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);
239 E_T : constant Entity_Id := Equivalent_Type (Btyp);
240 Acc : constant Entity_Id :=
241 Etype (Next_Component (First_Component (E_T)));
245 function May_Be_External_Call return Boolean;
246 -- If the 'Access is to a local operation, but appears in a context
247 -- where it may lead to a call from outside the object, we must treat
248 -- this as an external call. Clearly we cannot tell without full
249 -- flow analysis, and a subsequent call that uses this 'Access may
250 -- lead to a bounded error (trying to seize locks twice, e.g.). For
251 -- now we treat 'Access as a potential external call if it is an actual
252 -- in a call to an outside subprogram.
254 --------------------------
255 -- May_Be_External_Call --
256 --------------------------
258 function May_Be_External_Call return Boolean is
260 Par : Node_Id := Parent (N);
263 -- Account for the case where the Access attribute is part of a
264 -- named parameter association.
266 if Nkind (Par) = N_Parameter_Association then
270 if Nkind_In (Par, N_Procedure_Call_Statement, N_Function_Call)
271 and then Is_Entity_Name (Name (Par))
273 Subp := Entity (Name (Par));
274 return not In_Open_Scopes (Scope (Subp));
278 end May_Be_External_Call;
280 -- Start of processing for Expand_Access_To_Protected_Op
283 -- Within the body of the protected type, the prefix
284 -- designates a local operation, and the object is the first
285 -- parameter of the corresponding protected body of the
286 -- current enclosing operation.
288 if Is_Entity_Name (Pref) then
289 if May_Be_External_Call then
292 (External_Subprogram (Entity (Pref)), Loc);
296 (Protected_Body_Subprogram (Entity (Pref)), Loc);
299 -- Don't traverse the scopes when the attribute occurs within an init
300 -- proc, because we directly use the _init formal of the init proc in
303 Curr := Current_Scope;
304 if not Is_Init_Proc (Curr) then
305 pragma Assert (In_Open_Scopes (Scope (Entity (Pref))));
307 while Scope (Curr) /= Scope (Entity (Pref)) loop
308 Curr := Scope (Curr);
312 -- In case of protected entries the first formal of its Protected_
313 -- Body_Subprogram is the address of the object.
315 if Ekind (Curr) = E_Entry then
319 (Protected_Body_Subprogram (Curr)), Loc);
321 -- If the current scope is an init proc, then use the address of the
322 -- _init formal as the object reference.
324 elsif Is_Init_Proc (Curr) then
326 Make_Attribute_Reference (Loc,
327 Prefix => New_Occurrence_Of (First_Formal (Curr), Loc),
328 Attribute_Name => Name_Address);
330 -- In case of protected subprograms the first formal of its
331 -- Protected_Body_Subprogram is the object and we get its address.
335 Make_Attribute_Reference (Loc,
339 (Protected_Body_Subprogram (Curr)), Loc),
340 Attribute_Name => Name_Address);
343 -- Case where the prefix is not an entity name. Find the
344 -- version of the protected operation to be called from
345 -- outside the protected object.
351 (Entity (Selector_Name (Pref))), Loc);
354 Make_Attribute_Reference (Loc,
355 Prefix => Relocate_Node (Prefix (Pref)),
356 Attribute_Name => Name_Address);
360 Make_Attribute_Reference (Loc,
362 Attribute_Name => Name_Access);
364 -- We set the type of the access reference to the already generated
365 -- access_to_subprogram type, and declare the reference analyzed, to
366 -- prevent further expansion when the enclosing aggregate is analyzed.
368 Set_Etype (Sub_Ref, Acc);
369 Set_Analyzed (Sub_Ref);
373 Expressions => New_List (Obj_Ref, Sub_Ref));
376 Analyze_And_Resolve (N, E_T);
378 -- For subsequent analysis, the node must retain its type. The backend
379 -- will replace it with the equivalent type where needed.
382 end Expand_Access_To_Protected_Op;
384 --------------------------
385 -- Expand_Fpt_Attribute --
386 --------------------------
388 procedure Expand_Fpt_Attribute
394 Loc : constant Source_Ptr := Sloc (N);
395 Typ : constant Entity_Id := Etype (N);
399 -- The function name is the selected component Attr_xxx.yyy where
400 -- Attr_xxx is the package name, and yyy is the argument Nam.
402 -- Note: it would be more usual to have separate RE entries for each
403 -- of the entities in the Fat packages, but first they have identical
404 -- names (so we would have to have lots of renaming declarations to
405 -- meet the normal RE rule of separate names for all runtime entities),
406 -- and second there would be an awful lot of them!
409 Make_Selected_Component (Loc,
410 Prefix => New_Reference_To (RTE (Pkg), Loc),
411 Selector_Name => Make_Identifier (Loc, Nam));
413 -- The generated call is given the provided set of parameters, and then
414 -- wrapped in a conversion which converts the result to the target type
415 -- We use the base type as the target because a range check may be
419 Unchecked_Convert_To (Base_Type (Etype (N)),
420 Make_Function_Call (Loc,
422 Parameter_Associations => Args)));
424 Analyze_And_Resolve (N, Typ);
425 end Expand_Fpt_Attribute;
427 ----------------------------
428 -- Expand_Fpt_Attribute_R --
429 ----------------------------
431 -- The single argument is converted to its root type to call the
432 -- appropriate runtime function, with the actual call being built
433 -- by Expand_Fpt_Attribute
435 procedure Expand_Fpt_Attribute_R (N : Node_Id) is
436 E1 : constant Node_Id := First (Expressions (N));
440 Find_Fat_Info (Etype (E1), Ftp, Pkg);
442 (N, Pkg, Attribute_Name (N),
443 New_List (Unchecked_Convert_To (Ftp, Relocate_Node (E1))));
444 end Expand_Fpt_Attribute_R;
446 -----------------------------
447 -- Expand_Fpt_Attribute_RI --
448 -----------------------------
450 -- The first argument is converted to its root type and the second
451 -- argument is converted to standard long long integer to call the
452 -- appropriate runtime function, with the actual call being built
453 -- by Expand_Fpt_Attribute
455 procedure Expand_Fpt_Attribute_RI (N : Node_Id) is
456 E1 : constant Node_Id := First (Expressions (N));
459 E2 : constant Node_Id := Next (E1);
461 Find_Fat_Info (Etype (E1), Ftp, Pkg);
463 (N, Pkg, Attribute_Name (N),
465 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
466 Unchecked_Convert_To (Standard_Integer, Relocate_Node (E2))));
467 end Expand_Fpt_Attribute_RI;
469 -----------------------------
470 -- Expand_Fpt_Attribute_RR --
471 -----------------------------
473 -- The two arguments are converted to their root types to call the
474 -- appropriate runtime function, with the actual call being built
475 -- by Expand_Fpt_Attribute
477 procedure Expand_Fpt_Attribute_RR (N : Node_Id) is
478 E1 : constant Node_Id := First (Expressions (N));
481 E2 : constant Node_Id := Next (E1);
483 Find_Fat_Info (Etype (E1), Ftp, Pkg);
485 (N, Pkg, Attribute_Name (N),
487 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
488 Unchecked_Convert_To (Ftp, Relocate_Node (E2))));
489 end Expand_Fpt_Attribute_RR;
491 ----------------------------------
492 -- Expand_N_Attribute_Reference --
493 ----------------------------------
495 procedure Expand_N_Attribute_Reference (N : Node_Id) is
496 Loc : constant Source_Ptr := Sloc (N);
497 Typ : constant Entity_Id := Etype (N);
498 Btyp : constant Entity_Id := Base_Type (Typ);
499 Pref : constant Node_Id := Prefix (N);
500 Ptyp : constant Entity_Id := Etype (Pref);
501 Exprs : constant List_Id := Expressions (N);
502 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
504 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id);
505 -- Rewrites a stream attribute for Read, Write or Output with the
506 -- procedure call. Pname is the entity for the procedure to call.
508 ------------------------------
509 -- Rewrite_Stream_Proc_Call --
510 ------------------------------
512 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id) is
513 Item : constant Node_Id := Next (First (Exprs));
514 Formal : constant Entity_Id := Next_Formal (First_Formal (Pname));
515 Formal_Typ : constant Entity_Id := Etype (Formal);
516 Is_Written : constant Boolean := (Ekind (Formal) /= E_In_Parameter);
519 -- The expansion depends on Item, the second actual, which is
520 -- the object being streamed in or out.
522 -- If the item is a component of a packed array type, and
523 -- a conversion is needed on exit, we introduce a temporary to
524 -- hold the value, because otherwise the packed reference will
525 -- not be properly expanded.
527 if Nkind (Item) = N_Indexed_Component
528 and then Is_Packed (Base_Type (Etype (Prefix (Item))))
529 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
533 Temp : constant Entity_Id :=
534 Make_Defining_Identifier
535 (Loc, New_Internal_Name ('V'));
541 Make_Object_Declaration (Loc,
542 Defining_Identifier => Temp,
544 New_Occurrence_Of (Formal_Typ, Loc));
545 Set_Etype (Temp, Formal_Typ);
548 Make_Assignment_Statement (Loc,
549 Name => New_Copy_Tree (Item),
552 (Etype (Item), New_Occurrence_Of (Temp, Loc)));
554 Rewrite (Item, New_Occurrence_Of (Temp, Loc));
558 Make_Procedure_Call_Statement (Loc,
559 Name => New_Occurrence_Of (Pname, Loc),
560 Parameter_Associations => Exprs),
563 Rewrite (N, Make_Null_Statement (Loc));
568 -- For the class-wide dispatching cases, and for cases in which
569 -- the base type of the second argument matches the base type of
570 -- the corresponding formal parameter (that is to say the stream
571 -- operation is not inherited), we are all set, and can use the
572 -- argument unchanged.
574 -- For all other cases we do an unchecked conversion of the second
575 -- parameter to the type of the formal of the procedure we are
576 -- calling. This deals with the private type cases, and with going
577 -- to the root type as required in elementary type case.
579 if not Is_Class_Wide_Type (Entity (Pref))
580 and then not Is_Class_Wide_Type (Etype (Item))
581 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
584 Unchecked_Convert_To (Formal_Typ, Relocate_Node (Item)));
586 -- For untagged derived types set Assignment_OK, to prevent
587 -- copies from being created when the unchecked conversion
588 -- is expanded (which would happen in Remove_Side_Effects
589 -- if Expand_N_Unchecked_Conversion were allowed to call
590 -- Force_Evaluation). The copy could violate Ada semantics
591 -- in cases such as an actual that is an out parameter.
592 -- Note that this approach is also used in exp_ch7 for calls
593 -- to controlled type operations to prevent problems with
594 -- actuals wrapped in unchecked conversions.
596 if Is_Untagged_Derivation (Etype (Expression (Item))) then
597 Set_Assignment_OK (Item);
601 -- The stream operation to call maybe a renaming created by
602 -- an attribute definition clause, and may not be frozen yet.
603 -- Ensure that it has the necessary extra formals.
605 if not Is_Frozen (Pname) then
606 Create_Extra_Formals (Pname);
609 -- And now rewrite the call
612 Make_Procedure_Call_Statement (Loc,
613 Name => New_Occurrence_Of (Pname, Loc),
614 Parameter_Associations => Exprs));
617 end Rewrite_Stream_Proc_Call;
619 -- Start of processing for Expand_N_Attribute_Reference
622 -- Do required validity checking, if enabled. Do not apply check to
623 -- output parameters of an Asm instruction, since the value of this
624 -- is not set till after the attribute has been elaborated, and do
625 -- not apply the check to the arguments of a 'Read or 'Input attribute
626 -- reference since the scalar argument is an OUT scalar.
628 if Validity_Checks_On and then Validity_Check_Operands
629 and then Id /= Attribute_Asm_Output
630 and then Id /= Attribute_Read
631 and then Id /= Attribute_Input
636 Expr := First (Expressions (N));
637 while Present (Expr) loop
644 -- Ada 2005 (AI-318-02): If attribute prefix is a call to a build-in-
645 -- place function, then a temporary return object needs to be created
646 -- and access to it must be passed to the function. Currently we limit
647 -- such functions to those with inherently limited result subtypes, but
648 -- eventually we plan to expand the functions that are treated as
649 -- build-in-place to include other composite result types.
651 if Ada_Version >= Ada_05
652 and then Is_Build_In_Place_Function_Call (Pref)
654 Make_Build_In_Place_Call_In_Anonymous_Context (Pref);
657 -- If prefix is a protected type name, this is a reference to the
658 -- current instance of the type. For a component definition, nothing
659 -- to do (expansion will occur in the init proc). In other contexts,
660 -- rewrite into reference to current instance.
662 if Is_Protected_Self_Reference (Pref)
664 (Nkind_In (Parent (N), N_Index_Or_Discriminant_Constraint,
665 N_Discriminant_Association)
666 and then Nkind (Parent (Parent (Parent (Parent (N))))) =
667 N_Component_Definition)
669 Rewrite (Pref, Concurrent_Ref (Pref));
673 -- Remaining processing depends on specific attribute
681 when Attribute_Access |
682 Attribute_Unchecked_Access |
683 Attribute_Unrestricted_Access =>
685 Access_Cases : declare
686 Ref_Object : constant Node_Id := Get_Referenced_Object (Pref);
687 Btyp_DDT : Entity_Id;
689 function Enclosing_Object (N : Node_Id) return Node_Id;
690 -- If N denotes a compound name (selected component, indexed
691 -- component, or slice), returns the name of the outermost such
692 -- enclosing object. Otherwise returns N. If the object is a
693 -- renaming, then the renamed object is returned.
695 ----------------------
696 -- Enclosing_Object --
697 ----------------------
699 function Enclosing_Object (N : Node_Id) return Node_Id is
704 while Nkind_In (Obj_Name, N_Selected_Component,
708 Obj_Name := Prefix (Obj_Name);
711 return Get_Referenced_Object (Obj_Name);
712 end Enclosing_Object;
714 -- Local declarations
716 Enc_Object : constant Node_Id := Enclosing_Object (Ref_Object);
718 -- Start of processing for Access_Cases
721 Btyp_DDT := Designated_Type (Btyp);
723 -- Handle designated types that come from the limited view
725 if Ekind (Btyp_DDT) = E_Incomplete_Type
726 and then From_With_Type (Btyp_DDT)
727 and then Present (Non_Limited_View (Btyp_DDT))
729 Btyp_DDT := Non_Limited_View (Btyp_DDT);
731 elsif Is_Class_Wide_Type (Btyp_DDT)
732 and then Ekind (Etype (Btyp_DDT)) = E_Incomplete_Type
733 and then From_With_Type (Etype (Btyp_DDT))
734 and then Present (Non_Limited_View (Etype (Btyp_DDT)))
735 and then Present (Class_Wide_Type
736 (Non_Limited_View (Etype (Btyp_DDT))))
739 Class_Wide_Type (Non_Limited_View (Etype (Btyp_DDT)));
742 -- In order to improve the text of error messages, the designated
743 -- type of access-to-subprogram itypes is set by the semantics as
744 -- the associated subprogram entity (see sem_attr). Now we replace
745 -- such node with the proper E_Subprogram_Type itype.
747 if Id = Attribute_Unrestricted_Access
748 and then Is_Subprogram (Directly_Designated_Type (Typ))
750 -- The following conditions ensure that this special management
751 -- is done only for "Address!(Prim'Unrestricted_Access)" nodes.
752 -- At this stage other cases in which the designated type is
753 -- still a subprogram (instead of an E_Subprogram_Type) are
754 -- wrong because the semantics must have overridden the type of
755 -- the node with the type imposed by the context.
757 if Nkind (Parent (N)) = N_Unchecked_Type_Conversion
758 and then Etype (Parent (N)) = RTE (RE_Prim_Ptr)
760 Set_Etype (N, RTE (RE_Prim_Ptr));
764 Subp : constant Entity_Id :=
765 Directly_Designated_Type (Typ);
767 Extra : Entity_Id := Empty;
768 New_Formal : Entity_Id;
769 Old_Formal : Entity_Id := First_Formal (Subp);
770 Subp_Typ : Entity_Id;
773 Subp_Typ := Create_Itype (E_Subprogram_Type, N);
774 Set_Etype (Subp_Typ, Etype (Subp));
775 Set_Returns_By_Ref (Subp_Typ, Returns_By_Ref (Subp));
777 if Present (Old_Formal) then
778 New_Formal := New_Copy (Old_Formal);
779 Set_First_Entity (Subp_Typ, New_Formal);
782 Set_Scope (New_Formal, Subp_Typ);
783 Etyp := Etype (New_Formal);
785 -- Handle itypes. There is no need to duplicate
786 -- here the itypes associated with record types
787 -- (i.e the implicit full view of private types).
790 and then Ekind (Base_Type (Etyp)) /= E_Record_Type
792 Extra := New_Copy (Etyp);
793 Set_Parent (Extra, New_Formal);
794 Set_Etype (New_Formal, Extra);
795 Set_Scope (Extra, Subp_Typ);
799 Next_Formal (Old_Formal);
800 exit when No (Old_Formal);
802 Set_Next_Entity (New_Formal,
803 New_Copy (Old_Formal));
804 Next_Entity (New_Formal);
807 Set_Next_Entity (New_Formal, Empty);
808 Set_Last_Entity (Subp_Typ, Extra);
811 -- Now that the explicit formals have been duplicated,
812 -- any extra formals needed by the subprogram must be
815 if Present (Extra) then
816 Set_Extra_Formal (Extra, Empty);
819 Create_Extra_Formals (Subp_Typ);
820 Set_Directly_Designated_Type (Typ, Subp_Typ);
825 if Is_Access_Protected_Subprogram_Type (Btyp) then
826 Expand_Access_To_Protected_Op (N, Pref, Typ);
828 -- If prefix is a type name, this is a reference to the current
829 -- instance of the type, within its initialization procedure.
831 elsif Is_Entity_Name (Pref)
832 and then Is_Type (Entity (Pref))
839 -- If the current instance name denotes a task type, then
840 -- the access attribute is rewritten to be the name of the
841 -- "_task" parameter associated with the task type's task
842 -- procedure. An unchecked conversion is applied to ensure
843 -- a type match in cases of expander-generated calls (e.g.
846 if Is_Task_Type (Entity (Pref)) then
848 First_Entity (Get_Task_Body_Procedure (Entity (Pref)));
849 while Present (Formal) loop
850 exit when Chars (Formal) = Name_uTask;
851 Next_Entity (Formal);
854 pragma Assert (Present (Formal));
857 Unchecked_Convert_To (Typ,
858 New_Occurrence_Of (Formal, Loc)));
861 -- The expression must appear in a default expression,
862 -- (which in the initialization procedure is the
863 -- right-hand side of an assignment), and not in a
864 -- discriminant constraint.
