1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Einfo; use Einfo;
29 with Elists; use Elists;
30 with Exp_Atag; use Exp_Atag;
31 with Exp_Ch2; use Exp_Ch2;
32 with Exp_Ch3; use Exp_Ch3;
33 with Exp_Ch6; use Exp_Ch6;
34 with Exp_Ch9; use Exp_Ch9;
35 with Exp_Dist; use Exp_Dist;
36 with Exp_Imgv; use Exp_Imgv;
37 with Exp_Pakd; use Exp_Pakd;
38 with Exp_Strm; use Exp_Strm;
39 with Exp_Tss; use Exp_Tss;
40 with Exp_Util; use Exp_Util;
41 with Exp_VFpt; use Exp_VFpt;
42 with Fname; use Fname;
43 with Freeze; use Freeze;
44 with Gnatvsn; use Gnatvsn;
45 with Itypes; use Itypes;
47 with Namet; use Namet;
48 with Nmake; use Nmake;
49 with Nlists; use Nlists;
51 with Restrict; use Restrict;
52 with Rident; use Rident;
53 with Rtsfind; use Rtsfind;
55 with Sem_Aux; use Sem_Aux;
56 with Sem_Ch6; use Sem_Ch6;
57 with Sem_Ch7; use Sem_Ch7;
58 with Sem_Ch8; use Sem_Ch8;
59 with Sem_Eval; use Sem_Eval;
60 with Sem_Res; use Sem_Res;
61 with Sem_Util; use Sem_Util;
62 with Sinfo; use Sinfo;
63 with Snames; use Snames;
64 with Stand; use Stand;
65 with Stringt; use Stringt;
66 with Targparm; use Targparm;
67 with Tbuild; use Tbuild;
68 with Ttypes; use Ttypes;
69 with Uintp; use Uintp;
70 with Uname; use Uname;
71 with Validsw; use Validsw;
73 package body Exp_Attr is
75 -----------------------
76 -- Local Subprograms --
77 -----------------------
79 procedure Compile_Stream_Body_In_Scope
84 -- The body for a stream subprogram may be generated outside of the scope
85 -- of the type. If the type is fully private, it may depend on the full
86 -- view of other types (e.g. indexes) that are currently private as well.
87 -- We install the declarations of the package in which the type is declared
88 -- before compiling the body in what is its proper environment. The Check
89 -- parameter indicates if checks are to be suppressed for the stream body.
90 -- We suppress checks for array/record reads, since the rule is that these
91 -- are like assignments, out of range values due to uninitialized storage,
92 -- or other invalid values do NOT cause a Constraint_Error to be raised.
94 procedure Expand_Access_To_Protected_Op
98 -- An attribute reference to a protected subprogram is transformed into
99 -- a pair of pointers: one to the object, and one to the operations.
100 -- This expansion is performed for 'Access and for 'Unrestricted_Access.
102 procedure Expand_Fpt_Attribute
107 -- This procedure expands a call to a floating-point attribute function.
108 -- N is the attribute reference node, and Args is a list of arguments to
109 -- be passed to the function call. Pkg identifies the package containing
110 -- the appropriate instantiation of System.Fat_Gen. Float arguments in Args
111 -- have already been converted to the floating-point type for which Pkg was
112 -- instantiated. The Nam argument is the relevant attribute processing
113 -- routine to be called. This is the same as the attribute name, except in
114 -- the Unaligned_Valid case.
116 procedure Expand_Fpt_Attribute_R (N : Node_Id);
117 -- This procedure expands a call to a floating-point attribute function
118 -- that takes a single floating-point argument. The function to be called
119 -- is always the same as the attribute name.
121 procedure Expand_Fpt_Attribute_RI (N : Node_Id);
122 -- This procedure expands a call to a floating-point attribute function
123 -- that takes one floating-point argument and one integer argument. The
124 -- function to be called is always the same as the attribute name.
126 procedure Expand_Fpt_Attribute_RR (N : Node_Id);
127 -- This procedure expands a call to a floating-point attribute function
128 -- that takes two floating-point arguments. The function to be called
129 -- is always the same as the attribute name.
131 procedure Expand_Pred_Succ (N : Node_Id);
132 -- Handles expansion of Pred or Succ attributes for case of non-real
133 -- operand with overflow checking required.
135 function Get_Index_Subtype (N : Node_Id) return Entity_Id;
136 -- Used for Last, Last, and Length, when the prefix is an array type.
137 -- Obtains the corresponding index subtype.
139 procedure Find_Fat_Info
141 Fat_Type : out Entity_Id;
142 Fat_Pkg : out RE_Id);
143 -- Given a floating-point type T, identifies the package containing the
144 -- attributes for this type (returned in Fat_Pkg), and the corresponding
145 -- type for which this package was instantiated from Fat_Gen. Error if T
146 -- is not a floating-point type.
148 function Find_Stream_Subprogram
150 Nam : TSS_Name_Type) return Entity_Id;
151 -- Returns the stream-oriented subprogram attribute for Typ. For tagged
152 -- types, the corresponding primitive operation is looked up, else the
153 -- appropriate TSS from the type itself, or from its closest ancestor
154 -- defining it, is returned. In both cases, inheritance of representation
155 -- aspects is thus taken into account.
157 function Full_Base (T : Entity_Id) return Entity_Id;
158 -- The stream functions need to examine the underlying representation of
159 -- composite types. In some cases T may be non-private but its base type
160 -- is, in which case the function returns the corresponding full view.
162 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id;
163 -- Given a type, find a corresponding stream convert pragma that applies to
164 -- the implementation base type of this type (Typ). If found, return the
165 -- pragma node, otherwise return Empty if no pragma is found.
167 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean;
168 -- Utility for array attributes, returns true on packed constrained
169 -- arrays, and on access to same.
171 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean;
172 -- Returns true iff the given node refers to an attribute call that
173 -- can be expanded directly by the back end and does not need front end
174 -- expansion. Typically used for rounding and truncation attributes that
175 -- appear directly inside a conversion to integer.
177 ----------------------------------
178 -- Compile_Stream_Body_In_Scope --
179 ----------------------------------
181 procedure Compile_Stream_Body_In_Scope
187 Installed : Boolean := False;
188 Scop : constant Entity_Id := Scope (Arr);
189 Curr : constant Entity_Id := Current_Scope;
193 and then not In_Open_Scopes (Scop)
194 and then Ekind (Scop) = E_Package
197 Install_Visible_Declarations (Scop);
198 Install_Private_Declarations (Scop);
201 -- The entities in the package are now visible, but the generated
202 -- stream entity must appear in the current scope (usually an
203 -- enclosing stream function) so that itypes all have their proper
210 Insert_Action (N, Decl);
212 Insert_Action (N, Decl, Suppress => All_Checks);
217 -- Remove extra copy of current scope, and package itself
220 End_Package_Scope (Scop);
222 end Compile_Stream_Body_In_Scope;
224 -----------------------------------
225 -- Expand_Access_To_Protected_Op --
226 -----------------------------------
228 procedure Expand_Access_To_Protected_Op
233 -- The value of the attribute_reference is a record containing two
234 -- fields: an access to the protected object, and an access to the
235 -- subprogram itself. The prefix is a selected component.
237 Loc : constant Source_Ptr := Sloc (N);
239 Btyp : constant Entity_Id := Base_Type (Typ);
242 E_T : constant Entity_Id := Equivalent_Type (Btyp);
243 Acc : constant Entity_Id :=
244 Etype (Next_Component (First_Component (E_T)));
248 function May_Be_External_Call return Boolean;
249 -- If the 'Access is to a local operation, but appears in a context
250 -- where it may lead to a call from outside the object, we must treat
251 -- this as an external call. Clearly we cannot tell without full
252 -- flow analysis, and a subsequent call that uses this 'Access may
253 -- lead to a bounded error (trying to seize locks twice, e.g.). For
254 -- now we treat 'Access as a potential external call if it is an actual
255 -- in a call to an outside subprogram.
257 --------------------------
258 -- May_Be_External_Call --
259 --------------------------
261 function May_Be_External_Call return Boolean is
263 Par : Node_Id := Parent (N);
266 -- Account for the case where the Access attribute is part of a
267 -- named parameter association.
269 if Nkind (Par) = N_Parameter_Association then
273 if Nkind_In (Par, N_Procedure_Call_Statement, N_Function_Call)
274 and then Is_Entity_Name (Name (Par))
276 Subp := Entity (Name (Par));
277 return not In_Open_Scopes (Scope (Subp));
281 end May_Be_External_Call;
283 -- Start of processing for Expand_Access_To_Protected_Op
286 -- Within the body of the protected type, the prefix designates a local
287 -- operation, and the object is the first parameter of the corresponding
288 -- protected body of the current enclosing operation.
290 if Is_Entity_Name (Pref) then
291 if May_Be_External_Call then
293 New_Occurrence_Of (External_Subprogram (Entity (Pref)), Loc);
297 (Protected_Body_Subprogram (Entity (Pref)), Loc);
300 -- Don't traverse the scopes when the attribute occurs within an init
301 -- proc, because we directly use the _init formal of the init proc in
304 Curr := Current_Scope;
305 if not Is_Init_Proc (Curr) then
306 pragma Assert (In_Open_Scopes (Scope (Entity (Pref))));
308 while Scope (Curr) /= Scope (Entity (Pref)) loop
309 Curr := Scope (Curr);
313 -- In case of protected entries the first formal of its Protected_
314 -- Body_Subprogram is the address of the object.
316 if Ekind (Curr) = E_Entry then
320 (Protected_Body_Subprogram (Curr)), Loc);
322 -- If the current scope is an init proc, then use the address of the
323 -- _init formal as the object reference.
325 elsif Is_Init_Proc (Curr) then
327 Make_Attribute_Reference (Loc,
328 Prefix => New_Occurrence_Of (First_Formal (Curr), Loc),
329 Attribute_Name => Name_Address);
331 -- In case of protected subprograms the first formal of its
332 -- Protected_Body_Subprogram is the object and we get its address.
336 Make_Attribute_Reference (Loc,
340 (Protected_Body_Subprogram (Curr)), Loc),
341 Attribute_Name => Name_Address);
344 -- Case where the prefix is not an entity name. Find the
345 -- version of the protected operation to be called from
346 -- outside the protected object.
352 (Entity (Selector_Name (Pref))), Loc);
355 Make_Attribute_Reference (Loc,
356 Prefix => Relocate_Node (Prefix (Pref)),
357 Attribute_Name => Name_Address);
361 Make_Attribute_Reference (Loc,
363 Attribute_Name => Name_Access);
365 -- We set the type of the access reference to the already generated
366 -- access_to_subprogram type, and declare the reference analyzed, to
367 -- prevent further expansion when the enclosing aggregate is analyzed.
369 Set_Etype (Sub_Ref, Acc);
370 Set_Analyzed (Sub_Ref);
374 Expressions => New_List (Obj_Ref, Sub_Ref));
376 -- Sub_Ref has been marked as analyzed, but we still need to make sure
377 -- Sub is correctly frozen.
379 Freeze_Before (N, Entity (Sub));
382 Analyze_And_Resolve (N, E_T);
384 -- For subsequent analysis, the node must retain its type. The backend
385 -- will replace it with the equivalent type where needed.
388 end Expand_Access_To_Protected_Op;
390 --------------------------
391 -- Expand_Fpt_Attribute --
392 --------------------------
394 procedure Expand_Fpt_Attribute
400 Loc : constant Source_Ptr := Sloc (N);
401 Typ : constant Entity_Id := Etype (N);
405 -- The function name is the selected component Attr_xxx.yyy where
406 -- Attr_xxx is the package name, and yyy is the argument Nam.
408 -- Note: it would be more usual to have separate RE entries for each
409 -- of the entities in the Fat packages, but first they have identical
410 -- names (so we would have to have lots of renaming declarations to
411 -- meet the normal RE rule of separate names for all runtime entities),
412 -- and second there would be an awful lot of them!
415 Make_Selected_Component (Loc,
416 Prefix => New_Reference_To (RTE (Pkg), Loc),
417 Selector_Name => Make_Identifier (Loc, Nam));
419 -- The generated call is given the provided set of parameters, and then
420 -- wrapped in a conversion which converts the result to the target type
421 -- We use the base type as the target because a range check may be
425 Unchecked_Convert_To (Base_Type (Etype (N)),
426 Make_Function_Call (Loc,
428 Parameter_Associations => Args)));
430 Analyze_And_Resolve (N, Typ);
431 end Expand_Fpt_Attribute;
433 ----------------------------
434 -- Expand_Fpt_Attribute_R --
435 ----------------------------
437 -- The single argument is converted to its root type to call the
438 -- appropriate runtime function, with the actual call being built
439 -- by Expand_Fpt_Attribute
441 procedure Expand_Fpt_Attribute_R (N : Node_Id) is
442 E1 : constant Node_Id := First (Expressions (N));
446 Find_Fat_Info (Etype (E1), Ftp, Pkg);
448 (N, Pkg, Attribute_Name (N),
449 New_List (Unchecked_Convert_To (Ftp, Relocate_Node (E1))));
450 end Expand_Fpt_Attribute_R;
452 -----------------------------
453 -- Expand_Fpt_Attribute_RI --
454 -----------------------------
456 -- The first argument is converted to its root type and the second
457 -- argument is converted to standard long long integer to call the
458 -- appropriate runtime function, with the actual call being built
459 -- by Expand_Fpt_Attribute
461 procedure Expand_Fpt_Attribute_RI (N : Node_Id) is
462 E1 : constant Node_Id := First (Expressions (N));
465 E2 : constant Node_Id := Next (E1);
467 Find_Fat_Info (Etype (E1), Ftp, Pkg);
469 (N, Pkg, Attribute_Name (N),
471 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
472 Unchecked_Convert_To (Standard_Integer, Relocate_Node (E2))));
473 end Expand_Fpt_Attribute_RI;
475 -----------------------------
476 -- Expand_Fpt_Attribute_RR --
477 -----------------------------
479 -- The two arguments are converted to their root types to call the
480 -- appropriate runtime function, with the actual call being built
481 -- by Expand_Fpt_Attribute
483 procedure Expand_Fpt_Attribute_RR (N : Node_Id) is
484 E1 : constant Node_Id := First (Expressions (N));
487 E2 : constant Node_Id := Next (E1);
489 Find_Fat_Info (Etype (E1), Ftp, Pkg);
491 (N, Pkg, Attribute_Name (N),
493 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
494 Unchecked_Convert_To (Ftp, Relocate_Node (E2))));
495 end Expand_Fpt_Attribute_RR;
497 ----------------------------------
498 -- Expand_N_Attribute_Reference --
499 ----------------------------------
501 procedure Expand_N_Attribute_Reference (N : Node_Id) is
502 Loc : constant Source_Ptr := Sloc (N);
503 Typ : constant Entity_Id := Etype (N);
504 Btyp : constant Entity_Id := Base_Type (Typ);
505 Pref : constant Node_Id := Prefix (N);
506 Ptyp : constant Entity_Id := Etype (Pref);
507 Exprs : constant List_Id := Expressions (N);
508 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
510 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id);
511 -- Rewrites a stream attribute for Read, Write or Output with the
512 -- procedure call. Pname is the entity for the procedure to call.
514 ------------------------------
515 -- Rewrite_Stream_Proc_Call --
516 ------------------------------
518 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id) is
519 Item : constant Node_Id := Next (First (Exprs));
520 Formal : constant Entity_Id := Next_Formal (First_Formal (Pname));
521 Formal_Typ : constant Entity_Id := Etype (Formal);
522 Is_Written : constant Boolean := (Ekind (Formal) /= E_In_Parameter);
525 -- The expansion depends on Item, the second actual, which is
526 -- the object being streamed in or out.
528 -- If the item is a component of a packed array type, and
529 -- a conversion is needed on exit, we introduce a temporary to
530 -- hold the value, because otherwise the packed reference will
531 -- not be properly expanded.
533 if Nkind (Item) = N_Indexed_Component
534 and then Is_Packed (Base_Type (Etype (Prefix (Item))))
535 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
539 Temp : constant Entity_Id := Make_Temporary (Loc, 'V');
545 Make_Object_Declaration (Loc,
546 Defining_Identifier => Temp,
548 New_Occurrence_Of (Formal_Typ, Loc));
549 Set_Etype (Temp, Formal_Typ);
552 Make_Assignment_Statement (Loc,
553 Name => New_Copy_Tree (Item),
556 (Etype (Item), New_Occurrence_Of (Temp, Loc)));
558 Rewrite (Item, New_Occurrence_Of (Temp, Loc));
562 Make_Procedure_Call_Statement (Loc,
563 Name => New_Occurrence_Of (Pname, Loc),
564 Parameter_Associations => Exprs),
567 Rewrite (N, Make_Null_Statement (Loc));
572 -- For the class-wide dispatching cases, and for cases in which
573 -- the base type of the second argument matches the base type of
574 -- the corresponding formal parameter (that is to say the stream
575 -- operation is not inherited), we are all set, and can use the
576 -- argument unchanged.
578 -- For all other cases we do an unchecked conversion of the second
579 -- parameter to the type of the formal of the procedure we are
580 -- calling. This deals with the private type cases, and with going
581 -- to the root type as required in elementary type case.
583 if not Is_Class_Wide_Type (Entity (Pref))
584 and then not Is_Class_Wide_Type (Etype (Item))
585 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
588 Unchecked_Convert_To (Formal_Typ, Relocate_Node (Item)));
590 -- For untagged derived types set Assignment_OK, to prevent
591 -- copies from being created when the unchecked conversion
592 -- is expanded (which would happen in Remove_Side_Effects
593 -- if Expand_N_Unchecked_Conversion were allowed to call
594 -- Force_Evaluation). The copy could violate Ada semantics
595 -- in cases such as an actual that is an out parameter.
596 -- Note that this approach is also used in exp_ch7 for calls
597 -- to controlled type operations to prevent problems with
598 -- actuals wrapped in unchecked conversions.
600 if Is_Untagged_Derivation (Etype (Expression (Item))) then
601 Set_Assignment_OK (Item);
605 -- The stream operation to call maybe a renaming created by
606 -- an attribute definition clause, and may not be frozen yet.
607 -- Ensure that it has the necessary extra formals.
609 if not Is_Frozen (Pname) then
610 Create_Extra_Formals (Pname);
613 -- And now rewrite the call
616 Make_Procedure_Call_Statement (Loc,
617 Name => New_Occurrence_Of (Pname, Loc),
618 Parameter_Associations => Exprs));
621 end Rewrite_Stream_Proc_Call;
623 -- Start of processing for Expand_N_Attribute_Reference
626 -- Do required validity checking, if enabled. Do not apply check to
627 -- output parameters of an Asm instruction, since the value of this
628 -- is not set till after the attribute has been elaborated, and do
629 -- not apply the check to the arguments of a 'Read or 'Input attribute
630 -- reference since the scalar argument is an OUT scalar.
632 if Validity_Checks_On and then Validity_Check_Operands
633 and then Id /= Attribute_Asm_Output
634 and then Id /= Attribute_Read
635 and then Id /= Attribute_Input
640 Expr := First (Expressions (N));
641 while Present (Expr) loop
648 -- Ada 2005 (AI-318-02): If attribute prefix is a call to a build-in-
649 -- place function, then a temporary return object needs to be created
650 -- and access to it must be passed to the function. Currently we limit
651 -- such functions to those with inherently limited result subtypes, but
652 -- eventually we plan to expand the functions that are treated as
653 -- build-in-place to include other composite result types.
655 if Ada_Version >= Ada_2005
656 and then Is_Build_In_Place_Function_Call (Pref)
658 Make_Build_In_Place_Call_In_Anonymous_Context (Pref);
661 -- If prefix is a protected type name, this is a reference to the
662 -- current instance of the type. For a component definition, nothing
663 -- to do (expansion will occur in the init proc). In other contexts,
664 -- rewrite into reference to current instance.
666 if Is_Protected_Self_Reference (Pref)
668 (Nkind_In (Parent (N), N_Index_Or_Discriminant_Constraint,
669 N_Discriminant_Association)
670 and then Nkind (Parent (Parent (Parent (Parent (N))))) =
671 N_Component_Definition)
673 Rewrite (Pref, Concurrent_Ref (Pref));
677 -- Remaining processing depends on specific attribute
685 when Attribute_Access |
686 Attribute_Unchecked_Access |
687 Attribute_Unrestricted_Access =>
689 Access_Cases : declare
690 Ref_Object : constant Node_Id := Get_Referenced_Object (Pref);
691 Btyp_DDT : Entity_Id;
693 function Enclosing_Object (N : Node_Id) return Node_Id;
694 -- If N denotes a compound name (selected component, indexed
695 -- component, or slice), returns the name of the outermost such
696 -- enclosing object. Otherwise returns N. If the object is a
697 -- renaming, then the renamed object is returned.
