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d6f39728 | 1 | ------------------------------------------------------------------------------ |
7189d17f | 2 | -- -- |
d6f39728 | 3 | -- GNAT COMPILER COMPONENTS -- |
4 | -- -- | |
5 | -- S E M _ C H 1 3 -- | |
6 | -- -- | |
7 | -- B o d y -- | |
8 | -- -- | |
87d5c1d0 | 9 | -- Copyright (C) 1992-2006, Free Software Foundation, Inc. -- |
d6f39728 | 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 -- | |
f27cea3a | 19 | -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, -- |
20 | -- Boston, MA 02110-1301, USA. -- | |
d6f39728 | 21 | -- -- |
22 | -- GNAT was originally developed by the GNAT team at New York University. -- | |
e78e8c8e | 23 | -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
d6f39728 | 24 | -- -- |
25 | ------------------------------------------------------------------------------ | |
26 | ||
27 | with Atree; use Atree; | |
713c00d6 | 28 | with Checks; use Checks; |
d6f39728 | 29 | with Einfo; use Einfo; |
30 | with Errout; use Errout; | |
31 | with Exp_Tss; use Exp_Tss; | |
32 | with Exp_Util; use Exp_Util; | |
d6f39728 | 33 | with Lib; use Lib; |
34 | with Nlists; use Nlists; | |
35 | with Nmake; use Nmake; | |
36 | with Opt; use Opt; | |
e0521a36 | 37 | with Restrict; use Restrict; |
38 | with Rident; use Rident; | |
d6f39728 | 39 | with Rtsfind; use Rtsfind; |
40 | with Sem; use Sem; | |
41 | with Sem_Ch8; use Sem_Ch8; | |
42 | with Sem_Eval; use Sem_Eval; | |
43 | with Sem_Res; use Sem_Res; | |
44 | with Sem_Type; use Sem_Type; | |
45 | with Sem_Util; use Sem_Util; | |
9dfe12ae | 46 | with Snames; use Snames; |
d6f39728 | 47 | with Stand; use Stand; |
48 | with Sinfo; use Sinfo; | |
d6f39728 | 49 | with Table; |
93735cb8 | 50 | with Targparm; use Targparm; |
d6f39728 | 51 | with Ttypes; use Ttypes; |
52 | with Tbuild; use Tbuild; | |
53 | with Urealp; use Urealp; | |
54 | ||
55 | with GNAT.Heap_Sort_A; use GNAT.Heap_Sort_A; | |
56 | ||
57 | package body Sem_Ch13 is | |
58 | ||
59 | SSU : constant Pos := System_Storage_Unit; | |
60 | -- Convenient short hand for commonly used constant | |
61 | ||
62 | ----------------------- | |
63 | -- Local Subprograms -- | |
64 | ----------------------- | |
65 | ||
66 | procedure Alignment_Check_For_Esize_Change (Typ : Entity_Id); | |
67 | -- This routine is called after setting the Esize of type entity Typ. | |
68 | -- The purpose is to deal with the situation where an aligment has been | |
69 | -- inherited from a derived type that is no longer appropriate for the | |
70 | -- new Esize value. In this case, we reset the Alignment to unknown. | |
71 | ||
d6f39728 | 72 | procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id); |
73 | -- Given two entities for record components or discriminants, checks | |
74 | -- if they hav overlapping component clauses and issues errors if so. | |
75 | ||
76 | function Get_Alignment_Value (Expr : Node_Id) return Uint; | |
77 | -- Given the expression for an alignment value, returns the corresponding | |
78 | -- Uint value. If the value is inappropriate, then error messages are | |
79 | -- posted as required, and a value of No_Uint is returned. | |
80 | ||
81 | function Is_Operational_Item (N : Node_Id) return Boolean; | |
82 | -- A specification for a stream attribute is allowed before the full | |
83 | -- type is declared, as explained in AI-00137 and the corrigendum. | |
84 | -- Attributes that do not specify a representation characteristic are | |
85 | -- operational attributes. | |
86 | ||
9dfe12ae | 87 | function Address_Aliased_Entity (N : Node_Id) return Entity_Id; |
2866d595 | 88 | -- If expression N is of the form E'Address, return E |
9dfe12ae | 89 | |
90 | procedure Mark_Aliased_Address_As_Volatile (N : Node_Id); | |
91 | -- This is used for processing of an address representation clause. If | |
92 | -- the expression N is of the form of K'Address, then the entity that | |
93 | -- is associated with K is marked as volatile. | |
94 | ||
d6f39728 | 95 | procedure New_Stream_Function |
96 | (N : Node_Id; | |
97 | Ent : Entity_Id; | |
98 | Subp : Entity_Id; | |
9dfe12ae | 99 | Nam : TSS_Name_Type); |
d6f39728 | 100 | -- Create a function renaming of a given stream attribute to the |
101 | -- designated subprogram and then in the tagged case, provide this as | |
102 | -- a primitive operation, or in the non-tagged case make an appropriate | |
103 | -- TSS entry. Used for Input. This is more properly an expansion activity | |
104 | -- than just semantics, but the presence of user-defined stream functions | |
105 | -- for limited types is a legality check, which is why this takes place | |
9dfe12ae | 106 | -- here rather than in exp_ch13, where it was previously. Nam indicates |
107 | -- the name of the TSS function to be generated. | |
108 | -- | |
f15731c4 | 109 | -- To avoid elaboration anomalies with freeze nodes, for untagged types |
110 | -- we generate both a subprogram declaration and a subprogram renaming | |
111 | -- declaration, so that the attribute specification is handled as a | |
112 | -- renaming_as_body. For tagged types, the specification is one of the | |
113 | -- primitive specs. | |
114 | ||
d6f39728 | 115 | procedure New_Stream_Procedure |
116 | (N : Node_Id; | |
117 | Ent : Entity_Id; | |
118 | Subp : Entity_Id; | |
9dfe12ae | 119 | Nam : TSS_Name_Type; |
d6f39728 | 120 | Out_P : Boolean := False); |
121 | -- Create a procedure renaming of a given stream attribute to the | |
122 | -- designated subprogram and then in the tagged case, provide this as | |
123 | -- a primitive operation, or in the non-tagged case make an appropriate | |
9dfe12ae | 124 | -- TSS entry. Used for Read, Output, Write. Nam indicates the name of |
125 | -- the TSS procedure to be generated. | |
d6f39728 | 126 | |
127 | ---------------------------------------------- | |
128 | -- Table for Validate_Unchecked_Conversions -- | |
129 | ---------------------------------------------- | |
130 | ||
131 | -- The following table collects unchecked conversions for validation. | |
132 | -- Entries are made by Validate_Unchecked_Conversion and then the | |
133 | -- call to Validate_Unchecked_Conversions does the actual error | |
134 | -- checking and posting of warnings. The reason for this delayed | |
135 | -- processing is to take advantage of back-annotations of size and | |
136 | -- alignment values peformed by the back end. | |
137 | ||
138 | type UC_Entry is record | |
139 | Enode : Node_Id; -- node used for posting warnings | |
140 | Source : Entity_Id; -- source type for unchecked conversion | |
141 | Target : Entity_Id; -- target type for unchecked conversion | |
142 | end record; | |
143 | ||
144 | package Unchecked_Conversions is new Table.Table ( | |
145 | Table_Component_Type => UC_Entry, | |
146 | Table_Index_Type => Int, | |
147 | Table_Low_Bound => 1, | |
148 | Table_Initial => 50, | |
149 | Table_Increment => 200, | |
150 | Table_Name => "Unchecked_Conversions"); | |
151 | ||
9dfe12ae | 152 | ---------------------------- |
153 | -- Address_Aliased_Entity -- | |
154 | ---------------------------- | |
155 | ||
156 | function Address_Aliased_Entity (N : Node_Id) return Entity_Id is | |
157 | begin | |
158 | if Nkind (N) = N_Attribute_Reference | |
159 | and then Attribute_Name (N) = Name_Address | |
160 | then | |
161 | declare | |
162 | Nam : Node_Id := Prefix (N); | |
163 | begin | |
164 | while False | |
165 | or else Nkind (Nam) = N_Selected_Component | |
166 | or else Nkind (Nam) = N_Indexed_Component | |
167 | loop | |
168 | Nam := Prefix (Nam); | |
169 | end loop; | |
170 | ||
171 | if Is_Entity_Name (Nam) then | |
172 | return Entity (Nam); | |
173 | end if; | |
174 | end; | |
175 | end if; | |
176 | ||
177 | return Empty; | |
178 | end Address_Aliased_Entity; | |
179 | ||
d6f39728 | 180 | -------------------------------------- |
181 | -- Alignment_Check_For_Esize_Change -- | |
182 | -------------------------------------- | |
183 | ||
184 | procedure Alignment_Check_For_Esize_Change (Typ : Entity_Id) is | |
185 | begin | |
186 | -- If the alignment is known, and not set by a rep clause, and is | |
187 | -- inconsistent with the size being set, then reset it to unknown, | |
188 | -- we assume in this case that the size overrides the inherited | |
189 | -- alignment, and that the alignment must be recomputed. | |
190 | ||
191 | if Known_Alignment (Typ) | |
192 | and then not Has_Alignment_Clause (Typ) | |
193 | and then Esize (Typ) mod (Alignment (Typ) * SSU) /= 0 | |
194 | then | |
195 | Init_Alignment (Typ); | |
196 | end if; | |
197 | end Alignment_Check_For_Esize_Change; | |
198 | ||
199 | ----------------------- | |
200 | -- Analyze_At_Clause -- | |
201 | ----------------------- | |
202 | ||
203 | -- An at clause is replaced by the corresponding Address attribute | |
204 | -- definition clause that is the preferred approach in Ada 95. | |
205 | ||
206 | procedure Analyze_At_Clause (N : Node_Id) is | |
207 | begin | |
e0521a36 | 208 | Check_Restriction (No_Obsolescent_Features, N); |
209 | ||
9dfe12ae | 210 | if Warn_On_Obsolescent_Feature then |
211 | Error_Msg_N | |
212 | ("at clause is an obsolescent feature ('R'M 'J.7(2))?", N); | |
213 | Error_Msg_N | |
d53a018a | 214 | ("\use address attribute definition clause instead?", N); |
9dfe12ae | 215 | end if; |
216 | ||
d6f39728 | 217 | Rewrite (N, |
218 | Make_Attribute_Definition_Clause (Sloc (N), | |
219 | Name => Identifier (N), | |
220 | Chars => Name_Address, | |
221 | Expression => Expression (N))); | |
222 | Analyze_Attribute_Definition_Clause (N); | |
223 | end Analyze_At_Clause; | |
224 | ||
225 | ----------------------------------------- | |
226 | -- Analyze_Attribute_Definition_Clause -- | |
227 | ----------------------------------------- | |
228 | ||
229 | procedure Analyze_Attribute_Definition_Clause (N : Node_Id) is | |
230 | Loc : constant Source_Ptr := Sloc (N); | |
231 | Nam : constant Node_Id := Name (N); | |
232 | Attr : constant Name_Id := Chars (N); | |
233 | Expr : constant Node_Id := Expression (N); | |
234 | Id : constant Attribute_Id := Get_Attribute_Id (Attr); | |
235 | Ent : Entity_Id; | |
236 | U_Ent : Entity_Id; | |
237 | ||
238 | FOnly : Boolean := False; | |
239 | -- Reset to True for subtype specific attribute (Alignment, Size) | |
240 | -- and for stream attributes, i.e. those cases where in the call | |
241 | -- to Rep_Item_Too_Late, FOnly is set True so that only the freezing | |
242 | -- rules are checked. Note that the case of stream attributes is not | |
243 | -- clear from the RM, but see AI95-00137. Also, the RM seems to | |
244 | -- disallow Storage_Size for derived task types, but that is also | |
245 | -- clearly unintentional. | |
246 | ||
9f373bb8 | 247 | procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type); |
248 | -- Common processing for 'Read, 'Write, 'Input and 'Output attribute | |
249 | -- definition clauses. | |
250 | ||
251 | procedure Analyze_Stream_TSS_Definition (TSS_Nam : TSS_Name_Type) is | |
252 | Subp : Entity_Id := Empty; | |
253 | I : Interp_Index; | |
254 | It : Interp; | |
255 | Pnam : Entity_Id; | |
256 | ||
257 | Is_Read : constant Boolean := (TSS_Nam = TSS_Stream_Read); | |
258 | ||
259 | function Has_Good_Profile (Subp : Entity_Id) return Boolean; | |
260 | -- Return true if the entity is a subprogram with an appropriate | |
261 | -- profile for the attribute being defined. | |
262 | ||
263 | ---------------------- | |
264 | -- Has_Good_Profile -- | |
265 | ---------------------- | |
266 | ||
267 | function Has_Good_Profile (Subp : Entity_Id) return Boolean is | |
268 | F : Entity_Id; | |
269 | Is_Function : constant Boolean := (TSS_Nam = TSS_Stream_Input); | |
270 | Expected_Ekind : constant array (Boolean) of Entity_Kind := | |
271 | (False => E_Procedure, True => E_Function); | |
272 | Typ : Entity_Id; | |
273 | ||
274 | begin | |
275 | if Ekind (Subp) /= Expected_Ekind (Is_Function) then | |
276 | return False; | |
277 | end if; | |
278 | ||
279 | F := First_Formal (Subp); | |
280 | ||
281 | if No (F) | |
282 | or else Ekind (Etype (F)) /= E_Anonymous_Access_Type | |
283 | or else Designated_Type (Etype (F)) /= | |
284 | Class_Wide_Type (RTE (RE_Root_Stream_Type)) | |
285 | then | |
286 | return False; | |
287 | end if; | |
288 | ||
289 | if not Is_Function then | |
290 | Next_Formal (F); | |
291 | ||
292 | declare | |
293 | Expected_Mode : constant array (Boolean) of Entity_Kind := | |
294 | (False => E_In_Parameter, | |
295 | True => E_Out_Parameter); | |
296 | begin | |
297 | if Parameter_Mode (F) /= Expected_Mode (Is_Read) then | |
298 | return False; | |
299 | end if; | |
300 | end; | |
301 | ||
302 | Typ := Etype (F); | |
303 | ||
304 | else | |
305 | Typ := Etype (Subp); | |
306 | end if; | |
307 | ||
308 | return Base_Type (Typ) = Base_Type (Ent) | |
309 | and then No (Next_Formal (F)); | |
310 | ||
311 | end Has_Good_Profile; | |
312 | ||
313 | -- Start of processing for Analyze_Stream_TSS_Definition | |
314 | ||
315 | begin | |
316 | FOnly := True; | |
317 | ||
318 | if not Is_Type (U_Ent) then | |
319 | Error_Msg_N ("local name must be a subtype", Nam); | |
320 | return; | |
321 | end if; | |
322 | ||
323 | Pnam := TSS (Base_Type (U_Ent), TSS_Nam); | |
324 | ||
325 | if Present (Pnam) and then Has_Good_Profile (Pnam) then | |
326 | Error_Msg_Sloc := Sloc (Pnam); | |
327 | Error_Msg_Name_1 := Attr; | |
328 | Error_Msg_N ("% attribute already defined #", Nam); | |
329 | return; | |
330 | end if; | |
331 | ||
332 | Analyze (Expr); | |
333 | ||
334 | if Is_Entity_Name (Expr) then | |
335 | if not Is_Overloaded (Expr) then | |
336 | if Has_Good_Profile (Entity (Expr)) then | |
337 | Subp := Entity (Expr); | |
338 | end if; | |
339 | ||
340 | else | |
341 | Get_First_Interp (Expr, I, It); | |
342 | ||
343 | while Present (It.Nam) loop | |
344 | if Has_Good_Profile (It.Nam) then | |
345 | Subp := It.Nam; | |
346 | exit; | |
347 | end if; | |
348 | ||
349 | Get_Next_Interp (I, It); | |
350 | end loop; | |
351 | end if; | |
352 | end if; | |
353 | ||
354 | if Present (Subp) then | |
355 | if Is_Abstract (Subp) then | |
356 | Error_Msg_N ("stream subprogram must not be abstract", Expr); | |
357 | return; | |
358 | end if; | |
359 | ||
360 | Set_Entity (Expr, Subp); | |
361 | Set_Etype (Expr, Etype (Subp)); | |
362 | ||
363 | if TSS_Nam = TSS_Stream_Input then | |
364 | New_Stream_Function (N, U_Ent, Subp, TSS_Nam); | |
365 | else | |
366 | New_Stream_Procedure (N, U_Ent, Subp, TSS_Nam, | |
367 | Out_P => Is_Read); | |
368 | end if; | |
369 | ||
370 | else | |
371 | Error_Msg_Name_1 := Attr; | |
372 | Error_Msg_N ("incorrect expression for% attribute", Expr); | |
373 | end if; | |
374 | end Analyze_Stream_TSS_Definition; | |
375 | ||
376 | -- Start of processing for Analyze_Attribute_Definition_Clause | |
377 | ||
d6f39728 | 378 | begin |
379 | Analyze (Nam); | |
380 | Ent := Entity (Nam); | |
381 | ||
382 | if Rep_Item_Too_Early (Ent, N) then | |
383 | return; | |
384 | end if; | |
385 | ||
9f373bb8 | 386 | -- Rep clause applies to full view of incomplete type or private type if |
387 | -- we have one (if not, this is a premature use of the type). However, | |
388 | -- certain semantic checks need to be done on the specified entity (i.e. | |
389 | -- the private view), so we save it in Ent. | |
d6f39728 | 390 | |
391 | if Is_Private_Type (Ent) | |
392 | and then Is_Derived_Type (Ent) | |
393 | and then not Is_Tagged_Type (Ent) | |
394 | and then No (Full_View (Ent)) | |
395 | then | |
9f373bb8 | 396 | -- If this is a private type whose completion is a derivation from |
397 | -- another private type, there is no full view, and the attribute | |
398 | -- belongs to the type itself, not its underlying parent. | |
d6f39728 | 399 | |
400 | U_Ent := Ent; | |
401 | ||
402 | elsif Ekind (Ent) = E_Incomplete_Type then | |
d5b349fa | 403 | |
9f373bb8 | 404 | -- The attribute applies to the full view, set the entity of the |
405 | -- attribute definition accordingly. | |
d5b349fa | 406 | |
d6f39728 | 407 | Ent := Underlying_Type (Ent); |
408 | U_Ent := Ent; | |
d5b349fa | 409 | Set_Entity (Nam, Ent); |
410 | ||
d6f39728 | 411 | else |
412 | U_Ent := Underlying_Type (Ent); | |
413 | end if; | |
414 | ||
415 | -- Complete other routine error checks | |
416 | ||
417 | if Etype (Nam) = Any_Type then | |
418 | return; | |
419 | ||
420 | elsif Scope (Ent) /= Current_Scope then | |
421 | Error_Msg_N ("entity must be declared in this scope", Nam); | |
422 | return; | |
423 | ||
f15731c4 | 424 | elsif No (U_Ent) then |
425 | U_Ent := Ent; | |
426 | ||
d6f39728 | 427 | elsif Is_Type (U_Ent) |
428 | and then not Is_First_Subtype (U_Ent) | |
429 | and then Id /= Attribute_Object_Size | |
430 | and then Id /= Attribute_Value_Size | |
431 | and then not From_At_Mod (N) | |
432 | then | |
433 | Error_Msg_N ("cannot specify attribute for subtype", Nam); | |
434 | return; | |
d6f39728 | 435 | end if; |
436 | ||
437 | -- Switch on particular attribute | |
438 | ||
439 | case Id is | |
440 | ||
441 | ------------- | |
442 | -- Address -- | |
443 | ------------- | |
444 | ||
445 | -- Address attribute definition clause | |
446 | ||
447 | when Attribute_Address => Address : begin | |
448 | Analyze_And_Resolve (Expr, RTE (RE_Address)); | |
449 | ||
450 | if Present (Address_Clause (U_Ent)) then | |
451 | Error_Msg_N ("address already given for &", Nam); | |
452 | ||
453 | -- Case of address clause for subprogram | |
