1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
18 -- You should have received a copy of the GNU General Public License along --
19 -- with this program; see file COPYING3. If not see --
20 -- <http://www.gnu.org/licenses/>. --
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_Aux; use Sem_Aux;
57 with Sem_Ch6; use Sem_Ch6;
58 with Sem_Ch7; use Sem_Ch7;
59 with Sem_Ch8; use Sem_Ch8;
60 with Sem_Eval; use Sem_Eval;
61 with Sem_Res; use Sem_Res;
62 with Sem_Util; use Sem_Util;
63 with Sinfo; use Sinfo;
64 with Snames; use Snames;
65 with Stand; use Stand;
66 with Stringt; use Stringt;
67 with Targparm; use Targparm;
68 with Tbuild; use Tbuild;
69 with Ttypes; use Ttypes;
70 with Uintp; use Uintp;
71 with Uname; use Uname;
72 with Validsw; use Validsw;
74 package body Exp_Attr is
76 -----------------------
77 -- Local Subprograms --
78 -----------------------
80 procedure Compile_Stream_Body_In_Scope
85 -- The body for a stream subprogram may be generated outside of the scope
86 -- of the type. If the type is fully private, it may depend on the full
87 -- view of other types (e.g. indices) that are currently private as well.
88 -- We install the declarations of the package in which the type is declared
89 -- before compiling the body in what is its proper environment. The Check
90 -- parameter indicates if checks are to be suppressed for the stream body.
91 -- We suppress checks for array/record reads, since the rule is that these
92 -- are like assignments, out of range values due to uninitialized storage,
93 -- or other invalid values do NOT cause a Constraint_Error to be raised.
95 procedure Expand_Access_To_Protected_Op
100 -- An attribute reference to a protected subprogram is transformed into
101 -- a pair of pointers: one to the object, and one to the operations.
102 -- This expansion is performed for 'Access and for 'Unrestricted_Access.
104 procedure Expand_Fpt_Attribute
109 -- This procedure expands a call to a floating-point attribute function.
110 -- N is the attribute reference node, and Args is a list of arguments to
111 -- be passed to the function call. Pkg identifies the package containing
112 -- the appropriate instantiation of System.Fat_Gen. Float arguments in Args
113 -- have already been converted to the floating-point type for which Pkg was
114 -- instantiated. The Nam argument is the relevant attribute processing
115 -- routine to be called. This is the same as the attribute name, except in
116 -- the Unaligned_Valid case.
118 procedure Expand_Fpt_Attribute_R (N : Node_Id);
119 -- This procedure expands a call to a floating-point attribute function
120 -- that takes a single floating-point argument. The function to be called
121 -- is always the same as the attribute name.
123 procedure Expand_Fpt_Attribute_RI (N : Node_Id);
124 -- This procedure expands a call to a floating-point attribute function
125 -- that takes one floating-point argument and one integer argument. The
126 -- function to be called is always the same as the attribute name.
128 procedure Expand_Fpt_Attribute_RR (N : Node_Id);
129 -- This procedure expands a call to a floating-point attribute function
130 -- that takes two floating-point arguments. The function to be called
131 -- is always the same as the attribute name.
133 procedure Expand_Pred_Succ (N : Node_Id);
134 -- Handles expansion of Pred or Succ attributes for case of non-real
135 -- operand with overflow checking required.
137 function Get_Index_Subtype (N : Node_Id) return Entity_Id;
138 -- Used for Last, Last, and Length, when the prefix is an array type.
139 -- Obtains the corresponding index subtype.
141 procedure Find_Fat_Info
143 Fat_Type : out Entity_Id;
144 Fat_Pkg : out RE_Id);
145 -- Given a floating-point type T, identifies the package containing the
146 -- attributes for this type (returned in Fat_Pkg), and the corresponding
147 -- type for which this package was instantiated from Fat_Gen. Error if T
148 -- is not a floating-point type.
150 function Find_Stream_Subprogram
152 Nam : TSS_Name_Type) return Entity_Id;
153 -- Returns the stream-oriented subprogram attribute for Typ. For tagged
154 -- types, the corresponding primitive operation is looked up, else the
155 -- appropriate TSS from the type itself, or from its closest ancestor
156 -- defining it, is returned. In both cases, inheritance of representation
157 -- aspects is thus taken into account.
159 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id;
160 -- Given a type, find a corresponding stream convert pragma that applies to
161 -- the implementation base type of this type (Typ). If found, return the
162 -- pragma node, otherwise return Empty if no pragma is found.
164 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean;
165 -- Utility for array attributes, returns true on packed constrained
166 -- arrays, and on access to same.
168 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean;
169 -- Returns true iff the given node refers to an attribute call that
170 -- can be expanded directly by the back end and does not need front end
171 -- expansion. Typically used for rounding and truncation attributes that
172 -- appear directly inside a conversion to integer.
174 ----------------------------------
175 -- Compile_Stream_Body_In_Scope --
176 ----------------------------------
178 procedure Compile_Stream_Body_In_Scope
184 Installed : Boolean := False;
185 Scop : constant Entity_Id := Scope (Arr);
186 Curr : constant Entity_Id := Current_Scope;
190 and then not In_Open_Scopes (Scop)
191 and then Ekind (Scop) = E_Package
194 Install_Visible_Declarations (Scop);
195 Install_Private_Declarations (Scop);
198 -- The entities in the package are now visible, but the generated
199 -- stream entity must appear in the current scope (usually an
200 -- enclosing stream function) so that itypes all have their proper
207 Insert_Action (N, Decl);
209 Insert_Action (N, Decl, Suppress => All_Checks);
214 -- Remove extra copy of current scope, and package itself
217 End_Package_Scope (Scop);
219 end Compile_Stream_Body_In_Scope;
221 -----------------------------------
222 -- Expand_Access_To_Protected_Op --
223 -----------------------------------
225 procedure Expand_Access_To_Protected_Op
230 -- The value of the attribute_reference is a record containing two
231 -- fields: an access to the protected object, and an access to the
232 -- subprogram itself. The prefix is a selected component.
234 Loc : constant Source_Ptr := Sloc (N);
236 Btyp : constant Entity_Id := Base_Type (Typ);
238 E_T : constant Entity_Id := Equivalent_Type (Btyp);
239 Acc : constant Entity_Id :=
240 Etype (Next_Component (First_Component (E_T)));
244 function May_Be_External_Call return Boolean;
245 -- If the 'Access is to a local operation, but appears in a context
246 -- where it may lead to a call from outside the object, we must treat
247 -- this as an external call. Clearly we cannot tell without full
248 -- flow analysis, and a subsequent call that uses this 'Access may
249 -- lead to a bounded error (trying to seize locks twice, e.g.). For
250 -- now we treat 'Access as a potential external call if it is an actual
251 -- in a call to an outside subprogram.
253 --------------------------
254 -- May_Be_External_Call --
255 --------------------------
257 function May_Be_External_Call return Boolean is
259 Par : Node_Id := Parent (N);
262 -- Account for the case where the Access attribute is part of a
263 -- named parameter association.
265 if Nkind (Par) = N_Parameter_Association then
269 if Nkind_In (Par, N_Procedure_Call_Statement, N_Function_Call)
270 and then Is_Entity_Name (Name (Par))
272 Subp := Entity (Name (Par));
273 return not In_Open_Scopes (Scope (Subp));
277 end May_Be_External_Call;
279 -- Start of processing for Expand_Access_To_Protected_Op
282 -- Within the body of the protected type, the prefix
283 -- designates a local operation, and the object is the first
284 -- parameter of the corresponding protected body of the
285 -- current enclosing operation.
287 if Is_Entity_Name (Pref) then
288 if May_Be_External_Call then
291 (External_Subprogram (Entity (Pref)), Loc);
295 (Protected_Body_Subprogram (Entity (Pref)), Loc);
298 -- Don't traverse the scopes when the attribute occurs within an init
299 -- proc, because we directly use the _init formal of the init proc in
302 Curr := Current_Scope;
303 if not Is_Init_Proc (Curr) then
304 pragma Assert (In_Open_Scopes (Scope (Entity (Pref))));
306 while Scope (Curr) /= Scope (Entity (Pref)) loop
307 Curr := Scope (Curr);
311 -- In case of protected entries the first formal of its Protected_
312 -- Body_Subprogram is the address of the object.
314 if Ekind (Curr) = E_Entry then
318 (Protected_Body_Subprogram (Curr)), Loc);
320 -- If the current scope is an init proc, then use the address of the
321 -- _init formal as the object reference.
323 elsif Is_Init_Proc (Curr) then
325 Make_Attribute_Reference (Loc,
326 Prefix => New_Occurrence_Of (First_Formal (Curr), Loc),
327 Attribute_Name => Name_Address);
329 -- In case of protected subprograms the first formal of its
330 -- Protected_Body_Subprogram is the object and we get its address.
334 Make_Attribute_Reference (Loc,
338 (Protected_Body_Subprogram (Curr)), Loc),
339 Attribute_Name => Name_Address);
342 -- Case where the prefix is not an entity name. Find the
343 -- version of the protected operation to be called from
344 -- outside the protected object.
350 (Entity (Selector_Name (Pref))), Loc);
353 Make_Attribute_Reference (Loc,
354 Prefix => Relocate_Node (Prefix (Pref)),
355 Attribute_Name => Name_Address);
363 Unchecked_Convert_To (Acc,
364 Make_Attribute_Reference (Loc,
366 Attribute_Name => Name_Address))));
370 Analyze_And_Resolve (N, E_T);
372 -- For subsequent analysis, the node must retain its type.
373 -- The backend will replace it with the equivalent type where
377 end Expand_Access_To_Protected_Op;
379 --------------------------
380 -- Expand_Fpt_Attribute --
381 --------------------------
383 procedure Expand_Fpt_Attribute
389 Loc : constant Source_Ptr := Sloc (N);
390 Typ : constant Entity_Id := Etype (N);
394 -- The function name is the selected component Attr_xxx.yyy where
395 -- Attr_xxx is the package name, and yyy is the argument Nam.
397 -- Note: it would be more usual to have separate RE entries for each
398 -- of the entities in the Fat packages, but first they have identical
399 -- names (so we would have to have lots of renaming declarations to
400 -- meet the normal RE rule of separate names for all runtime entities),
401 -- and second there would be an awful lot of them!
404 Make_Selected_Component (Loc,
405 Prefix => New_Reference_To (RTE (Pkg), Loc),
406 Selector_Name => Make_Identifier (Loc, Nam));
408 -- The generated call is given the provided set of parameters, and then
409 -- wrapped in a conversion which converts the result to the target type
410 -- We use the base type as the target because a range check may be
414 Unchecked_Convert_To (Base_Type (Etype (N)),
415 Make_Function_Call (Loc,
417 Parameter_Associations => Args)));
419 Analyze_And_Resolve (N, Typ);
420 end Expand_Fpt_Attribute;
422 ----------------------------
423 -- Expand_Fpt_Attribute_R --
424 ----------------------------
426 -- The single argument is converted to its root type to call the
427 -- appropriate runtime function, with the actual call being built
428 -- by Expand_Fpt_Attribute
430 procedure Expand_Fpt_Attribute_R (N : Node_Id) is
431 E1 : constant Node_Id := First (Expressions (N));
435 Find_Fat_Info (Etype (E1), Ftp, Pkg);
437 (N, Pkg, Attribute_Name (N),
438 New_List (Unchecked_Convert_To (Ftp, Relocate_Node (E1))));
439 end Expand_Fpt_Attribute_R;
441 -----------------------------
442 -- Expand_Fpt_Attribute_RI --
443 -----------------------------
445 -- The first argument is converted to its root type and the second
446 -- argument is converted to standard long long integer to call the
447 -- appropriate runtime function, with the actual call being built
448 -- by Expand_Fpt_Attribute
450 procedure Expand_Fpt_Attribute_RI (N : Node_Id) is
451 E1 : constant Node_Id := First (Expressions (N));
454 E2 : constant Node_Id := Next (E1);
456 Find_Fat_Info (Etype (E1), Ftp, Pkg);
458 (N, Pkg, Attribute_Name (N),
460 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
461 Unchecked_Convert_To (Standard_Integer, Relocate_Node (E2))));
462 end Expand_Fpt_Attribute_RI;
464 -----------------------------
465 -- Expand_Fpt_Attribute_RR --
466 -----------------------------
468 -- The two arguments are converted to their root types to call the
469 -- appropriate runtime function, with the actual call being built
470 -- by Expand_Fpt_Attribute
472 procedure Expand_Fpt_Attribute_RR (N : Node_Id) is
473 E1 : constant Node_Id := First (Expressions (N));
476 E2 : constant Node_Id := Next (E1);
478 Find_Fat_Info (Etype (E1), Ftp, Pkg);
480 (N, Pkg, Attribute_Name (N),
482 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
483 Unchecked_Convert_To (Ftp, Relocate_Node (E2))));
484 end Expand_Fpt_Attribute_RR;
486 ----------------------------------
487 -- Expand_N_Attribute_Reference --
488 ----------------------------------
490 procedure Expand_N_Attribute_Reference (N : Node_Id) is
491 Loc : constant Source_Ptr := Sloc (N);
492 Typ : constant Entity_Id := Etype (N);
493 Btyp : constant Entity_Id := Base_Type (Typ);
494 Pref : constant Node_Id := Prefix (N);
495 Ptyp : constant Entity_Id := Etype (Pref);
496 Exprs : constant List_Id := Expressions (N);
497 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
499 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id);
500 -- Rewrites a stream attribute for Read, Write or Output with the
501 -- procedure call. Pname is the entity for the procedure to call.
503 ------------------------------
504 -- Rewrite_Stream_Proc_Call --
505 ------------------------------
507 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id) is
508 Item : constant Node_Id := Next (First (Exprs));
509 Formal : constant Entity_Id := Next_Formal (First_Formal (Pname));
510 Formal_Typ : constant Entity_Id := Etype (Formal);
511 Is_Written : constant Boolean := (Ekind (Formal) /= E_In_Parameter);
514 -- The expansion depends on Item, the second actual, which is
515 -- the object being streamed in or out.
517 -- If the item is a component of a packed array type, and
518 -- a conversion is needed on exit, we introduce a temporary to
519 -- hold the value, because otherwise the packed reference will
520 -- not be properly expanded.
522 if Nkind (Item) = N_Indexed_Component
523 and then Is_Packed (Base_Type (Etype (Prefix (Item))))
524 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
528 Temp : constant Entity_Id :=
529 Make_Defining_Identifier
530 (Loc, New_Internal_Name ('V'));
536 Make_Object_Declaration (Loc,
537 Defining_Identifier => Temp,
539 New_Occurrence_Of (Formal_Typ, Loc));
540 Set_Etype (Temp, Formal_Typ);
543 Make_Assignment_Statement (Loc,
544 Name => New_Copy_Tree (Item),
547 (Etype (Item), New_Occurrence_Of (Temp, Loc)));
549 Rewrite (Item, New_Occurrence_Of (Temp, Loc));
553 Make_Procedure_Call_Statement (Loc,
554 Name => New_Occurrence_Of (Pname, Loc),
555 Parameter_Associations => Exprs),
558 Rewrite (N, Make_Null_Statement (Loc));
563 -- For the class-wide dispatching cases, and for cases in which
564 -- the base type of the second argument matches the base type of
565 -- the corresponding formal parameter (that is to say the stream
566 -- operation is not inherited), we are all set, and can use the
567 -- argument unchanged.
569 -- For all other cases we do an unchecked conversion of the second
570 -- parameter to the type of the formal of the procedure we are
571 -- calling. This deals with the private type cases, and with going
572 -- to the root type as required in elementary type case.
574 if not Is_Class_Wide_Type (Entity (Pref))
575 and then not Is_Class_Wide_Type (Etype (Item))
576 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
579 Unchecked_Convert_To (Formal_Typ, Relocate_Node (Item)));
581 -- For untagged derived types set Assignment_OK, to prevent
582 -- copies from being created when the unchecked conversion
583 -- is expanded (which would happen in Remove_Side_Effects
584 -- if Expand_N_Unchecked_Conversion were allowed to call
585 -- Force_Evaluation). The copy could violate Ada semantics
586 -- in cases such as an actual that is an out parameter.
587 -- Note that this approach is also used in exp_ch7 for calls
588 -- to controlled type operations to prevent problems with
589 -- actuals wrapped in unchecked conversions.
591 if Is_Untagged_Derivation (Etype (Expression (Item))) then
592 Set_Assignment_OK (Item);
596 -- And now rewrite the call
599 Make_Procedure_Call_Statement (Loc,
600 Name => New_Occurrence_Of (Pname, Loc),
601 Parameter_Associations => Exprs));
604 end Rewrite_Stream_Proc_Call;
606 -- Start of processing for Expand_N_Attribute_Reference
609 -- Do required validity checking, if enabled. Do not apply check to
610 -- output parameters of an Asm instruction, since the value of this
611 -- is not set till after the attribute has been elaborated, and do
612 -- not apply the check to the arguments of a 'Read or 'Input attribute
613 -- reference since the scalar argument is an OUT scalar.
615 if Validity_Checks_On and then Validity_Check_Operands
616 and then Id /= Attribute_Asm_Output
617 and then Id /= Attribute_Read
618 and then Id /= Attribute_Input
623 Expr := First (Expressions (N));
624 while Present (Expr) loop
631 -- Ada 2005 (AI-318-02): If attribute prefix is a call to a build-in-
632 -- place function, then a temporary return object needs to be created
633 -- and access to it must be passed to the function. Currently we limit
634 -- such functions to those with inherently limited result subtypes, but
635 -- eventually we plan to expand the functions that are treated as
636 -- build-in-place to include other composite result types.
638 if Ada_Version >= Ada_05
639 and then Is_Build_In_Place_Function_Call (Pref)
641 Make_Build_In_Place_Call_In_Anonymous_Context (Pref);
644 -- If prefix is a protected type name, this is a reference to
645 -- the current instance of the type.
647 if Is_Protected_Self_Reference (Pref) then
648 Rewrite (Pref, Concurrent_Ref (Pref));
652 -- Remaining processing depends on specific attribute
660 when Attribute_Access |
661 Attribute_Unchecked_Access |
662 Attribute_Unrestricted_Access =>
664 Access_Cases : declare
665 Ref_Object : constant Node_Id := Get_Referenced_Object (Pref);
666 Btyp_DDT : Entity_Id;
668 function Enclosing_Object (N : Node_Id) return Node_Id;
669 -- If N denotes a compound name (selected component, indexed
670 -- component, or slice), returns the name of the outermost
671 -- such enclosing object. Otherwise returns N. If the object
672 -- is a renaming, then the renamed object is returned.
674 ----------------------
675 -- Enclosing_Object --
676 ----------------------
678 function Enclosing_Object (N : Node_Id) return Node_Id is
683 while Nkind_In (Obj_Name, N_Selected_Component,
687 Obj_Name := Prefix (Obj_Name);
690 return Get_Referenced_Object (Obj_Name);
691 end Enclosing_Object;
693 -- Local declarations
695 Enc_Object : constant Node_Id := Enclosing_Object (Ref_Object);
697 -- Start of processing for Access_Cases
700 Btyp_DDT := Designated_Type (Btyp);
702 -- Handle designated types that come from the limited view
704 if Ekind (Btyp_DDT) = E_Incomplete_Type
705 and then From_With_Type (Btyp_DDT)
706 and then Present (Non_Limited_View (Btyp_DDT))
708 Btyp_DDT := Non_Limited_View (Btyp_DDT);
710 elsif Is_Class_Wide_Type (Btyp_DDT)
711 and then Ekind (Etype (Btyp_DDT)) = E_Incomplete_Type
712 and then From_With_Type (Etype (Btyp_DDT))
713 and then Present (Non_Limited_View (Etype (Btyp_DDT)))
714 and then Present (Class_Wide_Type
715 (Non_Limited_View (Etype (Btyp_DDT))))
718 Class_Wide_Type (Non_Limited_View (Etype (Btyp_DDT)));
721 -- In order to improve the text of error messages, the designated
722 -- type of access-to-subprogram itypes is set by the semantics as
723 -- the associated subprogram entity (see sem_attr). Now we replace
724 -- such node with the proper E_Subprogram_Type itype.
