1------------------------------------------------------------------------------ 2-- -- 3-- GNAT COMPILER COMPONENTS -- 4-- -- 5-- E X P _ A T T R -- 6-- -- 7-- B o d y -- 8-- -- 9-- Copyright (C) 1992-2003 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 2, or (at your option) any later ver- -- 14-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- 15-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- 16-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- 17-- for more details. You should have received a copy of the GNU General -- 18-- Public License distributed with GNAT; see file COPYING. If not, write -- 19-- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, -- 20-- MA 02111-1307, USA. -- 21-- -- 22-- GNAT was originally developed by the GNAT team at New York University. -- 23-- Extensive contributions were provided by Ada Core Technologies Inc. -- 24-- -- 25------------------------------------------------------------------------------ 26 27with Atree; use Atree; 28with Checks; use Checks; 29with Einfo; use Einfo; 30with Exp_Ch2; use Exp_Ch2; 31with Exp_Ch9; use Exp_Ch9; 32with Exp_Imgv; use Exp_Imgv; 33with Exp_Pakd; use Exp_Pakd; 34with Exp_Strm; use Exp_Strm; 35with Exp_Tss; use Exp_Tss; 36with Exp_Util; use Exp_Util; 37with Gnatvsn; use Gnatvsn; 38with Hostparm; use Hostparm; 39with Lib; use Lib; 40with Namet; use Namet; 41with Nmake; use Nmake; 42with Nlists; use Nlists; 43with Opt; use Opt; 44with Restrict; use Restrict; 45with Rtsfind; use Rtsfind; 46with Sem; use Sem; 47with Sem_Ch7; use Sem_Ch7; 48with Sem_Ch8; use Sem_Ch8; 49with Sem_Eval; use Sem_Eval; 50with Sem_Res; use Sem_Res; 51with Sem_Util; use Sem_Util; 52with Sinfo; use Sinfo; 53with Snames; use Snames; 54with Stand; use Stand; 55with Stringt; use Stringt; 56with Tbuild; use Tbuild; 57with Ttypes; use Ttypes; 58with Uintp; use Uintp; 59with Uname; use Uname; 60with Validsw; use Validsw; 61 62package body Exp_Attr is 63 64 ----------------------- 65 -- Local Subprograms -- 66 ----------------------- 67 68 procedure Compile_Stream_Body_In_Scope 69 (N : Node_Id; 70 Decl : Node_Id; 71 Arr : Entity_Id; 72 Check : Boolean); 73 -- The body for a stream subprogram may be generated outside of the scope 74 -- of the type. If the type is fully private, it may depend on the full 75 -- view of other types (e.g. indices) that are currently private as well. 76 -- We install the declarations of the package in which the type is declared 77 -- before compiling the body in what is its proper environment. The Check 78 -- parameter indicates if checks are to be suppressed for the stream body. 79 -- We suppress checks for array/record reads, since the rule is that these 80 -- are like assignments, out of range values due to uninitialized storage, 81 -- or other invalid values do NOT cause a Constraint_Error to be raised. 82 83 procedure Expand_Fpt_Attribute 84 (N : Node_Id; 85 Rtp : Entity_Id; 86 Nam : Name_Id; 87 Args : List_Id); 88 -- This procedure expands a call to a floating-point attribute function. 89 -- N is the attribute reference node, and Args is a list of arguments to 90 -- be passed to the function call. Rtp is the root type of the floating 91 -- point type involved (used to select the proper generic instantiation 92 -- of the package containing the attribute routines). The Nam argument 93 -- is the attribute processing routine to be called. This is normally 94 -- the same as the attribute name, except in the Unaligned_Valid case. 95 96 procedure Expand_Fpt_Attribute_R (N : Node_Id); 97 -- This procedure expands a call to a floating-point attribute function 98 -- that takes a single floating-point argument. The function to be called 99 -- is always the same as the attribute name. 100 101 procedure Expand_Fpt_Attribute_RI (N : Node_Id); 102 -- This procedure expands a call to a floating-point attribute function 103 -- that takes one floating-point argument and one integer argument. The 104 -- function to be called is always the same as the attribute name. 105 106 procedure Expand_Fpt_Attribute_RR (N : Node_Id); 107 -- This procedure expands a call to a floating-point attribute function 108 -- that takes two floating-point arguments. The function to be called 109 -- is always the same as the attribute name. 110 111 procedure Expand_Pred_Succ (N : Node_Id); 112 -- Handles expansion of Pred or Succ attributes for case of non-real 113 -- operand with overflow checking required. 114 115 function Get_Index_Subtype (N : Node_Id) return Entity_Id; 116 -- Used for Last, Last, and Length, when the prefix is an array type, 117 -- Obtains the corresponding index subtype. 118 119 procedure Expand_Access_To_Type (N : Node_Id); 120 -- A reference to a type within its own scope is resolved to a reference 121 -- to the current instance of the type in its initialization procedure. 122 123 function Find_Inherited_TSS 124 (Typ : Entity_Id; 125 Nam : TSS_Name_Type) return Entity_Id; 126 -- Returns the TSS of name Nam of Typ, or of its closest ancestor defining 127 -- such a TSS. Empty is returned is neither Typ nor any of its ancestors 128 -- have such a TSS. 129 130 function Find_Stream_Subprogram 131 (Typ : Entity_Id; 132 Nam : TSS_Name_Type) return Entity_Id; 133 -- Returns the stream-oriented subprogram attribute for Typ. For tagged 134 -- types, the corresponding primitive operation is looked up, else the 135 -- appropriate TSS from the type itself, or from its closest ancestor 136 -- defining it, is returned. In both cases, inheritance of representation 137 -- aspects is thus taken into account. 138 139 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean; 140 -- Utility for array attributes, returns true on packed constrained 141 -- arrays, and on access to same. 142 143 ---------------------------------- 144 -- Compile_Stream_Body_In_Scope -- 145 ---------------------------------- 146 147 procedure Compile_Stream_Body_In_Scope 148 (N : Node_Id; 149 Decl : Node_Id; 150 Arr : Entity_Id; 151 Check : Boolean) 152 is 153 Installed : Boolean := False; 154 Scop : constant Entity_Id := Scope (Arr); 155 Curr : constant Entity_Id := Current_Scope; 156 157 begin 158 if Is_Hidden (Arr) 159 and then not In_Open_Scopes (Scop) 160 and then Ekind (Scop) = E_Package 161 then 162 New_Scope (Scop); 163 Install_Visible_Declarations (Scop); 164 Install_Private_Declarations (Scop); 165 Installed := True; 166 167 -- The entities in the package are now visible, but the generated 168 -- stream entity must appear in the current scope (usually an 169 -- enclosing stream function) so that itypes all have their proper 170 -- scopes. 171 172 New_Scope (Curr); 173 end if; 174 175 if Check then 176 Insert_Action (N, Decl); 177 else 178 Insert_Action (N, Decl, All_Checks); 179 end if; 180 181 if Installed then 182 183 -- Remove extra copy of current scope, and package itself 184 185 Pop_Scope; 186 End_Package_Scope (Scop); 187 end if; 188 end Compile_Stream_Body_In_Scope; 189 190 --------------------------- 191 -- Expand_Access_To_Type -- 192 --------------------------- 193 194 procedure Expand_Access_To_Type (N : Node_Id) is 195 Loc : constant Source_Ptr := Sloc (N); 196 Typ : constant Entity_Id := Etype (N); 197 Pref : constant Node_Id := Prefix (N); 198 Par : Node_Id; 199 Formal : Entity_Id; 200 201 begin 202 if Is_Entity_Name (Pref) 203 and then Is_Type (Entity (Pref)) 204 then 205 -- If the current instance name denotes a task type, 206 -- then the access attribute is rewritten to be the 207 -- name of the "_task" parameter associated with the 208 -- task type's task body procedure. An unchecked 209 -- conversion is applied to ensure a type match in 210 -- cases of expander-generated calls (e.g., init procs). 211 212 if Is_Task_Type (Entity (Pref)) then 213 Formal := 214 First_Entity (Get_Task_Body_Procedure (Entity (Pref))); 215 216 while Present (Formal) loop 217 exit when Chars (Formal) = Name_uTask; 218 Next_Entity (Formal); 219 end loop; 220 221 pragma Assert (Present (Formal)); 222 223 Rewrite (N, 224 Unchecked_Convert_To (Typ, New_Occurrence_Of (Formal, Loc))); 225 Set_Etype (N, Typ); 226 227 -- The expression must appear in a default expression, 228 -- (which in the initialization procedure is the rhs of 229 -- an assignment), and not in a discriminant constraint. 230 231 else 232 Par := Parent (N); 233 234 while Present (Par) loop 235 exit when Nkind (Par) = N_Assignment_Statement; 236 237 if Nkind (Par) = N_Component_Declaration then 238 return; 239 end if; 240 241 Par := Parent (Par); 242 end loop; 243 244 if Present (Par) then 245 Rewrite (N, 246 Make_Attribute_Reference (Loc, 247 Prefix => Make_Identifier (Loc, Name_uInit), 248 Attribute_Name => Attribute_Name (N))); 249 250 Analyze_And_Resolve (N, Typ); 251 end if; 252 end if; 253 end if; 254 end Expand_Access_To_Type; 255 256 -------------------------- 257 -- Expand_Fpt_Attribute -- 258 -------------------------- 259 260 procedure Expand_Fpt_Attribute 261 (N : Node_Id; 262 Rtp : Entity_Id; 263 Nam : Name_Id; 264 Args : List_Id) 265 is 266 Loc : constant Source_Ptr := Sloc (N); 267 Typ : constant Entity_Id := Etype (N); 268 Pkg : RE_Id; 269 Fnm : Node_Id; 270 271 begin 272 -- The function name is the selected component Fat_xxx.yyy where xxx 273 -- is the floating-point root type, and yyy is the argument Nam. 274 275 -- Note: it would be more usual to have separate RE entries for each 276 -- of the entities in the Fat packages, but first they have identical 277 -- names (so we would have to have lots of renaming declarations to 278 -- meet the normal RE rule of separate names for all runtime entities), 279 -- and second there would be an awful lot of them! 280 281 if Rtp = Standard_Short_Float then 282 Pkg := RE_Fat_Short_Float; 283 elsif Rtp = Standard_Float then 284 Pkg := RE_Fat_Float; 285 elsif Rtp = Standard_Long_Float then 286 Pkg := RE_Fat_Long_Float; 287 else 288 Pkg := RE_Fat_Long_Long_Float; 289 end if; 290 291 Fnm := 292 Make_Selected_Component (Loc, 293 Prefix => New_Reference_To (RTE (Pkg), Loc), 294 Selector_Name => Make_Identifier (Loc, Nam)); 295 296 -- The generated call is given the provided set of parameters, and then 297 -- wrapped in a conversion which converts the result to the target type 298 299 Rewrite (N, 300 Unchecked_Convert_To (Etype (N), 301 Make_Function_Call (Loc, 302 Name => Fnm, 303 Parameter_Associations => Args))); 304 305 Analyze_And_Resolve (N, Typ); 306 end Expand_Fpt_Attribute; 307 308 ---------------------------- 309 -- Expand_Fpt_Attribute_R -- 310 ---------------------------- 311 312 -- The single argument is converted to its root type to call the 313 -- appropriate runtime function, with the actual call being built 314 -- by Expand_Fpt_Attribute 315 316 procedure Expand_Fpt_Attribute_R (N : Node_Id) is 317 E1 : constant Node_Id := First (Expressions (N)); 318 Rtp : constant Entity_Id := Root_Type (Etype (E1)); 319 320 begin 321 Expand_Fpt_Attribute 322 (N, Rtp, Attribute_Name (N), 323 New_List (Unchecked_Convert_To (Rtp, Relocate_Node (E1)))); 324 end Expand_Fpt_Attribute_R; 325 326 ----------------------------- 327 -- Expand_Fpt_Attribute_RI -- 328 ----------------------------- 329 330 -- The first argument is converted to its root type and the second 331 -- argument is converted to standard long long integer to call the 332 -- appropriate runtime function, with the actual call being built 333 -- by Expand_Fpt_Attribute 334 335 procedure Expand_Fpt_Attribute_RI (N : Node_Id) is 336 E1 : constant Node_Id := First (Expressions (N)); 337 Rtp : constant Entity_Id := Root_Type (Etype (E1)); 338 E2 : constant Node_Id := Next (E1); 339 340 begin 341 Expand_Fpt_Attribute 342 (N, Rtp, Attribute_Name (N), 343 New_List ( 344 Unchecked_Convert_To (Rtp, Relocate_Node (E1)), 345 Unchecked_Convert_To (Standard_Integer, Relocate_Node (E2)))); 346 end Expand_Fpt_Attribute_RI; 347 348 ----------------------------- 349 -- Expand_Fpt_Attribute_RR -- 350 ----------------------------- 351 352 -- The two arguments is converted to their root types to call the 353 -- appropriate runtime function, with the actual call being built 354 -- by Expand_Fpt_Attribute 355 356 procedure Expand_Fpt_Attribute_RR (N : Node_Id) is 357 E1 : constant Node_Id := First (Expressions (N)); 358 Rtp : constant Entity_Id := Root_Type (Etype (E1)); 359 E2 : constant Node_Id := Next (E1); 360 361 begin 362 Expand_Fpt_Attribute 363 (N, Rtp, Attribute_Name (N), 364 New_List ( 365 Unchecked_Convert_To (Rtp, Relocate_Node (E1)), 366 Unchecked_Convert_To (Rtp, Relocate_Node (E2)))); 367 end Expand_Fpt_Attribute_RR; 368 369 ---------------------------------- 370 -- Expand_N_Attribute_Reference -- 371 ---------------------------------- 372 373 procedure Expand_N_Attribute_Reference (N : Node_Id) is 374 Loc : constant Source_Ptr := Sloc (N); 375 Typ : constant Entity_Id := Etype (N); 376 Btyp : constant Entity_Id := Base_Type (Typ); 377 Pref : constant Node_Id := Prefix (N); 378 Exprs : constant List_Id := Expressions (N); 379 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N)); 380 381 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id); 382 -- Rewrites a stream attribute for Read, Write or Output with the 383 -- procedure call. Pname is the entity for the procedure to call. 384 385 ------------------------------ 386 -- Rewrite_Stream_Proc_Call -- 387 ------------------------------ 388 389 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id) is 390 Item : constant Node_Id := Next (First (Exprs)); 391 Formal : constant Entity_Id := Next_Formal (First_Formal (Pname)); 392 Formal_Typ : constant Entity_Id := Etype (Formal); 393 Is_Written : constant Boolean := (Ekind (Formal) /= E_In_Parameter); 394 395 begin 396 -- The expansion depends on Item, the second actual, which is 397 -- the object being streamed in or out. 398 399 -- If the item is a component of a packed array type, and 400 -- a conversion is needed on exit, we introduce a temporary to 401 -- hold the value, because otherwise the packed reference will 402 -- not be properly expanded. 403 404 if Nkind (Item) = N_Indexed_Component 405 and then Is_Packed (Base_Type (Etype (Prefix (Item)))) 406 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ) 407 and then Is_Written 408 then 409 declare 410 Temp : constant Entity_Id := 411 Make_Defining_Identifier 412 (Loc, New_Internal_Name ('V')); 413 Decl : Node_Id; 414 Assn : Node_Id; 415 416 begin 417 Decl := 418 Make_Object_Declaration (Loc, 419 Defining_Identifier => Temp, 420 Object_Definition => 421 New_Occurrence_Of (Formal_Typ, Loc)); 422 Set_Etype (Temp, Formal_Typ); 423 424 Assn := 425 Make_Assignment_Statement (Loc, 426 Name => New_Copy_Tree (Item), 427 Expression => 428 Unchecked_Convert_To 429 (Etype (Item), New_Occurrence_Of (Temp, Loc))); 430 431 Rewrite (Item, New_Occurrence_Of (Temp, Loc)); 432 Insert_Actions (N, 433 New_List ( 434 Decl, 435 Make_Procedure_Call_Statement (Loc, 436 Name => New_Occurrence_Of (Pname, Loc), 437 Parameter_Associations => Exprs), 438 Assn)); 439 440 Rewrite (N, Make_Null_Statement (Loc)); 441 return; 442 end; 443 end if; 444 445 -- For the class-wide dispatching cases, and for cases in which 446 -- the base type of the second argument matches the base type of 447 -- the corresponding formal parameter (that is to say the stream 448 -- operation is not inherited), we are all set, and can use the 449 -- argument unchanged. 450 451 -- For all other cases we do an unchecked conversion of the second 452 -- parameter to the type of the formal of the procedure we are 453 -- calling. This deals with the private type cases, and with going 454 -- to the root type as required in elementary type case. 455 456 if not Is_Class_Wide_Type (Entity (Pref)) 457 and then not Is_Class_Wide_Type (Etype (Item)) 458 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ) 459 then 460 Rewrite (Item, 461 Unchecked_Convert_To (Formal_Typ, Relocate_Node (Item))); 462 463 -- For untagged derived types set Assignment_OK, to prevent 464 -- copies from being created when the unchecked conversion 465 -- is expanded (which would happen in Remove_Side_Effects 466 -- if Expand_N_Unchecked_Conversion were allowed to call 467 -- Force_Evaluation). The copy could violate Ada semantics 468 -- in cases such as an actual that is an out parameter. 