454 | ||
455 | elsif Is_Subprogram (U_Ent) then | |
d6f39728 | 456 | if Has_Homonym (U_Ent) then |
457 | Error_Msg_N | |
458 | ("address clause cannot be given " & | |
459 | "for overloaded subprogram", | |
460 | Nam); | |
461 | end if; | |
462 | ||
463 | -- For subprograms, all address clauses are permitted, | |
464 | -- and we mark the subprogram as having a deferred freeze | |
465 | -- so that Gigi will not elaborate it too soon. | |
466 | ||
467 | -- Above needs more comments, what is too soon about??? | |
468 | ||
469 | Set_Has_Delayed_Freeze (U_Ent); | |
470 | ||
471 | -- Case of address clause for entry | |
472 | ||
473 | elsif Ekind (U_Ent) = E_Entry then | |
d6f39728 | 474 | if Nkind (Parent (N)) = N_Task_Body then |
475 | Error_Msg_N | |
476 | ("entry address must be specified in task spec", Nam); | |
477 | end if; | |
478 | ||
479 | -- For entries, we require a constant address | |
480 | ||
481 | Check_Constant_Address_Clause (Expr, U_Ent); | |
482 | ||
f15731c4 | 483 | if Is_Task_Type (Scope (U_Ent)) |
484 | and then Comes_From_Source (Scope (U_Ent)) | |
485 | then | |
486 | Error_Msg_N | |
487 | ("?entry address declared for entry in task type", N); | |
488 | Error_Msg_N | |
489 | ("\?only one task can be declared of this type", N); | |
490 | end if; | |
491 | ||
e0521a36 | 492 | Check_Restriction (No_Obsolescent_Features, N); |
493 | ||
9dfe12ae | 494 | if Warn_On_Obsolescent_Feature then |
495 | Error_Msg_N | |
496 | ("attaching interrupt to task entry is an " & | |
497 | "obsolescent feature ('R'M 'J.7.1)?", N); | |
498 | Error_Msg_N | |
d53a018a | 499 | ("\use interrupt procedure instead?", N); |
9dfe12ae | 500 | end if; |
501 | ||
502 | -- Case of an address clause for a controlled object: | |
503 | -- erroneous execution. | |
504 | ||
505 | elsif Is_Controlled (Etype (U_Ent)) then | |
506 | Error_Msg_NE | |
507 | ("?controlled object& must not be overlaid", Nam, U_Ent); | |
508 | Error_Msg_N | |
509 | ("\?Program_Error will be raised at run time", Nam); | |
510 | Insert_Action (Declaration_Node (U_Ent), | |
511 | Make_Raise_Program_Error (Loc, | |
512 | Reason => PE_Overlaid_Controlled_Object)); | |
513 | ||
514 | -- Case of address clause for a (non-controlled) object | |
d6f39728 | 515 | |
516 | elsif | |
517 | Ekind (U_Ent) = E_Variable | |
518 | or else | |
519 | Ekind (U_Ent) = E_Constant | |
520 | then | |
521 | declare | |
d6f39728 | 522 | Expr : constant Node_Id := Expression (N); |
9dfe12ae | 523 | Aent : constant Entity_Id := Address_Aliased_Entity (Expr); |
d6f39728 | 524 | |
525 | begin | |
526 | -- Exported variables cannot have an address clause, | |
527 | -- because this cancels the effect of the pragma Export | |
528 | ||
529 | if Is_Exported (U_Ent) then | |
530 | Error_Msg_N | |
531 | ("cannot export object with address clause", Nam); | |
532 | ||
9dfe12ae | 533 | -- Overlaying controlled objects is erroneous |
534 | ||
535 | elsif Present (Aent) | |
536 | and then Is_Controlled (Etype (Aent)) | |
537 | then | |
538 | Error_Msg_N | |
539 | ("?controlled object must not be overlaid", Expr); | |
540 | Error_Msg_N | |
541 | ("\?Program_Error will be raised at run time", Expr); | |
542 | Insert_Action (Declaration_Node (U_Ent), | |
543 | Make_Raise_Program_Error (Loc, | |
544 | Reason => PE_Overlaid_Controlled_Object)); | |
545 | ||
546 | elsif Present (Aent) | |
547 | and then Ekind (U_Ent) = E_Constant | |
548 | and then Ekind (Aent) /= E_Constant | |
549 | then | |
550 | Error_Msg_N ("constant overlays a variable?", Expr); | |
551 | ||
552 | elsif Present (Renamed_Object (U_Ent)) then | |
553 | Error_Msg_N | |
554 | ("address clause not allowed" | |
555 | & " for a renaming declaration ('R'M 13.1(6))", Nam); | |
556 | ||
d6f39728 | 557 | -- Imported variables can have an address clause, but then |
558 | -- the import is pretty meaningless except to suppress | |
559 | -- initializations, so we do not need such variables to | |
560 | -- be statically allocated (and in fact it causes trouble | |
561 | -- if the address clause is a local value). | |
562 | ||
563 | elsif Is_Imported (U_Ent) then | |
564 | Set_Is_Statically_Allocated (U_Ent, False); | |
565 | end if; | |
566 | ||
567 | -- We mark a possible modification of a variable with an | |
568 | -- address clause, since it is likely aliasing is occurring. | |
569 | ||
570 | Note_Possible_Modification (Nam); | |
571 | ||
9dfe12ae | 572 | -- Here we are checking for explicit overlap of one |
573 | -- variable by another, and if we find this, then we | |
574 | -- mark the overlapped variable as also being aliased. | |
d6f39728 | 575 | |
9dfe12ae | 576 | -- First case is where we have an explicit |
d6f39728 | 577 | |
9dfe12ae | 578 | -- for J'Address use K'Address; |
d6f39728 | 579 | |
9dfe12ae | 580 | -- In this case, we mark K as volatile |
d6f39728 | 581 | |
9dfe12ae | 582 | Mark_Aliased_Address_As_Volatile (Expr); |
d6f39728 | 583 | |
9dfe12ae | 584 | -- Second case is where we have a constant whose |
3c8148a6 | 585 | -- definition is of the form of an address as in: |
d6f39728 | 586 | |
9dfe12ae | 587 | -- A : constant Address := K'Address; |
588 | -- ... | |
589 | -- for B'Address use A; | |
d6f39728 | 590 | |
9dfe12ae | 591 | -- In this case we also mark K as volatile |
592 | ||
593 | if Is_Entity_Name (Expr) then | |
594 | declare | |
595 | Ent : constant Entity_Id := Entity (Expr); | |
596 | Decl : constant Node_Id := Declaration_Node (Ent); | |
597 | ||
598 | begin | |
599 | if Ekind (Ent) = E_Constant | |
600 | and then Nkind (Decl) = N_Object_Declaration | |
601 | and then Present (Expression (Decl)) | |
602 | then | |
603 | Mark_Aliased_Address_As_Volatile | |
604 | (Expression (Decl)); | |
605 | end if; | |
606 | end; | |
d6f39728 | 607 | end if; |
608 | ||
9dfe12ae | 609 | -- Legality checks on the address clause for initialized |
610 | -- objects is deferred until the freeze point, because | |
611 | -- a subsequent pragma might indicate that the object is | |
612 | -- imported and thus not initialized. | |
613 | ||
614 | Set_Has_Delayed_Freeze (U_Ent); | |
615 | ||
d6f39728 | 616 | if Is_Exported (U_Ent) then |
617 | Error_Msg_N | |
618 | ("& cannot be exported if an address clause is given", | |
619 | Nam); | |
620 | Error_Msg_N | |
621 | ("\define and export a variable " & | |
622 | "that holds its address instead", | |
623 | Nam); | |
624 | end if; | |
625 | ||
9dfe12ae | 626 | -- Entity has delayed freeze, so we will generate |
627 | -- an alignment check at the freeze point. | |
d6f39728 | 628 | |
9dfe12ae | 629 | Set_Check_Address_Alignment |
630 | (N, not Range_Checks_Suppressed (U_Ent)); | |
d6f39728 | 631 | |
632 | -- Kill the size check code, since we are not allocating | |
633 | -- the variable, it is somewhere else. | |
634 | ||
635 | Kill_Size_Check_Code (U_Ent); | |
636 | end; | |
637 | ||
638 | -- Not a valid entity for an address clause | |
639 | ||
640 | else | |
641 | Error_Msg_N ("address cannot be given for &", Nam); | |
642 | end if; | |
643 | end Address; | |
644 | ||
645 | --------------- | |
646 | -- Alignment -- | |
647 | --------------- | |
648 | ||
649 | -- Alignment attribute definition clause | |
650 | ||
651 | when Attribute_Alignment => Alignment_Block : declare | |
9dfe12ae | 652 | Align : constant Uint := Get_Alignment_Value (Expr); |
d6f39728 | 653 | |
654 | begin | |
655 | FOnly := True; | |
656 | ||
657 | if not Is_Type (U_Ent) | |
658 | and then Ekind (U_Ent) /= E_Variable | |
659 | and then Ekind (U_Ent) /= E_Constant | |
660 | then | |
661 | Error_Msg_N ("alignment cannot be given for &", Nam); | |
662 | ||
663 | elsif Has_Alignment_Clause (U_Ent) then | |
664 | Error_Msg_Sloc := Sloc (Alignment_Clause (U_Ent)); | |
665 | Error_Msg_N ("alignment clause previously given#", N); | |
666 | ||
667 | elsif Align /= No_Uint then | |
668 | Set_Has_Alignment_Clause (U_Ent); | |
669 | Set_Alignment (U_Ent, Align); | |
670 | end if; | |
671 | end Alignment_Block; | |
672 | ||
673 | --------------- | |
674 | -- Bit_Order -- | |
675 | --------------- | |
676 | ||
677 | -- Bit_Order attribute definition clause | |
678 | ||
679 | when Attribute_Bit_Order => Bit_Order : declare | |
680 | begin | |
681 | if not Is_Record_Type (U_Ent) then | |
682 | Error_Msg_N | |
683 | ("Bit_Order can only be defined for record type", Nam); | |
684 | ||
685 | else | |
686 | Analyze_And_Resolve (Expr, RTE (RE_Bit_Order)); | |
687 | ||
688 | if Etype (Expr) = Any_Type then | |
689 | return; | |
690 | ||
691 | elsif not Is_Static_Expression (Expr) then | |
9dfe12ae | 692 | Flag_Non_Static_Expr |
693 | ("Bit_Order requires static expression!", Expr); | |
d6f39728 | 694 | |
695 | else | |
696 | if (Expr_Value (Expr) = 0) /= Bytes_Big_Endian then | |
697 | Set_Reverse_Bit_Order (U_Ent, True); | |
698 | end if; | |
699 | end if; | |
700 | end if; | |
701 | end Bit_Order; | |
702 | ||
703 | -------------------- | |
704 | -- Component_Size -- | |
705 | -------------------- | |
706 | ||
707 | -- Component_Size attribute definition clause | |
708 | ||
709 | when Attribute_Component_Size => Component_Size_Case : declare | |
710 | Csize : constant Uint := Static_Integer (Expr); | |
711 | Btype : Entity_Id; | |
712 | Biased : Boolean; | |
713 | New_Ctyp : Entity_Id; | |
714 | Decl : Node_Id; | |
715 | ||
716 | begin | |
717 | if not Is_Array_Type (U_Ent) then | |
718 | Error_Msg_N ("component size requires array type", Nam); | |
719 | return; | |
720 | end if; | |
721 | ||
722 | Btype := Base_Type (U_Ent); | |
723 | ||
724 | if Has_Component_Size_Clause (Btype) then | |
725 | Error_Msg_N | |
726 | ("component size clase for& previously given", Nam); | |
727 | ||
728 | elsif Csize /= No_Uint then | |
729 | Check_Size (Expr, Component_Type (Btype), Csize, Biased); | |
730 | ||
731 | if Has_Aliased_Components (Btype) | |
732 | and then Csize < 32 | |
733 | and then Csize /= 8 | |
734 | and then Csize /= 16 | |
735 | then | |
736 | Error_Msg_N | |
737 | ("component size incorrect for aliased components", N); | |
738 | return; | |
739 | end if; | |
740 | ||
741 | -- For the biased case, build a declaration for a subtype | |
742 | -- that will be used to represent the biased subtype that | |
743 | -- reflects the biased representation of components. We need | |
744 | -- this subtype to get proper conversions on referencing | |
745 | -- elements of the array. | |
746 | ||
747 | if Biased then | |
748 | New_Ctyp := | |
749 | Make_Defining_Identifier (Loc, | |
750 | Chars => New_External_Name (Chars (U_Ent), 'C', 0, 'T')); | |
751 | ||
752 | Decl := | |
753 | Make_Subtype_Declaration (Loc, | |
754 | Defining_Identifier => New_Ctyp, | |
755 | Subtype_Indication => | |
756 | New_Occurrence_Of (Component_Type (Btype), Loc)); | |
757 | ||
758 | Set_Parent (Decl, N); | |
759 | Analyze (Decl, Suppress => All_Checks); | |
760 | ||
761 | Set_Has_Delayed_Freeze (New_Ctyp, False); | |
762 | Set_Esize (New_Ctyp, Csize); | |
763 | Set_RM_Size (New_Ctyp, Csize); | |
764 | Init_Alignment (New_Ctyp); | |
765 | Set_Has_Biased_Representation (New_Ctyp, True); | |
766 | Set_Is_Itype (New_Ctyp, True); | |
767 | Set_Associated_Node_For_Itype (New_Ctyp, U_Ent); | |
768 | ||
769 | Set_Component_Type (Btype, New_Ctyp); | |
770 | end if; | |
771 | ||
772 | Set_Component_Size (Btype, Csize); | |
773 | Set_Has_Component_Size_Clause (Btype, True); | |
774 | Set_Has_Non_Standard_Rep (Btype, True); | |
775 | end if; | |
776 | end Component_Size_Case; | |
777 | ||
778 | ------------------ | |
779 | -- External_Tag -- | |
780 | ------------------ | |
781 | ||
782 | when Attribute_External_Tag => External_Tag : | |
783 | begin | |
784 | if not Is_Tagged_Type (U_Ent) then | |
785 | Error_Msg_N ("should be a tagged type", Nam); | |
786 | end if; | |
787 | ||
788 | Analyze_And_Resolve (Expr, Standard_String); | |
789 | ||
790 | if not Is_Static_Expression (Expr) then | |
9dfe12ae | 791 | Flag_Non_Static_Expr |
792 | ("static string required for tag name!", Nam); | |
d6f39728 | 793 | end if; |
794 | ||
795 | Set_Has_External_Tag_Rep_Clause (U_Ent); | |
796 | end External_Tag; | |
797 | ||
798 | ----------- | |
799 | -- Input -- | |
800 | ----------- | |
801 | ||
9f373bb8 | 802 | when Attribute_Input => |
803 | Analyze_Stream_TSS_Definition (TSS_Stream_Input); | |
804 | Set_Has_Specified_Stream_Input (Ent); | |
d6f39728 | 805 | |
806 | ------------------- | |
807 | -- Machine_Radix -- | |
808 | ------------------- | |
809 | ||
810 | -- Machine radix attribute definition clause | |
811 | ||
812 | when Attribute_Machine_Radix => Machine_Radix : declare | |
813 | Radix : constant Uint := Static_Integer (Expr); | |
814 | ||
815 | begin | |
816 | if not Is_Decimal_Fixed_Point_Type (U_Ent) then | |
817 | Error_Msg_N ("decimal fixed-point type expected for &", Nam); | |
818 | ||
819 | elsif Has_Machine_Radix_Clause (U_Ent) then | |
820 | Error_Msg_Sloc := Sloc (Alignment_Clause (U_Ent)); | |
821 | Error_Msg_N ("machine radix clause previously given#", N); | |
822 | ||
823 | elsif Radix /= No_Uint then | |
824 | Set_Has_Machine_Radix_Clause (U_Ent); | |
825 | Set_Has_Non_Standard_Rep (Base_Type (U_Ent)); | |
826 | ||
827 | if Radix = 2 then | |
828 | null; | |
829 | elsif Radix = 10 then | |
830 | Set_Machine_Radix_10 (U_Ent); | |
831 | else | |
832 | Error_Msg_N ("machine radix value must be 2 or 10", Expr); | |
833 | end if; | |
834 | end if; | |
835 | end Machine_Radix; | |
836 | ||
837 | ----------------- | |
838 | -- Object_Size -- | |
839 | ----------------- | |
840 | ||
841 | -- Object_Size attribute definition clause | |
842 | ||
843 | when Attribute_Object_Size => Object_Size : declare | |
844 | Size : constant Uint := Static_Integer (Expr); | |
845 | Biased : Boolean; | |
846 | ||
847 | begin | |
848 | if not Is_Type (U_Ent) then | |
849 | Error_Msg_N ("Object_Size cannot be given for &", Nam); | |
850 | ||
851 | elsif Has_Object_Size_Clause (U_Ent) then | |
852 | Error_Msg_N ("Object_Size already given for &", Nam); | |
853 | ||
854 | else | |
855 | Check_Size (Expr, U_Ent, Size, Biased); | |
856 | ||
857 | if Size /= 8 | |
858 | and then | |
859 | Size /= 16 | |
860 | and then | |
861 | Size /= 32 | |
862 | and then | |
863 | UI_Mod (Size, 64) /= 0 | |
864 | then | |
865 | Error_Msg_N | |
866 | ("Object_Size must be 8, 16, 32, or multiple of 64", | |
867 | Expr); | |
868 | end if; | |
869 | ||
870 | Set_Esize (U_Ent, Size); | |
871 | Set_Has_Object_Size_Clause (U_Ent); | |
872 | Alignment_Check_For_Esize_Change (U_Ent); | |
873 | end if; | |
874 | end Object_Size; | |
875 | ||
876 | ------------ | |
877 | -- Output -- | |
878 | ------------ | |
879 | ||
9f373bb8 | 880 | when Attribute_Output => |
881 | Analyze_Stream_TSS_Definition (TSS_Stream_Output); | |
882 | Set_Has_Specified_Stream_Output (Ent); | |
d6f39728 | 883 | |
884 | ---------- | |
885 | -- Read -- | |
886 | ---------- | |
887 | ||
9f373bb8 | 888 | when Attribute_Read => |
889 | Analyze_Stream_TSS_Definition (TSS_Stream_Read); | |
890 | Set_Has_Specified_Stream_Read (Ent); | |
d6f39728 | 891 | |
892 | ---------- | |
893 | -- Size -- | |
894 | ---------- | |
895 | ||
896 | -- Size attribute definition clause | |
897 | ||
898 | when Attribute_Size => Size : declare | |
899 | Size : constant Uint := Static_Integer (Expr); | |
900 | Etyp : Entity_Id; | |
901 | Biased : Boolean; | |
902 | ||
903 | begin | |
904 | FOnly := True; | |
905 | ||
906 | if Has_Size_Clause (U_Ent) then | |
907 | Error_Msg_N ("size already given for &", Nam); | |
908 | ||
909 | elsif not Is_Type (U_Ent) | |
910 | and then Ekind (U_Ent) /= E_Variable | |
911 | and then Ekind (U_Ent) /= E_Constant | |
912 | then | |
913 | Error_Msg_N ("size cannot be given for &", Nam); | |
914 | ||
915 | elsif Is_Array_Type (U_Ent) | |
916 | and then not Is_Constrained (U_Ent) | |
917 | then | |
918 | Error_Msg_N | |
919 | ("size cannot be given for unconstrained array", Nam); | |
920 | ||
921 | elsif Size /= No_Uint then | |
d6f39728 | 922 | if Is_Type (U_Ent) then |
923 | Etyp := U_Ent; | |
924 | else | |
925 | Etyp := Etype (U_Ent); | |
926 | end if; | |
927 | ||
928 | -- Check size, note that Gigi is in charge of checking | |
929 | -- that the size of an array or record type is OK. Also | |
930 | -- we do not check the size in the ordinary fixed-point | |
931 | -- case, since it is too early to do so (there may be a | |
932 | -- subsequent small clause that affects the size). We can | |
933 | -- check the size if a small clause has already been given. | |
934 | ||
935 | if not Is_Ordinary_Fixed_Point_Type (U_Ent) | |
936 | or else Has_Small_Clause (U_Ent) | |
937 | then | |
938 | Check_Size (Expr, Etyp, Size, Biased); | |
939 | Set_Has_Biased_Representation (U_Ent, Biased); | |
940 | end if; | |
941 | ||
942 | -- For types set RM_Size and Esize if possible | |
943 | ||
944 | if Is_Type (U_Ent) then | |
945 | Set_RM_Size (U_Ent, Size); | |
946 | ||
947 | -- For scalar types, increase Object_Size to power of 2, | |
f15731c4 | 948 | -- but not less than a storage unit in any case (i.e., |
949 | -- normally this means it will be byte addressable). | |
d6f39728 | 950 | |
951 | if Is_Scalar_Type (U_Ent) then | |
f15731c4 | 952 | if Size <= System_Storage_Unit then |
953 | Init_Esize (U_Ent, System_Storage_Unit); | |
d6f39728 | 954 | elsif Size <= 16 then |
955 | Init_Esize (U_Ent, 16); | |
956 | elsif Size <= 32 then | |
957 | Init_Esize (U_Ent, 32); | |
958 | else | |