726 if Id = Attribute_Unrestricted_Access
727 and then Is_Subprogram (Directly_Designated_Type (Typ))
729 -- The following conditions ensure that this special management
730 -- is done only for "Address!(Prim'Unrestricted_Access)" nodes.
731 -- At this stage other cases in which the designated type is
732 -- still a subprogram (instead of an E_Subprogram_Type) are
733 -- wrong because the semantics must have overridden the type of
734 -- the node with the type imposed by the context.
736 if Nkind (Parent (N)) = N_Unchecked_Type_Conversion
737 and then Etype (Parent (N)) = RTE (RE_Prim_Ptr)
739 Set_Etype (N, RTE (RE_Prim_Ptr));
743 Subp : constant Entity_Id :=
744 Directly_Designated_Type (Typ);
746 Extra : Entity_Id := Empty;
747 New_Formal : Entity_Id;
748 Old_Formal : Entity_Id := First_Formal (Subp);
749 Subp_Typ : Entity_Id;
752 Subp_Typ := Create_Itype (E_Subprogram_Type, N);
753 Set_Etype (Subp_Typ, Etype (Subp));
754 Set_Returns_By_Ref (Subp_Typ, Returns_By_Ref (Subp));
756 if Present (Old_Formal) then
757 New_Formal := New_Copy (Old_Formal);
758 Set_First_Entity (Subp_Typ, New_Formal);
761 Set_Scope (New_Formal, Subp_Typ);
762 Etyp := Etype (New_Formal);
764 -- Handle itypes. There is no need to duplicate
765 -- here the itypes associated with record types
766 -- (i.e the implicit full view of private types).
769 and then Ekind (Base_Type (Etyp)) /= E_Record_Type
771 Extra := New_Copy (Etyp);
772 Set_Parent (Extra, New_Formal);
773 Set_Etype (New_Formal, Extra);
774 Set_Scope (Extra, Subp_Typ);
778 Next_Formal (Old_Formal);
779 exit when No (Old_Formal);
781 Set_Next_Entity (New_Formal,
782 New_Copy (Old_Formal));
783 Next_Entity (New_Formal);
786 Set_Next_Entity (New_Formal, Empty);
787 Set_Last_Entity (Subp_Typ, Extra);
790 -- Now that the explicit formals have been duplicated,
791 -- any extra formals needed by the subprogram must be
794 if Present (Extra) then
795 Set_Extra_Formal (Extra, Empty);
798 Create_Extra_Formals (Subp_Typ);
799 Set_Directly_Designated_Type (Typ, Subp_Typ);
804 if Is_Access_Protected_Subprogram_Type (Btyp) then
805 Expand_Access_To_Protected_Op (N, Pref, Typ);
807 -- If prefix is a type name, this is a reference to the current
808 -- instance of the type, within its initialization procedure.
810 elsif Is_Entity_Name (Pref)
811 and then Is_Type (Entity (Pref))
818 -- If the current instance name denotes a task type, then
819 -- the access attribute is rewritten to be the name of the
820 -- "_task" parameter associated with the task type's task
821 -- procedure. An unchecked conversion is applied to ensure
822 -- a type match in cases of expander-generated calls (e.g.
825 if Is_Task_Type (Entity (Pref)) then
827 First_Entity (Get_Task_Body_Procedure (Entity (Pref)));
828 while Present (Formal) loop
829 exit when Chars (Formal) = Name_uTask;
830 Next_Entity (Formal);
833 pragma Assert (Present (Formal));
836 Unchecked_Convert_To (Typ,
837 New_Occurrence_Of (Formal, Loc)));
840 -- The expression must appear in a default expression,
841 -- (which in the initialization procedure is the
842 -- right-hand side of an assignment), and not in a
843 -- discriminant constraint.
847 while Present (Par) loop
848 exit when Nkind (Par) = N_Assignment_Statement;
850 if Nkind (Par) = N_Component_Declaration then
857 if Present (Par) then
859 Make_Attribute_Reference (Loc,
860 Prefix => Make_Identifier (Loc, Name_uInit),
861 Attribute_Name => Attribute_Name (N)));
863 Analyze_And_Resolve (N, Typ);
868 -- If the prefix of an Access attribute is a dereference of an
869 -- access parameter (or a renaming of such a dereference, or a
870 -- subcomponent of such a dereference) and the context is a
871 -- general access type (including the type of an object or
872 -- component with an access_definition, but not the anonymous
873 -- type of an access parameter or access discriminant), then
874 -- apply an accessibility check to the access parameter. We used
875 -- to rewrite the access parameter as a type conversion, but that
876 -- could only be done if the immediate prefix of the Access
877 -- attribute was the dereference, and didn't handle cases where
878 -- the attribute is applied to a subcomponent of the dereference,
879 -- since there's generally no available, appropriate access type
880 -- to convert to in that case. The attribute is passed as the
881 -- point to insert the check, because the access parameter may
882 -- come from a renaming, possibly in a different scope, and the
883 -- check must be associated with the attribute itself.
885 elsif Id = Attribute_Access
886 and then Nkind (Enc_Object) = N_Explicit_Dereference
887 and then Is_Entity_Name (Prefix (Enc_Object))
888 and then (Ekind (Btyp) = E_General_Access_Type
889 or else Is_Local_Anonymous_Access (Btyp))
890 and then Ekind (Entity (Prefix (Enc_Object))) in Formal_Kind
891 and then Ekind (Etype (Entity (Prefix (Enc_Object))))
892 = E_Anonymous_Access_Type
893 and then Present (Extra_Accessibility
894 (Entity (Prefix (Enc_Object))))
896 Apply_Accessibility_Check (Prefix (Enc_Object), Typ, N);
898 -- Ada 2005 (AI-251): If the designated type is an interface we
899 -- add an implicit conversion to force the displacement of the
900 -- pointer to reference the secondary dispatch table.
902 elsif Is_Interface (Btyp_DDT)
903 and then (Comes_From_Source (N)
904 or else Comes_From_Source (Ref_Object)
905 or else (Nkind (Ref_Object) in N_Has_Chars
906 and then Chars (Ref_Object) = Name_uInit))
908 if Nkind (Ref_Object) /= N_Explicit_Dereference then
910 -- No implicit conversion required if types match
912 if Btyp_DDT /= Etype (Ref_Object) then
914 Convert_To (Btyp_DDT,
915 New_Copy_Tree (Prefix (N))));
917 Analyze_And_Resolve (Prefix (N), Btyp_DDT);
920 -- When the object is an explicit dereference, convert the
921 -- dereference's prefix.
925 Obj_DDT : constant Entity_Id :=
927 (Directly_Designated_Type
928 (Etype (Prefix (Ref_Object))));
930 -- No implicit conversion required if designated types
933 if Obj_DDT /= Btyp_DDT
934 and then not (Is_Class_Wide_Type (Obj_DDT)
935 and then Etype (Obj_DDT) = Btyp_DDT)
939 New_Copy_Tree (Prefix (Ref_Object))));
940 Analyze_And_Resolve (N, Typ);
951 -- Transforms 'Adjacent into a call to the floating-point attribute
952 -- function Adjacent in Fat_xxx (where xxx is the root type)
954 when Attribute_Adjacent =>
955 Expand_Fpt_Attribute_RR (N);
961 when Attribute_Address => Address : declare
962 Task_Proc : Entity_Id;
965 -- If the prefix is a task or a task type, the useful address is that
966 -- of the procedure for the task body, i.e. the actual program unit.
967 -- We replace the original entity with that of the procedure.
969 if Is_Entity_Name (Pref)
970 and then Is_Task_Type (Entity (Pref))
972 Task_Proc := Next_Entity (Root_Type (Ptyp));
974 while Present (Task_Proc) loop
975 exit when Ekind (Task_Proc) = E_Procedure
976 and then Etype (First_Formal (Task_Proc)) =
977 Corresponding_Record_Type (Ptyp);
978 Next_Entity (Task_Proc);
981 if Present (Task_Proc) then
982 Set_Entity (Pref, Task_Proc);
983 Set_Etype (Pref, Etype (Task_Proc));
986 -- Similarly, the address of a protected operation is the address
987 -- of the corresponding protected body, regardless of the protected
988 -- object from which it is selected.
990 elsif Nkind (Pref) = N_Selected_Component
991 and then Is_Subprogram (Entity (Selector_Name (Pref)))
992 and then Is_Protected_Type (Scope (Entity (Selector_Name (Pref))))
996 External_Subprogram (Entity (Selector_Name (Pref))), Loc));
998 elsif Nkind (Pref) = N_Explicit_Dereference
999 and then Ekind (Ptyp) = E_Subprogram_Type
1000 and then Convention (Ptyp) = Convention_Protected
1002 -- The prefix is be a dereference of an access_to_protected_
1003 -- subprogram. The desired address is the second component of
1004 -- the record that represents the access.
1007 Addr : constant Entity_Id := Etype (N);
1008 Ptr : constant Node_Id := Prefix (Pref);
1009 T : constant Entity_Id :=
1010 Equivalent_Type (Base_Type (Etype (Ptr)));
1014 Unchecked_Convert_To (Addr,
1015 Make_Selected_Component (Loc,
1016 Prefix => Unchecked_Convert_To (T, Ptr),
1017 Selector_Name => New_Occurrence_Of (
1018 Next_Entity (First_Entity (T)), Loc))));
1020 Analyze_And_Resolve (N, Addr);
1023 -- Ada 2005 (AI-251): Class-wide interface objects are always
1024 -- "displaced" to reference the tag associated with the interface
1025 -- type. In order to obtain the real address of such objects we
1026 -- generate a call to a run-time subprogram that returns the base
1027 -- address of the object.
1029 -- This processing is not needed in the VM case, where dispatching
1030 -- issues are taken care of by the virtual machine.
1032 elsif Is_Class_Wide_Type (Ptyp)
1033 and then Is_Interface (Ptyp)
1034 and then VM_Target = No_VM
1035 and then not (Nkind (Pref) in N_Has_Entity
1036 and then Is_Subprogram (Entity (Pref)))
1039 Make_Function_Call (Loc,
1040 Name => New_Reference_To (RTE (RE_Base_Address), Loc),
1041 Parameter_Associations => New_List (
1042 Relocate_Node (N))));
1047 -- Deal with packed array reference, other cases are handled by
1050 if Involves_Packed_Array_Reference (Pref) then
1051 Expand_Packed_Address_Reference (N);
1059 when Attribute_Alignment => Alignment : declare
1063 -- For class-wide types, X'Class'Alignment is transformed into a
1064 -- direct reference to the Alignment of the class type, so that the
1065 -- back end does not have to deal with the X'Class'Alignment
1068 if Is_Entity_Name (Pref)
1069 and then Is_Class_Wide_Type (Entity (Pref))
1071 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
1074 -- For x'Alignment applied to an object of a class wide type,
1075 -- transform X'Alignment into a call to the predefined primitive
1076 -- operation _Alignment applied to X.
1078 elsif Is_Class_Wide_Type (Ptyp) then
1080 -- No need to do anything else compiling under restriction
1081 -- No_Dispatching_Calls. During the semantic analysis we
1082 -- already notified such violation.
1084 if Restriction_Active (No_Dispatching_Calls) then
1089 Make_Function_Call (Loc,
1090 Name => New_Reference_To
1091 (Find_Prim_Op (Ptyp, Name_uAlignment), Loc),
1092 Parameter_Associations => New_List (Pref));
1094 if Typ /= Standard_Integer then
1096 -- The context is a specific integer type with which the
1097 -- original attribute was compatible. The function has a
1098 -- specific type as well, so to preserve the compatibility
1099 -- we must convert explicitly.
1101 New_Node := Convert_To (Typ, New_Node);
1104 Rewrite (N, New_Node);
1105 Analyze_And_Resolve (N, Typ);
1108 -- For all other cases, we just have to deal with the case of
1109 -- the fact that the result can be universal.
1112 Apply_Universal_Integer_Attribute_Checks (N);
1120 when Attribute_AST_Entry => AST_Entry : declare
1125 Entry_Ref : Node_Id;
1126 -- The reference to the entry or entry family
1129 -- The index expression for an entry family reference, or
1130 -- the Empty if Entry_Ref references a simple entry.
1133 if Nkind (Pref) = N_Indexed_Component then
1134 Entry_Ref := Prefix (Pref);
1135 Index := First (Expressions (Pref));
1141 -- Get expression for Task_Id and the entry entity
1143 if Nkind (Entry_Ref) = N_Selected_Component then
1145 Make_Attribute_Reference (Loc,
1146 Attribute_Name => Name_Identity,
1147 Prefix => Prefix (Entry_Ref));
1149 Ttyp := Etype (Prefix (Entry_Ref));
1150 Eent := Entity (Selector_Name (Entry_Ref));
1154 Make_Function_Call (Loc,
1155 Name => New_Occurrence_Of (RTE (RE_Current_Task), Loc));
1157 Eent := Entity (Entry_Ref);
1159 -- We have to find the enclosing task to get the task type
1160 -- There must be one, since we already validated this earlier
1162 Ttyp := Current_Scope;
1163 while not Is_Task_Type (Ttyp) loop
1164 Ttyp := Scope (Ttyp);
1168 -- Now rewrite the attribute with a call to Create_AST_Handler
1171 Make_Function_Call (Loc,
1172 Name => New_Occurrence_Of (RTE (RE_Create_AST_Handler), Loc),
1173 Parameter_Associations => New_List (
1175 Entry_Index_Expression (Loc, Eent, Index, Ttyp))));
1177 Analyze_And_Resolve (N, RTE (RE_AST_Handler));
1184 -- We compute this if a component clause was present, otherwise we leave
1185 -- the computation up to the back end, since we don't know what layout
1188 -- Note that the attribute can apply to a naked record component
1189 -- in generated code (i.e. the prefix is an identifier that
1190 -- references the component or discriminant entity).
1192 when Attribute_Bit_Position => Bit_Position :
1197 if Nkind (Pref) = N_Identifier then
1198 CE := Entity (Pref);
1200 CE := Entity (Selector_Name (Pref));
1203 if Known_Static_Component_Bit_Offset (CE) then
1205 Make_Integer_Literal (Loc,
1206 Intval => Component_Bit_Offset (CE)));
1207 Analyze_And_Resolve (N, Typ);
1210 Apply_Universal_Integer_Attribute_Checks (N);
1218 -- A reference to P'Body_Version or P'Version is expanded to
1221 -- pragma Import (C, Vnn, "uuuuT");
1223 -- Get_Version_String (Vnn)
1225 -- where uuuu is the unit name (dots replaced by double underscore)
1226 -- and T is B for the cases of Body_Version, or Version applied to a
1227 -- subprogram acting as its own spec, and S for Version applied to a
1228 -- subprogram spec or package. This sequence of code references the
1229 -- the unsigned constant created in the main program by the binder.
1231 -- A special exception occurs for Standard, where the string
1232 -- returned is a copy of the library string in gnatvsn.ads.
1234 when Attribute_Body_Version | Attribute_Version => Version : declare
1235 E : constant Entity_Id :=
1236 Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
1241 -- If not library unit, get to containing library unit
1243 Pent := Entity (Pref);
1244 while Pent /= Standard_Standard
1245 and then Scope (Pent) /= Standard_Standard
1246 and then not Is_Child_Unit (Pent)
1248 Pent := Scope (Pent);
1251 -- Special case Standard and Standard.ASCII
1253 if Pent = Standard_Standard or else Pent = Standard_ASCII then
1255 Make_String_Literal (Loc,
1256 Strval => Verbose_Library_Version));
1261 -- Build required string constant
1263 Get_Name_String (Get_Unit_Name (Pent));
1266 for J in 1 .. Name_Len - 2 loop
1267 if Name_Buffer (J) = '.' then
1268 Store_String_Chars ("__");
1270 Store_String_Char (Get_Char_Code (Name_Buffer (J)));
1274 -- Case of subprogram acting as its own spec, always use body
1276 if Nkind (Declaration_Node (Pent)) in N_Subprogram_Specification
1277 and then Nkind (Parent (Declaration_Node (Pent))) =
1279 and then Acts_As_Spec (Parent (Declaration_Node (Pent)))
1281 Store_String_Chars ("B");
1283 -- Case of no body present, always use spec
1285 elsif not Unit_Requires_Body (Pent) then
1286 Store_String_Chars ("S");
1288 -- Otherwise use B for Body_Version, S for spec
1290 elsif Id = Attribute_Body_Version then
1291 Store_String_Chars ("B");
1293 Store_String_Chars ("S");
1297 Lib.Version_Referenced (S);
1299 -- Insert the object declaration
1301 Insert_Actions (N, New_List (
1302 Make_Object_Declaration (Loc,
1303 Defining_Identifier => E,
1304 Object_Definition =>
1305 New_Occurrence_Of (RTE (RE_Unsigned), Loc))));
1307 -- Set entity as imported with correct external name
1309 Set_Is_Imported (E);
1310 Set_Interface_Name (E, Make_String_Literal (Loc, S));
1312 -- Set entity as internal to ensure proper Sprint output of its
1313 -- implicit importation.
1315 Set_Is_Internal (E);
1317 -- And now rewrite original reference
1320 Make_Function_Call (Loc,
1321 Name => New_Reference_To (RTE (RE_Get_Version_String), Loc),
1322 Parameter_Associations => New_List (
1323 New_Occurrence_Of (E, Loc))));
1326 Analyze_And_Resolve (N, RTE (RE_Version_String));
1333 -- Transforms 'Ceiling into a call to the floating-point attribute
1334 -- function Ceiling in Fat_xxx (where xxx is the root type)
1336 when Attribute_Ceiling =>
1337 Expand_Fpt_Attribute_R (N);
1343 -- Transforms 'Callable attribute into a call to the Callable function
1345 when Attribute_Callable => Callable :
1347 -- We have an object of a task interface class-wide type as a prefix
1348 -- to Callable. Generate:
1349 -- callable (Task_Id (Pref._disp_get_task_id));
1351 if Ada_Version >= Ada_05
1352 and then Ekind (Ptyp) = E_Class_Wide_Type
1353 and then Is_Interface (Ptyp)
1354 and then Is_Task_Interface (Ptyp)
1357 Make_Function_Call (Loc,
1359 New_Reference_To (RTE (RE_Callable), Loc),
1360 Parameter_Associations => New_List (
1361 Make_Unchecked_Type_Conversion (Loc,
1363 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
1365 Make_Selected_Component (Loc,
1367 New_Copy_Tree (Pref),
1369 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
1373 Build_Call_With_Task (Pref, RTE (RE_Callable)));
1376 Analyze_And_Resolve (N, Standard_Boolean);
1383 -- Transforms 'Caller attribute into a call to either the
1384 -- Task_Entry_Caller or the Protected_Entry_Caller function.
