => True);
2829 Insert_Actions (Assoc_Node, Ins_Actions);
2830 Scope_Suppress := Svg;
2831 end;
2832
2833 else
2834 declare
fbf5a39b 2835 Svg : constant Boolean := Scope_Suppress (Suppress);
70482933 2836 begin
fbf5a39b 2837 Scope_Suppress (Suppress) := True;
70482933 2838 Insert_Actions (Assoc_Node, Ins_Actions);
fbf5a39b 2839 Scope_Suppress (Suppress) := Svg;
70482933
RK		 2840 end;
2841 end if;
2842 end Insert_Actions;
2843
2844 --------------------------
2845 -- Insert_Actions_After --
2846 --------------------------
2847
2848 procedure Insert_Actions_After
2849 (Assoc_Node : Node_Id;
2850 Ins_Actions : List_Id)
2851 is
2852 begin
2853 if Scope_Is_Transient
2854 and then Assoc_Node = Node_To_Be_Wrapped
2855 then
2856 Store_After_Actions_In_Scope (Ins_Actions);
2857 else
2858 Insert_List_After_And_Analyze (Assoc_Node, Ins_Actions);
2859 end if;
2860 end Insert_Actions_After;
2861
2862 ---------------------------------
2863 -- Insert_Library_Level_Action --
2864 ---------------------------------
2865
2866 procedure Insert_Library_Level_Action (N : Node_Id) is
2867 Aux : constant Node_Id := Aux_Decls_Node (Cunit (Main_Unit));
2868
2869 begin
0712790c
ES		 2870 Push_Scope (Cunit_Entity (Main_Unit));
2871 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
70482933
RK		 2872
2873 if No (Actions (Aux)) then
2874 Set_Actions (Aux, New_List (N));
2875 else
2876 Append (N, Actions (Aux));
2877 end if;
2878
2879 Analyze (N);
2880 Pop_Scope;
2881 end Insert_Library_Level_Action;
2882
2883 ----------------------------------
2884 -- Insert_Library_Level_Actions --
2885 ----------------------------------
2886
2887 procedure Insert_Library_Level_Actions (L : List_Id) is
2888 Aux : constant Node_Id := Aux_Decls_Node (Cunit (Main_Unit));
2889
2890 begin
2891 if Is_Non_Empty_List (L) then
0712790c
ES		 2892 Push_Scope (Cunit_Entity (Main_Unit));
2893 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
70482933
RK		 2894
2895 if No (Actions (Aux)) then
2896 Set_Actions (Aux, L);
2897 Analyze_List (L);
2898 else
2899 Insert_List_After_And_Analyze (Last (Actions (Aux)), L);
2900 end if;
2901
2902 Pop_Scope;
2903 end if;
2904 end Insert_Library_Level_Actions;
2905
2906 ----------------------
2907 -- Inside_Init_Proc --
2908 ----------------------
2909
2910 function Inside_Init_Proc return Boolean is
2911 S : Entity_Id;
2912
2913 begin
2914 S := Current_Scope;
fbf5a39b
AC		 2915 while Present (S)
2916 and then S /= Standard_Standard
2917 loop
2918 if Is_Init_Proc (S) then
70482933
RK		 2919 return True;
2920 else
2921 S := Scope (S);
2922 end if;
2923 end loop;
2924
2925 return False;
2926 end Inside_Init_Proc;
2927
fbf5a39b
AC		 2928 ----------------------------
2929 -- Is_All_Null_Statements --
2930 ----------------------------
2931
2932 function Is_All_Null_Statements (L : List_Id) return Boolean is
2933 Stm : Node_Id;
2934
2935 begin
2936 Stm := First (L);
2937 while Present (Stm) loop
2938 if Nkind (Stm) /= N_Null_Statement then
2939 return False;
2940 end if;
2941
2942 Next (Stm);
2943 end loop;
2944
2945 return True;
2946 end Is_All_Null_Statements;
2947
86cde7b1
RD		 2948 ----------------------------------
2949 -- Is_Library_Level_Tagged_Type --
2950 ----------------------------------
2951
2952 function Is_Library_Level_Tagged_Type (Typ : Entity_Id) return Boolean is
2953 begin
2954 return Is_Tagged_Type (Typ)
2955 and then Is_Library_Level_Entity (Typ);
2956 end Is_Library_Level_Tagged_Type;
2957
f4d379b8
HK		 2958 -----------------------------------------
2959 -- Is_Predefined_Dispatching_Operation --
2960 -----------------------------------------
758c442c 2961
59e54267 2962 function Is_Predefined_Dispatching_Operation (E : Entity_Id) return Boolean
758c442c
GD		 2963 is
2964 TSS_Name : TSS_Name_Type;
758c442c 2965
59e54267
ES		 2966 begin
2967 if not Is_Dispatching_Operation (E) then
2968 return False;
2969 end if;
758c442c
GD		 2970
2971 Get_Name_String (Chars (E));
2972
2973 if Name_Len > TSS_Name_Type'Last then
2974 TSS_Name := TSS_Name_Type (Name_Buffer (Name_Len - TSS_Name'Length + 1
2975 .. Name_Len));
2976 if Chars (E) = Name_uSize
2977 or else Chars (E) = Name_uAlignment
2978 or else TSS_Name = TSS_Stream_Read
2979 or else TSS_Name = TSS_Stream_Write
2980 or else TSS_Name = TSS_Stream_Input
2981 or else TSS_Name = TSS_Stream_Output
59e54267
ES		 2982 or else
2983 (Chars (E) = Name_Op_Eq
2984 and then Etype (First_Entity (E)) = Etype (Last_Entity (E)))
758c442c
GD		 2985 or else Chars (E) = Name_uAssign
2986 or else TSS_Name = TSS_Deep_Adjust
2987 or else TSS_Name = TSS_Deep_Finalize
f4d379b8
HK		 2988 or else (Ada_Version >= Ada_05
2989 and then (Chars (E) = Name_uDisp_Asynchronous_Select
2990 or else Chars (E) = Name_uDisp_Conditional_Select
2991 or else Chars (E) = Name_uDisp_Get_Prim_Op_Kind
2992 or else Chars (E) = Name_uDisp_Get_Task_Id
2993 or else Chars (E) = Name_uDisp_Timed_Select))
758c442c
GD		 2994 then
2995 return True;
2996 end if;
2997 end if;
2998
2999 return False;
3000 end Is_Predefined_Dispatching_Operation;
3001
fbf5a39b
AC		 3002 ----------------------------------
3003 -- Is_Possibly_Unaligned_Object --
3004 ----------------------------------
3005
f44fe430
RD		 3006 function Is_Possibly_Unaligned_Object (N : Node_Id) return Boolean is
3007 T : constant Entity_Id := Etype (N);
3008
fbf5a39b 3009 begin
f44fe430 3010 -- If renamed object, apply test to underlying object
fbf5a39b 3011
f44fe430
RD		 3012 if Is_Entity_Name (N)
3013 and then Is_Object (Entity (N))
3014 and then Present (Renamed_Object (Entity (N)))
3015 then
3016 return Is_Possibly_Unaligned_Object (Renamed_Object (Entity (N)));
fbf5a39b
AC		 3017 end if;
3018
f44fe430
RD		 3019 -- Tagged and controlled types and aliased types are always aligned,
3020 -- as are concurrent types.
fbf5a39b 3021
f44fe430
RD		 3022 if Is_Aliased (T)
3023 or else Has_Controlled_Component (T)
3024 or else Is_Concurrent_Type (T)
3025 or else Is_Tagged_Type (T)
3026 or else Is_Controlled (T)
fbf5a39b 3027 then
f44fe430 3028 return False;
fbf5a39b
AC		 3029 end if;
3030
3031 -- If this is an element of a packed array, may be unaligned
3032
f44fe430 3033 if Is_Ref_To_Bit_Packed_Array (N) then
fbf5a39b
AC		 3034 return True;
3035 end if;
3036
3037 -- Case of component reference
3038
f44fe430
RD		 3039 if Nkind (N) = N_Selected_Component then
3040 declare
3041 P : constant Node_Id := Prefix (N);
3042 C : constant Entity_Id := Entity (Selector_Name (N));
3043 M : Nat;
3044 S : Nat;
fbf5a39b 3045
f44fe430
RD		 3046 begin
3047 -- If component reference is for an array with non-static bounds,
758c442c
GD		 3048 -- then it is always aligned: we can only process unaligned
3049 -- arrays with static bounds (more accurately bounds known at
3050 -- compile time).
fbf5a39b 3051
f44fe430
RD		 3052 if Is_Array_Type (T)
3053 and then not Compile_Time_Known_Bounds (T)
3054 then
3055 return False;
3056 end if;
fbf5a39b 3057
f44fe430 3058 -- If component is aliased, it is definitely properly aligned
fbf5a39b 3059
f44fe430
RD		 3060 if Is_Aliased (C) then
3061 return False;
3062 end if;
3063
3064 -- If component is for a type implemented as a scalar, and the
3065 -- record is packed, and the component is other than the first
3066 -- component of the record, then the component may be unaligned.
3067
3068 if Is_Packed (Etype (P))
8adcacef
RD		 3069 and then Represented_As_Scalar (Etype (C))
3070 and then First_Entity (Scope (C)) /= C
f44fe430
RD		 3071 then
3072 return True;
3073 end if;
3074
3075 -- Compute maximum possible alignment for T
3076
3077 -- If alignment is known, then that settles things
3078
3079 if Known_Alignment (T) then
3080 M := UI_To_Int (Alignment (T));
3081
3082 -- If alignment is not known, tentatively set max alignment
3083
3084 else
3085 M := Ttypes.Maximum_Alignment;
3086
3087 -- We can reduce this if the Esize is known since the default
3088 -- alignment will never be more than the smallest power of 2
3089 -- that does not exceed this Esize value.
3090
3091 if Known_Esize (T) then
3092 S := UI_To_Int (Esize (T));
3093
3094 while (M / 2) >= S loop
3095 M := M / 2;
3096 end loop;
3097 end if;
3098 end if;
3099
3100 -- If the component reference is for a record that has a specified
3101 -- alignment, and we either know it is too small, or cannot tell,
3102 -- then the component may be unaligned
3103
3104 if Known_Alignment (Etype (P))
3105 and then Alignment (Etype (P)) < Ttypes.Maximum_Alignment
3106 and then M > Alignment (Etype (P))
3107 then
3108 return True;
3109 end if;
3110
3111 -- Case of component clause present which may specify an
3112 -- unaligned position.
3113
3114 if Present (Component_Clause (C)) then
3115
3116 -- Otherwise we can do a test to make sure that the actual
3117 -- start position in the record, and the length, are both
3118 -- consistent with the required alignment. If not, we know
3119 -- that we are unaligned.
3120
3121 declare
3122 Align_In_Bits : constant Nat := M * System_Storage_Unit;
3123 begin
3124 if Component_Bit_Offset (C) mod Align_In_Bits /= 0
3125 or else Esize (C) mod Align_In_Bits /= 0
3126 then
3127 return True;
3128 end if;
3129 end;
3130 end if;
3131
3132 -- Otherwise, for a component reference, test prefix
3133
3134 return Is_Possibly_Unaligned_Object (P);
3135 end;
fbf5a39b
AC		 3136
3137 -- If not a component reference, must be aligned
3138
3139 else
3140 return False;
3141 end if;
3142 end Is_Possibly_Unaligned_Object;
3143
3144 ---------------------------------
3145 -- Is_Possibly_Unaligned_Slice --
3146 ---------------------------------
3147
f44fe430 3148 function Is_Possibly_Unaligned_Slice (N : Node_Id) return Boolean is
fbf5a39b 3149 begin
0712790c 3150 -- Go to renamed object
246d2ceb 3151
f44fe430
RD		 3152 if Is_Entity_Name (N)
3153 and then Is_Object (Entity (N))
3154 and then Present (Renamed_Object (Entity (N)))
fbf5a39b 3155 then
f44fe430 3156 return Is_Possibly_Unaligned_Slice (Renamed_Object (Entity (N)));
fbf5a39b
AC		 3157 end if;
3158
246d2ceb 3159 -- The reference must be a slice
fbf5a39b 3160
f44fe430 3161 if Nkind (N) /= N_Slice then
246d2ceb 3162 return False;
fbf5a39b
AC		 3163 end if;
3164
246d2ceb
AC		 3165 -- Always assume the worst for a nested record component with a
3166 -- component clause, which gigi/gcc does not appear to handle well.