469 -- Note that this approach is also used in exp_ch7 for calls 470 -- to controlled type operations to prevent problems with 471 -- actuals wrapped in unchecked conversions. 472 473 if Is_Untagged_Derivation (Etype (Expression (Item))) then 474 Set_Assignment_OK (Item); 475 end if; 476 end if; 477 478 -- And now rewrite the call 479 480 Rewrite (N, 481 Make_Procedure_Call_Statement (Loc, 482 Name => New_Occurrence_Of (Pname, Loc), 483 Parameter_Associations => Exprs)); 484 485 Analyze (N); 486 end Rewrite_Stream_Proc_Call; 487 488 -- Start of processing for Expand_N_Attribute_Reference 489 490 begin 491 -- Do required validity checking 492 493 if Validity_Checks_On and Validity_Check_Operands then 494 declare 495 Expr : Node_Id; 496 497 begin 498 Expr := First (Expressions (N)); 499 while Present (Expr) loop 500 Ensure_Valid (Expr); 501 Next (Expr); 502 end loop; 503 end; 504 end if; 505 506 -- Remaining processing depends on specific attribute 507 508 case Id is 509 510 ------------ 511 -- Access -- 512 ------------ 513 514 when Attribute_Access => 515 516 if Ekind (Btyp) = E_Access_Protected_Subprogram_Type then 517 518 -- The value of the attribute_reference is a record containing 519 -- two fields: an access to the protected object, and an access 520 -- to the subprogram itself. The prefix is a selected component. 521 522 declare 523 Agg : Node_Id; 524 Sub : Entity_Id; 525 E_T : constant Entity_Id := Equivalent_Type (Btyp); 526 Acc : constant Entity_Id := 527 Etype (Next_Component (First_Component (E_T))); 528 Obj_Ref : Node_Id; 529 Curr : Entity_Id; 530 531 begin 532 -- Within the body of the protected type, the prefix 533 -- designates a local operation, and the object is the first 534 -- parameter of the corresponding protected body of the 535 -- current enclosing operation. 536 537 if Is_Entity_Name (Pref) then 538 pragma Assert (In_Open_Scopes (Scope (Entity (Pref)))); 539 Sub := 540 New_Occurrence_Of 541 (Protected_Body_Subprogram (Entity (Pref)), Loc); 542 Curr := Current_Scope; 543 544 while Scope (Curr) /= Scope (Entity (Pref)) loop 545 Curr := Scope (Curr); 546 end loop; 547 548 Obj_Ref := 549 Make_Attribute_Reference (Loc, 550 Prefix => 551 New_Occurrence_Of 552 (First_Formal 553 (Protected_Body_Subprogram (Curr)), Loc), 554 Attribute_Name => Name_Address); 555 556 -- Case where the prefix is not an entity name. Find the 557 -- version of the protected operation to be called from 558 -- outside the protected object. 559 560 else 561 Sub := 562 New_Occurrence_Of 563 (External_Subprogram 564 (Entity (Selector_Name (Pref))), Loc); 565 566 Obj_Ref := 567 Make_Attribute_Reference (Loc, 568 Prefix => Relocate_Node (Prefix (Pref)), 569 Attribute_Name => Name_Address); 570 end if; 571 572 Agg := 573 Make_Aggregate (Loc, 574 Expressions => 575 New_List ( 576 Obj_Ref, 577 Unchecked_Convert_To (Acc, 578 Make_Attribute_Reference (Loc, 579 Prefix => Sub, 580 Attribute_Name => Name_Address)))); 581 582 Rewrite (N, Agg); 583 584 Analyze_And_Resolve (N, E_T); 585 586 -- For subsequent analysis, the node must retain its type. 587 -- The backend will replace it with the equivalent type where 588 -- needed. 589 590 Set_Etype (N, Typ); 591 end; 592 593 elsif Ekind (Btyp) = E_General_Access_Type then 594 declare 595 Ref_Object : constant Node_Id := Get_Referenced_Object (Pref); 596 Parm_Ent : Entity_Id; 597 Conversion : Node_Id; 598 599 begin 600 -- If the prefix of an Access attribute is a dereference of an 601 -- access parameter (or a renaming of such a dereference) and 602 -- the context is a general access type (but not an anonymous 603 -- access type), then rewrite the attribute as a conversion of 604 -- the access parameter to the context access type. This will 605 -- result in an accessibility check being performed, if needed. 606 607 -- (X.all'Access => Acc_Type (X)) 608 609 if Nkind (Ref_Object) = N_Explicit_Dereference 610 and then Is_Entity_Name (Prefix (Ref_Object)) 611 then 612 Parm_Ent := Entity (Prefix (Ref_Object)); 613 614 if Ekind (Parm_Ent) in Formal_Kind 615 and then Ekind (Etype (Parm_Ent)) = E_Anonymous_Access_Type 616 and then Present (Extra_Accessibility (Parm_Ent)) 617 then 618 Conversion := 619 Convert_To (Typ, New_Copy_Tree (Prefix (Ref_Object))); 620 621 Rewrite (N, Conversion); 622 Analyze_And_Resolve (N, Typ); 623 end if; 624 end if; 625 end; 626 627 -- If the prefix is a type name, this is a reference to the current 628 -- instance of the type, within its initialization procedure. 629 630 else 631 Expand_Access_To_Type (N); 632 end if; 633 634 -------------- 635 -- Adjacent -- 636 -------------- 637 638 -- Transforms 'Adjacent into a call to the floating-point attribute 639 -- function Adjacent in Fat_xxx (where xxx is the root type) 640 641 when Attribute_Adjacent => 642 Expand_Fpt_Attribute_RR (N); 643 644 ------------- 645 -- Address -- 646 ------------- 647 648 when Attribute_Address => Address : declare 649 Task_Proc : Entity_Id; 650 651 begin 652 -- If the prefix is a task or a task type, the useful address 653 -- is that of the procedure for the task body, i.e. the actual 654 -- program unit. We replace the original entity with that of 655 -- the procedure. 656 657 if Is_Entity_Name (Pref) 658 and then Is_Task_Type (Entity (Pref)) 659 then 660 Task_Proc := Next_Entity (Root_Type (Etype (Pref))); 661 662 while Present (Task_Proc) loop 663 exit when Ekind (Task_Proc) = E_Procedure 664 and then Etype (First_Formal (Task_Proc)) = 665 Corresponding_Record_Type (Etype (Pref)); 666 Next_Entity (Task_Proc); 667 end loop; 668 669 if Present (Task_Proc) then 670 Set_Entity (Pref, Task_Proc); 671 Set_Etype (Pref, Etype (Task_Proc)); 672 end if; 673 674 -- Similarly, the address of a protected operation is the address 675 -- of the corresponding protected body, regardless of the protected 676 -- object from which it is selected. 677 678 elsif Nkind (Pref) = N_Selected_Component 679 and then Is_Subprogram (Entity (Selector_Name (Pref))) 680 and then Is_Protected_Type (Scope (Entity (Selector_Name (Pref)))) 681 then 682 Rewrite (Pref, 683 New_Occurrence_Of ( 684 External_Subprogram (Entity (Selector_Name (Pref))), Loc)); 685 686 elsif Nkind (Pref) = N_Explicit_Dereference 687 and then Ekind (Etype (Pref)) = E_Subprogram_Type 688 and then Convention (Etype (Pref)) = Convention_Protected 689 then 690 -- The prefix is be a dereference of an access_to_protected_ 691 -- subprogram. The desired address is the second component of 692 -- the record that represents the access. 693 694 declare 695 Addr : constant Entity_Id := Etype (N); 696 Ptr : constant Node_Id := Prefix (Pref); 697 T : constant Entity_Id := 698 Equivalent_Type (Base_Type (Etype (Ptr))); 699 700 begin 701 Rewrite (N, 702 Unchecked_Convert_To (Addr, 703 Make_Selected_Component (Loc, 704 Prefix => Unchecked_Convert_To (T, Ptr), 705 Selector_Name => New_Occurrence_Of ( 706 Next_Entity (First_Entity (T)), Loc)))); 707 708 Analyze_And_Resolve (N, Addr); 709 end; 710 end if; 711 712 -- Deal with packed array reference, other cases are handled by gigi 713 714 if Involves_Packed_Array_Reference (Pref) then 715 Expand_Packed_Address_Reference (N); 716 end if; 717 end Address; 718 719 --------------- 720 -- Alignment -- 721 --------------- 722 723 when Attribute_Alignment => Alignment : declare 724 Ptyp : constant Entity_Id := Etype (Pref); 725 New_Node : Node_Id; 726 727 begin 728 -- For class-wide types, X'Class'Alignment is transformed into a 729 -- direct reference to the Alignment of the class type, so that the 730 -- back end does not have to deal with the X'Class'Alignment 731 -- reference. 732 733 if Is_Entity_Name (Pref) 734 and then Is_Class_Wide_Type (Entity (Pref)) 735 then 736 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc)); 737 return; 738 739 -- For x'Alignment applied to an object of a class wide type, 740 -- transform X'Alignment into a call to the predefined primitive 741 -- operation _Alignment applied to X. 742 743 elsif Is_Class_Wide_Type (Ptyp) then 744 New_Node := 745 Make_Function_Call (Loc, 746 Name => New_Reference_To 747 (Find_Prim_Op (Ptyp, Name_uAlignment), Loc), 748 Parameter_Associations => New_List (Pref)); 749 750 if Typ /= Standard_Integer then 751 752 -- The context is a specific integer type with which the 753 -- original attribute was compatible. The function has a 754 -- specific type as well, so to preserve the compatibility 755 -- we must convert explicitly. 756 757 New_Node := Convert_To (Typ, New_Node); 758 end if; 759 760 Rewrite (N, New_Node); 761 Analyze_And_Resolve (N, Typ); 762 return; 763 764 -- For all other cases, we just have to deal with the case of 765 -- the fact that the result can be universal. 766 767 else 768 Apply_Universal_Integer_Attribute_Checks (N); 769 end if; 770 end Alignment; 771 772 --------------- 773 -- AST_Entry -- 774 --------------- 775 776 when Attribute_AST_Entry => AST_Entry : declare 777 Ttyp : Entity_Id; 778 T_Id : Node_Id; 779 Eent : Entity_Id; 780 781 Entry_Ref : Node_Id; 782 -- The reference to the entry or entry family 783 784 Index : Node_Id; 785 -- The index expression for an entry family reference, or 786 -- the Empty if Entry_Ref references a simple entry. 787 788 begin 789 if Nkind (Pref) = N_Indexed_Component then 790 Entry_Ref := Prefix (Pref); 791 Index := First (Expressions (Pref)); 792 else 793 Entry_Ref := Pref; 794 Index := Empty; 795 end if; 796 797 -- Get expression for Task_Id and the entry entity 798 799 if Nkind (Entry_Ref) = N_Selected_Component then 800 T_Id := 801 Make_Attribute_Reference (Loc, 802 Attribute_Name => Name_Identity, 803 Prefix => Prefix (Entry_Ref)); 804 805 Ttyp := Etype (Prefix (Entry_Ref)); 806 Eent := Entity (Selector_Name (Entry_Ref)); 807 808 else 809 T_Id := 810 Make_Function_Call (Loc, 811 Name => New_Occurrence_Of (RTE (RE_Current_Task), Loc)); 812 813 Eent := Entity (Entry_Ref); 814 815 -- We have to find the enclosing task to get the task type 816 -- There must be one, since we already validated this earlier 817 818 Ttyp := Current_Scope; 819 while not Is_Task_Type (Ttyp) loop 820 Ttyp := Scope (Ttyp); 821 end loop; 822 end if; 823 824 -- Now rewrite the attribute with a call to Create_AST_Handler 825 826 Rewrite (N, 827 Make_Function_Call (Loc, 828 Name => New_Occurrence_Of (RTE (RE_Create_AST_Handler), Loc), 829 Parameter_Associations => New_List ( 830 T_Id, 831 Entry_Index_Expression (Loc, Eent, Index, Ttyp)))); 832 833 Analyze_And_Resolve (N, RTE (RE_AST_Handler)); 834 end AST_Entry; 835 836 ------------------ 837 -- Bit_Position -- 838 ------------------ 839 840 -- We compute this if a component clause was present, otherwise 841 -- we leave the computation up to Gigi, since we don't know what 842 -- layout will be chosen. 843 844 -- Note that the attribute can apply to a naked record component 845 -- in generated code (i.e. the prefix is an identifier that 846 -- references the component or discriminant entity). 847 848 when Attribute_Bit_Position => Bit_Position : 849 declare 850 CE : Entity_Id; 851 852 begin 853 if Nkind (Pref) = N_Identifier then 854 CE := Entity (Pref); 855 else 856 CE := Entity (Selector_Name (Pref)); 857 end if; 858 859 if Known_Static_Component_Bit_Offset (CE) then 860 Rewrite (N, 861 Make_Integer_Literal (Loc, 862 Intval => Component_Bit_Offset (CE))); 863 Analyze_And_Resolve (N, Typ); 864 865 else 866 Apply_Universal_Integer_Attribute_Checks (N); 867 end if; 868 end Bit_Position; 869 870 ------------------ 871 -- Body_Version -- 872 ------------------ 873 874 -- A reference to P'Body_Version or P'Version is expanded to 875 876 -- Vnn : Unsigned; 877 -- pragma Import (C, Vnn, "uuuuT"; 878 -- ... 879 -- Get_Version_String (Vnn) 880 881 -- where uuuu is the unit name (dots replaced by double underscore) 882 -- and T is B for the cases of Body_Version, or Version applied to a 883 -- subprogram acting as its own spec, and S for Version applied to a 884 -- subprogram spec or package. This sequence of code references the 885 -- the unsigned constant created in the main program by the binder. 886 887 -- A special exception occurs for Standard, where the string 888 -- returned is a copy of the library string in gnatvsn.ads. 889 890 when Attribute_Body_Version | Attribute_Version => Version : declare 891 E : constant Entity_Id := 892 Make_Defining_Identifier (Loc, New_Internal_Name ('V')); 893 Pent : Entity_Id := Entity (Pref); 894 S : String_Id; 895 896 begin 897 -- If not library unit, get to containing library unit 898 899 while Pent /= Standard_Standard 900 and then Scope (Pent) /= Standard_Standard 901 loop 902 Pent := Scope (Pent); 903 end loop; 904 905 -- Special case Standard 906 907 if Pent = Standard_Standard 908 or else Pent = Standard_ASCII 909 then 910 Name_Buffer (1 .. Verbose_Library_Version'Length) := 911 Verbose_Library_Version; 912 Name_Len := Verbose_Library_Version'Length; 913 Rewrite (N, 914 Make_String_Literal (Loc, 915 Strval => String_From_Name_Buffer)); 916 917 -- All other cases 918 919 else 920 -- Build required string constant 921 922 Get_Name_String (Get_Unit_Name (Pent)); 923 924 Start_String; 925 for J in 1 .. Name_Len - 2 loop 926 if Name_Buffer (J) = '.' then 927 Store_String_Chars ("__"); 928 else 929 Store_String_Char (Get_Char_Code (Name_Buffer (J))); 930 end if; 931 end loop; 932 933 -- Case of subprogram acting as its own spec, always use body 934 935 if Nkind (Declaration_Node (Pent)) in N_Subprogram_Specification 936 and then Nkind (Parent (Declaration_Node (Pent))) = 937 N_Subprogram_Body 938 and then Acts_As_Spec (Parent (Declaration_Node (Pent))) 939 then 940 Store_String_Chars ("B"); 941 942 -- Case of no body present, always use spec 943 944 elsif not Unit_Requires_Body (Pent) then 945 Store_String_Chars ("S"); 946 947 -- Otherwise use B for Body_Version, S for spec 948 949 elsif Id = Attribute_Body_Version then 950 Store_String_Chars ("B"); 951 else 952 Store_String_Chars ("S"); 953 end if; 954 955 S := End_String; 956 Lib.Version_Referenced (S); 957 958 -- Insert the object declaration 959 960 Insert_Actions (N, New_List ( 961 Make_Object_Declaration (Loc, 962 Defining_Identifier => E, 963 Object_Definition => 964 New_Occurrence_Of (RTE (RE_Unsigned), Loc)))); 965 966 -- Set entity as imported with correct external name 967 968 Set_Is_Imported (E); 969 Set_Interface_Name (E, Make_String_Literal (Loc, S)); 970 971 -- And now rewrite original reference 972 973 Rewrite (N, 974 Make_Function_Call (Loc, 975 Name => New_Reference_To (RTE (RE_Get_Version_String), Loc), 976 Parameter_Associations => New_List ( 977 New_Occurrence_Of (E, Loc)))); 978 end if; 979 980 Analyze_And_Resolve (N, RTE (RE_Version_String)); 981 end Version; 982 983 ------------- 984 -- Ceiling -- 985 ------------- 986 987 -- Transforms 'Ceiling into a call to the floating-point attribute 988 -- function Ceiling in Fat_xxx (where xxx is the root type) 989 990 when Attribute_Ceiling => 991 Expand_Fpt_Attribute_R (N); 992 993 -------------- 994 -- Callable -- 995 -------------- 996 997 -- Transforms 'Callable attribute into a call to the Callable function. 998 999 when Attribute_Callable => Callable : 1000 begin 1001 Rewrite (N, 1002 Build_Call_With_Task (Pref, RTE (RE_Callable))); 1003 Analyze_And_Resolve (N, Standard_Boolean); 1004 end Callable; 1005 1006 ------------ 1007 -- Caller -- 1008 ------------ 1009 1010 -- Transforms 'Caller attribute into a call to either the 1011 -- Task_Entry_Caller or the Protected_Entry_Caller function. 