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2009-07-13 Emmanuel Briot <briot@adacore.com>
[thirdparty/gcc.git] / gcc / ada / exp_attr.adb
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ee6ba406 1------------------------------------------------------------------------------
2-- --
3-- GNAT COMPILER COMPONENTS --
4-- --
5-- E X P _ A T T R --
6-- --
7-- B o d y --
8-- --
6bc9506f 9-- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
ee6ba406 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- --
6bc9506f 13-- ware Foundation; either version 3, or (at your option) any later ver- --
ee6ba406 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 --
6bc9506f 16-- or FITNESS FOR A PARTICULAR PURPOSE. --
17-- --
18-- You should have received a copy of the GNU General Public License along --
19-- with this program; see file COPYING3. If not see --
20-- <http://www.gnu.org/licenses/>. --
ee6ba406 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. --
ee6ba406 24-- --
25------------------------------------------------------------------------------
26
27with Atree; use Atree;
28with Checks; use Checks;
29with Einfo; use Einfo;
00f91aef 30with Elists; use Elists;
99f2248e 31with Exp_Atag; use Exp_Atag;
ee6ba406 32with Exp_Ch2; use Exp_Ch2;
d55c93e0 33with Exp_Ch3; use Exp_Ch3;
34with Exp_Ch6; use Exp_Ch6;
ee6ba406 35with Exp_Ch9; use Exp_Ch9;
5690e662 36with Exp_Dist; use Exp_Dist;
ee6ba406 37with Exp_Imgv; use Exp_Imgv;
38with Exp_Pakd; use Exp_Pakd;
39with Exp_Strm; use Exp_Strm;
40with Exp_Tss; use Exp_Tss;
41with Exp_Util; use Exp_Util;
6e62b6c3 42with Exp_VFpt; use Exp_VFpt;
d55c93e0 43with Fname; use Fname;
db14252c 44with Freeze; use Freeze;
ee6ba406 45with Gnatvsn; use Gnatvsn;
db14252c 46with Itypes; use Itypes;
ee6ba406 47with Lib; use Lib;
48with Namet; use Namet;
49with Nmake; use Nmake;
50with Nlists; use Nlists;
51with Opt; use Opt;
52with Restrict; use Restrict;
1e16c51c 53with Rident; use Rident;
ee6ba406 54with Rtsfind; use Rtsfind;
55with Sem; use Sem;
d60c9ff7 56with Sem_Aux; use Sem_Aux;
4c06b9d2 57with Sem_Ch6; use Sem_Ch6;
ee6ba406 58with Sem_Ch7; use Sem_Ch7;
59with Sem_Ch8; use Sem_Ch8;
ee6ba406 60with Sem_Eval; use Sem_Eval;
61with Sem_Res; use Sem_Res;
62with Sem_Util; use Sem_Util;
63with Sinfo; use Sinfo;
64with Snames; use Snames;
65with Stand; use Stand;
66with Stringt; use Stringt;
83aa52b6 67with Targparm; use Targparm;
ee6ba406 68with Tbuild; use Tbuild;
69with Ttypes; use Ttypes;
70with Uintp; use Uintp;
71with Uname; use Uname;
72with Validsw; use Validsw;
73
74package body Exp_Attr is
75
76 -----------------------
77 -- Local Subprograms --
78 -----------------------
79
80 procedure Compile_Stream_Body_In_Scope
81 (N : Node_Id;
82 Decl : Node_Id;
83 Arr : Entity_Id;
84 Check : Boolean);
85 -- The body for a stream subprogram may be generated outside of the scope
86 -- of the type. If the type is fully private, it may depend on the full
87 -- view of other types (e.g. indices) that are currently private as well.
88 -- We install the declarations of the package in which the type is declared
89 -- before compiling the body in what is its proper environment. The Check
90 -- parameter indicates if checks are to be suppressed for the stream body.
91 -- We suppress checks for array/record reads, since the rule is that these
92 -- are like assignments, out of range values due to uninitialized storage,
93 -- or other invalid values do NOT cause a Constraint_Error to be raised.
94
7f8eb6ed 95 procedure Expand_Access_To_Protected_Op
96 (N : Node_Id;
97 Pref : Node_Id;
98 Typ : Entity_Id);
99
100 -- An attribute reference to a protected subprogram is transformed into
101 -- a pair of pointers: one to the object, and one to the operations.
102 -- This expansion is performed for 'Access and for 'Unrestricted_Access.
103
ee6ba406 104 procedure Expand_Fpt_Attribute
9dfe12ae 105 (N : Node_Id;
1550b445 106 Pkg : RE_Id;
9dfe12ae 107 Nam : Name_Id;
ee6ba406 108 Args : List_Id);
109 -- This procedure expands a call to a floating-point attribute function.
110 -- N is the attribute reference node, and Args is a list of arguments to
1550b445 111 -- be passed to the function call. Pkg identifies the package containing
112 -- the appropriate instantiation of System.Fat_Gen. Float arguments in Args
113 -- have already been converted to the floating-point type for which Pkg was
114 -- instantiated. The Nam argument is the relevant attribute processing
115 -- routine to be called. This is the same as the attribute name, except in
116 -- the Unaligned_Valid case.
ee6ba406 117
118 procedure Expand_Fpt_Attribute_R (N : Node_Id);
119 -- This procedure expands a call to a floating-point attribute function
9dfe12ae 120 -- that takes a single floating-point argument. The function to be called
121 -- is always the same as the attribute name.
ee6ba406 122
123 procedure Expand_Fpt_Attribute_RI (N : Node_Id);
124 -- This procedure expands a call to a floating-point attribute function
9dfe12ae 125 -- that takes one floating-point argument and one integer argument. The
126 -- function to be called is always the same as the attribute name.
ee6ba406 127
128 procedure Expand_Fpt_Attribute_RR (N : Node_Id);
129 -- This procedure expands a call to a floating-point attribute function
9dfe12ae 130 -- that takes two floating-point arguments. The function to be called
131 -- is always the same as the attribute name.
ee6ba406 132
133 procedure Expand_Pred_Succ (N : Node_Id);
134 -- Handles expansion of Pred or Succ attributes for case of non-real
135 -- operand with overflow checking required.
136
137 function Get_Index_Subtype (N : Node_Id) return Entity_Id;
f0bf2ff3 138 -- Used for Last, Last, and Length, when the prefix is an array type.
ee6ba406 139 -- Obtains the corresponding index subtype.
140
1550b445 141 procedure Find_Fat_Info
142 (T : Entity_Id;
143 Fat_Type : out Entity_Id;
144 Fat_Pkg : out RE_Id);
145 -- Given a floating-point type T, identifies the package containing the
146 -- attributes for this type (returned in Fat_Pkg), and the corresponding
147 -- type for which this package was instantiated from Fat_Gen. Error if T
148 -- is not a floating-point type.
149
9dfe12ae 150 function Find_Stream_Subprogram
151 (Typ : Entity_Id;
152 Nam : TSS_Name_Type) return Entity_Id;
153 -- Returns the stream-oriented subprogram attribute for Typ. For tagged
154 -- types, the corresponding primitive operation is looked up, else the
155 -- appropriate TSS from the type itself, or from its closest ancestor
156 -- defining it, is returned. In both cases, inheritance of representation
157 -- aspects is thus taken into account.
ee6ba406 158
5245b786 159 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id;
160 -- Given a type, find a corresponding stream convert pragma that applies to
161 -- the implementation base type of this type (Typ). If found, return the
162 -- pragma node, otherwise return Empty if no pragma is found.
163
ee6ba406 164 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean;
165 -- Utility for array attributes, returns true on packed constrained
166 -- arrays, and on access to same.
167
99f2248e 168 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean;
169 -- Returns true iff the given node refers to an attribute call that
170 -- can be expanded directly by the back end and does not need front end
171 -- expansion. Typically used for rounding and truncation attributes that
172 -- appear directly inside a conversion to integer.
173
ee6ba406 174 ----------------------------------
175 -- Compile_Stream_Body_In_Scope --
176 ----------------------------------
177
178 procedure Compile_Stream_Body_In_Scope
179 (N : Node_Id;
180 Decl : Node_Id;
181 Arr : Entity_Id;
182 Check : Boolean)
183 is
184 Installed : Boolean := False;
185 Scop : constant Entity_Id := Scope (Arr);
186 Curr : constant Entity_Id := Current_Scope;
187
188 begin
189 if Is_Hidden (Arr)
190 and then not In_Open_Scopes (Scop)
191 and then Ekind (Scop) = E_Package
192 then
83aa52b6 193 Push_Scope (Scop);
ee6ba406 194 Install_Visible_Declarations (Scop);
195 Install_Private_Declarations (Scop);
196 Installed := True;
197
198 -- The entities in the package are now visible, but the generated
199 -- stream entity must appear in the current scope (usually an
200 -- enclosing stream function) so that itypes all have their proper
201 -- scopes.
202
83aa52b6 203 Push_Scope (Curr);
ee6ba406 204 end if;
205
206 if Check then
207 Insert_Action (N, Decl);
208 else
1550b445 209 Insert_Action (N, Decl, Suppress => All_Checks);
ee6ba406 210 end if;
211
212 if Installed then
213
214 -- Remove extra copy of current scope, and package itself
215
216 Pop_Scope;
217 End_Package_Scope (Scop);
218 end if;
219 end Compile_Stream_Body_In_Scope;
220
7f8eb6ed 221 -----------------------------------
222 -- Expand_Access_To_Protected_Op --
223 -----------------------------------
224
225 procedure Expand_Access_To_Protected_Op
226 (N : Node_Id;
227 Pref : Node_Id;
228 Typ : Entity_Id)
229 is
230 -- The value of the attribute_reference is a record containing two
231 -- fields: an access to the protected object, and an access to the
232 -- subprogram itself. The prefix is a selected component.
233
234 Loc : constant Source_Ptr := Sloc (N);
235 Agg : Node_Id;
236 Btyp : constant Entity_Id := Base_Type (Typ);
237 Sub : Entity_Id;
238 E_T : constant Entity_Id := Equivalent_Type (Btyp);
239 Acc : constant Entity_Id :=
240 Etype (Next_Component (First_Component (E_T)));
241 Obj_Ref : Node_Id;
242 Curr : Entity_Id;
243
244 function May_Be_External_Call return Boolean;
245 -- If the 'Access is to a local operation, but appears in a context
246 -- where it may lead to a call from outside the object, we must treat
247 -- this as an external call. Clearly we cannot tell without full
248 -- flow analysis, and a subsequent call that uses this 'Access may
249 -- lead to a bounded error (trying to seize locks twice, e.g.). For
250 -- now we treat 'Access as a potential external call if it is an actual
251 -- in a call to an outside subprogram.
252
253 --------------------------
254 -- May_Be_External_Call --
255 --------------------------
256
257 function May_Be_External_Call return Boolean is
258 Subp : Entity_Id;
d55c93e0 259 Par : Node_Id := Parent (N);
260
7f8eb6ed 261 begin
d55c93e0 262 -- Account for the case where the Access attribute is part of a
263 -- named parameter association.
264
265 if Nkind (Par) = N_Parameter_Association then
266 Par := Parent (Par);
267 end if;
268
269 if Nkind_In (Par, N_Procedure_Call_Statement, N_Function_Call)
270 and then Is_Entity_Name (Name (Par))
7f8eb6ed 271 then
d55c93e0 272 Subp := Entity (Name (Par));
7f8eb6ed 273 return not In_Open_Scopes (Scope (Subp));
274 else
275 return False;
276 end if;
277 end May_Be_External_Call;
278
279 -- Start of processing for Expand_Access_To_Protected_Op
280
281 begin
282 -- Within the body of the protected type, the prefix
283 -- designates a local operation, and the object is the first
284 -- parameter of the corresponding protected body of the
285 -- current enclosing operation.
286
287 if Is_Entity_Name (Pref) then
7f8eb6ed 288 if May_Be_External_Call then
289 Sub :=
290 New_Occurrence_Of
291 (External_Subprogram (Entity (Pref)), Loc);
292 else
293 Sub :=
294 New_Occurrence_Of
295 (Protected_Body_Subprogram (Entity (Pref)), Loc);
296 end if;
297
d55c93e0 298 -- Don't traverse the scopes when the attribute occurs within an init
299 -- proc, because we directly use the _init formal of the init proc in
300 -- that case.
301
7f8eb6ed 302 Curr := Current_Scope;
d55c93e0 303 if not Is_Init_Proc (Curr) then
304 pragma Assert (In_Open_Scopes (Scope (Entity (Pref))));
305
306 while Scope (Curr) /= Scope (Entity (Pref)) loop
307 Curr := Scope (Curr);
308 end loop;
309 end if;
7f8eb6ed 310
311 -- In case of protected entries the first formal of its Protected_
312 -- Body_Subprogram is the address of the object.
313
314 if Ekind (Curr) = E_Entry then
315 Obj_Ref :=
316 New_Occurrence_Of
317 (First_Formal
318 (Protected_Body_Subprogram (Curr)), Loc);
319
d55c93e0 320 -- If the current scope is an init proc, then use the address of the
321 -- _init formal as the object reference.
322
323 elsif Is_Init_Proc (Curr) then
324 Obj_Ref :=
325 Make_Attribute_Reference (Loc,
326 Prefix => New_Occurrence_Of (First_Formal (Curr), Loc),
327 Attribute_Name => Name_Address);
328
7f8eb6ed 329 -- In case of protected subprograms the first formal of its
330 -- Protected_Body_Subprogram is the object and we get its address.
331
332 else
333 Obj_Ref :=
334 Make_Attribute_Reference (Loc,
335 Prefix =>
336 New_Occurrence_Of
337 (First_Formal
338 (Protected_Body_Subprogram (Curr)), Loc),
339 Attribute_Name => Name_Address);
340 end if;
341
342 -- Case where the prefix is not an entity name. Find the
343 -- version of the protected operation to be called from
344 -- outside the protected object.
345
346 else
347 Sub :=
348 New_Occurrence_Of
349 (External_Subprogram
350 (Entity (Selector_Name (Pref))), Loc);
351
352 Obj_Ref :=
353 Make_Attribute_Reference (Loc,
354 Prefix => Relocate_Node (Prefix (Pref)),
355 Attribute_Name => Name_Address);
356 end if;
357
358 Agg :=
359 Make_Aggregate (Loc,
360 Expressions =>
361 New_List (
362 Obj_Ref,
363 Unchecked_Convert_To (Acc,
364 Make_Attribute_Reference (Loc,
365 Prefix => Sub,
366 Attribute_Name => Name_Address))));
367
368 Rewrite (N, Agg);
369
370 Analyze_And_Resolve (N, E_T);
371
372 -- For subsequent analysis, the node must retain its type.
373 -- The backend will replace it with the equivalent type where
374 -- needed.
375
376 Set_Etype (N, Typ);
377 end Expand_Access_To_Protected_Op;
378
ee6ba406 379 --------------------------
380 -- Expand_Fpt_Attribute --
381 --------------------------
382
383 procedure Expand_Fpt_Attribute
384 (N : Node_Id;
1550b445 385 Pkg : RE_Id;
9dfe12ae 386 Nam : Name_Id;
ee6ba406 387 Args : List_Id)
388 is
389 Loc : constant Source_Ptr := Sloc (N);
390 Typ : constant Entity_Id := Etype (N);
ee6ba406 391 Fnm : Node_Id;
392
393 begin
1550b445 394 -- The function name is the selected component Attr_xxx.yyy where
395 -- Attr_xxx is the package name, and yyy is the argument Nam.
ee6ba406 396
397 -- Note: it would be more usual to have separate RE entries for each
398 -- of the entities in the Fat packages, but first they have identical
399 -- names (so we would have to have lots of renaming declarations to
400 -- meet the normal RE rule of separate names for all runtime entities),
401 -- and second there would be an awful lot of them!
402
ee6ba406 403 Fnm :=
404 Make_Selected_Component (Loc,
405 Prefix => New_Reference_To (RTE (Pkg), Loc),
9dfe12ae 406 Selector_Name => Make_Identifier (Loc, Nam));
ee6ba406 407
408 -- The generated call is given the provided set of parameters, and then
409 -- wrapped in a conversion which converts the result to the target type
5245b786 410 -- We use the base type as the target because a range check may be
411 -- required.
ee6ba406 412
413 Rewrite (N,
5245b786 414 Unchecked_Convert_To (Base_Type (Etype (N)),
ee6ba406 415 Make_Function_Call (Loc,
1550b445 416 Name => Fnm,
ee6ba406 417 Parameter_Associations => Args)));
418
419 Analyze_And_Resolve (N, Typ);
ee6ba406 420 end Expand_Fpt_Attribute;
421
422 ----------------------------
423 -- Expand_Fpt_Attribute_R --
424 ----------------------------
425
426 -- The single argument is converted to its root type to call the
427 -- appropriate runtime function, with the actual call being built
428 -- by Expand_Fpt_Attribute
429
430 procedure Expand_Fpt_Attribute_R (N : Node_Id) is
431 E1 : constant Node_Id := First (Expressions (N));
1550b445 432 Ftp : Entity_Id;
433 Pkg : RE_Id;
ee6ba406 434 begin
1550b445 435 Find_Fat_Info (Etype (E1), Ftp, Pkg);
9dfe12ae 436 Expand_Fpt_Attribute
1550b445 437 (N, Pkg, Attribute_Name (N),
438 New_List (Unchecked_Convert_To (Ftp, Relocate_Node (E1))));
ee6ba406 439 end Expand_Fpt_Attribute_R;
440
441 -----------------------------
442 -- Expand_Fpt_Attribute_RI --
443 -----------------------------
444
445 -- The first argument is converted to its root type and the second
446 -- argument is converted to standard long long integer to call the
447 -- appropriate runtime function, with the actual call being built
448 -- by Expand_Fpt_Attribute
449
450 procedure Expand_Fpt_Attribute_RI (N : Node_Id) is
451 E1 : constant Node_Id := First (Expressions (N));
1550b445 452 Ftp : Entity_Id;
453 Pkg : RE_Id;
ee6ba406 454 E2 : constant Node_Id := Next (E1);
ee6ba406 455 begin
1550b445 456 Find_Fat_Info (Etype (E1), Ftp, Pkg);
9dfe12ae 457 Expand_Fpt_Attribute
1550b445 458 (N, Pkg, Attribute_Name (N),
9dfe12ae 459 New_List (
1550b445 460 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
9dfe12ae 461 Unchecked_Convert_To (Standard_Integer, Relocate_Node (E2))));
ee6ba406 462 end Expand_Fpt_Attribute_RI;
463
464 -----------------------------
465 -- Expand_Fpt_Attribute_RR --
466 -----------------------------
467
99f2248e 468 -- The two arguments are converted to their root types to call the
ee6ba406 469 -- appropriate runtime function, with the actual call being built
470 -- by Expand_Fpt_Attribute
471
472 procedure Expand_Fpt_Attribute_RR (N : Node_Id) is
473 E1 : constant Node_Id := First (Expressions (N));
1550b445 474 Ftp : Entity_Id;
475 Pkg : RE_Id;
ee6ba406 476 E2 : constant Node_Id := Next (E1);
ee6ba406 477 begin
1550b445 478 Find_Fat_Info (Etype (E1), Ftp, Pkg);
9dfe12ae 479 Expand_Fpt_Attribute
1550b445 480 (N, Pkg, Attribute_Name (N),
9dfe12ae 481 New_List (
1550b445 482 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
483 Unchecked_Convert_To (Ftp, Relocate_Node (E2))));
ee6ba406 484 end Expand_Fpt_Attribute_RR;
485
486 ----------------------------------
487 -- Expand_N_Attribute_Reference --
488 ----------------------------------
489
490 procedure Expand_N_Attribute_Reference (N : Node_Id) is
491 Loc : constant Source_Ptr := Sloc (N);
492 Typ : constant Entity_Id := Etype (N);
493 Btyp : constant Entity_Id := Base_Type (Typ);
494 Pref : constant Node_Id := Prefix (N);
d55c93e0 495 Ptyp : constant Entity_Id := Etype (Pref);
ee6ba406 496 Exprs : constant List_Id := Expressions (N);
497 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
498
499 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id);
500 -- Rewrites a stream attribute for Read, Write or Output with the
501 -- procedure call. Pname is the entity for the procedure to call.
502
503 ------------------------------
504 -- Rewrite_Stream_Proc_Call --
505 ------------------------------
506
507 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id) is
508 Item : constant Node_Id := Next (First (Exprs));
9dfe12ae 509 Formal : constant Entity_Id := Next_Formal (First_Formal (Pname));
510 Formal_Typ : constant Entity_Id := Etype (Formal);
511 Is_Written : constant Boolean := (Ekind (Formal) /= E_In_Parameter);
ee6ba406 512
513 begin
9dfe12ae 514 -- The expansion depends on Item, the second actual, which is
515 -- the object being streamed in or out.
516
517 -- If the item is a component of a packed array type, and
518 -- a conversion is needed on exit, we introduce a temporary to
519 -- hold the value, because otherwise the packed reference will
520 -- not be properly expanded.
521
522 if Nkind (Item) = N_Indexed_Component
523 and then Is_Packed (Base_Type (Etype (Prefix (Item))))
524 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
525 and then Is_Written
526 then
527 declare
528 Temp : constant Entity_Id :=
529 Make_Defining_Identifier
530 (Loc, New_Internal_Name ('V'));
531 Decl : Node_Id;
532 Assn : Node_Id;
533
534 begin
535 Decl :=
536 Make_Object_Declaration (Loc,
537 Defining_Identifier => Temp,
538 Object_Definition =>
539 New_Occurrence_Of (Formal_Typ, Loc));
540 Set_Etype (Temp, Formal_Typ);
541
542 Assn :=
543 Make_Assignment_Statement (Loc,
544 Name => New_Copy_Tree (Item),
545 Expression =>
546 Unchecked_Convert_To
547 (Etype (Item), New_Occurrence_Of (Temp, Loc)));
548
549 Rewrite (Item, New_Occurrence_Of (Temp, Loc));
550 Insert_Actions (N,
551 New_List (
552 Decl,
553 Make_Procedure_Call_Statement (Loc,
554 Name => New_Occurrence_Of (Pname, Loc),
555 Parameter_Associations => Exprs),
556 Assn));
557
558 Rewrite (N, Make_Null_Statement (Loc));
559 return;
560 end;
561 end if;
ee6ba406 562
563 -- For the class-wide dispatching cases, and for cases in which
564 -- the base type of the second argument matches the base type of
9dfe12ae 565 -- the corresponding formal parameter (that is to say the stream
566 -- operation is not inherited), we are all set, and can use the
567 -- argument unchanged.
ee6ba406 568
569 -- For all other cases we do an unchecked conversion of the second
570 -- parameter to the type of the formal of the procedure we are
571 -- calling. This deals with the private type cases, and with going
572 -- to the root type as required in elementary type case.
573
574 if not Is_Class_Wide_Type (Entity (Pref))
9dfe12ae 575 and then not Is_Class_Wide_Type (Etype (Item))
ee6ba406 576 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
577 then
578 Rewrite (Item,
579 Unchecked_Convert_To (Formal_Typ, Relocate_Node (Item)));
580
581 -- For untagged derived types set Assignment_OK, to prevent
582 -- copies from being created when the unchecked conversion
583 -- is expanded (which would happen in Remove_Side_Effects
584 -- if Expand_N_Unchecked_Conversion were allowed to call
585 -- Force_Evaluation). The copy could violate Ada semantics
586 -- in cases such as an actual that is an out parameter.
587 -- Note that this approach is also used in exp_ch7 for calls
588 -- to controlled type operations to prevent problems with
589 -- actuals wrapped in unchecked conversions.
590
591 if Is_Untagged_Derivation (Etype (Expression (Item))) then
592 Set_Assignment_OK (Item);
593 end if;
594 end if;
595
596 -- And now rewrite the call
597
598 Rewrite (N,
599 Make_Procedure_Call_Statement (Loc,
600 Name => New_Occurrence_Of (Pname, Loc),
601 Parameter_Associations => Exprs));
602
603 Analyze (N);
604 end Rewrite_Stream_Proc_Call;
605
606 -- Start of processing for Expand_N_Attribute_Reference
607
608 begin
7189d17f 609 -- Do required validity checking, if enabled. Do not apply check to
610 -- output parameters of an Asm instruction, since the value of this
372ac9de 611 -- is not set till after the attribute has been elaborated, and do
612 -- not apply the check to the arguments of a 'Read or 'Input attribute
613 -- reference since the scalar argument is an OUT scalar.
ee6ba406 614
7189d17f 615 if Validity_Checks_On and then Validity_Check_Operands
616 and then Id /= Attribute_Asm_Output
372ac9de 617 and then Id /= Attribute_Read
618 and then Id /= Attribute_Input
7189d17f 619 then
ee6ba406 620 declare
621 Expr : Node_Id;
ee6ba406 622 begin
623 Expr := First (Expressions (N));
624 while Present (Expr) loop
625 Ensure_Valid (Expr);
626 Next (Expr);
627 end loop;
628 end;
629 end if;
630
d55c93e0 631 -- Ada 2005 (AI-318-02): If attribute prefix is a call to a build-in-
632 -- place function, then a temporary return object needs to be created
633 -- and access to it must be passed to the function. Currently we limit
634 -- such functions to those with inherently limited result subtypes, but
635 -- eventually we plan to expand the functions that are treated as
636 -- build-in-place to include other composite result types.
637
638 if Ada_Version >= Ada_05
639 and then Is_Build_In_Place_Function_Call (Pref)
640 then
641 Make_Build_In_Place_Call_In_Anonymous_Context (Pref);
642 end if;
643
98d58e33 644 -- If prefix is a protected type name, this is a reference to
645 -- the current instance of the type.
646
647 if Is_Protected_Self_Reference (Pref) then
648 Rewrite (Pref, Concurrent_Ref (Pref));
649 Analyze (Pref);
650 end if;
651
ee6ba406 652 -- Remaining processing depends on specific attribute
653
654 case Id is
655
656 ------------
657 -- Access --
658 ------------
659
f947f061 660 when Attribute_Access |
661 Attribute_Unchecked_Access |
662 Attribute_Unrestricted_Access =>
ee6ba406 663
5e82d8fe 664 Access_Cases : declare
5e82d8fe 665 Ref_Object : constant Node_Id := Get_Referenced_Object (Pref);
d251c56f 666 Btyp_DDT : Entity_Id;
ee6ba406 667
4094dca5 668 function Enclosing_Object (N : Node_Id) return Node_Id;
669 -- If N denotes a compound name (selected component, indexed
670 -- component, or slice), returns the name of the outermost
671 -- such enclosing object. Otherwise returns N. If the object
672 -- is a renaming, then the renamed object is returned.