3167 -- It is not clear why this special test is needed at all ???
fbf5a39b 3168
f44fe430
RD		 3169 if Nkind (Prefix (N)) = N_Selected_Component
3170 and then Nkind (Prefix (Prefix (N))) = N_Selected_Component
246d2ceb 3171 and then
f44fe430 3172 Present (Component_Clause (Entity (Selector_Name (Prefix (N)))))
246d2ceb
AC		 3173 then
3174 return True;
3175 end if;
3176
3177 -- We only need to worry if the target has strict alignment
3178
3179 if not Target_Strict_Alignment then
fbf5a39b
AC		 3180 return False;
3181 end if;
3182
3183 -- If it is a slice, then look at the array type being sliced
3184
3185 declare
f44fe430 3186 Sarr : constant Node_Id := Prefix (N);
246d2ceb
AC		 3187 -- Prefix of the slice, i.e. the array being sliced
3188
f44fe430 3189 Styp : constant Entity_Id := Etype (Prefix (N));
246d2ceb
AC		 3190 -- Type of the array being sliced
3191
3192 Pref : Node_Id;
3193 Ptyp : Entity_Id;
fbf5a39b
AC		 3194
3195 begin
246d2ceb
AC		 3196 -- The problems arise if the array object that is being sliced
3197 -- is a component of a record or array, and we cannot guarantee
3198 -- the alignment of the array within its containing object.
fbf5a39b 3199
246d2ceb
AC		 3200 -- To investigate this, we look at successive prefixes to see
3201 -- if we have a worrisome indexed or selected component.
fbf5a39b 3202
246d2ceb
AC		 3203 Pref := Sarr;
3204 loop
3205 -- Case of array is part of an indexed component reference
fbf5a39b 3206
246d2ceb
AC		 3207 if Nkind (Pref) = N_Indexed_Component then
3208 Ptyp := Etype (Prefix (Pref));
3209
3210 -- The only problematic case is when the array is packed,
3211 -- in which case we really know nothing about the alignment
3212 -- of individual components.
3213
3214 if Is_Bit_Packed_Array (Ptyp) then
3215 return True;
3216 end if;
3217
3218 -- Case of array is part of a selected component reference
3219
3220 elsif Nkind (Pref) = N_Selected_Component then
3221 Ptyp := Etype (Prefix (Pref));
3222
3223 -- We are definitely in trouble if the record in question
3224 -- has an alignment, and either we know this alignment is
3225 -- inconsistent with the alignment of the slice, or we
3226 -- don't know what the alignment of the slice should be.
3227
3228 if Known_Alignment (Ptyp)
3229 and then (Unknown_Alignment (Styp)
3230 or else Alignment (Styp) > Alignment (Ptyp))
3231 then
3232 return True;
3233 end if;
3234
3235 -- We are in potential trouble if the record type is packed.
3236 -- We could special case when we know that the array is the
3237 -- first component, but that's not such a simple case ???
3238
3239 if Is_Packed (Ptyp) then
3240 return True;
3241 end if;
3242
3243 -- We are in trouble if there is a component clause, and
3244 -- either we do not know the alignment of the slice, or
3245 -- the alignment of the slice is inconsistent with the
3246 -- bit position specified by the component clause.
3247
3248 declare
3249 Field : constant Entity_Id := Entity (Selector_Name (Pref));
3250 begin
3251 if Present (Component_Clause (Field))
3252 and then
3253 (Unknown_Alignment (Styp)
3254 or else
3255 (Component_Bit_Offset (Field) mod
3256 (System_Storage_Unit * Alignment (Styp))) /= 0)
3257 then
3258 return True;
3259 end if;
3260 end;
3261
3262 -- For cases other than selected or indexed components we
3263 -- know we are OK, since no issues arise over alignment.
3264
3265 else
3266 return False;
3267 end if;
3268
3269 -- We processed an indexed component or selected component
3270 -- reference that looked safe, so keep checking prefixes.
3271
3272 Pref := Prefix (Pref);
3273 end loop;
fbf5a39b
AC		 3274 end;
3275 end Is_Possibly_Unaligned_Slice;
3276
70482933
RK		 3277 --------------------------------
3278 -- Is_Ref_To_Bit_Packed_Array --
3279 --------------------------------
3280
f44fe430 3281 function Is_Ref_To_Bit_Packed_Array (N : Node_Id) return Boolean is
70482933
RK		 3282 Result : Boolean;
3283 Expr : Node_Id;
3284
3285 begin
f44fe430
RD		 3286 if Is_Entity_Name (N)
3287 and then Is_Object (Entity (N))
3288 and then Present (Renamed_Object (Entity (N)))
fbf5a39b 3289 then
f44fe430 3290 return Is_Ref_To_Bit_Packed_Array (Renamed_Object (Entity (N)));
fbf5a39b
AC		 3291 end if;
3292
f44fe430 3293 if Nkind (N) = N_Indexed_Component
70482933 3294 or else
f44fe430 3295 Nkind (N) = N_Selected_Component
70482933 3296 then
f44fe430 3297 if Is_Bit_Packed_Array (Etype (Prefix (N))) then
70482933
RK		 3298 Result := True;
3299 else
f44fe430 3300 Result := Is_Ref_To_Bit_Packed_Array (Prefix (N));
70482933
RK		 3301 end if;
3302
f44fe430
RD		 3303 if Result and then Nkind (N) = N_Indexed_Component then
3304 Expr := First (Expressions (N));
70482933
RK		 3305 while Present (Expr) loop
3306 Force_Evaluation (Expr);
3307 Next (Expr);
3308 end loop;
3309 end if;
3310
3311 return Result;
3312
3313 else
3314 return False;
3315 end if;
3316 end Is_Ref_To_Bit_Packed_Array;
3317
3318 --------------------------------
fbf5a39b 3319 -- Is_Ref_To_Bit_Packed_Slice --
70482933
RK		 3320 --------------------------------
3321
f44fe430 3322 function Is_Ref_To_Bit_Packed_Slice (N : Node_Id) return Boolean is
70482933 3323 begin
ea985d95
RD		 3324 if Nkind (N) = N_Type_Conversion then
3325 return Is_Ref_To_Bit_Packed_Slice (Expression (N));
3326
3327 elsif Is_Entity_Name (N)
f44fe430
RD		 3328 and then Is_Object (Entity (N))
3329 and then Present (Renamed_Object (Entity (N)))
fbf5a39b 3330 then
f44fe430 3331 return Is_Ref_To_Bit_Packed_Slice (Renamed_Object (Entity (N)));
fbf5a39b 3332
ea985d95 3333 elsif Nkind (N) = N_Slice
f44fe430 3334 and then Is_Bit_Packed_Array (Etype (Prefix (N)))
70482933
RK		 3335 then
3336 return True;
3337
f44fe430 3338 elsif Nkind (N) = N_Indexed_Component
70482933 3339 or else
f44fe430 3340 Nkind (N) = N_Selected_Component
70482933 3341 then
f44fe430 3342 return Is_Ref_To_Bit_Packed_Slice (Prefix (N));
70482933
RK		 3343
3344 else
3345 return False;
3346 end if;
3347 end Is_Ref_To_Bit_Packed_Slice;
3348
3349 -----------------------
3350 -- Is_Renamed_Object --
3351 -----------------------
3352
3353 function Is_Renamed_Object (N : Node_Id) return Boolean is
3354 Pnod : constant Node_Id := Parent (N);
3355 Kind : constant Node_Kind := Nkind (Pnod);
3356
3357 begin
3358 if Kind = N_Object_Renaming_Declaration then
3359 return True;
3360
3361 elsif Kind = N_Indexed_Component
3362 or else Kind = N_Selected_Component
3363 then
3364 return Is_Renamed_Object (Pnod);
3365
3366 else
3367 return False;
3368 end if;
3369 end Is_Renamed_Object;
3370
3371 ----------------------------
3372 -- Is_Untagged_Derivation --
3373 ----------------------------
3374
3375 function Is_Untagged_Derivation (T : Entity_Id) return Boolean is
3376 begin
3377 return (not Is_Tagged_Type (T) and then Is_Derived_Type (T))
3378 or else
3379 (Is_Private_Type (T) and then Present (Full_View (T))
3380 and then not Is_Tagged_Type (Full_View (T))
3381 and then Is_Derived_Type (Full_View (T))
3382 and then Etype (Full_View (T)) /= T);
70482933
RK		 3383 end Is_Untagged_Derivation;
3384
3385 --------------------
3386 -- Kill_Dead_Code --
3387 --------------------
3388
05350ac6 3389 procedure Kill_Dead_Code (N : Node_Id; Warn : Boolean := False) is
70482933
RK		 3390 begin
3391 if Present (N) then
70482933
RK		 3392 Remove_Warning_Messages (N);
3393
05350ac6
BD		 3394 if Warn then
3395 Error_Msg_F
86cde7b1 3396 ("?this code can never be executed and has been deleted!", N);
05350ac6
BD		 3397 end if;
3398
07fc65c4
GB		 3399 -- Recurse into block statements and bodies to process declarations
3400 -- and statements
70482933 3401
07fc65c4
GB		 3402 if Nkind (N) = N_Block_Statement
3403 or else Nkind (N) = N_Subprogram_Body
3404 or else Nkind (N) = N_Package_Body
3405 then
05350ac6
BD		 3406 Kill_Dead_Code
3407 (Declarations (N), False);
3408 Kill_Dead_Code
3409 (Statements (Handled_Statement_Sequence (N)));
70482933 3410
07fc65c4
GB		 3411 if Nkind (N) = N_Subprogram_Body then
3412 Set_Is_Eliminated (Defining_Entity (N));
3413 end if;
3414
f44fe430
RD		 3415 elsif Nkind (N) = N_Package_Declaration then
3416 Kill_Dead_Code (Visible_Declarations (Specification (N)));
3417 Kill_Dead_Code (Private_Declarations (Specification (N)));
3418
3419 declare
3420 E : Entity_Id := First_Entity (Defining_Entity (N));
3421 begin
3422 while Present (E) loop
3423 if Ekind (E) = E_Operator then
3424 Set_Is_Eliminated (E);
3425 end if;
3426
3427 Next_Entity (E);
3428 end loop;
3429 end;
3430
70482933
RK		 3431 -- Recurse into composite statement to kill individual statements,
3432 -- in particular instantiations.