1012 1013 when Attribute_Caller => Caller : declare 1014 Id_Kind : constant Entity_Id := RTE (RO_AT_Task_ID); 1015 Ent : constant Entity_Id := Entity (Pref); 1016 Conctype : constant Entity_Id := Scope (Ent); 1017 Nest_Depth : Integer := 0; 1018 Name : Node_Id; 1019 S : Entity_Id; 1020 1021 begin 1022 -- Protected case 1023 1024 if Is_Protected_Type (Conctype) then 1025 if Abort_Allowed 1026 or else Restrictions (No_Entry_Queue) = False 1027 or else Number_Entries (Conctype) > 1 1028 then 1029 Name := 1030 New_Reference_To 1031 (RTE (RE_Protected_Entry_Caller), Loc); 1032 else 1033 Name := 1034 New_Reference_To 1035 (RTE (RE_Protected_Single_Entry_Caller), Loc); 1036 end if; 1037 1038 Rewrite (N, 1039 Unchecked_Convert_To (Id_Kind, 1040 Make_Function_Call (Loc, 1041 Name => Name, 1042 Parameter_Associations => New_List 1043 (New_Reference_To ( 1044 Object_Ref 1045 (Corresponding_Body (Parent (Conctype))), Loc))))); 1046 1047 -- Task case 1048 1049 else 1050 -- Determine the nesting depth of the E'Caller attribute, that 1051 -- is, how many accept statements are nested within the accept 1052 -- statement for E at the point of E'Caller. The runtime uses 1053 -- this depth to find the specified entry call. 1054 1055 for J in reverse 0 .. Scope_Stack.Last loop 1056 S := Scope_Stack.Table (J).Entity; 1057 1058 -- We should not reach the scope of the entry, as it should 1059 -- already have been checked in Sem_Attr that this attribute 1060 -- reference is within a matching accept statement. 1061 1062 pragma Assert (S /= Conctype); 1063 1064 if S = Ent then 1065 exit; 1066 1067 elsif Is_Entry (S) then 1068 Nest_Depth := Nest_Depth + 1; 1069 end if; 1070 end loop; 1071 1072 Rewrite (N, 1073 Unchecked_Convert_To (Id_Kind, 1074 Make_Function_Call (Loc, 1075 Name => New_Reference_To ( 1076 RTE (RE_Task_Entry_Caller), Loc), 1077 Parameter_Associations => New_List ( 1078 Make_Integer_Literal (Loc, 1079 Intval => Int (Nest_Depth)))))); 1080 end if; 1081 1082 Analyze_And_Resolve (N, Id_Kind); 1083 end Caller; 1084 1085 ------------- 1086 -- Compose -- 1087 ------------- 1088 1089 -- Transforms 'Compose into a call to the floating-point attribute 1090 -- function Compose in Fat_xxx (where xxx is the root type) 1091 1092 -- Note: we strictly should have special code here to deal with the 1093 -- case of absurdly negative arguments (less than Integer'First) 1094 -- which will return a (signed) zero value, but it hardly seems 1095 -- worth the effort. Absurdly large positive arguments will raise 1096 -- constraint error which is fine. 1097 1098 when Attribute_Compose => 1099 Expand_Fpt_Attribute_RI (N); 1100 1101 ----------------- 1102 -- Constrained -- 1103 ----------------- 1104 1105 when Attribute_Constrained => Constrained : declare 1106 Formal_Ent : constant Entity_Id := Param_Entity (Pref); 1107 1108 begin 1109 -- Reference to a parameter where the value is passed as an extra 1110 -- actual, corresponding to the extra formal referenced by the 1111 -- Extra_Constrained field of the corresponding formal. If this 1112 -- is an entry in-parameter, it is replaced by a constant renaming 1113 -- for which Extra_Constrained is never created. 1114 1115 if Present (Formal_Ent) 1116 and then Ekind (Formal_Ent) /= E_Constant 1117 and then Present (Extra_Constrained (Formal_Ent)) 1118 then 1119 Rewrite (N, 1120 New_Occurrence_Of 1121 (Extra_Constrained (Formal_Ent), Sloc (N))); 1122 1123 -- For variables with a Extra_Constrained field, we use the 1124 -- corresponding entity. 1125 1126 elsif Nkind (Pref) = N_Identifier 1127 and then Ekind (Entity (Pref)) = E_Variable 1128 and then Present (Extra_Constrained (Entity (Pref))) 1129 then 1130 Rewrite (N, 1131 New_Occurrence_Of 1132 (Extra_Constrained (Entity (Pref)), Sloc (N))); 1133 1134 -- For all other entity names, we can tell at compile time 1135 1136 elsif Is_Entity_Name (Pref) then 1137 declare 1138 Ent : constant Entity_Id := Entity (Pref); 1139 Res : Boolean; 1140 1141 begin 1142 -- (RM J.4) obsolescent cases 1143 1144 if Is_Type (Ent) then 1145 1146 -- Private type 1147 1148 if Is_Private_Type (Ent) then 1149 Res := not Has_Discriminants (Ent) 1150 or else Is_Constrained (Ent); 1151 1152 -- It not a private type, must be a generic actual type 1153 -- that corresponded to a private type. We know that this 1154 -- correspondence holds, since otherwise the reference 1155 -- within the generic template would have been illegal. 1156 1157 else 1158 if Is_Composite_Type (Underlying_Type (Ent)) then 1159 Res := Is_Constrained (Ent); 1160 else 1161 Res := True; 1162 end if; 1163 end if; 1164 1165 -- If the prefix is not a variable or is aliased, then 1166 -- definitely true; if it's a formal parameter without 1167 -- an associated extra formal, then treat it as constrained. 1168 1169 elsif not Is_Variable (Pref) 1170 or else Present (Formal_Ent) 1171 or else Is_Aliased_View (Pref) 1172 then 1173 Res := True; 1174 1175 -- Variable case, just look at type to see if it is 1176 -- constrained. Note that the one case where this is 1177 -- not accurate (the procedure formal case), has been 1178 -- handled above. 1179 1180 else 1181 Res := Is_Constrained (Etype (Ent)); 1182 end if; 1183 1184 if Res then 1185 Rewrite (N, 1186 New_Reference_To (Standard_True, Loc)); 1187 else 1188 Rewrite (N, 1189 New_Reference_To (Standard_False, Loc)); 1190 end if; 1191 end; 1192 1193 -- Prefix is not an entity name. These are also cases where 1194 -- we can always tell at compile time by looking at the form 1195 -- and type of the prefix. 1196 1197 else 1198 if not Is_Variable (Pref) 1199 or else Nkind (Pref) = N_Explicit_Dereference 1200 or else Is_Constrained (Etype (Pref)) 1201 then 1202 Rewrite (N, 1203 New_Reference_To (Standard_True, Loc)); 1204 else 1205 Rewrite (N, 1206 New_Reference_To (Standard_False, Loc)); 1207 end if; 1208 end if; 1209 1210 Analyze_And_Resolve (N, Standard_Boolean); 1211 end Constrained; 1212 1213 --------------- 1214 -- Copy_Sign -- 1215 --------------- 1216 1217 -- Transforms 'Copy_Sign into a call to the floating-point attribute 1218 -- function Copy_Sign in Fat_xxx (where xxx is the root type) 1219 1220 when Attribute_Copy_Sign => 1221 Expand_Fpt_Attribute_RR (N); 1222 1223 ----------- 1224 -- Count -- 1225 ----------- 1226 1227 -- Transforms 'Count attribute into a call to the Count function 1228 1229 when Attribute_Count => Count : 1230 declare 1231 Entnam : Node_Id; 1232 Index : Node_Id; 1233 Name : Node_Id; 1234 Call : Node_Id; 1235 Conctyp : Entity_Id; 1236 1237 begin 1238 -- If the prefix is a member of an entry family, retrieve both 1239 -- entry name and index. For a simple entry there is no index. 1240 1241 if Nkind (Pref) = N_Indexed_Component then 1242 Entnam := Prefix (Pref); 1243 Index := First (Expressions (Pref)); 1244 else 1245 Entnam := Pref; 1246 Index := Empty; 1247 end if; 1248 1249 -- Find the concurrent type in which this attribute is referenced 1250 -- (there had better be one). 1251 1252 Conctyp := Current_Scope; 1253 while not Is_Concurrent_Type (Conctyp) loop 1254 Conctyp := Scope (Conctyp); 1255 end loop; 1256 1257 -- Protected case 1258 1259 if Is_Protected_Type (Conctyp) then 1260 1261 if Abort_Allowed 1262 or else Restrictions (No_Entry_Queue) = False 1263 or else Number_Entries (Conctyp) > 1 1264 then 1265 Name := New_Reference_To (RTE (RE_Protected_Count), Loc); 1266 1267 Call := 1268 Make_Function_Call (Loc, 1269 Name => Name, 1270 Parameter_Associations => New_List ( 1271 New_Reference_To ( 1272 Object_Ref ( 1273 Corresponding_Body (Parent (Conctyp))), Loc), 1274 Entry_Index_Expression ( 1275 Loc, Entity (Entnam), Index, Scope (Entity (Entnam))))); 1276 else 1277 Name := New_Reference_To (RTE (RE_Protected_Count_Entry), Loc); 1278 1279 Call := Make_Function_Call (Loc, 1280 Name => Name, 1281 Parameter_Associations => New_List ( 1282 New_Reference_To ( 1283 Object_Ref ( 1284 Corresponding_Body (Parent (Conctyp))), Loc))); 1285 end if; 1286 1287 -- Task case 1288 1289 else 1290 Call := 1291 Make_Function_Call (Loc, 1292 Name => New_Reference_To (RTE (RE_Task_Count), Loc), 1293 Parameter_Associations => New_List ( 1294 Entry_Index_Expression 1295 (Loc, Entity (Entnam), Index, Scope (Entity (Entnam))))); 1296 end if; 1297 1298 -- The call returns type Natural but the context is universal integer 1299 -- so any integer type is allowed. The attribute was already resolved 1300 -- so its Etype is the required result type. If the base type of the 1301 -- context type is other than Standard.Integer we put in a conversion 1302 -- to the required type. This can be a normal typed conversion since 1303 -- both input and output types of the conversion are integer types 1304 1305 if Base_Type (Typ) /= Base_Type (Standard_Integer) then 1306 Rewrite (N, Convert_To (Typ, Call)); 1307 else 1308 Rewrite (N, Call); 1309 end if; 1310 1311 Analyze_And_Resolve (N, Typ); 1312 end Count; 1313 1314 --------------- 1315 -- Elab_Body -- 1316 --------------- 1317 1318 -- This processing is shared by Elab_Spec 1319 1320 -- What we do is to insert the following declarations 1321 1322 -- procedure tnn; 1323 -- pragma Import (C, enn, "name___elabb/s"); 1324 1325 -- and then the Elab_Body/Spec attribute is replaced by a reference 1326 -- to this defining identifier. 1327 1328 when Attribute_Elab_Body | 1329 Attribute_Elab_Spec => 1330 1331 Elab_Body : declare 1332 Ent : constant Entity_Id := 1333 Make_Defining_Identifier (Loc, 1334 New_Internal_Name ('E')); 1335 Str : String_Id; 1336 Lang : Node_Id; 1337 1338 procedure Make_Elab_String (Nod : Node_Id); 1339 -- Given Nod, an identifier, or a selected component, put the 1340 -- image into the current string literal, with double underline 1341 -- between components. 1342 1343 procedure Make_Elab_String (Nod : Node_Id) is 1344 begin 1345 if Nkind (Nod) = N_Selected_Component then 1346 Make_Elab_String (Prefix (Nod)); 1347 if Java_VM then 1348 Store_String_Char ('$'); 1349 else 1350 Store_String_Char ('_'); 1351 Store_String_Char ('_'); 1352 end if; 1353 1354 Get_Name_String (Chars (Selector_Name (Nod))); 1355 1356 else 1357 pragma Assert (Nkind (Nod) = N_Identifier); 1358 Get_Name_String (Chars (Nod)); 1359 end if; 1360 1361 Store_String_Chars (Name_Buffer (1 .. Name_Len)); 1362 end Make_Elab_String; 1363 1364 -- Start of processing for Elab_Body/Elab_Spec 1365 1366 begin 1367 -- First we need to prepare the string literal for the name of 1368 -- the elaboration routine to be referenced. 1369 1370 Start_String; 1371 Make_Elab_String (Pref); 1372 1373 if Java_VM then 1374 Store_String_Chars ("._elab"); 1375 Lang := Make_Identifier (Loc, Name_Ada); 1376 else 1377 Store_String_Chars ("___elab"); 1378 Lang := Make_Identifier (Loc, Name_C); 1379 end if; 1380 1381 if Id = Attribute_Elab_Body then 1382 Store_String_Char ('b'); 1383 else 1384 Store_String_Char ('s'); 1385 end if; 1386 1387 Str := End_String; 1388 1389 Insert_Actions (N, New_List ( 1390 Make_Subprogram_Declaration (Loc, 1391 Specification => 1392 Make_Procedure_Specification (Loc, 1393 Defining_Unit_Name => Ent)), 1394 1395 Make_Pragma (Loc, 1396 Chars => Name_Import, 1397 Pragma_Argument_Associations => New_List ( 1398 Make_Pragma_Argument_Association (Loc, 1399 Expression => Lang), 1400 1401 Make_Pragma_Argument_Association (Loc, 1402 Expression => 1403 Make_Identifier (Loc, Chars (Ent))), 1404 1405 Make_Pragma_Argument_Association (Loc, 1406 Expression => 1407 Make_String_Literal (Loc, Str)))))); 1408 1409 Set_Entity (N, Ent); 1410 Rewrite (N, New_Occurrence_Of (Ent, Loc)); 1411 end Elab_Body; 1412 1413 ---------------- 1414 -- Elaborated -- 1415 ---------------- 1416 1417 -- Elaborated is always True for preelaborated units, predefined 1418 -- units, pure units and units which have Elaborate_Body pragmas. 1419 -- These units have no elaboration entity. 1420 1421 -- Note: The Elaborated attribute is never passed through to Gigi 1422 1423 when Attribute_Elaborated => Elaborated : declare 1424 Ent : constant Entity_Id := Entity (Pref); 1425 1426 begin 1427 if Present (Elaboration_Entity (Ent)) then 1428 Rewrite (N, 1429 New_Occurrence_Of (Elaboration_Entity (Ent), Loc)); 1430 else 1431 Rewrite (N, New_Occurrence_Of (Standard_True, Loc)); 1432 end if; 1433 end Elaborated; 1434 1435 -------------- 1436 -- Enum_Rep -- 1437 -------------- 1438 1439 when Attribute_Enum_Rep => Enum_Rep : 1440 begin 1441 -- X'Enum_Rep (Y) expands to 1442 1443 -- target-type (Y) 1444 1445 -- This is simply a direct conversion from the enumeration type 1446 -- to the target integer type, which is treated by Gigi as a normal 1447 -- integer conversion, treating the enumeration type as an integer, 1448 -- which is exactly what we want! We set Conversion_OK to make sure 1449 -- that the analyzer does not complain about what otherwise might 1450 -- be an illegal conversion. 1451 1452 if Is_Non_Empty_List (Exprs) then 1453 Rewrite (N, 1454 OK_Convert_To (Typ, Relocate_Node (First (Exprs)))); 1455 1456 -- X'Enum_Rep where X is an enumeration literal is replaced by 1457 -- the literal value. 1458 1459 elsif Ekind (Entity (Pref)) = E_Enumeration_Literal then 1460 Rewrite (N, 1461 Make_Integer_Literal (Loc, Enumeration_Rep (Entity (Pref)))); 1462 1463 -- If this is a renaming of a literal, recover the representation 1464 -- of the original. 1465 1466 elsif Ekind (Entity (Pref)) = E_Constant 1467 and then Present (Renamed_Object (Entity (Pref))) 1468 and then 1469 Ekind (Entity (Renamed_Object (Entity (Pref)))) 1470 = E_Enumeration_Literal 1471 then 1472 Rewrite (N, 1473 Make_Integer_Literal (Loc, 1474 Enumeration_Rep (Entity (Renamed_Object (Entity (Pref)))))); 1475 1476 -- X'Enum_Rep where X is an object does a direct unchecked conversion 1477 -- of the object value, as described for the type case above. 1478 1479 else 1480 Rewrite (N, 1481 OK_Convert_To (Typ, Relocate_Node (Pref))); 1482 end if; 1483 1484 Set_Etype (N, Typ); 1485 Analyze_And_Resolve (N, Typ); 1486 1487 end Enum_Rep; 1488 1489 -------------- 1490 -- Exponent -- 1491 -------------- 1492 1493 -- Transforms 'Exponent into a call to the floating-point attribute 1494 -- function Exponent in Fat_xxx (where xxx is the root type) 1495 1496 when Attribute_Exponent => 1497 Expand_Fpt_Attribute_R (N); 1498 1499 ------------------ 1500 -- External_Tag -- 1501 ------------------ 1502 1503 -- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag) 1504 1505 when Attribute_External_Tag => External_Tag : 1506 begin 1507 Rewrite (N, 1508 Make_Function_Call (Loc, 1509 Name => New_Reference_To (RTE (RE_External_Tag), Loc), 1510 Parameter_Associations => New_List ( 1511 Make_Attribute_Reference (Loc, 1512 Attribute_Name => Name_Tag, 1513 Prefix => Prefix (N))))); 1514 1515 Analyze_And_Resolve (N, Standard_String); 1516 end External_Tag; 1517 1518 ----------- 1519 -- First -- 1520 ----------- 1521 1522 when Attribute_First => declare 1523 Ptyp : constant Entity_Id := Etype (Pref); 1524 1525 begin 1526 -- If the prefix type is a constrained packed array type which 1527 -- already has a Packed_Array_Type representation defined, then 1528 -- replace this attribute with a direct reference to 'First of the 1529 -- appropriate index subtype (since otherwise Gigi will try to give 1530 -- us the value of 'First for this implementation type). 1531 1532 if Is_Constrained_Packed_Array (Ptyp) then 1533 Rewrite (N, 1534 Make_Attribute_Reference (Loc, 1535 Attribute_Name => Name_First, 1536 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc))); 1537 Analyze_And_Resolve (N, Typ); 1538 1539 elsif Is_Access_Type (Ptyp) then 1540 Apply_Access_Check (N); 1541 end if; 1542 end; 1543 1544 --------------- 1545 -- First_Bit -- 1546 --------------- 1547 1548 -- We compute this if a component clause was present, otherwise 1549 -- we leave the computation up to Gigi, since we don't know what 1550 -- layout will be chosen. 1551 1552 when Attribute_First_Bit => First_Bit : 1553 declare 1554 CE : constant Entity_Id := Entity (Selector_Name (Pref)); 1555 1556 begin 1557 if Known_Static_Component_Bit_Offset (CE) then 1558 Rewrite (N, 1559 Make_Integer_Literal (Loc, 1560 Component_Bit_Offset (CE) mod System_Storage_Unit)); 1561 1562 Analyze_And_Resolve (N, Typ); 1563 1564 else 1565 Apply_Universal_Integer_Attribute_Checks (N); 1566 end if; 1567 end First_Bit; 1568 1569 ----------------- 1570 -- Fixed_Value -- 1571 ----------------- 1572 1573 -- We transform: 1574 1575 -- fixtype'Fixed_Value (integer-value) 1576 1577 -- into 1578 1579 -- fixtype(integer-value) 1580 1581 -- we do all the required analysis of the conversion here, because 1582 -- we do not want this to go through the fixed-point conversion 1583 -- circuits. Note that gigi always treats fixed-point as equivalent 1584 -- to the corresponding integer type anyway. 