673
674 ----------------------
675 -- Enclosing_Object --
676 ----------------------
677
678 function Enclosing_Object (N : Node_Id) return Node_Id is
679 Obj_Name : Node_Id;
680
681 begin
682 Obj_Name := N;
683 while Nkind_In (Obj_Name, N_Selected_Component,
684 N_Indexed_Component,
685 N_Slice)
686 loop
687 Obj_Name := Prefix (Obj_Name);
688 end loop;
689
690 return Get_Referenced_Object (Obj_Name);
691 end Enclosing_Object;
692
693 -- Local declarations
694
695 Enc_Object : constant Node_Id := Enclosing_Object (Ref_Object);
696
697 -- Start of processing for Access_Cases
698
5e82d8fe 699 begin
d251c56f 700 Btyp_DDT := Designated_Type (Btyp);
701
702 -- Handle designated types that come from the limited view
703
704 if Ekind (Btyp_DDT) = E_Incomplete_Type
705 and then From_With_Type (Btyp_DDT)
706 and then Present (Non_Limited_View (Btyp_DDT))
707 then
708 Btyp_DDT := Non_Limited_View (Btyp_DDT);
709
710 elsif Is_Class_Wide_Type (Btyp_DDT)
711 and then Ekind (Etype (Btyp_DDT)) = E_Incomplete_Type
712 and then From_With_Type (Etype (Btyp_DDT))
713 and then Present (Non_Limited_View (Etype (Btyp_DDT)))
714 and then Present (Class_Wide_Type
715 (Non_Limited_View (Etype (Btyp_DDT))))
716 then
717 Btyp_DDT :=
718 Class_Wide_Type (Non_Limited_View (Etype (Btyp_DDT)));
719 end if;
720
4c06b9d2 721 -- In order to improve the text of error messages, the designated
722 -- type of access-to-subprogram itypes is set by the semantics as
723 -- the associated subprogram entity (see sem_attr). Now we replace
724 -- such node with the proper E_Subprogram_Type itype.
725
726 if Id = Attribute_Unrestricted_Access
727 and then Is_Subprogram (Directly_Designated_Type (Typ))
728 then
d55c93e0 729 -- The following conditions ensure that this special management
4c06b9d2 730 -- is done only for "Address!(Prim'Unrestricted_Access)" nodes.
731 -- At this stage other cases in which the designated type is
732 -- still a subprogram (instead of an E_Subprogram_Type) are
526aedbb 733 -- wrong because the semantics must have overridden the type of
4c06b9d2 734 -- the node with the type imposed by the context.
735
d55c93e0 736 if Nkind (Parent (N)) = N_Unchecked_Type_Conversion
737 and then Etype (Parent (N)) = RTE (RE_Prim_Ptr)
738 then
739 Set_Etype (N, RTE (RE_Prim_Ptr));
4c06b9d2 740
d55c93e0 741 else
742 declare
743 Subp : constant Entity_Id :=
744 Directly_Designated_Type (Typ);
745 Etyp : Entity_Id;
746 Extra : Entity_Id := Empty;
747 New_Formal : Entity_Id;
748 Old_Formal : Entity_Id := First_Formal (Subp);
749 Subp_Typ : Entity_Id;
4c06b9d2 750
d55c93e0 751 begin
752 Subp_Typ := Create_Itype (E_Subprogram_Type, N);
753 Set_Etype (Subp_Typ, Etype (Subp));
754 Set_Returns_By_Ref (Subp_Typ, Returns_By_Ref (Subp));
4c06b9d2 755
d55c93e0 756 if Present (Old_Formal) then
757 New_Formal := New_Copy (Old_Formal);
758 Set_First_Entity (Subp_Typ, New_Formal);
4c06b9d2 759
d55c93e0 760 loop
761 Set_Scope (New_Formal, Subp_Typ);
762 Etyp := Etype (New_Formal);
4c06b9d2 763
d55c93e0 764 -- Handle itypes. There is no need to duplicate
765 -- here the itypes associated with record types
766 -- (i.e the implicit full view of private types).
4c06b9d2 767
d55c93e0 768 if Is_Itype (Etyp)
769 and then Ekind (Base_Type (Etyp)) /= E_Record_Type
4c06b9d2 770 then
d55c93e0 771 Extra := New_Copy (Etyp);
772 Set_Parent (Extra, New_Formal);
773 Set_Etype (New_Formal, Extra);
774 Set_Scope (Extra, Subp_Typ);
4c06b9d2 775 end if;
776
d55c93e0 777 Extra := New_Formal;
778 Next_Formal (Old_Formal);
779 exit when No (Old_Formal);
4c06b9d2 780
d55c93e0 781 Set_Next_Entity (New_Formal,
782 New_Copy (Old_Formal));
783 Next_Entity (New_Formal);
784 end loop;
4c06b9d2 785
d55c93e0 786 Set_Next_Entity (New_Formal, Empty);
787 Set_Last_Entity (Subp_Typ, Extra);
788 end if;
4c06b9d2 789
d55c93e0 790 -- Now that the explicit formals have been duplicated,
791 -- any extra formals needed by the subprogram must be
792 -- created.
4c06b9d2 793
d55c93e0 794 if Present (Extra) then
795 Set_Extra_Formal (Extra, Empty);
796 end if;
4c06b9d2 797
d55c93e0 798 Create_Extra_Formals (Subp_Typ);
799 Set_Directly_Designated_Type (Typ, Subp_Typ);
800 end;
801 end if;
4c06b9d2 802 end if;
803
5e82d8fe 804 if Is_Access_Protected_Subprogram_Type (Btyp) then
805 Expand_Access_To_Protected_Op (N, Pref, Typ);
806
807 -- If prefix is a type name, this is a reference to the current
808 -- instance of the type, within its initialization procedure.
809
810 elsif Is_Entity_Name (Pref)
811 and then Is_Type (Entity (Pref))
812 then
813 declare
814 Par : Node_Id;
815 Formal : Entity_Id;
816
817 begin
818 -- If the current instance name denotes a task type, then
819 -- the access attribute is rewritten to be the name of the
820 -- "_task" parameter associated with the task type's task
821 -- procedure. An unchecked conversion is applied to ensure
822 -- a type match in cases of expander-generated calls (e.g.
823 -- init procs).
824
825 if Is_Task_Type (Entity (Pref)) then
826 Formal :=
827 First_Entity (Get_Task_Body_Procedure (Entity (Pref)));
828 while Present (Formal) loop
829 exit when Chars (Formal) = Name_uTask;
830 Next_Entity (Formal);
831 end loop;
832
833 pragma Assert (Present (Formal));
f947f061 834
5e82d8fe 835 Rewrite (N,
836 Unchecked_Convert_To (Typ,
837 New_Occurrence_Of (Formal, Loc)));
838 Set_Etype (N, Typ);
f947f061 839
5e82d8fe 840 -- The expression must appear in a default expression,
841 -- (which in the initialization procedure is the
842 -- right-hand side of an assignment), and not in a
843 -- discriminant constraint.
f947f061 844
5e82d8fe 845 else
846 Par := Parent (N);
847 while Present (Par) loop
848 exit when Nkind (Par) = N_Assignment_Statement;
f947f061 849
5e82d8fe 850 if Nkind (Par) = N_Component_Declaration then
851 return;
852 end if;
f947f061 853
5e82d8fe 854 Par := Parent (Par);
855 end loop;
f947f061 856
5e82d8fe 857 if Present (Par) then
858 Rewrite (N,
859 Make_Attribute_Reference (Loc,
860 Prefix => Make_Identifier (Loc, Name_uInit),
861 Attribute_Name => Attribute_Name (N)));
f947f061 862
5e82d8fe 863 Analyze_And_Resolve (N, Typ);
864 end if;
f947f061 865 end if;
5e82d8fe 866 end;
867
868 -- If the prefix of an Access attribute is a dereference of an
4094dca5 869 -- access parameter (or a renaming of such a dereference, or a
870 -- subcomponent of such a dereference) and the context is a
80e22f63 871 -- general access type (including the type of an object or
872 -- component with an access_definition, but not the anonymous
873 -- type of an access parameter or access discriminant), then
4094dca5 874 -- apply an accessibility check to the access parameter. We used
875 -- to rewrite the access parameter as a type conversion, but that
876 -- could only be done if the immediate prefix of the Access
877 -- attribute was the dereference, and didn't handle cases where
878 -- the attribute is applied to a subcomponent of the dereference,
879 -- since there's generally no available, appropriate access type
55dc6dc2 880 -- to convert to in that case. The attribute is passed as the
881 -- point to insert the check, because the access parameter may
882 -- come from a renaming, possibly in a different scope, and the
883 -- check must be associated with the attribute itself.
4094dca5 884
885 elsif Id = Attribute_Access
886 and then Nkind (Enc_Object) = N_Explicit_Dereference
887 and then Is_Entity_Name (Prefix (Enc_Object))
80e22f63 888 and then (Ekind (Btyp) = E_General_Access_Type
889 or else Is_Local_Anonymous_Access (Btyp))
4094dca5 890 and then Ekind (Entity (Prefix (Enc_Object))) in Formal_Kind
891 and then Ekind (Etype (Entity (Prefix (Enc_Object))))
5e82d8fe 892 = E_Anonymous_Access_Type
893 and then Present (Extra_Accessibility
4094dca5 894 (Entity (Prefix (Enc_Object))))
5e82d8fe 895 then
55dc6dc2 896 Apply_Accessibility_Check (Prefix (Enc_Object), Typ, N);
5e82d8fe 897
898 -- Ada 2005 (AI-251): If the designated type is an interface we
899 -- add an implicit conversion to force the displacement of the
900 -- pointer to reference the secondary dispatch table.
901
902 elsif Is_Interface (Btyp_DDT)
903 and then (Comes_From_Source (N)
904 or else Comes_From_Source (Ref_Object)
905 or else (Nkind (Ref_Object) in N_Has_Chars
906 and then Chars (Ref_Object) = Name_uInit))
907 then
908 if Nkind (Ref_Object) /= N_Explicit_Dereference then
909
d8d8b098 910 -- No implicit conversion required if types match, or if
911 -- the prefix is the class_wide_type of the interface. In
912 -- either case passing an object of the interface type has
913 -- already set the pointer correctly.
914
915 if Btyp_DDT = Etype (Ref_Object)
916 or else (Is_Class_Wide_Type (Etype (Ref_Object))
917 and then
918 Class_Wide_Type (Btyp_DDT) = Etype (Ref_Object))
919 then
920 null;
5e82d8fe 921
d8d8b098 922 else
5e82d8fe 923 Rewrite (Prefix (N),
d251c56f 924 Convert_To (Btyp_DDT,
5e82d8fe 925 New_Copy_Tree (Prefix (N))));
926
d251c56f 927 Analyze_And_Resolve (Prefix (N), Btyp_DDT);
ee6ba406 928 end if;
aad6babd 929
5e82d8fe 930 -- When the object is an explicit dereference, convert the
931 -- dereference's prefix.
f947f061 932
5e82d8fe 933 else
934 declare
935 Obj_DDT : constant Entity_Id :=
936 Base_Type
937 (Directly_Designated_Type
938 (Etype (Prefix (Ref_Object))));
939 begin
940 -- No implicit conversion required if designated types
941 -- match.
942
943 if Obj_DDT /= Btyp_DDT
944 and then not (Is_Class_Wide_Type (Obj_DDT)
945 and then Etype (Obj_DDT) = Btyp_DDT)
946 then
947 Rewrite (N,
948 Convert_To (Typ,
949 New_Copy_Tree (Prefix (Ref_Object))));
950 Analyze_And_Resolve (N, Typ);
951 end if;
952 end;
ee6ba406 953 end if;
5e82d8fe 954 end if;
955 end Access_Cases;
ee6ba406 956
957 --------------
958 -- Adjacent --
959 --------------
960
961 -- Transforms 'Adjacent into a call to the floating-point attribute
962 -- function Adjacent in Fat_xxx (where xxx is the root type)
963
964 when Attribute_Adjacent =>
965 Expand_Fpt_Attribute_RR (N);
966
967 -------------
968 -- Address --
969 -------------
970
971 when Attribute_Address => Address : declare
972 Task_Proc : Entity_Id;
973
974 begin
f947f061 975 -- If the prefix is a task or a task type, the useful address is that
976 -- of the procedure for the task body, i.e. the actual program unit.
977 -- We replace the original entity with that of the procedure.
ee6ba406 978
979 if Is_Entity_Name (Pref)
980 and then Is_Task_Type (Entity (Pref))
981 then
d55c93e0 982 Task_Proc := Next_Entity (Root_Type (Ptyp));
ee6ba406 983
984 while Present (Task_Proc) loop
985 exit when Ekind (Task_Proc) = E_Procedure
986 and then Etype (First_Formal (Task_Proc)) =
d55c93e0 987 Corresponding_Record_Type (Ptyp);
ee6ba406 988 Next_Entity (Task_Proc);
989 end loop;
990
991 if Present (Task_Proc) then
992 Set_Entity (Pref, Task_Proc);
993 Set_Etype (Pref, Etype (Task_Proc));
994 end if;
995
996 -- Similarly, the address of a protected operation is the address
997 -- of the corresponding protected body, regardless of the protected
998 -- object from which it is selected.
999
1000 elsif Nkind (Pref) = N_Selected_Component
1001 and then Is_Subprogram (Entity (Selector_Name (Pref)))
1002 and then Is_Protected_Type (Scope (Entity (Selector_Name (Pref))))
1003 then
1004 Rewrite (Pref,
1005 New_Occurrence_Of (
1006 External_Subprogram (Entity (Selector_Name (Pref))), Loc));
1007
1008 elsif Nkind (Pref) = N_Explicit_Dereference
d55c93e0 1009 and then Ekind (Ptyp) = E_Subprogram_Type
1010 and then Convention (Ptyp) = Convention_Protected
ee6ba406 1011 then
1012 -- The prefix is be a dereference of an access_to_protected_
1013 -- subprogram. The desired address is the second component of
1014 -- the record that represents the access.
1015
1016 declare
1017 Addr : constant Entity_Id := Etype (N);
1018 Ptr : constant Node_Id := Prefix (Pref);
1019 T : constant Entity_Id :=
1020 Equivalent_Type (Base_Type (Etype (Ptr)));
1021
1022 begin
1023 Rewrite (N,
1024 Unchecked_Convert_To (Addr,
1025 Make_Selected_Component (Loc,
1026 Prefix => Unchecked_Convert_To (T, Ptr),
1027 Selector_Name => New_Occurrence_Of (
1028 Next_Entity (First_Entity (T)), Loc))));
1029
1030 Analyze_And_Resolve (N, Addr);
1031 end;
99f2248e 1032
1033 -- Ada 2005 (AI-251): Class-wide interface objects are always
1034 -- "displaced" to reference the tag associated with the interface
1035 -- type. In order to obtain the real address of such objects we
1036 -- generate a call to a run-time subprogram that returns the base
1037 -- address of the object.
1038
f0bf2ff3 1039 -- This processing is not needed in the VM case, where dispatching
1040 -- issues are taken care of by the virtual machine.
1041
d55c93e0 1042 elsif Is_Class_Wide_Type (Ptyp)
1043 and then Is_Interface (Ptyp)
662256db 1044 and then Tagged_Type_Expansion
83aa52b6 1045 and then not (Nkind (Pref) in N_Has_Entity
1046 and then Is_Subprogram (Entity (Pref)))
99f2248e 1047 then
1048 Rewrite (N,
1049 Make_Function_Call (Loc,
1050 Name => New_Reference_To (RTE (RE_Base_Address), Loc),
1051 Parameter_Associations => New_List (
1052 Relocate_Node (N))));
1053 Analyze (N);
1054 return;
ee6ba406 1055 end if;
1056
d55c93e0 1057 -- Deal with packed array reference, other cases are handled by
1058 -- the back end.
ee6ba406 1059
1060 if Involves_Packed_Array_Reference (Pref) then
1061 Expand_Packed_Address_Reference (N);
1062 end if;
1063 end Address;
1064
9dfe12ae 1065 ---------------
1066 -- Alignment --
1067 ---------------
1068
1069 when Attribute_Alignment => Alignment : declare
9dfe12ae 1070 New_Node : Node_Id;
1071
1072 begin
1073 -- For class-wide types, X'Class'Alignment is transformed into a
1074 -- direct reference to the Alignment of the class type, so that the
1075 -- back end does not have to deal with the X'Class'Alignment
1076 -- reference.
1077
1078 if Is_Entity_Name (Pref)
1079 and then Is_Class_Wide_Type (Entity (Pref))
1080 then
1081 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
1082 return;
1083
1084 -- For x'Alignment applied to an object of a class wide type,
1085 -- transform X'Alignment into a call to the predefined primitive
1086 -- operation _Alignment applied to X.
1087
1088 elsif Is_Class_Wide_Type (Ptyp) then
99f2248e 1089
1090 -- No need to do anything else compiling under restriction
1091 -- No_Dispatching_Calls. During the semantic analysis we
1092 -- already notified such violation.
1093
1094 if Restriction_Active (No_Dispatching_Calls) then
1095 return;
1096 end if;
1097
9dfe12ae 1098 New_Node :=
1099 Make_Function_Call (Loc,
1100 Name => New_Reference_To
1101 (Find_Prim_Op (Ptyp, Name_uAlignment), Loc),
1102 Parameter_Associations => New_List (Pref));
1103
1104 if Typ /= Standard_Integer then
1105
1106 -- The context is a specific integer type with which the
1107 -- original attribute was compatible. The function has a
1108 -- specific type as well, so to preserve the compatibility
1109 -- we must convert explicitly.
1110
1111 New_Node := Convert_To (Typ, New_Node);
1112 end if;
1113
1114 Rewrite (N, New_Node);
1115 Analyze_And_Resolve (N, Typ);
1116 return;
1117
1118 -- For all other cases, we just have to deal with the case of
1119 -- the fact that the result can be universal.
1120
1121 else
1122 Apply_Universal_Integer_Attribute_Checks (N);
1123 end if;
1124 end Alignment;
1125
ee6ba406 1126 ---------------
1127 -- AST_Entry --
1128 ---------------
1129
1130 when Attribute_AST_Entry => AST_Entry : declare
1131 Ttyp : Entity_Id;
1132 T_Id : Node_Id;
1133 Eent : Entity_Id;
1134
1135 Entry_Ref : Node_Id;
1136 -- The reference to the entry or entry family
1137
1138 Index : Node_Id;
1139 -- The index expression for an entry family reference, or
1140 -- the Empty if Entry_Ref references a simple entry.
1141
1142 begin
1143 if Nkind (Pref) = N_Indexed_Component then
1144 Entry_Ref := Prefix (Pref);
1145 Index := First (Expressions (Pref));
1146 else
1147 Entry_Ref := Pref;
1148 Index := Empty;
1149 end if;
1150
1151 -- Get expression for Task_Id and the entry entity
1152
1153 if Nkind (Entry_Ref) = N_Selected_Component then
1154 T_Id :=
1155 Make_Attribute_Reference (Loc,
1156 Attribute_Name => Name_Identity,
1157 Prefix => Prefix (Entry_Ref));
1158
1159 Ttyp := Etype (Prefix (Entry_Ref));
1160 Eent := Entity (Selector_Name (Entry_Ref));
1161
1162 else
1163 T_Id :=
1164 Make_Function_Call (Loc,
1165 Name => New_Occurrence_Of (RTE (RE_Current_Task), Loc));
1166
1167 Eent := Entity (Entry_Ref);
1168
1169 -- We have to find the enclosing task to get the task type
1170 -- There must be one, since we already validated this earlier
1171
1172 Ttyp := Current_Scope;
1173 while not Is_Task_Type (Ttyp) loop
1174 Ttyp := Scope (Ttyp);
1175 end loop;
1176 end if;
1177
1178 -- Now rewrite the attribute with a call to Create_AST_Handler
1179
1180 Rewrite (N,
1181 Make_Function_Call (Loc,
1182 Name => New_Occurrence_Of (RTE (RE_Create_AST_Handler), Loc),
1183 Parameter_Associations => New_List (
1184 T_Id,
1185 Entry_Index_Expression (Loc, Eent, Index, Ttyp))));
1186
1187 Analyze_And_Resolve (N, RTE (RE_AST_Handler));
1188 end AST_Entry;
1189
1190 ------------------
1191 -- Bit_Position --
1192 ------------------
1193
d55c93e0 1194 -- We compute this if a component clause was present, otherwise we leave
1195 -- the computation up to the back end, since we don't know what layout
1196 -- will be chosen.
ee6ba406 1197
1198 -- Note that the attribute can apply to a naked record component
1199 -- in generated code (i.e. the prefix is an identifier that
1200 -- references the component or discriminant entity).
1201
1202 when Attribute_Bit_Position => Bit_Position :
1203 declare
1204 CE : Entity_Id;
1205
1206 begin
1207 if Nkind (Pref) = N_Identifier then
1208 CE := Entity (Pref);
1209 else
1210 CE := Entity (Selector_Name (Pref));
1211 end if;
1212
1213 if Known_Static_Component_Bit_Offset (CE) then
1214 Rewrite (N,
1215 Make_Integer_Literal (Loc,
1216 Intval => Component_Bit_Offset (CE)));
1217 Analyze_And_Resolve (N, Typ);
1218
1219 else
1220 Apply_Universal_Integer_Attribute_Checks (N);
1221 end if;
1222 end Bit_Position;
1223
1224 ------------------
1225 -- Body_Version --
1226 ------------------
1227
1228 -- A reference to P'Body_Version or P'Version is expanded to
1229
1230 -- Vnn : Unsigned;
17953e50 1231 -- pragma Import (C, Vnn, "uuuuT");
ee6ba406 1232 -- ...
1233 -- Get_Version_String (Vnn)
1234
1235 -- where uuuu is the unit name (dots replaced by double underscore)
1236 -- and T is B for the cases of Body_Version, or Version applied to a
1237 -- subprogram acting as its own spec, and S for Version applied to a
1238 -- subprogram spec or package. This sequence of code references the
1239 -- the unsigned constant created in the main program by the binder.
1240
1241 -- A special exception occurs for Standard, where the string
7f8eb6ed 1242 -- returned is a copy of the library string in gnatvsn.ads.
ee6ba406 1243
1244 when Attribute_Body_Version | Attribute_Version => Version : declare
1245 E : constant Entity_Id :=
1246 Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
f947f061 1247 Pent : Entity_Id;
ee6ba406 1248 S : String_Id;
1249
1250 begin
1251 -- If not library unit, get to containing library unit
1252
f947f061 1253 Pent := Entity (Pref);
ee6ba406 1254 while Pent /= Standard_Standard
1255 and then Scope (Pent) /= Standard_Standard
f947f061 1256 and then not Is_Child_Unit (Pent)
ee6ba406 1257 loop
1258 Pent := Scope (Pent);
1259 end loop;
1260
f947f061 1261 -- Special case Standard and Standard.ASCII
ee6ba406 1262
f947f061 1263 if Pent = Standard_Standard or else Pent = Standard_ASCII then
ee6ba406 1264 Rewrite (N,
1265 Make_String_Literal (Loc,
5245b786 1266 Strval => Verbose_Library_Version));
ee6ba406 1267
1268 -- All other cases
1269
1270 else
1271 -- Build required string constant
1272
1273 Get_Name_String (Get_Unit_Name (Pent));
1274
1275 Start_String;
1276 for J in 1 .. Name_Len - 2 loop
1277 if Name_Buffer (J) = '.' then
1278 Store_String_Chars ("__");
1279 else
1280 Store_String_Char (Get_Char_Code (Name_Buffer (J)));
1281 end if;
1282 end loop;
1283
1284 -- Case of subprogram acting as its own spec, always use body
1285
1286 if Nkind (Declaration_Node (Pent)) in N_Subprogram_Specification
1287 and then Nkind (Parent (Declaration_Node (Pent))) =
1288 N_Subprogram_Body
1289 and then Acts_As_Spec (Parent (Declaration_Node (Pent)))
1290 then
1291 Store_String_Chars ("B");
1292
1293 -- Case of no body present, always use spec
1294
1295 elsif not Unit_Requires_Body (Pent) then
1296 Store_String_Chars ("S");
1297
1298 -- Otherwise use B for Body_Version, S for spec
1299
1300 elsif Id = Attribute_Body_Version then
1301 Store_String_Chars ("B");
1302 else
1303 Store_String_Chars ("S");
1304 end if;
1305
1306 S := End_String;
1307 Lib.Version_Referenced (S);
1308
1309 -- Insert the object declaration
1310
1311 Insert_Actions (N, New_List (
1312 Make_Object_Declaration (Loc,
1313 Defining_Identifier => E,
1314 Object_Definition =>
1315 New_Occurrence_Of (RTE (RE_Unsigned), Loc))));
1316
1317 -- Set entity as imported with correct external name
1318
1319 Set_Is_Imported (E);
1320 Set_Interface_Name (E, Make_String_Literal (Loc, S));
1321
f947f061 1322 -- Set entity as internal to ensure proper Sprint output of its
1323 -- implicit importation.
1324
1325 Set_Is_Internal (E);
1326
ee6ba406 1327 -- And now rewrite original reference
1328
1329 Rewrite (N,
1330 Make_Function_Call (Loc,
1331 Name => New_Reference_To (RTE (RE_Get_Version_String), Loc),
1332 Parameter_Associations => New_List (
1333 New_Occurrence_Of (E, Loc))));
1334 end if;
1335
1336 Analyze_And_Resolve (N, RTE (RE_Version_String));
1337 end Version;
1338
1339 -------------
1340 -- Ceiling --
1341 -------------
1342
1343 -- Transforms 'Ceiling into a call to the floating-point attribute
1344 -- function Ceiling in Fat_xxx (where xxx is the root type)
1345
1346 when Attribute_Ceiling =>
1347 Expand_Fpt_Attribute_R (N);
1348
1349 --------------
1350 -- Callable --
1351 --------------
1352
aad6babd 1353 -- Transforms 'Callable attribute into a call to the Callable function
ee6ba406 1354
1355 when Attribute_Callable => Callable :
1356 begin
1550b445 1357 -- We have an object of a task interface class-wide type as a prefix
1358 -- to Callable. Generate:
83aa52b6 1359 -- callable (Task_Id (Pref._disp_get_task_id));
1550b445 1360
1361 if Ada_Version >= Ada_05
d55c93e0 1362 and then Ekind (Ptyp) = E_Class_Wide_Type
1363 and then Is_Interface (Ptyp)
1364 and then Is_Task_Interface (Ptyp)
1550b445 1365 then
1366 Rewrite (N,
1367 Make_Function_Call (Loc,
1368 Name =>
1369 New_Reference_To (RTE (RE_Callable), Loc),
1370 Parameter_Associations => New_List (
83aa52b6 1371 Make_Unchecked_Type_Conversion (Loc,
1372 Subtype_Mark =>
1373 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
1374 Expression =>
1375 Make_Selected_Component (Loc,
1376 Prefix =>
1377 New_Copy_Tree (Pref),
1378 Selector_Name =>
1379 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
1380
1550b445 1381 else
1382 Rewrite (N,
1383 Build_Call_With_Task (Pref, RTE (RE_Callable)));
1384 end if;
1385
ee6ba406 1386 Analyze_And_Resolve (N, Standard_Boolean);
1387 end Callable;
1388
1389 ------------
1390 -- Caller --
1391 ------------
1392
1393 -- Transforms 'Caller attribute into a call to either the
1394 -- Task_Entry_Caller or the Protected_Entry_Caller function.
