* gcc.dg/store-motion-fgcse-sm.c (dg-final): Cleanup
[official-gcc.git] / gcc / ada / exp_strm.adb
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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- E X P _ S T R M --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2014, Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Einfo; use Einfo;
28 with Elists; use Elists;
29 with Exp_Util; use Exp_Util;
30 with Namet; use Namet;
31 with Nlists; use Nlists;
32 with Nmake; use Nmake;
33 with Rtsfind; use Rtsfind;
34 with Sem_Aux; use Sem_Aux;
35 with Sem_Util; use Sem_Util;
36 with Sinfo; use Sinfo;
37 with Snames; use Snames;
38 with Stand; use Stand;
39 with Tbuild; use Tbuild;
40 with Ttypes; use Ttypes;
41 with Uintp; use Uintp;
43 package body Exp_Strm is
45 -----------------------
46 -- Local Subprograms --
47 -----------------------
49 procedure Build_Array_Read_Write_Procedure
50 (Nod : Node_Id;
51 Typ : Entity_Id;
52 Decl : out Node_Id;
53 Pnam : Entity_Id;
54 Nam : Name_Id);
55 -- Common routine shared to build either an array Read procedure or an
56 -- array Write procedure, Nam is Name_Read or Name_Write to select which.
57 -- Pnam is the defining identifier for the constructed procedure. The
58 -- other parameters are as for Build_Array_Read_Procedure except that
59 -- the first parameter Nod supplies the Sloc to be used to generate code.
61 procedure Build_Record_Read_Write_Procedure
62 (Loc : Source_Ptr;
63 Typ : Entity_Id;
64 Decl : out Node_Id;
65 Pnam : Entity_Id;
66 Nam : Name_Id);
67 -- Common routine shared to build a record Read Write procedure, Nam
68 -- is Name_Read or Name_Write to select which. Pnam is the defining
69 -- identifier for the constructed procedure. The other parameters are
70 -- as for Build_Record_Read_Procedure.
72 procedure Build_Stream_Function
73 (Loc : Source_Ptr;
74 Typ : Entity_Id;
75 Decl : out Node_Id;
76 Fnam : Entity_Id;
77 Decls : List_Id;
78 Stms : List_Id);
79 -- Called to build an array or record stream function. The first three
80 -- arguments are the same as Build_Record_Or_Elementary_Input_Function.
81 -- Decls and Stms are the declarations and statements for the body and
82 -- The parameter Fnam is the name of the constructed function.
84 function Has_Stream_Standard_Rep (U_Type : Entity_Id) return Boolean;
85 -- This function is used to test the type U_Type, to determine if it has
86 -- a standard representation from a streaming point of view. Standard means
87 -- that it has a standard representation (e.g. no enumeration rep clause),
88 -- and the size of the root type is the same as the streaming size (which
89 -- is defined as value specified by a Stream_Size clause if present, or
90 -- the Esize of U_Type if not).
92 function Make_Stream_Subprogram_Name
93 (Loc : Source_Ptr;
94 Typ : Entity_Id;
95 Nam : TSS_Name_Type) return Entity_Id;
96 -- Return the entity that identifies the stream subprogram for type Typ
97 -- that is identified by the given Nam. This procedure deals with the
98 -- difference between tagged types (where a single subprogram associated
99 -- with the type is generated) and all other cases (where a subprogram
100 -- is generated at the point of the stream attribute reference). The
101 -- Loc parameter is used as the Sloc of the created entity.
103 function Stream_Base_Type (E : Entity_Id) return Entity_Id;
104 -- Stream attributes work on the basis of the base type except for the
105 -- array case. For the array case, we do not go to the base type, but
106 -- to the first subtype if it is constrained. This avoids problems with
107 -- incorrect conversions in the packed array case. Stream_Base_Type is
108 -- exactly this function (returns the base type, unless we have an array
109 -- type whose first subtype is constrained, in which case it returns the
110 -- first subtype).
112 --------------------------------
113 -- Build_Array_Input_Function --
114 --------------------------------
116 -- The function we build looks like
118 -- function typSI[_nnn] (S : access RST) return Typ is
119 -- L1 : constant Index_Type_1 := Index_Type_1'Input (S);
120 -- H1 : constant Index_Type_1 := Index_Type_1'Input (S);
121 -- L2 : constant Index_Type_2 := Index_Type_2'Input (S);
122 -- H2 : constant Index_Type_2 := Index_Type_2'Input (S);
123 -- ..
124 -- Ln : constant Index_Type_n := Index_Type_n'Input (S);
125 -- Hn : constant Index_Type_n := Index_Type_n'Input (S);
127 -- V : Typ'Base (L1 .. H1, L2 .. H2, ... Ln .. Hn)
129 -- begin
130 -- Typ'Read (S, V);
131 -- return V;
132 -- end typSI[_nnn]
134 -- Note: the suffix [_nnn] is present for untagged types, where we generate
135 -- a local subprogram at the point of the occurrence of the attribute
136 -- reference, so the name must be unique.
138 procedure Build_Array_Input_Function
139 (Loc : Source_Ptr;
140 Typ : Entity_Id;
141 Decl : out Node_Id;
142 Fnam : out Entity_Id)
144 Dim : constant Pos := Number_Dimensions (Typ);
145 Lnam : Name_Id;
146 Hnam : Name_Id;
147 Decls : List_Id;
148 Ranges : List_Id;
149 Stms : List_Id;
150 Rstmt : Node_Id;
151 Indx : Node_Id;
152 Odecl : Node_Id;
154 begin
155 Decls := New_List;
156 Ranges := New_List;
157 Indx := First_Index (Typ);
158 for J in 1 .. Dim loop
159 Lnam := New_External_Name ('L', J);
160 Hnam := New_External_Name ('H', J);
162 Append_To (Decls,
163 Make_Object_Declaration (Loc,
164 Defining_Identifier => Make_Defining_Identifier (Loc, Lnam),
165 Constant_Present => True,
166 Object_Definition => New_Occurrence_Of (Etype (Indx), Loc),
167 Expression =>
168 Make_Attribute_Reference (Loc,
169 Prefix =>
170 New_Occurrence_Of (Stream_Base_Type (Etype (Indx)), Loc),
171 Attribute_Name => Name_Input,
172 Expressions => New_List (Make_Identifier (Loc, Name_S)))));
174 Append_To (Decls,
175 Make_Object_Declaration (Loc,
176 Defining_Identifier => Make_Defining_Identifier (Loc, Hnam),
177 Constant_Present => True,
178 Object_Definition =>
179 New_Occurrence_Of (Stream_Base_Type (Etype (Indx)), Loc),
180 Expression =>
181 Make_Attribute_Reference (Loc,
182 Prefix =>
183 New_Occurrence_Of (Stream_Base_Type (Etype (Indx)), Loc),
184 Attribute_Name => Name_Input,
185 Expressions => New_List (Make_Identifier (Loc, Name_S)))));
187 Append_To (Ranges,
188 Make_Range (Loc,
189 Low_Bound => Make_Identifier (Loc, Lnam),
190 High_Bound => Make_Identifier (Loc, Hnam)));
192 Next_Index (Indx);
193 end loop;
195 -- If the type is constrained, use it directly. Otherwise build a
196 -- subtype indication with the proper bounds.
