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
658 -- the current instance of the type.
660 if Is_Protected_Self_Reference (Pref) then
661 Rewrite (Pref, Concurrent_Ref (Pref));
665 -- Remaining processing depends on specific attribute
673 when Attribute_Access |
674 Attribute_Unchecked_Access |
675 Attribute_Unrestricted_Access =>
677 Access_Cases : declare
678 Ref_Object : constant Node_Id := Get_Referenced_Object (Pref);
679 Btyp_DDT : Entity_Id;
681 function Enclosing_Object (N : Node_Id) return Node_Id;
682 -- If N denotes a compound name (selected component, indexed
683 -- component, or slice), returns the name of the outermost
684 -- such enclosing object. Otherwise returns N. If the object
685 -- is a renaming, then the renamed object is returned.
687 ----------------------
688 -- Enclosing_Object --
689 ----------------------
691 function Enclosing_Object (N : Node_Id) return Node_Id is
696 while Nkind_In (Obj_Name, N_Selected_Component,
700 Obj_Name := Prefix (Obj_Name);
703 return Get_Referenced_Object (Obj_Name);
704 end Enclosing_Object;
706 -- Local declarations
708 Enc_Object : constant Node_Id := Enclosing_Object (Ref_Object);
710 -- Start of processing for Access_Cases
713 Btyp_DDT := Designated_Type (Btyp);
715 -- Handle designated types that come from the limited view
717 if Ekind (Btyp_DDT) = E_Incomplete_Type
718 and then From_With_Type (Btyp_DDT)
719 and then Present (Non_Limited_View (Btyp_DDT))
721 Btyp_DDT := Non_Limited_View (Btyp_DDT);
723 elsif Is_Class_Wide_Type (Btyp_DDT)
724 and then Ekind (Etype (Btyp_DDT)) = E_Incomplete_Type
725 and then From_With_Type (Etype (Btyp_DDT))
726 and then Present (Non_Limited_View (Etype (Btyp_DDT)))
727 and then Present (Class_Wide_Type
728 (Non_Limited_View (Etype (Btyp_DDT))))
731 Class_Wide_Type (Non_Limited_View (Etype (Btyp_DDT)));
734 -- In order to improve the text of error messages, the designated
735 -- type of access-to-subprogram itypes is set by the semantics as
736 -- the associated subprogram entity (see sem_attr). Now we replace
737 -- such node with the proper E_Subprogram_Type itype.
739 if Id = Attribute_Unrestricted_Access
740 and then Is_Subprogram (Directly_Designated_Type (Typ))
742 -- The following conditions ensure that this special management
743 -- is done only for "Address!(Prim'Unrestricted_Access)" nodes.
744 -- At this stage other cases in which the designated type is
745 -- still a subprogram (instead of an E_Subprogram_Type) are
746 -- wrong because the semantics must have overridden the type of
747 -- the node with the type imposed by the context.
749 if Nkind (Parent (N)) = N_Unchecked_Type_Conversion
750 and then Etype (Parent (N)) = RTE (RE_Prim_Ptr)
752 Set_Etype (N, RTE (RE_Prim_Ptr));
756 Subp : constant Entity_Id :=
757 Directly_Designated_Type (Typ);
759 Extra : Entity_Id := Empty;
760 New_Formal : Entity_Id;
761 Old_Formal : Entity_Id := First_Formal (Subp);
762 Subp_Typ : Entity_Id;
765 Subp_Typ := Create_Itype (E_Subprogram_Type, N);
766 Set_Etype (Subp_Typ, Etype (Subp));
767 Set_Returns_By_Ref (Subp_Typ, Returns_By_Ref (Subp));
769 if Present (Old_Formal) then
770 New_Formal := New_Copy (Old_Formal);
771 Set_First_Entity (Subp_Typ, New_Formal);
774 Set_Scope (New_Formal, Subp_Typ);
775 Etyp := Etype (New_Formal);
777 -- Handle itypes. There is no need to duplicate
778 -- here the itypes associated with record types
779 -- (i.e the implicit full view of private types).
782 and then Ekind (Base_Type (Etyp)) /= E_Record_Type
784 Extra := New_Copy (Etyp);
785 Set_Parent (Extra, New_Formal);
786 Set_Etype (New_Formal, Extra);
787 Set_Scope (Extra, Subp_Typ);
791 Next_Formal (Old_Formal);
792 exit when No (Old_Formal);
794 Set_Next_Entity (New_Formal,
795 New_Copy (Old_Formal));
796 Next_Entity (New_Formal);
799 Set_Next_Entity (New_Formal, Empty);
800 Set_Last_Entity (Subp_Typ, Extra);
803 -- Now that the explicit formals have been duplicated,
804 -- any extra formals needed by the subprogram must be
807 if Present (Extra) then
808 Set_Extra_Formal (Extra, Empty);
811 Create_Extra_Formals (Subp_Typ);
812 Set_Directly_Designated_Type (Typ, Subp_Typ);
817 if Is_Access_Protected_Subprogram_Type (Btyp) then
818 Expand_Access_To_Protected_Op (N, Pref, Typ);
820 -- If prefix is a type name, this is a reference to the current
821 -- instance of the type, within its initialization procedure.
823 elsif Is_Entity_Name (Pref)
824 and then Is_Type (Entity (Pref))
831 -- If the current instance name denotes a task type, then
832 -- the access attribute is rewritten to be the name of the
833 -- "_task" parameter associated with the task type's task
834 -- procedure. An unchecked conversion is applied to ensure
835 -- a type match in cases of expander-generated calls (e.g.
838 if Is_Task_Type (Entity (Pref)) then
840 First_Entity (Get_Task_Body_Procedure (Entity (Pref)));
841 while Present (Formal) loop
842 exit when Chars (Formal) = Name_uTask;
843 Next_Entity (Formal);
846 pragma Assert (Present (Formal));
849 Unchecked_Convert_To (Typ,
850 New_Occurrence_Of (Formal, Loc)));
853 -- The expression must appear in a default expression,
854 -- (which in the initialization procedure is the
855 -- right-hand side of an assignment), and not in a
856 -- discriminant constraint.
860 while Present (Par) loop
861 exit when Nkind (Par) = N_Assignment_Statement;
863 if Nkind (Par) = N_Component_Declaration then
870 if Present (Par) then
872 Make_Attribute_Reference (Loc,
873 Prefix => Make_Identifier (Loc, Name_uInit),
874 Attribute_Name => Attribute_Name (N)));
876 Analyze_And_Resolve (N, Typ);
881 -- If the prefix of an Access attribute is a dereference of an
882 -- access parameter (or a renaming of such a dereference, or a
883 -- subcomponent of such a dereference) and the context is a
884 -- general access type (including the type of an object or
885 -- component with an access_definition, but not the anonymous
886 -- type of an access parameter or access discriminant), then
887 -- apply an accessibility check to the access parameter. We used
888 -- to rewrite the access parameter as a type conversion, but that
889 -- could only be done if the immediate prefix of the Access
890 -- attribute was the dereference, and didn't handle cases where
891 -- the attribute is applied to a subcomponent of the dereference,
892 -- since there's generally no available, appropriate access type
893 -- to convert to in that case. The attribute is passed as the
894 -- point to insert the check, because the access parameter may
895 -- come from a renaming, possibly in a different scope, and the
896 -- check must be associated with the attribute itself.
898 elsif Id = Attribute_Access
899 and then Nkind (Enc_Object) = N_Explicit_Dereference
900 and then Is_Entity_Name (Prefix (Enc_Object))
901 and then (Ekind (Btyp) = E_General_Access_Type
902 or else Is_Local_Anonymous_Access (Btyp))
903 and then Ekind (Entity (Prefix (Enc_Object))) in Formal_Kind
904 and then Ekind (Etype (Entity (Prefix (Enc_Object))))
905 = E_Anonymous_Access_Type
906 and then Present (Extra_Accessibility
907 (Entity (Prefix (Enc_Object))))
909 Apply_Accessibility_Check (Prefix (Enc_Object), Typ, N);
911 -- Ada 2005 (AI-251): If the designated type is an interface we
912 -- add an implicit conversion to force the displacement of the
913 -- pointer to reference the secondary dispatch table.
915 elsif Is_Interface (Btyp_DDT)
916 and then (Comes_From_Source (N)
917 or else Comes_From_Source (Ref_Object)
918 or else (Nkind (Ref_Object) in N_Has_Chars
919 and then Chars (Ref_Object) = Name_uInit))
921 if Nkind (Ref_Object) /= N_Explicit_Dereference then
923 -- No implicit conversion required if types match, or if
924 -- the prefix is the class_wide_type of the interface. In
925 -- either case passing an object of the interface type has
926 -- already set the pointer correctly.
928 if Btyp_DDT = Etype (Ref_Object)
929 or else (Is_Class_Wide_Type (Etype (Ref_Object))
931 Class_Wide_Type (Btyp_DDT) = Etype (Ref_Object))
937 Convert_To (Btyp_DDT,
938 New_Copy_Tree (Prefix (N))));
940 Analyze_And_Resolve (Prefix (N), Btyp_DDT);
943 -- When the object is an explicit dereference, convert the
944 -- dereference's prefix.