1395
1396 when Attribute_Caller => Caller : declare
7f9be362 1397 Id_Kind : constant Entity_Id := RTE (RO_AT_Task_Id);
9dfe12ae 1398 Ent : constant Entity_Id := Entity (Pref);
1399 Conctype : constant Entity_Id := Scope (Ent);
1400 Nest_Depth : Integer := 0;
ee6ba406 1401 Name : Node_Id;
1402 S : Entity_Id;
1403
1404 begin
1405 -- Protected case
1406
1407 if Is_Protected_Type (Conctype) then
4c06b9d2 1408 case Corresponding_Runtime_Package (Conctype) is
1409 when System_Tasking_Protected_Objects_Entries =>
1410 Name :=
1411 New_Reference_To
1412 (RTE (RE_Protected_Entry_Caller), Loc);
1413
1414 when System_Tasking_Protected_Objects_Single_Entry =>
1415 Name :=
1416 New_Reference_To
1417 (RTE (RE_Protected_Single_Entry_Caller), Loc);
1418
1419 when others =>
1420 raise Program_Error;
1421 end case;
ee6ba406 1422
1423 Rewrite (N,
1424 Unchecked_Convert_To (Id_Kind,
1425 Make_Function_Call (Loc,
1426 Name => Name,
d55c93e0 1427 Parameter_Associations => New_List (
1428 New_Reference_To
1429 (Find_Protection_Object (Current_Scope), Loc)))));
ee6ba406 1430
1431 -- Task case
1432
1433 else
1434 -- Determine the nesting depth of the E'Caller attribute, that
1435 -- is, how many accept statements are nested within the accept
1436 -- statement for E at the point of E'Caller. The runtime uses
1437 -- this depth to find the specified entry call.
1438
1439 for J in reverse 0 .. Scope_Stack.Last loop
1440 S := Scope_Stack.Table (J).Entity;
1441
1442 -- We should not reach the scope of the entry, as it should
1443 -- already have been checked in Sem_Attr that this attribute
1444 -- reference is within a matching accept statement.
1445
1446 pragma Assert (S /= Conctype);
1447
1448 if S = Ent then
1449 exit;
1450
1451 elsif Is_Entry (S) then
1452 Nest_Depth := Nest_Depth + 1;
1453 end if;
1454 end loop;
1455
1456 Rewrite (N,
1457 Unchecked_Convert_To (Id_Kind,
1458 Make_Function_Call (Loc,
d55c93e0 1459 Name =>
1460 New_Reference_To (RTE (RE_Task_Entry_Caller), Loc),
ee6ba406 1461 Parameter_Associations => New_List (
1462 Make_Integer_Literal (Loc,
1463 Intval => Int (Nest_Depth))))));
1464 end if;
1465
1466 Analyze_And_Resolve (N, Id_Kind);
1467 end Caller;
1468
1469 -------------
1470 -- Compose --
1471 -------------
1472
1473 -- Transforms 'Compose into a call to the floating-point attribute
1474 -- function Compose in Fat_xxx (where xxx is the root type)
1475
1476 -- Note: we strictly should have special code here to deal with the
1477 -- case of absurdly negative arguments (less than Integer'First)
1478 -- which will return a (signed) zero value, but it hardly seems
1479 -- worth the effort. Absurdly large positive arguments will raise
1480 -- constraint error which is fine.
1481
1482 when Attribute_Compose =>
1483 Expand_Fpt_Attribute_RI (N);
1484
1485 -----------------
1486 -- Constrained --
1487 -----------------
1488
1489 when Attribute_Constrained => Constrained : declare
1490 Formal_Ent : constant Entity_Id := Param_Entity (Pref);
1491
7f8eb6ed 1492 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean;
1493 -- Ada 2005 (AI-363): Returns True if the object name Obj denotes a
1494 -- view of an aliased object whose subtype is constrained.
1495
1496 ---------------------------------
1497 -- Is_Constrained_Aliased_View --
1498 ---------------------------------
1499
1500 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean is
1501 E : Entity_Id;
1502
1503 begin
1504 if Is_Entity_Name (Obj) then
1505 E := Entity (Obj);
1506
1507 if Present (Renamed_Object (E)) then
1508 return Is_Constrained_Aliased_View (Renamed_Object (E));
7f8eb6ed 1509 else
1510 return Is_Aliased (E) and then Is_Constrained (Etype (E));
1511 end if;
1512
1513 else
1514 return Is_Aliased_View (Obj)
1515 and then
1516 (Is_Constrained (Etype (Obj))
1517 or else (Nkind (Obj) = N_Explicit_Dereference
1518 and then
1519 not Has_Constrained_Partial_View
1520 (Base_Type (Etype (Obj)))));
1521 end if;
1522 end Is_Constrained_Aliased_View;
1523
1524 -- Start of processing for Constrained
1525
ee6ba406 1526 begin
1527 -- Reference to a parameter where the value is passed as an extra
1528 -- actual, corresponding to the extra formal referenced by the
9dfe12ae 1529 -- Extra_Constrained field of the corresponding formal. If this
1530 -- is an entry in-parameter, it is replaced by a constant renaming
1531 -- for which Extra_Constrained is never created.
ee6ba406 1532
1533 if Present (Formal_Ent)
9dfe12ae 1534 and then Ekind (Formal_Ent) /= E_Constant
ee6ba406 1535 and then Present (Extra_Constrained (Formal_Ent))
1536 then
1537 Rewrite (N,
1538 New_Occurrence_Of
1539 (Extra_Constrained (Formal_Ent), Sloc (N)));
1540
1541 -- For variables with a Extra_Constrained field, we use the
1542 -- corresponding entity.
1543
1544 elsif Nkind (Pref) = N_Identifier
1545 and then Ekind (Entity (Pref)) = E_Variable
1546 and then Present (Extra_Constrained (Entity (Pref)))
1547 then
1548 Rewrite (N,
1549 New_Occurrence_Of
1550 (Extra_Constrained (Entity (Pref)), Sloc (N)));
1551
1552 -- For all other entity names, we can tell at compile time
1553
1554 elsif Is_Entity_Name (Pref) then
1555 declare
1556 Ent : constant Entity_Id := Entity (Pref);
1557 Res : Boolean;
1558
1559 begin
1560 -- (RM J.4) obsolescent cases
1561
1562 if Is_Type (Ent) then
1563
1564 -- Private type
1565
1566 if Is_Private_Type (Ent) then
1567 Res := not Has_Discriminants (Ent)
1568 or else Is_Constrained (Ent);
1569
1570 -- It not a private type, must be a generic actual type
1571 -- that corresponded to a private type. We know that this
1572 -- correspondence holds, since otherwise the reference
1573 -- within the generic template would have been illegal.
1574
1575 else
9dfe12ae 1576 if Is_Composite_Type (Underlying_Type (Ent)) then
1577 Res := Is_Constrained (Ent);
1578 else
1579 Res := True;
1580 end if;
ee6ba406 1581 end if;
1582
1583 -- If the prefix is not a variable or is aliased, then
d55c93e0 1584 -- definitely true; if it's a formal parameter without an
1585 -- associated extra formal, then treat it as constrained.
ee6ba406 1586
7f8eb6ed 1587 -- Ada 2005 (AI-363): An aliased prefix must be known to be
1588 -- constrained in order to set the attribute to True.
1589
ee6ba406 1590 elsif not Is_Variable (Pref)
1591 or else Present (Formal_Ent)
7f8eb6ed 1592 or else (Ada_Version < Ada_05
1593 and then Is_Aliased_View (Pref))
1594 or else (Ada_Version >= Ada_05
1595 and then Is_Constrained_Aliased_View (Pref))
ee6ba406 1596 then
1597 Res := True;
1598
d55c93e0 1599 -- Variable case, look at type to see if it is constrained.
1600 -- Note that the one case where this is not accurate (the
1601 -- procedure formal case), has been handled above.
ee6ba406 1602
99f2248e 1603 -- We use the Underlying_Type here (and below) in case the
1604 -- type is private without discriminants, but the full type
1605 -- has discriminants. This case is illegal, but we generate it
1606 -- internally for passing to the Extra_Constrained parameter.
1607
ee6ba406 1608 else
99f2248e 1609 Res := Is_Constrained (Underlying_Type (Etype (Ent)));
ee6ba406 1610 end if;
1611
1bbc9831 1612 Rewrite (N,
1613 New_Reference_To (Boolean_Literals (Res), Loc));
ee6ba406 1614 end;
1615
d55c93e0 1616 -- Prefix is not an entity name. These are also cases where we can
1617 -- always tell at compile time by looking at the form and type of the
1618 -- prefix. If an explicit dereference of an object with constrained
1619 -- partial view, this is unconstrained (Ada 2005 AI-363).
ee6ba406 1620
1621 else
1bbc9831 1622 Rewrite (N,
1623 New_Reference_To (
1624 Boolean_Literals (
1625 not Is_Variable (Pref)
aad6babd 1626 or else
1627 (Nkind (Pref) = N_Explicit_Dereference
1628 and then
d55c93e0 1629 not Has_Constrained_Partial_View (Base_Type (Ptyp)))
1630 or else Is_Constrained (Underlying_Type (Ptyp))),
1bbc9831 1631 Loc));
ee6ba406 1632 end if;
1633
1634 Analyze_And_Resolve (N, Standard_Boolean);
1635 end Constrained;
1636
1637 ---------------
1638 -- Copy_Sign --
1639 ---------------
1640
1641 -- Transforms 'Copy_Sign into a call to the floating-point attribute
1642 -- function Copy_Sign in Fat_xxx (where xxx is the root type)
1643
1644 when Attribute_Copy_Sign =>
1645 Expand_Fpt_Attribute_RR (N);
1646
1647 -----------
1648 -- Count --
1649 -----------
1650
1651 -- Transforms 'Count attribute into a call to the Count function
1652
d55c93e0 1653 when Attribute_Count => Count : declare
1654 Call : Node_Id;
1655 Conctyp : Entity_Id;
1656 Entnam : Node_Id;
1657 Entry_Id : Entity_Id;
1658 Index : Node_Id;
1659 Name : Node_Id;
ee6ba406 1660
1661 begin
1662 -- If the prefix is a member of an entry family, retrieve both
1663 -- entry name and index. For a simple entry there is no index.
1664
1665 if Nkind (Pref) = N_Indexed_Component then
1666 Entnam := Prefix (Pref);
1667 Index := First (Expressions (Pref));
1668 else
1669 Entnam := Pref;
1670 Index := Empty;
1671 end if;
1672
d55c93e0 1673 Entry_Id := Entity (Entnam);
1674
ee6ba406 1675 -- Find the concurrent type in which this attribute is referenced
1676 -- (there had better be one).
1677
1678 Conctyp := Current_Scope;
1679 while not Is_Concurrent_Type (Conctyp) loop
1680 Conctyp := Scope (Conctyp);
1681 end loop;
1682
1683 -- Protected case
1684
1685 if Is_Protected_Type (Conctyp) then
4c06b9d2 1686 case Corresponding_Runtime_Package (Conctyp) is
1687 when System_Tasking_Protected_Objects_Entries =>
1688 Name := New_Reference_To (RTE (RE_Protected_Count), Loc);
1689
1690 Call :=
1691 Make_Function_Call (Loc,
1692 Name => Name,
1693 Parameter_Associations => New_List (
d55c93e0 1694 New_Reference_To
1695 (Find_Protection_Object (Current_Scope), Loc),
1696 Entry_Index_Expression
1697 (Loc, Entry_Id, Index, Scope (Entry_Id))));
4c06b9d2 1698
1699 when System_Tasking_Protected_Objects_Single_Entry =>
d55c93e0 1700 Name :=
1701 New_Reference_To (RTE (RE_Protected_Count_Entry), Loc);
4c06b9d2 1702
1703 Call :=
1704 Make_Function_Call (Loc,
1705 Name => Name,
1706 Parameter_Associations => New_List (
d55c93e0 1707 New_Reference_To
1708 (Find_Protection_Object (Current_Scope), Loc)));
1709
4c06b9d2 1710 when others =>
1711 raise Program_Error;
4c06b9d2 1712 end case;
ee6ba406 1713
1714 -- Task case
1715
1716 else
1717 Call :=
1718 Make_Function_Call (Loc,
1719 Name => New_Reference_To (RTE (RE_Task_Count), Loc),
1720 Parameter_Associations => New_List (
d55c93e0 1721 Entry_Index_Expression (Loc,
1722 Entry_Id, Index, Scope (Entry_Id))));
ee6ba406 1723 end if;
1724
1725 -- The call returns type Natural but the context is universal integer
1726 -- so any integer type is allowed. The attribute was already resolved
1727 -- so its Etype is the required result type. If the base type of the
1728 -- context type is other than Standard.Integer we put in a conversion
1729 -- to the required type. This can be a normal typed conversion since
1730 -- both input and output types of the conversion are integer types
1731
1732 if Base_Type (Typ) /= Base_Type (Standard_Integer) then
1733 Rewrite (N, Convert_To (Typ, Call));
1734 else
1735 Rewrite (N, Call);
1736 end if;
1737
1738 Analyze_And_Resolve (N, Typ);
1739 end Count;
1740
1741 ---------------
1742 -- Elab_Body --
1743 ---------------
1744
1745 -- This processing is shared by Elab_Spec
1746
1747 -- What we do is to insert the following declarations
1748
1749 -- procedure tnn;
1750 -- pragma Import (C, enn, "name___elabb/s");
1751
1752 -- and then the Elab_Body/Spec attribute is replaced by a reference
1753 -- to this defining identifier.
1754
1755 when Attribute_Elab_Body |
1756 Attribute_Elab_Spec =>
1757
1758 Elab_Body : declare
1759 Ent : constant Entity_Id :=
1760 Make_Defining_Identifier (Loc,
1761 New_Internal_Name ('E'));
1762 Str : String_Id;
1763 Lang : Node_Id;
1764
1765 procedure Make_Elab_String (Nod : Node_Id);
1766 -- Given Nod, an identifier, or a selected component, put the
1767 -- image into the current string literal, with double underline
1768 -- between components.
1769
7f8eb6ed 1770 ----------------------
1771 -- Make_Elab_String --
1772 ----------------------
1773
ee6ba406 1774 procedure Make_Elab_String (Nod : Node_Id) is
1775 begin
1776 if Nkind (Nod) = N_Selected_Component then
1777 Make_Elab_String (Prefix (Nod));
7f8eb6ed 1778
83aa52b6 1779 case VM_Target is
1780 when JVM_Target =>
1781 Store_String_Char ('$');
1782 when CLI_Target =>
1783 Store_String_Char ('.');
1784 when No_VM =>
1785 Store_String_Char ('_');
1786 Store_String_Char ('_');
1787 end case;
ee6ba406 1788
1789 Get_Name_String (Chars (Selector_Name (Nod)));
1790
1791 else
1792 pragma Assert (Nkind (Nod) = N_Identifier);
1793 Get_Name_String (Chars (Nod));
1794 end if;
1795
1796 Store_String_Chars (Name_Buffer (1 .. Name_Len));
1797 end Make_Elab_String;
1798
1799 -- Start of processing for Elab_Body/Elab_Spec
1800
1801 begin
1802 -- First we need to prepare the string literal for the name of
1803 -- the elaboration routine to be referenced.
1804
1805 Start_String;
1806 Make_Elab_String (Pref);
1807
83aa52b6 1808 if VM_Target = No_VM then
ee6ba406 1809 Store_String_Chars ("___elab");
1810 Lang := Make_Identifier (Loc, Name_C);
83aa52b6 1811 else
1812 Store_String_Chars ("._elab");
1813 Lang := Make_Identifier (Loc, Name_Ada);
ee6ba406 1814 end if;
1815
1816 if Id = Attribute_Elab_Body then
1817 Store_String_Char ('b');
1818 else
1819 Store_String_Char ('s');
1820 end if;
1821
1822 Str := End_String;
1823
1824 Insert_Actions (N, New_List (
1825 Make_Subprogram_Declaration (Loc,
1826 Specification =>
1827 Make_Procedure_Specification (Loc,
1828 Defining_Unit_Name => Ent)),
1829
1830 Make_Pragma (Loc,
1831 Chars => Name_Import,
1832 Pragma_Argument_Associations => New_List (
1833 Make_Pragma_Argument_Association (Loc,
1834 Expression => Lang),
1835
1836 Make_Pragma_Argument_Association (Loc,
1837 Expression =>
1838 Make_Identifier (Loc, Chars (Ent))),
1839
1840 Make_Pragma_Argument_Association (Loc,
1841 Expression =>
1842 Make_String_Literal (Loc, Str))))));
1843
1844 Set_Entity (N, Ent);
1845 Rewrite (N, New_Occurrence_Of (Ent, Loc));
1846 end Elab_Body;
1847
1848 ----------------
1849 -- Elaborated --
1850 ----------------
1851
d55c93e0 1852 -- Elaborated is always True for preelaborated units, predefined units,
1853 -- pure units and units which have Elaborate_Body pragmas. These units
1854 -- have no elaboration entity.
ee6ba406 1855
d55c93e0 1856 -- Note: The Elaborated attribute is never passed to the back end
ee6ba406 1857
1858 when Attribute_Elaborated => Elaborated : declare
1859 Ent : constant Entity_Id := Entity (Pref);
1860
1861 begin
1862 if Present (Elaboration_Entity (Ent)) then
1863 Rewrite (N,
1864 New_Occurrence_Of (Elaboration_Entity (Ent), Loc));
1865 else
1866 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
1867 end if;
1868 end Elaborated;
1869
1870 --------------
1871 -- Enum_Rep --
1872 --------------
1873
1874 when Attribute_Enum_Rep => Enum_Rep :
1875 begin
1876 -- X'Enum_Rep (Y) expands to
1877
1878 -- target-type (Y)
1879
d55c93e0 1880 -- This is simply a direct conversion from the enumeration type to
1881 -- the target integer type, which is treated by the back end as a
1882 -- normal integer conversion, treating the enumeration type as an
1883 -- integer, which is exactly what we want! We set Conversion_OK to
1884 -- make sure that the analyzer does not complain about what otherwise
1885 -- might be an illegal conversion.
ee6ba406 1886
1887 if Is_Non_Empty_List (Exprs) then
1888 Rewrite (N,
1889 OK_Convert_To (Typ, Relocate_Node (First (Exprs))));
1890
1891 -- X'Enum_Rep where X is an enumeration literal is replaced by
1892 -- the literal value.
1893
1894 elsif Ekind (Entity (Pref)) = E_Enumeration_Literal then
1895 Rewrite (N,
1896 Make_Integer_Literal (Loc, Enumeration_Rep (Entity (Pref))));
1897
9dfe12ae 1898 -- If this is a renaming of a literal, recover the representation
1899 -- of the original.
1900
1901 elsif Ekind (Entity (Pref)) = E_Constant
1902 and then Present (Renamed_Object (Entity (Pref)))
1903 and then
1904 Ekind (Entity (Renamed_Object (Entity (Pref))))
1905 = E_Enumeration_Literal
1906 then
1907 Rewrite (N,
1908 Make_Integer_Literal (Loc,
1909 Enumeration_Rep (Entity (Renamed_Object (Entity (Pref))))));
1910
ee6ba406 1911 -- X'Enum_Rep where X is an object does a direct unchecked conversion
1912 -- of the object value, as described for the type case above.
1913
1914 else
1915 Rewrite (N,
1916 OK_Convert_To (Typ, Relocate_Node (Pref)));
1917 end if;
1918
1919 Set_Etype (N, Typ);
1920 Analyze_And_Resolve (N, Typ);
ee6ba406 1921 end Enum_Rep;
1922
d55c93e0 1923 --------------
1924 -- Enum_Val --
1925 --------------
1926
1927 when Attribute_Enum_Val => Enum_Val : declare
1928 Expr : Node_Id;
1929 Btyp : constant Entity_Id := Base_Type (Ptyp);
1930
1931 begin
1932 -- X'Enum_Val (Y) expands to
1933
1934 -- [constraint_error when _rep_to_pos (Y, False) = -1, msg]
1935 -- X!(Y);
1936
1937 Expr := Unchecked_Convert_To (Ptyp, First (Exprs));
1938
1939 Insert_Action (N,
1940 Make_Raise_Constraint_Error (Loc,
1941 Condition =>
1942 Make_Op_Eq (Loc,
1943 Left_Opnd =>
1944 Make_Function_Call (Loc,
1945 Name =>
1946 New_Reference_To (TSS (Btyp, TSS_Rep_To_Pos), Loc),
1947 Parameter_Associations => New_List (
1948 Relocate_Node (Duplicate_Subexpr (Expr)),
1949 New_Occurrence_Of (Standard_False, Loc))),
1950
1951 Right_Opnd => Make_Integer_Literal (Loc, -1)),
1952 Reason => CE_Range_Check_Failed));
1953
1954 Rewrite (N, Expr);
1955 Analyze_And_Resolve (N, Ptyp);
1956 end Enum_Val;
1957
ee6ba406 1958 --------------
1959 -- Exponent --
1960 --------------
1961
1962 -- Transforms 'Exponent into a call to the floating-point attribute
1963 -- function Exponent in Fat_xxx (where xxx is the root type)
1964
1965 when Attribute_Exponent =>
1966 Expand_Fpt_Attribute_R (N);
1967
1968 ------------------
1969 -- External_Tag --
1970 ------------------
1971
1972 -- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag)
1973
1974 when Attribute_External_Tag => External_Tag :
1975 begin
1976 Rewrite (N,
1977 Make_Function_Call (Loc,
1978 Name => New_Reference_To (RTE (RE_External_Tag), Loc),
1979 Parameter_Associations => New_List (
1980 Make_Attribute_Reference (Loc,
1981 Attribute_Name => Name_Tag,
1982 Prefix => Prefix (N)))));
1983
1984 Analyze_And_Resolve (N, Standard_String);
1985 end External_Tag;
1986
1987 -----------
1988 -- First --
1989 -----------
1990
d55c93e0 1991 when Attribute_First =>
ee6ba406 1992
ee6ba406 1993 -- If the prefix type is a constrained packed array type which
1994 -- already has a Packed_Array_Type representation defined, then
1995 -- replace this attribute with a direct reference to 'First of the
d55c93e0 1996 -- appropriate index subtype (since otherwise the back end will try
1997 -- to give us the value of 'First for this implementation type).
ee6ba406 1998
1999 if Is_Constrained_Packed_Array (Ptyp) then
2000 Rewrite (N,
2001 Make_Attribute_Reference (Loc,
2002 Attribute_Name => Name_First,
2003 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
2004 Analyze_And_Resolve (N, Typ);
2005
2006 elsif Is_Access_Type (Ptyp) then
2007 Apply_Access_Check (N);
2008 end if;
ee6ba406 2009
2010 ---------------
2011 -- First_Bit --
2012 ---------------
2013
d55c93e0 2014 -- Compute this if component clause was present, otherwise we leave the
2015 -- computation to be completed in the back-end, since we don't know what
ee6ba406 2016 -- layout will be chosen.
2017
d55c93e0 2018 when Attribute_First_Bit => First_Bit : declare
ee6ba406 2019 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2020
2021 begin
2022 if Known_Static_Component_Bit_Offset (CE) then
2023 Rewrite (N,
2024 Make_Integer_Literal (Loc,
2025 Component_Bit_Offset (CE) mod System_Storage_Unit));
2026
2027 Analyze_And_Resolve (N, Typ);
2028
2029 else
2030 Apply_Universal_Integer_Attribute_Checks (N);
2031 end if;
2032 end First_Bit;
2033
2034 -----------------
2035 -- Fixed_Value --
2036 -----------------
2037
2038 -- We transform:
2039
2040 -- fixtype'Fixed_Value (integer-value)
2041
2042 -- into
2043
2044 -- fixtype(integer-value)
2045
d55c93e0 2046 -- We do all the required analysis of the conversion here, because we do
2047 -- not want this to go through the fixed-point conversion circuits. Note
2048 -- that the back end always treats fixed-point as equivalent to the
2049 -- corresponding integer type anyway.
ee6ba406 2050
2051 when Attribute_Fixed_Value => Fixed_Value :
2052 begin
2053 Rewrite (N,
2054 Make_Type_Conversion (Loc,
2055 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2056 Expression => Relocate_Node (First (Exprs))));
2057 Set_Etype (N, Entity (Pref));
2058 Set_Analyzed (N);
9dfe12ae 2059
2060 -- Note: it might appear that a properly analyzed unchecked conversion
2061 -- would be just fine here, but that's not the case, since the full
2062 -- range checks performed by the following call are critical!
2063
ee6ba406 2064 Apply_Type_Conversion_Checks (N);
2065 end Fixed_Value;
2066
2067 -----------
2068 -- Floor --
2069 -----------
2070
2071 -- Transforms 'Floor into a call to the floating-point attribute
2072 -- function Floor in Fat_xxx (where xxx is the root type)
2073
2074 when Attribute_Floor =>
2075 Expand_Fpt_Attribute_R (N);
2076
2077 ----------
2078 -- Fore --
2079 ----------
2080
2081 -- For the fixed-point type Typ:
2082
2083 -- Typ'Fore
2084
2085 -- expands into
2086
1550b445 2087 -- Result_Type (System.Fore (Universal_Real (Type'First)),
2088 -- Universal_Real (Type'Last))
ee6ba406 2089
2090 -- Note that we know that the type is a non-static subtype, or Fore
2091 -- would have itself been computed dynamically in Eval_Attribute.
2092
d55c93e0 2093 when Attribute_Fore => Fore : begin
ee6ba406 2094 Rewrite (N,
2095 Convert_To (Typ,
2096 Make_Function_Call (Loc,
2097 Name => New_Reference_To (RTE (RE_Fore), Loc),
2098
2099 Parameter_Associations => New_List (
1550b445 2100 Convert_To (Universal_Real,
ee6ba406 2101 Make_Attribute_Reference (Loc,
2102 Prefix => New_Reference_To (Ptyp, Loc),
2103 Attribute_Name => Name_First)),
2104
1550b445 2105 Convert_To (Universal_Real,
ee6ba406 2106 Make_Attribute_Reference (Loc,
2107 Prefix => New_Reference_To (Ptyp, Loc),
2108 Attribute_Name => Name_Last))))));
2109
2110 Analyze_And_Resolve (N, Typ);
2111 end Fore;
2112
2113 --------------
2114 -- Fraction --
2115 --------------
2116
2117 -- Transforms 'Fraction into a call to the floating-point attribute
2118 -- function Fraction in Fat_xxx (where xxx is the root type)
2119
2120 when Attribute_Fraction =>
2121 Expand_Fpt_Attribute_R (N);
2122
5690e662 2123 --------------
2124 -- From_Any --
2125 --------------
2126
2127 when Attribute_From_Any => From_Any : declare
2128 P_Type : constant Entity_Id := Etype (Pref);
2129 Decls : constant List_Id := New_List;
2130 begin
2131 Rewrite (N,
2132 Build_From_Any_Call (P_Type,
2133 Relocate_Node (First (Exprs)),
2134 Decls));
2135 Insert_Actions (N, Decls);
2136 Analyze_And_Resolve (N, P_Type);
2137 end From_Any;
2138
ee6ba406 2139 --------------
2140 -- Identity --
2141 --------------
2142
2143 -- For an exception returns a reference to the exception data:
2144 -- Exception_Id!(Prefix'Reference)
2145
2146 -- For a task it returns a reference to the _task_id component of
2147 -- corresponding record:
2148
7f9be362 2149 -- taskV!(Prefix)._Task_Id, converted to the type Task_Id defined
ee6ba406 2150
aad6babd 2151 -- in Ada.Task_Identification
ee6ba406 2152
2153 when Attribute_Identity => Identity : declare
2154 Id_Kind : Entity_Id;
2155
2156 begin
d55c93e0 2157 if Ptyp = Standard_Exception_Type then
ee6ba406 2158 Id_Kind := RTE (RE_Exception_Id);
2159
2160 if Present (Renamed_Object (Entity (Pref))) then
2161 Set_Entity (Pref, Renamed_Object (Entity (Pref)));
2162 end if;
2163
2164 Rewrite (N,
2165 Unchecked_Convert_To (Id_Kind, Make_Reference (Loc, Pref)));
2166 else
7f9be362 2167 Id_Kind := RTE (RO_AT_Task_Id);
ee6ba406 2168
f0bf2ff3 2169 -- If the prefix is a task interface, the Task_Id is obtained
2170 -- dynamically through a dispatching call, as for other task
2171 -- attributes applied to interfaces.