699 ----------------------
700 -- Enclosing_Object --
701 ----------------------
703 function Enclosing_Object (N : Node_Id) return Node_Id is
708 while Nkind_In (Obj_Name, N_Selected_Component,
712 Obj_Name := Prefix (Obj_Name);
715 return Get_Referenced_Object (Obj_Name);
716 end Enclosing_Object;
718 -- Local declarations
720 Enc_Object : constant Node_Id := Enclosing_Object (Ref_Object);
722 -- Start of processing for Access_Cases
725 Btyp_DDT := Designated_Type (Btyp);
727 -- Handle designated types that come from the limited view
729 if Ekind (Btyp_DDT) = E_Incomplete_Type
730 and then From_With_Type (Btyp_DDT)
731 and then Present (Non_Limited_View (Btyp_DDT))
733 Btyp_DDT := Non_Limited_View (Btyp_DDT);
735 elsif Is_Class_Wide_Type (Btyp_DDT)
736 and then Ekind (Etype (Btyp_DDT)) = E_Incomplete_Type
737 and then From_With_Type (Etype (Btyp_DDT))
738 and then Present (Non_Limited_View (Etype (Btyp_DDT)))
739 and then Present (Class_Wide_Type
740 (Non_Limited_View (Etype (Btyp_DDT))))
743 Class_Wide_Type (Non_Limited_View (Etype (Btyp_DDT)));
746 -- In order to improve the text of error messages, the designated
747 -- type of access-to-subprogram itypes is set by the semantics as
748 -- the associated subprogram entity (see sem_attr). Now we replace
749 -- such node with the proper E_Subprogram_Type itype.
751 if Id = Attribute_Unrestricted_Access
752 and then Is_Subprogram (Directly_Designated_Type (Typ))
754 -- The following conditions ensure that this special management
755 -- is done only for "Address!(Prim'Unrestricted_Access)" nodes.
756 -- At this stage other cases in which the designated type is
757 -- still a subprogram (instead of an E_Subprogram_Type) are
758 -- wrong because the semantics must have overridden the type of
759 -- the node with the type imposed by the context.
761 if Nkind (Parent (N)) = N_Unchecked_Type_Conversion
762 and then Etype (Parent (N)) = RTE (RE_Prim_Ptr)
764 Set_Etype (N, RTE (RE_Prim_Ptr));
768 Subp : constant Entity_Id :=
769 Directly_Designated_Type (Typ);
771 Extra : Entity_Id := Empty;
772 New_Formal : Entity_Id;
773 Old_Formal : Entity_Id := First_Formal (Subp);
774 Subp_Typ : Entity_Id;
777 Subp_Typ := Create_Itype (E_Subprogram_Type, N);
778 Set_Etype (Subp_Typ, Etype (Subp));
779 Set_Returns_By_Ref (Subp_Typ, Returns_By_Ref (Subp));
781 if Present (Old_Formal) then
782 New_Formal := New_Copy (Old_Formal);
783 Set_First_Entity (Subp_Typ, New_Formal);
786 Set_Scope (New_Formal, Subp_Typ);
787 Etyp := Etype (New_Formal);
789 -- Handle itypes. There is no need to duplicate
790 -- here the itypes associated with record types
791 -- (i.e the implicit full view of private types).
794 and then Ekind (Base_Type (Etyp)) /= E_Record_Type
796 Extra := New_Copy (Etyp);
797 Set_Parent (Extra, New_Formal);
798 Set_Etype (New_Formal, Extra);
799 Set_Scope (Extra, Subp_Typ);
803 Next_Formal (Old_Formal);
804 exit when No (Old_Formal);
806 Set_Next_Entity (New_Formal,
807 New_Copy (Old_Formal));
808 Next_Entity (New_Formal);
811 Set_Next_Entity (New_Formal, Empty);
812 Set_Last_Entity (Subp_Typ, Extra);
815 -- Now that the explicit formals have been duplicated,
816 -- any extra formals needed by the subprogram must be
819 if Present (Extra) then
820 Set_Extra_Formal (Extra, Empty);
823 Create_Extra_Formals (Subp_Typ);
824 Set_Directly_Designated_Type (Typ, Subp_Typ);
829 if Is_Access_Protected_Subprogram_Type (Btyp) then
830 Expand_Access_To_Protected_Op (N, Pref, Typ);
832 -- If prefix is a type name, this is a reference to the current
833 -- instance of the type, within its initialization procedure.
835 elsif Is_Entity_Name (Pref)
836 and then Is_Type (Entity (Pref))
843 -- If the current instance name denotes a task type, then
844 -- the access attribute is rewritten to be the name of the
845 -- "_task" parameter associated with the task type's task
846 -- procedure. An unchecked conversion is applied to ensure
847 -- a type match in cases of expander-generated calls (e.g.
850 if Is_Task_Type (Entity (Pref)) then
852 First_Entity (Get_Task_Body_Procedure (Entity (Pref)));
853 while Present (Formal) loop
854 exit when Chars (Formal) = Name_uTask;
855 Next_Entity (Formal);
858 pragma Assert (Present (Formal));
861 Unchecked_Convert_To (Typ,
862 New_Occurrence_Of (Formal, Loc)));
865 -- The expression must appear in a default expression,
866 -- (which in the initialization procedure is the
867 -- right-hand side of an assignment), and not in a
868 -- discriminant constraint.
872 while Present (Par) loop
873 exit when Nkind (Par) = N_Assignment_Statement;
875 if Nkind (Par) = N_Component_Declaration then
882 if Present (Par) then
884 Make_Attribute_Reference (Loc,
885 Prefix => Make_Identifier (Loc, Name_uInit),
886 Attribute_Name => Attribute_Name (N)));
888 Analyze_And_Resolve (N, Typ);
893 -- If the prefix of an Access attribute is a dereference of an
894 -- access parameter (or a renaming of such a dereference, or a
895 -- subcomponent of such a dereference) and the context is a
896 -- general access type (including the type of an object or
897 -- component with an access_definition, but not the anonymous
898 -- type of an access parameter or access discriminant), then
899 -- apply an accessibility check to the access parameter. We used
900 -- to rewrite the access parameter as a type conversion, but that
901 -- could only be done if the immediate prefix of the Access
902 -- attribute was the dereference, and didn't handle cases where
903 -- the attribute is applied to a subcomponent of the dereference,
904 -- since there's generally no available, appropriate access type
905 -- to convert to in that case. The attribute is passed as the
906 -- point to insert the check, because the access parameter may
907 -- come from a renaming, possibly in a different scope, and the
908 -- check must be associated with the attribute itself.
910 elsif Id = Attribute_Access
911 and then Nkind (Enc_Object) = N_Explicit_Dereference
912 and then Is_Entity_Name (Prefix (Enc_Object))
913 and then (Ekind (Btyp) = E_General_Access_Type
914 or else Is_Local_Anonymous_Access (Btyp))
915 and then Ekind (Entity (Prefix (Enc_Object))) in Formal_Kind
916 and then Ekind (Etype (Entity (Prefix (Enc_Object))))
917 = E_Anonymous_Access_Type
918 and then Present (Extra_Accessibility
919 (Entity (Prefix (Enc_Object))))
921 Apply_Accessibility_Check (Prefix (Enc_Object), Typ, N);
923 -- Ada 2005 (AI-251): If the designated type is an interface we
924 -- add an implicit conversion to force the displacement of the
925 -- pointer to reference the secondary dispatch table.
927 elsif Is_Interface (Btyp_DDT)
928 and then (Comes_From_Source (N)
929 or else Comes_From_Source (Ref_Object)
930 or else (Nkind (Ref_Object) in N_Has_Chars
931 and then Chars (Ref_Object) = Name_uInit))
933 if Nkind (Ref_Object) /= N_Explicit_Dereference then
935 -- No implicit conversion required if types match, or if
936 -- the prefix is the class_wide_type of the interface. In
937 -- either case passing an object of the interface type has
938 -- already set the pointer correctly.
940 if Btyp_DDT = Etype (Ref_Object)
941 or else (Is_Class_Wide_Type (Etype (Ref_Object))
943 Class_Wide_Type (Btyp_DDT) = Etype (Ref_Object))
949 Convert_To (Btyp_DDT,
950 New_Copy_Tree (Prefix (N))));
952 Analyze_And_Resolve (Prefix (N), Btyp_DDT);
955 -- When the object is an explicit dereference, convert the
956 -- dereference's prefix.
960 Obj_DDT : constant Entity_Id :=
962 (Directly_Designated_Type
963 (Etype (Prefix (Ref_Object))));
965 -- No implicit conversion required if designated types
968 if Obj_DDT /= Btyp_DDT
969 and then not (Is_Class_Wide_Type (Obj_DDT)
970 and then Etype (Obj_DDT) = Btyp_DDT)
974 New_Copy_Tree (Prefix (Ref_Object))));
975 Analyze_And_Resolve (N, Typ);
986 -- Transforms 'Adjacent into a call to the floating-point attribute
987 -- function Adjacent in Fat_xxx (where xxx is the root type)
989 when Attribute_Adjacent =>
990 Expand_Fpt_Attribute_RR (N);
996 when Attribute_Address => Address : declare
997 Task_Proc : Entity_Id;
1000 -- If the prefix is a task or a task type, the useful address is that
1001 -- of the procedure for the task body, i.e. the actual program unit.
1002 -- We replace the original entity with that of the procedure.
1004 if Is_Entity_Name (Pref)
1005 and then Is_Task_Type (Entity (Pref))
1007 Task_Proc := Next_Entity (Root_Type (Ptyp));
1009 while Present (Task_Proc) loop
1010 exit when Ekind (Task_Proc) = E_Procedure
1011 and then Etype (First_Formal (Task_Proc)) =
1012 Corresponding_Record_Type (Ptyp);
1013 Next_Entity (Task_Proc);
1016 if Present (Task_Proc) then
1017 Set_Entity (Pref, Task_Proc);
1018 Set_Etype (Pref, Etype (Task_Proc));
1021 -- Similarly, the address of a protected operation is the address
1022 -- of the corresponding protected body, regardless of the protected
1023 -- object from which it is selected.
1025 elsif Nkind (Pref) = N_Selected_Component
1026 and then Is_Subprogram (Entity (Selector_Name (Pref)))
1027 and then Is_Protected_Type (Scope (Entity (Selector_Name (Pref))))
1031 External_Subprogram (Entity (Selector_Name (Pref))), Loc));
1033 elsif Nkind (Pref) = N_Explicit_Dereference
1034 and then Ekind (Ptyp) = E_Subprogram_Type
1035 and then Convention (Ptyp) = Convention_Protected
1037 -- The prefix is be a dereference of an access_to_protected_
1038 -- subprogram. The desired address is the second component of
1039 -- the record that represents the access.
1042 Addr : constant Entity_Id := Etype (N);
1043 Ptr : constant Node_Id := Prefix (Pref);
1044 T : constant Entity_Id :=
1045 Equivalent_Type (Base_Type (Etype (Ptr)));
1049 Unchecked_Convert_To (Addr,
1050 Make_Selected_Component (Loc,
1051 Prefix => Unchecked_Convert_To (T, Ptr),
1052 Selector_Name => New_Occurrence_Of (
1053 Next_Entity (First_Entity (T)), Loc))));
1055 Analyze_And_Resolve (N, Addr);
1058 -- Ada 2005 (AI-251): Class-wide interface objects are always
1059 -- "displaced" to reference the tag associated with the interface
1060 -- type. In order to obtain the real address of such objects we
1061 -- generate a call to a run-time subprogram that returns the base
1062 -- address of the object.
1064 -- This processing is not needed in the VM case, where dispatching
1065 -- issues are taken care of by the virtual machine.
1067 elsif Is_Class_Wide_Type (Ptyp)
1068 and then Is_Interface (Ptyp)
1069 and then Tagged_Type_Expansion
1070 and then not (Nkind (Pref) in N_Has_Entity
1071 and then Is_Subprogram (Entity (Pref)))
1074 Make_Function_Call (Loc,
1075 Name => New_Reference_To (RTE (RE_Base_Address), Loc),
1076 Parameter_Associations => New_List (
1077 Relocate_Node (N))));
1082 -- Deal with packed array reference, other cases are handled by
1085 if Involves_Packed_Array_Reference (Pref) then
1086 Expand_Packed_Address_Reference (N);
1094 when Attribute_Alignment => Alignment : declare
1098 -- For class-wide types, X'Class'Alignment is transformed into a
1099 -- direct reference to the Alignment of the class type, so that the
1100 -- back end does not have to deal with the X'Class'Alignment
1103 if Is_Entity_Name (Pref)
1104 and then Is_Class_Wide_Type (Entity (Pref))
1106 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
1109 -- For x'Alignment applied to an object of a class wide type,
1110 -- transform X'Alignment into a call to the predefined primitive
1111 -- operation _Alignment applied to X.
1113 elsif Is_Class_Wide_Type (Ptyp) then
1115 -- No need to do anything else compiling under restriction
1116 -- No_Dispatching_Calls. During the semantic analysis we
1117 -- already notified such violation.
1119 if Restriction_Active (No_Dispatching_Calls) then
1124 Make_Function_Call (Loc,
1125 Name => New_Reference_To
1126 (Find_Prim_Op (Ptyp, Name_uAlignment), Loc),
1127 Parameter_Associations => New_List (Pref));
1129 if Typ /= Standard_Integer then
1131 -- The context is a specific integer type with which the
1132 -- original attribute was compatible. The function has a
1133 -- specific type as well, so to preserve the compatibility
1134 -- we must convert explicitly.
1136 New_Node := Convert_To (Typ, New_Node);
1139 Rewrite (N, New_Node);
1140 Analyze_And_Resolve (N, Typ);
1143 -- For all other cases, we just have to deal with the case of
1144 -- the fact that the result can be universal.
1147 Apply_Universal_Integer_Attribute_Checks (N);
1155 when Attribute_AST_Entry => AST_Entry : declare
1160 Entry_Ref : Node_Id;
1161 -- The reference to the entry or entry family
1164 -- The index expression for an entry family reference, or
1165 -- the Empty if Entry_Ref references a simple entry.
1168 if Nkind (Pref) = N_Indexed_Component then
1169 Entry_Ref := Prefix (Pref);
1170 Index := First (Expressions (Pref));
1176 -- Get expression for Task_Id and the entry entity
1178 if Nkind (Entry_Ref) = N_Selected_Component then
1180 Make_Attribute_Reference (Loc,
1181 Attribute_Name => Name_Identity,
1182 Prefix => Prefix (Entry_Ref));
1184 Ttyp := Etype (Prefix (Entry_Ref));
1185 Eent := Entity (Selector_Name (Entry_Ref));
1189 Make_Function_Call (Loc,
1190 Name => New_Occurrence_Of (RTE (RE_Current_Task), Loc));
1192 Eent := Entity (Entry_Ref);
1194 -- We have to find the enclosing task to get the task type
1195 -- There must be one, since we already validated this earlier
1197 Ttyp := Current_Scope;
1198 while not Is_Task_Type (Ttyp) loop
1199 Ttyp := Scope (Ttyp);
1203 -- Now rewrite the attribute with a call to Create_AST_Handler
1206 Make_Function_Call (Loc,
1207 Name => New_Occurrence_Of (RTE (RE_Create_AST_Handler), Loc),
1208 Parameter_Associations => New_List (
1210 Entry_Index_Expression (Loc, Eent, Index, Ttyp))));
1212 Analyze_And_Resolve (N, RTE (RE_AST_Handler));
1219 -- We compute this if a packed array reference was present, otherwise we
1220 -- leave the computation up to the back end.
1222 when Attribute_Bit =>
1223 if Involves_Packed_Array_Reference (Pref) then
1224 Expand_Packed_Bit_Reference (N);
1226 Apply_Universal_Integer_Attribute_Checks (N);
1233 -- We compute this if a component clause was present, otherwise we leave
1234 -- the computation up to the back end, since we don't know what layout
1237 -- Note that the attribute can apply to a naked record component
1238 -- in generated code (i.e. the prefix is an identifier that
1239 -- references the component or discriminant entity).
1241 when Attribute_Bit_Position => Bit_Position : declare
1245 if Nkind (Pref) = N_Identifier then
1246 CE := Entity (Pref);
1248 CE := Entity (Selector_Name (Pref));
1251 if Known_Static_Component_Bit_Offset (CE) then
1253 Make_Integer_Literal (Loc,
1254 Intval => Component_Bit_Offset (CE)));
1255 Analyze_And_Resolve (N, Typ);
1258 Apply_Universal_Integer_Attribute_Checks (N);
1266 -- A reference to P'Body_Version or P'Version is expanded to
1269 -- pragma Import (C, Vnn, "uuuuT");
1271 -- Get_Version_String (Vnn)
1273 -- where uuuu is the unit name (dots replaced by double underscore)
1274 -- and T is B for the cases of Body_Version, or Version applied to a
1275 -- subprogram acting as its own spec, and S for Version applied to a
1276 -- subprogram spec or package. This sequence of code references the
1277 -- unsigned constant created in the main program by the binder.
1279 -- A special exception occurs for Standard, where the string returned
1280 -- is a copy of the library string in gnatvsn.ads.
1282 when Attribute_Body_Version | Attribute_Version => Version : declare
1283 E : constant Entity_Id := Make_Temporary (Loc, 'V');
1288 -- If not library unit, get to containing library unit
1290 Pent := Entity (Pref);
1291 while Pent /= Standard_Standard
1292 and then Scope (Pent) /= Standard_Standard
1293 and then not Is_Child_Unit (Pent)
1295 Pent := Scope (Pent);
1298 -- Special case Standard and Standard.ASCII
1300 if Pent = Standard_Standard or else Pent = Standard_ASCII then
1302 Make_String_Literal (Loc,
1303 Strval => Verbose_Library_Version));
1308 -- Build required string constant
1310 Get_Name_String (Get_Unit_Name (Pent));
1313 for J in 1 .. Name_Len - 2 loop
1314 if Name_Buffer (J) = '.' then
1315 Store_String_Chars ("__");
1317 Store_String_Char (Get_Char_Code (Name_Buffer (J)));
1321 -- Case of subprogram acting as its own spec, always use body
1323 if Nkind (Declaration_Node (Pent)) in N_Subprogram_Specification
1324 and then Nkind (Parent (Declaration_Node (Pent))) =
1326 and then Acts_As_Spec (Parent (Declaration_Node (Pent)))
1328 Store_String_Chars ("B");
1330 -- Case of no body present, always use spec
1332 elsif not Unit_Requires_Body (Pent) then
1333 Store_String_Chars ("S");
1335 -- Otherwise use B for Body_Version, S for spec
1337 elsif Id = Attribute_Body_Version then
1338 Store_String_Chars ("B");
1340 Store_String_Chars ("S");
1344 Lib.Version_Referenced (S);
1346 -- Insert the object declaration
1348 Insert_Actions (N, New_List (
1349 Make_Object_Declaration (Loc,
1350 Defining_Identifier => E,
1351 Object_Definition =>
1352 New_Occurrence_Of (RTE (RE_Unsigned), Loc))));
1354 -- Set entity as imported with correct external name
1356 Set_Is_Imported (E);
1357 Set_Interface_Name (E, Make_String_Literal (Loc, S));
1359 -- Set entity as internal to ensure proper Sprint output of its
1360 -- implicit importation.
1362 Set_Is_Internal (E);
1364 -- And now rewrite original reference
1367 Make_Function_Call (Loc,
1368 Name => New_Reference_To (RTE (RE_Get_Version_String), Loc),
1369 Parameter_Associations => New_List (
1370 New_Occurrence_Of (E, Loc))));
1373 Analyze_And_Resolve (N, RTE (RE_Version_String));
1380 -- Transforms 'Ceiling into a call to the floating-point attribute
1381 -- function Ceiling in Fat_xxx (where xxx is the root type)
1383 when Attribute_Ceiling =>
1384 Expand_Fpt_Attribute_R (N);
1390 -- Transforms 'Callable attribute into a call to the Callable function
1392 when Attribute_Callable => Callable :
1394 -- We have an object of a task interface class-wide type as a prefix
1395 -- to Callable. Generate:
1396 -- callable (Task_Id (Pref._disp_get_task_id));
1398 if Ada_Version >= Ada_2005
1399 and then Ekind (Ptyp) = E_Class_Wide_Type
1400 and then Is_Interface (Ptyp)
1401 and then Is_Task_Interface (Ptyp)
1404 Make_Function_Call (Loc,
1406 New_Reference_To (RTE (RE_Callable), Loc),
1407 Parameter_Associations => New_List (
1408 Make_Unchecked_Type_Conversion (Loc,
1410 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
1412 Make_Selected_Component (Loc,
1414 New_Copy_Tree (Pref),
1416 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
1420 Build_Call_With_Task (Pref, RTE (RE_Callable)));
1423 Analyze_And_Resolve (N, Standard_Boolean);
1430 -- Transforms 'Caller attribute into a call to either the
1431 -- Task_Entry_Caller or the Protected_Entry_Caller function.