198 if Is_Constrained (Typ) then
199 Odecl :=
200 Make_Object_Declaration (Loc,
201 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
202 Object_Definition => New_Occurrence_Of (Typ, Loc));
204 else
205 Odecl :=
206 Make_Object_Declaration (Loc,
207 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
208 Object_Definition =>
209 Make_Subtype_Indication (Loc,
210 Subtype_Mark =>
211 New_Occurrence_Of (Stream_Base_Type (Typ), Loc),
212 Constraint =>
213 Make_Index_Or_Discriminant_Constraint (Loc, Ranges)));
214 end if;
216 Rstmt :=
217 Make_Attribute_Reference (Loc,
218 Prefix => New_Occurrence_Of (Typ, Loc),
219 Attribute_Name => Name_Read,
220 Expressions => New_List (
221 Make_Identifier (Loc, Name_S),
222 Make_Identifier (Loc, Name_V)));
224 Stms := New_List (
225 Make_Extended_Return_Statement (Loc,
226 Return_Object_Declarations => New_List (Odecl),
227 Handled_Statement_Sequence =>
228 Make_Handled_Sequence_Of_Statements (Loc, New_List (Rstmt))));
230 Fnam :=
231 Make_Defining_Identifier (Loc,
232 Chars => Make_TSS_Name_Local (Typ, TSS_Stream_Input));
234 Build_Stream_Function (Loc, Typ, Decl, Fnam, Decls, Stms);
235 end Build_Array_Input_Function;
237 ----------------------------------
238 -- Build_Array_Output_Procedure --
239 ----------------------------------
241 procedure Build_Array_Output_Procedure
242 (Loc : Source_Ptr;
243 Typ : Entity_Id;
244 Decl : out Node_Id;
245 Pnam : out Entity_Id)
247 Stms : List_Id;
248 Indx : Node_Id;
250 begin
251 -- Build series of statements to output bounds
253 Indx := First_Index (Typ);
254 Stms := New_List;
256 for J in 1 .. Number_Dimensions (Typ) loop
257 Append_To (Stms,
258 Make_Attribute_Reference (Loc,
259 Prefix =>
260 New_Occurrence_Of (Stream_Base_Type (Etype (Indx)), Loc),
261 Attribute_Name => Name_Write,
262 Expressions => New_List (
263 Make_Identifier (Loc, Name_S),
264 Make_Attribute_Reference (Loc,
265 Prefix => Make_Identifier (Loc, Name_V),
266 Attribute_Name => Name_First,
267 Expressions => New_List (
268 Make_Integer_Literal (Loc, J))))));
270 Append_To (Stms,
271 Make_Attribute_Reference (Loc,
272 Prefix =>
273 New_Occurrence_Of (Stream_Base_Type (Etype (Indx)), Loc),
274 Attribute_Name => Name_Write,
275 Expressions => New_List (
276 Make_Identifier (Loc, Name_S),
277 Make_Attribute_Reference (Loc,
278 Prefix => Make_Identifier (Loc, Name_V),
279 Attribute_Name => Name_Last,
280 Expressions => New_List (
281 Make_Integer_Literal (Loc, J))))));
283 Next_Index (Indx);
284 end loop;
286 -- Append Write attribute to write array elements
288 Append_To (Stms,
289 Make_Attribute_Reference (Loc,
290 Prefix => New_Occurrence_Of (Typ, Loc),
291 Attribute_Name => Name_Write,
292 Expressions => New_List (
293 Make_Identifier (Loc, Name_S),
294 Make_Identifier (Loc, Name_V))));
296 Pnam :=
297 Make_Defining_Identifier (Loc,
298 Chars => Make_TSS_Name_Local (Typ, TSS_Stream_Output));
300 Build_Stream_Procedure (Loc, Typ, Decl, Pnam, Stms, False);
301 end Build_Array_Output_Procedure;
303 --------------------------------
304 -- Build_Array_Read_Procedure --
305 --------------------------------
307 procedure Build_Array_Read_Procedure
308 (Nod : Node_Id;
309 Typ : Entity_Id;
310 Decl : out Node_Id;
311 Pnam : out Entity_Id)
313 Loc : constant Source_Ptr := Sloc (Nod);
315 begin
316 Pnam :=
317 Make_Defining_Identifier (Loc,
318 Chars => Make_TSS_Name_Local (Typ, TSS_Stream_Read));
319 Build_Array_Read_Write_Procedure (Nod, Typ, Decl, Pnam, Name_Read);
320 end Build_Array_Read_Procedure;
322 --------------------------------------
323 -- Build_Array_Read_Write_Procedure --
324 --------------------------------------
326 -- The form of the array read/write procedure is as follows:
328 -- procedure pnam (S : access RST, V : [out] Typ) is
329 -- begin
330 -- for L1 in V'Range (1) loop
331 -- for L2 in V'Range (2) loop
332 -- ...
333 -- for Ln in V'Range (n) loop
334 -- Component_Type'Read/Write (S, V (L1, L2, .. Ln));
335 -- end loop;
336 -- ..
337 -- end loop;
338 -- end loop
339 -- end pnam;
341 -- The out keyword for V is supplied in the Read case
343 procedure Build_Array_Read_Write_Procedure
344 (Nod : Node_Id;
345 Typ : Entity_Id;
346 Decl : out Node_Id;
347 Pnam : Entity_Id;
348 Nam : Name_Id)
350 Loc : constant Source_Ptr := Sloc (Nod);
351 Ndim : constant Pos := Number_Dimensions (Typ);
352 Ctyp : constant Entity_Id := Component_Type (Typ);
354 Stm : Node_Id;
355 Exl : List_Id;
356 RW : Entity_Id;
358 begin
359 -- First build the inner attribute call
361 Exl := New_List;
363 for J in 1 .. Ndim loop
364 Append_To (Exl, Make_Identifier (Loc, New_External_Name ('L', J)));
365 end loop;
367 Stm :=
368 Make_Attribute_Reference (Loc,
369 Prefix => New_Occurrence_Of (Stream_Base_Type (Ctyp), Loc),
370 Attribute_Name => Nam,
371 Expressions => New_List (
372 Make_Identifier (Loc, Name_S),
373 Make_Indexed_Component (Loc,
374 Prefix => Make_Identifier (Loc, Name_V),
375 Expressions => Exl)));
377 -- The corresponding stream attribute for the component type of the
378 -- array may be user-defined, and be frozen after the type for which
379 -- we are generating the stream subprogram. In that case, freeze the
380 -- stream attribute of the component type, whose declaration could not
381 -- generate any additional freezing actions in any case.
383 if Nam = Name_Read then
384 RW := TSS (Base_Type (Ctyp), TSS_Stream_Read);
385 else
386 RW := TSS (Base_Type (Ctyp), TSS_Stream_Write);
387 end if;
389 if Present (RW)
390 and then not Is_Frozen (RW)
391 then
392 Set_Is_Frozen (RW);
393 end if;
395 -- Now this is the big loop to wrap that statement up in a sequence
396 -- of loops. The first time around, Stm is the attribute call. The
397 -- second and subsequent times, Stm is an inner loop.
399 for J in 1 .. Ndim loop
400 Stm :=
401 Make_Implicit_Loop_Statement (Nod,
402 Iteration_Scheme =>
403 Make_Iteration_Scheme (Loc,
404 Loop_Parameter_Specification =>
405 Make_Loop_Parameter_Specification (Loc,
406 Defining_Identifier =>
407 Make_Defining_Identifier (Loc,
408 Chars => New_External_Name ('L', Ndim - J + 1)),
410 Discrete_Subtype_Definition =>
411 Make_Attribute_Reference (Loc,
412 Prefix => Make_Identifier (Loc, Name_V),
413 Attribute_Name => Name_Range,
415 Expressions => New_List (
416 Make_Integer_Literal (Loc, Ndim - J + 1))))),
418 Statements => New_List (Stm));
420 end loop;
422 Build_Stream_Procedure
423 (Loc, Typ, Decl, Pnam, New_List (Stm), Nam = Name_Read);
424 end Build_Array_Read_Write_Procedure;
426 ---------------------------------
427 -- Build_Array_Write_Procedure --
428 ---------------------------------
430 procedure Build_Array_Write_Procedure
431 (Nod : Node_Id;
432 Typ : Entity_Id;
433 Decl : out Node_Id;
434 Pnam : out Entity_Id)
436 Loc : constant Source_Ptr := Sloc (Nod);
437 begin
438 Pnam :=
439 Make_Defining_Identifier (Loc,
440 Chars => Make_TSS_Name_Local (Typ, TSS_Stream_Write));
441 Build_Array_Read_Write_Procedure (Nod, Typ, Decl, Pnam, Name_Write);
442 end Build_Array_Write_Procedure;
444 ---------------------------------
445 -- Build_Elementary_Input_Call --
446 ---------------------------------
448 function Build_Elementary_Input_Call (N : Node_Id) return Node_Id is
449 Loc : constant Source_Ptr := Sloc (N);
450 P_Type : constant Entity_Id := Entity (Prefix (N));
451 U_Type : constant Entity_Id := Underlying_Type (P_Type);
452 Rt_Type : constant Entity_Id := Root_Type (U_Type);
453 FST : constant Entity_Id := First_Subtype (U_Type);
454 Strm : constant Node_Id := First (Expressions (N));
455 Targ : constant Node_Id := Next (Strm);
456 P_Size : constant Uint := Get_Stream_Size (FST);
457 Res : Node_Id;
458 Lib_RE : RE_Id;
460 begin
462 -- Check first for Boolean and Character. These are enumeration types,
463 -- but we treat them specially, since they may require special handling
464 -- in the transfer protocol. However, this special handling only applies
465 -- if they have standard representation, otherwise they are treated like
466 -- any other enumeration type.