948 Obj_DDT : constant Entity_Id :=
950 (Directly_Designated_Type
951 (Etype (Prefix (Ref_Object))));
953 -- No implicit conversion required if designated types
956 if Obj_DDT /= Btyp_DDT
957 and then not (Is_Class_Wide_Type (Obj_DDT)
958 and then Etype (Obj_DDT) = Btyp_DDT)
962 New_Copy_Tree (Prefix (Ref_Object))));
963 Analyze_And_Resolve (N, Typ);
974 -- Transforms 'Adjacent into a call to the floating-point attribute
975 -- function Adjacent in Fat_xxx (where xxx is the root type)
977 when Attribute_Adjacent =>
978 Expand_Fpt_Attribute_RR (N);
984 when Attribute_Address => Address : declare
985 Task_Proc : Entity_Id;
988 -- If the prefix is a task or a task type, the useful address is that
989 -- of the procedure for the task body, i.e. the actual program unit.
990 -- We replace the original entity with that of the procedure.
992 if Is_Entity_Name (Pref)
993 and then Is_Task_Type (Entity (Pref))
995 Task_Proc := Next_Entity (Root_Type (Ptyp));
997 while Present (Task_Proc) loop
998 exit when Ekind (Task_Proc) = E_Procedure
999 and then Etype (First_Formal (Task_Proc)) =
1000 Corresponding_Record_Type (Ptyp);
1001 Next_Entity (Task_Proc);
1004 if Present (Task_Proc) then
1005 Set_Entity (Pref, Task_Proc);
1006 Set_Etype (Pref, Etype (Task_Proc));
1009 -- Similarly, the address of a protected operation is the address
1010 -- of the corresponding protected body, regardless of the protected
1011 -- object from which it is selected.
1013 elsif Nkind (Pref) = N_Selected_Component
1014 and then Is_Subprogram (Entity (Selector_Name (Pref)))
1015 and then Is_Protected_Type (Scope (Entity (Selector_Name (Pref))))
1019 External_Subprogram (Entity (Selector_Name (Pref))), Loc));
1021 elsif Nkind (Pref) = N_Explicit_Dereference
1022 and then Ekind (Ptyp) = E_Subprogram_Type
1023 and then Convention (Ptyp) = Convention_Protected
1025 -- The prefix is be a dereference of an access_to_protected_
1026 -- subprogram. The desired address is the second component of
1027 -- the record that represents the access.
1030 Addr : constant Entity_Id := Etype (N);
1031 Ptr : constant Node_Id := Prefix (Pref);
1032 T : constant Entity_Id :=
1033 Equivalent_Type (Base_Type (Etype (Ptr)));
1037 Unchecked_Convert_To (Addr,
1038 Make_Selected_Component (Loc,
1039 Prefix => Unchecked_Convert_To (T, Ptr),
1040 Selector_Name => New_Occurrence_Of (
1041 Next_Entity (First_Entity (T)), Loc))));
1043 Analyze_And_Resolve (N, Addr);
1046 -- Ada 2005 (AI-251): Class-wide interface objects are always
1047 -- "displaced" to reference the tag associated with the interface
1048 -- type. In order to obtain the real address of such objects we
1049 -- generate a call to a run-time subprogram that returns the base
1050 -- address of the object.
1052 -- This processing is not needed in the VM case, where dispatching
1053 -- issues are taken care of by the virtual machine.
1055 elsif Is_Class_Wide_Type (Ptyp)
1056 and then Is_Interface (Ptyp)
1057 and then Tagged_Type_Expansion
1058 and then not (Nkind (Pref) in N_Has_Entity
1059 and then Is_Subprogram (Entity (Pref)))
1062 Make_Function_Call (Loc,
1063 Name => New_Reference_To (RTE (RE_Base_Address), Loc),
1064 Parameter_Associations => New_List (
1065 Relocate_Node (N))));
1070 -- Deal with packed array reference, other cases are handled by
1073 if Involves_Packed_Array_Reference (Pref) then
1074 Expand_Packed_Address_Reference (N);
1082 when Attribute_Alignment => Alignment : declare
1086 -- For class-wide types, X'Class'Alignment is transformed into a
1087 -- direct reference to the Alignment of the class type, so that the
1088 -- back end does not have to deal with the X'Class'Alignment
1091 if Is_Entity_Name (Pref)
1092 and then Is_Class_Wide_Type (Entity (Pref))
1094 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
1097 -- For x'Alignment applied to an object of a class wide type,
1098 -- transform X'Alignment into a call to the predefined primitive
1099 -- operation _Alignment applied to X.
1101 elsif Is_Class_Wide_Type (Ptyp) then
1103 -- No need to do anything else compiling under restriction
1104 -- No_Dispatching_Calls. During the semantic analysis we
1105 -- already notified such violation.
1107 if Restriction_Active (No_Dispatching_Calls) then
1112 Make_Function_Call (Loc,
1113 Name => New_Reference_To
1114 (Find_Prim_Op (Ptyp, Name_uAlignment), Loc),
1115 Parameter_Associations => New_List (Pref));
1117 if Typ /= Standard_Integer then
1119 -- The context is a specific integer type with which the
1120 -- original attribute was compatible. The function has a
1121 -- specific type as well, so to preserve the compatibility
1122 -- we must convert explicitly.
1124 New_Node := Convert_To (Typ, New_Node);
1127 Rewrite (N, New_Node);
1128 Analyze_And_Resolve (N, Typ);
1131 -- For all other cases, we just have to deal with the case of
1132 -- the fact that the result can be universal.
1135 Apply_Universal_Integer_Attribute_Checks (N);
1143 when Attribute_AST_Entry => AST_Entry : declare
1148 Entry_Ref : Node_Id;
1149 -- The reference to the entry or entry family
1152 -- The index expression for an entry family reference, or
1153 -- the Empty if Entry_Ref references a simple entry.
1156 if Nkind (Pref) = N_Indexed_Component then
1157 Entry_Ref := Prefix (Pref);
1158 Index := First (Expressions (Pref));
1164 -- Get expression for Task_Id and the entry entity
1166 if Nkind (Entry_Ref) = N_Selected_Component then
1168 Make_Attribute_Reference (Loc,
1169 Attribute_Name => Name_Identity,
1170 Prefix => Prefix (Entry_Ref));
1172 Ttyp := Etype (Prefix (Entry_Ref));
1173 Eent := Entity (Selector_Name (Entry_Ref));
1177 Make_Function_Call (Loc,
1178 Name => New_Occurrence_Of (RTE (RE_Current_Task), Loc));
1180 Eent := Entity (Entry_Ref);
1182 -- We have to find the enclosing task to get the task type
1183 -- There must be one, since we already validated this earlier
1185 Ttyp := Current_Scope;
1186 while not Is_Task_Type (Ttyp) loop
1187 Ttyp := Scope (Ttyp);
1191 -- Now rewrite the attribute with a call to Create_AST_Handler
1194 Make_Function_Call (Loc,
1195 Name => New_Occurrence_Of (RTE (RE_Create_AST_Handler), Loc),
1196 Parameter_Associations => New_List (
1198 Entry_Index_Expression (Loc, Eent, Index, Ttyp))));
1200 Analyze_And_Resolve (N, RTE (RE_AST_Handler));
1207 -- We compute this if a component clause was present, otherwise we leave
1208 -- the computation up to the back end, since we don't know what layout
1211 -- Note that the attribute can apply to a naked record component
1212 -- in generated code (i.e. the prefix is an identifier that
1213 -- references the component or discriminant entity).
1215 when Attribute_Bit_Position => Bit_Position :
1220 if Nkind (Pref) = N_Identifier then
1221 CE := Entity (Pref);
1223 CE := Entity (Selector_Name (Pref));
1226 if Known_Static_Component_Bit_Offset (CE) then
1228 Make_Integer_Literal (Loc,
1229 Intval => Component_Bit_Offset (CE)));
1230 Analyze_And_Resolve (N, Typ);
1233 Apply_Universal_Integer_Attribute_Checks (N);
1241 -- A reference to P'Body_Version or P'Version is expanded to
1244 -- pragma Import (C, Vnn, "uuuuT");
1246 -- Get_Version_String (Vnn)
1248 -- where uuuu is the unit name (dots replaced by double underscore)
1249 -- and T is B for the cases of Body_Version, or Version applied to a
1250 -- subprogram acting as its own spec, and S for Version applied to a
1251 -- subprogram spec or package. This sequence of code references the
1252 -- the unsigned constant created in the main program by the binder.
1254 -- A special exception occurs for Standard, where the string
1255 -- returned is a copy of the library string in gnatvsn.ads.
1257 when Attribute_Body_Version | Attribute_Version => Version : declare
1258 E : constant Entity_Id :=
1259 Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
1264 -- If not library unit, get to containing library unit
1266 Pent := Entity (Pref);
1267 while Pent /= Standard_Standard
1268 and then Scope (Pent) /= Standard_Standard
1269 and then not Is_Child_Unit (Pent)
1271 Pent := Scope (Pent);
1274 -- Special case Standard and Standard.ASCII
1276 if Pent = Standard_Standard or else Pent = Standard_ASCII then
1278 Make_String_Literal (Loc,
1279 Strval => Verbose_Library_Version));
1284 -- Build required string constant
1286 Get_Name_String (Get_Unit_Name (Pent));
1289 for J in 1 .. Name_Len - 2 loop
1290 if Name_Buffer (J) = '.' then
1291 Store_String_Chars ("__");
1293 Store_String_Char (Get_Char_Code (Name_Buffer (J)));
1297 -- Case of subprogram acting as its own spec, always use body
1299 if Nkind (Declaration_Node (Pent)) in N_Subprogram_Specification
1300 and then Nkind (Parent (Declaration_Node (Pent))) =
1302 and then Acts_As_Spec (Parent (Declaration_Node (Pent)))
1304 Store_String_Chars ("B");
1306 -- Case of no body present, always use spec
1308 elsif not Unit_Requires_Body (Pent) then
1309 Store_String_Chars ("S");
1311 -- Otherwise use B for Body_Version, S for spec
1313 elsif Id = Attribute_Body_Version then
1314 Store_String_Chars ("B");
1316 Store_String_Chars ("S");
1320 Lib.Version_Referenced (S);
1322 -- Insert the object declaration
1324 Insert_Actions (N, New_List (
1325 Make_Object_Declaration (Loc,
1326 Defining_Identifier => E,
1327 Object_Definition =>
1328 New_Occurrence_Of (RTE (RE_Unsigned), Loc))));
1330 -- Set entity as imported with correct external name
1332 Set_Is_Imported (E);
1333 Set_Interface_Name (E, Make_String_Literal (Loc, S));
1335 -- Set entity as internal to ensure proper Sprint output of its
1336 -- implicit importation.