1433 when Attribute_Caller => Caller : declare
1434 Id_Kind : constant Entity_Id := RTE (RO_AT_Task_Id);
1435 Ent : constant Entity_Id := Entity (Pref);
1436 Conctype : constant Entity_Id := Scope (Ent);
1437 Nest_Depth : Integer := 0;
1444 if Is_Protected_Type (Conctype) then
1445 case Corresponding_Runtime_Package (Conctype) is
1446 when System_Tasking_Protected_Objects_Entries =>
1449 (RTE (RE_Protected_Entry_Caller), Loc);
1451 when System_Tasking_Protected_Objects_Single_Entry =>
1454 (RTE (RE_Protected_Single_Entry_Caller), Loc);
1457 raise Program_Error;
1461 Unchecked_Convert_To (Id_Kind,
1462 Make_Function_Call (Loc,
1464 Parameter_Associations => New_List (
1466 (Find_Protection_Object (Current_Scope), Loc)))));
1471 -- Determine the nesting depth of the E'Caller attribute, that
1472 -- is, how many accept statements are nested within the accept
1473 -- statement for E at the point of E'Caller. The runtime uses
1474 -- this depth to find the specified entry call.
1476 for J in reverse 0 .. Scope_Stack.Last loop
1477 S := Scope_Stack.Table (J).Entity;
1479 -- We should not reach the scope of the entry, as it should
1480 -- already have been checked in Sem_Attr that this attribute
1481 -- reference is within a matching accept statement.
1483 pragma Assert (S /= Conctype);
1488 elsif Is_Entry (S) then
1489 Nest_Depth := Nest_Depth + 1;
1494 Unchecked_Convert_To (Id_Kind,
1495 Make_Function_Call (Loc,
1497 New_Reference_To (RTE (RE_Task_Entry_Caller), Loc),
1498 Parameter_Associations => New_List (
1499 Make_Integer_Literal (Loc,
1500 Intval => Int (Nest_Depth))))));
1503 Analyze_And_Resolve (N, Id_Kind);
1510 -- Transforms 'Compose into a call to the floating-point attribute
1511 -- function Compose in Fat_xxx (where xxx is the root type)
1513 -- Note: we strictly should have special code here to deal with the
1514 -- case of absurdly negative arguments (less than Integer'First)
1515 -- which will return a (signed) zero value, but it hardly seems
1516 -- worth the effort. Absurdly large positive arguments will raise
1517 -- constraint error which is fine.
1519 when Attribute_Compose =>
1520 Expand_Fpt_Attribute_RI (N);
1526 when Attribute_Constrained => Constrained : declare
1527 Formal_Ent : constant Entity_Id := Param_Entity (Pref);
1529 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean;
1530 -- Ada 2005 (AI-363): Returns True if the object name Obj denotes a
1531 -- view of an aliased object whose subtype is constrained.
1533 ---------------------------------
1534 -- Is_Constrained_Aliased_View --
1535 ---------------------------------
1537 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean is
1541 if Is_Entity_Name (Obj) then
1544 if Present (Renamed_Object (E)) then
1545 return Is_Constrained_Aliased_View (Renamed_Object (E));
1547 return Is_Aliased (E) and then Is_Constrained (Etype (E));
1551 return Is_Aliased_View (Obj)
1553 (Is_Constrained (Etype (Obj))
1554 or else (Nkind (Obj) = N_Explicit_Dereference
1556 not Has_Constrained_Partial_View
1557 (Base_Type (Etype (Obj)))));
1559 end Is_Constrained_Aliased_View;
1561 -- Start of processing for Constrained
1564 -- Reference to a parameter where the value is passed as an extra
1565 -- actual, corresponding to the extra formal referenced by the
1566 -- Extra_Constrained field of the corresponding formal. If this
1567 -- is an entry in-parameter, it is replaced by a constant renaming
1568 -- for which Extra_Constrained is never created.
1570 if Present (Formal_Ent)
1571 and then Ekind (Formal_Ent) /= E_Constant
1572 and then Present (Extra_Constrained (Formal_Ent))
1576 (Extra_Constrained (Formal_Ent), Sloc (N)));
1578 -- For variables with a Extra_Constrained field, we use the
1579 -- corresponding entity.
1581 elsif Nkind (Pref) = N_Identifier
1582 and then Ekind (Entity (Pref)) = E_Variable
1583 and then Present (Extra_Constrained (Entity (Pref)))
1587 (Extra_Constrained (Entity (Pref)), Sloc (N)));
1589 -- For all other entity names, we can tell at compile time
1591 elsif Is_Entity_Name (Pref) then
1593 Ent : constant Entity_Id := Entity (Pref);
1597 -- (RM J.4) obsolescent cases
1599 if Is_Type (Ent) then
1603 if Is_Private_Type (Ent) then
1604 Res := not Has_Discriminants (Ent)
1605 or else Is_Constrained (Ent);
1607 -- It not a private type, must be a generic actual type
1608 -- that corresponded to a private type. We know that this
1609 -- correspondence holds, since otherwise the reference
1610 -- within the generic template would have been illegal.
1613 if Is_Composite_Type (Underlying_Type (Ent)) then
1614 Res := Is_Constrained (Ent);
1620 -- If the prefix is not a variable or is aliased, then
1621 -- definitely true; if it's a formal parameter without an
1622 -- associated extra formal, then treat it as constrained.
1624 -- Ada 2005 (AI-363): An aliased prefix must be known to be
1625 -- constrained in order to set the attribute to True.
1627 elsif not Is_Variable (Pref)
1628 or else Present (Formal_Ent)
1629 or else (Ada_Version < Ada_2005
1630 and then Is_Aliased_View (Pref))
1631 or else (Ada_Version >= Ada_2005
1632 and then Is_Constrained_Aliased_View (Pref))
1636 -- Variable case, look at type to see if it is constrained.
1637 -- Note that the one case where this is not accurate (the
1638 -- procedure formal case), has been handled above.
1640 -- We use the Underlying_Type here (and below) in case the
1641 -- type is private without discriminants, but the full type
1642 -- has discriminants. This case is illegal, but we generate it
1643 -- internally for passing to the Extra_Constrained parameter.
1646 -- In Ada 2012, test for case of a limited tagged type, in
1647 -- which case the attribute is always required to return
1648 -- True. The underlying type is tested, to make sure we also
1649 -- return True for cases where there is an unconstrained
1650 -- object with an untagged limited partial view which has
1651 -- defaulted discriminants (such objects always produce a
1652 -- False in earlier versions of Ada). (Ada 2012: AI05-0214)
1654 Res := Is_Constrained (Underlying_Type (Etype (Ent)))
1656 (Ada_Version >= Ada_2012
1657 and then Is_Tagged_Type (Underlying_Type (Ptyp))
1658 and then Is_Limited_Type (Ptyp));
1661 Rewrite (N, New_Reference_To (Boolean_Literals (Res), Loc));
1664 -- Prefix is not an entity name. These are also cases where we can
1665 -- always tell at compile time by looking at the form and type of the
1666 -- prefix. If an explicit dereference of an object with constrained
1667 -- partial view, this is unconstrained (Ada 2005: AI95-0363). If the
1668 -- underlying type is a limited tagged type, then Constrained is
1669 -- required to always return True (Ada 2012: AI05-0214).
1675 not Is_Variable (Pref)
1677 (Nkind (Pref) = N_Explicit_Dereference
1679 not Has_Constrained_Partial_View (Base_Type (Ptyp)))
1680 or else Is_Constrained (Underlying_Type (Ptyp))
1681 or else (Ada_Version >= Ada_2012
1682 and then Is_Tagged_Type (Underlying_Type (Ptyp))
1683 and then Is_Limited_Type (Ptyp))),
1687 Analyze_And_Resolve (N, Standard_Boolean);
1694 -- Transforms 'Copy_Sign into a call to the floating-point attribute
1695 -- function Copy_Sign in Fat_xxx (where xxx is the root type)
1697 when Attribute_Copy_Sign =>
1698 Expand_Fpt_Attribute_RR (N);
1704 -- Transforms 'Count attribute into a call to the Count function
1706 when Attribute_Count => Count : declare
1708 Conctyp : Entity_Id;
1710 Entry_Id : Entity_Id;
1715 -- If the prefix is a member of an entry family, retrieve both
1716 -- entry name and index. For a simple entry there is no index.
1718 if Nkind (Pref) = N_Indexed_Component then
1719 Entnam := Prefix (Pref);
1720 Index := First (Expressions (Pref));
1726 Entry_Id := Entity (Entnam);
1728 -- Find the concurrent type in which this attribute is referenced
1729 -- (there had better be one).
1731 Conctyp := Current_Scope;
1732 while not Is_Concurrent_Type (Conctyp) loop
1733 Conctyp := Scope (Conctyp);
1738 if Is_Protected_Type (Conctyp) then
1739 case Corresponding_Runtime_Package (Conctyp) is
1740 when System_Tasking_Protected_Objects_Entries =>
1741 Name := New_Reference_To (RTE (RE_Protected_Count), Loc);
1744 Make_Function_Call (Loc,
1746 Parameter_Associations => New_List (
1748 (Find_Protection_Object (Current_Scope), Loc),
1749 Entry_Index_Expression
1750 (Loc, Entry_Id, Index, Scope (Entry_Id))));
1752 when System_Tasking_Protected_Objects_Single_Entry =>
1754 New_Reference_To (RTE (RE_Protected_Count_Entry), Loc);
1757 Make_Function_Call (Loc,
1759 Parameter_Associations => New_List (
1761 (Find_Protection_Object (Current_Scope), Loc)));
1764 raise Program_Error;
1771 Make_Function_Call (Loc,
1772 Name => New_Reference_To (RTE (RE_Task_Count), Loc),
1773 Parameter_Associations => New_List (
1774 Entry_Index_Expression (Loc,
1775 Entry_Id, Index, Scope (Entry_Id))));
1778 -- The call returns type Natural but the context is universal integer
1779 -- so any integer type is allowed. The attribute was already resolved
1780 -- so its Etype is the required result type. If the base type of the
1781 -- context type is other than Standard.Integer we put in a conversion
1782 -- to the required type. This can be a normal typed conversion since
1783 -- both input and output types of the conversion are integer types
1785 if Base_Type (Typ) /= Base_Type (Standard_Integer) then
1786 Rewrite (N, Convert_To (Typ, Call));
1791 Analyze_And_Resolve (N, Typ);
1798 -- This processing is shared by Elab_Spec
1800 -- What we do is to insert the following declarations
1803 -- pragma Import (C, enn, "name___elabb/s");
1805 -- and then the Elab_Body/Spec attribute is replaced by a reference
1806 -- to this defining identifier.
1808 when Attribute_Elab_Body |
1809 Attribute_Elab_Spec =>
1811 -- Leave attribute unexpanded in CodePeer mode: the gnat2scil
1812 -- back-end knows how to handle this attribute directly.
1814 if CodePeer_Mode then
1819 Ent : constant Entity_Id := Make_Temporary (Loc, 'E');
1823 procedure Make_Elab_String (Nod : Node_Id);
1824 -- Given Nod, an identifier, or a selected component, put the
1825 -- image into the current string literal, with double underline
1826 -- between components.
1828 ----------------------
1829 -- Make_Elab_String --
1830 ----------------------
1832 procedure Make_Elab_String (Nod : Node_Id) is
1834 if Nkind (Nod) = N_Selected_Component then
1835 Make_Elab_String (Prefix (Nod));
1839 Store_String_Char ('$');
1841 Store_String_Char ('.');
1843 Store_String_Char ('_');
1844 Store_String_Char ('_');
1847 Get_Name_String (Chars (Selector_Name (Nod)));
1850 pragma Assert (Nkind (Nod) = N_Identifier);
1851 Get_Name_String (Chars (Nod));
1854 Store_String_Chars (Name_Buffer (1 .. Name_Len));
1855 end Make_Elab_String;
1857 -- Start of processing for Elab_Body/Elab_Spec
1860 -- First we need to prepare the string literal for the name of
1861 -- the elaboration routine to be referenced.
1864 Make_Elab_String (Pref);
1866 if VM_Target = No_VM then
1867 Store_String_Chars ("___elab");
1868 Lang := Make_Identifier (Loc, Name_C);
1870 Store_String_Chars ("._elab");
1871 Lang := Make_Identifier (Loc, Name_Ada);
1874 if Id = Attribute_Elab_Body then
1875 Store_String_Char ('b');
1877 Store_String_Char ('s');
1882 Insert_Actions (N, New_List (
1883 Make_Subprogram_Declaration (Loc,
1885 Make_Procedure_Specification (Loc,
1886 Defining_Unit_Name => Ent)),
1889 Chars => Name_Import,
1890 Pragma_Argument_Associations => New_List (
1891 Make_Pragma_Argument_Association (Loc, Expression => Lang),
1893 Make_Pragma_Argument_Association (Loc,
1894 Expression => Make_Identifier (Loc, Chars (Ent))),
1896 Make_Pragma_Argument_Association (Loc,
1897 Expression => Make_String_Literal (Loc, Str))))));
1899 Set_Entity (N, Ent);
1900 Rewrite (N, New_Occurrence_Of (Ent, Loc));
1907 -- Elaborated is always True for preelaborated units, predefined units,
1908 -- pure units and units which have Elaborate_Body pragmas. These units
1909 -- have no elaboration entity.
1911 -- Note: The Elaborated attribute is never passed to the back end
1913 when Attribute_Elaborated => Elaborated : declare
1914 Ent : constant Entity_Id := Entity (Pref);
1917 if Present (Elaboration_Entity (Ent)) then
1921 New_Occurrence_Of (Elaboration_Entity (Ent), Loc),
1923 Make_Integer_Literal (Loc, Uint_0)));
1924 Analyze_And_Resolve (N, Typ);
1926 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
1934 when Attribute_Enum_Rep => Enum_Rep :
1936 -- X'Enum_Rep (Y) expands to
1940 -- This is simply a direct conversion from the enumeration type to
1941 -- the target integer type, which is treated by the back end as a
1942 -- normal integer conversion, treating the enumeration type as an
1943 -- integer, which is exactly what we want! We set Conversion_OK to
1944 -- make sure that the analyzer does not complain about what otherwise
1945 -- might be an illegal conversion.
1947 if Is_Non_Empty_List (Exprs) then
1949 OK_Convert_To (Typ, Relocate_Node (First (Exprs))));
1951 -- X'Enum_Rep where X is an enumeration literal is replaced by
1952 -- the literal value.
1954 elsif Ekind (Entity (Pref)) = E_Enumeration_Literal then
1956 Make_Integer_Literal (Loc, Enumeration_Rep (Entity (Pref))));
1958 -- If this is a renaming of a literal, recover the representation
1961 elsif Ekind (Entity (Pref)) = E_Constant
1962 and then Present (Renamed_Object (Entity (Pref)))
1964 Ekind (Entity (Renamed_Object (Entity (Pref))))
1965 = E_Enumeration_Literal
1968 Make_Integer_Literal (Loc,
1969 Enumeration_Rep (Entity (Renamed_Object (Entity (Pref))))));
1971 -- X'Enum_Rep where X is an object does a direct unchecked conversion
1972 -- of the object value, as described for the type case above.
1976 OK_Convert_To (Typ, Relocate_Node (Pref)));
1980 Analyze_And_Resolve (N, Typ);
1987 when Attribute_Enum_Val => Enum_Val : declare
1989 Btyp : constant Entity_Id := Base_Type (Ptyp);
1992 -- X'Enum_Val (Y) expands to
1994 -- [constraint_error when _rep_to_pos (Y, False) = -1, msg]
1997 Expr := Unchecked_Convert_To (Ptyp, First (Exprs));
2000 Make_Raise_Constraint_Error (Loc,
2004 Make_Function_Call (Loc,
2006 New_Reference_To (TSS (Btyp, TSS_Rep_To_Pos), Loc),
2007 Parameter_Associations => New_List (
2008 Relocate_Node (Duplicate_Subexpr (Expr)),
2009 New_Occurrence_Of (Standard_False, Loc))),
2011 Right_Opnd => Make_Integer_Literal (Loc, -1)),
2012 Reason => CE_Range_Check_Failed));
2015 Analyze_And_Resolve (N, Ptyp);
2022 -- Transforms 'Exponent into a call to the floating-point attribute
2023 -- function Exponent in Fat_xxx (where xxx is the root type)
2025 when Attribute_Exponent =>
2026 Expand_Fpt_Attribute_R (N);
2032 -- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag)
2034 when Attribute_External_Tag => External_Tag :
2037 Make_Function_Call (Loc,
2038 Name => New_Reference_To (RTE (RE_External_Tag), Loc),
2039 Parameter_Associations => New_List (
2040 Make_Attribute_Reference (Loc,
2041 Attribute_Name => Name_Tag,
2042 Prefix => Prefix (N)))));
2044 Analyze_And_Resolve (N, Standard_String);
2051 when Attribute_First =>
2053 -- If the prefix type is a constrained packed array type which
2054 -- already has a Packed_Array_Type representation defined, then
2055 -- replace this attribute with a direct reference to 'First of the
2056 -- appropriate index subtype (since otherwise the back end will try
2057 -- to give us the value of 'First for this implementation type).
2059 if Is_Constrained_Packed_Array (Ptyp) then
2061 Make_Attribute_Reference (Loc,
2062 Attribute_Name => Name_First,
2063 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
2064 Analyze_And_Resolve (N, Typ);
2066 elsif Is_Access_Type (Ptyp) then
2067 Apply_Access_Check (N);
2074 -- Compute this if component clause was present, otherwise we leave the
2075 -- computation to be completed in the back-end, since we don't know what
2076 -- layout will be chosen.
2078 when Attribute_First_Bit => First_Bit : declare
2079 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2082 if Known_Static_Component_Bit_Offset (CE) then
2084 Make_Integer_Literal (Loc,
2085 Component_Bit_Offset (CE) mod System_Storage_Unit));
2087 Analyze_And_Resolve (N, Typ);
2090 Apply_Universal_Integer_Attribute_Checks (N);
2100 -- fixtype'Fixed_Value (integer-value)
2104 -- fixtype(integer-value)
2106 -- We do all the required analysis of the conversion here, because we do
2107 -- not want this to go through the fixed-point conversion circuits. Note
2108 -- that the back end always treats fixed-point as equivalent to the
2109 -- corresponding integer type anyway.
2111 when Attribute_Fixed_Value => Fixed_Value :
2114 Make_Type_Conversion (Loc,
2115 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2116 Expression => Relocate_Node (First (Exprs))));
2117 Set_Etype (N, Entity (Pref));
2120 -- Note: it might appear that a properly analyzed unchecked conversion
2121 -- would be just fine here, but that's not the case, since the full
2122 -- range checks performed by the following call are critical!
2124 Apply_Type_Conversion_Checks (N);
2131 -- Transforms 'Floor into a call to the floating-point attribute
2132 -- function Floor in Fat_xxx (where xxx is the root type)
2134 when Attribute_Floor =>
2135 Expand_Fpt_Attribute_R (N);
2141 -- For the fixed-point type Typ:
2147 -- Result_Type (System.Fore (Universal_Real (Type'First)),
2148 -- Universal_Real (Type'Last))
2150 -- Note that we know that the type is a non-static subtype, or Fore
2151 -- would have itself been computed dynamically in Eval_Attribute.
2153 when Attribute_Fore => Fore : begin
2156 Make_Function_Call (Loc,
2157 Name => New_Reference_To (RTE (RE_Fore), Loc),
2159 Parameter_Associations => New_List (
2160 Convert_To (Universal_Real,
2161 Make_Attribute_Reference (Loc,
2162 Prefix => New_Reference_To (Ptyp, Loc),
2163 Attribute_Name => Name_First)),
2165 Convert_To (Universal_Real,
2166 Make_Attribute_Reference (Loc,
2167 Prefix => New_Reference_To (Ptyp, Loc),
2168 Attribute_Name => Name_Last))))));
2170 Analyze_And_Resolve (N, Typ);
2177 -- Transforms 'Fraction into a call to the floating-point attribute
2178 -- function Fraction in Fat_xxx (where xxx is the root type)
2180 when Attribute_Fraction =>
2181 Expand_Fpt_Attribute_R (N);
2187 when Attribute_From_Any => From_Any : declare
2188 P_Type : constant Entity_Id := Etype (Pref);
2189 Decls : constant List_Id := New_List;
2192 Build_From_Any_Call (P_Type,
2193 Relocate_Node (First (Exprs)),
2195 Insert_Actions (N, Decls);
2196 Analyze_And_Resolve (N, P_Type);
2203 -- For an exception returns a reference to the exception data:
2204 -- Exception_Id!(Prefix'Reference)
2206 -- For a task it returns a reference to the _task_id component of
2207 -- corresponding record:
2209 -- taskV!(Prefix)._Task_Id, converted to the type Task_Id defined
2211 -- in Ada.Task_Identification
2213 when Attribute_Identity => Identity : declare
2214 Id_Kind : Entity_Id;
2217 if Ptyp = Standard_Exception_Type then
2218 Id_Kind := RTE (RE_Exception_Id);
2220 if Present (Renamed_Object (Entity (Pref))) then
2221 Set_Entity (Pref, Renamed_Object (Entity (Pref)));
2225 Unchecked_Convert_To (Id_Kind, Make_Reference (Loc, Pref)));
2227 Id_Kind := RTE (RO_AT_Task_Id);
2229 -- If the prefix is a task interface, the Task_Id is obtained
2230 -- dynamically through a dispatching call, as for other task
2231 -- attributes applied to interfaces.