3433
3434 elsif Nkind (N) = N_If_Statement then
3435 Kill_Dead_Code (Then_Statements (N));
3436 Kill_Dead_Code (Elsif_Parts (N));
3437 Kill_Dead_Code (Else_Statements (N));
3438
3439 elsif Nkind (N) = N_Loop_Statement then
3440 Kill_Dead_Code (Statements (N));
3441
3442 elsif Nkind (N) = N_Case_Statement then
3443 declare
bebbff91 3444 Alt : Node_Id;
70482933 3445 begin
bebbff91 3446 Alt := First (Alternatives (N));
70482933
RK		 3447 while Present (Alt) loop
3448 Kill_Dead_Code (Statements (Alt));
3449 Next (Alt);
3450 end loop;
3451 end;
3452
fbf5a39b
AC		 3453 elsif Nkind (N) = N_Case_Statement_Alternative then
3454 Kill_Dead_Code (Statements (N));
3455
70482933
RK		 3456 -- Deal with dead instances caused by deleting instantiations
3457
3458 elsif Nkind (N) in N_Generic_Instantiation then
3459 Remove_Dead_Instance (N);
3460 end if;
3461
3462 Delete_Tree (N);
3463 end if;
3464 end Kill_Dead_Code;
3465
3466 -- Case where argument is a list of nodes to be killed
3467
05350ac6 3468 procedure Kill_Dead_Code (L : List_Id; Warn : Boolean := False) is
70482933 3469 N : Node_Id;
05350ac6 3470 W : Boolean;
70482933 3471 begin
05350ac6 3472 W := Warn;
70482933
RK		 3473 if Is_Non_Empty_List (L) then
3474 loop
3475 N := Remove_Head (L);
3476 exit when No (N);
05350ac6
BD		 3477 Kill_Dead_Code (N, W);
3478 W := False;
70482933
RK		 3479 end loop;
3480 end if;
3481 end Kill_Dead_Code;
3482
3483 ------------------------
3484 -- Known_Non_Negative --
3485 ------------------------
3486
3487 function Known_Non_Negative (Opnd : Node_Id) return Boolean is
3488 begin
3489 if Is_OK_Static_Expression (Opnd)
3490 and then Expr_Value (Opnd) >= 0
3491 then
3492 return True;
3493
3494 else
3495 declare
3496 Lo : constant Node_Id := Type_Low_Bound (Etype (Opnd));
3497
3498 begin
3499 return
3500 Is_OK_Static_Expression (Lo) and then Expr_Value (Lo) >= 0;
3501 end;
3502 end if;
3503 end Known_Non_Negative;
3504
fbf5a39b
AC		 3505 --------------------
3506 -- Known_Non_Null --
3507 --------------------
07fc65c4 3508
fbf5a39b
AC		 3509 function Known_Non_Null (N : Node_Id) return Boolean is
3510 begin
59e54267 3511 -- Checks for case where N is an entity reference
07fc65c4 3512
59e54267
ES		 3513 if Is_Entity_Name (N) and then Present (Entity (N)) then
3514 declare
3515 E : constant Entity_Id := Entity (N);
3516 Op : Node_Kind;
3517 Val : Node_Id;
07fc65c4 3518
59e54267
ES		 3519 begin
3520 -- First check if we are in decisive conditional
07fc65c4 3521
59e54267 3522 Get_Current_Value_Condition (N, Op, Val);
07fc65c4 3523
86cde7b1 3524 if Known_Null (Val) then
59e54267
ES		 3525 if Op = N_Op_Eq then
3526 return False;
3527 elsif Op = N_Op_Ne then
3528 return True;
3529 end if;
3530 end if;
07fc65c4 3531
59e54267 3532 -- If OK to do replacement, test Is_Known_Non_Null flag
07fc65c4 3533
59e54267
ES		 3534 if OK_To_Do_Constant_Replacement (E) then
3535 return Is_Known_Non_Null (E);
3536
3537 -- Otherwise if not safe to do replacement, then say so
3538
3539 else
3540 return False;
3541 end if;
3542 end;
07fc65c4 3543
fbf5a39b 3544 -- True if access attribute
07fc65c4 3545
fbf5a39b
AC		 3546 elsif Nkind (N) = N_Attribute_Reference
3547 and then (Attribute_Name (N) = Name_Access
3548 or else
3549 Attribute_Name (N) = Name_Unchecked_Access
3550 or else
3551 Attribute_Name (N) = Name_Unrestricted_Access)
3552 then
3553 return True;
07fc65c4 3554
fbf5a39b 3555 -- True if allocator
07fc65c4 3556
fbf5a39b
AC		 3557 elsif Nkind (N) = N_Allocator then
3558 return True;
07fc65c4 3559
fbf5a39b 3560 -- For a conversion, true if expression is known non-null
07fc65c4 3561
fbf5a39b
AC		 3562 elsif Nkind (N) = N_Type_Conversion then
3563 return Known_Non_Null (Expression (N));
07fc65c4 3564
59e54267
ES		 3565 -- Above are all cases where the value could be determined to be
3566 -- non-null. In all other cases, we don't know, so return False.
07fc65c4 3567
59e54267
ES		 3568 else
3569 return False;
3570 end if;
3571 end Known_Non_Null;
3572
3573 ----------------
3574 -- Known_Null --
3575 ----------------
3576
3577 function Known_Null (N : Node_Id) return Boolean is
3578 begin
3579 -- Checks for case where N is an entity reference
3580
3581 if Is_Entity_Name (N) and then Present (Entity (N)) then
fbf5a39b 3582 declare
59e54267 3583 E : constant Entity_Id := Entity (N);
fbf5a39b
AC		 3584 Op : Node_Kind;
3585 Val : Node_Id;
07fc65c4 3586
fbf5a39b 3587 begin
86cde7b1
RD		 3588 -- Constant null value is for sure null
3589
3590 if Ekind (E) = E_Constant
3591 and then Known_Null (Constant_Value (E))
3592 then
3593 return True;
3594 end if;
3595
59e54267
ES		 3596 -- First check if we are in decisive conditional
3597
fbf5a39b 3598 Get_Current_Value_Condition (N, Op, Val);
59e54267 3599
86cde7b1 3600 if Known_Null (Val) then
59e54267
ES		 3601 if Op = N_Op_Eq then
3602 return True;
3603 elsif Op = N_Op_Ne then
3604 return False;
3605 end if;
3606 end if;
3607
3608 -- If OK to do replacement, test Is_Known_Null flag
3609
3610 if OK_To_Do_Constant_Replacement (E) then
3611 return Is_Known_Null (E);
3612
3613 -- Otherwise if not safe to do replacement, then say so
3614
3615 else
3616 return False;
3617 end if;
fbf5a39b
AC		 3618 end;
3619
59e54267
ES		 3620 -- True if explicit reference to null
3621
3622 elsif Nkind (N) = N_Null then
3623 return True;
3624
3625 -- For a conversion, true if expression is known null
3626
3627 elsif Nkind (N) = N_Type_Conversion then
3628 return Known_Null (Expression (N));
3629
3630 -- Above are all cases where the value could be determined to be null.
3631 -- In all other cases, we don't know, so return False.
fbf5a39b
AC		 3632
3633 else
3634 return False;
3635 end if;
59e54267 3636 end Known_Null;
07fc65c4 3637
70482933
RK		 3638 -----------------------------
3639 -- Make_CW_Equivalent_Type --
3640 -----------------------------
3641
3642 -- Create a record type used as an equivalent of any member
3643 -- of the class which takes its size from exp.
3644
3645 -- Generate the following code:
3646
3647 -- type Equiv_T is record
3648 -- _parent : T (List of discriminant constaints taken from Exp);
fbf5a39b 3649 -- Ext__50 : Storage_Array (1 .. (Exp'size - Typ'object_size)/8);
70482933 3650 -- end Equiv_T;
fbf5a39b
AC		 3651 --
3652 -- ??? Note that this type does not guarantee same alignment as all
3653 -- derived types
70482933
RK		 3654
3655 function Make_CW_Equivalent_Type
bebbff91
AC		 3656 (T : Entity_Id;
3657 E : Node_Id) return Entity_Id
70482933
RK		 3658 is
3659 Loc : constant Source_Ptr := Sloc (E);
3660 Root_Typ : constant Entity_Id := Root_Type (T);
fbf5a39b 3661 List_Def : constant List_Id := Empty_List;
0712790c 3662 Comp_List : constant List_Id := New_List;
70482933
RK		 3663 Equiv_Type : Entity_Id;
3664 Range_Type : Entity_Id;
3665 Str_Type : Entity_Id;
70482933
RK		 3666 Constr_Root : Entity_Id;
3667 Sizexpr : Node_Id;
3668
3669 begin
3670 if not Has_Discriminants (Root_Typ) then
3671 Constr_Root := Root_Typ;
3672 else
3673 Constr_Root :=
3674 Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
3675
3676 -- subtype cstr__n is T (List of discr constraints taken from Exp)
3677
3678 Append_To (List_Def,
3679 Make_Subtype_Declaration (Loc,
3680 Defining_Identifier => Constr_Root,
3681 Subtype_Indication =>
3682 Make_Subtype_From_Expr (E, Root_Typ)));
3683 end if;
3684
0712790c 3685 -- Generate the range subtype declaration
70482933
RK		 3686
3687 Range_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('G'));
3688
0712790c
ES		 3689 if not Is_Interface (Root_Typ) then
3690 -- subtype rg__xx is
3691 -- Storage_Offset range 1 .. (Expr'size - typ'size) / Storage_Unit
3692
3693 Sizexpr :=
3694 Make_Op_Subtract (Loc,
3695 Left_Opnd =>
3696 Make_Attribute_Reference (Loc,
3697 Prefix =>
3698 OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)),
3699 Attribute_Name => Name_Size),
3700 Right_Opnd =>
3701 Make_Attribute_Reference (Loc,
3702 Prefix => New_Reference_To (Constr_Root, Loc),
3703 Attribute_Name => Name_Object_Size));
3704 else
3705 -- subtype rg__xx is
3706 -- Storage_Offset range 1 .. Expr'size / Storage_Unit
3707
3708 Sizexpr :=
3709 Make_Attribute_Reference (Loc,
3710 Prefix =>
3711 OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)),
3712 Attribute_Name => Name_Size);
3713 end if;
70482933
RK		 3714
3715 Set_Paren_Count (Sizexpr, 1);
3716
3717 Append_To (List_Def,
3718 Make_Subtype_Declaration (Loc,
3719 Defining_Identifier => Range_Type,
3720 Subtype_Indication =>
3721 Make_Subtype_Indication (Loc,
3722 Subtype_Mark => New_Reference_To (RTE (RE_Storage_Offset), Loc),
3723 Constraint => Make_Range_Constraint (Loc,
3724 Range_Expression =>
3725 Make_Range (Loc,
3726 Low_Bound => Make_Integer_Literal (Loc, 1),
3727 High_Bound =>
3728 Make_Op_Divide (Loc,
3729 Left_Opnd => Sizexpr,
3730 Right_Opnd => Make_Integer_Literal (Loc,
3731 Intval => System_Storage_Unit)))))));
3732
3733 -- subtype str__nn is Storage_Array (rg__x);
3734
3735 Str_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
3736 Append_To (List_Def,
3737 Make_Subtype_Declaration (Loc,
3738 Defining_Identifier => Str_Type,
3739 Subtype_Indication =>
3740 Make_Subtype_Indication (Loc,
3741 Subtype_Mark => New_Reference_To (RTE (RE_Storage_Array), Loc),
3742 Constraint =>
3743 Make_Index_Or_Discriminant_Constraint (Loc,
3744 Constraints =>
3745 New_List (New_Reference_To (Range_Type, Loc))))));
3746
3747 -- type Equiv_T is record
0712790c 3748 -- [ _parent : Tnn; ]
70482933
RK		 3749 -- E : Str_Type;
3750 -- end Equiv_T;
3751
3752 Equiv_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
3753
fbf5a39b
AC		 3754 -- When the target requires front-end layout, it's necessary to allow
3755 -- the equivalent type to be frozen so that layout can occur (when the
3756 -- associated class-wide subtype is frozen, the equivalent type will
3757 -- be frozen, see freeze.adb). For other targets, Gigi wants to have
3758 -- the equivalent type marked as frozen and deals with this type itself.
3759 -- In the Gigi case this will also avoid the generation of an init
3760 -- procedure for the type.
70482933 3761
fbf5a39b
AC		 3762 if not Frontend_Layout_On_Target then
3763 Set_Is_Frozen (Equiv_Type);
3764 end if;
70482933
RK		 3765
3766 Set_Ekind (Equiv_Type, E_Record_Type);
3767 Set_Parent_Subtype (Equiv_Type, Constr_Root);
3768
0712790c
ES		 3769 if not Is_Interface (Root_Typ) then
3770 Append_To (Comp_List,
3771 Make_Component_Declaration (Loc,
3772 Defining_Identifier =>
3773 Make_Defining_Identifier (Loc, Name_uParent),
3774 Component_Definition =>
3775 Make_Component_Definition (Loc,
3776 Aliased_Present => False,
3777 Subtype_Indication => New_Reference_To (Constr_Root, Loc))));
3778 end if;
3779
3780 Append_To (Comp_List,
3781 Make_Component_Declaration (Loc,
3782 Defining_Identifier =>
3783 Make_Defining_Identifier (Loc,
3784 Chars => New_Internal_Name ('C')),
3785 Component_Definition =>
3786 Make_Component_Definition (Loc,
3787 Aliased_Present => False,
3788 Subtype_Indication => New_Reference_To (Str_Type, Loc))));
3789
70482933
RK		 3790 Append_To (List_Def,
3791 Make_Full_Type_Declaration (Loc,
3792 Defining_Identifier => Equiv_Type,
70482933
RK		 3793 Type_Definition =>
3794 Make_Record_Definition (Loc,
0712790c
ES		 3795 Component_List =>
3796 Make_Component_List (Loc,
3797 Component_Items => Comp_List,
3798 Variant_Part => Empty))));
3799
3800 -- Suppress all checks during the analysis of the expanded code
3801 -- to avoid the generation of spurious warnings under ZFP run-time.
