gcc/ada/exp_imgv.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                             E X P _ I M G V                              --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --          Copyright (C) 2001-2008, 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 ------------------------------------------------------------------------------
  25
  26 with Atree;    use Atree;
  27 with Casing;   use Casing;
  28 with Checks;   use Checks;
  29 with Einfo;    use Einfo;
  30 with Exp_Util; use Exp_Util;
  31 with Lib;      use Lib;
  32 with Namet;    use Namet;
  33 with Nmake;    use Nmake;
  34 with Nlists;   use Nlists;
  35 with Opt;      use Opt;
  36 with Rtsfind;  use Rtsfind;
  37 with Sem_Aux;  use Sem_Aux;
  38 with Sem_Res;  use Sem_Res;
  39 with Sinfo;    use Sinfo;
  40 with Snames;   use Snames;
  41 with Stand;    use Stand;
  42 with Stringt;  use Stringt;
  43 with Tbuild;   use Tbuild;
  44 with Ttypes;   use Ttypes;
  45 with Uintp;    use Uintp;
  46
  47 package body Exp_Imgv is
  48
  49    ------------------------------------
  50    -- Build_Enumeration_Image_Tables --
  51    ------------------------------------
  52
  53    procedure Build_Enumeration_Image_Tables (E : Entity_Id; N : Node_Id) is
  54       Loc  : constant Source_Ptr := Sloc (E);
  55       Str  : String_Id;
  56       Ind  : List_Id;
  57       Lit  : Entity_Id;
  58       Nlit : Nat;
  59       Len  : Nat;
  60       Estr : Entity_Id;
  61       Eind : Entity_Id;
  62       Ityp : Node_Id;
  63
  64    begin
  65       --  Nothing to do for other than a root enumeration type
  66
  67       if E /= Root_Type (E) then
  68          return;
  69
  70       --  Nothing to do if pragma Discard_Names applies
  71
  72       elsif Discard_Names (E) then
  73          return;
  74       end if;
  75
  76       --  Otherwise tables need constructing
  77
  78       Start_String;
  79       Ind := New_List;
  80       Lit := First_Literal (E);
  81       Len := 1;
  82       Nlit := 0;
  83
  84       loop
  85          Append_To (Ind,
  86            Make_Integer_Literal (Loc, UI_From_Int (Len)));
  87
  88          exit when No (Lit);
  89          Nlit := Nlit + 1;
  90
  91          Get_Unqualified_Decoded_Name_String (Chars (Lit));
  92
  93          if Name_Buffer (1) /= ''' then
  94             Set_Casing (All_Upper_Case);
  95          end if;
  96
  97          Store_String_Chars (Name_Buffer (1 .. Name_Len));
  98          Len := Len + Int (Name_Len);
  99          Next_Literal (Lit);
 100       end loop;
 101
 102       if Len < Int (2 ** (8 - 1)) then
 103          Ityp := Standard_Integer_8;
 104       elsif Len < Int (2 ** (16 - 1)) then
 105          Ityp := Standard_Integer_16;
 106       else
 107          Ityp := Standard_Integer_32;
 108       end if;
 109
 110       Str := End_String;
 111
 112       Estr :=
 113         Make_Defining_Identifier (Loc,
 114           Chars => New_External_Name (Chars (E), 'S'));
 115
 116       Eind :=
 117         Make_Defining_Identifier (Loc,
 118           Chars => New_External_Name (Chars (E), 'N'));
 119
 120       Set_Lit_Strings (E, Estr);
 121       Set_Lit_Indexes (E, Eind);
 122
 123       Insert_Actions (N,
 124         New_List (
 125           Make_Object_Declaration (Loc,
 126             Defining_Identifier => Estr,
 127             Constant_Present    => True,
 128             Object_Definition   =>
 129               New_Occurrence_Of (Standard_String, Loc),
 130             Expression          =>
 131               Make_String_Literal (Loc,
 132                 Strval => Str)),
 133
 134           Make_Object_Declaration (Loc,
 135             Defining_Identifier => Eind,
 136             Constant_Present    => True,
 137
 138             Object_Definition =>
 139               Make_Constrained_Array_Definition (Loc,
 140                 Discrete_Subtype_Definitions => New_List (
 141                   Make_Range (Loc,
 142                     Low_Bound  => Make_Integer_Literal (Loc, 0),
 143                     High_Bound => Make_Integer_Literal (Loc, Nlit))),
 144                 Component_Definition =>
 145                   Make_Component_Definition (Loc,
 146                     Aliased_Present    => False,
 147                     Subtype_Indication => New_Occurrence_Of (Ityp, Loc))),
 148
 149             Expression          =>
 150               Make_Aggregate (Loc,
 151                 Expressions => Ind))),
 152         Suppress => All_Checks);
 153    end Build_Enumeration_Image_Tables;
 154
 155    ----------------------------
 156    -- Expand_Image_Attribute --
 157    ----------------------------
 158
 159    --  For all cases other than user defined enumeration types, the scheme
 160    --  is as follows. First we insert the following code:
 161
 162    --    Snn : String (1 .. rt'Width);
 163    --    Pnn : Natural;
 164    --    Image_xx (tv, Snn, Pnn [,pm]);
 165    --
 166    --  and then Expr is replaced by Snn (1 .. Pnn)
 167
 168    --  In the above expansion:
 169
 170    --    rt is the root type of the expression
 171    --    tv is the expression with the value, usually a type conversion
 172    --    pm is an extra parameter present in some cases
 173
 174    --  The following table shows tv, xx, and (if used) pm for the various
 175    --  possible types of the argument:
 176
 177    --    For types whose root type is Character
 178    --      xx = Character
 179    --      tv = Character (Expr)
 180
 181    --    For types whose root type is Boolean
 182    --      xx = Boolean
 183    --      tv = Boolean (Expr)
 184
 185    --    For signed integer types with size <= Integer'Size
 186    --      xx = Integer
 187    --      tv = Integer (Expr)
 188
 189    --    For other signed integer types
 190    --      xx = Long_Long_Integer
 191    --      tv = Long_Long_Integer (Expr)
 192
 193    --    For modular types with modulus <= System.Unsigned_Types.Unsigned
 194    --      xx = Unsigned
 195    --      tv = System.Unsigned_Types.Unsigned (Expr)
 196
 197    --    For other modular integer types
 198    --      xx = Long_Long_Unsigned
 199    --      tv = System.Unsigned_Types.Long_Long_Unsigned (Expr)
 200
 201    --    For types whose root type is Wide_Character
 202    --      xx = Wide_Character
 203    --      tv = Wide_Character (Expr)
 204    --      pm = Boolean, true if Ada 2005 mode, False otherwise
 205
