1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2008, 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 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Exp_Atag; use Exp_Atag;
32 with Exp_Ch2; use Exp_Ch2;
33 with Exp_Ch3; use Exp_Ch3;
34 with Exp_Ch6; use Exp_Ch6;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Dist; use Exp_Dist;
37 with Exp_Imgv; use Exp_Imgv;
38 with Exp_Pakd; use Exp_Pakd;
39 with Exp_Strm; use Exp_Strm;
40 with Exp_Tss; use Exp_Tss;
41 with Exp_Util; use Exp_Util;
42 with Exp_VFpt; use Exp_VFpt;
43 with Fname; use Fname;
44 with Freeze; use Freeze;
45 with Gnatvsn; use Gnatvsn;
46 with Itypes; use Itypes;
48 with Namet; use Namet;
49 with Nmake; use Nmake;
50 with Nlists; use Nlists;
52 with Restrict; use Restrict;
53 with Rident; use Rident;
54 with Rtsfind; use Rtsfind;
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. indices) 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
99 -- An attribute reference to a protected subprogram is transformed into
100 -- a pair of pointers: one to the object, and one to the operations.
101 -- This expansion is performed for 'Access and for 'Unrestricted_Access.
103 procedure Expand_Fpt_Attribute
108 -- This procedure expands a call to a floating-point attribute function.
109 -- N is the attribute reference node, and Args is a list of arguments to
110 -- be passed to the function call. Pkg identifies the package containing
111 -- the appropriate instantiation of System.Fat_Gen. Float arguments in Args
112 -- have already been converted to the floating-point type for which Pkg was
113 -- instantiated. The Nam argument is the relevant attribute processing
114 -- routine to be called. This is the same as the attribute name, except in
115 -- the Unaligned_Valid case.
117 procedure Expand_Fpt_Attribute_R (N : Node_Id);
118 -- This procedure expands a call to a floating-point attribute function
119 -- that takes a single floating-point argument. The function to be called
120 -- is always the same as the attribute name.
122 procedure Expand_Fpt_Attribute_RI (N : Node_Id);
123 -- This procedure expands a call to a floating-point attribute function
124 -- that takes one floating-point argument and one integer argument. The
125 -- function to be called is always the same as the attribute name.
127 procedure Expand_Fpt_Attribute_RR (N : Node_Id);
128 -- This procedure expands a call to a floating-point attribute function
129 -- that takes two floating-point arguments. The function to be called
130 -- is always the same as the attribute name.
132 procedure Expand_Pred_Succ (N : Node_Id);
133 -- Handles expansion of Pred or Succ attributes for case of non-real
134 -- operand with overflow checking required.
136 function Get_Index_Subtype (N : Node_Id) return Entity_Id;
137 -- Used for Last, Last, and Length, when the prefix is an array type.
138 -- Obtains the corresponding index subtype.
140 procedure Find_Fat_Info
142 Fat_Type : out Entity_Id;
143 Fat_Pkg : out RE_Id);
144 -- Given a floating-point type T, identifies the package containing the
145 -- attributes for this type (returned in Fat_Pkg), and the corresponding
146 -- type for which this package was instantiated from Fat_Gen. Error if T
147 -- is not a floating-point type.
149 function Find_Stream_Subprogram
151 Nam : TSS_Name_Type) return Entity_Id;
152 -- Returns the stream-oriented subprogram attribute for Typ. For tagged
153 -- types, the corresponding primitive operation is looked up, else the
154 -- appropriate TSS from the type itself, or from its closest ancestor
155 -- defining it, is returned. In both cases, inheritance of representation
156 -- aspects is thus taken into account.
158 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id;
159 -- Given a type, find a corresponding stream convert pragma that applies to
160 -- the implementation base type of this type (Typ). If found, return the
161 -- pragma node, otherwise return Empty if no pragma is found.
163 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean;
164 -- Utility for array attributes, returns true on packed constrained
165 -- arrays, and on access to same.
167 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean;
168 -- Returns true iff the given node refers to an attribute call that
169 -- can be expanded directly by the back end and does not need front end
170 -- expansion. Typically used for rounding and truncation attributes that
171 -- appear directly inside a conversion to integer.
173 ----------------------------------
174 -- Compile_Stream_Body_In_Scope --
175 ----------------------------------
177 procedure Compile_Stream_Body_In_Scope
183 Installed : Boolean := False;
184 Scop : constant Entity_Id := Scope (Arr);
185 Curr : constant Entity_Id := Current_Scope;
189 and then not In_Open_Scopes (Scop)
190 and then Ekind (Scop) = E_Package
193 Install_Visible_Declarations (Scop);
194 Install_Private_Declarations (Scop);
197 -- The entities in the package are now visible, but the generated
198 -- stream entity must appear in the current scope (usually an
199 -- enclosing stream function) so that itypes all have their proper
206 Insert_Action (N, Decl);
208 Insert_Action (N, Decl, Suppress => All_Checks);
213 -- Remove extra copy of current scope, and package itself
216 End_Package_Scope (Scop);
218 end Compile_Stream_Body_In_Scope;
220 -----------------------------------
221 -- Expand_Access_To_Protected_Op --
222 -----------------------------------
224 procedure Expand_Access_To_Protected_Op
229 -- The value of the attribute_reference is a record containing two
230 -- fields: an access to the protected object, and an access to the
231 -- subprogram itself. The prefix is a selected component.
233 Loc : constant Source_Ptr := Sloc (N);
235 Btyp : constant Entity_Id := Base_Type (Typ);
237 E_T : constant Entity_Id := Equivalent_Type (Btyp);
238 Acc : constant Entity_Id :=
239 Etype (Next_Component (First_Component (E_T)));
243 function May_Be_External_Call return Boolean;
244 -- If the 'Access is to a local operation, but appears in a context
245 -- where it may lead to a call from outside the object, we must treat
246 -- this as an external call. Clearly we cannot tell without full
247 -- flow analysis, and a subsequent call that uses this 'Access may
248 -- lead to a bounded error (trying to seize locks twice, e.g.). For
249 -- now we treat 'Access as a potential external call if it is an actual
250 -- in a call to an outside subprogram.
252 --------------------------
253 -- May_Be_External_Call --
254 --------------------------
256 function May_Be_External_Call return Boolean is
258 Par : Node_Id := Parent (N);
261 -- Account for the case where the Access attribute is part of a
262 -- named parameter association.
264 if Nkind (Par) = N_Parameter_Association then
268 if Nkind_In (Par, N_Procedure_Call_Statement, N_Function_Call)
269 and then Is_Entity_Name (Name (Par))
271 Subp := Entity (Name (Par));
272 return not In_Open_Scopes (Scope (Subp));
276 end May_Be_External_Call;
278 -- Start of processing for Expand_Access_To_Protected_Op
281 -- Within the body of the protected type, the prefix
282 -- designates a local operation, and the object is the first
283 -- parameter of the corresponding protected body of the
284 -- current enclosing operation.
286 if Is_Entity_Name (Pref) then
287 if May_Be_External_Call then
290 (External_Subprogram (Entity (Pref)), Loc);
294 (Protected_Body_Subprogram (Entity (Pref)), Loc);
297 -- Don't traverse the scopes when the attribute occurs within an init
298 -- proc, because we directly use the _init formal of the init proc in
301 Curr := Current_Scope;
302 if not Is_Init_Proc (Curr) then
303 pragma Assert (In_Open_Scopes (Scope (Entity (Pref))));
305 while Scope (Curr) /= Scope (Entity (Pref)) loop
306 Curr := Scope (Curr);
310 -- In case of protected entries the first formal of its Protected_
311 -- Body_Subprogram is the address of the object.
313 if Ekind (Curr) = E_Entry then
317 (Protected_Body_Subprogram (Curr)), Loc);
319 -- If the current scope is an init proc, then use the address of the
320 -- _init formal as the object reference.
322 elsif Is_Init_Proc (Curr) then
324 Make_Attribute_Reference (Loc,
325 Prefix => New_Occurrence_Of (First_Formal (Curr), Loc),
326 Attribute_Name => Name_Address);
328 -- In case of protected subprograms the first formal of its
329 -- Protected_Body_Subprogram is the object and we get its address.
333 Make_Attribute_Reference (Loc,
337 (Protected_Body_Subprogram (Curr)), Loc),
338 Attribute_Name => Name_Address);
341 -- Case where the prefix is not an entity name. Find the
342 -- version of the protected operation to be called from
343 -- outside the protected object.
349 (Entity (Selector_Name (Pref))), Loc);
352 Make_Attribute_Reference (Loc,
353 Prefix => Relocate_Node (Prefix (Pref)),
354 Attribute_Name => Name_Address);
362 Unchecked_Convert_To (Acc,
363 Make_Attribute_Reference (Loc,
365 Attribute_Name => Name_Address))));
369 Analyze_And_Resolve (N, E_T);
371 -- For subsequent analysis, the node must retain its type.
372 -- The backend will replace it with the equivalent type where
376 end Expand_Access_To_Protected_Op;
378 --------------------------
379 -- Expand_Fpt_Attribute --
380 --------------------------
382 procedure Expand_Fpt_Attribute
388 Loc : constant Source_Ptr := Sloc (N);
389 Typ : constant Entity_Id := Etype (N);
393 -- The function name is the selected component Attr_xxx.yyy where
394 -- Attr_xxx is the package name, and yyy is the argument Nam.
396 -- Note: it would be more usual to have separate RE entries for each
397 -- of the entities in the Fat packages, but first they have identical
398 -- names (so we would have to have lots of renaming declarations to
399 -- meet the normal RE rule of separate names for all runtime entities),
400 -- and second there would be an awful lot of them!
403 Make_Selected_Component (Loc,
404 Prefix => New_Reference_To (RTE (Pkg), Loc),
405 Selector_Name => Make_Identifier (Loc, Nam));
407 -- The generated call is given the provided set of parameters, and then
408 -- wrapped in a conversion which converts the result to the target type
409 -- We use the base type as the target because a range check may be
413 Unchecked_Convert_To (Base_Type (Etype (N)),
414 Make_Function_Call (Loc,
416 Parameter_Associations => Args)));
418 Analyze_And_Resolve (N, Typ);
419 end Expand_Fpt_Attribute;
421 ----------------------------
422 -- Expand_Fpt_Attribute_R --
423 ----------------------------
425 -- The single argument is converted to its root type to call the
426 -- appropriate runtime function, with the actual call being built
427 -- by Expand_Fpt_Attribute
429 procedure Expand_Fpt_Attribute_R (N : Node_Id) is
430 E1 : constant Node_Id := First (Expressions (N));
434 Find_Fat_Info (Etype (E1), Ftp, Pkg);
436 (N, Pkg, Attribute_Name (N),
437 New_List (Unchecked_Convert_To (Ftp, Relocate_Node (E1))));
438 end Expand_Fpt_Attribute_R;
440 -----------------------------
441 -- Expand_Fpt_Attribute_RI --
442 -----------------------------
444 -- The first argument is converted to its root type and the second
445 -- argument is converted to standard long long integer to call the
446 -- appropriate runtime function, with the actual call being built
447 -- by Expand_Fpt_Attribute
449 procedure Expand_Fpt_Attribute_RI (N : Node_Id) is
450 E1 : constant Node_Id := First (Expressions (N));
453 E2 : constant Node_Id := Next (E1);
455 Find_Fat_Info (Etype (E1), Ftp, Pkg);
457 (N, Pkg, Attribute_Name (N),
459 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
460 Unchecked_Convert_To (Standard_Integer, Relocate_Node (E2))));
461 end Expand_Fpt_Attribute_RI;
463 -----------------------------
464 -- Expand_Fpt_Attribute_RR --
465 -----------------------------
467 -- The two arguments are converted to their root types to call the
468 -- appropriate runtime function, with the actual call being built
469 -- by Expand_Fpt_Attribute
471 procedure Expand_Fpt_Attribute_RR (N : Node_Id) is
472 E1 : constant Node_Id := First (Expressions (N));
475 E2 : constant Node_Id := Next (E1);
477 Find_Fat_Info (Etype (E1), Ftp, Pkg);
479 (N, Pkg, Attribute_Name (N),
481 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
482 Unchecked_Convert_To (Ftp, Relocate_Node (E2))));
483 end Expand_Fpt_Attribute_RR;
485 ----------------------------------
486 -- Expand_N_Attribute_Reference --
487 ----------------------------------
489 procedure Expand_N_Attribute_Reference (N : Node_Id) is
490 Loc : constant Source_Ptr := Sloc (N);
491 Typ : constant Entity_Id := Etype (N);
492 Btyp : constant Entity_Id := Base_Type (Typ);
493 Pref : constant Node_Id := Prefix (N);
494 Ptyp : constant Entity_Id := Etype (Pref);
495 Exprs : constant List_Id := Expressions (N);
496 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
498 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id);
499 -- Rewrites a stream attribute for Read, Write or Output with the
500 -- procedure call. Pname is the entity for the procedure to call.
502 ------------------------------
503 -- Rewrite_Stream_Proc_Call --
504 ------------------------------
506 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id) is
507 Item : constant Node_Id := Next (First (Exprs));
508 Formal : constant Entity_Id := Next_Formal (First_Formal (Pname));
509 Formal_Typ : constant Entity_Id := Etype (Formal);
510 Is_Written : constant Boolean := (Ekind (Formal) /= E_In_Parameter);
513 -- The expansion depends on Item, the second actual, which is
514 -- the object being streamed in or out.
516 -- If the item is a component of a packed array type, and
517 -- a conversion is needed on exit, we introduce a temporary to
518 -- hold the value, because otherwise the packed reference will
519 -- not be properly expanded.
521 if Nkind (Item) = N_Indexed_Component
522 and then Is_Packed (Base_Type (Etype (Prefix (Item))))
523 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
527 Temp : constant Entity_Id :=
528 Make_Defining_Identifier
529 (Loc, New_Internal_Name ('V'));
535 Make_Object_Declaration (Loc,
536 Defining_Identifier => Temp,
538 New_Occurrence_Of (Formal_Typ, Loc));
539 Set_Etype (Temp, Formal_Typ);
542 Make_Assignment_Statement (Loc,
543 Name => New_Copy_Tree (Item),
546 (Etype (Item), New_Occurrence_Of (Temp, Loc)));
548 Rewrite (Item, New_Occurrence_Of (Temp, Loc));
552 Make_Procedure_Call_Statement (Loc,
553 Name => New_Occurrence_Of (Pname, Loc),
554 Parameter_Associations => Exprs),
557 Rewrite (N, Make_Null_Statement (Loc));
562 -- For the class-wide dispatching cases, and for cases in which
563 -- the base type of the second argument matches the base type of
564 -- the corresponding formal parameter (that is to say the stream
565 -- operation is not inherited), we are all set, and can use the
566 -- argument unchanged.
568 -- For all other cases we do an unchecked conversion of the second
569 -- parameter to the type of the formal of the procedure we are
570 -- calling. This deals with the private type cases, and with going
571 -- to the root type as required in elementary type case.
573 if not Is_Class_Wide_Type (Entity (Pref))
574 and then not Is_Class_Wide_Type (Etype (Item))
575 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
578 Unchecked_Convert_To (Formal_Typ, Relocate_Node (Item)));
580 -- For untagged derived types set Assignment_OK, to prevent
581 -- copies from being created when the unchecked conversion
582 -- is expanded (which would happen in Remove_Side_Effects
583 -- if Expand_N_Unchecked_Conversion were allowed to call
584 -- Force_Evaluation). The copy could violate Ada semantics
585 -- in cases such as an actual that is an out parameter.
586 -- Note that this approach is also used in exp_ch7 for calls
587 -- to controlled type operations to prevent problems with
588 -- actuals wrapped in unchecked conversions.
590 if Is_Untagged_Derivation (Etype (Expression (Item))) then
591 Set_Assignment_OK (Item);
595 -- And now rewrite the call
598 Make_Procedure_Call_Statement (Loc,
599 Name => New_Occurrence_Of (Pname, Loc),
600 Parameter_Associations => Exprs));
603 end Rewrite_Stream_Proc_Call;
605 -- Start of processing for Expand_N_Attribute_Reference
608 -- Do required validity checking, if enabled. Do not apply check to
609 -- output parameters of an Asm instruction, since the value of this
610 -- is not set till after the attribute has been elaborated, and do
611 -- not apply the check to the arguments of a 'Read or 'Input attribute
612 -- reference since the scalar argument is an OUT scalar.
614 if Validity_Checks_On and then Validity_Check_Operands
615 and then Id /= Attribute_Asm_Output
616 and then Id /= Attribute_Read
617 and then Id /= Attribute_Input
622 Expr := First (Expressions (N));
623 while Present (Expr) loop
630 -- Ada 2005 (AI-318-02): If attribute prefix is a call to a build-in-
631 -- place function, then a temporary return object needs to be created
632 -- and access to it must be passed to the function. Currently we limit
633 -- such functions to those with inherently limited result subtypes, but
634 -- eventually we plan to expand the functions that are treated as
635 -- build-in-place to include other composite result types.
637 if Ada_Version >= Ada_05
638 and then Is_Build_In_Place_Function_Call (Pref)
640 Make_Build_In_Place_Call_In_Anonymous_Context (Pref);
643 -- If prefix is a protected type name, this is a reference to
644 -- the current instance of the type.
646 if Is_Protected_Self_Reference (Pref) then
647 Rewrite (Pref, Concurrent_Ref (Pref));
651 -- Remaining processing depends on specific attribute
659 when Attribute_Access |
660 Attribute_Unchecked_Access |
661 Attribute_Unrestricted_Access =>
663 Access_Cases : declare
664 Ref_Object : constant Node_Id := Get_Referenced_Object (Pref);
665 Btyp_DDT : Entity_Id;
667 function Enclosing_Object (N : Node_Id) return Node_Id;
668 -- If N denotes a compound name (selected component, indexed
669 -- component, or slice), returns the name of the outermost
670 -- such enclosing object. Otherwise returns N. If the object
671 -- is a renaming, then the renamed object is returned.
673 ----------------------
674 -- Enclosing_Object --
675 ----------------------
677 function Enclosing_Object (N : Node_Id) return Node_Id is
682 while Nkind_In (Obj_Name, N_Selected_Component,
686 Obj_Name := Prefix (Obj_Name);
689 return Get_Referenced_Object (Obj_Name);
690 end Enclosing_Object;
692 -- Local declarations
694 Enc_Object : constant Node_Id := Enclosing_Object (Ref_Object);
696 -- Start of processing for Access_Cases
699 Btyp_DDT := Designated_Type (Btyp);
701 -- Handle designated types that come from the limited view
703 if Ekind (Btyp_DDT) = E_Incomplete_Type
704 and then From_With_Type (Btyp_DDT)
705 and then Present (Non_Limited_View (Btyp_DDT))
707 Btyp_DDT := Non_Limited_View (Btyp_DDT);
709 elsif Is_Class_Wide_Type (Btyp_DDT)
710 and then Ekind (Etype (Btyp_DDT)) = E_Incomplete_Type
711 and then From_With_Type (Etype (Btyp_DDT))
712 and then Present (Non_Limited_View (Etype (Btyp_DDT)))
713 and then Present (Class_Wide_Type
714 (Non_Limited_View (Etype (Btyp_DDT))))
717 Class_Wide_Type (Non_Limited_View (Etype (Btyp_DDT)));
720 -- In order to improve the text of error messages, the designated
721 -- type of access-to-subprogram itypes is set by the semantics as
722 -- the associated subprogram entity (see sem_attr). Now we replace
723 -- such node with the proper E_Subprogram_Type itype.