3802
3803 Insert_Actions (E, List_Def, Suppress => All_Checks);
70482933
RK		 3804 return Equiv_Type;
3805 end Make_CW_Equivalent_Type;
3806
3807 ------------------------
3808 -- Make_Literal_Range --
3809 ------------------------
3810
3811 function Make_Literal_Range
3812 (Loc : Source_Ptr;
bebbff91 3813 Literal_Typ : Entity_Id) return Node_Id
70482933 3814 is
86cde7b1
RD		 3815 Lo : constant Node_Id :=
3816 New_Copy_Tree (String_Literal_Low_Bound (Literal_Typ));
3817 Index : constant Entity_Id := Etype (Lo);
3818
3819 Hi : Node_Id;
3820 Length_Expr : constant Node_Id :=
3821 Make_Op_Subtract (Loc,
3822 Left_Opnd =>
3823 Make_Integer_Literal (Loc,
3824 Intval => String_Literal_Length (Literal_Typ)),
3825 Right_Opnd =>
3826 Make_Integer_Literal (Loc, 1));
f91b40db 3827
70482933 3828 begin
f91b40db
GB		 3829 Set_Analyzed (Lo, False);
3830
86cde7b1
RD		 3831 if Is_Integer_Type (Index) then
3832 Hi :=
3833 Make_Op_Add (Loc,
3834 Left_Opnd => New_Copy_Tree (Lo),
3835 Right_Opnd => Length_Expr);
3836 else
3837 Hi :=
3838 Make_Attribute_Reference (Loc,
3839 Attribute_Name => Name_Val,
3840 Prefix => New_Occurrence_Of (Index, Loc),
3841 Expressions => New_List (
3842 Make_Op_Add (Loc,
3843 Left_Opnd =>
3844 Make_Attribute_Reference (Loc,
3845 Attribute_Name => Name_Pos,
3846 Prefix => New_Occurrence_Of (Index, Loc),
3847 Expressions => New_List (New_Copy_Tree (Lo))),
3848 Right_Opnd => Length_Expr)));
3849 end if;
3850
70482933
RK		 3851 return
3852 Make_Range (Loc,
86cde7b1
RD		 3853 Low_Bound => Lo,
3854 High_Bound => Hi);
70482933
RK		 3855 end Make_Literal_Range;
3856
3857 ----------------------------
3858 -- Make_Subtype_From_Expr --
3859 ----------------------------
3860
3861 -- 1. If Expr is an uncontrained array expression, creates
3862 -- Unc_Type(Expr'first(1)..Expr'Last(1),..., Expr'first(n)..Expr'last(n))
3863
3864 -- 2. If Expr is a unconstrained discriminated type expression, creates
3865 -- Unc_Type(Expr.Discr1, ... , Expr.Discr_n)
3866
3867 -- 3. If Expr is class-wide, creates an implicit class wide subtype
3868
3869 function Make_Subtype_From_Expr
3870 (E : Node_Id;
bebbff91 3871 Unc_Typ : Entity_Id) return Node_Id
70482933
RK		 3872 is
3873 Loc : constant Source_Ptr := Sloc (E);
fbf5a39b 3874 List_Constr : constant List_Id := New_List;
70482933
RK		 3875 D : Entity_Id;
3876
3877 Full_Subtyp : Entity_Id;
3878 Priv_Subtyp : Entity_Id;
3879 Utyp : Entity_Id;
3880 Full_Exp : Node_Id;
3881
3882 begin
3883 if Is_Private_Type (Unc_Typ)
3884 and then Has_Unknown_Discriminants (Unc_Typ)
3885 then
fbf5a39b 3886 -- Prepare the subtype completion, Go to base type to
ea985d95
RD		 3887 -- find underlying type, because the type may be a generic
3888 -- actual or an explicit subtype.
70482933 3889
fbf5a39b 3890 Utyp := Underlying_Type (Base_Type (Unc_Typ));
70482933
RK		 3891 Full_Subtyp := Make_Defining_Identifier (Loc,
3892 New_Internal_Name ('C'));
8cbb664e
MG		 3893 Full_Exp :=
3894 Unchecked_Convert_To
3895 (Utyp, Duplicate_Subexpr_No_Checks (E));
70482933
RK		 3896 Set_Parent (Full_Exp, Parent (E));
3897
3898 Priv_Subtyp :=
3899 Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
3900
3901 Insert_Action (E,
3902 Make_Subtype_Declaration (Loc,
3903 Defining_Identifier => Full_Subtyp,
3904 Subtype_Indication => Make_Subtype_From_Expr (Full_Exp, Utyp)));
3905
3906 -- Define the dummy private subtype
3907
3908 Set_Ekind (Priv_Subtyp, Subtype_Kind (Ekind (Unc_Typ)));
ea985d95 3909 Set_Etype (Priv_Subtyp, Base_Type (Unc_Typ));
70482933
RK		 3910 Set_Scope (Priv_Subtyp, Full_Subtyp);
3911 Set_Is_Constrained (Priv_Subtyp);
3912 Set_Is_Tagged_Type (Priv_Subtyp, Is_Tagged_Type (Unc_Typ));
3913 Set_Is_Itype (Priv_Subtyp);
3914 Set_Associated_Node_For_Itype (Priv_Subtyp, E);
3915
3916 if Is_Tagged_Type (Priv_Subtyp) then
3917 Set_Class_Wide_Type
3918 (Base_Type (Priv_Subtyp), Class_Wide_Type (Unc_Typ));
3919 Set_Primitive_Operations (Priv_Subtyp,
3920 Primitive_Operations (Unc_Typ));
3921 end if;
3922
3923 Set_Full_View (Priv_Subtyp, Full_Subtyp);
3924
3925 return New_Reference_To (Priv_Subtyp, Loc);
3926
3927 elsif Is_Array_Type (Unc_Typ) then
3928 for J in 1 .. Number_Dimensions (Unc_Typ) loop
3929 Append_To (List_Constr,
3930 Make_Range (Loc,
3931 Low_Bound =>
3932 Make_Attribute_Reference (Loc,
8cbb664e 3933 Prefix => Duplicate_Subexpr_No_Checks (E),
70482933
RK		 3934 Attribute_Name => Name_First,
3935 Expressions => New_List (
3936 Make_Integer_Literal (Loc, J))),
8cbb664e 3937
70482933
RK		 3938 High_Bound =>
3939 Make_Attribute_Reference (Loc,
8cbb664e 3940 Prefix => Duplicate_Subexpr_No_Checks (E),
70482933
RK		 3941 Attribute_Name => Name_Last,
3942 Expressions => New_List (
3943 Make_Integer_Literal (Loc, J)))));
3944 end loop;
3945
3946 elsif Is_Class_Wide_Type (Unc_Typ) then
3947 declare
3948 CW_Subtype : Entity_Id;
3949 EQ_Typ : Entity_Id := Empty;
3950
3951 begin
0712790c
ES		 3952 -- A class-wide equivalent type is not needed when VM_Target
3953 -- because the VM back-ends handle the class-wide object
44d6a706 3954 -- initialization itself (and doesn't need or want the
70482933
RK		 3955 -- additional intermediate type to handle the assignment).
3956
0712790c 3957 if Expander_Active and then VM_Target = No_VM then
70482933
RK		 3958 EQ_Typ := Make_CW_Equivalent_Type (Unc_Typ, E);
3959 end if;
3960
3961 CW_Subtype := New_Class_Wide_Subtype (Unc_Typ, E);
3962 Set_Equivalent_Type (CW_Subtype, EQ_Typ);
fbf5a39b
AC		 3963
3964 if Present (EQ_Typ) then
3965 Set_Is_Class_Wide_Equivalent_Type (EQ_Typ);
3966 end if;
3967
70482933
RK		 3968 Set_Cloned_Subtype (CW_Subtype, Base_Type (Unc_Typ));
3969
3970 return New_Occurrence_Of (CW_Subtype, Loc);
3971 end;
3972
ea985d95 3973 -- Indefinite record type with discriminants
fbf5a39b 3974
70482933
RK		 3975 else
3976 D := First_Discriminant (Unc_Typ);
fbf5a39b 3977 while Present (D) loop
70482933
RK		 3978 Append_To (List_Constr,
3979 Make_Selected_Component (Loc,
8cbb664e 3980 Prefix => Duplicate_Subexpr_No_Checks (E),
70482933
RK		 3981 Selector_Name => New_Reference_To (D, Loc)));
3982
3983 Next_Discriminant (D);
3984 end loop;
3985 end if;
3986
3987 return
3988 Make_Subtype_Indication (Loc,
3989 Subtype_Mark => New_Reference_To (Unc_Typ, Loc),
3990 Constraint =>
3991 Make_Index_Or_Discriminant_Constraint (Loc,
3992 Constraints => List_Constr));
3993 end Make_Subtype_From_Expr;
3994
3995 -----------------------------
3996 -- May_Generate_Large_Temp --
3997 -----------------------------
3998
3999 -- At the current time, the only types that we return False for (i.e.
4000 -- where we decide we know they cannot generate large temps) are ones
8adcacef 4001 -- where we know the size is 256 bits or less at compile time, and we
70482933
RK		 4002 -- are still not doing a thorough job on arrays and records ???
4003
4004 function May_Generate_Large_Temp (Typ : Entity_Id) return Boolean is
4005 begin
7324bf49 4006 if not Size_Known_At_Compile_Time (Typ) then
70482933
RK		 4007 return False;
4008
4009 elsif Esize (Typ) /= 0 and then Esize (Typ) <= 256 then
4010 return False;
4011
4012 elsif Is_Array_Type (Typ)
4013 and then Present (Packed_Array_Type (Typ))
4014 then
4015 return May_Generate_Large_Temp (Packed_Array_Type (Typ));
4016
4017 -- We could do more here to find other small types ???
4018
4019 else
4020 return True;
4021 end if;
4022 end May_Generate_Large_Temp;
4023
70482933
RK		 4024 ----------------------------
4025 -- New_Class_Wide_Subtype --
4026 ----------------------------
4027
4028 function New_Class_Wide_Subtype
4029 (CW_Typ : Entity_Id;
bebbff91 4030 N : Node_Id) return Entity_Id
70482933 4031 is
fbf5a39b
AC		 4032 Res : constant Entity_Id := Create_Itype (E_Void, N);
4033 Res_Name : constant Name_Id := Chars (Res);
4034 Res_Scope : constant Entity_Id := Scope (Res);
70482933
RK		 4035
4036 begin
4037 Copy_Node (CW_Typ, Res);
05350ac6 4038 Set_Comes_From_Source (Res, False);
70482933
RK		 4039 Set_Sloc (Res, Sloc (N));
4040 Set_Is_Itype (Res);
4041 Set_Associated_Node_For_Itype (Res, N);
4042 Set_Is_Public (Res, False); -- By default, may be changed below.
4043 Set_Public_Status (Res);
4044 Set_Chars (Res, Res_Name);
4045 Set_Scope (Res, Res_Scope);
4046 Set_Ekind (Res, E_Class_Wide_Subtype);
4047 Set_Next_Entity (Res, Empty);
4048 Set_Etype (Res, Base_Type (CW_Typ));
fbf5a39b
AC		 4049
4050 -- For targets where front-end layout is required, reset the Is_Frozen
4051 -- status of the subtype to False (it can be implicitly set to true
4052 -- from the copy of the class-wide type). For other targets, Gigi
4053 -- doesn't want the class-wide subtype to go through the freezing
4054 -- process (though it's unclear why that causes problems and it would
4055 -- be nice to allow freezing to occur normally for all targets ???).
4056
4057 if Frontend_Layout_On_Target then
4058 Set_Is_Frozen (Res, False);
4059 end if;
4060
70482933
RK		 4061 Set_Freeze_Node (Res, Empty);
4062 return (Res);
4063 end New_Class_Wide_Subtype;
4064
0712790c
ES		 4065 --------------------------------
4066 -- Non_Limited_Designated_Type --
4067 ---------------------------------
4068
4069 function Non_Limited_Designated_Type (T : Entity_Id) return Entity_Id is
4070 Desig : constant Entity_Id := Designated_Type (T);
4071 begin
4072 if Ekind (Desig) = E_Incomplete_Type
4073 and then Present (Non_Limited_View (Desig))
4074 then
4075 return Non_Limited_View (Desig);
4076 else
4077 return Desig;
4078 end if;
4079 end Non_Limited_Designated_Type;
4080
59e54267
ES		 4081 -----------------------------------
4082 -- OK_To_Do_Constant_Replacement --
4083 -----------------------------------
4084
4085 function OK_To_Do_Constant_Replacement (E : Entity_Id) return Boolean is
4086 ES : constant Entity_Id := Scope (E);
4087 CS : Entity_Id;
4088
4089 begin
4090 -- Do not replace statically allocated objects, because they may be
4091 -- modified outside the current scope.