 206    --    For types whose root type is Wide_Wide_Character
 207    --      xx = Wide_Wide_Character
 208    --      tv = Wide_Wide_Character (Expr)
 209
 210    --    For floating-point types
 211    --      xx = Floating_Point
 212    --      tv = Long_Long_Float (Expr)
 213    --      pm = typ'Digits (typ = subtype of expression)
 214
 215    --    For ordinary fixed-point types
 216    --      xx = Ordinary_Fixed_Point
 217    --      tv = Long_Long_Float (Expr)
 218    --      pm = typ'Aft (typ = subtype of expression)
 219
 220    --    For decimal fixed-point types with size = Integer'Size
 221    --      xx = Decimal
 222    --      tv = Integer (Expr)
 223    --      pm = typ'Scale (typ = subtype of expression)
 224
 225    --    For decimal fixed-point types with size > Integer'Size
 226    --      xx = Long_Long_Decimal
 227    --      tv = Long_Long_Integer?(Expr) [convert with no scaling]
 228    --      pm = typ'Scale (typ = subtype of expression)
 229
 230    --  For enumeration types other than those declared packages Standard
 231    --  or System, Snn, Pnn, are expanded as above, but the call looks like:
 232
 233    --    Image_Enumeration_NN (rt'Pos (X), Snn, Pnn, typS, typI'Address)
 234
 235    --  where rt is the root type of the expression, and typS and typI are
 236    --  the entities constructed as described in the spec for the procedure
 237    --  Build_Enumeration_Image_Tables and NN is 32/16/8 depending on the
 238    --  element type of Lit_Indexes. The rewriting of the expression to
 239    --  Snn (1 .. Pnn) then occurs as in the other cases. A special case is
 240    --  when pragma Discard_Names applies, in which case we replace expr by:
 241
 242    --    Missing ???
 243
 244    procedure Expand_Image_Attribute (N : Node_Id) is
 245       Loc       : constant Source_Ptr := Sloc (N);
 246       Exprs     : constant List_Id    := Expressions (N);
 247       Pref      : constant Node_Id    := Prefix (N);
 248       Ptyp      : constant Entity_Id  := Entity (Pref);
 249       Rtyp      : constant Entity_Id  := Root_Type (Ptyp);
 250       Expr      : constant Node_Id    := Relocate_Node (First (Exprs));
 251       Imid      : RE_Id;
 252       Tent      : Entity_Id;
 253       Ttyp      : Entity_Id;
 254       Proc_Ent  : Entity_Id;
 255       Enum_Case : Boolean;
 256
 257       Arg_List : List_Id;
 258       --  List of arguments for run-time procedure call
 259
 260       Ins_List : List_Id;
 261       --  List of actions to be inserted
 262
 263       Snn : constant Entity_Id :=
 264               Make_Defining_Identifier (Loc,
 265                 Chars => New_Internal_Name ('S'));
 266
 267       Pnn : constant Entity_Id :=
 268               Make_Defining_Identifier (Loc,
 269                 Chars => New_Internal_Name ('P'));
 270
 271    begin
 272       --  Build declarations of Snn and Pnn to be inserted
 273
 274       Ins_List := New_List (
 275
 276          --  Snn : String (1 .. typ'Width);
 277
 278          Make_Object_Declaration (Loc,
 279             Defining_Identifier => Snn,
 280             Object_Definition   =>
 281               Make_Subtype_Indication (Loc,
 282                 Subtype_Mark => New_Occurrence_Of (Standard_String, Loc),
 283                 Constraint   =>
 284                   Make_Index_Or_Discriminant_Constraint (Loc,
 285                     Constraints => New_List (
 286                       Make_Range (Loc,
 287                         Low_Bound  => Make_Integer_Literal (Loc, 1),
 288                         High_Bound =>
 289                           Make_Attribute_Reference (Loc,
 290                             Prefix         => New_Occurrence_Of (Rtyp, Loc),
 291                             Attribute_Name => Name_Width)))))),
 292
 293          --  Pnn : Natural;
 294
 295          Make_Object_Declaration (Loc,
 296            Defining_Identifier => Pnn,
 297            Object_Definition   => New_Occurrence_Of (Standard_Natural, Loc)));
 298
 299       --  Set Imid (RE_Id of procedure to call), and Tent, target for the
 300       --  type conversion of the first argument for all possibilities.
 301
 302       Enum_Case := False;
 303
 304       if Rtyp = Standard_Boolean then
 305          Imid := RE_Image_Boolean;
 306          Tent := Rtyp;
 307
 308       elsif Rtyp = Standard_Character then
 309          Imid := RE_Image_Character;
 310          Tent := Rtyp;
 311
 312       elsif Rtyp = Standard_Wide_Character then
 313          Imid := RE_Image_Wide_Character;
 314          Tent := Rtyp;
 315
 316       elsif Rtyp = Standard_Wide_Wide_Character then
 317          Imid := RE_Image_Wide_Wide_Character;
 318          Tent := Rtyp;
 319
 320       elsif Is_Signed_Integer_Type (Rtyp) then
 321          if Esize (Rtyp) <= Esize (Standard_Integer) then
 322             Imid := RE_Image_Integer;
 323             Tent := Standard_Integer;
 324          else
 325             Imid := RE_Image_Long_Long_Integer;
 326             Tent := Standard_Long_Long_Integer;
 327          end if;
 328
 329       elsif Is_Modular_Integer_Type (Rtyp) then
 330          if Modulus (Rtyp) <= Modulus (RTE (RE_Unsigned)) then
 331             Imid := RE_Image_Unsigned;
 332             Tent := RTE (RE_Unsigned);
 333          else
 334             Imid := RE_Image_Long_Long_Unsigned;
 335             Tent := RTE (RE_Long_Long_Unsigned);
 336          end if;
 337
 338       elsif Is_Decimal_Fixed_Point_Type (Rtyp) then
 339          if UI_To_Int (Esize (Rtyp)) <= Standard_Integer_Size then
 340             Imid := RE_Image_Decimal;
 341             Tent := Standard_Integer;
 342          else
 343             Imid := RE_Image_Long_Long_Decimal;
 344             Tent := Standard_Long_Long_Integer;
 345          end if;
 346
 347       elsif Is_Ordinary_Fixed_Point_Type (Rtyp) then
 348          Imid := RE_Image_Ordinary_Fixed_Point;
 349          Tent := Standard_Long_Long_Float;
 350
 351       elsif Is_Floating_Point_Type (Rtyp) then
 352          Imid := RE_Image_Floating_Point;
 353          Tent := Standard_Long_Long_Float;
 354
 355       --  Only other possibility is user defined enumeration type
 356
 357       else
 358          if Discard_Names (First_Subtype (Ptyp))
 359            or else No (Lit_Strings (Root_Type (Ptyp)))
 360          then
 361             --  When pragma Discard_Names applies to the first subtype,
 362             --  then build (Pref'Pos)'Img.