1386 when Attribute_Caller => Caller : declare
1387 Id_Kind : constant Entity_Id := RTE (RO_AT_Task_Id);
1388 Ent : constant Entity_Id := Entity (Pref);
1389 Conctype : constant Entity_Id := Scope (Ent);
1390 Nest_Depth : Integer := 0;
1397 if Is_Protected_Type (Conctype) then
1398 case Corresponding_Runtime_Package (Conctype) is
1399 when System_Tasking_Protected_Objects_Entries =>
1402 (RTE (RE_Protected_Entry_Caller), Loc);
1404 when System_Tasking_Protected_Objects_Single_Entry =>
1407 (RTE (RE_Protected_Single_Entry_Caller), Loc);
1410 raise Program_Error;
1414 Unchecked_Convert_To (Id_Kind,
1415 Make_Function_Call (Loc,
1417 Parameter_Associations => New_List (
1419 (Find_Protection_Object (Current_Scope), Loc)))));
1424 -- Determine the nesting depth of the E'Caller attribute, that
1425 -- is, how many accept statements are nested within the accept
1426 -- statement for E at the point of E'Caller. The runtime uses
1427 -- this depth to find the specified entry call.
1429 for J in reverse 0 .. Scope_Stack.Last loop
1430 S := Scope_Stack.Table (J).Entity;
1432 -- We should not reach the scope of the entry, as it should
1433 -- already have been checked in Sem_Attr that this attribute
1434 -- reference is within a matching accept statement.
1436 pragma Assert (S /= Conctype);
1441 elsif Is_Entry (S) then
1442 Nest_Depth := Nest_Depth + 1;
1447 Unchecked_Convert_To (Id_Kind,
1448 Make_Function_Call (Loc,
1450 New_Reference_To (RTE (RE_Task_Entry_Caller), Loc),
1451 Parameter_Associations => New_List (
1452 Make_Integer_Literal (Loc,
1453 Intval => Int (Nest_Depth))))));
1456 Analyze_And_Resolve (N, Id_Kind);
1463 -- Transforms 'Compose into a call to the floating-point attribute
1464 -- function Compose in Fat_xxx (where xxx is the root type)
1466 -- Note: we strictly should have special code here to deal with the
1467 -- case of absurdly negative arguments (less than Integer'First)
1468 -- which will return a (signed) zero value, but it hardly seems
1469 -- worth the effort. Absurdly large positive arguments will raise
1470 -- constraint error which is fine.
1472 when Attribute_Compose =>
1473 Expand_Fpt_Attribute_RI (N);
1479 when Attribute_Constrained => Constrained : declare
1480 Formal_Ent : constant Entity_Id := Param_Entity (Pref);
1482 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean;
1483 -- Ada 2005 (AI-363): Returns True if the object name Obj denotes a
1484 -- view of an aliased object whose subtype is constrained.
1486 ---------------------------------
1487 -- Is_Constrained_Aliased_View --
1488 ---------------------------------
1490 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean is
1494 if Is_Entity_Name (Obj) then
1497 if Present (Renamed_Object (E)) then
1498 return Is_Constrained_Aliased_View (Renamed_Object (E));
1500 return Is_Aliased (E) and then Is_Constrained (Etype (E));
1504 return Is_Aliased_View (Obj)
1506 (Is_Constrained (Etype (Obj))
1507 or else (Nkind (Obj) = N_Explicit_Dereference
1509 not Has_Constrained_Partial_View
1510 (Base_Type (Etype (Obj)))));
1512 end Is_Constrained_Aliased_View;
1514 -- Start of processing for Constrained
1517 -- Reference to a parameter where the value is passed as an extra
1518 -- actual, corresponding to the extra formal referenced by the
1519 -- Extra_Constrained field of the corresponding formal. If this
1520 -- is an entry in-parameter, it is replaced by a constant renaming
1521 -- for which Extra_Constrained is never created.
1523 if Present (Formal_Ent)
1524 and then Ekind (Formal_Ent) /= E_Constant
1525 and then Present (Extra_Constrained (Formal_Ent))
1529 (Extra_Constrained (Formal_Ent), Sloc (N)));
1531 -- For variables with a Extra_Constrained field, we use the
1532 -- corresponding entity.
1534 elsif Nkind (Pref) = N_Identifier
1535 and then Ekind (Entity (Pref)) = E_Variable
1536 and then Present (Extra_Constrained (Entity (Pref)))
1540 (Extra_Constrained (Entity (Pref)), Sloc (N)));
1542 -- For all other entity names, we can tell at compile time
1544 elsif Is_Entity_Name (Pref) then
1546 Ent : constant Entity_Id := Entity (Pref);
1550 -- (RM J.4) obsolescent cases
1552 if Is_Type (Ent) then
1556 if Is_Private_Type (Ent) then
1557 Res := not Has_Discriminants (Ent)
1558 or else Is_Constrained (Ent);
1560 -- It not a private type, must be a generic actual type
1561 -- that corresponded to a private type. We know that this
1562 -- correspondence holds, since otherwise the reference
1563 -- within the generic template would have been illegal.
1566 if Is_Composite_Type (Underlying_Type (Ent)) then
1567 Res := Is_Constrained (Ent);
1573 -- If the prefix is not a variable or is aliased, then
1574 -- definitely true; if it's a formal parameter without an
1575 -- associated extra formal, then treat it as constrained.
1577 -- Ada 2005 (AI-363): An aliased prefix must be known to be
1578 -- constrained in order to set the attribute to True.
1580 elsif not Is_Variable (Pref)
1581 or else Present (Formal_Ent)
1582 or else (Ada_Version < Ada_05
1583 and then Is_Aliased_View (Pref))
1584 or else (Ada_Version >= Ada_05
1585 and then Is_Constrained_Aliased_View (Pref))
1589 -- Variable case, look at type to see if it is constrained.
1590 -- Note that the one case where this is not accurate (the
1591 -- procedure formal case), has been handled above.
1593 -- We use the Underlying_Type here (and below) in case the
1594 -- type is private without discriminants, but the full type
1595 -- has discriminants. This case is illegal, but we generate it
1596 -- internally for passing to the Extra_Constrained parameter.
1599 Res := Is_Constrained (Underlying_Type (Etype (Ent)));
1603 New_Reference_To (Boolean_Literals (Res), Loc));
1606 -- Prefix is not an entity name. These are also cases where we can
1607 -- always tell at compile time by looking at the form and type of the
1608 -- prefix. If an explicit dereference of an object with constrained
1609 -- partial view, this is unconstrained (Ada 2005 AI-363).
1615 not Is_Variable (Pref)
1617 (Nkind (Pref) = N_Explicit_Dereference
1619 not Has_Constrained_Partial_View (Base_Type (Ptyp)))
1620 or else Is_Constrained (Underlying_Type (Ptyp))),
1624 Analyze_And_Resolve (N, Standard_Boolean);
1631 -- Transforms 'Copy_Sign into a call to the floating-point attribute
1632 -- function Copy_Sign in Fat_xxx (where xxx is the root type)
1634 when Attribute_Copy_Sign =>
1635 Expand_Fpt_Attribute_RR (N);
1641 -- Transforms 'Count attribute into a call to the Count function
1643 when Attribute_Count => Count : declare
1645 Conctyp : Entity_Id;
1647 Entry_Id : Entity_Id;
1652 -- If the prefix is a member of an entry family, retrieve both
1653 -- entry name and index. For a simple entry there is no index.
1655 if Nkind (Pref) = N_Indexed_Component then
1656 Entnam := Prefix (Pref);
1657 Index := First (Expressions (Pref));
1663 Entry_Id := Entity (Entnam);
1665 -- Find the concurrent type in which this attribute is referenced
1666 -- (there had better be one).
1668 Conctyp := Current_Scope;
1669 while not Is_Concurrent_Type (Conctyp) loop
1670 Conctyp := Scope (Conctyp);
1675 if Is_Protected_Type (Conctyp) then
1676 case Corresponding_Runtime_Package (Conctyp) is
1677 when System_Tasking_Protected_Objects_Entries =>
1678 Name := New_Reference_To (RTE (RE_Protected_Count), Loc);
1681 Make_Function_Call (Loc,
1683 Parameter_Associations => New_List (
1685 (Find_Protection_Object (Current_Scope), Loc),
1686 Entry_Index_Expression
1687 (Loc, Entry_Id, Index, Scope (Entry_Id))));
1689 when System_Tasking_Protected_Objects_Single_Entry =>
1691 New_Reference_To (RTE (RE_Protected_Count_Entry), Loc);
1694 Make_Function_Call (Loc,
1696 Parameter_Associations => New_List (
1698 (Find_Protection_Object (Current_Scope), Loc)));
1701 raise Program_Error;
1708 Make_Function_Call (Loc,
1709 Name => New_Reference_To (RTE (RE_Task_Count), Loc),
1710 Parameter_Associations => New_List (
1711 Entry_Index_Expression (Loc,
1712 Entry_Id, Index, Scope (Entry_Id))));
1715 -- The call returns type Natural but the context is universal integer
1716 -- so any integer type is allowed. The attribute was already resolved
1717 -- so its Etype is the required result type. If the base type of the
1718 -- context type is other than Standard.Integer we put in a conversion
1719 -- to the required type. This can be a normal typed conversion since
1720 -- both input and output types of the conversion are integer types
1722 if Base_Type (Typ) /= Base_Type (Standard_Integer) then
1723 Rewrite (N, Convert_To (Typ, Call));
1728 Analyze_And_Resolve (N, Typ);
1735 -- This processing is shared by Elab_Spec
1737 -- What we do is to insert the following declarations
1740 -- pragma Import (C, enn, "name___elabb/s");
1742 -- and then the Elab_Body/Spec attribute is replaced by a reference
1743 -- to this defining identifier.
1745 when Attribute_Elab_Body |
1746 Attribute_Elab_Spec =>
1749 Ent : constant Entity_Id :=
1750 Make_Defining_Identifier (Loc,
1751 New_Internal_Name ('E'));
1755 procedure Make_Elab_String (Nod : Node_Id);
1756 -- Given Nod, an identifier, or a selected component, put the
1757 -- image into the current string literal, with double underline
1758 -- between components.
1760 ----------------------
1761 -- Make_Elab_String --
1762 ----------------------
1764 procedure Make_Elab_String (Nod : Node_Id) is
1766 if Nkind (Nod) = N_Selected_Component then
1767 Make_Elab_String (Prefix (Nod));
1771 Store_String_Char ('$');
1773 Store_String_Char ('.');
1775 Store_String_Char ('_');
1776 Store_String_Char ('_');
1779 Get_Name_String (Chars (Selector_Name (Nod)));
1782 pragma Assert (Nkind (Nod) = N_Identifier);
1783 Get_Name_String (Chars (Nod));
1786 Store_String_Chars (Name_Buffer (1 .. Name_Len));
1787 end Make_Elab_String;
1789 -- Start of processing for Elab_Body/Elab_Spec
1792 -- First we need to prepare the string literal for the name of
1793 -- the elaboration routine to be referenced.
1796 Make_Elab_String (Pref);
1798 if VM_Target = No_VM then
1799 Store_String_Chars ("___elab");
1800 Lang := Make_Identifier (Loc, Name_C);
1802 Store_String_Chars ("._elab");
1803 Lang := Make_Identifier (Loc, Name_Ada);
1806 if Id = Attribute_Elab_Body then
1807 Store_String_Char ('b');
1809 Store_String_Char ('s');
1814 Insert_Actions (N, New_List (
1815 Make_Subprogram_Declaration (Loc,
1817 Make_Procedure_Specification (Loc,
1818 Defining_Unit_Name => Ent)),
1821 Chars => Name_Import,
1822 Pragma_Argument_Associations => New_List (
1823 Make_Pragma_Argument_Association (Loc,
1824 Expression => Lang),
1826 Make_Pragma_Argument_Association (Loc,
1828 Make_Identifier (Loc, Chars (Ent))),
1830 Make_Pragma_Argument_Association (Loc,
1832 Make_String_Literal (Loc, Str))))));
1834 Set_Entity (N, Ent);
1835 Rewrite (N, New_Occurrence_Of (Ent, Loc));
1842 -- Elaborated is always True for preelaborated units, predefined units,
1843 -- pure units and units which have Elaborate_Body pragmas. These units
1844 -- have no elaboration entity.
1846 -- Note: The Elaborated attribute is never passed to the back end
1848 when Attribute_Elaborated => Elaborated : declare
1849 Ent : constant Entity_Id := Entity (Pref);
1852 if Present (Elaboration_Entity (Ent)) then
1854 New_Occurrence_Of (Elaboration_Entity (Ent), Loc));
1856 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
1864 when Attribute_Enum_Rep => Enum_Rep :
1866 -- X'Enum_Rep (Y) expands to
1870 -- This is simply a direct conversion from the enumeration type to
1871 -- the target integer type, which is treated by the back end as a
1872 -- normal integer conversion, treating the enumeration type as an
1873 -- integer, which is exactly what we want! We set Conversion_OK to
1874 -- make sure that the analyzer does not complain about what otherwise
1875 -- might be an illegal conversion.
1877 if Is_Non_Empty_List (Exprs) then
1879 OK_Convert_To (Typ, Relocate_Node (First (Exprs))));
1881 -- X'Enum_Rep where X is an enumeration literal is replaced by
1882 -- the literal value.
1884 elsif Ekind (Entity (Pref)) = E_Enumeration_Literal then
1886 Make_Integer_Literal (Loc, Enumeration_Rep (Entity (Pref))));
1888 -- If this is a renaming of a literal, recover the representation
1891 elsif Ekind (Entity (Pref)) = E_Constant
1892 and then Present (Renamed_Object (Entity (Pref)))
1894 Ekind (Entity (Renamed_Object (Entity (Pref))))
1895 = E_Enumeration_Literal
1898 Make_Integer_Literal (Loc,
1899 Enumeration_Rep (Entity (Renamed_Object (Entity (Pref))))));
1901 -- X'Enum_Rep where X is an object does a direct unchecked conversion
1902 -- of the object value, as described for the type case above.
1906 OK_Convert_To (Typ, Relocate_Node (Pref)));
1910 Analyze_And_Resolve (N, Typ);
1917 when Attribute_Enum_Val => Enum_Val : declare
1919 Btyp : constant Entity_Id := Base_Type (Ptyp);
1922 -- X'Enum_Val (Y) expands to
1924 -- [constraint_error when _rep_to_pos (Y, False) = -1, msg]
1927 Expr := Unchecked_Convert_To (Ptyp, First (Exprs));
1930 Make_Raise_Constraint_Error (Loc,
1934 Make_Function_Call (Loc,
1936 New_Reference_To (TSS (Btyp, TSS_Rep_To_Pos), Loc),
1937 Parameter_Associations => New_List (
1938 Relocate_Node (Duplicate_Subexpr (Expr)),
1939 New_Occurrence_Of (Standard_False, Loc))),
1941 Right_Opnd => Make_Integer_Literal (Loc, -1)),
1942 Reason => CE_Range_Check_Failed));
1945 Analyze_And_Resolve (N, Ptyp);
1952 -- Transforms 'Exponent into a call to the floating-point attribute
1953 -- function Exponent in Fat_xxx (where xxx is the root type)
1955 when Attribute_Exponent =>
1956 Expand_Fpt_Attribute_R (N);
1962 -- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag)
1964 when Attribute_External_Tag => External_Tag :
1967 Make_Function_Call (Loc,
1968 Name => New_Reference_To (RTE (RE_External_Tag), Loc),
1969 Parameter_Associations => New_List (
1970 Make_Attribute_Reference (Loc,
1971 Attribute_Name => Name_Tag,
1972 Prefix => Prefix (N)))));
1974 Analyze_And_Resolve (N, Standard_String);
1981 when Attribute_First =>
1983 -- If the prefix type is a constrained packed array type which
1984 -- already has a Packed_Array_Type representation defined, then
1985 -- replace this attribute with a direct reference to 'First of the
1986 -- appropriate index subtype (since otherwise the back end will try
1987 -- to give us the value of 'First for this implementation type).
1989 if Is_Constrained_Packed_Array (Ptyp) then
1991 Make_Attribute_Reference (Loc,
1992 Attribute_Name => Name_First,
1993 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
1994 Analyze_And_Resolve (N, Typ);
1996 elsif Is_Access_Type (Ptyp) then
1997 Apply_Access_Check (N);
2004 -- Compute this if component clause was present, otherwise we leave the
2005 -- computation to be completed in the back-end, since we don't know what
2006 -- layout will be chosen.
2008 when Attribute_First_Bit => First_Bit : declare
2009 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2012 if Known_Static_Component_Bit_Offset (CE) then
2014 Make_Integer_Literal (Loc,
2015 Component_Bit_Offset (CE) mod System_Storage_Unit));
2017 Analyze_And_Resolve (N, Typ);
2020 Apply_Universal_Integer_Attribute_Checks (N);
2030 -- fixtype'Fixed_Value (integer-value)
2034 -- fixtype(integer-value)
2036 -- We do all the required analysis of the conversion here, because we do
2037 -- not want this to go through the fixed-point conversion circuits. Note
2038 -- that the back end always treats fixed-point as equivalent to the
2039 -- corresponding integer type anyway.
2041 when Attribute_Fixed_Value => Fixed_Value :
2044 Make_Type_Conversion (Loc,
2045 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2046 Expression => Relocate_Node (First (Exprs))));
2047 Set_Etype (N, Entity (Pref));
2050 -- Note: it might appear that a properly analyzed unchecked conversion
2051 -- would be just fine here, but that's not the case, since the full
2052 -- range checks performed by the following call are critical!
2054 Apply_Type_Conversion_Checks (N);
2061 -- Transforms 'Floor into a call to the floating-point attribute
2062 -- function Floor in Fat_xxx (where xxx is the root type)
2064 when Attribute_Floor =>
2065 Expand_Fpt_Attribute_R (N);
2071 -- For the fixed-point type Typ:
2077 -- Result_Type (System.Fore (Universal_Real (Type'First)),
2078 -- Universal_Real (Type'Last))
2080 -- Note that we know that the type is a non-static subtype, or Fore
2081 -- would have itself been computed dynamically in Eval_Attribute.
2083 when Attribute_Fore => Fore : begin
2086 Make_Function_Call (Loc,
2087 Name => New_Reference_To (RTE (RE_Fore), Loc),
2089 Parameter_Associations => New_List (
2090 Convert_To (Universal_Real,
2091 Make_Attribute_Reference (Loc,
2092 Prefix => New_Reference_To (Ptyp, Loc),
2093 Attribute_Name => Name_First)),
2095 Convert_To (Universal_Real,
2096 Make_Attribute_Reference (Loc,
2097 Prefix => New_Reference_To (Ptyp, Loc),
2098 Attribute_Name => Name_Last))))));
2100 Analyze_And_Resolve (N, Typ);
2107 -- Transforms 'Fraction into a call to the floating-point attribute
2108 -- function Fraction in Fat_xxx (where xxx is the root type)
2110 when Attribute_Fraction =>
2111 Expand_Fpt_Attribute_R (N);
2117 when Attribute_From_Any => From_Any : declare
2118 P_Type : constant Entity_Id := Etype (Pref);
2119 Decls : constant List_Id := New_List;
2122 Build_From_Any_Call (P_Type,
2123 Relocate_Node (First (Exprs)),
2125 Insert_Actions (N, Decls);
2126 Analyze_And_Resolve (N, P_Type);
2133 -- For an exception returns a reference to the exception data:
2134 -- Exception_Id!(Prefix'Reference)
2136 -- For a task it returns a reference to the _task_id component of
2137 -- corresponding record:
2139 -- taskV!(Prefix)._Task_Id, converted to the type Task_Id defined
2141 -- in Ada.Task_Identification
2143 when Attribute_Identity => Identity : declare
2144 Id_Kind : Entity_Id;
2147 if Ptyp = Standard_Exception_Type then
2148 Id_Kind := RTE (RE_Exception_Id);
2150 if Present (Renamed_Object (Entity (Pref))) then
2151 Set_Entity (Pref, Renamed_Object (Entity (Pref)));
2155 Unchecked_Convert_To (Id_Kind, Make_Reference (Loc, Pref)));
2157 Id_Kind := RTE (RO_AT_Task_Id);
2159 -- If the prefix is a task interface, the Task_Id is obtained
2160 -- dynamically through a dispatching call, as for other task
2161 -- attributes applied to interfaces.