1585 1586 when Attribute_Fixed_Value => Fixed_Value : 1587 begin 1588 Rewrite (N, 1589 Make_Type_Conversion (Loc, 1590 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc), 1591 Expression => Relocate_Node (First (Exprs)))); 1592 Set_Etype (N, Entity (Pref)); 1593 Set_Analyzed (N); 1594 1595 -- Note: it might appear that a properly analyzed unchecked conversion 1596 -- would be just fine here, but that's not the case, since the full 1597 -- range checks performed by the following call are critical! 1598 1599 Apply_Type_Conversion_Checks (N); 1600 end Fixed_Value; 1601 1602 ----------- 1603 -- Floor -- 1604 ----------- 1605 1606 -- Transforms 'Floor into a call to the floating-point attribute 1607 -- function Floor in Fat_xxx (where xxx is the root type) 1608 1609 when Attribute_Floor => 1610 Expand_Fpt_Attribute_R (N); 1611 1612 ---------- 1613 -- Fore -- 1614 ---------- 1615 1616 -- For the fixed-point type Typ: 1617 1618 -- Typ'Fore 1619 1620 -- expands into 1621 1622 -- Result_Type (System.Fore (Long_Long_Float (Type'First)), 1623 -- Long_Long_Float (Type'Last)) 1624 1625 -- Note that we know that the type is a non-static subtype, or Fore 1626 -- would have itself been computed dynamically in Eval_Attribute. 1627 1628 when Attribute_Fore => Fore : 1629 declare 1630 Ptyp : constant Entity_Id := Etype (Pref); 1631 1632 begin 1633 Rewrite (N, 1634 Convert_To (Typ, 1635 Make_Function_Call (Loc, 1636 Name => New_Reference_To (RTE (RE_Fore), Loc), 1637 1638 Parameter_Associations => New_List ( 1639 Convert_To (Standard_Long_Long_Float, 1640 Make_Attribute_Reference (Loc, 1641 Prefix => New_Reference_To (Ptyp, Loc), 1642 Attribute_Name => Name_First)), 1643 1644 Convert_To (Standard_Long_Long_Float, 1645 Make_Attribute_Reference (Loc, 1646 Prefix => New_Reference_To (Ptyp, Loc), 1647 Attribute_Name => Name_Last)))))); 1648 1649 Analyze_And_Resolve (N, Typ); 1650 end Fore; 1651 1652 -------------- 1653 -- Fraction -- 1654 -------------- 1655 1656 -- Transforms 'Fraction into a call to the floating-point attribute 1657 -- function Fraction in Fat_xxx (where xxx is the root type) 1658 1659 when Attribute_Fraction => 1660 Expand_Fpt_Attribute_R (N); 1661 1662 -------------- 1663 -- Identity -- 1664 -------------- 1665 1666 -- For an exception returns a reference to the exception data: 1667 -- Exception_Id!(Prefix'Reference) 1668 1669 -- For a task it returns a reference to the _task_id component of 1670 -- corresponding record: 1671 1672 -- taskV!(Prefix)._Task_Id, converted to the type Task_ID defined 1673 1674 -- in Ada.Task_Identification. 1675 1676 when Attribute_Identity => Identity : declare 1677 Id_Kind : Entity_Id; 1678 1679 begin 1680 if Etype (Pref) = Standard_Exception_Type then 1681 Id_Kind := RTE (RE_Exception_Id); 1682 1683 if Present (Renamed_Object (Entity (Pref))) then 1684 Set_Entity (Pref, Renamed_Object (Entity (Pref))); 1685 end if; 1686 1687 Rewrite (N, 1688 Unchecked_Convert_To (Id_Kind, Make_Reference (Loc, Pref))); 1689 else 1690 Id_Kind := RTE (RO_AT_Task_ID); 1691 1692 Rewrite (N, 1693 Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref))); 1694 end if; 1695 1696 Analyze_And_Resolve (N, Id_Kind); 1697 end Identity; 1698 1699 ----------- 1700 -- Image -- 1701 ----------- 1702 1703 -- Image attribute is handled in separate unit Exp_Imgv 1704 1705 when Attribute_Image => 1706 Exp_Imgv.Expand_Image_Attribute (N); 1707 1708 --------- 1709 -- Img -- 1710 --------- 1711 1712 -- X'Img is expanded to typ'Image (X), where typ is the type of X 1713 1714 when Attribute_Img => Img : 1715 begin 1716 Rewrite (N, 1717 Make_Attribute_Reference (Loc, 1718 Prefix => New_Reference_To (Etype (Pref), Loc), 1719 Attribute_Name => Name_Image, 1720 Expressions => New_List (Relocate_Node (Pref)))); 1721 1722 Analyze_And_Resolve (N, Standard_String); 1723 end Img; 1724 1725 ----------- 1726 -- Input -- 1727 ----------- 1728 1729 when Attribute_Input => Input : declare 1730 P_Type : constant Entity_Id := Entity (Pref); 1731 B_Type : constant Entity_Id := Base_Type (P_Type); 1732 U_Type : constant Entity_Id := Underlying_Type (P_Type); 1733 Strm : constant Node_Id := First (Exprs); 1734 Fname : Entity_Id; 1735 Decl : Node_Id; 1736 Call : Node_Id; 1737 Prag : Node_Id; 1738 Arg2 : Node_Id; 1739 Rfunc : Node_Id; 1740 1741 Cntrl : Node_Id := Empty; 1742 -- Value for controlling argument in call. Always Empty except in 1743 -- the dispatching (class-wide type) case, where it is a reference 1744 -- to the dummy object initialized to the right internal tag. 1745 1746 begin 1747 -- If no underlying type, we have an error that will be diagnosed 1748 -- elsewhere, so here we just completely ignore the expansion. 1749 1750 if No (U_Type) then 1751 return; 1752 end if; 1753 1754 -- If there is a TSS for Input, just call it 1755 1756 Fname := Find_Stream_Subprogram (P_Type, TSS_Stream_Input); 1757 1758 if Present (Fname) then 1759 null; 1760 1761 else 1762 -- If there is a Stream_Convert pragma, use it, we rewrite 1763 1764 -- sourcetyp'Input (stream) 1765 1766 -- as 1767 1768 -- sourcetyp (streamread (strmtyp'Input (stream))); 1769 1770 -- where stmrearead is the given Read function that converts 1771 -- an argument of type strmtyp to type sourcetyp or a type 1772 -- from which it is derived. The extra conversion is required 1773 -- for the derived case. 1774 1775 Prag := 1776 Get_Rep_Pragma 1777 (Implementation_Base_Type (P_Type), Name_Stream_Convert); 1778 1779 if Present (Prag) then 1780 Arg2 := Next (First (Pragma_Argument_Associations (Prag))); 1781 Rfunc := Entity (Expression (Arg2)); 1782 1783 Rewrite (N, 1784 Convert_To (B_Type, 1785 Make_Function_Call (Loc, 1786 Name => New_Occurrence_Of (Rfunc, Loc), 1787 Parameter_Associations => New_List ( 1788 Make_Attribute_Reference (Loc, 1789 Prefix => 1790 New_Occurrence_Of 1791 (Etype (First_Formal (Rfunc)), Loc), 1792 Attribute_Name => Name_Input, 1793 Expressions => Exprs))))); 1794 1795 Analyze_And_Resolve (N, B_Type); 1796 return; 1797 1798 -- Elementary types 1799 1800 elsif Is_Elementary_Type (U_Type) then 1801 1802 -- A special case arises if we have a defined _Read routine, 1803 -- since in this case we are required to call this routine. 1804 1805 if Present (TSS (Base_Type (U_Type), TSS_Stream_Read)) then 1806 Build_Record_Or_Elementary_Input_Function 1807 (Loc, U_Type, Decl, Fname); 1808 Insert_Action (N, Decl); 1809 1810 -- For normal cases, we call the I_xxx routine directly 1811 1812 else 1813 Rewrite (N, Build_Elementary_Input_Call (N)); 1814 Analyze_And_Resolve (N, P_Type); 1815 return; 1816 end if; 1817 1818 -- Array type case 1819 1820 elsif Is_Array_Type (U_Type) then 1821 Build_Array_Input_Function (Loc, U_Type, Decl, Fname); 1822 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False); 1823 1824 -- Dispatching case with class-wide type 1825 1826 elsif Is_Class_Wide_Type (P_Type) then 1827 1828 declare 1829 Rtyp : constant Entity_Id := Root_Type (P_Type); 1830 Dnn : Entity_Id; 1831 Decl : Node_Id; 1832 1833 begin 1834 -- Read the internal tag (RM 13.13.2(34)) and use it to 1835 -- initialize a dummy tag object: 1836 1837 -- Dnn : Ada.Tags.Tag 1838 -- := Internal_Tag (String'Input (Strm)); 1839 1840 -- This dummy object is used only to provide a controlling 1841 -- argument for the eventual _Input call. 1842 1843 Dnn := 1844 Make_Defining_Identifier (Loc, 1845 Chars => New_Internal_Name ('D')); 1846 1847 Decl := 1848 Make_Object_Declaration (Loc, 1849 Defining_Identifier => Dnn, 1850 Object_Definition => 1851 New_Occurrence_Of (RTE (RE_Tag), Loc), 1852 Expression => 1853 Make_Function_Call (Loc, 1854 Name => 1855 New_Occurrence_Of (RTE (RE_Internal_Tag), Loc), 1856 Parameter_Associations => New_List ( 1857 Make_Attribute_Reference (Loc, 1858 Prefix => 1859 New_Occurrence_Of (Standard_String, Loc), 1860 Attribute_Name => Name_Input, 1861 Expressions => New_List ( 1862 Relocate_Node 1863 (Duplicate_Subexpr (Strm))))))); 1864 1865 Insert_Action (N, Decl); 1866 1867 -- Now we need to get the entity for the call, and construct 1868 -- a function call node, where we preset a reference to Dnn 1869 -- as the controlling argument (doing an unchecked 1870 -- conversion to the classwide tagged type to make it 1871 -- look like a real tagged object). 1872 1873 Fname := Find_Prim_Op (Rtyp, TSS_Stream_Input); 1874 Cntrl := Unchecked_Convert_To (P_Type, 1875 New_Occurrence_Of (Dnn, Loc)); 1876 Set_Etype (Cntrl, P_Type); 1877 Set_Parent (Cntrl, N); 1878 end; 1879 1880 -- For tagged types, use the primitive Input function 1881 1882 elsif Is_Tagged_Type (U_Type) then 1883 Fname := Find_Prim_Op (U_Type, TSS_Stream_Input); 1884 1885 -- All other record type cases, including protected records. 1886 -- The latter only arise for expander generated code for 1887 -- handling shared passive partition access. 1888 1889 else 1890 pragma Assert 1891 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type)); 1892 1893 Build_Record_Or_Elementary_Input_Function 1894 (Loc, Base_Type (U_Type), Decl, Fname); 1895 Insert_Action (N, Decl); 1896 end if; 1897 end if; 1898 1899 -- If we fall through, Fname is the function to be called. The 1900 -- result is obtained by calling the appropriate function, then 1901 -- converting the result. The conversion does a subtype check. 1902 1903 Call := 1904 Make_Function_Call (Loc, 1905 Name => New_Occurrence_Of (Fname, Loc), 1906 Parameter_Associations => New_List ( 1907 Relocate_Node (Strm))); 1908 1909 Set_Controlling_Argument (Call, Cntrl); 1910 Rewrite (N, Unchecked_Convert_To (P_Type, Call)); 1911 Analyze_And_Resolve (N, P_Type); 1912 end Input; 1913 1914 ------------------- 1915 -- Integer_Value -- 1916 ------------------- 1917 1918 -- We transform 1919 1920 -- inttype'Fixed_Value (fixed-value) 1921 1922 -- into 1923 1924 -- inttype(integer-value)) 1925 1926 -- we do all the required analysis of the conversion here, because 1927 -- we do not want this to go through the fixed-point conversion 1928 -- circuits. Note that gigi always treats fixed-point as equivalent 1929 -- to the corresponding integer type anyway. 1930 1931 when Attribute_Integer_Value => Integer_Value : 1932 begin 1933 Rewrite (N, 1934 Make_Type_Conversion (Loc, 1935 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc), 1936 Expression => Relocate_Node (First (Exprs)))); 1937 Set_Etype (N, Entity (Pref)); 1938 Set_Analyzed (N); 1939 1940 -- Note: it might appear that a properly analyzed unchecked conversion 1941 -- would be just fine here, but that's not the case, since the full 1942 -- range checks performed by the following call are critical! 1943 1944 Apply_Type_Conversion_Checks (N); 1945 end Integer_Value; 1946 1947 ---------- 1948 -- Last -- 1949 ---------- 1950 1951 when Attribute_Last => declare 1952 Ptyp : constant Entity_Id := Etype (Pref); 1953 1954 begin 1955 -- If the prefix type is a constrained packed array type which 1956 -- already has a Packed_Array_Type representation defined, then 1957 -- replace this attribute with a direct reference to 'Last of the 1958 -- appropriate index subtype (since otherwise Gigi will try to give 1959 -- us the value of 'Last for this implementation type). 1960 1961 if Is_Constrained_Packed_Array (Ptyp) then 1962 Rewrite (N, 1963 Make_Attribute_Reference (Loc, 1964 Attribute_Name => Name_Last, 1965 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc))); 1966 Analyze_And_Resolve (N, Typ); 1967 1968 elsif Is_Access_Type (Ptyp) then 1969 Apply_Access_Check (N); 1970 end if; 1971 end; 1972 1973 -------------- 1974 -- Last_Bit -- 1975 -------------- 1976 1977 -- We compute this if a component clause was present, otherwise 1978 -- we leave the computation up to Gigi, since we don't know what 1979 -- layout will be chosen. 1980 1981 when Attribute_Last_Bit => Last_Bit : 1982 declare 1983 CE : constant Entity_Id := Entity (Selector_Name (Pref)); 1984 1985 begin 1986 if Known_Static_Component_Bit_Offset (CE) 1987 and then Known_Static_Esize (CE) 1988 then 1989 Rewrite (N, 1990 Make_Integer_Literal (Loc, 1991 Intval => (Component_Bit_Offset (CE) mod System_Storage_Unit) 1992 + Esize (CE) - 1)); 1993 1994 Analyze_And_Resolve (N, Typ); 1995 1996 else 1997 Apply_Universal_Integer_Attribute_Checks (N); 1998 end if; 1999 end Last_Bit; 2000 2001 ------------------ 2002 -- Leading_Part -- 2003 ------------------ 2004 2005 -- Transforms 'Leading_Part into a call to the floating-point attribute 2006 -- function Leading_Part in Fat_xxx (where xxx is the root type) 2007 2008 -- Note: strictly, we should have special case code to deal with 2009 -- absurdly large positive arguments (greater than Integer'Last), 2010 -- which result in returning the first argument unchanged, but it 2011 -- hardly seems worth the effort. We raise constraint error for 2012 -- absurdly negative arguments which is fine. 2013 2014 when Attribute_Leading_Part => 2015 Expand_Fpt_Attribute_RI (N); 2016 2017 ------------ 2018 -- Length -- 2019 ------------ 2020 2021 when Attribute_Length => declare 2022 Ptyp : constant Entity_Id := Etype (Pref); 2023 Ityp : Entity_Id; 2024 Xnum : Uint; 2025 2026 begin 2027 -- Processing for packed array types 2028 2029 if Is_Array_Type (Ptyp) and then Is_Packed (Ptyp) then 2030 Ityp := Get_Index_Subtype (N); 2031 2032 -- If the index type, Ityp, is an enumeration type with 2033 -- holes, then we calculate X'Length explicitly using 2034 2035 -- Typ'Max 2036 -- (0, Ityp'Pos (X'Last (N)) - 2037 -- Ityp'Pos (X'First (N)) + 1); 2038 2039 -- Since the bounds in the template are the representation 2040 -- values and gigi would get the wrong value. 2041 2042 if Is_Enumeration_Type (Ityp) 2043 and then Present (Enum_Pos_To_Rep (Base_Type (Ityp))) 2044 then 2045 if No (Exprs) then 2046 Xnum := Uint_1; 2047 else 2048 Xnum := Expr_Value (First (Expressions (N))); 2049 end if; 2050 2051 Rewrite (N, 2052 Make_Attribute_Reference (Loc, 2053 Prefix => New_Occurrence_Of (Typ, Loc), 2054 Attribute_Name => Name_Max, 2055 Expressions => New_List 2056 (Make_Integer_Literal (Loc, 0), 2057 2058 Make_Op_Add (Loc, 2059 Left_Opnd => 2060 Make_Op_Subtract (Loc, 2061 Left_Opnd => 2062 Make_Attribute_Reference (Loc, 2063 Prefix => New_Occurrence_Of (Ityp, Loc), 2064 Attribute_Name => Name_Pos, 2065 2066 Expressions => New_List ( 2067 Make_Attribute_Reference (Loc, 2068 Prefix => Duplicate_Subexpr (Pref), 2069 Attribute_Name => Name_Last, 2070 Expressions => New_List ( 2071 Make_Integer_Literal (Loc, Xnum))))), 2072 2073 Right_Opnd => 2074 Make_Attribute_Reference (Loc, 2075 Prefix => New_Occurrence_Of (Ityp, Loc), 2076 Attribute_Name => Name_Pos, 2077 2078 Expressions => New_List ( 2079 Make_Attribute_Reference (Loc, 2080 Prefix => 2081 Duplicate_Subexpr_No_Checks (Pref), 2082 Attribute_Name => Name_First, 2083 Expressions => New_List ( 2084 Make_Integer_Literal (Loc, Xnum)))))), 2085 2086 Right_Opnd => Make_Integer_Literal (Loc, 1))))); 2087 2088 Analyze_And_Resolve (N, Typ, Suppress => All_Checks); 2089 return; 2090 2091 -- If the prefix type is a constrained packed array type which 2092 -- already has a Packed_Array_Type representation defined, then 2093 -- replace this attribute with a direct reference to 'Range_Length 2094 -- of the appropriate index subtype (since otherwise Gigi will try 2095 -- to give us the value of 'Length for this implementation type). 