 363
 364             Rewrite (N,
 365               Make_Attribute_Reference (Loc,
 366                 Prefix =>
 367                    Make_Attribute_Reference (Loc,
 368                      Prefix         => Pref,
 369                      Attribute_Name => Name_Pos,
 370                      Expressions    => New_List (Expr)),
 371                 Attribute_Name =>
 372                   Name_Img));
 373             Analyze_And_Resolve (N, Standard_String);
 374             return;
 375
 376          else
 377             --  Here for enumeration type case
 378
 379             Ttyp := Component_Type (Etype (Lit_Indexes (Rtyp)));
 380
 381             if Ttyp = Standard_Integer_8 then
 382                Imid := RE_Image_Enumeration_8;
 383             elsif Ttyp = Standard_Integer_16  then
 384                Imid := RE_Image_Enumeration_16;
 385             else
 386                Imid := RE_Image_Enumeration_32;
 387             end if;
 388
 389             --  Apply a validity check, since it is a bit drastic to get a
 390             --  completely junk image value for an invalid value.
 391
 392             if not Expr_Known_Valid (Expr) then
 393                Insert_Valid_Check (Expr);
 394             end if;
 395
 396             Enum_Case := True;
 397          end if;
 398       end if;
 399
 400       --  Build first argument for call
 401
 402       if Enum_Case then
 403          Arg_List := New_List (
 404            Make_Attribute_Reference (Loc,
 405              Attribute_Name => Name_Pos,
 406              Prefix         => New_Occurrence_Of (Ptyp, Loc),
 407              Expressions    => New_List (Expr)));
 408
 409       else
 410          Arg_List := New_List (Convert_To (Tent, Expr));
 411       end if;
 412
 413       --  Append Snn, Pnn arguments
 414
 415       Append_To (Arg_List, New_Occurrence_Of (Snn, Loc));
 416       Append_To (Arg_List, New_Occurrence_Of (Pnn, Loc));
 417
 418       --  Get entity of procedure to call
 419
 420       Proc_Ent := RTE (Imid);
 421
 422       --  If the procedure entity is empty, that means we have a case in
 423       --  no run time mode where the operation is not allowed, and an
 424       --  appropriate diagnostic has already been issued.
 425
 426       if No (Proc_Ent) then
 427          return;
 428       end if;
 429
 430       --  Otherwise complete preparation of arguments for run-time call
 431
 432       --  Add extra arguments for Enumeration case
 433
 434       if Enum_Case then
 435          Append_To (Arg_List, New_Occurrence_Of (Lit_Strings (Rtyp), Loc));
 436          Append_To (Arg_List,
 437            Make_Attribute_Reference (Loc,
 438              Prefix         => New_Occurrence_Of (Lit_Indexes (Rtyp), Loc),
 439              Attribute_Name => Name_Address));
 440
 441       --  For floating-point types, append Digits argument
 442
 443       elsif Is_Floating_Point_Type (Rtyp) then
 444          Append_To (Arg_List,
 445            Make_Attribute_Reference (Loc,
 446              Prefix         => New_Reference_To (Ptyp, Loc),
 447              Attribute_Name => Name_Digits));
 448
 449       --  For ordinary fixed-point types, append Aft parameter
 450
 451       elsif Is_Ordinary_Fixed_Point_Type (Rtyp) then
 452          Append_To (Arg_List,
 453            Make_Attribute_Reference (Loc,
 454              Prefix         => New_Reference_To (Ptyp, Loc),
 455              Attribute_Name => Name_Aft));
 456
 457       --  For decimal, append Scale and also set to do literal conversion
 458
 459       elsif Is_Decimal_Fixed_Point_Type (Rtyp) then
 460          Append_To (Arg_List,
 461            Make_Attribute_Reference (Loc,
 462              Prefix => New_Reference_To (Ptyp, Loc),
 463              Attribute_Name => Name_Scale));
 464
 465          Set_Conversion_OK (First (Arg_List));
 466          Set_Etype (First (Arg_List), Tent);
 467
 468          --  For Wide_Character, append Ada 2005 indication
 469
 470       elsif Rtyp = Standard_Wide_Character then
 471          Append_To (Arg_List,
 472            New_Reference_To (Boolean_Literals (Ada_Version >= Ada_05), Loc));
 473       end if;
 474
 475       --  Now append the procedure call to the insert list
 476
 477       Append_To (Ins_List,
 478          Make_Procedure_Call_Statement (Loc,
 479           Name                   => New_Reference_To (Proc_Ent, Loc),
 480           Parameter_Associations => Arg_List));
 481
 482       --  Insert declarations of Snn, Pnn, and the procedure call. We suppress
 483       --  checks because we are sure that everything is in range at this stage.
 484
 485       Insert_Actions (N, Ins_List, Suppress => All_Checks);
 486
 487       --  Final step is to rewrite the expression as a slice and analyze,
 488       --  again with no checks, since we are sure that everything is OK.