725 if Id = Attribute_Unrestricted_Access
726 and then Is_Subprogram (Directly_Designated_Type (Typ))
728 -- The following conditions ensure that this special management
729 -- is done only for "Address!(Prim'Unrestricted_Access)" nodes.
730 -- At this stage other cases in which the designated type is
731 -- still a subprogram (instead of an E_Subprogram_Type) are
732 -- wrong because the semantics must have overridden the type of
733 -- the node with the type imposed by the context.
735 if Nkind (Parent (N)) = N_Unchecked_Type_Conversion
736 and then Etype (Parent (N)) = RTE (RE_Prim_Ptr)
738 Set_Etype (N, RTE (RE_Prim_Ptr));
742 Subp : constant Entity_Id :=
743 Directly_Designated_Type (Typ);
745 Extra : Entity_Id := Empty;
746 New_Formal : Entity_Id;
747 Old_Formal : Entity_Id := First_Formal (Subp);
748 Subp_Typ : Entity_Id;
751 Subp_Typ := Create_Itype (E_Subprogram_Type, N);
752 Set_Etype (Subp_Typ, Etype (Subp));
753 Set_Returns_By_Ref (Subp_Typ, Returns_By_Ref (Subp));
755 if Present (Old_Formal) then
756 New_Formal := New_Copy (Old_Formal);
757 Set_First_Entity (Subp_Typ, New_Formal);
760 Set_Scope (New_Formal, Subp_Typ);
761 Etyp := Etype (New_Formal);
763 -- Handle itypes. There is no need to duplicate
764 -- here the itypes associated with record types
765 -- (i.e the implicit full view of private types).
768 and then Ekind (Base_Type (Etyp)) /= E_Record_Type
770 Extra := New_Copy (Etyp);
771 Set_Parent (Extra, New_Formal);
772 Set_Etype (New_Formal, Extra);
773 Set_Scope (Extra, Subp_Typ);
777 Next_Formal (Old_Formal);
778 exit when No (Old_Formal);
780 Set_Next_Entity (New_Formal,
781 New_Copy (Old_Formal));
782 Next_Entity (New_Formal);
785 Set_Next_Entity (New_Formal, Empty);
786 Set_Last_Entity (Subp_Typ, Extra);
789 -- Now that the explicit formals have been duplicated,
790 -- any extra formals needed by the subprogram must be
793 if Present (Extra) then
794 Set_Extra_Formal (Extra, Empty);
797 Create_Extra_Formals (Subp_Typ);
798 Set_Directly_Designated_Type (Typ, Subp_Typ);
803 if Is_Access_Protected_Subprogram_Type (Btyp) then
804 Expand_Access_To_Protected_Op (N, Pref, Typ);
806 -- If prefix is a type name, this is a reference to the current
807 -- instance of the type, within its initialization procedure.
809 elsif Is_Entity_Name (Pref)
810 and then Is_Type (Entity (Pref))
817 -- If the current instance name denotes a task type, then
818 -- the access attribute is rewritten to be the name of the
819 -- "_task" parameter associated with the task type's task
820 -- procedure. An unchecked conversion is applied to ensure
821 -- a type match in cases of expander-generated calls (e.g.
824 if Is_Task_Type (Entity (Pref)) then
826 First_Entity (Get_Task_Body_Procedure (Entity (Pref)));
827 while Present (Formal) loop
828 exit when Chars (Formal) = Name_uTask;
829 Next_Entity (Formal);
832 pragma Assert (Present (Formal));
835 Unchecked_Convert_To (Typ,
836 New_Occurrence_Of (Formal, Loc)));
839 -- The expression must appear in a default expression,
840 -- (which in the initialization procedure is the
841 -- right-hand side of an assignment), and not in a
842 -- discriminant constraint.
846 while Present (Par) loop
847 exit when Nkind (Par) = N_Assignment_Statement;
849 if Nkind (Par) = N_Component_Declaration then
856 if Present (Par) then
858 Make_Attribute_Reference (Loc,
859 Prefix => Make_Identifier (Loc, Name_uInit),
860 Attribute_Name => Attribute_Name (N)));
862 Analyze_And_Resolve (N, Typ);
867 -- If the prefix of an Access attribute is a dereference of an
868 -- access parameter (or a renaming of such a dereference, or a
869 -- subcomponent of such a dereference) and the context is a
870 -- general access type (but not an anonymous access type), then
871 -- apply an accessibility check to the access parameter. We used
872 -- to rewrite the access parameter as a type conversion, but that
873 -- could only be done if the immediate prefix of the Access
874 -- attribute was the dereference, and didn't handle cases where
875 -- the attribute is applied to a subcomponent of the dereference,
876 -- since there's generally no available, appropriate access type
877 -- to convert to in that case. The attribute is passed as the
878 -- point to insert the check, because the access parameter may
879 -- come from a renaming, possibly in a different scope, and the
880 -- check must be associated with the attribute itself.
882 elsif Id = Attribute_Access
883 and then Nkind (Enc_Object) = N_Explicit_Dereference
884 and then Is_Entity_Name (Prefix (Enc_Object))
885 and then Ekind (Btyp) = E_General_Access_Type
886 and then Ekind (Entity (Prefix (Enc_Object))) in Formal_Kind
887 and then Ekind (Etype (Entity (Prefix (Enc_Object))))
888 = E_Anonymous_Access_Type
889 and then Present (Extra_Accessibility
890 (Entity (Prefix (Enc_Object))))
892 Apply_Accessibility_Check (Prefix (Enc_Object), Typ, N);
894 -- Ada 2005 (AI-251): If the designated type is an interface we
895 -- add an implicit conversion to force the displacement of the
896 -- pointer to reference the secondary dispatch table.
898 elsif Is_Interface (Btyp_DDT)
899 and then (Comes_From_Source (N)
900 or else Comes_From_Source (Ref_Object)
901 or else (Nkind (Ref_Object) in N_Has_Chars
902 and then Chars (Ref_Object) = Name_uInit))
904 if Nkind (Ref_Object) /= N_Explicit_Dereference then
906 -- No implicit conversion required if types match
908 if Btyp_DDT /= Etype (Ref_Object) then
910 Convert_To (Btyp_DDT,
911 New_Copy_Tree (Prefix (N))));
913 Analyze_And_Resolve (Prefix (N), Btyp_DDT);
916 -- When the object is an explicit dereference, convert the
917 -- dereference's prefix.
921 Obj_DDT : constant Entity_Id :=
923 (Directly_Designated_Type
924 (Etype (Prefix (Ref_Object))));
926 -- No implicit conversion required if designated types
929 if Obj_DDT /= Btyp_DDT
930 and then not (Is_Class_Wide_Type (Obj_DDT)
931 and then Etype (Obj_DDT) = Btyp_DDT)
935 New_Copy_Tree (Prefix (Ref_Object))));
936 Analyze_And_Resolve (N, Typ);
947 -- Transforms 'Adjacent into a call to the floating-point attribute
948 -- function Adjacent in Fat_xxx (where xxx is the root type)
950 when Attribute_Adjacent =>
951 Expand_Fpt_Attribute_RR (N);
957 when Attribute_Address => Address : declare
958 Task_Proc : Entity_Id;
961 -- If the prefix is a task or a task type, the useful address is that
962 -- of the procedure for the task body, i.e. the actual program unit.
963 -- We replace the original entity with that of the procedure.
965 if Is_Entity_Name (Pref)
966 and then Is_Task_Type (Entity (Pref))
968 Task_Proc := Next_Entity (Root_Type (Ptyp));
970 while Present (Task_Proc) loop
971 exit when Ekind (Task_Proc) = E_Procedure
972 and then Etype (First_Formal (Task_Proc)) =
973 Corresponding_Record_Type (Ptyp);
974 Next_Entity (Task_Proc);
977 if Present (Task_Proc) then
978 Set_Entity (Pref, Task_Proc);
979 Set_Etype (Pref, Etype (Task_Proc));
982 -- Similarly, the address of a protected operation is the address
983 -- of the corresponding protected body, regardless of the protected
984 -- object from which it is selected.
986 elsif Nkind (Pref) = N_Selected_Component
987 and then Is_Subprogram (Entity (Selector_Name (Pref)))
988 and then Is_Protected_Type (Scope (Entity (Selector_Name (Pref))))
992 External_Subprogram (Entity (Selector_Name (Pref))), Loc));
994 elsif Nkind (Pref) = N_Explicit_Dereference
995 and then Ekind (Ptyp) = E_Subprogram_Type
996 and then Convention (Ptyp) = Convention_Protected
998 -- The prefix is be a dereference of an access_to_protected_
999 -- subprogram. The desired address is the second component of
1000 -- the record that represents the access.
1003 Addr : constant Entity_Id := Etype (N);
1004 Ptr : constant Node_Id := Prefix (Pref);
1005 T : constant Entity_Id :=
1006 Equivalent_Type (Base_Type (Etype (Ptr)));
1010 Unchecked_Convert_To (Addr,
1011 Make_Selected_Component (Loc,
1012 Prefix => Unchecked_Convert_To (T, Ptr),
1013 Selector_Name => New_Occurrence_Of (
1014 Next_Entity (First_Entity (T)), Loc))));
1016 Analyze_And_Resolve (N, Addr);
1019 -- Ada 2005 (AI-251): Class-wide interface objects are always
1020 -- "displaced" to reference the tag associated with the interface
1021 -- type. In order to obtain the real address of such objects we
1022 -- generate a call to a run-time subprogram that returns the base
1023 -- address of the object.
1025 -- This processing is not needed in the VM case, where dispatching
1026 -- issues are taken care of by the virtual machine.
1028 elsif Is_Class_Wide_Type (Ptyp)
1029 and then Is_Interface (Ptyp)
1030 and then VM_Target = No_VM
1031 and then not (Nkind (Pref) in N_Has_Entity
1032 and then Is_Subprogram (Entity (Pref)))
1035 Make_Function_Call (Loc,
1036 Name => New_Reference_To (RTE (RE_Base_Address), Loc),
1037 Parameter_Associations => New_List (
1038 Relocate_Node (N))));
1043 -- Deal with packed array reference, other cases are handled by
1046 if Involves_Packed_Array_Reference (Pref) then
1047 Expand_Packed_Address_Reference (N);
1055 when Attribute_Alignment => Alignment : declare
1059 -- For class-wide types, X'Class'Alignment is transformed into a
1060 -- direct reference to the Alignment of the class type, so that the
1061 -- back end does not have to deal with the X'Class'Alignment
1064 if Is_Entity_Name (Pref)
1065 and then Is_Class_Wide_Type (Entity (Pref))
1067 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
1070 -- For x'Alignment applied to an object of a class wide type,
1071 -- transform X'Alignment into a call to the predefined primitive
1072 -- operation _Alignment applied to X.
1074 elsif Is_Class_Wide_Type (Ptyp) then
1076 -- No need to do anything else compiling under restriction
1077 -- No_Dispatching_Calls. During the semantic analysis we
1078 -- already notified such violation.
1080 if Restriction_Active (No_Dispatching_Calls) then
1085 Make_Function_Call (Loc,
1086 Name => New_Reference_To
1087 (Find_Prim_Op (Ptyp, Name_uAlignment), Loc),
1088 Parameter_Associations => New_List (Pref));
1090 if Typ /= Standard_Integer then
1092 -- The context is a specific integer type with which the
1093 -- original attribute was compatible. The function has a
1094 -- specific type as well, so to preserve the compatibility
1095 -- we must convert explicitly.
1097 New_Node := Convert_To (Typ, New_Node);
1100 Rewrite (N, New_Node);
1101 Analyze_And_Resolve (N, Typ);
1104 -- For all other cases, we just have to deal with the case of
1105 -- the fact that the result can be universal.
1108 Apply_Universal_Integer_Attribute_Checks (N);
1116 when Attribute_AST_Entry => AST_Entry : declare
1121 Entry_Ref : Node_Id;
1122 -- The reference to the entry or entry family
1125 -- The index expression for an entry family reference, or
1126 -- the Empty if Entry_Ref references a simple entry.
1129 if Nkind (Pref) = N_Indexed_Component then
1130 Entry_Ref := Prefix (Pref);
1131 Index := First (Expressions (Pref));
1137 -- Get expression for Task_Id and the entry entity
1139 if Nkind (Entry_Ref) = N_Selected_Component then
1141 Make_Attribute_Reference (Loc,
1142 Attribute_Name => Name_Identity,
1143 Prefix => Prefix (Entry_Ref));
1145 Ttyp := Etype (Prefix (Entry_Ref));
1146 Eent := Entity (Selector_Name (Entry_Ref));
1150 Make_Function_Call (Loc,
1151 Name => New_Occurrence_Of (RTE (RE_Current_Task), Loc));
1153 Eent := Entity (Entry_Ref);
1155 -- We have to find the enclosing task to get the task type
1156 -- There must be one, since we already validated this earlier
1158 Ttyp := Current_Scope;
1159 while not Is_Task_Type (Ttyp) loop
1160 Ttyp := Scope (Ttyp);
1164 -- Now rewrite the attribute with a call to Create_AST_Handler
1167 Make_Function_Call (Loc,
1168 Name => New_Occurrence_Of (RTE (RE_Create_AST_Handler), Loc),
1169 Parameter_Associations => New_List (
1171 Entry_Index_Expression (Loc, Eent, Index, Ttyp))));
1173 Analyze_And_Resolve (N, RTE (RE_AST_Handler));
1180 -- We compute this if a component clause was present, otherwise we leave
1181 -- the computation up to the back end, since we don't know what layout
1184 -- Note that the attribute can apply to a naked record component
1185 -- in generated code (i.e. the prefix is an identifier that
1186 -- references the component or discriminant entity).
1188 when Attribute_Bit_Position => Bit_Position :
1193 if Nkind (Pref) = N_Identifier then
1194 CE := Entity (Pref);
1196 CE := Entity (Selector_Name (Pref));
1199 if Known_Static_Component_Bit_Offset (CE) then
1201 Make_Integer_Literal (Loc,
1202 Intval => Component_Bit_Offset (CE)));
1203 Analyze_And_Resolve (N, Typ);
1206 Apply_Universal_Integer_Attribute_Checks (N);
1214 -- A reference to P'Body_Version or P'Version is expanded to
1217 -- pragma Import (C, Vnn, "uuuuT";
1219 -- Get_Version_String (Vnn)
1221 -- where uuuu is the unit name (dots replaced by double underscore)
1222 -- and T is B for the cases of Body_Version, or Version applied to a
1223 -- subprogram acting as its own spec, and S for Version applied to a
1224 -- subprogram spec or package. This sequence of code references the
1225 -- the unsigned constant created in the main program by the binder.
1227 -- A special exception occurs for Standard, where the string
1228 -- returned is a copy of the library string in gnatvsn.ads.
1230 when Attribute_Body_Version | Attribute_Version => Version : declare
1231 E : constant Entity_Id :=
1232 Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
1237 -- If not library unit, get to containing library unit
1239 Pent := Entity (Pref);
1240 while Pent /= Standard_Standard
1241 and then Scope (Pent) /= Standard_Standard
1242 and then not Is_Child_Unit (Pent)
1244 Pent := Scope (Pent);
1247 -- Special case Standard and Standard.ASCII
1249 if Pent = Standard_Standard or else Pent = Standard_ASCII then
1251 Make_String_Literal (Loc,
1252 Strval => Verbose_Library_Version));
1257 -- Build required string constant
1259 Get_Name_String (Get_Unit_Name (Pent));
1262 for J in 1 .. Name_Len - 2 loop
1263 if Name_Buffer (J) = '.' then
1264 Store_String_Chars ("__");
1266 Store_String_Char (Get_Char_Code (Name_Buffer (J)));
1270 -- Case of subprogram acting as its own spec, always use body
1272 if Nkind (Declaration_Node (Pent)) in N_Subprogram_Specification
1273 and then Nkind (Parent (Declaration_Node (Pent))) =
1275 and then Acts_As_Spec (Parent (Declaration_Node (Pent)))
1277 Store_String_Chars ("B");
1279 -- Case of no body present, always use spec
1281 elsif not Unit_Requires_Body (Pent) then
1282 Store_String_Chars ("S");
1284 -- Otherwise use B for Body_Version, S for spec
1286 elsif Id = Attribute_Body_Version then
1287 Store_String_Chars ("B");
1289 Store_String_Chars ("S");
1293 Lib.Version_Referenced (S);
1295 -- Insert the object declaration
1297 Insert_Actions (N, New_List (
1298 Make_Object_Declaration (Loc,
1299 Defining_Identifier => E,
1300 Object_Definition =>
1301 New_Occurrence_Of (RTE (RE_Unsigned), Loc))));
1303 -- Set entity as imported with correct external name
1305 Set_Is_Imported (E);
1306 Set_Interface_Name (E, Make_String_Literal (Loc, S));
1308 -- Set entity as internal to ensure proper Sprint output of its
1309 -- implicit importation.
1311 Set_Is_Internal (E);
1313 -- And now rewrite original reference
1316 Make_Function_Call (Loc,
1317 Name => New_Reference_To (RTE (RE_Get_Version_String), Loc),
1318 Parameter_Associations => New_List (
1319 New_Occurrence_Of (E, Loc))));
1322 Analyze_And_Resolve (N, RTE (RE_Version_String));
1329 -- Transforms 'Ceiling into a call to the floating-point attribute
1330 -- function Ceiling in Fat_xxx (where xxx is the root type)
1332 when Attribute_Ceiling =>
1333 Expand_Fpt_Attribute_R (N);
1339 -- Transforms 'Callable attribute into a call to the Callable function
1341 when Attribute_Callable => Callable :
1343 -- We have an object of a task interface class-wide type as a prefix
1344 -- to Callable. Generate:
1346 -- callable (Task_Id (Pref._disp_get_task_id));
1348 if Ada_Version >= Ada_05
1349 and then Ekind (Ptyp) = E_Class_Wide_Type
1350 and then Is_Interface (Ptyp)
1351 and then Is_Task_Interface (Ptyp)
1354 Make_Function_Call (Loc,
1356 New_Reference_To (RTE (RE_Callable), Loc),
1357 Parameter_Associations => New_List (
1358 Make_Unchecked_Type_Conversion (Loc,
1360 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
1362 Make_Selected_Component (Loc,
1364 New_Copy_Tree (Pref),
1366 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
1370 Build_Call_With_Task (Pref, RTE (RE_Callable)));
1373 Analyze_And_Resolve (N, Standard_Boolean);
1380 -- Transforms 'Caller attribute into a call to either the
1381 -- Task_Entry_Caller or the Protected_Entry_Caller function.
1383 when Attribute_Caller => Caller : declare
1384 Id_Kind : constant Entity_Id := RTE (RO_AT_Task_Id);
1385 Ent : constant Entity_Id := Entity (Pref);
1386 Conctype : constant Entity_Id := Scope (Ent);
1387 Nest_Depth : Integer := 0;
1394 if Is_Protected_Type (Conctype) then
1395 case Corresponding_Runtime_Package (Conctype) is
1396 when System_Tasking_Protected_Objects_Entries =>
1399 (RTE (RE_Protected_Entry_Caller), Loc);
1401 when System_Tasking_Protected_Objects_Single_Entry =>
1404 (RTE (RE_Protected_Single_Entry_Caller), Loc);
1407 raise Program_Error;
1411 Unchecked_Convert_To (Id_Kind,
1412 Make_Function_Call (Loc,
1414 Parameter_Associations => New_List (
1416 (Find_Protection_Object (Current_Scope), Loc)))));
1421 -- Determine the nesting depth of the E'Caller attribute, that
1422 -- is, how many accept statements are nested within the accept
1423 -- statement for E at the point of E'Caller. The runtime uses
1424 -- this depth to find the specified entry call.