868 while Present (Par) loop
869 exit when Nkind (Par) = N_Assignment_Statement;
871 if Nkind (Par) = N_Component_Declaration then
878 if Present (Par) then
880 Make_Attribute_Reference (Loc,
881 Prefix => Make_Identifier (Loc, Name_uInit),
882 Attribute_Name => Attribute_Name (N)));
884 Analyze_And_Resolve (N, Typ);
889 -- If the prefix of an Access attribute is a dereference of an
890 -- access parameter (or a renaming of such a dereference, or a
891 -- subcomponent of such a dereference) and the context is a
892 -- general access type (including the type of an object or
893 -- component with an access_definition, but not the anonymous
894 -- type of an access parameter or access discriminant), then
895 -- apply an accessibility check to the access parameter. We used
896 -- to rewrite the access parameter as a type conversion, but that
897 -- could only be done if the immediate prefix of the Access
898 -- attribute was the dereference, and didn't handle cases where
899 -- the attribute is applied to a subcomponent of the dereference,
900 -- since there's generally no available, appropriate access type
901 -- to convert to in that case. The attribute is passed as the
902 -- point to insert the check, because the access parameter may
903 -- come from a renaming, possibly in a different scope, and the
904 -- check must be associated with the attribute itself.
906 elsif Id = Attribute_Access
907 and then Nkind (Enc_Object) = N_Explicit_Dereference
908 and then Is_Entity_Name (Prefix (Enc_Object))
909 and then (Ekind (Btyp) = E_General_Access_Type
910 or else Is_Local_Anonymous_Access (Btyp))
911 and then Ekind (Entity (Prefix (Enc_Object))) in Formal_Kind
912 and then Ekind (Etype (Entity (Prefix (Enc_Object))))
913 = E_Anonymous_Access_Type
914 and then Present (Extra_Accessibility
915 (Entity (Prefix (Enc_Object))))
917 Apply_Accessibility_Check (Prefix (Enc_Object), Typ, N);
919 -- Ada 2005 (AI-251): If the designated type is an interface we
920 -- add an implicit conversion to force the displacement of the
921 -- pointer to reference the secondary dispatch table.
923 elsif Is_Interface (Btyp_DDT)
924 and then (Comes_From_Source (N)
925 or else Comes_From_Source (Ref_Object)
926 or else (Nkind (Ref_Object) in N_Has_Chars
927 and then Chars (Ref_Object) = Name_uInit))
929 if Nkind (Ref_Object) /= N_Explicit_Dereference then
931 -- No implicit conversion required if types match, or if
932 -- the prefix is the class_wide_type of the interface. In
933 -- either case passing an object of the interface type has
934 -- already set the pointer correctly.
936 if Btyp_DDT = Etype (Ref_Object)
937 or else (Is_Class_Wide_Type (Etype (Ref_Object))
939 Class_Wide_Type (Btyp_DDT) = Etype (Ref_Object))
945 Convert_To (Btyp_DDT,
946 New_Copy_Tree (Prefix (N))));
948 Analyze_And_Resolve (Prefix (N), Btyp_DDT);
951 -- When the object is an explicit dereference, convert the
952 -- dereference's prefix.
956 Obj_DDT : constant Entity_Id :=
958 (Directly_Designated_Type
959 (Etype (Prefix (Ref_Object))));
961 -- No implicit conversion required if designated types
964 if Obj_DDT /= Btyp_DDT
965 and then not (Is_Class_Wide_Type (Obj_DDT)
966 and then Etype (Obj_DDT) = Btyp_DDT)
970 New_Copy_Tree (Prefix (Ref_Object))));
971 Analyze_And_Resolve (N, Typ);
982 -- Transforms 'Adjacent into a call to the floating-point attribute
983 -- function Adjacent in Fat_xxx (where xxx is the root type)
985 when Attribute_Adjacent =>
986 Expand_Fpt_Attribute_RR (N);
992 when Attribute_Address => Address : declare
993 Task_Proc : Entity_Id;
996 -- If the prefix is a task or a task type, the useful address is that
997 -- of the procedure for the task body, i.e. the actual program unit.
998 -- We replace the original entity with that of the procedure.
1000 if Is_Entity_Name (Pref)
1001 and then Is_Task_Type (Entity (Pref))
1003 Task_Proc := Next_Entity (Root_Type (Ptyp));
1005 while Present (Task_Proc) loop
1006 exit when Ekind (Task_Proc) = E_Procedure
1007 and then Etype (First_Formal (Task_Proc)) =
1008 Corresponding_Record_Type (Ptyp);
1009 Next_Entity (Task_Proc);
1012 if Present (Task_Proc) then
1013 Set_Entity (Pref, Task_Proc);
1014 Set_Etype (Pref, Etype (Task_Proc));
1017 -- Similarly, the address of a protected operation is the address
1018 -- of the corresponding protected body, regardless of the protected
1019 -- object from which it is selected.
1021 elsif Nkind (Pref) = N_Selected_Component
1022 and then Is_Subprogram (Entity (Selector_Name (Pref)))
1023 and then Is_Protected_Type (Scope (Entity (Selector_Name (Pref))))
1027 External_Subprogram (Entity (Selector_Name (Pref))), Loc));
1029 elsif Nkind (Pref) = N_Explicit_Dereference
1030 and then Ekind (Ptyp) = E_Subprogram_Type
1031 and then Convention (Ptyp) = Convention_Protected
1033 -- The prefix is be a dereference of an access_to_protected_
1034 -- subprogram. The desired address is the second component of
1035 -- the record that represents the access.
1038 Addr : constant Entity_Id := Etype (N);
1039 Ptr : constant Node_Id := Prefix (Pref);
1040 T : constant Entity_Id :=
1041 Equivalent_Type (Base_Type (Etype (Ptr)));
1045 Unchecked_Convert_To (Addr,
1046 Make_Selected_Component (Loc,
1047 Prefix => Unchecked_Convert_To (T, Ptr),
1048 Selector_Name => New_Occurrence_Of (
1049 Next_Entity (First_Entity (T)), Loc))));
1051 Analyze_And_Resolve (N, Addr);
1054 -- Ada 2005 (AI-251): Class-wide interface objects are always
1055 -- "displaced" to reference the tag associated with the interface
1056 -- type. In order to obtain the real address of such objects we
1057 -- generate a call to a run-time subprogram that returns the base
1058 -- address of the object.
1060 -- This processing is not needed in the VM case, where dispatching
1061 -- issues are taken care of by the virtual machine.
1063 elsif Is_Class_Wide_Type (Ptyp)
1064 and then Is_Interface (Ptyp)
1065 and then Tagged_Type_Expansion
1066 and then not (Nkind (Pref) in N_Has_Entity
1067 and then Is_Subprogram (Entity (Pref)))
1070 Make_Function_Call (Loc,
1071 Name => New_Reference_To (RTE (RE_Base_Address), Loc),
1072 Parameter_Associations => New_List (
1073 Relocate_Node (N))));
1078 -- Deal with packed array reference, other cases are handled by
1081 if Involves_Packed_Array_Reference (Pref) then
1082 Expand_Packed_Address_Reference (N);
1090 when Attribute_Alignment => Alignment : declare
1094 -- For class-wide types, X'Class'Alignment is transformed into a
1095 -- direct reference to the Alignment of the class type, so that the
1096 -- back end does not have to deal with the X'Class'Alignment
1099 if Is_Entity_Name (Pref)
1100 and then Is_Class_Wide_Type (Entity (Pref))
1102 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
1105 -- For x'Alignment applied to an object of a class wide type,
1106 -- transform X'Alignment into a call to the predefined primitive
1107 -- operation _Alignment applied to X.
1109 elsif Is_Class_Wide_Type (Ptyp) then
1111 -- No need to do anything else compiling under restriction
1112 -- No_Dispatching_Calls. During the semantic analysis we
1113 -- already notified such violation.
1115 if Restriction_Active (No_Dispatching_Calls) then
1120 Make_Function_Call (Loc,
1121 Name => New_Reference_To
1122 (Find_Prim_Op (Ptyp, Name_uAlignment), Loc),
1123 Parameter_Associations => New_List (Pref));
1125 if Typ /= Standard_Integer then
1127 -- The context is a specific integer type with which the
1128 -- original attribute was compatible. The function has a
1129 -- specific type as well, so to preserve the compatibility
1130 -- we must convert explicitly.
1132 New_Node := Convert_To (Typ, New_Node);
1135 Rewrite (N, New_Node);
1136 Analyze_And_Resolve (N, Typ);
1139 -- For all other cases, we just have to deal with the case of
1140 -- the fact that the result can be universal.
1143 Apply_Universal_Integer_Attribute_Checks (N);
1151 when Attribute_AST_Entry => AST_Entry : declare
1156 Entry_Ref : Node_Id;
1157 -- The reference to the entry or entry family
1160 -- The index expression for an entry family reference, or
1161 -- the Empty if Entry_Ref references a simple entry.
1164 if Nkind (Pref) = N_Indexed_Component then
1165 Entry_Ref := Prefix (Pref);
1166 Index := First (Expressions (Pref));
1172 -- Get expression for Task_Id and the entry entity
1174 if Nkind (Entry_Ref) = N_Selected_Component then
1176 Make_Attribute_Reference (Loc,
1177 Attribute_Name => Name_Identity,
1178 Prefix => Prefix (Entry_Ref));
1180 Ttyp := Etype (Prefix (Entry_Ref));
1181 Eent := Entity (Selector_Name (Entry_Ref));
1185 Make_Function_Call (Loc,
1186 Name => New_Occurrence_Of (RTE (RE_Current_Task), Loc));
1188 Eent := Entity (Entry_Ref);
1190 -- We have to find the enclosing task to get the task type
1191 -- There must be one, since we already validated this earlier
1193 Ttyp := Current_Scope;
1194 while not Is_Task_Type (Ttyp) loop
1195 Ttyp := Scope (Ttyp);
1199 -- Now rewrite the attribute with a call to Create_AST_Handler
1202 Make_Function_Call (Loc,
1203 Name => New_Occurrence_Of (RTE (RE_Create_AST_Handler), Loc),
1204 Parameter_Associations => New_List (
1206 Entry_Index_Expression (Loc, Eent, Index, Ttyp))));
1208 Analyze_And_Resolve (N, RTE (RE_AST_Handler));
1215 -- We compute this if a component clause was present, otherwise we leave
1216 -- the computation up to the back end, since we don't know what layout
1219 -- Note that the attribute can apply to a naked record component
1220 -- in generated code (i.e. the prefix is an identifier that
1221 -- references the component or discriminant entity).
1223 when Attribute_Bit_Position => Bit_Position :
1228 if Nkind (Pref) = N_Identifier then
1229 CE := Entity (Pref);
1231 CE := Entity (Selector_Name (Pref));
1234 if Known_Static_Component_Bit_Offset (CE) then
1236 Make_Integer_Literal (Loc,
1237 Intval => Component_Bit_Offset (CE)));
1238 Analyze_And_Resolve (N, Typ);
1241 Apply_Universal_Integer_Attribute_Checks (N);
1249 -- A reference to P'Body_Version or P'Version is expanded to
1252 -- pragma Import (C, Vnn, "uuuuT");
1254 -- Get_Version_String (Vnn)
1256 -- where uuuu is the unit name (dots replaced by double underscore)
1257 -- and T is B for the cases of Body_Version, or Version applied to a
1258 -- subprogram acting as its own spec, and S for Version applied to a
1259 -- subprogram spec or package. This sequence of code references the
1260 -- the unsigned constant created in the main program by the binder.
1262 -- A special exception occurs for Standard, where the string
1263 -- returned is a copy of the library string in gnatvsn.ads.
1265 when Attribute_Body_Version | Attribute_Version => Version : declare
1266 E : constant Entity_Id :=
1267 Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
1272 -- If not library unit, get to containing library unit
1274 Pent := Entity (Pref);
1275 while Pent /= Standard_Standard
1276 and then Scope (Pent) /= Standard_Standard
1277 and then not Is_Child_Unit (Pent)
1279 Pent := Scope (Pent);
1282 -- Special case Standard and Standard.ASCII
1284 if Pent = Standard_Standard or else Pent = Standard_ASCII then
1286 Make_String_Literal (Loc,
1287 Strval => Verbose_Library_Version));
1292 -- Build required string constant
1294 Get_Name_String (Get_Unit_Name (Pent));
1297 for J in 1 .. Name_Len - 2 loop
1298 if Name_Buffer (J) = '.' then
1299 Store_String_Chars ("__");
1301 Store_String_Char (Get_Char_Code (Name_Buffer (J)));
1305 -- Case of subprogram acting as its own spec, always use body
1307 if Nkind (Declaration_Node (Pent)) in N_Subprogram_Specification
1308 and then Nkind (Parent (Declaration_Node (Pent))) =
1310 and then Acts_As_Spec (Parent (Declaration_Node (Pent)))
1312 Store_String_Chars ("B");
1314 -- Case of no body present, always use spec
1316 elsif not Unit_Requires_Body (Pent) then
1317 Store_String_Chars ("S");
1319 -- Otherwise use B for Body_Version, S for spec
1321 elsif Id = Attribute_Body_Version then
1322 Store_String_Chars ("B");
1324 Store_String_Chars ("S");
1328 Lib.Version_Referenced (S);
1330 -- Insert the object declaration
1332 Insert_Actions (N, New_List (
1333 Make_Object_Declaration (Loc,
1334 Defining_Identifier => E,
1335 Object_Definition =>
1336 New_Occurrence_Of (RTE (RE_Unsigned), Loc))));
1338 -- Set entity as imported with correct external name
1340 Set_Is_Imported (E);
1341 Set_Interface_Name (E, Make_String_Literal (Loc, S));
1343 -- Set entity as internal to ensure proper Sprint output of its
1344 -- implicit importation.
1346 Set_Is_Internal (E);
1348 -- And now rewrite original reference
1351 Make_Function_Call (Loc,
1352 Name => New_Reference_To (RTE (RE_Get_Version_String), Loc),
1353 Parameter_Associations => New_List (
1354 New_Occurrence_Of (E, Loc))));
1357 Analyze_And_Resolve (N, RTE (RE_Version_String));
1364 -- Transforms 'Ceiling into a call to the floating-point attribute
1365 -- function Ceiling in Fat_xxx (where xxx is the root type)
1367 when Attribute_Ceiling =>
1368 Expand_Fpt_Attribute_R (N);
1374 -- Transforms 'Callable attribute into a call to the Callable function
1376 when Attribute_Callable => Callable :
1378 -- We have an object of a task interface class-wide type as a prefix
1379 -- to Callable. Generate:
1380 -- callable (Task_Id (Pref._disp_get_task_id));
1382 if Ada_Version >= Ada_05
1383 and then Ekind (Ptyp) = E_Class_Wide_Type
1384 and then Is_Interface (Ptyp)
1385 and then Is_Task_Interface (Ptyp)
1388 Make_Function_Call (Loc,
1390 New_Reference_To (RTE (RE_Callable), Loc),
1391 Parameter_Associations => New_List (
1392 Make_Unchecked_Type_Conversion (Loc,
1394 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
1396 Make_Selected_Component (Loc,
1398 New_Copy_Tree (Pref),
1400 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
1404 Build_Call_With_Task (Pref, RTE (RE_Callable)));
1407 Analyze_And_Resolve (N, Standard_Boolean);
1414 -- Transforms 'Caller attribute into a call to either the
1415 -- Task_Entry_Caller or the Protected_Entry_Caller function.
1417 when Attribute_Caller => Caller : declare
1418 Id_Kind : constant Entity_Id := RTE (RO_AT_Task_Id);
1419 Ent : constant Entity_Id := Entity (Pref);
1420 Conctype : constant Entity_Id := Scope (Ent);
1421 Nest_Depth : Integer := 0;
1428 if Is_Protected_Type (Conctype) then
1429 case Corresponding_Runtime_Package (Conctype) is
1430 when System_Tasking_Protected_Objects_Entries =>
1433 (RTE (RE_Protected_Entry_Caller), Loc);
1435 when System_Tasking_Protected_Objects_Single_Entry =>
1438 (RTE (RE_Protected_Single_Entry_Caller), Loc);
1441 raise Program_Error;
1445 Unchecked_Convert_To (Id_Kind,
1446 Make_Function_Call (Loc,
1448 Parameter_Associations => New_List (
1450 (Find_Protection_Object (Current_Scope), Loc)))));
1455 -- Determine the nesting depth of the E'Caller attribute, that
1456 -- is, how many accept statements are nested within the accept
1457 -- statement for E at the point of E'Caller. The runtime uses
1458 -- this depth to find the specified entry call.
1460 for J in reverse 0 .. Scope_Stack.Last loop
1461 S := Scope_Stack.Table (J).Entity;
1463 -- We should not reach the scope of the entry, as it should
1464 -- already have been checked in Sem_Attr that this attribute
1465 -- reference is within a matching accept statement.
1467 pragma Assert (S /= Conctype);
1472 elsif Is_Entry (S) then
1473 Nest_Depth := Nest_Depth + 1;
1478 Unchecked_Convert_To (Id_Kind,
1479 Make_Function_Call (Loc,
1481 New_Reference_To (RTE (RE_Task_Entry_Caller), Loc),
1482 Parameter_Associations => New_List (
1483 Make_Integer_Literal (Loc,
1484 Intval => Int (Nest_Depth))))));
1487 Analyze_And_Resolve (N, Id_Kind);
1494 -- Transforms 'Compose into a call to the floating-point attribute
1495 -- function Compose in Fat_xxx (where xxx is the root type)
1497 -- Note: we strictly should have special code here to deal with the
1498 -- case of absurdly negative arguments (less than Integer'First)
1499 -- which will return a (signed) zero value, but it hardly seems
1500 -- worth the effort. Absurdly large positive arguments will raise
1501 -- constraint error which is fine.
1503 when Attribute_Compose =>
1504 Expand_Fpt_Attribute_RI (N);
1510 when Attribute_Constrained => Constrained : declare
1511 Formal_Ent : constant Entity_Id := Param_Entity (Pref);
1513 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean;
1514 -- Ada 2005 (AI-363): Returns True if the object name Obj denotes a
1515 -- view of an aliased object whose subtype is constrained.
1517 ---------------------------------
1518 -- Is_Constrained_Aliased_View --
1519 ---------------------------------
1521 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean is
1525 if Is_Entity_Name (Obj) then
1528 if Present (Renamed_Object (E)) then
1529 return Is_Constrained_Aliased_View (Renamed_Object (E));
1531 return Is_Aliased (E) and then Is_Constrained (Etype (E));
1535 return Is_Aliased_View (Obj)
1537 (Is_Constrained (Etype (Obj))
1538 or else (Nkind (Obj) = N_Explicit_Dereference
1540 not Has_Constrained_Partial_View
1541 (Base_Type (Etype (Obj)))));
1543 end Is_Constrained_Aliased_View;
1545 -- Start of processing for Constrained
1548 -- Reference to a parameter where the value is passed as an extra
1549 -- actual, corresponding to the extra formal referenced by the
1550 -- Extra_Constrained field of the corresponding formal. If this
1551 -- is an entry in-parameter, it is replaced by a constant renaming
1552 -- for which Extra_Constrained is never created.
1554 if Present (Formal_Ent)
1555 and then Ekind (Formal_Ent) /= E_Constant
1556 and then Present (Extra_Constrained (Formal_Ent))
1560 (Extra_Constrained (Formal_Ent), Sloc (N)));
1562 -- For variables with a Extra_Constrained field, we use the
1563 -- corresponding entity.