 489
 490       Rewrite (N,
 491         Make_Slice (Loc,
 492           Prefix         => New_Occurrence_Of (Snn, Loc),
 493           Discrete_Range =>
 494             Make_Range (Loc,
 495               Low_Bound  => Make_Integer_Literal (Loc, 1),
 496               High_Bound => New_Occurrence_Of (Pnn, Loc))));
 497
 498       Analyze_And_Resolve (N, Standard_String, Suppress => All_Checks);
 499    end Expand_Image_Attribute;
 500
 501    ----------------------------
 502    -- Expand_Value_Attribute --
 503    ----------------------------
 504
 505    --  For scalar types derived from Boolean, Character and integer types
 506    --  in package Standard, typ'Value (X) expands into:
 507
 508    --    btyp (Value_xx (X))
 509
 510    --  where btyp is he base type of the prefix
 511
 512    --    For types whose root type is Character
 513    --      xx = Character
 514
 515    --    For types whose root type is Wide_Character
 516    --      xx = Wide_Character
 517
 518    --    For types whose root type is Wide_Wide_Character
 519    --      xx = Wide_Wide_Character
 520
 521    --    For types whose root type is Boolean
 522    --      xx = Boolean
 523
 524    --    For signed integer types with size <= Integer'Size
 525    --      xx = Integer
 526
 527    --    For other signed integer types
 528    --      xx = Long_Long_Integer
 529
 530    --    For modular types with modulus <= System.Unsigned_Types.Unsigned
 531    --      xx = Unsigned
 532
 533    --    For other modular integer types
 534    --      xx = Long_Long_Unsigned
 535
 536    --    For floating-point types and ordinary fixed-point types
 537    --      xx = Real
 538
 539    --  For Wide_[Wide_]Character types, typ'Value (X) expands into:
 540
 541    --    btyp (Value_xx (X, EM))
 542
 543    --  where btyp is the base type of the prefix, and EM is the encoding method
 544
 545    --  For decimal types with size <= Integer'Size, typ'Value (X)
 546    --  expands into
 547
 548    --    btyp?(Value_Decimal (X, typ'Scale));
 549
 550    --  For all other decimal types, typ'Value (X) expands into
 551
 552    --    btyp?(Value_Long_Long_Decimal (X, typ'Scale))
 553
 554    --  For enumeration types other than those derived from types Boolean,
 555    --  Character, Wide_[Wide_]Character in Standard, typ'Value (X) expands to:
 556
 557    --    Enum'Val (Value_Enumeration_NN (typS, typI'Address, Num, X))
 558
 559    --  where typS and typI and the Lit_Strings and Lit_Indexes entities
 560    --  from T's root type entity, and Num is Enum'Pos (Enum'Last). The
 561    --  Value_Enumeration_NN function will search the tables looking for
 562    --  X and return the position number in the table if found which is
 563    --  used to provide the result of 'Value (using Enum'Val). If the
 564    --  value is not found Constraint_Error is raised. The suffix _NN
 565    --  depends on the element type of typI.
 566
 567    procedure Expand_Value_Attribute (N : Node_Id) is
 568       Loc   : constant Source_Ptr := Sloc (N);
 569       Typ   : constant Entity_Id  := Etype (N);
 570       Btyp  : constant Entity_Id  := Base_Type (Typ);
 571       Rtyp  : constant Entity_Id  := Root_Type (Typ);
 572       Exprs : constant List_Id    := Expressions (N);
 573       Vid   : RE_Id;
 574       Args  : List_Id;
 575       Func  : RE_Id;
 576       Ttyp  : Entity_Id;
 577
 578    begin
 579       Args := Exprs;
 580
 581       if Rtyp = Standard_Character then
 582          Vid := RE_Value_Character;
 583
 584       elsif Rtyp = Standard_Boolean then
 585          Vid := RE_Value_Boolean;
 586
 587       elsif Rtyp = Standard_Wide_Character then
 588          Vid := RE_Value_Wide_Character;
 589
 590          Append_To (Args,
 591            Make_Integer_Literal (Loc,
 592              Intval => Int (Wide_Character_Encoding_Method)));
 593
 594       elsif Rtyp = Standard_Wide_Wide_Character then
 595          Vid := RE_Value_Wide_Wide_Character;
 596
 597          Append_To (Args,
 598            Make_Integer_Literal (Loc,
 599              Intval => Int (Wide_Character_Encoding_Method)));
 600
 601       elsif     Rtyp = Base_Type (Standard_Short_Short_Integer)
 602         or else Rtyp = Base_Type (Standard_Short_Integer)
 603         or else Rtyp = Base_Type (Standard_Integer)
 604       then
 605          Vid := RE_Value_Integer;
 606
 607       elsif Is_Signed_Integer_Type (Rtyp) then
 608          Vid := RE_Value_Long_Long_Integer;
 609
 610       elsif Is_Modular_Integer_Type (Rtyp) then
 611          if Modulus (Rtyp) <= Modulus (RTE (RE_Unsigned)) then
 612             Vid := RE_Value_Unsigned;
 613          else
 614             Vid := RE_Value_Long_Long_Unsigned;
 615          end if;
 616
 617       elsif Is_Decimal_Fixed_Point_Type (Rtyp) then
 618          if UI_To_Int (Esize (Rtyp)) <= Standard_Integer_Size then
 619             Vid := RE_Value_Decimal;
 620          else
 621             Vid := RE_Value_Long_Long_Decimal;
 622          end if;
 623
 624          Append_To (Args,
 625            Make_Attribute_Reference (Loc,
 626              Prefix => New_Reference_To (Typ, Loc),
 627              Attribute_Name => Name_Scale));
 628
 629          Rewrite (N,
 630            OK_Convert_To (Btyp,
 631              Make_Function_Call (Loc,
 632                Name => New_Reference_To (RTE (Vid), Loc),
 633                Parameter_Associations => Args)));