2096 2097 elsif Is_Constrained (Ptyp) then 2098 Rewrite (N, 2099 Make_Attribute_Reference (Loc, 2100 Attribute_Name => Name_Range_Length, 2101 Prefix => New_Reference_To (Ityp, Loc))); 2102 Analyze_And_Resolve (N, Typ); 2103 end if; 2104 2105 -- If we have a packed array that is not bit packed, which was 2106 2107 -- Access type case 2108 2109 elsif Is_Access_Type (Ptyp) then 2110 Apply_Access_Check (N); 2111 2112 -- If the designated type is a packed array type, then we 2113 -- convert the reference to: 2114 2115 -- typ'Max (0, 1 + 2116 -- xtyp'Pos (Pref'Last (Expr)) - 2117 -- xtyp'Pos (Pref'First (Expr))); 2118 2119 -- This is a bit complex, but it is the easiest thing to do 2120 -- that works in all cases including enum types with holes 2121 -- xtyp here is the appropriate index type. 2122 2123 declare 2124 Dtyp : constant Entity_Id := Designated_Type (Ptyp); 2125 Xtyp : Entity_Id; 2126 2127 begin 2128 if Is_Array_Type (Dtyp) and then Is_Packed (Dtyp) then 2129 Xtyp := Get_Index_Subtype (N); 2130 2131 Rewrite (N, 2132 Make_Attribute_Reference (Loc, 2133 Prefix => New_Occurrence_Of (Typ, Loc), 2134 Attribute_Name => Name_Max, 2135 Expressions => New_List ( 2136 Make_Integer_Literal (Loc, 0), 2137 2138 Make_Op_Add (Loc, 2139 Make_Integer_Literal (Loc, 1), 2140 Make_Op_Subtract (Loc, 2141 Left_Opnd => 2142 Make_Attribute_Reference (Loc, 2143 Prefix => New_Occurrence_Of (Xtyp, Loc), 2144 Attribute_Name => Name_Pos, 2145 Expressions => New_List ( 2146 Make_Attribute_Reference (Loc, 2147 Prefix => Duplicate_Subexpr (Pref), 2148 Attribute_Name => Name_Last, 2149 Expressions => 2150 New_Copy_List (Exprs)))), 2151 2152 Right_Opnd => 2153 Make_Attribute_Reference (Loc, 2154 Prefix => New_Occurrence_Of (Xtyp, Loc), 2155 Attribute_Name => Name_Pos, 2156 Expressions => New_List ( 2157 Make_Attribute_Reference (Loc, 2158 Prefix => 2159 Duplicate_Subexpr_No_Checks (Pref), 2160 Attribute_Name => Name_First, 2161 Expressions => 2162 New_Copy_List (Exprs))))))))); 2163 2164 Analyze_And_Resolve (N, Typ); 2165 end if; 2166 end; 2167 2168 -- Otherwise leave it to gigi 2169 2170 else 2171 Apply_Universal_Integer_Attribute_Checks (N); 2172 end if; 2173 end; 2174 2175 ------------- 2176 -- Machine -- 2177 ------------- 2178 2179 -- Transforms 'Machine into a call to the floating-point attribute 2180 -- function Machine in Fat_xxx (where xxx is the root type) 2181 2182 when Attribute_Machine => 2183 Expand_Fpt_Attribute_R (N); 2184 2185 ------------------ 2186 -- Machine_Size -- 2187 ------------------ 2188 2189 -- Machine_Size is equivalent to Object_Size, so transform it into 2190 -- Object_Size and that way Gigi never sees Machine_Size. 2191 2192 when Attribute_Machine_Size => 2193 Rewrite (N, 2194 Make_Attribute_Reference (Loc, 2195 Prefix => Prefix (N), 2196 Attribute_Name => Name_Object_Size)); 2197 2198 Analyze_And_Resolve (N, Typ); 2199 2200 -------------- 2201 -- Mantissa -- 2202 -------------- 2203 2204 -- The only case that can get this far is the dynamic case of the 2205 -- old Ada 83 Mantissa attribute for the fixed-point case. For this 2206 -- case, we expand: 2207 2208 -- typ'Mantissa 2209 2210 -- into 2211 2212 -- ityp (System.Mantissa.Mantissa_Value 2213 -- (Integer'Integer_Value (typ'First), 2214 -- Integer'Integer_Value (typ'Last))); 2215 2216 when Attribute_Mantissa => Mantissa : declare 2217 Ptyp : constant Entity_Id := Etype (Pref); 2218 2219 begin 2220 Rewrite (N, 2221 Convert_To (Typ, 2222 Make_Function_Call (Loc, 2223 Name => New_Occurrence_Of (RTE (RE_Mantissa_Value), Loc), 2224 2225 Parameter_Associations => New_List ( 2226 2227 Make_Attribute_Reference (Loc, 2228 Prefix => New_Occurrence_Of (Standard_Integer, Loc), 2229 Attribute_Name => Name_Integer_Value, 2230 Expressions => New_List ( 2231 2232 Make_Attribute_Reference (Loc, 2233 Prefix => New_Occurrence_Of (Ptyp, Loc), 2234 Attribute_Name => Name_First))), 2235 2236 Make_Attribute_Reference (Loc, 2237 Prefix => New_Occurrence_Of (Standard_Integer, Loc), 2238 Attribute_Name => Name_Integer_Value, 2239 Expressions => New_List ( 2240 2241 Make_Attribute_Reference (Loc, 2242 Prefix => New_Occurrence_Of (Ptyp, Loc), 2243 Attribute_Name => Name_Last))))))); 2244 2245 Analyze_And_Resolve (N, Typ); 2246 end Mantissa; 2247 2248 ----------- 2249 -- Model -- 2250 ----------- 2251 2252 -- Transforms 'Model into a call to the floating-point attribute 2253 -- function Model in Fat_xxx (where xxx is the root type) 2254 2255 when Attribute_Model => 2256 Expand_Fpt_Attribute_R (N); 2257 2258 ----------------- 2259 -- Object_Size -- 2260 ----------------- 2261 2262 -- The processing for Object_Size shares the processing for Size 2263 2264 ------------ 2265 -- Output -- 2266 ------------ 2267 2268 when Attribute_Output => Output : declare 2269 P_Type : constant Entity_Id := Entity (Pref); 2270 U_Type : constant Entity_Id := Underlying_Type (P_Type); 2271 Pname : Entity_Id; 2272 Decl : Node_Id; 2273 Prag : Node_Id; 2274 Arg3 : Node_Id; 2275 Wfunc : Node_Id; 2276 2277 begin 2278 -- If no underlying type, we have an error that will be diagnosed 2279 -- elsewhere, so here we just completely ignore the expansion. 2280 2281 if No (U_Type) then 2282 return; 2283 end if; 2284 2285 -- If TSS for Output is present, just call it 2286 2287 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Output); 2288 2289 if Present (Pname) then 2290 null; 2291 2292 else 2293 -- If there is a Stream_Convert pragma, use it, we rewrite 2294 2295 -- sourcetyp'Output (stream, Item) 2296 2297 -- as 2298 2299 -- strmtyp'Output (Stream, strmwrite (acttyp (Item))); 2300 2301 -- where strmwrite is the given Write function that converts 2302 -- an argument of type sourcetyp or a type acctyp, from which 2303 -- it is derived to type strmtyp. The conversion to acttyp is 2304 -- required for the derived case. 2305 2306 Prag := 2307 Get_Rep_Pragma 2308 (Implementation_Base_Type (P_Type), Name_Stream_Convert); 2309 2310 if Present (Prag) then 2311 Arg3 := 2312 Next (Next (First (Pragma_Argument_Associations (Prag)))); 2313 Wfunc := Entity (Expression (Arg3)); 2314 2315 Rewrite (N, 2316 Make_Attribute_Reference (Loc, 2317 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc), 2318 Attribute_Name => Name_Output, 2319 Expressions => New_List ( 2320 Relocate_Node (First (Exprs)), 2321 Make_Function_Call (Loc, 2322 Name => New_Occurrence_Of (Wfunc, Loc), 2323 Parameter_Associations => New_List ( 2324 Convert_To (Etype (First_Formal (Wfunc)), 2325 Relocate_Node (Next (First (Exprs))))))))); 2326 2327 Analyze (N); 2328 return; 2329 2330 -- For elementary types, we call the W_xxx routine directly. 2331 -- Note that the effect of Write and Output is identical for 2332 -- the case of an elementary type, since there are no 2333 -- discriminants or bounds. 2334 2335 elsif Is_Elementary_Type (U_Type) then 2336 2337 -- A special case arises if we have a defined _Write routine, 2338 -- since in this case we are required to call this routine. 2339 2340 if Present (TSS (Base_Type (U_Type), TSS_Stream_Write)) then 2341 Build_Record_Or_Elementary_Output_Procedure 2342 (Loc, U_Type, Decl, Pname); 2343 Insert_Action (N, Decl); 2344 2345 -- For normal cases, we call the W_xxx routine directly 2346 2347 else 2348 Rewrite (N, Build_Elementary_Write_Call (N)); 2349 Analyze (N); 2350 return; 2351 end if; 2352 2353 -- Array type case 2354 2355 elsif Is_Array_Type (U_Type) then 2356 Build_Array_Output_Procedure (Loc, U_Type, Decl, Pname); 2357 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False); 2358 2359 -- Class-wide case, first output external tag, then dispatch 2360 -- to the appropriate primitive Output function (RM 13.13.2(31)). 2361 2362 elsif Is_Class_Wide_Type (P_Type) then 2363 Tag_Write : declare 2364 Strm : constant Node_Id := First (Exprs); 2365 Item : constant Node_Id := Next (Strm); 2366 2367 begin 2368 -- The code is: 2369 -- String'Output (Strm, External_Tag (Item'Tag)) 2370 2371 Insert_Action (N, 2372 Make_Attribute_Reference (Loc, 2373 Prefix => New_Occurrence_Of (Standard_String, Loc), 2374 Attribute_Name => Name_Output, 2375 Expressions => New_List ( 2376 Relocate_Node (Duplicate_Subexpr (Strm)), 2377 Make_Function_Call (Loc, 2378 Name => 2379 New_Occurrence_Of (RTE (RE_External_Tag), Loc), 2380 Parameter_Associations => New_List ( 2381 Make_Attribute_Reference (Loc, 2382 Prefix => 2383 Relocate_Node 2384 (Duplicate_Subexpr (Item, Name_Req => True)), 2385 Attribute_Name => Name_Tag)))))); 2386 end Tag_Write; 2387 2388 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output); 2389 2390 -- Tagged type case, use the primitive Output function 2391 2392 elsif Is_Tagged_Type (U_Type) then 2393 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output); 2394 2395 -- All other record type cases, including protected records. 2396 -- The latter only arise for expander generated code for 2397 -- handling shared passive partition access. 2398 2399 else 2400 pragma Assert 2401 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type)); 2402 2403 Build_Record_Or_Elementary_Output_Procedure 2404 (Loc, Base_Type (U_Type), Decl, Pname); 2405 Insert_Action (N, Decl); 2406 end if; 2407 end if; 2408 2409 -- If we fall through, Pname is the name of the procedure to call 2410 2411 Rewrite_Stream_Proc_Call (Pname); 2412 end Output; 2413 2414 --------- 2415 -- Pos -- 2416 --------- 2417 2418 -- For enumeration types with a standard representation, Pos is 2419 -- handled by Gigi. 2420 2421 -- For enumeration types, with a non-standard representation we 2422 -- generate a call to the _Rep_To_Pos function created when the 2423 -- type was frozen. The call has the form 2424 2425 -- _rep_to_pos (expr, flag) 2426 2427 -- The parameter flag is True if range checks are enabled, causing 2428 -- Program_Error to be raised if the expression has an invalid 2429 -- representation, and False if range checks are suppressed. 2430 2431 -- For integer types, Pos is equivalent to a simple integer 2432 -- conversion and we rewrite it as such 2433 2434 when Attribute_Pos => Pos : 2435 declare 2436 Etyp : Entity_Id := Base_Type (Entity (Pref)); 2437 2438 begin 2439 -- Deal with zero/non-zero boolean values 2440 2441 if Is_Boolean_Type (Etyp) then 2442 Adjust_Condition (First (Exprs)); 2443 Etyp := Standard_Boolean; 2444 Set_Prefix (N, New_Occurrence_Of (Standard_Boolean, Loc)); 2445 end if; 2446 2447 -- Case of enumeration type 2448 2449 if Is_Enumeration_Type (Etyp) then 2450 2451 -- Non-standard enumeration type (generate call) 2452 2453 if Present (Enum_Pos_To_Rep (Etyp)) then 2454 Append_To (Exprs, Rep_To_Pos_Flag (Etyp, Loc)); 2455 Rewrite (N, 2456 Convert_To (Typ, 2457 Make_Function_Call (Loc, 2458 Name => 2459 New_Reference_To (TSS (Etyp, TSS_Rep_To_Pos), Loc), 2460 Parameter_Associations => Exprs))); 2461 2462 Analyze_And_Resolve (N, Typ); 2463 2464 -- Standard enumeration type (do universal integer check) 2465 2466 else 2467 Apply_Universal_Integer_Attribute_Checks (N); 2468 end if; 2469 2470 -- Deal with integer types (replace by conversion) 2471 2472 elsif Is_Integer_Type (Etyp) then 2473 Rewrite (N, Convert_To (Typ, First (Exprs))); 2474 Analyze_And_Resolve (N, Typ); 2475 end if; 2476 2477 end Pos; 2478 2479 -------------- 2480 -- Position -- 2481 -------------- 2482 2483 -- We compute this if a component clause was present, otherwise 2484 -- we leave the computation up to Gigi, since we don't know what 2485 -- layout will be chosen. 2486 2487 when Attribute_Position => Position : 2488 declare 2489 CE : constant Entity_Id := Entity (Selector_Name (Pref)); 2490 2491 begin 2492 if Present (Component_Clause (CE)) then 2493 Rewrite (N, 2494 Make_Integer_Literal (Loc, 2495 Intval => Component_Bit_Offset (CE) / System_Storage_Unit)); 2496 Analyze_And_Resolve (N, Typ); 2497 2498 else 2499 Apply_Universal_Integer_Attribute_Checks (N); 2500 end if; 2501 end Position; 2502 2503 ---------- 2504 -- Pred -- 2505 ---------- 2506 2507 -- 1. Deal with enumeration types with holes 2508 -- 2. For floating-point, generate call to attribute function 2509 -- 3. For other cases, deal with constraint checking 2510 2511 when Attribute_Pred => Pred : 2512 declare 2513 Ptyp : constant Entity_Id := Base_Type (Etype (Pref)); 2514 2515 begin 2516 -- For enumeration types with non-standard representations, we 2517 -- expand typ'Pred (x) into 2518 2519 -- Pos_To_Rep (Rep_To_Pos (x) - 1) 2520 2521 -- If the representation is contiguous, we compute instead 2522 -- Lit1 + Rep_to_Pos (x -1), to catch invalid representations. 2523 2524 if Is_Enumeration_Type (Ptyp) 2525 and then Present (Enum_Pos_To_Rep (Ptyp)) 2526 then 2527 if Has_Contiguous_Rep (Ptyp) then 2528 Rewrite (N, 2529 Unchecked_Convert_To (Ptyp, 2530 Make_Op_Add (Loc, 2531 Left_Opnd => 2532 Make_Integer_Literal (Loc, 2533 Enumeration_Rep (First_Literal (Ptyp))), 2534 Right_Opnd => 2535 Make_Function_Call (Loc, 2536 Name => 2537 New_Reference_To 2538 (TSS (Ptyp, TSS_Rep_To_Pos), Loc), 2539 2540 Parameter_Associations => 2541 New_List ( 2542 Unchecked_Convert_To (Ptyp, 2543 Make_Op_Subtract (Loc, 2544 Left_Opnd => 2545 Unchecked_Convert_To (Standard_Integer, 2546 Relocate_Node (First (Exprs))), 2547 Right_Opnd => 2548 Make_Integer_Literal (Loc, 1))), 2549 Rep_To_Pos_Flag (Ptyp, Loc)))))); 2550 2551 else 2552 -- Add Boolean parameter True, to request program errror if 2553 -- we have a bad representation on our hands. If checks are 2554 -- suppressed, then add False instead 2555 2556 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc)); 2557 Rewrite (N, 2558 Make_Indexed_Component (Loc, 2559 Prefix => New_Reference_To (Enum_Pos_To_Rep (Ptyp), Loc), 2560 Expressions => New_List ( 2561 Make_Op_Subtract (Loc, 2562 Left_Opnd => 2563 Make_Function_Call (Loc, 2564 Name => 2565 New_Reference_To (TSS (Ptyp, TSS_Rep_To_Pos), Loc), 2566 Parameter_Associations => Exprs), 2567 Right_Opnd => Make_Integer_Literal (Loc, 1))))); 2568 end if; 2569 2570 Analyze_And_Resolve (N, Typ); 2571 2572 -- For floating-point, we transform 'Pred into a call to the Pred 2573 -- floating-point attribute function in Fat_xxx (xxx is root type) 2574 2575 elsif Is_Floating_Point_Type (Ptyp) then 2576 Expand_Fpt_Attribute_R (N); 2577 Analyze_And_Resolve (N, Typ); 2578 2579 -- For modular types, nothing to do (no overflow, since wraps) 2580 2581 elsif Is_Modular_Integer_Type (Ptyp) then 2582 null; 2583 2584 -- For other types, if range checking is enabled, we must generate 2585 -- a check if overflow checking is enabled. 2586 2587 elsif not Overflow_Checks_Suppressed (Ptyp) then 2588 Expand_Pred_Succ (N); 2589 end if; 2590 2591 end Pred; 2592 2593 ------------------ 2594 -- Range_Length -- 2595 ------------------ 2596 2597 when Attribute_Range_Length => Range_Length : declare 2598 P_Type : constant Entity_Id := Etype (Pref); 2599 2600 begin 2601 -- The only special processing required is for the case where 2602 -- Range_Length is applied to an enumeration type with holes. 2603 -- In this case we transform 2604 2605 -- X'Range_Length 2606 2607 -- to 2608 2609 -- X'Pos (X'Last) - X'Pos (X'First) + 1 2610 2611 -- So that the result reflects the proper Pos values instead 2612 -- of the underlying representations. 2613 2614 if Is_Enumeration_Type (P_Type) 2615 and then Has_Non_Standard_Rep (P_Type) 2616 then 2617 Rewrite (N, 2618 Make_Op_Add (Loc, 2619 Left_Opnd => 2620 Make_Op_Subtract (Loc, 2621 Left_Opnd => 2622 Make_Attribute_Reference (Loc, 2623 Attribute_Name => Name_Pos, 2624 Prefix => New_Occurrence_Of (P_Type, Loc), 2625 Expressions => New_List ( 2626 Make_Attribute_Reference (Loc, 2627 Attribute_Name => Name_Last, 2628 Prefix => New_Occurrence_Of (P_Type, Loc)))), 2629 2630 Right_Opnd => 2631 Make_Attribute_Reference (Loc, 2632 Attribute_Name => Name_Pos, 2633 Prefix => New_Occurrence_Of (P_Type, Loc), 2634 Expressions => New_List ( 2635 Make_Attribute_Reference (Loc, 2636 Attribute_Name => Name_First, 2637 Prefix => New_Occurrence_Of (P_Type, Loc))))), 2638 2639 Right_Opnd => 2640 Make_Integer_Literal (Loc, 1))); 2641 2642 Analyze_And_Resolve (N, Typ); 2643 2644 -- For all other cases, attribute is handled by Gigi, but we need 2645 -- to deal with the case of the range check on a universal integer. 