468 if Rt_Type = Standard_Boolean
469 and then Has_Stream_Standard_Rep (U_Type)
470 then
471 Lib_RE := RE_I_B;
473 elsif Rt_Type = Standard_Character
474 and then Has_Stream_Standard_Rep (U_Type)
475 then
476 Lib_RE := RE_I_C;
478 elsif Rt_Type = Standard_Wide_Character
479 and then Has_Stream_Standard_Rep (U_Type)
480 then
481 Lib_RE := RE_I_WC;
483 elsif Rt_Type = Standard_Wide_Wide_Character
484 and then Has_Stream_Standard_Rep (U_Type)
485 then
486 Lib_RE := RE_I_WWC;
488 -- Floating point types
490 elsif Is_Floating_Point_Type (U_Type) then
492 -- Question: should we use P_Size or Rt_Type to distinguish between
493 -- possible floating point types? If a non-standard size or a stream
494 -- size is specified, then we should certainly use the size. But if
495 -- we have two types the same (notably Short_Float_Size = Float_Size
496 -- which is close to universally true, and Long_Long_Float_Size =
497 -- Long_Float_Size, true on most targets except the x86), then we
498 -- would really rather use the root type, so that if people want to
499 -- fiddle with System.Stream_Attributes to get inter-target portable
500 -- streams, they get the size they expect. Consider in particular the
501 -- case of a stream written on an x86, with 96-bit Long_Long_Float
502 -- being read into a non-x86 target with 64 bit Long_Long_Float. A
503 -- special version of System.Stream_Attributes can deal with this
504 -- provided the proper type is always used.
506 -- To deal with these two requirements we add the special checks
507 -- on equal sizes and use the root type to distinguish.
509 if P_Size <= Standard_Short_Float_Size
510 and then (Standard_Short_Float_Size /= Standard_Float_Size
511 or else Rt_Type = Standard_Short_Float)
512 then
513 Lib_RE := RE_I_SF;
515 elsif P_Size <= Standard_Float_Size then
516 Lib_RE := RE_I_F;
518 elsif P_Size <= Standard_Long_Float_Size
519 and then (Standard_Long_Float_Size /= Standard_Long_Long_Float_Size
520 or else Rt_Type = Standard_Long_Float)
521 then
522 Lib_RE := RE_I_LF;
524 else
525 Lib_RE := RE_I_LLF;
526 end if;
528 -- Signed integer types. Also includes signed fixed-point types and
529 -- enumeration types with a signed representation.
531 -- Note on signed integer types. We do not consider types as signed for
532 -- this purpose if they have no negative numbers, or if they have biased
533 -- representation. The reason is that the value in either case basically
534 -- represents an unsigned value.
536 -- For example, consider:
538 -- type W is range 0 .. 2**32 - 1;
539 -- for W'Size use 32;
541 -- This is a signed type, but the representation is unsigned, and may
542 -- be outside the range of a 32-bit signed integer, so this must be
543 -- treated as 32-bit unsigned.
545 -- Similarly, if we have
547 -- type W is range -1 .. +254;
548 -- for W'Size use 8;
550 -- then the representation is unsigned
552 elsif not Is_Unsigned_Type (FST)
554 -- The following set of tests gets repeated many times, we should
555 -- have an abstraction defined ???
557 and then
558 (Is_Fixed_Point_Type (U_Type)
559 or else
560 Is_Enumeration_Type (U_Type)
561 or else
562 (Is_Signed_Integer_Type (U_Type)
563 and then not Has_Biased_Representation (FST)))
565 then
566 if P_Size <= Standard_Short_Short_Integer_Size then
567 Lib_RE := RE_I_SSI;
569 elsif P_Size <= Standard_Short_Integer_Size then
570 Lib_RE := RE_I_SI;
572 elsif P_Size <= Standard_Integer_Size then
573 Lib_RE := RE_I_I;
575 elsif P_Size <= Standard_Long_Integer_Size then
576 Lib_RE := RE_I_LI;
578 else
579 Lib_RE := RE_I_LLI;
580 end if;
582 -- Unsigned integer types, also includes unsigned fixed-point types
583 -- and enumeration types with an unsigned representation (note that
584 -- we know they are unsigned because we already tested for signed).
586 -- Also includes signed integer types that are unsigned in the sense
587 -- that they do not include negative numbers. See above for details.
589 elsif Is_Modular_Integer_Type (U_Type)
590 or else Is_Fixed_Point_Type (U_Type)
591 or else Is_Enumeration_Type (U_Type)
592 or else Is_Signed_Integer_Type (U_Type)
593 then
594 if P_Size <= Standard_Short_Short_Integer_Size then
595 Lib_RE := RE_I_SSU;
597 elsif P_Size <= Standard_Short_Integer_Size then
598 Lib_RE := RE_I_SU;
600 elsif P_Size <= Standard_Integer_Size then
601 Lib_RE := RE_I_U;
603 elsif P_Size <= Standard_Long_Integer_Size then
604 Lib_RE := RE_I_LU;
606 else
607 Lib_RE := RE_I_LLU;
608 end if;
610 else pragma Assert (Is_Access_Type (U_Type));
611 if P_Size > System_Address_Size then
612 Lib_RE := RE_I_AD;
613 else
614 Lib_RE := RE_I_AS;
615 end if;
616 end if;
618 -- Call the function, and do an unchecked conversion of the result
619 -- to the actual type of the prefix. If the target is a discriminant,
620 -- and we are in the body of the default implementation of a 'Read
621 -- attribute, set target type to force a constraint check (13.13.2(35)).
622 -- If the type of the discriminant is currently private, add another
623 -- unchecked conversion from the full view.
625 if Nkind (Targ) = N_Identifier
626 and then Is_Internal_Name (Chars (Targ))
627 and then Is_TSS (Scope (Entity (Targ)), TSS_Stream_Read)
628 then
629 Res :=
630 Unchecked_Convert_To (Base_Type (U_Type),
631 Make_Function_Call (Loc,
632 Name => New_Occurrence_Of (RTE (Lib_RE), Loc),
633 Parameter_Associations => New_List (
634 Relocate_Node (Strm))));
636 Set_Do_Range_Check (Res);
638 if Base_Type (P_Type) /= Base_Type (U_Type) then
639 Res := Unchecked_Convert_To (Base_Type (P_Type), Res);
640 end if;
642 return Res;
644 else
645 return
646 Unchecked_Convert_To (P_Type,
647 Make_Function_Call (Loc,
648 Name => New_Occurrence_Of (RTE (Lib_RE), Loc),
649 Parameter_Associations => New_List (
650 Relocate_Node (Strm))));
651 end if;
652 end Build_Elementary_Input_Call;
654 ---------------------------------
655 -- Build_Elementary_Write_Call --
656 ---------------------------------
658 function Build_Elementary_Write_Call (N : Node_Id) return Node_Id is
659 Loc : constant Source_Ptr := Sloc (N);
660 P_Type : constant Entity_Id := Entity (Prefix (N));
661 U_Type : constant Entity_Id := Underlying_Type (P_Type);
662 Rt_Type : constant Entity_Id := Root_Type (U_Type);
663 FST : constant Entity_Id := First_Subtype (U_Type);
664 Strm : constant Node_Id := First (Expressions (N));
665 Item : constant Node_Id := Next (Strm);
666 P_Size : Uint;
667 Lib_RE : RE_Id;
668 Libent : Entity_Id;
670 begin
672 -- Compute the size of the stream element. This is either the size of
673 -- the first subtype or if given the size of the Stream_Size attribute.