 634
 635          Set_Etype (N, Btyp);
 636          Analyze_And_Resolve (N, Btyp);
 637          return;
 638
 639       elsif Is_Real_Type (Rtyp) then
 640          Vid := RE_Value_Real;
 641
 642       --  Only other possibility is user defined enumeration type
 643
 644       else
 645          pragma Assert (Is_Enumeration_Type (Rtyp));
 646
 647          --  Case of pragma Discard_Names, transform the Value
 648          --  attribute to Btyp'Val (Long_Long_Integer'Value (Args))
 649
 650          if Discard_Names (First_Subtype (Typ))
 651            or else No (Lit_Strings (Rtyp))
 652          then
 653             Rewrite (N,
 654               Make_Attribute_Reference (Loc,
 655                 Prefix => New_Reference_To (Btyp, Loc),
 656                 Attribute_Name => Name_Val,
 657                 Expressions => New_List (
 658                   Make_Attribute_Reference (Loc,
 659                     Prefix =>
 660                       New_Occurrence_Of (Standard_Long_Long_Integer, Loc),
 661                     Attribute_Name => Name_Value,
 662                     Expressions => Args))));
 663
 664             Analyze_And_Resolve (N, Btyp);
 665
 666          --  Here for normal case where we have enumeration tables, this
 667          --  is where we build
 668
 669          --    T'Val (Value_Enumeration_NN (typS, typI'Address, Num, X))
 670
 671          else
 672             Ttyp := Component_Type (Etype (Lit_Indexes (Rtyp)));
 673
 674             if Ttyp = Standard_Integer_8 then
 675                Func := RE_Value_Enumeration_8;
 676             elsif Ttyp = Standard_Integer_16  then
 677                Func := RE_Value_Enumeration_16;
 678             else
 679                Func := RE_Value_Enumeration_32;
 680             end if;
 681
 682             Prepend_To (Args,
 683               Make_Attribute_Reference (Loc,
 684                 Prefix => New_Occurrence_Of (Rtyp, Loc),
 685                 Attribute_Name => Name_Pos,
 686                 Expressions => New_List (
 687                   Make_Attribute_Reference (Loc,
 688                     Prefix => New_Occurrence_Of (Rtyp, Loc),
 689                     Attribute_Name => Name_Last))));
 690
 691             Prepend_To (Args,
 692               Make_Attribute_Reference (Loc,
 693                 Prefix => New_Occurrence_Of (Lit_Indexes (Rtyp), Loc),
 694                 Attribute_Name => Name_Address));
 695
 696             Prepend_To (Args,
 697               New_Occurrence_Of (Lit_Strings (Rtyp), Loc));
 698
 699             Rewrite (N,
 700               Make_Attribute_Reference (Loc,
 701                 Prefix => New_Reference_To (Typ, Loc),
 702                 Attribute_Name => Name_Val,
 703                 Expressions => New_List (
 704                   Make_Function_Call (Loc,
 705                     Name =>
 706                       New_Reference_To (RTE (Func), Loc),
 707                     Parameter_Associations => Args))));
 708
 709             Analyze_And_Resolve (N, Btyp);
 710          end if;
 711
 712          return;
 713       end if;
 714
 715       --  Fall through for all cases except user defined enumeration type
 716       --  and decimal types, with Vid set to the Id of the entity for the
 717       --  Value routine and Args set to the list of parameters for the call.
 718
 719       --  Compiling package Ada.Tags under No_Run_Time_Mode we disable the
 720       --  expansion of the attribute into the function call statement to avoid
 721       --  generating spurious errors caused by the use of Integer_Address'Value
 722       --  in our implementation of Ada.Tags.Internal_Tag
 723
 724       --  Seems like a bit of a kludge, there should be a better way ???
 725
 726       --  There is a better way, you should also test RTE_Available ???
 727
 728       if No_Run_Time_Mode
 729         and then Rtyp = RTE (RE_Integer_Address)
 730         and then RTU_Loaded (Ada_Tags)
 731         and then Cunit_Entity (Current_Sem_Unit)
 732                    = Body_Entity (RTU_Entity (Ada_Tags))
 733       then
 734          Rewrite (N,
 735            Unchecked_Convert_To (Rtyp,
 736              Make_Integer_Literal (Loc, Uint_0)));
 737       else
 738          Rewrite (N,
 739            Convert_To (Btyp,
 740              Make_Function_Call (Loc,
 741                Name => New_Reference_To (RTE (Vid), Loc),
 742                Parameter_Associations => Args)));
 743       end if;
 744
 745       Analyze_And_Resolve (N, Btyp);
 746    end Expand_Value_Attribute;
 747
 748    ---------------------------------
 749    -- Expand_Wide_Image_Attribute --
 750    ---------------------------------
 751
 752    --  We expand typ'Wide_Image (X) as follows. First we insert this code:
 753
 754    --    Rnn : Wide_String (1 .. rt'Wide_Width);
 755    --    Lnn : Natural;
 756    --    String_To_Wide_String
 757    --      (typ'Image (Expr), Rnn, Lnn, Wide_Character_Encoding_Method);
 758
 759    --  where rt is the root type of the prefix type
 760
 761    --  Now we replace the Wide_Image reference by
 762
 763    --    Rnn (1 .. Lnn)
 764
 765    --  This works in all cases because String_To_Wide_String converts any
 766    --  wide character escape sequences resulting from the Image call to the
 767    --  proper Wide_Character equivalent
 768
 769    --  not quite right for typ = Wide_Character ???