2163 if Ada_Version >= Ada_05
2164 and then Ekind (Ptyp) = E_Class_Wide_Type
2165 and then Is_Interface (Ptyp)
2166 and then Is_Task_Interface (Ptyp)
2169 Unchecked_Convert_To (Id_Kind,
2170 Make_Selected_Component (Loc,
2172 New_Copy_Tree (Pref),
2174 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))));
2178 Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref)));
2182 Analyze_And_Resolve (N, Id_Kind);
2189 -- Image attribute is handled in separate unit Exp_Imgv
2191 when Attribute_Image =>
2192 Exp_Imgv.Expand_Image_Attribute (N);
2198 -- X'Img is expanded to typ'Image (X), where typ is the type of X
2200 when Attribute_Img => Img :
2203 Make_Attribute_Reference (Loc,
2204 Prefix => New_Reference_To (Ptyp, Loc),
2205 Attribute_Name => Name_Image,
2206 Expressions => New_List (Relocate_Node (Pref))));
2208 Analyze_And_Resolve (N, Standard_String);
2215 when Attribute_Input => Input : declare
2216 P_Type : constant Entity_Id := Entity (Pref);
2217 B_Type : constant Entity_Id := Base_Type (P_Type);
2218 U_Type : constant Entity_Id := Underlying_Type (P_Type);
2219 Strm : constant Node_Id := First (Exprs);
2227 Cntrl : Node_Id := Empty;
2228 -- Value for controlling argument in call. Always Empty except in
2229 -- the dispatching (class-wide type) case, where it is a reference
2230 -- to the dummy object initialized to the right internal tag.
2232 procedure Freeze_Stream_Subprogram (F : Entity_Id);
2233 -- The expansion of the attribute reference may generate a call to
2234 -- a user-defined stream subprogram that is frozen by the call. This
2235 -- can lead to access-before-elaboration problem if the reference
2236 -- appears in an object declaration and the subprogram body has not
2237 -- been seen. The freezing of the subprogram requires special code
2238 -- because it appears in an expanded context where expressions do
2239 -- not freeze their constituents.
2241 ------------------------------
2242 -- Freeze_Stream_Subprogram --
2243 ------------------------------
2245 procedure Freeze_Stream_Subprogram (F : Entity_Id) is
2246 Decl : constant Node_Id := Unit_Declaration_Node (F);
2250 -- If this is user-defined subprogram, the corresponding
2251 -- stream function appears as a renaming-as-body, and the
2252 -- user subprogram must be retrieved by tree traversal.
2255 and then Nkind (Decl) = N_Subprogram_Declaration
2256 and then Present (Corresponding_Body (Decl))
2258 Bod := Corresponding_Body (Decl);
2260 if Nkind (Unit_Declaration_Node (Bod)) =
2261 N_Subprogram_Renaming_Declaration
2263 Set_Is_Frozen (Entity (Name (Unit_Declaration_Node (Bod))));
2266 end Freeze_Stream_Subprogram;
2268 -- Start of processing for Input
2271 -- If no underlying type, we have an error that will be diagnosed
2272 -- elsewhere, so here we just completely ignore the expansion.
2278 -- If there is a TSS for Input, just call it
2280 Fname := Find_Stream_Subprogram (P_Type, TSS_Stream_Input);
2282 if Present (Fname) then
2286 -- If there is a Stream_Convert pragma, use it, we rewrite
2288 -- sourcetyp'Input (stream)
2292 -- sourcetyp (streamread (strmtyp'Input (stream)));
2294 -- where streamread is the given Read function that converts an
2295 -- argument of type strmtyp to type sourcetyp or a type from which
2296 -- it is derived (extra conversion required for the derived case).
2298 Prag := Get_Stream_Convert_Pragma (P_Type);
2300 if Present (Prag) then
2301 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
2302 Rfunc := Entity (Expression (Arg2));
2306 Make_Function_Call (Loc,
2307 Name => New_Occurrence_Of (Rfunc, Loc),
2308 Parameter_Associations => New_List (
2309 Make_Attribute_Reference (Loc,
2312 (Etype (First_Formal (Rfunc)), Loc),
2313 Attribute_Name => Name_Input,
2314 Expressions => Exprs)))));
2316 Analyze_And_Resolve (N, B_Type);
2321 elsif Is_Elementary_Type (U_Type) then
2323 -- A special case arises if we have a defined _Read routine,
2324 -- since in this case we are required to call this routine.
2326 if Present (TSS (Base_Type (U_Type), TSS_Stream_Read)) then
2327 Build_Record_Or_Elementary_Input_Function
2328 (Loc, U_Type, Decl, Fname);
2329 Insert_Action (N, Decl);
2331 -- For normal cases, we call the I_xxx routine directly
2334 Rewrite (N, Build_Elementary_Input_Call (N));
2335 Analyze_And_Resolve (N, P_Type);
2341 elsif Is_Array_Type (U_Type) then
2342 Build_Array_Input_Function (Loc, U_Type, Decl, Fname);
2343 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
2345 -- Dispatching case with class-wide type
2347 elsif Is_Class_Wide_Type (P_Type) then
2349 -- No need to do anything else compiling under restriction
2350 -- No_Dispatching_Calls. During the semantic analysis we
2351 -- already notified such violation.
2353 if Restriction_Active (No_Dispatching_Calls) then
2358 Rtyp : constant Entity_Id := Root_Type (P_Type);
2363 -- Read the internal tag (RM 13.13.2(34)) and use it to
2364 -- initialize a dummy tag object:
2366 -- Dnn : Ada.Tags.Tag
2367 -- := Descendant_Tag (String'Input (Strm), P_Type);
2369 -- This dummy object is used only to provide a controlling
2370 -- argument for the eventual _Input call. Descendant_Tag is
2371 -- called rather than Internal_Tag to ensure that we have a
2372 -- tag for a type that is descended from the prefix type and
2373 -- declared at the same accessibility level (the exception
2374 -- Tag_Error will be raised otherwise). The level check is
2375 -- required for Ada 2005 because tagged types can be
2376 -- extended in nested scopes (AI-344).
2379 Make_Defining_Identifier (Loc,
2380 Chars => New_Internal_Name ('D'));
2383 Make_Object_Declaration (Loc,
2384 Defining_Identifier => Dnn,
2385 Object_Definition =>
2386 New_Occurrence_Of (RTE (RE_Tag), Loc),
2388 Make_Function_Call (Loc,
2390 New_Occurrence_Of (RTE (RE_Descendant_Tag), Loc),
2391 Parameter_Associations => New_List (
2392 Make_Attribute_Reference (Loc,
2394 New_Occurrence_Of (Standard_String, Loc),
2395 Attribute_Name => Name_Input,
2396 Expressions => New_List (
2398 (Duplicate_Subexpr (Strm)))),
2399 Make_Attribute_Reference (Loc,
2400 Prefix => New_Reference_To (P_Type, Loc),
2401 Attribute_Name => Name_Tag))));
2403 Insert_Action (N, Decl);
2405 -- Now we need to get the entity for the call, and construct
2406 -- a function call node, where we preset a reference to Dnn
2407 -- as the controlling argument (doing an unchecked convert
2408 -- to the class-wide tagged type to make it look like a real
2411 Fname := Find_Prim_Op (Rtyp, TSS_Stream_Input);
2412 Cntrl := Unchecked_Convert_To (P_Type,
2413 New_Occurrence_Of (Dnn, Loc));
2414 Set_Etype (Cntrl, P_Type);
2415 Set_Parent (Cntrl, N);
2418 -- For tagged types, use the primitive Input function
2420 elsif Is_Tagged_Type (U_Type) then
2421 Fname := Find_Prim_Op (U_Type, TSS_Stream_Input);
2423 -- All other record type cases, including protected records. The
2424 -- latter only arise for expander generated code for handling
2425 -- shared passive partition access.
2429 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
2431 -- Ada 2005 (AI-216): Program_Error is raised executing default
2432 -- implementation of the Input attribute of an unchecked union
2433 -- type if the type lacks default discriminant values.
2435 if Is_Unchecked_Union (Base_Type (U_Type))
2436 and then No (Discriminant_Constraint (U_Type))
2439 Make_Raise_Program_Error (Loc,
2440 Reason => PE_Unchecked_Union_Restriction));
2445 Build_Record_Or_Elementary_Input_Function
2446 (Loc, Base_Type (U_Type), Decl, Fname);
2447 Insert_Action (N, Decl);
2449 if Nkind (Parent (N)) = N_Object_Declaration
2450 and then Is_Record_Type (U_Type)
2452 -- The stream function may contain calls to user-defined
2453 -- Read procedures for individual components.
2460 Comp := First_Component (U_Type);
2461 while Present (Comp) loop
2463 Find_Stream_Subprogram
2464 (Etype (Comp), TSS_Stream_Read);
2466 if Present (Func) then
2467 Freeze_Stream_Subprogram (Func);
2470 Next_Component (Comp);
2477 -- If we fall through, Fname is the function to be called. The result
2478 -- is obtained by calling the appropriate function, then converting
2479 -- the result. The conversion does a subtype check.
2482 Make_Function_Call (Loc,
2483 Name => New_Occurrence_Of (Fname, Loc),
2484 Parameter_Associations => New_List (
2485 Relocate_Node (Strm)));
2487 Set_Controlling_Argument (Call, Cntrl);
2488 Rewrite (N, Unchecked_Convert_To (P_Type, Call));
2489 Analyze_And_Resolve (N, P_Type);
2491 if Nkind (Parent (N)) = N_Object_Declaration then
2492 Freeze_Stream_Subprogram (Fname);
2502 -- inttype'Fixed_Value (fixed-value)
2506 -- inttype(integer-value))
2508 -- we do all the required analysis of the conversion here, because we do
2509 -- not want this to go through the fixed-point conversion circuits. Note
2510 -- that the back end always treats fixed-point as equivalent to the
2511 -- corresponding integer type anyway.
2513 when Attribute_Integer_Value => Integer_Value :
2516 Make_Type_Conversion (Loc,
2517 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2518 Expression => Relocate_Node (First (Exprs))));
2519 Set_Etype (N, Entity (Pref));
2522 -- Note: it might appear that a properly analyzed unchecked conversion
2523 -- would be just fine here, but that's not the case, since the full
2524 -- range checks performed by the following call are critical!
2526 Apply_Type_Conversion_Checks (N);
2533 when Attribute_Invalid_Value =>
2534 Rewrite (N, Get_Simple_Init_Val (Ptyp, N));
2540 when Attribute_Last =>
2542 -- If the prefix type is a constrained packed array type which
2543 -- already has a Packed_Array_Type representation defined, then
2544 -- replace this attribute with a direct reference to 'Last of the
2545 -- appropriate index subtype (since otherwise the back end will try
2546 -- to give us the value of 'Last for this implementation type).
2548 if Is_Constrained_Packed_Array (Ptyp) then
2550 Make_Attribute_Reference (Loc,
2551 Attribute_Name => Name_Last,
2552 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
2553 Analyze_And_Resolve (N, Typ);
2555 elsif Is_Access_Type (Ptyp) then
2556 Apply_Access_Check (N);
2563 -- We compute this if a component clause was present, otherwise we leave
2564 -- the computation up to the back end, since we don't know what layout
2567 when Attribute_Last_Bit => Last_Bit : declare
2568 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2571 if Known_Static_Component_Bit_Offset (CE)
2572 and then Known_Static_Esize (CE)
2575 Make_Integer_Literal (Loc,
2576 Intval => (Component_Bit_Offset (CE) mod System_Storage_Unit)
2579 Analyze_And_Resolve (N, Typ);
2582 Apply_Universal_Integer_Attribute_Checks (N);
2590 -- Transforms 'Leading_Part into a call to the floating-point attribute
2591 -- function Leading_Part in Fat_xxx (where xxx is the root type)
2593 -- Note: strictly, we should generate special case code to deal with
2594 -- absurdly large positive arguments (greater than Integer'Last), which
2595 -- result in returning the first argument unchanged, but it hardly seems
2596 -- worth the effort. We raise constraint error for absurdly negative
2597 -- arguments which is fine.
2599 when Attribute_Leading_Part =>
2600 Expand_Fpt_Attribute_RI (N);
2606 when Attribute_Length => declare
2611 -- Processing for packed array types
2613 if Is_Array_Type (Ptyp) and then Is_Packed (Ptyp) then
2614 Ityp := Get_Index_Subtype (N);
2616 -- If the index type, Ityp, is an enumeration type with holes,
2617 -- then we calculate X'Length explicitly using
2620 -- (0, Ityp'Pos (X'Last (N)) -
2621 -- Ityp'Pos (X'First (N)) + 1);
2623 -- Since the bounds in the template are the representation values
2624 -- and the back end would get the wrong value.
2626 if Is_Enumeration_Type (Ityp)
2627 and then Present (Enum_Pos_To_Rep (Base_Type (Ityp)))
2632 Xnum := Expr_Value (First (Expressions (N)));
2636 Make_Attribute_Reference (Loc,
2637 Prefix => New_Occurrence_Of (Typ, Loc),
2638 Attribute_Name => Name_Max,
2639 Expressions => New_List
2640 (Make_Integer_Literal (Loc, 0),
2644 Make_Op_Subtract (Loc,
2646 Make_Attribute_Reference (Loc,
2647 Prefix => New_Occurrence_Of (Ityp, Loc),
2648 Attribute_Name => Name_Pos,
2650 Expressions => New_List (
2651 Make_Attribute_Reference (Loc,
2652 Prefix => Duplicate_Subexpr (Pref),
2653 Attribute_Name => Name_Last,
2654 Expressions => New_List (
2655 Make_Integer_Literal (Loc, Xnum))))),
2658 Make_Attribute_Reference (Loc,
2659 Prefix => New_Occurrence_Of (Ityp, Loc),
2660 Attribute_Name => Name_Pos,
2662 Expressions => New_List (
2663 Make_Attribute_Reference (Loc,
2665 Duplicate_Subexpr_No_Checks (Pref),
2666 Attribute_Name => Name_First,
2667 Expressions => New_List (
2668 Make_Integer_Literal (Loc, Xnum)))))),
2670 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
2672 Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
2675 -- If the prefix type is a constrained packed array type which
2676 -- already has a Packed_Array_Type representation defined, then
2677 -- replace this attribute with a direct reference to 'Range_Length
2678 -- of the appropriate index subtype (since otherwise the back end
2679 -- will try to give us the value of 'Length for this
2680 -- implementation type).
2682 elsif Is_Constrained (Ptyp) then
2684 Make_Attribute_Reference (Loc,
2685 Attribute_Name => Name_Range_Length,
2686 Prefix => New_Reference_To (Ityp, Loc)));
2687 Analyze_And_Resolve (N, Typ);
2692 elsif Is_Access_Type (Ptyp) then
2693 Apply_Access_Check (N);
2695 -- If the designated type is a packed array type, then we convert
2696 -- the reference to:
2699 -- xtyp'Pos (Pref'Last (Expr)) -
2700 -- xtyp'Pos (Pref'First (Expr)));
2702 -- This is a bit complex, but it is the easiest thing to do that
2703 -- works in all cases including enum types with holes xtyp here
2704 -- is the appropriate index type.
2707 Dtyp : constant Entity_Id := Designated_Type (Ptyp);
2711 if Is_Array_Type (Dtyp) and then Is_Packed (Dtyp) then
2712 Xtyp := Get_Index_Subtype (N);
2715 Make_Attribute_Reference (Loc,
2716 Prefix => New_Occurrence_Of (Typ, Loc),
2717 Attribute_Name => Name_Max,
2718 Expressions => New_List (
2719 Make_Integer_Literal (Loc, 0),
2722 Make_Integer_Literal (Loc, 1),
2723 Make_Op_Subtract (Loc,
2725 Make_Attribute_Reference (Loc,
2726 Prefix => New_Occurrence_Of (Xtyp, Loc),
2727 Attribute_Name => Name_Pos,
2728 Expressions => New_List (
2729 Make_Attribute_Reference (Loc,
2730 Prefix => Duplicate_Subexpr (Pref),
2731 Attribute_Name => Name_Last,
2733 New_Copy_List (Exprs)))),
2736 Make_Attribute_Reference (Loc,
2737 Prefix => New_Occurrence_Of (Xtyp, Loc),
2738 Attribute_Name => Name_Pos,
2739 Expressions => New_List (
2740 Make_Attribute_Reference (Loc,
2742 Duplicate_Subexpr_No_Checks (Pref),
2743 Attribute_Name => Name_First,
2745 New_Copy_List (Exprs)))))))));
2747 Analyze_And_Resolve (N, Typ);
2751 -- Otherwise leave it to the back end
2754 Apply_Universal_Integer_Attribute_Checks (N);
2762 -- Transforms 'Machine into a call to the floating-point attribute
2763 -- function Machine in Fat_xxx (where xxx is the root type)
2765 when Attribute_Machine =>
2766 Expand_Fpt_Attribute_R (N);
2768 ----------------------
2769 -- Machine_Rounding --
2770 ----------------------
2772 -- Transforms 'Machine_Rounding into a call to the floating-point
2773 -- attribute function Machine_Rounding in Fat_xxx (where xxx is the root
2774 -- type). Expansion is avoided for cases the back end can handle
2777 when Attribute_Machine_Rounding =>
2778 if not Is_Inline_Floating_Point_Attribute (N) then
2779 Expand_Fpt_Attribute_R (N);
2786 -- Machine_Size is equivalent to Object_Size, so transform it into
2787 -- Object_Size and that way the back end never sees Machine_Size.
2789 when Attribute_Machine_Size =>
2791 Make_Attribute_Reference (Loc,
2792 Prefix => Prefix (N),
2793 Attribute_Name => Name_Object_Size));
2795 Analyze_And_Resolve (N, Typ);
2801 -- The only case that can get this far is the dynamic case of the old
2802 -- Ada 83 Mantissa attribute for the fixed-point case. For this case,
2809 -- ityp (System.Mantissa.Mantissa_Value
2810 -- (Integer'Integer_Value (typ'First),
2811 -- Integer'Integer_Value (typ'Last)));
2813 when Attribute_Mantissa => Mantissa : begin
2816 Make_Function_Call (Loc,
2817 Name => New_Occurrence_Of (RTE (RE_Mantissa_Value), Loc),
2819 Parameter_Associations => New_List (
2821 Make_Attribute_Reference (Loc,
2822 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2823 Attribute_Name => Name_Integer_Value,
2824 Expressions => New_List (
2826 Make_Attribute_Reference (Loc,
2827 Prefix => New_Occurrence_Of (Ptyp, Loc),
2828 Attribute_Name => Name_First))),
2830 Make_Attribute_Reference (Loc,
2831 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2832 Attribute_Name => Name_Integer_Value,
2833 Expressions => New_List (
2835 Make_Attribute_Reference (Loc,
2836 Prefix => New_Occurrence_Of (Ptyp, Loc),
2837 Attribute_Name => Name_Last)))))));
2839 Analyze_And_Resolve (N, Typ);
2842 --------------------
2843 -- Mechanism_Code --
2844 --------------------
2846 when Attribute_Mechanism_Code =>
2848 -- We must replace the prefix in the renamed case
2850 if Is_Entity_Name (Pref)
2851 and then Present (Alias (Entity (Pref)))
2853 Set_Renamed_Subprogram (Pref, Alias (Entity (Pref)));
2860 when Attribute_Mod => Mod_Case : declare
2861 Arg : constant Node_Id := Relocate_Node (First (Exprs));
2862 Hi : constant Node_Id := Type_High_Bound (Etype (Arg));
2863 Modv : constant Uint := Modulus (Btyp);
2867 -- This is not so simple. The issue is what type to use for the
2868 -- computation of the modular value.