1426 for J in reverse 0 .. Scope_Stack.Last loop
1427 S := Scope_Stack.Table (J).Entity;
1429 -- We should not reach the scope of the entry, as it should
1430 -- already have been checked in Sem_Attr that this attribute
1431 -- reference is within a matching accept statement.
1433 pragma Assert (S /= Conctype);
1438 elsif Is_Entry (S) then
1439 Nest_Depth := Nest_Depth + 1;
1444 Unchecked_Convert_To (Id_Kind,
1445 Make_Function_Call (Loc,
1447 New_Reference_To (RTE (RE_Task_Entry_Caller), Loc),
1448 Parameter_Associations => New_List (
1449 Make_Integer_Literal (Loc,
1450 Intval => Int (Nest_Depth))))));
1453 Analyze_And_Resolve (N, Id_Kind);
1460 -- Transforms 'Compose into a call to the floating-point attribute
1461 -- function Compose in Fat_xxx (where xxx is the root type)
1463 -- Note: we strictly should have special code here to deal with the
1464 -- case of absurdly negative arguments (less than Integer'First)
1465 -- which will return a (signed) zero value, but it hardly seems
1466 -- worth the effort. Absurdly large positive arguments will raise
1467 -- constraint error which is fine.
1469 when Attribute_Compose =>
1470 Expand_Fpt_Attribute_RI (N);
1476 when Attribute_Constrained => Constrained : declare
1477 Formal_Ent : constant Entity_Id := Param_Entity (Pref);
1479 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean;
1480 -- Ada 2005 (AI-363): Returns True if the object name Obj denotes a
1481 -- view of an aliased object whose subtype is constrained.
1483 ---------------------------------
1484 -- Is_Constrained_Aliased_View --
1485 ---------------------------------
1487 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean is
1491 if Is_Entity_Name (Obj) then
1494 if Present (Renamed_Object (E)) then
1495 return Is_Constrained_Aliased_View (Renamed_Object (E));
1497 return Is_Aliased (E) and then Is_Constrained (Etype (E));
1501 return Is_Aliased_View (Obj)
1503 (Is_Constrained (Etype (Obj))
1504 or else (Nkind (Obj) = N_Explicit_Dereference
1506 not Has_Constrained_Partial_View
1507 (Base_Type (Etype (Obj)))));
1509 end Is_Constrained_Aliased_View;
1511 -- Start of processing for Constrained
1514 -- Reference to a parameter where the value is passed as an extra
1515 -- actual, corresponding to the extra formal referenced by the
1516 -- Extra_Constrained field of the corresponding formal. If this
1517 -- is an entry in-parameter, it is replaced by a constant renaming
1518 -- for which Extra_Constrained is never created.
1520 if Present (Formal_Ent)
1521 and then Ekind (Formal_Ent) /= E_Constant
1522 and then Present (Extra_Constrained (Formal_Ent))
1526 (Extra_Constrained (Formal_Ent), Sloc (N)));
1528 -- For variables with a Extra_Constrained field, we use the
1529 -- corresponding entity.
1531 elsif Nkind (Pref) = N_Identifier
1532 and then Ekind (Entity (Pref)) = E_Variable
1533 and then Present (Extra_Constrained (Entity (Pref)))
1537 (Extra_Constrained (Entity (Pref)), Sloc (N)));
1539 -- For all other entity names, we can tell at compile time
1541 elsif Is_Entity_Name (Pref) then
1543 Ent : constant Entity_Id := Entity (Pref);
1547 -- (RM J.4) obsolescent cases
1549 if Is_Type (Ent) then
1553 if Is_Private_Type (Ent) then
1554 Res := not Has_Discriminants (Ent)
1555 or else Is_Constrained (Ent);
1557 -- It not a private type, must be a generic actual type
1558 -- that corresponded to a private type. We know that this
1559 -- correspondence holds, since otherwise the reference
1560 -- within the generic template would have been illegal.
1563 if Is_Composite_Type (Underlying_Type (Ent)) then
1564 Res := Is_Constrained (Ent);
1570 -- If the prefix is not a variable or is aliased, then
1571 -- definitely true; if it's a formal parameter without an
1572 -- associated extra formal, then treat it as constrained.
1574 -- Ada 2005 (AI-363): An aliased prefix must be known to be
1575 -- constrained in order to set the attribute to True.
1577 elsif not Is_Variable (Pref)
1578 or else Present (Formal_Ent)
1579 or else (Ada_Version < Ada_05
1580 and then Is_Aliased_View (Pref))
1581 or else (Ada_Version >= Ada_05
1582 and then Is_Constrained_Aliased_View (Pref))
1586 -- Variable case, look at type to see if it is constrained.
1587 -- Note that the one case where this is not accurate (the
1588 -- procedure formal case), has been handled above.
1590 -- We use the Underlying_Type here (and below) in case the
1591 -- type is private without discriminants, but the full type
1592 -- has discriminants. This case is illegal, but we generate it
1593 -- internally for passing to the Extra_Constrained parameter.
1596 Res := Is_Constrained (Underlying_Type (Etype (Ent)));
1600 New_Reference_To (Boolean_Literals (Res), Loc));
1603 -- Prefix is not an entity name. These are also cases where we can
1604 -- always tell at compile time by looking at the form and type of the
1605 -- prefix. If an explicit dereference of an object with constrained
1606 -- partial view, this is unconstrained (Ada 2005 AI-363).
1612 not Is_Variable (Pref)
1614 (Nkind (Pref) = N_Explicit_Dereference
1616 not Has_Constrained_Partial_View (Base_Type (Ptyp)))
1617 or else Is_Constrained (Underlying_Type (Ptyp))),
1621 Analyze_And_Resolve (N, Standard_Boolean);
1628 -- Transforms 'Copy_Sign into a call to the floating-point attribute
1629 -- function Copy_Sign in Fat_xxx (where xxx is the root type)
1631 when Attribute_Copy_Sign =>
1632 Expand_Fpt_Attribute_RR (N);
1638 -- Transforms 'Count attribute into a call to the Count function
1640 when Attribute_Count => Count : declare
1642 Conctyp : Entity_Id;
1644 Entry_Id : Entity_Id;
1649 -- If the prefix is a member of an entry family, retrieve both
1650 -- entry name and index. For a simple entry there is no index.
1652 if Nkind (Pref) = N_Indexed_Component then
1653 Entnam := Prefix (Pref);
1654 Index := First (Expressions (Pref));
1660 Entry_Id := Entity (Entnam);
1662 -- Find the concurrent type in which this attribute is referenced
1663 -- (there had better be one).
1665 Conctyp := Current_Scope;
1666 while not Is_Concurrent_Type (Conctyp) loop
1667 Conctyp := Scope (Conctyp);
1672 if Is_Protected_Type (Conctyp) then
1673 case Corresponding_Runtime_Package (Conctyp) is
1674 when System_Tasking_Protected_Objects_Entries =>
1675 Name := New_Reference_To (RTE (RE_Protected_Count), Loc);
1678 Make_Function_Call (Loc,
1680 Parameter_Associations => New_List (
1682 (Find_Protection_Object (Current_Scope), Loc),
1683 Entry_Index_Expression
1684 (Loc, Entry_Id, Index, Scope (Entry_Id))));
1686 when System_Tasking_Protected_Objects_Single_Entry =>
1688 New_Reference_To (RTE (RE_Protected_Count_Entry), Loc);
1691 Make_Function_Call (Loc,
1693 Parameter_Associations => New_List (
1695 (Find_Protection_Object (Current_Scope), Loc)));
1698 raise Program_Error;
1705 Make_Function_Call (Loc,
1706 Name => New_Reference_To (RTE (RE_Task_Count), Loc),
1707 Parameter_Associations => New_List (
1708 Entry_Index_Expression (Loc,
1709 Entry_Id, Index, Scope (Entry_Id))));
1712 -- The call returns type Natural but the context is universal integer
1713 -- so any integer type is allowed. The attribute was already resolved
1714 -- so its Etype is the required result type. If the base type of the
1715 -- context type is other than Standard.Integer we put in a conversion
1716 -- to the required type. This can be a normal typed conversion since
1717 -- both input and output types of the conversion are integer types
1719 if Base_Type (Typ) /= Base_Type (Standard_Integer) then
1720 Rewrite (N, Convert_To (Typ, Call));
1725 Analyze_And_Resolve (N, Typ);
1732 -- This processing is shared by Elab_Spec
1734 -- What we do is to insert the following declarations
1737 -- pragma Import (C, enn, "name___elabb/s");
1739 -- and then the Elab_Body/Spec attribute is replaced by a reference
1740 -- to this defining identifier.
1742 when Attribute_Elab_Body |
1743 Attribute_Elab_Spec =>
1746 Ent : constant Entity_Id :=
1747 Make_Defining_Identifier (Loc,
1748 New_Internal_Name ('E'));
1752 procedure Make_Elab_String (Nod : Node_Id);
1753 -- Given Nod, an identifier, or a selected component, put the
1754 -- image into the current string literal, with double underline
1755 -- between components.
1757 ----------------------
1758 -- Make_Elab_String --
1759 ----------------------
1761 procedure Make_Elab_String (Nod : Node_Id) is
1763 if Nkind (Nod) = N_Selected_Component then
1764 Make_Elab_String (Prefix (Nod));
1768 Store_String_Char ('$');
1770 Store_String_Char ('.');
1772 Store_String_Char ('_');
1773 Store_String_Char ('_');
1776 Get_Name_String (Chars (Selector_Name (Nod)));
1779 pragma Assert (Nkind (Nod) = N_Identifier);
1780 Get_Name_String (Chars (Nod));
1783 Store_String_Chars (Name_Buffer (1 .. Name_Len));
1784 end Make_Elab_String;
1786 -- Start of processing for Elab_Body/Elab_Spec
1789 -- First we need to prepare the string literal for the name of
1790 -- the elaboration routine to be referenced.
1793 Make_Elab_String (Pref);
1795 if VM_Target = No_VM then
1796 Store_String_Chars ("___elab");
1797 Lang := Make_Identifier (Loc, Name_C);
1799 Store_String_Chars ("._elab");
1800 Lang := Make_Identifier (Loc, Name_Ada);
1803 if Id = Attribute_Elab_Body then
1804 Store_String_Char ('b');
1806 Store_String_Char ('s');
1811 Insert_Actions (N, New_List (
1812 Make_Subprogram_Declaration (Loc,
1814 Make_Procedure_Specification (Loc,
1815 Defining_Unit_Name => Ent)),
1818 Chars => Name_Import,
1819 Pragma_Argument_Associations => New_List (
1820 Make_Pragma_Argument_Association (Loc,
1821 Expression => Lang),
1823 Make_Pragma_Argument_Association (Loc,
1825 Make_Identifier (Loc, Chars (Ent))),
1827 Make_Pragma_Argument_Association (Loc,
1829 Make_String_Literal (Loc, Str))))));
1831 Set_Entity (N, Ent);
1832 Rewrite (N, New_Occurrence_Of (Ent, Loc));
1839 -- Elaborated is always True for preelaborated units, predefined units,
1840 -- pure units and units which have Elaborate_Body pragmas. These units
1841 -- have no elaboration entity.
1843 -- Note: The Elaborated attribute is never passed to the back end
1845 when Attribute_Elaborated => Elaborated : declare
1846 Ent : constant Entity_Id := Entity (Pref);
1849 if Present (Elaboration_Entity (Ent)) then
1851 New_Occurrence_Of (Elaboration_Entity (Ent), Loc));
1853 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
1861 when Attribute_Enum_Rep => Enum_Rep :
1863 -- X'Enum_Rep (Y) expands to
1867 -- This is simply a direct conversion from the enumeration type to
1868 -- the target integer type, which is treated by the back end as a
1869 -- normal integer conversion, treating the enumeration type as an
1870 -- integer, which is exactly what we want! We set Conversion_OK to
1871 -- make sure that the analyzer does not complain about what otherwise
1872 -- might be an illegal conversion.
1874 if Is_Non_Empty_List (Exprs) then
1876 OK_Convert_To (Typ, Relocate_Node (First (Exprs))));
1878 -- X'Enum_Rep where X is an enumeration literal is replaced by
1879 -- the literal value.
1881 elsif Ekind (Entity (Pref)) = E_Enumeration_Literal then
1883 Make_Integer_Literal (Loc, Enumeration_Rep (Entity (Pref))));
1885 -- If this is a renaming of a literal, recover the representation
1888 elsif Ekind (Entity (Pref)) = E_Constant
1889 and then Present (Renamed_Object (Entity (Pref)))
1891 Ekind (Entity (Renamed_Object (Entity (Pref))))
1892 = E_Enumeration_Literal
1895 Make_Integer_Literal (Loc,
1896 Enumeration_Rep (Entity (Renamed_Object (Entity (Pref))))));
1898 -- X'Enum_Rep where X is an object does a direct unchecked conversion
1899 -- of the object value, as described for the type case above.
1903 OK_Convert_To (Typ, Relocate_Node (Pref)));
1907 Analyze_And_Resolve (N, Typ);
1914 when Attribute_Enum_Val => Enum_Val : declare
1916 Btyp : constant Entity_Id := Base_Type (Ptyp);
1919 -- X'Enum_Val (Y) expands to
1921 -- [constraint_error when _rep_to_pos (Y, False) = -1, msg]
1924 Expr := Unchecked_Convert_To (Ptyp, First (Exprs));
1927 Make_Raise_Constraint_Error (Loc,
1931 Make_Function_Call (Loc,
1933 New_Reference_To (TSS (Btyp, TSS_Rep_To_Pos), Loc),
1934 Parameter_Associations => New_List (
1935 Relocate_Node (Duplicate_Subexpr (Expr)),
1936 New_Occurrence_Of (Standard_False, Loc))),
1938 Right_Opnd => Make_Integer_Literal (Loc, -1)),
1939 Reason => CE_Range_Check_Failed));
1942 Analyze_And_Resolve (N, Ptyp);
1949 -- Transforms 'Exponent into a call to the floating-point attribute
1950 -- function Exponent in Fat_xxx (where xxx is the root type)
1952 when Attribute_Exponent =>
1953 Expand_Fpt_Attribute_R (N);
1959 -- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag)
1961 when Attribute_External_Tag => External_Tag :
1964 Make_Function_Call (Loc,
1965 Name => New_Reference_To (RTE (RE_External_Tag), Loc),
1966 Parameter_Associations => New_List (
1967 Make_Attribute_Reference (Loc,
1968 Attribute_Name => Name_Tag,
1969 Prefix => Prefix (N)))));
1971 Analyze_And_Resolve (N, Standard_String);
1978 when Attribute_First =>
1980 -- If the prefix type is a constrained packed array type which
1981 -- already has a Packed_Array_Type representation defined, then
1982 -- replace this attribute with a direct reference to 'First of the
1983 -- appropriate index subtype (since otherwise the back end will try
1984 -- to give us the value of 'First for this implementation type).
1986 if Is_Constrained_Packed_Array (Ptyp) then
1988 Make_Attribute_Reference (Loc,
1989 Attribute_Name => Name_First,
1990 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
1991 Analyze_And_Resolve (N, Typ);
1993 elsif Is_Access_Type (Ptyp) then
1994 Apply_Access_Check (N);
2001 -- Compute this if component clause was present, otherwise we leave the
2002 -- computation to be completed in the back-end, since we don't know what
2003 -- layout will be chosen.
2005 when Attribute_First_Bit => First_Bit : declare
2006 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2009 if Known_Static_Component_Bit_Offset (CE) then
2011 Make_Integer_Literal (Loc,
2012 Component_Bit_Offset (CE) mod System_Storage_Unit));
2014 Analyze_And_Resolve (N, Typ);
2017 Apply_Universal_Integer_Attribute_Checks (N);
2027 -- fixtype'Fixed_Value (integer-value)
2031 -- fixtype(integer-value)
2033 -- We do all the required analysis of the conversion here, because we do
2034 -- not want this to go through the fixed-point conversion circuits. Note
2035 -- that the back end always treats fixed-point as equivalent to the
2036 -- corresponding integer type anyway.
2038 when Attribute_Fixed_Value => Fixed_Value :
2041 Make_Type_Conversion (Loc,
2042 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2043 Expression => Relocate_Node (First (Exprs))));
2044 Set_Etype (N, Entity (Pref));
2047 -- Note: it might appear that a properly analyzed unchecked conversion
2048 -- would be just fine here, but that's not the case, since the full
2049 -- range checks performed by the following call are critical!
2051 Apply_Type_Conversion_Checks (N);
2058 -- Transforms 'Floor into a call to the floating-point attribute
2059 -- function Floor in Fat_xxx (where xxx is the root type)
2061 when Attribute_Floor =>
2062 Expand_Fpt_Attribute_R (N);
2068 -- For the fixed-point type Typ:
2074 -- Result_Type (System.Fore (Universal_Real (Type'First)),
2075 -- Universal_Real (Type'Last))
2077 -- Note that we know that the type is a non-static subtype, or Fore
2078 -- would have itself been computed dynamically in Eval_Attribute.
2080 when Attribute_Fore => Fore : begin
2083 Make_Function_Call (Loc,
2084 Name => New_Reference_To (RTE (RE_Fore), Loc),
2086 Parameter_Associations => New_List (
2087 Convert_To (Universal_Real,
2088 Make_Attribute_Reference (Loc,
2089 Prefix => New_Reference_To (Ptyp, Loc),
2090 Attribute_Name => Name_First)),
2092 Convert_To (Universal_Real,
2093 Make_Attribute_Reference (Loc,
2094 Prefix => New_Reference_To (Ptyp, Loc),
2095 Attribute_Name => Name_Last))))));
2097 Analyze_And_Resolve (N, Typ);
2104 -- Transforms 'Fraction into a call to the floating-point attribute
2105 -- function Fraction in Fat_xxx (where xxx is the root type)
2107 when Attribute_Fraction =>
2108 Expand_Fpt_Attribute_R (N);
2114 when Attribute_From_Any => From_Any : declare
2115 P_Type : constant Entity_Id := Etype (Pref);
2116 Decls : constant List_Id := New_List;
2119 Build_From_Any_Call (P_Type,
2120 Relocate_Node (First (Exprs)),
2122 Insert_Actions (N, Decls);
2123 Analyze_And_Resolve (N, P_Type);
2130 -- For an exception returns a reference to the exception data:
2131 -- Exception_Id!(Prefix'Reference)
2133 -- For a task it returns a reference to the _task_id component of
2134 -- corresponding record:
2136 -- taskV!(Prefix)._Task_Id, converted to the type Task_Id defined
2138 -- in Ada.Task_Identification
2140 when Attribute_Identity => Identity : declare
2141 Id_Kind : Entity_Id;
2144 if Ptyp = Standard_Exception_Type then
2145 Id_Kind := RTE (RE_Exception_Id);
2147 if Present (Renamed_Object (Entity (Pref))) then
2148 Set_Entity (Pref, Renamed_Object (Entity (Pref)));
2152 Unchecked_Convert_To (Id_Kind, Make_Reference (Loc, Pref)));
2154 Id_Kind := RTE (RO_AT_Task_Id);
2156 -- If the prefix is a task interface, the Task_Id is obtained
2157 -- dynamically through a dispatching call, as for other task
2158 -- attributes applied to interfaces.