2646 2647 else 2648 Apply_Universal_Integer_Attribute_Checks (N); 2649 end if; 2650 2651 end Range_Length; 2652 2653 ---------- 2654 -- Read -- 2655 ---------- 2656 2657 when Attribute_Read => Read : declare 2658 P_Type : constant Entity_Id := Entity (Pref); 2659 B_Type : constant Entity_Id := Base_Type (P_Type); 2660 U_Type : constant Entity_Id := Underlying_Type (P_Type); 2661 Pname : Entity_Id; 2662 Decl : Node_Id; 2663 Prag : Node_Id; 2664 Arg2 : Node_Id; 2665 Rfunc : Node_Id; 2666 Lhs : Node_Id; 2667 Rhs : Node_Id; 2668 2669 begin 2670 -- If no underlying type, we have an error that will be diagnosed 2671 -- elsewhere, so here we just completely ignore the expansion. 2672 2673 if No (U_Type) then 2674 return; 2675 end if; 2676 2677 -- The simple case, if there is a TSS for Read, just call it 2678 2679 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Read); 2680 2681 if Present (Pname) then 2682 null; 2683 2684 else 2685 -- If there is a Stream_Convert pragma, use it, we rewrite 2686 2687 -- sourcetyp'Read (stream, Item) 2688 2689 -- as 2690 2691 -- Item := sourcetyp (strmread (strmtyp'Input (Stream))); 2692 2693 -- where strmread is the given Read function that converts 2694 -- an argument of type strmtyp to type sourcetyp or a type 2695 -- from which it is derived. The conversion to sourcetyp 2696 -- is required in the latter case. 2697 2698 -- A special case arises if Item is a type conversion in which 2699 -- case, we have to expand to: 2700 2701 -- Itemx := typex (strmread (strmtyp'Input (Stream))); 2702 2703 -- where Itemx is the expression of the type conversion (i.e. 2704 -- the actual object), and typex is the type of Itemx. 2705 2706 Prag := 2707 Get_Rep_Pragma 2708 (Implementation_Base_Type (P_Type), Name_Stream_Convert); 2709 2710 if Present (Prag) then 2711 Arg2 := Next (First (Pragma_Argument_Associations (Prag))); 2712 Rfunc := Entity (Expression (Arg2)); 2713 Lhs := Relocate_Node (Next (First (Exprs))); 2714 Rhs := 2715 Convert_To (B_Type, 2716 Make_Function_Call (Loc, 2717 Name => New_Occurrence_Of (Rfunc, Loc), 2718 Parameter_Associations => New_List ( 2719 Make_Attribute_Reference (Loc, 2720 Prefix => 2721 New_Occurrence_Of 2722 (Etype (First_Formal (Rfunc)), Loc), 2723 Attribute_Name => Name_Input, 2724 Expressions => New_List ( 2725 Relocate_Node (First (Exprs))))))); 2726 2727 if Nkind (Lhs) = N_Type_Conversion then 2728 Lhs := Expression (Lhs); 2729 Rhs := Convert_To (Etype (Lhs), Rhs); 2730 end if; 2731 2732 Rewrite (N, 2733 Make_Assignment_Statement (Loc, 2734 Name => Lhs, 2735 Expression => Rhs)); 2736 Set_Assignment_OK (Lhs); 2737 Analyze (N); 2738 return; 2739 2740 -- For elementary types, we call the I_xxx routine using the first 2741 -- parameter and then assign the result into the second parameter. 2742 -- We set Assignment_OK to deal with the conversion case. 2743 2744 elsif Is_Elementary_Type (U_Type) then 2745 declare 2746 Lhs : Node_Id; 2747 Rhs : Node_Id; 2748 2749 begin 2750 Lhs := Relocate_Node (Next (First (Exprs))); 2751 Rhs := Build_Elementary_Input_Call (N); 2752 2753 if Nkind (Lhs) = N_Type_Conversion then 2754 Lhs := Expression (Lhs); 2755 Rhs := Convert_To (Etype (Lhs), Rhs); 2756 end if; 2757 2758 Set_Assignment_OK (Lhs); 2759 2760 Rewrite (N, 2761 Make_Assignment_Statement (Loc, 2762 Name => Lhs, 2763 Expression => Rhs)); 2764 2765 Analyze (N); 2766 return; 2767 end; 2768 2769 -- Array type case 2770 2771 elsif Is_Array_Type (U_Type) then 2772 Build_Array_Read_Procedure (N, U_Type, Decl, Pname); 2773 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False); 2774 2775 -- Tagged type case, use the primitive Read function. Note that 2776 -- this will dispatch in the class-wide case which is what we want 2777 2778 elsif Is_Tagged_Type (U_Type) then 2779 Pname := Find_Prim_Op (U_Type, TSS_Stream_Read); 2780 2781 -- All other record type cases, including protected records. 2782 -- The latter only arise for expander generated code for 2783 -- handling shared passive partition access. 2784 2785 else 2786 pragma Assert 2787 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type)); 2788 2789 if Has_Discriminants (U_Type) 2790 and then Present 2791 (Discriminant_Default_Value (First_Discriminant (U_Type))) 2792 then 2793 Build_Mutable_Record_Read_Procedure 2794 (Loc, Base_Type (U_Type), Decl, Pname); 2795 2796 else 2797 Build_Record_Read_Procedure 2798 (Loc, Base_Type (U_Type), Decl, Pname); 2799 end if; 2800 2801 -- Suppress checks, uninitialized or otherwise invalid 2802 -- data does not cause constraint errors to be raised for 2803 -- a complete record read. 2804 2805 Insert_Action (N, Decl, All_Checks); 2806 end if; 2807 end if; 2808 2809 Rewrite_Stream_Proc_Call (Pname); 2810 end Read; 2811 2812 --------------- 2813 -- Remainder -- 2814 --------------- 2815 2816 -- Transforms 'Remainder into a call to the floating-point attribute 2817 -- function Remainder in Fat_xxx (where xxx is the root type) 2818 2819 when Attribute_Remainder => 2820 Expand_Fpt_Attribute_RR (N); 2821 2822 ----------- 2823 -- Round -- 2824 ----------- 2825 2826 -- The handling of the Round attribute is quite delicate. The 2827 -- processing in Sem_Attr introduced a conversion to universal 2828 -- real, reflecting the semantics of Round, but we do not want 2829 -- anything to do with universal real at runtime, since this 2830 -- corresponds to using floating-point arithmetic. 2831 2832 -- What we have now is that the Etype of the Round attribute 2833 -- correctly indicates the final result type. The operand of 2834 -- the Round is the conversion to universal real, described 2835 -- above, and the operand of this conversion is the actual 2836 -- operand of Round, which may be the special case of a fixed 2837 -- point multiplication or division (Etype = universal fixed) 2838 2839 -- The exapander will expand first the operand of the conversion, 2840 -- then the conversion, and finally the round attribute itself, 2841 -- since we always work inside out. But we cannot simply process 2842 -- naively in this order. In the semantic world where universal 2843 -- fixed and real really exist and have infinite precision, there 2844 -- is no problem, but in the implementation world, where universal 2845 -- real is a floating-point type, we would get the wrong result. 2846 2847 -- So the approach is as follows. First, when expanding a multiply 2848 -- or divide whose type is universal fixed, we do nothing at all, 2849 -- instead deferring the operation till later. 2850 2851 -- The actual processing is done in Expand_N_Type_Conversion which 2852 -- handles the special case of Round by looking at its parent to 2853 -- see if it is a Round attribute, and if it is, handling the 2854 -- conversion (or its fixed multiply/divide child) in an appropriate 2855 -- manner. 2856 2857 -- This means that by the time we get to expanding the Round attribute 2858 -- itself, the Round is nothing more than a type conversion (and will 2859 -- often be a null type conversion), so we just replace it with the 2860 -- appropriate conversion operation. 2861 2862 when Attribute_Round => 2863 Rewrite (N, 2864 Convert_To (Etype (N), Relocate_Node (First (Exprs)))); 2865 Analyze_And_Resolve (N); 2866 2867 -------------- 2868 -- Rounding -- 2869 -------------- 2870 2871 -- Transforms 'Rounding into a call to the floating-point attribute 2872 -- function Rounding in Fat_xxx (where xxx is the root type) 2873 2874 when Attribute_Rounding => 2875 Expand_Fpt_Attribute_R (N); 2876 2877 ------------- 2878 -- Scaling -- 2879 ------------- 2880 2881 -- Transforms 'Scaling into a call to the floating-point attribute 2882 -- function Scaling in Fat_xxx (where xxx is the root type) 2883 2884 when Attribute_Scaling => 2885 Expand_Fpt_Attribute_RI (N); 2886 2887 ---------- 2888 -- Size -- 2889 ---------- 2890 2891 when Attribute_Size | 2892 Attribute_Object_Size | 2893 Attribute_Value_Size | 2894 Attribute_VADS_Size => Size : 2895 2896 declare 2897 Ptyp : constant Entity_Id := Etype (Pref); 2898 Siz : Uint; 2899 New_Node : Node_Id; 2900 2901 begin 2902 -- Processing for VADS_Size case. Note that this processing removes 2903 -- all traces of VADS_Size from the tree, and completes all required 2904 -- processing for VADS_Size by translating the attribute reference 2905 -- to an appropriate Size or Object_Size reference. 2906 2907 if Id = Attribute_VADS_Size 2908 or else (Use_VADS_Size and then Id = Attribute_Size) 2909 then 2910 -- If the size is specified, then we simply use the specified 2911 -- size. This applies to both types and objects. The size of an 2912 -- object can be specified in the following ways: 2913 2914 -- An explicit size object is given for an object 2915 -- A component size is specified for an indexed component 2916 -- A component clause is specified for a selected component 2917 -- The object is a component of a packed composite object 2918 2919 -- If the size is specified, then VADS_Size of an object 2920 2921 if (Is_Entity_Name (Pref) 2922 and then Present (Size_Clause (Entity (Pref)))) 2923 or else 2924 (Nkind (Pref) = N_Component_Clause 2925 and then (Present (Component_Clause 2926 (Entity (Selector_Name (Pref)))) 2927 or else Is_Packed (Etype (Prefix (Pref))))) 2928 or else 2929 (Nkind (Pref) = N_Indexed_Component 2930 and then (Component_Size (Etype (Prefix (Pref))) /= 0 2931 or else Is_Packed (Etype (Prefix (Pref))))) 2932 then 2933 Set_Attribute_Name (N, Name_Size); 2934 2935 -- Otherwise if we have an object rather than a type, then the 2936 -- VADS_Size attribute applies to the type of the object, rather 2937 -- than the object itself. This is one of the respects in which 2938 -- VADS_Size differs from Size. 2939 2940 else 2941 if (not Is_Entity_Name (Pref) 2942 or else not Is_Type (Entity (Pref))) 2943 and then (Is_Scalar_Type (Etype (Pref)) 2944 or else Is_Constrained (Etype (Pref))) 2945 then 2946 Rewrite (Pref, New_Occurrence_Of (Etype (Pref), Loc)); 2947 end if; 2948 2949 -- For a scalar type for which no size was 2950 -- explicitly given, VADS_Size means Object_Size. This is the 2951 -- other respect in which VADS_Size differs from Size. 2952 2953 if Is_Scalar_Type (Etype (Pref)) 2954 and then No (Size_Clause (Etype (Pref))) 2955 then 2956 Set_Attribute_Name (N, Name_Object_Size); 2957 2958 -- In all other cases, Size and VADS_Size are the sane 2959 2960 else 2961 Set_Attribute_Name (N, Name_Size); 2962 end if; 2963 end if; 2964 end if; 2965 2966 -- For class-wide types, X'Class'Size is transformed into a 2967 -- direct reference to the Size of the class type, so that gigi 2968 -- does not have to deal with the X'Class'Size reference. 2969 2970 if Is_Entity_Name (Pref) 2971 and then Is_Class_Wide_Type (Entity (Pref)) 2972 then 2973 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc)); 2974 return; 2975 2976 -- For x'Size applied to an object of a class wide type, transform 2977 -- X'Size into a call to the primitive operation _Size applied to X. 2978 2979 elsif Is_Class_Wide_Type (Ptyp) then 2980 New_Node := 2981 Make_Function_Call (Loc, 2982 Name => New_Reference_To 2983 (Find_Prim_Op (Ptyp, Name_uSize), Loc), 2984 Parameter_Associations => New_List (Pref)); 2985 2986 if Typ /= Standard_Long_Long_Integer then 2987 2988 -- The context is a specific integer type with which the 2989 -- original attribute was compatible. The function has a 2990 -- specific type as well, so to preserve the compatibility 2991 -- we must convert explicitly. 2992 2993 New_Node := Convert_To (Typ, New_Node); 2994 end if; 2995 2996 Rewrite (N, New_Node); 2997 Analyze_And_Resolve (N, Typ); 2998 return; 2999 3000 -- For an array component, we can do Size in the front end 3001 -- if the component_size of the array is set. 3002 3003 elsif Nkind (Pref) = N_Indexed_Component then 3004 Siz := Component_Size (Etype (Prefix (Pref))); 3005 3006 -- For a record component, we can do Size in the front end 3007 -- if there is a component clause, or if the record is packed 3008 -- and the component's size is known at compile time. 3009 3010 elsif Nkind (Pref) = N_Selected_Component then 3011 declare 3012 Rec : constant Entity_Id := Etype (Prefix (Pref)); 3013 Comp : constant Entity_Id := Entity (Selector_Name (Pref)); 3014 3015 begin 3016 if Present (Component_Clause (Comp)) then 3017 Siz := Esize (Comp); 3018 3019 elsif Is_Packed (Rec) then 3020 Siz := RM_Size (Ptyp); 3021 3022 else 3023 Apply_Universal_Integer_Attribute_Checks (N); 3024 return; 3025 end if; 3026 end; 3027 3028 -- All other cases are handled by Gigi 3029 3030 else 3031 Apply_Universal_Integer_Attribute_Checks (N); 3032 3033 -- If we have Size applied to a formal parameter, that is a 3034 -- packed array subtype, then apply size to the actual subtype. 3035 3036 if Is_Entity_Name (Pref) 3037 and then Is_Formal (Entity (Pref)) 3038 and then Is_Array_Type (Etype (Pref)) 3039 and then Is_Packed (Etype (Pref)) 3040 then 3041 Rewrite (N, 3042 Make_Attribute_Reference (Loc, 3043 Prefix => 3044 New_Occurrence_Of (Get_Actual_Subtype (Pref), Loc), 3045 Attribute_Name => Name_Size)); 3046 Analyze_And_Resolve (N, Typ); 3047 end if; 3048 3049 return; 3050 end if; 3051 3052 -- Common processing for record and array component case 3053 3054 if Siz /= 0 then 3055 Rewrite (N, 3056 Make_Integer_Literal (Loc, Siz)); 3057 3058 Analyze_And_Resolve (N, Typ); 3059 3060 -- The result is not a static expression 3061 3062 Set_Is_Static_Expression (N, False); 3063 end if; 3064 end Size; 3065 3066 ------------------ 3067 -- Storage_Pool -- 3068 ------------------ 3069 3070 when Attribute_Storage_Pool => 3071 Rewrite (N, 3072 Make_Type_Conversion (Loc, 3073 Subtype_Mark => New_Reference_To (Etype (N), Loc), 3074 Expression => New_Reference_To (Entity (N), Loc))); 3075 Analyze_And_Resolve (N, Typ); 3076 3077 ------------------ 3078 -- Storage_Size -- 3079 ------------------ 3080 3081 when Attribute_Storage_Size => Storage_Size : 3082 declare 3083 Ptyp : constant Entity_Id := Etype (Pref); 3084 3085 begin 3086 -- Access type case, always go to the root type 3087 3088 -- The case of access types results in a value of zero for the case 3089 -- where no storage size attribute clause has been given. If a 3090 -- storage size has been given, then the attribute is converted 3091 -- to a reference to the variable used to hold this value. 3092 3093 if Is_Access_Type (Ptyp) then 3094 if Present (Storage_Size_Variable (Root_Type (Ptyp))) then 3095 Rewrite (N, 3096 Make_Attribute_Reference (Loc, 3097 Prefix => New_Reference_To (Typ, Loc), 3098 Attribute_Name => Name_Max, 3099 Expressions => New_List ( 3100 Make_Integer_Literal (Loc, 0), 3101 Convert_To (Typ, 3102 New_Reference_To 3103 (Storage_Size_Variable (Root_Type (Ptyp)), Loc))))); 3104 3105 elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then 3106 Rewrite (N, 3107 OK_Convert_To (Typ, 3108 Make_Function_Call (Loc, 3109 Name => 3110 New_Reference_To 3111 (Find_Prim_Op 3112 (Etype (Associated_Storage_Pool (Root_Type (Ptyp))), 3113 Attribute_Name (N)), 3114 Loc), 3115 3116 Parameter_Associations => New_List (New_Reference_To ( 3117 Associated_Storage_Pool (Root_Type (Ptyp)), Loc))))); 3118 else 3119 Rewrite (N, Make_Integer_Literal (Loc, 0)); 3120 end if; 3121 3122 Analyze_And_Resolve (N, Typ); 3123 3124 -- The case of a task type (an obsolescent feature) is handled the 3125 -- same way, seems as reasonable as anything, and it is what the 3126 -- ACVC tests (e.g. CD1009K) seem to expect. 3127 3128 -- If there is no Storage_Size variable, then we return the default 3129 -- task stack size, otherwise, expand a Storage_Size attribute as 3130 -- follows: 3131 3132 -- Typ (Adjust_Storage_Size (taskZ)) 3133 3134 -- except for the case of a task object which has a Storage_Size 3135 -- pragma: 3136 3137 -- Typ (Adjust_Storage_Size (taskV!