2870 -- The easy case is when the modulus value is within the bounds
2871 -- of the signed integer type of the argument. In this case we can
2872 -- just do the computation in that signed integer type, and then
2873 -- do an ordinary conversion to the target type.
2875 if Modv <= Expr_Value (Hi) then
2880 Right_Opnd => Make_Integer_Literal (Loc, Modv))));
2882 -- Here we know that the modulus is larger than type'Last of the
2883 -- integer type. There are two cases to consider:
2885 -- a) The integer value is non-negative. In this case, it is
2886 -- returned as the result (since it is less than the modulus).
2888 -- b) The integer value is negative. In this case, we know that the
2889 -- result is modulus + value, where the value might be as small as
2890 -- -modulus. The trouble is what type do we use to do the subtract.
2891 -- No type will do, since modulus can be as big as 2**64, and no
2892 -- integer type accommodates this value. Let's do bit of algebra
2895 -- = modulus - (-value)
2896 -- = (modulus - 1) - (-value - 1)
2898 -- Now modulus - 1 is certainly in range of the modular type.
2899 -- -value is in the range 1 .. modulus, so -value -1 is in the
2900 -- range 0 .. modulus-1 which is in range of the modular type.
2901 -- Furthermore, (-value - 1) can be expressed as -(value + 1)
2902 -- which we can compute using the integer base type.
2904 -- Once this is done we analyze the conditional expression without
2905 -- range checks, because we know everything is in range, and we
2906 -- want to prevent spurious warnings on either branch.
2910 Make_Conditional_Expression (Loc,
2911 Expressions => New_List (
2913 Left_Opnd => Duplicate_Subexpr (Arg),
2914 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2917 Duplicate_Subexpr_No_Checks (Arg)),
2919 Make_Op_Subtract (Loc,
2921 Make_Integer_Literal (Loc,
2922 Intval => Modv - 1),
2928 Left_Opnd => Duplicate_Subexpr_No_Checks (Arg),
2930 Make_Integer_Literal (Loc,
2931 Intval => 1))))))));
2935 Analyze_And_Resolve (N, Btyp, Suppress => All_Checks);
2942 -- Transforms 'Model into a call to the floating-point attribute
2943 -- function Model in Fat_xxx (where xxx is the root type)
2945 when Attribute_Model =>
2946 Expand_Fpt_Attribute_R (N);
2952 -- The processing for Object_Size shares the processing for Size
2958 when Attribute_Old => Old : declare
2959 Tnn : constant Entity_Id :=
2960 Make_Defining_Identifier (Loc,
2961 Chars => New_Internal_Name ('T'));
2966 -- Find the nearest subprogram body, ignoring _Preconditions
2970 Subp := Parent (Subp);
2971 exit when Nkind (Subp) = N_Subprogram_Body
2972 and then Chars (Defining_Entity (Subp)) /= Name_uPostconditions;
2975 -- Insert the assignment at the start of the declarations
2978 Make_Object_Declaration (Loc,
2979 Defining_Identifier => Tnn,
2980 Constant_Present => True,
2981 Object_Definition => New_Occurrence_Of (Etype (N), Loc),
2982 Expression => Pref);
2984 if Is_Empty_List (Declarations (Subp)) then
2985 Set_Declarations (Subp, New_List (Asn_Stm));
2988 Insert_Action (First (Declarations (Subp)), Asn_Stm);
2991 Rewrite (N, New_Occurrence_Of (Tnn, Loc));
2998 when Attribute_Output => Output : declare
2999 P_Type : constant Entity_Id := Entity (Pref);
3000 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3008 -- If no underlying type, we have an error that will be diagnosed
3009 -- elsewhere, so here we just completely ignore the expansion.
3015 -- If TSS for Output is present, just call it
3017 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Output);
3019 if Present (Pname) then
3023 -- If there is a Stream_Convert pragma, use it, we rewrite
3025 -- sourcetyp'Output (stream, Item)
3029 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
3031 -- where strmwrite is the given Write function that converts an
3032 -- argument of type sourcetyp or a type acctyp, from which it is
3033 -- derived to type strmtyp. The conversion to acttyp is required
3034 -- for the derived case.
3036 Prag := Get_Stream_Convert_Pragma (P_Type);
3038 if Present (Prag) then
3040 Next (Next (First (Pragma_Argument_Associations (Prag))));
3041 Wfunc := Entity (Expression (Arg3));
3044 Make_Attribute_Reference (Loc,
3045 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
3046 Attribute_Name => Name_Output,
3047 Expressions => New_List (
3048 Relocate_Node (First (Exprs)),
3049 Make_Function_Call (Loc,
3050 Name => New_Occurrence_Of (Wfunc, Loc),
3051 Parameter_Associations => New_List (
3052 OK_Convert_To (Etype (First_Formal (Wfunc)),
3053 Relocate_Node (Next (First (Exprs)))))))));
3058 -- For elementary types, we call the W_xxx routine directly.
3059 -- Note that the effect of Write and Output is identical for
3060 -- the case of an elementary type, since there are no
3061 -- discriminants or bounds.
3063 elsif Is_Elementary_Type (U_Type) then
3065 -- A special case arises if we have a defined _Write routine,
3066 -- since in this case we are required to call this routine.
3068 if Present (TSS (Base_Type (U_Type), TSS_Stream_Write)) then
3069 Build_Record_Or_Elementary_Output_Procedure
3070 (Loc, U_Type, Decl, Pname);
3071 Insert_Action (N, Decl);
3073 -- For normal cases, we call the W_xxx routine directly
3076 Rewrite (N, Build_Elementary_Write_Call (N));
3083 elsif Is_Array_Type (U_Type) then
3084 Build_Array_Output_Procedure (Loc, U_Type, Decl, Pname);
3085 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3087 -- Class-wide case, first output external tag, then dispatch
3088 -- to the appropriate primitive Output function (RM 13.13.2(31)).
3090 elsif Is_Class_Wide_Type (P_Type) then
3092 -- No need to do anything else compiling under restriction
3093 -- No_Dispatching_Calls. During the semantic analysis we
3094 -- already notified such violation.
3096 if Restriction_Active (No_Dispatching_Calls) then
3101 Strm : constant Node_Id := First (Exprs);
3102 Item : constant Node_Id := Next (Strm);
3105 -- Ada 2005 (AI-344): Check that the accessibility level
3106 -- of the type of the output object is not deeper than
3107 -- that of the attribute's prefix type.
3109 -- if Get_Access_Level (Item'Tag)
3110 -- /= Get_Access_Level (P_Type'Tag)
3115 -- String'Output (Strm, External_Tag (Item'Tag));
3117 -- We cannot figure out a practical way to implement this
3118 -- accessibility check on virtual machines, so we omit it.
3120 if Ada_Version >= Ada_05
3121 and then VM_Target = No_VM
3124 Make_Implicit_If_Statement (N,
3128 Build_Get_Access_Level (Loc,
3129 Make_Attribute_Reference (Loc,
3132 Duplicate_Subexpr (Item,
3134 Attribute_Name => Name_Tag)),
3137 Make_Integer_Literal (Loc,
3138 Type_Access_Level (P_Type))),
3141 New_List (Make_Raise_Statement (Loc,
3143 RTE (RE_Tag_Error), Loc)))));
3147 Make_Attribute_Reference (Loc,
3148 Prefix => New_Occurrence_Of (Standard_String, Loc),
3149 Attribute_Name => Name_Output,
3150 Expressions => New_List (
3151 Relocate_Node (Duplicate_Subexpr (Strm)),
3152 Make_Function_Call (Loc,
3154 New_Occurrence_Of (RTE (RE_External_Tag), Loc),
3155 Parameter_Associations => New_List (
3156 Make_Attribute_Reference (Loc,
3159 (Duplicate_Subexpr (Item, Name_Req => True)),
3160 Attribute_Name => Name_Tag))))));
3163 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
3165 -- Tagged type case, use the primitive Output function
3167 elsif Is_Tagged_Type (U_Type) then
3168 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
3170 -- All other record type cases, including protected records.
3171 -- The latter only arise for expander generated code for
3172 -- handling shared passive partition access.
3176 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3178 -- Ada 2005 (AI-216): Program_Error is raised when executing
3179 -- the default implementation of the Output attribute of an
3180 -- unchecked union type if the type lacks default discriminant
3183 if Is_Unchecked_Union (Base_Type (U_Type))
3184 and then No (Discriminant_Constraint (U_Type))
3187 Make_Raise_Program_Error (Loc,
3188 Reason => PE_Unchecked_Union_Restriction));
3193 Build_Record_Or_Elementary_Output_Procedure
3194 (Loc, Base_Type (U_Type), Decl, Pname);
3195 Insert_Action (N, Decl);
3199 -- If we fall through, Pname is the name of the procedure to call
3201 Rewrite_Stream_Proc_Call (Pname);
3208 -- For enumeration types with a standard representation, Pos is
3209 -- handled by the back end.
3211 -- For enumeration types, with a non-standard representation we
3212 -- generate a call to the _Rep_To_Pos function created when the
3213 -- type was frozen. The call has the form
3215 -- _rep_to_pos (expr, flag)
3217 -- The parameter flag is True if range checks are enabled, causing
3218 -- Program_Error to be raised if the expression has an invalid
3219 -- representation, and False if range checks are suppressed.
3221 -- For integer types, Pos is equivalent to a simple integer
3222 -- conversion and we rewrite it as such
3224 when Attribute_Pos => Pos :
3226 Etyp : Entity_Id := Base_Type (Entity (Pref));
3229 -- Deal with zero/non-zero boolean values
3231 if Is_Boolean_Type (Etyp) then
3232 Adjust_Condition (First (Exprs));
3233 Etyp := Standard_Boolean;
3234 Set_Prefix (N, New_Occurrence_Of (Standard_Boolean, Loc));
3237 -- Case of enumeration type
3239 if Is_Enumeration_Type (Etyp) then
3241 -- Non-standard enumeration type (generate call)
3243 if Present (Enum_Pos_To_Rep (Etyp)) then
3244 Append_To (Exprs, Rep_To_Pos_Flag (Etyp, Loc));
3247 Make_Function_Call (Loc,
3249 New_Reference_To (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3250 Parameter_Associations => Exprs)));
3252 Analyze_And_Resolve (N, Typ);
3254 -- Standard enumeration type (do universal integer check)
3257 Apply_Universal_Integer_Attribute_Checks (N);
3260 -- Deal with integer types (replace by conversion)
3262 elsif Is_Integer_Type (Etyp) then
3263 Rewrite (N, Convert_To (Typ, First (Exprs)));
3264 Analyze_And_Resolve (N, Typ);
3273 -- We compute this if a component clause was present, otherwise we leave
3274 -- the computation up to the back end, since we don't know what layout
3277 when Attribute_Position => Position :
3279 CE : constant Entity_Id := Entity (Selector_Name (Pref));
3282 if Present (Component_Clause (CE)) then
3284 Make_Integer_Literal (Loc,
3285 Intval => Component_Bit_Offset (CE) / System_Storage_Unit));
3286 Analyze_And_Resolve (N, Typ);
3289 Apply_Universal_Integer_Attribute_Checks (N);
3297 -- 1. Deal with enumeration types with holes
3298 -- 2. For floating-point, generate call to attribute function
3299 -- 3. For other cases, deal with constraint checking
3301 when Attribute_Pred => Pred :
3303 Etyp : constant Entity_Id := Base_Type (Ptyp);
3307 -- For enumeration types with non-standard representations, we
3308 -- expand typ'Pred (x) into
3310 -- Pos_To_Rep (Rep_To_Pos (x) - 1)
3312 -- If the representation is contiguous, we compute instead
3313 -- Lit1 + Rep_to_Pos (x -1), to catch invalid representations.
3314 -- The conversion function Enum_Pos_To_Rep is defined on the
3315 -- base type, not the subtype, so we have to use the base type
3316 -- explicitly for this and other enumeration attributes.
3318 if Is_Enumeration_Type (Ptyp)
3319 and then Present (Enum_Pos_To_Rep (Etyp))
3321 if Has_Contiguous_Rep (Etyp) then
3323 Unchecked_Convert_To (Ptyp,
3326 Make_Integer_Literal (Loc,
3327 Enumeration_Rep (First_Literal (Ptyp))),
3329 Make_Function_Call (Loc,
3332 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3334 Parameter_Associations =>
3336 Unchecked_Convert_To (Ptyp,
3337 Make_Op_Subtract (Loc,
3339 Unchecked_Convert_To (Standard_Integer,
3340 Relocate_Node (First (Exprs))),
3342 Make_Integer_Literal (Loc, 1))),
3343 Rep_To_Pos_Flag (Ptyp, Loc))))));
3346 -- Add Boolean parameter True, to request program errror if
3347 -- we have a bad representation on our hands. If checks are
3348 -- suppressed, then add False instead
3350 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
3352 Make_Indexed_Component (Loc,
3355 (Enum_Pos_To_Rep (Etyp), Loc),
3356 Expressions => New_List (
3357 Make_Op_Subtract (Loc,
3359 Make_Function_Call (Loc,
3362 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3363 Parameter_Associations => Exprs),
3364 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
3367 Analyze_And_Resolve (N, Typ);
3369 -- For floating-point, we transform 'Pred into a call to the Pred
3370 -- floating-point attribute function in Fat_xxx (xxx is root type)
3372 elsif Is_Floating_Point_Type (Ptyp) then
3373 Expand_Fpt_Attribute_R (N);
3374 Analyze_And_Resolve (N, Typ);
3376 -- For modular types, nothing to do (no overflow, since wraps)
3378 elsif Is_Modular_Integer_Type (Ptyp) then
3381 -- For other types, if range checking is enabled, we must generate
3382 -- a check if overflow checking is enabled.
3384 elsif not Overflow_Checks_Suppressed (Ptyp) then
3385 Expand_Pred_Succ (N);
3393 -- Ada 2005 (AI-327): Dynamic ceiling priorities
3395 -- We rewrite X'Priority as the following run-time call:
3397 -- Get_Ceiling (X._Object)
3399 -- Note that although X'Priority is notionally an object, it is quite
3400 -- deliberately not defined as an aliased object in the RM. This means
3401 -- that it works fine to rewrite it as a call, without having to worry
3402 -- about complications that would other arise from X'Priority'Access,
3403 -- which is illegal, because of the lack of aliasing.
3405 when Attribute_Priority =>
3408 Conctyp : Entity_Id;
3409 Object_Parm : Node_Id;
3411 RT_Subprg_Name : Node_Id;
3414 -- Look for the enclosing concurrent type
3416 Conctyp := Current_Scope;
3417 while not Is_Concurrent_Type (Conctyp) loop
3418 Conctyp := Scope (Conctyp);
3421 pragma Assert (Is_Protected_Type (Conctyp));
3423 -- Generate the actual of the call
3425 Subprg := Current_Scope;
3426 while not Present (Protected_Body_Subprogram (Subprg)) loop
3427 Subprg := Scope (Subprg);
3430 -- Use of 'Priority inside protected entries and barriers (in
3431 -- both cases the type of the first formal of their expanded
3432 -- subprogram is Address)
3434 if Etype (First_Entity (Protected_Body_Subprogram (Subprg)))
3438 New_Itype : Entity_Id;
3441 -- In the expansion of protected entries the type of the
3442 -- first formal of the Protected_Body_Subprogram is an
3443 -- Address. In order to reference the _object component
3446 -- type T is access p__ptTV;
3449 New_Itype := Create_Itype (E_Access_Type, N);
3450 Set_Etype (New_Itype, New_Itype);
3451 Set_Directly_Designated_Type (New_Itype,
3452 Corresponding_Record_Type (Conctyp));
3453 Freeze_Itype (New_Itype, N);
3456 -- T!(O)._object'unchecked_access
3459 Make_Attribute_Reference (Loc,
3461 Make_Selected_Component (Loc,
3463 Unchecked_Convert_To (New_Itype,
3466 (Protected_Body_Subprogram (Subprg)),
3469 Make_Identifier (Loc, Name_uObject)),
3470 Attribute_Name => Name_Unchecked_Access);
3473 -- Use of 'Priority inside a protected subprogram
3477 Make_Attribute_Reference (Loc,
3479 Make_Selected_Component (Loc,
3480 Prefix => New_Reference_To
3482 (Protected_Body_Subprogram (Subprg)),
3485 Make_Identifier (Loc, Name_uObject)),
3486 Attribute_Name => Name_Unchecked_Access);
3489 -- Select the appropriate run-time subprogram
3491 if Number_Entries (Conctyp) = 0 then
3493 New_Reference_To (RTE (RE_Get_Ceiling), Loc);
3496 New_Reference_To (RTE (RO_PE_Get_Ceiling), Loc);
3500 Make_Function_Call (Loc,
3501 Name => RT_Subprg_Name,
3502 Parameter_Associations => New_List (Object_Parm));
3506 -- Avoid the generation of extra checks on the pointer to the
3507 -- protected object.
3509 Analyze_And_Resolve (N, Typ, Suppress => Access_Check);
3516 when Attribute_Range_Length => Range_Length : begin
3517 -- The only special processing required is for the case where
3518 -- Range_Length is applied to an enumeration type with holes.
3519 -- In this case we transform
3525 -- X'Pos (X'Last) - X'Pos (X'First) + 1
3527 -- So that the result reflects the proper Pos values instead
3528 -- of the underlying representations.
3530 if Is_Enumeration_Type (Ptyp)
3531 and then Has_Non_Standard_Rep (Ptyp)
3536 Make_Op_Subtract (Loc,
3538 Make_Attribute_Reference (Loc,
3539 Attribute_Name => Name_Pos,
3540 Prefix => New_Occurrence_Of (Ptyp, Loc),
3541 Expressions => New_List (
3542 Make_Attribute_Reference (Loc,
3543 Attribute_Name => Name_Last,
3544 Prefix => New_Occurrence_Of (Ptyp, Loc)))),
3547 Make_Attribute_Reference (Loc,
3548 Attribute_Name => Name_Pos,
3549 Prefix => New_Occurrence_Of (Ptyp, Loc),
3550 Expressions => New_List (
3551 Make_Attribute_Reference (Loc,
3552 Attribute_Name => Name_First,
3553 Prefix => New_Occurrence_Of (Ptyp, Loc))))),
3556 Make_Integer_Literal (Loc, 1)));
3558 Analyze_And_Resolve (N, Typ);
3560 -- For all other cases, the attribute is handled by the back end, but
3561 -- we need to deal with the case of the range check on a universal
3565 Apply_Universal_Integer_Attribute_Checks (N);
3573 when Attribute_Read => Read : declare
3574 P_Type : constant Entity_Id := Entity (Pref);
3575 B_Type : constant Entity_Id := Base_Type (P_Type);
3576 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3586 -- If no underlying type, we have an error that will be diagnosed
3587 -- elsewhere, so here we just completely ignore the expansion.
3593 -- The simple case, if there is a TSS for Read, just call it
3595 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Read);
3597 if Present (Pname) then
3601 -- If there is a Stream_Convert pragma, use it, we rewrite
3603 -- sourcetyp'Read (stream, Item)
3607 -- Item := sourcetyp (strmread (strmtyp'Input (Stream)));
3609 -- where strmread is the given Read function that converts an
3610 -- argument of type strmtyp to type sourcetyp or a type from which
3611 -- it is derived. The conversion to sourcetyp is required in the
3614 -- A special case arises if Item is a type conversion in which
3615 -- case, we have to expand to:
3617 -- Itemx := typex (strmread (strmtyp'Input (Stream)));
3619 -- where Itemx is the expression of the type conversion (i.e.