1565 elsif Nkind (Pref) = N_Identifier
1566 and then Ekind (Entity (Pref)) = E_Variable
1567 and then Present (Extra_Constrained (Entity (Pref)))
1571 (Extra_Constrained (Entity (Pref)), Sloc (N)));
1573 -- For all other entity names, we can tell at compile time
1575 elsif Is_Entity_Name (Pref) then
1577 Ent : constant Entity_Id := Entity (Pref);
1581 -- (RM J.4) obsolescent cases
1583 if Is_Type (Ent) then
1587 if Is_Private_Type (Ent) then
1588 Res := not Has_Discriminants (Ent)
1589 or else Is_Constrained (Ent);
1591 -- It not a private type, must be a generic actual type
1592 -- that corresponded to a private type. We know that this
1593 -- correspondence holds, since otherwise the reference
1594 -- within the generic template would have been illegal.
1597 if Is_Composite_Type (Underlying_Type (Ent)) then
1598 Res := Is_Constrained (Ent);
1604 -- If the prefix is not a variable or is aliased, then
1605 -- definitely true; if it's a formal parameter without an
1606 -- associated extra formal, then treat it as constrained.
1608 -- Ada 2005 (AI-363): An aliased prefix must be known to be
1609 -- constrained in order to set the attribute to True.
1611 elsif not Is_Variable (Pref)
1612 or else Present (Formal_Ent)
1613 or else (Ada_Version < Ada_05
1614 and then Is_Aliased_View (Pref))
1615 or else (Ada_Version >= Ada_05
1616 and then Is_Constrained_Aliased_View (Pref))
1620 -- Variable case, look at type to see if it is constrained.
1621 -- Note that the one case where this is not accurate (the
1622 -- procedure formal case), has been handled above.
1624 -- We use the Underlying_Type here (and below) in case the
1625 -- type is private without discriminants, but the full type
1626 -- has discriminants. This case is illegal, but we generate it
1627 -- internally for passing to the Extra_Constrained parameter.
1630 Res := Is_Constrained (Underlying_Type (Etype (Ent)));
1634 New_Reference_To (Boolean_Literals (Res), Loc));
1637 -- Prefix is not an entity name. These are also cases where we can
1638 -- always tell at compile time by looking at the form and type of the
1639 -- prefix. If an explicit dereference of an object with constrained
1640 -- partial view, this is unconstrained (Ada 2005 AI-363).
1646 not Is_Variable (Pref)
1648 (Nkind (Pref) = N_Explicit_Dereference
1650 not Has_Constrained_Partial_View (Base_Type (Ptyp)))
1651 or else Is_Constrained (Underlying_Type (Ptyp))),
1655 Analyze_And_Resolve (N, Standard_Boolean);
1662 -- Transforms 'Copy_Sign into a call to the floating-point attribute
1663 -- function Copy_Sign in Fat_xxx (where xxx is the root type)
1665 when Attribute_Copy_Sign =>
1666 Expand_Fpt_Attribute_RR (N);
1672 -- Transforms 'Count attribute into a call to the Count function
1674 when Attribute_Count => Count : declare
1676 Conctyp : Entity_Id;
1678 Entry_Id : Entity_Id;
1683 -- If the prefix is a member of an entry family, retrieve both
1684 -- entry name and index. For a simple entry there is no index.
1686 if Nkind (Pref) = N_Indexed_Component then
1687 Entnam := Prefix (Pref);
1688 Index := First (Expressions (Pref));
1694 Entry_Id := Entity (Entnam);
1696 -- Find the concurrent type in which this attribute is referenced
1697 -- (there had better be one).
1699 Conctyp := Current_Scope;
1700 while not Is_Concurrent_Type (Conctyp) loop
1701 Conctyp := Scope (Conctyp);
1706 if Is_Protected_Type (Conctyp) then
1707 case Corresponding_Runtime_Package (Conctyp) is
1708 when System_Tasking_Protected_Objects_Entries =>
1709 Name := New_Reference_To (RTE (RE_Protected_Count), Loc);
1712 Make_Function_Call (Loc,
1714 Parameter_Associations => New_List (
1716 (Find_Protection_Object (Current_Scope), Loc),
1717 Entry_Index_Expression
1718 (Loc, Entry_Id, Index, Scope (Entry_Id))));
1720 when System_Tasking_Protected_Objects_Single_Entry =>
1722 New_Reference_To (RTE (RE_Protected_Count_Entry), Loc);
1725 Make_Function_Call (Loc,
1727 Parameter_Associations => New_List (
1729 (Find_Protection_Object (Current_Scope), Loc)));
1732 raise Program_Error;
1739 Make_Function_Call (Loc,
1740 Name => New_Reference_To (RTE (RE_Task_Count), Loc),
1741 Parameter_Associations => New_List (
1742 Entry_Index_Expression (Loc,
1743 Entry_Id, Index, Scope (Entry_Id))));
1746 -- The call returns type Natural but the context is universal integer
1747 -- so any integer type is allowed. The attribute was already resolved
1748 -- so its Etype is the required result type. If the base type of the
1749 -- context type is other than Standard.Integer we put in a conversion
1750 -- to the required type. This can be a normal typed conversion since
1751 -- both input and output types of the conversion are integer types
1753 if Base_Type (Typ) /= Base_Type (Standard_Integer) then
1754 Rewrite (N, Convert_To (Typ, Call));
1759 Analyze_And_Resolve (N, Typ);
1766 -- This processing is shared by Elab_Spec
1768 -- What we do is to insert the following declarations
1771 -- pragma Import (C, enn, "name___elabb/s");
1773 -- and then the Elab_Body/Spec attribute is replaced by a reference
1774 -- to this defining identifier.
1776 when Attribute_Elab_Body |
1777 Attribute_Elab_Spec =>
1780 Ent : constant Entity_Id :=
1781 Make_Defining_Identifier (Loc,
1782 New_Internal_Name ('E'));
1786 procedure Make_Elab_String (Nod : Node_Id);
1787 -- Given Nod, an identifier, or a selected component, put the
1788 -- image into the current string literal, with double underline
1789 -- between components.
1791 ----------------------
1792 -- Make_Elab_String --
1793 ----------------------
1795 procedure Make_Elab_String (Nod : Node_Id) is
1797 if Nkind (Nod) = N_Selected_Component then
1798 Make_Elab_String (Prefix (Nod));
1802 Store_String_Char ('$');
1804 Store_String_Char ('.');
1806 Store_String_Char ('_');
1807 Store_String_Char ('_');
1810 Get_Name_String (Chars (Selector_Name (Nod)));
1813 pragma Assert (Nkind (Nod) = N_Identifier);
1814 Get_Name_String (Chars (Nod));
1817 Store_String_Chars (Name_Buffer (1 .. Name_Len));
1818 end Make_Elab_String;
1820 -- Start of processing for Elab_Body/Elab_Spec
1823 -- First we need to prepare the string literal for the name of
1824 -- the elaboration routine to be referenced.
1827 Make_Elab_String (Pref);
1829 if VM_Target = No_VM then
1830 Store_String_Chars ("___elab");
1831 Lang := Make_Identifier (Loc, Name_C);
1833 Store_String_Chars ("._elab");
1834 Lang := Make_Identifier (Loc, Name_Ada);
1837 if Id = Attribute_Elab_Body then
1838 Store_String_Char ('b');
1840 Store_String_Char ('s');
1845 Insert_Actions (N, New_List (
1846 Make_Subprogram_Declaration (Loc,
1848 Make_Procedure_Specification (Loc,
1849 Defining_Unit_Name => Ent)),
1852 Chars => Name_Import,
1853 Pragma_Argument_Associations => New_List (
1854 Make_Pragma_Argument_Association (Loc,
1855 Expression => Lang),
1857 Make_Pragma_Argument_Association (Loc,
1859 Make_Identifier (Loc, Chars (Ent))),
1861 Make_Pragma_Argument_Association (Loc,
1863 Make_String_Literal (Loc, Str))))));
1865 Set_Entity (N, Ent);
1866 Rewrite (N, New_Occurrence_Of (Ent, Loc));
1873 -- Elaborated is always True for preelaborated units, predefined units,
1874 -- pure units and units which have Elaborate_Body pragmas. These units
1875 -- have no elaboration entity.
1877 -- Note: The Elaborated attribute is never passed to the back end
1879 when Attribute_Elaborated => Elaborated : declare
1880 Ent : constant Entity_Id := Entity (Pref);
1883 if Present (Elaboration_Entity (Ent)) then
1885 New_Occurrence_Of (Elaboration_Entity (Ent), Loc));
1887 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
1895 when Attribute_Enum_Rep => Enum_Rep :
1897 -- X'Enum_Rep (Y) expands to
1901 -- This is simply a direct conversion from the enumeration type to
1902 -- the target integer type, which is treated by the back end as a
1903 -- normal integer conversion, treating the enumeration type as an
1904 -- integer, which is exactly what we want! We set Conversion_OK to
1905 -- make sure that the analyzer does not complain about what otherwise
1906 -- might be an illegal conversion.
1908 if Is_Non_Empty_List (Exprs) then
1910 OK_Convert_To (Typ, Relocate_Node (First (Exprs))));
1912 -- X'Enum_Rep where X is an enumeration literal is replaced by
1913 -- the literal value.
1915 elsif Ekind (Entity (Pref)) = E_Enumeration_Literal then
1917 Make_Integer_Literal (Loc, Enumeration_Rep (Entity (Pref))));
1919 -- If this is a renaming of a literal, recover the representation
1922 elsif Ekind (Entity (Pref)) = E_Constant
1923 and then Present (Renamed_Object (Entity (Pref)))
1925 Ekind (Entity (Renamed_Object (Entity (Pref))))
1926 = E_Enumeration_Literal
1929 Make_Integer_Literal (Loc,
1930 Enumeration_Rep (Entity (Renamed_Object (Entity (Pref))))));
1932 -- X'Enum_Rep where X is an object does a direct unchecked conversion
1933 -- of the object value, as described for the type case above.
1937 OK_Convert_To (Typ, Relocate_Node (Pref)));
1941 Analyze_And_Resolve (N, Typ);
1948 when Attribute_Enum_Val => Enum_Val : declare
1950 Btyp : constant Entity_Id := Base_Type (Ptyp);
1953 -- X'Enum_Val (Y) expands to
1955 -- [constraint_error when _rep_to_pos (Y, False) = -1, msg]
1958 Expr := Unchecked_Convert_To (Ptyp, First (Exprs));
1961 Make_Raise_Constraint_Error (Loc,
1965 Make_Function_Call (Loc,
1967 New_Reference_To (TSS (Btyp, TSS_Rep_To_Pos), Loc),
1968 Parameter_Associations => New_List (
1969 Relocate_Node (Duplicate_Subexpr (Expr)),
1970 New_Occurrence_Of (Standard_False, Loc))),
1972 Right_Opnd => Make_Integer_Literal (Loc, -1)),
1973 Reason => CE_Range_Check_Failed));
1976 Analyze_And_Resolve (N, Ptyp);
1983 -- Transforms 'Exponent into a call to the floating-point attribute
1984 -- function Exponent in Fat_xxx (where xxx is the root type)
1986 when Attribute_Exponent =>
1987 Expand_Fpt_Attribute_R (N);
1993 -- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag)
1995 when Attribute_External_Tag => External_Tag :
1998 Make_Function_Call (Loc,
1999 Name => New_Reference_To (RTE (RE_External_Tag), Loc),
2000 Parameter_Associations => New_List (
2001 Make_Attribute_Reference (Loc,
2002 Attribute_Name => Name_Tag,
2003 Prefix => Prefix (N)))));
2005 Analyze_And_Resolve (N, Standard_String);
2012 when Attribute_First =>
2014 -- If the prefix type is a constrained packed array type which
2015 -- already has a Packed_Array_Type representation defined, then
2016 -- replace this attribute with a direct reference to 'First of the
2017 -- appropriate index subtype (since otherwise the back end will try
2018 -- to give us the value of 'First for this implementation type).
2020 if Is_Constrained_Packed_Array (Ptyp) then
2022 Make_Attribute_Reference (Loc,
2023 Attribute_Name => Name_First,
2024 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
2025 Analyze_And_Resolve (N, Typ);
2027 elsif Is_Access_Type (Ptyp) then
2028 Apply_Access_Check (N);
2035 -- Compute this if component clause was present, otherwise we leave the
2036 -- computation to be completed in the back-end, since we don't know what
2037 -- layout will be chosen.
2039 when Attribute_First_Bit => First_Bit : declare
2040 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2043 if Known_Static_Component_Bit_Offset (CE) then
2045 Make_Integer_Literal (Loc,
2046 Component_Bit_Offset (CE) mod System_Storage_Unit));
2048 Analyze_And_Resolve (N, Typ);
2051 Apply_Universal_Integer_Attribute_Checks (N);
2061 -- fixtype'Fixed_Value (integer-value)
2065 -- fixtype(integer-value)
2067 -- We do all the required analysis of the conversion here, because we do
2068 -- not want this to go through the fixed-point conversion circuits. Note
2069 -- that the back end always treats fixed-point as equivalent to the
2070 -- corresponding integer type anyway.
2072 when Attribute_Fixed_Value => Fixed_Value :
2075 Make_Type_Conversion (Loc,
2076 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2077 Expression => Relocate_Node (First (Exprs))));
2078 Set_Etype (N, Entity (Pref));
2081 -- Note: it might appear that a properly analyzed unchecked conversion
2082 -- would be just fine here, but that's not the case, since the full
2083 -- range checks performed by the following call are critical!
2085 Apply_Type_Conversion_Checks (N);
2092 -- Transforms 'Floor into a call to the floating-point attribute
2093 -- function Floor in Fat_xxx (where xxx is the root type)
2095 when Attribute_Floor =>
2096 Expand_Fpt_Attribute_R (N);
2102 -- For the fixed-point type Typ:
2108 -- Result_Type (System.Fore (Universal_Real (Type'First)),
2109 -- Universal_Real (Type'Last))
2111 -- Note that we know that the type is a non-static subtype, or Fore
2112 -- would have itself been computed dynamically in Eval_Attribute.
2114 when Attribute_Fore => Fore : begin
2117 Make_Function_Call (Loc,
2118 Name => New_Reference_To (RTE (RE_Fore), Loc),
2120 Parameter_Associations => New_List (
2121 Convert_To (Universal_Real,
2122 Make_Attribute_Reference (Loc,
2123 Prefix => New_Reference_To (Ptyp, Loc),
2124 Attribute_Name => Name_First)),
2126 Convert_To (Universal_Real,
2127 Make_Attribute_Reference (Loc,
2128 Prefix => New_Reference_To (Ptyp, Loc),
2129 Attribute_Name => Name_Last))))));
2131 Analyze_And_Resolve (N, Typ);
2138 -- Transforms 'Fraction into a call to the floating-point attribute
2139 -- function Fraction in Fat_xxx (where xxx is the root type)
2141 when Attribute_Fraction =>
2142 Expand_Fpt_Attribute_R (N);
2148 when Attribute_From_Any => From_Any : declare
2149 P_Type : constant Entity_Id := Etype (Pref);
2150 Decls : constant List_Id := New_List;
2153 Build_From_Any_Call (P_Type,
2154 Relocate_Node (First (Exprs)),
2156 Insert_Actions (N, Decls);
2157 Analyze_And_Resolve (N, P_Type);
2164 -- For an exception returns a reference to the exception data:
2165 -- Exception_Id!(Prefix'Reference)
2167 -- For a task it returns a reference to the _task_id component of
2168 -- corresponding record:
2170 -- taskV!(Prefix)._Task_Id, converted to the type Task_Id defined
2172 -- in Ada.Task_Identification
2174 when Attribute_Identity => Identity : declare
2175 Id_Kind : Entity_Id;
2178 if Ptyp = Standard_Exception_Type then
2179 Id_Kind := RTE (RE_Exception_Id);
2181 if Present (Renamed_Object (Entity (Pref))) then
2182 Set_Entity (Pref, Renamed_Object (Entity (Pref)));
2186 Unchecked_Convert_To (Id_Kind, Make_Reference (Loc, Pref)));
2188 Id_Kind := RTE (RO_AT_Task_Id);
2190 -- If the prefix is a task interface, the Task_Id is obtained
2191 -- dynamically through a dispatching call, as for other task
2192 -- attributes applied to interfaces.
2194 if Ada_Version >= Ada_05
2195 and then Ekind (Ptyp) = E_Class_Wide_Type
2196 and then Is_Interface (Ptyp)
2197 and then Is_Task_Interface (Ptyp)
2200 Unchecked_Convert_To (Id_Kind,
2201 Make_Selected_Component (Loc,
2203 New_Copy_Tree (Pref),
2205 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))));
2209 Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref)));
2213 Analyze_And_Resolve (N, Id_Kind);
2220 -- Image attribute is handled in separate unit Exp_Imgv
2222 when Attribute_Image =>
2223 Exp_Imgv.Expand_Image_Attribute (N);
2229 -- X'Img is expanded to typ'Image (X), where typ is the type of X
2231 when Attribute_Img => Img :
2234 Make_Attribute_Reference (Loc,
2235 Prefix => New_Reference_To (Ptyp, Loc),
2236 Attribute_Name => Name_Image,
2237 Expressions => New_List (Relocate_Node (Pref))));
2239 Analyze_And_Resolve (N, Standard_String);
2246 when Attribute_Input => Input : declare
2247 P_Type : constant Entity_Id := Entity (Pref);
2248 B_Type : constant Entity_Id := Base_Type (P_Type);
2249 U_Type : constant Entity_Id := Underlying_Type (P_Type);
2250 Strm : constant Node_Id := First (Exprs);
2258 Cntrl : Node_Id := Empty;
2259 -- Value for controlling argument in call. Always Empty except in
2260 -- the dispatching (class-wide type) case, where it is a reference
2261 -- to the dummy object initialized to the right internal tag.
2263 procedure Freeze_Stream_Subprogram (F : Entity_Id);
2264 -- The expansion of the attribute reference may generate a call to
2265 -- a user-defined stream subprogram that is frozen by the call. This
2266 -- can lead to access-before-elaboration problem if the reference
2267 -- appears in an object declaration and the subprogram body has not
2268 -- been seen. The freezing of the subprogram requires special code
2269 -- because it appears in an expanded context where expressions do
2270 -- not freeze their constituents.
2272 ------------------------------
2273 -- Freeze_Stream_Subprogram --
2274 ------------------------------
2276 procedure Freeze_Stream_Subprogram (F : Entity_Id) is
2277 Decl : constant Node_Id := Unit_Declaration_Node (F);
2281 -- If this is user-defined subprogram, the corresponding
2282 -- stream function appears as a renaming-as-body, and the
2283 -- user subprogram must be retrieved by tree traversal.
2286 and then Nkind (Decl) = N_Subprogram_Declaration
2287 and then Present (Corresponding_Body (Decl))
2289 Bod := Corresponding_Body (Decl);
2291 if Nkind (Unit_Declaration_Node (Bod)) =
2292 N_Subprogram_Renaming_Declaration
2294 Set_Is_Frozen (Entity (Name (Unit_Declaration_Node (Bod))));
2297 end Freeze_Stream_Subprogram;
2299 -- Start of processing for Input
2302 -- If no underlying type, we have an error that will be diagnosed
2303 -- elsewhere, so here we just completely ignore the expansion.