959 | Set_Esize (U_Ent, (Size + 63) / 64 * 64); | |
960 | end if; | |
961 | ||
962 | -- For all other types, object size = value size. The | |
963 | -- backend will adjust as needed. | |
964 | ||
965 | else | |
966 | Set_Esize (U_Ent, Size); | |
967 | end if; | |
968 | ||
969 | Alignment_Check_For_Esize_Change (U_Ent); | |
970 | ||
971 | -- For objects, set Esize only | |
972 | ||
973 | else | |
9dfe12ae | 974 | if Is_Elementary_Type (Etyp) then |
975 | if Size /= System_Storage_Unit | |
976 | and then | |
977 | Size /= System_Storage_Unit * 2 | |
978 | and then | |
979 | Size /= System_Storage_Unit * 4 | |
980 | and then | |
981 | Size /= System_Storage_Unit * 8 | |
982 | then | |
5c99c290 | 983 | Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit); |
87d5c1d0 | 984 | Error_Msg_Uint_2 := Error_Msg_Uint_1 * 8; |
9dfe12ae | 985 | Error_Msg_N |
5c99c290 | 986 | ("size for primitive object must be a power of 2" |
87d5c1d0 | 987 | & " in the range ^-^", N); |
9dfe12ae | 988 | end if; |
989 | end if; | |
990 | ||
d6f39728 | 991 | Set_Esize (U_Ent, Size); |
992 | end if; | |
993 | ||
994 | Set_Has_Size_Clause (U_Ent); | |
995 | end if; | |
996 | end Size; | |
997 | ||
998 | ----------- | |
999 | -- Small -- | |
1000 | ----------- | |
1001 | ||
1002 | -- Small attribute definition clause | |
1003 | ||
1004 | when Attribute_Small => Small : declare | |
1005 | Implicit_Base : constant Entity_Id := Base_Type (U_Ent); | |
1006 | Small : Ureal; | |
1007 | ||
1008 | begin | |
1009 | Analyze_And_Resolve (Expr, Any_Real); | |
1010 | ||
1011 | if Etype (Expr) = Any_Type then | |
1012 | return; | |
1013 | ||
1014 | elsif not Is_Static_Expression (Expr) then | |
9dfe12ae | 1015 | Flag_Non_Static_Expr |
1016 | ("small requires static expression!", Expr); | |
d6f39728 | 1017 | return; |
1018 | ||
1019 | else | |
1020 | Small := Expr_Value_R (Expr); | |
1021 | ||
1022 | if Small <= Ureal_0 then | |
1023 | Error_Msg_N ("small value must be greater than zero", Expr); | |
1024 | return; | |
1025 | end if; | |
1026 | ||
1027 | end if; | |
1028 | ||
1029 | if not Is_Ordinary_Fixed_Point_Type (U_Ent) then | |
1030 | Error_Msg_N | |
1031 | ("small requires an ordinary fixed point type", Nam); | |
1032 | ||
1033 | elsif Has_Small_Clause (U_Ent) then | |
1034 | Error_Msg_N ("small already given for &", Nam); | |
1035 | ||
1036 | elsif Small > Delta_Value (U_Ent) then | |
1037 | Error_Msg_N | |
1038 | ("small value must not be greater then delta value", Nam); | |
1039 | ||
1040 | else | |
1041 | Set_Small_Value (U_Ent, Small); | |
1042 | Set_Small_Value (Implicit_Base, Small); | |
1043 | Set_Has_Small_Clause (U_Ent); | |
1044 | Set_Has_Small_Clause (Implicit_Base); | |
1045 | Set_Has_Non_Standard_Rep (Implicit_Base); | |
1046 | end if; | |
1047 | end Small; | |
1048 | ||
1049 | ------------------ | |
1050 | -- Storage_Size -- | |
1051 | ------------------ | |
1052 | ||
1053 | -- Storage_Size attribute definition clause | |
1054 | ||
1055 | when Attribute_Storage_Size => Storage_Size : declare | |
1056 | Btype : constant Entity_Id := Base_Type (U_Ent); | |
1057 | Sprag : Node_Id; | |
1058 | ||
1059 | begin | |
1060 | if Is_Task_Type (U_Ent) then | |
e0521a36 | 1061 | Check_Restriction (No_Obsolescent_Features, N); |
1062 | ||
9dfe12ae | 1063 | if Warn_On_Obsolescent_Feature then |
1064 | Error_Msg_N | |
1065 | ("storage size clause for task is an " & | |
1066 | "obsolescent feature ('R'M 'J.9)?", N); | |
1067 | Error_Msg_N | |
d53a018a | 1068 | ("\use Storage_Size pragma instead?", N); |
9dfe12ae | 1069 | end if; |
1070 | ||
d6f39728 | 1071 | FOnly := True; |
1072 | end if; | |
1073 | ||
1074 | if not Is_Access_Type (U_Ent) | |
1075 | and then Ekind (U_Ent) /= E_Task_Type | |
1076 | then | |
1077 | Error_Msg_N ("storage size cannot be given for &", Nam); | |
1078 | ||
1079 | elsif Is_Access_Type (U_Ent) and Is_Derived_Type (U_Ent) then | |
1080 | Error_Msg_N | |
1081 | ("storage size cannot be given for a derived access type", | |
1082 | Nam); | |
1083 | ||
1084 | elsif Has_Storage_Size_Clause (Btype) then | |
1085 | Error_Msg_N ("storage size already given for &", Nam); | |
1086 | ||
1087 | else | |
1088 | Analyze_And_Resolve (Expr, Any_Integer); | |
1089 | ||
1090 | if Is_Access_Type (U_Ent) then | |
1091 | ||
1092 | if Present (Associated_Storage_Pool (U_Ent)) then | |
1093 | Error_Msg_N ("storage pool already given for &", Nam); | |
1094 | return; | |
1095 | end if; | |
1096 | ||
1097 | if Compile_Time_Known_Value (Expr) | |
1098 | and then Expr_Value (Expr) = 0 | |
1099 | then | |
1100 | Set_No_Pool_Assigned (Btype); | |
1101 | end if; | |
1102 | ||
1103 | else -- Is_Task_Type (U_Ent) | |
1104 | Sprag := Get_Rep_Pragma (Btype, Name_Storage_Size); | |
1105 | ||
1106 | if Present (Sprag) then | |
1107 | Error_Msg_Sloc := Sloc (Sprag); | |
1108 | Error_Msg_N | |
1109 | ("Storage_Size already specified#", Nam); | |
1110 | return; | |
1111 | end if; | |
1112 | end if; | |
1113 | ||
1114 | Set_Has_Storage_Size_Clause (Btype); | |
1115 | end if; | |
1116 | end Storage_Size; | |
1117 | ||
1118 | ------------------ | |
1119 | -- Storage_Pool -- | |
1120 | ------------------ | |
1121 | ||
1122 | -- Storage_Pool attribute definition clause | |
1123 | ||
1124 | when Attribute_Storage_Pool => Storage_Pool : declare | |
1125 | Pool : Entity_Id; | |
6b567c71 | 1126 | T : Entity_Id; |
d6f39728 | 1127 | |
1128 | begin | |
1129 | if Ekind (U_Ent) /= E_Access_Type | |
1130 | and then Ekind (U_Ent) /= E_General_Access_Type | |
1131 | then | |
1132 | Error_Msg_N ( | |
1133 | "storage pool can only be given for access types", Nam); | |
1134 | return; | |
1135 | ||
1136 | elsif Is_Derived_Type (U_Ent) then | |
1137 | Error_Msg_N | |
1138 | ("storage pool cannot be given for a derived access type", | |
1139 | Nam); | |
1140 | ||
1141 | elsif Has_Storage_Size_Clause (U_Ent) then | |
1142 | Error_Msg_N ("storage size already given for &", Nam); | |
1143 | return; | |
1144 | ||
1145 | elsif Present (Associated_Storage_Pool (U_Ent)) then | |
1146 | Error_Msg_N ("storage pool already given for &", Nam); | |
1147 | return; | |
1148 | end if; | |
1149 | ||
1150 | Analyze_And_Resolve | |
1151 | (Expr, Class_Wide_Type (RTE (RE_Root_Storage_Pool))); | |
1152 | ||
6b567c71 | 1153 | if Nkind (Expr) = N_Type_Conversion then |
1154 | T := Etype (Expression (Expr)); | |
1155 | else | |
1156 | T := Etype (Expr); | |
1157 | end if; | |
1158 | ||
1159 | -- The Stack_Bounded_Pool is used internally for implementing | |
1160 | -- access types with a Storage_Size. Since it only work | |
1161 | -- properly when used on one specific type, we need to check | |
1162 | -- that it is not highjacked improperly: | |
1163 | -- type T is access Integer; | |
1164 | -- for T'Storage_Size use n; | |
1165 | -- type Q is access Float; | |
1166 | -- for Q'Storage_Size use T'Storage_Size; -- incorrect | |
1167 | ||
1168 | if Base_Type (T) = RTE (RE_Stack_Bounded_Pool) then | |
1169 | Error_Msg_N ("non-sharable internal Pool", Expr); | |
1170 | return; | |
1171 | end if; | |
1172 | ||
d6f39728 | 1173 | -- If the argument is a name that is not an entity name, then |
1174 | -- we construct a renaming operation to define an entity of | |
1175 | -- type storage pool. | |
1176 | ||
1177 | if not Is_Entity_Name (Expr) | |
1178 | and then Is_Object_Reference (Expr) | |
1179 | then | |
1180 | Pool := | |
1181 | Make_Defining_Identifier (Loc, | |
1182 | Chars => New_Internal_Name ('P')); | |
1183 | ||
1184 | declare | |
1185 | Rnode : constant Node_Id := | |
1186 | Make_Object_Renaming_Declaration (Loc, | |
1187 | Defining_Identifier => Pool, | |
1188 | Subtype_Mark => | |
1189 | New_Occurrence_Of (Etype (Expr), Loc), | |
1190 | Name => Expr); | |
1191 | ||
1192 | begin | |
1193 | Insert_Before (N, Rnode); | |
1194 | Analyze (Rnode); | |
1195 | Set_Associated_Storage_Pool (U_Ent, Pool); | |
1196 | end; | |
1197 | ||
1198 | elsif Is_Entity_Name (Expr) then | |
1199 | Pool := Entity (Expr); | |
1200 | ||
1201 | -- If pool is a renamed object, get original one. This can | |
1202 | -- happen with an explicit renaming, and within instances. | |
1203 | ||
1204 | while Present (Renamed_Object (Pool)) | |
1205 | and then Is_Entity_Name (Renamed_Object (Pool)) | |
1206 | loop | |
1207 | Pool := Entity (Renamed_Object (Pool)); | |
1208 | end loop; | |
1209 | ||
1210 | if Present (Renamed_Object (Pool)) | |
1211 | and then Nkind (Renamed_Object (Pool)) = N_Type_Conversion | |
1212 | and then Is_Entity_Name (Expression (Renamed_Object (Pool))) | |
1213 | then | |
1214 | Pool := Entity (Expression (Renamed_Object (Pool))); | |
1215 | end if; | |
1216 | ||
6b567c71 | 1217 | Set_Associated_Storage_Pool (U_Ent, Pool); |
d6f39728 | 1218 | |
1219 | elsif Nkind (Expr) = N_Type_Conversion | |
1220 | and then Is_Entity_Name (Expression (Expr)) | |
1221 | and then Nkind (Original_Node (Expr)) = N_Attribute_Reference | |
1222 | then | |
1223 | Pool := Entity (Expression (Expr)); | |
6b567c71 | 1224 | Set_Associated_Storage_Pool (U_Ent, Pool); |
d6f39728 | 1225 | |
1226 | else | |
1227 | Error_Msg_N ("incorrect reference to a Storage Pool", Expr); | |
1228 | return; | |
1229 | end if; | |
1230 | end Storage_Pool; | |
1231 | ||
7189d17f | 1232 | ----------------- |
1233 | -- Stream_Size -- | |
1234 | ----------------- | |
1235 | ||
1236 | when Attribute_Stream_Size => Stream_Size : declare | |
1237 | Size : constant Uint := Static_Integer (Expr); | |
1238 | ||
1239 | begin | |
1240 | if Has_Stream_Size_Clause (U_Ent) then | |
1241 | Error_Msg_N ("Stream_Size already given for &", Nam); | |
1242 | ||
1243 | elsif Is_Elementary_Type (U_Ent) then | |
1244 | if Size /= System_Storage_Unit | |
1245 | and then | |
1246 | Size /= System_Storage_Unit * 2 | |
1247 | and then | |
1248 | Size /= System_Storage_Unit * 4 | |
1249 | and then | |
1250 | Size /= System_Storage_Unit * 8 | |
1251 | then | |
1252 | Error_Msg_Uint_1 := UI_From_Int (System_Storage_Unit); | |
1253 | Error_Msg_N | |
1254 | ("stream size for elementary type must be a" | |
1255 | & " power of 2 and at least ^", N); | |
1256 | ||
1257 | elsif RM_Size (U_Ent) > Size then | |
1258 | Error_Msg_Uint_1 := RM_Size (U_Ent); | |
1259 | Error_Msg_N | |
1260 | ("stream size for elementary type must be a" | |
1261 | & " power of 2 and at least ^", N); | |
1262 | end if; | |
1263 | ||
1264 | Set_Has_Stream_Size_Clause (U_Ent); | |
1265 | ||
1266 | else | |
1267 | Error_Msg_N ("Stream_Size cannot be given for &", Nam); | |
1268 | end if; | |
1269 | end Stream_Size; | |
1270 | ||
d6f39728 | 1271 | ---------------- |
1272 | -- Value_Size -- | |
1273 | ---------------- | |
1274 | ||
1275 | -- Value_Size attribute definition clause | |
1276 | ||
1277 | when Attribute_Value_Size => Value_Size : declare | |
1278 | Size : constant Uint := Static_Integer (Expr); | |
1279 | Biased : Boolean; | |
1280 | ||
1281 | begin | |
1282 | if not Is_Type (U_Ent) then | |
1283 | Error_Msg_N ("Value_Size cannot be given for &", Nam); | |
1284 | ||
1285 | elsif Present | |
1286 | (Get_Attribute_Definition_Clause | |
1287 | (U_Ent, Attribute_Value_Size)) | |
1288 | then | |
1289 | Error_Msg_N ("Value_Size already given for &", Nam); | |
1290 | ||
1291 | else | |
1292 | if Is_Elementary_Type (U_Ent) then | |
1293 | Check_Size (Expr, U_Ent, Size, Biased); | |
1294 | Set_Has_Biased_Representation (U_Ent, Biased); | |
1295 | end if; | |
1296 | ||
1297 | Set_RM_Size (U_Ent, Size); | |
1298 | end if; | |
1299 | end Value_Size; | |
1300 | ||
1301 | ----------- | |
1302 | -- Write -- | |
1303 | ----------- | |
1304 | ||
9f373bb8 | 1305 | when Attribute_Write => |
1306 | Analyze_Stream_TSS_Definition (TSS_Stream_Write); | |
1307 | Set_Has_Specified_Stream_Write (Ent); | |
d6f39728 | 1308 | |
1309 | -- All other attributes cannot be set | |
1310 | ||
1311 | when others => | |
1312 | Error_Msg_N | |
1313 | ("attribute& cannot be set with definition clause", N); | |
d6f39728 | 1314 | end case; |
1315 | ||
1316 | -- The test for the type being frozen must be performed after | |
1317 | -- any expression the clause has been analyzed since the expression | |
1318 | -- itself might cause freezing that makes the clause illegal. | |
1319 | ||
1320 | if Rep_Item_Too_Late (U_Ent, N, FOnly) then | |
1321 | return; | |
1322 | end if; | |
1323 | end Analyze_Attribute_Definition_Clause; | |
1324 | ||
1325 | ---------------------------- | |
1326 | -- Analyze_Code_Statement -- | |
1327 | ---------------------------- | |
1328 | ||
1329 | procedure Analyze_Code_Statement (N : Node_Id) is | |
1330 | HSS : constant Node_Id := Parent (N); | |
1331 | SBody : constant Node_Id := Parent (HSS); | |
1332 | Subp : constant Entity_Id := Current_Scope; | |
1333 | Stmt : Node_Id; | |
1334 | Decl : Node_Id; | |
1335 | StmtO : Node_Id; | |
1336 | DeclO : Node_Id; | |
1337 | ||
1338 | begin | |
1339 | -- Analyze and check we get right type, note that this implements the | |
1340 | -- requirement (RM 13.8(1)) that Machine_Code be with'ed, since that | |
1341 | -- is the only way that Asm_Insn could possibly be visible. | |
1342 | ||
1343 | Analyze_And_Resolve (Expression (N)); | |
1344 | ||
1345 | if Etype (Expression (N)) = Any_Type then | |
1346 | return; | |
1347 | elsif Etype (Expression (N)) /= RTE (RE_Asm_Insn) then | |
1348 | Error_Msg_N ("incorrect type for code statement", N); | |
1349 | return; | |
1350 | end if; | |
1351 | ||
1352 | -- Make sure we appear in the handled statement sequence of a | |
1353 | -- subprogram (RM 13.8(3)). | |
1354 | ||
1355 | if Nkind (HSS) /= N_Handled_Sequence_Of_Statements | |
1356 | or else Nkind (SBody) /= N_Subprogram_Body | |
1357 | then | |
1358 | Error_Msg_N | |
1359 | ("code statement can only appear in body of subprogram", N); | |
1360 | return; | |
1361 | end if; | |
1362 | ||
1363 | -- Do remaining checks (RM 13.8(3)) if not already done | |
1364 | ||
1365 | if not Is_Machine_Code_Subprogram (Subp) then | |
1366 | Set_Is_Machine_Code_Subprogram (Subp); | |
1367 | ||
1368 | -- No exception handlers allowed | |
1369 | ||
1370 | if Present (Exception_Handlers (HSS)) then | |
1371 | Error_Msg_N | |
1372 | ("exception handlers not permitted in machine code subprogram", | |
1373 | First (Exception_Handlers (HSS))); | |
1374 | end if; | |
1375 | ||
1376 | -- No declarations other than use clauses and pragmas (we allow | |
1377 | -- certain internally generated declarations as well). | |
1378 | ||
1379 | Decl := First (Declarations (SBody)); | |
1380 | while Present (Decl) loop | |
1381 | DeclO := Original_Node (Decl); | |
1382 | if Comes_From_Source (DeclO) | |
1383 | and then Nkind (DeclO) /= N_Pragma | |
1384 | and then Nkind (DeclO) /= N_Use_Package_Clause | |
1385 | and then Nkind (DeclO) /= N_Use_Type_Clause | |
1386 | and then Nkind (DeclO) /= N_Implicit_Label_Declaration | |
1387 | then | |
1388 | Error_Msg_N | |
1389 | ("this declaration not allowed in machine code subprogram", | |
1390 | DeclO); | |
1391 | end if; | |
1392 | ||
1393 | Next (Decl); | |
1394 | end loop; | |
1395 | ||
1396 | -- No statements other than code statements, pragmas, and labels. | |
1397 | -- Again we allow certain internally generated statements. | |
1398 | ||
1399 | Stmt := First (Statements (HSS)); | |
1400 | while Present (Stmt) loop | |
1401 | StmtO := Original_Node (Stmt); | |
1402 | if Comes_From_Source (StmtO) | |
1403 | and then Nkind (StmtO) /= N_Pragma | |
1404 | and then Nkind (StmtO) /= N_Label | |
1405 | and then Nkind (StmtO) /= N_Code_Statement | |
1406 | then | |
1407 | Error_Msg_N | |
1408 | ("this statement is not allowed in machine code subprogram", | |
1409 | StmtO); | |
1410 | end if; | |
1411 | ||
1412 | Next (Stmt); | |
1413 | end loop; | |
1414 | end if; | |
d6f39728 | 1415 | end Analyze_Code_Statement; |
1416 | ||
1417 | ----------------------------------------------- | |
1418 | -- Analyze_Enumeration_Representation_Clause -- | |
1419 | ----------------------------------------------- | |
1420 | ||
1421 | procedure Analyze_Enumeration_Representation_Clause (N : Node_Id) is | |
1422 | Ident : constant Node_Id := Identifier (N); | |
1423 | Aggr : constant Node_Id := Array_Aggregate (N); | |
1424 | Enumtype : Entity_Id; | |
1425 | Elit : Entity_Id; | |
1426 | Expr : Node_Id; | |
1427 | Assoc : Node_Id; | |
1428 | Choice : Node_Id; | |
1429 | Val : Uint; | |
1430 | Err : Boolean := False; | |
1431 | ||
1432 | Lo : constant Uint := Expr_Value (Type_Low_Bound (Universal_Integer)); | |
1433 | Hi : constant Uint := Expr_Value (Type_High_Bound (Universal_Integer)); | |
1434 | Min : Uint; | |
1435 | Max : Uint; | |
1436 | ||
1437 | begin | |
1438 | -- First some basic error checks | |
1439 | ||
1440 | Find_Type (Ident); | |
1441 | Enumtype := Entity (Ident); | |
1442 | ||
1443 | if Enumtype = Any_Type | |
1444 | or else Rep_Item_Too_Early (Enumtype, N) | |
1445 | then | |
1446 | return; | |
1447 | else | |
1448 | Enumtype := Underlying_Type (Enumtype); | |
1449 | end if; | |
1450 | ||
1451 | if not Is_Enumeration_Type (Enumtype) then | |
1452 | Error_Msg_NE | |
1453 | ("enumeration type required, found}", | |
1454 | Ident, First_Subtype (Enumtype)); | |
1455 | return; | |
1456 | end if; | |
1457 | ||
9dfe12ae | 1458 | -- Ignore rep clause on generic actual type. This will already have |
1459 | -- been flagged on the template as an error, and this is the safest | |
1460 | -- way to ensure we don't get a junk cascaded message in the instance. | |
1461 | ||
1462 | if Is_Generic_Actual_Type (Enumtype) then | |