1338 Set_Is_Internal (E);
1340 -- And now rewrite original reference
1343 Make_Function_Call (Loc,
1344 Name => New_Reference_To (RTE (RE_Get_Version_String), Loc),
1345 Parameter_Associations => New_List (
1346 New_Occurrence_Of (E, Loc))));
1349 Analyze_And_Resolve (N, RTE (RE_Version_String));
1356 -- Transforms 'Ceiling into a call to the floating-point attribute
1357 -- function Ceiling in Fat_xxx (where xxx is the root type)
1359 when Attribute_Ceiling =>
1360 Expand_Fpt_Attribute_R (N);
1366 -- Transforms 'Callable attribute into a call to the Callable function
1368 when Attribute_Callable => Callable :
1370 -- We have an object of a task interface class-wide type as a prefix
1371 -- to Callable. Generate:
1372 -- callable (Task_Id (Pref._disp_get_task_id));
1374 if Ada_Version >= Ada_05
1375 and then Ekind (Ptyp) = E_Class_Wide_Type
1376 and then Is_Interface (Ptyp)
1377 and then Is_Task_Interface (Ptyp)
1380 Make_Function_Call (Loc,
1382 New_Reference_To (RTE (RE_Callable), Loc),
1383 Parameter_Associations => New_List (
1384 Make_Unchecked_Type_Conversion (Loc,
1386 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
1388 Make_Selected_Component (Loc,
1390 New_Copy_Tree (Pref),
1392 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
1396 Build_Call_With_Task (Pref, RTE (RE_Callable)));
1399 Analyze_And_Resolve (N, Standard_Boolean);
1406 -- Transforms 'Caller attribute into a call to either the
1407 -- Task_Entry_Caller or the Protected_Entry_Caller function.
1409 when Attribute_Caller => Caller : declare
1410 Id_Kind : constant Entity_Id := RTE (RO_AT_Task_Id);
1411 Ent : constant Entity_Id := Entity (Pref);
1412 Conctype : constant Entity_Id := Scope (Ent);
1413 Nest_Depth : Integer := 0;
1420 if Is_Protected_Type (Conctype) then
1421 case Corresponding_Runtime_Package (Conctype) is
1422 when System_Tasking_Protected_Objects_Entries =>
1425 (RTE (RE_Protected_Entry_Caller), Loc);
1427 when System_Tasking_Protected_Objects_Single_Entry =>
1430 (RTE (RE_Protected_Single_Entry_Caller), Loc);
1433 raise Program_Error;
1437 Unchecked_Convert_To (Id_Kind,
1438 Make_Function_Call (Loc,
1440 Parameter_Associations => New_List (
1442 (Find_Protection_Object (Current_Scope), Loc)))));
1447 -- Determine the nesting depth of the E'Caller attribute, that
1448 -- is, how many accept statements are nested within the accept
1449 -- statement for E at the point of E'Caller. The runtime uses
1450 -- this depth to find the specified entry call.
1452 for J in reverse 0 .. Scope_Stack.Last loop
1453 S := Scope_Stack.Table (J).Entity;
1455 -- We should not reach the scope of the entry, as it should
1456 -- already have been checked in Sem_Attr that this attribute
1457 -- reference is within a matching accept statement.
1459 pragma Assert (S /= Conctype);
1464 elsif Is_Entry (S) then
1465 Nest_Depth := Nest_Depth + 1;
1470 Unchecked_Convert_To (Id_Kind,
1471 Make_Function_Call (Loc,
1473 New_Reference_To (RTE (RE_Task_Entry_Caller), Loc),
1474 Parameter_Associations => New_List (
1475 Make_Integer_Literal (Loc,
1476 Intval => Int (Nest_Depth))))));
1479 Analyze_And_Resolve (N, Id_Kind);
1486 -- Transforms 'Compose into a call to the floating-point attribute
1487 -- function Compose in Fat_xxx (where xxx is the root type)
1489 -- Note: we strictly should have special code here to deal with the
1490 -- case of absurdly negative arguments (less than Integer'First)
1491 -- which will return a (signed) zero value, but it hardly seems
1492 -- worth the effort. Absurdly large positive arguments will raise
1493 -- constraint error which is fine.
1495 when Attribute_Compose =>
1496 Expand_Fpt_Attribute_RI (N);
1502 when Attribute_Constrained => Constrained : declare
1503 Formal_Ent : constant Entity_Id := Param_Entity (Pref);
1505 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean;
1506 -- Ada 2005 (AI-363): Returns True if the object name Obj denotes a
1507 -- view of an aliased object whose subtype is constrained.
1509 ---------------------------------
1510 -- Is_Constrained_Aliased_View --
1511 ---------------------------------
1513 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean is
1517 if Is_Entity_Name (Obj) then
1520 if Present (Renamed_Object (E)) then
1521 return Is_Constrained_Aliased_View (Renamed_Object (E));
1523 return Is_Aliased (E) and then Is_Constrained (Etype (E));
1527 return Is_Aliased_View (Obj)
1529 (Is_Constrained (Etype (Obj))
1530 or else (Nkind (Obj) = N_Explicit_Dereference
1532 not Has_Constrained_Partial_View
1533 (Base_Type (Etype (Obj)))));
1535 end Is_Constrained_Aliased_View;
1537 -- Start of processing for Constrained
1540 -- Reference to a parameter where the value is passed as an extra
1541 -- actual, corresponding to the extra formal referenced by the
1542 -- Extra_Constrained field of the corresponding formal. If this
1543 -- is an entry in-parameter, it is replaced by a constant renaming
1544 -- for which Extra_Constrained is never created.
1546 if Present (Formal_Ent)
1547 and then Ekind (Formal_Ent) /= E_Constant
1548 and then Present (Extra_Constrained (Formal_Ent))
1552 (Extra_Constrained (Formal_Ent), Sloc (N)));
1554 -- For variables with a Extra_Constrained field, we use the
1555 -- corresponding entity.
1557 elsif Nkind (Pref) = N_Identifier
1558 and then Ekind (Entity (Pref)) = E_Variable
1559 and then Present (Extra_Constrained (Entity (Pref)))
1563 (Extra_Constrained (Entity (Pref)), Sloc (N)));
1565 -- For all other entity names, we can tell at compile time
1567 elsif Is_Entity_Name (Pref) then
1569 Ent : constant Entity_Id := Entity (Pref);
1573 -- (RM J.4) obsolescent cases
1575 if Is_Type (Ent) then
1579 if Is_Private_Type (Ent) then
1580 Res := not Has_Discriminants (Ent)
1581 or else Is_Constrained (Ent);
1583 -- It not a private type, must be a generic actual type
1584 -- that corresponded to a private type. We know that this
1585 -- correspondence holds, since otherwise the reference
1586 -- within the generic template would have been illegal.
1589 if Is_Composite_Type (Underlying_Type (Ent)) then
1590 Res := Is_Constrained (Ent);
1596 -- If the prefix is not a variable or is aliased, then
1597 -- definitely true; if it's a formal parameter without an
1598 -- associated extra formal, then treat it as constrained.
1600 -- Ada 2005 (AI-363): An aliased prefix must be known to be
1601 -- constrained in order to set the attribute to True.
1603 elsif not Is_Variable (Pref)
1604 or else Present (Formal_Ent)
1605 or else (Ada_Version < Ada_05
1606 and then Is_Aliased_View (Pref))
1607 or else (Ada_Version >= Ada_05
1608 and then Is_Constrained_Aliased_View (Pref))
1612 -- Variable case, look at type to see if it is constrained.
1613 -- Note that the one case where this is not accurate (the
1614 -- procedure formal case), has been handled above.
1616 -- We use the Underlying_Type here (and below) in case the
1617 -- type is private without discriminants, but the full type
1618 -- has discriminants. This case is illegal, but we generate it
1619 -- internally for passing to the Extra_Constrained parameter.
1622 Res := Is_Constrained (Underlying_Type (Etype (Ent)));
1626 New_Reference_To (Boolean_Literals (Res), Loc));
1629 -- Prefix is not an entity name. These are also cases where we can
1630 -- always tell at compile time by looking at the form and type of the
1631 -- prefix. If an explicit dereference of an object with constrained
1632 -- partial view, this is unconstrained (Ada 2005 AI-363).
1638 not Is_Variable (Pref)
1640 (Nkind (Pref) = N_Explicit_Dereference
1642 not Has_Constrained_Partial_View (Base_Type (Ptyp)))
1643 or else Is_Constrained (Underlying_Type (Ptyp))),
1647 Analyze_And_Resolve (N, Standard_Boolean);
1654 -- Transforms 'Copy_Sign into a call to the floating-point attribute
1655 -- function Copy_Sign in Fat_xxx (where xxx is the root type)
1657 when Attribute_Copy_Sign =>
1658 Expand_Fpt_Attribute_RR (N);
1664 -- Transforms 'Count attribute into a call to the Count function
1666 when Attribute_Count => Count : declare
1668 Conctyp : Entity_Id;
1670 Entry_Id : Entity_Id;
1675 -- If the prefix is a member of an entry family, retrieve both
1676 -- entry name and index. For a simple entry there is no index.