3620 -- the actual object), and typex is the type of Itemx.
3622 Prag := Get_Stream_Convert_Pragma (P_Type);
3624 if Present (Prag) then
3625 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
3626 Rfunc := Entity (Expression (Arg2));
3627 Lhs := Relocate_Node (Next (First (Exprs)));
3629 OK_Convert_To (B_Type,
3630 Make_Function_Call (Loc,
3631 Name => New_Occurrence_Of (Rfunc, Loc),
3632 Parameter_Associations => New_List (
3633 Make_Attribute_Reference (Loc,
3636 (Etype (First_Formal (Rfunc)), Loc),
3637 Attribute_Name => Name_Input,
3638 Expressions => New_List (
3639 Relocate_Node (First (Exprs)))))));
3641 if Nkind (Lhs) = N_Type_Conversion then
3642 Lhs := Expression (Lhs);
3643 Rhs := Convert_To (Etype (Lhs), Rhs);
3647 Make_Assignment_Statement (Loc,
3649 Expression => Rhs));
3650 Set_Assignment_OK (Lhs);
3654 -- For elementary types, we call the I_xxx routine using the first
3655 -- parameter and then assign the result into the second parameter.
3656 -- We set Assignment_OK to deal with the conversion case.
3658 elsif Is_Elementary_Type (U_Type) then
3664 Lhs := Relocate_Node (Next (First (Exprs)));
3665 Rhs := Build_Elementary_Input_Call (N);
3667 if Nkind (Lhs) = N_Type_Conversion then
3668 Lhs := Expression (Lhs);
3669 Rhs := Convert_To (Etype (Lhs), Rhs);
3672 Set_Assignment_OK (Lhs);
3675 Make_Assignment_Statement (Loc,
3677 Expression => Rhs));
3685 elsif Is_Array_Type (U_Type) then
3686 Build_Array_Read_Procedure (N, U_Type, Decl, Pname);
3687 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3689 -- Tagged type case, use the primitive Read function. Note that
3690 -- this will dispatch in the class-wide case which is what we want
3692 elsif Is_Tagged_Type (U_Type) then
3693 Pname := Find_Prim_Op (U_Type, TSS_Stream_Read);
3695 -- All other record type cases, including protected records. The
3696 -- latter only arise for expander generated code for handling
3697 -- shared passive partition access.
3701 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3703 -- Ada 2005 (AI-216): Program_Error is raised when executing
3704 -- the default implementation of the Read attribute of an
3705 -- Unchecked_Union type.
3707 if Is_Unchecked_Union (Base_Type (U_Type)) then
3709 Make_Raise_Program_Error (Loc,
3710 Reason => PE_Unchecked_Union_Restriction));
3713 if Has_Discriminants (U_Type)
3715 (Discriminant_Default_Value (First_Discriminant (U_Type)))
3717 Build_Mutable_Record_Read_Procedure
3718 (Loc, Base_Type (U_Type), Decl, Pname);
3720 Build_Record_Read_Procedure
3721 (Loc, Base_Type (U_Type), Decl, Pname);
3724 -- Suppress checks, uninitialized or otherwise invalid
3725 -- data does not cause constraint errors to be raised for
3726 -- a complete record read.
3728 Insert_Action (N, Decl, All_Checks);
3732 Rewrite_Stream_Proc_Call (Pname);
3739 -- Transforms 'Remainder into a call to the floating-point attribute
3740 -- function Remainder in Fat_xxx (where xxx is the root type)
3742 when Attribute_Remainder =>
3743 Expand_Fpt_Attribute_RR (N);
3749 -- Transform 'Result into reference to _Result formal. At the point
3750 -- where a legal 'Result attribute is expanded, we know that we are in
3751 -- the context of a _Postcondition function with a _Result parameter.
3753 when Attribute_Result =>
3755 Make_Identifier (Loc,
3756 Chars => Name_uResult));
3757 Analyze_And_Resolve (N, Typ);
3763 -- The handling of the Round attribute is quite delicate. The processing
3764 -- in Sem_Attr introduced a conversion to universal real, reflecting the
3765 -- semantics of Round, but we do not want anything to do with universal
3766 -- real at runtime, since this corresponds to using floating-point
3769 -- What we have now is that the Etype of the Round attribute correctly
3770 -- indicates the final result type. The operand of the Round is the
3771 -- conversion to universal real, described above, and the operand of
3772 -- this conversion is the actual operand of Round, which may be the
3773 -- special case of a fixed point multiplication or division (Etype =
3776 -- The exapander will expand first the operand of the conversion, then
3777 -- the conversion, and finally the round attribute itself, since we
3778 -- always work inside out. But we cannot simply process naively in this
3779 -- order. In the semantic world where universal fixed and real really
3780 -- exist and have infinite precision, there is no problem, but in the
3781 -- implementation world, where universal real is a floating-point type,
3782 -- we would get the wrong result.
3784 -- So the approach is as follows. First, when expanding a multiply or
3785 -- divide whose type is universal fixed, we do nothing at all, instead
3786 -- deferring the operation till later.
3788 -- The actual processing is done in Expand_N_Type_Conversion which
3789 -- handles the special case of Round by looking at its parent to see if
3790 -- it is a Round attribute, and if it is, handling the conversion (or
3791 -- its fixed multiply/divide child) in an appropriate manner.
3793 -- This means that by the time we get to expanding the Round attribute
3794 -- itself, the Round is nothing more than a type conversion (and will
3795 -- often be a null type conversion), so we just replace it with the
3796 -- appropriate conversion operation.
3798 when Attribute_Round =>
3800 Convert_To (Etype (N), Relocate_Node (First (Exprs))));
3801 Analyze_And_Resolve (N);
3807 -- Transforms 'Rounding into a call to the floating-point attribute
3808 -- function Rounding in Fat_xxx (where xxx is the root type)
3810 when Attribute_Rounding =>
3811 Expand_Fpt_Attribute_R (N);
3817 -- Transforms 'Scaling into a call to the floating-point attribute
3818 -- function Scaling in Fat_xxx (where xxx is the root type)
3820 when Attribute_Scaling =>
3821 Expand_Fpt_Attribute_RI (N);
3827 when Attribute_Size |
3828 Attribute_Object_Size |
3829 Attribute_Value_Size |
3830 Attribute_VADS_Size => Size :
3837 -- Processing for VADS_Size case. Note that this processing removes
3838 -- all traces of VADS_Size from the tree, and completes all required
3839 -- processing for VADS_Size by translating the attribute reference
3840 -- to an appropriate Size or Object_Size reference.
3842 if Id = Attribute_VADS_Size
3843 or else (Use_VADS_Size and then Id = Attribute_Size)
3845 -- If the size is specified, then we simply use the specified
3846 -- size. This applies to both types and objects. The size of an
3847 -- object can be specified in the following ways:
3849 -- An explicit size object is given for an object
3850 -- A component size is specified for an indexed component
3851 -- A component clause is specified for a selected component
3852 -- The object is a component of a packed composite object
3854 -- If the size is specified, then VADS_Size of an object
3856 if (Is_Entity_Name (Pref)
3857 and then Present (Size_Clause (Entity (Pref))))
3859 (Nkind (Pref) = N_Component_Clause
3860 and then (Present (Component_Clause
3861 (Entity (Selector_Name (Pref))))
3862 or else Is_Packed (Etype (Prefix (Pref)))))
3864 (Nkind (Pref) = N_Indexed_Component
3865 and then (Component_Size (Etype (Prefix (Pref))) /= 0
3866 or else Is_Packed (Etype (Prefix (Pref)))))
3868 Set_Attribute_Name (N, Name_Size);
3870 -- Otherwise if we have an object rather than a type, then the
3871 -- VADS_Size attribute applies to the type of the object, rather
3872 -- than the object itself. This is one of the respects in which
3873 -- VADS_Size differs from Size.
3876 if (not Is_Entity_Name (Pref)
3877 or else not Is_Type (Entity (Pref)))
3878 and then (Is_Scalar_Type (Ptyp) or else Is_Constrained (Ptyp))
3880 Rewrite (Pref, New_Occurrence_Of (Ptyp, Loc));
3883 -- For a scalar type for which no size was explicitly given,
3884 -- VADS_Size means Object_Size. This is the other respect in
3885 -- which VADS_Size differs from Size.
3887 if Is_Scalar_Type (Ptyp) and then No (Size_Clause (Ptyp)) then
3888 Set_Attribute_Name (N, Name_Object_Size);
3890 -- In all other cases, Size and VADS_Size are the sane
3893 Set_Attribute_Name (N, Name_Size);
3898 -- For class-wide types, X'Class'Size is transformed into a direct
3899 -- reference to the Size of the class type, so that the back end does
3900 -- not have to deal with the X'Class'Size reference.
3902 if Is_Entity_Name (Pref)
3903 and then Is_Class_Wide_Type (Entity (Pref))
3905 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
3908 -- For X'Size applied to an object of a class-wide type, transform
3909 -- X'Size into a call to the primitive operation _Size applied to X.
3911 elsif Is_Class_Wide_Type (Ptyp)
3912 or else (Id = Attribute_Size
3913 and then Is_Tagged_Type (Ptyp)
3914 and then Has_Unknown_Discriminants (Ptyp))
3916 -- No need to do anything else compiling under restriction
3917 -- No_Dispatching_Calls. During the semantic analysis we
3918 -- already notified such violation.
3920 if Restriction_Active (No_Dispatching_Calls) then
3925 Make_Function_Call (Loc,
3926 Name => New_Reference_To
3927 (Find_Prim_Op (Ptyp, Name_uSize), Loc),
3928 Parameter_Associations => New_List (Pref));
3930 if Typ /= Standard_Long_Long_Integer then
3932 -- The context is a specific integer type with which the
3933 -- original attribute was compatible. The function has a
3934 -- specific type as well, so to preserve the compatibility
3935 -- we must convert explicitly.
3937 New_Node := Convert_To (Typ, New_Node);
3940 Rewrite (N, New_Node);
3941 Analyze_And_Resolve (N, Typ);
3944 -- Case of known RM_Size of a type
3946 elsif (Id = Attribute_Size or else Id = Attribute_Value_Size)
3947 and then Is_Entity_Name (Pref)
3948 and then Is_Type (Entity (Pref))
3949 and then Known_Static_RM_Size (Entity (Pref))
3951 Siz := RM_Size (Entity (Pref));
3953 -- Case of known Esize of a type
3955 elsif Id = Attribute_Object_Size
3956 and then Is_Entity_Name (Pref)
3957 and then Is_Type (Entity (Pref))
3958 and then Known_Static_Esize (Entity (Pref))
3960 Siz := Esize (Entity (Pref));
3962 -- Case of known size of object
3964 elsif Id = Attribute_Size
3965 and then Is_Entity_Name (Pref)
3966 and then Is_Object (Entity (Pref))
3967 and then Known_Esize (Entity (Pref))
3968 and then Known_Static_Esize (Entity (Pref))
3970 Siz := Esize (Entity (Pref));
3972 -- For an array component, we can do Size in the front end
3973 -- if the component_size of the array is set.
3975 elsif Nkind (Pref) = N_Indexed_Component then
3976 Siz := Component_Size (Etype (Prefix (Pref)));
3978 -- For a record component, we can do Size in the front end if there
3979 -- is a component clause, or if the record is packed and the
3980 -- component's size is known at compile time.
3982 elsif Nkind (Pref) = N_Selected_Component then
3984 Rec : constant Entity_Id := Etype (Prefix (Pref));
3985 Comp : constant Entity_Id := Entity (Selector_Name (Pref));
3988 if Present (Component_Clause (Comp)) then
3989 Siz := Esize (Comp);
3991 elsif Is_Packed (Rec) then
3992 Siz := RM_Size (Ptyp);
3995 Apply_Universal_Integer_Attribute_Checks (N);
4000 -- All other cases are handled by the back end
4003 Apply_Universal_Integer_Attribute_Checks (N);
4005 -- If Size is applied to a formal parameter that is of a packed
4006 -- array subtype, then apply Size to the actual subtype.
4008 if Is_Entity_Name (Pref)
4009 and then Is_Formal (Entity (Pref))
4010 and then Is_Array_Type (Ptyp)
4011 and then Is_Packed (Ptyp)
4014 Make_Attribute_Reference (Loc,
4016 New_Occurrence_Of (Get_Actual_Subtype (Pref), Loc),
4017 Attribute_Name => Name_Size));
4018 Analyze_And_Resolve (N, Typ);
4021 -- If Size applies to a dereference of an access to unconstrained
4022 -- packed array, the back end needs to see its unconstrained
4023 -- nominal type, but also a hint to the actual constrained type.
4025 if Nkind (Pref) = N_Explicit_Dereference
4026 and then Is_Array_Type (Ptyp)
4027 and then not Is_Constrained (Ptyp)
4028 and then Is_Packed (Ptyp)
4030 Set_Actual_Designated_Subtype (Pref,
4031 Get_Actual_Subtype (Pref));
4037 -- Common processing for record and array component case
4039 if Siz /= No_Uint and then Siz /= 0 then
4041 CS : constant Boolean := Comes_From_Source (N);
4044 Rewrite (N, Make_Integer_Literal (Loc, Siz));
4046 -- This integer literal is not a static expression. We do not
4047 -- call Analyze_And_Resolve here, because this would activate
4048 -- the circuit for deciding that a static value was out of
4049 -- range, and we don't want that.
4051 -- So just manually set the type, mark the expression as non-
4052 -- static, and then ensure that the result is checked properly
4053 -- if the attribute comes from source (if it was internally
4054 -- generated, we never need a constraint check).
4057 Set_Is_Static_Expression (N, False);
4060 Apply_Constraint_Check (N, Typ);
4070 when Attribute_Storage_Pool =>
4072 Make_Type_Conversion (Loc,
4073 Subtype_Mark => New_Reference_To (Etype (N), Loc),
4074 Expression => New_Reference_To (Entity (N), Loc)));
4075 Analyze_And_Resolve (N, Typ);
4081 when Attribute_Storage_Size => Storage_Size : begin
4083 -- Access type case, always go to the root type
4085 -- The case of access types results in a value of zero for the case
4086 -- where no storage size attribute clause has been given. If a
4087 -- storage size has been given, then the attribute is converted
4088 -- to a reference to the variable used to hold this value.
4090 if Is_Access_Type (Ptyp) then
4091 if Present (Storage_Size_Variable (Root_Type (Ptyp))) then
4093 Make_Attribute_Reference (Loc,
4094 Prefix => New_Reference_To (Typ, Loc),
4095 Attribute_Name => Name_Max,
4096 Expressions => New_List (
4097 Make_Integer_Literal (Loc, 0),
4100 (Storage_Size_Variable (Root_Type (Ptyp)), Loc)))));
4102 elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then
4105 Make_Function_Call (Loc,
4109 (Etype (Associated_Storage_Pool (Root_Type (Ptyp))),
4110 Attribute_Name (N)),
4113 Parameter_Associations => New_List (
4115 (Associated_Storage_Pool (Root_Type (Ptyp)), Loc)))));
4118 Rewrite (N, Make_Integer_Literal (Loc, 0));
4121 Analyze_And_Resolve (N, Typ);
4123 -- For tasks, we retrieve the size directly from the TCB. The
4124 -- size may depend on a discriminant of the type, and therefore
4125 -- can be a per-object expression, so type-level information is
4126 -- not sufficient in general. There are four cases to consider:
4128 -- a) If the attribute appears within a task body, the designated
4129 -- TCB is obtained by a call to Self.
4131 -- b) If the prefix of the attribute is the name of a task object,
4132 -- the designated TCB is the one stored in the corresponding record.
4134 -- c) If the prefix is a task type, the size is obtained from the
4135 -- size variable created for each task type
4137 -- d) If no storage_size was specified for the type , there is no
4138 -- size variable, and the value is a system-specific default.
4141 if In_Open_Scopes (Ptyp) then
4143 -- Storage_Size (Self)
4147 Make_Function_Call (Loc,
4149 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4150 Parameter_Associations =>
4152 Make_Function_Call (Loc,
4154 New_Reference_To (RTE (RE_Self), Loc))))));
4156 elsif not Is_Entity_Name (Pref)
4157 or else not Is_Type (Entity (Pref))
4159 -- Storage_Size (Rec (Obj).Size)
4163 Make_Function_Call (Loc,
4165 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4166 Parameter_Associations =>
4168 Make_Selected_Component (Loc,
4170 Unchecked_Convert_To (
4171 Corresponding_Record_Type (Ptyp),
4172 New_Copy_Tree (Pref)),
4174 Make_Identifier (Loc, Name_uTask_Id))))));
4176 elsif Present (Storage_Size_Variable (Ptyp)) then
4178 -- Static storage size pragma given for type: retrieve value
4179 -- from its allocated storage variable.
4183 Make_Function_Call (Loc,
4184 Name => New_Occurrence_Of (
4185 RTE (RE_Adjust_Storage_Size), Loc),
4186 Parameter_Associations =>
4189 Storage_Size_Variable (Ptyp), Loc)))));
4191 -- Get system default
4195 Make_Function_Call (Loc,
4198 RTE (RE_Default_Stack_Size), Loc))));
4201 Analyze_And_Resolve (N, Typ);
4209 when Attribute_Stream_Size => Stream_Size : declare
4213 -- If we have a Stream_Size clause for this type use it, otherwise
4214 -- the Stream_Size if the size of the type.
4216 if Has_Stream_Size_Clause (Ptyp) then
4219 (Static_Integer (Expression (Stream_Size_Clause (Ptyp))));
4221 Size := UI_To_Int (Esize (Ptyp));
4224 Rewrite (N, Make_Integer_Literal (Loc, Intval => Size));
4225 Analyze_And_Resolve (N, Typ);
4232 -- 1. Deal with enumeration types with holes
4233 -- 2. For floating-point, generate call to attribute function
4234 -- 3. For other cases, deal with constraint checking
4236 when Attribute_Succ => Succ :
4238 Etyp : constant Entity_Id := Base_Type (Ptyp);
4242 -- For enumeration types with non-standard representations, we
4243 -- expand typ'Succ (x) into
4245 -- Pos_To_Rep (Rep_To_Pos (x) + 1)
4247 -- If the representation is contiguous, we compute instead
4248 -- Lit1 + Rep_to_Pos (x+1), to catch invalid representations.
4250 if Is_Enumeration_Type (Ptyp)
4251 and then Present (Enum_Pos_To_Rep (Etyp))
4253 if Has_Contiguous_Rep (Etyp) then
4255 Unchecked_Convert_To (Ptyp,
4258 Make_Integer_Literal (Loc,
4259 Enumeration_Rep (First_Literal (Ptyp))),
4261 Make_Function_Call (Loc,
4264 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4266 Parameter_Associations =>
4268 Unchecked_Convert_To (Ptyp,
4271 Unchecked_Convert_To (Standard_Integer,
4272 Relocate_Node (First (Exprs))),
4274 Make_Integer_Literal (Loc, 1))),
4275 Rep_To_Pos_Flag (Ptyp, Loc))))));
4277 -- Add Boolean parameter True, to request program errror if
4278 -- we have a bad representation on our hands. Add False if
4279 -- checks are suppressed.