1463 | return; | |
1464 | ||
1465 | -- Type must be in current scope | |
1466 | ||
1467 | elsif Scope (Enumtype) /= Current_Scope then | |
d6f39728 | 1468 | Error_Msg_N ("type must be declared in this scope", Ident); |
1469 | return; | |
1470 | ||
9dfe12ae | 1471 | -- Type must be a first subtype |
1472 | ||
d6f39728 | 1473 | elsif not Is_First_Subtype (Enumtype) then |
1474 | Error_Msg_N ("cannot give enumeration rep clause for subtype", N); | |
1475 | return; | |
1476 | ||
9dfe12ae | 1477 | -- Ignore duplicate rep clause |
1478 | ||
d6f39728 | 1479 | elsif Has_Enumeration_Rep_Clause (Enumtype) then |
1480 | Error_Msg_N ("duplicate enumeration rep clause ignored", N); | |
1481 | return; | |
1482 | ||
7189d17f | 1483 | -- Don't allow rep clause for standard [wide_[wide_]]character |
9dfe12ae | 1484 | |
d6f39728 | 1485 | elsif Root_Type (Enumtype) = Standard_Character |
1486 | or else Root_Type (Enumtype) = Standard_Wide_Character | |
7189d17f | 1487 | or else Root_Type (Enumtype) = Standard_Wide_Wide_Character |
d6f39728 | 1488 | then |
1489 | Error_Msg_N ("enumeration rep clause not allowed for this type", N); | |
9dfe12ae | 1490 | return; |
1491 | ||
d9125581 | 1492 | -- Check that the expression is a proper aggregate (no parentheses) |
1493 | ||
1494 | elsif Paren_Count (Aggr) /= 0 then | |
1495 | Error_Msg | |
1496 | ("extra parentheses surrounding aggregate not allowed", | |
1497 | First_Sloc (Aggr)); | |
1498 | return; | |
1499 | ||
9dfe12ae | 1500 | -- All tests passed, so set rep clause in place |
d6f39728 | 1501 | |
1502 | else | |
1503 | Set_Has_Enumeration_Rep_Clause (Enumtype); | |
1504 | Set_Has_Enumeration_Rep_Clause (Base_Type (Enumtype)); | |
1505 | end if; | |
1506 | ||
1507 | -- Now we process the aggregate. Note that we don't use the normal | |
1508 | -- aggregate code for this purpose, because we don't want any of the | |
1509 | -- normal expansion activities, and a number of special semantic | |
1510 | -- rules apply (including the component type being any integer type) | |
1511 | ||
d6f39728 | 1512 | Elit := First_Literal (Enumtype); |
1513 | ||
1514 | -- First the positional entries if any | |
1515 | ||
1516 | if Present (Expressions (Aggr)) then | |
1517 | Expr := First (Expressions (Aggr)); | |
1518 | while Present (Expr) loop | |
1519 | if No (Elit) then | |
1520 | Error_Msg_N ("too many entries in aggregate", Expr); | |
1521 | return; | |
1522 | end if; | |
1523 | ||
1524 | Val := Static_Integer (Expr); | |
1525 | ||
d9125581 | 1526 | -- Err signals that we found some incorrect entries processing |
1527 | -- the list. The final checks for completeness and ordering are | |
1528 | -- skipped in this case. | |
1529 | ||
d6f39728 | 1530 | if Val = No_Uint then |
1531 | Err := True; | |
d6f39728 | 1532 | elsif Val < Lo or else Hi < Val then |
1533 | Error_Msg_N ("value outside permitted range", Expr); | |
1534 | Err := True; | |
1535 | end if; | |
1536 | ||
1537 | Set_Enumeration_Rep (Elit, Val); | |
1538 | Set_Enumeration_Rep_Expr (Elit, Expr); | |
1539 | Next (Expr); | |
1540 | Next (Elit); | |
1541 | end loop; | |
1542 | end if; | |
1543 | ||
1544 | -- Now process the named entries if present | |
1545 | ||
1546 | if Present (Component_Associations (Aggr)) then | |
1547 | Assoc := First (Component_Associations (Aggr)); | |
1548 | while Present (Assoc) loop | |
1549 | Choice := First (Choices (Assoc)); | |
1550 | ||
1551 | if Present (Next (Choice)) then | |
1552 | Error_Msg_N | |
1553 | ("multiple choice not allowed here", Next (Choice)); | |
1554 | Err := True; | |
1555 | end if; | |
1556 | ||
1557 | if Nkind (Choice) = N_Others_Choice then | |
1558 | Error_Msg_N ("others choice not allowed here", Choice); | |
1559 | Err := True; | |
1560 | ||
1561 | elsif Nkind (Choice) = N_Range then | |
1562 | -- ??? should allow zero/one element range here | |
1563 | Error_Msg_N ("range not allowed here", Choice); | |
1564 | Err := True; | |
1565 | ||
1566 | else | |
1567 | Analyze_And_Resolve (Choice, Enumtype); | |
1568 | ||
1569 | if Is_Entity_Name (Choice) | |
1570 | and then Is_Type (Entity (Choice)) | |
1571 | then | |
1572 | Error_Msg_N ("subtype name not allowed here", Choice); | |
1573 | Err := True; | |
1574 | -- ??? should allow static subtype with zero/one entry | |
1575 | ||
1576 | elsif Etype (Choice) = Base_Type (Enumtype) then | |
1577 | if not Is_Static_Expression (Choice) then | |
9dfe12ae | 1578 | Flag_Non_Static_Expr |
1579 | ("non-static expression used for choice!", Choice); | |
d6f39728 | 1580 | Err := True; |
1581 | ||
1582 | else | |
1583 | Elit := Expr_Value_E (Choice); | |
1584 | ||
1585 | if Present (Enumeration_Rep_Expr (Elit)) then | |
1586 | Error_Msg_Sloc := Sloc (Enumeration_Rep_Expr (Elit)); | |
1587 | Error_Msg_NE | |
1588 | ("representation for& previously given#", | |
1589 | Choice, Elit); | |
1590 | Err := True; | |
1591 | end if; | |
1592 | ||
1593 | Set_Enumeration_Rep_Expr (Elit, Choice); | |
1594 | ||
1595 | Expr := Expression (Assoc); | |
1596 | Val := Static_Integer (Expr); | |
1597 | ||
1598 | if Val = No_Uint then | |
1599 | Err := True; | |
1600 | ||
1601 | elsif Val < Lo or else Hi < Val then | |
1602 | Error_Msg_N ("value outside permitted range", Expr); | |
1603 | Err := True; | |
1604 | end if; | |
1605 | ||
1606 | Set_Enumeration_Rep (Elit, Val); | |
1607 | end if; | |
1608 | end if; | |
1609 | end if; | |
1610 | ||
1611 | Next (Assoc); | |
1612 | end loop; | |
1613 | end if; | |
1614 | ||
1615 | -- Aggregate is fully processed. Now we check that a full set of | |
1616 | -- representations was given, and that they are in range and in order. | |
1617 | -- These checks are only done if no other errors occurred. | |
1618 | ||
1619 | if not Err then | |
1620 | Min := No_Uint; | |
1621 | Max := No_Uint; | |
1622 | ||
1623 | Elit := First_Literal (Enumtype); | |
1624 | while Present (Elit) loop | |
1625 | if No (Enumeration_Rep_Expr (Elit)) then | |
1626 | Error_Msg_NE ("missing representation for&!", N, Elit); | |
1627 | ||
1628 | else | |
1629 | Val := Enumeration_Rep (Elit); | |
1630 | ||
1631 | if Min = No_Uint then | |
1632 | Min := Val; | |
1633 | end if; | |
1634 | ||
1635 | if Val /= No_Uint then | |
1636 | if Max /= No_Uint and then Val <= Max then | |
1637 | Error_Msg_NE | |
1638 | ("enumeration value for& not ordered!", | |
1639 | Enumeration_Rep_Expr (Elit), Elit); | |
1640 | end if; | |
1641 | ||
1642 | Max := Val; | |
1643 | end if; | |
1644 | ||
1645 | -- If there is at least one literal whose representation | |
1646 | -- is not equal to the Pos value, then note that this | |
1647 | -- enumeration type has a non-standard representation. | |
1648 | ||
1649 | if Val /= Enumeration_Pos (Elit) then | |
1650 | Set_Has_Non_Standard_Rep (Base_Type (Enumtype)); | |
1651 | end if; | |
1652 | end if; | |
1653 | ||
1654 | Next (Elit); | |
1655 | end loop; | |
1656 | ||
1657 | -- Now set proper size information | |
1658 | ||
1659 | declare | |
1660 | Minsize : Uint := UI_From_Int (Minimum_Size (Enumtype)); | |
1661 | ||
1662 | begin | |
1663 | if Has_Size_Clause (Enumtype) then | |
1664 | if Esize (Enumtype) >= Minsize then | |
1665 | null; | |
1666 | ||
1667 | else | |
1668 | Minsize := | |
1669 | UI_From_Int (Minimum_Size (Enumtype, Biased => True)); | |
1670 | ||
1671 | if Esize (Enumtype) < Minsize then | |
1672 | Error_Msg_N ("previously given size is too small", N); | |
1673 | ||
1674 | else | |
1675 | Set_Has_Biased_Representation (Enumtype); | |
1676 | end if; | |
1677 | end if; | |
1678 | ||
1679 | else | |
1680 | Set_RM_Size (Enumtype, Minsize); | |
1681 | Set_Enum_Esize (Enumtype); | |
1682 | end if; | |
1683 | ||
1684 | Set_RM_Size (Base_Type (Enumtype), RM_Size (Enumtype)); | |
1685 | Set_Esize (Base_Type (Enumtype), Esize (Enumtype)); | |
1686 | Set_Alignment (Base_Type (Enumtype), Alignment (Enumtype)); | |
1687 | end; | |
1688 | end if; | |
1689 | ||
1690 | -- We repeat the too late test in case it froze itself! | |
1691 | ||
1692 | if Rep_Item_Too_Late (Enumtype, N) then | |
1693 | null; | |
1694 | end if; | |
d6f39728 | 1695 | end Analyze_Enumeration_Representation_Clause; |
1696 | ||
1697 | ---------------------------- | |
1698 | -- Analyze_Free_Statement -- | |
1699 | ---------------------------- | |
1700 | ||
1701 | procedure Analyze_Free_Statement (N : Node_Id) is | |
1702 | begin | |
1703 | Analyze (Expression (N)); | |
1704 | end Analyze_Free_Statement; | |
1705 | ||
1706 | ------------------------------------------ | |
1707 | -- Analyze_Record_Representation_Clause -- | |
1708 | ------------------------------------------ | |
1709 | ||
1710 | procedure Analyze_Record_Representation_Clause (N : Node_Id) is | |
1711 | Loc : constant Source_Ptr := Sloc (N); | |
1712 | Ident : constant Node_Id := Identifier (N); | |
1713 | Rectype : Entity_Id; | |
1714 | Fent : Entity_Id; | |
1715 | CC : Node_Id; | |
1716 | Posit : Uint; | |
1717 | Fbit : Uint; | |
1718 | Lbit : Uint; | |
1719 | Hbit : Uint := Uint_0; | |
1720 | Comp : Entity_Id; | |
1721 | Ocomp : Entity_Id; | |
1722 | Biased : Boolean; | |
1723 | ||
1724 | Max_Bit_So_Far : Uint; | |
ea61a7ea | 1725 | -- Records the maximum bit position so far. If all field positions |
d6f39728 | 1726 | -- are monotonically increasing, then we can skip the circuit for |
1727 | -- checking for overlap, since no overlap is possible. | |
1728 | ||
1729 | Overlap_Check_Required : Boolean; | |
1730 | -- Used to keep track of whether or not an overlap check is required | |
1731 | ||
1732 | Ccount : Natural := 0; | |
1733 | -- Number of component clauses in record rep clause | |
1734 | ||
639e37b0 | 1735 | CR_Pragma : Node_Id := Empty; |
1736 | -- Points to N_Pragma node if Complete_Representation pragma present | |
1737 | ||
d6f39728 | 1738 | begin |
1739 | Find_Type (Ident); | |
1740 | Rectype := Entity (Ident); | |
1741 | ||
1742 | if Rectype = Any_Type | |
1743 | or else Rep_Item_Too_Early (Rectype, N) | |
1744 | then | |
1745 | return; | |
1746 | else | |
1747 | Rectype := Underlying_Type (Rectype); | |
1748 | end if; | |
1749 | ||
1750 | -- First some basic error checks | |
1751 | ||
1752 | if not Is_Record_Type (Rectype) then | |
1753 | Error_Msg_NE | |
1754 | ("record type required, found}", Ident, First_Subtype (Rectype)); | |
1755 | return; | |
1756 | ||
1757 | elsif Is_Unchecked_Union (Rectype) then | |
1758 | Error_Msg_N | |
1759 | ("record rep clause not allowed for Unchecked_Union", N); | |
1760 | ||
1761 | elsif Scope (Rectype) /= Current_Scope then | |
1762 | Error_Msg_N ("type must be declared in this scope", N); | |
1763 | return; | |
1764 | ||
1765 | elsif not Is_First_Subtype (Rectype) then | |
1766 | Error_Msg_N ("cannot give record rep clause for subtype", N); | |
1767 | return; | |
1768 | ||
1769 | elsif Has_Record_Rep_Clause (Rectype) then | |
1770 | Error_Msg_N ("duplicate record rep clause ignored", N); | |
1771 | return; | |
1772 | ||
1773 | elsif Rep_Item_Too_Late (Rectype, N) then | |
1774 | return; | |
1775 | end if; | |
1776 | ||
1777 | if Present (Mod_Clause (N)) then | |
1778 | declare | |
1779 | Loc : constant Source_Ptr := Sloc (N); | |
1780 | M : constant Node_Id := Mod_Clause (N); | |
1781 | P : constant List_Id := Pragmas_Before (M); | |
d6f39728 | 1782 | AtM_Nod : Node_Id; |
1783 | ||
9dfe12ae | 1784 | Mod_Val : Uint; |
1785 | pragma Warnings (Off, Mod_Val); | |
1786 | ||
d6f39728 | 1787 | begin |
e0521a36 | 1788 | Check_Restriction (No_Obsolescent_Features, Mod_Clause (N)); |
1789 | ||
9dfe12ae | 1790 | if Warn_On_Obsolescent_Feature then |
1791 | Error_Msg_N | |
1792 | ("mod clause is an obsolescent feature ('R'M 'J.8)?", N); | |
1793 | Error_Msg_N | |
d53a018a | 1794 | ("\use alignment attribute definition clause instead?", N); |
9dfe12ae | 1795 | end if; |
1796 | ||
d6f39728 | 1797 | if Present (P) then |
1798 | Analyze_List (P); | |
1799 | end if; | |
1800 | ||
9dfe12ae | 1801 | -- In ASIS_Mode mode, expansion is disabled, but we must |
d6f39728 | 1802 | -- convert the Mod clause into an alignment clause anyway, so |
1803 | -- that the back-end can compute and back-annotate properly the | |
1804 | -- size and alignment of types that may include this record. | |
1805 | ||
1806 | if Operating_Mode = Check_Semantics | |
9dfe12ae | 1807 | and then ASIS_Mode |
d6f39728 | 1808 | then |
1809 | AtM_Nod := | |
1810 | Make_Attribute_Definition_Clause (Loc, | |
1811 | Name => New_Reference_To (Base_Type (Rectype), Loc), | |
1812 | Chars => Name_Alignment, | |
1813 | Expression => Relocate_Node (Expression (M))); | |
1814 | ||
1815 | Set_From_At_Mod (AtM_Nod); | |
1816 | Insert_After (N, AtM_Nod); | |
1817 | Mod_Val := Get_Alignment_Value (Expression (AtM_Nod)); | |
1818 | Set_Mod_Clause (N, Empty); | |
1819 | ||
1820 | else | |
1821 | -- Get the alignment value to perform error checking | |
1822 | ||
1823 | Mod_Val := Get_Alignment_Value (Expression (M)); | |
1824 | ||
1825 | end if; | |
1826 | end; | |
1827 | end if; | |
1828 | ||
1829 | -- Clear any existing component clauses for the type (this happens | |
1830 | -- with derived types, where we are now overriding the original) | |
1831 | ||
1832 | Fent := First_Entity (Rectype); | |
1833 | ||
1834 | Comp := Fent; | |
1835 | while Present (Comp) loop | |
1836 | if Ekind (Comp) = E_Component | |
1837 | or else Ekind (Comp) = E_Discriminant | |
1838 | then | |
1839 | Set_Component_Clause (Comp, Empty); | |
1840 | end if; | |
1841 | ||
1842 | Next_Entity (Comp); | |
1843 | end loop; | |
1844 | ||
1845 | -- All done if no component clauses | |
1846 | ||
1847 | CC := First (Component_Clauses (N)); | |
1848 | ||
1849 | if No (CC) then | |
1850 | return; | |
1851 | end if; | |
1852 | ||
1853 | -- If a tag is present, then create a component clause that places | |
1854 | -- it at the start of the record (otherwise gigi may place it after | |
1855 | -- other fields that have rep clauses). | |
1856 | ||
1857 | if Nkind (Fent) = N_Defining_Identifier | |
1858 | and then Chars (Fent) = Name_uTag | |
1859 | then | |
1860 | Set_Component_Bit_Offset (Fent, Uint_0); | |
1861 | Set_Normalized_Position (Fent, Uint_0); | |
1862 | Set_Normalized_First_Bit (Fent, Uint_0); | |
1863 | Set_Normalized_Position_Max (Fent, Uint_0); | |
1864 | Init_Esize (Fent, System_Address_Size); | |
1865 | ||
1866 | Set_Component_Clause (Fent, | |
1867 | Make_Component_Clause (Loc, | |
1868 | Component_Name => | |
1869 | Make_Identifier (Loc, | |
1870 | Chars => Name_uTag), | |
1871 | ||
1872 | Position => | |
1873 | Make_Integer_Literal (Loc, | |
1874 | Intval => Uint_0), | |
1875 | ||
1876 | First_Bit => | |
1877 | Make_Integer_Literal (Loc, | |
1878 | Intval => Uint_0), | |
1879 | ||
1880 | Last_Bit => | |
1881 | Make_Integer_Literal (Loc, | |
1882 | UI_From_Int (System_Address_Size)))); | |
1883 | ||
1884 | Ccount := Ccount + 1; | |
1885 | end if; | |
1886 | ||
f15731c4 | 1887 | -- A representation like this applies to the base type |
d6f39728 | 1888 | |
1889 | Set_Has_Record_Rep_Clause (Base_Type (Rectype)); | |
1890 | Set_Has_Non_Standard_Rep (Base_Type (Rectype)); | |
1891 | Set_Has_Specified_Layout (Base_Type (Rectype)); | |
1892 | ||
1893 | Max_Bit_So_Far := Uint_Minus_1; | |
1894 | Overlap_Check_Required := False; | |
1895 | ||
1896 | -- Process the component clauses | |
1897 | ||
1898 | while Present (CC) loop | |
1899 | ||
639e37b0 | 1900 | -- Pragma |
d6f39728 | 1901 | |
1902 | if Nkind (CC) = N_Pragma then | |
1903 | Analyze (CC); | |
1904 | ||
639e37b0 | 1905 | -- The only pragma of interest is Complete_Representation |
1906 | ||
1907 | if Chars (CC) = Name_Complete_Representation then | |
1908 | CR_Pragma := CC; | |
1909 | end if; | |
1910 | ||
d6f39728 | 1911 | -- Processing for real component clause |
1912 | ||
1913 | else | |
1914 | Ccount := Ccount + 1; | |
1915 | Posit := Static_Integer (Position (CC)); | |
1916 | Fbit := Static_Integer (First_Bit (CC)); | |
1917 | Lbit := Static_Integer (Last_Bit (CC)); | |
1918 | ||
1919 | if Posit /= No_Uint | |
1920 | and then Fbit /= No_Uint | |
1921 | and then Lbit /= No_Uint | |
1922 | then | |
1923 | if Posit < 0 then | |
1924 | Error_Msg_N | |
1925 | ("position cannot be negative", Position (CC)); | |
1926 | ||
1927 | elsif Fbit < 0 then | |
1928 | Error_Msg_N | |
1929 | ("first bit cannot be negative", First_Bit (CC)); | |
1930 | ||
1931 | -- Values look OK, so find the corresponding record component | |
1932 | -- Even though the syntax allows an attribute reference for | |
1933 | -- implementation-defined components, GNAT does not allow the | |
1934 | -- tag to get an explicit position. | |
1935 | ||
1936 | elsif Nkind (Component_Name (CC)) = N_Attribute_Reference then | |
d6f39728 | 1937 | if Attribute_Name (Component_Name (CC)) = Name_Tag then |
1938 | Error_Msg_N ("position of tag cannot be specified", CC); | |
1939 | else | |
1940 | Error_Msg_N ("illegal component name", CC); | |
1941 | end if; | |
1942 | ||
1943 | else | |
1944 | Comp := First_Entity (Rectype); | |
1945 | while Present (Comp) loop | |
1946 | exit when Chars (Comp) = Chars (Component_Name (CC)); | |
1947 | Next_Entity (Comp); | |
1948 | end loop; | |
1949 | ||
1950 | if No (Comp) then | |
1951 | ||
1952 | -- Maybe component of base type that is absent from | |
1953 | -- statically constrained first subtype. | |
1954 | ||
1955 | Comp := First_Entity (Base_Type (Rectype)); | |
1956 | while Present (Comp) loop | |
1957 | exit when Chars (Comp) = Chars (Component_Name (CC)); | |