1678 if Nkind (Pref) = N_Indexed_Component then
1679 Entnam := Prefix (Pref);
1680 Index := First (Expressions (Pref));
1686 Entry_Id := Entity (Entnam);
1688 -- Find the concurrent type in which this attribute is referenced
1689 -- (there had better be one).
1691 Conctyp := Current_Scope;
1692 while not Is_Concurrent_Type (Conctyp) loop
1693 Conctyp := Scope (Conctyp);
1698 if Is_Protected_Type (Conctyp) then
1699 case Corresponding_Runtime_Package (Conctyp) is
1700 when System_Tasking_Protected_Objects_Entries =>
1701 Name := New_Reference_To (RTE (RE_Protected_Count), Loc);
1704 Make_Function_Call (Loc,
1706 Parameter_Associations => New_List (
1708 (Find_Protection_Object (Current_Scope), Loc),
1709 Entry_Index_Expression
1710 (Loc, Entry_Id, Index, Scope (Entry_Id))));
1712 when System_Tasking_Protected_Objects_Single_Entry =>
1714 New_Reference_To (RTE (RE_Protected_Count_Entry), Loc);
1717 Make_Function_Call (Loc,
1719 Parameter_Associations => New_List (
1721 (Find_Protection_Object (Current_Scope), Loc)));
1724 raise Program_Error;
1731 Make_Function_Call (Loc,
1732 Name => New_Reference_To (RTE (RE_Task_Count), Loc),
1733 Parameter_Associations => New_List (
1734 Entry_Index_Expression (Loc,
1735 Entry_Id, Index, Scope (Entry_Id))));
1738 -- The call returns type Natural but the context is universal integer
1739 -- so any integer type is allowed. The attribute was already resolved
1740 -- so its Etype is the required result type. If the base type of the
1741 -- context type is other than Standard.Integer we put in a conversion
1742 -- to the required type. This can be a normal typed conversion since
1743 -- both input and output types of the conversion are integer types
1745 if Base_Type (Typ) /= Base_Type (Standard_Integer) then
1746 Rewrite (N, Convert_To (Typ, Call));
1751 Analyze_And_Resolve (N, Typ);
1758 -- This processing is shared by Elab_Spec
1760 -- What we do is to insert the following declarations
1763 -- pragma Import (C, enn, "name___elabb/s");
1765 -- and then the Elab_Body/Spec attribute is replaced by a reference
1766 -- to this defining identifier.
1768 when Attribute_Elab_Body |
1769 Attribute_Elab_Spec =>
1772 Ent : constant Entity_Id :=
1773 Make_Defining_Identifier (Loc,
1774 New_Internal_Name ('E'));
1778 procedure Make_Elab_String (Nod : Node_Id);
1779 -- Given Nod, an identifier, or a selected component, put the
1780 -- image into the current string literal, with double underline
1781 -- between components.
1783 ----------------------
1784 -- Make_Elab_String --
1785 ----------------------
1787 procedure Make_Elab_String (Nod : Node_Id) is
1789 if Nkind (Nod) = N_Selected_Component then
1790 Make_Elab_String (Prefix (Nod));
1794 Store_String_Char ('$');
1796 Store_String_Char ('.');
1798 Store_String_Char ('_');
1799 Store_String_Char ('_');
1802 Get_Name_String (Chars (Selector_Name (Nod)));
1805 pragma Assert (Nkind (Nod) = N_Identifier);
1806 Get_Name_String (Chars (Nod));
1809 Store_String_Chars (Name_Buffer (1 .. Name_Len));
1810 end Make_Elab_String;
1812 -- Start of processing for Elab_Body/Elab_Spec
1815 -- First we need to prepare the string literal for the name of
1816 -- the elaboration routine to be referenced.
1819 Make_Elab_String (Pref);
1821 if VM_Target = No_VM then
1822 Store_String_Chars ("___elab");
1823 Lang := Make_Identifier (Loc, Name_C);
1825 Store_String_Chars ("._elab");
1826 Lang := Make_Identifier (Loc, Name_Ada);
1829 if Id = Attribute_Elab_Body then
1830 Store_String_Char ('b');
1832 Store_String_Char ('s');
1837 Insert_Actions (N, New_List (
1838 Make_Subprogram_Declaration (Loc,
1840 Make_Procedure_Specification (Loc,
1841 Defining_Unit_Name => Ent)),
1844 Chars => Name_Import,
1845 Pragma_Argument_Associations => New_List (
1846 Make_Pragma_Argument_Association (Loc,
1847 Expression => Lang),
1849 Make_Pragma_Argument_Association (Loc,
1851 Make_Identifier (Loc, Chars (Ent))),
1853 Make_Pragma_Argument_Association (Loc,
1855 Make_String_Literal (Loc, Str))))));
1857 Set_Entity (N, Ent);
1858 Rewrite (N, New_Occurrence_Of (Ent, Loc));
1865 -- Elaborated is always True for preelaborated units, predefined units,
1866 -- pure units and units which have Elaborate_Body pragmas. These units
1867 -- have no elaboration entity.
1869 -- Note: The Elaborated attribute is never passed to the back end
1871 when Attribute_Elaborated => Elaborated : declare
1872 Ent : constant Entity_Id := Entity (Pref);
1875 if Present (Elaboration_Entity (Ent)) then
1877 New_Occurrence_Of (Elaboration_Entity (Ent), Loc));
1879 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
1887 when Attribute_Enum_Rep => Enum_Rep :
1889 -- X'Enum_Rep (Y) expands to
1893 -- This is simply a direct conversion from the enumeration type to
1894 -- the target integer type, which is treated by the back end as a
1895 -- normal integer conversion, treating the enumeration type as an
1896 -- integer, which is exactly what we want! We set Conversion_OK to
1897 -- make sure that the analyzer does not complain about what otherwise
1898 -- might be an illegal conversion.
1900 if Is_Non_Empty_List (Exprs) then
1902 OK_Convert_To (Typ, Relocate_Node (First (Exprs))));
1904 -- X'Enum_Rep where X is an enumeration literal is replaced by
1905 -- the literal value.
1907 elsif Ekind (Entity (Pref)) = E_Enumeration_Literal then
1909 Make_Integer_Literal (Loc, Enumeration_Rep (Entity (Pref))));
1911 -- If this is a renaming of a literal, recover the representation
1914 elsif Ekind (Entity (Pref)) = E_Constant
1915 and then Present (Renamed_Object (Entity (Pref)))
1917 Ekind (Entity (Renamed_Object (Entity (Pref))))
1918 = E_Enumeration_Literal
1921 Make_Integer_Literal (Loc,
1922 Enumeration_Rep (Entity (Renamed_Object (Entity (Pref))))));
1924 -- X'Enum_Rep where X is an object does a direct unchecked conversion
1925 -- of the object value, as described for the type case above.
1929 OK_Convert_To (Typ, Relocate_Node (Pref)));
1933 Analyze_And_Resolve (N, Typ);
1940 when Attribute_Enum_Val => Enum_Val : declare
1942 Btyp : constant Entity_Id := Base_Type (Ptyp);
1945 -- X'Enum_Val (Y) expands to
1947 -- [constraint_error when _rep_to_pos (Y, False) = -1, msg]
1950 Expr := Unchecked_Convert_To (Ptyp, First (Exprs));
1953 Make_Raise_Constraint_Error (Loc,
1957 Make_Function_Call (Loc,
1959 New_Reference_To (TSS (Btyp, TSS_Rep_To_Pos), Loc),
1960 Parameter_Associations => New_List (
1961 Relocate_Node (Duplicate_Subexpr (Expr)),
1962 New_Occurrence_Of (Standard_False, Loc))),
1964 Right_Opnd => Make_Integer_Literal (Loc, -1)),
1965 Reason => CE_Range_Check_Failed));
1968 Analyze_And_Resolve (N, Ptyp);
1975 -- Transforms 'Exponent into a call to the floating-point attribute
1976 -- function Exponent in Fat_xxx (where xxx is the root type)
1978 when Attribute_Exponent =>
1979 Expand_Fpt_Attribute_R (N);
1985 -- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag)
1987 when Attribute_External_Tag => External_Tag :
1990 Make_Function_Call (Loc,
1991 Name => New_Reference_To (RTE (RE_External_Tag), Loc),
1992 Parameter_Associations => New_List (
1993 Make_Attribute_Reference (Loc,
1994 Attribute_Name => Name_Tag,
1995 Prefix => Prefix (N)))));
1997 Analyze_And_Resolve (N, Standard_String);
2004 when Attribute_First =>
2006 -- If the prefix type is a constrained packed array type which
2007 -- already has a Packed_Array_Type representation defined, then
2008 -- replace this attribute with a direct reference to 'First of the
2009 -- appropriate index subtype (since otherwise the back end will try
2010 -- to give us the value of 'First for this implementation type).
2012 if Is_Constrained_Packed_Array (Ptyp) then
2014 Make_Attribute_Reference (Loc,
2015 Attribute_Name => Name_First,
2016 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
2017 Analyze_And_Resolve (N, Typ);
2019 elsif Is_Access_Type (Ptyp) then
2020 Apply_Access_Check (N);
2027 -- Compute this if component clause was present, otherwise we leave the
2028 -- computation to be completed in the back-end, since we don't know what
2029 -- layout will be chosen.