(name)._Size)) 3138 3139 else 3140 if not Present (Storage_Size_Variable (Ptyp)) then 3141 Rewrite (N, 3142 Convert_To (Typ, 3143 Make_Function_Call (Loc, 3144 Name => 3145 New_Occurrence_Of (RTE (RE_Default_Stack_Size), Loc)))); 3146 3147 else 3148 if not (Is_Entity_Name (Pref) and then 3149 Is_Task_Type (Entity (Pref))) and then 3150 Chars (Last_Entity (Corresponding_Record_Type (Ptyp))) = 3151 Name_uSize 3152 then 3153 Rewrite (N, 3154 Convert_To (Typ, 3155 Make_Function_Call (Loc, 3156 Name => New_Occurrence_Of ( 3157 RTE (RE_Adjust_Storage_Size), Loc), 3158 Parameter_Associations => 3159 New_List ( 3160 Make_Selected_Component (Loc, 3161 Prefix => 3162 Unchecked_Convert_To ( 3163 Corresponding_Record_Type (Ptyp), 3164 New_Copy_Tree (Pref)), 3165 Selector_Name => 3166 Make_Identifier (Loc, Name_uSize)))))); 3167 3168 -- Task not having Storage_Size pragma 3169 3170 else 3171 Rewrite (N, 3172 Convert_To (Typ, 3173 Make_Function_Call (Loc, 3174 Name => New_Occurrence_Of ( 3175 RTE (RE_Adjust_Storage_Size), Loc), 3176 Parameter_Associations => 3177 New_List ( 3178 New_Reference_To ( 3179 Storage_Size_Variable (Ptyp), Loc))))); 3180 end if; 3181 3182 Analyze_And_Resolve (N, Typ); 3183 end if; 3184 end if; 3185 end Storage_Size; 3186 3187 ---------- 3188 -- Succ -- 3189 ---------- 3190 3191 -- 1. Deal with enumeration types with holes 3192 -- 2. For floating-point, generate call to attribute function 3193 -- 3. For other cases, deal with constraint checking 3194 3195 when Attribute_Succ => Succ : 3196 declare 3197 Ptyp : constant Entity_Id := Base_Type (Etype (Pref)); 3198 3199 begin 3200 -- For enumeration types with non-standard representations, we 3201 -- expand typ'Succ (x) into 3202 3203 -- Pos_To_Rep (Rep_To_Pos (x) + 1) 3204 3205 -- If the representation is contiguous, we compute instead 3206 -- Lit1 + Rep_to_Pos (x+1), to catch invalid representations. 3207 3208 if Is_Enumeration_Type (Ptyp) 3209 and then Present (Enum_Pos_To_Rep (Ptyp)) 3210 then 3211 if Has_Contiguous_Rep (Ptyp) then 3212 Rewrite (N, 3213 Unchecked_Convert_To (Ptyp, 3214 Make_Op_Add (Loc, 3215 Left_Opnd => 3216 Make_Integer_Literal (Loc, 3217 Enumeration_Rep (First_Literal (Ptyp))), 3218 Right_Opnd => 3219 Make_Function_Call (Loc, 3220 Name => 3221 New_Reference_To 3222 (TSS (Ptyp, TSS_Rep_To_Pos), Loc), 3223 3224 Parameter_Associations => 3225 New_List ( 3226 Unchecked_Convert_To (Ptyp, 3227 Make_Op_Add (Loc, 3228 Left_Opnd => 3229 Unchecked_Convert_To (Standard_Integer, 3230 Relocate_Node (First (Exprs))), 3231 Right_Opnd => 3232 Make_Integer_Literal (Loc, 1))), 3233 Rep_To_Pos_Flag (Ptyp, Loc)))))); 3234 else 3235 -- Add Boolean parameter True, to request program errror if 3236 -- we have a bad representation on our hands. Add False if 3237 -- checks are suppressed. 3238 3239 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc)); 3240 Rewrite (N, 3241 Make_Indexed_Component (Loc, 3242 Prefix => New_Reference_To (Enum_Pos_To_Rep (Ptyp), Loc), 3243 Expressions => New_List ( 3244 Make_Op_Add (Loc, 3245 Left_Opnd => 3246 Make_Function_Call (Loc, 3247 Name => 3248 New_Reference_To 3249 (TSS (Ptyp, TSS_Rep_To_Pos), Loc), 3250 Parameter_Associations => Exprs), 3251 Right_Opnd => Make_Integer_Literal (Loc, 1))))); 3252 end if; 3253 3254 Analyze_And_Resolve (N, Typ); 3255 3256 -- For floating-point, we transform 'Succ into a call to the Succ 3257 -- floating-point attribute function in Fat_xxx (xxx is root type) 3258 3259 elsif Is_Floating_Point_Type (Ptyp) then 3260 Expand_Fpt_Attribute_R (N); 3261 Analyze_And_Resolve (N, Typ); 3262 3263 -- For modular types, nothing to do (no overflow, since wraps) 3264 3265 elsif Is_Modular_Integer_Type (Ptyp) then 3266 null; 3267 3268 -- For other types, if range checking is enabled, we must generate 3269 -- a check if overflow checking is enabled. 3270 3271 elsif not Overflow_Checks_Suppressed (Ptyp) then 3272 Expand_Pred_Succ (N); 3273 end if; 3274 end Succ; 3275 3276 --------- 3277 -- Tag -- 3278 --------- 3279 3280 -- Transforms X'Tag into a direct reference to the tag of X 3281 3282 when Attribute_Tag => Tag : 3283 declare 3284 Ttyp : Entity_Id; 3285 Prefix_Is_Type : Boolean; 3286 3287 begin 3288 if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then 3289 Ttyp := Entity (Pref); 3290 Prefix_Is_Type := True; 3291 else 3292 Ttyp := Etype (Pref); 3293 Prefix_Is_Type := False; 3294 end if; 3295 3296 if Is_Class_Wide_Type (Ttyp) then 3297 Ttyp := Root_Type (Ttyp); 3298 end if; 3299 3300 Ttyp := Underlying_Type (Ttyp); 3301 3302 if Prefix_Is_Type then 3303 3304 -- For JGNAT we leave the type attribute unexpanded because 3305 -- there's not a dispatching table to reference. 3306 3307 if not Java_VM then 3308 Rewrite (N, 3309 Unchecked_Convert_To (RTE (RE_Tag), 3310 New_Reference_To (Access_Disp_Table (Ttyp), Loc))); 3311 Analyze_And_Resolve (N, RTE (RE_Tag)); 3312 end if; 3313 3314 else 3315 Rewrite (N, 3316 Make_Selected_Component (Loc, 3317 Prefix => Relocate_Node (Pref), 3318 Selector_Name => 3319 New_Reference_To (Tag_Component (Ttyp), Loc))); 3320 Analyze_And_Resolve (N, RTE (RE_Tag)); 3321 end if; 3322 end Tag; 3323 3324 ---------------- 3325 -- Terminated -- 3326 ---------------- 3327 3328 -- Transforms 'Terminated attribute into a call to Terminated function. 3329 3330 when Attribute_Terminated => Terminated : 3331 begin 3332 if Restricted_Profile then 3333 Rewrite (N, 3334 Build_Call_With_Task (Pref, RTE (RE_Restricted_Terminated))); 3335 3336 else 3337 Rewrite (N, 3338 Build_Call_With_Task (Pref, RTE (RE_Terminated))); 3339 end if; 3340 3341 Analyze_And_Resolve (N, Standard_Boolean); 3342 end Terminated; 3343 3344 ---------------- 3345 -- To_Address -- 3346 ---------------- 3347 3348 -- Transforms System'To_Address (X) into unchecked conversion 3349 -- from (integral) type of X to type address. 3350 3351 when Attribute_To_Address => 3352 Rewrite (N, 3353 Unchecked_Convert_To (RTE (RE_Address), 3354 Relocate_Node (First (Exprs)))); 3355 Analyze_And_Resolve (N, RTE (RE_Address)); 3356 3357 ---------------- 3358 -- Truncation -- 3359 ---------------- 3360 3361 -- Transforms 'Truncation into a call to the floating-point attribute 3362 -- function Truncation in Fat_xxx (where xxx is the root type) 3363 3364 when Attribute_Truncation => 3365 Expand_Fpt_Attribute_R (N); 3366 3367 ----------------------- 3368 -- Unbiased_Rounding -- 3369 ----------------------- 3370 3371 -- Transforms 'Unbiased_Rounding into a call to the floating-point 3372 -- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the 3373 -- root type) 3374 3375 when Attribute_Unbiased_Rounding => 3376 Expand_Fpt_Attribute_R (N); 3377 3378 ---------------------- 3379 -- Unchecked_Access -- 3380 ---------------------- 3381 3382 when Attribute_Unchecked_Access => 3383 Expand_Access_To_Type (N); 3384 3385 ----------------- 3386 -- UET_Address -- 3387 ----------------- 3388 3389 when Attribute_UET_Address => UET_Address : declare 3390 Ent : constant Entity_Id := 3391 Make_Defining_Identifier (Loc, New_Internal_Name ('T')); 3392 3393 begin 3394 Insert_Action (N, 3395 Make_Object_Declaration (Loc, 3396 Defining_Identifier => Ent, 3397 Aliased_Present => True, 3398 Object_Definition => 3399 New_Occurrence_Of (RTE (RE_Address), Loc))); 3400 3401 -- Construct name __gnat_xxx__SDP, where xxx is the unit name 3402 -- in normal external form. 3403 3404 Get_External_Unit_Name_String (Get_Unit_Name (Pref)); 3405 Name_Buffer (1 + 7 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len); 3406 Name_Len := Name_Len + 7; 3407 Name_Buffer (1 .. 7) := "__gnat_"; 3408 Name_Buffer (Name_Len + 1 .. Name_Len + 5) := "__SDP"; 3409 Name_Len := Name_Len + 5; 3410 3411 Set_Is_Imported (Ent); 3412 Set_Interface_Name (Ent, 3413 Make_String_Literal (Loc, 3414 Strval => String_From_Name_Buffer)); 3415 3416 Rewrite (N, 3417 Make_Attribute_Reference (Loc, 3418 Prefix => New_Occurrence_Of (Ent, Loc), 3419 Attribute_Name => Name_Address)); 3420 3421 Analyze_And_Resolve (N, Typ); 3422 end UET_Address; 3423 3424 ------------------------- 3425 -- Unrestricted_Access -- 3426 ------------------------- 3427 3428 when Attribute_Unrestricted_Access => 3429 Expand_Access_To_Type (N); 3430 3431 --------------- 3432 -- VADS_Size -- 3433 --------------- 3434 3435 -- The processing for VADS_Size is shared with Size 3436 3437 --------- 3438 -- Val -- 3439 --------- 3440 3441 -- For enumeration types with a standard representation, and for all 3442 -- other types, Val is handled by Gigi. For enumeration types with 3443 -- a non-standard representation we use the _Pos_To_Rep array that 3444 -- was created when the type was frozen. 3445 3446 when Attribute_Val => Val : 3447 declare 3448 Etyp : constant Entity_Id := Base_Type (Entity (Pref)); 3449 3450 begin 3451 if Is_Enumeration_Type (Etyp) 3452 and then Present (Enum_Pos_To_Rep (Etyp)) 3453 then 3454 if Has_Contiguous_Rep (Etyp) then 3455 declare 3456 Rep_Node : constant Node_Id := 3457 Unchecked_Convert_To (Etyp, 3458 Make_Op_Add (Loc, 3459 Left_Opnd => 3460 Make_Integer_Literal (Loc, 3461 Enumeration_Rep (First_Literal (Etyp))), 3462 Right_Opnd => 3463 (Convert_To (Standard_Integer, 3464 Relocate_Node (First (Exprs)))))); 3465 3466 begin 3467 Rewrite (N, 3468 Unchecked_Convert_To (Etyp, 3469 Make_Op_Add (Loc, 3470 Left_Opnd => 3471 Make_Integer_Literal (Loc, 3472 Enumeration_Rep (First_Literal (Etyp))), 3473 Right_Opnd => 3474 Make_Function_Call (Loc, 3475 Name => 3476 New_Reference_To 3477 (TSS (Etyp, TSS_Rep_To_Pos), Loc), 3478 Parameter_Associations => New_List ( 3479 Rep_Node, 3480 Rep_To_Pos_Flag (Etyp, Loc)))))); 3481 end; 3482 3483 else 3484 Rewrite (N, 3485 Make_Indexed_Component (Loc, 3486 Prefix => New_Reference_To (Enum_Pos_To_Rep (Etyp), Loc), 3487 Expressions => New_List ( 3488 Convert_To (Standard_Integer, 3489 Relocate_Node (First (Exprs)))))); 3490 end if; 3491 3492 Analyze_And_Resolve (N, Typ); 3493 end if; 3494 end Val; 3495 3496 ----------- 3497 -- Valid -- 3498 ----------- 3499 3500 -- The code for valid is dependent on the particular types involved. 3501 -- See separate sections below for the generated code in each case. 3502 3503 when Attribute_Valid => Valid : 3504 declare 3505 Ptyp : constant Entity_Id := Etype (Pref); 3506 Btyp : Entity_Id := Base_Type (Ptyp); 3507 Tst : Node_Id; 3508 3509 Save_Validity_Checks_On : constant Boolean := Validity_Checks_On; 3510 -- Save the validity checking mode. We always turn off validity 3511 -- checking during process of 'Valid since this is one place 3512 -- where we do not want the implicit validity checks to intefere 3513 -- with the explicit validity check that the programmer is doing. 3514 3515 function Make_Range_Test return Node_Id; 3516 -- Build the code for a range test of the form 3517 -- Btyp!(Pref) >= Btyp!(Ptyp'First) 3518 -- and then 3519 -- Btyp!(Pref) <= Btyp!(Ptyp'Last) 3520 3521 --------------------- 3522 -- Make_Range_Test -- 3523 --------------------- 3524 3525 function Make_Range_Test return Node_Id is 3526 begin 3527 return 3528 Make_And_Then (Loc, 3529 Left_Opnd => 3530 Make_Op_Ge (Loc, 3531 Left_Opnd => 3532 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)), 3533 3534 Right_Opnd => 3535 Unchecked_Convert_To (Btyp, 3536 Make_Attribute_Reference (Loc, 3537 Prefix => New_Occurrence_Of (Ptyp, Loc), 3538 Attribute_Name => Name_First))), 3539 3540 Right_Opnd => 3541 Make_Op_Le (Loc, 3542 Left_Opnd => 3543 Unchecked_Convert_To (Btyp, 3544 Duplicate_Subexpr_No_Checks (Pref)), 3545 3546 Right_Opnd => 3547 Unchecked_Convert_To (Btyp, 3548 Make_Attribute_Reference (Loc, 3549 Prefix => New_Occurrence_Of (Ptyp, Loc), 3550 Attribute_Name => Name_Last)))); 3551 end Make_Range_Test; 3552 3553 -- Start of processing for Attribute_Valid 3554 3555 begin 3556 -- Turn off validity checks. We do not want any implicit validity 3557 -- checks to intefere with the explicit check from the attribute 3558 3559 Validity_Checks_On := False; 3560 3561 -- Floating-point case. This case is handled by the Valid attribute 3562 -- code in the floating-point attribute run-time library. 3563 3564 if Is_Floating_Point_Type (Ptyp) then 3565 declare 3566 Rtp : constant Entity_Id := Root_Type (Etype (Pref)); 3567 3568 begin 3569 -- If the floating-point object might be unaligned, we need 3570 -- to call the special routine Unaligned_Valid, which makes 3571 -- the needed copy, being careful not to load the value into 3572 -- any floating-point register. The argument in this case is 3573 -- obj'Address (see Unchecked_Valid routine in s-fatgen.ads). 3574 3575 if Is_Possibly_Unaligned_Object (Pref) then 3576 Set_Attribute_Name (N, Name_Unaligned_Valid); 3577 Expand_Fpt_Attribute 3578 (N, Rtp, Name_Unaligned_Valid, 3579 New_List ( 3580 Make_Attribute_Reference (Loc, 3581 Prefix => Relocate_Node (Pref), 3582 Attribute_Name => Name_Address))); 3583 3584 -- In the normal case where we are sure the object is aligned, 3585 -- we generate a caqll to Valid, and the argument in this case 3586 -- is obj'Unrestricted_Access (after converting obj to the 3587 -- right floating-point type). 3588 3589 else 3590 Expand_Fpt_Attribute 3591 (N, Rtp, Name_Valid, 3592 New_List ( 3593 Make_Attribute_Reference (Loc, 3594 Prefix => Unchecked_Convert_To (Rtp, Pref), 3595 Attribute_Name => Name_Unrestricted_Access))); 3596 end if; 3597 3598 -- One more task, we still need a range check. Required 3599 -- only if we have a constraint, since the Valid routine 3600 -- catches infinities properly (infinities are never valid). 3601 3602 -- The way we do the range check is simply to create the 3603 -- expression: Valid (N) and then Base_Type(Pref) in Typ. 3604 3605 if not Subtypes_Statically_Match (Ptyp, Btyp) then 3606 Rewrite (N, 3607 Make_And_Then (Loc, 3608 Left_Opnd => Relocate_Node (N), 3609 Right_Opnd => 3610 Make_In (Loc, 3611 Left_Opnd => Convert_To (Btyp, Pref), 3612 Right_Opnd => New_Occurrence_Of (Ptyp, Loc)))); 3613 end if; 3614 end; 3615 3616 -- Enumeration type with holes 3617 3618 -- For enumeration types with holes, the Pos value constructed by 3619 -- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a 3620 -- second argument of False returns minus one for an invalid value, 3621 -- and the non-negative pos value for a valid value, so the 3622 -- expansion of X'Valid is simply: 3623 3624 -- type(X)'Pos (X) >= 0 3625 3626 -- We can't quite generate it that way because of the requirement 3627 -- for the non-standard second argument of False, so we have to 3628 -- explicitly create: 3629 3630 -- _rep_to_pos (X, False) >= 0 3631 3632 -- If we have an enumeration subtype, we also check that the 3633 -- value is in range: 3634 3635 -- _rep_to_pos (X, False) >= 0 3636 -- and then 3637 -- (X >= type(X)'First and then type(X)'Last <= X) 3638 3639 elsif Is_Enumeration_Type (Ptyp) 3640 and then Present (Enum_Pos_To_Rep (Base_Type (Ptyp))) 3641 then 3642 Tst := 3643 Make_Op_Ge (Loc, 3644 Left_Opnd => 3645 Make_Function_Call (Loc, 3646 Name => 3647 New_Reference_To 3648 (TSS (Base_Type (Ptyp), TSS_Rep_To_Pos), Loc), 3649 Parameter_Associations => New_List ( 3650 Pref, 3651 New_Occurrence_Of (Standard_False, Loc))), 3652 Right_Opnd => Make_Integer_Literal (Loc, 0)); 3653 3654 if Ptyp /= Btyp 3655 and then 3656 (Type_Low_Bound (Ptyp) /= Type_Low_Bound (Btyp) 3657 or else 3658 Type_High_Bound (Ptyp) /= Type_High_Bound (Btyp)) 3659 then 3660 -- The call to Make_Range_Test will create declarations 3661 -- that need a proper insertion point, but Pref is now 3662 -- attached to a node with no ancestor. Attach to tree 3663 -- even if it is to be rewritten below. 3664 3665 Set_Parent (Tst, Parent (N)); 3666 3667 Tst := 3668 Make_And_Then (Loc, 3669 Left_Opnd => Make_Range_Test, 3670 Right_Opnd => Tst); 3671 end if; 3672 3673 Rewrite (N, Tst); 3674 3675 -- Fortran convention booleans 3676 3677 -- For the very special case of Fortran convention booleans, the 3678 -- value is always valid, since it is an integer with the semantics 3679 -- that non-zero is true, and any value is permissible. 3680 3681 elsif Is_Boolean_Type (Ptyp) 3682 and then Convention (Ptyp) = Convention_Fortran 3683 then 3684 Rewrite (N, New_Occurrence_Of (Standard_True, Loc)); 3685 3686 -- For biased representations, we will be doing an unchecked 3687 -- conversion without unbiasing the result. That means that 3688 -- the range test has to take this into account, and the 3689 -- proper form of the test is: 3690 3691 -- Btyp!(Pref) < Btyp!