1958 | Next_Entity (Comp); | |
1959 | end loop; | |
1960 | end if; | |
1961 | ||
1962 | if No (Comp) then | |
1963 | Error_Msg_N | |
1964 | ("component clause is for non-existent field", CC); | |
1965 | ||
1966 | elsif Present (Component_Clause (Comp)) then | |
1967 | Error_Msg_Sloc := Sloc (Component_Clause (Comp)); | |
1968 | Error_Msg_N | |
1969 | ("component clause previously given#", CC); | |
1970 | ||
1971 | else | |
2866d595 | 1972 | -- Update Fbit and Lbit to the actual bit number |
d6f39728 | 1973 | |
1974 | Fbit := Fbit + UI_From_Int (SSU) * Posit; | |
1975 | Lbit := Lbit + UI_From_Int (SSU) * Posit; | |
1976 | ||
1977 | if Fbit <= Max_Bit_So_Far then | |
1978 | Overlap_Check_Required := True; | |
1979 | else | |
1980 | Max_Bit_So_Far := Lbit; | |
1981 | end if; | |
1982 | ||
1983 | if Has_Size_Clause (Rectype) | |
1984 | and then Esize (Rectype) <= Lbit | |
1985 | then | |
1986 | Error_Msg_N | |
1987 | ("bit number out of range of specified size", | |
1988 | Last_Bit (CC)); | |
1989 | else | |
1990 | Set_Component_Clause (Comp, CC); | |
1991 | Set_Component_Bit_Offset (Comp, Fbit); | |
1992 | Set_Esize (Comp, 1 + (Lbit - Fbit)); | |
1993 | Set_Normalized_First_Bit (Comp, Fbit mod SSU); | |
1994 | Set_Normalized_Position (Comp, Fbit / SSU); | |
1995 | ||
1996 | Set_Normalized_Position_Max | |
1997 | (Fent, Normalized_Position (Fent)); | |
1998 | ||
1999 | if Is_Tagged_Type (Rectype) | |
2000 | and then Fbit < System_Address_Size | |
2001 | then | |
2002 | Error_Msg_NE | |
2003 | ("component overlaps tag field of&", | |
2004 | CC, Rectype); | |
2005 | end if; | |
2006 | ||
ea61a7ea | 2007 | -- This information is also set in the corresponding |
2008 | -- component of the base type, found by accessing the | |
2009 | -- Original_Record_Component link if it is present. | |
d6f39728 | 2010 | |
2011 | Ocomp := Original_Record_Component (Comp); | |
2012 | ||
2013 | if Hbit < Lbit then | |
2014 | Hbit := Lbit; | |
2015 | end if; | |
2016 | ||
2017 | Check_Size | |
2018 | (Component_Name (CC), | |
2019 | Etype (Comp), | |
2020 | Esize (Comp), | |
2021 | Biased); | |
2022 | ||
2023 | Set_Has_Biased_Representation (Comp, Biased); | |
2024 | ||
2025 | if Present (Ocomp) then | |
2026 | Set_Component_Clause (Ocomp, CC); | |
2027 | Set_Component_Bit_Offset (Ocomp, Fbit); | |
2028 | Set_Normalized_First_Bit (Ocomp, Fbit mod SSU); | |
2029 | Set_Normalized_Position (Ocomp, Fbit / SSU); | |
2030 | Set_Esize (Ocomp, 1 + (Lbit - Fbit)); | |
2031 | ||
2032 | Set_Normalized_Position_Max | |
2033 | (Ocomp, Normalized_Position (Ocomp)); | |
2034 | ||
2035 | Set_Has_Biased_Representation | |
2036 | (Ocomp, Has_Biased_Representation (Comp)); | |
2037 | end if; | |
2038 | ||
2039 | if Esize (Comp) < 0 then | |
2040 | Error_Msg_N ("component size is negative", CC); | |
2041 | end if; | |
2042 | end if; | |
2043 | end if; | |
2044 | end if; | |
2045 | end if; | |
2046 | end if; | |
2047 | ||
2048 | Next (CC); | |
2049 | end loop; | |
2050 | ||
2051 | -- Now that we have processed all the component clauses, check for | |
2052 | -- overlap. We have to leave this till last, since the components | |
2053 | -- can appear in any arbitrary order in the representation clause. | |
2054 | ||
2055 | -- We do not need this check if all specified ranges were monotonic, | |
2056 | -- as recorded by Overlap_Check_Required being False at this stage. | |
2057 | ||
2058 | -- This first section checks if there are any overlapping entries | |
2059 | -- at all. It does this by sorting all entries and then seeing if | |
2060 | -- there are any overlaps. If there are none, then that is decisive, | |
2061 | -- but if there are overlaps, they may still be OK (they may result | |
2062 | -- from fields in different variants). | |
2063 | ||
2064 | if Overlap_Check_Required then | |
2065 | Overlap_Check1 : declare | |
2066 | ||
2067 | OC_Fbit : array (0 .. Ccount) of Uint; | |
2068 | -- First-bit values for component clauses, the value is the | |
2069 | -- offset of the first bit of the field from start of record. | |
2070 | -- The zero entry is for use in sorting. | |
2071 | ||
2072 | OC_Lbit : array (0 .. Ccount) of Uint; | |
2073 | -- Last-bit values for component clauses, the value is the | |
2074 | -- offset of the last bit of the field from start of record. | |
2075 | -- The zero entry is for use in sorting. | |
2076 | ||
2077 | OC_Count : Natural := 0; | |
2078 | -- Count of entries in OC_Fbit and OC_Lbit | |
2079 | ||
2080 | function OC_Lt (Op1, Op2 : Natural) return Boolean; | |
2081 | -- Compare routine for Sort (See GNAT.Heap_Sort_A) | |
2082 | ||
2083 | procedure OC_Move (From : Natural; To : Natural); | |
2084 | -- Move routine for Sort (see GNAT.Heap_Sort_A) | |
2085 | ||
2086 | function OC_Lt (Op1, Op2 : Natural) return Boolean is | |
2087 | begin | |
2088 | return OC_Fbit (Op1) < OC_Fbit (Op2); | |
2089 | end OC_Lt; | |
2090 | ||
2091 | procedure OC_Move (From : Natural; To : Natural) is | |
2092 | begin | |
2093 | OC_Fbit (To) := OC_Fbit (From); | |
2094 | OC_Lbit (To) := OC_Lbit (From); | |
2095 | end OC_Move; | |
2096 | ||
2097 | begin | |
2098 | CC := First (Component_Clauses (N)); | |
2099 | while Present (CC) loop | |
2100 | if Nkind (CC) /= N_Pragma then | |
2101 | Posit := Static_Integer (Position (CC)); | |
2102 | Fbit := Static_Integer (First_Bit (CC)); | |
2103 | Lbit := Static_Integer (Last_Bit (CC)); | |
2104 | ||
2105 | if Posit /= No_Uint | |
2106 | and then Fbit /= No_Uint | |
2107 | and then Lbit /= No_Uint | |
2108 | then | |
2109 | OC_Count := OC_Count + 1; | |
2110 | Posit := Posit * SSU; | |
2111 | OC_Fbit (OC_Count) := Fbit + Posit; | |
2112 | OC_Lbit (OC_Count) := Lbit + Posit; | |
2113 | end if; | |
2114 | end if; | |
2115 | ||
2116 | Next (CC); | |
2117 | end loop; | |
2118 | ||
2119 | Sort | |
2120 | (OC_Count, | |
2121 | OC_Move'Unrestricted_Access, | |
2122 | OC_Lt'Unrestricted_Access); | |
2123 | ||
2124 | Overlap_Check_Required := False; | |
2125 | for J in 1 .. OC_Count - 1 loop | |
2126 | if OC_Lbit (J) >= OC_Fbit (J + 1) then | |
2127 | Overlap_Check_Required := True; | |
2128 | exit; | |
2129 | end if; | |
2130 | end loop; | |
2131 | end Overlap_Check1; | |
2132 | end if; | |
2133 | ||
2134 | -- If Overlap_Check_Required is still True, then we have to do | |
2135 | -- the full scale overlap check, since we have at least two fields | |
2136 | -- that do overlap, and we need to know if that is OK since they | |
2137 | -- are in the same variant, or whether we have a definite problem | |
2138 | ||
2139 | if Overlap_Check_Required then | |
2140 | Overlap_Check2 : declare | |
2141 | C1_Ent, C2_Ent : Entity_Id; | |
2142 | -- Entities of components being checked for overlap | |
2143 | ||
2144 | Clist : Node_Id; | |
2145 | -- Component_List node whose Component_Items are being checked | |
2146 | ||
2147 | Citem : Node_Id; | |
2148 | -- Component declaration for component being checked | |
2149 | ||
2150 | begin | |
2151 | C1_Ent := First_Entity (Base_Type (Rectype)); | |
2152 | ||
2153 | -- Loop through all components in record. For each component check | |
2154 | -- for overlap with any of the preceding elements on the component | |
2155 | -- list containing the component, and also, if the component is in | |
2156 | -- a variant, check against components outside the case structure. | |
2157 | -- This latter test is repeated recursively up the variant tree. | |
2158 | ||
2159 | Main_Component_Loop : while Present (C1_Ent) loop | |
2160 | if Ekind (C1_Ent) /= E_Component | |
2161 | and then Ekind (C1_Ent) /= E_Discriminant | |
2162 | then | |
2163 | goto Continue_Main_Component_Loop; | |
2164 | end if; | |
2165 | ||
2166 | -- Skip overlap check if entity has no declaration node. This | |
2167 | -- happens with discriminants in constrained derived types. | |
2168 | -- Probably we are missing some checks as a result, but that | |
2169 | -- does not seem terribly serious ??? | |
2170 | ||
2171 | if No (Declaration_Node (C1_Ent)) then | |
2172 | goto Continue_Main_Component_Loop; | |
2173 | end if; | |
2174 | ||
2175 | Clist := Parent (List_Containing (Declaration_Node (C1_Ent))); | |
2176 | ||
2177 | -- Loop through component lists that need checking. Check the | |
2178 | -- current component list and all lists in variants above us. | |
2179 | ||
2180 | Component_List_Loop : loop | |
2181 | ||
2182 | -- If derived type definition, go to full declaration | |
2183 | -- If at outer level, check discriminants if there are any | |
2184 | ||
2185 | if Nkind (Clist) = N_Derived_Type_Definition then | |
2186 | Clist := Parent (Clist); | |
2187 | end if; | |
2188 | ||
2189 | -- Outer level of record definition, check discriminants | |
2190 | ||
2191 | if Nkind (Clist) = N_Full_Type_Declaration | |
2192 | or else Nkind (Clist) = N_Private_Type_Declaration | |
2193 | then | |
2194 | if Has_Discriminants (Defining_Identifier (Clist)) then | |
2195 | C2_Ent := | |
2196 | First_Discriminant (Defining_Identifier (Clist)); | |
2197 | ||
2198 | while Present (C2_Ent) loop | |
2199 | exit when C1_Ent = C2_Ent; | |
2200 | Check_Component_Overlap (C1_Ent, C2_Ent); | |
2201 | Next_Discriminant (C2_Ent); | |
2202 | end loop; | |
2203 | end if; | |
2204 | ||
2205 | -- Record extension case | |
2206 | ||
2207 | elsif Nkind (Clist) = N_Derived_Type_Definition then | |
2208 | Clist := Empty; | |
2209 | ||
2210 | -- Otherwise check one component list | |
2211 | ||
2212 | else | |
2213 | Citem := First (Component_Items (Clist)); | |
2214 | ||
2215 | while Present (Citem) loop | |
2216 | if Nkind (Citem) = N_Component_Declaration then | |
2217 | C2_Ent := Defining_Identifier (Citem); | |
2218 | exit when C1_Ent = C2_Ent; | |
2219 | Check_Component_Overlap (C1_Ent, C2_Ent); | |
2220 | end if; | |
2221 | ||
2222 | Next (Citem); | |
2223 | end loop; | |
2224 | end if; | |
2225 | ||
2226 | -- Check for variants above us (the parent of the Clist can | |
2227 | -- be a variant, in which case its parent is a variant part, | |
2228 | -- and the parent of the variant part is a component list | |
2229 | -- whose components must all be checked against the current | |
2230 | -- component for overlap. | |
2231 | ||
2232 | if Nkind (Parent (Clist)) = N_Variant then | |
2233 | Clist := Parent (Parent (Parent (Clist))); | |
2234 | ||
2235 | -- Check for possible discriminant part in record, this is | |
2236 | -- treated essentially as another level in the recursion. | |
2237 | -- For this case we have the parent of the component list | |
2238 | -- is the record definition, and its parent is the full | |
2239 | -- type declaration which contains the discriminant | |
2240 | -- specifications. | |
2241 | ||
2242 | elsif Nkind (Parent (Clist)) = N_Record_Definition then | |
2243 | Clist := Parent (Parent ((Clist))); | |
2244 | ||
2245 | -- If neither of these two cases, we are at the top of | |
2246 | -- the tree | |
2247 | ||
2248 | else | |
2249 | exit Component_List_Loop; | |
2250 | end if; | |
2251 | end loop Component_List_Loop; | |
2252 | ||
2253 | <<Continue_Main_Component_Loop>> | |
2254 | Next_Entity (C1_Ent); | |
2255 | ||
2256 | end loop Main_Component_Loop; | |
2257 | end Overlap_Check2; | |
2258 | end if; | |
2259 | ||
2260 | -- For records that have component clauses for all components, and | |
2261 | -- whose size is less than or equal to 32, we need to know the size | |
2262 | -- in the front end to activate possible packed array processing | |
2263 | -- where the component type is a record. | |
2264 | ||
2265 | -- At this stage Hbit + 1 represents the first unused bit from all | |
2266 | -- the component clauses processed, so if the component clauses are | |
2267 | -- complete, then this is the length of the record. | |
2268 | ||
2269 | -- For records longer than System.Storage_Unit, and for those where | |
2270 | -- not all components have component clauses, the back end determines | |
2271 | -- the length (it may for example be appopriate to round up the size | |
2272 | -- to some convenient boundary, based on alignment considerations etc). | |
2273 | ||
2274 | if Unknown_RM_Size (Rectype) | |
2275 | and then Hbit + 1 <= 32 | |
2276 | then | |
2277 | -- Nothing to do if at least one component with no component clause | |
2278 | ||
2279 | Comp := First_Entity (Rectype); | |
2280 | while Present (Comp) loop | |
2281 | if Ekind (Comp) = E_Component | |
2282 | or else Ekind (Comp) = E_Discriminant | |
2283 | then | |
639e37b0 | 2284 | exit when No (Component_Clause (Comp)); |
d6f39728 | 2285 | end if; |
2286 | ||
2287 | Next_Entity (Comp); | |
2288 | end loop; | |
2289 | ||
2290 | -- If we fall out of loop, all components have component clauses | |
2291 | -- and so we can set the size to the maximum value. | |
2292 | ||
639e37b0 | 2293 | if No (Comp) then |
2294 | Set_RM_Size (Rectype, Hbit + 1); | |
2295 | end if; | |
2296 | end if; | |
2297 | ||
2298 | -- Check missing components if Complete_Representation pragma appeared | |
2299 | ||
2300 | if Present (CR_Pragma) then | |
2301 | Comp := First_Entity (Rectype); | |
2302 | while Present (Comp) loop | |
2303 | if Ekind (Comp) = E_Component | |
2304 | or else | |
2305 | Ekind (Comp) = E_Discriminant | |
2306 | then | |
2307 | if No (Component_Clause (Comp)) then | |
2308 | Error_Msg_NE | |
2309 | ("missing component clause for &", CR_Pragma, Comp); | |
2310 | end if; | |
2311 | end if; | |
2312 | ||
2313 | Next_Entity (Comp); | |
2314 | end loop; | |
d6f39728 | 2315 | end if; |
d6f39728 | 2316 | end Analyze_Record_Representation_Clause; |
2317 | ||
d6f39728 | 2318 | ----------------------------- |
2319 | -- Check_Component_Overlap -- | |
2320 | ----------------------------- | |
2321 | ||
2322 | procedure Check_Component_Overlap (C1_Ent, C2_Ent : Entity_Id) is | |
2323 | begin | |
2324 | if Present (Component_Clause (C1_Ent)) | |
2325 | and then Present (Component_Clause (C2_Ent)) | |
2326 | then | |
2327 | -- Exclude odd case where we have two tag fields in the same | |
2328 | -- record, both at location zero. This seems a bit strange, | |
2329 | -- but it seems to happen in some circumstances ??? | |
2330 | ||
2331 | if Chars (C1_Ent) = Name_uTag | |
2332 | and then Chars (C2_Ent) = Name_uTag | |
2333 | then | |
2334 | return; | |
2335 | end if; | |
2336 | ||
2337 | -- Here we check if the two fields overlap | |
2338 | ||
2339 | declare | |
2340 | S1 : constant Uint := Component_Bit_Offset (C1_Ent); | |
2341 | S2 : constant Uint := Component_Bit_Offset (C2_Ent); | |
2342 | E1 : constant Uint := S1 + Esize (C1_Ent); | |
2343 | E2 : constant Uint := S2 + Esize (C2_Ent); | |
2344 | ||
2345 | begin | |
2346 | if E2 <= S1 or else E1 <= S2 then | |
2347 | null; | |
2348 | else | |
2349 | Error_Msg_Node_2 := | |
2350 | Component_Name (Component_Clause (C2_Ent)); | |
2351 | Error_Msg_Sloc := Sloc (Error_Msg_Node_2); | |
2352 | Error_Msg_Node_1 := | |
2353 | Component_Name (Component_Clause (C1_Ent)); | |
2354 | Error_Msg_N | |
2355 | ("component& overlaps & #", | |
2356 | Component_Name (Component_Clause (C1_Ent))); | |
2357 | end if; | |
2358 | end; | |
2359 | end if; | |
2360 | end Check_Component_Overlap; | |
2361 | ||
2362 | ----------------------------------- | |
2363 | -- Check_Constant_Address_Clause -- | |
2364 | ----------------------------------- | |
2365 | ||
2366 | procedure Check_Constant_Address_Clause | |
2367 | (Expr : Node_Id; | |
2368 | U_Ent : Entity_Id) | |
2369 | is | |
2370 | procedure Check_At_Constant_Address (Nod : Node_Id); | |
2371 | -- Checks that the given node N represents a name whose 'Address | |
2372 | -- is constant (in the same sense as OK_Constant_Address_Clause, | |
2373 | -- i.e. the address value is the same at the point of declaration | |
2374 | -- of U_Ent and at the time of elaboration of the address clause. | |
2375 | ||
2376 | procedure Check_Expr_Constants (Nod : Node_Id); | |
2377 | -- Checks that Nod meets the requirements for a constant address | |
2378 | -- clause in the sense of the enclosing procedure. | |
2379 | ||
2380 | procedure Check_List_Constants (Lst : List_Id); | |
2381 | -- Check that all elements of list Lst meet the requirements for a | |
2382 | -- constant address clause in the sense of the enclosing procedure. | |
2383 | ||
2384 | ------------------------------- | |
2385 | -- Check_At_Constant_Address -- | |
2386 | ------------------------------- | |
2387 | ||
2388 | procedure Check_At_Constant_Address (Nod : Node_Id) is | |
2389 | begin | |
2390 | if Is_Entity_Name (Nod) then | |
2391 | if Present (Address_Clause (Entity ((Nod)))) then | |
2392 | Error_Msg_NE | |
2393 | ("invalid address clause for initialized object &!", | |
2394 | Nod, U_Ent); | |
2395 | Error_Msg_NE | |
2396 | ("address for& cannot" & | |
2397 | " depend on another address clause! ('R'M 13.1(22))!", | |
2398 | Nod, U_Ent); | |
2399 | ||
2400 | elsif In_Same_Source_Unit (Entity (Nod), U_Ent) | |
2401 | and then Sloc (U_Ent) < Sloc (Entity (Nod)) | |
2402 | then | |
2403 | Error_Msg_NE | |
2404 | ("invalid address clause for initialized object &!", | |
2405 | Nod, U_Ent); | |
2406 | Error_Msg_Name_1 := Chars (Entity (Nod)); | |
2407 | Error_Msg_Name_2 := Chars (U_Ent); | |
2408 | Error_Msg_N | |
2409 | ("\% must be defined before % ('R'M 13.1(22))!", | |
2410 | Nod); | |
2411 | end if; | |
2412 | ||
2413 | elsif Nkind (Nod) = N_Selected_Component then | |
2414 | declare | |
2415 | T : constant Entity_Id := Etype (Prefix (Nod)); | |