4281 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
4283 Make_Indexed_Component (Loc,
4286 (Enum_Pos_To_Rep (Etyp), Loc),
4287 Expressions => New_List (
4290 Make_Function_Call (Loc,
4293 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4294 Parameter_Associations => Exprs),
4295 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
4298 Analyze_And_Resolve (N, Typ);
4300 -- For floating-point, we transform 'Succ into a call to the Succ
4301 -- floating-point attribute function in Fat_xxx (xxx is root type)
4303 elsif Is_Floating_Point_Type (Ptyp) then
4304 Expand_Fpt_Attribute_R (N);
4305 Analyze_And_Resolve (N, Typ);
4307 -- For modular types, nothing to do (no overflow, since wraps)
4309 elsif Is_Modular_Integer_Type (Ptyp) then
4312 -- For other types, if range checking is enabled, we must generate
4313 -- a check if overflow checking is enabled.
4315 elsif not Overflow_Checks_Suppressed (Ptyp) then
4316 Expand_Pred_Succ (N);
4324 -- Transforms X'Tag into a direct reference to the tag of X
4326 when Attribute_Tag => Tag :
4329 Prefix_Is_Type : Boolean;
4332 if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then
4333 Ttyp := Entity (Pref);
4334 Prefix_Is_Type := True;
4337 Prefix_Is_Type := False;
4340 if Is_Class_Wide_Type (Ttyp) then
4341 Ttyp := Root_Type (Ttyp);
4344 Ttyp := Underlying_Type (Ttyp);
4346 -- Ada 2005: The type may be a synchronized tagged type, in which
4347 -- case the tag information is stored in the corresponding record.
4349 if Is_Concurrent_Type (Ttyp) then
4350 Ttyp := Corresponding_Record_Type (Ttyp);
4353 if Prefix_Is_Type then
4355 -- For VMs we leave the type attribute unexpanded because
4356 -- there's not a dispatching table to reference.
4358 if VM_Target = No_VM then
4360 Unchecked_Convert_To (RTE (RE_Tag),
4362 (Node (First_Elmt (Access_Disp_Table (Ttyp))), Loc)));
4363 Analyze_And_Resolve (N, RTE (RE_Tag));
4366 -- Ada 2005 (AI-251): The use of 'Tag in the sources always
4367 -- references the primary tag of the actual object. If 'Tag is
4368 -- applied to class-wide interface objects we generate code that
4369 -- displaces "this" to reference the base of the object.
4371 elsif Comes_From_Source (N)
4372 and then Is_Class_Wide_Type (Etype (Prefix (N)))
4373 and then Is_Interface (Etype (Prefix (N)))
4376 -- (To_Tag_Ptr (Prefix'Address)).all
4378 -- Note that Prefix'Address is recursively expanded into a call
4379 -- to Base_Address (Obj.Tag)
4381 -- Not needed for VM targets, since all handled by the VM
4383 if VM_Target = No_VM then
4385 Make_Explicit_Dereference (Loc,
4386 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
4387 Make_Attribute_Reference (Loc,
4388 Prefix => Relocate_Node (Pref),
4389 Attribute_Name => Name_Address))));
4390 Analyze_And_Resolve (N, RTE (RE_Tag));
4395 Make_Selected_Component (Loc,
4396 Prefix => Relocate_Node (Pref),
4398 New_Reference_To (First_Tag_Component (Ttyp), Loc)));
4399 Analyze_And_Resolve (N, RTE (RE_Tag));
4407 -- Transforms 'Terminated attribute into a call to Terminated function
4409 when Attribute_Terminated => Terminated :
4411 -- The prefix of Terminated is of a task interface class-wide type.
4413 -- terminated (Task_Id (Pref._disp_get_task_id));
4415 if Ada_Version >= Ada_05
4416 and then Ekind (Ptyp) = E_Class_Wide_Type
4417 and then Is_Interface (Ptyp)
4418 and then Is_Task_Interface (Ptyp)
4421 Make_Function_Call (Loc,
4423 New_Reference_To (RTE (RE_Terminated), Loc),
4424 Parameter_Associations => New_List (
4425 Make_Unchecked_Type_Conversion (Loc,
4427 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
4429 Make_Selected_Component (Loc,
4431 New_Copy_Tree (Pref),
4433 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
4435 elsif Restricted_Profile then
4437 Build_Call_With_Task (Pref, RTE (RE_Restricted_Terminated)));
4441 Build_Call_With_Task (Pref, RTE (RE_Terminated)));
4444 Analyze_And_Resolve (N, Standard_Boolean);
4451 -- Transforms System'To_Address (X) into unchecked conversion
4452 -- from (integral) type of X to type address.
4454 when Attribute_To_Address =>
4456 Unchecked_Convert_To (RTE (RE_Address),
4457 Relocate_Node (First (Exprs))));
4458 Analyze_And_Resolve (N, RTE (RE_Address));
4464 when Attribute_To_Any => To_Any : declare
4465 P_Type : constant Entity_Id := Etype (Pref);
4466 Decls : constant List_Id := New_List;
4470 (Convert_To (P_Type,
4471 Relocate_Node (First (Exprs))), Decls));
4472 Insert_Actions (N, Decls);
4473 Analyze_And_Resolve (N, RTE (RE_Any));
4480 -- Transforms 'Truncation into a call to the floating-point attribute
4481 -- function Truncation in Fat_xxx (where xxx is the root type).
4482 -- Expansion is avoided for cases the back end can handle directly.
4484 when Attribute_Truncation =>
4485 if not Is_Inline_Floating_Point_Attribute (N) then
4486 Expand_Fpt_Attribute_R (N);
4493 when Attribute_TypeCode => TypeCode : declare
4494 P_Type : constant Entity_Id := Etype (Pref);
4495 Decls : constant List_Id := New_List;
4497 Rewrite (N, Build_TypeCode_Call (Loc, P_Type, Decls));
4498 Insert_Actions (N, Decls);
4499 Analyze_And_Resolve (N, RTE (RE_TypeCode));
4502 -----------------------
4503 -- Unbiased_Rounding --
4504 -----------------------
4506 -- Transforms 'Unbiased_Rounding into a call to the floating-point
4507 -- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the
4508 -- root type). Expansion is avoided for cases the back end can handle
4511 when Attribute_Unbiased_Rounding =>
4512 if not Is_Inline_Floating_Point_Attribute (N) then
4513 Expand_Fpt_Attribute_R (N);
4520 when Attribute_UET_Address => UET_Address : declare
4521 Ent : constant Entity_Id :=
4522 Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
4526 Make_Object_Declaration (Loc,
4527 Defining_Identifier => Ent,
4528 Aliased_Present => True,
4529 Object_Definition =>
4530 New_Occurrence_Of (RTE (RE_Address), Loc)));
4532 -- Construct name __gnat_xxx__SDP, where xxx is the unit name
4533 -- in normal external form.
4535 Get_External_Unit_Name_String (Get_Unit_Name (Pref));
4536 Name_Buffer (1 + 7 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
4537 Name_Len := Name_Len + 7;
4538 Name_Buffer (1 .. 7) := "__gnat_";
4539 Name_Buffer (Name_Len + 1 .. Name_Len + 5) := "__SDP";
4540 Name_Len := Name_Len + 5;
4542 Set_Is_Imported (Ent);
4543 Set_Interface_Name (Ent,
4544 Make_String_Literal (Loc,
4545 Strval => String_From_Name_Buffer));
4547 -- Set entity as internal to ensure proper Sprint output of its
4548 -- implicit importation.
4550 Set_Is_Internal (Ent);
4553 Make_Attribute_Reference (Loc,
4554 Prefix => New_Occurrence_Of (Ent, Loc),
4555 Attribute_Name => Name_Address));
4557 Analyze_And_Resolve (N, Typ);
4564 -- The processing for VADS_Size is shared with Size
4570 -- For enumeration types with a standard representation, and for all
4571 -- other types, Val is handled by the back end. For enumeration types
4572 -- with a non-standard representation we use the _Pos_To_Rep array that
4573 -- was created when the type was frozen.
4575 when Attribute_Val => Val :
4577 Etyp : constant Entity_Id := Base_Type (Entity (Pref));
4580 if Is_Enumeration_Type (Etyp)
4581 and then Present (Enum_Pos_To_Rep (Etyp))
4583 if Has_Contiguous_Rep (Etyp) then
4585 Rep_Node : constant Node_Id :=
4586 Unchecked_Convert_To (Etyp,
4589 Make_Integer_Literal (Loc,
4590 Enumeration_Rep (First_Literal (Etyp))),
4592 (Convert_To (Standard_Integer,
4593 Relocate_Node (First (Exprs))))));
4597 Unchecked_Convert_To (Etyp,
4600 Make_Integer_Literal (Loc,
4601 Enumeration_Rep (First_Literal (Etyp))),
4603 Make_Function_Call (Loc,
4606 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4607 Parameter_Associations => New_List (
4609 Rep_To_Pos_Flag (Etyp, Loc))))));
4614 Make_Indexed_Component (Loc,
4615 Prefix => New_Reference_To (Enum_Pos_To_Rep (Etyp), Loc),
4616 Expressions => New_List (
4617 Convert_To (Standard_Integer,
4618 Relocate_Node (First (Exprs))))));
4621 Analyze_And_Resolve (N, Typ);
4629 -- The code for valid is dependent on the particular types involved.
4630 -- See separate sections below for the generated code in each case.
4632 when Attribute_Valid => Valid :
4634 Btyp : Entity_Id := Base_Type (Ptyp);
4637 Save_Validity_Checks_On : constant Boolean := Validity_Checks_On;
4638 -- Save the validity checking mode. We always turn off validity
4639 -- checking during process of 'Valid since this is one place
4640 -- where we do not want the implicit validity checks to intefere
4641 -- with the explicit validity check that the programmer is doing.
4643 function Make_Range_Test return Node_Id;
4644 -- Build the code for a range test of the form
4645 -- Btyp!(Pref) >= Btyp!(Ptyp'First)
4647 -- Btyp!(Pref) <= Btyp!(Ptyp'Last)
4649 ---------------------
4650 -- Make_Range_Test --
4651 ---------------------
4653 function Make_Range_Test return Node_Id is
4660 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
4663 Unchecked_Convert_To (Btyp,
4664 Make_Attribute_Reference (Loc,
4665 Prefix => New_Occurrence_Of (Ptyp, Loc),
4666 Attribute_Name => Name_First))),
4671 Unchecked_Convert_To (Btyp,
4672 Duplicate_Subexpr_No_Checks (Pref)),
4675 Unchecked_Convert_To (Btyp,
4676 Make_Attribute_Reference (Loc,
4677 Prefix => New_Occurrence_Of (Ptyp, Loc),
4678 Attribute_Name => Name_Last))));
4679 end Make_Range_Test;
4681 -- Start of processing for Attribute_Valid
4684 -- Turn off validity checks. We do not want any implicit validity
4685 -- checks to intefere with the explicit check from the attribute
4687 Validity_Checks_On := False;
4689 -- Floating-point case. This case is handled by the Valid attribute
4690 -- code in the floating-point attribute run-time library.
4692 if Is_Floating_Point_Type (Ptyp) then
4698 -- For vax fpt types, call appropriate routine in special vax
4699 -- floating point unit. We do not have to worry about loads in
4700 -- this case, since these types have no signalling NaN's.
4702 if Vax_Float (Btyp) then
4703 Expand_Vax_Valid (N);
4705 -- The AAMP back end handles Valid for floating-point types
4707 elsif Is_AAMP_Float (Btyp) then
4708 Analyze_And_Resolve (Pref, Ptyp);
4709 Set_Etype (N, Standard_Boolean);
4712 -- Non VAX float case
4715 Find_Fat_Info (Ptyp, Ftp, Pkg);
4717 -- If the floating-point object might be unaligned, we need
4718 -- to call the special routine Unaligned_Valid, which makes
4719 -- the needed copy, being careful not to load the value into
4720 -- any floating-point register. The argument in this case is
4721 -- obj'Address (see Unaligned_Valid routine in Fat_Gen).
4723 if Is_Possibly_Unaligned_Object (Pref) then
4724 Expand_Fpt_Attribute
4725 (N, Pkg, Name_Unaligned_Valid,
4727 Make_Attribute_Reference (Loc,
4728 Prefix => Relocate_Node (Pref),
4729 Attribute_Name => Name_Address)));
4731 -- In the normal case where we are sure the object is
4732 -- aligned, we generate a call to Valid, and the argument in
4733 -- this case is obj'Unrestricted_Access (after converting
4734 -- obj to the right floating-point type).
4737 Expand_Fpt_Attribute
4738 (N, Pkg, Name_Valid,
4740 Make_Attribute_Reference (Loc,
4741 Prefix => Unchecked_Convert_To (Ftp, Pref),
4742 Attribute_Name => Name_Unrestricted_Access)));
4746 -- One more task, we still need a range check. Required
4747 -- only if we have a constraint, since the Valid routine
4748 -- catches infinities properly (infinities are never valid).
4750 -- The way we do the range check is simply to create the
4751 -- expression: Valid (N) and then Base_Type(Pref) in Typ.
4753 if not Subtypes_Statically_Match (Ptyp, Btyp) then
4756 Left_Opnd => Relocate_Node (N),
4759 Left_Opnd => Convert_To (Btyp, Pref),
4760 Right_Opnd => New_Occurrence_Of (Ptyp, Loc))));
4764 -- Enumeration type with holes
4766 -- For enumeration types with holes, the Pos value constructed by
4767 -- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a
4768 -- second argument of False returns minus one for an invalid value,
4769 -- and the non-negative pos value for a valid value, so the
4770 -- expansion of X'Valid is simply:
4772 -- type(X)'Pos (X) >= 0
4774 -- We can't quite generate it that way because of the requirement
4775 -- for the non-standard second argument of False in the resulting
4776 -- rep_to_pos call, so we have to explicitly create:
4778 -- _rep_to_pos (X, False) >= 0
4780 -- If we have an enumeration subtype, we also check that the
4781 -- value is in range:
4783 -- _rep_to_pos (X, False) >= 0
4785 -- (X >= type(X)'First and then type(X)'Last <= X)
4787 elsif Is_Enumeration_Type (Ptyp)
4788 and then Present (Enum_Pos_To_Rep (Base_Type (Ptyp)))
4793 Make_Function_Call (Loc,
4796 (TSS (Base_Type (Ptyp), TSS_Rep_To_Pos), Loc),
4797 Parameter_Associations => New_List (
4799 New_Occurrence_Of (Standard_False, Loc))),
4800 Right_Opnd => Make_Integer_Literal (Loc, 0));
4804 (Type_Low_Bound (Ptyp) /= Type_Low_Bound (Btyp)
4806 Type_High_Bound (Ptyp) /= Type_High_Bound (Btyp))
4808 -- The call to Make_Range_Test will create declarations
4809 -- that need a proper insertion point, but Pref is now
4810 -- attached to a node with no ancestor. Attach to tree
4811 -- even if it is to be rewritten below.
4813 Set_Parent (Tst, Parent (N));
4817 Left_Opnd => Make_Range_Test,
4823 -- Fortran convention booleans
4825 -- For the very special case of Fortran convention booleans, the
4826 -- value is always valid, since it is an integer with the semantics
4827 -- that non-zero is true, and any value is permissible.
4829 elsif Is_Boolean_Type (Ptyp)
4830 and then Convention (Ptyp) = Convention_Fortran
4832 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
4834 -- For biased representations, we will be doing an unchecked
4835 -- conversion without unbiasing the result. That means that the range
4836 -- test has to take this into account, and the proper form of the
4839 -- Btyp!(Pref) < Btyp!(Ptyp'Range_Length)
4841 elsif Has_Biased_Representation (Ptyp) then
4842 Btyp := RTE (RE_Unsigned_32);
4846 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
4848 Unchecked_Convert_To (Btyp,
4849 Make_Attribute_Reference (Loc,
4850 Prefix => New_Occurrence_Of (Ptyp, Loc),
4851 Attribute_Name => Name_Range_Length))));
4853 -- For all other scalar types, what we want logically is a
4856 -- X in type(X)'First .. type(X)'Last
4858 -- But that's precisely what won't work because of possible
4859 -- unwanted optimization (and indeed the basic motivation for
4860 -- the Valid attribute is exactly that this test does not work!)
4861 -- What will work is:
4863 -- Btyp!(X) >= Btyp!(type(X)'First)
4865 -- Btyp!(X) <= Btyp!(type(X)'Last)
4867 -- where Btyp is an integer type large enough to cover the full
4868 -- range of possible stored values (i.e. it is chosen on the basis
4869 -- of the size of the type, not the range of the values). We write
4870 -- this as two tests, rather than a range check, so that static
4871 -- evaluation will easily remove either or both of the checks if
4872 -- they can be -statically determined to be true (this happens
4873 -- when the type of X is static and the range extends to the full
4874 -- range of stored values).
4876 -- Unsigned types. Note: it is safe to consider only whether the
4877 -- subtype is unsigned, since we will in that case be doing all
4878 -- unsigned comparisons based on the subtype range. Since we use the
4879 -- actual subtype object size, this is appropriate.
4881 -- For example, if we have
4883 -- subtype x is integer range 1 .. 200;
4884 -- for x'Object_Size use 8;
4886 -- Now the base type is signed, but objects of this type are bits
4887 -- unsigned, and doing an unsigned test of the range 1 to 200 is
4888 -- correct, even though a value greater than 127 looks signed to a
4889 -- signed comparison.
4891 elsif Is_Unsigned_Type (Ptyp) then
4892 if Esize (Ptyp) <= 32 then
4893 Btyp := RTE (RE_Unsigned_32);
4895 Btyp := RTE (RE_Unsigned_64);
4898 Rewrite (N, Make_Range_Test);
4903 if Esize (Ptyp) <= Esize (Standard_Integer) then
4904 Btyp := Standard_Integer;
4906 Btyp := Universal_Integer;
4909 Rewrite (N, Make_Range_Test);
4912 Analyze_And_Resolve (N, Standard_Boolean);
4913 Validity_Checks_On := Save_Validity_Checks_On;
4920 -- Value attribute is handled in separate unti Exp_Imgv
4922 when Attribute_Value =>
4923 Exp_Imgv.Expand_Value_Attribute (N);
4929 -- The processing for Value_Size shares the processing for Size
4935 -- The processing for Version shares the processing for Body_Version
4941 -- Wide_Image attribute is handled in separate unit Exp_Imgv
4943 when Attribute_Wide_Image =>
4944 Exp_Imgv.Expand_Wide_Image_Attribute (N);
4946 ---------------------
4947 -- Wide_Wide_Image --
4948 ---------------------
4950 -- Wide_Wide_Image attribute is handled in separate unit Exp_Imgv
4952 when Attribute_Wide_Wide_Image =>
4953 Exp_Imgv.Expand_Wide_Wide_Image_Attribute (N);
4959 -- We expand typ'Wide_Value (X) into
4962 -- (Wide_String_To_String (X, Wide_Character_Encoding_Method))
4964 -- Wide_String_To_String is a runtime function that converts its wide
4965 -- string argument to String, converting any non-translatable characters
4966 -- into appropriate escape sequences. This preserves the required
4967 -- semantics of Wide_Value in all cases, and results in a very simple
4968 -- implementation approach.
4970 -- Note: for this approach to be fully standard compliant for the cases
4971 -- where typ is Wide_Character and Wide_Wide_Character, the encoding
4972 -- method must cover the entire character range (e.g. UTF-8). But that
4973 -- is a reasonable requirement when dealing with encoded character
4974 -- sequences. Presumably if one of the restrictive encoding mechanisms
4975 -- is in use such as Shift-JIS, then characters that cannot be
4976 -- represented using this encoding will not appear in any case.