2031 when Attribute_First_Bit => First_Bit : declare
2032 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2035 if Known_Static_Component_Bit_Offset (CE) then
2037 Make_Integer_Literal (Loc,
2038 Component_Bit_Offset (CE) mod System_Storage_Unit));
2040 Analyze_And_Resolve (N, Typ);
2043 Apply_Universal_Integer_Attribute_Checks (N);
2053 -- fixtype'Fixed_Value (integer-value)
2057 -- fixtype(integer-value)
2059 -- We do all the required analysis of the conversion here, because we do
2060 -- not want this to go through the fixed-point conversion circuits. Note
2061 -- that the back end always treats fixed-point as equivalent to the
2062 -- corresponding integer type anyway.
2064 when Attribute_Fixed_Value => Fixed_Value :
2067 Make_Type_Conversion (Loc,
2068 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2069 Expression => Relocate_Node (First (Exprs))));
2070 Set_Etype (N, Entity (Pref));
2073 -- Note: it might appear that a properly analyzed unchecked conversion
2074 -- would be just fine here, but that's not the case, since the full
2075 -- range checks performed by the following call are critical!
2077 Apply_Type_Conversion_Checks (N);
2084 -- Transforms 'Floor into a call to the floating-point attribute
2085 -- function Floor in Fat_xxx (where xxx is the root type)
2087 when Attribute_Floor =>
2088 Expand_Fpt_Attribute_R (N);
2094 -- For the fixed-point type Typ:
2100 -- Result_Type (System.Fore (Universal_Real (Type'First)),
2101 -- Universal_Real (Type'Last))
2103 -- Note that we know that the type is a non-static subtype, or Fore
2104 -- would have itself been computed dynamically in Eval_Attribute.
2106 when Attribute_Fore => Fore : begin
2109 Make_Function_Call (Loc,
2110 Name => New_Reference_To (RTE (RE_Fore), Loc),
2112 Parameter_Associations => New_List (
2113 Convert_To (Universal_Real,
2114 Make_Attribute_Reference (Loc,
2115 Prefix => New_Reference_To (Ptyp, Loc),
2116 Attribute_Name => Name_First)),
2118 Convert_To (Universal_Real,
2119 Make_Attribute_Reference (Loc,
2120 Prefix => New_Reference_To (Ptyp, Loc),
2121 Attribute_Name => Name_Last))))));
2123 Analyze_And_Resolve (N, Typ);
2130 -- Transforms 'Fraction into a call to the floating-point attribute
2131 -- function Fraction in Fat_xxx (where xxx is the root type)
2133 when Attribute_Fraction =>
2134 Expand_Fpt_Attribute_R (N);
2140 when Attribute_From_Any => From_Any : declare
2141 P_Type : constant Entity_Id := Etype (Pref);
2142 Decls : constant List_Id := New_List;
2145 Build_From_Any_Call (P_Type,
2146 Relocate_Node (First (Exprs)),
2148 Insert_Actions (N, Decls);
2149 Analyze_And_Resolve (N, P_Type);
2156 -- For an exception returns a reference to the exception data:
2157 -- Exception_Id!(Prefix'Reference)
2159 -- For a task it returns a reference to the _task_id component of
2160 -- corresponding record:
2162 -- taskV!(Prefix)._Task_Id, converted to the type Task_Id defined
2164 -- in Ada.Task_Identification
2166 when Attribute_Identity => Identity : declare
2167 Id_Kind : Entity_Id;
2170 if Ptyp = Standard_Exception_Type then
2171 Id_Kind := RTE (RE_Exception_Id);
2173 if Present (Renamed_Object (Entity (Pref))) then
2174 Set_Entity (Pref, Renamed_Object (Entity (Pref)));
2178 Unchecked_Convert_To (Id_Kind, Make_Reference (Loc, Pref)));
2180 Id_Kind := RTE (RO_AT_Task_Id);
2182 -- If the prefix is a task interface, the Task_Id is obtained
2183 -- dynamically through a dispatching call, as for other task
2184 -- attributes applied to interfaces.
2186 if Ada_Version >= Ada_05
2187 and then Ekind (Ptyp) = E_Class_Wide_Type
2188 and then Is_Interface (Ptyp)
2189 and then Is_Task_Interface (Ptyp)
2192 Unchecked_Convert_To (Id_Kind,
2193 Make_Selected_Component (Loc,
2195 New_Copy_Tree (Pref),
2197 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))));
2201 Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref)));
2205 Analyze_And_Resolve (N, Id_Kind);
2212 -- Image attribute is handled in separate unit Exp_Imgv
2214 when Attribute_Image =>
2215 Exp_Imgv.Expand_Image_Attribute (N);
2221 -- X'Img is expanded to typ'Image (X), where typ is the type of X
2223 when Attribute_Img => Img :
2226 Make_Attribute_Reference (Loc,
2227 Prefix => New_Reference_To (Ptyp, Loc),
2228 Attribute_Name => Name_Image,
2229 Expressions => New_List (Relocate_Node (Pref))));
2231 Analyze_And_Resolve (N, Standard_String);
2238 when Attribute_Input => Input : declare
2239 P_Type : constant Entity_Id := Entity (Pref);
2240 B_Type : constant Entity_Id := Base_Type (P_Type);
2241 U_Type : constant Entity_Id := Underlying_Type (P_Type);
2242 Strm : constant Node_Id := First (Exprs);
2250 Cntrl : Node_Id := Empty;
2251 -- Value for controlling argument in call. Always Empty except in
2252 -- the dispatching (class-wide type) case, where it is a reference
2253 -- to the dummy object initialized to the right internal tag.
2255 procedure Freeze_Stream_Subprogram (F : Entity_Id);
2256 -- The expansion of the attribute reference may generate a call to
2257 -- a user-defined stream subprogram that is frozen by the call. This
2258 -- can lead to access-before-elaboration problem if the reference
2259 -- appears in an object declaration and the subprogram body has not
2260 -- been seen. The freezing of the subprogram requires special code
2261 -- because it appears in an expanded context where expressions do
2262 -- not freeze their constituents.
2264 ------------------------------
2265 -- Freeze_Stream_Subprogram --
2266 ------------------------------
2268 procedure Freeze_Stream_Subprogram (F : Entity_Id) is
2269 Decl : constant Node_Id := Unit_Declaration_Node (F);
2273 -- If this is user-defined subprogram, the corresponding
2274 -- stream function appears as a renaming-as-body, and the
2275 -- user subprogram must be retrieved by tree traversal.
2278 and then Nkind (Decl) = N_Subprogram_Declaration
2279 and then Present (Corresponding_Body (Decl))
2281 Bod := Corresponding_Body (Decl);
2283 if Nkind (Unit_Declaration_Node (Bod)) =
2284 N_Subprogram_Renaming_Declaration
2286 Set_Is_Frozen (Entity (Name (Unit_Declaration_Node (Bod))));
2289 end Freeze_Stream_Subprogram;
2291 -- Start of processing for Input
2294 -- If no underlying type, we have an error that will be diagnosed
2295 -- elsewhere, so here we just completely ignore the expansion.
2301 -- If there is a TSS for Input, just call it
2303 Fname := Find_Stream_Subprogram (P_Type, TSS_Stream_Input);
2305 if Present (Fname) then
2309 -- If there is a Stream_Convert pragma, use it, we rewrite
2311 -- sourcetyp'Input (stream)
2315 -- sourcetyp (streamread (strmtyp'Input (stream)));
2317 -- where streamread is the given Read function that converts an
2318 -- argument of type strmtyp to type sourcetyp or a type from which
2319 -- it is derived (extra conversion required for the derived case).
2321 Prag := Get_Stream_Convert_Pragma (P_Type);
2323 if Present (Prag) then
2324 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
2325 Rfunc := Entity (Expression (Arg2));
2329 Make_Function_Call (Loc,
2330 Name => New_Occurrence_Of (Rfunc, Loc),
2331 Parameter_Associations => New_List (
2332 Make_Attribute_Reference (Loc,
2335 (Etype (First_Formal (Rfunc)), Loc),
2336 Attribute_Name => Name_Input,
2337 Expressions => Exprs)))));
2339 Analyze_And_Resolve (N, B_Type);
2344 elsif Is_Elementary_Type (U_Type) then
2346 -- A special case arises if we have a defined _Read routine,
2347 -- since in this case we are required to call this routine.
2349 if Present (TSS (Base_Type (U_Type), TSS_Stream_Read)) then
2350 Build_Record_Or_Elementary_Input_Function
2351 (Loc, U_Type, Decl, Fname);
2352 Insert_Action (N, Decl);
2354 -- For normal cases, we call the I_xxx routine directly
2357 Rewrite (N, Build_Elementary_Input_Call (N));
2358 Analyze_And_Resolve (N, P_Type);
2364 elsif Is_Array_Type (U_Type) then
2365 Build_Array_Input_Function (Loc, U_Type, Decl, Fname);
2366 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
2368 -- Dispatching case with class-wide type
2370 elsif Is_Class_Wide_Type (P_Type) then
2372 -- No need to do anything else compiling under restriction
2373 -- No_Dispatching_Calls. During the semantic analysis we
2374 -- already notified such violation.