2416 | ||
2417 | begin | |
2418 | if (Is_Record_Type (T) | |
2419 | and then Has_Discriminants (T)) | |
2420 | or else | |
2421 | (Is_Access_Type (T) | |
2422 | and then Is_Record_Type (Designated_Type (T)) | |
2423 | and then Has_Discriminants (Designated_Type (T))) | |
2424 | then | |
2425 | Error_Msg_NE | |
2426 | ("invalid address clause for initialized object &!", | |
2427 | Nod, U_Ent); | |
2428 | Error_Msg_N | |
2429 | ("\address cannot depend on component" & | |
2430 | " of discriminated record ('R'M 13.1(22))!", | |
2431 | Nod); | |
2432 | else | |
2433 | Check_At_Constant_Address (Prefix (Nod)); | |
2434 | end if; | |
2435 | end; | |
2436 | ||
2437 | elsif Nkind (Nod) = N_Indexed_Component then | |
2438 | Check_At_Constant_Address (Prefix (Nod)); | |
2439 | Check_List_Constants (Expressions (Nod)); | |
2440 | ||
2441 | else | |
2442 | Check_Expr_Constants (Nod); | |
2443 | end if; | |
2444 | end Check_At_Constant_Address; | |
2445 | ||
2446 | -------------------------- | |
2447 | -- Check_Expr_Constants -- | |
2448 | -------------------------- | |
2449 | ||
2450 | procedure Check_Expr_Constants (Nod : Node_Id) is | |
e7b2d6bc | 2451 | Loc_U_Ent : constant Source_Ptr := Sloc (U_Ent); |
2452 | Ent : Entity_Id := Empty; | |
2453 | ||
d6f39728 | 2454 | begin |
2455 | if Nkind (Nod) in N_Has_Etype | |
2456 | and then Etype (Nod) = Any_Type | |
2457 | then | |
2458 | return; | |
2459 | end if; | |
2460 | ||
2461 | case Nkind (Nod) is | |
2462 | when N_Empty | N_Error => | |
2463 | return; | |
2464 | ||
2465 | when N_Identifier | N_Expanded_Name => | |
e7b2d6bc | 2466 | Ent := Entity (Nod); |
9dfe12ae | 2467 | |
2468 | -- We need to look at the original node if it is different | |
2469 | -- from the node, since we may have rewritten things and | |
2470 | -- substituted an identifier representing the rewrite. | |
2471 | ||
2472 | if Original_Node (Nod) /= Nod then | |
2473 | Check_Expr_Constants (Original_Node (Nod)); | |
2474 | ||
2475 | -- If the node is an object declaration without initial | |
2476 | -- value, some code has been expanded, and the expression | |
2477 | -- is not constant, even if the constituents might be | |
2478 | -- acceptable, as in A'Address + offset. | |
2479 | ||
e7b2d6bc | 2480 | if Ekind (Ent) = E_Variable |
2481 | and then Nkind (Declaration_Node (Ent)) | |
9dfe12ae | 2482 | = N_Object_Declaration |
2483 | and then | |
e7b2d6bc | 2484 | No (Expression (Declaration_Node (Ent))) |
2485 | then | |
2486 | Error_Msg_NE | |
2487 | ("invalid address clause for initialized object &!", | |
2488 | Nod, U_Ent); | |
2489 | ||
2490 | -- If entity is constant, it may be the result of expanding | |
2491 | -- a check. We must verify that its declaration appears | |
2492 | -- before the object in question, else we also reject the | |
2493 | -- address clause. | |
2494 | ||
2495 | elsif Ekind (Ent) = E_Constant | |
2496 | and then In_Same_Source_Unit (Ent, U_Ent) | |
2497 | and then Sloc (Ent) > Loc_U_Ent | |
9dfe12ae | 2498 | then |
2499 | Error_Msg_NE | |
2500 | ("invalid address clause for initialized object &!", | |
2501 | Nod, U_Ent); | |
2502 | end if; | |
e7b2d6bc | 2503 | |
9dfe12ae | 2504 | return; |
2505 | end if; | |
2506 | ||
2866d595 | 2507 | -- Otherwise look at the identifier and see if it is OK |
9dfe12ae | 2508 | |
e7b2d6bc | 2509 | if Ekind (Ent) = E_Named_Integer |
2510 | or else | |
2511 | Ekind (Ent) = E_Named_Real | |
2512 | or else | |
2513 | Is_Type (Ent) | |
2514 | then | |
2515 | return; | |
d6f39728 | 2516 | |
e7b2d6bc | 2517 | elsif |
2518 | Ekind (Ent) = E_Constant | |
2519 | or else | |
2520 | Ekind (Ent) = E_In_Parameter | |
2521 | then | |
2522 | -- This is the case where we must have Ent defined | |
2523 | -- before U_Ent. Clearly if they are in different | |
2524 | -- units this requirement is met since the unit | |
2525 | -- containing Ent is already processed. | |
d6f39728 | 2526 | |
e7b2d6bc | 2527 | if not In_Same_Source_Unit (Ent, U_Ent) then |
2528 | return; | |
d6f39728 | 2529 | |
e7b2d6bc | 2530 | -- Otherwise location of Ent must be before the |
2531 | -- location of U_Ent, that's what prior defined means. | |
d6f39728 | 2532 | |
e7b2d6bc | 2533 | elsif Sloc (Ent) < Loc_U_Ent then |
2534 | return; | |
d6f39728 | 2535 | |
2536 | else | |
2537 | Error_Msg_NE | |
2538 | ("invalid address clause for initialized object &!", | |
2539 | Nod, U_Ent); | |
e7b2d6bc | 2540 | Error_Msg_Name_1 := Chars (Ent); |
2541 | Error_Msg_Name_2 := Chars (U_Ent); | |
2542 | Error_Msg_N | |
2543 | ("\% must be defined before % ('R'M 13.1(22))!", | |
2544 | Nod); | |
2545 | end if; | |
9dfe12ae | 2546 | |
e7b2d6bc | 2547 | elsif Nkind (Original_Node (Nod)) = N_Function_Call then |
2548 | Check_Expr_Constants (Original_Node (Nod)); | |
2549 | ||
2550 | else | |
2551 | Error_Msg_NE | |
2552 | ("invalid address clause for initialized object &!", | |
2553 | Nod, U_Ent); | |
2554 | ||
2555 | if Comes_From_Source (Ent) then | |
2556 | Error_Msg_Name_1 := Chars (Ent); | |
2557 | Error_Msg_N | |
2558 | ("\reference to variable% not allowed" | |
2559 | & " ('R'M 13.1(22))!", Nod); | |
2560 | else | |
2561 | Error_Msg_N | |
2562 | ("non-static expression not allowed" | |
2563 | & " ('R'M 13.1(22))!", Nod); | |
d6f39728 | 2564 | end if; |
e7b2d6bc | 2565 | end if; |
d6f39728 | 2566 | |
93735cb8 | 2567 | when N_Integer_Literal => |
2568 | ||
2569 | -- If this is a rewritten unchecked conversion, in a system | |
2570 | -- where Address is an integer type, always use the base type | |
2571 | -- for a literal value. This is user-friendly and prevents | |
2572 | -- order-of-elaboration issues with instances of unchecked | |
2573 | -- conversion. | |
2574 | ||
2575 | if Nkind (Original_Node (Nod)) = N_Function_Call then | |
2576 | Set_Etype (Nod, Base_Type (Etype (Nod))); | |
2577 | end if; | |
2578 | ||
2579 | when N_Real_Literal | | |
d6f39728 | 2580 | N_String_Literal | |
2581 | N_Character_Literal => | |
2582 | return; | |
2583 | ||
2584 | when N_Range => | |
2585 | Check_Expr_Constants (Low_Bound (Nod)); | |
2586 | Check_Expr_Constants (High_Bound (Nod)); | |
2587 | ||
2588 | when N_Explicit_Dereference => | |
2589 | Check_Expr_Constants (Prefix (Nod)); | |
2590 | ||
2591 | when N_Indexed_Component => | |
2592 | Check_Expr_Constants (Prefix (Nod)); | |
2593 | Check_List_Constants (Expressions (Nod)); | |
2594 | ||
2595 | when N_Slice => | |
2596 | Check_Expr_Constants (Prefix (Nod)); | |
2597 | Check_Expr_Constants (Discrete_Range (Nod)); | |
2598 | ||
2599 | when N_Selected_Component => | |
2600 | Check_Expr_Constants (Prefix (Nod)); | |
2601 | ||
2602 | when N_Attribute_Reference => | |
9dfe12ae | 2603 | if Attribute_Name (Nod) = Name_Address |
2604 | or else | |
2605 | Attribute_Name (Nod) = Name_Access | |
d6f39728 | 2606 | or else |
9dfe12ae | 2607 | Attribute_Name (Nod) = Name_Unchecked_Access |
d6f39728 | 2608 | or else |
9dfe12ae | 2609 | Attribute_Name (Nod) = Name_Unrestricted_Access |
d6f39728 | 2610 | then |
2611 | Check_At_Constant_Address (Prefix (Nod)); | |
2612 | ||
2613 | else | |
2614 | Check_Expr_Constants (Prefix (Nod)); | |
2615 | Check_List_Constants (Expressions (Nod)); | |
2616 | end if; | |
2617 | ||
2618 | when N_Aggregate => | |
2619 | Check_List_Constants (Component_Associations (Nod)); | |
2620 | Check_List_Constants (Expressions (Nod)); | |
2621 | ||
2622 | when N_Component_Association => | |
2623 | Check_Expr_Constants (Expression (Nod)); | |
2624 | ||
2625 | when N_Extension_Aggregate => | |
2626 | Check_Expr_Constants (Ancestor_Part (Nod)); | |
2627 | Check_List_Constants (Component_Associations (Nod)); | |
2628 | Check_List_Constants (Expressions (Nod)); | |
2629 | ||
2630 | when N_Null => | |
2631 | return; | |
2632 | ||
2633 | when N_Binary_Op | N_And_Then | N_Or_Else | N_In | N_Not_In => | |
2634 | Check_Expr_Constants (Left_Opnd (Nod)); | |
2635 | Check_Expr_Constants (Right_Opnd (Nod)); | |
2636 | ||
2637 | when N_Unary_Op => | |
2638 | Check_Expr_Constants (Right_Opnd (Nod)); | |
2639 | ||
2640 | when N_Type_Conversion | | |
2641 | N_Qualified_Expression | | |
2642 | N_Allocator => | |
2643 | Check_Expr_Constants (Expression (Nod)); | |
2644 | ||
2645 | when N_Unchecked_Type_Conversion => | |
2646 | Check_Expr_Constants (Expression (Nod)); | |
2647 | ||
2648 | -- If this is a rewritten unchecked conversion, subtypes | |
2649 | -- in this node are those created within the instance. | |
2650 | -- To avoid order of elaboration issues, replace them | |
2651 | -- with their base types. Note that address clauses can | |
2652 | -- cause order of elaboration problems because they are | |
2653 | -- elaborated by the back-end at the point of definition, | |
2654 | -- and may mention entities declared in between (as long | |
2655 | -- as everything is static). It is user-friendly to allow | |
2656 | -- unchecked conversions in this context. | |
2657 | ||
2658 | if Nkind (Original_Node (Nod)) = N_Function_Call then | |
2659 | Set_Etype (Expression (Nod), | |
2660 | Base_Type (Etype (Expression (Nod)))); | |
2661 | Set_Etype (Nod, Base_Type (Etype (Nod))); | |
2662 | end if; | |
2663 | ||
2664 | when N_Function_Call => | |
2665 | if not Is_Pure (Entity (Name (Nod))) then | |
2666 | Error_Msg_NE | |
2667 | ("invalid address clause for initialized object &!", | |
2668 | Nod, U_Ent); | |
2669 | ||
2670 | Error_Msg_NE | |
2671 | ("\function & is not pure ('R'M 13.1(22))!", | |
2672 | Nod, Entity (Name (Nod))); | |
2673 | ||
2674 | else | |
2675 | Check_List_Constants (Parameter_Associations (Nod)); | |
2676 | end if; | |
2677 | ||
2678 | when N_Parameter_Association => | |
2679 | Check_Expr_Constants (Explicit_Actual_Parameter (Nod)); | |
2680 | ||
2681 | when others => | |
2682 | Error_Msg_NE | |
2683 | ("invalid address clause for initialized object &!", | |
2684 | Nod, U_Ent); | |
2685 | Error_Msg_NE | |
2686 | ("\must be constant defined before& ('R'M 13.1(22))!", | |
2687 | Nod, U_Ent); | |
2688 | end case; | |
2689 | end Check_Expr_Constants; | |
2690 | ||
2691 | -------------------------- | |
2692 | -- Check_List_Constants -- | |
2693 | -------------------------- | |
2694 | ||
2695 | procedure Check_List_Constants (Lst : List_Id) is | |
2696 | Nod1 : Node_Id; | |
2697 | ||
2698 | begin | |
2699 | if Present (Lst) then | |
2700 | Nod1 := First (Lst); | |
2701 | while Present (Nod1) loop | |
2702 | Check_Expr_Constants (Nod1); | |
2703 | Next (Nod1); | |
2704 | end loop; | |
2705 | end if; | |
2706 | end Check_List_Constants; | |
2707 | ||
2708 | -- Start of processing for Check_Constant_Address_Clause | |
2709 | ||
2710 | begin | |
2711 | Check_Expr_Constants (Expr); | |
2712 | end Check_Constant_Address_Clause; | |
2713 | ||
2714 | ---------------- | |
2715 | -- Check_Size -- | |
2716 | ---------------- | |
2717 | ||
2718 | procedure Check_Size | |
2719 | (N : Node_Id; | |
2720 | T : Entity_Id; | |
2721 | Siz : Uint; | |
2722 | Biased : out Boolean) | |
2723 | is | |
2724 | UT : constant Entity_Id := Underlying_Type (T); | |
2725 | M : Uint; | |
2726 | ||
2727 | begin | |
2728 | Biased := False; | |
2729 | ||
ea61a7ea | 2730 | -- Dismiss cases for generic types or types with previous errors |
d6f39728 | 2731 | |
2732 | if No (UT) | |
2733 | or else UT = Any_Type | |
2734 | or else Is_Generic_Type (UT) | |
2735 | or else Is_Generic_Type (Root_Type (UT)) | |
d6f39728 | 2736 | then |
2737 | return; | |
2738 | ||
ea61a7ea | 2739 | -- Check case of bit packed array |
2740 | ||
2741 | elsif Is_Array_Type (UT) | |
2742 | and then Known_Static_Component_Size (UT) | |
2743 | and then Is_Bit_Packed_Array (UT) | |
2744 | then | |
2745 | declare | |
2746 | Asiz : Uint; | |
2747 | Indx : Node_Id; | |
2748 | Ityp : Entity_Id; | |
2749 | ||
2750 | begin | |
2751 | Asiz := Component_Size (UT); | |
2752 | Indx := First_Index (UT); | |
2753 | loop | |
2754 | Ityp := Etype (Indx); | |
2755 | ||
2756 | -- If non-static bound, then we are not in the business of | |
2757 | -- trying to check the length, and indeed an error will be | |
2758 | -- issued elsewhere, since sizes of non-static array types | |
2759 | -- cannot be set implicitly or explicitly. | |
2760 | ||
2761 | if not Is_Static_Subtype (Ityp) then | |
2762 | return; | |
2763 | end if; | |
2764 | ||
2765 | -- Otherwise accumulate next dimension | |
2766 | ||
2767 | Asiz := Asiz * (Expr_Value (Type_High_Bound (Ityp)) - | |
2768 | Expr_Value (Type_Low_Bound (Ityp)) + | |
2769 | Uint_1); | |
2770 | ||
2771 | Next_Index (Indx); | |
2772 | exit when No (Indx); | |
2773 | end loop; | |
2774 | ||
2775 | if Asiz <= Siz then | |
2776 | return; | |
2777 | else | |
2778 | Error_Msg_Uint_1 := Asiz; | |
2779 | Error_Msg_NE | |
2780 | ("size for& too small, minimum allowed is ^", N, T); | |
37cb33b0 | 2781 | Set_Esize (T, Asiz); |
2782 | Set_RM_Size (T, Asiz); | |
ea61a7ea | 2783 | end if; |
2784 | end; | |
2785 | ||
2786 | -- All other composite types are ignored | |
2787 | ||
2788 | elsif Is_Composite_Type (UT) then | |
2789 | return; | |
2790 | ||
d6f39728 | 2791 | -- For fixed-point types, don't check minimum if type is not frozen, |
ea61a7ea | 2792 | -- since we don't know all the characteristics of the type that can |
2793 | -- affect the size (e.g. a specified small) till freeze time. | |
d6f39728 | 2794 | |
2795 | elsif Is_Fixed_Point_Type (UT) | |
2796 | and then not Is_Frozen (UT) | |
2797 | then | |
2798 | null; | |
2799 | ||
2800 | -- Cases for which a minimum check is required | |
2801 | ||
2802 | else | |
ea61a7ea | 2803 | -- Ignore if specified size is correct for the type |
2804 | ||
2805 | if Known_Esize (UT) and then Siz = Esize (UT) then | |
2806 | return; | |
2807 | end if; | |
2808 | ||
2809 | -- Otherwise get minimum size | |
2810 | ||
d6f39728 | 2811 | M := UI_From_Int (Minimum_Size (UT)); |
2812 | ||
2813 | if Siz < M then | |
2814 | ||
2815 | -- Size is less than minimum size, but one possibility remains | |
2816 | -- that we can manage with the new size if we bias the type | |
2817 | ||
2818 | M := UI_From_Int (Minimum_Size (UT, Biased => True)); | |
2819 | ||
2820 | if Siz < M then | |
2821 | Error_Msg_Uint_1 := M; | |
2822 | Error_Msg_NE | |
2823 | ("size for& too small, minimum allowed is ^", N, T); | |
37cb33b0 | 2824 | Set_Esize (T, M); |
2825 | Set_RM_Size (T, M); | |
d6f39728 | 2826 | else |
2827 | Biased := True; | |
2828 | end if; | |
2829 | end if; | |
2830 | end if; | |
2831 | end Check_Size; | |
2832 | ||
2833 | ------------------------- | |
2834 | -- Get_Alignment_Value -- | |
2835 | ------------------------- | |
2836 | ||
2837 | function Get_Alignment_Value (Expr : Node_Id) return Uint is | |
2838 | Align : constant Uint := Static_Integer (Expr); | |
2839 | ||
2840 | begin | |
2841 | if Align = No_Uint then | |
2842 | return No_Uint; | |
2843 | ||
2844 | elsif Align <= 0 then | |
2845 | Error_Msg_N ("alignment value must be positive", Expr); | |
2846 | return No_Uint; | |
2847 | ||
2848 | else | |
2849 | for J in Int range 0 .. 64 loop | |
2850 | declare | |
2851 | M : constant Uint := Uint_2 ** J; | |
2852 | ||
2853 | begin | |
2854 | exit when M = Align; | |
2855 | ||
2856 | if M > Align then | |
2857 | Error_Msg_N | |
2858 | ("alignment value must be power of 2", Expr); | |
2859 | return No_Uint; | |
2860 | end if; | |
2861 | end; | |
2862 | end loop; | |
2863 | ||
2864 | return Align; | |
2865 | end if; | |
2866 | end Get_Alignment_Value; | |
2867 | ||
d6f39728 | 2868 | ---------------- |
2869 | -- Initialize -- | |
2870 | ---------------- | |
2871 | ||
2872 | procedure Initialize is | |
2873 | begin | |
2874 | Unchecked_Conversions.Init; | |
2875 | end Initialize; | |
2876 | ||
2877 | ------------------------- | |
2878 | -- Is_Operational_Item -- | |
2879 | ------------------------- | |
2880 | ||
2881 | function Is_Operational_Item (N : Node_Id) return Boolean is | |
2882 | begin | |
2883 | if Nkind (N) /= N_Attribute_Definition_Clause then | |
2884 | return False; | |
2885 | else | |
2886 | declare | |
2887 | Id : constant Attribute_Id := Get_Attribute_Id (Chars (N)); | |
2888 | ||
2889 | begin | |
2890 | return Id = Attribute_Input | |
2891 | or else Id = Attribute_Output | |
2892 | or else Id = Attribute_Read | |
f15731c4 | 2893 | or else Id = Attribute_Write |
2894 | or else Id = Attribute_External_Tag; | |
d6f39728 | 2895 | end; |
2896 | end if; | |
2897 | end Is_Operational_Item; | |
2898 | ||
9dfe12ae | 2899 | -------------------------------------- |
2900 | -- Mark_Aliased_Address_As_Volatile -- | |
2901 | -------------------------------------- | |
2902 | ||
2903 | procedure Mark_Aliased_Address_As_Volatile (N : Node_Id) is | |
2904 | Ent : constant Entity_Id := Address_Aliased_Entity (N); | |
2905 | ||
2906 | begin | |
2907 | if Present (Ent) then | |
2908 | Set_Treat_As_Volatile (Ent); | |
2909 | end if; | |
2910 | end Mark_Aliased_Address_As_Volatile; | |
2911 | ||
d6f39728 | 2912 | ------------------ |
2913 | -- Minimum_Size -- | |
2914 | ------------------ | |
2915 | ||
2916 | function Minimum_Size | |
2917 | (T : Entity_Id; | |
d5b349fa | 2918 | Biased : Boolean := False) return Nat |
d6f39728 | 2919 | is |
2920 | Lo : Uint := No_Uint; | |
2921 | Hi : Uint := No_Uint; | |
2922 | LoR : Ureal := No_Ureal; | |
2923 | HiR : Ureal := No_Ureal; | |
2924 | LoSet : Boolean := False; | |
2925 | HiSet : Boolean := False; | |
2926 | B : Uint; | |
2927 | S : Nat; | |
2928 | Ancest : Entity_Id; | |
f15731c4 | 2929 | R_Typ : constant Entity_Id := Root_Type (T); |