2172
2173 if Ada_Version >= Ada_05
d55c93e0 2174 and then Ekind (Ptyp) = E_Class_Wide_Type
2175 and then Is_Interface (Ptyp)
2176 and then Is_Task_Interface (Ptyp)
f0bf2ff3 2177 then
2178 Rewrite (N,
2179 Unchecked_Convert_To (Id_Kind,
2180 Make_Selected_Component (Loc,
2181 Prefix =>
2182 New_Copy_Tree (Pref),
2183 Selector_Name =>
2184 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))));
2185
2186 else
2187 Rewrite (N,
2188 Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref)));
2189 end if;
ee6ba406 2190 end if;
2191
2192 Analyze_And_Resolve (N, Id_Kind);
2193 end Identity;
2194
2195 -----------
2196 -- Image --
2197 -----------
2198
2199 -- Image attribute is handled in separate unit Exp_Imgv
2200
2201 when Attribute_Image =>
2202 Exp_Imgv.Expand_Image_Attribute (N);
2203
2204 ---------
2205 -- Img --
2206 ---------
2207
2208 -- X'Img is expanded to typ'Image (X), where typ is the type of X
2209
2210 when Attribute_Img => Img :
2211 begin
2212 Rewrite (N,
2213 Make_Attribute_Reference (Loc,
d55c93e0 2214 Prefix => New_Reference_To (Ptyp, Loc),
ee6ba406 2215 Attribute_Name => Name_Image,
2216 Expressions => New_List (Relocate_Node (Pref))));
2217
2218 Analyze_And_Resolve (N, Standard_String);
2219 end Img;
2220
2221 -----------
2222 -- Input --
2223 -----------
2224
2225 when Attribute_Input => Input : declare
2226 P_Type : constant Entity_Id := Entity (Pref);
2227 B_Type : constant Entity_Id := Base_Type (P_Type);
2228 U_Type : constant Entity_Id := Underlying_Type (P_Type);
2229 Strm : constant Node_Id := First (Exprs);
2230 Fname : Entity_Id;
2231 Decl : Node_Id;
2232 Call : Node_Id;
2233 Prag : Node_Id;
2234 Arg2 : Node_Id;
2235 Rfunc : Node_Id;
2236
2237 Cntrl : Node_Id := Empty;
2238 -- Value for controlling argument in call. Always Empty except in
2239 -- the dispatching (class-wide type) case, where it is a reference
2240 -- to the dummy object initialized to the right internal tag.
2241
d53a018a 2242 procedure Freeze_Stream_Subprogram (F : Entity_Id);
2243 -- The expansion of the attribute reference may generate a call to
2244 -- a user-defined stream subprogram that is frozen by the call. This
2245 -- can lead to access-before-elaboration problem if the reference
2246 -- appears in an object declaration and the subprogram body has not
2247 -- been seen. The freezing of the subprogram requires special code
2248 -- because it appears in an expanded context where expressions do
2249 -- not freeze their constituents.
2250
2251 ------------------------------
2252 -- Freeze_Stream_Subprogram --
2253 ------------------------------
2254
2255 procedure Freeze_Stream_Subprogram (F : Entity_Id) is
2256 Decl : constant Node_Id := Unit_Declaration_Node (F);
2257 Bod : Node_Id;
2258
2259 begin
2260 -- If this is user-defined subprogram, the corresponding
2261 -- stream function appears as a renaming-as-body, and the
2262 -- user subprogram must be retrieved by tree traversal.
2263
2264 if Present (Decl)
2265 and then Nkind (Decl) = N_Subprogram_Declaration
2266 and then Present (Corresponding_Body (Decl))
2267 then
2268 Bod := Corresponding_Body (Decl);
2269
2270 if Nkind (Unit_Declaration_Node (Bod)) =
2271 N_Subprogram_Renaming_Declaration
2272 then
2273 Set_Is_Frozen (Entity (Name (Unit_Declaration_Node (Bod))));
2274 end if;
2275 end if;
2276 end Freeze_Stream_Subprogram;
2277
2278 -- Start of processing for Input
2279
ee6ba406 2280 begin
2281 -- If no underlying type, we have an error that will be diagnosed
2282 -- elsewhere, so here we just completely ignore the expansion.
2283
2284 if No (U_Type) then
2285 return;
2286 end if;
2287
2288 -- If there is a TSS for Input, just call it
2289
9dfe12ae 2290 Fname := Find_Stream_Subprogram (P_Type, TSS_Stream_Input);
ee6ba406 2291
2292 if Present (Fname) then
2293 null;
2294
2295 else
2296 -- If there is a Stream_Convert pragma, use it, we rewrite
2297
2298 -- sourcetyp'Input (stream)
2299
2300 -- as
2301
2302 -- sourcetyp (streamread (strmtyp'Input (stream)));
2303
2c145f84 2304 -- where streamread is the given Read function that converts an
d55c93e0 2305 -- argument of type strmtyp to type sourcetyp or a type from which
2306 -- it is derived (extra conversion required for the derived case).
ee6ba406 2307
5245b786 2308 Prag := Get_Stream_Convert_Pragma (P_Type);
ee6ba406 2309
2310 if Present (Prag) then
2311 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
2312 Rfunc := Entity (Expression (Arg2));
2313
2314 Rewrite (N,
2315 Convert_To (B_Type,
2316 Make_Function_Call (Loc,
2317 Name => New_Occurrence_Of (Rfunc, Loc),
2318 Parameter_Associations => New_List (
2319 Make_Attribute_Reference (Loc,
2320 Prefix =>
2321 New_Occurrence_Of
2322 (Etype (First_Formal (Rfunc)), Loc),
2323 Attribute_Name => Name_Input,
2324 Expressions => Exprs)))));
2325
2326 Analyze_And_Resolve (N, B_Type);
2327 return;
2328
2329 -- Elementary types
2330
2331 elsif Is_Elementary_Type (U_Type) then
2332
2333 -- A special case arises if we have a defined _Read routine,
2334 -- since in this case we are required to call this routine.
2335
9dfe12ae 2336 if Present (TSS (Base_Type (U_Type), TSS_Stream_Read)) then
ee6ba406 2337 Build_Record_Or_Elementary_Input_Function
2338 (Loc, U_Type, Decl, Fname);
2339 Insert_Action (N, Decl);
2340
2341 -- For normal cases, we call the I_xxx routine directly
2342
2343 else
2344 Rewrite (N, Build_Elementary_Input_Call (N));
2345 Analyze_And_Resolve (N, P_Type);
2346 return;
2347 end if;
2348
2349 -- Array type case
2350
2351 elsif Is_Array_Type (U_Type) then
2352 Build_Array_Input_Function (Loc, U_Type, Decl, Fname);
2353 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
2354
2355 -- Dispatching case with class-wide type
2356
2357 elsif Is_Class_Wide_Type (P_Type) then
2358
99f2248e 2359 -- No need to do anything else compiling under restriction
2360 -- No_Dispatching_Calls. During the semantic analysis we
2361 -- already notified such violation.
2362
2363 if Restriction_Active (No_Dispatching_Calls) then
2364 return;
2365 end if;
2366
ee6ba406 2367 declare
2368 Rtyp : constant Entity_Id := Root_Type (P_Type);
2369 Dnn : Entity_Id;
2370 Decl : Node_Id;
2371
2372 begin
2373 -- Read the internal tag (RM 13.13.2(34)) and use it to
2374 -- initialize a dummy tag object:
2375
2376 -- Dnn : Ada.Tags.Tag
aad6babd 2377 -- := Descendant_Tag (String'Input (Strm), P_Type);
ee6ba406 2378
2379 -- This dummy object is used only to provide a controlling
aad6babd 2380 -- argument for the eventual _Input call. Descendant_Tag is
2381 -- called rather than Internal_Tag to ensure that we have a
2382 -- tag for a type that is descended from the prefix type and
2383 -- declared at the same accessibility level (the exception
2384 -- Tag_Error will be raised otherwise). The level check is
2385 -- required for Ada 2005 because tagged types can be
2386 -- extended in nested scopes (AI-344).
ee6ba406 2387
2388 Dnn :=
2389 Make_Defining_Identifier (Loc,
2390 Chars => New_Internal_Name ('D'));
2391
2392 Decl :=
2393 Make_Object_Declaration (Loc,
2394 Defining_Identifier => Dnn,
2395 Object_Definition =>
2396 New_Occurrence_Of (RTE (RE_Tag), Loc),
2397 Expression =>
2398 Make_Function_Call (Loc,
2399 Name =>
aad6babd 2400 New_Occurrence_Of (RTE (RE_Descendant_Tag), Loc),
ee6ba406 2401 Parameter_Associations => New_List (
2402 Make_Attribute_Reference (Loc,
2403 Prefix =>
2404 New_Occurrence_Of (Standard_String, Loc),
2405 Attribute_Name => Name_Input,
2406 Expressions => New_List (
2407 Relocate_Node
aad6babd 2408 (Duplicate_Subexpr (Strm)))),
2409 Make_Attribute_Reference (Loc,
2410 Prefix => New_Reference_To (P_Type, Loc),
2411 Attribute_Name => Name_Tag))));
ee6ba406 2412
2413 Insert_Action (N, Decl);
2414
2415 -- Now we need to get the entity for the call, and construct
2416 -- a function call node, where we preset a reference to Dnn
aad6babd 2417 -- as the controlling argument (doing an unchecked convert
2418 -- to the class-wide tagged type to make it look like a real
2419 -- tagged object).
ee6ba406 2420
9dfe12ae 2421 Fname := Find_Prim_Op (Rtyp, TSS_Stream_Input);
2422 Cntrl := Unchecked_Convert_To (P_Type,
ee6ba406 2423 New_Occurrence_Of (Dnn, Loc));
9dfe12ae 2424 Set_Etype (Cntrl, P_Type);
ee6ba406 2425 Set_Parent (Cntrl, N);
2426 end;
2427
2428 -- For tagged types, use the primitive Input function
2429
2430 elsif Is_Tagged_Type (U_Type) then
9dfe12ae 2431 Fname := Find_Prim_Op (U_Type, TSS_Stream_Input);
ee6ba406 2432
aad6babd 2433 -- All other record type cases, including protected records. The
2434 -- latter only arise for expander generated code for handling
2435 -- shared passive partition access.
ee6ba406 2436
2437 else
2438 pragma Assert
2439 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
2440
d55c93e0 2441 -- Ada 2005 (AI-216): Program_Error is raised executing default
2442 -- implementation of the Input attribute of an unchecked union
2443 -- type if the type lacks default discriminant values.
00f91aef 2444
2445 if Is_Unchecked_Union (Base_Type (U_Type))
18a40e97 2446 and then No (Discriminant_Constraint (U_Type))
00f91aef 2447 then
2448 Insert_Action (N,
2449 Make_Raise_Program_Error (Loc,
2450 Reason => PE_Unchecked_Union_Restriction));
2451
2452 return;
2453 end if;
2454
ee6ba406 2455 Build_Record_Or_Elementary_Input_Function
2456 (Loc, Base_Type (U_Type), Decl, Fname);
2457 Insert_Action (N, Decl);
d53a018a 2458
2459 if Nkind (Parent (N)) = N_Object_Declaration
2460 and then Is_Record_Type (U_Type)
2461 then
2462 -- The stream function may contain calls to user-defined
2463 -- Read procedures for individual components.
2464
2465 declare
2466 Comp : Entity_Id;
2467 Func : Entity_Id;
2468
2469 begin
2470 Comp := First_Component (U_Type);
2471 while Present (Comp) loop
2472 Func :=
2473 Find_Stream_Subprogram
2474 (Etype (Comp), TSS_Stream_Read);
2475
2476 if Present (Func) then
2477 Freeze_Stream_Subprogram (Func);
2478 end if;
2479
2480 Next_Component (Comp);
2481 end loop;
2482 end;
2483 end if;
ee6ba406 2484 end if;
2485 end if;
2486
aad6babd 2487 -- If we fall through, Fname is the function to be called. The result
2488 -- is obtained by calling the appropriate function, then converting
2489 -- the result. The conversion does a subtype check.
ee6ba406 2490
2491 Call :=
2492 Make_Function_Call (Loc,
2493 Name => New_Occurrence_Of (Fname, Loc),
2494 Parameter_Associations => New_List (
2495 Relocate_Node (Strm)));
2496
2497 Set_Controlling_Argument (Call, Cntrl);
2498 Rewrite (N, Unchecked_Convert_To (P_Type, Call));
2499 Analyze_And_Resolve (N, P_Type);
d53a018a 2500
2501 if Nkind (Parent (N)) = N_Object_Declaration then
2502 Freeze_Stream_Subprogram (Fname);
2503 end if;
ee6ba406 2504 end Input;
2505
2506 -------------------
2507 -- Integer_Value --
2508 -------------------
2509
2510 -- We transform
2511
2512 -- inttype'Fixed_Value (fixed-value)
2513
2514 -- into
2515
2516 -- inttype(integer-value))
2517
d55c93e0 2518 -- we do all the required analysis of the conversion here, because we do
2519 -- not want this to go through the fixed-point conversion circuits. Note
2520 -- that the back end always treats fixed-point as equivalent to the
2521 -- corresponding integer type anyway.
ee6ba406 2522
2523 when Attribute_Integer_Value => Integer_Value :
2524 begin
2525 Rewrite (N,
2526 Make_Type_Conversion (Loc,
2527 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2528 Expression => Relocate_Node (First (Exprs))));
2529 Set_Etype (N, Entity (Pref));
2530 Set_Analyzed (N);
9dfe12ae 2531
2532 -- Note: it might appear that a properly analyzed unchecked conversion
2533 -- would be just fine here, but that's not the case, since the full
2534 -- range checks performed by the following call are critical!
2535
ee6ba406 2536 Apply_Type_Conversion_Checks (N);
2537 end Integer_Value;
2538
d55c93e0 2539 -------------------
2540 -- Invalid_Value --
2541 -------------------
2542
2543 when Attribute_Invalid_Value =>
2544 Rewrite (N, Get_Simple_Init_Val (Ptyp, N));
2545
ee6ba406 2546 ----------
2547 -- Last --
2548 ----------
2549
d55c93e0 2550 when Attribute_Last =>
ee6ba406 2551
ee6ba406 2552 -- If the prefix type is a constrained packed array type which
2553 -- already has a Packed_Array_Type representation defined, then
2554 -- replace this attribute with a direct reference to 'Last of the
d55c93e0 2555 -- appropriate index subtype (since otherwise the back end will try
2556 -- to give us the value of 'Last for this implementation type).
ee6ba406 2557
2558 if Is_Constrained_Packed_Array (Ptyp) then
2559 Rewrite (N,
2560 Make_Attribute_Reference (Loc,
2561 Attribute_Name => Name_Last,
2562 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
2563 Analyze_And_Resolve (N, Typ);
2564
2565 elsif Is_Access_Type (Ptyp) then
2566 Apply_Access_Check (N);
2567 end if;
ee6ba406 2568
2569 --------------
2570 -- Last_Bit --
2571 --------------
2572
d55c93e0 2573 -- We compute this if a component clause was present, otherwise we leave
2574 -- the computation up to the back end, since we don't know what layout
2575 -- will be chosen.
ee6ba406 2576
d55c93e0 2577 when Attribute_Last_Bit => Last_Bit : declare
ee6ba406 2578 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2579
2580 begin
2581 if Known_Static_Component_Bit_Offset (CE)
2582 and then Known_Static_Esize (CE)
2583 then
2584 Rewrite (N,
2585 Make_Integer_Literal (Loc,
2586 Intval => (Component_Bit_Offset (CE) mod System_Storage_Unit)
2587 + Esize (CE) - 1));
2588
2589 Analyze_And_Resolve (N, Typ);
2590
2591 else
2592 Apply_Universal_Integer_Attribute_Checks (N);
2593 end if;
2594 end Last_Bit;
2595
2596 ------------------
2597 -- Leading_Part --
2598 ------------------
2599
2600 -- Transforms 'Leading_Part into a call to the floating-point attribute
2601 -- function Leading_Part in Fat_xxx (where xxx is the root type)
2602
d55c93e0 2603 -- Note: strictly, we should generate special case code to deal with
aad6babd 2604 -- absurdly large positive arguments (greater than Integer'Last), which
2605 -- result in returning the first argument unchanged, but it hardly seems
2606 -- worth the effort. We raise constraint error for absurdly negative
2607 -- arguments which is fine.
ee6ba406 2608
2609 when Attribute_Leading_Part =>
2610 Expand_Fpt_Attribute_RI (N);
2611
2612 ------------
2613 -- Length --
2614 ------------
2615
2616 when Attribute_Length => declare
ee6ba406 2617 Ityp : Entity_Id;
2618 Xnum : Uint;
2619
2620 begin
2621 -- Processing for packed array types
2622
2623 if Is_Array_Type (Ptyp) and then Is_Packed (Ptyp) then
2624 Ityp := Get_Index_Subtype (N);
2625
d55c93e0 2626 -- If the index type, Ityp, is an enumeration type with holes,
2627 -- then we calculate X'Length explicitly using
ee6ba406 2628
2629 -- Typ'Max
2630 -- (0, Ityp'Pos (X'Last (N)) -
2631 -- Ityp'Pos (X'First (N)) + 1);
2632
d55c93e0 2633 -- Since the bounds in the template are the representation values
2634 -- and the back end would get the wrong value.
ee6ba406 2635
2636 if Is_Enumeration_Type (Ityp)
2637 and then Present (Enum_Pos_To_Rep (Base_Type (Ityp)))
2638 then
2639 if No (Exprs) then
2640 Xnum := Uint_1;
2641 else
2642 Xnum := Expr_Value (First (Expressions (N)));
2643 end if;
2644
2645 Rewrite (N,
2646 Make_Attribute_Reference (Loc,
2647 Prefix => New_Occurrence_Of (Typ, Loc),
2648 Attribute_Name => Name_Max,
2649 Expressions => New_List
2650 (Make_Integer_Literal (Loc, 0),
2651
2652 Make_Op_Add (Loc,
2653 Left_Opnd =>
2654 Make_Op_Subtract (Loc,
2655 Left_Opnd =>
2656 Make_Attribute_Reference (Loc,
2657 Prefix => New_Occurrence_Of (Ityp, Loc),
2658 Attribute_Name => Name_Pos,
2659
2660 Expressions => New_List (
2661 Make_Attribute_Reference (Loc,
2662 Prefix => Duplicate_Subexpr (Pref),
2663 Attribute_Name => Name_Last,
2664 Expressions => New_List (
2665 Make_Integer_Literal (Loc, Xnum))))),
2666
2667 Right_Opnd =>
2668 Make_Attribute_Reference (Loc,
2669 Prefix => New_Occurrence_Of (Ityp, Loc),
2670 Attribute_Name => Name_Pos,
2671
2672 Expressions => New_List (
2673 Make_Attribute_Reference (Loc,
9dfe12ae 2674 Prefix =>
2675 Duplicate_Subexpr_No_Checks (Pref),
ee6ba406 2676 Attribute_Name => Name_First,
2677 Expressions => New_List (
2678 Make_Integer_Literal (Loc, Xnum)))))),
2679
2680 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
2681
2682 Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
2683 return;
2684
2685 -- If the prefix type is a constrained packed array type which
2686 -- already has a Packed_Array_Type representation defined, then
2687 -- replace this attribute with a direct reference to 'Range_Length
d55c93e0 2688 -- of the appropriate index subtype (since otherwise the back end
2689 -- will try to give us the value of 'Length for this
2690 -- implementation type).
ee6ba406 2691
2692 elsif Is_Constrained (Ptyp) then
2693 Rewrite (N,
2694 Make_Attribute_Reference (Loc,
2695 Attribute_Name => Name_Range_Length,
2696 Prefix => New_Reference_To (Ityp, Loc)));
2697 Analyze_And_Resolve (N, Typ);
2698 end if;
2699
ee6ba406 2700 -- Access type case
2701
2702 elsif Is_Access_Type (Ptyp) then
2703 Apply_Access_Check (N);
2704
d55c93e0 2705 -- If the designated type is a packed array type, then we convert
2706 -- the reference to:
ee6ba406 2707
2708 -- typ'Max (0, 1 +
2709 -- xtyp'Pos (Pref'Last (Expr)) -
2710 -- xtyp'Pos (Pref'First (Expr)));
2711
d55c93e0 2712 -- This is a bit complex, but it is the easiest thing to do that
2713 -- works in all cases including enum types with holes xtyp here
2714 -- is the appropriate index type.
ee6ba406 2715
2716 declare
2717 Dtyp : constant Entity_Id := Designated_Type (Ptyp);
2718 Xtyp : Entity_Id;
2719
2720 begin
2721 if Is_Array_Type (Dtyp) and then Is_Packed (Dtyp) then
2722 Xtyp := Get_Index_Subtype (N);
2723
2724 Rewrite (N,
2725 Make_Attribute_Reference (Loc,
2726 Prefix => New_Occurrence_Of (Typ, Loc),
2727 Attribute_Name => Name_Max,
2728 Expressions => New_List (
2729 Make_Integer_Literal (Loc, 0),
2730
2731 Make_Op_Add (Loc,
2732 Make_Integer_Literal (Loc, 1),
2733 Make_Op_Subtract (Loc,
2734 Left_Opnd =>
2735 Make_Attribute_Reference (Loc,
2736 Prefix => New_Occurrence_Of (Xtyp, Loc),
2737 Attribute_Name => Name_Pos,
2738 Expressions => New_List (
2739 Make_Attribute_Reference (Loc,
2740 Prefix => Duplicate_Subexpr (Pref),
2741 Attribute_Name => Name_Last,
2742 Expressions =>
2743 New_Copy_List (Exprs)))),
2744
2745 Right_Opnd =>
2746 Make_Attribute_Reference (Loc,
2747 Prefix => New_Occurrence_Of (Xtyp, Loc),
2748 Attribute_Name => Name_Pos,
2749 Expressions => New_List (
2750 Make_Attribute_Reference (Loc,
9dfe12ae 2751 Prefix =>
2752 Duplicate_Subexpr_No_Checks (Pref),
ee6ba406 2753 Attribute_Name => Name_First,
2754 Expressions =>
2755 New_Copy_List (Exprs)))))))));
2756
2757 Analyze_And_Resolve (N, Typ);
2758 end if;
2759 end;
2760
d55c93e0 2761 -- Otherwise leave it to the back end
ee6ba406 2762
2763 else
2764 Apply_Universal_Integer_Attribute_Checks (N);
2765 end if;
2766 end;
2767
2768 -------------
2769 -- Machine --
2770 -------------
2771
2772 -- Transforms 'Machine into a call to the floating-point attribute
2773 -- function Machine in Fat_xxx (where xxx is the root type)
2774
2775 when Attribute_Machine =>
2776 Expand_Fpt_Attribute_R (N);
2777
1550b445 2778 ----------------------
2779 -- Machine_Rounding --
2780 ----------------------
2781
2782 -- Transforms 'Machine_Rounding into a call to the floating-point
2783 -- attribute function Machine_Rounding in Fat_xxx (where xxx is the root
99f2248e 2784 -- type). Expansion is avoided for cases the back end can handle
2785 -- directly.
1550b445 2786
2787 when Attribute_Machine_Rounding =>
99f2248e 2788 if not Is_Inline_Floating_Point_Attribute (N) then
2789 Expand_Fpt_Attribute_R (N);
2790 end if;
1550b445 2791
ee6ba406 2792 ------------------
2793 -- Machine_Size --
2794 ------------------
2795
2796 -- Machine_Size is equivalent to Object_Size, so transform it into
d55c93e0 2797 -- Object_Size and that way the back end never sees Machine_Size.
ee6ba406 2798
2799 when Attribute_Machine_Size =>
2800 Rewrite (N,
2801 Make_Attribute_Reference (Loc,
2802 Prefix => Prefix (N),
2803 Attribute_Name => Name_Object_Size));
2804
2805 Analyze_And_Resolve (N, Typ);
2806
2807 --------------
2808 -- Mantissa --
2809 --------------
2810
aad6babd 2811 -- The only case that can get this far is the dynamic case of the old
d55c93e0 2812 -- Ada 83 Mantissa attribute for the fixed-point case. For this case,
2813 -- we expand:
ee6ba406 2814
2815 -- typ'Mantissa
2816
2817 -- into
2818
2819 -- ityp (System.Mantissa.Mantissa_Value
2820 -- (Integer'Integer_Value (typ'First),
2821 -- Integer'Integer_Value (typ'Last)));
2822
d55c93e0 2823 when Attribute_Mantissa => Mantissa : begin
ee6ba406 2824 Rewrite (N,
2825 Convert_To (Typ,
2826 Make_Function_Call (Loc,
2827 Name => New_Occurrence_Of (RTE (RE_Mantissa_Value), Loc),
2828
2829 Parameter_Associations => New_List (
2830
2831 Make_Attribute_Reference (Loc,
2832 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2833 Attribute_Name => Name_Integer_Value,
2834 Expressions => New_List (
2835
2836 Make_Attribute_Reference (Loc,
2837 Prefix => New_Occurrence_Of (Ptyp, Loc),
2838 Attribute_Name => Name_First))),
2839
2840 Make_Attribute_Reference (Loc,
2841 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2842 Attribute_Name => Name_Integer_Value,
2843 Expressions => New_List (
2844
2845 Make_Attribute_Reference (Loc,
2846 Prefix => New_Occurrence_Of (Ptyp, Loc),
2847 Attribute_Name => Name_Last)))))));
2848
2849 Analyze_And_Resolve (N, Typ);
2850 end Mantissa;
2851
18a40e97 2852 --------------------
2853 -- Mechanism_Code --
2854 --------------------
2855
2856 when Attribute_Mechanism_Code =>
2857
2858 -- We must replace the prefix in the renamed case
2859
2860 if Is_Entity_Name (Pref)
2861 and then Present (Alias (Entity (Pref)))
2862 then
2863 Set_Renamed_Subprogram (Pref, Alias (Entity (Pref)));
2864 end if;
2865
e0521a36 2866 ---------
2867 -- Mod --
2868 ---------
2869
2870 when Attribute_Mod => Mod_Case : declare
2871 Arg : constant Node_Id := Relocate_Node (First (Exprs));
2872 Hi : constant Node_Id := Type_High_Bound (Etype (Arg));
2873 Modv : constant Uint := Modulus (Btyp);
2874
2875 begin
2876
2877 -- This is not so simple. The issue is what type to use for the
2878 -- computation of the modular value.