2160 if Ada_Version >= Ada_05
2161 and then Ekind (Ptyp) = E_Class_Wide_Type
2162 and then Is_Interface (Ptyp)
2163 and then Is_Task_Interface (Ptyp)
2166 Unchecked_Convert_To (Id_Kind,
2167 Make_Selected_Component (Loc,
2169 New_Copy_Tree (Pref),
2171 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))));
2175 Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref)));
2179 Analyze_And_Resolve (N, Id_Kind);
2186 -- Image attribute is handled in separate unit Exp_Imgv
2188 when Attribute_Image =>
2189 Exp_Imgv.Expand_Image_Attribute (N);
2195 -- X'Img is expanded to typ'Image (X), where typ is the type of X
2197 when Attribute_Img => Img :
2200 Make_Attribute_Reference (Loc,
2201 Prefix => New_Reference_To (Ptyp, Loc),
2202 Attribute_Name => Name_Image,
2203 Expressions => New_List (Relocate_Node (Pref))));
2205 Analyze_And_Resolve (N, Standard_String);
2212 when Attribute_Input => Input : declare
2213 P_Type : constant Entity_Id := Entity (Pref);
2214 B_Type : constant Entity_Id := Base_Type (P_Type);
2215 U_Type : constant Entity_Id := Underlying_Type (P_Type);
2216 Strm : constant Node_Id := First (Exprs);
2224 Cntrl : Node_Id := Empty;
2225 -- Value for controlling argument in call. Always Empty except in
2226 -- the dispatching (class-wide type) case, where it is a reference
2227 -- to the dummy object initialized to the right internal tag.
2229 procedure Freeze_Stream_Subprogram (F : Entity_Id);
2230 -- The expansion of the attribute reference may generate a call to
2231 -- a user-defined stream subprogram that is frozen by the call. This
2232 -- can lead to access-before-elaboration problem if the reference
2233 -- appears in an object declaration and the subprogram body has not
2234 -- been seen. The freezing of the subprogram requires special code
2235 -- because it appears in an expanded context where expressions do
2236 -- not freeze their constituents.
2238 ------------------------------
2239 -- Freeze_Stream_Subprogram --
2240 ------------------------------
2242 procedure Freeze_Stream_Subprogram (F : Entity_Id) is
2243 Decl : constant Node_Id := Unit_Declaration_Node (F);
2247 -- If this is user-defined subprogram, the corresponding
2248 -- stream function appears as a renaming-as-body, and the
2249 -- user subprogram must be retrieved by tree traversal.
2252 and then Nkind (Decl) = N_Subprogram_Declaration
2253 and then Present (Corresponding_Body (Decl))
2255 Bod := Corresponding_Body (Decl);
2257 if Nkind (Unit_Declaration_Node (Bod)) =
2258 N_Subprogram_Renaming_Declaration
2260 Set_Is_Frozen (Entity (Name (Unit_Declaration_Node (Bod))));
2263 end Freeze_Stream_Subprogram;
2265 -- Start of processing for Input
2268 -- If no underlying type, we have an error that will be diagnosed
2269 -- elsewhere, so here we just completely ignore the expansion.
2275 -- If there is a TSS for Input, just call it
2277 Fname := Find_Stream_Subprogram (P_Type, TSS_Stream_Input);
2279 if Present (Fname) then
2283 -- If there is a Stream_Convert pragma, use it, we rewrite
2285 -- sourcetyp'Input (stream)
2289 -- sourcetyp (streamread (strmtyp'Input (stream)));
2291 -- where streamread is the given Read function that converts an
2292 -- argument of type strmtyp to type sourcetyp or a type from which
2293 -- it is derived (extra conversion required for the derived case).
2295 Prag := Get_Stream_Convert_Pragma (P_Type);
2297 if Present (Prag) then
2298 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
2299 Rfunc := Entity (Expression (Arg2));
2303 Make_Function_Call (Loc,
2304 Name => New_Occurrence_Of (Rfunc, Loc),
2305 Parameter_Associations => New_List (
2306 Make_Attribute_Reference (Loc,
2309 (Etype (First_Formal (Rfunc)), Loc),
2310 Attribute_Name => Name_Input,
2311 Expressions => Exprs)))));
2313 Analyze_And_Resolve (N, B_Type);
2318 elsif Is_Elementary_Type (U_Type) then
2320 -- A special case arises if we have a defined _Read routine,
2321 -- since in this case we are required to call this routine.
2323 if Present (TSS (Base_Type (U_Type), TSS_Stream_Read)) then
2324 Build_Record_Or_Elementary_Input_Function
2325 (Loc, U_Type, Decl, Fname);
2326 Insert_Action (N, Decl);
2328 -- For normal cases, we call the I_xxx routine directly
2331 Rewrite (N, Build_Elementary_Input_Call (N));
2332 Analyze_And_Resolve (N, P_Type);
2338 elsif Is_Array_Type (U_Type) then
2339 Build_Array_Input_Function (Loc, U_Type, Decl, Fname);
2340 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
2342 -- Dispatching case with class-wide type
2344 elsif Is_Class_Wide_Type (P_Type) then
2346 -- No need to do anything else compiling under restriction
2347 -- No_Dispatching_Calls. During the semantic analysis we
2348 -- already notified such violation.
2350 if Restriction_Active (No_Dispatching_Calls) then
2355 Rtyp : constant Entity_Id := Root_Type (P_Type);
2360 -- Read the internal tag (RM 13.13.2(34)) and use it to
2361 -- initialize a dummy tag object:
2363 -- Dnn : Ada.Tags.Tag
2364 -- := Descendant_Tag (String'Input (Strm), P_Type);
2366 -- This dummy object is used only to provide a controlling
2367 -- argument for the eventual _Input call. Descendant_Tag is
2368 -- called rather than Internal_Tag to ensure that we have a
2369 -- tag for a type that is descended from the prefix type and
2370 -- declared at the same accessibility level (the exception
2371 -- Tag_Error will be raised otherwise). The level check is
2372 -- required for Ada 2005 because tagged types can be
2373 -- extended in nested scopes (AI-344).
2376 Make_Defining_Identifier (Loc,
2377 Chars => New_Internal_Name ('D'));
2380 Make_Object_Declaration (Loc,
2381 Defining_Identifier => Dnn,
2382 Object_Definition =>
2383 New_Occurrence_Of (RTE (RE_Tag), Loc),
2385 Make_Function_Call (Loc,
2387 New_Occurrence_Of (RTE (RE_Descendant_Tag), Loc),
2388 Parameter_Associations => New_List (
2389 Make_Attribute_Reference (Loc,
2391 New_Occurrence_Of (Standard_String, Loc),
2392 Attribute_Name => Name_Input,
2393 Expressions => New_List (
2395 (Duplicate_Subexpr (Strm)))),
2396 Make_Attribute_Reference (Loc,
2397 Prefix => New_Reference_To (P_Type, Loc),
2398 Attribute_Name => Name_Tag))));
2400 Insert_Action (N, Decl);
2402 -- Now we need to get the entity for the call, and construct
2403 -- a function call node, where we preset a reference to Dnn
2404 -- as the controlling argument (doing an unchecked convert
2405 -- to the class-wide tagged type to make it look like a real
2408 Fname := Find_Prim_Op (Rtyp, TSS_Stream_Input);
2409 Cntrl := Unchecked_Convert_To (P_Type,
2410 New_Occurrence_Of (Dnn, Loc));
2411 Set_Etype (Cntrl, P_Type);
2412 Set_Parent (Cntrl, N);
2415 -- For tagged types, use the primitive Input function
2417 elsif Is_Tagged_Type (U_Type) then
2418 Fname := Find_Prim_Op (U_Type, TSS_Stream_Input);
2420 -- All other record type cases, including protected records. The
2421 -- latter only arise for expander generated code for handling
2422 -- shared passive partition access.
2426 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
2428 -- Ada 2005 (AI-216): Program_Error is raised executing default
2429 -- implementation of the Input attribute of an unchecked union
2430 -- type if the type lacks default discriminant values.
2432 if Is_Unchecked_Union (Base_Type (U_Type))
2433 and then No (Discriminant_Constraint (U_Type))
2436 Make_Raise_Program_Error (Loc,
2437 Reason => PE_Unchecked_Union_Restriction));
2442 Build_Record_Or_Elementary_Input_Function
2443 (Loc, Base_Type (U_Type), Decl, Fname);
2444 Insert_Action (N, Decl);
2446 if Nkind (Parent (N)) = N_Object_Declaration
2447 and then Is_Record_Type (U_Type)
2449 -- The stream function may contain calls to user-defined
2450 -- Read procedures for individual components.
2457 Comp := First_Component (U_Type);
2458 while Present (Comp) loop
2460 Find_Stream_Subprogram
2461 (Etype (Comp), TSS_Stream_Read);
2463 if Present (Func) then
2464 Freeze_Stream_Subprogram (Func);
2467 Next_Component (Comp);
2474 -- If we fall through, Fname is the function to be called. The result
2475 -- is obtained by calling the appropriate function, then converting
2476 -- the result. The conversion does a subtype check.
2479 Make_Function_Call (Loc,
2480 Name => New_Occurrence_Of (Fname, Loc),
2481 Parameter_Associations => New_List (
2482 Relocate_Node (Strm)));
2484 Set_Controlling_Argument (Call, Cntrl);
2485 Rewrite (N, Unchecked_Convert_To (P_Type, Call));
2486 Analyze_And_Resolve (N, P_Type);
2488 if Nkind (Parent (N)) = N_Object_Declaration then
2489 Freeze_Stream_Subprogram (Fname);
2499 -- inttype'Fixed_Value (fixed-value)
2503 -- inttype(integer-value))
2505 -- we do all the required analysis of the conversion here, because we do
2506 -- not want this to go through the fixed-point conversion circuits. Note
2507 -- that the back end always treats fixed-point as equivalent to the
2508 -- corresponding integer type anyway.
2510 when Attribute_Integer_Value => Integer_Value :
2513 Make_Type_Conversion (Loc,
2514 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2515 Expression => Relocate_Node (First (Exprs))));
2516 Set_Etype (N, Entity (Pref));
2519 -- Note: it might appear that a properly analyzed unchecked conversion
2520 -- would be just fine here, but that's not the case, since the full
2521 -- range checks performed by the following call are critical!
2523 Apply_Type_Conversion_Checks (N);
2530 when Attribute_Invalid_Value =>
2531 Rewrite (N, Get_Simple_Init_Val (Ptyp, N));
2537 when Attribute_Last =>
2539 -- If the prefix type is a constrained packed array type which
2540 -- already has a Packed_Array_Type representation defined, then
2541 -- replace this attribute with a direct reference to 'Last of the
2542 -- appropriate index subtype (since otherwise the back end will try
2543 -- to give us the value of 'Last for this implementation type).
2545 if Is_Constrained_Packed_Array (Ptyp) then
2547 Make_Attribute_Reference (Loc,
2548 Attribute_Name => Name_Last,
2549 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
2550 Analyze_And_Resolve (N, Typ);
2552 elsif Is_Access_Type (Ptyp) then
2553 Apply_Access_Check (N);
2560 -- We compute this if a component clause was present, otherwise we leave
2561 -- the computation up to the back end, since we don't know what layout
2564 when Attribute_Last_Bit => Last_Bit : declare
2565 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2568 if Known_Static_Component_Bit_Offset (CE)
2569 and then Known_Static_Esize (CE)
2572 Make_Integer_Literal (Loc,
2573 Intval => (Component_Bit_Offset (CE) mod System_Storage_Unit)
2576 Analyze_And_Resolve (N, Typ);
2579 Apply_Universal_Integer_Attribute_Checks (N);
2587 -- Transforms 'Leading_Part into a call to the floating-point attribute
2588 -- function Leading_Part in Fat_xxx (where xxx is the root type)
2590 -- Note: strictly, we should generate special case code to deal with
2591 -- absurdly large positive arguments (greater than Integer'Last), which
2592 -- result in returning the first argument unchanged, but it hardly seems
2593 -- worth the effort. We raise constraint error for absurdly negative
2594 -- arguments which is fine.
2596 when Attribute_Leading_Part =>
2597 Expand_Fpt_Attribute_RI (N);
2603 when Attribute_Length => declare
2608 -- Processing for packed array types
2610 if Is_Array_Type (Ptyp) and then Is_Packed (Ptyp) then
2611 Ityp := Get_Index_Subtype (N);
2613 -- If the index type, Ityp, is an enumeration type with holes,
2614 -- then we calculate X'Length explicitly using
2617 -- (0, Ityp'Pos (X'Last (N)) -
2618 -- Ityp'Pos (X'First (N)) + 1);
2620 -- Since the bounds in the template are the representation values
2621 -- and the back end would get the wrong value.
2623 if Is_Enumeration_Type (Ityp)
2624 and then Present (Enum_Pos_To_Rep (Base_Type (Ityp)))
2629 Xnum := Expr_Value (First (Expressions (N)));
2633 Make_Attribute_Reference (Loc,
2634 Prefix => New_Occurrence_Of (Typ, Loc),
2635 Attribute_Name => Name_Max,
2636 Expressions => New_List
2637 (Make_Integer_Literal (Loc, 0),
2641 Make_Op_Subtract (Loc,
2643 Make_Attribute_Reference (Loc,
2644 Prefix => New_Occurrence_Of (Ityp, Loc),
2645 Attribute_Name => Name_Pos,
2647 Expressions => New_List (
2648 Make_Attribute_Reference (Loc,
2649 Prefix => Duplicate_Subexpr (Pref),
2650 Attribute_Name => Name_Last,
2651 Expressions => New_List (
2652 Make_Integer_Literal (Loc, Xnum))))),
2655 Make_Attribute_Reference (Loc,
2656 Prefix => New_Occurrence_Of (Ityp, Loc),
2657 Attribute_Name => Name_Pos,
2659 Expressions => New_List (
2660 Make_Attribute_Reference (Loc,
2662 Duplicate_Subexpr_No_Checks (Pref),
2663 Attribute_Name => Name_First,
2664 Expressions => New_List (
2665 Make_Integer_Literal (Loc, Xnum)))))),
2667 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
2669 Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
2672 -- If the prefix type is a constrained packed array type which
2673 -- already has a Packed_Array_Type representation defined, then
2674 -- replace this attribute with a direct reference to 'Range_Length
2675 -- of the appropriate index subtype (since otherwise the back end
2676 -- will try to give us the value of 'Length for this
2677 -- implementation type).
2679 elsif Is_Constrained (Ptyp) then
2681 Make_Attribute_Reference (Loc,
2682 Attribute_Name => Name_Range_Length,
2683 Prefix => New_Reference_To (Ityp, Loc)));
2684 Analyze_And_Resolve (N, Typ);
2689 elsif Is_Access_Type (Ptyp) then
2690 Apply_Access_Check (N);
2692 -- If the designated type is a packed array type, then we convert
2693 -- the reference to:
2696 -- xtyp'Pos (Pref'Last (Expr)) -
2697 -- xtyp'Pos (Pref'First (Expr)));
2699 -- This is a bit complex, but it is the easiest thing to do that
2700 -- works in all cases including enum types with holes xtyp here
2701 -- is the appropriate index type.
2704 Dtyp : constant Entity_Id := Designated_Type (Ptyp);
2708 if Is_Array_Type (Dtyp) and then Is_Packed (Dtyp) then
2709 Xtyp := Get_Index_Subtype (N);
2712 Make_Attribute_Reference (Loc,
2713 Prefix => New_Occurrence_Of (Typ, Loc),
2714 Attribute_Name => Name_Max,
2715 Expressions => New_List (
2716 Make_Integer_Literal (Loc, 0),
2719 Make_Integer_Literal (Loc, 1),
2720 Make_Op_Subtract (Loc,
2722 Make_Attribute_Reference (Loc,
2723 Prefix => New_Occurrence_Of (Xtyp, Loc),
2724 Attribute_Name => Name_Pos,
2725 Expressions => New_List (
2726 Make_Attribute_Reference (Loc,
2727 Prefix => Duplicate_Subexpr (Pref),
2728 Attribute_Name => Name_Last,
2730 New_Copy_List (Exprs)))),
2733 Make_Attribute_Reference (Loc,
2734 Prefix => New_Occurrence_Of (Xtyp, Loc),
2735 Attribute_Name => Name_Pos,
2736 Expressions => New_List (
2737 Make_Attribute_Reference (Loc,
2739 Duplicate_Subexpr_No_Checks (Pref),
2740 Attribute_Name => Name_First,
2742 New_Copy_List (Exprs)))))))));
2744 Analyze_And_Resolve (N, Typ);
2748 -- Otherwise leave it to the back end
2751 Apply_Universal_Integer_Attribute_Checks (N);
2759 -- Transforms 'Machine into a call to the floating-point attribute
2760 -- function Machine in Fat_xxx (where xxx is the root type)
2762 when Attribute_Machine =>
2763 Expand_Fpt_Attribute_R (N);
2765 ----------------------
2766 -- Machine_Rounding --
2767 ----------------------
2769 -- Transforms 'Machine_Rounding into a call to the floating-point
2770 -- attribute function Machine_Rounding in Fat_xxx (where xxx is the root
2771 -- type). Expansion is avoided for cases the back end can handle
2774 when Attribute_Machine_Rounding =>
2775 if not Is_Inline_Floating_Point_Attribute (N) then
2776 Expand_Fpt_Attribute_R (N);
2783 -- Machine_Size is equivalent to Object_Size, so transform it into
2784 -- Object_Size and that way the back end never sees Machine_Size.
2786 when Attribute_Machine_Size =>
2788 Make_Attribute_Reference (Loc,
2789 Prefix => Prefix (N),
2790 Attribute_Name => Name_Object_Size));
2792 Analyze_And_Resolve (N, Typ);
2798 -- The only case that can get this far is the dynamic case of the old
2799 -- Ada 83 Mantissa attribute for the fixed-point case. For this case,
2806 -- ityp (System.Mantissa.Mantissa_Value
2807 -- (Integer'Integer_Value (typ'First),
2808 -- Integer'Integer_Value (typ'Last)));
2810 when Attribute_Mantissa => Mantissa : begin
2813 Make_Function_Call (Loc,
2814 Name => New_Occurrence_Of (RTE (RE_Mantissa_Value), Loc),
2816 Parameter_Associations => New_List (
2818 Make_Attribute_Reference (Loc,
2819 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2820 Attribute_Name => Name_Integer_Value,
2821 Expressions => New_List (
2823 Make_Attribute_Reference (Loc,
2824 Prefix => New_Occurrence_Of (Ptyp, Loc),
2825 Attribute_Name => Name_First))),
2827 Make_Attribute_Reference (Loc,
2828 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2829 Attribute_Name => Name_Integer_Value,
2830 Expressions => New_List (
2832 Make_Attribute_Reference (Loc,
2833 Prefix => New_Occurrence_Of (Ptyp, Loc),
2834 Attribute_Name => Name_Last)))))));
2836 Analyze_And_Resolve (N, Typ);
2839 --------------------
2840 -- Mechanism_Code --
2841 --------------------
2843 when Attribute_Mechanism_Code =>
2845 -- We must replace the prefix in the renamed case
2847 if Is_Entity_Name (Pref)
2848 and then Present (Alias (Entity (Pref)))
2850 Set_Renamed_Subprogram (Pref, Alias (Entity (Pref)));
2857 when Attribute_Mod => Mod_Case : declare
2858 Arg : constant Node_Id := Relocate_Node (First (Exprs));
2859 Hi : constant Node_Id := Type_High_Bound (Etype (Arg));
2860 Modv : constant Uint := Modulus (Btyp);
2864 -- This is not so simple. The issue is what type to use for the
2865 -- computation of the modular value.