675 if Has_Stream_Size_Clause (FST) then
676 P_Size := Static_Integer (Expression (Stream_Size_Clause (FST)));
677 else
678 P_Size := Esize (FST);
679 end if;
681 -- Find the routine to be called
683 -- Check for First Boolean and Character. These are enumeration types,
684 -- but we treat them specially, since they may require special handling
685 -- in the transfer protocol. However, this special handling only applies
686 -- if they have standard representation, otherwise they are treated like
687 -- any other enumeration type.
689 if Rt_Type = Standard_Boolean
690 and then Has_Stream_Standard_Rep (U_Type)
691 then
692 Lib_RE := RE_W_B;
694 elsif Rt_Type = Standard_Character
695 and then Has_Stream_Standard_Rep (U_Type)
696 then
697 Lib_RE := RE_W_C;
699 elsif Rt_Type = Standard_Wide_Character
700 and then Has_Stream_Standard_Rep (U_Type)
701 then
702 Lib_RE := RE_W_WC;
704 elsif Rt_Type = Standard_Wide_Wide_Character
705 and then Has_Stream_Standard_Rep (U_Type)
706 then
707 Lib_RE := RE_W_WWC;
709 -- Floating point types
711 elsif Is_Floating_Point_Type (U_Type) then
713 -- Question: should we use P_Size or Rt_Type to distinguish between
714 -- possible floating point types? If a non-standard size or a stream
715 -- size is specified, then we should certainly use the size. But if
716 -- we have two types the same (notably Short_Float_Size = Float_Size
717 -- which is close to universally true, and Long_Long_Float_Size =
718 -- Long_Float_Size, true on most targets except the x86), then we
719 -- would really rather use the root type, so that if people want to
720 -- fiddle with System.Stream_Attributes to get inter-target portable
721 -- streams, they get the size they expect. Consider in particular the
722 -- case of a stream written on an x86, with 96-bit Long_Long_Float
723 -- being read into a non-x86 target with 64 bit Long_Long_Float. A
724 -- special version of System.Stream_Attributes can deal with this
725 -- provided the proper type is always used.
727 -- To deal with these two requirements we add the special checks
728 -- on equal sizes and use the root type to distinguish.
730 if P_Size <= Standard_Short_Float_Size
731 and then (Standard_Short_Float_Size /= Standard_Float_Size
732 or else Rt_Type = Standard_Short_Float)
733 then
734 Lib_RE := RE_W_SF;
736 elsif P_Size <= Standard_Float_Size then
737 Lib_RE := RE_W_F;
739 elsif P_Size <= Standard_Long_Float_Size
740 and then (Standard_Long_Float_Size /= Standard_Long_Long_Float_Size
741 or else Rt_Type = Standard_Long_Float)
742 then
743 Lib_RE := RE_W_LF;
745 else
746 Lib_RE := RE_W_LLF;
747 end if;
749 -- Signed integer types. Also includes signed fixed-point types and
750 -- signed enumeration types share this circuitry.
752 -- Note on signed integer types. We do not consider types as signed for
753 -- this purpose if they have no negative numbers, or if they have biased
754 -- representation. The reason is that the value in either case basically
755 -- represents an unsigned value.
757 -- For example, consider:
759 -- type W is range 0 .. 2**32 - 1;
760 -- for W'Size use 32;
762 -- This is a signed type, but the representation is unsigned, and may
763 -- be outside the range of a 32-bit signed integer, so this must be
764 -- treated as 32-bit unsigned.
766 -- Similarly, the representation is also unsigned if we have:
768 -- type W is range -1 .. +254;
769 -- for W'Size use 8;
771 -- forcing a biased and unsigned representation
773 elsif not Is_Unsigned_Type (FST)
774 and then
775 (Is_Fixed_Point_Type (U_Type)
776 or else
777 Is_Enumeration_Type (U_Type)
778 or else
779 (Is_Signed_Integer_Type (U_Type)
780 and then not Has_Biased_Representation (FST)))
781 then
782 if P_Size <= Standard_Short_Short_Integer_Size then
783 Lib_RE := RE_W_SSI;
784 elsif P_Size <= Standard_Short_Integer_Size then
785 Lib_RE := RE_W_SI;
786 elsif P_Size <= Standard_Integer_Size then
787 Lib_RE := RE_W_I;
788 elsif P_Size <= Standard_Long_Integer_Size then
789 Lib_RE := RE_W_LI;
790 else
791 Lib_RE := RE_W_LLI;
792 end if;
794 -- Unsigned integer types, also includes unsigned fixed-point types
795 -- and unsigned enumeration types (note we know they are unsigned
796 -- because we already tested for signed above).
798 -- Also includes signed integer types that are unsigned in the sense
799 -- that they do not include negative numbers. See above for details.
801 elsif Is_Modular_Integer_Type (U_Type)
802 or else Is_Fixed_Point_Type (U_Type)
803 or else Is_Enumeration_Type (U_Type)
804 or else Is_Signed_Integer_Type (U_Type)
805 then
806 if P_Size <= Standard_Short_Short_Integer_Size then
807 Lib_RE := RE_W_SSU;
808 elsif P_Size <= Standard_Short_Integer_Size then
809 Lib_RE := RE_W_SU;
810 elsif P_Size <= Standard_Integer_Size then
811 Lib_RE := RE_W_U;
812 elsif P_Size <= Standard_Long_Integer_Size then
813 Lib_RE := RE_W_LU;
814 else
815 Lib_RE := RE_W_LLU;
816 end if;
818 else pragma Assert (Is_Access_Type (U_Type));
820 if P_Size > System_Address_Size then
821 Lib_RE := RE_W_AD;
822 else
823 Lib_RE := RE_W_AS;
824 end if;
825 end if;
827 -- Unchecked-convert parameter to the required type (i.e. the type of
828 -- the corresponding parameter, and call the appropriate routine.
830 Libent := RTE (Lib_RE);
832 return
833 Make_Procedure_Call_Statement (Loc,
834 Name => New_Occurrence_Of (Libent, Loc),
835 Parameter_Associations => New_List (
836 Relocate_Node (Strm),
837 Unchecked_Convert_To (Etype (Next_Formal (First_Formal (Libent))),
838 Relocate_Node (Item))));
839 end Build_Elementary_Write_Call;
841 -----------------------------------------
842 -- Build_Mutable_Record_Read_Procedure --
843 -----------------------------------------
845 procedure Build_Mutable_Record_Read_Procedure
846 (Loc : Source_Ptr;
847 Typ : Entity_Id;
848 Decl : out Node_Id;
849 Pnam : out Entity_Id)
851 Out_Formal : Node_Id;
852 -- Expression denoting the out formal parameter
854 Dcls : constant List_Id := New_List;
855 -- Declarations for the 'Read body
857 Stms : constant List_Id := New_List;
858 -- Statements for the 'Read body
860 Disc : Entity_Id;
861 -- Entity of the discriminant being processed
863 Tmp_For_Disc : Entity_Id;
864 -- Temporary object used to read the value of Disc
866 Tmps_For_Discs : constant List_Id := New_List;
867 -- List of object declarations for temporaries holding the read values
868 -- for the discriminants.
870 Cstr : constant List_Id := New_List;
871 -- List of constraints to be applied on temporary record
873 Discriminant_Checks : constant List_Id := New_List;
874 -- List of discriminant checks to be performed if the actual object
875 -- is constrained.
877 Tmp : constant Entity_Id := Make_Defining_Identifier (Loc, Name_V);
878 -- Temporary record must hide formal (assignments to components of the
879 -- record are always generated with V as the identifier for the record).
881 Constrained_Stms : List_Id := New_List;
882 -- Statements within the block where we have the constrained temporary
884 begin
885 -- A mutable type cannot be a tagged type, so we generate a new name
886 -- for the stream procedure.
888 Pnam :=
889 Make_Defining_Identifier (Loc,
890 Chars => Make_TSS_Name_Local (Typ, TSS_Stream_Read));
892 if Is_Unchecked_Union (Typ) then
894 -- If this is an unchecked union, the stream procedure is erroneous,
895 -- because there are no discriminants to read.