2233 if Ada_Version >= Ada_2005
2234 and then Ekind (Ptyp) = E_Class_Wide_Type
2235 and then Is_Interface (Ptyp)
2236 and then Is_Task_Interface (Ptyp)
2239 Unchecked_Convert_To (Id_Kind,
2240 Make_Selected_Component (Loc,
2242 New_Copy_Tree (Pref),
2244 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))));
2248 Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref)));
2252 Analyze_And_Resolve (N, Id_Kind);
2259 -- Image attribute is handled in separate unit Exp_Imgv
2261 when Attribute_Image =>
2262 Exp_Imgv.Expand_Image_Attribute (N);
2268 -- X'Img is expanded to typ'Image (X), where typ is the type of X
2270 when Attribute_Img => Img :
2273 Make_Attribute_Reference (Loc,
2274 Prefix => New_Reference_To (Ptyp, Loc),
2275 Attribute_Name => Name_Image,
2276 Expressions => New_List (Relocate_Node (Pref))));
2278 Analyze_And_Resolve (N, Standard_String);
2285 when Attribute_Input => Input : declare
2286 P_Type : constant Entity_Id := Entity (Pref);
2287 B_Type : constant Entity_Id := Base_Type (P_Type);
2288 U_Type : constant Entity_Id := Underlying_Type (P_Type);
2289 Strm : constant Node_Id := First (Exprs);
2297 Cntrl : Node_Id := Empty;
2298 -- Value for controlling argument in call. Always Empty except in
2299 -- the dispatching (class-wide type) case, where it is a reference
2300 -- to the dummy object initialized to the right internal tag.
2302 procedure Freeze_Stream_Subprogram (F : Entity_Id);
2303 -- The expansion of the attribute reference may generate a call to
2304 -- a user-defined stream subprogram that is frozen by the call. This
2305 -- can lead to access-before-elaboration problem if the reference
2306 -- appears in an object declaration and the subprogram body has not
2307 -- been seen. The freezing of the subprogram requires special code
2308 -- because it appears in an expanded context where expressions do
2309 -- not freeze their constituents.
2311 ------------------------------
2312 -- Freeze_Stream_Subprogram --
2313 ------------------------------
2315 procedure Freeze_Stream_Subprogram (F : Entity_Id) is
2316 Decl : constant Node_Id := Unit_Declaration_Node (F);
2320 -- If this is user-defined subprogram, the corresponding
2321 -- stream function appears as a renaming-as-body, and the
2322 -- user subprogram must be retrieved by tree traversal.
2325 and then Nkind (Decl) = N_Subprogram_Declaration
2326 and then Present (Corresponding_Body (Decl))
2328 Bod := Corresponding_Body (Decl);
2330 if Nkind (Unit_Declaration_Node (Bod)) =
2331 N_Subprogram_Renaming_Declaration
2333 Set_Is_Frozen (Entity (Name (Unit_Declaration_Node (Bod))));
2336 end Freeze_Stream_Subprogram;
2338 -- Start of processing for Input
2341 -- If no underlying type, we have an error that will be diagnosed
2342 -- elsewhere, so here we just completely ignore the expansion.
2348 -- If there is a TSS for Input, just call it
2350 Fname := Find_Stream_Subprogram (P_Type, TSS_Stream_Input);
2352 if Present (Fname) then
2356 -- If there is a Stream_Convert pragma, use it, we rewrite
2358 -- sourcetyp'Input (stream)
2362 -- sourcetyp (streamread (strmtyp'Input (stream)));
2364 -- where streamread is the given Read function that converts an
2365 -- argument of type strmtyp to type sourcetyp or a type from which
2366 -- it is derived (extra conversion required for the derived case).
2368 Prag := Get_Stream_Convert_Pragma (P_Type);
2370 if Present (Prag) then
2371 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
2372 Rfunc := Entity (Expression (Arg2));
2376 Make_Function_Call (Loc,
2377 Name => New_Occurrence_Of (Rfunc, Loc),
2378 Parameter_Associations => New_List (
2379 Make_Attribute_Reference (Loc,
2382 (Etype (First_Formal (Rfunc)), Loc),
2383 Attribute_Name => Name_Input,
2384 Expressions => Exprs)))));
2386 Analyze_And_Resolve (N, B_Type);
2391 elsif Is_Elementary_Type (U_Type) then
2393 -- A special case arises if we have a defined _Read routine,
2394 -- since in this case we are required to call this routine.
2396 if Present (TSS (Base_Type (U_Type), TSS_Stream_Read)) then
2397 Build_Record_Or_Elementary_Input_Function
2398 (Loc, U_Type, Decl, Fname);
2399 Insert_Action (N, Decl);
2401 -- For normal cases, we call the I_xxx routine directly
2404 Rewrite (N, Build_Elementary_Input_Call (N));
2405 Analyze_And_Resolve (N, P_Type);
2411 elsif Is_Array_Type (U_Type) then
2412 Build_Array_Input_Function (Loc, U_Type, Decl, Fname);
2413 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
2415 -- Dispatching case with class-wide type
2417 elsif Is_Class_Wide_Type (P_Type) then
2419 -- No need to do anything else compiling under restriction
2420 -- No_Dispatching_Calls. During the semantic analysis we
2421 -- already notified such violation.
2423 if Restriction_Active (No_Dispatching_Calls) then
2428 Rtyp : constant Entity_Id := Root_Type (P_Type);
2434 -- Read the internal tag (RM 13.13.2(34)) and use it to
2435 -- initialize a dummy tag object:
2437 -- Dnn : Ada.Tags.Tag :=
2438 -- Descendant_Tag (String'Input (Strm), P_Type);
2440 -- This dummy object is used only to provide a controlling
2441 -- argument for the eventual _Input call. Descendant_Tag is
2442 -- called rather than Internal_Tag to ensure that we have a
2443 -- tag for a type that is descended from the prefix type and
2444 -- declared at the same accessibility level (the exception
2445 -- Tag_Error will be raised otherwise). The level check is
2446 -- required for Ada 2005 because tagged types can be
2447 -- extended in nested scopes (AI-344).
2450 Make_Function_Call (Loc,
2452 New_Occurrence_Of (RTE (RE_Descendant_Tag), Loc),
2453 Parameter_Associations => New_List (
2454 Make_Attribute_Reference (Loc,
2455 Prefix => New_Occurrence_Of (Standard_String, Loc),
2456 Attribute_Name => Name_Input,
2457 Expressions => New_List (
2458 Relocate_Node (Duplicate_Subexpr (Strm)))),
2459 Make_Attribute_Reference (Loc,
2460 Prefix => New_Reference_To (P_Type, Loc),
2461 Attribute_Name => Name_Tag)));
2463 Dnn := Make_Temporary (Loc, 'D', Expr);
2466 Make_Object_Declaration (Loc,
2467 Defining_Identifier => Dnn,
2468 Object_Definition =>
2469 New_Occurrence_Of (RTE (RE_Tag), Loc),
2470 Expression => Expr);
2472 Insert_Action (N, Decl);
2474 -- Now we need to get the entity for the call, and construct
2475 -- a function call node, where we preset a reference to Dnn
2476 -- as the controlling argument (doing an unchecked convert
2477 -- to the class-wide tagged type to make it look like a real
2480 Fname := Find_Prim_Op (Rtyp, TSS_Stream_Input);
2482 Unchecked_Convert_To (P_Type,
2483 New_Occurrence_Of (Dnn, Loc));
2484 Set_Etype (Cntrl, P_Type);
2485 Set_Parent (Cntrl, N);
2488 -- For tagged types, use the primitive Input function
2490 elsif Is_Tagged_Type (U_Type) then
2491 Fname := Find_Prim_Op (U_Type, TSS_Stream_Input);
2493 -- All other record type cases, including protected records. The
2494 -- latter only arise for expander generated code for handling
2495 -- shared passive partition access.
2499 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
2501 -- Ada 2005 (AI-216): Program_Error is raised executing default
2502 -- implementation of the Input attribute of an unchecked union
2503 -- type if the type lacks default discriminant values.
2505 if Is_Unchecked_Union (Base_Type (U_Type))
2506 and then No (Discriminant_Constraint (U_Type))
2509 Make_Raise_Program_Error (Loc,
2510 Reason => PE_Unchecked_Union_Restriction));
2515 Build_Record_Or_Elementary_Input_Function
2516 (Loc, Base_Type (U_Type), Decl, Fname);
2517 Insert_Action (N, Decl);
2519 if Nkind (Parent (N)) = N_Object_Declaration
2520 and then Is_Record_Type (U_Type)
2522 -- The stream function may contain calls to user-defined
2523 -- Read procedures for individual components.
2530 Comp := First_Component (U_Type);
2531 while Present (Comp) loop
2533 Find_Stream_Subprogram
2534 (Etype (Comp), TSS_Stream_Read);
2536 if Present (Func) then
2537 Freeze_Stream_Subprogram (Func);
2540 Next_Component (Comp);
2547 -- If we fall through, Fname is the function to be called. The result
2548 -- is obtained by calling the appropriate function, then converting
2549 -- the result. The conversion does a subtype check.
2552 Make_Function_Call (Loc,
2553 Name => New_Occurrence_Of (Fname, Loc),
2554 Parameter_Associations => New_List (
2555 Relocate_Node (Strm)));
2557 Set_Controlling_Argument (Call, Cntrl);
2558 Rewrite (N, Unchecked_Convert_To (P_Type, Call));
2559 Analyze_And_Resolve (N, P_Type);
2561 if Nkind (Parent (N)) = N_Object_Declaration then
2562 Freeze_Stream_Subprogram (Fname);
2572 -- inttype'Fixed_Value (fixed-value)
2576 -- inttype(integer-value))
2578 -- we do all the required analysis of the conversion here, because we do
2579 -- not want this to go through the fixed-point conversion circuits. Note
2580 -- that the back end always treats fixed-point as equivalent to the
2581 -- corresponding integer type anyway.
2583 when Attribute_Integer_Value => Integer_Value :
2586 Make_Type_Conversion (Loc,
2587 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2588 Expression => Relocate_Node (First (Exprs))));
2589 Set_Etype (N, Entity (Pref));
2592 -- Note: it might appear that a properly analyzed unchecked conversion
2593 -- would be just fine here, but that's not the case, since the full
2594 -- range checks performed by the following call are critical!
2596 Apply_Type_Conversion_Checks (N);
2603 when Attribute_Invalid_Value =>
2604 Rewrite (N, Get_Simple_Init_Val (Ptyp, N));
2610 when Attribute_Last =>
2612 -- If the prefix type is a constrained packed array type which
2613 -- already has a Packed_Array_Type representation defined, then
2614 -- replace this attribute with a direct reference to 'Last of the
2615 -- appropriate index subtype (since otherwise the back end will try
2616 -- to give us the value of 'Last for this implementation type).
2618 if Is_Constrained_Packed_Array (Ptyp) then
2620 Make_Attribute_Reference (Loc,
2621 Attribute_Name => Name_Last,
2622 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
2623 Analyze_And_Resolve (N, Typ);
2625 elsif Is_Access_Type (Ptyp) then
2626 Apply_Access_Check (N);
2633 -- We compute this if a component clause was present, otherwise we leave
2634 -- the computation up to the back end, since we don't know what layout
2637 when Attribute_Last_Bit => Last_Bit : declare
2638 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2641 if Known_Static_Component_Bit_Offset (CE)
2642 and then Known_Static_Esize (CE)
2645 Make_Integer_Literal (Loc,
2646 Intval => (Component_Bit_Offset (CE) mod System_Storage_Unit)
2649 Analyze_And_Resolve (N, Typ);
2652 Apply_Universal_Integer_Attribute_Checks (N);
2660 -- Transforms 'Leading_Part into a call to the floating-point attribute
2661 -- function Leading_Part in Fat_xxx (where xxx is the root type)
2663 -- Note: strictly, we should generate special case code to deal with
2664 -- absurdly large positive arguments (greater than Integer'Last), which
2665 -- result in returning the first argument unchanged, but it hardly seems
2666 -- worth the effort. We raise constraint error for absurdly negative
2667 -- arguments which is fine.
2669 when Attribute_Leading_Part =>
2670 Expand_Fpt_Attribute_RI (N);
2676 when Attribute_Length => declare
2681 -- Processing for packed array types
2683 if Is_Array_Type (Ptyp) and then Is_Packed (Ptyp) then
2684 Ityp := Get_Index_Subtype (N);
2686 -- If the index type, Ityp, is an enumeration type with holes,
2687 -- then we calculate X'Length explicitly using
2690 -- (0, Ityp'Pos (X'Last (N)) -
2691 -- Ityp'Pos (X'First (N)) + 1);
2693 -- Since the bounds in the template are the representation values
2694 -- and the back end would get the wrong value.
2696 if Is_Enumeration_Type (Ityp)
2697 and then Present (Enum_Pos_To_Rep (Base_Type (Ityp)))
2702 Xnum := Expr_Value (First (Expressions (N)));
2706 Make_Attribute_Reference (Loc,
2707 Prefix => New_Occurrence_Of (Typ, Loc),
2708 Attribute_Name => Name_Max,
2709 Expressions => New_List
2710 (Make_Integer_Literal (Loc, 0),
2714 Make_Op_Subtract (Loc,
2716 Make_Attribute_Reference (Loc,
2717 Prefix => New_Occurrence_Of (Ityp, Loc),
2718 Attribute_Name => Name_Pos,
2720 Expressions => New_List (
2721 Make_Attribute_Reference (Loc,
2722 Prefix => Duplicate_Subexpr (Pref),
2723 Attribute_Name => Name_Last,
2724 Expressions => New_List (
2725 Make_Integer_Literal (Loc, Xnum))))),
2728 Make_Attribute_Reference (Loc,
2729 Prefix => New_Occurrence_Of (Ityp, Loc),
2730 Attribute_Name => Name_Pos,
2732 Expressions => New_List (
2733 Make_Attribute_Reference (Loc,
2735 Duplicate_Subexpr_No_Checks (Pref),
2736 Attribute_Name => Name_First,
2737 Expressions => New_List (
2738 Make_Integer_Literal (Loc, Xnum)))))),
2740 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
2742 Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
2745 -- If the prefix type is a constrained packed array type which
2746 -- already has a Packed_Array_Type representation defined, then
2747 -- replace this attribute with a direct reference to 'Range_Length
2748 -- of the appropriate index subtype (since otherwise the back end
2749 -- will try to give us the value of 'Length for this
2750 -- implementation type).
2752 elsif Is_Constrained (Ptyp) then
2754 Make_Attribute_Reference (Loc,
2755 Attribute_Name => Name_Range_Length,
2756 Prefix => New_Reference_To (Ityp, Loc)));
2757 Analyze_And_Resolve (N, Typ);
2762 elsif Is_Access_Type (Ptyp) then
2763 Apply_Access_Check (N);
2765 -- If the designated type is a packed array type, then we convert
2766 -- the reference to:
2769 -- xtyp'Pos (Pref'Last (Expr)) -
2770 -- xtyp'Pos (Pref'First (Expr)));
2772 -- This is a bit complex, but it is the easiest thing to do that
2773 -- works in all cases including enum types with holes xtyp here
2774 -- is the appropriate index type.
2777 Dtyp : constant Entity_Id := Designated_Type (Ptyp);
2781 if Is_Array_Type (Dtyp) and then Is_Packed (Dtyp) then
2782 Xtyp := Get_Index_Subtype (N);
2785 Make_Attribute_Reference (Loc,
2786 Prefix => New_Occurrence_Of (Typ, Loc),
2787 Attribute_Name => Name_Max,
2788 Expressions => New_List (
2789 Make_Integer_Literal (Loc, 0),
2792 Make_Integer_Literal (Loc, 1),
2793 Make_Op_Subtract (Loc,
2795 Make_Attribute_Reference (Loc,
2796 Prefix => New_Occurrence_Of (Xtyp, Loc),
2797 Attribute_Name => Name_Pos,
2798 Expressions => New_List (
2799 Make_Attribute_Reference (Loc,
2800 Prefix => Duplicate_Subexpr (Pref),
2801 Attribute_Name => Name_Last,
2803 New_Copy_List (Exprs)))),
2806 Make_Attribute_Reference (Loc,
2807 Prefix => New_Occurrence_Of (Xtyp, Loc),
2808 Attribute_Name => Name_Pos,
2809 Expressions => New_List (
2810 Make_Attribute_Reference (Loc,
2812 Duplicate_Subexpr_No_Checks (Pref),
2813 Attribute_Name => Name_First,
2815 New_Copy_List (Exprs)))))))));
2817 Analyze_And_Resolve (N, Typ);
2821 -- Otherwise leave it to the back end
2824 Apply_Universal_Integer_Attribute_Checks (N);
2832 -- Transforms 'Machine into a call to the floating-point attribute
2833 -- function Machine in Fat_xxx (where xxx is the root type)
2835 when Attribute_Machine =>
2836 Expand_Fpt_Attribute_R (N);
2838 ----------------------
2839 -- Machine_Rounding --
2840 ----------------------
2842 -- Transforms 'Machine_Rounding into a call to the floating-point
2843 -- attribute function Machine_Rounding in Fat_xxx (where xxx is the root
2844 -- type). Expansion is avoided for cases the back end can handle
2847 when Attribute_Machine_Rounding =>
2848 if not Is_Inline_Floating_Point_Attribute (N) then
2849 Expand_Fpt_Attribute_R (N);
2856 -- Machine_Size is equivalent to Object_Size, so transform it into
2857 -- Object_Size and that way the back end never sees Machine_Size.
2859 when Attribute_Machine_Size =>
2861 Make_Attribute_Reference (Loc,
2862 Prefix => Prefix (N),
2863 Attribute_Name => Name_Object_Size));
2865 Analyze_And_Resolve (N, Typ);
2871 -- The only case that can get this far is the dynamic case of the old
2872 -- Ada 83 Mantissa attribute for the fixed-point case. For this case,
2879 -- ityp (System.Mantissa.Mantissa_Value
2880 -- (Integer'Integer_Value (typ'First),
2881 -- Integer'Integer_Value (typ'Last)));
2883 when Attribute_Mantissa => Mantissa : begin
2886 Make_Function_Call (Loc,
2887 Name => New_Occurrence_Of (RTE (RE_Mantissa_Value), Loc),
2889 Parameter_Associations => New_List (
2891 Make_Attribute_Reference (Loc,
2892 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2893 Attribute_Name => Name_Integer_Value,
2894 Expressions => New_List (
2896 Make_Attribute_Reference (Loc,
2897 Prefix => New_Occurrence_Of (Ptyp, Loc),
2898 Attribute_Name => Name_First))),
2900 Make_Attribute_Reference (Loc,
2901 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2902 Attribute_Name => Name_Integer_Value,
2903 Expressions => New_List (
2905 Make_Attribute_Reference (Loc,
2906 Prefix => New_Occurrence_Of (Ptyp, Loc),
2907 Attribute_Name => Name_Last)))))));
2909 Analyze_And_Resolve (N, Typ);
2912 --------------------
2913 -- Mechanism_Code --
2914 --------------------
2916 when Attribute_Mechanism_Code =>
2918 -- We must replace the prefix in the renamed case
2920 if Is_Entity_Name (Pref)
2921 and then Present (Alias (Entity (Pref)))
2923 Set_Renamed_Subprogram (Pref, Alias (Entity (Pref)));
2930 when Attribute_Mod => Mod_Case : declare
2931 Arg : constant Node_Id := Relocate_Node (First (Exprs));
2932 Hi : constant Node_Id := Type_High_Bound (Etype (Arg));
2933 Modv : constant Uint := Modulus (Btyp);
2937 -- This is not so simple. The issue is what type to use for the
2938 -- computation of the modular value.
2940 -- The easy case is when the modulus value is within the bounds
2941 -- of the signed integer type of the argument. In this case we can
2942 -- just do the computation in that signed integer type, and then
2943 -- do an ordinary conversion to the target type.
2945 if Modv <= Expr_Value (Hi) then
2950 Right_Opnd => Make_Integer_Literal (Loc, Modv))));
2952 -- Here we know that the modulus is larger than type'Last of the
2953 -- integer type. There are two cases to consider:
2955 -- a) The integer value is non-negative. In this case, it is
2956 -- returned as the result (since it is less than the modulus).