2309 -- If there is a TSS for Input, just call it
2311 Fname := Find_Stream_Subprogram (P_Type, TSS_Stream_Input);
2313 if Present (Fname) then
2317 -- If there is a Stream_Convert pragma, use it, we rewrite
2319 -- sourcetyp'Input (stream)
2323 -- sourcetyp (streamread (strmtyp'Input (stream)));
2325 -- where streamread is the given Read function that converts an
2326 -- argument of type strmtyp to type sourcetyp or a type from which
2327 -- it is derived (extra conversion required for the derived case).
2329 Prag := Get_Stream_Convert_Pragma (P_Type);
2331 if Present (Prag) then
2332 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
2333 Rfunc := Entity (Expression (Arg2));
2337 Make_Function_Call (Loc,
2338 Name => New_Occurrence_Of (Rfunc, Loc),
2339 Parameter_Associations => New_List (
2340 Make_Attribute_Reference (Loc,
2343 (Etype (First_Formal (Rfunc)), Loc),
2344 Attribute_Name => Name_Input,
2345 Expressions => Exprs)))));
2347 Analyze_And_Resolve (N, B_Type);
2352 elsif Is_Elementary_Type (U_Type) then
2354 -- A special case arises if we have a defined _Read routine,
2355 -- since in this case we are required to call this routine.
2357 if Present (TSS (Base_Type (U_Type), TSS_Stream_Read)) then
2358 Build_Record_Or_Elementary_Input_Function
2359 (Loc, U_Type, Decl, Fname);
2360 Insert_Action (N, Decl);
2362 -- For normal cases, we call the I_xxx routine directly
2365 Rewrite (N, Build_Elementary_Input_Call (N));
2366 Analyze_And_Resolve (N, P_Type);
2372 elsif Is_Array_Type (U_Type) then
2373 Build_Array_Input_Function (Loc, U_Type, Decl, Fname);
2374 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
2376 -- Dispatching case with class-wide type
2378 elsif Is_Class_Wide_Type (P_Type) then
2380 -- No need to do anything else compiling under restriction
2381 -- No_Dispatching_Calls. During the semantic analysis we
2382 -- already notified such violation.
2384 if Restriction_Active (No_Dispatching_Calls) then
2389 Rtyp : constant Entity_Id := Root_Type (P_Type);
2394 -- Read the internal tag (RM 13.13.2(34)) and use it to
2395 -- initialize a dummy tag object:
2397 -- Dnn : Ada.Tags.Tag
2398 -- := Descendant_Tag (String'Input (Strm), P_Type);
2400 -- This dummy object is used only to provide a controlling
2401 -- argument for the eventual _Input call. Descendant_Tag is
2402 -- called rather than Internal_Tag to ensure that we have a
2403 -- tag for a type that is descended from the prefix type and
2404 -- declared at the same accessibility level (the exception
2405 -- Tag_Error will be raised otherwise). The level check is
2406 -- required for Ada 2005 because tagged types can be
2407 -- extended in nested scopes (AI-344).
2410 Make_Defining_Identifier (Loc,
2411 Chars => New_Internal_Name ('D'));
2414 Make_Object_Declaration (Loc,
2415 Defining_Identifier => Dnn,
2416 Object_Definition =>
2417 New_Occurrence_Of (RTE (RE_Tag), Loc),
2419 Make_Function_Call (Loc,
2421 New_Occurrence_Of (RTE (RE_Descendant_Tag), Loc),
2422 Parameter_Associations => New_List (
2423 Make_Attribute_Reference (Loc,
2425 New_Occurrence_Of (Standard_String, Loc),
2426 Attribute_Name => Name_Input,
2427 Expressions => New_List (
2429 (Duplicate_Subexpr (Strm)))),
2430 Make_Attribute_Reference (Loc,
2431 Prefix => New_Reference_To (P_Type, Loc),
2432 Attribute_Name => Name_Tag))));
2434 Insert_Action (N, Decl);
2436 -- Now we need to get the entity for the call, and construct
2437 -- a function call node, where we preset a reference to Dnn
2438 -- as the controlling argument (doing an unchecked convert
2439 -- to the class-wide tagged type to make it look like a real
2442 Fname := Find_Prim_Op (Rtyp, TSS_Stream_Input);
2443 Cntrl := Unchecked_Convert_To (P_Type,
2444 New_Occurrence_Of (Dnn, Loc));
2445 Set_Etype (Cntrl, P_Type);
2446 Set_Parent (Cntrl, N);
2449 -- For tagged types, use the primitive Input function
2451 elsif Is_Tagged_Type (U_Type) then
2452 Fname := Find_Prim_Op (U_Type, TSS_Stream_Input);
2454 -- All other record type cases, including protected records. The
2455 -- latter only arise for expander generated code for handling
2456 -- shared passive partition access.
2460 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
2462 -- Ada 2005 (AI-216): Program_Error is raised executing default
2463 -- implementation of the Input attribute of an unchecked union
2464 -- type if the type lacks default discriminant values.
2466 if Is_Unchecked_Union (Base_Type (U_Type))
2467 and then No (Discriminant_Constraint (U_Type))
2470 Make_Raise_Program_Error (Loc,
2471 Reason => PE_Unchecked_Union_Restriction));
2476 Build_Record_Or_Elementary_Input_Function
2477 (Loc, Base_Type (U_Type), Decl, Fname);
2478 Insert_Action (N, Decl);
2480 if Nkind (Parent (N)) = N_Object_Declaration
2481 and then Is_Record_Type (U_Type)
2483 -- The stream function may contain calls to user-defined
2484 -- Read procedures for individual components.
2491 Comp := First_Component (U_Type);
2492 while Present (Comp) loop
2494 Find_Stream_Subprogram
2495 (Etype (Comp), TSS_Stream_Read);
2497 if Present (Func) then
2498 Freeze_Stream_Subprogram (Func);
2501 Next_Component (Comp);
2508 -- If we fall through, Fname is the function to be called. The result
2509 -- is obtained by calling the appropriate function, then converting
2510 -- the result. The conversion does a subtype check.
2513 Make_Function_Call (Loc,
2514 Name => New_Occurrence_Of (Fname, Loc),
2515 Parameter_Associations => New_List (
2516 Relocate_Node (Strm)));
2518 Set_Controlling_Argument (Call, Cntrl);
2519 Rewrite (N, Unchecked_Convert_To (P_Type, Call));
2520 Analyze_And_Resolve (N, P_Type);
2522 if Nkind (Parent (N)) = N_Object_Declaration then
2523 Freeze_Stream_Subprogram (Fname);
2533 -- inttype'Fixed_Value (fixed-value)
2537 -- inttype(integer-value))
2539 -- we do all the required analysis of the conversion here, because we do
2540 -- not want this to go through the fixed-point conversion circuits. Note
2541 -- that the back end always treats fixed-point as equivalent to the
2542 -- corresponding integer type anyway.
2544 when Attribute_Integer_Value => Integer_Value :
2547 Make_Type_Conversion (Loc,
2548 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2549 Expression => Relocate_Node (First (Exprs))));
2550 Set_Etype (N, Entity (Pref));
2553 -- Note: it might appear that a properly analyzed unchecked conversion
2554 -- would be just fine here, but that's not the case, since the full
2555 -- range checks performed by the following call are critical!
2557 Apply_Type_Conversion_Checks (N);
2564 when Attribute_Invalid_Value =>
2565 Rewrite (N, Get_Simple_Init_Val (Ptyp, N));
2571 when Attribute_Last =>
2573 -- If the prefix type is a constrained packed array type which
2574 -- already has a Packed_Array_Type representation defined, then
2575 -- replace this attribute with a direct reference to 'Last of the
2576 -- appropriate index subtype (since otherwise the back end will try
2577 -- to give us the value of 'Last for this implementation type).
2579 if Is_Constrained_Packed_Array (Ptyp) then
2581 Make_Attribute_Reference (Loc,
2582 Attribute_Name => Name_Last,
2583 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
2584 Analyze_And_Resolve (N, Typ);
2586 elsif Is_Access_Type (Ptyp) then
2587 Apply_Access_Check (N);
2594 -- We compute this if a component clause was present, otherwise we leave
2595 -- the computation up to the back end, since we don't know what layout
2598 when Attribute_Last_Bit => Last_Bit : declare
2599 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2602 if Known_Static_Component_Bit_Offset (CE)
2603 and then Known_Static_Esize (CE)
2606 Make_Integer_Literal (Loc,
2607 Intval => (Component_Bit_Offset (CE) mod System_Storage_Unit)
2610 Analyze_And_Resolve (N, Typ);
2613 Apply_Universal_Integer_Attribute_Checks (N);
2621 -- Transforms 'Leading_Part into a call to the floating-point attribute
2622 -- function Leading_Part in Fat_xxx (where xxx is the root type)
2624 -- Note: strictly, we should generate special case code to deal with
2625 -- absurdly large positive arguments (greater than Integer'Last), which
2626 -- result in returning the first argument unchanged, but it hardly seems
2627 -- worth the effort. We raise constraint error for absurdly negative
2628 -- arguments which is fine.
2630 when Attribute_Leading_Part =>
2631 Expand_Fpt_Attribute_RI (N);
2637 when Attribute_Length => declare
2642 -- Processing for packed array types
2644 if Is_Array_Type (Ptyp) and then Is_Packed (Ptyp) then
2645 Ityp := Get_Index_Subtype (N);
2647 -- If the index type, Ityp, is an enumeration type with holes,
2648 -- then we calculate X'Length explicitly using
2651 -- (0, Ityp'Pos (X'Last (N)) -
2652 -- Ityp'Pos (X'First (N)) + 1);
2654 -- Since the bounds in the template are the representation values
2655 -- and the back end would get the wrong value.
2657 if Is_Enumeration_Type (Ityp)
2658 and then Present (Enum_Pos_To_Rep (Base_Type (Ityp)))
2663 Xnum := Expr_Value (First (Expressions (N)));
2667 Make_Attribute_Reference (Loc,
2668 Prefix => New_Occurrence_Of (Typ, Loc),
2669 Attribute_Name => Name_Max,
2670 Expressions => New_List
2671 (Make_Integer_Literal (Loc, 0),
2675 Make_Op_Subtract (Loc,
2677 Make_Attribute_Reference (Loc,
2678 Prefix => New_Occurrence_Of (Ityp, Loc),
2679 Attribute_Name => Name_Pos,
2681 Expressions => New_List (
2682 Make_Attribute_Reference (Loc,
2683 Prefix => Duplicate_Subexpr (Pref),
2684 Attribute_Name => Name_Last,
2685 Expressions => New_List (
2686 Make_Integer_Literal (Loc, Xnum))))),
2689 Make_Attribute_Reference (Loc,
2690 Prefix => New_Occurrence_Of (Ityp, Loc),
2691 Attribute_Name => Name_Pos,
2693 Expressions => New_List (
2694 Make_Attribute_Reference (Loc,
2696 Duplicate_Subexpr_No_Checks (Pref),
2697 Attribute_Name => Name_First,
2698 Expressions => New_List (
2699 Make_Integer_Literal (Loc, Xnum)))))),
2701 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
2703 Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
2706 -- If the prefix type is a constrained packed array type which
2707 -- already has a Packed_Array_Type representation defined, then
2708 -- replace this attribute with a direct reference to 'Range_Length
2709 -- of the appropriate index subtype (since otherwise the back end
2710 -- will try to give us the value of 'Length for this
2711 -- implementation type).
2713 elsif Is_Constrained (Ptyp) then
2715 Make_Attribute_Reference (Loc,
2716 Attribute_Name => Name_Range_Length,
2717 Prefix => New_Reference_To (Ityp, Loc)));
2718 Analyze_And_Resolve (N, Typ);
2723 elsif Is_Access_Type (Ptyp) then
2724 Apply_Access_Check (N);
2726 -- If the designated type is a packed array type, then we convert
2727 -- the reference to:
2730 -- xtyp'Pos (Pref'Last (Expr)) -
2731 -- xtyp'Pos (Pref'First (Expr)));
2733 -- This is a bit complex, but it is the easiest thing to do that
2734 -- works in all cases including enum types with holes xtyp here
2735 -- is the appropriate index type.
2738 Dtyp : constant Entity_Id := Designated_Type (Ptyp);
2742 if Is_Array_Type (Dtyp) and then Is_Packed (Dtyp) then
2743 Xtyp := Get_Index_Subtype (N);
2746 Make_Attribute_Reference (Loc,
2747 Prefix => New_Occurrence_Of (Typ, Loc),
2748 Attribute_Name => Name_Max,
2749 Expressions => New_List (
2750 Make_Integer_Literal (Loc, 0),
2753 Make_Integer_Literal (Loc, 1),
2754 Make_Op_Subtract (Loc,
2756 Make_Attribute_Reference (Loc,
2757 Prefix => New_Occurrence_Of (Xtyp, Loc),
2758 Attribute_Name => Name_Pos,
2759 Expressions => New_List (
2760 Make_Attribute_Reference (Loc,
2761 Prefix => Duplicate_Subexpr (Pref),
2762 Attribute_Name => Name_Last,
2764 New_Copy_List (Exprs)))),
2767 Make_Attribute_Reference (Loc,
2768 Prefix => New_Occurrence_Of (Xtyp, Loc),
2769 Attribute_Name => Name_Pos,
2770 Expressions => New_List (
2771 Make_Attribute_Reference (Loc,
2773 Duplicate_Subexpr_No_Checks (Pref),
2774 Attribute_Name => Name_First,
2776 New_Copy_List (Exprs)))))))));
2778 Analyze_And_Resolve (N, Typ);
2782 -- Otherwise leave it to the back end
2785 Apply_Universal_Integer_Attribute_Checks (N);
2793 -- Transforms 'Machine into a call to the floating-point attribute
2794 -- function Machine in Fat_xxx (where xxx is the root type)
2796 when Attribute_Machine =>
2797 Expand_Fpt_Attribute_R (N);
2799 ----------------------
2800 -- Machine_Rounding --
2801 ----------------------
2803 -- Transforms 'Machine_Rounding into a call to the floating-point
2804 -- attribute function Machine_Rounding in Fat_xxx (where xxx is the root
2805 -- type). Expansion is avoided for cases the back end can handle
2808 when Attribute_Machine_Rounding =>
2809 if not Is_Inline_Floating_Point_Attribute (N) then
2810 Expand_Fpt_Attribute_R (N);
2817 -- Machine_Size is equivalent to Object_Size, so transform it into
2818 -- Object_Size and that way the back end never sees Machine_Size.
2820 when Attribute_Machine_Size =>
2822 Make_Attribute_Reference (Loc,
2823 Prefix => Prefix (N),
2824 Attribute_Name => Name_Object_Size));
2826 Analyze_And_Resolve (N, Typ);
2832 -- The only case that can get this far is the dynamic case of the old
2833 -- Ada 83 Mantissa attribute for the fixed-point case. For this case,
2840 -- ityp (System.Mantissa.Mantissa_Value
2841 -- (Integer'Integer_Value (typ'First),
2842 -- Integer'Integer_Value (typ'Last)));
2844 when Attribute_Mantissa => Mantissa : begin
2847 Make_Function_Call (Loc,
2848 Name => New_Occurrence_Of (RTE (RE_Mantissa_Value), Loc),
2850 Parameter_Associations => New_List (
2852 Make_Attribute_Reference (Loc,
2853 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2854 Attribute_Name => Name_Integer_Value,
2855 Expressions => New_List (
2857 Make_Attribute_Reference (Loc,
2858 Prefix => New_Occurrence_Of (Ptyp, Loc),
2859 Attribute_Name => Name_First))),
2861 Make_Attribute_Reference (Loc,
2862 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2863 Attribute_Name => Name_Integer_Value,
2864 Expressions => New_List (
2866 Make_Attribute_Reference (Loc,
2867 Prefix => New_Occurrence_Of (Ptyp, Loc),
2868 Attribute_Name => Name_Last)))))));
2870 Analyze_And_Resolve (N, Typ);
2873 --------------------
2874 -- Mechanism_Code --
2875 --------------------
2877 when Attribute_Mechanism_Code =>
2879 -- We must replace the prefix in the renamed case
2881 if Is_Entity_Name (Pref)
2882 and then Present (Alias (Entity (Pref)))
2884 Set_Renamed_Subprogram (Pref, Alias (Entity (Pref)));
2891 when Attribute_Mod => Mod_Case : declare
2892 Arg : constant Node_Id := Relocate_Node (First (Exprs));
2893 Hi : constant Node_Id := Type_High_Bound (Etype (Arg));
2894 Modv : constant Uint := Modulus (Btyp);
2898 -- This is not so simple. The issue is what type to use for the
2899 -- computation of the modular value.
2901 -- The easy case is when the modulus value is within the bounds
2902 -- of the signed integer type of the argument. In this case we can
2903 -- just do the computation in that signed integer type, and then
2904 -- do an ordinary conversion to the target type.
2906 if Modv <= Expr_Value (Hi) then
2911 Right_Opnd => Make_Integer_Literal (Loc, Modv))));
2913 -- Here we know that the modulus is larger than type'Last of the
2914 -- integer type. There are two cases to consider:
2916 -- a) The integer value is non-negative. In this case, it is
2917 -- returned as the result (since it is less than the modulus).
2919 -- b) The integer value is negative. In this case, we know that the
2920 -- result is modulus + value, where the value might be as small as
2921 -- -modulus. The trouble is what type do we use to do the subtract.
2922 -- No type will do, since modulus can be as big as 2**64, and no
2923 -- integer type accommodates this value. Let's do bit of algebra
2926 -- = modulus - (-value)
2927 -- = (modulus - 1) - (-value - 1)
2929 -- Now modulus - 1 is certainly in range of the modular type.
2930 -- -value is in the range 1 .. modulus, so -value -1 is in the
2931 -- range 0 .. modulus-1 which is in range of the modular type.
2932 -- Furthermore, (-value - 1) can be expressed as -(value + 1)
2933 -- which we can compute using the integer base type.
2935 -- Once this is done we analyze the conditional expression without
2936 -- range checks, because we know everything is in range, and we
2937 -- want to prevent spurious warnings on either branch.
2941 Make_Conditional_Expression (Loc,
2942 Expressions => New_List (
2944 Left_Opnd => Duplicate_Subexpr (Arg),
2945 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2948 Duplicate_Subexpr_No_Checks (Arg)),
2950 Make_Op_Subtract (Loc,
2952 Make_Integer_Literal (Loc,
2953 Intval => Modv - 1),
2959 Left_Opnd => Duplicate_Subexpr_No_Checks (Arg),
2961 Make_Integer_Literal (Loc,
2962 Intval => 1))))))));
2966 Analyze_And_Resolve (N, Btyp, Suppress => All_Checks);
2973 -- Transforms 'Model into a call to the floating-point attribute
2974 -- function Model in Fat_xxx (where xxx is the root type)
2976 when Attribute_Model =>
2977 Expand_Fpt_Attribute_R (N);
2983 -- The processing for Object_Size shares the processing for Size
2989 when Attribute_Old => Old : declare
2990 Tnn : constant Entity_Id :=
2991 Make_Defining_Identifier (Loc,
2992 Chars => New_Internal_Name ('T'));
2997 -- Find the nearest subprogram body, ignoring _Preconditions
3001 Subp := Parent (Subp);
3002 exit when Nkind (Subp) = N_Subprogram_Body
3003 and then Chars (Defining_Entity (Subp)) /= Name_uPostconditions;
3006 -- Insert the assignment at the start of the declarations
3009 Make_Object_Declaration (Loc,
3010 Defining_Identifier => Tnn,
3011 Constant_Present => True,
3012 Object_Definition => New_Occurrence_Of (Etype (N), Loc),
3013 Expression => Pref);
3015 if Is_Empty_List (Declarations (Subp)) then
3016 Set_Declarations (Subp, New_List (Asn_Stm));
3019 Insert_Action (First (Declarations (Subp)), Asn_Stm);
3022 Rewrite (N, New_Occurrence_Of (Tnn, Loc));
3029 when Attribute_Output => Output : declare
3030 P_Type : constant Entity_Id := Entity (Pref);
3031 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3039 -- If no underlying type, we have an error that will be diagnosed
3040 -- elsewhere, so here we just completely ignore the expansion.