d6f39728 | 2930 | |
2931 | begin | |
2932 | -- If bad type, return 0 | |
2933 | ||
2934 | if T = Any_Type then | |
2935 | return 0; | |
2936 | ||
2937 | -- For generic types, just return zero. There cannot be any legitimate | |
2938 | -- need to know such a size, but this routine may be called with a | |
2939 | -- generic type as part of normal processing. | |
2940 | ||
f15731c4 | 2941 | elsif Is_Generic_Type (R_Typ) |
2942 | or else R_Typ = Any_Type | |
2943 | then | |
d6f39728 | 2944 | return 0; |
2945 | ||
93735cb8 | 2946 | -- Access types. Normally an access type cannot have a size smaller |
2947 | -- than the size of System.Address. The exception is on VMS, where | |
2948 | -- we have short and long addresses, and it is possible for an access | |
2949 | -- type to have a short address size (and thus be less than the size | |
2950 | -- of System.Address itself). We simply skip the check for VMS, and | |
2951 | -- leave the back end to do the check. | |
d6f39728 | 2952 | |
2953 | elsif Is_Access_Type (T) then | |
93735cb8 | 2954 | if OpenVMS_On_Target then |
2955 | return 0; | |
2956 | else | |
2957 | return System_Address_Size; | |
2958 | end if; | |
d6f39728 | 2959 | |
2960 | -- Floating-point types | |
2961 | ||
2962 | elsif Is_Floating_Point_Type (T) then | |
f15731c4 | 2963 | return UI_To_Int (Esize (R_Typ)); |
d6f39728 | 2964 | |
2965 | -- Discrete types | |
2966 | ||
2967 | elsif Is_Discrete_Type (T) then | |
2968 | ||
2969 | -- The following loop is looking for the nearest compile time | |
2970 | -- known bounds following the ancestor subtype chain. The idea | |
2971 | -- is to find the most restrictive known bounds information. | |
2972 | ||
2973 | Ancest := T; | |
2974 | loop | |
2975 | if Ancest = Any_Type or else Etype (Ancest) = Any_Type then | |
2976 | return 0; | |
2977 | end if; | |
2978 | ||
2979 | if not LoSet then | |
2980 | if Compile_Time_Known_Value (Type_Low_Bound (Ancest)) then | |
2981 | Lo := Expr_Rep_Value (Type_Low_Bound (Ancest)); | |
2982 | LoSet := True; | |
2983 | exit when HiSet; | |
2984 | end if; | |
2985 | end if; | |
2986 | ||
2987 | if not HiSet then | |
2988 | if Compile_Time_Known_Value (Type_High_Bound (Ancest)) then | |
2989 | Hi := Expr_Rep_Value (Type_High_Bound (Ancest)); | |
2990 | HiSet := True; | |
2991 | exit when LoSet; | |
2992 | end if; | |
2993 | end if; | |
2994 | ||
2995 | Ancest := Ancestor_Subtype (Ancest); | |
2996 | ||
2997 | if No (Ancest) then | |
2998 | Ancest := Base_Type (T); | |
2999 | ||
3000 | if Is_Generic_Type (Ancest) then | |
3001 | return 0; | |
3002 | end if; | |
3003 | end if; | |
3004 | end loop; | |
3005 | ||
3006 | -- Fixed-point types. We can't simply use Expr_Value to get the | |
3007 | -- Corresponding_Integer_Value values of the bounds, since these | |
3008 | -- do not get set till the type is frozen, and this routine can | |
3009 | -- be called before the type is frozen. Similarly the test for | |
3010 | -- bounds being static needs to include the case where we have | |
3011 | -- unanalyzed real literals for the same reason. | |
3012 | ||
3013 | elsif Is_Fixed_Point_Type (T) then | |
3014 | ||
3015 | -- The following loop is looking for the nearest compile time | |
3016 | -- known bounds following the ancestor subtype chain. The idea | |
3017 | -- is to find the most restrictive known bounds information. | |
3018 | ||
3019 | Ancest := T; | |
3020 | loop | |
3021 | if Ancest = Any_Type or else Etype (Ancest) = Any_Type then | |
3022 | return 0; | |
3023 | end if; | |
3024 | ||
3025 | if not LoSet then | |
3026 | if Nkind (Type_Low_Bound (Ancest)) = N_Real_Literal | |
3027 | or else Compile_Time_Known_Value (Type_Low_Bound (Ancest)) | |
3028 | then | |
3029 | LoR := Expr_Value_R (Type_Low_Bound (Ancest)); | |
3030 | LoSet := True; | |
3031 | exit when HiSet; | |
3032 | end if; | |
3033 | end if; | |
3034 | ||
3035 | if not HiSet then | |
3036 | if Nkind (Type_High_Bound (Ancest)) = N_Real_Literal | |
3037 | or else Compile_Time_Known_Value (Type_High_Bound (Ancest)) | |
3038 | then | |
3039 | HiR := Expr_Value_R (Type_High_Bound (Ancest)); | |
3040 | HiSet := True; | |
3041 | exit when LoSet; | |
3042 | end if; | |
3043 | end if; | |
3044 | ||
3045 | Ancest := Ancestor_Subtype (Ancest); | |
3046 | ||
3047 | if No (Ancest) then | |
3048 | Ancest := Base_Type (T); | |
3049 | ||
3050 | if Is_Generic_Type (Ancest) then | |
3051 | return 0; | |
3052 | end if; | |
3053 | end if; | |
3054 | end loop; | |
3055 | ||
3056 | Lo := UR_To_Uint (LoR / Small_Value (T)); | |
3057 | Hi := UR_To_Uint (HiR / Small_Value (T)); | |
3058 | ||
3059 | -- No other types allowed | |
3060 | ||
3061 | else | |
3062 | raise Program_Error; | |
3063 | end if; | |
3064 | ||
2866d595 | 3065 | -- Fall through with Hi and Lo set. Deal with biased case |
d6f39728 | 3066 | |
3067 | if (Biased and then not Is_Fixed_Point_Type (T)) | |
3068 | or else Has_Biased_Representation (T) | |
3069 | then | |
3070 | Hi := Hi - Lo; | |
3071 | Lo := Uint_0; | |
3072 | end if; | |
3073 | ||
3074 | -- Signed case. Note that we consider types like range 1 .. -1 to be | |
3075 | -- signed for the purpose of computing the size, since the bounds | |
3076 | -- have to be accomodated in the base type. | |
3077 | ||
3078 | if Lo < 0 or else Hi < 0 then | |
3079 | S := 1; | |
3080 | B := Uint_1; | |
3081 | ||
da253936 | 3082 | -- S = size, B = 2 ** (size - 1) (can accommodate -B .. +(B - 1)) |
3083 | -- Note that we accommodate the case where the bounds cross. This | |
d6f39728 | 3084 | -- can happen either because of the way the bounds are declared |
3085 | -- or because of the algorithm in Freeze_Fixed_Point_Type. | |
3086 | ||
3087 | while Lo < -B | |
3088 | or else Hi < -B | |
3089 | or else Lo >= B | |
3090 | or else Hi >= B | |
3091 | loop | |
3092 | B := Uint_2 ** S; | |
3093 | S := S + 1; | |
3094 | end loop; | |
3095 | ||
3096 | -- Unsigned case | |
3097 | ||
3098 | else | |
3099 | -- If both bounds are positive, make sure that both are represen- | |
3100 | -- table in the case where the bounds are crossed. This can happen | |
3101 | -- either because of the way the bounds are declared, or because of | |
3102 | -- the algorithm in Freeze_Fixed_Point_Type. | |
3103 | ||
3104 | if Lo > Hi then | |
3105 | Hi := Lo; | |
3106 | end if; | |
3107 | ||
da253936 | 3108 | -- S = size, (can accommodate 0 .. (2**size - 1)) |
d6f39728 | 3109 | |
3110 | S := 0; | |
3111 | while Hi >= Uint_2 ** S loop | |
3112 | S := S + 1; | |
3113 | end loop; | |
3114 | end if; | |
3115 | ||
3116 | return S; | |
3117 | end Minimum_Size; | |
3118 | ||
3119 | ------------------------- | |
3120 | -- New_Stream_Function -- | |
3121 | ------------------------- | |
3122 | ||
3123 | procedure New_Stream_Function | |
3124 | (N : Node_Id; | |
3125 | Ent : Entity_Id; | |
3126 | Subp : Entity_Id; | |
9dfe12ae | 3127 | Nam : TSS_Name_Type) |
d6f39728 | 3128 | is |
3129 | Loc : constant Source_Ptr := Sloc (N); | |
9dfe12ae | 3130 | Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam); |
f15731c4 | 3131 | Subp_Id : Entity_Id; |
d6f39728 | 3132 | Subp_Decl : Node_Id; |
3133 | F : Entity_Id; | |
3134 | Etyp : Entity_Id; | |
3135 | ||
f15731c4 | 3136 | function Build_Spec return Node_Id; |
3137 | -- Used for declaration and renaming declaration, so that this is | |
3138 | -- treated as a renaming_as_body. | |
3139 | ||
3140 | ---------------- | |
3141 | -- Build_Spec -- | |
3142 | ---------------- | |
3143 | ||
d5b349fa | 3144 | function Build_Spec return Node_Id is |
f15731c4 | 3145 | begin |
9dfe12ae | 3146 | Subp_Id := Make_Defining_Identifier (Loc, Sname); |
f15731c4 | 3147 | |
3148 | return | |
3149 | Make_Function_Specification (Loc, | |
3150 | Defining_Unit_Name => Subp_Id, | |
3151 | Parameter_Specifications => | |
3152 | New_List ( | |
3153 | Make_Parameter_Specification (Loc, | |
3154 | Defining_Identifier => | |
3155 | Make_Defining_Identifier (Loc, Name_S), | |
3156 | Parameter_Type => | |
3157 | Make_Access_Definition (Loc, | |
3158 | Subtype_Mark => | |
3159 | New_Reference_To ( | |
3160 | Designated_Type (Etype (F)), Loc)))), | |
3161 | ||
d9125581 | 3162 | Result_Definition => |
f15731c4 | 3163 | New_Reference_To (Etyp, Loc)); |
3164 | end Build_Spec; | |
3165 | ||
3166 | -- Start of processing for New_Stream_Function | |
3167 | ||
d6f39728 | 3168 | begin |
f15731c4 | 3169 | F := First_Formal (Subp); |
3170 | Etyp := Etype (Subp); | |
3171 | ||
3172 | if not Is_Tagged_Type (Ent) then | |
3173 | Subp_Decl := | |
3174 | Make_Subprogram_Declaration (Loc, | |
3175 | Specification => Build_Spec); | |
3176 | Insert_Action (N, Subp_Decl); | |
3177 | end if; | |
d6f39728 | 3178 | |
3179 | Subp_Decl := | |
3180 | Make_Subprogram_Renaming_Declaration (Loc, | |
f15731c4 | 3181 | Specification => Build_Spec, |
3182 | Name => New_Reference_To (Subp, Loc)); | |
d6f39728 | 3183 | |
74f1481b | 3184 | if Is_Tagged_Type (Ent) then |
d6f39728 | 3185 | Set_TSS (Base_Type (Ent), Subp_Id); |
3186 | else | |
3187 | Insert_Action (N, Subp_Decl); | |
3188 | Copy_TSS (Subp_Id, Base_Type (Ent)); | |
3189 | end if; | |
d6f39728 | 3190 | end New_Stream_Function; |
3191 | ||
3192 | -------------------------- | |
3193 | -- New_Stream_Procedure -- | |
3194 | -------------------------- | |
3195 | ||
3196 | procedure New_Stream_Procedure | |
3197 | (N : Node_Id; | |
3198 | Ent : Entity_Id; | |
3199 | Subp : Entity_Id; | |
9dfe12ae | 3200 | Nam : TSS_Name_Type; |
d6f39728 | 3201 | Out_P : Boolean := False) |
3202 | is | |
3203 | Loc : constant Source_Ptr := Sloc (N); | |
9dfe12ae | 3204 | Sname : constant Name_Id := Make_TSS_Name (Base_Type (Ent), Nam); |
f15731c4 | 3205 | Subp_Id : Entity_Id; |
d6f39728 | 3206 | Subp_Decl : Node_Id; |
3207 | F : Entity_Id; | |
3208 | Etyp : Entity_Id; | |
3209 | ||
f15731c4 | 3210 | function Build_Spec return Node_Id; |
3211 | -- Used for declaration and renaming declaration, so that this is | |
3212 | -- treated as a renaming_as_body. | |
3213 | ||
9dfe12ae | 3214 | ---------------- |
3215 | -- Build_Spec -- | |
3216 | ---------------- | |
3217 | ||
d5b349fa | 3218 | function Build_Spec return Node_Id is |
f15731c4 | 3219 | begin |
9dfe12ae | 3220 | Subp_Id := Make_Defining_Identifier (Loc, Sname); |
f15731c4 | 3221 | |
3222 | return | |
3223 | Make_Procedure_Specification (Loc, | |
3224 | Defining_Unit_Name => Subp_Id, | |
3225 | Parameter_Specifications => | |
3226 | New_List ( | |
3227 | Make_Parameter_Specification (Loc, | |
3228 | Defining_Identifier => | |
3229 | Make_Defining_Identifier (Loc, Name_S), | |
3230 | Parameter_Type => | |
3231 | Make_Access_Definition (Loc, | |
3232 | Subtype_Mark => | |
3233 | New_Reference_To ( | |
3234 | Designated_Type (Etype (F)), Loc))), | |
3235 | ||
3236 | Make_Parameter_Specification (Loc, | |
3237 | Defining_Identifier => | |
3238 | Make_Defining_Identifier (Loc, Name_V), | |
3239 | Out_Present => Out_P, | |
3240 | Parameter_Type => | |
3241 | New_Reference_To (Etyp, Loc)))); | |
3242 | end Build_Spec; | |
3243 | ||
9dfe12ae | 3244 | -- Start of processing for New_Stream_Procedure |
f15731c4 | 3245 | |
d6f39728 | 3246 | begin |
3247 | F := First_Formal (Subp); | |
3248 | Etyp := Etype (Next_Formal (F)); | |
3249 | ||
f15731c4 | 3250 | if not Is_Tagged_Type (Ent) then |
3251 | Subp_Decl := | |
3252 | Make_Subprogram_Declaration (Loc, | |
3253 | Specification => Build_Spec); | |
3254 | Insert_Action (N, Subp_Decl); | |
3255 | end if; | |
3256 | ||
d6f39728 | 3257 | Subp_Decl := |
3258 | Make_Subprogram_Renaming_Declaration (Loc, | |
f15731c4 | 3259 | Specification => Build_Spec, |
3260 | Name => New_Reference_To (Subp, Loc)); | |
d6f39728 | 3261 | |
74f1481b | 3262 | if Is_Tagged_Type (Ent) then |
d6f39728 | 3263 | Set_TSS (Base_Type (Ent), Subp_Id); |
3264 | else | |
3265 | Insert_Action (N, Subp_Decl); | |
3266 | Copy_TSS (Subp_Id, Base_Type (Ent)); | |
3267 | end if; | |
d6f39728 | 3268 | end New_Stream_Procedure; |
3269 | ||
d6f39728 | 3270 | ------------------------ |
3271 | -- Rep_Item_Too_Early -- | |
3272 | ------------------------ | |
3273 | ||
80d4fec4 | 3274 | function Rep_Item_Too_Early (T : Entity_Id; N : Node_Id) return Boolean is |
d6f39728 | 3275 | begin |
f15731c4 | 3276 | -- Cannot apply rep items that are not operational items |
3277 | -- to generic types | |
d6f39728 | 3278 | |
f15731c4 | 3279 | if Is_Operational_Item (N) then |
3280 | return False; | |
3281 | ||
3282 | elsif Is_Type (T) | |
d6f39728 | 3283 | and then Is_Generic_Type (Root_Type (T)) |
3284 | then | |
3285 | Error_Msg_N | |
3286 | ("representation item not allowed for generic type", N); | |
3287 | return True; | |
3288 | end if; | |
3289 | ||
3290 | -- Otherwise check for incompleted type | |
3291 | ||
3292 | if Is_Incomplete_Or_Private_Type (T) | |
3293 | and then No (Underlying_Type (T)) | |
3294 | then | |
3295 | Error_Msg_N | |
3296 | ("representation item must be after full type declaration", N); | |
3297 | return True; | |
3298 | ||
3299 | -- If the type has incompleted components, a representation clause is | |
3300 | -- illegal but stream attributes and Convention pragmas are correct. | |
3301 | ||
3302 | elsif Has_Private_Component (T) then | |
f15731c4 | 3303 | if Nkind (N) = N_Pragma then |
d6f39728 | 3304 | return False; |
3305 | else | |
3306 | Error_Msg_N | |
3307 | ("representation item must appear after type is fully defined", | |
3308 | N); | |
3309 | return True; | |
3310 | end if; | |
3311 | else | |
3312 | return False; | |
3313 | end if; | |
3314 | end Rep_Item_Too_Early; | |
3315 | ||
3316 | ----------------------- | |
3317 | -- Rep_Item_Too_Late -- | |
3318 | ----------------------- | |
3319 | ||
3320 | function Rep_Item_Too_Late | |
3321 | (T : Entity_Id; | |
3322 | N : Node_Id; | |
d5b349fa | 3323 | FOnly : Boolean := False) return Boolean |
d6f39728 | 3324 | is |
3325 | S : Entity_Id; | |
3326 | Parent_Type : Entity_Id; | |
3327 | ||
3328 | procedure Too_Late; | |
d53a018a | 3329 | -- Output the too late message. Note that this is not considered a |
3330 | -- serious error, since the effect is simply that we ignore the | |
3331 | -- representation clause in this case. | |
3332 | ||
3333 | -------------- | |
3334 | -- Too_Late -- | |
3335 | -------------- | |
d6f39728 | 3336 | |
3337 | procedure Too_Late is | |
3338 | begin | |
d53a018a | 3339 | Error_Msg_N ("|representation item appears too late!", N); |
d6f39728 | 3340 | end Too_Late; |
3341 | ||
3342 | -- Start of processing for Rep_Item_Too_Late | |
3343 | ||
3344 | begin | |
3345 | -- First make sure entity is not frozen (RM 13.1(9)). Exclude imported | |
3346 | -- types, which may be frozen if they appear in a representation clause | |
3347 | -- for a local type. | |
3348 | ||
3349 | if Is_Frozen (T) | |
3350 | and then not From_With_Type (T) | |
3351 | then | |
3352 | Too_Late; | |
3353 | S := First_Subtype (T); | |
3354 | ||
3355 | if Present (Freeze_Node (S)) then | |
3356 | Error_Msg_NE | |
87d5c1d0 | 3357 | ("?no more representation items for }", Freeze_Node (S), S); |
d6f39728 | 3358 | end if; |
3359 | ||
3360 | return True; | |
3361 | ||
3362 | -- Check for case of non-tagged derived type whose parent either has | |
3363 | -- primitive operations, or is a by reference type (RM 13.1(10)). | |
3364 | ||
3365 | elsif Is_Type (T) | |
3366 | and then not FOnly | |
3367 | and then Is_Derived_Type (T) | |
3368 | and then not Is_Tagged_Type (T) | |
3369 | then | |
3370 | Parent_Type := Etype (Base_Type (T)); | |
3371 | ||
3372 | if Has_Primitive_Operations (Parent_Type) then | |
3373 | Too_Late; | |
3374 | Error_Msg_NE | |
3375 | ("primitive operations already defined for&!", N, Parent_Type); | |
3376 | return True; | |
3377 | ||
3378 | elsif Is_By_Reference_Type (Parent_Type) then | |
3379 | Too_Late; | |
3380 | Error_Msg_NE | |
3381 | ("parent type & is a by reference type!", N, Parent_Type); | |
3382 | return True; | |
3383 | end if; | |
3384 | end if; | |
3385 | ||
3386 | -- No error, link item into head of chain of rep items for the entity | |
3387 | ||
3388 | Record_Rep_Item (T, N); | |
3389 | return False; | |
3390 | end Rep_Item_Too_Late; | |
3391 | ||
3392 | ------------------------- | |
3393 | -- Same_Representation -- | |
3394 | ------------------------- | |
3395 | ||
3396 | function Same_Representation (Typ1, Typ2 : Entity_Id) return Boolean is | |
3397 | T1 : constant Entity_Id := Underlying_Type (Typ1); | |
3398 | T2 : constant Entity_Id := Underlying_Type (Typ2); | |
3399 | ||
3400 | begin | |
3401 | -- A quick check, if base types are the same, then we definitely have | |
3402 | -- the same representation, because the subtype specific representation | |
3403 | -- attributes (Size and Alignment) do not affect representation from | |
3404 | -- the point of view of this test. | |
3405 | ||
3406 | if Base_Type (T1) = Base_Type (T2) then | |
3407 | return True; | |
3408 | ||
3409 | elsif Is_Private_Type (Base_Type (T2)) | |
3410 | and then Base_Type (T1) = Full_View (Base_Type (T2)) | |
3411 | then | |
3412 | return True; | |
3413 | end if; | |
3414 | ||
3415 | -- Tagged types never have differing representations | |
3416 | ||
3417 | if Is_Tagged_Type (T1) then | |
3418 | return True; | |
3419 | end if; | |
3420 | ||
3421 | -- Representations are definitely different if conventions differ | |
3422 | ||
3423 | if Convention (T1) /= Convention (T2) then | |
3424 | return False; | |
3425 | end if; | |
3426 | ||