2958 -- b) The integer value is negative. In this case, we know that the
2959 -- result is modulus + value, where the value might be as small as
2960 -- -modulus. The trouble is what type do we use to do the subtract.
2961 -- No type will do, since modulus can be as big as 2**64, and no
2962 -- integer type accommodates this value. Let's do bit of algebra
2965 -- = modulus - (-value)
2966 -- = (modulus - 1) - (-value - 1)
2968 -- Now modulus - 1 is certainly in range of the modular type.
2969 -- -value is in the range 1 .. modulus, so -value -1 is in the
2970 -- range 0 .. modulus-1 which is in range of the modular type.
2971 -- Furthermore, (-value - 1) can be expressed as -(value + 1)
2972 -- which we can compute using the integer base type.
2974 -- Once this is done we analyze the conditional expression without
2975 -- range checks, because we know everything is in range, and we
2976 -- want to prevent spurious warnings on either branch.
2980 Make_Conditional_Expression (Loc,
2981 Expressions => New_List (
2983 Left_Opnd => Duplicate_Subexpr (Arg),
2984 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2987 Duplicate_Subexpr_No_Checks (Arg)),
2989 Make_Op_Subtract (Loc,
2991 Make_Integer_Literal (Loc,
2992 Intval => Modv - 1),
2998 Left_Opnd => Duplicate_Subexpr_No_Checks (Arg),
3000 Make_Integer_Literal (Loc,
3001 Intval => 1))))))));
3005 Analyze_And_Resolve (N, Btyp, Suppress => All_Checks);
3012 -- Transforms 'Model into a call to the floating-point attribute
3013 -- function Model in Fat_xxx (where xxx is the root type)
3015 when Attribute_Model =>
3016 Expand_Fpt_Attribute_R (N);
3022 -- The processing for Object_Size shares the processing for Size
3028 when Attribute_Old => Old : declare
3029 Tnn : constant Entity_Id := Make_Temporary (Loc, 'T', Pref);
3034 -- Find the nearest subprogram body, ignoring _Preconditions
3038 Subp := Parent (Subp);
3039 exit when Nkind (Subp) = N_Subprogram_Body
3040 and then Chars (Defining_Entity (Subp)) /= Name_uPostconditions;
3043 -- Insert the initialized object declaration at the start of the
3044 -- subprogram's declarations.
3047 Make_Object_Declaration (Loc,
3048 Defining_Identifier => Tnn,
3049 Constant_Present => True,
3050 Object_Definition => New_Occurrence_Of (Etype (N), Loc),
3051 Expression => Pref);
3053 -- Push the subprogram's scope, so that the object will be analyzed
3054 -- in that context (rather than the context of the Precondition
3055 -- subprogram) and will have its Scope set properly.
3057 if Present (Corresponding_Spec (Subp)) then
3058 Push_Scope (Corresponding_Spec (Subp));
3060 Push_Scope (Defining_Entity (Subp));
3063 if Is_Empty_List (Declarations (Subp)) then
3064 Set_Declarations (Subp, New_List (Asn_Stm));
3067 Insert_Action (First (Declarations (Subp)), Asn_Stm);
3072 Rewrite (N, New_Occurrence_Of (Tnn, Loc));
3079 when Attribute_Output => Output : declare
3080 P_Type : constant Entity_Id := Entity (Pref);
3081 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3089 -- If no underlying type, we have an error that will be diagnosed
3090 -- elsewhere, so here we just completely ignore the expansion.
3096 -- If TSS for Output is present, just call it
3098 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Output);
3100 if Present (Pname) then
3104 -- If there is a Stream_Convert pragma, use it, we rewrite
3106 -- sourcetyp'Output (stream, Item)
3110 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
3112 -- where strmwrite is the given Write function that converts an
3113 -- argument of type sourcetyp or a type acctyp, from which it is
3114 -- derived to type strmtyp. The conversion to acttyp is required
3115 -- for the derived case.
3117 Prag := Get_Stream_Convert_Pragma (P_Type);
3119 if Present (Prag) then
3121 Next (Next (First (Pragma_Argument_Associations (Prag))));
3122 Wfunc := Entity (Expression (Arg3));
3125 Make_Attribute_Reference (Loc,
3126 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
3127 Attribute_Name => Name_Output,
3128 Expressions => New_List (
3129 Relocate_Node (First (Exprs)),
3130 Make_Function_Call (Loc,
3131 Name => New_Occurrence_Of (Wfunc, Loc),
3132 Parameter_Associations => New_List (
3133 OK_Convert_To (Etype (First_Formal (Wfunc)),
3134 Relocate_Node (Next (First (Exprs)))))))));
3139 -- For elementary types, we call the W_xxx routine directly.
3140 -- Note that the effect of Write and Output is identical for
3141 -- the case of an elementary type, since there are no
3142 -- discriminants or bounds.
3144 elsif Is_Elementary_Type (U_Type) then
3146 -- A special case arises if we have a defined _Write routine,
3147 -- since in this case we are required to call this routine.
3149 if Present (TSS (Base_Type (U_Type), TSS_Stream_Write)) then
3150 Build_Record_Or_Elementary_Output_Procedure
3151 (Loc, U_Type, Decl, Pname);
3152 Insert_Action (N, Decl);
3154 -- For normal cases, we call the W_xxx routine directly
3157 Rewrite (N, Build_Elementary_Write_Call (N));
3164 elsif Is_Array_Type (U_Type) then
3165 Build_Array_Output_Procedure (Loc, U_Type, Decl, Pname);
3166 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3168 -- Class-wide case, first output external tag, then dispatch
3169 -- to the appropriate primitive Output function (RM 13.13.2(31)).
3171 elsif Is_Class_Wide_Type (P_Type) then
3173 -- No need to do anything else compiling under restriction
3174 -- No_Dispatching_Calls. During the semantic analysis we
3175 -- already notified such violation.
3177 if Restriction_Active (No_Dispatching_Calls) then
3182 Strm : constant Node_Id := First (Exprs);
3183 Item : constant Node_Id := Next (Strm);
3186 -- Ada 2005 (AI-344): Check that the accessibility level
3187 -- of the type of the output object is not deeper than
3188 -- that of the attribute's prefix type.
3190 -- if Get_Access_Level (Item'Tag)
3191 -- /= Get_Access_Level (P_Type'Tag)
3196 -- String'Output (Strm, External_Tag (Item'Tag));
3198 -- We cannot figure out a practical way to implement this
3199 -- accessibility check on virtual machines, so we omit it.
3201 if Ada_Version >= Ada_2005
3202 and then Tagged_Type_Expansion
3205 Make_Implicit_If_Statement (N,
3209 Build_Get_Access_Level (Loc,
3210 Make_Attribute_Reference (Loc,
3213 Duplicate_Subexpr (Item,
3215 Attribute_Name => Name_Tag)),
3218 Make_Integer_Literal (Loc,
3219 Type_Access_Level (P_Type))),
3222 New_List (Make_Raise_Statement (Loc,
3224 RTE (RE_Tag_Error), Loc)))));
3228 Make_Attribute_Reference (Loc,
3229 Prefix => New_Occurrence_Of (Standard_String, Loc),
3230 Attribute_Name => Name_Output,
3231 Expressions => New_List (
3232 Relocate_Node (Duplicate_Subexpr (Strm)),
3233 Make_Function_Call (Loc,
3235 New_Occurrence_Of (RTE (RE_External_Tag), Loc),
3236 Parameter_Associations => New_List (
3237 Make_Attribute_Reference (Loc,
3240 (Duplicate_Subexpr (Item, Name_Req => True)),
3241 Attribute_Name => Name_Tag))))));
3244 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
3246 -- Tagged type case, use the primitive Output function
3248 elsif Is_Tagged_Type (U_Type) then
3249 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
3251 -- All other record type cases, including protected records.
3252 -- The latter only arise for expander generated code for
3253 -- handling shared passive partition access.
3257 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3259 -- Ada 2005 (AI-216): Program_Error is raised when executing
3260 -- the default implementation of the Output attribute of an
3261 -- unchecked union type if the type lacks default discriminant
3264 if Is_Unchecked_Union (Base_Type (U_Type))
3265 and then No (Discriminant_Constraint (U_Type))
3268 Make_Raise_Program_Error (Loc,
3269 Reason => PE_Unchecked_Union_Restriction));
3274 Build_Record_Or_Elementary_Output_Procedure
3275 (Loc, Base_Type (U_Type), Decl, Pname);
3276 Insert_Action (N, Decl);
3280 -- If we fall through, Pname is the name of the procedure to call
3282 Rewrite_Stream_Proc_Call (Pname);
3289 -- For enumeration types with a standard representation, Pos is
3290 -- handled by the back end.
3292 -- For enumeration types, with a non-standard representation we generate
3293 -- a call to the _Rep_To_Pos function created when the type was frozen.
3294 -- The call has the form
3296 -- _rep_to_pos (expr, flag)
3298 -- The parameter flag is True if range checks are enabled, causing
3299 -- Program_Error to be raised if the expression has an invalid
3300 -- representation, and False if range checks are suppressed.
3302 -- For integer types, Pos is equivalent to a simple integer
3303 -- conversion and we rewrite it as such
3305 when Attribute_Pos => Pos :
3307 Etyp : Entity_Id := Base_Type (Entity (Pref));
3310 -- Deal with zero/non-zero boolean values
3312 if Is_Boolean_Type (Etyp) then
3313 Adjust_Condition (First (Exprs));
3314 Etyp := Standard_Boolean;
3315 Set_Prefix (N, New_Occurrence_Of (Standard_Boolean, Loc));
3318 -- Case of enumeration type
3320 if Is_Enumeration_Type (Etyp) then
3322 -- Non-standard enumeration type (generate call)
3324 if Present (Enum_Pos_To_Rep (Etyp)) then
3325 Append_To (Exprs, Rep_To_Pos_Flag (Etyp, Loc));
3328 Make_Function_Call (Loc,
3330 New_Reference_To (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3331 Parameter_Associations => Exprs)));
3333 Analyze_And_Resolve (N, Typ);
3335 -- Standard enumeration type (do universal integer check)
3338 Apply_Universal_Integer_Attribute_Checks (N);
3341 -- Deal with integer types (replace by conversion)
3343 elsif Is_Integer_Type (Etyp) then
3344 Rewrite (N, Convert_To (Typ, First (Exprs)));
3345 Analyze_And_Resolve (N, Typ);
3354 -- We compute this if a component clause was present, otherwise we leave
3355 -- the computation up to the back end, since we don't know what layout
3358 when Attribute_Position => Position :
3360 CE : constant Entity_Id := Entity (Selector_Name (Pref));
3363 if Present (Component_Clause (CE)) then
3365 Make_Integer_Literal (Loc,
3366 Intval => Component_Bit_Offset (CE) / System_Storage_Unit));
3367 Analyze_And_Resolve (N, Typ);
3370 Apply_Universal_Integer_Attribute_Checks (N);
3378 -- 1. Deal with enumeration types with holes
3379 -- 2. For floating-point, generate call to attribute function
3380 -- 3. For other cases, deal with constraint checking
3382 when Attribute_Pred => Pred :
3384 Etyp : constant Entity_Id := Base_Type (Ptyp);
3388 -- For enumeration types with non-standard representations, we
3389 -- expand typ'Pred (x) into
3391 -- Pos_To_Rep (Rep_To_Pos (x) - 1)
3393 -- If the representation is contiguous, we compute instead
3394 -- Lit1 + Rep_to_Pos (x -1), to catch invalid representations.
3395 -- The conversion function Enum_Pos_To_Rep is defined on the
3396 -- base type, not the subtype, so we have to use the base type
3397 -- explicitly for this and other enumeration attributes.
3399 if Is_Enumeration_Type (Ptyp)
3400 and then Present (Enum_Pos_To_Rep (Etyp))
3402 if Has_Contiguous_Rep (Etyp) then
3404 Unchecked_Convert_To (Ptyp,
3407 Make_Integer_Literal (Loc,
3408 Enumeration_Rep (First_Literal (Ptyp))),
3410 Make_Function_Call (Loc,
3413 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3415 Parameter_Associations =>
3417 Unchecked_Convert_To (Ptyp,
3418 Make_Op_Subtract (Loc,
3420 Unchecked_Convert_To (Standard_Integer,
3421 Relocate_Node (First (Exprs))),
3423 Make_Integer_Literal (Loc, 1))),
3424 Rep_To_Pos_Flag (Ptyp, Loc))))));
3427 -- Add Boolean parameter True, to request program errror if
3428 -- we have a bad representation on our hands. If checks are
3429 -- suppressed, then add False instead
3431 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
3433 Make_Indexed_Component (Loc,
3436 (Enum_Pos_To_Rep (Etyp), Loc),
3437 Expressions => New_List (
3438 Make_Op_Subtract (Loc,
3440 Make_Function_Call (Loc,
3443 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3444 Parameter_Associations => Exprs),
3445 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
3448 Analyze_And_Resolve (N, Typ);
3450 -- For floating-point, we transform 'Pred into a call to the Pred
3451 -- floating-point attribute function in Fat_xxx (xxx is root type)
3453 elsif Is_Floating_Point_Type (Ptyp) then
3454 Expand_Fpt_Attribute_R (N);
3455 Analyze_And_Resolve (N, Typ);
3457 -- For modular types, nothing to do (no overflow, since wraps)
3459 elsif Is_Modular_Integer_Type (Ptyp) then
3462 -- For other types, if argument is marked as needing a range check or
3463 -- overflow checking is enabled, we must generate a check.
3465 elsif not Overflow_Checks_Suppressed (Ptyp)
3466 or else Do_Range_Check (First (Exprs))
3468 Set_Do_Range_Check (First (Exprs), False);
3469 Expand_Pred_Succ (N);
3477 -- Ada 2005 (AI-327): Dynamic ceiling priorities
3479 -- We rewrite X'Priority as the following run-time call:
3481 -- Get_Ceiling (X._Object)
3483 -- Note that although X'Priority is notionally an object, it is quite
3484 -- deliberately not defined as an aliased object in the RM. This means
3485 -- that it works fine to rewrite it as a call, without having to worry
3486 -- about complications that would other arise from X'Priority'Access,
3487 -- which is illegal, because of the lack of aliasing.
3489 when Attribute_Priority =>
3492 Conctyp : Entity_Id;
3493 Object_Parm : Node_Id;
3495 RT_Subprg_Name : Node_Id;
3498 -- Look for the enclosing concurrent type
3500 Conctyp := Current_Scope;
3501 while not Is_Concurrent_Type (Conctyp) loop
3502 Conctyp := Scope (Conctyp);
3505 pragma Assert (Is_Protected_Type (Conctyp));
3507 -- Generate the actual of the call
3509 Subprg := Current_Scope;
3510 while not Present (Protected_Body_Subprogram (Subprg)) loop
3511 Subprg := Scope (Subprg);
3514 -- Use of 'Priority inside protected entries and barriers (in
3515 -- both cases the type of the first formal of their expanded
3516 -- subprogram is Address)
3518 if Etype (First_Entity (Protected_Body_Subprogram (Subprg)))
3522 New_Itype : Entity_Id;
3525 -- In the expansion of protected entries the type of the
3526 -- first formal of the Protected_Body_Subprogram is an
3527 -- Address. In order to reference the _object component
3530 -- type T is access p__ptTV;
3533 New_Itype := Create_Itype (E_Access_Type, N);
3534 Set_Etype (New_Itype, New_Itype);
3535 Set_Directly_Designated_Type (New_Itype,
3536 Corresponding_Record_Type (Conctyp));
3537 Freeze_Itype (New_Itype, N);
3540 -- T!(O)._object'unchecked_access
3543 Make_Attribute_Reference (Loc,
3545 Make_Selected_Component (Loc,
3547 Unchecked_Convert_To (New_Itype,
3550 (Protected_Body_Subprogram (Subprg)),
3553 Make_Identifier (Loc, Name_uObject)),
3554 Attribute_Name => Name_Unchecked_Access);
3557 -- Use of 'Priority inside a protected subprogram
3561 Make_Attribute_Reference (Loc,
3563 Make_Selected_Component (Loc,
3564 Prefix => New_Reference_To
3566 (Protected_Body_Subprogram (Subprg)),
3568 Selector_Name => Make_Identifier (Loc, Name_uObject)),
3569 Attribute_Name => Name_Unchecked_Access);
3572 -- Select the appropriate run-time subprogram
3574 if Number_Entries (Conctyp) = 0 then
3576 New_Reference_To (RTE (RE_Get_Ceiling), Loc);
3579 New_Reference_To (RTE (RO_PE_Get_Ceiling), Loc);
3583 Make_Function_Call (Loc,
3584 Name => RT_Subprg_Name,
3585 Parameter_Associations => New_List (Object_Parm));
3589 -- Avoid the generation of extra checks on the pointer to the
3590 -- protected object.
3592 Analyze_And_Resolve (N, Typ, Suppress => Access_Check);
3599 when Attribute_Range_Length => Range_Length : begin
3601 -- The only special processing required is for the case where
3602 -- Range_Length is applied to an enumeration type with holes.
3603 -- In this case we transform
3609 -- X'Pos (X'Last) - X'Pos (X'First) + 1
3611 -- So that the result reflects the proper Pos values instead
3612 -- of the underlying representations.
3614 if Is_Enumeration_Type (Ptyp)
3615 and then Has_Non_Standard_Rep (Ptyp)
3620 Make_Op_Subtract (Loc,
3622 Make_Attribute_Reference (Loc,
3623 Attribute_Name => Name_Pos,
3624 Prefix => New_Occurrence_Of (Ptyp, Loc),
3625 Expressions => New_List (
3626 Make_Attribute_Reference (Loc,
3627 Attribute_Name => Name_Last,
3628 Prefix => New_Occurrence_Of (Ptyp, Loc)))),
3631 Make_Attribute_Reference (Loc,
3632 Attribute_Name => Name_Pos,
3633 Prefix => New_Occurrence_Of (Ptyp, Loc),
3634 Expressions => New_List (
3635 Make_Attribute_Reference (Loc,
3636 Attribute_Name => Name_First,
3637 Prefix => New_Occurrence_Of (Ptyp, Loc))))),
3639 Right_Opnd => Make_Integer_Literal (Loc, 1)));
3641 Analyze_And_Resolve (N, Typ);
3643 -- For all other cases, the attribute is handled by the back end, but
3644 -- we need to deal with the case of the range check on a universal
3648 Apply_Universal_Integer_Attribute_Checks (N);
3656 when Attribute_Read => Read : declare
3657 P_Type : constant Entity_Id := Entity (Pref);
3658 B_Type : constant Entity_Id := Base_Type (P_Type);
3659 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3669 -- If no underlying type, we have an error that will be diagnosed
3670 -- elsewhere, so here we just completely ignore the expansion.
3676 -- The simple case, if there is a TSS for Read, just call it
3678 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Read);
3680 if Present (Pname) then
3684 -- If there is a Stream_Convert pragma, use it, we rewrite
3686 -- sourcetyp'Read (stream, Item)
3690 -- Item := sourcetyp (strmread (strmtyp'Input (Stream)));
3692 -- where strmread is the given Read function that converts an
3693 -- argument of type strmtyp to type sourcetyp or a type from which
3694 -- it is derived. The conversion to sourcetyp is required in the
3697 -- A special case arises if Item is a type conversion in which
3698 -- case, we have to expand to:
3700 -- Itemx := typex (strmread (strmtyp'Input (Stream)));
3702 -- where Itemx is the expression of the type conversion (i.e.
3703 -- the actual object), and typex is the type of Itemx.
3705 Prag := Get_Stream_Convert_Pragma (P_Type);
3707 if Present (Prag) then
3708 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
3709 Rfunc := Entity (Expression (Arg2));
3710 Lhs := Relocate_Node (Next (First (Exprs)));
3712 OK_Convert_To (B_Type,
3713 Make_Function_Call (Loc,
3714 Name => New_Occurrence_Of (Rfunc, Loc),
3715 Parameter_Associations => New_List (
3716 Make_Attribute_Reference (Loc,
3719 (Etype (First_Formal (Rfunc)), Loc),
3720 Attribute_Name => Name_Input,
3721 Expressions => New_List (
3722 Relocate_Node (First (Exprs)))))));
3724 if Nkind (Lhs) = N_Type_Conversion then
3725 Lhs := Expression (Lhs);
3726 Rhs := Convert_To (Etype (Lhs), Rhs);
3730 Make_Assignment_Statement (Loc,
3732 Expression => Rhs));
3733 Set_Assignment_OK (Lhs);
3737 -- For elementary types, we call the I_xxx routine using the first
3738 -- parameter and then assign the result into the second parameter.
3739 -- We set Assignment_OK to deal with the conversion case.