3046 -- If TSS for Output is present, just call it
3048 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Output);
3050 if Present (Pname) then
3054 -- If there is a Stream_Convert pragma, use it, we rewrite
3056 -- sourcetyp'Output (stream, Item)
3060 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
3062 -- where strmwrite is the given Write function that converts an
3063 -- argument of type sourcetyp or a type acctyp, from which it is
3064 -- derived to type strmtyp. The conversion to acttyp is required
3065 -- for the derived case.
3067 Prag := Get_Stream_Convert_Pragma (P_Type);
3069 if Present (Prag) then
3071 Next (Next (First (Pragma_Argument_Associations (Prag))));
3072 Wfunc := Entity (Expression (Arg3));
3075 Make_Attribute_Reference (Loc,
3076 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
3077 Attribute_Name => Name_Output,
3078 Expressions => New_List (
3079 Relocate_Node (First (Exprs)),
3080 Make_Function_Call (Loc,
3081 Name => New_Occurrence_Of (Wfunc, Loc),
3082 Parameter_Associations => New_List (
3083 OK_Convert_To (Etype (First_Formal (Wfunc)),
3084 Relocate_Node (Next (First (Exprs)))))))));
3089 -- For elementary types, we call the W_xxx routine directly.
3090 -- Note that the effect of Write and Output is identical for
3091 -- the case of an elementary type, since there are no
3092 -- discriminants or bounds.
3094 elsif Is_Elementary_Type (U_Type) then
3096 -- A special case arises if we have a defined _Write routine,
3097 -- since in this case we are required to call this routine.
3099 if Present (TSS (Base_Type (U_Type), TSS_Stream_Write)) then
3100 Build_Record_Or_Elementary_Output_Procedure
3101 (Loc, U_Type, Decl, Pname);
3102 Insert_Action (N, Decl);
3104 -- For normal cases, we call the W_xxx routine directly
3107 Rewrite (N, Build_Elementary_Write_Call (N));
3114 elsif Is_Array_Type (U_Type) then
3115 Build_Array_Output_Procedure (Loc, U_Type, Decl, Pname);
3116 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3118 -- Class-wide case, first output external tag, then dispatch
3119 -- to the appropriate primitive Output function (RM 13.13.2(31)).
3121 elsif Is_Class_Wide_Type (P_Type) then
3123 -- No need to do anything else compiling under restriction
3124 -- No_Dispatching_Calls. During the semantic analysis we
3125 -- already notified such violation.
3127 if Restriction_Active (No_Dispatching_Calls) then
3132 Strm : constant Node_Id := First (Exprs);
3133 Item : constant Node_Id := Next (Strm);
3136 -- Ada 2005 (AI-344): Check that the accessibility level
3137 -- of the type of the output object is not deeper than
3138 -- that of the attribute's prefix type.
3140 -- if Get_Access_Level (Item'Tag)
3141 -- /= Get_Access_Level (P_Type'Tag)
3146 -- String'Output (Strm, External_Tag (Item'Tag));
3148 -- We cannot figure out a practical way to implement this
3149 -- accessibility check on virtual machines, so we omit it.
3151 if Ada_Version >= Ada_05
3152 and then Tagged_Type_Expansion
3155 Make_Implicit_If_Statement (N,
3159 Build_Get_Access_Level (Loc,
3160 Make_Attribute_Reference (Loc,
3163 Duplicate_Subexpr (Item,
3165 Attribute_Name => Name_Tag)),
3168 Make_Integer_Literal (Loc,
3169 Type_Access_Level (P_Type))),
3172 New_List (Make_Raise_Statement (Loc,
3174 RTE (RE_Tag_Error), Loc)))));
3178 Make_Attribute_Reference (Loc,
3179 Prefix => New_Occurrence_Of (Standard_String, Loc),
3180 Attribute_Name => Name_Output,
3181 Expressions => New_List (
3182 Relocate_Node (Duplicate_Subexpr (Strm)),
3183 Make_Function_Call (Loc,
3185 New_Occurrence_Of (RTE (RE_External_Tag), Loc),
3186 Parameter_Associations => New_List (
3187 Make_Attribute_Reference (Loc,
3190 (Duplicate_Subexpr (Item, Name_Req => True)),
3191 Attribute_Name => Name_Tag))))));
3194 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
3196 -- Tagged type case, use the primitive Output function
3198 elsif Is_Tagged_Type (U_Type) then
3199 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
3201 -- All other record type cases, including protected records.
3202 -- The latter only arise for expander generated code for
3203 -- handling shared passive partition access.
3207 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3209 -- Ada 2005 (AI-216): Program_Error is raised when executing
3210 -- the default implementation of the Output attribute of an
3211 -- unchecked union type if the type lacks default discriminant
3214 if Is_Unchecked_Union (Base_Type (U_Type))
3215 and then No (Discriminant_Constraint (U_Type))
3218 Make_Raise_Program_Error (Loc,
3219 Reason => PE_Unchecked_Union_Restriction));
3224 Build_Record_Or_Elementary_Output_Procedure
3225 (Loc, Base_Type (U_Type), Decl, Pname);
3226 Insert_Action (N, Decl);
3230 -- If we fall through, Pname is the name of the procedure to call
3232 Rewrite_Stream_Proc_Call (Pname);
3239 -- For enumeration types with a standard representation, Pos is
3240 -- handled by the back end.
3242 -- For enumeration types, with a non-standard representation we
3243 -- generate a call to the _Rep_To_Pos function created when the
3244 -- type was frozen. The call has the form
3246 -- _rep_to_pos (expr, flag)
3248 -- The parameter flag is True if range checks are enabled, causing
3249 -- Program_Error to be raised if the expression has an invalid
3250 -- representation, and False if range checks are suppressed.
3252 -- For integer types, Pos is equivalent to a simple integer
3253 -- conversion and we rewrite it as such
3255 when Attribute_Pos => Pos :
3257 Etyp : Entity_Id := Base_Type (Entity (Pref));
3260 -- Deal with zero/non-zero boolean values
3262 if Is_Boolean_Type (Etyp) then
3263 Adjust_Condition (First (Exprs));
3264 Etyp := Standard_Boolean;
3265 Set_Prefix (N, New_Occurrence_Of (Standard_Boolean, Loc));
3268 -- Case of enumeration type
3270 if Is_Enumeration_Type (Etyp) then
3272 -- Non-standard enumeration type (generate call)
3274 if Present (Enum_Pos_To_Rep (Etyp)) then
3275 Append_To (Exprs, Rep_To_Pos_Flag (Etyp, Loc));
3278 Make_Function_Call (Loc,
3280 New_Reference_To (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3281 Parameter_Associations => Exprs)));
3283 Analyze_And_Resolve (N, Typ);
3285 -- Standard enumeration type (do universal integer check)
3288 Apply_Universal_Integer_Attribute_Checks (N);
3291 -- Deal with integer types (replace by conversion)
3293 elsif Is_Integer_Type (Etyp) then
3294 Rewrite (N, Convert_To (Typ, First (Exprs)));
3295 Analyze_And_Resolve (N, Typ);
3304 -- We compute this if a component clause was present, otherwise we leave
3305 -- the computation up to the back end, since we don't know what layout
3308 when Attribute_Position => Position :
3310 CE : constant Entity_Id := Entity (Selector_Name (Pref));
3313 if Present (Component_Clause (CE)) then
3315 Make_Integer_Literal (Loc,
3316 Intval => Component_Bit_Offset (CE) / System_Storage_Unit));
3317 Analyze_And_Resolve (N, Typ);
3320 Apply_Universal_Integer_Attribute_Checks (N);
3328 -- 1. Deal with enumeration types with holes
3329 -- 2. For floating-point, generate call to attribute function
3330 -- 3. For other cases, deal with constraint checking
3332 when Attribute_Pred => Pred :
3334 Etyp : constant Entity_Id := Base_Type (Ptyp);
3338 -- For enumeration types with non-standard representations, we
3339 -- expand typ'Pred (x) into
3341 -- Pos_To_Rep (Rep_To_Pos (x) - 1)
3343 -- If the representation is contiguous, we compute instead
3344 -- Lit1 + Rep_to_Pos (x -1), to catch invalid representations.
3345 -- The conversion function Enum_Pos_To_Rep is defined on the
3346 -- base type, not the subtype, so we have to use the base type
3347 -- explicitly for this and other enumeration attributes.
3349 if Is_Enumeration_Type (Ptyp)
3350 and then Present (Enum_Pos_To_Rep (Etyp))
3352 if Has_Contiguous_Rep (Etyp) then
3354 Unchecked_Convert_To (Ptyp,
3357 Make_Integer_Literal (Loc,
3358 Enumeration_Rep (First_Literal (Ptyp))),
3360 Make_Function_Call (Loc,
3363 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3365 Parameter_Associations =>
3367 Unchecked_Convert_To (Ptyp,
3368 Make_Op_Subtract (Loc,
3370 Unchecked_Convert_To (Standard_Integer,
3371 Relocate_Node (First (Exprs))),
3373 Make_Integer_Literal (Loc, 1))),
3374 Rep_To_Pos_Flag (Ptyp, Loc))))));
3377 -- Add Boolean parameter True, to request program errror if
3378 -- we have a bad representation on our hands. If checks are
3379 -- suppressed, then add False instead
3381 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
3383 Make_Indexed_Component (Loc,
3386 (Enum_Pos_To_Rep (Etyp), Loc),
3387 Expressions => New_List (
3388 Make_Op_Subtract (Loc,
3390 Make_Function_Call (Loc,
3393 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3394 Parameter_Associations => Exprs),
3395 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
3398 Analyze_And_Resolve (N, Typ);
3400 -- For floating-point, we transform 'Pred into a call to the Pred
3401 -- floating-point attribute function in Fat_xxx (xxx is root type)
3403 elsif Is_Floating_Point_Type (Ptyp) then
3404 Expand_Fpt_Attribute_R (N);
3405 Analyze_And_Resolve (N, Typ);
3407 -- For modular types, nothing to do (no overflow, since wraps)
3409 elsif Is_Modular_Integer_Type (Ptyp) then
3412 -- For other types, if argument is marked as needing a range check or
3413 -- overflow checking is enabled, we must generate a check.
3415 elsif not Overflow_Checks_Suppressed (Ptyp)
3416 or else Do_Range_Check (First (Exprs))
3418 Set_Do_Range_Check (First (Exprs), False);
3419 Expand_Pred_Succ (N);
3427 -- Ada 2005 (AI-327): Dynamic ceiling priorities
3429 -- We rewrite X'Priority as the following run-time call:
3431 -- Get_Ceiling (X._Object)
3433 -- Note that although X'Priority is notionally an object, it is quite
3434 -- deliberately not defined as an aliased object in the RM. This means
3435 -- that it works fine to rewrite it as a call, without having to worry
3436 -- about complications that would other arise from X'Priority'Access,
3437 -- which is illegal, because of the lack of aliasing.
3439 when Attribute_Priority =>
3442 Conctyp : Entity_Id;
3443 Object_Parm : Node_Id;
3445 RT_Subprg_Name : Node_Id;
3448 -- Look for the enclosing concurrent type
3450 Conctyp := Current_Scope;
3451 while not Is_Concurrent_Type (Conctyp) loop
3452 Conctyp := Scope (Conctyp);
3455 pragma Assert (Is_Protected_Type (Conctyp));
3457 -- Generate the actual of the call
3459 Subprg := Current_Scope;
3460 while not Present (Protected_Body_Subprogram (Subprg)) loop
3461 Subprg := Scope (Subprg);
3464 -- Use of 'Priority inside protected entries and barriers (in
3465 -- both cases the type of the first formal of their expanded
3466 -- subprogram is Address)
3468 if Etype (First_Entity (Protected_Body_Subprogram (Subprg)))
3472 New_Itype : Entity_Id;
3475 -- In the expansion of protected entries the type of the
3476 -- first formal of the Protected_Body_Subprogram is an
3477 -- Address. In order to reference the _object component
3480 -- type T is access p__ptTV;
3483 New_Itype := Create_Itype (E_Access_Type, N);
3484 Set_Etype (New_Itype, New_Itype);
3485 Set_Directly_Designated_Type (New_Itype,
3486 Corresponding_Record_Type (Conctyp));
3487 Freeze_Itype (New_Itype, N);
3490 -- T!(O)._object'unchecked_access
3493 Make_Attribute_Reference (Loc,
3495 Make_Selected_Component (Loc,
3497 Unchecked_Convert_To (New_Itype,
3500 (Protected_Body_Subprogram (Subprg)),
3503 Make_Identifier (Loc, Name_uObject)),
3504 Attribute_Name => Name_Unchecked_Access);
3507 -- Use of 'Priority inside a protected subprogram
3511 Make_Attribute_Reference (Loc,
3513 Make_Selected_Component (Loc,
3514 Prefix => New_Reference_To
3516 (Protected_Body_Subprogram (Subprg)),
3519 Make_Identifier (Loc, Name_uObject)),
3520 Attribute_Name => Name_Unchecked_Access);
3523 -- Select the appropriate run-time subprogram
3525 if Number_Entries (Conctyp) = 0 then
3527 New_Reference_To (RTE (RE_Get_Ceiling), Loc);
3530 New_Reference_To (RTE (RO_PE_Get_Ceiling), Loc);
3534 Make_Function_Call (Loc,
3535 Name => RT_Subprg_Name,
3536 Parameter_Associations => New_List (Object_Parm));
3540 -- Avoid the generation of extra checks on the pointer to the
3541 -- protected object.
3543 Analyze_And_Resolve (N, Typ, Suppress => Access_Check);
3550 when Attribute_Range_Length => Range_Length : begin
3551 -- The only special processing required is for the case where
3552 -- Range_Length is applied to an enumeration type with holes.
3553 -- In this case we transform
3559 -- X'Pos (X'Last) - X'Pos (X'First) + 1
3561 -- So that the result reflects the proper Pos values instead
3562 -- of the underlying representations.
3564 if Is_Enumeration_Type (Ptyp)
3565 and then Has_Non_Standard_Rep (Ptyp)
3570 Make_Op_Subtract (Loc,
3572 Make_Attribute_Reference (Loc,
3573 Attribute_Name => Name_Pos,
3574 Prefix => New_Occurrence_Of (Ptyp, Loc),
3575 Expressions => New_List (
3576 Make_Attribute_Reference (Loc,
3577 Attribute_Name => Name_Last,
3578 Prefix => New_Occurrence_Of (Ptyp, Loc)))),
3581 Make_Attribute_Reference (Loc,
3582 Attribute_Name => Name_Pos,
3583 Prefix => New_Occurrence_Of (Ptyp, Loc),
3584 Expressions => New_List (
3585 Make_Attribute_Reference (Loc,
3586 Attribute_Name => Name_First,
3587 Prefix => New_Occurrence_Of (Ptyp, Loc))))),
3590 Make_Integer_Literal (Loc, 1)));
3592 Analyze_And_Resolve (N, Typ);
3594 -- For all other cases, the attribute is handled by the back end, but
3595 -- we need to deal with the case of the range check on a universal
3599 Apply_Universal_Integer_Attribute_Checks (N);
3607 when Attribute_Read => Read : declare
3608 P_Type : constant Entity_Id := Entity (Pref);
3609 B_Type : constant Entity_Id := Base_Type (P_Type);
3610 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3620 -- If no underlying type, we have an error that will be diagnosed
3621 -- elsewhere, so here we just completely ignore the expansion.
3627 -- The simple case, if there is a TSS for Read, just call it
3629 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Read);
3631 if Present (Pname) then
3635 -- If there is a Stream_Convert pragma, use it, we rewrite
3637 -- sourcetyp'Read (stream, Item)
3641 -- Item := sourcetyp (strmread (strmtyp'Input (Stream)));
3643 -- where strmread is the given Read function that converts an
3644 -- argument of type strmtyp to type sourcetyp or a type from which
3645 -- it is derived. The conversion to sourcetyp is required in the
3648 -- A special case arises if Item is a type conversion in which
3649 -- case, we have to expand to:
3651 -- Itemx := typex (strmread (strmtyp'Input (Stream)));
3653 -- where Itemx is the expression of the type conversion (i.e.
3654 -- the actual object), and typex is the type of Itemx.
3656 Prag := Get_Stream_Convert_Pragma (P_Type);
3658 if Present (Prag) then
3659 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
3660 Rfunc := Entity (Expression (Arg2));
3661 Lhs := Relocate_Node (Next (First (Exprs)));
3663 OK_Convert_To (B_Type,
3664 Make_Function_Call (Loc,
3665 Name => New_Occurrence_Of (Rfunc, Loc),
3666 Parameter_Associations => New_List (
3667 Make_Attribute_Reference (Loc,
3670 (Etype (First_Formal (Rfunc)), Loc),
3671 Attribute_Name => Name_Input,
3672 Expressions => New_List (
3673 Relocate_Node (First (Exprs)))))));
3675 if Nkind (Lhs) = N_Type_Conversion then
3676 Lhs := Expression (Lhs);
3677 Rhs := Convert_To (Etype (Lhs), Rhs);
3681 Make_Assignment_Statement (Loc,
3683 Expression => Rhs));
3684 Set_Assignment_OK (Lhs);
3688 -- For elementary types, we call the I_xxx routine using the first
3689 -- parameter and then assign the result into the second parameter.
3690 -- We set Assignment_OK to deal with the conversion case.
3692 elsif Is_Elementary_Type (U_Type) then
3698 Lhs := Relocate_Node (Next (First (Exprs)));
3699 Rhs := Build_Elementary_Input_Call (N);
3701 if Nkind (Lhs) = N_Type_Conversion then
3702 Lhs := Expression (Lhs);
3703 Rhs := Convert_To (Etype (Lhs), Rhs);
3706 Set_Assignment_OK (Lhs);
3709 Make_Assignment_Statement (Loc,
3711 Expression => Rhs));
3719 elsif Is_Array_Type (U_Type) then
3720 Build_Array_Read_Procedure (N, U_Type, Decl, Pname);
3721 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3723 -- Tagged type case, use the primitive Read function. Note that
3724 -- this will dispatch in the class-wide case which is what we want
3726 elsif Is_Tagged_Type (U_Type) then
3727 Pname := Find_Prim_Op (U_Type, TSS_Stream_Read);
3729 -- All other record type cases, including protected records. The
3730 -- latter only arise for expander generated code for handling
3731 -- shared passive partition access.