 770
 771    procedure Expand_Wide_Image_Attribute (N : Node_Id) is
 772       Loc  : constant Source_Ptr := Sloc (N);
 773       Rtyp : constant Entity_Id  := Root_Type (Entity (Prefix (N)));
 774
 775       Rnn : constant Entity_Id :=
 776               Make_Defining_Identifier (Loc,
 777                 Chars => New_Internal_Name ('S'));
 778
 779       Lnn : constant Entity_Id :=
 780               Make_Defining_Identifier (Loc,
 781                 Chars => New_Internal_Name ('P'));
 782
 783    begin
 784       Insert_Actions (N, New_List (
 785
 786          --  Rnn : Wide_String (1 .. base_typ'Width);
 787
 788          Make_Object_Declaration (Loc,
 789             Defining_Identifier => Rnn,
 790             Object_Definition   =>
 791               Make_Subtype_Indication (Loc,
 792                 Subtype_Mark =>
 793                   New_Occurrence_Of (Standard_Wide_String, Loc),
 794                 Constraint   =>
 795                   Make_Index_Or_Discriminant_Constraint (Loc,
 796                     Constraints => New_List (
 797                       Make_Range (Loc,
 798                         Low_Bound  => Make_Integer_Literal (Loc, 1),
 799                         High_Bound =>
 800                           Make_Attribute_Reference (Loc,
 801                             Prefix         => New_Occurrence_Of (Rtyp, Loc),
 802                             Attribute_Name => Name_Wide_Width)))))),
 803
 804          --  Lnn : Natural;
 805
 806          Make_Object_Declaration (Loc,
 807            Defining_Identifier => Lnn,
 808            Object_Definition   => New_Occurrence_Of (Standard_Natural, Loc)),
 809
 810          --    String_To_Wide_String
 811          --      (typ'Image (X), Rnn, Lnn, Wide_Character_Encoding_Method);
 812
 813          Make_Procedure_Call_Statement (Loc,
 814            Name =>
 815              New_Reference_To (RTE (RE_String_To_Wide_String), Loc),
 816
 817            Parameter_Associations => New_List (
 818              Make_Attribute_Reference (Loc,
 819                Prefix         => Prefix (N),
 820                Attribute_Name => Name_Image,
 821                Expressions    => Expressions (N)),
 822              New_Reference_To (Rnn, Loc),
 823              New_Reference_To (Lnn, Loc),
 824              Make_Integer_Literal (Loc,
 825                Intval => Int (Wide_Character_Encoding_Method))))),
 826
 827          --  Suppress checks because we know everything is properly in range
 828
 829          Suppress => All_Checks);
 830
 831       --  Final step is to rewrite the expression as a slice and analyze,
 832       --  again with no checks, since we are sure that everything is OK.
 833
 834       Rewrite (N,
 835         Make_Slice (Loc,
 836           Prefix         => New_Occurrence_Of (Rnn, Loc),
 837           Discrete_Range =>
 838             Make_Range (Loc,
 839               Low_Bound  => Make_Integer_Literal (Loc, 1),
 840               High_Bound => New_Occurrence_Of (Lnn, Loc))));
 841
 842       Analyze_And_Resolve (N, Standard_Wide_String, Suppress => All_Checks);
 843    end Expand_Wide_Image_Attribute;
 844
 845    --------------------------------------
 846    -- Expand_Wide_Wide_Image_Attribute --
 847    --------------------------------------
 848
 849    --  We expand typ'Wide_Wide_Image (X) as follows. First we insert this code:
 850
 851    --    Rnn : Wide_Wide_String (1 .. rt'Wide_Wide_Width);
 852    --    Lnn : Natural;
 853    --    String_To_Wide_Wide_String
 854    --      (typ'Image (Expr), Rnn, Lnn, Wide_Character_Encoding_Method);
 855
 856    --  where rt is the root type of the prefix type
 857
 858    --  Now we replace the Wide_Wide_Image reference by
 859
 860    --    Rnn (1 .. Lnn)
 861
 862    --  This works in all cases because String_To_Wide_Wide_String converts any
 863    --  wide character escape sequences resulting from the Image call to the
 864    --  proper Wide_Wide_Character equivalent
 865
 866    --  not quite right for typ = Wide_Wide_Character ???
 867
 868    procedure Expand_Wide_Wide_Image_Attribute (N : Node_Id) is
 869       Loc  : constant Source_Ptr := Sloc (N);
 870       Rtyp : constant Entity_Id  := Root_Type (Entity (Prefix (N)));
 871
 872       Rnn : constant Entity_Id :=
 873               Make_Defining_Identifier (Loc,
 874                 Chars => New_Internal_Name ('S'));
 875
 876       Lnn : constant Entity_Id :=
 877               Make_Defining_Identifier (Loc,
 878                 Chars => New_Internal_Name ('P'));
 879
 880    begin
 881       Insert_Actions (N, New_List (
 882
 883          --  Rnn : Wide_Wide_String (1 .. rt'Wide_Wide_Width);
 884
 885          Make_Object_Declaration (Loc,
 886             Defining_Identifier => Rnn,
 887             Object_Definition   =>
 888               Make_Subtype_Indication (Loc,
 889                 Subtype_Mark =>
 890                   New_Occurrence_Of (Standard_Wide_Wide_String, Loc),
 891                 Constraint   =>
 892                   Make_Index_Or_Discriminant_Constraint (Loc,
 893                     Constraints => New_List (
 894                       Make_Range (Loc,
 895                         Low_Bound  => Make_Integer_Literal (Loc, 1),
 896                         High_Bound =>
 897                           Make_Attribute_Reference (Loc,
 898                             Prefix         => New_Occurrence_Of (Rtyp, Loc),
 899                             Attribute_Name => Name_Wide_Wide_Width)))))),
 900
 901          --  Lnn : Natural;
 902
 903          Make_Object_Declaration (Loc,
 904            Defining_Identifier => Lnn,
 905            Object_Definition   => New_Occurrence_Of (Standard_Natural, Loc)),
 906
 907          --    String_To_Wide_Wide_String
 908          --      (typ'Image (X), Rnn, Lnn, Wide_Character_Encoding_Method);
 909
 910          Make_Procedure_Call_Statement (Loc,
 911            Name =>
 912              New_Reference_To (RTE (RE_String_To_Wide_Wide_String), Loc),
 913
 914            Parameter_Associations => New_List (
 915              Make_Attribute_Reference (Loc,
 916                Prefix         => Prefix (N),
 917                Attribute_Name => Name_Image,
 918                Expressions    => Expressions (N)),
 919              New_Reference_To (Rnn, Loc),
 920              New_Reference_To (Lnn, Loc),
 921              Make_Integer_Literal (Loc,
 922                Intval => Int (Wide_Character_Encoding_Method))))),
 923
 924          --  Suppress checks because we know everything is properly in range
 925
 926          Suppress => All_Checks);
 927
 928       --  Final step is to rewrite the expression as a slice and analyze,
 929       --  again with no checks, since we are sure that everything is OK.