2376 if Restriction_Active (No_Dispatching_Calls) then
2381 Rtyp : constant Entity_Id := Root_Type (P_Type);
2386 -- Read the internal tag (RM 13.13.2(34)) and use it to
2387 -- initialize a dummy tag object:
2389 -- Dnn : Ada.Tags.Tag
2390 -- := Descendant_Tag (String'Input (Strm), P_Type);
2392 -- This dummy object is used only to provide a controlling
2393 -- argument for the eventual _Input call. Descendant_Tag is
2394 -- called rather than Internal_Tag to ensure that we have a
2395 -- tag for a type that is descended from the prefix type and
2396 -- declared at the same accessibility level (the exception
2397 -- Tag_Error will be raised otherwise). The level check is
2398 -- required for Ada 2005 because tagged types can be
2399 -- extended in nested scopes (AI-344).
2402 Make_Defining_Identifier (Loc,
2403 Chars => New_Internal_Name ('D'));
2406 Make_Object_Declaration (Loc,
2407 Defining_Identifier => Dnn,
2408 Object_Definition =>
2409 New_Occurrence_Of (RTE (RE_Tag), Loc),
2411 Make_Function_Call (Loc,
2413 New_Occurrence_Of (RTE (RE_Descendant_Tag), Loc),
2414 Parameter_Associations => New_List (
2415 Make_Attribute_Reference (Loc,
2417 New_Occurrence_Of (Standard_String, Loc),
2418 Attribute_Name => Name_Input,
2419 Expressions => New_List (
2421 (Duplicate_Subexpr (Strm)))),
2422 Make_Attribute_Reference (Loc,
2423 Prefix => New_Reference_To (P_Type, Loc),
2424 Attribute_Name => Name_Tag))));
2426 Insert_Action (N, Decl);
2428 -- Now we need to get the entity for the call, and construct
2429 -- a function call node, where we preset a reference to Dnn
2430 -- as the controlling argument (doing an unchecked convert
2431 -- to the class-wide tagged type to make it look like a real
2434 Fname := Find_Prim_Op (Rtyp, TSS_Stream_Input);
2435 Cntrl := Unchecked_Convert_To (P_Type,
2436 New_Occurrence_Of (Dnn, Loc));
2437 Set_Etype (Cntrl, P_Type);
2438 Set_Parent (Cntrl, N);
2441 -- For tagged types, use the primitive Input function
2443 elsif Is_Tagged_Type (U_Type) then
2444 Fname := Find_Prim_Op (U_Type, TSS_Stream_Input);
2446 -- All other record type cases, including protected records. The
2447 -- latter only arise for expander generated code for handling
2448 -- shared passive partition access.
2452 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
2454 -- Ada 2005 (AI-216): Program_Error is raised executing default
2455 -- implementation of the Input attribute of an unchecked union
2456 -- type if the type lacks default discriminant values.
2458 if Is_Unchecked_Union (Base_Type (U_Type))
2459 and then No (Discriminant_Constraint (U_Type))
2462 Make_Raise_Program_Error (Loc,
2463 Reason => PE_Unchecked_Union_Restriction));
2468 Build_Record_Or_Elementary_Input_Function
2469 (Loc, Base_Type (U_Type), Decl, Fname);
2470 Insert_Action (N, Decl);
2472 if Nkind (Parent (N)) = N_Object_Declaration
2473 and then Is_Record_Type (U_Type)
2475 -- The stream function may contain calls to user-defined
2476 -- Read procedures for individual components.
2483 Comp := First_Component (U_Type);
2484 while Present (Comp) loop
2486 Find_Stream_Subprogram
2487 (Etype (Comp), TSS_Stream_Read);
2489 if Present (Func) then
2490 Freeze_Stream_Subprogram (Func);
2493 Next_Component (Comp);
2500 -- If we fall through, Fname is the function to be called. The result
2501 -- is obtained by calling the appropriate function, then converting
2502 -- the result. The conversion does a subtype check.
2505 Make_Function_Call (Loc,
2506 Name => New_Occurrence_Of (Fname, Loc),
2507 Parameter_Associations => New_List (
2508 Relocate_Node (Strm)));
2510 Set_Controlling_Argument (Call, Cntrl);
2511 Rewrite (N, Unchecked_Convert_To (P_Type, Call));
2512 Analyze_And_Resolve (N, P_Type);
2514 if Nkind (Parent (N)) = N_Object_Declaration then
2515 Freeze_Stream_Subprogram (Fname);
2525 -- inttype'Fixed_Value (fixed-value)
2529 -- inttype(integer-value))
2531 -- we do all the required analysis of the conversion here, because we do
2532 -- not want this to go through the fixed-point conversion circuits. Note
2533 -- that the back end always treats fixed-point as equivalent to the
2534 -- corresponding integer type anyway.
2536 when Attribute_Integer_Value => Integer_Value :
2539 Make_Type_Conversion (Loc,
2540 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2541 Expression => Relocate_Node (First (Exprs))));
2542 Set_Etype (N, Entity (Pref));
2545 -- Note: it might appear that a properly analyzed unchecked conversion
2546 -- would be just fine here, but that's not the case, since the full
2547 -- range checks performed by the following call are critical!
2549 Apply_Type_Conversion_Checks (N);
2556 when Attribute_Invalid_Value =>
2557 Rewrite (N, Get_Simple_Init_Val (Ptyp, N));
2563 when Attribute_Last =>
2565 -- If the prefix type is a constrained packed array type which
2566 -- already has a Packed_Array_Type representation defined, then
2567 -- replace this attribute with a direct reference to 'Last of the
2568 -- appropriate index subtype (since otherwise the back end will try
2569 -- to give us the value of 'Last for this implementation type).
2571 if Is_Constrained_Packed_Array (Ptyp) then
2573 Make_Attribute_Reference (Loc,
2574 Attribute_Name => Name_Last,
2575 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
2576 Analyze_And_Resolve (N, Typ);
2578 elsif Is_Access_Type (Ptyp) then
2579 Apply_Access_Check (N);
2586 -- We compute this if a component clause was present, otherwise we leave
2587 -- the computation up to the back end, since we don't know what layout
2590 when Attribute_Last_Bit => Last_Bit : declare
2591 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2594 if Known_Static_Component_Bit_Offset (CE)
2595 and then Known_Static_Esize (CE)
2598 Make_Integer_Literal (Loc,
2599 Intval => (Component_Bit_Offset (CE) mod System_Storage_Unit)
2602 Analyze_And_Resolve (N, Typ);
2605 Apply_Universal_Integer_Attribute_Checks (N);
2613 -- Transforms 'Leading_Part into a call to the floating-point attribute
2614 -- function Leading_Part in Fat_xxx (where xxx is the root type)
2616 -- Note: strictly, we should generate special case code to deal with
2617 -- absurdly large positive arguments (greater than Integer'Last), which
2618 -- result in returning the first argument unchanged, but it hardly seems
2619 -- worth the effort. We raise constraint error for absurdly negative
2620 -- arguments which is fine.
2622 when Attribute_Leading_Part =>
2623 Expand_Fpt_Attribute_RI (N);
2629 when Attribute_Length => declare
2634 -- Processing for packed array types
2636 if Is_Array_Type (Ptyp) and then Is_Packed (Ptyp) then
2637 Ityp := Get_Index_Subtype (N);
2639 -- If the index type, Ityp, is an enumeration type with holes,
2640 -- then we calculate X'Length explicitly using
2643 -- (0, Ityp'Pos (X'Last (N)) -
2644 -- Ityp'Pos (X'First (N)) + 1);
2646 -- Since the bounds in the template are the representation values
2647 -- and the back end would get the wrong value.
2649 if Is_Enumeration_Type (Ityp)
2650 and then Present (Enum_Pos_To_Rep (Base_Type (Ityp)))
2655 Xnum := Expr_Value (First (Expressions (N)));
2659 Make_Attribute_Reference (Loc,
2660 Prefix => New_Occurrence_Of (Typ, Loc),
2661 Attribute_Name => Name_Max,
2662 Expressions => New_List
2663 (Make_Integer_Literal (Loc, 0),
2667 Make_Op_Subtract (Loc,
2669 Make_Attribute_Reference (Loc,
2670 Prefix => New_Occurrence_Of (Ityp, Loc),
2671 Attribute_Name => Name_Pos,
2673 Expressions => New_List (
2674 Make_Attribute_Reference (Loc,
2675 Prefix => Duplicate_Subexpr (Pref),
2676 Attribute_Name => Name_Last,
2677 Expressions => New_List (
2678 Make_Integer_Literal (Loc, Xnum))))),
2681 Make_Attribute_Reference (Loc,
2682 Prefix => New_Occurrence_Of (Ityp, Loc),
2683 Attribute_Name => Name_Pos,
2685 Expressions => New_List (
2686 Make_Attribute_Reference (Loc,
2688 Duplicate_Subexpr_No_Checks (Pref),
2689 Attribute_Name => Name_First,
2690 Expressions => New_List (
2691 Make_Integer_Literal (Loc, Xnum)))))),
2693 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
2695 Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
2698 -- If the prefix type is a constrained packed array type which
2699 -- already has a Packed_Array_Type representation defined, then
2700 -- replace this attribute with a direct reference to 'Range_Length
2701 -- of the appropriate index subtype (since otherwise the back end
2702 -- will try to give us the value of 'Length for this
2703 -- implementation type).