3741 elsif Is_Elementary_Type (U_Type) then
3747 Lhs := Relocate_Node (Next (First (Exprs)));
3748 Rhs := Build_Elementary_Input_Call (N);
3750 if Nkind (Lhs) = N_Type_Conversion then
3751 Lhs := Expression (Lhs);
3752 Rhs := Convert_To (Etype (Lhs), Rhs);
3755 Set_Assignment_OK (Lhs);
3758 Make_Assignment_Statement (Loc,
3760 Expression => Rhs));
3768 elsif Is_Array_Type (U_Type) then
3769 Build_Array_Read_Procedure (N, U_Type, Decl, Pname);
3770 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3772 -- Tagged type case, use the primitive Read function. Note that
3773 -- this will dispatch in the class-wide case which is what we want
3775 elsif Is_Tagged_Type (U_Type) then
3776 Pname := Find_Prim_Op (U_Type, TSS_Stream_Read);
3778 -- All other record type cases, including protected records. The
3779 -- latter only arise for expander generated code for handling
3780 -- shared passive partition access.
3784 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3786 -- Ada 2005 (AI-216): Program_Error is raised when executing
3787 -- the default implementation of the Read attribute of an
3788 -- Unchecked_Union type.
3790 if Is_Unchecked_Union (Base_Type (U_Type)) then
3792 Make_Raise_Program_Error (Loc,
3793 Reason => PE_Unchecked_Union_Restriction));
3796 if Has_Discriminants (U_Type)
3798 (Discriminant_Default_Value (First_Discriminant (U_Type)))
3800 Build_Mutable_Record_Read_Procedure
3801 (Loc, Full_Base (U_Type), Decl, Pname);
3803 Build_Record_Read_Procedure
3804 (Loc, Full_Base (U_Type), Decl, Pname);
3807 -- Suppress checks, uninitialized or otherwise invalid
3808 -- data does not cause constraint errors to be raised for
3809 -- a complete record read.
3811 Insert_Action (N, Decl, All_Checks);
3815 Rewrite_Stream_Proc_Call (Pname);
3822 -- Ref is identical to To_Address, see To_Address for processing
3828 -- Transforms 'Remainder into a call to the floating-point attribute
3829 -- function Remainder in Fat_xxx (where xxx is the root type)
3831 when Attribute_Remainder =>
3832 Expand_Fpt_Attribute_RR (N);
3838 -- Transform 'Result into reference to _Result formal. At the point
3839 -- where a legal 'Result attribute is expanded, we know that we are in
3840 -- the context of a _Postcondition function with a _Result parameter.
3842 when Attribute_Result =>
3843 Rewrite (N, Make_Identifier (Loc, Chars => Name_uResult));
3844 Analyze_And_Resolve (N, Typ);
3850 -- The handling of the Round attribute is quite delicate. The processing
3851 -- in Sem_Attr introduced a conversion to universal real, reflecting the
3852 -- semantics of Round, but we do not want anything to do with universal
3853 -- real at runtime, since this corresponds to using floating-point
3856 -- What we have now is that the Etype of the Round attribute correctly
3857 -- indicates the final result type. The operand of the Round is the
3858 -- conversion to universal real, described above, and the operand of
3859 -- this conversion is the actual operand of Round, which may be the
3860 -- special case of a fixed point multiplication or division (Etype =
3863 -- The exapander will expand first the operand of the conversion, then
3864 -- the conversion, and finally the round attribute itself, since we
3865 -- always work inside out. But we cannot simply process naively in this
3866 -- order. In the semantic world where universal fixed and real really
3867 -- exist and have infinite precision, there is no problem, but in the
3868 -- implementation world, where universal real is a floating-point type,
3869 -- we would get the wrong result.
3871 -- So the approach is as follows. First, when expanding a multiply or
3872 -- divide whose type is universal fixed, we do nothing at all, instead
3873 -- deferring the operation till later.
3875 -- The actual processing is done in Expand_N_Type_Conversion which
3876 -- handles the special case of Round by looking at its parent to see if
3877 -- it is a Round attribute, and if it is, handling the conversion (or
3878 -- its fixed multiply/divide child) in an appropriate manner.
3880 -- This means that by the time we get to expanding the Round attribute
3881 -- itself, the Round is nothing more than a type conversion (and will
3882 -- often be a null type conversion), so we just replace it with the
3883 -- appropriate conversion operation.
3885 when Attribute_Round =>
3887 Convert_To (Etype (N), Relocate_Node (First (Exprs))));
3888 Analyze_And_Resolve (N);
3894 -- Transforms 'Rounding into a call to the floating-point attribute
3895 -- function Rounding in Fat_xxx (where xxx is the root type)
3897 when Attribute_Rounding =>
3898 Expand_Fpt_Attribute_R (N);
3904 -- Transforms 'Scaling into a call to the floating-point attribute
3905 -- function Scaling in Fat_xxx (where xxx is the root type)
3907 when Attribute_Scaling =>
3908 Expand_Fpt_Attribute_RI (N);
3914 when Attribute_Size |
3915 Attribute_Object_Size |
3916 Attribute_Value_Size |
3917 Attribute_VADS_Size => Size :
3924 -- Processing for VADS_Size case. Note that this processing removes
3925 -- all traces of VADS_Size from the tree, and completes all required
3926 -- processing for VADS_Size by translating the attribute reference
3927 -- to an appropriate Size or Object_Size reference.
3929 if Id = Attribute_VADS_Size
3930 or else (Use_VADS_Size and then Id = Attribute_Size)
3932 -- If the size is specified, then we simply use the specified
3933 -- size. This applies to both types and objects. The size of an
3934 -- object can be specified in the following ways:
3936 -- An explicit size object is given for an object
3937 -- A component size is specified for an indexed component
3938 -- A component clause is specified for a selected component
3939 -- The object is a component of a packed composite object
3941 -- If the size is specified, then VADS_Size of an object
3943 if (Is_Entity_Name (Pref)
3944 and then Present (Size_Clause (Entity (Pref))))
3946 (Nkind (Pref) = N_Component_Clause
3947 and then (Present (Component_Clause
3948 (Entity (Selector_Name (Pref))))
3949 or else Is_Packed (Etype (Prefix (Pref)))))
3951 (Nkind (Pref) = N_Indexed_Component
3952 and then (Component_Size (Etype (Prefix (Pref))) /= 0
3953 or else Is_Packed (Etype (Prefix (Pref)))))
3955 Set_Attribute_Name (N, Name_Size);
3957 -- Otherwise if we have an object rather than a type, then the
3958 -- VADS_Size attribute applies to the type of the object, rather
3959 -- than the object itself. This is one of the respects in which
3960 -- VADS_Size differs from Size.
3963 if (not Is_Entity_Name (Pref)
3964 or else not Is_Type (Entity (Pref)))
3965 and then (Is_Scalar_Type (Ptyp) or else Is_Constrained (Ptyp))
3967 Rewrite (Pref, New_Occurrence_Of (Ptyp, Loc));
3970 -- For a scalar type for which no size was explicitly given,
3971 -- VADS_Size means Object_Size. This is the other respect in
3972 -- which VADS_Size differs from Size.
3974 if Is_Scalar_Type (Ptyp) and then No (Size_Clause (Ptyp)) then
3975 Set_Attribute_Name (N, Name_Object_Size);
3977 -- In all other cases, Size and VADS_Size are the sane
3980 Set_Attribute_Name (N, Name_Size);
3985 -- For class-wide types, X'Class'Size is transformed into a direct
3986 -- reference to the Size of the class type, so that the back end does
3987 -- not have to deal with the X'Class'Size reference.
3989 if Is_Entity_Name (Pref)
3990 and then Is_Class_Wide_Type (Entity (Pref))
3992 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
3995 -- For X'Size applied to an object of a class-wide type, transform
3996 -- X'Size into a call to the primitive operation _Size applied to X.
3998 elsif Is_Class_Wide_Type (Ptyp)
3999 or else (Id = Attribute_Size
4000 and then Is_Tagged_Type (Ptyp)
4001 and then Has_Unknown_Discriminants (Ptyp))
4003 -- No need to do anything else compiling under restriction
4004 -- No_Dispatching_Calls. During the semantic analysis we
4005 -- already notified such violation.
4007 if Restriction_Active (No_Dispatching_Calls) then
4012 Make_Function_Call (Loc,
4013 Name => New_Reference_To
4014 (Find_Prim_Op (Ptyp, Name_uSize), Loc),
4015 Parameter_Associations => New_List (Pref));
4017 if Typ /= Standard_Long_Long_Integer then
4019 -- The context is a specific integer type with which the
4020 -- original attribute was compatible. The function has a
4021 -- specific type as well, so to preserve the compatibility
4022 -- we must convert explicitly.
4024 New_Node := Convert_To (Typ, New_Node);
4027 Rewrite (N, New_Node);
4028 Analyze_And_Resolve (N, Typ);
4031 -- Case of known RM_Size of a type
4033 elsif (Id = Attribute_Size or else Id = Attribute_Value_Size)
4034 and then Is_Entity_Name (Pref)
4035 and then Is_Type (Entity (Pref))
4036 and then Known_Static_RM_Size (Entity (Pref))
4038 Siz := RM_Size (Entity (Pref));
4040 -- Case of known Esize of a type
4042 elsif Id = Attribute_Object_Size
4043 and then Is_Entity_Name (Pref)
4044 and then Is_Type (Entity (Pref))
4045 and then Known_Static_Esize (Entity (Pref))
4047 Siz := Esize (Entity (Pref));
4049 -- Case of known size of object
4051 elsif Id = Attribute_Size
4052 and then Is_Entity_Name (Pref)
4053 and then Is_Object (Entity (Pref))
4054 and then Known_Esize (Entity (Pref))
4055 and then Known_Static_Esize (Entity (Pref))
4057 Siz := Esize (Entity (Pref));
4059 -- For an array component, we can do Size in the front end
4060 -- if the component_size of the array is set.
4062 elsif Nkind (Pref) = N_Indexed_Component then
4063 Siz := Component_Size (Etype (Prefix (Pref)));
4065 -- For a record component, we can do Size in the front end if there
4066 -- is a component clause, or if the record is packed and the
4067 -- component's size is known at compile time.
4069 elsif Nkind (Pref) = N_Selected_Component then
4071 Rec : constant Entity_Id := Etype (Prefix (Pref));
4072 Comp : constant Entity_Id := Entity (Selector_Name (Pref));
4075 if Present (Component_Clause (Comp)) then
4076 Siz := Esize (Comp);
4078 elsif Is_Packed (Rec) then
4079 Siz := RM_Size (Ptyp);
4082 Apply_Universal_Integer_Attribute_Checks (N);
4087 -- All other cases are handled by the back end
4090 Apply_Universal_Integer_Attribute_Checks (N);
4092 -- If Size is applied to a formal parameter that is of a packed
4093 -- array subtype, then apply Size to the actual subtype.
4095 if Is_Entity_Name (Pref)
4096 and then Is_Formal (Entity (Pref))
4097 and then Is_Array_Type (Ptyp)
4098 and then Is_Packed (Ptyp)
4101 Make_Attribute_Reference (Loc,
4103 New_Occurrence_Of (Get_Actual_Subtype (Pref), Loc),
4104 Attribute_Name => Name_Size));
4105 Analyze_And_Resolve (N, Typ);
4108 -- If Size applies to a dereference of an access to unconstrained
4109 -- packed array, the back end needs to see its unconstrained
4110 -- nominal type, but also a hint to the actual constrained type.
4112 if Nkind (Pref) = N_Explicit_Dereference
4113 and then Is_Array_Type (Ptyp)
4114 and then not Is_Constrained (Ptyp)
4115 and then Is_Packed (Ptyp)
4117 Set_Actual_Designated_Subtype (Pref,
4118 Get_Actual_Subtype (Pref));
4124 -- Common processing for record and array component case
4126 if Siz /= No_Uint and then Siz /= 0 then
4128 CS : constant Boolean := Comes_From_Source (N);
4131 Rewrite (N, Make_Integer_Literal (Loc, Siz));
4133 -- This integer literal is not a static expression. We do not
4134 -- call Analyze_And_Resolve here, because this would activate
4135 -- the circuit for deciding that a static value was out of
4136 -- range, and we don't want that.
4138 -- So just manually set the type, mark the expression as non-
4139 -- static, and then ensure that the result is checked properly
4140 -- if the attribute comes from source (if it was internally
4141 -- generated, we never need a constraint check).
4144 Set_Is_Static_Expression (N, False);
4147 Apply_Constraint_Check (N, Typ);
4157 when Attribute_Storage_Pool =>
4159 Make_Type_Conversion (Loc,
4160 Subtype_Mark => New_Reference_To (Etype (N), Loc),
4161 Expression => New_Reference_To (Entity (N), Loc)));
4162 Analyze_And_Resolve (N, Typ);
4168 when Attribute_Storage_Size => Storage_Size : begin
4170 -- Access type case, always go to the root type
4172 -- The case of access types results in a value of zero for the case
4173 -- where no storage size attribute clause has been given. If a
4174 -- storage size has been given, then the attribute is converted
4175 -- to a reference to the variable used to hold this value.
4177 if Is_Access_Type (Ptyp) then
4178 if Present (Storage_Size_Variable (Root_Type (Ptyp))) then
4180 Make_Attribute_Reference (Loc,
4181 Prefix => New_Reference_To (Typ, Loc),
4182 Attribute_Name => Name_Max,
4183 Expressions => New_List (
4184 Make_Integer_Literal (Loc, 0),
4187 (Storage_Size_Variable (Root_Type (Ptyp)), Loc)))));
4189 elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then
4192 Make_Function_Call (Loc,
4196 (Etype (Associated_Storage_Pool (Root_Type (Ptyp))),
4197 Attribute_Name (N)),
4200 Parameter_Associations => New_List (
4202 (Associated_Storage_Pool (Root_Type (Ptyp)), Loc)))));
4205 Rewrite (N, Make_Integer_Literal (Loc, 0));
4208 Analyze_And_Resolve (N, Typ);
4210 -- For tasks, we retrieve the size directly from the TCB. The
4211 -- size may depend on a discriminant of the type, and therefore
4212 -- can be a per-object expression, so type-level information is
4213 -- not sufficient in general. There are four cases to consider:
4215 -- a) If the attribute appears within a task body, the designated
4216 -- TCB is obtained by a call to Self.
4218 -- b) If the prefix of the attribute is the name of a task object,
4219 -- the designated TCB is the one stored in the corresponding record.
4221 -- c) If the prefix is a task type, the size is obtained from the
4222 -- size variable created for each task type
4224 -- d) If no storage_size was specified for the type , there is no
4225 -- size variable, and the value is a system-specific default.
4228 if In_Open_Scopes (Ptyp) then
4230 -- Storage_Size (Self)
4234 Make_Function_Call (Loc,
4236 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4237 Parameter_Associations =>
4239 Make_Function_Call (Loc,
4241 New_Reference_To (RTE (RE_Self), Loc))))));
4243 elsif not Is_Entity_Name (Pref)
4244 or else not Is_Type (Entity (Pref))
4246 -- Storage_Size (Rec (Obj).Size)
4250 Make_Function_Call (Loc,
4252 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4253 Parameter_Associations =>
4255 Make_Selected_Component (Loc,
4257 Unchecked_Convert_To (
4258 Corresponding_Record_Type (Ptyp),
4259 New_Copy_Tree (Pref)),
4261 Make_Identifier (Loc, Name_uTask_Id))))));
4263 elsif Present (Storage_Size_Variable (Ptyp)) then
4265 -- Static storage size pragma given for type: retrieve value
4266 -- from its allocated storage variable.
4270 Make_Function_Call (Loc,
4271 Name => New_Occurrence_Of (
4272 RTE (RE_Adjust_Storage_Size), Loc),
4273 Parameter_Associations =>
4276 Storage_Size_Variable (Ptyp), Loc)))));
4278 -- Get system default
4282 Make_Function_Call (Loc,
4285 RTE (RE_Default_Stack_Size), Loc))));
4288 Analyze_And_Resolve (N, Typ);
4296 when Attribute_Stream_Size =>
4298 Make_Integer_Literal (Loc, Intval => Get_Stream_Size (Ptyp)));
4299 Analyze_And_Resolve (N, Typ);
4305 -- 1. Deal with enumeration types with holes
4306 -- 2. For floating-point, generate call to attribute function
4307 -- 3. For other cases, deal with constraint checking
4309 when Attribute_Succ => Succ : declare
4310 Etyp : constant Entity_Id := Base_Type (Ptyp);
4314 -- For enumeration types with non-standard representations, we
4315 -- expand typ'Succ (x) into
4317 -- Pos_To_Rep (Rep_To_Pos (x) + 1)
4319 -- If the representation is contiguous, we compute instead
4320 -- Lit1 + Rep_to_Pos (x+1), to catch invalid representations.
4322 if Is_Enumeration_Type (Ptyp)
4323 and then Present (Enum_Pos_To_Rep (Etyp))
4325 if Has_Contiguous_Rep (Etyp) then
4327 Unchecked_Convert_To (Ptyp,
4330 Make_Integer_Literal (Loc,
4331 Enumeration_Rep (First_Literal (Ptyp))),
4333 Make_Function_Call (Loc,
4336 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4338 Parameter_Associations =>
4340 Unchecked_Convert_To (Ptyp,
4343 Unchecked_Convert_To (Standard_Integer,
4344 Relocate_Node (First (Exprs))),
4346 Make_Integer_Literal (Loc, 1))),
4347 Rep_To_Pos_Flag (Ptyp, Loc))))));
4349 -- Add Boolean parameter True, to request program errror if
4350 -- we have a bad representation on our hands. Add False if
4351 -- checks are suppressed.
4353 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
4355 Make_Indexed_Component (Loc,
4358 (Enum_Pos_To_Rep (Etyp), Loc),
4359 Expressions => New_List (
4362 Make_Function_Call (Loc,
4365 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4366 Parameter_Associations => Exprs),
4367 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
4370 Analyze_And_Resolve (N, Typ);
4372 -- For floating-point, we transform 'Succ into a call to the Succ
4373 -- floating-point attribute function in Fat_xxx (xxx is root type)
4375 elsif Is_Floating_Point_Type (Ptyp) then
4376 Expand_Fpt_Attribute_R (N);
4377 Analyze_And_Resolve (N, Typ);
4379 -- For modular types, nothing to do (no overflow, since wraps)
4381 elsif Is_Modular_Integer_Type (Ptyp) then
4384 -- For other types, if argument is marked as needing a range check or
4385 -- overflow checking is enabled, we must generate a check.
4387 elsif not Overflow_Checks_Suppressed (Ptyp)
4388 or else Do_Range_Check (First (Exprs))
4390 Set_Do_Range_Check (First (Exprs), False);
4391 Expand_Pred_Succ (N);
4399 -- Transforms X'Tag into a direct reference to the tag of X
4401 when Attribute_Tag => Tag : declare
4403 Prefix_Is_Type : Boolean;
4406 if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then
4407 Ttyp := Entity (Pref);
4408 Prefix_Is_Type := True;
4411 Prefix_Is_Type := False;
4414 if Is_Class_Wide_Type (Ttyp) then
4415 Ttyp := Root_Type (Ttyp);
4418 Ttyp := Underlying_Type (Ttyp);
4420 -- Ada 2005: The type may be a synchronized tagged type, in which
4421 -- case the tag information is stored in the corresponding record.
4423 if Is_Concurrent_Type (Ttyp) then
4424 Ttyp := Corresponding_Record_Type (Ttyp);
4427 if Prefix_Is_Type then
4429 -- For VMs we leave the type attribute unexpanded because
4430 -- there's not a dispatching table to reference.
4432 if Tagged_Type_Expansion then
4434 Unchecked_Convert_To (RTE (RE_Tag),
4436 (Node (First_Elmt (Access_Disp_Table (Ttyp))), Loc)));
4437 Analyze_And_Resolve (N, RTE (RE_Tag));
4440 -- Ada 2005 (AI-251): The use of 'Tag in the sources always
4441 -- references the primary tag of the actual object. If 'Tag is
4442 -- applied to class-wide interface objects we generate code that
4443 -- displaces "this" to reference the base of the object.
4445 elsif Comes_From_Source (N)
4446 and then Is_Class_Wide_Type (Etype (Prefix (N)))
4447 and then Is_Interface (Etype (Prefix (N)))
4450 -- (To_Tag_Ptr (Prefix'Address)).all
4452 -- Note that Prefix'Address is recursively expanded into a call
4453 -- to Base_Address (Obj.Tag)
4455 -- Not needed for VM targets, since all handled by the VM
4457 if Tagged_Type_Expansion then
4459 Make_Explicit_Dereference (Loc,
4460 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
4461 Make_Attribute_Reference (Loc,
4462 Prefix => Relocate_Node (Pref),
4463 Attribute_Name => Name_Address))));
4464 Analyze_And_Resolve (N, RTE (RE_Tag));
4469 Make_Selected_Component (Loc,
4470 Prefix => Relocate_Node (Pref),
4472 New_Reference_To (First_Tag_Component (Ttyp), Loc)));
4473 Analyze_And_Resolve (N, RTE (RE_Tag));
4481 -- Transforms 'Terminated attribute into a call to Terminated function
4483 when Attribute_Terminated => Terminated :
4485 -- The prefix of Terminated is of a task interface class-wide type.