4092
4093 if Is_Statically_Allocated (E) then
4094 return False;
4095
4096 -- Do not replace aliased or volatile objects, since we don't know what
4097 -- else might change the value.
4098
4099 elsif Is_Aliased (E) or else Treat_As_Volatile (E) then
4100 return False;
4101
4102 -- Debug flag -gnatdM disconnects this optimization
4103
4104 elsif Debug_Flag_MM then
4105 return False;
4106
4107 -- Otherwise check scopes
4108
4109 else
59e54267
ES		 4110 CS := Current_Scope;
4111
4112 loop
4113 -- If we are in right scope, replacement is safe
4114
4115 if CS = ES then
4116 return True;
4117
4118 -- Packages do not affect the determination of safety
4119
4120 elsif Ekind (CS) = E_Package then
59e54267 4121 exit when CS = Standard_Standard;
05350ac6 4122 CS := Scope (CS);
59e54267
ES		 4123
4124 -- Blocks do not affect the determination of safety
4125
4126 elsif Ekind (CS) = E_Block then
4127 CS := Scope (CS);
4128
05350ac6
BD		 4129 -- Loops do not affect the determination of safety. Note that we
4130 -- kill all current values on entry to a loop, so we are just
4131 -- talking about processing within a loop here.
4132
4133 elsif Ekind (CS) = E_Loop then
4134 CS := Scope (CS);
4135
59e54267
ES		 4136 -- Otherwise, the reference is dubious, and we cannot be sure that
4137 -- it is safe to do the replacement.
4138
4139 else
4140 exit;
4141 end if;
4142 end loop;
4143
4144 return False;
4145 end if;
4146 end OK_To_Do_Constant_Replacement;
4147
0712790c
ES		 4148 ------------------------------------
4149 -- Possible_Bit_Aligned_Component --
4150 ------------------------------------
4151
4152 function Possible_Bit_Aligned_Component (N : Node_Id) return Boolean is
4153 begin
4154 case Nkind (N) is
4155
4156 -- Case of indexed component
4157
4158 when N_Indexed_Component =>
4159 declare
4160 P : constant Node_Id := Prefix (N);
4161 Ptyp : constant Entity_Id := Etype (P);
4162
4163 begin
4164 -- If we know the component size and it is less than 64, then
4165 -- we are definitely OK. The back end always does assignment
4166 -- of misaligned small objects correctly.
4167
4168 if Known_Static_Component_Size (Ptyp)
4169 and then Component_Size (Ptyp) <= 64
4170 then
4171 return False;
4172
4173 -- Otherwise, we need to test the prefix, to see if we are
4174 -- indexing from a possibly unaligned component.
4175
4176 else
4177 return Possible_Bit_Aligned_Component (P);
4178 end if;
4179 end;
4180
4181 -- Case of selected component
4182
4183 when N_Selected_Component =>
4184 declare
4185 P : constant Node_Id := Prefix (N);
4186 Comp : constant Entity_Id := Entity (Selector_Name (N));
4187
4188 begin
4189 -- If there is no component clause, then we are in the clear
4190 -- since the back end will never misalign a large component
4191 -- unless it is forced to do so. In the clear means we need
4192 -- only the recursive test on the prefix.
4193
4194 if Component_May_Be_Bit_Aligned (Comp) then
4195 return True;
4196 else
4197 return Possible_Bit_Aligned_Component (P);
4198 end if;
4199 end;
4200
4201 -- If we have neither a record nor array component, it means that we
4202 -- have fallen off the top testing prefixes recursively, and we now
4203 -- have a stand alone object, where we don't have a problem.
4204
4205 when others =>
4206 return False;
4207
4208 end case;
4209 end Possible_Bit_Aligned_Component;
4210
70482933
RK		 4211 -------------------------
4212 -- Remove_Side_Effects --
4213 -------------------------
4214
4215 procedure Remove_Side_Effects
4216 (Exp : Node_Id;
4217 Name_Req : Boolean := False;
4218 Variable_Ref : Boolean := False)
4219 is
59e54267 4220 Loc : constant Source_Ptr := Sloc (Exp);
fbf5a39b
AC		 4221 Exp_Type : constant Entity_Id := Etype (Exp);
4222 Svg_Suppress : constant Suppress_Array := Scope_Suppress;
70482933
RK		 4223 Def_Id : Entity_Id;
4224 Ref_Type : Entity_Id;
4225 Res : Node_Id;
4226 Ptr_Typ_Decl : Node_Id;
4227 New_Exp : Node_Id;
4228 E : Node_Id;
4229
4230 function Side_Effect_Free (N : Node_Id) return Boolean;
59e54267
ES		 4231 -- Determines if the tree N represents an expression that is known not
4232 -- to have side effects, and for which no processing is required.
70482933
RK		 4233
4234 function Side_Effect_Free (L : List_Id) return Boolean;
4235 -- Determines if all elements of the list L are side effect free
4236
fbf5a39b 4237 function Safe_Prefixed_Reference (N : Node_Id) return Boolean;
59e54267
ES		 4238 -- The argument N is a construct where the Prefix is dereferenced if it
4239 -- is an access type and the result is a variable. The call returns True
4240 -- if the construct is side effect free (not considering side effects in
4241 -- other than the prefix which are to be tested by the caller).
fbf5a39b
AC		 4242
4243 function Within_In_Parameter (N : Node_Id) return Boolean;
59e54267
ES		 4244 -- Determines if N is a subcomponent of a composite in-parameter. If so,
4245 -- N is not side-effect free when the actual is global and modifiable
4246 -- indirectly from within a subprogram, because it may be passed by
4247 -- reference. The front-end must be conservative here and assume that
4248 -- this may happen with any array or record type. On the other hand, we
4249 -- cannot create temporaries for all expressions for which this
4250 -- condition is true, for various reasons that might require clearing up
4251 -- ??? For example, descriminant references that appear out of place, or
4252 -- spurious type errors with class-wide expressions. As a result, we
4253 -- limit the transformation to loop bounds, which is so far the only
4254 -- case that requires it.
fbf5a39b
AC		 4255
4256 -----------------------------
4257 -- Safe_Prefixed_Reference --
4258 -----------------------------
4259
4260 function Safe_Prefixed_Reference (N : Node_Id) return Boolean is
4261 begin
4262 -- If prefix is not side effect free, definitely not safe
70482933 4263
fbf5a39b
AC		 4264 if not Side_Effect_Free (Prefix (N)) then
4265 return False;
70482933 4266
fbf5a39b
AC		 4267 -- If the prefix is of an access type that is not access-to-constant,
4268 -- then this construct is a variable reference, which means it is to
4269 -- be considered to have side effects if Variable_Ref is set True
4270 -- Exception is an access to an entity that is a constant or an
4271 -- in-parameter which does not come from source, and is the result
4272 -- of a previous removal of side-effects.
4273
4274 elsif Is_Access_Type (Etype (Prefix (N)))
70482933 4275 and then not Is_Access_Constant (Etype (Prefix (N)))
fbf5a39b
AC		 4276 and then Variable_Ref
4277 then
4278 if not Is_Entity_Name (Prefix (N)) then
4279 return False;
4280 else
4281 return Ekind (Entity (Prefix (N))) = E_Constant
4282 or else Ekind (Entity (Prefix (N))) = E_In_Parameter;
4283 end if;
4284
4285 -- The following test is the simplest way of solving a complex
4286 -- problem uncovered by BB08-010: Side effect on loop bound that
4287 -- is a subcomponent of a global variable:
4288 -- If a loop bound is a subcomponent of a global variable, a
4289 -- modification of that variable within the loop may incorrectly
4290 -- affect the execution of the loop.
4291
4292 elsif not
4293 (Nkind (Parent (Parent (N))) /= N_Loop_Parameter_Specification
4294 or else not Within_In_Parameter (Prefix (N)))
4295 then
4296 return False;
4297
4298 -- All other cases are side effect free
4299
4300 else
4301 return True;
4302 end if;
4303 end Safe_Prefixed_Reference;
70482933
RK		 4304
4305 ----------------------
4306 -- Side_Effect_Free --
4307 ----------------------
4308
4309 function Side_Effect_Free (N : Node_Id) return Boolean is
70482933
RK		 4310 begin
4311 -- Note on checks that could raise Constraint_Error. Strictly, if
4312 -- we take advantage of 11.6, these checks do not count as side
4313 -- effects. However, we would just as soon consider that they are
4314 -- side effects, since the backend CSE does not work very well on
4315 -- expressions which can raise Constraint_Error. On the other
4316 -- hand, if we do not consider them to be side effect free, then
4317 -- we get some awkward expansions in -gnato mode, resulting in
4318 -- code insertions at a point where we do not have a clear model
4319 -- for performing the insertions. See 4908-002/comment for details.
4320
fbf5a39b 4321 -- Special handling for entity names
70482933 4322
fbf5a39b 4323 if Is_Entity_Name (N) then
70482933 4324
70482933
RK		 4325 -- If the entity is a constant, it is definitely side effect
4326 -- free. Note that the test of Is_Variable (N) below might
4327 -- be expected to catch this case, but it does not, because
4328 -- this test goes to the original tree, and we may have
4329 -- already rewritten a variable node with a constant as
4330 -- a result of an earlier Force_Evaluation call.
4331
fbf5a39b
AC		 4332 if Ekind (Entity (N)) = E_Constant
4333 or else Ekind (Entity (N)) = E_In_Parameter
4334 then
70482933
RK		 4335 return True;
4336
fbf5a39b
AC		 4337 -- Functions are not side effect free
4338
4339 elsif Ekind (Entity (N)) = E_Function then
4340 return False;
4341
4342 -- Variables are considered to be a side effect if Variable_Ref
4343 -- is set or if we have a volatile variable and Name_Req is off.
4344 -- If Name_Req is True then we can't help returning a name which
4345 -- effectively allows multiple references in any case.
70482933 4346
fbf5a39b
AC		 4347 elsif Is_Variable (N) then
4348 return not Variable_Ref
4349 and then (not Treat_As_Volatile (Entity (N))
4350 or else Name_Req);
4351
4352 -- Any other entity (e.g. a subtype name) is definitely side
4353 -- effect free.
70482933
RK		 4354
4355 else
4356 return True;
4357 end if;
4358
4359 -- A value known at compile time is always side effect free
4360
4361 elsif Compile_Time_Known_Value (N) then
4362 return True;
0712790c
ES		 4363
4364 -- A variable renaming is not side-effet free, because the
4365 -- renaming will function like a macro in the front-end in
4366 -- some cases, and an assignment can modify the the component
4367 -- designated by N, so we need to create a temporary for it.
4368
4369 elsif Is_Entity_Name (Original_Node (N))
4370 and then Is_Renaming_Of_Object (Entity (Original_Node (N)))
4371 and then Ekind (Entity (Original_Node (N))) /= E_Constant
4372 then
4373 return False;
fbf5a39b 4374 end if;
70482933 4375
fbf5a39b
AC		 4376 -- For other than entity names and compile time known values,
4377 -- check the node kind for special processing.
70482933 4378
fbf5a39b
AC		 4379 case Nkind (N) is
4380
4381 -- An attribute reference is side effect free if its expressions
4382 -- are side effect free and its prefix is side effect free or
4383 -- is an entity reference.
4384
4385 -- Is this right? what about x'first where x is a variable???