4978 when Attribute_Wide_Value => Wide_Value :
4981 Make_Attribute_Reference (Loc,
4983 Attribute_Name => Name_Value,
4985 Expressions => New_List (
4986 Make_Function_Call (Loc,
4988 New_Reference_To (RTE (RE_Wide_String_To_String), Loc),
4990 Parameter_Associations => New_List (
4991 Relocate_Node (First (Exprs)),
4992 Make_Integer_Literal (Loc,
4993 Intval => Int (Wide_Character_Encoding_Method)))))));
4995 Analyze_And_Resolve (N, Typ);
4998 ---------------------
4999 -- Wide_Wide_Value --
5000 ---------------------
5002 -- We expand typ'Wide_Value_Value (X) into
5005 -- (Wide_Wide_String_To_String (X, Wide_Character_Encoding_Method))
5007 -- Wide_Wide_String_To_String is a runtime function that converts its
5008 -- wide string argument to String, converting any non-translatable
5009 -- characters into appropriate escape sequences. This preserves the
5010 -- required semantics of Wide_Wide_Value in all cases, and results in a
5011 -- very simple implementation approach.
5013 -- It's not quite right where typ = Wide_Wide_Character, because the
5014 -- encoding method may not cover the whole character type ???
5016 when Attribute_Wide_Wide_Value => Wide_Wide_Value :
5019 Make_Attribute_Reference (Loc,
5021 Attribute_Name => Name_Value,
5023 Expressions => New_List (
5024 Make_Function_Call (Loc,
5026 New_Reference_To (RTE (RE_Wide_Wide_String_To_String), Loc),
5028 Parameter_Associations => New_List (
5029 Relocate_Node (First (Exprs)),
5030 Make_Integer_Literal (Loc,
5031 Intval => Int (Wide_Character_Encoding_Method)))))));
5033 Analyze_And_Resolve (N, Typ);
5034 end Wide_Wide_Value;
5036 ---------------------
5037 -- Wide_Wide_Width --
5038 ---------------------
5040 -- Wide_Wide_Width attribute is handled in separate unit Exp_Imgv
5042 when Attribute_Wide_Wide_Width =>
5043 Exp_Imgv.Expand_Width_Attribute (N, Wide_Wide);
5049 -- Wide_Width attribute is handled in separate unit Exp_Imgv
5051 when Attribute_Wide_Width =>
5052 Exp_Imgv.Expand_Width_Attribute (N, Wide);
5058 -- Width attribute is handled in separate unit Exp_Imgv
5060 when Attribute_Width =>
5061 Exp_Imgv.Expand_Width_Attribute (N, Normal);
5067 when Attribute_Write => Write : declare
5068 P_Type : constant Entity_Id := Entity (Pref);
5069 U_Type : constant Entity_Id := Underlying_Type (P_Type);
5077 -- If no underlying type, we have an error that will be diagnosed
5078 -- elsewhere, so here we just completely ignore the expansion.
5084 -- The simple case, if there is a TSS for Write, just call it
5086 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Write);
5088 if Present (Pname) then
5092 -- If there is a Stream_Convert pragma, use it, we rewrite
5094 -- sourcetyp'Output (stream, Item)
5098 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
5100 -- where strmwrite is the given Write function that converts an
5101 -- argument of type sourcetyp or a type acctyp, from which it is
5102 -- derived to type strmtyp. The conversion to acttyp is required
5103 -- for the derived case.
5105 Prag := Get_Stream_Convert_Pragma (P_Type);
5107 if Present (Prag) then
5109 Next (Next (First (Pragma_Argument_Associations (Prag))));
5110 Wfunc := Entity (Expression (Arg3));
5113 Make_Attribute_Reference (Loc,
5114 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
5115 Attribute_Name => Name_Output,
5116 Expressions => New_List (
5117 Relocate_Node (First (Exprs)),
5118 Make_Function_Call (Loc,
5119 Name => New_Occurrence_Of (Wfunc, Loc),
5120 Parameter_Associations => New_List (
5121 OK_Convert_To (Etype (First_Formal (Wfunc)),
5122 Relocate_Node (Next (First (Exprs)))))))));
5127 -- For elementary types, we call the W_xxx routine directly
5129 elsif Is_Elementary_Type (U_Type) then
5130 Rewrite (N, Build_Elementary_Write_Call (N));
5136 elsif Is_Array_Type (U_Type) then
5137 Build_Array_Write_Procedure (N, U_Type, Decl, Pname);
5138 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
5140 -- Tagged type case, use the primitive Write function. Note that
5141 -- this will dispatch in the class-wide case which is what we want
5143 elsif Is_Tagged_Type (U_Type) then
5144 Pname := Find_Prim_Op (U_Type, TSS_Stream_Write);
5146 -- All other record type cases, including protected records.
5147 -- The latter only arise for expander generated code for
5148 -- handling shared passive partition access.
5152 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
5154 -- Ada 2005 (AI-216): Program_Error is raised when executing
5155 -- the default implementation of the Write attribute of an
5156 -- Unchecked_Union type. However, if the 'Write reference is
5157 -- within the generated Output stream procedure, Write outputs
5158 -- the components, and the default values of the discriminant
5159 -- are streamed by the Output procedure itself.
5161 if Is_Unchecked_Union (Base_Type (U_Type))
5162 and not Is_TSS (Current_Scope, TSS_Stream_Output)
5165 Make_Raise_Program_Error (Loc,
5166 Reason => PE_Unchecked_Union_Restriction));
5169 if Has_Discriminants (U_Type)
5171 (Discriminant_Default_Value (First_Discriminant (U_Type)))
5173 Build_Mutable_Record_Write_Procedure
5174 (Loc, Base_Type (U_Type), Decl, Pname);
5176 Build_Record_Write_Procedure
5177 (Loc, Base_Type (U_Type), Decl, Pname);
5180 Insert_Action (N, Decl);
5184 -- If we fall through, Pname is the procedure to be called
5186 Rewrite_Stream_Proc_Call (Pname);
5189 -- Component_Size is handled by the back end, unless the component size
5190 -- is known at compile time, which is always true in the packed array
5191 -- case. It is important that the packed array case is handled in the
5192 -- front end (see Eval_Attribute) since the back end would otherwise get
5193 -- confused by the equivalent packed array type.
5195 when Attribute_Component_Size =>
5198 -- The following attributes are handled by the back end (except that
5199 -- static cases have already been evaluated during semantic processing,
5200 -- but in any case the back end should not count on this). The one bit
5201 -- of special processing required is that these attributes typically
5202 -- generate conditionals in the code, so we need to check the relevant
5205 when Attribute_Max |
5207 Check_Restriction (No_Implicit_Conditionals, N);
5209 -- The following attributes are handled by the back end (except that
5210 -- static cases have already been evaluated during semantic processing,
5211 -- but in any case the back end should not count on this).
5213 -- The back end also handles the non-class-wide cases of Size
5215 when Attribute_Bit_Order |
5216 Attribute_Code_Address |
5217 Attribute_Definite |
5218 Attribute_Null_Parameter |
5219 Attribute_Passed_By_Reference |
5220 Attribute_Pool_Address =>
5223 -- The following attributes are also handled by the back end, but return
5224 -- a universal integer result, so may need a conversion for checking
5225 -- that the result is in range.
5227 when Attribute_Aft |
5229 Attribute_Max_Size_In_Storage_Elements
5231 Apply_Universal_Integer_Attribute_Checks (N);
5233 -- The following attributes should not appear at this stage, since they
5234 -- have already been handled by the analyzer (and properly rewritten
5235 -- with corresponding values or entities to represent the right values)
5237 when Attribute_Abort_Signal |
5238 Attribute_Address_Size |
5241 Attribute_Default_Bit_Order |
5248 Attribute_Fast_Math |
5249 Attribute_Has_Access_Values |
5250 Attribute_Has_Discriminants |
5251 Attribute_Has_Tagged_Values |
5253 Attribute_Machine_Emax |
5254 Attribute_Machine_Emin |
5255 Attribute_Machine_Mantissa |
5256 Attribute_Machine_Overflows |
5257 Attribute_Machine_Radix |
5258 Attribute_Machine_Rounds |
5259 Attribute_Maximum_Alignment |
5260 Attribute_Model_Emin |
5261 Attribute_Model_Epsilon |
5262 Attribute_Model_Mantissa |
5263 Attribute_Model_Small |
5265 Attribute_Partition_ID |
5267 Attribute_Safe_Emax |
5268 Attribute_Safe_First |
5269 Attribute_Safe_Large |
5270 Attribute_Safe_Last |
5271 Attribute_Safe_Small |
5273 Attribute_Signed_Zeros |
5275 Attribute_Storage_Unit |
5276 Attribute_Stub_Type |
5277 Attribute_Target_Name |
5278 Attribute_Type_Class |
5279 Attribute_Unconstrained_Array |
5280 Attribute_Universal_Literal_String |
5281 Attribute_Wchar_T_Size |
5282 Attribute_Word_Size =>
5284 raise Program_Error;
5286 -- The Asm_Input and Asm_Output attributes are not expanded at this
5287 -- stage, but will be eliminated in the expansion of the Asm call, see
5288 -- Exp_Intr for details. So the back end will never see these either.
5290 when Attribute_Asm_Input |
5291 Attribute_Asm_Output =>
5298 when RE_Not_Available =>
5300 end Expand_N_Attribute_Reference;
5302 ----------------------
5303 -- Expand_Pred_Succ --
5304 ----------------------
5306 -- For typ'Pred (exp), we generate the check
5308 -- [constraint_error when exp = typ'Base'First]
5310 -- Similarly, for typ'Succ (exp), we generate the check
5312 -- [constraint_error when exp = typ'Base'Last]
5314 -- These checks are not generated for modular types, since the proper
5315 -- semantics for Succ and Pred on modular types is to wrap, not raise CE.
5317 procedure Expand_Pred_Succ (N : Node_Id) is
5318 Loc : constant Source_Ptr := Sloc (N);
5322 if Attribute_Name (N) = Name_Pred then
5329 Make_Raise_Constraint_Error (Loc,
5333 Duplicate_Subexpr_Move_Checks (First (Expressions (N))),
5335 Make_Attribute_Reference (Loc,
5337 New_Reference_To (Base_Type (Etype (Prefix (N))), Loc),
5338 Attribute_Name => Cnam)),
5339 Reason => CE_Overflow_Check_Failed));
5340 end Expand_Pred_Succ;
5346 procedure Find_Fat_Info
5348 Fat_Type : out Entity_Id;
5349 Fat_Pkg : out RE_Id)
5351 Btyp : constant Entity_Id := Base_Type (T);
5352 Rtyp : constant Entity_Id := Root_Type (T);
5353 Digs : constant Nat := UI_To_Int (Digits_Value (Btyp));
5356 -- If the base type is VAX float, then get appropriate VAX float type
5358 if Vax_Float (Btyp) then
5361 Fat_Type := RTE (RE_Fat_VAX_F);
5362 Fat_Pkg := RE_Attr_VAX_F_Float;
5365 Fat_Type := RTE (RE_Fat_VAX_D);
5366 Fat_Pkg := RE_Attr_VAX_D_Float;
5369 Fat_Type := RTE (RE_Fat_VAX_G);
5370 Fat_Pkg := RE_Attr_VAX_G_Float;
5373 raise Program_Error;
5376 -- If root type is VAX float, this is the case where the library has
5377 -- been recompiled in VAX float mode, and we have an IEEE float type.
5378 -- This is when we use the special IEEE Fat packages.
5380 elsif Vax_Float (Rtyp) then
5383 Fat_Type := RTE (RE_Fat_IEEE_Short);
5384 Fat_Pkg := RE_Attr_IEEE_Short;
5387 Fat_Type := RTE (RE_Fat_IEEE_Long);
5388 Fat_Pkg := RE_Attr_IEEE_Long;
5391 raise Program_Error;
5394 -- If neither the base type nor the root type is VAX_Float then VAX
5395 -- float is out of the picture, and we can just use the root type.
5400 if Fat_Type = Standard_Short_Float then
5401 Fat_Pkg := RE_Attr_Short_Float;
5403 elsif Fat_Type = Standard_Float then
5404 Fat_Pkg := RE_Attr_Float;
5406 elsif Fat_Type = Standard_Long_Float then
5407 Fat_Pkg := RE_Attr_Long_Float;
5409 elsif Fat_Type = Standard_Long_Long_Float then
5410 Fat_Pkg := RE_Attr_Long_Long_Float;
5412 -- Universal real (which is its own root type) is treated as being
5413 -- equivalent to Standard.Long_Long_Float, since it is defined to
5414 -- have the same precision as the longest Float type.
5416 elsif Fat_Type = Universal_Real then
5417 Fat_Type := Standard_Long_Long_Float;
5418 Fat_Pkg := RE_Attr_Long_Long_Float;
5421 raise Program_Error;
5426 ----------------------------
5427 -- Find_Stream_Subprogram --
5428 ----------------------------
5430 function Find_Stream_Subprogram
5432 Nam : TSS_Name_Type) return Entity_Id
5434 Base_Typ : constant Entity_Id := Base_Type (Typ);
5435 Ent : constant Entity_Id := TSS (Typ, Nam);
5438 if Present (Ent) then
5442 -- Stream attributes for strings are expanded into library calls. The
5443 -- following checks are disabled when the run-time is not available or
5444 -- when compiling predefined types due to bootstrap issues. As a result,
5445 -- the compiler will generate in-place stream routines for string types
5446 -- that appear in GNAT's library, but will generate calls via rtsfind
5447 -- to library routines for user code.
5448 -- ??? For now, disable this code for JVM, since this generates a
5449 -- VerifyError exception at run-time on e.g. c330001.
5450 -- This is disabled for AAMP, to avoid making dependences on files not
5451 -- supported in the AAMP library (such as s-fileio.adb).
5453 if VM_Target /= JVM_Target
5454 and then not AAMP_On_Target
5456 not Is_Predefined_File_Name (Unit_File_Name (Current_Sem_Unit))
5458 -- String as defined in package Ada
5460 if Base_Typ = Standard_String then
5461 if Restriction_Active (No_Stream_Optimizations) then
5462 if Nam = TSS_Stream_Input then
5463 return RTE (RE_String_Input);
5465 elsif Nam = TSS_Stream_Output then
5466 return RTE (RE_String_Output);
5468 elsif Nam = TSS_Stream_Read then
5469 return RTE (RE_String_Read);
5471 else pragma Assert (Nam = TSS_Stream_Write);
5472 return RTE (RE_String_Write);
5476 if Nam = TSS_Stream_Input then
5477 return RTE (RE_String_Input_Blk_IO);
5479 elsif Nam = TSS_Stream_Output then
5480 return RTE (RE_String_Output_Blk_IO);
5482 elsif Nam = TSS_Stream_Read then
5483 return RTE (RE_String_Read_Blk_IO);
5485 else pragma Assert (Nam = TSS_Stream_Write);
5486 return RTE (RE_String_Write_Blk_IO);
5490 -- Wide_String as defined in package Ada
5492 elsif Base_Typ = Standard_Wide_String then
5493 if Restriction_Active (No_Stream_Optimizations) then
5494 if Nam = TSS_Stream_Input then
5495 return RTE (RE_Wide_String_Input);
5497 elsif Nam = TSS_Stream_Output then
5498 return RTE (RE_Wide_String_Output);
5500 elsif Nam = TSS_Stream_Read then
5501 return RTE (RE_Wide_String_Read);
5503 else pragma Assert (Nam = TSS_Stream_Write);
5504 return RTE (RE_Wide_String_Write);
5508 if Nam = TSS_Stream_Input then
5509 return RTE (RE_Wide_String_Input_Blk_IO);
5511 elsif Nam = TSS_Stream_Output then
5512 return RTE (RE_Wide_String_Output_Blk_IO);
5514 elsif Nam = TSS_Stream_Read then
5515 return RTE (RE_Wide_String_Read_Blk_IO);
5517 else pragma Assert (Nam = TSS_Stream_Write);
5518 return RTE (RE_Wide_String_Write_Blk_IO);
5522 -- Wide_Wide_String as defined in package Ada
5524 elsif Base_Typ = Standard_Wide_Wide_String then
5525 if Restriction_Active (No_Stream_Optimizations) then
5526 if Nam = TSS_Stream_Input then
5527 return RTE (RE_Wide_Wide_String_Input);
5529 elsif Nam = TSS_Stream_Output then
5530 return RTE (RE_Wide_Wide_String_Output);
5532 elsif Nam = TSS_Stream_Read then
5533 return RTE (RE_Wide_Wide_String_Read);
5535 else pragma Assert (Nam = TSS_Stream_Write);
5536 return RTE (RE_Wide_Wide_String_Write);
5540 if Nam = TSS_Stream_Input then
5541 return RTE (RE_Wide_Wide_String_Input_Blk_IO);
5543 elsif Nam = TSS_Stream_Output then
5544 return RTE (RE_Wide_Wide_String_Output_Blk_IO);
5546 elsif Nam = TSS_Stream_Read then
5547 return RTE (RE_Wide_Wide_String_Read_Blk_IO);
5549 else pragma Assert (Nam = TSS_Stream_Write);
5550 return RTE (RE_Wide_Wide_String_Write_Blk_IO);
5556 if Is_Tagged_Type (Typ)
5557 and then Is_Derived_Type (Typ)
5559 return Find_Prim_Op (Typ, Nam);
5561 return Find_Inherited_TSS (Typ, Nam);
5563 end Find_Stream_Subprogram;
5565 -----------------------
5566 -- Get_Index_Subtype --
5567 -----------------------
5569 function Get_Index_Subtype (N : Node_Id) return Node_Id is
5570 P_Type : Entity_Id := Etype (Prefix (N));
5575 if Is_Access_Type (P_Type) then
5576 P_Type := Designated_Type (P_Type);
5579 if No (Expressions (N)) then
5582 J := UI_To_Int (Expr_Value (First (Expressions (N))));
5585 Indx := First_Index (P_Type);
5591 return Etype (Indx);
5592 end Get_Index_Subtype;
5594 -------------------------------
5595 -- Get_Stream_Convert_Pragma --
5596 -------------------------------
5598 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id is
5603 -- Note: we cannot use Get_Rep_Pragma here because of the peculiarity
5604 -- that a stream convert pragma for a tagged type is not inherited from
5605 -- its parent. Probably what is wrong here is that it is basically
5606 -- incorrect to consider a stream convert pragma to be a representation
5607 -- pragma at all ???
5609 N := First_Rep_Item (Implementation_Base_Type (T));
5610 while Present (N) loop
5611 if Nkind (N) = N_Pragma
5612 and then Pragma_Name (N) = Name_Stream_Convert
5614 -- For tagged types this pragma is not inherited, so we
5615 -- must verify that it is defined for the given type and
5619 Entity (Expression (First (Pragma_Argument_Associations (N))));
5621 if not Is_Tagged_Type (T)
5623 or else (Is_Private_Type (Typ) and then T = Full_View (Typ))
5633 end Get_Stream_Convert_Pragma;
5635 ---------------------------------
5636 -- Is_Constrained_Packed_Array --
5637 ---------------------------------
5639 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean is
5640 Arr : Entity_Id := Typ;
5643 if Is_Access_Type (Arr) then
5644 Arr := Designated_Type (Arr);
5647 return Is_Array_Type (Arr)
5648 and then Is_Constrained (Arr)
5649 and then Present (Packed_Array_Type (Arr));
5650 end Is_Constrained_Packed_Array;
5652 ----------------------------------------
5653 -- Is_Inline_Floating_Point_Attribute --
5654 ----------------------------------------
5656 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean is
5657 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
5660 if Nkind (Parent (N)) /= N_Type_Conversion
5661 or else not Is_Integer_Type (Etype (Parent (N)))
5666 -- Should also support 'Machine_Rounding and 'Unbiased_Rounding, but
5667 -- required back end support has not been implemented yet ???
5669 return Id = Attribute_Truncation;
5670 end Is_Inline_Floating_Point_Attribute;
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