(Ptyp'Range_Length) 3692 3693 elsif Has_Biased_Representation (Ptyp) then 3694 Btyp := RTE (RE_Unsigned_32); 3695 Rewrite (N, 3696 Make_Op_Lt (Loc, 3697 Left_Opnd => 3698 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)), 3699 Right_Opnd => 3700 Unchecked_Convert_To (Btyp, 3701 Make_Attribute_Reference (Loc, 3702 Prefix => New_Occurrence_Of (Ptyp, Loc), 3703 Attribute_Name => Name_Range_Length)))); 3704 3705 -- For all other scalar types, what we want logically is a 3706 -- range test: 3707 3708 -- X in type(X)'First .. type(X)'Last 3709 3710 -- But that's precisely what won't work because of possible 3711 -- unwanted optimization (and indeed the basic motivation for 3712 -- the Valid attribute -is exactly that this test does not work. 3713 -- What will work is: 3714 3715 -- Btyp!(X) >= Btyp!(type(X)'First) 3716 -- and then 3717 -- Btyp!(X) <= Btyp!(type(X)'Last) 3718 3719 -- where Btyp is an integer type large enough to cover the full 3720 -- range of possible stored values (i.e. it is chosen on the basis 3721 -- of the size of the type, not the range of the values). We write 3722 -- this as two tests, rather than a range check, so that static 3723 -- evaluation will easily remove either or both of the checks if 3724 -- they can be -statically determined to be true (this happens 3725 -- when the type of X is static and the range extends to the full 3726 -- range of stored values). 3727 3728 -- Unsigned types. Note: it is safe to consider only whether the 3729 -- subtype is unsigned, since we will in that case be doing all 3730 -- unsigned comparisons based on the subtype range. Since we use 3731 -- the actual subtype object size, this is appropriate. 3732 3733 -- For example, if we have 3734 3735 -- subtype x is integer range 1 .. 200; 3736 -- for x'Object_Size use 8; 3737 3738 -- Now the base type is signed, but objects of this type are 8 3739 -- bits unsigned, and doing an unsigned test of the range 1 to 3740 -- 200 is correct, even though a value greater than 127 looks 3741 -- signed to a signed comparison. 3742 3743 elsif Is_Unsigned_Type (Ptyp) then 3744 if Esize (Ptyp) <= 32 then 3745 Btyp := RTE (RE_Unsigned_32); 3746 else 3747 Btyp := RTE (RE_Unsigned_64); 3748 end if; 3749 3750 Rewrite (N, Make_Range_Test); 3751 3752 -- Signed types 3753 3754 else 3755 if Esize (Ptyp) <= Esize (Standard_Integer) then 3756 Btyp := Standard_Integer; 3757 else 3758 Btyp := Universal_Integer; 3759 end if; 3760 3761 Rewrite (N, Make_Range_Test); 3762 end if; 3763 3764 Analyze_And_Resolve (N, Standard_Boolean); 3765 Validity_Checks_On := Save_Validity_Checks_On; 3766 end Valid; 3767 3768 ----------- 3769 -- Value -- 3770 ----------- 3771 3772 -- Value attribute is handled in separate unti Exp_Imgv 3773 3774 when Attribute_Value => 3775 Exp_Imgv.Expand_Value_Attribute (N); 3776 3777 ----------------- 3778 -- Value_Size -- 3779 ----------------- 3780 3781 -- The processing for Value_Size shares the processing for Size 3782 3783 ------------- 3784 -- Version -- 3785 ------------- 3786 3787 -- The processing for Version shares the processing for Body_Version 3788 3789 ---------------- 3790 -- Wide_Image -- 3791 ---------------- 3792 3793 -- We expand typ'Wide_Image (X) into 3794 3795 -- String_To_Wide_String 3796 -- (typ'Image (X), Wide_Character_Encoding_Method) 3797 3798 -- This works in all cases because String_To_Wide_String converts any 3799 -- wide character escape sequences resulting from the Image call to the 3800 -- proper Wide_Character equivalent 3801 3802 -- not quite right for typ = Wide_Character ??? 3803 3804 when Attribute_Wide_Image => Wide_Image : 3805 begin 3806 Rewrite (N, 3807 Make_Function_Call (Loc, 3808 Name => New_Reference_To (RTE (RE_String_To_Wide_String), Loc), 3809 Parameter_Associations => New_List ( 3810 Make_Attribute_Reference (Loc, 3811 Prefix => Pref, 3812 Attribute_Name => Name_Image, 3813 Expressions => Exprs), 3814 3815 Make_Integer_Literal (Loc, 3816 Intval => Int (Wide_Character_Encoding_Method))))); 3817 3818 Analyze_And_Resolve (N, Standard_Wide_String); 3819 end Wide_Image; 3820 3821 ---------------- 3822 -- Wide_Value -- 3823 ---------------- 3824 3825 -- We expand typ'Wide_Value (X) into 3826 3827 -- typ'Value 3828 -- (Wide_String_To_String (X, Wide_Character_Encoding_Method)) 3829 3830 -- Wide_String_To_String is a runtime function that converts its wide 3831 -- string argument to String, converting any non-translatable characters 3832 -- into appropriate escape sequences. This preserves the required 3833 -- semantics of Wide_Value in all cases, and results in a very simple 3834 -- implementation approach. 3835 3836 -- It's not quite right where typ = Wide_Character, because the encoding 3837 -- method may not cover the whole character type ??? 3838 3839 when Attribute_Wide_Value => Wide_Value : 3840 begin 3841 Rewrite (N, 3842 Make_Attribute_Reference (Loc, 3843 Prefix => Pref, 3844 Attribute_Name => Name_Value, 3845 3846 Expressions => New_List ( 3847 Make_Function_Call (Loc, 3848 Name => 3849 New_Reference_To (RTE (RE_Wide_String_To_String), Loc), 3850 3851 Parameter_Associations => New_List ( 3852 Relocate_Node (First (Exprs)), 3853 Make_Integer_Literal (Loc, 3854 Intval => Int (Wide_Character_Encoding_Method))))))); 3855 3856 Analyze_And_Resolve (N, Typ); 3857 end Wide_Value; 3858 3859 ---------------- 3860 -- Wide_Width -- 3861 ---------------- 3862 3863 -- Wide_Width attribute is handled in separate unit Exp_Imgv 3864 3865 when Attribute_Wide_Width => 3866 Exp_Imgv.Expand_Width_Attribute (N, Wide => True); 3867 3868 ----------- 3869 -- Width -- 3870 ----------- 3871 3872 -- Width attribute is handled in separate unit Exp_Imgv 3873 3874 when Attribute_Width => 3875 Exp_Imgv.Expand_Width_Attribute (N, Wide => False); 3876 3877 ----------- 3878 -- Write -- 3879 ----------- 3880 3881 when Attribute_Write => Write : declare 3882 P_Type : constant Entity_Id := Entity (Pref); 3883 U_Type : constant Entity_Id := Underlying_Type (P_Type); 3884 Pname : Entity_Id; 3885 Decl : Node_Id; 3886 Prag : Node_Id; 3887 Arg3 : Node_Id; 3888 Wfunc : Node_Id; 3889 3890 begin 3891 -- If no underlying type, we have an error that will be diagnosed 3892 -- elsewhere, so here we just completely ignore the expansion. 3893 3894 if No (U_Type) then 3895 return; 3896 end if; 3897 3898 -- The simple case, if there is a TSS for Write, just call it 3899 3900 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Write); 3901 3902 if Present (Pname) then 3903 null; 3904 3905 else 3906 -- If there is a Stream_Convert pragma, use it, we rewrite 3907 3908 -- sourcetyp'Output (stream, Item) 3909 3910 -- as 3911 3912 -- strmtyp'Output (Stream, strmwrite (acttyp (Item))); 3913 3914 -- where strmwrite is the given Write function that converts 3915 -- an argument of type sourcetyp or a type acctyp, from which 3916 -- it is derived to type strmtyp. The conversion to acttyp is 3917 -- required for the derived case. 3918 3919 Prag := 3920 Get_Rep_Pragma 3921 (Implementation_Base_Type (P_Type), Name_Stream_Convert); 3922 3923 if Present (Prag) then 3924 Arg3 := 3925 Next (Next (First (Pragma_Argument_Associations (Prag)))); 3926 Wfunc := Entity (Expression (Arg3)); 3927 3928 Rewrite (N, 3929 Make_Attribute_Reference (Loc, 3930 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc), 3931 Attribute_Name => Name_Output, 3932 Expressions => New_List ( 3933 Relocate_Node (First (Exprs)), 3934 Make_Function_Call (Loc, 3935 Name => New_Occurrence_Of (Wfunc, Loc), 3936 Parameter_Associations => New_List ( 3937 Convert_To (Etype (First_Formal (Wfunc)), 3938 Relocate_Node (Next (First (Exprs))))))))); 3939 3940 Analyze (N); 3941 return; 3942 3943 -- For elementary types, we call the W_xxx routine directly 3944 3945 elsif Is_Elementary_Type (U_Type) then 3946 Rewrite (N, Build_Elementary_Write_Call (N)); 3947 Analyze (N); 3948 return; 3949 3950 -- Array type case 3951 3952 elsif Is_Array_Type (U_Type) then 3953 Build_Array_Write_Procedure (N, U_Type, Decl, Pname); 3954 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False); 3955 3956 -- Tagged type case, use the primitive Write function. Note that 3957 -- this will dispatch in the class-wide case which is what we want 3958 3959 elsif Is_Tagged_Type (U_Type) then 3960 Pname := Find_Prim_Op (U_Type, TSS_Stream_Write); 3961 3962 -- All other record type cases, including protected records. 3963 -- The latter only arise for expander generated code for 3964 -- handling shared passive partition access. 3965 3966 else 3967 pragma Assert 3968 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type)); 3969 3970 if Has_Discriminants (U_Type) 3971 and then Present 3972 (Discriminant_Default_Value (First_Discriminant (U_Type))) 3973 then 3974 Build_Mutable_Record_Write_Procedure 3975 (Loc, Base_Type (U_Type), Decl, Pname); 3976 3977 else 3978 Build_Record_Write_Procedure 3979 (Loc, Base_Type (U_Type), Decl, Pname); 3980 end if; 3981 3982 Insert_Action (N, Decl); 3983 end if; 3984 end if; 3985 3986 -- If we fall through, Pname is the procedure to be called 3987 3988 Rewrite_Stream_Proc_Call (Pname); 3989 end Write; 3990 3991 -- Component_Size is handled by Gigi, unless the component size is 3992 -- known at compile time, which is always true in the packed array 3993 -- case. It is important that the packed array case is handled in 3994 -- the front end (see Eval_Attribute) since Gigi would otherwise 3995 -- get confused by the equivalent packed array type. 3996 3997 when Attribute_Component_Size => 3998 null; 3999 4000 -- The following attributes are handled by Gigi (except that static 4001 -- cases have already been evaluated by the semantics, but in any 4002 -- case Gigi should not count on that). 4003 4004 -- In addition Gigi handles the non-floating-point cases of Pred 4005 -- and Succ (including the fixed-point cases, which can just be 4006 -- treated as integer increment/decrement operations) 4007 4008 -- Gigi also handles the non-class-wide cases of Size 4009 4010 when Attribute_Bit_Order | 4011 Attribute_Code_Address | 4012 Attribute_Definite | 4013 Attribute_Max | 4014 Attribute_Mechanism_Code | 4015 Attribute_Min | 4016 Attribute_Null_Parameter | 4017 Attribute_Passed_By_Reference | 4018 Attribute_Pool_Address => 4019 null; 4020 4021 -- The following attributes are also handled by Gigi, but return a 4022 -- universal integer result, so may need a conversion for checking 4023 -- that the result is in range. 4024 4025 when Attribute_Aft | 4026 Attribute_Bit | 4027 Attribute_Max_Size_In_Storage_Elements 4028 => 4029 Apply_Universal_Integer_Attribute_Checks (N); 4030 4031 -- The following attributes should not appear at this stage, since they 4032 -- have already been handled by the analyzer (and properly rewritten 4033 -- with corresponding values or entities to represent the right values) 4034 4035 when Attribute_Abort_Signal | 4036 Attribute_Address_Size | 4037 Attribute_Base | 4038 Attribute_Class | 4039 Attribute_Default_Bit_Order | 4040 Attribute_Delta | 4041 Attribute_Denorm | 4042 Attribute_Digits | 4043 Attribute_Emax | 4044 Attribute_Epsilon | 4045 Attribute_Has_Discriminants | 4046 Attribute_Large | 4047 Attribute_Machine_Emax | 4048 Attribute_Machine_Emin | 4049 Attribute_Machine_Mantissa | 4050 Attribute_Machine_Overflows | 4051 Attribute_Machine_Radix | 4052 Attribute_Machine_Rounds | 4053 Attribute_Maximum_Alignment | 4054 Attribute_Model_Emin | 4055 Attribute_Model_Epsilon | 4056 Attribute_Model_Mantissa | 4057 Attribute_Model_Small | 4058 Attribute_Modulus | 4059 Attribute_Partition_ID | 4060 Attribute_Range | 4061 Attribute_Safe_Emax | 4062 Attribute_Safe_First | 4063 Attribute_Safe_Large | 4064 Attribute_Safe_Last | 4065 Attribute_Safe_Small | 4066 Attribute_Scale | 4067 Attribute_Signed_Zeros | 4068 Attribute_Small | 4069 Attribute_Storage_Unit | 4070 Attribute_Target_Name | 4071 Attribute_Type_Class | 4072 Attribute_Unconstrained_Array | 4073 Attribute_Universal_Literal_String | 4074 Attribute_Wchar_T_Size | 4075 Attribute_Word_Size => 4076 4077 raise Program_Error; 4078 4079 -- The Asm_Input and Asm_Output attributes are not expanded at this 4080 -- stage, but will be eliminated in the expansion of the Asm call, 4081 -- see Exp_Intr for details. So Gigi will never see these either. 4082 4083 when Attribute_Asm_Input | 4084 Attribute_Asm_Output => 4085 4086 null; 4087 4088 end case; 4089 4090 exception 4091 when RE_Not_Available => 4092 return; 4093 end Expand_N_Attribute_Reference; 4094 4095 ---------------------- 4096 -- Expand_Pred_Succ -- 4097 ---------------------- 4098 4099 -- For typ'Pred (exp), we generate the check 4100 4101 -- [constraint_error when exp = typ'Base'First] 4102 4103 -- Similarly, for typ'Succ (exp), we generate the check 4104 4105 -- [constraint_error when exp = typ'Base'Last] 4106 4107 -- These checks are not generated for modular types, since the proper 4108 -- semantics for Succ and Pred on modular types is to wrap, not raise CE. 4109 4110 procedure Expand_Pred_Succ (N : Node_Id) is 4111 Loc : constant Source_Ptr := Sloc (N); 4112 Cnam : Name_Id; 4113 4114 begin 4115 if Attribute_Name (N) = Name_Pred then 4116 Cnam := Name_First; 4117 else 4118 Cnam := Name_Last; 4119 end if; 4120 4121 Insert_Action (N, 4122 Make_Raise_Constraint_Error (Loc, 4123 Condition => 4124 Make_Op_Eq (Loc, 4125 Left_Opnd => 4126 Duplicate_Subexpr_Move_Checks (First (Expressions (N))), 4127 Right_Opnd => 4128 Make_Attribute_Reference (Loc, 4129 Prefix => 4130 New_Reference_To (Base_Type (Etype (Prefix (N))), Loc), 4131 Attribute_Name => Cnam)), 4132 Reason => CE_Overflow_Check_Failed)); 4133 4134 end Expand_Pred_Succ; 4135 4136 ------------------------ 4137 -- Find_Inherited_TSS -- 4138 ------------------------ 4139 4140 function Find_Inherited_TSS 4141 (Typ : Entity_Id; 4142 Nam : TSS_Name_Type) return Entity_Id 4143 is 4144 Btyp : Entity_Id := Typ; 4145 Proc : Entity_Id; 4146 4147 begin 4148 loop 4149 Btyp := Base_Type (Btyp); 4150 Proc := TSS (Btyp, Nam); 4151 4152 exit when Present (Proc) 4153 or else not Is_Derived_Type (Btyp); 4154 4155 -- If Typ is a derived type, it may inherit attributes from 4156 -- some ancestor. 4157 4158 Btyp := Etype (Btyp); 4159 end loop; 4160 4161 if No (Proc) then 4162 4163 -- If nothing else, use the TSS of the root type 4164 4165 Proc := TSS (Base_Type (Underlying_Type (Typ)), Nam); 4166 end if; 4167 4168 return Proc; 4169 4170 end Find_Inherited_TSS; 4171 4172 ---------------------------- 4173 -- Find_Stream_Subprogram -- 4174 ---------------------------- 4175 4176 function Find_Stream_Subprogram 4177 (Typ : Entity_Id; 4178 Nam : TSS_Name_Type) return Entity_Id is 4179 begin 4180 if Is_Tagged_Type (Typ) 4181 and then Is_Derived_Type (Typ) 4182 then 4183 return Find_Prim_Op (Typ, Nam); 4184 else 4185 return Find_Inherited_TSS (Typ, Nam); 4186 end if; 4187 end Find_Stream_Subprogram; 4188 4189 ----------------------- 4190 -- Get_Index_Subtype -- 4191 ----------------------- 4192 4193 function Get_Index_Subtype (N : Node_Id) return Node_Id is 4194 P_Type : Entity_Id := Etype (Prefix (N)); 4195 Indx : Node_Id; 4196 J : Int; 4197 4198 begin 4199 if Is_Access_Type (P_Type) then 4200 P_Type := Designated_Type (P_Type); 4201 end if; 4202 4203 if No (Expressions (N)) then 4204 J := 1; 4205 else 4206 J := UI_To_Int (Expr_Value (First (Expressions (N)))); 4207 end if; 4208 4209 Indx := First_Index (P_Type); 4210 while J > 1 loop 4211 Next_Index (Indx); 4212 J := J - 1; 4213 end loop; 4214 4215 return Etype (Indx); 4216 end Get_Index_Subtype; 4217 4218 --------------------------------- 4219 -- Is_Constrained_Packed_Array -- 4220 --------------------------------- 4221 4222 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean is 4223 Arr : Entity_Id := Typ; 4224 4225 begin 4226 if Is_Access_Type (Arr) then 4227 Arr := Designated_Type (Arr); 4228 end if; 4229 4230 return Is_Array_Type (Arr) 4231 and then Is_Constrained (Arr) 4232 and then Present (Packed_Array_Type (Arr)); 4233 end Is_Constrained_Packed_Array; 4234 4235end Exp_Attr; 4236