2879
2880 -- The easy case is when the modulus value is within the bounds
2881 -- of the signed integer type of the argument. In this case we can
2882 -- just do the computation in that signed integer type, and then
2883 -- do an ordinary conversion to the target type.
2884
2885 if Modv <= Expr_Value (Hi) then
2886 Rewrite (N,
2887 Convert_To (Btyp,
2888 Make_Op_Mod (Loc,
2889 Left_Opnd => Arg,
2890 Right_Opnd => Make_Integer_Literal (Loc, Modv))));
2891
2892 -- Here we know that the modulus is larger than type'Last of the
9eb397d8 2893 -- integer type. There are two cases to consider:
e0521a36 2894
2895 -- a) The integer value is non-negative. In this case, it is
2896 -- returned as the result (since it is less than the modulus).
2897
aad6babd 2898 -- b) The integer value is negative. In this case, we know that the
2899 -- result is modulus + value, where the value might be as small as
2900 -- -modulus. The trouble is what type do we use to do the subtract.
2901 -- No type will do, since modulus can be as big as 2**64, and no
2c145f84 2902 -- integer type accommodates this value. Let's do bit of algebra
e0521a36 2903
2904 -- modulus + value
2905 -- = modulus - (-value)
2906 -- = (modulus - 1) - (-value - 1)
2907
2908 -- Now modulus - 1 is certainly in range of the modular type.
2909 -- -value is in the range 1 .. modulus, so -value -1 is in the
2910 -- range 0 .. modulus-1 which is in range of the modular type.
2911 -- Furthermore, (-value - 1) can be expressed as -(value + 1)
2912 -- which we can compute using the integer base type.
2913
9eb397d8 2914 -- Once this is done we analyze the conditional expression without
2915 -- range checks, because we know everything is in range, and we
2916 -- want to prevent spurious warnings on either branch.
2917
e0521a36 2918 else
2919 Rewrite (N,
2920 Make_Conditional_Expression (Loc,
2921 Expressions => New_List (
2922 Make_Op_Ge (Loc,
2923 Left_Opnd => Duplicate_Subexpr (Arg),
2924 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2925
2926 Convert_To (Btyp,
2927 Duplicate_Subexpr_No_Checks (Arg)),
2928
2929 Make_Op_Subtract (Loc,
2930 Left_Opnd =>
2931 Make_Integer_Literal (Loc,
2932 Intval => Modv - 1),
2933 Right_Opnd =>
2934 Convert_To (Btyp,
2935 Make_Op_Minus (Loc,
2936 Right_Opnd =>
2937 Make_Op_Add (Loc,
2938 Left_Opnd => Duplicate_Subexpr_No_Checks (Arg),
2939 Right_Opnd =>
2940 Make_Integer_Literal (Loc,
2941 Intval => 1))))))));
2942
e0521a36 2943 end if;
2944
1550b445 2945 Analyze_And_Resolve (N, Btyp, Suppress => All_Checks);
e0521a36 2946 end Mod_Case;
2947
ee6ba406 2948 -----------
2949 -- Model --
2950 -----------
2951
2952 -- Transforms 'Model into a call to the floating-point attribute
2953 -- function Model in Fat_xxx (where xxx is the root type)
2954
2955 when Attribute_Model =>
2956 Expand_Fpt_Attribute_R (N);
2957
2958 -----------------
2959 -- Object_Size --
2960 -----------------
2961
2962 -- The processing for Object_Size shares the processing for Size
2963
4c06b9d2 2964 ---------
2965 -- Old --
2966 ---------
2967
2968 when Attribute_Old => Old : declare
2969 Tnn : constant Entity_Id :=
2970 Make_Defining_Identifier (Loc,
2971 Chars => New_Internal_Name ('T'));
2972 Subp : Node_Id;
2973 Asn_Stm : Node_Id;
2974
2975 begin
d55c93e0 2976 -- Find the nearest subprogram body, ignoring _Preconditions
2977
4c06b9d2 2978 Subp := N;
2979 loop
2980 Subp := Parent (Subp);
d55c93e0 2981 exit when Nkind (Subp) = N_Subprogram_Body
2982 and then Chars (Defining_Entity (Subp)) /= Name_uPostconditions;
4c06b9d2 2983 end loop;
2984
d55c93e0 2985 -- Insert the assignment at the start of the declarations
2986
4c06b9d2 2987 Asn_Stm :=
2988 Make_Object_Declaration (Loc,
2989 Defining_Identifier => Tnn,
2990 Constant_Present => True,
2991 Object_Definition => New_Occurrence_Of (Etype (N), Loc),
2992 Expression => Pref);
2993
2994 if Is_Empty_List (Declarations (Subp)) then
2995 Set_Declarations (Subp, New_List (Asn_Stm));
2996 Analyze (Asn_Stm);
2997 else
2998 Insert_Action (First (Declarations (Subp)), Asn_Stm);
2999 end if;
3000
3001 Rewrite (N, New_Occurrence_Of (Tnn, Loc));
3002 end Old;
3003
ee6ba406 3004 ------------
3005 -- Output --
3006 ------------
3007
3008 when Attribute_Output => Output : declare
3009 P_Type : constant Entity_Id := Entity (Pref);
ee6ba406 3010 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3011 Pname : Entity_Id;
3012 Decl : Node_Id;
3013 Prag : Node_Id;
3014 Arg3 : Node_Id;
3015 Wfunc : Node_Id;
3016
3017 begin
3018 -- If no underlying type, we have an error that will be diagnosed
3019 -- elsewhere, so here we just completely ignore the expansion.
3020
3021 if No (U_Type) then
3022 return;
3023 end if;
3024
3025 -- If TSS for Output is present, just call it
3026
9dfe12ae 3027 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Output);
ee6ba406 3028
3029 if Present (Pname) then
3030 null;
3031
3032 else
3033 -- If there is a Stream_Convert pragma, use it, we rewrite
3034
3035 -- sourcetyp'Output (stream, Item)
3036
3037 -- as
3038
3039 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
3040
aad6babd 3041 -- where strmwrite is the given Write function that converts an
3042 -- argument of type sourcetyp or a type acctyp, from which it is
3043 -- derived to type strmtyp. The conversion to acttyp is required
3044 -- for the derived case.
ee6ba406 3045
5245b786 3046 Prag := Get_Stream_Convert_Pragma (P_Type);
ee6ba406 3047
3048 if Present (Prag) then
3049 Arg3 :=
3050 Next (Next (First (Pragma_Argument_Associations (Prag))));
3051 Wfunc := Entity (Expression (Arg3));
3052
3053 Rewrite (N,
3054 Make_Attribute_Reference (Loc,
3055 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
3056 Attribute_Name => Name_Output,
3057 Expressions => New_List (
3058 Relocate_Node (First (Exprs)),
3059 Make_Function_Call (Loc,
3060 Name => New_Occurrence_Of (Wfunc, Loc),
3061 Parameter_Associations => New_List (
83aa52b6 3062 OK_Convert_To (Etype (First_Formal (Wfunc)),
ee6ba406 3063 Relocate_Node (Next (First (Exprs)))))))));
3064
3065 Analyze (N);
3066 return;
3067
3068 -- For elementary types, we call the W_xxx routine directly.
3069 -- Note that the effect of Write and Output is identical for
3070 -- the case of an elementary type, since there are no
3071 -- discriminants or bounds.
3072
3073 elsif Is_Elementary_Type (U_Type) then
3074
3075 -- A special case arises if we have a defined _Write routine,
3076 -- since in this case we are required to call this routine.
3077
9dfe12ae 3078 if Present (TSS (Base_Type (U_Type), TSS_Stream_Write)) then
ee6ba406 3079 Build_Record_Or_Elementary_Output_Procedure
3080 (Loc, U_Type, Decl, Pname);
3081 Insert_Action (N, Decl);
3082
3083 -- For normal cases, we call the W_xxx routine directly
3084
3085 else
3086 Rewrite (N, Build_Elementary_Write_Call (N));
3087 Analyze (N);
3088 return;
3089 end if;
3090
3091 -- Array type case
3092
3093 elsif Is_Array_Type (U_Type) then
3094 Build_Array_Output_Procedure (Loc, U_Type, Decl, Pname);
3095 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3096
3097 -- Class-wide case, first output external tag, then dispatch
3098 -- to the appropriate primitive Output function (RM 13.13.2(31)).
3099
3100 elsif Is_Class_Wide_Type (P_Type) then
99f2248e 3101
3102 -- No need to do anything else compiling under restriction
3103 -- No_Dispatching_Calls. During the semantic analysis we
3104 -- already notified such violation.
3105
3106 if Restriction_Active (No_Dispatching_Calls) then
3107 return;
3108 end if;
3109
ee6ba406 3110 Tag_Write : declare
3111 Strm : constant Node_Id := First (Exprs);
3112 Item : constant Node_Id := Next (Strm);
3113
3114 begin
83aa52b6 3115 -- Ada 2005 (AI-344): Check that the accessibility level
3116 -- of the type of the output object is not deeper than
3117 -- that of the attribute's prefix type.
3118
aad6babd 3119 -- if Get_Access_Level (Item'Tag)
3120 -- /= Get_Access_Level (P_Type'Tag)
3121 -- then
3122 -- raise Tag_Error;
3123 -- end if;
83aa52b6 3124
aad6babd 3125 -- String'Output (Strm, External_Tag (Item'Tag));
3126
83aa52b6 3127 -- We cannot figure out a practical way to implement this
3128 -- accessibility check on virtual machines, so we omit it.
aad6babd 3129
83aa52b6 3130 if Ada_Version >= Ada_05
662256db 3131 and then Tagged_Type_Expansion
83aa52b6 3132 then
aad6babd 3133 Insert_Action (N,
3134 Make_Implicit_If_Statement (N,
3135 Condition =>
3136 Make_Op_Ne (Loc,
3137 Left_Opnd =>
99f2248e 3138 Build_Get_Access_Level (Loc,
3139 Make_Attribute_Reference (Loc,
3140 Prefix =>
3141 Relocate_Node (
3142 Duplicate_Subexpr (Item,
3143 Name_Req => True)),
3144 Attribute_Name => Name_Tag)),
3145
aad6babd 3146 Right_Opnd =>
99f2248e 3147 Make_Integer_Literal (Loc,
3148 Type_Access_Level (P_Type))),
3149
aad6babd 3150 Then_Statements =>
3151 New_List (Make_Raise_Statement (Loc,
3152 New_Occurrence_Of (
3153 RTE (RE_Tag_Error), Loc)))));
3154 end if;
ee6ba406 3155
3156 Insert_Action (N,
3157 Make_Attribute_Reference (Loc,
3158 Prefix => New_Occurrence_Of (Standard_String, Loc),
3159 Attribute_Name => Name_Output,
3160 Expressions => New_List (
3161 Relocate_Node (Duplicate_Subexpr (Strm)),
3162 Make_Function_Call (Loc,
3163 Name =>
3164 New_Occurrence_Of (RTE (RE_External_Tag), Loc),
3165 Parameter_Associations => New_List (
3166 Make_Attribute_Reference (Loc,
3167 Prefix =>
3168 Relocate_Node
3169 (Duplicate_Subexpr (Item, Name_Req => True)),
3170 Attribute_Name => Name_Tag))))));
3171 end Tag_Write;
3172
9dfe12ae 3173 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
ee6ba406 3174
3175 -- Tagged type case, use the primitive Output function
3176
3177 elsif Is_Tagged_Type (U_Type) then
9dfe12ae 3178 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
ee6ba406 3179
99f2248e 3180 -- All other record type cases, including protected records.
3181 -- The latter only arise for expander generated code for
3182 -- handling shared passive partition access.
ee6ba406 3183
3184 else
3185 pragma Assert
3186 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3187
00f91aef 3188 -- Ada 2005 (AI-216): Program_Error is raised when executing
3189 -- the default implementation of the Output attribute of an
3190 -- unchecked union type if the type lacks default discriminant
3191 -- values.
3192
3193 if Is_Unchecked_Union (Base_Type (U_Type))
18a40e97 3194 and then No (Discriminant_Constraint (U_Type))
00f91aef 3195 then
3196 Insert_Action (N,
3197 Make_Raise_Program_Error (Loc,
3198 Reason => PE_Unchecked_Union_Restriction));
3199
3200 return;
3201 end if;
3202
ee6ba406 3203 Build_Record_Or_Elementary_Output_Procedure
3204 (Loc, Base_Type (U_Type), Decl, Pname);
3205 Insert_Action (N, Decl);
3206 end if;
3207 end if;
3208
3209 -- If we fall through, Pname is the name of the procedure to call
3210
3211 Rewrite_Stream_Proc_Call (Pname);
3212 end Output;
3213
3214 ---------
3215 -- Pos --
3216 ---------
3217
3218 -- For enumeration types with a standard representation, Pos is
d55c93e0 3219 -- handled by the back end.
ee6ba406 3220
3221 -- For enumeration types, with a non-standard representation we
3222 -- generate a call to the _Rep_To_Pos function created when the
3223 -- type was frozen. The call has the form
3224
9dfe12ae 3225 -- _rep_to_pos (expr, flag)
ee6ba406 3226
9dfe12ae 3227 -- The parameter flag is True if range checks are enabled, causing
3228 -- Program_Error to be raised if the expression has an invalid
3229 -- representation, and False if range checks are suppressed.
ee6ba406 3230
3231 -- For integer types, Pos is equivalent to a simple integer
3232 -- conversion and we rewrite it as such
3233
3234 when Attribute_Pos => Pos :
3235 declare
3236 Etyp : Entity_Id := Base_Type (Entity (Pref));
3237
3238 begin
3239 -- Deal with zero/non-zero boolean values
3240
3241 if Is_Boolean_Type (Etyp) then
3242 Adjust_Condition (First (Exprs));
3243 Etyp := Standard_Boolean;
3244 Set_Prefix (N, New_Occurrence_Of (Standard_Boolean, Loc));
3245 end if;
3246
3247 -- Case of enumeration type
3248
3249 if Is_Enumeration_Type (Etyp) then
3250
3251 -- Non-standard enumeration type (generate call)
3252
3253 if Present (Enum_Pos_To_Rep (Etyp)) then
9dfe12ae 3254 Append_To (Exprs, Rep_To_Pos_Flag (Etyp, Loc));
ee6ba406 3255 Rewrite (N,
3256 Convert_To (Typ,
3257 Make_Function_Call (Loc,
3258 Name =>
9dfe12ae 3259 New_Reference_To (TSS (Etyp, TSS_Rep_To_Pos), Loc),
ee6ba406 3260 Parameter_Associations => Exprs)));
3261
3262 Analyze_And_Resolve (N, Typ);
3263
3264 -- Standard enumeration type (do universal integer check)
3265
3266 else
3267 Apply_Universal_Integer_Attribute_Checks (N);
3268 end if;
3269
3270 -- Deal with integer types (replace by conversion)
3271
3272 elsif Is_Integer_Type (Etyp) then
3273 Rewrite (N, Convert_To (Typ, First (Exprs)));
3274 Analyze_And_Resolve (N, Typ);
3275 end if;
3276
3277 end Pos;
3278
3279 --------------
3280 -- Position --
3281 --------------
3282
d55c93e0 3283 -- We compute this if a component clause was present, otherwise we leave
3284 -- the computation up to the back end, since we don't know what layout
3285 -- will be chosen.
ee6ba406 3286
3287 when Attribute_Position => Position :
3288 declare
3289 CE : constant Entity_Id := Entity (Selector_Name (Pref));
3290
3291 begin
3292 if Present (Component_Clause (CE)) then
3293 Rewrite (N,
3294 Make_Integer_Literal (Loc,
3295 Intval => Component_Bit_Offset (CE) / System_Storage_Unit));
3296 Analyze_And_Resolve (N, Typ);
3297
3298 else
3299 Apply_Universal_Integer_Attribute_Checks (N);
3300 end if;
3301 end Position;
3302
3303 ----------
3304 -- Pred --
3305 ----------
3306
3307 -- 1. Deal with enumeration types with holes
3308 -- 2. For floating-point, generate call to attribute function
3309 -- 3. For other cases, deal with constraint checking
3310
3311 when Attribute_Pred => Pred :
3312 declare
d55c93e0 3313 Etyp : constant Entity_Id := Base_Type (Ptyp);
ee6ba406 3314
3315 begin
d55c93e0 3316
ee6ba406 3317 -- For enumeration types with non-standard representations, we
3318 -- expand typ'Pred (x) into
3319
3320 -- Pos_To_Rep (Rep_To_Pos (x) - 1)
3321
9dfe12ae 3322 -- If the representation is contiguous, we compute instead
3323 -- Lit1 + Rep_to_Pos (x -1), to catch invalid representations.
d55c93e0 3324 -- The conversion function Enum_Pos_To_Rep is defined on the
3325 -- base type, not the subtype, so we have to use the base type
3326 -- explicitly for this and other enumeration attributes.
9dfe12ae 3327
ee6ba406 3328 if Is_Enumeration_Type (Ptyp)
d55c93e0 3329 and then Present (Enum_Pos_To_Rep (Etyp))
ee6ba406 3330 then
d55c93e0 3331 if Has_Contiguous_Rep (Etyp) then
9dfe12ae 3332 Rewrite (N,
3333 Unchecked_Convert_To (Ptyp,
3334 Make_Op_Add (Loc,
3335 Left_Opnd =>
3336 Make_Integer_Literal (Loc,
3337 Enumeration_Rep (First_Literal (Ptyp))),
3338 Right_Opnd =>
3339 Make_Function_Call (Loc,
3340 Name =>
3341 New_Reference_To
d55c93e0 3342 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
9dfe12ae 3343
3344 Parameter_Associations =>
3345 New_List (
3346 Unchecked_Convert_To (Ptyp,
3347 Make_Op_Subtract (Loc,
3348 Left_Opnd =>
3349 Unchecked_Convert_To (Standard_Integer,
3350 Relocate_Node (First (Exprs))),
3351 Right_Opnd =>
3352 Make_Integer_Literal (Loc, 1))),
3353 Rep_To_Pos_Flag (Ptyp, Loc))))));
ee6ba406 3354
9dfe12ae 3355 else
3356 -- Add Boolean parameter True, to request program errror if
3357 -- we have a bad representation on our hands. If checks are
3358 -- suppressed, then add False instead
ee6ba406 3359
9dfe12ae 3360 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
3361 Rewrite (N,
3362 Make_Indexed_Component (Loc,
d55c93e0 3363 Prefix =>
3364 New_Reference_To
3365 (Enum_Pos_To_Rep (Etyp), Loc),
9dfe12ae 3366 Expressions => New_List (
3367 Make_Op_Subtract (Loc,
ee6ba406 3368 Left_Opnd =>
3369 Make_Function_Call (Loc,
3370 Name =>
d55c93e0 3371 New_Reference_To
3372 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
9dfe12ae 3373 Parameter_Associations => Exprs),
ee6ba406 3374 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
9dfe12ae 3375 end if;
ee6ba406 3376
3377 Analyze_And_Resolve (N, Typ);
3378
3379 -- For floating-point, we transform 'Pred into a call to the Pred
3380 -- floating-point attribute function in Fat_xxx (xxx is root type)
3381
3382 elsif Is_Floating_Point_Type (Ptyp) then
3383 Expand_Fpt_Attribute_R (N);
3384 Analyze_And_Resolve (N, Typ);
3385
3386 -- For modular types, nothing to do (no overflow, since wraps)
3387
3388 elsif Is_Modular_Integer_Type (Ptyp) then
3389 null;
3390
a9b57347 3391 -- For other types, if argument is marked as needing a range check or
3392 -- overflow checking is enabled, we must generate a check.
ee6ba406 3393
a9b57347 3394 elsif not Overflow_Checks_Suppressed (Ptyp)
3395 or else Do_Range_Check (First (Exprs))
3396 then
3397 Set_Do_Range_Check (First (Exprs), False);
ee6ba406 3398 Expand_Pred_Succ (N);
3399 end if;
ee6ba406 3400 end Pred;
3401
7f8eb6ed 3402 --------------
3403 -- Priority --
3404 --------------
3405
3406 -- Ada 2005 (AI-327): Dynamic ceiling priorities
3407
3408 -- We rewrite X'Priority as the following run-time call:
3409
3410 -- Get_Ceiling (X._Object)
3411
3412 -- Note that although X'Priority is notionally an object, it is quite
3413 -- deliberately not defined as an aliased object in the RM. This means
3414 -- that it works fine to rewrite it as a call, without having to worry
3415 -- about complications that would other arise from X'Priority'Access,
3416 -- which is illegal, because of the lack of aliasing.
3417
3418 when Attribute_Priority =>
3419 declare
3420 Call : Node_Id;
3421 Conctyp : Entity_Id;
3422 Object_Parm : Node_Id;
3423 Subprg : Entity_Id;
3424 RT_Subprg_Name : Node_Id;
3425
3426 begin
3427 -- Look for the enclosing concurrent type
3428
3429 Conctyp := Current_Scope;
3430 while not Is_Concurrent_Type (Conctyp) loop
3431 Conctyp := Scope (Conctyp);
3432 end loop;
3433
3434 pragma Assert (Is_Protected_Type (Conctyp));
3435
3436 -- Generate the actual of the call
3437
3438 Subprg := Current_Scope;
3439 while not Present (Protected_Body_Subprogram (Subprg)) loop
3440 Subprg := Scope (Subprg);
3441 end loop;
3442
db14252c 3443 -- Use of 'Priority inside protected entries and barriers (in
3444 -- both cases the type of the first formal of their expanded
3445 -- subprogram is Address)
3446
3447 if Etype (First_Entity (Protected_Body_Subprogram (Subprg)))
3448 = RTE (RE_Address)
3449 then
3450 declare
3451 New_Itype : Entity_Id;
3452
3453 begin
3454 -- In the expansion of protected entries the type of the
3455 -- first formal of the Protected_Body_Subprogram is an
3456 -- Address. In order to reference the _object component
3457 -- we generate:
3458
3459 -- type T is access p__ptTV;
3460 -- freeze T []
3461
3462 New_Itype := Create_Itype (E_Access_Type, N);
3463 Set_Etype (New_Itype, New_Itype);
db14252c 3464 Set_Directly_Designated_Type (New_Itype,
3465 Corresponding_Record_Type (Conctyp));
3466 Freeze_Itype (New_Itype, N);
3467
3468 -- Generate:
3469 -- T!(O)._object'unchecked_access
3470
3471 Object_Parm :=
3472 Make_Attribute_Reference (Loc,
3473 Prefix =>
3474 Make_Selected_Component (Loc,
3475 Prefix =>
3476 Unchecked_Convert_To (New_Itype,
3477 New_Reference_To
7f8eb6ed 3478 (First_Entity
db14252c 3479 (Protected_Body_Subprogram (Subprg)),
3480 Loc)),
3481 Selector_Name =>
3482 Make_Identifier (Loc, Name_uObject)),
3483 Attribute_Name => Name_Unchecked_Access);
3484 end;
3485
3486 -- Use of 'Priority inside a protected subprogram
3487
3488 else
3489 Object_Parm :=
3490 Make_Attribute_Reference (Loc,
3491 Prefix =>
3492 Make_Selected_Component (Loc,
3493 Prefix => New_Reference_To
3494 (First_Entity
3495 (Protected_Body_Subprogram (Subprg)),
3496 Loc),
3497 Selector_Name =>
3498 Make_Identifier (Loc, Name_uObject)),
3499 Attribute_Name => Name_Unchecked_Access);
3500 end if;
7f8eb6ed 3501
3502 -- Select the appropriate run-time subprogram
3503
3504 if Number_Entries (Conctyp) = 0 then
3505 RT_Subprg_Name :=
3506 New_Reference_To (RTE (RE_Get_Ceiling), Loc);
3507 else
3508 RT_Subprg_Name :=
3509 New_Reference_To (RTE (RO_PE_Get_Ceiling), Loc);
3510 end if;
3511
3512 Call :=
3513 Make_Function_Call (Loc,
3514 Name => RT_Subprg_Name,
3515 Parameter_Associations => New_List (Object_Parm));
3516
3517 Rewrite (N, Call);
db14252c 3518
3519 -- Avoid the generation of extra checks on the pointer to the
3520 -- protected object.
3521
3522 Analyze_And_Resolve (N, Typ, Suppress => Access_Check);
7f8eb6ed 3523 end;
3524
ee6ba406 3525 ------------------
3526 -- Range_Length --
3527 ------------------
3528
d55c93e0 3529 when Attribute_Range_Length => Range_Length : begin
ee6ba406 3530 -- The only special processing required is for the case where
3531 -- Range_Length is applied to an enumeration type with holes.
3532 -- In this case we transform
3533
3534 -- X'Range_Length
3535
3536 -- to
3537
3538 -- X'Pos (X'Last) - X'Pos (X'First) + 1
3539
3540 -- So that the result reflects the proper Pos values instead
3541 -- of the underlying representations.
3542
d55c93e0 3543 if Is_Enumeration_Type (Ptyp)
3544 and then Has_Non_Standard_Rep (Ptyp)
ee6ba406 3545 then
3546 Rewrite (N,
3547 Make_Op_Add (Loc,
3548 Left_Opnd =>
3549 Make_Op_Subtract (Loc,
3550 Left_Opnd =>
3551 Make_Attribute_Reference (Loc,
3552 Attribute_Name => Name_Pos,
d55c93e0 3553 Prefix => New_Occurrence_Of (Ptyp, Loc),
ee6ba406 3554 Expressions => New_List (
3555 Make_Attribute_Reference (Loc,
3556 Attribute_Name => Name_Last,
d55c93e0 3557 Prefix => New_Occurrence_Of (Ptyp, Loc)))),
ee6ba406 3558
3559 Right_Opnd =>
3560 Make_Attribute_Reference (Loc,
3561 Attribute_Name => Name_Pos,
d55c93e0 3562 Prefix => New_Occurrence_Of (Ptyp, Loc),
ee6ba406 3563 Expressions => New_List (
3564 Make_Attribute_Reference (Loc,
3565 Attribute_Name => Name_First,
d55c93e0 3566 Prefix => New_Occurrence_Of (Ptyp, Loc))))),
ee6ba406 3567
3568 Right_Opnd =>
3569 Make_Integer_Literal (Loc, 1)));
3570
3571 Analyze_And_Resolve (N, Typ);
3572
d55c93e0 3573 -- For all other cases, the attribute is handled by the back end, but
3574 -- we need to deal with the case of the range check on a universal
3575 -- integer.
ee6ba406 3576
3577 else
3578 Apply_Universal_Integer_Attribute_Checks (N);
3579 end if;
ee6ba406 3580 end Range_Length;
3581
3582 ----------
3583 -- Read --
3584 ----------
3585
3586 when Attribute_Read => Read : declare
3587 P_Type : constant Entity_Id := Entity (Pref);
3588 B_Type : constant Entity_Id := Base_Type (P_Type);
3589 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3590 Pname : Entity_Id;
3591 Decl : Node_Id;
3592 Prag : Node_Id;
3593 Arg2 : Node_Id;
3594 Rfunc : Node_Id;
3595 Lhs : Node_Id;
3596 Rhs : Node_Id;
3597
3598 begin
3599 -- If no underlying type, we have an error that will be diagnosed
3600 -- elsewhere, so here we just completely ignore the expansion.