3735 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3737 -- Ada 2005 (AI-216): Program_Error is raised when executing
3738 -- the default implementation of the Read attribute of an
3739 -- Unchecked_Union type.
3741 if Is_Unchecked_Union (Base_Type (U_Type)) then
3743 Make_Raise_Program_Error (Loc,
3744 Reason => PE_Unchecked_Union_Restriction));
3747 if Has_Discriminants (U_Type)
3749 (Discriminant_Default_Value (First_Discriminant (U_Type)))
3751 Build_Mutable_Record_Read_Procedure
3752 (Loc, Base_Type (U_Type), Decl, Pname);
3754 Build_Record_Read_Procedure
3755 (Loc, Base_Type (U_Type), Decl, Pname);
3758 -- Suppress checks, uninitialized or otherwise invalid
3759 -- data does not cause constraint errors to be raised for
3760 -- a complete record read.
3762 Insert_Action (N, Decl, All_Checks);
3766 Rewrite_Stream_Proc_Call (Pname);
3773 -- Transforms 'Remainder into a call to the floating-point attribute
3774 -- function Remainder in Fat_xxx (where xxx is the root type)
3776 when Attribute_Remainder =>
3777 Expand_Fpt_Attribute_RR (N);
3783 -- Transform 'Result into reference to _Result formal. At the point
3784 -- where a legal 'Result attribute is expanded, we know that we are in
3785 -- the context of a _Postcondition function with a _Result parameter.
3787 when Attribute_Result =>
3789 Make_Identifier (Loc,
3790 Chars => Name_uResult));
3791 Analyze_And_Resolve (N, Typ);
3797 -- The handling of the Round attribute is quite delicate. The processing
3798 -- in Sem_Attr introduced a conversion to universal real, reflecting the
3799 -- semantics of Round, but we do not want anything to do with universal
3800 -- real at runtime, since this corresponds to using floating-point
3803 -- What we have now is that the Etype of the Round attribute correctly
3804 -- indicates the final result type. The operand of the Round is the
3805 -- conversion to universal real, described above, and the operand of
3806 -- this conversion is the actual operand of Round, which may be the
3807 -- special case of a fixed point multiplication or division (Etype =
3810 -- The exapander will expand first the operand of the conversion, then
3811 -- the conversion, and finally the round attribute itself, since we
3812 -- always work inside out. But we cannot simply process naively in this
3813 -- order. In the semantic world where universal fixed and real really
3814 -- exist and have infinite precision, there is no problem, but in the
3815 -- implementation world, where universal real is a floating-point type,
3816 -- we would get the wrong result.
3818 -- So the approach is as follows. First, when expanding a multiply or
3819 -- divide whose type is universal fixed, we do nothing at all, instead
3820 -- deferring the operation till later.
3822 -- The actual processing is done in Expand_N_Type_Conversion which
3823 -- handles the special case of Round by looking at its parent to see if
3824 -- it is a Round attribute, and if it is, handling the conversion (or
3825 -- its fixed multiply/divide child) in an appropriate manner.
3827 -- This means that by the time we get to expanding the Round attribute
3828 -- itself, the Round is nothing more than a type conversion (and will
3829 -- often be a null type conversion), so we just replace it with the
3830 -- appropriate conversion operation.
3832 when Attribute_Round =>
3834 Convert_To (Etype (N), Relocate_Node (First (Exprs))));
3835 Analyze_And_Resolve (N);
3841 -- Transforms 'Rounding into a call to the floating-point attribute
3842 -- function Rounding in Fat_xxx (where xxx is the root type)
3844 when Attribute_Rounding =>
3845 Expand_Fpt_Attribute_R (N);
3851 -- Transforms 'Scaling into a call to the floating-point attribute
3852 -- function Scaling in Fat_xxx (where xxx is the root type)
3854 when Attribute_Scaling =>
3855 Expand_Fpt_Attribute_RI (N);
3861 when Attribute_Size |
3862 Attribute_Object_Size |
3863 Attribute_Value_Size |
3864 Attribute_VADS_Size => Size :
3871 -- Processing for VADS_Size case. Note that this processing removes
3872 -- all traces of VADS_Size from the tree, and completes all required
3873 -- processing for VADS_Size by translating the attribute reference
3874 -- to an appropriate Size or Object_Size reference.
3876 if Id = Attribute_VADS_Size
3877 or else (Use_VADS_Size and then Id = Attribute_Size)
3879 -- If the size is specified, then we simply use the specified
3880 -- size. This applies to both types and objects. The size of an
3881 -- object can be specified in the following ways:
3883 -- An explicit size object is given for an object
3884 -- A component size is specified for an indexed component
3885 -- A component clause is specified for a selected component
3886 -- The object is a component of a packed composite object
3888 -- If the size is specified, then VADS_Size of an object
3890 if (Is_Entity_Name (Pref)
3891 and then Present (Size_Clause (Entity (Pref))))
3893 (Nkind (Pref) = N_Component_Clause
3894 and then (Present (Component_Clause
3895 (Entity (Selector_Name (Pref))))
3896 or else Is_Packed (Etype (Prefix (Pref)))))
3898 (Nkind (Pref) = N_Indexed_Component
3899 and then (Component_Size (Etype (Prefix (Pref))) /= 0
3900 or else Is_Packed (Etype (Prefix (Pref)))))
3902 Set_Attribute_Name (N, Name_Size);
3904 -- Otherwise if we have an object rather than a type, then the
3905 -- VADS_Size attribute applies to the type of the object, rather
3906 -- than the object itself. This is one of the respects in which
3907 -- VADS_Size differs from Size.
3910 if (not Is_Entity_Name (Pref)
3911 or else not Is_Type (Entity (Pref)))
3912 and then (Is_Scalar_Type (Ptyp) or else Is_Constrained (Ptyp))
3914 Rewrite (Pref, New_Occurrence_Of (Ptyp, Loc));
3917 -- For a scalar type for which no size was explicitly given,
3918 -- VADS_Size means Object_Size. This is the other respect in
3919 -- which VADS_Size differs from Size.
3921 if Is_Scalar_Type (Ptyp) and then No (Size_Clause (Ptyp)) then
3922 Set_Attribute_Name (N, Name_Object_Size);
3924 -- In all other cases, Size and VADS_Size are the sane
3927 Set_Attribute_Name (N, Name_Size);
3932 -- For class-wide types, X'Class'Size is transformed into a direct
3933 -- reference to the Size of the class type, so that the back end does
3934 -- not have to deal with the X'Class'Size reference.
3936 if Is_Entity_Name (Pref)
3937 and then Is_Class_Wide_Type (Entity (Pref))
3939 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
3942 -- For X'Size applied to an object of a class-wide type, transform
3943 -- X'Size into a call to the primitive operation _Size applied to X.
3945 elsif Is_Class_Wide_Type (Ptyp)
3946 or else (Id = Attribute_Size
3947 and then Is_Tagged_Type (Ptyp)
3948 and then Has_Unknown_Discriminants (Ptyp))
3950 -- No need to do anything else compiling under restriction
3951 -- No_Dispatching_Calls. During the semantic analysis we
3952 -- already notified such violation.
3954 if Restriction_Active (No_Dispatching_Calls) then
3959 Make_Function_Call (Loc,
3960 Name => New_Reference_To
3961 (Find_Prim_Op (Ptyp, Name_uSize), Loc),
3962 Parameter_Associations => New_List (Pref));
3964 if Typ /= Standard_Long_Long_Integer then
3966 -- The context is a specific integer type with which the
3967 -- original attribute was compatible. The function has a
3968 -- specific type as well, so to preserve the compatibility
3969 -- we must convert explicitly.
3971 New_Node := Convert_To (Typ, New_Node);
3974 Rewrite (N, New_Node);
3975 Analyze_And_Resolve (N, Typ);
3978 -- Case of known RM_Size of a type
3980 elsif (Id = Attribute_Size or else Id = Attribute_Value_Size)
3981 and then Is_Entity_Name (Pref)
3982 and then Is_Type (Entity (Pref))
3983 and then Known_Static_RM_Size (Entity (Pref))
3985 Siz := RM_Size (Entity (Pref));
3987 -- Case of known Esize of a type
3989 elsif Id = Attribute_Object_Size
3990 and then Is_Entity_Name (Pref)
3991 and then Is_Type (Entity (Pref))
3992 and then Known_Static_Esize (Entity (Pref))
3994 Siz := Esize (Entity (Pref));
3996 -- Case of known size of object
3998 elsif Id = Attribute_Size
3999 and then Is_Entity_Name (Pref)
4000 and then Is_Object (Entity (Pref))
4001 and then Known_Esize (Entity (Pref))
4002 and then Known_Static_Esize (Entity (Pref))
4004 Siz := Esize (Entity (Pref));
4006 -- For an array component, we can do Size in the front end
4007 -- if the component_size of the array is set.
4009 elsif Nkind (Pref) = N_Indexed_Component then
4010 Siz := Component_Size (Etype (Prefix (Pref)));
4012 -- For a record component, we can do Size in the front end if there
4013 -- is a component clause, or if the record is packed and the
4014 -- component's size is known at compile time.
4016 elsif Nkind (Pref) = N_Selected_Component then
4018 Rec : constant Entity_Id := Etype (Prefix (Pref));
4019 Comp : constant Entity_Id := Entity (Selector_Name (Pref));
4022 if Present (Component_Clause (Comp)) then
4023 Siz := Esize (Comp);
4025 elsif Is_Packed (Rec) then
4026 Siz := RM_Size (Ptyp);
4029 Apply_Universal_Integer_Attribute_Checks (N);
4034 -- All other cases are handled by the back end
4037 Apply_Universal_Integer_Attribute_Checks (N);
4039 -- If Size is applied to a formal parameter that is of a packed
4040 -- array subtype, then apply Size to the actual subtype.
4042 if Is_Entity_Name (Pref)
4043 and then Is_Formal (Entity (Pref))
4044 and then Is_Array_Type (Ptyp)
4045 and then Is_Packed (Ptyp)
4048 Make_Attribute_Reference (Loc,
4050 New_Occurrence_Of (Get_Actual_Subtype (Pref), Loc),
4051 Attribute_Name => Name_Size));
4052 Analyze_And_Resolve (N, Typ);
4055 -- If Size applies to a dereference of an access to unconstrained
4056 -- packed array, the back end needs to see its unconstrained
4057 -- nominal type, but also a hint to the actual constrained type.
4059 if Nkind (Pref) = N_Explicit_Dereference
4060 and then Is_Array_Type (Ptyp)
4061 and then not Is_Constrained (Ptyp)
4062 and then Is_Packed (Ptyp)
4064 Set_Actual_Designated_Subtype (Pref,
4065 Get_Actual_Subtype (Pref));
4071 -- Common processing for record and array component case
4073 if Siz /= No_Uint and then Siz /= 0 then
4075 CS : constant Boolean := Comes_From_Source (N);
4078 Rewrite (N, Make_Integer_Literal (Loc, Siz));
4080 -- This integer literal is not a static expression. We do not
4081 -- call Analyze_And_Resolve here, because this would activate
4082 -- the circuit for deciding that a static value was out of
4083 -- range, and we don't want that.
4085 -- So just manually set the type, mark the expression as non-
4086 -- static, and then ensure that the result is checked properly
4087 -- if the attribute comes from source (if it was internally
4088 -- generated, we never need a constraint check).
4091 Set_Is_Static_Expression (N, False);
4094 Apply_Constraint_Check (N, Typ);
4104 when Attribute_Storage_Pool =>
4106 Make_Type_Conversion (Loc,
4107 Subtype_Mark => New_Reference_To (Etype (N), Loc),
4108 Expression => New_Reference_To (Entity (N), Loc)));
4109 Analyze_And_Resolve (N, Typ);
4115 when Attribute_Storage_Size => Storage_Size : begin
4117 -- Access type case, always go to the root type
4119 -- The case of access types results in a value of zero for the case
4120 -- where no storage size attribute clause has been given. If a
4121 -- storage size has been given, then the attribute is converted
4122 -- to a reference to the variable used to hold this value.
4124 if Is_Access_Type (Ptyp) then
4125 if Present (Storage_Size_Variable (Root_Type (Ptyp))) then
4127 Make_Attribute_Reference (Loc,
4128 Prefix => New_Reference_To (Typ, Loc),
4129 Attribute_Name => Name_Max,
4130 Expressions => New_List (
4131 Make_Integer_Literal (Loc, 0),
4134 (Storage_Size_Variable (Root_Type (Ptyp)), Loc)))));
4136 elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then
4139 Make_Function_Call (Loc,
4143 (Etype (Associated_Storage_Pool (Root_Type (Ptyp))),
4144 Attribute_Name (N)),
4147 Parameter_Associations => New_List (
4149 (Associated_Storage_Pool (Root_Type (Ptyp)), Loc)))));
4152 Rewrite (N, Make_Integer_Literal (Loc, 0));
4155 Analyze_And_Resolve (N, Typ);
4157 -- For tasks, we retrieve the size directly from the TCB. The
4158 -- size may depend on a discriminant of the type, and therefore
4159 -- can be a per-object expression, so type-level information is
4160 -- not sufficient in general. There are four cases to consider:
4162 -- a) If the attribute appears within a task body, the designated
4163 -- TCB is obtained by a call to Self.
4165 -- b) If the prefix of the attribute is the name of a task object,
4166 -- the designated TCB is the one stored in the corresponding record.
4168 -- c) If the prefix is a task type, the size is obtained from the
4169 -- size variable created for each task type
4171 -- d) If no storage_size was specified for the type , there is no
4172 -- size variable, and the value is a system-specific default.
4175 if In_Open_Scopes (Ptyp) then
4177 -- Storage_Size (Self)
4181 Make_Function_Call (Loc,
4183 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4184 Parameter_Associations =>
4186 Make_Function_Call (Loc,
4188 New_Reference_To (RTE (RE_Self), Loc))))));
4190 elsif not Is_Entity_Name (Pref)
4191 or else not Is_Type (Entity (Pref))
4193 -- Storage_Size (Rec (Obj).Size)
4197 Make_Function_Call (Loc,
4199 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4200 Parameter_Associations =>
4202 Make_Selected_Component (Loc,
4204 Unchecked_Convert_To (
4205 Corresponding_Record_Type (Ptyp),
4206 New_Copy_Tree (Pref)),
4208 Make_Identifier (Loc, Name_uTask_Id))))));
4210 elsif Present (Storage_Size_Variable (Ptyp)) then
4212 -- Static storage size pragma given for type: retrieve value
4213 -- from its allocated storage variable.
4217 Make_Function_Call (Loc,
4218 Name => New_Occurrence_Of (
4219 RTE (RE_Adjust_Storage_Size), Loc),
4220 Parameter_Associations =>
4223 Storage_Size_Variable (Ptyp), Loc)))));
4225 -- Get system default
4229 Make_Function_Call (Loc,
4232 RTE (RE_Default_Stack_Size), Loc))));
4235 Analyze_And_Resolve (N, Typ);
4243 when Attribute_Stream_Size => Stream_Size : declare
4247 -- If we have a Stream_Size clause for this type use it, otherwise
4248 -- the Stream_Size if the size of the type.
4250 if Has_Stream_Size_Clause (Ptyp) then
4253 (Static_Integer (Expression (Stream_Size_Clause (Ptyp))));
4255 Size := UI_To_Int (Esize (Ptyp));
4258 Rewrite (N, Make_Integer_Literal (Loc, Intval => Size));
4259 Analyze_And_Resolve (N, Typ);
4266 -- 1. Deal with enumeration types with holes
4267 -- 2. For floating-point, generate call to attribute function
4268 -- 3. For other cases, deal with constraint checking
4270 when Attribute_Succ => Succ :
4272 Etyp : constant Entity_Id := Base_Type (Ptyp);
4276 -- For enumeration types with non-standard representations, we
4277 -- expand typ'Succ (x) into
4279 -- Pos_To_Rep (Rep_To_Pos (x) + 1)
4281 -- If the representation is contiguous, we compute instead
4282 -- Lit1 + Rep_to_Pos (x+1), to catch invalid representations.
4284 if Is_Enumeration_Type (Ptyp)
4285 and then Present (Enum_Pos_To_Rep (Etyp))
4287 if Has_Contiguous_Rep (Etyp) then
4289 Unchecked_Convert_To (Ptyp,
4292 Make_Integer_Literal (Loc,
4293 Enumeration_Rep (First_Literal (Ptyp))),
4295 Make_Function_Call (Loc,
4298 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4300 Parameter_Associations =>
4302 Unchecked_Convert_To (Ptyp,
4305 Unchecked_Convert_To (Standard_Integer,
4306 Relocate_Node (First (Exprs))),
4308 Make_Integer_Literal (Loc, 1))),
4309 Rep_To_Pos_Flag (Ptyp, Loc))))));
4311 -- Add Boolean parameter True, to request program errror if
4312 -- we have a bad representation on our hands. Add False if
4313 -- checks are suppressed.
4315 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
4317 Make_Indexed_Component (Loc,
4320 (Enum_Pos_To_Rep (Etyp), Loc),
4321 Expressions => New_List (
4324 Make_Function_Call (Loc,
4327 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4328 Parameter_Associations => Exprs),
4329 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
4332 Analyze_And_Resolve (N, Typ);
4334 -- For floating-point, we transform 'Succ into a call to the Succ
4335 -- floating-point attribute function in Fat_xxx (xxx is root type)
4337 elsif Is_Floating_Point_Type (Ptyp) then
4338 Expand_Fpt_Attribute_R (N);
4339 Analyze_And_Resolve (N, Typ);
4341 -- For modular types, nothing to do (no overflow, since wraps)
4343 elsif Is_Modular_Integer_Type (Ptyp) then
4346 -- For other types, if argument is marked as needing a range check or
4347 -- overflow checking is enabled, we must generate a check.
4349 elsif not Overflow_Checks_Suppressed (Ptyp)
4350 or else Do_Range_Check (First (Exprs))
4352 Set_Do_Range_Check (First (Exprs), False);
4353 Expand_Pred_Succ (N);
4361 -- Transforms X'Tag into a direct reference to the tag of X
4363 when Attribute_Tag => Tag :
4366 Prefix_Is_Type : Boolean;
4369 if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then
4370 Ttyp := Entity (Pref);
4371 Prefix_Is_Type := True;
4374 Prefix_Is_Type := False;
4377 if Is_Class_Wide_Type (Ttyp) then
4378 Ttyp := Root_Type (Ttyp);
4381 Ttyp := Underlying_Type (Ttyp);
4383 -- Ada 2005: The type may be a synchronized tagged type, in which
4384 -- case the tag information is stored in the corresponding record.
4386 if Is_Concurrent_Type (Ttyp) then
4387 Ttyp := Corresponding_Record_Type (Ttyp);
4390 if Prefix_Is_Type then
4392 -- For VMs we leave the type attribute unexpanded because
4393 -- there's not a dispatching table to reference.