897 -- This should generate a warning ???
899 Append_To (Stms,
900 Make_Raise_Program_Error (Loc,
901 Reason => PE_Unchecked_Union_Restriction));
903 Build_Stream_Procedure (Loc, Typ, Decl, Pnam, Stms, Outp => True);
904 return;
905 end if;
907 Disc := First_Discriminant (Typ);
909 Out_Formal :=
910 Make_Selected_Component (Loc,
911 Prefix => New_Occurrence_Of (Pnam, Loc),
912 Selector_Name => Make_Identifier (Loc, Name_V));
914 -- Generate Reads for the discriminants of the type. The discriminants
915 -- need to be read before the rest of the components, so that variants
916 -- are initialized correctly. The discriminants must be read into temp
917 -- variables so an incomplete Read (interrupted by an exception, for
918 -- example) does not alter the passed object.
920 while Present (Disc) loop
921 Tmp_For_Disc := Make_Defining_Identifier (Loc,
922 New_External_Name (Chars (Disc), "D"));
924 Append_To (Tmps_For_Discs,
925 Make_Object_Declaration (Loc,
926 Defining_Identifier => Tmp_For_Disc,
927 Object_Definition => New_Occurrence_Of (Etype (Disc), Loc)));
928 Set_No_Initialization (Last (Tmps_For_Discs));
930 Append_To (Stms,
931 Make_Attribute_Reference (Loc,
932 Prefix => New_Occurrence_Of (Etype (Disc), Loc),
933 Attribute_Name => Name_Read,
934 Expressions => New_List (
935 Make_Identifier (Loc, Name_S),
936 New_Occurrence_Of (Tmp_For_Disc, Loc))));
938 Append_To (Cstr,
939 Make_Discriminant_Association (Loc,
940 Selector_Names => New_List (New_Occurrence_Of (Disc, Loc)),
941 Expression => New_Occurrence_Of (Tmp_For_Disc, Loc)));
943 Append_To (Discriminant_Checks,
944 Make_Raise_Constraint_Error (Loc,
945 Condition =>
946 Make_Op_Ne (Loc,
947 Left_Opnd => New_Occurrence_Of (Tmp_For_Disc, Loc),
948 Right_Opnd =>
949 Make_Selected_Component (Loc,
950 Prefix => New_Copy_Tree (Out_Formal),
951 Selector_Name => New_Occurrence_Of (Disc, Loc))),
952 Reason => CE_Discriminant_Check_Failed));
953 Next_Discriminant (Disc);
954 end loop;
956 -- Generate reads for the components of the record (including those
957 -- that depend on discriminants).
959 Build_Record_Read_Write_Procedure (Loc, Typ, Decl, Pnam, Name_Read);
961 -- Save original statement sequence for component assignments, and
962 -- replace it with Stms.
964 Constrained_Stms := Statements (Handled_Statement_Sequence (Decl));
965 Set_Handled_Statement_Sequence (Decl,
966 Make_Handled_Sequence_Of_Statements (Loc,
967 Statements => Stms));
969 -- If Typ has controlled components (i.e. if it is classwide or
970 -- Has_Controlled), or components constrained using the discriminants
971 -- of Typ, then we need to ensure that all component assignments are
972 -- performed on an object that has been appropriately constrained
973 -- prior to being initialized. To this effect, we wrap the component
974 -- assignments in a block where V is a constrained temporary.
976 Append_To (Dcls,
977 Make_Object_Declaration (Loc,
978 Defining_Identifier => Tmp,
979 Object_Definition =>
980 Make_Subtype_Indication (Loc,
981 Subtype_Mark => New_Occurrence_Of (Base_Type (Typ), Loc),
982 Constraint =>
983 Make_Index_Or_Discriminant_Constraint (Loc,
984 Constraints => Cstr))));
986 -- AI05-023-1: Insert discriminant check prior to initialization of the
987 -- constrained temporary.
989 Append_To (Stms,
990 Make_Implicit_If_Statement (Pnam,
991 Condition =>
992 Make_Attribute_Reference (Loc,
993 Prefix => New_Copy_Tree (Out_Formal),
994 Attribute_Name => Name_Constrained),
995 Then_Statements => Discriminant_Checks));
997 -- Now insert back original component assignments, wrapped in a block
998 -- in which V is the constrained temporary.
1000 Append_To (Stms,
1001 Make_Block_Statement (Loc,
1002 Declarations => Dcls,
1003 Handled_Statement_Sequence => Parent (Constrained_Stms)));
1005 Append_To (Constrained_Stms,
1006 Make_Assignment_Statement (Loc,
1007 Name => Out_Formal,
1008 Expression => Make_Identifier (Loc, Name_V)));
1010 Set_Declarations (Decl, Tmps_For_Discs);
1011 end Build_Mutable_Record_Read_Procedure;
1013 ------------------------------------------
1014 -- Build_Mutable_Record_Write_Procedure --
1015 ------------------------------------------
1017 procedure Build_Mutable_Record_Write_Procedure
1018 (Loc : Source_Ptr;
1019 Typ : Entity_Id;
1020 Decl : out Node_Id;
1021 Pnam : out Entity_Id)
1023 Stms : List_Id;
1024 Disc : Entity_Id;
1025 D_Ref : Node_Id;
1027 begin
1028 Stms := New_List;
1029 Disc := First_Discriminant (Typ);
1031 -- Generate Writes for the discriminants of the type
1032 -- If the type is an unchecked union, use the default values of
1033 -- the discriminants, because they are not stored.
1035 while Present (Disc) loop
1036 if Is_Unchecked_Union (Typ) then
1037 D_Ref :=
1038 New_Copy_Tree (Discriminant_Default_Value (Disc));
1039 else
1040 D_Ref :=
1041 Make_Selected_Component (Loc,
1042 Prefix => Make_Identifier (Loc, Name_V),
1043 Selector_Name => New_Occurrence_Of (Disc, Loc));
1044 end if;
1046 Append_To (Stms,
1047 Make_Attribute_Reference (Loc,
1048 Prefix => New_Occurrence_Of (Etype (Disc), Loc),
1049 Attribute_Name => Name_Write,
1050 Expressions => New_List (
1051 Make_Identifier (Loc, Name_S),
1052 D_Ref)));
1054 Next_Discriminant (Disc);
1055 end loop;
1057 -- A mutable type cannot be a tagged type, so we generate a new name
1058 -- for the stream procedure.
1060 Pnam :=
1061 Make_Defining_Identifier (Loc,
1062 Chars => Make_TSS_Name_Local (Typ, TSS_Stream_Write));
1063 Build_Record_Read_Write_Procedure (Loc, Typ, Decl, Pnam, Name_Write);
1065 -- Write the discriminants before the rest of the components, so
1066 -- that discriminant values are properly set of variants, etc.
1068 if Is_Non_Empty_List (
1069 Statements (Handled_Statement_Sequence (Decl)))
1070 then
1071 Insert_List_Before
1072 (First (Statements (Handled_Statement_Sequence (Decl))), Stms);
1073 else
1074 Set_Statements (Handled_Statement_Sequence (Decl), Stms);
1075 end if;
1076 end Build_Mutable_Record_Write_Procedure;
1078 -----------------------------------------------
1079 -- Build_Record_Or_Elementary_Input_Function --
1080 -----------------------------------------------
1082 -- The function we build looks like
1084 -- function InputN (S : access RST) return Typ is
1085 -- C1 : constant Disc_Type_1;
1086 -- Discr_Type_1'Read (S, C1);
1087 -- C2 : constant Disc_Type_2;
1088 -- Discr_Type_2'Read (S, C2);
1089 -- ...
1090 -- Cn : constant Disc_Type_n;
1091 -- Discr_Type_n'Read (S, Cn);
1092 -- V : Typ (C1, C2, .. Cn)
1094 -- begin
1095 -- Typ'Read (S, V);
1096 -- return V;
1097 -- end InputN
1099 -- The discriminants are of course only present in the case of a record
1100 -- with discriminants. In the case of a record with no discriminants, or
1101 -- an elementary type, then no Cn constants are defined.