2867 -- The easy case is when the modulus value is within the bounds
2868 -- of the signed integer type of the argument. In this case we can
2869 -- just do the computation in that signed integer type, and then
2870 -- do an ordinary conversion to the target type.
2872 if Modv <= Expr_Value (Hi) then
2877 Right_Opnd => Make_Integer_Literal (Loc, Modv))));
2879 -- Here we know that the modulus is larger than type'Last of the
2880 -- integer type. There are two cases to consider:
2882 -- a) The integer value is non-negative. In this case, it is
2883 -- returned as the result (since it is less than the modulus).
2885 -- b) The integer value is negative. In this case, we know that the
2886 -- result is modulus + value, where the value might be as small as
2887 -- -modulus. The trouble is what type do we use to do the subtract.
2888 -- No type will do, since modulus can be as big as 2**64, and no
2889 -- integer type accommodates this value. Let's do bit of algebra
2892 -- = modulus - (-value)
2893 -- = (modulus - 1) - (-value - 1)
2895 -- Now modulus - 1 is certainly in range of the modular type.
2896 -- -value is in the range 1 .. modulus, so -value -1 is in the
2897 -- range 0 .. modulus-1 which is in range of the modular type.
2898 -- Furthermore, (-value - 1) can be expressed as -(value + 1)
2899 -- which we can compute using the integer base type.
2901 -- Once this is done we analyze the conditional expression without
2902 -- range checks, because we know everything is in range, and we
2903 -- want to prevent spurious warnings on either branch.
2907 Make_Conditional_Expression (Loc,
2908 Expressions => New_List (
2910 Left_Opnd => Duplicate_Subexpr (Arg),
2911 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2914 Duplicate_Subexpr_No_Checks (Arg)),
2916 Make_Op_Subtract (Loc,
2918 Make_Integer_Literal (Loc,
2919 Intval => Modv - 1),
2925 Left_Opnd => Duplicate_Subexpr_No_Checks (Arg),
2927 Make_Integer_Literal (Loc,
2928 Intval => 1))))))));
2932 Analyze_And_Resolve (N, Btyp, Suppress => All_Checks);
2939 -- Transforms 'Model into a call to the floating-point attribute
2940 -- function Model in Fat_xxx (where xxx is the root type)
2942 when Attribute_Model =>
2943 Expand_Fpt_Attribute_R (N);
2949 -- The processing for Object_Size shares the processing for Size
2955 when Attribute_Old => Old : declare
2956 Tnn : constant Entity_Id :=
2957 Make_Defining_Identifier (Loc,
2958 Chars => New_Internal_Name ('T'));
2963 -- Find the nearest subprogram body, ignoring _Preconditions
2967 Subp := Parent (Subp);
2968 exit when Nkind (Subp) = N_Subprogram_Body
2969 and then Chars (Defining_Entity (Subp)) /= Name_uPostconditions;
2972 -- Insert the assignment at the start of the declarations
2975 Make_Object_Declaration (Loc,
2976 Defining_Identifier => Tnn,
2977 Constant_Present => True,
2978 Object_Definition => New_Occurrence_Of (Etype (N), Loc),
2979 Expression => Pref);
2981 if Is_Empty_List (Declarations (Subp)) then
2982 Set_Declarations (Subp, New_List (Asn_Stm));
2985 Insert_Action (First (Declarations (Subp)), Asn_Stm);
2988 Rewrite (N, New_Occurrence_Of (Tnn, Loc));
2995 when Attribute_Output => Output : declare
2996 P_Type : constant Entity_Id := Entity (Pref);
2997 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3005 -- If no underlying type, we have an error that will be diagnosed
3006 -- elsewhere, so here we just completely ignore the expansion.
3012 -- If TSS for Output is present, just call it
3014 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Output);
3016 if Present (Pname) then
3020 -- If there is a Stream_Convert pragma, use it, we rewrite
3022 -- sourcetyp'Output (stream, Item)
3026 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
3028 -- where strmwrite is the given Write function that converts an
3029 -- argument of type sourcetyp or a type acctyp, from which it is
3030 -- derived to type strmtyp. The conversion to acttyp is required
3031 -- for the derived case.
3033 Prag := Get_Stream_Convert_Pragma (P_Type);
3035 if Present (Prag) then
3037 Next (Next (First (Pragma_Argument_Associations (Prag))));
3038 Wfunc := Entity (Expression (Arg3));
3041 Make_Attribute_Reference (Loc,
3042 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
3043 Attribute_Name => Name_Output,
3044 Expressions => New_List (
3045 Relocate_Node (First (Exprs)),
3046 Make_Function_Call (Loc,
3047 Name => New_Occurrence_Of (Wfunc, Loc),
3048 Parameter_Associations => New_List (
3049 OK_Convert_To (Etype (First_Formal (Wfunc)),
3050 Relocate_Node (Next (First (Exprs)))))))));
3055 -- For elementary types, we call the W_xxx routine directly.
3056 -- Note that the effect of Write and Output is identical for
3057 -- the case of an elementary type, since there are no
3058 -- discriminants or bounds.
3060 elsif Is_Elementary_Type (U_Type) then
3062 -- A special case arises if we have a defined _Write routine,
3063 -- since in this case we are required to call this routine.
3065 if Present (TSS (Base_Type (U_Type), TSS_Stream_Write)) then
3066 Build_Record_Or_Elementary_Output_Procedure
3067 (Loc, U_Type, Decl, Pname);
3068 Insert_Action (N, Decl);
3070 -- For normal cases, we call the W_xxx routine directly
3073 Rewrite (N, Build_Elementary_Write_Call (N));
3080 elsif Is_Array_Type (U_Type) then
3081 Build_Array_Output_Procedure (Loc, U_Type, Decl, Pname);
3082 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3084 -- Class-wide case, first output external tag, then dispatch
3085 -- to the appropriate primitive Output function (RM 13.13.2(31)).
3087 elsif Is_Class_Wide_Type (P_Type) then
3089 -- No need to do anything else compiling under restriction
3090 -- No_Dispatching_Calls. During the semantic analysis we
3091 -- already notified such violation.
3093 if Restriction_Active (No_Dispatching_Calls) then
3098 Strm : constant Node_Id := First (Exprs);
3099 Item : constant Node_Id := Next (Strm);
3102 -- Ada 2005 (AI-344): Check that the accessibility level
3103 -- of the type of the output object is not deeper than
3104 -- that of the attribute's prefix type.
3106 -- if Get_Access_Level (Item'Tag)
3107 -- /= Get_Access_Level (P_Type'Tag)
3112 -- String'Output (Strm, External_Tag (Item'Tag));
3114 -- We cannot figure out a practical way to implement this
3115 -- accessibility check on virtual machines, so we omit it.
3117 if Ada_Version >= Ada_05
3118 and then VM_Target = No_VM
3121 Make_Implicit_If_Statement (N,
3125 Build_Get_Access_Level (Loc,
3126 Make_Attribute_Reference (Loc,
3129 Duplicate_Subexpr (Item,
3131 Attribute_Name => Name_Tag)),
3134 Make_Integer_Literal (Loc,
3135 Type_Access_Level (P_Type))),
3138 New_List (Make_Raise_Statement (Loc,
3140 RTE (RE_Tag_Error), Loc)))));
3144 Make_Attribute_Reference (Loc,
3145 Prefix => New_Occurrence_Of (Standard_String, Loc),
3146 Attribute_Name => Name_Output,
3147 Expressions => New_List (
3148 Relocate_Node (Duplicate_Subexpr (Strm)),
3149 Make_Function_Call (Loc,
3151 New_Occurrence_Of (RTE (RE_External_Tag), Loc),
3152 Parameter_Associations => New_List (
3153 Make_Attribute_Reference (Loc,
3156 (Duplicate_Subexpr (Item, Name_Req => True)),
3157 Attribute_Name => Name_Tag))))));
3160 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
3162 -- Tagged type case, use the primitive Output function
3164 elsif Is_Tagged_Type (U_Type) then
3165 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
3167 -- All other record type cases, including protected records.
3168 -- The latter only arise for expander generated code for
3169 -- handling shared passive partition access.
3173 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3175 -- Ada 2005 (AI-216): Program_Error is raised when executing
3176 -- the default implementation of the Output attribute of an
3177 -- unchecked union type if the type lacks default discriminant
3180 if Is_Unchecked_Union (Base_Type (U_Type))
3181 and then No (Discriminant_Constraint (U_Type))
3184 Make_Raise_Program_Error (Loc,
3185 Reason => PE_Unchecked_Union_Restriction));
3190 Build_Record_Or_Elementary_Output_Procedure
3191 (Loc, Base_Type (U_Type), Decl, Pname);
3192 Insert_Action (N, Decl);
3196 -- If we fall through, Pname is the name of the procedure to call
3198 Rewrite_Stream_Proc_Call (Pname);
3205 -- For enumeration types with a standard representation, Pos is
3206 -- handled by the back end.
3208 -- For enumeration types, with a non-standard representation we
3209 -- generate a call to the _Rep_To_Pos function created when the
3210 -- type was frozen. The call has the form
3212 -- _rep_to_pos (expr, flag)
3214 -- The parameter flag is True if range checks are enabled, causing
3215 -- Program_Error to be raised if the expression has an invalid
3216 -- representation, and False if range checks are suppressed.
3218 -- For integer types, Pos is equivalent to a simple integer
3219 -- conversion and we rewrite it as such
3221 when Attribute_Pos => Pos :
3223 Etyp : Entity_Id := Base_Type (Entity (Pref));
3226 -- Deal with zero/non-zero boolean values
3228 if Is_Boolean_Type (Etyp) then
3229 Adjust_Condition (First (Exprs));
3230 Etyp := Standard_Boolean;
3231 Set_Prefix (N, New_Occurrence_Of (Standard_Boolean, Loc));
3234 -- Case of enumeration type
3236 if Is_Enumeration_Type (Etyp) then
3238 -- Non-standard enumeration type (generate call)
3240 if Present (Enum_Pos_To_Rep (Etyp)) then
3241 Append_To (Exprs, Rep_To_Pos_Flag (Etyp, Loc));
3244 Make_Function_Call (Loc,
3246 New_Reference_To (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3247 Parameter_Associations => Exprs)));
3249 Analyze_And_Resolve (N, Typ);
3251 -- Standard enumeration type (do universal integer check)
3254 Apply_Universal_Integer_Attribute_Checks (N);
3257 -- Deal with integer types (replace by conversion)
3259 elsif Is_Integer_Type (Etyp) then
3260 Rewrite (N, Convert_To (Typ, First (Exprs)));
3261 Analyze_And_Resolve (N, Typ);
3270 -- We compute this if a component clause was present, otherwise we leave
3271 -- the computation up to the back end, since we don't know what layout
3274 when Attribute_Position => Position :
3276 CE : constant Entity_Id := Entity (Selector_Name (Pref));
3279 if Present (Component_Clause (CE)) then
3281 Make_Integer_Literal (Loc,
3282 Intval => Component_Bit_Offset (CE) / System_Storage_Unit));
3283 Analyze_And_Resolve (N, Typ);
3286 Apply_Universal_Integer_Attribute_Checks (N);
3294 -- 1. Deal with enumeration types with holes
3295 -- 2. For floating-point, generate call to attribute function
3296 -- 3. For other cases, deal with constraint checking
3298 when Attribute_Pred => Pred :
3300 Etyp : constant Entity_Id := Base_Type (Ptyp);
3304 -- For enumeration types with non-standard representations, we
3305 -- expand typ'Pred (x) into
3307 -- Pos_To_Rep (Rep_To_Pos (x) - 1)
3309 -- If the representation is contiguous, we compute instead
3310 -- Lit1 + Rep_to_Pos (x -1), to catch invalid representations.
3311 -- The conversion function Enum_Pos_To_Rep is defined on the
3312 -- base type, not the subtype, so we have to use the base type
3313 -- explicitly for this and other enumeration attributes.
3315 if Is_Enumeration_Type (Ptyp)
3316 and then Present (Enum_Pos_To_Rep (Etyp))
3318 if Has_Contiguous_Rep (Etyp) then
3320 Unchecked_Convert_To (Ptyp,
3323 Make_Integer_Literal (Loc,
3324 Enumeration_Rep (First_Literal (Ptyp))),
3326 Make_Function_Call (Loc,
3329 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3331 Parameter_Associations =>
3333 Unchecked_Convert_To (Ptyp,
3334 Make_Op_Subtract (Loc,
3336 Unchecked_Convert_To (Standard_Integer,
3337 Relocate_Node (First (Exprs))),
3339 Make_Integer_Literal (Loc, 1))),
3340 Rep_To_Pos_Flag (Ptyp, Loc))))));
3343 -- Add Boolean parameter True, to request program errror if
3344 -- we have a bad representation on our hands. If checks are
3345 -- suppressed, then add False instead
3347 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
3349 Make_Indexed_Component (Loc,
3352 (Enum_Pos_To_Rep (Etyp), Loc),
3353 Expressions => New_List (
3354 Make_Op_Subtract (Loc,
3356 Make_Function_Call (Loc,
3359 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3360 Parameter_Associations => Exprs),
3361 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
3364 Analyze_And_Resolve (N, Typ);
3366 -- For floating-point, we transform 'Pred into a call to the Pred
3367 -- floating-point attribute function in Fat_xxx (xxx is root type)
3369 elsif Is_Floating_Point_Type (Ptyp) then
3370 Expand_Fpt_Attribute_R (N);
3371 Analyze_And_Resolve (N, Typ);
3373 -- For modular types, nothing to do (no overflow, since wraps)
3375 elsif Is_Modular_Integer_Type (Ptyp) then
3378 -- For other types, if range checking is enabled, we must generate
3379 -- a check if overflow checking is enabled.
3381 elsif not Overflow_Checks_Suppressed (Ptyp) then
3382 Expand_Pred_Succ (N);
3390 -- Ada 2005 (AI-327): Dynamic ceiling priorities
3392 -- We rewrite X'Priority as the following run-time call:
3394 -- Get_Ceiling (X._Object)
3396 -- Note that although X'Priority is notionally an object, it is quite
3397 -- deliberately not defined as an aliased object in the RM. This means
3398 -- that it works fine to rewrite it as a call, without having to worry
3399 -- about complications that would other arise from X'Priority'Access,
3400 -- which is illegal, because of the lack of aliasing.
3402 when Attribute_Priority =>
3405 Conctyp : Entity_Id;
3406 Object_Parm : Node_Id;
3408 RT_Subprg_Name : Node_Id;
3411 -- Look for the enclosing concurrent type
3413 Conctyp := Current_Scope;
3414 while not Is_Concurrent_Type (Conctyp) loop
3415 Conctyp := Scope (Conctyp);
3418 pragma Assert (Is_Protected_Type (Conctyp));
3420 -- Generate the actual of the call
3422 Subprg := Current_Scope;
3423 while not Present (Protected_Body_Subprogram (Subprg)) loop
3424 Subprg := Scope (Subprg);
3427 -- Use of 'Priority inside protected entries and barriers (in
3428 -- both cases the type of the first formal of their expanded
3429 -- subprogram is Address)
3431 if Etype (First_Entity (Protected_Body_Subprogram (Subprg)))
3435 New_Itype : Entity_Id;
3438 -- In the expansion of protected entries the type of the
3439 -- first formal of the Protected_Body_Subprogram is an
3440 -- Address. In order to reference the _object component
3443 -- type T is access p__ptTV;
3446 New_Itype := Create_Itype (E_Access_Type, N);
3447 Set_Etype (New_Itype, New_Itype);
3448 Set_Directly_Designated_Type (New_Itype,
3449 Corresponding_Record_Type (Conctyp));
3450 Freeze_Itype (New_Itype, N);
3453 -- T!(O)._object'unchecked_access
3456 Make_Attribute_Reference (Loc,
3458 Make_Selected_Component (Loc,
3460 Unchecked_Convert_To (New_Itype,
3463 (Protected_Body_Subprogram (Subprg)),
3466 Make_Identifier (Loc, Name_uObject)),
3467 Attribute_Name => Name_Unchecked_Access);
3470 -- Use of 'Priority inside a protected subprogram
3474 Make_Attribute_Reference (Loc,
3476 Make_Selected_Component (Loc,
3477 Prefix => New_Reference_To
3479 (Protected_Body_Subprogram (Subprg)),
3482 Make_Identifier (Loc, Name_uObject)),
3483 Attribute_Name => Name_Unchecked_Access);
3486 -- Select the appropriate run-time subprogram
3488 if Number_Entries (Conctyp) = 0 then
3490 New_Reference_To (RTE (RE_Get_Ceiling), Loc);
3493 New_Reference_To (RTE (RO_PE_Get_Ceiling), Loc);
3497 Make_Function_Call (Loc,
3498 Name => RT_Subprg_Name,
3499 Parameter_Associations => New_List (Object_Parm));
3503 -- Avoid the generation of extra checks on the pointer to the
3504 -- protected object.
3506 Analyze_And_Resolve (N, Typ, Suppress => Access_Check);
3513 when Attribute_Range_Length => Range_Length : begin
3514 -- The only special processing required is for the case where
3515 -- Range_Length is applied to an enumeration type with holes.
3516 -- In this case we transform
3522 -- X'Pos (X'Last) - X'Pos (X'First) + 1
3524 -- So that the result reflects the proper Pos values instead
3525 -- of the underlying representations.
3527 if Is_Enumeration_Type (Ptyp)
3528 and then Has_Non_Standard_Rep (Ptyp)
3533 Make_Op_Subtract (Loc,
3535 Make_Attribute_Reference (Loc,
3536 Attribute_Name => Name_Pos,
3537 Prefix => New_Occurrence_Of (Ptyp, Loc),
3538 Expressions => New_List (
3539 Make_Attribute_Reference (Loc,
3540 Attribute_Name => Name_Last,
3541 Prefix => New_Occurrence_Of (Ptyp, Loc)))),
3544 Make_Attribute_Reference (Loc,
3545 Attribute_Name => Name_Pos,
3546 Prefix => New_Occurrence_Of (Ptyp, Loc),
3547 Expressions => New_List (
3548 Make_Attribute_Reference (Loc,
3549 Attribute_Name => Name_First,
3550 Prefix => New_Occurrence_Of (Ptyp, Loc))))),
3553 Make_Integer_Literal (Loc, 1)));
3555 Analyze_And_Resolve (N, Typ);
3557 -- For all other cases, the attribute is handled by the back end, but
3558 -- we need to deal with the case of the range check on a universal
3562 Apply_Universal_Integer_Attribute_Checks (N);
3570 when Attribute_Read => Read : declare
3571 P_Type : constant Entity_Id := Entity (Pref);
3572 B_Type : constant Entity_Id := Base_Type (P_Type);
3573 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3583 -- If no underlying type, we have an error that will be diagnosed
3584 -- elsewhere, so here we just completely ignore the expansion.
3590 -- The simple case, if there is a TSS for Read, just call it
3592 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Read);
3594 if Present (Pname) then
3598 -- If there is a Stream_Convert pragma, use it, we rewrite
3600 -- sourcetyp'Read (stream, Item)
3604 -- Item := sourcetyp (strmread (strmtyp'Input (Stream)));
3606 -- where strmread is the given Read function that converts an
3607 -- argument of type strmtyp to type sourcetyp or a type from which
3608 -- it is derived. The conversion to sourcetyp is required in the
3611 -- A special case arises if Item is a type conversion in which
3612 -- case, we have to expand to:
3614 -- Itemx := typex (strmread (strmtyp'Input (Stream)));
3616 -- where Itemx is the expression of the type conversion (i.e.