4395 if Tagged_Type_Expansion then
4397 Unchecked_Convert_To (RTE (RE_Tag),
4399 (Node (First_Elmt (Access_Disp_Table (Ttyp))), Loc)));
4400 Analyze_And_Resolve (N, RTE (RE_Tag));
4403 -- Ada 2005 (AI-251): The use of 'Tag in the sources always
4404 -- references the primary tag of the actual object. If 'Tag is
4405 -- applied to class-wide interface objects we generate code that
4406 -- displaces "this" to reference the base of the object.
4408 elsif Comes_From_Source (N)
4409 and then Is_Class_Wide_Type (Etype (Prefix (N)))
4410 and then Is_Interface (Etype (Prefix (N)))
4413 -- (To_Tag_Ptr (Prefix'Address)).all
4415 -- Note that Prefix'Address is recursively expanded into a call
4416 -- to Base_Address (Obj.Tag)
4418 -- Not needed for VM targets, since all handled by the VM
4420 if Tagged_Type_Expansion then
4422 Make_Explicit_Dereference (Loc,
4423 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
4424 Make_Attribute_Reference (Loc,
4425 Prefix => Relocate_Node (Pref),
4426 Attribute_Name => Name_Address))));
4427 Analyze_And_Resolve (N, RTE (RE_Tag));
4432 Make_Selected_Component (Loc,
4433 Prefix => Relocate_Node (Pref),
4435 New_Reference_To (First_Tag_Component (Ttyp), Loc)));
4436 Analyze_And_Resolve (N, RTE (RE_Tag));
4444 -- Transforms 'Terminated attribute into a call to Terminated function
4446 when Attribute_Terminated => Terminated :
4448 -- The prefix of Terminated is of a task interface class-wide type.
4450 -- terminated (Task_Id (Pref._disp_get_task_id));
4452 if Ada_Version >= Ada_05
4453 and then Ekind (Ptyp) = E_Class_Wide_Type
4454 and then Is_Interface (Ptyp)
4455 and then Is_Task_Interface (Ptyp)
4458 Make_Function_Call (Loc,
4460 New_Reference_To (RTE (RE_Terminated), Loc),
4461 Parameter_Associations => New_List (
4462 Make_Unchecked_Type_Conversion (Loc,
4464 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
4466 Make_Selected_Component (Loc,
4468 New_Copy_Tree (Pref),
4470 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
4472 elsif Restricted_Profile then
4474 Build_Call_With_Task (Pref, RTE (RE_Restricted_Terminated)));
4478 Build_Call_With_Task (Pref, RTE (RE_Terminated)));
4481 Analyze_And_Resolve (N, Standard_Boolean);
4488 -- Transforms System'To_Address (X) into unchecked conversion
4489 -- from (integral) type of X to type address.
4491 when Attribute_To_Address =>
4493 Unchecked_Convert_To (RTE (RE_Address),
4494 Relocate_Node (First (Exprs))));
4495 Analyze_And_Resolve (N, RTE (RE_Address));
4501 when Attribute_To_Any => To_Any : declare
4502 P_Type : constant Entity_Id := Etype (Pref);
4503 Decls : constant List_Id := New_List;
4507 (Convert_To (P_Type,
4508 Relocate_Node (First (Exprs))), Decls));
4509 Insert_Actions (N, Decls);
4510 Analyze_And_Resolve (N, RTE (RE_Any));
4517 -- Transforms 'Truncation into a call to the floating-point attribute
4518 -- function Truncation in Fat_xxx (where xxx is the root type).
4519 -- Expansion is avoided for cases the back end can handle directly.
4521 when Attribute_Truncation =>
4522 if not Is_Inline_Floating_Point_Attribute (N) then
4523 Expand_Fpt_Attribute_R (N);
4530 when Attribute_TypeCode => TypeCode : declare
4531 P_Type : constant Entity_Id := Etype (Pref);
4532 Decls : constant List_Id := New_List;
4534 Rewrite (N, Build_TypeCode_Call (Loc, P_Type, Decls));
4535 Insert_Actions (N, Decls);
4536 Analyze_And_Resolve (N, RTE (RE_TypeCode));
4539 -----------------------
4540 -- Unbiased_Rounding --
4541 -----------------------
4543 -- Transforms 'Unbiased_Rounding into a call to the floating-point
4544 -- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the
4545 -- root type). Expansion is avoided for cases the back end can handle
4548 when Attribute_Unbiased_Rounding =>
4549 if not Is_Inline_Floating_Point_Attribute (N) then
4550 Expand_Fpt_Attribute_R (N);
4557 when Attribute_UET_Address => UET_Address : declare
4558 Ent : constant Entity_Id :=
4559 Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
4563 Make_Object_Declaration (Loc,
4564 Defining_Identifier => Ent,
4565 Aliased_Present => True,
4566 Object_Definition =>
4567 New_Occurrence_Of (RTE (RE_Address), Loc)));
4569 -- Construct name __gnat_xxx__SDP, where xxx is the unit name
4570 -- in normal external form.
4572 Get_External_Unit_Name_String (Get_Unit_Name (Pref));
4573 Name_Buffer (1 + 7 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
4574 Name_Len := Name_Len + 7;
4575 Name_Buffer (1 .. 7) := "__gnat_";
4576 Name_Buffer (Name_Len + 1 .. Name_Len + 5) := "__SDP";
4577 Name_Len := Name_Len + 5;
4579 Set_Is_Imported (Ent);
4580 Set_Interface_Name (Ent,
4581 Make_String_Literal (Loc,
4582 Strval => String_From_Name_Buffer));
4584 -- Set entity as internal to ensure proper Sprint output of its
4585 -- implicit importation.
4587 Set_Is_Internal (Ent);
4590 Make_Attribute_Reference (Loc,
4591 Prefix => New_Occurrence_Of (Ent, Loc),
4592 Attribute_Name => Name_Address));
4594 Analyze_And_Resolve (N, Typ);
4601 -- The processing for VADS_Size is shared with Size
4607 -- For enumeration types with a standard representation, and for all
4608 -- other types, Val is handled by the back end. For enumeration types
4609 -- with a non-standard representation we use the _Pos_To_Rep array that
4610 -- was created when the type was frozen.
4612 when Attribute_Val => Val :
4614 Etyp : constant Entity_Id := Base_Type (Entity (Pref));
4617 if Is_Enumeration_Type (Etyp)
4618 and then Present (Enum_Pos_To_Rep (Etyp))
4620 if Has_Contiguous_Rep (Etyp) then
4622 Rep_Node : constant Node_Id :=
4623 Unchecked_Convert_To (Etyp,
4626 Make_Integer_Literal (Loc,
4627 Enumeration_Rep (First_Literal (Etyp))),
4629 (Convert_To (Standard_Integer,
4630 Relocate_Node (First (Exprs))))));
4634 Unchecked_Convert_To (Etyp,
4637 Make_Integer_Literal (Loc,
4638 Enumeration_Rep (First_Literal (Etyp))),
4640 Make_Function_Call (Loc,
4643 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4644 Parameter_Associations => New_List (
4646 Rep_To_Pos_Flag (Etyp, Loc))))));
4651 Make_Indexed_Component (Loc,
4652 Prefix => New_Reference_To (Enum_Pos_To_Rep (Etyp), Loc),
4653 Expressions => New_List (
4654 Convert_To (Standard_Integer,
4655 Relocate_Node (First (Exprs))))));
4658 Analyze_And_Resolve (N, Typ);
4660 -- If the argument is marked as requiring a range check then generate
4663 elsif Do_Range_Check (First (Exprs)) then
4664 Set_Do_Range_Check (First (Exprs), False);
4665 Generate_Range_Check (First (Exprs), Etyp, CE_Range_Check_Failed);
4673 -- The code for valid is dependent on the particular types involved.
4674 -- See separate sections below for the generated code in each case.
4676 when Attribute_Valid => Valid :
4678 Btyp : Entity_Id := Base_Type (Ptyp);
4681 Save_Validity_Checks_On : constant Boolean := Validity_Checks_On;
4682 -- Save the validity checking mode. We always turn off validity
4683 -- checking during process of 'Valid since this is one place
4684 -- where we do not want the implicit validity checks to intefere
4685 -- with the explicit validity check that the programmer is doing.
4687 function Make_Range_Test return Node_Id;
4688 -- Build the code for a range test of the form
4689 -- Btyp!(Pref) >= Btyp!(Ptyp'First)
4691 -- Btyp!(Pref) <= Btyp!(Ptyp'Last)
4693 ---------------------
4694 -- Make_Range_Test --
4695 ---------------------
4697 function Make_Range_Test return Node_Id is
4698 Temp : constant Node_Id := Duplicate_Subexpr (Pref);
4701 -- The value whose validity is being checked has been captured in
4702 -- an object declaration. We certainly don't want this object to
4703 -- appear valid because the declaration initializes it!
4705 if Is_Entity_Name (Temp) then
4706 Set_Is_Known_Valid (Entity (Temp), False);
4714 Unchecked_Convert_To (Btyp, Temp),
4717 Unchecked_Convert_To (Btyp,
4718 Make_Attribute_Reference (Loc,
4719 Prefix => New_Occurrence_Of (Ptyp, Loc),
4720 Attribute_Name => Name_First))),
4725 Unchecked_Convert_To (Btyp, Temp),
4728 Unchecked_Convert_To (Btyp,
4729 Make_Attribute_Reference (Loc,
4730 Prefix => New_Occurrence_Of (Ptyp, Loc),
4731 Attribute_Name => Name_Last))));
4732 end Make_Range_Test;
4734 -- Start of processing for Attribute_Valid
4737 -- Turn off validity checks. We do not want any implicit validity
4738 -- checks to intefere with the explicit check from the attribute
4740 Validity_Checks_On := False;
4742 -- Floating-point case. This case is handled by the Valid attribute
4743 -- code in the floating-point attribute run-time library.
4745 if Is_Floating_Point_Type (Ptyp) then
4751 -- For vax fpt types, call appropriate routine in special vax
4752 -- floating point unit. We do not have to worry about loads in
4753 -- this case, since these types have no signalling NaN's.
4755 if Vax_Float (Btyp) then
4756 Expand_Vax_Valid (N);
4758 -- The AAMP back end handles Valid for floating-point types
4760 elsif Is_AAMP_Float (Btyp) then
4761 Analyze_And_Resolve (Pref, Ptyp);
4762 Set_Etype (N, Standard_Boolean);
4765 -- Non VAX float case
4768 Find_Fat_Info (Ptyp, Ftp, Pkg);
4770 -- If the floating-point object might be unaligned, we need
4771 -- to call the special routine Unaligned_Valid, which makes
4772 -- the needed copy, being careful not to load the value into
4773 -- any floating-point register. The argument in this case is
4774 -- obj'Address (see Unaligned_Valid routine in Fat_Gen).
4776 if Is_Possibly_Unaligned_Object (Pref) then
4777 Expand_Fpt_Attribute
4778 (N, Pkg, Name_Unaligned_Valid,
4780 Make_Attribute_Reference (Loc,
4781 Prefix => Relocate_Node (Pref),
4782 Attribute_Name => Name_Address)));
4784 -- In the normal case where we are sure the object is
4785 -- aligned, we generate a call to Valid, and the argument in
4786 -- this case is obj'Unrestricted_Access (after converting
4787 -- obj to the right floating-point type).
4790 Expand_Fpt_Attribute
4791 (N, Pkg, Name_Valid,
4793 Make_Attribute_Reference (Loc,
4794 Prefix => Unchecked_Convert_To (Ftp, Pref),
4795 Attribute_Name => Name_Unrestricted_Access)));
4799 -- One more task, we still need a range check. Required
4800 -- only if we have a constraint, since the Valid routine
4801 -- catches infinities properly (infinities are never valid).
4803 -- The way we do the range check is simply to create the
4804 -- expression: Valid (N) and then Base_Type(Pref) in Typ.
4806 if not Subtypes_Statically_Match (Ptyp, Btyp) then
4809 Left_Opnd => Relocate_Node (N),
4812 Left_Opnd => Convert_To (Btyp, Pref),
4813 Right_Opnd => New_Occurrence_Of (Ptyp, Loc))));
4817 -- Enumeration type with holes
4819 -- For enumeration types with holes, the Pos value constructed by
4820 -- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a
4821 -- second argument of False returns minus one for an invalid value,
4822 -- and the non-negative pos value for a valid value, so the
4823 -- expansion of X'Valid is simply:
4825 -- type(X)'Pos (X) >= 0
4827 -- We can't quite generate it that way because of the requirement
4828 -- for the non-standard second argument of False in the resulting
4829 -- rep_to_pos call, so we have to explicitly create:
4831 -- _rep_to_pos (X, False) >= 0
4833 -- If we have an enumeration subtype, we also check that the
4834 -- value is in range:
4836 -- _rep_to_pos (X, False) >= 0
4838 -- (X >= type(X)'First and then type(X)'Last <= X)
4840 elsif Is_Enumeration_Type (Ptyp)
4841 and then Present (Enum_Pos_To_Rep (Base_Type (Ptyp)))
4846 Make_Function_Call (Loc,
4849 (TSS (Base_Type (Ptyp), TSS_Rep_To_Pos), Loc),
4850 Parameter_Associations => New_List (
4852 New_Occurrence_Of (Standard_False, Loc))),
4853 Right_Opnd => Make_Integer_Literal (Loc, 0));
4857 (Type_Low_Bound (Ptyp) /= Type_Low_Bound (Btyp)
4859 Type_High_Bound (Ptyp) /= Type_High_Bound (Btyp))
4861 -- The call to Make_Range_Test will create declarations
4862 -- that need a proper insertion point, but Pref is now
4863 -- attached to a node with no ancestor. Attach to tree
4864 -- even if it is to be rewritten below.
4866 Set_Parent (Tst, Parent (N));
4870 Left_Opnd => Make_Range_Test,
4876 -- Fortran convention booleans
4878 -- For the very special case of Fortran convention booleans, the
4879 -- value is always valid, since it is an integer with the semantics
4880 -- that non-zero is true, and any value is permissible.
4882 elsif Is_Boolean_Type (Ptyp)
4883 and then Convention (Ptyp) = Convention_Fortran
4885 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
4887 -- For biased representations, we will be doing an unchecked
4888 -- conversion without unbiasing the result. That means that the range
4889 -- test has to take this into account, and the proper form of the
4892 -- Btyp!(Pref) < Btyp!(Ptyp'Range_Length)
4894 elsif Has_Biased_Representation (Ptyp) then
4895 Btyp := RTE (RE_Unsigned_32);
4899 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
4901 Unchecked_Convert_To (Btyp,
4902 Make_Attribute_Reference (Loc,
4903 Prefix => New_Occurrence_Of (Ptyp, Loc),
4904 Attribute_Name => Name_Range_Length))));
4906 -- For all other scalar types, what we want logically is a
4909 -- X in type(X)'First .. type(X)'Last
4911 -- But that's precisely what won't work because of possible
4912 -- unwanted optimization (and indeed the basic motivation for
4913 -- the Valid attribute is exactly that this test does not work!)
4914 -- What will work is:
4916 -- Btyp!(X) >= Btyp!(type(X)'First)
4918 -- Btyp!(X) <= Btyp!(type(X)'Last)
4920 -- where Btyp is an integer type large enough to cover the full
4921 -- range of possible stored values (i.e. it is chosen on the basis
4922 -- of the size of the type, not the range of the values). We write
4923 -- this as two tests, rather than a range check, so that static
4924 -- evaluation will easily remove either or both of the checks if
4925 -- they can be -statically determined to be true (this happens
4926 -- when the type of X is static and the range extends to the full
4927 -- range of stored values).
4929 -- Unsigned types. Note: it is safe to consider only whether the
4930 -- subtype is unsigned, since we will in that case be doing all
4931 -- unsigned comparisons based on the subtype range. Since we use the
4932 -- actual subtype object size, this is appropriate.
4934 -- For example, if we have
4936 -- subtype x is integer range 1 .. 200;
4937 -- for x'Object_Size use 8;
4939 -- Now the base type is signed, but objects of this type are bits
4940 -- unsigned, and doing an unsigned test of the range 1 to 200 is
4941 -- correct, even though a value greater than 127 looks signed to a
4942 -- signed comparison.
4944 elsif Is_Unsigned_Type (Ptyp) then
4945 if Esize (Ptyp) <= 32 then
4946 Btyp := RTE (RE_Unsigned_32);
4948 Btyp := RTE (RE_Unsigned_64);
4951 Rewrite (N, Make_Range_Test);
4956 if Esize (Ptyp) <= Esize (Standard_Integer) then
4957 Btyp := Standard_Integer;
4959 Btyp := Universal_Integer;
4962 Rewrite (N, Make_Range_Test);
4965 Analyze_And_Resolve (N, Standard_Boolean);
4966 Validity_Checks_On := Save_Validity_Checks_On;
4973 -- Value attribute is handled in separate unti Exp_Imgv
4975 when Attribute_Value =>
4976 Exp_Imgv.Expand_Value_Attribute (N);
4982 -- The processing for Value_Size shares the processing for Size
4988 -- The processing for Version shares the processing for Body_Version
4994 -- Wide_Image attribute is handled in separate unit Exp_Imgv
4996 when Attribute_Wide_Image =>
4997 Exp_Imgv.Expand_Wide_Image_Attribute (N);
4999 ---------------------
5000 -- Wide_Wide_Image --
5001 ---------------------
5003 -- Wide_Wide_Image attribute is handled in separate unit Exp_Imgv
5005 when Attribute_Wide_Wide_Image =>
5006 Exp_Imgv.Expand_Wide_Wide_Image_Attribute (N);
5012 -- We expand typ'Wide_Value (X) into
5015 -- (Wide_String_To_String (X, Wide_Character_Encoding_Method))
5017 -- Wide_String_To_String is a runtime function that converts its wide
5018 -- string argument to String, converting any non-translatable characters
5019 -- into appropriate escape sequences. This preserves the required
5020 -- semantics of Wide_Value in all cases, and results in a very simple
5021 -- implementation approach.
5023 -- Note: for this approach to be fully standard compliant for the cases
5024 -- where typ is Wide_Character and Wide_Wide_Character, the encoding
5025 -- method must cover the entire character range (e.g. UTF-8). But that
5026 -- is a reasonable requirement when dealing with encoded character
5027 -- sequences. Presumably if one of the restrictive encoding mechanisms
5028 -- is in use such as Shift-JIS, then characters that cannot be
5029 -- represented using this encoding will not appear in any case.
5031 when Attribute_Wide_Value => Wide_Value :
5034 Make_Attribute_Reference (Loc,
5036 Attribute_Name => Name_Value,
5038 Expressions => New_List (
5039 Make_Function_Call (Loc,
5041 New_Reference_To (RTE (RE_Wide_String_To_String), Loc),
5043 Parameter_Associations => New_List (
5044 Relocate_Node (First (Exprs)),
5045 Make_Integer_Literal (Loc,
5046 Intval => Int (Wide_Character_Encoding_Method)))))));
5048 Analyze_And_Resolve (N, Typ);
5051 ---------------------
5052 -- Wide_Wide_Value --
5053 ---------------------
5055 -- We expand typ'Wide_Value_Value (X) into
5058 -- (Wide_Wide_String_To_String (X, Wide_Character_Encoding_Method))
5060 -- Wide_Wide_String_To_String is a runtime function that converts its
5061 -- wide string argument to String, converting any non-translatable
5062 -- characters into appropriate escape sequences. This preserves the
5063 -- required semantics of Wide_Wide_Value in all cases, and results in a
5064 -- very simple implementation approach.