3601
3602 if No (U_Type) then
3603 return;
3604 end if;
3605
3606 -- The simple case, if there is a TSS for Read, just call it
3607
9dfe12ae 3608 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Read);
ee6ba406 3609
3610 if Present (Pname) then
3611 null;
3612
3613 else
3614 -- If there is a Stream_Convert pragma, use it, we rewrite
3615
3616 -- sourcetyp'Read (stream, Item)
3617
3618 -- as
3619
3620 -- Item := sourcetyp (strmread (strmtyp'Input (Stream)));
3621
aad6babd 3622 -- where strmread is the given Read function that converts an
3623 -- argument of type strmtyp to type sourcetyp or a type from which
3624 -- it is derived. The conversion to sourcetyp is required in the
3625 -- latter case.
ee6ba406 3626
3627 -- A special case arises if Item is a type conversion in which
3628 -- case, we have to expand to:
3629
3630 -- Itemx := typex (strmread (strmtyp'Input (Stream)));
3631
3632 -- where Itemx is the expression of the type conversion (i.e.
3633 -- the actual object), and typex is the type of Itemx.
3634
5245b786 3635 Prag := Get_Stream_Convert_Pragma (P_Type);
ee6ba406 3636
3637 if Present (Prag) then
3638 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
3639 Rfunc := Entity (Expression (Arg2));
3640 Lhs := Relocate_Node (Next (First (Exprs)));
3641 Rhs :=
83aa52b6 3642 OK_Convert_To (B_Type,
ee6ba406 3643 Make_Function_Call (Loc,
3644 Name => New_Occurrence_Of (Rfunc, Loc),
3645 Parameter_Associations => New_List (
3646 Make_Attribute_Reference (Loc,
3647 Prefix =>
3648 New_Occurrence_Of
3649 (Etype (First_Formal (Rfunc)), Loc),
3650 Attribute_Name => Name_Input,
3651 Expressions => New_List (
3652 Relocate_Node (First (Exprs)))))));
3653
3654 if Nkind (Lhs) = N_Type_Conversion then
3655 Lhs := Expression (Lhs);
3656 Rhs := Convert_To (Etype (Lhs), Rhs);
3657 end if;
3658
3659 Rewrite (N,
3660 Make_Assignment_Statement (Loc,
9dfe12ae 3661 Name => Lhs,
ee6ba406 3662 Expression => Rhs));
3663 Set_Assignment_OK (Lhs);
3664 Analyze (N);
3665 return;
3666
3667 -- For elementary types, we call the I_xxx routine using the first
3668 -- parameter and then assign the result into the second parameter.
3669 -- We set Assignment_OK to deal with the conversion case.
3670
3671 elsif Is_Elementary_Type (U_Type) then
3672 declare
3673 Lhs : Node_Id;
3674 Rhs : Node_Id;
3675
3676 begin
3677 Lhs := Relocate_Node (Next (First (Exprs)));
3678 Rhs := Build_Elementary_Input_Call (N);
3679
3680 if Nkind (Lhs) = N_Type_Conversion then
3681 Lhs := Expression (Lhs);
3682 Rhs := Convert_To (Etype (Lhs), Rhs);
3683 end if;
3684
3685 Set_Assignment_OK (Lhs);
3686
3687 Rewrite (N,
3688 Make_Assignment_Statement (Loc,
3689 Name => Lhs,
3690 Expression => Rhs));
3691
3692 Analyze (N);
3693 return;
3694 end;
3695
3696 -- Array type case
3697
3698 elsif Is_Array_Type (U_Type) then
3699 Build_Array_Read_Procedure (N, U_Type, Decl, Pname);
3700 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3701
3702 -- Tagged type case, use the primitive Read function. Note that
3703 -- this will dispatch in the class-wide case which is what we want
3704
3705 elsif Is_Tagged_Type (U_Type) then
9dfe12ae 3706 Pname := Find_Prim_Op (U_Type, TSS_Stream_Read);
ee6ba406 3707
aad6babd 3708 -- All other record type cases, including protected records. The
3709 -- latter only arise for expander generated code for handling
3710 -- shared passive partition access.
ee6ba406 3711
3712 else
3713 pragma Assert
3714 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3715
00f91aef 3716 -- Ada 2005 (AI-216): Program_Error is raised when executing
3717 -- the default implementation of the Read attribute of an
3718 -- Unchecked_Union type.
3719
3720 if Is_Unchecked_Union (Base_Type (U_Type)) then
3721 Insert_Action (N,
3722 Make_Raise_Program_Error (Loc,
3723 Reason => PE_Unchecked_Union_Restriction));
3724 end if;
3725
ee6ba406 3726 if Has_Discriminants (U_Type)
3727 and then Present
3728 (Discriminant_Default_Value (First_Discriminant (U_Type)))
3729 then
3730 Build_Mutable_Record_Read_Procedure
3731 (Loc, Base_Type (U_Type), Decl, Pname);
ee6ba406 3732 else
3733 Build_Record_Read_Procedure
3734 (Loc, Base_Type (U_Type), Decl, Pname);
3735 end if;
3736
3737 -- Suppress checks, uninitialized or otherwise invalid
3738 -- data does not cause constraint errors to be raised for
3739 -- a complete record read.
3740
3741 Insert_Action (N, Decl, All_Checks);
3742 end if;
3743 end if;
3744
3745 Rewrite_Stream_Proc_Call (Pname);
3746 end Read;
3747
3748 ---------------
3749 -- Remainder --
3750 ---------------
3751
3752 -- Transforms 'Remainder into a call to the floating-point attribute
3753 -- function Remainder in Fat_xxx (where xxx is the root type)
3754
3755 when Attribute_Remainder =>
3756 Expand_Fpt_Attribute_RR (N);
3757
d55c93e0 3758 ------------
3759 -- Result --
3760 ------------
3761
3762 -- Transform 'Result into reference to _Result formal. At the point
3763 -- where a legal 'Result attribute is expanded, we know that we are in
3764 -- the context of a _Postcondition function with a _Result parameter.
3765
3766 when Attribute_Result =>
3767 Rewrite (N,
3768 Make_Identifier (Loc,
3769 Chars => Name_uResult));
3770 Analyze_And_Resolve (N, Typ);
3771
ee6ba406 3772 -----------
3773 -- Round --
3774 -----------
3775
aad6babd 3776 -- The handling of the Round attribute is quite delicate. The processing
3777 -- in Sem_Attr introduced a conversion to universal real, reflecting the
3778 -- semantics of Round, but we do not want anything to do with universal
3779 -- real at runtime, since this corresponds to using floating-point
3780 -- arithmetic.
3781
3782 -- What we have now is that the Etype of the Round attribute correctly
3783 -- indicates the final result type. The operand of the Round is the
3784 -- conversion to universal real, described above, and the operand of
3785 -- this conversion is the actual operand of Round, which may be the
3786 -- special case of a fixed point multiplication or division (Etype =
3787 -- universal fixed)
3788
3789 -- The exapander will expand first the operand of the conversion, then
3790 -- the conversion, and finally the round attribute itself, since we
3791 -- always work inside out. But we cannot simply process naively in this
3792 -- order. In the semantic world where universal fixed and real really
3793 -- exist and have infinite precision, there is no problem, but in the
3794 -- implementation world, where universal real is a floating-point type,
3795 -- we would get the wrong result.
3796
3797 -- So the approach is as follows. First, when expanding a multiply or
3798 -- divide whose type is universal fixed, we do nothing at all, instead
3799 -- deferring the operation till later.
ee6ba406 3800
3801 -- The actual processing is done in Expand_N_Type_Conversion which
aad6babd 3802 -- handles the special case of Round by looking at its parent to see if
3803 -- it is a Round attribute, and if it is, handling the conversion (or
3804 -- its fixed multiply/divide child) in an appropriate manner.
ee6ba406 3805
3806 -- This means that by the time we get to expanding the Round attribute
3807 -- itself, the Round is nothing more than a type conversion (and will
3808 -- often be a null type conversion), so we just replace it with the
3809 -- appropriate conversion operation.
3810
3811 when Attribute_Round =>
3812 Rewrite (N,
3813 Convert_To (Etype (N), Relocate_Node (First (Exprs))));
3814 Analyze_And_Resolve (N);
3815
3816 --------------
3817 -- Rounding --
3818 --------------
3819
3820 -- Transforms 'Rounding into a call to the floating-point attribute
3821 -- function Rounding in Fat_xxx (where xxx is the root type)
3822
3823 when Attribute_Rounding =>
3824 Expand_Fpt_Attribute_R (N);
3825
3826 -------------
3827 -- Scaling --
3828 -------------
3829
3830 -- Transforms 'Scaling into a call to the floating-point attribute
3831 -- function Scaling in Fat_xxx (where xxx is the root type)
3832
3833 when Attribute_Scaling =>
3834 Expand_Fpt_Attribute_RI (N);
3835
3836 ----------
3837 -- Size --
3838 ----------
3839
3840 when Attribute_Size |
3841 Attribute_Object_Size |
3842 Attribute_Value_Size |
3843 Attribute_VADS_Size => Size :
3844
3845 declare
ee6ba406 3846 Siz : Uint;
9dfe12ae 3847 New_Node : Node_Id;
ee6ba406 3848
3849 begin
3850 -- Processing for VADS_Size case. Note that this processing removes
3851 -- all traces of VADS_Size from the tree, and completes all required
3852 -- processing for VADS_Size by translating the attribute reference
3853 -- to an appropriate Size or Object_Size reference.
3854
3855 if Id = Attribute_VADS_Size
3856 or else (Use_VADS_Size and then Id = Attribute_Size)
3857 then
3858 -- If the size is specified, then we simply use the specified
3859 -- size. This applies to both types and objects. The size of an
3860 -- object can be specified in the following ways:
3861
3862 -- An explicit size object is given for an object
3863 -- A component size is specified for an indexed component
3864 -- A component clause is specified for a selected component
3865 -- The object is a component of a packed composite object
3866
3867 -- If the size is specified, then VADS_Size of an object
3868
3869 if (Is_Entity_Name (Pref)
3870 and then Present (Size_Clause (Entity (Pref))))
3871 or else
3872 (Nkind (Pref) = N_Component_Clause
3873 and then (Present (Component_Clause
3874 (Entity (Selector_Name (Pref))))
3875 or else Is_Packed (Etype (Prefix (Pref)))))
3876 or else
3877 (Nkind (Pref) = N_Indexed_Component
3878 and then (Component_Size (Etype (Prefix (Pref))) /= 0
3879 or else Is_Packed (Etype (Prefix (Pref)))))
3880 then
3881 Set_Attribute_Name (N, Name_Size);
3882
3883 -- Otherwise if we have an object rather than a type, then the
3884 -- VADS_Size attribute applies to the type of the object, rather
3885 -- than the object itself. This is one of the respects in which
3886 -- VADS_Size differs from Size.
3887
3888 else
3889 if (not Is_Entity_Name (Pref)
3890 or else not Is_Type (Entity (Pref)))
d55c93e0 3891 and then (Is_Scalar_Type (Ptyp) or else Is_Constrained (Ptyp))
ee6ba406 3892 then
d55c93e0 3893 Rewrite (Pref, New_Occurrence_Of (Ptyp, Loc));
ee6ba406 3894 end if;
3895
aad6babd 3896 -- For a scalar type for which no size was explicitly given,
3897 -- VADS_Size means Object_Size. This is the other respect in
3898 -- which VADS_Size differs from Size.
ee6ba406 3899
d55c93e0 3900 if Is_Scalar_Type (Ptyp) and then No (Size_Clause (Ptyp)) then
ee6ba406 3901 Set_Attribute_Name (N, Name_Object_Size);
3902
3903 -- In all other cases, Size and VADS_Size are the sane
3904
3905 else
3906 Set_Attribute_Name (N, Name_Size);
3907 end if;
3908 end if;
3909 end if;
3910
d55c93e0 3911 -- For class-wide types, X'Class'Size is transformed into a direct
3912 -- reference to the Size of the class type, so that the back end does
3913 -- not have to deal with the X'Class'Size reference.
ee6ba406 3914
9dfe12ae 3915 if Is_Entity_Name (Pref)
3916 and then Is_Class_Wide_Type (Entity (Pref))
3917 then
3918 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
3919 return;
3920
1550b445 3921 -- For X'Size applied to an object of a class-wide type, transform
9dfe12ae 3922 -- X'Size into a call to the primitive operation _Size applied to X.
3923
442049cc 3924 elsif Is_Class_Wide_Type (Ptyp)
3925 or else (Id = Attribute_Size
3926 and then Is_Tagged_Type (Ptyp)
3927 and then Has_Unknown_Discriminants (Ptyp))
3928 then
99f2248e 3929 -- No need to do anything else compiling under restriction
3930 -- No_Dispatching_Calls. During the semantic analysis we
3931 -- already notified such violation.
3932
3933 if Restriction_Active (No_Dispatching_Calls) then
3934 return;
3935 end if;
3936
ee6ba406 3937 New_Node :=
3938 Make_Function_Call (Loc,
3939 Name => New_Reference_To
3940 (Find_Prim_Op (Ptyp, Name_uSize), Loc),
3941 Parameter_Associations => New_List (Pref));
3942
3943 if Typ /= Standard_Long_Long_Integer then
3944
3945 -- The context is a specific integer type with which the
3946 -- original attribute was compatible. The function has a
3947 -- specific type as well, so to preserve the compatibility
3948 -- we must convert explicitly.
3949
3950 New_Node := Convert_To (Typ, New_Node);
3951 end if;
3952
3953 Rewrite (N, New_Node);
3954 Analyze_And_Resolve (N, Typ);
442049cc 3955 return;
83aa52b6 3956
3957 -- Case of known RM_Size of a type
3958
3959 elsif (Id = Attribute_Size or else Id = Attribute_Value_Size)
3960 and then Is_Entity_Name (Pref)
3961 and then Is_Type (Entity (Pref))
3962 and then Known_Static_RM_Size (Entity (Pref))
3963 then
3964 Siz := RM_Size (Entity (Pref));
3965
3966 -- Case of known Esize of a type
3967
3968 elsif Id = Attribute_Object_Size
3969 and then Is_Entity_Name (Pref)
3970 and then Is_Type (Entity (Pref))
3971 and then Known_Static_Esize (Entity (Pref))
3972 then
3973 Siz := Esize (Entity (Pref));
3974
3975 -- Case of known size of object
3976
3977 elsif Id = Attribute_Size
3978 and then Is_Entity_Name (Pref)
3979 and then Is_Object (Entity (Pref))
3980 and then Known_Esize (Entity (Pref))
3981 and then Known_Static_Esize (Entity (Pref))
3982 then
3983 Siz := Esize (Entity (Pref));
ee6ba406 3984
3985 -- For an array component, we can do Size in the front end
3986 -- if the component_size of the array is set.
3987
3988 elsif Nkind (Pref) = N_Indexed_Component then
3989 Siz := Component_Size (Etype (Prefix (Pref)));
3990
aad6babd 3991 -- For a record component, we can do Size in the front end if there
3992 -- is a component clause, or if the record is packed and the
3993 -- component's size is known at compile time.
ee6ba406 3994
3995 elsif Nkind (Pref) = N_Selected_Component then
3996 declare
3997 Rec : constant Entity_Id := Etype (Prefix (Pref));
3998 Comp : constant Entity_Id := Entity (Selector_Name (Pref));
3999
4000 begin
4001 if Present (Component_Clause (Comp)) then
4002 Siz := Esize (Comp);
4003
4004 elsif Is_Packed (Rec) then
4005 Siz := RM_Size (Ptyp);
4006
4007 else
4008 Apply_Universal_Integer_Attribute_Checks (N);
4009 return;
4010 end if;
4011 end;
4012
d55c93e0 4013 -- All other cases are handled by the back end
ee6ba406 4014
4015 else
4016 Apply_Universal_Integer_Attribute_Checks (N);
4017
1550b445 4018 -- If Size is applied to a formal parameter that is of a packed
4019 -- array subtype, then apply Size to the actual subtype.
ee6ba406 4020
4021 if Is_Entity_Name (Pref)
4022 and then Is_Formal (Entity (Pref))
d55c93e0 4023 and then Is_Array_Type (Ptyp)
4024 and then Is_Packed (Ptyp)
ee6ba406 4025 then
4026 Rewrite (N,
4027 Make_Attribute_Reference (Loc,
4028 Prefix =>
4029 New_Occurrence_Of (Get_Actual_Subtype (Pref), Loc),
4030 Attribute_Name => Name_Size));
4031 Analyze_And_Resolve (N, Typ);
4032 end if;
4033
83aa52b6 4034 -- If Size applies to a dereference of an access to unconstrained
d55c93e0 4035 -- packed array, the back end needs to see its unconstrained
4036 -- nominal type, but also a hint to the actual constrained type.
1550b445 4037
4038 if Nkind (Pref) = N_Explicit_Dereference
d55c93e0 4039 and then Is_Array_Type (Ptyp)
4040 and then not Is_Constrained (Ptyp)
4041 and then Is_Packed (Ptyp)
1550b445 4042 then
4043 Set_Actual_Designated_Subtype (Pref,
4044 Get_Actual_Subtype (Pref));
4045 end if;
4046
ee6ba406 4047 return;
4048 end if;
4049
4050 -- Common processing for record and array component case
4051
83aa52b6 4052 if Siz /= No_Uint and then Siz /= 0 then
6deeca1d 4053 declare
4054 CS : constant Boolean := Comes_From_Source (N);
ee6ba406 4055
6deeca1d 4056 begin
4057 Rewrite (N, Make_Integer_Literal (Loc, Siz));
4058
4059 -- This integer literal is not a static expression. We do not
4060 -- call Analyze_And_Resolve here, because this would activate
4061 -- the circuit for deciding that a static value was out of
4062 -- range, and we don't want that.
ee6ba406 4063
6deeca1d 4064 -- So just manually set the type, mark the expression as non-
4065 -- static, and then ensure that the result is checked properly
4066 -- if the attribute comes from source (if it was internally
4067 -- generated, we never need a constraint check).
ee6ba406 4068
6deeca1d 4069 Set_Etype (N, Typ);
4070 Set_Is_Static_Expression (N, False);
4071
4072 if CS then
4073 Apply_Constraint_Check (N, Typ);
4074 end if;
4075 end;
ee6ba406 4076 end if;
4077 end Size;
4078
4079 ------------------
4080 -- Storage_Pool --
4081 ------------------
4082
4083 when Attribute_Storage_Pool =>
4084 Rewrite (N,
4085 Make_Type_Conversion (Loc,
4086 Subtype_Mark => New_Reference_To (Etype (N), Loc),
4087 Expression => New_Reference_To (Entity (N), Loc)));
4088 Analyze_And_Resolve (N, Typ);
4089
4090 ------------------
4091 -- Storage_Size --
4092 ------------------
4093
d55c93e0 4094 when Attribute_Storage_Size => Storage_Size : begin
ee6ba406 4095
ee6ba406 4096 -- Access type case, always go to the root type
4097
4098 -- The case of access types results in a value of zero for the case
4099 -- where no storage size attribute clause has been given. If a
4100 -- storage size has been given, then the attribute is converted
4101 -- to a reference to the variable used to hold this value.
4102
4103 if Is_Access_Type (Ptyp) then
4104 if Present (Storage_Size_Variable (Root_Type (Ptyp))) then
4105 Rewrite (N,
4106 Make_Attribute_Reference (Loc,
4107 Prefix => New_Reference_To (Typ, Loc),
4108 Attribute_Name => Name_Max,
4109 Expressions => New_List (
4110 Make_Integer_Literal (Loc, 0),
4111 Convert_To (Typ,
4112 New_Reference_To
4113 (Storage_Size_Variable (Root_Type (Ptyp)), Loc)))));
4114
4115 elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then
4116 Rewrite (N,
4117 OK_Convert_To (Typ,
4118 Make_Function_Call (Loc,
9dfe12ae 4119 Name =>
4120 New_Reference_To
7f8eb6ed 4121 (Find_Prim_Op
4122 (Etype (Associated_Storage_Pool (Root_Type (Ptyp))),
4123 Attribute_Name (N)),
4124 Loc),
4125
4126 Parameter_Associations => New_List (
4127 New_Reference_To
4128 (Associated_Storage_Pool (Root_Type (Ptyp)), Loc)))));
ee6ba406 4129
ee6ba406 4130 else
4131 Rewrite (N, Make_Integer_Literal (Loc, 0));
4132 end if;
4133
4134 Analyze_And_Resolve (N, Typ);
4135
7f8eb6ed 4136 -- For tasks, we retrieve the size directly from the TCB. The
4137 -- size may depend on a discriminant of the type, and therefore
4138 -- can be a per-object expression, so type-level information is
4139 -- not sufficient in general. There are four cases to consider:
ee6ba406 4140
7f8eb6ed 4141 -- a) If the attribute appears within a task body, the designated
4142 -- TCB is obtained by a call to Self.
ee6ba406 4143
7f8eb6ed 4144 -- b) If the prefix of the attribute is the name of a task object,
4145 -- the designated TCB is the one stored in the corresponding record.
ee6ba406 4146
7f8eb6ed 4147 -- c) If the prefix is a task type, the size is obtained from the
4148 -- size variable created for each task type
ee6ba406 4149
7f8eb6ed 4150 -- d) If no storage_size was specified for the type , there is no
4151 -- size variable, and the value is a system-specific default.
ee6ba406 4152
4153 else
7f8eb6ed 4154 if In_Open_Scopes (Ptyp) then
4155
4156 -- Storage_Size (Self)
4157
ee6ba406 4158 Rewrite (N,
4159 Convert_To (Typ,
4160 Make_Function_Call (Loc,
4161 Name =>
7f8eb6ed 4162 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4163 Parameter_Associations =>
4164 New_List (
4165 Make_Function_Call (Loc,
4166 Name =>
4167 New_Reference_To (RTE (RE_Self), Loc))))));
ee6ba406 4168
7f8eb6ed 4169 elsif not Is_Entity_Name (Pref)
4170 or else not Is_Type (Entity (Pref))
4171 then
4172 -- Storage_Size (Rec (Obj).Size)
4173
4174 Rewrite (N,
4175 Convert_To (Typ,
4176 Make_Function_Call (Loc,
4177 Name =>
4178 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4179 Parameter_Associations =>
ee6ba406 4180 New_List (
4181 Make_Selected_Component (Loc,
4182 Prefix =>
4183 Unchecked_Convert_To (
4184 Corresponding_Record_Type (Ptyp),
7f8eb6ed 4185 New_Copy_Tree (Pref)),
ee6ba406 4186 Selector_Name =>
7f8eb6ed 4187 Make_Identifier (Loc, Name_uTask_Id))))));
ee6ba406 4188
7f8eb6ed 4189 elsif Present (Storage_Size_Variable (Ptyp)) then
ee6ba406 4190
7f8eb6ed 4191 -- Static storage size pragma given for type: retrieve value
4192 -- from its allocated storage variable.
ee6ba406 4193
7f8eb6ed 4194 Rewrite (N,
4195 Convert_To (Typ,
4196 Make_Function_Call (Loc,
4197 Name => New_Occurrence_Of (
4198 RTE (RE_Adjust_Storage_Size), Loc),
4199 Parameter_Associations =>
4200 New_List (
4201 New_Reference_To (
4202 Storage_Size_Variable (Ptyp), Loc)))));
4203 else
4204 -- Get system default
4205
4206 Rewrite (N,
4207 Convert_To (Typ,
4208 Make_Function_Call (Loc,
4209 Name =>
4210 New_Occurrence_Of (
4211 RTE (RE_Default_Stack_Size), Loc))));
ee6ba406 4212 end if;
7f8eb6ed 4213
4214 Analyze_And_Resolve (N, Typ);
ee6ba406 4215 end if;
4216 end Storage_Size;
4217
7189d17f 4218 -----------------
4219 -- Stream_Size --
4220 -----------------
4221
4222 when Attribute_Stream_Size => Stream_Size : declare
7189d17f 4223 Size : Int;
4224
4225 begin
4226 -- If we have a Stream_Size clause for this type use it, otherwise
4227 -- the Stream_Size if the size of the type.
4228
4229 if Has_Stream_Size_Clause (Ptyp) then
7f8eb6ed 4230 Size :=
4231 UI_To_Int
4232 (Static_Integer (Expression (Stream_Size_Clause (Ptyp))));
7189d17f 4233 else
4234 Size := UI_To_Int (Esize (Ptyp));
4235 end if;
4236
4237 Rewrite (N, Make_Integer_Literal (Loc, Intval => Size));
4238 Analyze_And_Resolve (N, Typ);
4239 end Stream_Size;
4240
ee6ba406 4241 ----------
4242 -- Succ --
4243 ----------
4244
4245 -- 1. Deal with enumeration types with holes
4246 -- 2. For floating-point, generate call to attribute function
4247 -- 3. For other cases, deal with constraint checking
4248
4249 when Attribute_Succ => Succ :
4250 declare
d55c93e0 4251 Etyp : constant Entity_Id := Base_Type (Ptyp);
ee6ba406 4252
4253 begin
d55c93e0 4254
ee6ba406 4255 -- For enumeration types with non-standard representations, we
4256 -- expand typ'Succ (x) into
4257
4258 -- Pos_To_Rep (Rep_To_Pos (x) + 1)
4259
9dfe12ae 4260 -- If the representation is contiguous, we compute instead
4261 -- Lit1 + Rep_to_Pos (x+1), to catch invalid representations.