3617 -- the actual object), and typex is the type of Itemx.
3619 Prag := Get_Stream_Convert_Pragma (P_Type);
3621 if Present (Prag) then
3622 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
3623 Rfunc := Entity (Expression (Arg2));
3624 Lhs := Relocate_Node (Next (First (Exprs)));
3626 OK_Convert_To (B_Type,
3627 Make_Function_Call (Loc,
3628 Name => New_Occurrence_Of (Rfunc, Loc),
3629 Parameter_Associations => New_List (
3630 Make_Attribute_Reference (Loc,
3633 (Etype (First_Formal (Rfunc)), Loc),
3634 Attribute_Name => Name_Input,
3635 Expressions => New_List (
3636 Relocate_Node (First (Exprs)))))));
3638 if Nkind (Lhs) = N_Type_Conversion then
3639 Lhs := Expression (Lhs);
3640 Rhs := Convert_To (Etype (Lhs), Rhs);
3644 Make_Assignment_Statement (Loc,
3646 Expression => Rhs));
3647 Set_Assignment_OK (Lhs);
3651 -- For elementary types, we call the I_xxx routine using the first
3652 -- parameter and then assign the result into the second parameter.
3653 -- We set Assignment_OK to deal with the conversion case.
3655 elsif Is_Elementary_Type (U_Type) then
3661 Lhs := Relocate_Node (Next (First (Exprs)));
3662 Rhs := Build_Elementary_Input_Call (N);
3664 if Nkind (Lhs) = N_Type_Conversion then
3665 Lhs := Expression (Lhs);
3666 Rhs := Convert_To (Etype (Lhs), Rhs);
3669 Set_Assignment_OK (Lhs);
3672 Make_Assignment_Statement (Loc,
3674 Expression => Rhs));
3682 elsif Is_Array_Type (U_Type) then
3683 Build_Array_Read_Procedure (N, U_Type, Decl, Pname);
3684 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3686 -- Tagged type case, use the primitive Read function. Note that
3687 -- this will dispatch in the class-wide case which is what we want
3689 elsif Is_Tagged_Type (U_Type) then
3690 Pname := Find_Prim_Op (U_Type, TSS_Stream_Read);
3692 -- All other record type cases, including protected records. The
3693 -- latter only arise for expander generated code for handling
3694 -- shared passive partition access.
3698 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3700 -- Ada 2005 (AI-216): Program_Error is raised when executing
3701 -- the default implementation of the Read attribute of an
3702 -- Unchecked_Union type.
3704 if Is_Unchecked_Union (Base_Type (U_Type)) then
3706 Make_Raise_Program_Error (Loc,
3707 Reason => PE_Unchecked_Union_Restriction));
3710 if Has_Discriminants (U_Type)
3712 (Discriminant_Default_Value (First_Discriminant (U_Type)))
3714 Build_Mutable_Record_Read_Procedure
3715 (Loc, Base_Type (U_Type), Decl, Pname);
3717 Build_Record_Read_Procedure
3718 (Loc, Base_Type (U_Type), Decl, Pname);
3721 -- Suppress checks, uninitialized or otherwise invalid
3722 -- data does not cause constraint errors to be raised for
3723 -- a complete record read.
3725 Insert_Action (N, Decl, All_Checks);
3729 Rewrite_Stream_Proc_Call (Pname);
3736 -- Transforms 'Remainder into a call to the floating-point attribute
3737 -- function Remainder in Fat_xxx (where xxx is the root type)
3739 when Attribute_Remainder =>
3740 Expand_Fpt_Attribute_RR (N);
3746 -- Transform 'Result into reference to _Result formal. At the point
3747 -- where a legal 'Result attribute is expanded, we know that we are in
3748 -- the context of a _Postcondition function with a _Result parameter.
3750 when Attribute_Result =>
3752 Make_Identifier (Loc,
3753 Chars => Name_uResult));
3754 Analyze_And_Resolve (N, Typ);
3760 -- The handling of the Round attribute is quite delicate. The processing
3761 -- in Sem_Attr introduced a conversion to universal real, reflecting the
3762 -- semantics of Round, but we do not want anything to do with universal
3763 -- real at runtime, since this corresponds to using floating-point
3766 -- What we have now is that the Etype of the Round attribute correctly
3767 -- indicates the final result type. The operand of the Round is the
3768 -- conversion to universal real, described above, and the operand of
3769 -- this conversion is the actual operand of Round, which may be the
3770 -- special case of a fixed point multiplication or division (Etype =
3773 -- The exapander will expand first the operand of the conversion, then
3774 -- the conversion, and finally the round attribute itself, since we
3775 -- always work inside out. But we cannot simply process naively in this
3776 -- order. In the semantic world where universal fixed and real really
3777 -- exist and have infinite precision, there is no problem, but in the
3778 -- implementation world, where universal real is a floating-point type,
3779 -- we would get the wrong result.
3781 -- So the approach is as follows. First, when expanding a multiply or
3782 -- divide whose type is universal fixed, we do nothing at all, instead
3783 -- deferring the operation till later.
3785 -- The actual processing is done in Expand_N_Type_Conversion which
3786 -- handles the special case of Round by looking at its parent to see if
3787 -- it is a Round attribute, and if it is, handling the conversion (or
3788 -- its fixed multiply/divide child) in an appropriate manner.
3790 -- This means that by the time we get to expanding the Round attribute
3791 -- itself, the Round is nothing more than a type conversion (and will
3792 -- often be a null type conversion), so we just replace it with the
3793 -- appropriate conversion operation.
3795 when Attribute_Round =>
3797 Convert_To (Etype (N), Relocate_Node (First (Exprs))));
3798 Analyze_And_Resolve (N);
3804 -- Transforms 'Rounding into a call to the floating-point attribute
3805 -- function Rounding in Fat_xxx (where xxx is the root type)
3807 when Attribute_Rounding =>
3808 Expand_Fpt_Attribute_R (N);
3814 -- Transforms 'Scaling into a call to the floating-point attribute
3815 -- function Scaling in Fat_xxx (where xxx is the root type)
3817 when Attribute_Scaling =>
3818 Expand_Fpt_Attribute_RI (N);
3824 when Attribute_Size |
3825 Attribute_Object_Size |
3826 Attribute_Value_Size |
3827 Attribute_VADS_Size => Size :
3834 -- Processing for VADS_Size case. Note that this processing removes
3835 -- all traces of VADS_Size from the tree, and completes all required
3836 -- processing for VADS_Size by translating the attribute reference
3837 -- to an appropriate Size or Object_Size reference.
3839 if Id = Attribute_VADS_Size
3840 or else (Use_VADS_Size and then Id = Attribute_Size)
3842 -- If the size is specified, then we simply use the specified
3843 -- size. This applies to both types and objects. The size of an
3844 -- object can be specified in the following ways:
3846 -- An explicit size object is given for an object
3847 -- A component size is specified for an indexed component
3848 -- A component clause is specified for a selected component
3849 -- The object is a component of a packed composite object
3851 -- If the size is specified, then VADS_Size of an object
3853 if (Is_Entity_Name (Pref)
3854 and then Present (Size_Clause (Entity (Pref))))
3856 (Nkind (Pref) = N_Component_Clause
3857 and then (Present (Component_Clause
3858 (Entity (Selector_Name (Pref))))
3859 or else Is_Packed (Etype (Prefix (Pref)))))
3861 (Nkind (Pref) = N_Indexed_Component
3862 and then (Component_Size (Etype (Prefix (Pref))) /= 0
3863 or else Is_Packed (Etype (Prefix (Pref)))))
3865 Set_Attribute_Name (N, Name_Size);
3867 -- Otherwise if we have an object rather than a type, then the
3868 -- VADS_Size attribute applies to the type of the object, rather
3869 -- than the object itself. This is one of the respects in which
3870 -- VADS_Size differs from Size.
3873 if (not Is_Entity_Name (Pref)
3874 or else not Is_Type (Entity (Pref)))
3875 and then (Is_Scalar_Type (Ptyp) or else Is_Constrained (Ptyp))
3877 Rewrite (Pref, New_Occurrence_Of (Ptyp, Loc));
3880 -- For a scalar type for which no size was explicitly given,
3881 -- VADS_Size means Object_Size. This is the other respect in
3882 -- which VADS_Size differs from Size.
3884 if Is_Scalar_Type (Ptyp) and then No (Size_Clause (Ptyp)) then
3885 Set_Attribute_Name (N, Name_Object_Size);
3887 -- In all other cases, Size and VADS_Size are the sane
3890 Set_Attribute_Name (N, Name_Size);
3895 -- For class-wide types, X'Class'Size is transformed into a direct
3896 -- reference to the Size of the class type, so that the back end does
3897 -- not have to deal with the X'Class'Size reference.
3899 if Is_Entity_Name (Pref)
3900 and then Is_Class_Wide_Type (Entity (Pref))
3902 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
3905 -- For X'Size applied to an object of a class-wide type, transform
3906 -- X'Size into a call to the primitive operation _Size applied to X.
3908 elsif Is_Class_Wide_Type (Ptyp) then
3910 -- No need to do anything else compiling under restriction
3911 -- No_Dispatching_Calls. During the semantic analysis we
3912 -- already notified such violation.
3914 if Restriction_Active (No_Dispatching_Calls) then
3919 Make_Function_Call (Loc,
3920 Name => New_Reference_To
3921 (Find_Prim_Op (Ptyp, Name_uSize), Loc),
3922 Parameter_Associations => New_List (Pref));
3924 if Typ /= Standard_Long_Long_Integer then
3926 -- The context is a specific integer type with which the
3927 -- original attribute was compatible. The function has a
3928 -- specific type as well, so to preserve the compatibility
3929 -- we must convert explicitly.
3931 New_Node := Convert_To (Typ, New_Node);
3934 Rewrite (N, New_Node);
3935 Analyze_And_Resolve (N, Typ);
3938 -- Case of known RM_Size of a type
3940 elsif (Id = Attribute_Size or else Id = Attribute_Value_Size)
3941 and then Is_Entity_Name (Pref)
3942 and then Is_Type (Entity (Pref))
3943 and then Known_Static_RM_Size (Entity (Pref))
3945 Siz := RM_Size (Entity (Pref));
3947 -- Case of known Esize of a type
3949 elsif Id = Attribute_Object_Size
3950 and then Is_Entity_Name (Pref)
3951 and then Is_Type (Entity (Pref))
3952 and then Known_Static_Esize (Entity (Pref))
3954 Siz := Esize (Entity (Pref));
3956 -- Case of known size of object
3958 elsif Id = Attribute_Size
3959 and then Is_Entity_Name (Pref)
3960 and then Is_Object (Entity (Pref))
3961 and then Known_Esize (Entity (Pref))
3962 and then Known_Static_Esize (Entity (Pref))
3964 Siz := Esize (Entity (Pref));
3966 -- For an array component, we can do Size in the front end
3967 -- if the component_size of the array is set.
3969 elsif Nkind (Pref) = N_Indexed_Component then
3970 Siz := Component_Size (Etype (Prefix (Pref)));
3972 -- For a record component, we can do Size in the front end if there
3973 -- is a component clause, or if the record is packed and the
3974 -- component's size is known at compile time.
3976 elsif Nkind (Pref) = N_Selected_Component then
3978 Rec : constant Entity_Id := Etype (Prefix (Pref));
3979 Comp : constant Entity_Id := Entity (Selector_Name (Pref));
3982 if Present (Component_Clause (Comp)) then
3983 Siz := Esize (Comp);
3985 elsif Is_Packed (Rec) then
3986 Siz := RM_Size (Ptyp);
3989 Apply_Universal_Integer_Attribute_Checks (N);
3994 -- All other cases are handled by the back end
3997 Apply_Universal_Integer_Attribute_Checks (N);
3999 -- If Size is applied to a formal parameter that is of a packed
4000 -- array subtype, then apply Size to the actual subtype.
4002 if Is_Entity_Name (Pref)
4003 and then Is_Formal (Entity (Pref))
4004 and then Is_Array_Type (Ptyp)
4005 and then Is_Packed (Ptyp)
4008 Make_Attribute_Reference (Loc,
4010 New_Occurrence_Of (Get_Actual_Subtype (Pref), Loc),
4011 Attribute_Name => Name_Size));
4012 Analyze_And_Resolve (N, Typ);
4015 -- If Size applies to a dereference of an access to unconstrained
4016 -- packed array, the back end needs to see its unconstrained
4017 -- nominal type, but also a hint to the actual constrained type.
4019 if Nkind (Pref) = N_Explicit_Dereference
4020 and then Is_Array_Type (Ptyp)
4021 and then not Is_Constrained (Ptyp)
4022 and then Is_Packed (Ptyp)
4024 Set_Actual_Designated_Subtype (Pref,
4025 Get_Actual_Subtype (Pref));
4031 -- Common processing for record and array component case
4033 if Siz /= No_Uint and then Siz /= 0 then
4035 CS : constant Boolean := Comes_From_Source (N);
4038 Rewrite (N, Make_Integer_Literal (Loc, Siz));
4040 -- This integer literal is not a static expression. We do not
4041 -- call Analyze_And_Resolve here, because this would activate
4042 -- the circuit for deciding that a static value was out of
4043 -- range, and we don't want that.
4045 -- So just manually set the type, mark the expression as non-
4046 -- static, and then ensure that the result is checked properly
4047 -- if the attribute comes from source (if it was internally
4048 -- generated, we never need a constraint check).
4051 Set_Is_Static_Expression (N, False);
4054 Apply_Constraint_Check (N, Typ);
4064 when Attribute_Storage_Pool =>
4066 Make_Type_Conversion (Loc,
4067 Subtype_Mark => New_Reference_To (Etype (N), Loc),
4068 Expression => New_Reference_To (Entity (N), Loc)));
4069 Analyze_And_Resolve (N, Typ);
4075 when Attribute_Storage_Size => Storage_Size : begin
4077 -- Access type case, always go to the root type
4079 -- The case of access types results in a value of zero for the case
4080 -- where no storage size attribute clause has been given. If a
4081 -- storage size has been given, then the attribute is converted
4082 -- to a reference to the variable used to hold this value.
4084 if Is_Access_Type (Ptyp) then
4085 if Present (Storage_Size_Variable (Root_Type (Ptyp))) then
4087 Make_Attribute_Reference (Loc,
4088 Prefix => New_Reference_To (Typ, Loc),
4089 Attribute_Name => Name_Max,
4090 Expressions => New_List (
4091 Make_Integer_Literal (Loc, 0),
4094 (Storage_Size_Variable (Root_Type (Ptyp)), Loc)))));
4096 elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then
4099 Make_Function_Call (Loc,
4103 (Etype (Associated_Storage_Pool (Root_Type (Ptyp))),
4104 Attribute_Name (N)),
4107 Parameter_Associations => New_List (
4109 (Associated_Storage_Pool (Root_Type (Ptyp)), Loc)))));
4112 Rewrite (N, Make_Integer_Literal (Loc, 0));
4115 Analyze_And_Resolve (N, Typ);
4117 -- For tasks, we retrieve the size directly from the TCB. The
4118 -- size may depend on a discriminant of the type, and therefore
4119 -- can be a per-object expression, so type-level information is
4120 -- not sufficient in general. There are four cases to consider:
4122 -- a) If the attribute appears within a task body, the designated
4123 -- TCB is obtained by a call to Self.
4125 -- b) If the prefix of the attribute is the name of a task object,
4126 -- the designated TCB is the one stored in the corresponding record.
4128 -- c) If the prefix is a task type, the size is obtained from the
4129 -- size variable created for each task type
4131 -- d) If no storage_size was specified for the type , there is no
4132 -- size variable, and the value is a system-specific default.
4135 if In_Open_Scopes (Ptyp) then
4137 -- Storage_Size (Self)
4141 Make_Function_Call (Loc,
4143 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4144 Parameter_Associations =>
4146 Make_Function_Call (Loc,
4148 New_Reference_To (RTE (RE_Self), Loc))))));
4150 elsif not Is_Entity_Name (Pref)
4151 or else not Is_Type (Entity (Pref))
4153 -- Storage_Size (Rec (Obj).Size)
4157 Make_Function_Call (Loc,
4159 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4160 Parameter_Associations =>
4162 Make_Selected_Component (Loc,
4164 Unchecked_Convert_To (
4165 Corresponding_Record_Type (Ptyp),
4166 New_Copy_Tree (Pref)),
4168 Make_Identifier (Loc, Name_uTask_Id))))));
4170 elsif Present (Storage_Size_Variable (Ptyp)) then
4172 -- Static storage size pragma given for type: retrieve value
4173 -- from its allocated storage variable.
4177 Make_Function_Call (Loc,
4178 Name => New_Occurrence_Of (
4179 RTE (RE_Adjust_Storage_Size), Loc),
4180 Parameter_Associations =>
4183 Storage_Size_Variable (Ptyp), Loc)))));
4185 -- Get system default
4189 Make_Function_Call (Loc,
4192 RTE (RE_Default_Stack_Size), Loc))));
4195 Analyze_And_Resolve (N, Typ);
4203 when Attribute_Stream_Size => Stream_Size : declare
4207 -- If we have a Stream_Size clause for this type use it, otherwise
4208 -- the Stream_Size if the size of the type.
4210 if Has_Stream_Size_Clause (Ptyp) then
4213 (Static_Integer (Expression (Stream_Size_Clause (Ptyp))));
4215 Size := UI_To_Int (Esize (Ptyp));
4218 Rewrite (N, Make_Integer_Literal (Loc, Intval => Size));
4219 Analyze_And_Resolve (N, Typ);
4226 -- 1. Deal with enumeration types with holes
4227 -- 2. For floating-point, generate call to attribute function
4228 -- 3. For other cases, deal with constraint checking
4230 when Attribute_Succ => Succ :
4232 Etyp : constant Entity_Id := Base_Type (Ptyp);
4236 -- For enumeration types with non-standard representations, we
4237 -- expand typ'Succ (x) into
4239 -- Pos_To_Rep (Rep_To_Pos (x) + 1)
4241 -- If the representation is contiguous, we compute instead
4242 -- Lit1 + Rep_to_Pos (x+1), to catch invalid representations.
4244 if Is_Enumeration_Type (Ptyp)
4245 and then Present (Enum_Pos_To_Rep (Etyp))
4247 if Has_Contiguous_Rep (Etyp) then
4249 Unchecked_Convert_To (Ptyp,
4252 Make_Integer_Literal (Loc,
4253 Enumeration_Rep (First_Literal (Ptyp))),
4255 Make_Function_Call (Loc,
4258 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4260 Parameter_Associations =>
4262 Unchecked_Convert_To (Ptyp,
4265 Unchecked_Convert_To (Standard_Integer,
4266 Relocate_Node (First (Exprs))),
4268 Make_Integer_Literal (Loc, 1))),
4269 Rep_To_Pos_Flag (Ptyp, Loc))))));
4271 -- Add Boolean parameter True, to request program errror if
4272 -- we have a bad representation on our hands. Add False if
4273 -- checks are suppressed.