5066 -- It's not quite right where typ = Wide_Wide_Character, because the
5067 -- encoding method may not cover the whole character type ???
5069 when Attribute_Wide_Wide_Value => Wide_Wide_Value :
5072 Make_Attribute_Reference (Loc,
5074 Attribute_Name => Name_Value,
5076 Expressions => New_List (
5077 Make_Function_Call (Loc,
5079 New_Reference_To (RTE (RE_Wide_Wide_String_To_String), Loc),
5081 Parameter_Associations => New_List (
5082 Relocate_Node (First (Exprs)),
5083 Make_Integer_Literal (Loc,
5084 Intval => Int (Wide_Character_Encoding_Method)))))));
5086 Analyze_And_Resolve (N, Typ);
5087 end Wide_Wide_Value;
5089 ---------------------
5090 -- Wide_Wide_Width --
5091 ---------------------
5093 -- Wide_Wide_Width attribute is handled in separate unit Exp_Imgv
5095 when Attribute_Wide_Wide_Width =>
5096 Exp_Imgv.Expand_Width_Attribute (N, Wide_Wide);
5102 -- Wide_Width attribute is handled in separate unit Exp_Imgv
5104 when Attribute_Wide_Width =>
5105 Exp_Imgv.Expand_Width_Attribute (N, Wide);
5111 -- Width attribute is handled in separate unit Exp_Imgv
5113 when Attribute_Width =>
5114 Exp_Imgv.Expand_Width_Attribute (N, Normal);
5120 when Attribute_Write => Write : declare
5121 P_Type : constant Entity_Id := Entity (Pref);
5122 U_Type : constant Entity_Id := Underlying_Type (P_Type);
5130 -- If no underlying type, we have an error that will be diagnosed
5131 -- elsewhere, so here we just completely ignore the expansion.
5137 -- The simple case, if there is a TSS for Write, just call it
5139 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Write);
5141 if Present (Pname) then
5145 -- If there is a Stream_Convert pragma, use it, we rewrite
5147 -- sourcetyp'Output (stream, Item)
5151 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
5153 -- where strmwrite is the given Write function that converts an
5154 -- argument of type sourcetyp or a type acctyp, from which it is
5155 -- derived to type strmtyp. The conversion to acttyp is required
5156 -- for the derived case.
5158 Prag := Get_Stream_Convert_Pragma (P_Type);
5160 if Present (Prag) then
5162 Next (Next (First (Pragma_Argument_Associations (Prag))));
5163 Wfunc := Entity (Expression (Arg3));
5166 Make_Attribute_Reference (Loc,
5167 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
5168 Attribute_Name => Name_Output,
5169 Expressions => New_List (
5170 Relocate_Node (First (Exprs)),
5171 Make_Function_Call (Loc,
5172 Name => New_Occurrence_Of (Wfunc, Loc),
5173 Parameter_Associations => New_List (
5174 OK_Convert_To (Etype (First_Formal (Wfunc)),
5175 Relocate_Node (Next (First (Exprs)))))))));
5180 -- For elementary types, we call the W_xxx routine directly
5182 elsif Is_Elementary_Type (U_Type) then
5183 Rewrite (N, Build_Elementary_Write_Call (N));
5189 elsif Is_Array_Type (U_Type) then
5190 Build_Array_Write_Procedure (N, U_Type, Decl, Pname);
5191 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
5193 -- Tagged type case, use the primitive Write function. Note that
5194 -- this will dispatch in the class-wide case which is what we want
5196 elsif Is_Tagged_Type (U_Type) then
5197 Pname := Find_Prim_Op (U_Type, TSS_Stream_Write);
5199 -- All other record type cases, including protected records.
5200 -- The latter only arise for expander generated code for
5201 -- handling shared passive partition access.
5205 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
5207 -- Ada 2005 (AI-216): Program_Error is raised when executing
5208 -- the default implementation of the Write attribute of an
5209 -- Unchecked_Union type. However, if the 'Write reference is
5210 -- within the generated Output stream procedure, Write outputs
5211 -- the components, and the default values of the discriminant
5212 -- are streamed by the Output procedure itself.
5214 if Is_Unchecked_Union (Base_Type (U_Type))
5215 and not Is_TSS (Current_Scope, TSS_Stream_Output)
5218 Make_Raise_Program_Error (Loc,
5219 Reason => PE_Unchecked_Union_Restriction));
5222 if Has_Discriminants (U_Type)
5224 (Discriminant_Default_Value (First_Discriminant (U_Type)))
5226 Build_Mutable_Record_Write_Procedure
5227 (Loc, Base_Type (U_Type), Decl, Pname);
5229 Build_Record_Write_Procedure
5230 (Loc, Base_Type (U_Type), Decl, Pname);
5233 Insert_Action (N, Decl);
5237 -- If we fall through, Pname is the procedure to be called
5239 Rewrite_Stream_Proc_Call (Pname);
5242 -- Component_Size is handled by the back end, unless the component size
5243 -- is known at compile time, which is always true in the packed array
5244 -- case. It is important that the packed array case is handled in the
5245 -- front end (see Eval_Attribute) since the back end would otherwise get
5246 -- confused by the equivalent packed array type.
5248 when Attribute_Component_Size =>
5251 -- The following attributes are handled by the back end (except that
5252 -- static cases have already been evaluated during semantic processing,
5253 -- but in any case the back end should not count on this). The one bit
5254 -- of special processing required is that these attributes typically
5255 -- generate conditionals in the code, so we need to check the relevant
5258 when Attribute_Max |
5260 Check_Restriction (No_Implicit_Conditionals, N);
5262 -- The following attributes are handled by the back end (except that
5263 -- static cases have already been evaluated during semantic processing,
5264 -- but in any case the back end should not count on this).
5266 -- The back end also handles the non-class-wide cases of Size
5268 when Attribute_Bit_Order |
5269 Attribute_Code_Address |
5270 Attribute_Definite |
5271 Attribute_Null_Parameter |
5272 Attribute_Passed_By_Reference |
5273 Attribute_Pool_Address =>
5276 -- The following attributes are also handled by the back end, but return
5277 -- a universal integer result, so may need a conversion for checking
5278 -- that the result is in range.
5280 when Attribute_Aft |
5282 Attribute_Max_Size_In_Storage_Elements
5284 Apply_Universal_Integer_Attribute_Checks (N);
5286 -- The following attributes should not appear at this stage, since they
5287 -- have already been handled by the analyzer (and properly rewritten
5288 -- with corresponding values or entities to represent the right values)
5290 when Attribute_Abort_Signal |
5291 Attribute_Address_Size |
5294 Attribute_Compiler_Version |
5295 Attribute_Default_Bit_Order |
5302 Attribute_Fast_Math |
5303 Attribute_Has_Access_Values |
5304 Attribute_Has_Discriminants |
5305 Attribute_Has_Tagged_Values |
5307 Attribute_Machine_Emax |
5308 Attribute_Machine_Emin |
5309 Attribute_Machine_Mantissa |
5310 Attribute_Machine_Overflows |
5311 Attribute_Machine_Radix |
5312 Attribute_Machine_Rounds |
5313 Attribute_Maximum_Alignment |
5314 Attribute_Model_Emin |
5315 Attribute_Model_Epsilon |
5316 Attribute_Model_Mantissa |
5317 Attribute_Model_Small |
5319 Attribute_Partition_ID |
5321 Attribute_Safe_Emax |
5322 Attribute_Safe_First |
5323 Attribute_Safe_Large |
5324 Attribute_Safe_Last |
5325 Attribute_Safe_Small |
5327 Attribute_Signed_Zeros |
5329 Attribute_Storage_Unit |
5330 Attribute_Stub_Type |
5331 Attribute_Target_Name |
5332 Attribute_Type_Class |
5333 Attribute_Unconstrained_Array |
5334 Attribute_Universal_Literal_String |
5335 Attribute_Wchar_T_Size |
5336 Attribute_Word_Size =>
5338 raise Program_Error;
5340 -- The Asm_Input and Asm_Output attributes are not expanded at this
5341 -- stage, but will be eliminated in the expansion of the Asm call, see
5342 -- Exp_Intr for details. So the back end will never see these either.
5344 when Attribute_Asm_Input |
5345 Attribute_Asm_Output =>
5352 when RE_Not_Available =>
5354 end Expand_N_Attribute_Reference;
5356 ----------------------
5357 -- Expand_Pred_Succ --
5358 ----------------------
5360 -- For typ'Pred (exp), we generate the check
5362 -- [constraint_error when exp = typ'Base'First]
5364 -- Similarly, for typ'Succ (exp), we generate the check
5366 -- [constraint_error when exp = typ'Base'Last]
5368 -- These checks are not generated for modular types, since the proper
5369 -- semantics for Succ and Pred on modular types is to wrap, not raise CE.
5371 procedure Expand_Pred_Succ (N : Node_Id) is
5372 Loc : constant Source_Ptr := Sloc (N);
5376 if Attribute_Name (N) = Name_Pred then
5383 Make_Raise_Constraint_Error (Loc,
5387 Duplicate_Subexpr_Move_Checks (First (Expressions (N))),
5389 Make_Attribute_Reference (Loc,
5391 New_Reference_To (Base_Type (Etype (Prefix (N))), Loc),
5392 Attribute_Name => Cnam)),
5393 Reason => CE_Overflow_Check_Failed));
5394 end Expand_Pred_Succ;
5400 procedure Find_Fat_Info
5402 Fat_Type : out Entity_Id;
5403 Fat_Pkg : out RE_Id)
5405 Btyp : constant Entity_Id := Base_Type (T);
5406 Rtyp : constant Entity_Id := Root_Type (T);
5407 Digs : constant Nat := UI_To_Int (Digits_Value (Btyp));
5410 -- If the base type is VAX float, then get appropriate VAX float type
5412 if Vax_Float (Btyp) then
5415 Fat_Type := RTE (RE_Fat_VAX_F);
5416 Fat_Pkg := RE_Attr_VAX_F_Float;
5419 Fat_Type := RTE (RE_Fat_VAX_D);
5420 Fat_Pkg := RE_Attr_VAX_D_Float;
5423 Fat_Type := RTE (RE_Fat_VAX_G);
5424 Fat_Pkg := RE_Attr_VAX_G_Float;
5427 raise Program_Error;
5430 -- If root type is VAX float, this is the case where the library has
5431 -- been recompiled in VAX float mode, and we have an IEEE float type.
5432 -- This is when we use the special IEEE Fat packages.
5434 elsif Vax_Float (Rtyp) then
5437 Fat_Type := RTE (RE_Fat_IEEE_Short);
5438 Fat_Pkg := RE_Attr_IEEE_Short;
5441 Fat_Type := RTE (RE_Fat_IEEE_Long);
5442 Fat_Pkg := RE_Attr_IEEE_Long;
5445 raise Program_Error;
5448 -- If neither the base type nor the root type is VAX_Float then VAX
5449 -- float is out of the picture, and we can just use the root type.
5454 if Fat_Type = Standard_Short_Float then
5455 Fat_Pkg := RE_Attr_Short_Float;
5457 elsif Fat_Type = Standard_Float then
5458 Fat_Pkg := RE_Attr_Float;
5460 elsif Fat_Type = Standard_Long_Float then
5461 Fat_Pkg := RE_Attr_Long_Float;
5463 elsif Fat_Type = Standard_Long_Long_Float then
5464 Fat_Pkg := RE_Attr_Long_Long_Float;
5466 -- Universal real (which is its own root type) is treated as being
5467 -- equivalent to Standard.Long_Long_Float, since it is defined to
5468 -- have the same precision as the longest Float type.
5470 elsif Fat_Type = Universal_Real then
5471 Fat_Type := Standard_Long_Long_Float;
5472 Fat_Pkg := RE_Attr_Long_Long_Float;
5475 raise Program_Error;
5480 ----------------------------
5481 -- Find_Stream_Subprogram --
5482 ----------------------------
5484 function Find_Stream_Subprogram
5486 Nam : TSS_Name_Type) return Entity_Id
5488 Base_Typ : constant Entity_Id := Base_Type (Typ);
5489 Ent : constant Entity_Id := TSS (Typ, Nam);
5492 if Present (Ent) then
5496 -- Stream attributes for strings are expanded into library calls. The
5497 -- following checks are disabled when the run-time is not available or
5498 -- when compiling predefined types due to bootstrap issues. As a result,
5499 -- the compiler will generate in-place stream routines for string types
5500 -- that appear in GNAT's library, but will generate calls via rtsfind
5501 -- to library routines for user code.
5502 -- ??? For now, disable this code for JVM, since this generates a
5503 -- VerifyError exception at run-time on e.g. c330001.
5504 -- This is disabled for AAMP, to avoid making dependences on files not
5505 -- supported in the AAMP library (such as s-fileio.adb).
5507 if VM_Target /= JVM_Target
5508 and then not AAMP_On_Target
5510 not Is_Predefined_File_Name (Unit_File_Name (Current_Sem_Unit))
5512 -- String as defined in package Ada
5514 if Base_Typ = Standard_String then
5515 if Restriction_Active (No_Stream_Optimizations) then
5516 if Nam = TSS_Stream_Input then
5517 return RTE (RE_String_Input);
5519 elsif Nam = TSS_Stream_Output then
5520 return RTE (RE_String_Output);
5522 elsif Nam = TSS_Stream_Read then
5523 return RTE (RE_String_Read);
5525 else pragma Assert (Nam = TSS_Stream_Write);
5526 return RTE (RE_String_Write);
5530 if Nam = TSS_Stream_Input then
5531 return RTE (RE_String_Input_Blk_IO);
5533 elsif Nam = TSS_Stream_Output then
5534 return RTE (RE_String_Output_Blk_IO);
5536 elsif Nam = TSS_Stream_Read then
5537 return RTE (RE_String_Read_Blk_IO);
5539 else pragma Assert (Nam = TSS_Stream_Write);
5540 return RTE (RE_String_Write_Blk_IO);
5544 -- Wide_String as defined in package Ada
5546 elsif Base_Typ = Standard_Wide_String then
5547 if Restriction_Active (No_Stream_Optimizations) then
5548 if Nam = TSS_Stream_Input then
5549 return RTE (RE_Wide_String_Input);
5551 elsif Nam = TSS_Stream_Output then
5552 return RTE (RE_Wide_String_Output);
5554 elsif Nam = TSS_Stream_Read then
5555 return RTE (RE_Wide_String_Read);
5557 else pragma Assert (Nam = TSS_Stream_Write);
5558 return RTE (RE_Wide_String_Write);
5562 if Nam = TSS_Stream_Input then
5563 return RTE (RE_Wide_String_Input_Blk_IO);
5565 elsif Nam = TSS_Stream_Output then
5566 return RTE (RE_Wide_String_Output_Blk_IO);
5568 elsif Nam = TSS_Stream_Read then
5569 return RTE (RE_Wide_String_Read_Blk_IO);
5571 else pragma Assert (Nam = TSS_Stream_Write);
5572 return RTE (RE_Wide_String_Write_Blk_IO);
5576 -- Wide_Wide_String as defined in package Ada
5578 elsif Base_Typ = Standard_Wide_Wide_String then
5579 if Restriction_Active (No_Stream_Optimizations) then
5580 if Nam = TSS_Stream_Input then
5581 return RTE (RE_Wide_Wide_String_Input);
5583 elsif Nam = TSS_Stream_Output then
5584 return RTE (RE_Wide_Wide_String_Output);
5586 elsif Nam = TSS_Stream_Read then
5587 return RTE (RE_Wide_Wide_String_Read);
5589 else pragma Assert (Nam = TSS_Stream_Write);
5590 return RTE (RE_Wide_Wide_String_Write);
5594 if Nam = TSS_Stream_Input then
5595 return RTE (RE_Wide_Wide_String_Input_Blk_IO);
5597 elsif Nam = TSS_Stream_Output then
5598 return RTE (RE_Wide_Wide_String_Output_Blk_IO);
5600 elsif Nam = TSS_Stream_Read then
5601 return RTE (RE_Wide_Wide_String_Read_Blk_IO);
5603 else pragma Assert (Nam = TSS_Stream_Write);
5604 return RTE (RE_Wide_Wide_String_Write_Blk_IO);
5610 if Is_Tagged_Type (Typ)
5611 and then Is_Derived_Type (Typ)
5613 return Find_Prim_Op (Typ, Nam);
5615 return Find_Inherited_TSS (Typ, Nam);
5617 end Find_Stream_Subprogram;
5619 -----------------------
5620 -- Get_Index_Subtype --
5621 -----------------------
5623 function Get_Index_Subtype (N : Node_Id) return Node_Id is
5624 P_Type : Entity_Id := Etype (Prefix (N));
5629 if Is_Access_Type (P_Type) then
5630 P_Type := Designated_Type (P_Type);
5633 if No (Expressions (N)) then
5636 J := UI_To_Int (Expr_Value (First (Expressions (N))));
5639 Indx := First_Index (P_Type);
5645 return Etype (Indx);
5646 end Get_Index_Subtype;
5648 -------------------------------
5649 -- Get_Stream_Convert_Pragma --
5650 -------------------------------
5652 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id is
5657 -- Note: we cannot use Get_Rep_Pragma here because of the peculiarity
5658 -- that a stream convert pragma for a tagged type is not inherited from
5659 -- its parent. Probably what is wrong here is that it is basically
5660 -- incorrect to consider a stream convert pragma to be a representation
5661 -- pragma at all ???
5663 N := First_Rep_Item (Implementation_Base_Type (T));
5664 while Present (N) loop
5665 if Nkind (N) = N_Pragma
5666 and then Pragma_Name (N) = Name_Stream_Convert
5668 -- For tagged types this pragma is not inherited, so we
5669 -- must verify that it is defined for the given type and
5673 Entity (Expression (First (Pragma_Argument_Associations (N))));
5675 if not Is_Tagged_Type (T)
5677 or else (Is_Private_Type (Typ) and then T = Full_View (Typ))
5687 end Get_Stream_Convert_Pragma;
5689 ---------------------------------
5690 -- Is_Constrained_Packed_Array --
5691 ---------------------------------
5693 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean is
5694 Arr : Entity_Id := Typ;
5697 if Is_Access_Type (Arr) then
5698 Arr := Designated_Type (Arr);
5701 return Is_Array_Type (Arr)
5702 and then Is_Constrained (Arr)
5703 and then Present (Packed_Array_Type (Arr));
5704 end Is_Constrained_Packed_Array;
5706 ----------------------------------------
5707 -- Is_Inline_Floating_Point_Attribute --
5708 ----------------------------------------
5710 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean is
5711 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
5714 if Nkind (Parent (N)) /= N_Type_Conversion
5715 or else not Is_Integer_Type (Etype (Parent (N)))
5720 -- Should also support 'Machine_Rounding and 'Unbiased_Rounding, but
5721 -- required back end support has not been implemented yet ???
5723 return Id = Attribute_Truncation;
5724 end Is_Inline_Floating_Point_Attribute;
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