4262
ee6ba406 4263 if Is_Enumeration_Type (Ptyp)
d55c93e0 4264 and then Present (Enum_Pos_To_Rep (Etyp))
ee6ba406 4265 then
d55c93e0 4266 if Has_Contiguous_Rep (Etyp) then
9dfe12ae 4267 Rewrite (N,
4268 Unchecked_Convert_To (Ptyp,
4269 Make_Op_Add (Loc,
4270 Left_Opnd =>
4271 Make_Integer_Literal (Loc,
4272 Enumeration_Rep (First_Literal (Ptyp))),
4273 Right_Opnd =>
4274 Make_Function_Call (Loc,
4275 Name =>
4276 New_Reference_To
d55c93e0 4277 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
9dfe12ae 4278
4279 Parameter_Associations =>
4280 New_List (
4281 Unchecked_Convert_To (Ptyp,
4282 Make_Op_Add (Loc,
4283 Left_Opnd =>
4284 Unchecked_Convert_To (Standard_Integer,
4285 Relocate_Node (First (Exprs))),
4286 Right_Opnd =>
4287 Make_Integer_Literal (Loc, 1))),
4288 Rep_To_Pos_Flag (Ptyp, Loc))))));
4289 else
4290 -- Add Boolean parameter True, to request program errror if
4291 -- we have a bad representation on our hands. Add False if
4292 -- checks are suppressed.
ee6ba406 4293
9dfe12ae 4294 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
4295 Rewrite (N,
4296 Make_Indexed_Component (Loc,
d55c93e0 4297 Prefix =>
4298 New_Reference_To
4299 (Enum_Pos_To_Rep (Etyp), Loc),
9dfe12ae 4300 Expressions => New_List (
4301 Make_Op_Add (Loc,
4302 Left_Opnd =>
4303 Make_Function_Call (Loc,
4304 Name =>
4305 New_Reference_To
d55c93e0 4306 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
9dfe12ae 4307 Parameter_Associations => Exprs),
4308 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
4309 end if;
ee6ba406 4310
4311 Analyze_And_Resolve (N, Typ);
4312
4313 -- For floating-point, we transform 'Succ into a call to the Succ
4314 -- floating-point attribute function in Fat_xxx (xxx is root type)
4315
4316 elsif Is_Floating_Point_Type (Ptyp) then
4317 Expand_Fpt_Attribute_R (N);
4318 Analyze_And_Resolve (N, Typ);
4319
4320 -- For modular types, nothing to do (no overflow, since wraps)
4321
4322 elsif Is_Modular_Integer_Type (Ptyp) then
4323 null;
4324
a9b57347 4325 -- For other types, if argument is marked as needing a range check or
4326 -- overflow checking is enabled, we must generate a check.
ee6ba406 4327
a9b57347 4328 elsif not Overflow_Checks_Suppressed (Ptyp)
4329 or else Do_Range_Check (First (Exprs))
4330 then
4331 Set_Do_Range_Check (First (Exprs), False);
ee6ba406 4332 Expand_Pred_Succ (N);
4333 end if;
4334 end Succ;
4335
4336 ---------
4337 -- Tag --
4338 ---------
4339
4340 -- Transforms X'Tag into a direct reference to the tag of X
4341
4342 when Attribute_Tag => Tag :
4343 declare
4344 Ttyp : Entity_Id;
4345 Prefix_Is_Type : Boolean;
4346
4347 begin
4348 if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then
4349 Ttyp := Entity (Pref);
4350 Prefix_Is_Type := True;
4351 else
d55c93e0 4352 Ttyp := Ptyp;
ee6ba406 4353 Prefix_Is_Type := False;
4354 end if;
4355
4356 if Is_Class_Wide_Type (Ttyp) then
4357 Ttyp := Root_Type (Ttyp);
4358 end if;
4359
4360 Ttyp := Underlying_Type (Ttyp);
4361
8188864b 4362 -- Ada 2005: The type may be a synchronized tagged type, in which
4363 -- case the tag information is stored in the corresponding record.
4364
4365 if Is_Concurrent_Type (Ttyp) then
4366 Ttyp := Corresponding_Record_Type (Ttyp);
4367 end if;
4368
ee6ba406 4369 if Prefix_Is_Type then
1d7e0b5b 4370
83aa52b6 4371 -- For VMs we leave the type attribute unexpanded because
1d7e0b5b 4372 -- there's not a dispatching table to reference.
4373
662256db 4374 if Tagged_Type_Expansion then
1d7e0b5b 4375 Rewrite (N,
4376 Unchecked_Convert_To (RTE (RE_Tag),
4660e715 4377 New_Reference_To
4378 (Node (First_Elmt (Access_Disp_Table (Ttyp))), Loc)));
1d7e0b5b 4379 Analyze_And_Resolve (N, RTE (RE_Tag));
4380 end if;
ee6ba406 4381
b6dbc975 4382 -- Ada 2005 (AI-251): The use of 'Tag in the sources always
83aa52b6 4383 -- references the primary tag of the actual object. If 'Tag is
4384 -- applied to class-wide interface objects we generate code that
4385 -- displaces "this" to reference the base of the object.
4386
4387 elsif Comes_From_Source (N)
4388 and then Is_Class_Wide_Type (Etype (Prefix (N)))
4389 and then Is_Interface (Etype (Prefix (N)))
4390 then
4391 -- Generate:
4392 -- (To_Tag_Ptr (Prefix'Address)).all
4393
4394 -- Note that Prefix'Address is recursively expanded into a call
4395 -- to Base_Address (Obj.Tag)
4396
f0bf2ff3 4397 -- Not needed for VM targets, since all handled by the VM
4398
662256db 4399 if Tagged_Type_Expansion then
f0bf2ff3 4400 Rewrite (N,
4401 Make_Explicit_Dereference (Loc,
4402 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
4403 Make_Attribute_Reference (Loc,
4404 Prefix => Relocate_Node (Pref),
4405 Attribute_Name => Name_Address))));
4406 Analyze_And_Resolve (N, RTE (RE_Tag));
4407 end if;
83aa52b6 4408
ee6ba406 4409 else
4410 Rewrite (N,
4411 Make_Selected_Component (Loc,
4412 Prefix => Relocate_Node (Pref),
4413 Selector_Name =>
4660e715 4414 New_Reference_To (First_Tag_Component (Ttyp), Loc)));
1d7e0b5b 4415 Analyze_And_Resolve (N, RTE (RE_Tag));
ee6ba406 4416 end if;
ee6ba406 4417 end Tag;
4418
4419 ----------------
4420 -- Terminated --
4421 ----------------
4422
aad6babd 4423 -- Transforms 'Terminated attribute into a call to Terminated function
ee6ba406 4424
4425 when Attribute_Terminated => Terminated :
4426 begin
1550b445 4427 -- The prefix of Terminated is of a task interface class-wide type.
4428 -- Generate:
83aa52b6 4429 -- terminated (Task_Id (Pref._disp_get_task_id));
1550b445 4430
4431 if Ada_Version >= Ada_05
d55c93e0 4432 and then Ekind (Ptyp) = E_Class_Wide_Type
4433 and then Is_Interface (Ptyp)
4434 and then Is_Task_Interface (Ptyp)
1550b445 4435 then
4436 Rewrite (N,
4437 Make_Function_Call (Loc,
4438 Name =>
4439 New_Reference_To (RTE (RE_Terminated), Loc),
4440 Parameter_Associations => New_List (
83aa52b6 4441 Make_Unchecked_Type_Conversion (Loc,
4442 Subtype_Mark =>
4443 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
4444 Expression =>
4445 Make_Selected_Component (Loc,
4446 Prefix =>
4447 New_Copy_Tree (Pref),
4448 Selector_Name =>
4449 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
1550b445 4450
4451 elsif Restricted_Profile then
ee6ba406 4452 Rewrite (N,
4453 Build_Call_With_Task (Pref, RTE (RE_Restricted_Terminated)));
4454
4455 else
4456 Rewrite (N,
4457 Build_Call_With_Task (Pref, RTE (RE_Terminated)));
4458 end if;
4459
4460 Analyze_And_Resolve (N, Standard_Boolean);
4461 end Terminated;
4462
4463 ----------------
4464 -- To_Address --
4465 ----------------
4466
4467 -- Transforms System'To_Address (X) into unchecked conversion
4468 -- from (integral) type of X to type address.
4469
4470 when Attribute_To_Address =>
4471 Rewrite (N,
4472 Unchecked_Convert_To (RTE (RE_Address),
4473 Relocate_Node (First (Exprs))));
4474 Analyze_And_Resolve (N, RTE (RE_Address));
4475
5690e662 4476 ------------
4477 -- To_Any --
4478 ------------
4479
4480 when Attribute_To_Any => To_Any : declare
4481 P_Type : constant Entity_Id := Etype (Pref);
4482 Decls : constant List_Id := New_List;
4483 begin
4484 Rewrite (N,
4485 Build_To_Any_Call
4486 (Convert_To (P_Type,
4487 Relocate_Node (First (Exprs))), Decls));
4488 Insert_Actions (N, Decls);
4489 Analyze_And_Resolve (N, RTE (RE_Any));
4490 end To_Any;
4491
ee6ba406 4492 ----------------
4493 -- Truncation --
4494 ----------------
4495
4496 -- Transforms 'Truncation into a call to the floating-point attribute
99f2248e 4497 -- function Truncation in Fat_xxx (where xxx is the root type).
4498 -- Expansion is avoided for cases the back end can handle directly.
ee6ba406 4499
4500 when Attribute_Truncation =>
99f2248e 4501 if not Is_Inline_Floating_Point_Attribute (N) then
4502 Expand_Fpt_Attribute_R (N);
4503 end if;
ee6ba406 4504
5690e662 4505 --------------
4506 -- TypeCode --
4507 --------------
4508
4509 when Attribute_TypeCode => TypeCode : declare
4510 P_Type : constant Entity_Id := Etype (Pref);
4511 Decls : constant List_Id := New_List;
4512 begin
4513 Rewrite (N, Build_TypeCode_Call (Loc, P_Type, Decls));
4514 Insert_Actions (N, Decls);
4515 Analyze_And_Resolve (N, RTE (RE_TypeCode));
4516 end TypeCode;
4517
ee6ba406 4518 -----------------------
4519 -- Unbiased_Rounding --
4520 -----------------------
4521
4522 -- Transforms 'Unbiased_Rounding into a call to the floating-point
4523 -- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the
99f2248e 4524 -- root type). Expansion is avoided for cases the back end can handle
4525 -- directly.
ee6ba406 4526
4527 when Attribute_Unbiased_Rounding =>
99f2248e 4528 if not Is_Inline_Floating_Point_Attribute (N) then
4529 Expand_Fpt_Attribute_R (N);
4530 end if;
ee6ba406 4531
ee6ba406 4532 -----------------
4533 -- UET_Address --
4534 -----------------
4535
4536 when Attribute_UET_Address => UET_Address : declare
4537 Ent : constant Entity_Id :=
4538 Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
4539
4540 begin
4541 Insert_Action (N,
4542 Make_Object_Declaration (Loc,
4543 Defining_Identifier => Ent,
4544 Aliased_Present => True,
4545 Object_Definition =>
4546 New_Occurrence_Of (RTE (RE_Address), Loc)));
4547
4548 -- Construct name __gnat_xxx__SDP, where xxx is the unit name
4549 -- in normal external form.
4550
4551 Get_External_Unit_Name_String (Get_Unit_Name (Pref));
4552 Name_Buffer (1 + 7 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
4553 Name_Len := Name_Len + 7;
4554 Name_Buffer (1 .. 7) := "__gnat_";
4555 Name_Buffer (Name_Len + 1 .. Name_Len + 5) := "__SDP";
4556 Name_Len := Name_Len + 5;
4557
4558 Set_Is_Imported (Ent);
4559 Set_Interface_Name (Ent,
4560 Make_String_Literal (Loc,
4561 Strval => String_From_Name_Buffer));
4562
f947f061 4563 -- Set entity as internal to ensure proper Sprint output of its
4564 -- implicit importation.
4565
4566 Set_Is_Internal (Ent);
4567
ee6ba406 4568 Rewrite (N,
4569 Make_Attribute_Reference (Loc,
4570 Prefix => New_Occurrence_Of (Ent, Loc),
4571 Attribute_Name => Name_Address));
4572
4573 Analyze_And_Resolve (N, Typ);
4574 end UET_Address;
4575
ee6ba406 4576 ---------------
4577 -- VADS_Size --
4578 ---------------
4579
4580 -- The processing for VADS_Size is shared with Size
4581
4582 ---------
4583 -- Val --
4584 ---------
4585
4586 -- For enumeration types with a standard representation, and for all
d55c93e0 4587 -- other types, Val is handled by the back end. For enumeration types
4588 -- with a non-standard representation we use the _Pos_To_Rep array that
ee6ba406 4589 -- was created when the type was frozen.
4590
4591 when Attribute_Val => Val :
4592 declare
4593 Etyp : constant Entity_Id := Base_Type (Entity (Pref));
4594
4595 begin
4596 if Is_Enumeration_Type (Etyp)
4597 and then Present (Enum_Pos_To_Rep (Etyp))
4598 then
9dfe12ae 4599 if Has_Contiguous_Rep (Etyp) then
4600 declare
4601 Rep_Node : constant Node_Id :=
4602 Unchecked_Convert_To (Etyp,
4603 Make_Op_Add (Loc,
4604 Left_Opnd =>
4605 Make_Integer_Literal (Loc,
4606 Enumeration_Rep (First_Literal (Etyp))),
4607 Right_Opnd =>
4608 (Convert_To (Standard_Integer,
4609 Relocate_Node (First (Exprs))))));
4610
4611 begin
4612 Rewrite (N,
4613 Unchecked_Convert_To (Etyp,
4614 Make_Op_Add (Loc,
4615 Left_Opnd =>
4616 Make_Integer_Literal (Loc,
4617 Enumeration_Rep (First_Literal (Etyp))),
4618 Right_Opnd =>
4619 Make_Function_Call (Loc,
4620 Name =>
4621 New_Reference_To
4622 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4623 Parameter_Associations => New_List (
4624 Rep_Node,
4625 Rep_To_Pos_Flag (Etyp, Loc))))));
4626 end;
4627
4628 else
4629 Rewrite (N,
4630 Make_Indexed_Component (Loc,
4631 Prefix => New_Reference_To (Enum_Pos_To_Rep (Etyp), Loc),
4632 Expressions => New_List (
4633 Convert_To (Standard_Integer,
4634 Relocate_Node (First (Exprs))))));
4635 end if;
ee6ba406 4636
4637 Analyze_And_Resolve (N, Typ);
a9b57347 4638
4639 -- If the argument is marked as requiring a range check then generate
4640 -- it here.
4641
4642 elsif Do_Range_Check (First (Exprs)) then
4643 Set_Do_Range_Check (First (Exprs), False);
4644 Generate_Range_Check (First (Exprs), Etyp, CE_Range_Check_Failed);
ee6ba406 4645 end if;
4646 end Val;
4647
4648 -----------
4649 -- Valid --
4650 -----------
4651
4652 -- The code for valid is dependent on the particular types involved.
4653 -- See separate sections below for the generated code in each case.
4654
4655 when Attribute_Valid => Valid :
4656 declare
d55c93e0 4657 Btyp : Entity_Id := Base_Type (Ptyp);
ee6ba406 4658 Tst : Node_Id;
4659
9dfe12ae 4660 Save_Validity_Checks_On : constant Boolean := Validity_Checks_On;
4661 -- Save the validity checking mode. We always turn off validity
4662 -- checking during process of 'Valid since this is one place
4663 -- where we do not want the implicit validity checks to intefere
4664 -- with the explicit validity check that the programmer is doing.
4665
ee6ba406 4666 function Make_Range_Test return Node_Id;
4667 -- Build the code for a range test of the form
4668 -- Btyp!(Pref) >= Btyp!(Ptyp'First)
4669 -- and then
4670 -- Btyp!(Pref) <= Btyp!(Ptyp'Last)
4671
9dfe12ae 4672 ---------------------
4673 -- Make_Range_Test --
4674 ---------------------
4675
ee6ba406 4676 function Make_Range_Test return Node_Id is
4677 begin
4678 return
4679 Make_And_Then (Loc,
4680 Left_Opnd =>
4681 Make_Op_Ge (Loc,
4682 Left_Opnd =>
4683 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
4684
4685 Right_Opnd =>
4686 Unchecked_Convert_To (Btyp,
4687 Make_Attribute_Reference (Loc,
4688 Prefix => New_Occurrence_Of (Ptyp, Loc),
4689 Attribute_Name => Name_First))),
4690
4691 Right_Opnd =>
4692 Make_Op_Le (Loc,
4693 Left_Opnd =>
9dfe12ae 4694 Unchecked_Convert_To (Btyp,
4695 Duplicate_Subexpr_No_Checks (Pref)),
ee6ba406 4696
4697 Right_Opnd =>
4698 Unchecked_Convert_To (Btyp,
4699 Make_Attribute_Reference (Loc,
4700 Prefix => New_Occurrence_Of (Ptyp, Loc),
4701 Attribute_Name => Name_Last))));
4702 end Make_Range_Test;
4703
4704 -- Start of processing for Attribute_Valid
4705
4706 begin
9dfe12ae 4707 -- Turn off validity checks. We do not want any implicit validity
4708 -- checks to intefere with the explicit check from the attribute
4709
4710 Validity_Checks_On := False;
4711
ee6ba406 4712 -- Floating-point case. This case is handled by the Valid attribute
4713 -- code in the floating-point attribute run-time library.
4714
4715 if Is_Floating_Point_Type (Ptyp) then
4716 declare
1550b445 4717 Pkg : RE_Id;
4718 Ftp : Entity_Id;
ee6ba406 4719
4720 begin
6e62b6c3 4721 -- For vax fpt types, call appropriate routine in special vax
4722 -- floating point unit. We do not have to worry about loads in
4723 -- this case, since these types have no signalling NaN's.
4724
1550b445 4725 if Vax_Float (Btyp) then
6e62b6c3 4726 Expand_Vax_Valid (N);
4727
7f8eb6ed 4728 -- The AAMP back end handles Valid for floating-point types
4729
4730 elsif Is_AAMP_Float (Btyp) then
4731 Analyze_And_Resolve (Pref, Ptyp);
4732 Set_Etype (N, Standard_Boolean);
4733 Set_Analyzed (N);
4734
1550b445 4735 -- Non VAX float case
9dfe12ae 4736
1550b445 4737 else
d55c93e0 4738 Find_Fat_Info (Ptyp, Ftp, Pkg);
1550b445 4739
4740 -- If the floating-point object might be unaligned, we need
4741 -- to call the special routine Unaligned_Valid, which makes
4742 -- the needed copy, being careful not to load the value into
4743 -- any floating-point register. The argument in this case is
99f2248e 4744 -- obj'Address (see Unaligned_Valid routine in Fat_Gen).
1550b445 4745
4746 if Is_Possibly_Unaligned_Object (Pref) then
1550b445 4747 Expand_Fpt_Attribute
4748 (N, Pkg, Name_Unaligned_Valid,
4749 New_List (
4750 Make_Attribute_Reference (Loc,
4751 Prefix => Relocate_Node (Pref),
4752 Attribute_Name => Name_Address)));
9dfe12ae 4753
1550b445 4754 -- In the normal case where we are sure the object is
4755 -- aligned, we generate a call to Valid, and the argument in
4756 -- this case is obj'Unrestricted_Access (after converting
4757 -- obj to the right floating-point type).
9dfe12ae 4758
1550b445 4759 else
4760 Expand_Fpt_Attribute
4761 (N, Pkg, Name_Valid,
4762 New_List (
4763 Make_Attribute_Reference (Loc,
4764 Prefix => Unchecked_Convert_To (Ftp, Pref),
4765 Attribute_Name => Name_Unrestricted_Access)));
4766 end if;
9dfe12ae 4767 end if;
ee6ba406 4768
4769 -- One more task, we still need a range check. Required
4770 -- only if we have a constraint, since the Valid routine
4771 -- catches infinities properly (infinities are never valid).
4772
4773 -- The way we do the range check is simply to create the
4774 -- expression: Valid (N) and then Base_Type(Pref) in Typ.
4775
4776 if not Subtypes_Statically_Match (Ptyp, Btyp) then
4777 Rewrite (N,
4778 Make_And_Then (Loc,
4779 Left_Opnd => Relocate_Node (N),
4780 Right_Opnd =>
4781 Make_In (Loc,
4782 Left_Opnd => Convert_To (Btyp, Pref),
4783 Right_Opnd => New_Occurrence_Of (Ptyp, Loc))));
4784 end if;
4785 end;
4786
4787 -- Enumeration type with holes
4788
4789 -- For enumeration types with holes, the Pos value constructed by
4790 -- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a
4791 -- second argument of False returns minus one for an invalid value,
4792 -- and the non-negative pos value for a valid value, so the
4793 -- expansion of X'Valid is simply:
4794
4795 -- type(X)'Pos (X) >= 0
4796
4797 -- We can't quite generate it that way because of the requirement
5329ca64 4798 -- for the non-standard second argument of False in the resulting
4799 -- rep_to_pos call, so we have to explicitly create:
ee6ba406 4800
4801 -- _rep_to_pos (X, False) >= 0
4802
4803 -- If we have an enumeration subtype, we also check that the
4804 -- value is in range:
4805
4806 -- _rep_to_pos (X, False) >= 0
4807 -- and then
5329ca64 4808 -- (X >= type(X)'First and then type(X)'Last <= X)
ee6ba406 4809
4810 elsif Is_Enumeration_Type (Ptyp)
4811 and then Present (Enum_Pos_To_Rep (Base_Type (Ptyp)))
4812 then
4813 Tst :=
4814 Make_Op_Ge (Loc,
4815 Left_Opnd =>
4816 Make_Function_Call (Loc,
4817 Name =>
4818 New_Reference_To
9dfe12ae 4819 (TSS (Base_Type (Ptyp), TSS_Rep_To_Pos), Loc),
ee6ba406 4820 Parameter_Associations => New_List (
4821 Pref,
4822 New_Occurrence_Of (Standard_False, Loc))),
4823 Right_Opnd => Make_Integer_Literal (Loc, 0));
4824
4825 if Ptyp /= Btyp
4826 and then
4827 (Type_Low_Bound (Ptyp) /= Type_Low_Bound (Btyp)
4828 or else
4829 Type_High_Bound (Ptyp) /= Type_High_Bound (Btyp))
4830 then
4831 -- The call to Make_Range_Test will create declarations
4832 -- that need a proper insertion point, but Pref is now
4833 -- attached to a node with no ancestor. Attach to tree
4834 -- even if it is to be rewritten below.
4835
4836 Set_Parent (Tst, Parent (N));
4837
4838 Tst :=
4839 Make_And_Then (Loc,
4840 Left_Opnd => Make_Range_Test,
4841 Right_Opnd => Tst);
4842 end if;
4843
4844 Rewrite (N, Tst);
4845
4846 -- Fortran convention booleans
4847
4848 -- For the very special case of Fortran convention booleans, the
4849 -- value is always valid, since it is an integer with the semantics
4850 -- that non-zero is true, and any value is permissible.
4851
4852 elsif Is_Boolean_Type (Ptyp)
4853 and then Convention (Ptyp) = Convention_Fortran
4854 then
4855 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
4856
4857 -- For biased representations, we will be doing an unchecked
aad6babd 4858 -- conversion without unbiasing the result. That means that the range
4859 -- test has to take this into account, and the proper form of the
4860 -- test is:
ee6ba406 4861
4862 -- Btyp!(Pref) < Btyp!(Ptyp'Range_Length)
4863
4864 elsif Has_Biased_Representation (Ptyp) then
4865 Btyp := RTE (RE_Unsigned_32);
4866 Rewrite (N,
4867 Make_Op_Lt (Loc,
4868 Left_Opnd =>
4869 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
4870 Right_Opnd =>
4871 Unchecked_Convert_To (Btyp,
4872 Make_Attribute_Reference (Loc,
4873 Prefix => New_Occurrence_Of (Ptyp, Loc),
4874 Attribute_Name => Name_Range_Length))));
4875
4876 -- For all other scalar types, what we want logically is a
4877 -- range test:
4878
4879 -- X in type(X)'First .. type(X)'Last
4880
4881 -- But that's precisely what won't work because of possible
4882 -- unwanted optimization (and indeed the basic motivation for
5329ca64 4883 -- the Valid attribute is exactly that this test does not work!)
ee6ba406 4884 -- What will work is:
4885
4886 -- Btyp!(X) >= Btyp!(type(X)'First)
4887 -- and then
4888 -- Btyp!(X) <= Btyp!(type(X)'Last)
4889
4890 -- where Btyp is an integer type large enough to cover the full
4891 -- range of possible stored values (i.e. it is chosen on the basis
4892 -- of the size of the type, not the range of the values). We write
4893 -- this as two tests, rather than a range check, so that static
4894 -- evaluation will easily remove either or both of the checks if
4895 -- they can be -statically determined to be true (this happens
4896 -- when the type of X is static and the range extends to the full
4897 -- range of stored values).
4898
4899 -- Unsigned types. Note: it is safe to consider only whether the
4900 -- subtype is unsigned, since we will in that case be doing all
aad6babd 4901 -- unsigned comparisons based on the subtype range. Since we use the
4902 -- actual subtype object size, this is appropriate.
ee6ba406 4903
4904 -- For example, if we have
4905
4906 -- subtype x is integer range 1 .. 200;
4907 -- for x'Object_Size use 8;
4908
aad6babd 4909 -- Now the base type is signed, but objects of this type are bits
4910 -- unsigned, and doing an unsigned test of the range 1 to 200 is
4911 -- correct, even though a value greater than 127 looks signed to a
4912 -- signed comparison.
ee6ba406 4913
4914 elsif Is_Unsigned_Type (Ptyp) then
4915 if Esize (Ptyp) <= 32 then
4916 Btyp := RTE (RE_Unsigned_32);
4917 else
4918 Btyp := RTE (RE_Unsigned_64);
4919 end if;
4920
4921 Rewrite (N, Make_Range_Test);
4922
4923 -- Signed types
4924
4925 else
4926 if Esize (Ptyp) <= Esize (Standard_Integer) then
4927 Btyp := Standard_Integer;
4928 else
4929 Btyp := Universal_Integer;
4930 end if;
4931
4932 Rewrite (N, Make_Range_Test);
4933 end if;
4934
4935 Analyze_And_Resolve (N, Standard_Boolean);
9dfe12ae 4936 Validity_Checks_On := Save_Validity_Checks_On;
ee6ba406 4937 end Valid;
4938
4939 -----------
4940 -- Value --
4941 -----------
4942
4943 -- Value attribute is handled in separate unti Exp_Imgv
4944
4945 when Attribute_Value =>
4946 Exp_Imgv.Expand_Value_Attribute (N);
4947
4948 -----------------
4949 -- Value_Size --
4950 -----------------
4951
4952 -- The processing for Value_Size shares the processing for Size
4953
4954 -------------
4955 -- Version --
4956 -------------
4957
4958 -- The processing for Version shares the processing for Body_Version
4959
4960 ----------------
4961 -- Wide_Image --
4962 ----------------
4963
f0bf2ff3 4964 -- Wide_Image attribute is handled in separate unit Exp_Imgv
ee6ba406 4965
f0bf2ff3 4966 when Attribute_Wide_Image =>
4967 Exp_Imgv.Expand_Wide_Image_Attribute (N);
ee6ba406 4968
7189d17f 4969 ---------------------
4970 -- Wide_Wide_Image --
4971 ---------------------
4972
f0bf2ff3 4973 -- Wide_Wide_Image attribute is handled in separate unit Exp_Imgv
7189d17f 4974
f0bf2ff3 4975 when Attribute_Wide_Wide_Image =>
4976 Exp_Imgv.Expand_Wide_Wide_Image_Attribute (N);
7189d17f 4977
ee6ba406 4978 ----------------
4979 -- Wide_Value --
4980 ----------------
4981
4982 -- We expand typ'Wide_Value (X) into
4983
4984 -- typ'Value
4985 -- (Wide_String_To_String (X, Wide_Character_Encoding_Method))
4986
4987 -- Wide_String_To_String is a runtime function that converts its wide
4988 -- string argument to String, converting any non-translatable characters
4989 -- into appropriate escape sequences. This preserves the required
4990 -- semantics of Wide_Value in all cases, and results in a very simple
4991 -- implementation approach.