4487 -- terminated (Task_Id (Pref._disp_get_task_id));
4489 if Ada_Version >= Ada_2005
4490 and then Ekind (Ptyp) = E_Class_Wide_Type
4491 and then Is_Interface (Ptyp)
4492 and then Is_Task_Interface (Ptyp)
4495 Make_Function_Call (Loc,
4497 New_Reference_To (RTE (RE_Terminated), Loc),
4498 Parameter_Associations => New_List (
4499 Make_Unchecked_Type_Conversion (Loc,
4501 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
4503 Make_Selected_Component (Loc,
4505 New_Copy_Tree (Pref),
4507 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
4509 elsif Restricted_Profile then
4511 Build_Call_With_Task (Pref, RTE (RE_Restricted_Terminated)));
4515 Build_Call_With_Task (Pref, RTE (RE_Terminated)));
4518 Analyze_And_Resolve (N, Standard_Boolean);
4525 -- Transforms System'To_Address (X) and System.Address'Ref (X) into
4526 -- unchecked conversion from (integral) type of X to type address.
4528 when Attribute_To_Address | Attribute_Ref =>
4530 Unchecked_Convert_To (RTE (RE_Address),
4531 Relocate_Node (First (Exprs))));
4532 Analyze_And_Resolve (N, RTE (RE_Address));
4538 when Attribute_To_Any => To_Any : declare
4539 P_Type : constant Entity_Id := Etype (Pref);
4540 Decls : constant List_Id := New_List;
4544 (Convert_To (P_Type,
4545 Relocate_Node (First (Exprs))), Decls));
4546 Insert_Actions (N, Decls);
4547 Analyze_And_Resolve (N, RTE (RE_Any));
4554 -- Transforms 'Truncation into a call to the floating-point attribute
4555 -- function Truncation in Fat_xxx (where xxx is the root type).
4556 -- Expansion is avoided for cases the back end can handle directly.
4558 when Attribute_Truncation =>
4559 if not Is_Inline_Floating_Point_Attribute (N) then
4560 Expand_Fpt_Attribute_R (N);
4567 when Attribute_TypeCode => TypeCode : declare
4568 P_Type : constant Entity_Id := Etype (Pref);
4569 Decls : constant List_Id := New_List;
4571 Rewrite (N, Build_TypeCode_Call (Loc, P_Type, Decls));
4572 Insert_Actions (N, Decls);
4573 Analyze_And_Resolve (N, RTE (RE_TypeCode));
4576 -----------------------
4577 -- Unbiased_Rounding --
4578 -----------------------
4580 -- Transforms 'Unbiased_Rounding into a call to the floating-point
4581 -- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the
4582 -- root type). Expansion is avoided for cases the back end can handle
4585 when Attribute_Unbiased_Rounding =>
4586 if not Is_Inline_Floating_Point_Attribute (N) then
4587 Expand_Fpt_Attribute_R (N);
4594 when Attribute_UET_Address => UET_Address : declare
4595 Ent : constant Entity_Id := Make_Temporary (Loc, 'T');
4599 Make_Object_Declaration (Loc,
4600 Defining_Identifier => Ent,
4601 Aliased_Present => True,
4602 Object_Definition =>
4603 New_Occurrence_Of (RTE (RE_Address), Loc)));
4605 -- Construct name __gnat_xxx__SDP, where xxx is the unit name
4606 -- in normal external form.
4608 Get_External_Unit_Name_String (Get_Unit_Name (Pref));
4609 Name_Buffer (1 + 7 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
4610 Name_Len := Name_Len + 7;
4611 Name_Buffer (1 .. 7) := "__gnat_";
4612 Name_Buffer (Name_Len + 1 .. Name_Len + 5) := "__SDP";
4613 Name_Len := Name_Len + 5;
4615 Set_Is_Imported (Ent);
4616 Set_Interface_Name (Ent,
4617 Make_String_Literal (Loc,
4618 Strval => String_From_Name_Buffer));
4620 -- Set entity as internal to ensure proper Sprint output of its
4621 -- implicit importation.
4623 Set_Is_Internal (Ent);
4626 Make_Attribute_Reference (Loc,
4627 Prefix => New_Occurrence_Of (Ent, Loc),
4628 Attribute_Name => Name_Address));
4630 Analyze_And_Resolve (N, Typ);
4637 -- The processing for VADS_Size is shared with Size
4643 -- For enumeration types with a standard representation, and for all
4644 -- other types, Val is handled by the back end. For enumeration types
4645 -- with a non-standard representation we use the _Pos_To_Rep array that
4646 -- was created when the type was frozen.
4648 when Attribute_Val => Val : declare
4649 Etyp : constant Entity_Id := Base_Type (Entity (Pref));
4652 if Is_Enumeration_Type (Etyp)
4653 and then Present (Enum_Pos_To_Rep (Etyp))
4655 if Has_Contiguous_Rep (Etyp) then
4657 Rep_Node : constant Node_Id :=
4658 Unchecked_Convert_To (Etyp,
4661 Make_Integer_Literal (Loc,
4662 Enumeration_Rep (First_Literal (Etyp))),
4664 (Convert_To (Standard_Integer,
4665 Relocate_Node (First (Exprs))))));
4669 Unchecked_Convert_To (Etyp,
4672 Make_Integer_Literal (Loc,
4673 Enumeration_Rep (First_Literal (Etyp))),
4675 Make_Function_Call (Loc,
4678 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4679 Parameter_Associations => New_List (
4681 Rep_To_Pos_Flag (Etyp, Loc))))));
4686 Make_Indexed_Component (Loc,
4687 Prefix => New_Reference_To (Enum_Pos_To_Rep (Etyp), Loc),
4688 Expressions => New_List (
4689 Convert_To (Standard_Integer,
4690 Relocate_Node (First (Exprs))))));
4693 Analyze_And_Resolve (N, Typ);
4695 -- If the argument is marked as requiring a range check then generate
4698 elsif Do_Range_Check (First (Exprs)) then
4699 Set_Do_Range_Check (First (Exprs), False);
4700 Generate_Range_Check (First (Exprs), Etyp, CE_Range_Check_Failed);
4708 -- The code for valid is dependent on the particular types involved.
4709 -- See separate sections below for the generated code in each case.
4711 when Attribute_Valid => Valid : declare
4712 Btyp : Entity_Id := Base_Type (Ptyp);
4715 Save_Validity_Checks_On : constant Boolean := Validity_Checks_On;
4716 -- Save the validity checking mode. We always turn off validity
4717 -- checking during process of 'Valid since this is one place
4718 -- where we do not want the implicit validity checks to intefere
4719 -- with the explicit validity check that the programmer is doing.
4721 function Make_Range_Test return Node_Id;
4722 -- Build the code for a range test of the form
4723 -- Btyp!(Pref) in Btyp!(Ptyp'First) .. Btyp!(Ptyp'Last)
4725 ---------------------
4726 -- Make_Range_Test --
4727 ---------------------
4729 function Make_Range_Test return Node_Id is
4730 Temp : constant Node_Id := Duplicate_Subexpr (Pref);
4733 -- The value whose validity is being checked has been captured in
4734 -- an object declaration. We certainly don't want this object to
4735 -- appear valid because the declaration initializes it!
4737 if Is_Entity_Name (Temp) then
4738 Set_Is_Known_Valid (Entity (Temp), False);
4744 Unchecked_Convert_To (Btyp, Temp),
4748 Unchecked_Convert_To (Btyp,
4749 Make_Attribute_Reference (Loc,
4750 Prefix => New_Occurrence_Of (Ptyp, Loc),
4751 Attribute_Name => Name_First)),
4753 Unchecked_Convert_To (Btyp,
4754 Make_Attribute_Reference (Loc,
4755 Prefix => New_Occurrence_Of (Ptyp, Loc),
4756 Attribute_Name => Name_Last))));
4757 end Make_Range_Test;
4759 -- Start of processing for Attribute_Valid
4762 -- Do not expand sourced code 'Valid reference in CodePeer mode,
4763 -- will be handled by the back-end directly.
4765 if CodePeer_Mode and then Comes_From_Source (N) then
4769 -- Turn off validity checks. We do not want any implicit validity
4770 -- checks to intefere with the explicit check from the attribute
4772 Validity_Checks_On := False;
4774 -- Floating-point case. This case is handled by the Valid attribute
4775 -- code in the floating-point attribute run-time library.
4777 if Is_Floating_Point_Type (Ptyp) then
4784 case Float_Rep (Btyp) is
4786 -- For vax fpt types, call appropriate routine in special
4787 -- vax floating point unit. No need to worry about loads in
4788 -- this case, since these types have no signalling NaN's.
4790 when VAX_Native => Expand_Vax_Valid (N);
4792 -- The AAMP back end handles Valid for floating-point types
4795 Analyze_And_Resolve (Pref, Ptyp);
4796 Set_Etype (N, Standard_Boolean);
4800 Find_Fat_Info (Ptyp, Ftp, Pkg);
4802 -- If the floating-point object might be unaligned, we
4803 -- need to call the special routine Unaligned_Valid,
4804 -- which makes the needed copy, being careful not to
4805 -- load the value into any floating-point register.
4806 -- The argument in this case is obj'Address (see
4807 -- Unaligned_Valid routine in Fat_Gen).
4809 if Is_Possibly_Unaligned_Object (Pref) then
4810 Expand_Fpt_Attribute
4811 (N, Pkg, Name_Unaligned_Valid,
4813 Make_Attribute_Reference (Loc,
4814 Prefix => Relocate_Node (Pref),
4815 Attribute_Name => Name_Address)));
4817 -- In the normal case where we are sure the object is
4818 -- aligned, we generate a call to Valid, and the argument
4819 -- in this case is obj'Unrestricted_Access (after
4820 -- converting obj to the right floating-point type).
4823 Expand_Fpt_Attribute
4824 (N, Pkg, Name_Valid,
4826 Make_Attribute_Reference (Loc,
4827 Prefix => Unchecked_Convert_To (Ftp, Pref),
4828 Attribute_Name => Name_Unrestricted_Access)));
4832 -- One more task, we still need a range check. Required
4833 -- only if we have a constraint, since the Valid routine
4834 -- catches infinities properly (infinities are never valid).
4836 -- The way we do the range check is simply to create the
4837 -- expression: Valid (N) and then Base_Type(Pref) in Typ.
4839 if not Subtypes_Statically_Match (Ptyp, Btyp) then
4842 Left_Opnd => Relocate_Node (N),
4845 Left_Opnd => Convert_To (Btyp, Pref),
4846 Right_Opnd => New_Occurrence_Of (Ptyp, Loc))));
4850 -- Enumeration type with holes
4852 -- For enumeration types with holes, the Pos value constructed by
4853 -- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a
4854 -- second argument of False returns minus one for an invalid value,
4855 -- and the non-negative pos value for a valid value, so the
4856 -- expansion of X'Valid is simply:
4858 -- type(X)'Pos (X) >= 0
4860 -- We can't quite generate it that way because of the requirement
4861 -- for the non-standard second argument of False in the resulting
4862 -- rep_to_pos call, so we have to explicitly create:
4864 -- _rep_to_pos (X, False) >= 0
4866 -- If we have an enumeration subtype, we also check that the
4867 -- value is in range:
4869 -- _rep_to_pos (X, False) >= 0
4871 -- (X >= type(X)'First and then type(X)'Last <= X)
4873 elsif Is_Enumeration_Type (Ptyp)
4874 and then Present (Enum_Pos_To_Rep (Base_Type (Ptyp)))
4879 Make_Function_Call (Loc,
4882 (TSS (Base_Type (Ptyp), TSS_Rep_To_Pos), Loc),
4883 Parameter_Associations => New_List (
4885 New_Occurrence_Of (Standard_False, Loc))),
4886 Right_Opnd => Make_Integer_Literal (Loc, 0));
4890 (Type_Low_Bound (Ptyp) /= Type_Low_Bound (Btyp)
4892 Type_High_Bound (Ptyp) /= Type_High_Bound (Btyp))
4894 -- The call to Make_Range_Test will create declarations
4895 -- that need a proper insertion point, but Pref is now
4896 -- attached to a node with no ancestor. Attach to tree
4897 -- even if it is to be rewritten below.
4899 Set_Parent (Tst, Parent (N));
4903 Left_Opnd => Make_Range_Test,
4909 -- Fortran convention booleans
4911 -- For the very special case of Fortran convention booleans, the
4912 -- value is always valid, since it is an integer with the semantics
4913 -- that non-zero is true, and any value is permissible.
4915 elsif Is_Boolean_Type (Ptyp)
4916 and then Convention (Ptyp) = Convention_Fortran
4918 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
4920 -- For biased representations, we will be doing an unchecked
4921 -- conversion without unbiasing the result. That means that the range
4922 -- test has to take this into account, and the proper form of the
4925 -- Btyp!(Pref) < Btyp!(Ptyp'Range_Length)
4927 elsif Has_Biased_Representation (Ptyp) then
4928 Btyp := RTE (RE_Unsigned_32);
4932 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
4934 Unchecked_Convert_To (Btyp,
4935 Make_Attribute_Reference (Loc,
4936 Prefix => New_Occurrence_Of (Ptyp, Loc),
4937 Attribute_Name => Name_Range_Length))));
4939 -- For all other scalar types, what we want logically is a
4942 -- X in type(X)'First .. type(X)'Last
4944 -- But that's precisely what won't work because of possible
4945 -- unwanted optimization (and indeed the basic motivation for
4946 -- the Valid attribute is exactly that this test does not work!)
4947 -- What will work is:
4949 -- Btyp!(X) >= Btyp!(type(X)'First)
4951 -- Btyp!(X) <= Btyp!(type(X)'Last)
4953 -- where Btyp is an integer type large enough to cover the full
4954 -- range of possible stored values (i.e. it is chosen on the basis
4955 -- of the size of the type, not the range of the values). We write
4956 -- this as two tests, rather than a range check, so that static
4957 -- evaluation will easily remove either or both of the checks if
4958 -- they can be -statically determined to be true (this happens
4959 -- when the type of X is static and the range extends to the full
4960 -- range of stored values).
4962 -- Unsigned types. Note: it is safe to consider only whether the
4963 -- subtype is unsigned, since we will in that case be doing all
4964 -- unsigned comparisons based on the subtype range. Since we use the
4965 -- actual subtype object size, this is appropriate.
4967 -- For example, if we have
4969 -- subtype x is integer range 1 .. 200;
4970 -- for x'Object_Size use 8;
4972 -- Now the base type is signed, but objects of this type are bits
4973 -- unsigned, and doing an unsigned test of the range 1 to 200 is
4974 -- correct, even though a value greater than 127 looks signed to a
4975 -- signed comparison.
4977 elsif Is_Unsigned_Type (Ptyp) then
4978 if Esize (Ptyp) <= 32 then
4979 Btyp := RTE (RE_Unsigned_32);
4981 Btyp := RTE (RE_Unsigned_64);
4984 Rewrite (N, Make_Range_Test);
4989 if Esize (Ptyp) <= Esize (Standard_Integer) then
4990 Btyp := Standard_Integer;
4992 Btyp := Universal_Integer;
4995 Rewrite (N, Make_Range_Test);
4998 Analyze_And_Resolve (N, Standard_Boolean);
4999 Validity_Checks_On := Save_Validity_Checks_On;
5006 -- Value attribute is handled in separate unit Exp_Imgv
5008 when Attribute_Value =>
5009 Exp_Imgv.Expand_Value_Attribute (N);
5015 -- The processing for Value_Size shares the processing for Size
5021 -- The processing for Version shares the processing for Body_Version
5027 -- Wide_Image attribute is handled in separate unit Exp_Imgv
5029 when Attribute_Wide_Image =>
5030 Exp_Imgv.Expand_Wide_Image_Attribute (N);
5032 ---------------------
5033 -- Wide_Wide_Image --
5034 ---------------------
5036 -- Wide_Wide_Image attribute is handled in separate unit Exp_Imgv
5038 when Attribute_Wide_Wide_Image =>
5039 Exp_Imgv.Expand_Wide_Wide_Image_Attribute (N);
5045 -- We expand typ'Wide_Value (X) into
5048 -- (Wide_String_To_String (X, Wide_Character_Encoding_Method))
5050 -- Wide_String_To_String is a runtime function that converts its wide
5051 -- string argument to String, converting any non-translatable characters
5052 -- into appropriate escape sequences. This preserves the required
5053 -- semantics of Wide_Value in all cases, and results in a very simple
5054 -- implementation approach.
5056 -- Note: for this approach to be fully standard compliant for the cases
5057 -- where typ is Wide_Character and Wide_Wide_Character, the encoding
5058 -- method must cover the entire character range (e.g. UTF-8). But that
5059 -- is a reasonable requirement when dealing with encoded character
5060 -- sequences. Presumably if one of the restrictive encoding mechanisms
5061 -- is in use such as Shift-JIS, then characters that cannot be
5062 -- represented using this encoding will not appear in any case.
5064 when Attribute_Wide_Value => Wide_Value :
5067 Make_Attribute_Reference (Loc,
5069 Attribute_Name => Name_Value,
5071 Expressions => New_List (
5072 Make_Function_Call (Loc,
5074 New_Reference_To (RTE (RE_Wide_String_To_String), Loc),
5076 Parameter_Associations => New_List (
5077 Relocate_Node (First (Exprs)),
5078 Make_Integer_Literal (Loc,
5079 Intval => Int (Wide_Character_Encoding_Method)))))));
5081 Analyze_And_Resolve (N, Typ);
5084 ---------------------
5085 -- Wide_Wide_Value --
5086 ---------------------
5088 -- We expand typ'Wide_Value_Value (X) into
5091 -- (Wide_Wide_String_To_String (X, Wide_Character_Encoding_Method))
5093 -- Wide_Wide_String_To_String is a runtime function that converts its
5094 -- wide string argument to String, converting any non-translatable
5095 -- characters into appropriate escape sequences. This preserves the
5096 -- required semantics of Wide_Wide_Value in all cases, and results in a
5097 -- very simple implementation approach.
5099 -- It's not quite right where typ = Wide_Wide_Character, because the
5100 -- encoding method may not cover the whole character type ???
5102 when Attribute_Wide_Wide_Value => Wide_Wide_Value :
5105 Make_Attribute_Reference (Loc,
5107 Attribute_Name => Name_Value,
5109 Expressions => New_List (
5110 Make_Function_Call (Loc,
5112 New_Reference_To (RTE (RE_Wide_Wide_String_To_String), Loc),
5114 Parameter_Associations => New_List (
5115 Relocate_Node (First (Exprs)),
5116 Make_Integer_Literal (Loc,
5117 Intval => Int (Wide_Character_Encoding_Method)))))));
5119 Analyze_And_Resolve (N, Typ);
5120 end Wide_Wide_Value;
5122 ---------------------
5123 -- Wide_Wide_Width --
5124 ---------------------
5126 -- Wide_Wide_Width attribute is handled in separate unit Exp_Imgv
5128 when Attribute_Wide_Wide_Width =>
5129 Exp_Imgv.Expand_Width_Attribute (N, Wide_Wide);
5135 -- Wide_Width attribute is handled in separate unit Exp_Imgv
5137 when Attribute_Wide_Width =>
5138 Exp_Imgv.Expand_Width_Attribute (N, Wide);
5144 -- Width attribute is handled in separate unit Exp_Imgv
5146 when Attribute_Width =>
5147 Exp_Imgv.Expand_Width_Attribute (N, Normal);
5153 when Attribute_Write => Write : declare
5154 P_Type : constant Entity_Id := Entity (Pref);
5155 U_Type : constant Entity_Id := Underlying_Type (P_Type);
5163 -- If no underlying type, we have an error that will be diagnosed
5164 -- elsewhere, so here we just completely ignore the expansion.
5170 -- The simple case, if there is a TSS for Write, just call it
5172 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Write);
5174 if Present (Pname) then
5178 -- If there is a Stream_Convert pragma, use it, we rewrite
5180 -- sourcetyp'Output (stream, Item)
5184 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
5186 -- where strmwrite is the given Write function that converts an
5187 -- argument of type sourcetyp or a type acctyp, from which it is
5188 -- derived to type strmtyp. The conversion to acttyp is required
5189 -- for the derived case.