3427 | -- Representations are different if component alignments differ | |
3428 | ||
3429 | if (Is_Record_Type (T1) or else Is_Array_Type (T1)) | |
3430 | and then | |
3431 | (Is_Record_Type (T2) or else Is_Array_Type (T2)) | |
3432 | and then Component_Alignment (T1) /= Component_Alignment (T2) | |
3433 | then | |
3434 | return False; | |
3435 | end if; | |
3436 | ||
3437 | -- For arrays, the only real issue is component size. If we know the | |
3438 | -- component size for both arrays, and it is the same, then that's | |
3439 | -- good enough to know we don't have a change of representation. | |
3440 | ||
3441 | if Is_Array_Type (T1) then | |
3442 | if Known_Component_Size (T1) | |
3443 | and then Known_Component_Size (T2) | |
3444 | and then Component_Size (T1) = Component_Size (T2) | |
3445 | then | |
3446 | return True; | |
3447 | end if; | |
3448 | end if; | |
3449 | ||
3450 | -- Types definitely have same representation if neither has non-standard | |
3451 | -- representation since default representations are always consistent. | |
3452 | -- If only one has non-standard representation, and the other does not, | |
3453 | -- then we consider that they do not have the same representation. They | |
3454 | -- might, but there is no way of telling early enough. | |
3455 | ||
3456 | if Has_Non_Standard_Rep (T1) then | |
3457 | if not Has_Non_Standard_Rep (T2) then | |
3458 | return False; | |
3459 | end if; | |
3460 | else | |
3461 | return not Has_Non_Standard_Rep (T2); | |
3462 | end if; | |
3463 | ||
3464 | -- Here the two types both have non-standard representation, and we | |
3465 | -- need to determine if they have the same non-standard representation | |
3466 | ||
3467 | -- For arrays, we simply need to test if the component sizes are the | |
3468 | -- same. Pragma Pack is reflected in modified component sizes, so this | |
3469 | -- check also deals with pragma Pack. | |
3470 | ||
3471 | if Is_Array_Type (T1) then | |
3472 | return Component_Size (T1) = Component_Size (T2); | |
3473 | ||
3474 | -- Tagged types always have the same representation, because it is not | |
3475 | -- possible to specify different representations for common fields. | |
3476 | ||
3477 | elsif Is_Tagged_Type (T1) then | |
3478 | return True; | |
3479 | ||
3480 | -- Case of record types | |
3481 | ||
3482 | elsif Is_Record_Type (T1) then | |
3483 | ||
3484 | -- Packed status must conform | |
3485 | ||
3486 | if Is_Packed (T1) /= Is_Packed (T2) then | |
3487 | return False; | |
3488 | ||
3489 | -- Otherwise we must check components. Typ2 maybe a constrained | |
3490 | -- subtype with fewer components, so we compare the components | |
3491 | -- of the base types. | |
3492 | ||
3493 | else | |
3494 | Record_Case : declare | |
3495 | CD1, CD2 : Entity_Id; | |
3496 | ||
3497 | function Same_Rep return Boolean; | |
3498 | -- CD1 and CD2 are either components or discriminants. This | |
3499 | -- function tests whether the two have the same representation | |
3500 | ||
80d4fec4 | 3501 | -------------- |
3502 | -- Same_Rep -- | |
3503 | -------------- | |
3504 | ||
d6f39728 | 3505 | function Same_Rep return Boolean is |
3506 | begin | |
3507 | if No (Component_Clause (CD1)) then | |
3508 | return No (Component_Clause (CD2)); | |
3509 | ||
3510 | else | |
3511 | return | |
3512 | Present (Component_Clause (CD2)) | |
3513 | and then | |
3514 | Component_Bit_Offset (CD1) = Component_Bit_Offset (CD2) | |
3515 | and then | |
3516 | Esize (CD1) = Esize (CD2); | |
3517 | end if; | |
3518 | end Same_Rep; | |
3519 | ||
3520 | -- Start processing for Record_Case | |
3521 | ||
3522 | begin | |
3523 | if Has_Discriminants (T1) then | |
3524 | CD1 := First_Discriminant (T1); | |
3525 | CD2 := First_Discriminant (T2); | |
3526 | ||
9dfe12ae | 3527 | -- The number of discriminants may be different if the |
3528 | -- derived type has fewer (constrained by values). The | |
3529 | -- invisible discriminants retain the representation of | |
3530 | -- the original, so the discrepancy does not per se | |
3531 | -- indicate a different representation. | |
3532 | ||
3533 | while Present (CD1) | |
3534 | and then Present (CD2) | |
3535 | loop | |
d6f39728 | 3536 | if not Same_Rep then |
3537 | return False; | |
3538 | else | |
3539 | Next_Discriminant (CD1); | |
3540 | Next_Discriminant (CD2); | |
3541 | end if; | |
3542 | end loop; | |
3543 | end if; | |
3544 | ||
3545 | CD1 := First_Component (Underlying_Type (Base_Type (T1))); | |
3546 | CD2 := First_Component (Underlying_Type (Base_Type (T2))); | |
3547 | ||
3548 | while Present (CD1) loop | |
3549 | if not Same_Rep then | |
3550 | return False; | |
3551 | else | |
3552 | Next_Component (CD1); | |
3553 | Next_Component (CD2); | |
3554 | end if; | |
3555 | end loop; | |
3556 | ||
3557 | return True; | |
3558 | end Record_Case; | |
3559 | end if; | |
3560 | ||
3561 | -- For enumeration types, we must check each literal to see if the | |
3562 | -- representation is the same. Note that we do not permit enumeration | |
9dfe12ae | 3563 | -- reprsentation clauses for Character and Wide_Character, so these |
d6f39728 | 3564 | -- cases were already dealt with. |
3565 | ||
3566 | elsif Is_Enumeration_Type (T1) then | |
3567 | ||
3568 | Enumeration_Case : declare | |
3569 | L1, L2 : Entity_Id; | |
3570 | ||
3571 | begin | |
3572 | L1 := First_Literal (T1); | |
3573 | L2 := First_Literal (T2); | |
3574 | ||
3575 | while Present (L1) loop | |
3576 | if Enumeration_Rep (L1) /= Enumeration_Rep (L2) then | |
3577 | return False; | |
3578 | else | |
3579 | Next_Literal (L1); | |
3580 | Next_Literal (L2); | |
3581 | end if; | |
3582 | end loop; | |
3583 | ||
3584 | return True; | |
3585 | ||
3586 | end Enumeration_Case; | |
3587 | ||
3588 | -- Any other types have the same representation for these purposes | |
3589 | ||
3590 | else | |
3591 | return True; | |
3592 | end if; | |
d6f39728 | 3593 | end Same_Representation; |
3594 | ||
3595 | -------------------- | |
3596 | -- Set_Enum_Esize -- | |
3597 | -------------------- | |
3598 | ||
3599 | procedure Set_Enum_Esize (T : Entity_Id) is | |
3600 | Lo : Uint; | |
3601 | Hi : Uint; | |
3602 | Sz : Nat; | |
3603 | ||
3604 | begin | |
3605 | Init_Alignment (T); | |
3606 | ||
3607 | -- Find the minimum standard size (8,16,32,64) that fits | |
3608 | ||
3609 | Lo := Enumeration_Rep (Entity (Type_Low_Bound (T))); | |
3610 | Hi := Enumeration_Rep (Entity (Type_High_Bound (T))); | |
3611 | ||
3612 | if Lo < 0 then | |
3613 | if Lo >= -Uint_2**07 and then Hi < Uint_2**07 then | |
f15731c4 | 3614 | Sz := Standard_Character_Size; -- May be > 8 on some targets |
d6f39728 | 3615 | |
3616 | elsif Lo >= -Uint_2**15 and then Hi < Uint_2**15 then | |
3617 | Sz := 16; | |
3618 | ||
3619 | elsif Lo >= -Uint_2**31 and then Hi < Uint_2**31 then | |
3620 | Sz := 32; | |
3621 | ||
3622 | else pragma Assert (Lo >= -Uint_2**63 and then Hi < Uint_2**63); | |
3623 | Sz := 64; | |
3624 | end if; | |
3625 | ||
3626 | else | |
3627 | if Hi < Uint_2**08 then | |
f15731c4 | 3628 | Sz := Standard_Character_Size; -- May be > 8 on some targets |
d6f39728 | 3629 | |
3630 | elsif Hi < Uint_2**16 then | |
3631 | Sz := 16; | |
3632 | ||
3633 | elsif Hi < Uint_2**32 then | |
3634 | Sz := 32; | |
3635 | ||
3636 | else pragma Assert (Hi < Uint_2**63); | |
3637 | Sz := 64; | |
3638 | end if; | |
3639 | end if; | |
3640 | ||
3641 | -- That minimum is the proper size unless we have a foreign convention | |
3642 | -- and the size required is 32 or less, in which case we bump the size | |
3643 | -- up to 32. This is required for C and C++ and seems reasonable for | |
3644 | -- all other foreign conventions. | |
3645 | ||
3646 | if Has_Foreign_Convention (T) | |
3647 | and then Esize (T) < Standard_Integer_Size | |
3648 | then | |
3649 | Init_Esize (T, Standard_Integer_Size); | |
3650 | ||
3651 | else | |
3652 | Init_Esize (T, Sz); | |
3653 | end if; | |
d6f39728 | 3654 | end Set_Enum_Esize; |
3655 | ||
3656 | ----------------------------------- | |
3657 | -- Validate_Unchecked_Conversion -- | |
3658 | ----------------------------------- | |
3659 | ||
3660 | procedure Validate_Unchecked_Conversion | |
3661 | (N : Node_Id; | |
3662 | Act_Unit : Entity_Id) | |
3663 | is | |
3664 | Source : Entity_Id; | |
3665 | Target : Entity_Id; | |
3666 | Vnode : Node_Id; | |
3667 | ||
3668 | begin | |
3669 | -- Obtain source and target types. Note that we call Ancestor_Subtype | |
3670 | -- here because the processing for generic instantiation always makes | |
3671 | -- subtypes, and we want the original frozen actual types. | |
3672 | ||
3673 | -- If we are dealing with private types, then do the check on their | |
3674 | -- fully declared counterparts if the full declarations have been | |
3675 | -- encountered (they don't have to be visible, but they must exist!) | |
3676 | ||
3677 | Source := Ancestor_Subtype (Etype (First_Formal (Act_Unit))); | |
3678 | ||
3679 | if Is_Private_Type (Source) | |
3680 | and then Present (Underlying_Type (Source)) | |
3681 | then | |
3682 | Source := Underlying_Type (Source); | |
3683 | end if; | |
3684 | ||
3685 | Target := Ancestor_Subtype (Etype (Act_Unit)); | |
3686 | ||
3687 | -- If either type is generic, the instantiation happens within a | |
3688 | -- generic unit, and there is nothing to check. The proper check | |
3689 | -- will happen when the enclosing generic is instantiated. | |
3690 | ||
3691 | if Is_Generic_Type (Source) or else Is_Generic_Type (Target) then | |
3692 | return; | |
3693 | end if; | |
3694 | ||
3695 | if Is_Private_Type (Target) | |
3696 | and then Present (Underlying_Type (Target)) | |
3697 | then | |
3698 | Target := Underlying_Type (Target); | |
3699 | end if; | |
3700 | ||
3701 | -- Source may be unconstrained array, but not target | |
3702 | ||
3703 | if Is_Array_Type (Target) | |
3704 | and then not Is_Constrained (Target) | |
3705 | then | |
3706 | Error_Msg_N | |
3707 | ("unchecked conversion to unconstrained array not allowed", N); | |
3708 | return; | |
3709 | end if; | |
3710 | ||
3711 | -- Make entry in unchecked conversion table for later processing | |
3712 | -- by Validate_Unchecked_Conversions, which will check sizes and | |
3713 | -- alignments (using values set by the back-end where possible). | |
9dfe12ae | 3714 | -- This is only done if the appropriate warning is active |
d6f39728 | 3715 | |
9dfe12ae | 3716 | if Warn_On_Unchecked_Conversion then |
3717 | Unchecked_Conversions.Append | |
3718 | (New_Val => UC_Entry' | |
3719 | (Enode => N, | |
3720 | Source => Source, | |
3721 | Target => Target)); | |
3722 | ||
3723 | -- If both sizes are known statically now, then back end annotation | |
3724 | -- is not required to do a proper check but if either size is not | |
3725 | -- known statically, then we need the annotation. | |
3726 | ||
3727 | if Known_Static_RM_Size (Source) | |
3728 | and then Known_Static_RM_Size (Target) | |
3729 | then | |
3730 | null; | |
3731 | else | |
3732 | Back_Annotate_Rep_Info := True; | |
3733 | end if; | |
3734 | end if; | |
d6f39728 | 3735 | |
28ed91d4 | 3736 | -- If unchecked conversion to access type, and access type is |
3737 | -- declared in the same unit as the unchecked conversion, then | |
3738 | -- set the No_Strict_Aliasing flag (no strict aliasing is | |
3739 | -- implicit in this situation). | |
3740 | ||
3741 | if Is_Access_Type (Target) and then | |
3742 | In_Same_Source_Unit (Target, N) | |
3743 | then | |
3744 | Set_No_Strict_Aliasing (Implementation_Base_Type (Target)); | |
3745 | end if; | |
3d875462 | 3746 | |
3747 | -- Generate N_Validate_Unchecked_Conversion node for back end in | |
3748 | -- case the back end needs to perform special validation checks. | |
3749 | ||
3750 | -- Shouldn't this be in exp_ch13, since the check only gets done | |
3751 | -- if we have full expansion and the back end is called ??? | |
3752 | ||
3753 | Vnode := | |
3754 | Make_Validate_Unchecked_Conversion (Sloc (N)); | |
3755 | Set_Source_Type (Vnode, Source); | |
3756 | Set_Target_Type (Vnode, Target); | |
3757 | ||
3758 | -- If the unchecked conversion node is in a list, just insert before | |
3759 | -- it. If not we have some strange case, not worth bothering about. | |
3760 | ||
3761 | if Is_List_Member (N) then | |
d6f39728 | 3762 | Insert_After (N, Vnode); |
3763 | end if; | |
3764 | end Validate_Unchecked_Conversion; | |
3765 | ||
3766 | ------------------------------------ | |
3767 | -- Validate_Unchecked_Conversions -- | |
3768 | ------------------------------------ | |
3769 | ||
3770 | procedure Validate_Unchecked_Conversions is | |
3771 | begin | |
3772 | for N in Unchecked_Conversions.First .. Unchecked_Conversions.Last loop | |
3773 | declare | |
3774 | T : UC_Entry renames Unchecked_Conversions.Table (N); | |
3775 | ||
3776 | Enode : constant Node_Id := T.Enode; | |
3777 | Source : constant Entity_Id := T.Source; | |
3778 | Target : constant Entity_Id := T.Target; | |
3779 | ||
3780 | Source_Siz : Uint; | |
3781 | Target_Siz : Uint; | |
3782 | ||
3783 | begin | |
3784 | -- This validation check, which warns if we have unequal sizes | |
3785 | -- for unchecked conversion, and thus potentially implementation | |
3786 | -- dependent semantics, is one of the few occasions on which we | |
3787 | -- use the official RM size instead of Esize. See description | |
3788 | -- in Einfo "Handling of Type'Size Values" for details. | |
3789 | ||
f15731c4 | 3790 | if Serious_Errors_Detected = 0 |
d6f39728 | 3791 | and then Known_Static_RM_Size (Source) |
3792 | and then Known_Static_RM_Size (Target) | |
3793 | then | |
3794 | Source_Siz := RM_Size (Source); | |
3795 | Target_Siz := RM_Size (Target); | |
3796 | ||
3797 | if Source_Siz /= Target_Siz then | |
d6f39728 | 3798 | Error_Msg_N |
3799 | ("types for unchecked conversion have different sizes?", | |
3800 | Enode); | |
3801 | ||
3802 | if All_Errors_Mode then | |
3803 | Error_Msg_Name_1 := Chars (Source); | |
3804 | Error_Msg_Uint_1 := Source_Siz; | |
3805 | Error_Msg_Name_2 := Chars (Target); | |
3806 | Error_Msg_Uint_2 := Target_Siz; | |
3807 | Error_Msg_N | |
3808 | ("\size of % is ^, size of % is ^?", Enode); | |
3809 | ||
3810 | Error_Msg_Uint_1 := UI_Abs (Source_Siz - Target_Siz); | |
3811 | ||
3812 | if Is_Discrete_Type (Source) | |
3813 | and then Is_Discrete_Type (Target) | |
3814 | then | |
3815 | if Source_Siz > Target_Siz then | |
3816 | Error_Msg_N | |
3817 | ("\^ high order bits of source will be ignored?", | |
3818 | Enode); | |
3819 | ||
9dfe12ae | 3820 | elsif Is_Unsigned_Type (Source) then |
d6f39728 | 3821 | Error_Msg_N |
3822 | ("\source will be extended with ^ high order " & | |
3823 | "zero bits?", Enode); | |
3824 | ||
3825 | else | |
3826 | Error_Msg_N | |
3827 | ("\source will be extended with ^ high order " & | |
3828 | "sign bits?", | |
3829 | Enode); | |
3830 | end if; | |
3831 | ||
3832 | elsif Source_Siz < Target_Siz then | |
3833 | if Is_Discrete_Type (Target) then | |
3834 | if Bytes_Big_Endian then | |
3835 | Error_Msg_N | |
3836 | ("\target value will include ^ undefined " & | |
3837 | "low order bits?", | |
3838 | Enode); | |
3839 | else | |
3840 | Error_Msg_N | |
3841 | ("\target value will include ^ undefined " & | |
3842 | "high order bits?", | |
3843 | Enode); | |
3844 | end if; | |
3845 | ||
3846 | else | |
3847 | Error_Msg_N | |
3848 | ("\^ trailing bits of target value will be " & | |
3849 | "undefined?", Enode); | |
3850 | end if; | |
3851 | ||
3852 | else pragma Assert (Source_Siz > Target_Siz); | |
3853 | Error_Msg_N | |
3854 | ("\^ trailing bits of source will be ignored?", | |
3855 | Enode); | |
3856 | end if; | |
3857 | end if; | |
d6f39728 | 3858 | end if; |
3859 | end if; | |
3860 | ||
3861 | -- If both types are access types, we need to check the alignment. | |
3862 | -- If the alignment of both is specified, we can do it here. | |
3863 | ||
f15731c4 | 3864 | if Serious_Errors_Detected = 0 |
d6f39728 | 3865 | and then Ekind (Source) in Access_Kind |
3866 | and then Ekind (Target) in Access_Kind | |
3867 | and then Target_Strict_Alignment | |
3868 | and then Present (Designated_Type (Source)) | |
3869 | and then Present (Designated_Type (Target)) | |
3870 | then | |
3871 | declare | |
3872 | D_Source : constant Entity_Id := Designated_Type (Source); | |
3873 | D_Target : constant Entity_Id := Designated_Type (Target); | |
3874 | ||
3875 | begin | |
3876 | if Known_Alignment (D_Source) | |
3877 | and then Known_Alignment (D_Target) | |
3878 | then | |
3879 | declare | |
3880 | Source_Align : constant Uint := Alignment (D_Source); | |
3881 | Target_Align : constant Uint := Alignment (D_Target); | |
3882 | ||
3883 | begin | |
3884 | if Source_Align < Target_Align | |
3885 | and then not Is_Tagged_Type (D_Source) | |
3886 | then | |
d6f39728 | 3887 | Error_Msg_Uint_1 := Target_Align; |
3888 | Error_Msg_Uint_2 := Source_Align; | |
3889 | Error_Msg_Node_2 := D_Source; | |
3890 | Error_Msg_NE | |
3891 | ("alignment of & (^) is stricter than " & | |
3892 | "alignment of & (^)?", Enode, D_Target); | |
3893 | ||
3894 | if All_Errors_Mode then | |
3895 | Error_Msg_N | |
3896 | ("\resulting access value may have invalid " & | |
3897 | "alignment?", Enode); | |
3898 | end if; | |
d6f39728 | 3899 | end if; |
3900 | end; | |
3901 | end if; | |
3902 | end; | |
3903 | end if; | |
3904 | end; | |
3905 | end loop; | |
3906 | end Validate_Unchecked_Conversions; | |
3907 | ||
d6f39728 | 3908 | end Sem_Ch13; |