4992
7f8eb6ed 4993 -- Note: for this approach to be fully standard compliant for the cases
4994 -- where typ is Wide_Character and Wide_Wide_Character, the encoding
4995 -- method must cover the entire character range (e.g. UTF-8). But that
4996 -- is a reasonable requirement when dealing with encoded character
4997 -- sequences. Presumably if one of the restrictive encoding mechanisms
4998 -- is in use such as Shift-JIS, then characters that cannot be
4999 -- represented using this encoding will not appear in any case.
ee6ba406 5000
5001 when Attribute_Wide_Value => Wide_Value :
5002 begin
5003 Rewrite (N,
5004 Make_Attribute_Reference (Loc,
5005 Prefix => Pref,
5006 Attribute_Name => Name_Value,
5007
5008 Expressions => New_List (
5009 Make_Function_Call (Loc,
5010 Name =>
5011 New_Reference_To (RTE (RE_Wide_String_To_String), Loc),
5012
5013 Parameter_Associations => New_List (
5014 Relocate_Node (First (Exprs)),
5015 Make_Integer_Literal (Loc,
5016 Intval => Int (Wide_Character_Encoding_Method)))))));
5017
5018 Analyze_And_Resolve (N, Typ);
5019 end Wide_Value;
5020
7189d17f 5021 ---------------------
5022 -- Wide_Wide_Value --
5023 ---------------------
5024
5025 -- We expand typ'Wide_Value_Value (X) into
5026
5027 -- typ'Value
5028 -- (Wide_Wide_String_To_String (X, Wide_Character_Encoding_Method))
5029
5030 -- Wide_Wide_String_To_String is a runtime function that converts its
5031 -- wide string argument to String, converting any non-translatable
5032 -- characters into appropriate escape sequences. This preserves the
5033 -- required semantics of Wide_Wide_Value in all cases, and results in a
5034 -- very simple implementation approach.
5035
5036 -- It's not quite right where typ = Wide_Wide_Character, because the
5037 -- encoding method may not cover the whole character type ???
5038
5039 when Attribute_Wide_Wide_Value => Wide_Wide_Value :
5040 begin
5041 Rewrite (N,
5042 Make_Attribute_Reference (Loc,
5043 Prefix => Pref,
5044 Attribute_Name => Name_Value,
5045
5046 Expressions => New_List (
5047 Make_Function_Call (Loc,
5048 Name =>
5049 New_Reference_To (RTE (RE_Wide_Wide_String_To_String), Loc),
5050
5051 Parameter_Associations => New_List (
5052 Relocate_Node (First (Exprs)),
5053 Make_Integer_Literal (Loc,
5054 Intval => Int (Wide_Character_Encoding_Method)))))));
5055
5056 Analyze_And_Resolve (N, Typ);
5057 end Wide_Wide_Value;
5058
5059 ---------------------
5060 -- Wide_Wide_Width --
5061 ---------------------
5062
5063 -- Wide_Wide_Width attribute is handled in separate unit Exp_Imgv
5064
5065 when Attribute_Wide_Wide_Width =>
5066 Exp_Imgv.Expand_Width_Attribute (N, Wide_Wide);
5067
ee6ba406 5068 ----------------
5069 -- Wide_Width --
5070 ----------------
5071
5072 -- Wide_Width attribute is handled in separate unit Exp_Imgv
5073
5074 when Attribute_Wide_Width =>
7189d17f 5075 Exp_Imgv.Expand_Width_Attribute (N, Wide);
ee6ba406 5076
5077 -----------
5078 -- Width --
5079 -----------
5080
5081 -- Width attribute is handled in separate unit Exp_Imgv
5082
5083 when Attribute_Width =>
7189d17f 5084 Exp_Imgv.Expand_Width_Attribute (N, Normal);
ee6ba406 5085
5086 -----------
5087 -- Write --
5088 -----------
5089
5090 when Attribute_Write => Write : declare
5091 P_Type : constant Entity_Id := Entity (Pref);
5092 U_Type : constant Entity_Id := Underlying_Type (P_Type);
5093 Pname : Entity_Id;
5094 Decl : Node_Id;
5095 Prag : Node_Id;
5096 Arg3 : Node_Id;
5097 Wfunc : Node_Id;
5098
5099 begin
5100 -- If no underlying type, we have an error that will be diagnosed
5101 -- elsewhere, so here we just completely ignore the expansion.
5102
5103 if No (U_Type) then
5104 return;
5105 end if;
5106
5107 -- The simple case, if there is a TSS for Write, just call it
5108
9dfe12ae 5109 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Write);
ee6ba406 5110
5111 if Present (Pname) then
5112 null;
5113
5114 else
5115 -- If there is a Stream_Convert pragma, use it, we rewrite
5116
5117 -- sourcetyp'Output (stream, Item)
5118
5119 -- as
5120
5121 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
5122
aad6babd 5123 -- where strmwrite is the given Write function that converts an
5124 -- argument of type sourcetyp or a type acctyp, from which it is
5125 -- derived to type strmtyp. The conversion to acttyp is required
5126 -- for the derived case.
ee6ba406 5127
5245b786 5128 Prag := Get_Stream_Convert_Pragma (P_Type);
ee6ba406 5129
5130 if Present (Prag) then
5131 Arg3 :=
5132 Next (Next (First (Pragma_Argument_Associations (Prag))));
5133 Wfunc := Entity (Expression (Arg3));
5134
5135 Rewrite (N,
5136 Make_Attribute_Reference (Loc,
5137 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
5138 Attribute_Name => Name_Output,
5139 Expressions => New_List (
5140 Relocate_Node (First (Exprs)),
5141 Make_Function_Call (Loc,
5142 Name => New_Occurrence_Of (Wfunc, Loc),
5143 Parameter_Associations => New_List (
83aa52b6 5144 OK_Convert_To (Etype (First_Formal (Wfunc)),
ee6ba406 5145 Relocate_Node (Next (First (Exprs)))))))));
5146
5147 Analyze (N);
5148 return;
5149
5150 -- For elementary types, we call the W_xxx routine directly
5151
5152 elsif Is_Elementary_Type (U_Type) then
5153 Rewrite (N, Build_Elementary_Write_Call (N));
5154 Analyze (N);
5155 return;
5156
5157 -- Array type case
5158
5159 elsif Is_Array_Type (U_Type) then
5160 Build_Array_Write_Procedure (N, U_Type, Decl, Pname);
5161 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
5162
5163 -- Tagged type case, use the primitive Write function. Note that
5164 -- this will dispatch in the class-wide case which is what we want
5165
5166 elsif Is_Tagged_Type (U_Type) then
9dfe12ae 5167 Pname := Find_Prim_Op (U_Type, TSS_Stream_Write);
ee6ba406 5168
5169 -- All other record type cases, including protected records.
5170 -- The latter only arise for expander generated code for
5171 -- handling shared passive partition access.
5172
5173 else
5174 pragma Assert
5175 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
5176
00f91aef 5177 -- Ada 2005 (AI-216): Program_Error is raised when executing
5178 -- the default implementation of the Write attribute of an
99f2248e 5179 -- Unchecked_Union type. However, if the 'Write reference is
5180 -- within the generated Output stream procedure, Write outputs
5181 -- the components, and the default values of the discriminant
5182 -- are streamed by the Output procedure itself.
00f91aef 5183
99f2248e 5184 if Is_Unchecked_Union (Base_Type (U_Type))
5185 and not Is_TSS (Current_Scope, TSS_Stream_Output)
5186 then
00f91aef 5187 Insert_Action (N,
5188 Make_Raise_Program_Error (Loc,
5189 Reason => PE_Unchecked_Union_Restriction));
5190 end if;
5191
ee6ba406 5192 if Has_Discriminants (U_Type)
5193 and then Present
5194 (Discriminant_Default_Value (First_Discriminant (U_Type)))
5195 then
5196 Build_Mutable_Record_Write_Procedure
5197 (Loc, Base_Type (U_Type), Decl, Pname);
ee6ba406 5198 else
5199 Build_Record_Write_Procedure
5200 (Loc, Base_Type (U_Type), Decl, Pname);
5201 end if;
5202
5203 Insert_Action (N, Decl);
5204 end if;
5205 end if;
5206
5207 -- If we fall through, Pname is the procedure to be called
5208
5209 Rewrite_Stream_Proc_Call (Pname);
5210 end Write;
5211
d55c93e0 5212 -- Component_Size is handled by the back end, unless the component size
5213 -- is known at compile time, which is always true in the packed array
5214 -- case. It is important that the packed array case is handled in the
5215 -- front end (see Eval_Attribute) since the back end would otherwise get
5216 -- confused by the equivalent packed array type.
ee6ba406 5217
5218 when Attribute_Component_Size =>
5219 null;
5220
18a40e97 5221 -- The following attributes are handled by the back end (except that
5222 -- static cases have already been evaluated during semantic processing,
5223 -- but in any case the back end should not count on this). The one bit
5224 -- of special processing required is that these attributes typically
5225 -- generate conditionals in the code, so we need to check the relevant
5226 -- restriction.
5227
5228 when Attribute_Max |
5229 Attribute_Min =>
5230 Check_Restriction (No_Implicit_Conditionals, N);
ee6ba406 5231
18a40e97 5232 -- The following attributes are handled by the back end (except that
5233 -- static cases have already been evaluated during semantic processing,
5234 -- but in any case the back end should not count on this).
ee6ba406 5235
d55c93e0 5236 -- The back end also handles the non-class-wide cases of Size
ee6ba406 5237
5238 when Attribute_Bit_Order |
5239 Attribute_Code_Address |
5240 Attribute_Definite |
ee6ba406 5241 Attribute_Null_Parameter |
9dfe12ae 5242 Attribute_Passed_By_Reference |
5243 Attribute_Pool_Address =>
ee6ba406 5244 null;
5245
d55c93e0 5246 -- The following attributes are also handled by the back end, but return
5247 -- a universal integer result, so may need a conversion for checking
ee6ba406 5248 -- that the result is in range.
5249
5250 when Attribute_Aft |
ee6ba406 5251 Attribute_Bit |
5252 Attribute_Max_Size_In_Storage_Elements
5253 =>
5254 Apply_Universal_Integer_Attribute_Checks (N);
5255
5256 -- The following attributes should not appear at this stage, since they
5257 -- have already been handled by the analyzer (and properly rewritten
5258 -- with corresponding values or entities to represent the right values)
5259
5260 when Attribute_Abort_Signal |
5261 Attribute_Address_Size |
5262 Attribute_Base |
5263 Attribute_Class |
a79db212 5264 Attribute_Compiler_Version |
ee6ba406 5265 Attribute_Default_Bit_Order |
5266 Attribute_Delta |
5267 Attribute_Denorm |
5268 Attribute_Digits |
5269 Attribute_Emax |
f947f061 5270 Attribute_Enabled |
ee6ba406 5271 Attribute_Epsilon |
f0bf2ff3 5272 Attribute_Fast_Math |
5c99c290 5273 Attribute_Has_Access_Values |
ee6ba406 5274 Attribute_Has_Discriminants |
d55c93e0 5275 Attribute_Has_Tagged_Values |
ee6ba406 5276 Attribute_Large |
5277 Attribute_Machine_Emax |
5278 Attribute_Machine_Emin |
5279 Attribute_Machine_Mantissa |
5280 Attribute_Machine_Overflows |
5281 Attribute_Machine_Radix |
5282 Attribute_Machine_Rounds |
ee6ba406 5283 Attribute_Maximum_Alignment |
5284 Attribute_Model_Emin |
5285 Attribute_Model_Epsilon |
5286 Attribute_Model_Mantissa |
5287 Attribute_Model_Small |
5288 Attribute_Modulus |
5289 Attribute_Partition_ID |
5290 Attribute_Range |
5291 Attribute_Safe_Emax |
5292 Attribute_Safe_First |
5293 Attribute_Safe_Large |
5294 Attribute_Safe_Last |
5295 Attribute_Safe_Small |
5296 Attribute_Scale |
5297 Attribute_Signed_Zeros |
5298 Attribute_Small |
5299 Attribute_Storage_Unit |
7f8eb6ed 5300 Attribute_Stub_Type |
9dfe12ae 5301 Attribute_Target_Name |
ee6ba406 5302 Attribute_Type_Class |
9dfe12ae 5303 Attribute_Unconstrained_Array |
ee6ba406 5304 Attribute_Universal_Literal_String |
5305 Attribute_Wchar_T_Size |
5306 Attribute_Word_Size =>
5307
5308 raise Program_Error;
5309
5310 -- The Asm_Input and Asm_Output attributes are not expanded at this
d55c93e0 5311 -- stage, but will be eliminated in the expansion of the Asm call, see
5312 -- Exp_Intr for details. So the back end will never see these either.
ee6ba406 5313
5314 when Attribute_Asm_Input |
5315 Attribute_Asm_Output =>
5316
5317 null;
5318
5319 end case;
5320
9dfe12ae 5321 exception
5322 when RE_Not_Available =>
5323 return;
ee6ba406 5324 end Expand_N_Attribute_Reference;
5325
5326 ----------------------
5327 -- Expand_Pred_Succ --
5328 ----------------------
5329
5330 -- For typ'Pred (exp), we generate the check
5331
5332 -- [constraint_error when exp = typ'Base'First]
5333
5334 -- Similarly, for typ'Succ (exp), we generate the check
5335
5336 -- [constraint_error when exp = typ'Base'Last]
5337
5338 -- These checks are not generated for modular types, since the proper
5339 -- semantics for Succ and Pred on modular types is to wrap, not raise CE.
5340
5341 procedure Expand_Pred_Succ (N : Node_Id) is
5342 Loc : constant Source_Ptr := Sloc (N);
5343 Cnam : Name_Id;
5344
5345 begin
5346 if Attribute_Name (N) = Name_Pred then
5347 Cnam := Name_First;
5348 else
5349 Cnam := Name_Last;
5350 end if;
5351
5352 Insert_Action (N,
5353 Make_Raise_Constraint_Error (Loc,
5354 Condition =>
5355 Make_Op_Eq (Loc,
9dfe12ae 5356 Left_Opnd =>
5357 Duplicate_Subexpr_Move_Checks (First (Expressions (N))),
ee6ba406 5358 Right_Opnd =>
5359 Make_Attribute_Reference (Loc,
5360 Prefix =>
5361 New_Reference_To (Base_Type (Etype (Prefix (N))), Loc),
f15731c4 5362 Attribute_Name => Cnam)),
5363 Reason => CE_Overflow_Check_Failed));
ee6ba406 5364 end Expand_Pred_Succ;
5365
1550b445 5366 -------------------
5367 -- Find_Fat_Info --
5368 -------------------
5369
5370 procedure Find_Fat_Info
5371 (T : Entity_Id;
5372 Fat_Type : out Entity_Id;
5373 Fat_Pkg : out RE_Id)
5374 is
5375 Btyp : constant Entity_Id := Base_Type (T);
5376 Rtyp : constant Entity_Id := Root_Type (T);
5377 Digs : constant Nat := UI_To_Int (Digits_Value (Btyp));
5378
5379 begin
5380 -- If the base type is VAX float, then get appropriate VAX float type
5381
5382 if Vax_Float (Btyp) then
5383 case Digs is
5384 when 6 =>
5385 Fat_Type := RTE (RE_Fat_VAX_F);
5386 Fat_Pkg := RE_Attr_VAX_F_Float;
5387
5388 when 9 =>
5389 Fat_Type := RTE (RE_Fat_VAX_D);
5390 Fat_Pkg := RE_Attr_VAX_D_Float;
5391
5392 when 15 =>
5393 Fat_Type := RTE (RE_Fat_VAX_G);
5394 Fat_Pkg := RE_Attr_VAX_G_Float;
5395
5396 when others =>
5397 raise Program_Error;
5398 end case;
5399
5400 -- If root type is VAX float, this is the case where the library has
5401 -- been recompiled in VAX float mode, and we have an IEEE float type.
5402 -- This is when we use the special IEEE Fat packages.
5403
5404 elsif Vax_Float (Rtyp) then
5405 case Digs is
5406 when 6 =>
5407 Fat_Type := RTE (RE_Fat_IEEE_Short);
5408 Fat_Pkg := RE_Attr_IEEE_Short;
5409
5410 when 15 =>
5411 Fat_Type := RTE (RE_Fat_IEEE_Long);
5412 Fat_Pkg := RE_Attr_IEEE_Long;
5413
5414 when others =>
5415 raise Program_Error;
5416 end case;
5417
5418 -- If neither the base type nor the root type is VAX_Float then VAX
5419 -- float is out of the picture, and we can just use the root type.
5420
5421 else
5422 Fat_Type := Rtyp;
5423
5424 if Fat_Type = Standard_Short_Float then
5425 Fat_Pkg := RE_Attr_Short_Float;
7f8eb6ed 5426
1550b445 5427 elsif Fat_Type = Standard_Float then
5428 Fat_Pkg := RE_Attr_Float;
7f8eb6ed 5429
1550b445 5430 elsif Fat_Type = Standard_Long_Float then
5431 Fat_Pkg := RE_Attr_Long_Float;
7f8eb6ed 5432
1550b445 5433 elsif Fat_Type = Standard_Long_Long_Float then
5434 Fat_Pkg := RE_Attr_Long_Long_Float;
7f8eb6ed 5435
5436 -- Universal real (which is its own root type) is treated as being
5437 -- equivalent to Standard.Long_Long_Float, since it is defined to
5438 -- have the same precision as the longest Float type.
5439
5440 elsif Fat_Type = Universal_Real then
5441 Fat_Type := Standard_Long_Long_Float;
5442 Fat_Pkg := RE_Attr_Long_Long_Float;
5443
1550b445 5444 else
5445 raise Program_Error;
5446 end if;
5447 end if;
5448 end Find_Fat_Info;
5449
9dfe12ae 5450 ----------------------------
5451 -- Find_Stream_Subprogram --
5452 ----------------------------
5453
5454 function Find_Stream_Subprogram
5455 (Typ : Entity_Id;
aad6babd 5456 Nam : TSS_Name_Type) return Entity_Id
5457 is
8667b0b2 5458 Base_Typ : constant Entity_Id := Base_Type (Typ);
5459 Ent : constant Entity_Id := TSS (Typ, Nam);
d55c93e0 5460
9dfe12ae 5461 begin
aad6babd 5462 if Present (Ent) then
5463 return Ent;
5464 end if;
5465
d55c93e0 5466 -- Stream attributes for strings are expanded into library calls. The
5467 -- following checks are disabled when the run-time is not available or
5468 -- when compiling predefined types due to bootstrap issues. As a result,
5469 -- the compiler will generate in-place stream routines for string types
5470 -- that appear in GNAT's library, but will generate calls via rtsfind
5471 -- to library routines for user code.
5472 -- ??? For now, disable this code for JVM, since this generates a
5473 -- VerifyError exception at run-time on e.g. c330001.
5474 -- This is disabled for AAMP, to avoid making dependences on files not
5475 -- supported in the AAMP library (such as s-fileio.adb).
5476
5477 if VM_Target /= JVM_Target
5478 and then not AAMP_On_Target
5479 and then
5480 not Is_Predefined_File_Name (Unit_File_Name (Current_Sem_Unit))
5481 then
d55c93e0 5482 -- String as defined in package Ada
5483
8667b0b2 5484 if Base_Typ = Standard_String then
b9f24e67 5485 if Restriction_Active (No_Stream_Optimizations) then
5486 if Nam = TSS_Stream_Input then
5487 return RTE (RE_String_Input);
5488
5489 elsif Nam = TSS_Stream_Output then
5490 return RTE (RE_String_Output);
5491
5492 elsif Nam = TSS_Stream_Read then
5493 return RTE (RE_String_Read);
d55c93e0 5494
b9f24e67 5495 else pragma Assert (Nam = TSS_Stream_Write);
5496 return RTE (RE_String_Write);
5497 end if;
5498
5499 else
5500 if Nam = TSS_Stream_Input then
5501 return RTE (RE_String_Input_Blk_IO);
d55c93e0 5502
b9f24e67 5503 elsif Nam = TSS_Stream_Output then
5504 return RTE (RE_String_Output_Blk_IO);
d55c93e0 5505
b9f24e67 5506 elsif Nam = TSS_Stream_Read then
5507 return RTE (RE_String_Read_Blk_IO);
5508
5509 else pragma Assert (Nam = TSS_Stream_Write);
5510 return RTE (RE_String_Write_Blk_IO);
5511 end if;
d55c93e0 5512 end if;
5513
5514 -- Wide_String as defined in package Ada
5515
8667b0b2 5516 elsif Base_Typ = Standard_Wide_String then
b9f24e67 5517 if Restriction_Active (No_Stream_Optimizations) then
5518 if Nam = TSS_Stream_Input then
5519 return RTE (RE_Wide_String_Input);
5520
5521 elsif Nam = TSS_Stream_Output then
5522 return RTE (RE_Wide_String_Output);
5523
5524 elsif Nam = TSS_Stream_Read then
5525 return RTE (RE_Wide_String_Read);
5526
5527 else pragma Assert (Nam = TSS_Stream_Write);
5528 return RTE (RE_Wide_String_Write);
5529 end if;
5530
5531 else
5532 if Nam = TSS_Stream_Input then
5533 return RTE (RE_Wide_String_Input_Blk_IO);
d55c93e0 5534
b9f24e67 5535 elsif Nam = TSS_Stream_Output then
5536 return RTE (RE_Wide_String_Output_Blk_IO);
d55c93e0 5537
b9f24e67 5538 elsif Nam = TSS_Stream_Read then
5539 return RTE (RE_Wide_String_Read_Blk_IO);
d55c93e0 5540
b9f24e67 5541 else pragma Assert (Nam = TSS_Stream_Write);
5542 return RTE (RE_Wide_String_Write_Blk_IO);
5543 end if;
d55c93e0 5544 end if;
5545
5546 -- Wide_Wide_String as defined in package Ada
5547
8667b0b2 5548 elsif Base_Typ = Standard_Wide_Wide_String then
b9f24e67 5549 if Restriction_Active (No_Stream_Optimizations) then
5550 if Nam = TSS_Stream_Input then
5551 return RTE (RE_Wide_Wide_String_Input);
5552
5553 elsif Nam = TSS_Stream_Output then
5554 return RTE (RE_Wide_Wide_String_Output);
d55c93e0 5555
b9f24e67 5556 elsif Nam = TSS_Stream_Read then
5557 return RTE (RE_Wide_Wide_String_Read);
d55c93e0 5558
b9f24e67 5559 else pragma Assert (Nam = TSS_Stream_Write);
5560 return RTE (RE_Wide_Wide_String_Write);
5561 end if;
d55c93e0 5562
b9f24e67 5563 else
5564 if Nam = TSS_Stream_Input then
5565 return RTE (RE_Wide_Wide_String_Input_Blk_IO);
5566
5567 elsif Nam = TSS_Stream_Output then
5568 return RTE (RE_Wide_Wide_String_Output_Blk_IO);
5569
5570 elsif Nam = TSS_Stream_Read then
5571 return RTE (RE_Wide_Wide_String_Read_Blk_IO);
5572
5573 else pragma Assert (Nam = TSS_Stream_Write);
5574 return RTE (RE_Wide_Wide_String_Write_Blk_IO);
5575 end if;
d55c93e0 5576 end if;
5577 end if;
5578 end if;
5579
9dfe12ae 5580 if Is_Tagged_Type (Typ)
5581 and then Is_Derived_Type (Typ)
5582 then
5583 return Find_Prim_Op (Typ, Nam);
5584 else
5585 return Find_Inherited_TSS (Typ, Nam);
5586 end if;
5587 end Find_Stream_Subprogram;
5588
ee6ba406 5589 -----------------------
5590 -- Get_Index_Subtype --
5591 -----------------------
5592
5593 function Get_Index_Subtype (N : Node_Id) return Node_Id is
5594 P_Type : Entity_Id := Etype (Prefix (N));
5595 Indx : Node_Id;
5596 J : Int;
5597
5598 begin
5599 if Is_Access_Type (P_Type) then
5600 P_Type := Designated_Type (P_Type);
5601 end if;
5602
5603 if No (Expressions (N)) then
5604 J := 1;
5605 else
5606 J := UI_To_Int (Expr_Value (First (Expressions (N))));
5607 end if;
5608
5609 Indx := First_Index (P_Type);
5610 while J > 1 loop
5611 Next_Index (Indx);
5612 J := J - 1;
5613 end loop;
5614
5615 return Etype (Indx);
5616 end Get_Index_Subtype;
5617
5245b786 5618 -------------------------------
5619 -- Get_Stream_Convert_Pragma --
5620 -------------------------------
5621
5622 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id is
5623 Typ : Entity_Id;
5624 N : Node_Id;
5625
5626 begin
5627 -- Note: we cannot use Get_Rep_Pragma here because of the peculiarity
5628 -- that a stream convert pragma for a tagged type is not inherited from
5629 -- its parent. Probably what is wrong here is that it is basically
5630 -- incorrect to consider a stream convert pragma to be a representation
5631 -- pragma at all ???
5632
5633 N := First_Rep_Item (Implementation_Base_Type (T));
5634 while Present (N) loop
4c06b9d2 5635 if Nkind (N) = N_Pragma
5636 and then Pragma_Name (N) = Name_Stream_Convert
5637 then
5245b786 5638 -- For tagged types this pragma is not inherited, so we
5639 -- must verify that it is defined for the given type and
5640 -- not an ancestor.
5641
5642 Typ :=
5643 Entity (Expression (First (Pragma_Argument_Associations (N))));
5644
5645 if not Is_Tagged_Type (T)
5646 or else T = Typ
5647 or else (Is_Private_Type (Typ) and then T = Full_View (Typ))
5648 then
5649 return N;
5650 end if;
5651 end if;
5652
5653 Next_Rep_Item (N);
5654 end loop;
5655
5656 return Empty;
5657 end Get_Stream_Convert_Pragma;
5658
ee6ba406 5659 ---------------------------------
5660 -- Is_Constrained_Packed_Array --
5661 ---------------------------------
5662
5663 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean is
5664 Arr : Entity_Id := Typ;
5665
5666 begin
5667 if Is_Access_Type (Arr) then
5668 Arr := Designated_Type (Arr);
5669 end if;
5670
5671 return Is_Array_Type (Arr)
5672 and then Is_Constrained (Arr)
5673 and then Present (Packed_Array_Type (Arr));
5674 end Is_Constrained_Packed_Array;
5675
99f2248e 5676 ----------------------------------------
5677 -- Is_Inline_Floating_Point_Attribute --
5678 ----------------------------------------
5679
5680 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean is
5681 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
5682
5683 begin
5684 if Nkind (Parent (N)) /= N_Type_Conversion
5685 or else not Is_Integer_Type (Etype (Parent (N)))
5686 then
5687 return False;
5688 end if;
5689
5690 -- Should also support 'Machine_Rounding and 'Unbiased_Rounding, but
5691 -- required back end support has not been implemented yet ???
5692
5693 return Id = Attribute_Truncation;
5694 end Is_Inline_Floating_Point_Attribute;
5695
ee6ba406 5696end Exp_Attr;
Mirror of https://gcc.gnu.org/git/gcc.git