5191 Prag := Get_Stream_Convert_Pragma (P_Type);
5193 if Present (Prag) then
5195 Next (Next (First (Pragma_Argument_Associations (Prag))));
5196 Wfunc := Entity (Expression (Arg3));
5199 Make_Attribute_Reference (Loc,
5200 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
5201 Attribute_Name => Name_Output,
5202 Expressions => New_List (
5203 Relocate_Node (First (Exprs)),
5204 Make_Function_Call (Loc,
5205 Name => New_Occurrence_Of (Wfunc, Loc),
5206 Parameter_Associations => New_List (
5207 OK_Convert_To (Etype (First_Formal (Wfunc)),
5208 Relocate_Node (Next (First (Exprs)))))))));
5213 -- For elementary types, we call the W_xxx routine directly
5215 elsif Is_Elementary_Type (U_Type) then
5216 Rewrite (N, Build_Elementary_Write_Call (N));
5222 elsif Is_Array_Type (U_Type) then
5223 Build_Array_Write_Procedure (N, U_Type, Decl, Pname);
5224 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
5226 -- Tagged type case, use the primitive Write function. Note that
5227 -- this will dispatch in the class-wide case which is what we want
5229 elsif Is_Tagged_Type (U_Type) then
5230 Pname := Find_Prim_Op (U_Type, TSS_Stream_Write);
5232 -- All other record type cases, including protected records.
5233 -- The latter only arise for expander generated code for
5234 -- handling shared passive partition access.
5238 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
5240 -- Ada 2005 (AI-216): Program_Error is raised when executing
5241 -- the default implementation of the Write attribute of an
5242 -- Unchecked_Union type. However, if the 'Write reference is
5243 -- within the generated Output stream procedure, Write outputs
5244 -- the components, and the default values of the discriminant
5245 -- are streamed by the Output procedure itself.
5247 if Is_Unchecked_Union (Base_Type (U_Type))
5248 and not Is_TSS (Current_Scope, TSS_Stream_Output)
5251 Make_Raise_Program_Error (Loc,
5252 Reason => PE_Unchecked_Union_Restriction));
5255 if Has_Discriminants (U_Type)
5257 (Discriminant_Default_Value (First_Discriminant (U_Type)))
5259 Build_Mutable_Record_Write_Procedure
5260 (Loc, Full_Base (U_Type), Decl, Pname);
5262 Build_Record_Write_Procedure
5263 (Loc, Full_Base (U_Type), Decl, Pname);
5266 Insert_Action (N, Decl);
5270 -- If we fall through, Pname is the procedure to be called
5272 Rewrite_Stream_Proc_Call (Pname);
5275 -- Component_Size is handled by the back end, unless the component size
5276 -- is known at compile time, which is always true in the packed array
5277 -- case. It is important that the packed array case is handled in the
5278 -- front end (see Eval_Attribute) since the back end would otherwise get
5279 -- confused by the equivalent packed array type.
5281 when Attribute_Component_Size =>
5284 -- The following attributes are handled by the back end (except that
5285 -- static cases have already been evaluated during semantic processing,
5286 -- but in any case the back end should not count on this). The one bit
5287 -- of special processing required is that these attributes typically
5288 -- generate conditionals in the code, so we need to check the relevant
5291 when Attribute_Max |
5293 Check_Restriction (No_Implicit_Conditionals, N);
5295 -- The following attributes are handled by the back end (except that
5296 -- static cases have already been evaluated during semantic processing,
5297 -- but in any case the back end should not count on this).
5299 -- The back end also handles the non-class-wide cases of Size
5301 when Attribute_Bit_Order |
5302 Attribute_Code_Address |
5303 Attribute_Definite |
5304 Attribute_Null_Parameter |
5305 Attribute_Passed_By_Reference |
5306 Attribute_Pool_Address =>
5309 -- The following attributes are also handled by the back end, but return
5310 -- a universal integer result, so may need a conversion for checking
5311 -- that the result is in range.
5313 when Attribute_Aft |
5314 Attribute_Max_Alignment_For_Allocation |
5315 Attribute_Max_Size_In_Storage_Elements =>
5316 Apply_Universal_Integer_Attribute_Checks (N);
5318 -- The following attributes should not appear at this stage, since they
5319 -- have already been handled by the analyzer (and properly rewritten
5320 -- with corresponding values or entities to represent the right values)
5322 when Attribute_Abort_Signal |
5323 Attribute_Address_Size |
5326 Attribute_Compiler_Version |
5327 Attribute_Default_Bit_Order |
5334 Attribute_Fast_Math |
5335 Attribute_Has_Access_Values |
5336 Attribute_Has_Discriminants |
5337 Attribute_Has_Tagged_Values |
5339 Attribute_Machine_Emax |
5340 Attribute_Machine_Emin |
5341 Attribute_Machine_Mantissa |
5342 Attribute_Machine_Overflows |
5343 Attribute_Machine_Radix |
5344 Attribute_Machine_Rounds |
5345 Attribute_Maximum_Alignment |
5346 Attribute_Model_Emin |
5347 Attribute_Model_Epsilon |
5348 Attribute_Model_Mantissa |
5349 Attribute_Model_Small |
5351 Attribute_Partition_ID |
5353 Attribute_Safe_Emax |
5354 Attribute_Safe_First |
5355 Attribute_Safe_Large |
5356 Attribute_Safe_Last |
5357 Attribute_Safe_Small |
5359 Attribute_Signed_Zeros |
5361 Attribute_Storage_Unit |
5362 Attribute_Stub_Type |
5363 Attribute_Target_Name |
5364 Attribute_Type_Class |
5365 Attribute_Type_Key |
5366 Attribute_Unconstrained_Array |
5367 Attribute_Universal_Literal_String |
5368 Attribute_Wchar_T_Size |
5369 Attribute_Word_Size =>
5370 raise Program_Error;
5372 -- The Asm_Input and Asm_Output attributes are not expanded at this
5373 -- stage, but will be eliminated in the expansion of the Asm call, see
5374 -- Exp_Intr for details. So the back end will never see these either.
5376 when Attribute_Asm_Input |
5377 Attribute_Asm_Output =>
5382 when RE_Not_Available =>
5384 end Expand_N_Attribute_Reference;
5386 ----------------------
5387 -- Expand_Pred_Succ --
5388 ----------------------
5390 -- For typ'Pred (exp), we generate the check
5392 -- [constraint_error when exp = typ'Base'First]
5394 -- Similarly, for typ'Succ (exp), we generate the check
5396 -- [constraint_error when exp = typ'Base'Last]
5398 -- These checks are not generated for modular types, since the proper
5399 -- semantics for Succ and Pred on modular types is to wrap, not raise CE.
5400 -- We also suppress these checks if we are the right side of an assignment
5401 -- statement or the expression of an object declaration, where the flag
5402 -- Suppress_Assignment_Checks is set for the assignment/declaration.
5404 procedure Expand_Pred_Succ (N : Node_Id) is
5405 Loc : constant Source_Ptr := Sloc (N);
5406 P : constant Node_Id := Parent (N);
5410 if Attribute_Name (N) = Name_Pred then
5416 if not Nkind_In (P, N_Assignment_Statement, N_Object_Declaration)
5417 or else not Suppress_Assignment_Checks (P)
5420 Make_Raise_Constraint_Error (Loc,
5424 Duplicate_Subexpr_Move_Checks (First (Expressions (N))),
5426 Make_Attribute_Reference (Loc,
5428 New_Reference_To (Base_Type (Etype (Prefix (N))), Loc),
5429 Attribute_Name => Cnam)),
5430 Reason => CE_Overflow_Check_Failed));
5432 end Expand_Pred_Succ;
5438 procedure Find_Fat_Info
5440 Fat_Type : out Entity_Id;
5441 Fat_Pkg : out RE_Id)
5443 Btyp : constant Entity_Id := Base_Type (T);
5444 Rtyp : constant Entity_Id := Root_Type (T);
5445 Digs : constant Nat := UI_To_Int (Digits_Value (Btyp));
5448 -- If the base type is VAX float, then get appropriate VAX float type
5450 if Vax_Float (Btyp) then
5453 Fat_Type := RTE (RE_Fat_VAX_F);
5454 Fat_Pkg := RE_Attr_VAX_F_Float;
5457 Fat_Type := RTE (RE_Fat_VAX_D);
5458 Fat_Pkg := RE_Attr_VAX_D_Float;
5461 Fat_Type := RTE (RE_Fat_VAX_G);
5462 Fat_Pkg := RE_Attr_VAX_G_Float;
5465 raise Program_Error;
5468 -- If root type is VAX float, this is the case where the library has
5469 -- been recompiled in VAX float mode, and we have an IEEE float type.
5470 -- This is when we use the special IEEE Fat packages.
5472 elsif Vax_Float (Rtyp) then
5475 Fat_Type := RTE (RE_Fat_IEEE_Short);
5476 Fat_Pkg := RE_Attr_IEEE_Short;
5479 Fat_Type := RTE (RE_Fat_IEEE_Long);
5480 Fat_Pkg := RE_Attr_IEEE_Long;
5483 raise Program_Error;
5486 -- If neither the base type nor the root type is VAX_Native then VAX
5487 -- float is out of the picture, and we can just use the root type.
5492 if Fat_Type = Standard_Short_Float then
5493 Fat_Pkg := RE_Attr_Short_Float;
5495 elsif Fat_Type = Standard_Float then
5496 Fat_Pkg := RE_Attr_Float;
5498 elsif Fat_Type = Standard_Long_Float then
5499 Fat_Pkg := RE_Attr_Long_Float;
5501 elsif Fat_Type = Standard_Long_Long_Float then
5502 Fat_Pkg := RE_Attr_Long_Long_Float;
5504 -- Universal real (which is its own root type) is treated as being
5505 -- equivalent to Standard.Long_Long_Float, since it is defined to
5506 -- have the same precision as the longest Float type.
5508 elsif Fat_Type = Universal_Real then
5509 Fat_Type := Standard_Long_Long_Float;
5510 Fat_Pkg := RE_Attr_Long_Long_Float;
5513 raise Program_Error;
5518 ----------------------------
5519 -- Find_Stream_Subprogram --
5520 ----------------------------
5522 function Find_Stream_Subprogram
5524 Nam : TSS_Name_Type) return Entity_Id
5526 Base_Typ : constant Entity_Id := Base_Type (Typ);
5527 Ent : constant Entity_Id := TSS (Typ, Nam);
5529 function Is_Available (Entity : RE_Id) return Boolean;
5530 pragma Inline (Is_Available);
5531 -- Function to check whether the specified run-time call is available
5532 -- in the run time used. In the case of a configurable run time, it
5533 -- is normal that some subprograms are not there.
5535 -- I don't understand this routine at all, why is this not just a
5536 -- call to RTE_Available? And if for some reason we need a different
5537 -- routine with different semantics, why is not in Rtsfind ???
5543 function Is_Available (Entity : RE_Id) return Boolean is
5545 -- Assume that the unit will always be available when using a
5546 -- "normal" (not configurable) run time.
5548 return not Configurable_Run_Time_Mode
5549 or else RTE_Available (Entity);
5552 -- Start of processing for Find_Stream_Subprogram
5555 if Present (Ent) then
5559 -- Stream attributes for strings are expanded into library calls. The
5560 -- following checks are disabled when the run-time is not available or
5561 -- when compiling predefined types due to bootstrap issues. As a result,
5562 -- the compiler will generate in-place stream routines for string types
5563 -- that appear in GNAT's library, but will generate calls via rtsfind
5564 -- to library routines for user code.
5566 -- ??? For now, disable this code for JVM, since this generates a
5567 -- VerifyError exception at run time on e.g. c330001.
5569 -- This is disabled for AAMP, to avoid creating dependences on files not
5570 -- supported in the AAMP library (such as s-fileio.adb).
5572 -- Note: In the case of using a configurable run time, it is very likely
5573 -- that stream routines for string types are not present (they require
5574 -- file system support). In this case, the specific stream routines for
5575 -- strings are not used, relying on the regular stream mechanism
5576 -- instead. That is why we include the test Is_Available when dealing
5577 -- with these cases.
5579 if VM_Target /= JVM_Target
5580 and then not AAMP_On_Target
5582 not Is_Predefined_File_Name (Unit_File_Name (Current_Sem_Unit))
5584 -- String as defined in package Ada
5586 if Base_Typ = Standard_String then
5587 if Restriction_Active (No_Stream_Optimizations) then
5588 if Nam = TSS_Stream_Input
5589 and then Is_Available (RE_String_Input)
5591 return RTE (RE_String_Input);
5593 elsif Nam = TSS_Stream_Output
5594 and then Is_Available (RE_String_Output)
5596 return RTE (RE_String_Output);
5598 elsif Nam = TSS_Stream_Read
5599 and then Is_Available (RE_String_Read)
5601 return RTE (RE_String_Read);
5603 elsif Nam = TSS_Stream_Write
5604 and then Is_Available (RE_String_Write)
5606 return RTE (RE_String_Write);
5608 elsif Nam /= TSS_Stream_Input and then
5609 Nam /= TSS_Stream_Output and then
5610 Nam /= TSS_Stream_Read and then
5611 Nam /= TSS_Stream_Write
5613 raise Program_Error;
5617 if Nam = TSS_Stream_Input
5618 and then Is_Available (RE_String_Input_Blk_IO)
5620 return RTE (RE_String_Input_Blk_IO);
5622 elsif Nam = TSS_Stream_Output
5623 and then Is_Available (RE_String_Output_Blk_IO)
5625 return RTE (RE_String_Output_Blk_IO);
5627 elsif Nam = TSS_Stream_Read
5628 and then Is_Available (RE_String_Read_Blk_IO)
5630 return RTE (RE_String_Read_Blk_IO);
5632 elsif Nam = TSS_Stream_Write
5633 and then Is_Available (RE_String_Write_Blk_IO)
5635 return RTE (RE_String_Write_Blk_IO);
5637 elsif Nam /= TSS_Stream_Input and then
5638 Nam /= TSS_Stream_Output and then
5639 Nam /= TSS_Stream_Read and then
5640 Nam /= TSS_Stream_Write
5642 raise Program_Error;
5646 -- Wide_String as defined in package Ada
5648 elsif Base_Typ = Standard_Wide_String then
5649 if Restriction_Active (No_Stream_Optimizations) then
5650 if Nam = TSS_Stream_Input
5651 and then Is_Available (RE_Wide_String_Input)
5653 return RTE (RE_Wide_String_Input);
5655 elsif Nam = TSS_Stream_Output
5656 and then Is_Available (RE_Wide_String_Output)
5658 return RTE (RE_Wide_String_Output);
5660 elsif Nam = TSS_Stream_Read
5661 and then Is_Available (RE_Wide_String_Read)
5663 return RTE (RE_Wide_String_Read);
5665 elsif Nam = TSS_Stream_Write
5666 and then Is_Available (RE_Wide_String_Write)
5668 return RTE (RE_Wide_String_Write);
5670 elsif Nam /= TSS_Stream_Input and then
5671 Nam /= TSS_Stream_Output and then
5672 Nam /= TSS_Stream_Read and then
5673 Nam /= TSS_Stream_Write
5675 raise Program_Error;
5679 if Nam = TSS_Stream_Input
5680 and then Is_Available (RE_Wide_String_Input_Blk_IO)
5682 return RTE (RE_Wide_String_Input_Blk_IO);
5684 elsif Nam = TSS_Stream_Output
5685 and then Is_Available (RE_Wide_String_Output_Blk_IO)
5687 return RTE (RE_Wide_String_Output_Blk_IO);
5689 elsif Nam = TSS_Stream_Read
5690 and then Is_Available (RE_Wide_String_Read_Blk_IO)
5692 return RTE (RE_Wide_String_Read_Blk_IO);
5694 elsif Nam = TSS_Stream_Write
5695 and then Is_Available (RE_Wide_String_Write_Blk_IO)
5697 return RTE (RE_Wide_String_Write_Blk_IO);
5699 elsif Nam /= TSS_Stream_Input and then
5700 Nam /= TSS_Stream_Output and then
5701 Nam /= TSS_Stream_Read and then
5702 Nam /= TSS_Stream_Write
5704 raise Program_Error;
5708 -- Wide_Wide_String as defined in package Ada
5710 elsif Base_Typ = Standard_Wide_Wide_String then
5711 if Restriction_Active (No_Stream_Optimizations) then
5712 if Nam = TSS_Stream_Input
5713 and then Is_Available (RE_Wide_Wide_String_Input)
5715 return RTE (RE_Wide_Wide_String_Input);
5717 elsif Nam = TSS_Stream_Output
5718 and then Is_Available (RE_Wide_Wide_String_Output)
5720 return RTE (RE_Wide_Wide_String_Output);
5722 elsif Nam = TSS_Stream_Read
5723 and then Is_Available (RE_Wide_Wide_String_Read)
5725 return RTE (RE_Wide_Wide_String_Read);
5727 elsif Nam = TSS_Stream_Write
5728 and then Is_Available (RE_Wide_Wide_String_Write)
5730 return RTE (RE_Wide_Wide_String_Write);
5732 elsif Nam /= TSS_Stream_Input and then
5733 Nam /= TSS_Stream_Output and then
5734 Nam /= TSS_Stream_Read and then
5735 Nam /= TSS_Stream_Write
5737 raise Program_Error;
5741 if Nam = TSS_Stream_Input
5742 and then Is_Available (RE_Wide_Wide_String_Input_Blk_IO)
5744 return RTE (RE_Wide_Wide_String_Input_Blk_IO);
5746 elsif Nam = TSS_Stream_Output
5747 and then Is_Available (RE_Wide_Wide_String_Output_Blk_IO)
5749 return RTE (RE_Wide_Wide_String_Output_Blk_IO);
5751 elsif Nam = TSS_Stream_Read
5752 and then Is_Available (RE_Wide_Wide_String_Read_Blk_IO)
5754 return RTE (RE_Wide_Wide_String_Read_Blk_IO);
5756 elsif Nam = TSS_Stream_Write
5757 and then Is_Available (RE_Wide_Wide_String_Write_Blk_IO)
5759 return RTE (RE_Wide_Wide_String_Write_Blk_IO);
5761 elsif Nam /= TSS_Stream_Input and then
5762 Nam /= TSS_Stream_Output and then
5763 Nam /= TSS_Stream_Read and then
5764 Nam /= TSS_Stream_Write
5766 raise Program_Error;
5772 if Is_Tagged_Type (Typ)
5773 and then Is_Derived_Type (Typ)
5775 return Find_Prim_Op (Typ, Nam);
5777 return Find_Inherited_TSS (Typ, Nam);
5779 end Find_Stream_Subprogram;
5785 function Full_Base (T : Entity_Id) return Entity_Id is
5789 BT := Base_Type (T);
5791 if Is_Private_Type (BT)
5792 and then Present (Full_View (BT))
5794 BT := Full_View (BT);
5800 -----------------------
5801 -- Get_Index_Subtype --
5802 -----------------------
5804 function Get_Index_Subtype (N : Node_Id) return Node_Id is
5805 P_Type : Entity_Id := Etype (Prefix (N));
5810 if Is_Access_Type (P_Type) then
5811 P_Type := Designated_Type (P_Type);
5814 if No (Expressions (N)) then
5817 J := UI_To_Int (Expr_Value (First (Expressions (N))));
5820 Indx := First_Index (P_Type);
5826 return Etype (Indx);
5827 end Get_Index_Subtype;
5829 -------------------------------
5830 -- Get_Stream_Convert_Pragma --
5831 -------------------------------
5833 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id is
5838 -- Note: we cannot use Get_Rep_Pragma here because of the peculiarity
5839 -- that a stream convert pragma for a tagged type is not inherited from
5840 -- its parent. Probably what is wrong here is that it is basically
5841 -- incorrect to consider a stream convert pragma to be a representation
5842 -- pragma at all ???
5844 N := First_Rep_Item (Implementation_Base_Type (T));
5845 while Present (N) loop
5846 if Nkind (N) = N_Pragma
5847 and then Pragma_Name (N) = Name_Stream_Convert
5849 -- For tagged types this pragma is not inherited, so we
5850 -- must verify that it is defined for the given type and
5854 Entity (Expression (First (Pragma_Argument_Associations (N))));
5856 if not Is_Tagged_Type (T)
5858 or else (Is_Private_Type (Typ) and then T = Full_View (Typ))
5868 end Get_Stream_Convert_Pragma;
5870 ---------------------------------
5871 -- Is_Constrained_Packed_Array --
5872 ---------------------------------
5874 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean is
5875 Arr : Entity_Id := Typ;
5878 if Is_Access_Type (Arr) then
5879 Arr := Designated_Type (Arr);
5882 return Is_Array_Type (Arr)
5883 and then Is_Constrained (Arr)
5884 and then Present (Packed_Array_Type (Arr));
5885 end Is_Constrained_Packed_Array;
5887 ----------------------------------------
5888 -- Is_Inline_Floating_Point_Attribute --
5889 ----------------------------------------
5891 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean is
5892 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
5895 if Nkind (Parent (N)) /= N_Type_Conversion
5896 or else not Is_Integer_Type (Etype (Parent (N)))
5901 -- Should also support 'Machine_Rounding and 'Unbiased_Rounding, but
5902 -- required back end support has not been implemented yet ???
5904 return Id = Attribute_Truncation;
5905 end Is_Inline_Floating_Point_Attribute;
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