1103 procedure Build_Record_Or_Elementary_Input_Function
1104 (Loc : Source_Ptr;
1105 Typ : Entity_Id;
1106 Decl : out Node_Id;
1107 Fnam : out Entity_Id)
1109 B_Typ : constant Entity_Id := Base_Type (Typ);
1110 Cn : Name_Id;
1111 Constr : List_Id;
1112 Decls : List_Id;
1113 Discr : Entity_Id;
1114 Discr_Elmt : Elmt_Id := No_Elmt;
1115 J : Pos;
1116 Obj_Decl : Node_Id;
1117 Odef : Node_Id;
1118 Stms : List_Id;
1120 begin
1121 Decls := New_List;
1122 Constr := New_List;
1124 J := 1;
1126 -- In the presence of multiple instantiations (as in uses of the Booch
1127 -- components) the base type may be private, and the underlying type
1128 -- already constrained, in which case there's no discriminant constraint
1129 -- to construct.
1131 if Has_Discriminants (Typ)
1132 and then No (Discriminant_Default_Value (First_Discriminant (Typ)))
1133 and then not Is_Constrained (Underlying_Type (B_Typ))
1134 then
1135 Discr := First_Discriminant (B_Typ);
1137 -- If the prefix subtype is constrained, then retrieve the first
1138 -- element of its constraint.
1140 if Is_Constrained (Typ) then
1141 Discr_Elmt := First_Elmt (Discriminant_Constraint (Typ));
1142 end if;
1144 while Present (Discr) loop
1145 Cn := New_External_Name ('C', J);
1147 Decl :=
1148 Make_Object_Declaration (Loc,
1149 Defining_Identifier => Make_Defining_Identifier (Loc, Cn),
1150 Object_Definition =>
1151 New_Occurrence_Of (Etype (Discr), Loc));
1153 -- If this is an access discriminant, do not perform default
1154 -- initialization. The discriminant is about to get its value
1155 -- from Read, and if the type is null excluding we do not want
1156 -- spurious warnings on an initial null value.
1158 if Is_Access_Type (Etype (Discr)) then
1159 Set_No_Initialization (Decl);
1160 end if;
1162 Append_To (Decls, Decl);
1163 Append_To (Decls,
1164 Make_Attribute_Reference (Loc,
1165 Prefix => New_Occurrence_Of (Etype (Discr), Loc),
1166 Attribute_Name => Name_Read,
1167 Expressions => New_List (
1168 Make_Identifier (Loc, Name_S),
1169 Make_Identifier (Loc, Cn))));
1171 Append_To (Constr, Make_Identifier (Loc, Cn));
1173 -- If the prefix subtype imposes a discriminant constraint, then
1174 -- check that each discriminant value equals the value read.
1176 if Present (Discr_Elmt) then
1177 Append_To (Decls,
1178 Make_Raise_Constraint_Error (Loc,
1179 Condition => Make_Op_Ne (Loc,
1180 Left_Opnd =>
1181 New_Occurrence_Of
1182 (Defining_Identifier (Decl), Loc),
1183 Right_Opnd =>
1184 New_Copy_Tree (Node (Discr_Elmt))),
1185 Reason => CE_Discriminant_Check_Failed));
1187 Next_Elmt (Discr_Elmt);
1188 end if;
1190 Next_Discriminant (Discr);
1191 J := J + 1;
1192 end loop;
1194 Odef :=
1195 Make_Subtype_Indication (Loc,
1196 Subtype_Mark => New_Occurrence_Of (B_Typ, Loc),
1197 Constraint =>
1198 Make_Index_Or_Discriminant_Constraint (Loc,
1199 Constraints => Constr));
1201 -- If no discriminants, then just use the type with no constraint
1203 else
1204 Odef := New_Occurrence_Of (B_Typ, Loc);
1205 end if;
1207 -- Create an extended return statement encapsulating the result object
1208 -- and 'Read call, which is needed in general for proper handling of
1209 -- build-in-place results (such as when the result type is inherently
1210 -- limited).
1212 Obj_Decl :=
1213 Make_Object_Declaration (Loc,
1214 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
1215 Object_Definition => Odef);
1217 -- If the type is an access type, do not perform default initialization.
1218 -- The object is about to get its value from Read, and if the type is
1219 -- null excluding we do not want spurious warnings on an initial null.
1221 if Is_Access_Type (B_Typ) then
1222 Set_No_Initialization (Obj_Decl);
1223 end if;
1225 Stms := New_List (
1226 Make_Extended_Return_Statement (Loc,
1227 Return_Object_Declarations => New_List (Obj_Decl),
1228 Handled_Statement_Sequence =>
1229 Make_Handled_Sequence_Of_Statements (Loc,
1230 Statements => New_List (
1231 Make_Attribute_Reference (Loc,
1232 Prefix => New_Occurrence_Of (B_Typ, Loc),
1233 Attribute_Name => Name_Read,
1234 Expressions => New_List (
1235 Make_Identifier (Loc, Name_S),
1236 Make_Identifier (Loc, Name_V)))))));
1238 Fnam := Make_Stream_Subprogram_Name (Loc, B_Typ, TSS_Stream_Input);
1240 Build_Stream_Function (Loc, B_Typ, Decl, Fnam, Decls, Stms);
1241 end Build_Record_Or_Elementary_Input_Function;
1243 -------------------------------------------------
1244 -- Build_Record_Or_Elementary_Output_Procedure --
1245 -------------------------------------------------
1247 procedure Build_Record_Or_Elementary_Output_Procedure
1248 (Loc : Source_Ptr;
1249 Typ : Entity_Id;
1250 Decl : out Node_Id;
1251 Pnam : out Entity_Id)
1253 Stms : List_Id;
1254 Disc : Entity_Id;
1255 Disc_Ref : Node_Id;
1257 begin
1258 Stms := New_List;
1260 -- Note that of course there will be no discriminants for the elementary
1261 -- type case, so Has_Discriminants will be False. Note that the language
1262 -- rules do not allow writing the discriminants in the defaulted case,
1263 -- because those are written by 'Write.
1265 if Has_Discriminants (Typ)
1266 and then No (Discriminant_Default_Value (First_Discriminant (Typ)))
1267 then
1268 Disc := First_Discriminant (Typ);
1269 while Present (Disc) loop
1271 -- If the type is an unchecked union, it must have default
1272 -- discriminants (this is checked earlier), and those defaults
1273 -- are written out to the stream.
1275 if Is_Unchecked_Union (Typ) then
1276 Disc_Ref := New_Copy_Tree (Discriminant_Default_Value (Disc));
1278 else
1279 Disc_Ref :=
1280 Make_Selected_Component (Loc,
1281 Prefix => Make_Identifier (Loc, Name_V),
1282 Selector_Name => New_Occurrence_Of (Disc, Loc));
1283 end if;
1285 Append_To (Stms,
1286 Make_Attribute_Reference (Loc,
1287 Prefix =>
1288 New_Occurrence_Of (Stream_Base_Type (Etype (Disc)), Loc),
1289 Attribute_Name => Name_Write,
1290 Expressions => New_List (
1291 Make_Identifier (Loc, Name_S),
1292 Disc_Ref)));
1294 Next_Discriminant (Disc);
1295 end loop;
1296 end if;
1298 Append_To (Stms,
1299 Make_Attribute_Reference (Loc,
1300 Prefix => New_Occurrence_Of (Typ, Loc),
1301 Attribute_Name => Name_Write,
1302 Expressions => New_List (
1303 Make_Identifier (Loc, Name_S),
1304 Make_Identifier (Loc, Name_V))));
1306 Pnam := Make_Stream_Subprogram_Name (Loc, Typ, TSS_Stream_Output);
1308 Build_Stream_Procedure (Loc, Typ, Decl, Pnam, Stms, False);
1309 end Build_Record_Or_Elementary_Output_Procedure;
1311 ---------------------------------
1312 -- Build_Record_Read_Procedure --
1313 ---------------------------------
1315 procedure Build_Record_Read_Procedure
1316 (Loc : Source_Ptr;
1317 Typ : Entity_Id;
1318 Decl : out Node_Id;
1319 Pnam : out Entity_Id)
1321 begin
1322 Pnam := Make_Stream_Subprogram_Name (Loc, Typ, TSS_Stream_Read);
1323 Build_Record_Read_Write_Procedure (Loc, Typ, Decl, Pnam, Name_Read);
1324 end Build_Record_Read_Procedure;
1326 ---------------------------------------
1327 -- Build_Record_Read_Write_Procedure --
1328 ---------------------------------------
1330 -- The form of the record read/write procedure is as shown by the
1331 -- following example for a case with one discriminant case variant:
1333 -- procedure pnam (S : access RST, V : [out] Typ) is
1334 -- begin
1335 -- Component_Type'Read/Write (S, V.component);
1336 -- Component_Type'Read/Write (S, V.component);
1337 -- ...