4386
4387 when N_Attribute_Reference =>
4388 return Side_Effect_Free (Expressions (N))
59e54267 4389 and then Attribute_Name (N) /= Name_Input
fbf5a39b
AC		 4390 and then (Is_Entity_Name (Prefix (N))
4391 or else Side_Effect_Free (Prefix (N)));
4392
4393 -- A binary operator is side effect free if and both operands
4394 -- are side effect free. For this purpose binary operators
4395 -- include membership tests and short circuit forms
4396
05350ac6
BD		 4397 when N_Binary_Op |
4398 N_Membership_Test |
4399 N_And_Then |
4400 N_Or_Else =>
fbf5a39b
AC		 4401 return Side_Effect_Free (Left_Opnd (N))
4402 and then Side_Effect_Free (Right_Opnd (N));
4403
4404 -- An explicit dereference is side effect free only if it is
4405 -- a side effect free prefixed reference.
4406
4407 when N_Explicit_Dereference =>
4408 return Safe_Prefixed_Reference (N);
4409
4410 -- A call to _rep_to_pos is side effect free, since we generate
4411 -- this pure function call ourselves. Moreover it is critically
4412 -- important to make this exception, since otherwise we can
4413 -- have discriminants in array components which don't look
4414 -- side effect free in the case of an array whose index type
4415 -- is an enumeration type with an enumeration rep clause.
4416
4417 -- All other function calls are not side effect free
4418
4419 when N_Function_Call =>
4420 return Nkind (Name (N)) = N_Identifier
4421 and then Is_TSS (Name (N), TSS_Rep_To_Pos)
4422 and then
4423 Side_Effect_Free (First (Parameter_Associations (N)));
70482933 4424
fbf5a39b
AC		 4425 -- An indexed component is side effect free if it is a side
4426 -- effect free prefixed reference and all the indexing
4427 -- expressions are side effect free.
70482933 4428
fbf5a39b
AC		 4429 when N_Indexed_Component =>
4430 return Side_Effect_Free (Expressions (N))
4431 and then Safe_Prefixed_Reference (N);
70482933 4432
fbf5a39b
AC		 4433 -- A type qualification is side effect free if the expression
4434 -- is side effect free.
70482933 4435
fbf5a39b 4436 when N_Qualified_Expression =>
70482933 4437 return Side_Effect_Free (Expression (N));
70482933 4438
fbf5a39b 4439 -- A selected component is side effect free only if it is a
86cde7b1
RD		 4440 -- side effect free prefixed reference. If it designates a
4441 -- component with a rep. clause it must be treated has having
4442 -- a potential side effect, because it may be modified through
4443 -- a renaming, and a subsequent use of the renaming as a macro
4444 -- will yield the wrong value. This complex interaction between
4445 -- renaming and removing side effects is a reminder that the
4446 -- latter has become a headache to maintain, and that it should
4447 -- be removed in favor of the gcc mechanism to capture values ???
70482933 4448
fbf5a39b 4449 when N_Selected_Component =>
86cde7b1
RD		 4450 if Nkind (Parent (N)) = N_Explicit_Dereference
4451 and then Has_Non_Standard_Rep (Designated_Type (Etype (N)))
4452 then
4453 return False;
4454 else
4455 return Safe_Prefixed_Reference (N);
4456 end if;
70482933 4457
fbf5a39b 4458 -- A range is side effect free if the bounds are side effect free
70482933 4459
fbf5a39b
AC		 4460 when N_Range =>
4461 return Side_Effect_Free (Low_Bound (N))
4462 and then Side_Effect_Free (High_Bound (N));
70482933 4463
fbf5a39b
AC		 4464 -- A slice is side effect free if it is a side effect free
4465 -- prefixed reference and the bounds are side effect free.
70482933 4466
fbf5a39b
AC		 4467 when N_Slice =>
4468 return Side_Effect_Free (Discrete_Range (N))
4469 and then Safe_Prefixed_Reference (N);
70482933 4470
86cde7b1
RD		 4471 -- A type conversion is side effect free if the expression to be
4472 -- converted is side effect free.
70482933 4473
fbf5a39b
AC		 4474 when N_Type_Conversion =>
4475 return Side_Effect_Free (Expression (N));
4476
4477 -- A unary operator is side effect free if the operand
4478 -- is side effect free.
4479
4480 when N_Unary_Op =>
4481 return Side_Effect_Free (Right_Opnd (N));
4482
4483 -- An unchecked type conversion is side effect free only if it
4484 -- is safe and its argument is side effect free.
4485
4486 when N_Unchecked_Type_Conversion =>
4487 return Safe_Unchecked_Type_Conversion (N)
4488 and then Side_Effect_Free (Expression (N));
4489
4490 -- An unchecked expression is side effect free if its expression
4491 -- is side effect free.
4492
4493 when N_Unchecked_Expression =>
4494 return Side_Effect_Free (Expression (N));
4495
5c1c8a03
AC		 4496 -- A literal is side effect free
4497
4498 when N_Character_Literal |
4499 N_Integer_Literal |
4500 N_Real_Literal |
6e059adb 4501 N_String_Literal =>
5c1c8a03
AC		 4502 return True;
4503
fbf5a39b
AC		 4504 -- We consider that anything else has side effects. This is a bit
4505 -- crude, but we are pretty close for most common cases, and we
4506 -- are certainly correct (i.e. we never return True when the
4507 -- answer should be False).
4508
4509 when others =>
4510 return False;
4511 end case;
70482933
RK		 4512 end Side_Effect_Free;
4513
fbf5a39b
AC		 4514 -- A list is side effect free if all elements of the list are
4515 -- side effect free.
4516
70482933
RK		 4517 function Side_Effect_Free (L : List_Id) return Boolean is
4518 N : Node_Id;
4519
4520 begin
4521 if L = No_List or else L = Error_List then
4522 return True;
4523
4524 else
4525 N := First (L);
70482933
RK		 4526 while Present (N) loop
4527 if not Side_Effect_Free (N) then
4528 return False;
4529 else
4530 Next (N);
4531 end if;
4532 end loop;
4533
4534 return True;
4535 end if;
4536 end Side_Effect_Free;
4537
fbf5a39b
AC		 4538 -------------------------
4539 -- Within_In_Parameter --
4540 -------------------------
4541
4542 function Within_In_Parameter (N : Node_Id) return Boolean is
4543 begin
4544 if not Comes_From_Source (N) then
4545 return False;
4546
4547 elsif Is_Entity_Name (N) then
86cde7b1 4548 return Ekind (Entity (N)) = E_In_Parameter;
fbf5a39b
AC		 4549
4550 elsif Nkind (N) = N_Indexed_Component
4551 or else Nkind (N) = N_Selected_Component
4552 then
4553 return Within_In_Parameter (Prefix (N));
4554 else
4555
4556 return False;
4557 end if;
4558 end Within_In_Parameter;
4559
70482933
RK		 4560 -- Start of processing for Remove_Side_Effects
4561
4562 begin
4563 -- If we are side effect free already or expansion is disabled,
4564 -- there is nothing to do.
4565
4566 if Side_Effect_Free (Exp) or else not Expander_Active then
4567 return;
4568 end if;
4569
fbf5a39b 4570 -- All this must not have any checks
70482933
RK		 4571
4572 Scope_Suppress := (others => True);
4573
86cde7b1
RD		 4574 -- If it is a scalar type and we need to capture the value, just make
4575 -- a copy. Likewise for a function or operator call. And if we have a
4576 -- volatile variable and Nam_Req is not set (see comments above for
4577 -- Side_Effect_Free).
d9e0a587
EB		 4578
4579 if Is_Elementary_Type (Exp_Type)
4580 and then (Variable_Ref
4581 or else Nkind (Exp) = N_Function_Call
86cde7b1 4582 or else Nkind (Exp) in N_Op
d9e0a587
EB		 4583 or else (not Name_Req
4584 and then Is_Entity_Name (Exp)
4585 and then Treat_As_Volatile (Entity (Exp))))
4586 then
d9e0a587
EB		 4587 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4588 Set_Etype (Def_Id, Exp_Type);
4589 Res := New_Reference_To (Def_Id, Loc);
4590
4591 E :=
4592 Make_Object_Declaration (Loc,
4593 Defining_Identifier => Def_Id,
4594 Object_Definition => New_Reference_To (Exp_Type, Loc),
4595 Constant_Present => True,
4596 Expression => Relocate_Node (Exp));
4597
4598 Set_Assignment_OK (E);
4599 Insert_Action (Exp, E);
4600
70482933
RK		 4601 -- If the expression has the form v.all then we can just capture
4602 -- the pointer, and then do an explicit dereference on the result.
4603
d9e0a587 4604 elsif Nkind (Exp) = N_Explicit_Dereference then
70482933
RK		 4605 Def_Id :=
4606 Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4607 Res :=
4608 Make_Explicit_Dereference (Loc, New_Reference_To (Def_Id, Loc));
4609
4610 Insert_Action (Exp,
4611 Make_Object_Declaration (Loc,
4612 Defining_Identifier => Def_Id,
4613 Object_Definition =>
4614 New_Reference_To (Etype (Prefix (Exp)), Loc),
4615 Constant_Present => True,
4616 Expression => Relocate_Node (Prefix (Exp))));
4617
fbf5a39b
AC		 4618 -- Similar processing for an unchecked conversion of an expression
4619 -- of the form v.all, where we want the same kind of treatment.
4620
4621 elsif Nkind (Exp) = N_Unchecked_Type_Conversion
4622 and then Nkind (Expression (Exp)) = N_Explicit_Dereference
4623 then
8adcacef 4624 Remove_Side_Effects (Expression (Exp), Name_Req, Variable_Ref);
fbf5a39b
AC		 4625 Scope_Suppress := Svg_Suppress;
4626 return;
4627
70482933
RK		 4628 -- If this is a type conversion, leave the type conversion and remove
4629 -- the side effects in the expression. This is important in several
4630 -- circumstances: for change of representations, and also when this
4631 -- is a view conversion to a smaller object, where gigi can end up
8adcacef 4632 -- creating its own temporary of the wrong size.
c9a4817d 4633
59e54267 4634 elsif Nkind (Exp) = N_Type_Conversion then
8adcacef 4635 Remove_Side_Effects (Expression (Exp), Name_Req, Variable_Ref);
70482933
RK		 4636 Scope_Suppress := Svg_Suppress;
4637 return;
4638
d9e0a587
EB		 4639 -- If this is an unchecked conversion that Gigi can't handle, make
4640 -- a copy or a use a renaming to capture the value.
4641
4642 elsif Nkind (Exp) = N_Unchecked_Type_Conversion
4643 and then not Safe_Unchecked_Type_Conversion (Exp)
4644 then
dee4682a 4645 if CW_Or_Controlled_Type (Exp_Type) then
d9e0a587
EB		 4646
4647 -- Use a renaming to capture the expression, rather than create
4648 -- a controlled temporary.
4649
4650 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4651 Res := New_Reference_To (Def_Id, Loc);
4652
4653 Insert_Action (Exp,
4654 Make_Object_Renaming_Declaration (Loc,
4655 Defining_Identifier => Def_Id,
4656 Subtype_Mark => New_Reference_To (Exp_Type, Loc),
4657 Name => Relocate_Node (Exp)));
4658
4659 else
4660 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4661 Set_Etype (Def_Id, Exp_Type);
4662 Res := New_Reference_To (Def_Id, Loc);
4663
4664 E :=
4665 Make_Object_Declaration (Loc,
4666 Defining_Identifier => Def_Id,
4667 Object_Definition => New_Reference_To (Exp_Type, Loc),
4668 Constant_Present => not Is_Variable (Exp),
4669 Expression => Relocate_Node (Exp));
4670
4671 Set_Assignment_OK (E);
4672 Insert_Action (Exp, E);
4673 end if;
4674
70482933
RK		 4675 -- For expressions that denote objects, we can use a renaming scheme.
4676 -- We skip using this if we have a volatile variable and we do not
4677 -- have Nam_Req set true (see comments above for Side_Effect_Free).
fbf5a39b 4678
70482933
RK		 4679 elsif Is_Object_Reference (Exp)
4680 and then Nkind (Exp) /= N_Function_Call
70482933
RK		 4681 and then (Name_Req
4682 or else not Is_Entity_Name (Exp)
fbf5a39b 4683 or else not Treat_As_Volatile (Entity (Exp)))
70482933
RK		 4684 then
4685 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4686
4687 if Nkind (Exp) = N_Selected_Component
4688 and then Nkind (Prefix (Exp)) = N_Function_Call
59e54267 4689 and then Is_Array_Type (Exp_Type)
70482933
RK		 4690 then
4691 -- Avoid generating a variable-sized temporary, by generating
4692 -- the renaming declaration just for the function call. The
4693 -- transformation could be refined to apply only when the array
4694 -- component is constrained by a discriminant???