2705 elsif Is_Constrained (Ptyp) then
2707 Make_Attribute_Reference (Loc,
2708 Attribute_Name => Name_Range_Length,
2709 Prefix => New_Reference_To (Ityp, Loc)));
2710 Analyze_And_Resolve (N, Typ);
2715 elsif Is_Access_Type (Ptyp) then
2716 Apply_Access_Check (N);
2718 -- If the designated type is a packed array type, then we convert
2719 -- the reference to:
2722 -- xtyp'Pos (Pref'Last (Expr)) -
2723 -- xtyp'Pos (Pref'First (Expr)));
2725 -- This is a bit complex, but it is the easiest thing to do that
2726 -- works in all cases including enum types with holes xtyp here
2727 -- is the appropriate index type.
2730 Dtyp : constant Entity_Id := Designated_Type (Ptyp);
2734 if Is_Array_Type (Dtyp) and then Is_Packed (Dtyp) then
2735 Xtyp := Get_Index_Subtype (N);
2738 Make_Attribute_Reference (Loc,
2739 Prefix => New_Occurrence_Of (Typ, Loc),
2740 Attribute_Name => Name_Max,
2741 Expressions => New_List (
2742 Make_Integer_Literal (Loc, 0),
2745 Make_Integer_Literal (Loc, 1),
2746 Make_Op_Subtract (Loc,
2748 Make_Attribute_Reference (Loc,
2749 Prefix => New_Occurrence_Of (Xtyp, Loc),
2750 Attribute_Name => Name_Pos,
2751 Expressions => New_List (
2752 Make_Attribute_Reference (Loc,
2753 Prefix => Duplicate_Subexpr (Pref),
2754 Attribute_Name => Name_Last,
2756 New_Copy_List (Exprs)))),
2759 Make_Attribute_Reference (Loc,
2760 Prefix => New_Occurrence_Of (Xtyp, Loc),
2761 Attribute_Name => Name_Pos,
2762 Expressions => New_List (
2763 Make_Attribute_Reference (Loc,
2765 Duplicate_Subexpr_No_Checks (Pref),
2766 Attribute_Name => Name_First,
2768 New_Copy_List (Exprs)))))))));
2770 Analyze_And_Resolve (N, Typ);
2774 -- Otherwise leave it to the back end
2777 Apply_Universal_Integer_Attribute_Checks (N);
2785 -- Transforms 'Machine into a call to the floating-point attribute
2786 -- function Machine in Fat_xxx (where xxx is the root type)
2788 when Attribute_Machine =>
2789 Expand_Fpt_Attribute_R (N);
2791 ----------------------
2792 -- Machine_Rounding --
2793 ----------------------
2795 -- Transforms 'Machine_Rounding into a call to the floating-point
2796 -- attribute function Machine_Rounding in Fat_xxx (where xxx is the root
2797 -- type). Expansion is avoided for cases the back end can handle
2800 when Attribute_Machine_Rounding =>
2801 if not Is_Inline_Floating_Point_Attribute (N) then
2802 Expand_Fpt_Attribute_R (N);
2809 -- Machine_Size is equivalent to Object_Size, so transform it into
2810 -- Object_Size and that way the back end never sees Machine_Size.
2812 when Attribute_Machine_Size =>
2814 Make_Attribute_Reference (Loc,
2815 Prefix => Prefix (N),
2816 Attribute_Name => Name_Object_Size));
2818 Analyze_And_Resolve (N, Typ);
2824 -- The only case that can get this far is the dynamic case of the old
2825 -- Ada 83 Mantissa attribute for the fixed-point case. For this case,
2832 -- ityp (System.Mantissa.Mantissa_Value
2833 -- (Integer'Integer_Value (typ'First),
2834 -- Integer'Integer_Value (typ'Last)));
2836 when Attribute_Mantissa => Mantissa : begin
2839 Make_Function_Call (Loc,
2840 Name => New_Occurrence_Of (RTE (RE_Mantissa_Value), Loc),
2842 Parameter_Associations => New_List (
2844 Make_Attribute_Reference (Loc,
2845 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2846 Attribute_Name => Name_Integer_Value,
2847 Expressions => New_List (
2849 Make_Attribute_Reference (Loc,
2850 Prefix => New_Occurrence_Of (Ptyp, Loc),
2851 Attribute_Name => Name_First))),
2853 Make_Attribute_Reference (Loc,
2854 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2855 Attribute_Name => Name_Integer_Value,
2856 Expressions => New_List (
2858 Make_Attribute_Reference (Loc,
2859 Prefix => New_Occurrence_Of (Ptyp, Loc),
2860 Attribute_Name => Name_Last)))))));
2862 Analyze_And_Resolve (N, Typ);
2865 --------------------
2866 -- Mechanism_Code --
2867 --------------------
2869 when Attribute_Mechanism_Code =>
2871 -- We must replace the prefix in the renamed case
2873 if Is_Entity_Name (Pref)
2874 and then Present (Alias (Entity (Pref)))
2876 Set_Renamed_Subprogram (Pref, Alias (Entity (Pref)));
2883 when Attribute_Mod => Mod_Case : declare
2884 Arg : constant Node_Id := Relocate_Node (First (Exprs));
2885 Hi : constant Node_Id := Type_High_Bound (Etype (Arg));
2886 Modv : constant Uint := Modulus (Btyp);
2890 -- This is not so simple. The issue is what type to use for the
2891 -- computation of the modular value.
2893 -- The easy case is when the modulus value is within the bounds
2894 -- of the signed integer type of the argument. In this case we can
2895 -- just do the computation in that signed integer type, and then
2896 -- do an ordinary conversion to the target type.
2898 if Modv <= Expr_Value (Hi) then
2903 Right_Opnd => Make_Integer_Literal (Loc, Modv))));
2905 -- Here we know that the modulus is larger than type'Last of the
2906 -- integer type. There are two cases to consider:
2908 -- a) The integer value is non-negative. In this case, it is
2909 -- returned as the result (since it is less than the modulus).
2911 -- b) The integer value is negative. In this case, we know that the
2912 -- result is modulus + value, where the value might be as small as
2913 -- -modulus. The trouble is what type do we use to do the subtract.
2914 -- No type will do, since modulus can be as big as 2**64, and no
2915 -- integer type accommodates this value. Let's do bit of algebra
2918 -- = modulus - (-value)
2919 -- = (modulus - 1) - (-value - 1)
2921 -- Now modulus - 1 is certainly in range of the modular type.
2922 -- -value is in the range 1 .. modulus, so -value -1 is in the
2923 -- range 0 .. modulus-1 which is in range of the modular type.
2924 -- Furthermore, (-value - 1) can be expressed as -(value + 1)
2925 -- which we can compute using the integer base type.
2927 -- Once this is done we analyze the conditional expression without
2928 -- range checks, because we know everything is in range, and we
2929 -- want to prevent spurious warnings on either branch.
2933 Make_Conditional_Expression (Loc,
2934 Expressions => New_List (
2936 Left_Opnd => Duplicate_Subexpr (Arg),
2937 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2940 Duplicate_Subexpr_No_Checks (Arg)),
2942 Make_Op_Subtract (Loc,
2944 Make_Integer_Literal (Loc,
2945 Intval => Modv - 1),
2951 Left_Opnd => Duplicate_Subexpr_No_Checks (Arg),
2953 Make_Integer_Literal (Loc,
2954 Intval => 1))))))));
2958 Analyze_And_Resolve (N, Btyp, Suppress => All_Checks);
2965 -- Transforms 'Model into a call to the floating-point attribute
2966 -- function Model in Fat_xxx (where xxx is the root type)
2968 when Attribute_Model =>
2969 Expand_Fpt_Attribute_R (N);
2975 -- The processing for Object_Size shares the processing for Size
2981 when Attribute_Old => Old : declare
2982 Tnn : constant Entity_Id :=
2983 Make_Defining_Identifier (Loc,
2984 Chars => New_Internal_Name ('T'));
2989 -- Find the nearest subprogram body, ignoring _Preconditions
2993 Subp := Parent (Subp);
2994 exit when Nkind (Subp) = N_Subprogram_Body
2995 and then Chars (Defining_Entity (Subp)) /= Name_uPostconditions;
2998 -- Insert the assignment at the start of the declarations
3001 Make_Object_Declaration (Loc,
3002 Defining_Identifier => Tnn,
3003 Constant_Present => True,
3004 Object_Definition => New_Occurrence_Of (Etype (N), Loc),
3005 Expression => Pref);
3007 if Is_Empty_List (Declarations (Subp)) then
3008 Set_Declarations (Subp, New_List (Asn_Stm));
3011 Insert_Action (First (Declarations (Subp)), Asn_Stm);
3014 Rewrite (N, New_Occurrence_Of (Tnn, Loc));
3021 when Attribute_Output => Output : declare
3022 P_Type : constant Entity_Id := Entity (Pref);
3023 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3031 -- If no underlying type, we have an error that will be diagnosed
3032 -- elsewhere, so here we just completely ignore the expansion.
3038 -- If TSS for Output is present, just call it
3040 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Output);
3042 if Present (Pname) then
3046 -- If there is a Stream_Convert pragma, use it, we rewrite
3048 -- sourcetyp'Output (stream, Item)
3052 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
3054 -- where strmwrite is the given Write function that converts an
3055 -- argument of type sourcetyp or a type acctyp, from which it is
3056 -- derived to type strmtyp. The conversion to acttyp is required
3057 -- for the derived case.
3059 Prag := Get_Stream_Convert_Pragma (P_Type);
3061 if Present (Prag) then
3063 Next (Next (First (Pragma_Argument_Associations (Prag))));
3064 Wfunc := Entity (Expression (Arg3));
3067 Make_Attribute_Reference (Loc,
3068 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
3069 Attribute_Name => Name_Output,
3070 Expressions => New_List (
3071 Relocate_Node (First (Exprs)),
3072 Make_Function_Call (Loc,
3073 Name => New_Occurrence_Of (Wfunc, Loc),
3074 Parameter_Associations => New_List (
3075 OK_Convert_To (Etype (First_Formal (Wfunc)),
3076 Relocate_Node (Next (First (Exprs)))))))));
3081 -- For elementary types, we call the W_xxx routine directly.