1338 -- Component_Type'Read/Write (S, V.component);
1340 -- case V.discriminant is
1341 -- when choices =>
1342 -- Component_Type'Read/Write (S, V.component);
1343 -- Component_Type'Read/Write (S, V.component);
1344 -- ...
1345 -- Component_Type'Read/Write (S, V.component);
1347 -- when choices =>
1348 -- Component_Type'Read/Write (S, V.component);
1349 -- Component_Type'Read/Write (S, V.component);
1350 -- ...
1351 -- Component_Type'Read/Write (S, V.component);
1352 -- ...
1353 -- end case;
1354 -- end pnam;
1356 -- The out keyword for V is supplied in the Read case
1358 procedure Build_Record_Read_Write_Procedure
1359 (Loc : Source_Ptr;
1360 Typ : Entity_Id;
1361 Decl : out Node_Id;
1362 Pnam : Entity_Id;
1363 Nam : Name_Id)
1365 Rdef : Node_Id;
1366 Stms : List_Id;
1367 Typt : Entity_Id;
1369 In_Limited_Extension : Boolean := False;
1370 -- Set to True while processing the record extension definition
1371 -- for an extension of a limited type (for which an ancestor type
1372 -- has an explicit Nam attribute definition).
1374 function Make_Component_List_Attributes (CL : Node_Id) return List_Id;
1375 -- Returns a sequence of attributes to process the components that
1376 -- are referenced in the given component list.
1378 function Make_Field_Attribute (C : Entity_Id) return Node_Id;
1379 -- Given C, the entity for a discriminant or component, build
1380 -- an attribute for the corresponding field values.
1382 function Make_Field_Attributes (Clist : List_Id) return List_Id;
1383 -- Given Clist, a component items list, construct series of attributes
1384 -- for fieldwise processing of the corresponding components.
1386 ------------------------------------
1387 -- Make_Component_List_Attributes --
1388 ------------------------------------
1390 function Make_Component_List_Attributes (CL : Node_Id) return List_Id is
1391 CI : constant List_Id := Component_Items (CL);
1392 VP : constant Node_Id := Variant_Part (CL);
1394 Result : List_Id;
1395 Alts : List_Id;
1396 V : Node_Id;
1397 DC : Node_Id;
1398 DCH : List_Id;
1399 D_Ref : Node_Id;
1401 begin
1402 Result := Make_Field_Attributes (CI);
1404 if Present (VP) then
1405 Alts := New_List;
1407 V := First_Non_Pragma (Variants (VP));
1408 while Present (V) loop
1409 DCH := New_List;
1411 DC := First (Discrete_Choices (V));
1412 while Present (DC) loop
1413 Append_To (DCH, New_Copy_Tree (DC));
1414 Next (DC);
1415 end loop;
1417 Append_To (Alts,
1418 Make_Case_Statement_Alternative (Loc,
1419 Discrete_Choices => DCH,
1420 Statements =>
1421 Make_Component_List_Attributes (Component_List (V))));
1422 Next_Non_Pragma (V);
1423 end loop;
1425 -- Note: in the following, we make sure that we use new occurrence
1426 -- of for the selector, since there are cases in which we make a
1427 -- reference to a hidden discriminant that is not visible.
1429 -- If the enclosing record is an unchecked_union, we use the
1430 -- default expressions for the discriminant (it must exist)
1431 -- because we cannot generate a reference to it, given that
1432 -- it is not stored.
1434 if Is_Unchecked_Union (Scope (Entity (Name (VP)))) then
1435 D_Ref :=
1436 New_Copy_Tree
1437 (Discriminant_Default_Value (Entity (Name (VP))));
1438 else
1439 D_Ref :=
1440 Make_Selected_Component (Loc,
1441 Prefix => Make_Identifier (Loc, Name_V),
1442 Selector_Name =>
1443 New_Occurrence_Of (Entity (Name (VP)), Loc));
1444 end if;
1446 Append_To (Result,
1447 Make_Case_Statement (Loc,
1448 Expression => D_Ref,
1449 Alternatives => Alts));
1450 end if;
1452 return Result;
1453 end Make_Component_List_Attributes;
1455 --------------------------
1456 -- Make_Field_Attribute --
1457 --------------------------
1459 function Make_Field_Attribute (C : Entity_Id) return Node_Id is
1460 Field_Typ : constant Entity_Id := Stream_Base_Type (Etype (C));
1462 TSS_Names : constant array (Name_Input .. Name_Write) of
1463 TSS_Name_Type :=
1464 (Name_Read => TSS_Stream_Read,
1465 Name_Write => TSS_Stream_Write,
1466 Name_Input => TSS_Stream_Input,
1467 Name_Output => TSS_Stream_Output,
1468 others => TSS_Null);
1469 pragma Assert (TSS_Names (Nam) /= TSS_Null);
1471 begin
1472 if In_Limited_Extension
1473 and then Is_Limited_Type (Field_Typ)
1474 and then No (Find_Inherited_TSS (Field_Typ, TSS_Names (Nam)))
1475 then
1476 -- The declaration is illegal per 13.13.2(9/1), and this is
1477 -- enforced in Exp_Ch3.Check_Stream_Attributes. Keep the caller
1478 -- happy by returning a null statement.
1480 return Make_Null_Statement (Loc);
1481 end if;
1483 return
1484 Make_Attribute_Reference (Loc,
1485 Prefix => New_Occurrence_Of (Field_Typ, Loc),
1486 Attribute_Name => Nam,
1487 Expressions => New_List (
1488 Make_Identifier (Loc, Name_S),
1489 Make_Selected_Component (Loc,
1490 Prefix => Make_Identifier (Loc, Name_V),
1491 Selector_Name => New_Occurrence_Of (C, Loc))));
1492 end Make_Field_Attribute;
1494 ---------------------------
1495 -- Make_Field_Attributes --
1496 ---------------------------
1498 function Make_Field_Attributes (Clist : List_Id) return List_Id is
1499 Item : Node_Id;
1500 Result : List_Id;
1502 begin
1503 Result := New_List;
1505 if Present (Clist) then
1506 Item := First (Clist);
1508 -- Loop through components, skipping all internal components,
1509 -- which are not part of the value (e.g. _Tag), except that we
1510 -- don't skip the _Parent, since we do want to process that
1511 -- recursively. If _Parent is an interface type, being abstract
1512 -- with no components there is no need to handle it.
1514 while Present (Item) loop
1515 if Nkind (Item) = N_Component_Declaration
1516 and then
1517 ((Chars (Defining_Identifier (Item)) = Name_uParent
1518 and then not Is_Interface
1519 (Etype (Defining_Identifier (Item))))
1520 or else
1521 not Is_Internal_Name (Chars (Defining_Identifier (Item))))
1522 then
1523 Append_To
1524 (Result,
1525 Make_Field_Attribute (Defining_Identifier (Item)));
1526 end if;
1528 Next (Item);
1529 end loop;
1530 end if;
1532 return Result;
1533 end Make_Field_Attributes;
1535 -- Start of processing for Build_Record_Read_Write_Procedure
1537 begin
1538 -- For the protected type case, use corresponding record
1540 if Is_Protected_Type (Typ) then
1541 Typt := Corresponding_Record_Type (Typ);
1542 else
1543 Typt := Typ;
1544 end if;
1546 -- Note that we do nothing with the discriminants, since Read and
1547 -- Write do not read or write the discriminant values. All handling
1548 -- of discriminants occurs in the Input and Output subprograms.