4695
4696 Res :=
4697 Make_Selected_Component (Loc,
4698 Prefix => New_Occurrence_Of (Def_Id, Loc),
4699 Selector_Name => Selector_Name (Exp));
4700
4701 Insert_Action (Exp,
4702 Make_Object_Renaming_Declaration (Loc,
4703 Defining_Identifier => Def_Id,
4704 Subtype_Mark =>
4705 New_Reference_To (Base_Type (Etype (Prefix (Exp))), Loc),
4706 Name => Relocate_Node (Prefix (Exp))));
fbf5a39b 4707
70482933
RK		 4708 else
4709 Res := New_Reference_To (Def_Id, Loc);
4710
4711 Insert_Action (Exp,
4712 Make_Object_Renaming_Declaration (Loc,
4713 Defining_Identifier => Def_Id,
4714 Subtype_Mark => New_Reference_To (Exp_Type, Loc),
4715 Name => Relocate_Node (Exp)));
fbf5a39b 4716
70482933
RK		 4717 end if;
4718
59e54267
ES		 4719 -- If this is a packed reference, or a selected component with a
4720 -- non-standard representation, a reference to the temporary will
4721 -- be replaced by a copy of the original expression (see
4722 -- exp_ch2.Expand_Renaming). Otherwise the temporary must be
4723 -- elaborated by gigi, and is of course not to be replaced in-line
4724 -- by the expression it renames, which would defeat the purpose of
4725 -- removing the side-effect.
4726
4727 if (Nkind (Exp) = N_Selected_Component
4728 or else Nkind (Exp) = N_Indexed_Component)
4729 and then Has_Non_Standard_Rep (Etype (Prefix (Exp)))
4730 then
4731 null;
4732 else
4733 Set_Is_Renaming_Of_Object (Def_Id, False);
4734 end if;
70482933
RK		 4735
4736 -- Otherwise we generate a reference to the value
4737
4738 else
4739 Ref_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
4740
4741 Ptr_Typ_Decl :=
4742 Make_Full_Type_Declaration (Loc,
4743 Defining_Identifier => Ref_Type,
4744 Type_Definition =>
4745 Make_Access_To_Object_Definition (Loc,
4746 All_Present => True,
4747 Subtype_Indication =>
4748 New_Reference_To (Exp_Type, Loc)));
4749
4750 E := Exp;
4751 Insert_Action (Exp, Ptr_Typ_Decl);
4752
4753 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4754 Set_Etype (Def_Id, Exp_Type);
4755
4756 Res :=
4757 Make_Explicit_Dereference (Loc,
4758 Prefix => New_Reference_To (Def_Id, Loc));
4759
4760 if Nkind (E) = N_Explicit_Dereference then
4761 New_Exp := Relocate_Node (Prefix (E));
4762 else
4763 E := Relocate_Node (E);
4764 New_Exp := Make_Reference (Loc, E);
4765 end if;
4766
f44fe430
RD		 4767 if Is_Delayed_Aggregate (E) then
4768
4769 -- The expansion of nested aggregates is delayed until the
4770 -- enclosing aggregate is expanded. As aggregates are often
4771 -- qualified, the predicate applies to qualified expressions
4772 -- as well, indicating that the enclosing aggregate has not
4773 -- been expanded yet. At this point the aggregate is part of
4774 -- a stand-alone declaration, and must be fully expanded.
4775
4776 if Nkind (E) = N_Qualified_Expression then
4777 Set_Expansion_Delayed (Expression (E), False);
4778 Set_Analyzed (Expression (E), False);
4779 else
4780 Set_Expansion_Delayed (E, False);
4781 end if;
4782
70482933
RK		 4783 Set_Analyzed (E, False);
4784 end if;
4785
4786 Insert_Action (Exp,
4787 Make_Object_Declaration (Loc,
4788 Defining_Identifier => Def_Id,
4789 Object_Definition => New_Reference_To (Ref_Type, Loc),
4790 Expression => New_Exp));
4791 end if;
4792
4793 -- Preserve the Assignment_OK flag in all copies, since at least
4794 -- one copy may be used in a context where this flag must be set
4795 -- (otherwise why would the flag be set in the first place).
4796
4797 Set_Assignment_OK (Res, Assignment_OK (Exp));
4798
4799 -- Finally rewrite the original expression and we are done
4800
4801 Rewrite (Exp, Res);
4802 Analyze_And_Resolve (Exp, Exp_Type);
4803 Scope_Suppress := Svg_Suppress;
4804 end Remove_Side_Effects;
4805
f44fe430
RD		 4806 ---------------------------
4807 -- Represented_As_Scalar --
4808 ---------------------------
4809
4810 function Represented_As_Scalar (T : Entity_Id) return Boolean is
4811 UT : constant Entity_Id := Underlying_Type (T);
4812 begin
4813 return Is_Scalar_Type (UT)
4814 or else (Is_Bit_Packed_Array (UT)
4815 and then Is_Scalar_Type (Packed_Array_Type (UT)));
4816 end Represented_As_Scalar;
4817
70482933
RK		 4818 ------------------------------------
4819 -- Safe_Unchecked_Type_Conversion --
4820 ------------------------------------
4821
4822 -- Note: this function knows quite a bit about the exact requirements
4823 -- of Gigi with respect to unchecked type conversions, and its code
4824 -- must be coordinated with any changes in Gigi in this area.
4825
4826 -- The above requirements should be documented in Sinfo ???
4827
4828 function Safe_Unchecked_Type_Conversion (Exp : Node_Id) return Boolean is
4829 Otyp : Entity_Id;
4830 Ityp : Entity_Id;
4831 Oalign : Uint;
4832 Ialign : Uint;
4833 Pexp : constant Node_Id := Parent (Exp);
4834
4835 begin
4836 -- If the expression is the RHS of an assignment or object declaration
4837 -- we are always OK because there will always be a target.
4838
4839 -- Object renaming declarations, (generated for view conversions of
4840 -- actuals in inlined calls), like object declarations, provide an
4841 -- explicit type, and are safe as well.
4842
4843 if (Nkind (Pexp) = N_Assignment_Statement
4844 and then Expression (Pexp) = Exp)
4845 or else Nkind (Pexp) = N_Object_Declaration
4846 or else Nkind (Pexp) = N_Object_Renaming_Declaration
4847 then
4848 return True;
4849
4850 -- If the expression is the prefix of an N_Selected_Component
4851 -- we should also be OK because GCC knows to look inside the
4852 -- conversion except if the type is discriminated. We assume
4853 -- that we are OK anyway if the type is not set yet or if it is
4854 -- controlled since we can't afford to introduce a temporary in
4855 -- this case.
4856
4857 elsif Nkind (Pexp) = N_Selected_Component
4858 and then Prefix (Pexp) = Exp
4859 then
4860 if No (Etype (Pexp)) then
4861 return True;
4862 else
4863 return
4864 not Has_Discriminants (Etype (Pexp))
4865 or else Is_Constrained (Etype (Pexp));
4866 end if;
4867 end if;
4868
4869 -- Set the output type, this comes from Etype if it is set, otherwise
4870 -- we take it from the subtype mark, which we assume was already
4871 -- fully analyzed.
4872
4873 if Present (Etype (Exp)) then
4874 Otyp := Etype (Exp);
4875 else
4876 Otyp := Entity (Subtype_Mark (Exp));
4877 end if;
4878
4879 -- The input type always comes from the expression, and we assume
4880 -- this is indeed always analyzed, so we can simply get the Etype.
4881
4882 Ityp := Etype (Expression (Exp));
4883
4884 -- Initialize alignments to unknown so far
4885
4886 Oalign := No_Uint;
4887 Ialign := No_Uint;
4888
4889 -- Replace a concurrent type by its corresponding record type
4890 -- and each type by its underlying type and do the tests on those.
4891 -- The original type may be a private type whose completion is a
4892 -- concurrent type, so find the underlying type first.
4893
4894 if Present (Underlying_Type (Otyp)) then
4895 Otyp := Underlying_Type (Otyp);
4896 end if;
4897
4898 if Present (Underlying_Type (Ityp)) then
4899 Ityp := Underlying_Type (Ityp);
4900 end if;
4901
4902 if Is_Concurrent_Type (Otyp) then
4903 Otyp := Corresponding_Record_Type (Otyp);
4904 end if;
4905
4906 if Is_Concurrent_Type (Ityp) then
4907 Ityp := Corresponding_Record_Type (Ityp);
4908 end if;
4909
4910 -- If the base types are the same, we know there is no problem since
4911 -- this conversion will be a noop.
4912
4913 if Implementation_Base_Type (Otyp) = Implementation_Base_Type (Ityp) then
4914 return True;
4915
6cdb2c6e
AC		 4916 -- Same if this is an upwards conversion of an untagged type, and there
4917 -- are no constraints involved (could be more general???)
4918
4919 elsif Etype (Ityp) = Otyp
4920 and then not Is_Tagged_Type (Ityp)
4921 and then not Has_Discriminants (Ityp)
4922 and then No (First_Rep_Item (Base_Type (Ityp)))
4923 then
4924 return True;
4925
70482933
RK		 4926 -- If the size of output type is known at compile time, there is
4927 -- never a problem. Note that unconstrained records are considered
4928 -- to be of known size, but we can't consider them that way here,
4929 -- because we are talking about the actual size of the object.
4930
4931 -- We also make sure that in addition to the size being known, we do
4932 -- not have a case which might generate an embarrassingly large temp
4933 -- in stack checking mode.
4934
4935 elsif Size_Known_At_Compile_Time (Otyp)
7324bf49
AC		 4936 and then
4937 (not Stack_Checking_Enabled
4938 or else not May_Generate_Large_Temp (Otyp))
70482933
RK		 4939 and then not (Is_Record_Type (Otyp) and then not Is_Constrained (Otyp))
4940 then
4941 return True;
4942
4943 -- If either type is tagged, then we know the alignment is OK so
4944 -- Gigi will be able to use pointer punning.
4945
4946 elsif Is_Tagged_Type (Otyp) or else Is_Tagged_Type (Ityp) then
4947 return True;
4948
4949 -- If either type is a limited record type, we cannot do a copy, so
4950 -- say safe since there's nothing else we can do.
4951
4952 elsif Is_Limited_Record (Otyp) or else Is_Limited_Record (Ityp) then
4953 return True;
4954
4955 -- Conversions to and from packed array types are always ignored and
4956 -- hence are safe.
4957
4958 elsif Is_Packed_Array_Type (Otyp)
4959 or else Is_Packed_Array_Type (Ityp)
4960 then
4961 return True;
4962 end if;
4963
4964 -- The only other cases known to be safe is if the input type's
4965 -- alignment is known to be at least the maximum alignment for the
4966 -- target or if both alignments are known and the output type's
4967 -- alignment is no stricter than the input's. We can use the alignment
4968 -- of the component type of an array if a type is an unpacked
4969 -- array type.
4970
4971 if Present (Alignment_Clause (Otyp)) then
4972 Oalign := Expr_Value (Expression (Alignment_Clause (Otyp)));
4973
4974 elsif Is_Array_Type (Otyp)
4975 and then Present (Alignment_Clause (Component_Type (Otyp)))
4976 then
4977 Oalign := Expr_Value (Expression (Alignment_Clause
4978 (Component_Type (Otyp))));
4979 end if;
4980
4981 if Present (Alignment_Clause (Ityp)) then
4982 Ialign := Expr_Value (Expression (Alignment_Clause (Ityp)));
4983
4984 elsif Is_Array_Type (Ityp)
4985 and then Present (Alignment_Clause (Component_Type (Ityp)))
4986 then
4987 Ialign := Expr_Value (Expression (Alignment_Clause
4988 (Component_Type (Ityp))));
4989 end if;
4990
4991 if Ialign /= No_Uint and then Ialign > Maximum_Alignment then
4992 return True;
4993
4994 elsif Ialign /= No_Uint and then Oalign /= No_Uint
4995 and then Ialign <= Oalign
4996 then
4997 return True;
4998
bebbff91 4999 -- Otherwise, Gigi cannot handle this and we must make a temporary
70482933
RK		 5000
5001 else
5002 return False;
5003 end if;
70482933
RK		 5004 end Safe_Unchecked_Type_Conversion;
5005
05350ac6
BD		 5006 ---------------------------------
5007 -- Set_Current_Value_Condition --
5008 ---------------------------------
5009
5010 -- Note: the implementation of this procedure is very closely tied to the
5011 -- implementation of Get_Current_Value_Condition. Here we set required
5012 -- Current_Value fields, and in Get_Current_Value_Condition, we interpret
5013 -- them, so they must have a consistent view.