4275 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
4277 Make_Indexed_Component (Loc,
4280 (Enum_Pos_To_Rep (Etyp), Loc),
4281 Expressions => New_List (
4284 Make_Function_Call (Loc,
4287 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4288 Parameter_Associations => Exprs),
4289 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
4292 Analyze_And_Resolve (N, Typ);
4294 -- For floating-point, we transform 'Succ into a call to the Succ
4295 -- floating-point attribute function in Fat_xxx (xxx is root type)
4297 elsif Is_Floating_Point_Type (Ptyp) then
4298 Expand_Fpt_Attribute_R (N);
4299 Analyze_And_Resolve (N, Typ);
4301 -- For modular types, nothing to do (no overflow, since wraps)
4303 elsif Is_Modular_Integer_Type (Ptyp) then
4306 -- For other types, if range checking is enabled, we must generate
4307 -- a check if overflow checking is enabled.
4309 elsif not Overflow_Checks_Suppressed (Ptyp) then
4310 Expand_Pred_Succ (N);
4318 -- Transforms X'Tag into a direct reference to the tag of X
4320 when Attribute_Tag => Tag :
4323 Prefix_Is_Type : Boolean;
4326 if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then
4327 Ttyp := Entity (Pref);
4328 Prefix_Is_Type := True;
4331 Prefix_Is_Type := False;
4334 if Is_Class_Wide_Type (Ttyp) then
4335 Ttyp := Root_Type (Ttyp);
4338 Ttyp := Underlying_Type (Ttyp);
4340 if Prefix_Is_Type then
4342 -- For VMs we leave the type attribute unexpanded because
4343 -- there's not a dispatching table to reference.
4345 if VM_Target = No_VM then
4347 Unchecked_Convert_To (RTE (RE_Tag),
4349 (Node (First_Elmt (Access_Disp_Table (Ttyp))), Loc)));
4350 Analyze_And_Resolve (N, RTE (RE_Tag));
4353 -- (Ada 2005 (AI-251): The use of 'Tag in the sources always
4354 -- references the primary tag of the actual object. If 'Tag is
4355 -- applied to class-wide interface objects we generate code that
4356 -- displaces "this" to reference the base of the object.
4358 elsif Comes_From_Source (N)
4359 and then Is_Class_Wide_Type (Etype (Prefix (N)))
4360 and then Is_Interface (Etype (Prefix (N)))
4363 -- (To_Tag_Ptr (Prefix'Address)).all
4365 -- Note that Prefix'Address is recursively expanded into a call
4366 -- to Base_Address (Obj.Tag)
4368 -- Not needed for VM targets, since all handled by the VM
4370 if VM_Target = No_VM then
4372 Make_Explicit_Dereference (Loc,
4373 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
4374 Make_Attribute_Reference (Loc,
4375 Prefix => Relocate_Node (Pref),
4376 Attribute_Name => Name_Address))));
4377 Analyze_And_Resolve (N, RTE (RE_Tag));
4382 Make_Selected_Component (Loc,
4383 Prefix => Relocate_Node (Pref),
4385 New_Reference_To (First_Tag_Component (Ttyp), Loc)));
4386 Analyze_And_Resolve (N, RTE (RE_Tag));
4394 -- Transforms 'Terminated attribute into a call to Terminated function
4396 when Attribute_Terminated => Terminated :
4398 -- The prefix of Terminated is of a task interface class-wide type.
4401 -- terminated (Task_Id (Pref._disp_get_task_id));
4403 if Ada_Version >= Ada_05
4404 and then Ekind (Ptyp) = E_Class_Wide_Type
4405 and then Is_Interface (Ptyp)
4406 and then Is_Task_Interface (Ptyp)
4409 Make_Function_Call (Loc,
4411 New_Reference_To (RTE (RE_Terminated), Loc),
4412 Parameter_Associations => New_List (
4413 Make_Unchecked_Type_Conversion (Loc,
4415 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
4417 Make_Selected_Component (Loc,
4419 New_Copy_Tree (Pref),
4421 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
4423 elsif Restricted_Profile then
4425 Build_Call_With_Task (Pref, RTE (RE_Restricted_Terminated)));
4429 Build_Call_With_Task (Pref, RTE (RE_Terminated)));
4432 Analyze_And_Resolve (N, Standard_Boolean);
4439 -- Transforms System'To_Address (X) into unchecked conversion
4440 -- from (integral) type of X to type address.
4442 when Attribute_To_Address =>
4444 Unchecked_Convert_To (RTE (RE_Address),
4445 Relocate_Node (First (Exprs))));
4446 Analyze_And_Resolve (N, RTE (RE_Address));
4452 when Attribute_To_Any => To_Any : declare
4453 P_Type : constant Entity_Id := Etype (Pref);
4454 Decls : constant List_Id := New_List;
4458 (Convert_To (P_Type,
4459 Relocate_Node (First (Exprs))), Decls));
4460 Insert_Actions (N, Decls);
4461 Analyze_And_Resolve (N, RTE (RE_Any));
4468 -- Transforms 'Truncation into a call to the floating-point attribute
4469 -- function Truncation in Fat_xxx (where xxx is the root type).
4470 -- Expansion is avoided for cases the back end can handle directly.
4472 when Attribute_Truncation =>
4473 if not Is_Inline_Floating_Point_Attribute (N) then
4474 Expand_Fpt_Attribute_R (N);
4481 when Attribute_TypeCode => TypeCode : declare
4482 P_Type : constant Entity_Id := Etype (Pref);
4483 Decls : constant List_Id := New_List;
4485 Rewrite (N, Build_TypeCode_Call (Loc, P_Type, Decls));
4486 Insert_Actions (N, Decls);
4487 Analyze_And_Resolve (N, RTE (RE_TypeCode));
4490 -----------------------
4491 -- Unbiased_Rounding --
4492 -----------------------
4494 -- Transforms 'Unbiased_Rounding into a call to the floating-point
4495 -- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the
4496 -- root type). Expansion is avoided for cases the back end can handle
4499 when Attribute_Unbiased_Rounding =>
4500 if not Is_Inline_Floating_Point_Attribute (N) then
4501 Expand_Fpt_Attribute_R (N);
4508 when Attribute_UET_Address => UET_Address : declare
4509 Ent : constant Entity_Id :=
4510 Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
4514 Make_Object_Declaration (Loc,
4515 Defining_Identifier => Ent,
4516 Aliased_Present => True,
4517 Object_Definition =>
4518 New_Occurrence_Of (RTE (RE_Address), Loc)));
4520 -- Construct name __gnat_xxx__SDP, where xxx is the unit name
4521 -- in normal external form.
4523 Get_External_Unit_Name_String (Get_Unit_Name (Pref));
4524 Name_Buffer (1 + 7 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
4525 Name_Len := Name_Len + 7;
4526 Name_Buffer (1 .. 7) := "__gnat_";
4527 Name_Buffer (Name_Len + 1 .. Name_Len + 5) := "__SDP";
4528 Name_Len := Name_Len + 5;
4530 Set_Is_Imported (Ent);
4531 Set_Interface_Name (Ent,
4532 Make_String_Literal (Loc,
4533 Strval => String_From_Name_Buffer));
4535 -- Set entity as internal to ensure proper Sprint output of its
4536 -- implicit importation.
4538 Set_Is_Internal (Ent);
4541 Make_Attribute_Reference (Loc,
4542 Prefix => New_Occurrence_Of (Ent, Loc),
4543 Attribute_Name => Name_Address));
4545 Analyze_And_Resolve (N, Typ);
4552 -- The processing for VADS_Size is shared with Size
4558 -- For enumeration types with a standard representation, and for all
4559 -- other types, Val is handled by the back end. For enumeration types
4560 -- with a non-standard representation we use the _Pos_To_Rep array that
4561 -- was created when the type was frozen.
4563 when Attribute_Val => Val :
4565 Etyp : constant Entity_Id := Base_Type (Entity (Pref));
4568 if Is_Enumeration_Type (Etyp)
4569 and then Present (Enum_Pos_To_Rep (Etyp))
4571 if Has_Contiguous_Rep (Etyp) then
4573 Rep_Node : constant Node_Id :=
4574 Unchecked_Convert_To (Etyp,
4577 Make_Integer_Literal (Loc,
4578 Enumeration_Rep (First_Literal (Etyp))),
4580 (Convert_To (Standard_Integer,
4581 Relocate_Node (First (Exprs))))));
4585 Unchecked_Convert_To (Etyp,
4588 Make_Integer_Literal (Loc,
4589 Enumeration_Rep (First_Literal (Etyp))),
4591 Make_Function_Call (Loc,
4594 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4595 Parameter_Associations => New_List (
4597 Rep_To_Pos_Flag (Etyp, Loc))))));
4602 Make_Indexed_Component (Loc,
4603 Prefix => New_Reference_To (Enum_Pos_To_Rep (Etyp), Loc),
4604 Expressions => New_List (
4605 Convert_To (Standard_Integer,
4606 Relocate_Node (First (Exprs))))));
4609 Analyze_And_Resolve (N, Typ);
4617 -- The code for valid is dependent on the particular types involved.
4618 -- See separate sections below for the generated code in each case.
4620 when Attribute_Valid => Valid :
4622 Btyp : Entity_Id := Base_Type (Ptyp);
4625 Save_Validity_Checks_On : constant Boolean := Validity_Checks_On;
4626 -- Save the validity checking mode. We always turn off validity
4627 -- checking during process of 'Valid since this is one place
4628 -- where we do not want the implicit validity checks to intefere
4629 -- with the explicit validity check that the programmer is doing.
4631 function Make_Range_Test return Node_Id;
4632 -- Build the code for a range test of the form
4633 -- Btyp!(Pref) >= Btyp!(Ptyp'First)
4635 -- Btyp!(Pref) <= Btyp!(Ptyp'Last)
4637 ---------------------
4638 -- Make_Range_Test --
4639 ---------------------
4641 function Make_Range_Test return Node_Id is
4648 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
4651 Unchecked_Convert_To (Btyp,
4652 Make_Attribute_Reference (Loc,
4653 Prefix => New_Occurrence_Of (Ptyp, Loc),
4654 Attribute_Name => Name_First))),
4659 Unchecked_Convert_To (Btyp,
4660 Duplicate_Subexpr_No_Checks (Pref)),
4663 Unchecked_Convert_To (Btyp,
4664 Make_Attribute_Reference (Loc,
4665 Prefix => New_Occurrence_Of (Ptyp, Loc),
4666 Attribute_Name => Name_Last))));
4667 end Make_Range_Test;
4669 -- Start of processing for Attribute_Valid
4672 -- Turn off validity checks. We do not want any implicit validity
4673 -- checks to intefere with the explicit check from the attribute
4675 Validity_Checks_On := False;
4677 -- Floating-point case. This case is handled by the Valid attribute
4678 -- code in the floating-point attribute run-time library.
4680 if Is_Floating_Point_Type (Ptyp) then
4686 -- For vax fpt types, call appropriate routine in special vax
4687 -- floating point unit. We do not have to worry about loads in
4688 -- this case, since these types have no signalling NaN's.
4690 if Vax_Float (Btyp) then
4691 Expand_Vax_Valid (N);
4693 -- The AAMP back end handles Valid for floating-point types
4695 elsif Is_AAMP_Float (Btyp) then
4696 Analyze_And_Resolve (Pref, Ptyp);
4697 Set_Etype (N, Standard_Boolean);
4700 -- Non VAX float case
4703 Find_Fat_Info (Ptyp, Ftp, Pkg);
4705 -- If the floating-point object might be unaligned, we need
4706 -- to call the special routine Unaligned_Valid, which makes
4707 -- the needed copy, being careful not to load the value into
4708 -- any floating-point register. The argument in this case is
4709 -- obj'Address (see Unaligned_Valid routine in Fat_Gen).
4711 if Is_Possibly_Unaligned_Object (Pref) then
4712 Expand_Fpt_Attribute
4713 (N, Pkg, Name_Unaligned_Valid,
4715 Make_Attribute_Reference (Loc,
4716 Prefix => Relocate_Node (Pref),
4717 Attribute_Name => Name_Address)));
4719 -- In the normal case where we are sure the object is
4720 -- aligned, we generate a call to Valid, and the argument in
4721 -- this case is obj'Unrestricted_Access (after converting
4722 -- obj to the right floating-point type).
4725 Expand_Fpt_Attribute
4726 (N, Pkg, Name_Valid,
4728 Make_Attribute_Reference (Loc,
4729 Prefix => Unchecked_Convert_To (Ftp, Pref),
4730 Attribute_Name => Name_Unrestricted_Access)));
4734 -- One more task, we still need a range check. Required
4735 -- only if we have a constraint, since the Valid routine
4736 -- catches infinities properly (infinities are never valid).
4738 -- The way we do the range check is simply to create the
4739 -- expression: Valid (N) and then Base_Type(Pref) in Typ.
4741 if not Subtypes_Statically_Match (Ptyp, Btyp) then
4744 Left_Opnd => Relocate_Node (N),
4747 Left_Opnd => Convert_To (Btyp, Pref),
4748 Right_Opnd => New_Occurrence_Of (Ptyp, Loc))));
4752 -- Enumeration type with holes
4754 -- For enumeration types with holes, the Pos value constructed by
4755 -- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a
4756 -- second argument of False returns minus one for an invalid value,
4757 -- and the non-negative pos value for a valid value, so the
4758 -- expansion of X'Valid is simply:
4760 -- type(X)'Pos (X) >= 0
4762 -- We can't quite generate it that way because of the requirement
4763 -- for the non-standard second argument of False in the resulting
4764 -- rep_to_pos call, so we have to explicitly create:
4766 -- _rep_to_pos (X, False) >= 0
4768 -- If we have an enumeration subtype, we also check that the
4769 -- value is in range:
4771 -- _rep_to_pos (X, False) >= 0
4773 -- (X >= type(X)'First and then type(X)'Last <= X)
4775 elsif Is_Enumeration_Type (Ptyp)
4776 and then Present (Enum_Pos_To_Rep (Base_Type (Ptyp)))
4781 Make_Function_Call (Loc,
4784 (TSS (Base_Type (Ptyp), TSS_Rep_To_Pos), Loc),
4785 Parameter_Associations => New_List (
4787 New_Occurrence_Of (Standard_False, Loc))),
4788 Right_Opnd => Make_Integer_Literal (Loc, 0));
4792 (Type_Low_Bound (Ptyp) /= Type_Low_Bound (Btyp)
4794 Type_High_Bound (Ptyp) /= Type_High_Bound (Btyp))
4796 -- The call to Make_Range_Test will create declarations
4797 -- that need a proper insertion point, but Pref is now
4798 -- attached to a node with no ancestor. Attach to tree
4799 -- even if it is to be rewritten below.
4801 Set_Parent (Tst, Parent (N));
4805 Left_Opnd => Make_Range_Test,
4811 -- Fortran convention booleans
4813 -- For the very special case of Fortran convention booleans, the
4814 -- value is always valid, since it is an integer with the semantics
4815 -- that non-zero is true, and any value is permissible.
4817 elsif Is_Boolean_Type (Ptyp)
4818 and then Convention (Ptyp) = Convention_Fortran
4820 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
4822 -- For biased representations, we will be doing an unchecked
4823 -- conversion without unbiasing the result. That means that the range
4824 -- test has to take this into account, and the proper form of the
4827 -- Btyp!(Pref) < Btyp!(Ptyp'Range_Length)
4829 elsif Has_Biased_Representation (Ptyp) then
4830 Btyp := RTE (RE_Unsigned_32);
4834 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
4836 Unchecked_Convert_To (Btyp,
4837 Make_Attribute_Reference (Loc,
4838 Prefix => New_Occurrence_Of (Ptyp, Loc),
4839 Attribute_Name => Name_Range_Length))));
4841 -- For all other scalar types, what we want logically is a
4844 -- X in type(X)'First .. type(X)'Last
4846 -- But that's precisely what won't work because of possible
4847 -- unwanted optimization (and indeed the basic motivation for
4848 -- the Valid attribute is exactly that this test does not work!)
4849 -- What will work is:
4851 -- Btyp!(X) >= Btyp!(type(X)'First)
4853 -- Btyp!(X) <= Btyp!(type(X)'Last)
4855 -- where Btyp is an integer type large enough to cover the full
4856 -- range of possible stored values (i.e. it is chosen on the basis
4857 -- of the size of the type, not the range of the values). We write
4858 -- this as two tests, rather than a range check, so that static
4859 -- evaluation will easily remove either or both of the checks if
4860 -- they can be -statically determined to be true (this happens
4861 -- when the type of X is static and the range extends to the full
4862 -- range of stored values).
4864 -- Unsigned types. Note: it is safe to consider only whether the
4865 -- subtype is unsigned, since we will in that case be doing all
4866 -- unsigned comparisons based on the subtype range. Since we use the
4867 -- actual subtype object size, this is appropriate.
4869 -- For example, if we have
4871 -- subtype x is integer range 1 .. 200;
4872 -- for x'Object_Size use 8;
4874 -- Now the base type is signed, but objects of this type are bits
4875 -- unsigned, and doing an unsigned test of the range 1 to 200 is
4876 -- correct, even though a value greater than 127 looks signed to a
4877 -- signed comparison.
4879 elsif Is_Unsigned_Type (Ptyp) then
4880 if Esize (Ptyp) <= 32 then
4881 Btyp := RTE (RE_Unsigned_32);
4883 Btyp := RTE (RE_Unsigned_64);
4886 Rewrite (N, Make_Range_Test);
4891 if Esize (Ptyp) <= Esize (Standard_Integer) then
4892 Btyp := Standard_Integer;
4894 Btyp := Universal_Integer;
4897 Rewrite (N, Make_Range_Test);
4900 Analyze_And_Resolve (N, Standard_Boolean);
4901 Validity_Checks_On := Save_Validity_Checks_On;
4908 -- Value attribute is handled in separate unti Exp_Imgv
4910 when Attribute_Value =>
4911 Exp_Imgv.Expand_Value_Attribute (N);
4917 -- The processing for Value_Size shares the processing for Size
4923 -- The processing for Version shares the processing for Body_Version
4929 -- Wide_Image attribute is handled in separate unit Exp_Imgv
4931 when Attribute_Wide_Image =>
4932 Exp_Imgv.Expand_Wide_Image_Attribute (N);
4934 ---------------------
4935 -- Wide_Wide_Image --
4936 ---------------------
4938 -- Wide_Wide_Image attribute is handled in separate unit Exp_Imgv
4940 when Attribute_Wide_Wide_Image =>
4941 Exp_Imgv.Expand_Wide_Wide_Image_Attribute (N);
4947 -- We expand typ'Wide_Value (X) into
4950 -- (Wide_String_To_String (X, Wide_Character_Encoding_Method))
4952 -- Wide_String_To_String is a runtime function that converts its wide
4953 -- string argument to String, converting any non-translatable characters
4954 -- into appropriate escape sequences. This preserves the required
4955 -- semantics of Wide_Value in all cases, and results in a very simple
4956 -- implementation approach.
4958 -- Note: for this approach to be fully standard compliant for the cases
4959 -- where typ is Wide_Character and Wide_Wide_Character, the encoding
4960 -- method must cover the entire character range (e.g. UTF-8). But that
4961 -- is a reasonable requirement when dealing with encoded character
4962 -- sequences. Presumably if one of the restrictive encoding mechanisms
4963 -- is in use such as Shift-JIS, then characters that cannot be
4964 -- represented using this encoding will not appear in any case.