 930
 931       Rewrite (N,
 932         Make_Slice (Loc,
 933           Prefix         => New_Occurrence_Of (Rnn, Loc),
 934           Discrete_Range =>
 935             Make_Range (Loc,
 936               Low_Bound  => Make_Integer_Literal (Loc, 1),
 937               High_Bound => New_Occurrence_Of (Lnn, Loc))));
 938
 939       Analyze_And_Resolve
 940         (N, Standard_Wide_Wide_String, Suppress => All_Checks);
 941    end Expand_Wide_Wide_Image_Attribute;
 942
 943    ----------------------------
 944    -- Expand_Width_Attribute --
 945    ----------------------------
 946
 947    --  The processing here also handles the case of Wide_[Wide_]Width. With the
 948    --  exceptions noted, the processing is identical
 949
 950    --  For scalar types derived from Boolean, character and integer types
 951    --  in package Standard. Note that the Width attribute is computed at
 952    --  compile time for all cases except those involving non-static sub-
 953    --  types. For such subtypes, typ'[Wide_[Wide_]]Width expands into:
 954
 955    --    Result_Type (xx (yy (Ptyp'First), yy (Ptyp'Last)))
 956
 957    --  where
 958
 959    --    For types whose root type is Character
 960    --      xx = Width_Character
 961    --      yy = Character
 962
 963    --    For types whose root type is Wide_Character
 964    --      xx = Wide_Width_Character
 965    --      yy = Character
 966
 967    --    For types whose root type is Wide_Wide_Character
 968    --      xx = Wide_Wide_Width_Character
 969    --      yy = Character
 970
 971    --    For types whose root type is Boolean
 972    --      xx = Width_Boolean
 973    --      yy = Boolean
 974
 975    --    For signed integer types
 976    --      xx = Width_Long_Long_Integer
 977    --      yy = Long_Long_Integer
 978
 979    --    For modular integer types
 980    --      xx = Width_Long_Long_Unsigned
 981    --      yy = Long_Long_Unsigned
 982
 983    --  For types derived from Wide_Character, typ'Width expands into
 984
 985    --    Result_Type (Width_Wide_Character (
 986    --      Wide_Character (typ'First),
 987    --      Wide_Character (typ'Last),
 988
 989    --  and typ'Wide_Width expands into:
 990
 991    --    Result_Type (Wide_Width_Wide_Character (
 992    --      Wide_Character (typ'First),
 993    --      Wide_Character (typ'Last));
 994
 995    --  and typ'Wide_Wide_Width expands into
 996
 997    --    Result_Type (Wide_Wide_Width_Wide_Character (
 998    --      Wide_Character (typ'First),
 999    --      Wide_Character (typ'Last));
1000
1001    --  For types derived from Wide_Wide_Character, typ'Width expands into
1002
1003    --    Result_Type (Width_Wide_Wide_Character (
1004    --      Wide_Wide_Character (typ'First),
1005    --      Wide_Wide_Character (typ'Last),
1006
1007    --  and typ'Wide_Width expands into:
1008
1009    --    Result_Type (Wide_Width_Wide_Wide_Character (
1010    --      Wide_Wide_Character (typ'First),
1011    --      Wide_Wide_Character (typ'Last));
1012
1013    --  and typ'Wide_Wide_Width expands into
1014
1015    --    Result_Type (Wide_Wide_Width_Wide_Wide_Char (
1016    --      Wide_Wide_Character (typ'First),
1017    --      Wide_Wide_Character (typ'Last));
1018
1019    --  For real types, typ'Width and typ'Wide_[Wide_]Width expand into
1020
1021    --    if Ptyp'First > Ptyp'Last then 0 else btyp'Width end if
1022
1023    --  where btyp is the base type. This looks recursive but it isn't
1024    --  because the base type is always static, and hence the expression
1025    --  in the else is reduced to an integer literal.
1026
1027    --  For user defined enumeration types, typ'Width expands into
1028
1029    --    Result_Type (Width_Enumeration_NN
1030    --                  (typS,
1031    --                   typI'Address,
1032    --                   typ'Pos (typ'First),
1033    --                   typ'Pos (Typ'Last)));
1034
1035    --  and typ'Wide_Width expands into:
1036
1037    --    Result_Type (Wide_Width_Enumeration_NN
1038    --                  (typS,
1039    --                   typI,
1040    --                   typ'Pos (typ'First),
1041    --                   typ'Pos (Typ'Last))
1042    --                   Wide_Character_Encoding_Method);
1043
1044    --  and typ'Wide_Wide_Width expands into:
1045
1046    --    Result_Type (Wide_Wide_Width_Enumeration_NN
1047    --                  (typS,
1048    --                   typI,
1049    --                   typ'Pos (typ'First),
1050    --                   typ'Pos (Typ'Last))
1051    --                   Wide_Character_Encoding_Method);
1052
1053    --  where typS and typI are the enumeration image strings and
1054    --  indexes table, as described in Build_Enumeration_Image_Tables.
1055    --  NN is 8/16/32 for depending on the element type for typI.