1550 Rdef := Type_Definition
1551 (Declaration_Node (Base_Type (Underlying_Type (Typt))));
1552 Stms := Empty_List;
1554 -- In record extension case, the fields we want, including the _Parent
1555 -- field representing the parent type, are to be found in the extension.
1556 -- Note that we will naturally process the _Parent field using the type
1557 -- of the parent, and hence its stream attributes, which is appropriate.
1559 if Nkind (Rdef) = N_Derived_Type_Definition then
1560 Rdef := Record_Extension_Part (Rdef);
1562 if Is_Limited_Type (Typt) then
1563 In_Limited_Extension := True;
1564 end if;
1565 end if;
1567 if Present (Component_List (Rdef)) then
1568 Append_List_To (Stms,
1569 Make_Component_List_Attributes (Component_List (Rdef)));
1570 end if;
1572 Build_Stream_Procedure
1573 (Loc, Typ, Decl, Pnam, Stms, Nam = Name_Read);
1574 end Build_Record_Read_Write_Procedure;
1576 ----------------------------------
1577 -- Build_Record_Write_Procedure --
1578 ----------------------------------
1580 procedure Build_Record_Write_Procedure
1581 (Loc : Source_Ptr;
1582 Typ : Entity_Id;
1583 Decl : out Node_Id;
1584 Pnam : out Entity_Id)
1586 begin
1587 Pnam := Make_Stream_Subprogram_Name (Loc, Typ, TSS_Stream_Write);
1588 Build_Record_Read_Write_Procedure (Loc, Typ, Decl, Pnam, Name_Write);
1589 end Build_Record_Write_Procedure;
1591 -------------------------------
1592 -- Build_Stream_Attr_Profile --
1593 -------------------------------
1595 function Build_Stream_Attr_Profile
1596 (Loc : Source_Ptr;
1597 Typ : Entity_Id;
1598 Nam : TSS_Name_Type) return List_Id
1600 Profile : List_Id;
1602 begin
1603 -- (Ada 2005: AI-441): Set the null-excluding attribute because it has
1604 -- no semantic meaning in Ada 95 but it is a requirement in Ada 2005.
1606 Profile := New_List (
1607 Make_Parameter_Specification (Loc,
1608 Defining_Identifier => Make_Defining_Identifier (Loc, Name_S),
1609 Parameter_Type =>
1610 Make_Access_Definition (Loc,
1611 Null_Exclusion_Present => True,
1612 Subtype_Mark => New_Occurrence_Of (
1613 Class_Wide_Type (RTE (RE_Root_Stream_Type)), Loc))));
1615 if Nam /= TSS_Stream_Input then
1616 Append_To (Profile,
1617 Make_Parameter_Specification (Loc,
1618 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
1619 Out_Present => (Nam = TSS_Stream_Read),
1620 Parameter_Type => New_Occurrence_Of (Typ, Loc)));
1621 end if;
1623 return Profile;
1624 end Build_Stream_Attr_Profile;
1626 ---------------------------
1627 -- Build_Stream_Function --
1628 ---------------------------
1630 procedure Build_Stream_Function
1631 (Loc : Source_Ptr;
1632 Typ : Entity_Id;
1633 Decl : out Node_Id;
1634 Fnam : Entity_Id;
1635 Decls : List_Id;
1636 Stms : List_Id)
1638 Spec : Node_Id;
1640 begin
1641 -- Construct function specification
1643 -- (Ada 2005: AI-441): Set the null-excluding attribute because it has
1644 -- no semantic meaning in Ada 95 but it is a requirement in Ada 2005.
1646 Spec :=
1647 Make_Function_Specification (Loc,
1648 Defining_Unit_Name => Fnam,
1650 Parameter_Specifications => New_List (
1651 Make_Parameter_Specification (Loc,
1652 Defining_Identifier => Make_Defining_Identifier (Loc, Name_S),
1653 Parameter_Type =>
1654 Make_Access_Definition (Loc,
1655 Null_Exclusion_Present => True,
1656 Subtype_Mark =>
1657 New_Occurrence_Of
1658 (Class_Wide_Type (RTE (RE_Root_Stream_Type)), Loc)))),
1660 Result_Definition => New_Occurrence_Of (Typ, Loc));
1662 Decl :=
1663 Make_Subprogram_Body (Loc,
1664 Specification => Spec,
1665 Declarations => Decls,
1666 Handled_Statement_Sequence =>
1667 Make_Handled_Sequence_Of_Statements (Loc,
1668 Statements => Stms));
1669 end Build_Stream_Function;
1671 ----------------------------
1672 -- Build_Stream_Procedure --
1673 ----------------------------
1675 procedure Build_Stream_Procedure
1676 (Loc : Source_Ptr;
1677 Typ : Entity_Id;
1678 Decl : out Node_Id;
1679 Pnam : Entity_Id;
1680 Stms : List_Id;
1681 Outp : Boolean)
1683 Spec : Node_Id;
1685 begin
1686 -- Construct procedure specification
1688 -- (Ada 2005: AI-441): Set the null-excluding attribute because it has
1689 -- no semantic meaning in Ada 95 but it is a requirement in Ada 2005.
1691 Spec :=
1692 Make_Procedure_Specification (Loc,
1693 Defining_Unit_Name => Pnam,
1695 Parameter_Specifications => New_List (
1696 Make_Parameter_Specification (Loc,
1697 Defining_Identifier => Make_Defining_Identifier (Loc, Name_S),
1698 Parameter_Type =>
1699 Make_Access_Definition (Loc,
1700 Null_Exclusion_Present => True,
1701 Subtype_Mark =>
1702 New_Occurrence_Of
1703 (Class_Wide_Type (RTE (RE_Root_Stream_Type)), Loc))),
1705 Make_Parameter_Specification (Loc,
1706 Defining_Identifier => Make_Defining_Identifier (Loc, Name_V),
1707 Out_Present => Outp,
1708 Parameter_Type => New_Occurrence_Of (Typ, Loc))));
1710 Decl :=
1711 Make_Subprogram_Body (Loc,
1712 Specification => Spec,
1713 Declarations => Empty_List,
1714 Handled_Statement_Sequence =>
1715 Make_Handled_Sequence_Of_Statements (Loc,
1716 Statements => Stms));
1717 end Build_Stream_Procedure;
1719 -----------------------------
1720 -- Has_Stream_Standard_Rep --
1721 -----------------------------
1723 function Has_Stream_Standard_Rep (U_Type : Entity_Id) return Boolean is
1724 Siz : Uint;
1726 begin
1727 if Has_Non_Standard_Rep (U_Type) then
1728 return False;
1729 end if;
1731 if Has_Stream_Size_Clause (U_Type) then
1732 Siz := Static_Integer (Expression (Stream_Size_Clause (U_Type)));
1733 else
1734 Siz := Esize (First_Subtype (U_Type));
1735 end if;
1737 return Siz = Esize (Root_Type (U_Type));
1738 end Has_Stream_Standard_Rep;
1740 ---------------------------------
1741 -- Make_Stream_Subprogram_Name --
1742 ---------------------------------
1744 function Make_Stream_Subprogram_Name
1745 (Loc : Source_Ptr;
1746 Typ : Entity_Id;
1747 Nam : TSS_Name_Type) return Entity_Id
1749 Sname : Name_Id;
1751 begin
1752 -- For tagged types, we are dealing with a TSS associated with the
1753 -- declaration, so we use the standard primitive function name. For
1754 -- other types, generate a local TSS name since we are generating
1755 -- the subprogram at the point of use.
1757 if Is_Tagged_Type (Typ) then
1758 Sname := Make_TSS_Name (Typ, Nam);
1759 else
1760 Sname := Make_TSS_Name_Local (Typ, Nam);
1761 end if;
1763 return Make_Defining_Identifier (Loc, Sname);
1764 end Make_Stream_Subprogram_Name;
1766 ----------------------
1767 -- Stream_Base_Type --
1768 ----------------------
1770 function Stream_Base_Type (E : Entity_Id) return Entity_Id is
1771 begin
1772 if Is_Array_Type (E)
1773 and then Is_First_Subtype (E)
1774 then
1775 return E;
1776 else
1777 return Base_Type (E);
1778 end if;
1779 end Stream_Base_Type;
1781 end Exp_Strm;