5014
5015 procedure Set_Current_Value_Condition (Cnode : Node_Id) is
5016
5017 procedure Set_Entity_Current_Value (N : Node_Id);
5018 -- If N is an entity reference, where the entity is of an appropriate
5019 -- kind, then set the current value of this entity to Cnode, unless
5020 -- there is already a definite value set there.
5021
5022 procedure Set_Expression_Current_Value (N : Node_Id);
5023 -- If N is of an appropriate form, sets an appropriate entry in current
5024 -- value fields of relevant entities. Multiple entities can be affected
5025 -- in the case of an AND or AND THEN.
5026
5027 ------------------------------
5028 -- Set_Entity_Current_Value --
5029 ------------------------------
5030
5031 procedure Set_Entity_Current_Value (N : Node_Id) is
5032 begin
5033 if Is_Entity_Name (N) then
5034 declare
5035 Ent : constant Entity_Id := Entity (N);
5036
5037 begin
5038 -- Don't capture if not safe to do so
5039
5040 if not Safe_To_Capture_Value (N, Ent, Cond => True) then
5041 return;
5042 end if;
5043
5044 -- Here we have a case where the Current_Value field may
5045 -- need to be set. We set it if it is not already set to a
5046 -- compile time expression value.
5047
5048 -- Note that this represents a decision that one condition
5049 -- blots out another previous one. That's certainly right
5050 -- if they occur at the same level. If the second one is
5051 -- nested, then the decision is neither right nor wrong (it
5052 -- would be equally OK to leave the outer one in place, or
5053 -- take the new inner one. Really we should record both, but
5054 -- our data structures are not that elaborate.
5055
5056 if Nkind (Current_Value (Ent)) not in N_Subexpr then
5057 Set_Current_Value (Ent, Cnode);
5058 end if;
5059 end;
5060 end if;
5061 end Set_Entity_Current_Value;
5062
5063 ----------------------------------
5064 -- Set_Expression_Current_Value --
5065 ----------------------------------
5066
5067 procedure Set_Expression_Current_Value (N : Node_Id) is
5068 Cond : Node_Id;
5069
5070 begin
5071 Cond := N;
5072
5073 -- Loop to deal with (ignore for now) any NOT operators present. The
5074 -- presence of NOT operators will be handled properly when we call
5075 -- Get_Current_Value_Condition.
5076
5077 while Nkind (Cond) = N_Op_Not loop
5078 Cond := Right_Opnd (Cond);
5079 end loop;
5080
5081 -- For an AND or AND THEN, recursively process operands
5082
5083 if Nkind (Cond) = N_Op_And or else Nkind (Cond) = N_And_Then then
5084 Set_Expression_Current_Value (Left_Opnd (Cond));
5085 Set_Expression_Current_Value (Right_Opnd (Cond));
5086 return;
5087 end if;
5088
5089 -- Check possible relational operator
5090
5091 if Nkind (Cond) in N_Op_Compare then
5092 if Compile_Time_Known_Value (Right_Opnd (Cond)) then
5093 Set_Entity_Current_Value (Left_Opnd (Cond));
5094 elsif Compile_Time_Known_Value (Left_Opnd (Cond)) then
5095 Set_Entity_Current_Value (Right_Opnd (Cond));
5096 end if;
5097
5098 -- Check possible boolean variable reference
5099
5100 else
5101 Set_Entity_Current_Value (Cond);
5102 end if;
5103 end Set_Expression_Current_Value;
5104
5105 -- Start of processing for Set_Current_Value_Condition
5106
5107 begin
5108 Set_Expression_Current_Value (Condition (Cnode));
5109 end Set_Current_Value_Condition;
5110
70482933
RK		 5111 --------------------------
5112 -- Set_Elaboration_Flag --
5113 --------------------------
5114
5115 procedure Set_Elaboration_Flag (N : Node_Id; Spec_Id : Entity_Id) is
5116 Loc : constant Source_Ptr := Sloc (N);
fbf5a39b 5117 Ent : constant Entity_Id := Elaboration_Entity (Spec_Id);
70482933
RK		 5118 Asn : Node_Id;
5119
5120 begin
fbf5a39b 5121 if Present (Ent) then
70482933
RK		 5122
5123 -- Nothing to do if at the compilation unit level, because in this
5124 -- case the flag is set by the binder generated elaboration routine.
5125
5126 if Nkind (Parent (N)) = N_Compilation_Unit then
5127 null;
5128
5129 -- Here we do need to generate an assignment statement
5130
5131 else
5132 Check_Restriction (No_Elaboration_Code, N);
5133 Asn :=
5134 Make_Assignment_Statement (Loc,
fbf5a39b 5135 Name => New_Occurrence_Of (Ent, Loc),
70482933
RK		 5136 Expression => New_Occurrence_Of (Standard_True, Loc));
5137
5138 if Nkind (Parent (N)) = N_Subunit then
5139 Insert_After (Corresponding_Stub (Parent (N)), Asn);
5140 else
5141 Insert_After (N, Asn);
5142 end if;
5143
5144 Analyze (Asn);
fbf5a39b
AC		 5145
5146 -- Kill current value indication. This is necessary because
5147 -- the tests of this flag are inserted out of sequence and must
5148 -- not pick up bogus indications of the wrong constant value.
5149
5150 Set_Current_Value (Ent, Empty);
70482933
RK		 5151 end if;
5152 end if;
5153 end Set_Elaboration_Flag;
5154
59e54267
ES		 5155 ----------------------------
5156 -- Set_Renamed_Subprogram --
5157 ----------------------------
5158
5159 procedure Set_Renamed_Subprogram (N : Node_Id; E : Entity_Id) is
5160 begin
5161 -- If input node is an identifier, we can just reset it
5162
5163 if Nkind (N) = N_Identifier then
5164 Set_Chars (N, Chars (E));
5165 Set_Entity (N, E);
5166
5167 -- Otherwise we have to do a rewrite, preserving Comes_From_Source
5168
5169 else
5170 declare
5171 CS : constant Boolean := Comes_From_Source (N);
5172 begin
5173 Rewrite (N, Make_Identifier (Sloc (N), Chars => Chars (E)));
5174 Set_Entity (N, E);
5175 Set_Comes_From_Source (N, CS);
5176 Set_Analyzed (N, True);
5177 end;
5178 end if;
5179 end Set_Renamed_Subprogram;
5180
fbf5a39b
AC		 5181 --------------------------
5182 -- Target_Has_Fixed_Ops --
5183 --------------------------
5184
5185 Integer_Sized_Small : Ureal;
5186 -- Set to 2.0 ** -(Integer'Size - 1) the first time that this
5187 -- function is called (we don't want to compute it more than once!)
5188
5189 Long_Integer_Sized_Small : Ureal;
5190 -- Set to 2.0 ** -(Long_Integer'Size - 1) the first time that this
5191 -- functoin is called (we don't want to compute it more than once)
5192
5193 First_Time_For_THFO : Boolean := True;
5194 -- Set to False after first call (if Fractional_Fixed_Ops_On_Target)
5195
5196 function Target_Has_Fixed_Ops
5197 (Left_Typ : Entity_Id;
5198 Right_Typ : Entity_Id;
bebbff91 5199 Result_Typ : Entity_Id) return Boolean
fbf5a39b
AC		 5200 is
5201 function Is_Fractional_Type (Typ : Entity_Id) return Boolean;
5202 -- Return True if the given type is a fixed-point type with a small
5203 -- value equal to 2 ** (-(T'Object_Size - 1)) and whose values have
5204 -- an absolute value less than 1.0. This is currently limited
5205 -- to fixed-point types that map to Integer or Long_Integer.
5206
5207 ------------------------
5208 -- Is_Fractional_Type --
5209 ------------------------
5210
5211 function Is_Fractional_Type (Typ : Entity_Id) return Boolean is
5212 begin
5213 if Esize (Typ) = Standard_Integer_Size then
5214 return Small_Value (Typ) = Integer_Sized_Small;
5215
5216 elsif Esize (Typ) = Standard_Long_Integer_Size then
5217 return Small_Value (Typ) = Long_Integer_Sized_Small;
5218
5219 else
5220 return False;
5221 end if;
5222 end Is_Fractional_Type;
5223
5224 -- Start of processing for Target_Has_Fixed_Ops
5225
5226 begin
5227 -- Return False if Fractional_Fixed_Ops_On_Target is false
5228
5229 if not Fractional_Fixed_Ops_On_Target then
5230 return False;
5231 end if;
5232
5233 -- Here the target has Fractional_Fixed_Ops, if first time, compute
5234 -- standard constants used by Is_Fractional_Type.
5235
5236 if First_Time_For_THFO then
5237 First_Time_For_THFO := False;
5238
5239 Integer_Sized_Small :=
5240 UR_From_Components
5241 (Num => Uint_1,
5242 Den => UI_From_Int (Standard_Integer_Size - 1),
5243 Rbase => 2);
5244
5245 Long_Integer_Sized_Small :=
5246 UR_From_Components
5247 (Num => Uint_1,
5248 Den => UI_From_Int (Standard_Long_Integer_Size - 1),
5249 Rbase => 2);
5250 end if;
5251
5252 -- Return True if target supports fixed-by-fixed multiply/divide
5253 -- for fractional fixed-point types (see Is_Fractional_Type) and
5254 -- the operand and result types are equivalent fractional types.
5255
5256 return Is_Fractional_Type (Base_Type (Left_Typ))
5257 and then Is_Fractional_Type (Base_Type (Right_Typ))
5258 and then Is_Fractional_Type (Base_Type (Result_Typ))
5259 and then Esize (Left_Typ) = Esize (Right_Typ)
5260 and then Esize (Left_Typ) = Esize (Result_Typ);
5261 end Target_Has_Fixed_Ops;
5262
91b1417d
AC		 5263 ------------------------------------------
5264 -- Type_May_Have_Bit_Aligned_Components --
5265 ------------------------------------------
5266
5267 function Type_May_Have_Bit_Aligned_Components
5268 (Typ : Entity_Id) return Boolean
5269 is
5270 begin
5271 -- Array type, check component type
5272
5273 if Is_Array_Type (Typ) then
5274 return
5275 Type_May_Have_Bit_Aligned_Components (Component_Type (Typ));
5276
5277 -- Record type, check components
5278
5279 elsif Is_Record_Type (Typ) then
5280 declare
5281 E : Entity_Id;
5282
5283 begin
dee4682a 5284 E := First_Component_Or_Discriminant (Typ);
91b1417d 5285 while Present (E) loop
dee4682a
JM		 5286 if Component_May_Be_Bit_Aligned (E)
5287 or else Type_May_Have_Bit_Aligned_Components (Etype (E))
91b1417d 5288 then
dee4682a 5289 return True;
91b1417d
AC		 5290 end if;
5291
dee4682a 5292 Next_Component_Or_Discriminant (E);
91b1417d
AC		 5293 end loop;
5294
5295 return False;
5296 end;
5297
5298 -- Type other than array or record is always OK
5299
5300 else
5301 return False;
5302 end if;
5303 end Type_May_Have_Bit_Aligned_Components;
5304
70482933
RK		 5305 ----------------------------
5306 -- Wrap_Cleanup_Procedure --
5307 ----------------------------
5308
5309 procedure Wrap_Cleanup_Procedure (N : Node_Id) is
5310 Loc : constant Source_Ptr := Sloc (N);
5311 Stseq : constant Node_Id := Handled_Statement_Sequence (N);
5312 Stmts : constant List_Id := Statements (Stseq);
5313
5314 begin
5315 if Abort_Allowed then
5316 Prepend_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Defer));
5317 Append_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Undefer));
5318 end if;
5319 end Wrap_Cleanup_Procedure;
5320
5321end Exp_Util;
GNU Compiler Collection
This page took 1.726681 seconds and 5 git commands to generate.