1056
1057    procedure Expand_Width_Attribute (N : Node_Id; Attr : Atype := Normal) is
1058       Loc     : constant Source_Ptr := Sloc (N);
1059       Typ     : constant Entity_Id  := Etype (N);
1060       Pref    : constant Node_Id    := Prefix (N);
1061       Ptyp    : constant Entity_Id  := Etype (Pref);
1062       Rtyp    : constant Entity_Id  := Root_Type (Ptyp);
1063       XX      : RE_Id;
1064       YY      : Entity_Id;
1065       Arglist : List_Id;
1066       Ttyp    : Entity_Id;
1067
1068    begin
1069       --  Types derived from Standard.Boolean
1070
1071       if Rtyp = Standard_Boolean then
1072          XX := RE_Width_Boolean;
1073          YY := Rtyp;
1074
1075       --  Types derived from Standard.Character
1076
1077       elsif Rtyp = Standard_Character then
1078          case Attr is
1079             when Normal    => XX := RE_Width_Character;
1080             when Wide      => XX := RE_Wide_Width_Character;
1081             when Wide_Wide => XX := RE_Wide_Wide_Width_Character;
1082          end case;
1083
1084          YY := Rtyp;
1085
1086       --  Types derived from Standard.Wide_Character
1087
1088       elsif Rtyp = Standard_Wide_Character then
1089          case Attr is
1090             when Normal    => XX := RE_Width_Wide_Character;
1091             when Wide      => XX := RE_Wide_Width_Wide_Character;
1092             when Wide_Wide => XX := RE_Wide_Wide_Width_Wide_Character;
1093          end case;
1094
1095          YY := Rtyp;
1096
1097       --  Types derived from Standard.Wide_Wide_Character
1098
1099       elsif Rtyp = Standard_Wide_Wide_Character then
1100          case Attr is
1101             when Normal    => XX := RE_Width_Wide_Wide_Character;
1102             when Wide      => XX := RE_Wide_Width_Wide_Wide_Character;
1103             when Wide_Wide => XX := RE_Wide_Wide_Width_Wide_Wide_Char;
1104          end case;
1105
1106          YY := Rtyp;
1107
1108       --  Signed integer types
1109
1110       elsif Is_Signed_Integer_Type (Rtyp) then
1111          XX := RE_Width_Long_Long_Integer;
1112          YY := Standard_Long_Long_Integer;
1113
1114       --  Modular integer types
1115
1116       elsif Is_Modular_Integer_Type (Rtyp) then
1117          XX := RE_Width_Long_Long_Unsigned;
1118          YY := RTE (RE_Long_Long_Unsigned);
1119
1120       --  Real types
1121
1122       elsif Is_Real_Type (Rtyp) then
1123
1124          Rewrite (N,
1125            Make_Conditional_Expression (Loc,
1126              Expressions => New_List (
1127
1128                Make_Op_Gt (Loc,
1129                  Left_Opnd =>
1130                    Make_Attribute_Reference (Loc,
1131                      Prefix => New_Reference_To (Ptyp, Loc),
1132                      Attribute_Name => Name_First),
1133
1134                  Right_Opnd =>
1135                    Make_Attribute_Reference (Loc,
1136                      Prefix => New_Reference_To (Ptyp, Loc),
1137                      Attribute_Name => Name_Last)),
1138
1139                Make_Integer_Literal (Loc, 0),
1140
1141                Make_Attribute_Reference (Loc,
1142                  Prefix => New_Reference_To (Base_Type (Ptyp), Loc),
1143                  Attribute_Name => Name_Width))));
1144
1145          Analyze_And_Resolve (N, Typ);
1146          return;
1147
1148       --  User defined enumeration types
1149
1150       else
1151          pragma Assert (Is_Enumeration_Type (Rtyp));
1152
1153          if Discard_Names (Rtyp) then
1154
1155             --  This is a configurable run-time, or else a restriction is in
1156             --  effect. In either case the attribute cannot be supported. Force
1157             --  a load error from Rtsfind to generate an appropriate message,
1158             --  as is done with other ZFP violations.
1159
1160             declare
1161                Discard : constant Entity_Id := RTE (RE_Null);
1162                pragma Unreferenced (Discard);
1163             begin
1164                return;
1165             end;
1166          end if;
1167
1168          Ttyp := Component_Type (Etype (Lit_Indexes (Rtyp)));
1169
1170          case Attr is
1171             when Normal =>
1172                if Ttyp = Standard_Integer_8 then
1173                   XX := RE_Width_Enumeration_8;
1174                elsif Ttyp = Standard_Integer_16  then
1175                   XX := RE_Width_Enumeration_16;
1176                else
1177                   XX := RE_Width_Enumeration_32;
1178                end if;
1179
1180             when Wide =>
1181                if Ttyp = Standard_Integer_8 then
1182                   XX := RE_Wide_Width_Enumeration_8;
1183                elsif Ttyp = Standard_Integer_16  then
1184                   XX := RE_Wide_Width_Enumeration_16;
1185                else
1186                   XX := RE_Wide_Width_Enumeration_32;
1187                end if;
1188
1189             when Wide_Wide =>
1190                if Ttyp = Standard_Integer_8 then
1191                   XX := RE_Wide_Wide_Width_Enumeration_8;
1192                elsif Ttyp = Standard_Integer_16  then
1193                   XX := RE_Wide_Wide_Width_Enumeration_16;
1194                else
1195                   XX := RE_Wide_Wide_Width_Enumeration_32;
1196                end if;
1197          end case;
1198
1199          Arglist :=
1200            New_List (
1201              New_Occurrence_Of (Lit_Strings (Rtyp), Loc),
1202
1203              Make_Attribute_Reference (Loc,
1204                Prefix => New_Occurrence_Of (Lit_Indexes (Rtyp), Loc),
1205                Attribute_Name => Name_Address),
1206
1207              Make_Attribute_Reference (Loc,
1208                Prefix => New_Reference_To (Ptyp, Loc),
1209                Attribute_Name => Name_Pos,
1210
1211                Expressions => New_List (
1212                  Make_Attribute_Reference (Loc,
1213                    Prefix => New_Reference_To (Ptyp, Loc),
1214                    Attribute_Name => Name_First))),
1215
1216              Make_Attribute_Reference (Loc,
1217                Prefix => New_Reference_To (Ptyp, Loc),
1218                Attribute_Name => Name_Pos,
1219
1220                Expressions => New_List (
1221                  Make_Attribute_Reference (Loc,
1222                    Prefix => New_Reference_To (Ptyp, Loc),
1223                    Attribute_Name => Name_Last))));
1224
1225          Rewrite (N,
1226            Convert_To (Typ,
1227              Make_Function_Call (Loc,
1228                Name => New_Reference_To (RTE (XX), Loc),
1229                Parameter_Associations => Arglist)));
1230
1231          Analyze_And_Resolve (N, Typ);
1232          return;
1233       end if;
1234
1235       --  If we fall through XX and YY are set
1236
1237       Arglist := New_List (
1238         Convert_To (YY,
1239           Make_Attribute_Reference (Loc,
1240             Prefix => New_Reference_To (Ptyp, Loc),
1241             Attribute_Name => Name_First)),
1242
1243         Convert_To (YY,
1244           Make_Attribute_Reference (Loc,
1245             Prefix => New_Reference_To (Ptyp, Loc),
1246             Attribute_Name => Name_Last)));
1247
1248       Rewrite (N,
1249         Convert_To (Typ,
1250           Make_Function_Call (Loc,
1251             Name => New_Reference_To (RTE (XX), Loc),
1252             Parameter_Associations => Arglist)));
1253
1254       Analyze_And_Resolve (N, Typ);
1255    end Expand_Width_Attribute;
1256
1257 end Exp_Imgv;