4966 when Attribute_Wide_Value => Wide_Value :
4969 Make_Attribute_Reference (Loc,
4971 Attribute_Name => Name_Value,
4973 Expressions => New_List (
4974 Make_Function_Call (Loc,
4976 New_Reference_To (RTE (RE_Wide_String_To_String), Loc),
4978 Parameter_Associations => New_List (
4979 Relocate_Node (First (Exprs)),
4980 Make_Integer_Literal (Loc,
4981 Intval => Int (Wide_Character_Encoding_Method)))))));
4983 Analyze_And_Resolve (N, Typ);
4986 ---------------------
4987 -- Wide_Wide_Value --
4988 ---------------------
4990 -- We expand typ'Wide_Value_Value (X) into
4993 -- (Wide_Wide_String_To_String (X, Wide_Character_Encoding_Method))
4995 -- Wide_Wide_String_To_String is a runtime function that converts its
4996 -- wide string argument to String, converting any non-translatable
4997 -- characters into appropriate escape sequences. This preserves the
4998 -- required semantics of Wide_Wide_Value in all cases, and results in a
4999 -- very simple implementation approach.
5001 -- It's not quite right where typ = Wide_Wide_Character, because the
5002 -- encoding method may not cover the whole character type ???
5004 when Attribute_Wide_Wide_Value => Wide_Wide_Value :
5007 Make_Attribute_Reference (Loc,
5009 Attribute_Name => Name_Value,
5011 Expressions => New_List (
5012 Make_Function_Call (Loc,
5014 New_Reference_To (RTE (RE_Wide_Wide_String_To_String), Loc),
5016 Parameter_Associations => New_List (
5017 Relocate_Node (First (Exprs)),
5018 Make_Integer_Literal (Loc,
5019 Intval => Int (Wide_Character_Encoding_Method)))))));
5021 Analyze_And_Resolve (N, Typ);
5022 end Wide_Wide_Value;
5024 ---------------------
5025 -- Wide_Wide_Width --
5026 ---------------------
5028 -- Wide_Wide_Width attribute is handled in separate unit Exp_Imgv
5030 when Attribute_Wide_Wide_Width =>
5031 Exp_Imgv.Expand_Width_Attribute (N, Wide_Wide);
5037 -- Wide_Width attribute is handled in separate unit Exp_Imgv
5039 when Attribute_Wide_Width =>
5040 Exp_Imgv.Expand_Width_Attribute (N, Wide);
5046 -- Width attribute is handled in separate unit Exp_Imgv
5048 when Attribute_Width =>
5049 Exp_Imgv.Expand_Width_Attribute (N, Normal);
5055 when Attribute_Write => Write : declare
5056 P_Type : constant Entity_Id := Entity (Pref);
5057 U_Type : constant Entity_Id := Underlying_Type (P_Type);
5065 -- If no underlying type, we have an error that will be diagnosed
5066 -- elsewhere, so here we just completely ignore the expansion.
5072 -- The simple case, if there is a TSS for Write, just call it
5074 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Write);
5076 if Present (Pname) then
5080 -- If there is a Stream_Convert pragma, use it, we rewrite
5082 -- sourcetyp'Output (stream, Item)
5086 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
5088 -- where strmwrite is the given Write function that converts an
5089 -- argument of type sourcetyp or a type acctyp, from which it is
5090 -- derived to type strmtyp. The conversion to acttyp is required
5091 -- for the derived case.
5093 Prag := Get_Stream_Convert_Pragma (P_Type);
5095 if Present (Prag) then
5097 Next (Next (First (Pragma_Argument_Associations (Prag))));
5098 Wfunc := Entity (Expression (Arg3));
5101 Make_Attribute_Reference (Loc,
5102 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
5103 Attribute_Name => Name_Output,
5104 Expressions => New_List (
5105 Relocate_Node (First (Exprs)),
5106 Make_Function_Call (Loc,
5107 Name => New_Occurrence_Of (Wfunc, Loc),
5108 Parameter_Associations => New_List (
5109 OK_Convert_To (Etype (First_Formal (Wfunc)),
5110 Relocate_Node (Next (First (Exprs)))))))));
5115 -- For elementary types, we call the W_xxx routine directly
5117 elsif Is_Elementary_Type (U_Type) then
5118 Rewrite (N, Build_Elementary_Write_Call (N));
5124 elsif Is_Array_Type (U_Type) then
5125 Build_Array_Write_Procedure (N, U_Type, Decl, Pname);
5126 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
5128 -- Tagged type case, use the primitive Write function. Note that
5129 -- this will dispatch in the class-wide case which is what we want
5131 elsif Is_Tagged_Type (U_Type) then
5132 Pname := Find_Prim_Op (U_Type, TSS_Stream_Write);
5134 -- All other record type cases, including protected records.
5135 -- The latter only arise for expander generated code for
5136 -- handling shared passive partition access.
5140 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
5142 -- Ada 2005 (AI-216): Program_Error is raised when executing
5143 -- the default implementation of the Write attribute of an
5144 -- Unchecked_Union type. However, if the 'Write reference is
5145 -- within the generated Output stream procedure, Write outputs
5146 -- the components, and the default values of the discriminant
5147 -- are streamed by the Output procedure itself.
5149 if Is_Unchecked_Union (Base_Type (U_Type))
5150 and not Is_TSS (Current_Scope, TSS_Stream_Output)
5153 Make_Raise_Program_Error (Loc,
5154 Reason => PE_Unchecked_Union_Restriction));
5157 if Has_Discriminants (U_Type)
5159 (Discriminant_Default_Value (First_Discriminant (U_Type)))
5161 Build_Mutable_Record_Write_Procedure
5162 (Loc, Base_Type (U_Type), Decl, Pname);
5164 Build_Record_Write_Procedure
5165 (Loc, Base_Type (U_Type), Decl, Pname);
5168 Insert_Action (N, Decl);
5172 -- If we fall through, Pname is the procedure to be called
5174 Rewrite_Stream_Proc_Call (Pname);
5177 -- Component_Size is handled by the back end, unless the component size
5178 -- is known at compile time, which is always true in the packed array
5179 -- case. It is important that the packed array case is handled in the
5180 -- front end (see Eval_Attribute) since the back end would otherwise get
5181 -- confused by the equivalent packed array type.
5183 when Attribute_Component_Size =>
5186 -- The following attributes are handled by the back end (except that
5187 -- static cases have already been evaluated during semantic processing,
5188 -- but in any case the back end should not count on this). The one bit
5189 -- of special processing required is that these attributes typically
5190 -- generate conditionals in the code, so we need to check the relevant
5193 when Attribute_Max |
5195 Check_Restriction (No_Implicit_Conditionals, N);
5197 -- The following attributes are handled by the back end (except that
5198 -- static cases have already been evaluated during semantic processing,
5199 -- but in any case the back end should not count on this).
5201 -- The back end also handles the non-class-wide cases of Size
5203 when Attribute_Bit_Order |
5204 Attribute_Code_Address |
5205 Attribute_Definite |
5206 Attribute_Null_Parameter |
5207 Attribute_Passed_By_Reference |
5208 Attribute_Pool_Address =>
5211 -- The following attributes are also handled by the back end, but return
5212 -- a universal integer result, so may need a conversion for checking
5213 -- that the result is in range.
5215 when Attribute_Aft |
5217 Attribute_Max_Size_In_Storage_Elements
5219 Apply_Universal_Integer_Attribute_Checks (N);
5221 -- The following attributes should not appear at this stage, since they
5222 -- have already been handled by the analyzer (and properly rewritten
5223 -- with corresponding values or entities to represent the right values)
5225 when Attribute_Abort_Signal |
5226 Attribute_Address_Size |
5229 Attribute_Default_Bit_Order |
5236 Attribute_Fast_Math |
5237 Attribute_Has_Access_Values |
5238 Attribute_Has_Discriminants |
5239 Attribute_Has_Tagged_Values |
5241 Attribute_Machine_Emax |
5242 Attribute_Machine_Emin |
5243 Attribute_Machine_Mantissa |
5244 Attribute_Machine_Overflows |
5245 Attribute_Machine_Radix |
5246 Attribute_Machine_Rounds |
5247 Attribute_Maximum_Alignment |
5248 Attribute_Model_Emin |
5249 Attribute_Model_Epsilon |
5250 Attribute_Model_Mantissa |
5251 Attribute_Model_Small |
5253 Attribute_Partition_ID |
5255 Attribute_Safe_Emax |
5256 Attribute_Safe_First |
5257 Attribute_Safe_Large |
5258 Attribute_Safe_Last |
5259 Attribute_Safe_Small |
5261 Attribute_Signed_Zeros |
5263 Attribute_Storage_Unit |
5264 Attribute_Stub_Type |
5265 Attribute_Target_Name |
5266 Attribute_Type_Class |
5267 Attribute_Unconstrained_Array |
5268 Attribute_Universal_Literal_String |
5269 Attribute_Wchar_T_Size |
5270 Attribute_Word_Size =>
5272 raise Program_Error;
5274 -- The Asm_Input and Asm_Output attributes are not expanded at this
5275 -- stage, but will be eliminated in the expansion of the Asm call, see
5276 -- Exp_Intr for details. So the back end will never see these either.
5278 when Attribute_Asm_Input |
5279 Attribute_Asm_Output =>
5286 when RE_Not_Available =>
5288 end Expand_N_Attribute_Reference;
5290 ----------------------
5291 -- Expand_Pred_Succ --
5292 ----------------------
5294 -- For typ'Pred (exp), we generate the check
5296 -- [constraint_error when exp = typ'Base'First]
5298 -- Similarly, for typ'Succ (exp), we generate the check
5300 -- [constraint_error when exp = typ'Base'Last]
5302 -- These checks are not generated for modular types, since the proper
5303 -- semantics for Succ and Pred on modular types is to wrap, not raise CE.
5305 procedure Expand_Pred_Succ (N : Node_Id) is
5306 Loc : constant Source_Ptr := Sloc (N);
5310 if Attribute_Name (N) = Name_Pred then
5317 Make_Raise_Constraint_Error (Loc,
5321 Duplicate_Subexpr_Move_Checks (First (Expressions (N))),
5323 Make_Attribute_Reference (Loc,
5325 New_Reference_To (Base_Type (Etype (Prefix (N))), Loc),
5326 Attribute_Name => Cnam)),
5327 Reason => CE_Overflow_Check_Failed));
5328 end Expand_Pred_Succ;
5334 procedure Find_Fat_Info
5336 Fat_Type : out Entity_Id;
5337 Fat_Pkg : out RE_Id)
5339 Btyp : constant Entity_Id := Base_Type (T);
5340 Rtyp : constant Entity_Id := Root_Type (T);
5341 Digs : constant Nat := UI_To_Int (Digits_Value (Btyp));
5344 -- If the base type is VAX float, then get appropriate VAX float type
5346 if Vax_Float (Btyp) then
5349 Fat_Type := RTE (RE_Fat_VAX_F);
5350 Fat_Pkg := RE_Attr_VAX_F_Float;
5353 Fat_Type := RTE (RE_Fat_VAX_D);
5354 Fat_Pkg := RE_Attr_VAX_D_Float;
5357 Fat_Type := RTE (RE_Fat_VAX_G);
5358 Fat_Pkg := RE_Attr_VAX_G_Float;
5361 raise Program_Error;
5364 -- If root type is VAX float, this is the case where the library has
5365 -- been recompiled in VAX float mode, and we have an IEEE float type.
5366 -- This is when we use the special IEEE Fat packages.
5368 elsif Vax_Float (Rtyp) then
5371 Fat_Type := RTE (RE_Fat_IEEE_Short);
5372 Fat_Pkg := RE_Attr_IEEE_Short;
5375 Fat_Type := RTE (RE_Fat_IEEE_Long);
5376 Fat_Pkg := RE_Attr_IEEE_Long;
5379 raise Program_Error;
5382 -- If neither the base type nor the root type is VAX_Float then VAX
5383 -- float is out of the picture, and we can just use the root type.
5388 if Fat_Type = Standard_Short_Float then
5389 Fat_Pkg := RE_Attr_Short_Float;
5391 elsif Fat_Type = Standard_Float then
5392 Fat_Pkg := RE_Attr_Float;
5394 elsif Fat_Type = Standard_Long_Float then
5395 Fat_Pkg := RE_Attr_Long_Float;
5397 elsif Fat_Type = Standard_Long_Long_Float then
5398 Fat_Pkg := RE_Attr_Long_Long_Float;
5400 -- Universal real (which is its own root type) is treated as being
5401 -- equivalent to Standard.Long_Long_Float, since it is defined to
5402 -- have the same precision as the longest Float type.
5404 elsif Fat_Type = Universal_Real then
5405 Fat_Type := Standard_Long_Long_Float;
5406 Fat_Pkg := RE_Attr_Long_Long_Float;
5409 raise Program_Error;
5414 ----------------------------
5415 -- Find_Stream_Subprogram --
5416 ----------------------------
5418 function Find_Stream_Subprogram
5420 Nam : TSS_Name_Type) return Entity_Id
5422 Base_Typ : constant Entity_Id := Base_Type (Typ);
5423 Ent : constant Entity_Id := TSS (Typ, Nam);
5426 if Present (Ent) then
5430 -- Stream attributes for strings are expanded into library calls. The
5431 -- following checks are disabled when the run-time is not available or
5432 -- when compiling predefined types due to bootstrap issues. As a result,
5433 -- the compiler will generate in-place stream routines for string types
5434 -- that appear in GNAT's library, but will generate calls via rtsfind
5435 -- to library routines for user code.
5436 -- ??? For now, disable this code for JVM, since this generates a
5437 -- VerifyError exception at run-time on e.g. c330001.
5438 -- This is disabled for AAMP, to avoid making dependences on files not
5439 -- supported in the AAMP library (such as s-fileio.adb).
5441 if VM_Target /= JVM_Target
5442 and then not AAMP_On_Target
5444 not Is_Predefined_File_Name (Unit_File_Name (Current_Sem_Unit))
5446 -- String as defined in package Ada
5448 if Base_Typ = Standard_String then
5449 if Restriction_Active (No_Stream_Optimizations) then
5450 if Nam = TSS_Stream_Input then
5451 return RTE (RE_String_Input);
5453 elsif Nam = TSS_Stream_Output then
5454 return RTE (RE_String_Output);
5456 elsif Nam = TSS_Stream_Read then
5457 return RTE (RE_String_Read);
5459 else pragma Assert (Nam = TSS_Stream_Write);
5460 return RTE (RE_String_Write);
5464 if Nam = TSS_Stream_Input then
5465 return RTE (RE_String_Input_Blk_IO);
5467 elsif Nam = TSS_Stream_Output then
5468 return RTE (RE_String_Output_Blk_IO);
5470 elsif Nam = TSS_Stream_Read then
5471 return RTE (RE_String_Read_Blk_IO);
5473 else pragma Assert (Nam = TSS_Stream_Write);
5474 return RTE (RE_String_Write_Blk_IO);
5478 -- Wide_String as defined in package Ada
5480 elsif Base_Typ = Standard_Wide_String then
5481 if Restriction_Active (No_Stream_Optimizations) then
5482 if Nam = TSS_Stream_Input then
5483 return RTE (RE_Wide_String_Input);
5485 elsif Nam = TSS_Stream_Output then
5486 return RTE (RE_Wide_String_Output);
5488 elsif Nam = TSS_Stream_Read then
5489 return RTE (RE_Wide_String_Read);
5491 else pragma Assert (Nam = TSS_Stream_Write);
5492 return RTE (RE_Wide_String_Write);
5496 if Nam = TSS_Stream_Input then
5497 return RTE (RE_Wide_String_Input_Blk_IO);
5499 elsif Nam = TSS_Stream_Output then
5500 return RTE (RE_Wide_String_Output_Blk_IO);
5502 elsif Nam = TSS_Stream_Read then
5503 return RTE (RE_Wide_String_Read_Blk_IO);
5505 else pragma Assert (Nam = TSS_Stream_Write);
5506 return RTE (RE_Wide_String_Write_Blk_IO);
5510 -- Wide_Wide_String as defined in package Ada
5512 elsif Base_Typ = Standard_Wide_Wide_String then
5513 if Restriction_Active (No_Stream_Optimizations) then
5514 if Nam = TSS_Stream_Input then
5515 return RTE (RE_Wide_Wide_String_Input);
5517 elsif Nam = TSS_Stream_Output then
5518 return RTE (RE_Wide_Wide_String_Output);
5520 elsif Nam = TSS_Stream_Read then
5521 return RTE (RE_Wide_Wide_String_Read);
5523 else pragma Assert (Nam = TSS_Stream_Write);
5524 return RTE (RE_Wide_Wide_String_Write);
5528 if Nam = TSS_Stream_Input then
5529 return RTE (RE_Wide_Wide_String_Input_Blk_IO);
5531 elsif Nam = TSS_Stream_Output then
5532 return RTE (RE_Wide_Wide_String_Output_Blk_IO);
5534 elsif Nam = TSS_Stream_Read then
5535 return RTE (RE_Wide_Wide_String_Read_Blk_IO);
5537 else pragma Assert (Nam = TSS_Stream_Write);
5538 return RTE (RE_Wide_Wide_String_Write_Blk_IO);
5544 if Is_Tagged_Type (Typ)
5545 and then Is_Derived_Type (Typ)
5547 return Find_Prim_Op (Typ, Nam);
5549 return Find_Inherited_TSS (Typ, Nam);
5551 end Find_Stream_Subprogram;
5553 -----------------------
5554 -- Get_Index_Subtype --
5555 -----------------------
5557 function Get_Index_Subtype (N : Node_Id) return Node_Id is
5558 P_Type : Entity_Id := Etype (Prefix (N));
5563 if Is_Access_Type (P_Type) then
5564 P_Type := Designated_Type (P_Type);
5567 if No (Expressions (N)) then
5570 J := UI_To_Int (Expr_Value (First (Expressions (N))));
5573 Indx := First_Index (P_Type);
5579 return Etype (Indx);
5580 end Get_Index_Subtype;
5582 -------------------------------
5583 -- Get_Stream_Convert_Pragma --
5584 -------------------------------
5586 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id is
5591 -- Note: we cannot use Get_Rep_Pragma here because of the peculiarity
5592 -- that a stream convert pragma for a tagged type is not inherited from
5593 -- its parent. Probably what is wrong here is that it is basically
5594 -- incorrect to consider a stream convert pragma to be a representation
5595 -- pragma at all ???
5597 N := First_Rep_Item (Implementation_Base_Type (T));
5598 while Present (N) loop
5599 if Nkind (N) = N_Pragma
5600 and then Pragma_Name (N) = Name_Stream_Convert
5602 -- For tagged types this pragma is not inherited, so we
5603 -- must verify that it is defined for the given type and
5607 Entity (Expression (First (Pragma_Argument_Associations (N))));
5609 if not Is_Tagged_Type (T)
5611 or else (Is_Private_Type (Typ) and then T = Full_View (Typ))
5621 end Get_Stream_Convert_Pragma;
5623 ---------------------------------
5624 -- Is_Constrained_Packed_Array --
5625 ---------------------------------
5627 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean is
5628 Arr : Entity_Id := Typ;
5631 if Is_Access_Type (Arr) then
5632 Arr := Designated_Type (Arr);
5635 return Is_Array_Type (Arr)
5636 and then Is_Constrained (Arr)
5637 and then Present (Packed_Array_Type (Arr));
5638 end Is_Constrained_Packed_Array;
5640 ----------------------------------------
5641 -- Is_Inline_Floating_Point_Attribute --
5642 ----------------------------------------
5644 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean is
5645 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
5648 if Nkind (Parent (N)) /= N_Type_Conversion
5649 or else not Is_Integer_Type (Etype (Parent (N)))
5654 -- Should also support 'Machine_Rounding and 'Unbiased_Rounding, but
5655 -- required back end support has not been implemented yet ???
5657 return Id = Attribute_Truncation;
5658 end Is_Inline_Floating_Point_Attribute;
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