3082 -- Note that the effect of Write and Output is identical for
3083 -- the case of an elementary type, since there are no
3084 -- discriminants or bounds.
3086 elsif Is_Elementary_Type (U_Type) then
3088 -- A special case arises if we have a defined _Write routine,
3089 -- since in this case we are required to call this routine.
3091 if Present (TSS (Base_Type (U_Type), TSS_Stream_Write)) then
3092 Build_Record_Or_Elementary_Output_Procedure
3093 (Loc, U_Type, Decl, Pname);
3094 Insert_Action (N, Decl);
3096 -- For normal cases, we call the W_xxx routine directly
3099 Rewrite (N, Build_Elementary_Write_Call (N));
3106 elsif Is_Array_Type (U_Type) then
3107 Build_Array_Output_Procedure (Loc, U_Type, Decl, Pname);
3108 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3110 -- Class-wide case, first output external tag, then dispatch
3111 -- to the appropriate primitive Output function (RM 13.13.2(31)).
3113 elsif Is_Class_Wide_Type (P_Type) then
3115 -- No need to do anything else compiling under restriction
3116 -- No_Dispatching_Calls. During the semantic analysis we
3117 -- already notified such violation.
3119 if Restriction_Active (No_Dispatching_Calls) then
3124 Strm : constant Node_Id := First (Exprs);
3125 Item : constant Node_Id := Next (Strm);
3128 -- Ada 2005 (AI-344): Check that the accessibility level
3129 -- of the type of the output object is not deeper than
3130 -- that of the attribute's prefix type.
3132 -- if Get_Access_Level (Item'Tag)
3133 -- /= Get_Access_Level (P_Type'Tag)
3138 -- String'Output (Strm, External_Tag (Item'Tag));
3140 -- We cannot figure out a practical way to implement this
3141 -- accessibility check on virtual machines, so we omit it.
3143 if Ada_Version >= Ada_05
3144 and then Tagged_Type_Expansion
3147 Make_Implicit_If_Statement (N,
3151 Build_Get_Access_Level (Loc,
3152 Make_Attribute_Reference (Loc,
3155 Duplicate_Subexpr (Item,
3157 Attribute_Name => Name_Tag)),
3160 Make_Integer_Literal (Loc,
3161 Type_Access_Level (P_Type))),
3164 New_List (Make_Raise_Statement (Loc,
3166 RTE (RE_Tag_Error), Loc)))));
3170 Make_Attribute_Reference (Loc,
3171 Prefix => New_Occurrence_Of (Standard_String, Loc),
3172 Attribute_Name => Name_Output,
3173 Expressions => New_List (
3174 Relocate_Node (Duplicate_Subexpr (Strm)),
3175 Make_Function_Call (Loc,
3177 New_Occurrence_Of (RTE (RE_External_Tag), Loc),
3178 Parameter_Associations => New_List (
3179 Make_Attribute_Reference (Loc,
3182 (Duplicate_Subexpr (Item, Name_Req => True)),
3183 Attribute_Name => Name_Tag))))));
3186 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
3188 -- Tagged type case, use the primitive Output function
3190 elsif Is_Tagged_Type (U_Type) then
3191 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
3193 -- All other record type cases, including protected records.
3194 -- The latter only arise for expander generated code for
3195 -- handling shared passive partition access.
3199 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3201 -- Ada 2005 (AI-216): Program_Error is raised when executing
3202 -- the default implementation of the Output attribute of an
3203 -- unchecked union type if the type lacks default discriminant
3206 if Is_Unchecked_Union (Base_Type (U_Type))
3207 and then No (Discriminant_Constraint (U_Type))
3210 Make_Raise_Program_Error (Loc,
3211 Reason => PE_Unchecked_Union_Restriction));
3216 Build_Record_Or_Elementary_Output_Procedure
3217 (Loc, Base_Type (U_Type), Decl, Pname);
3218 Insert_Action (N, Decl);
3222 -- If we fall through, Pname is the name of the procedure to call
3224 Rewrite_Stream_Proc_Call (Pname);
3231 -- For enumeration types with a standard representation, Pos is
3232 -- handled by the back end.
3234 -- For enumeration types, with a non-standard representation we
3235 -- generate a call to the _Rep_To_Pos function created when the
3236 -- type was frozen. The call has the form
3238 -- _rep_to_pos (expr, flag)
3240 -- The parameter flag is True if range checks are enabled, causing
3241 -- Program_Error to be raised if the expression has an invalid
3242 -- representation, and False if range checks are suppressed.
3244 -- For integer types, Pos is equivalent to a simple integer
3245 -- conversion and we rewrite it as such
3247 when Attribute_Pos => Pos :
3249 Etyp : Entity_Id := Base_Type (Entity (Pref));
3252 -- Deal with zero/non-zero boolean values
3254 if Is_Boolean_Type (Etyp) then
3255 Adjust_Condition (First (Exprs));
3256 Etyp := Standard_Boolean;
3257 Set_Prefix (N, New_Occurrence_Of (Standard_Boolean, Loc));
3260 -- Case of enumeration type
3262 if Is_Enumeration_Type (Etyp) then
3264 -- Non-standard enumeration type (generate call)
3266 if Present (Enum_Pos_To_Rep (Etyp)) then
3267 Append_To (Exprs, Rep_To_Pos_Flag (Etyp, Loc));
3270 Make_Function_Call (Loc,
3272 New_Reference_To (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3273 Parameter_Associations => Exprs)));
3275 Analyze_And_Resolve (N, Typ);
3277 -- Standard enumeration type (do universal integer check)
3280 Apply_Universal_Integer_Attribute_Checks (N);
3283 -- Deal with integer types (replace by conversion)
3285 elsif Is_Integer_Type (Etyp) then
3286 Rewrite (N, Convert_To (Typ, First (Exprs)));
3287 Analyze_And_Resolve (N, Typ);
3296 -- We compute this if a component clause was present, otherwise we leave
3297 -- the computation up to the back end, since we don't know what layout
3300 when Attribute_Position => Position :
3302 CE : constant Entity_Id := Entity (Selector_Name (Pref));
3305 if Present (Component_Clause (CE)) then
3307 Make_Integer_Literal (Loc,
3308 Intval => Component_Bit_Offset (CE) / System_Storage_Unit));
3309 Analyze_And_Resolve (N, Typ);
3312 Apply_Universal_Integer_Attribute_Checks (N);
3320 -- 1. Deal with enumeration types with holes
3321 -- 2. For floating-point, generate call to attribute function
3322 -- 3. For other cases, deal with constraint checking
3324 when Attribute_Pred => Pred :
3326 Etyp : constant Entity_Id := Base_Type (Ptyp);
3330 -- For enumeration types with non-standard representations, we
3331 -- expand typ'Pred (x) into
3333 -- Pos_To_Rep (Rep_To_Pos (x) - 1)
3335 -- If the representation is contiguous, we compute instead
3336 -- Lit1 + Rep_to_Pos (x -1), to catch invalid representations.
3337 -- The conversion function Enum_Pos_To_Rep is defined on the
3338 -- base type, not the subtype, so we have to use the base type
3339 -- explicitly for this and other enumeration attributes.
3341 if Is_Enumeration_Type (Ptyp)
3342 and then Present (Enum_Pos_To_Rep (Etyp))
3344 if Has_Contiguous_Rep (Etyp) then
3346 Unchecked_Convert_To (Ptyp,
3349 Make_Integer_Literal (Loc,
3350 Enumeration_Rep (First_Literal (Ptyp))),
3352 Make_Function_Call (Loc,
3355 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3357 Parameter_Associations =>
3359 Unchecked_Convert_To (Ptyp,
3360 Make_Op_Subtract (Loc,
3362 Unchecked_Convert_To (Standard_Integer,
3363 Relocate_Node (First (Exprs))),
3365 Make_Integer_Literal (Loc, 1))),
3366 Rep_To_Pos_Flag (Ptyp, Loc))))));
3369 -- Add Boolean parameter True, to request program errror if
3370 -- we have a bad representation on our hands. If checks are
3371 -- suppressed, then add False instead
3373 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
3375 Make_Indexed_Component (Loc,
3378 (Enum_Pos_To_Rep (Etyp), Loc),
3379 Expressions => New_List (
3380 Make_Op_Subtract (Loc,
3382 Make_Function_Call (Loc,
3385 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
3386 Parameter_Associations => Exprs),
3387 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
3390 Analyze_And_Resolve (N, Typ);
3392 -- For floating-point, we transform 'Pred into a call to the Pred
3393 -- floating-point attribute function in Fat_xxx (xxx is root type)
3395 elsif Is_Floating_Point_Type (Ptyp) then
3396 Expand_Fpt_Attribute_R (N);
3397 Analyze_And_Resolve (N, Typ);
3399 -- For modular types, nothing to do (no overflow, since wraps)
3401 elsif Is_Modular_Integer_Type (Ptyp) then
3404 -- For other types, if argument is marked as needing a range check or
3405 -- overflow checking is enabled, we must generate a check.
3407 elsif not Overflow_Checks_Suppressed (Ptyp)
3408 or else Do_Range_Check (First (Exprs))
3410 Set_Do_Range_Check (First (Exprs), False);
3411 Expand_Pred_Succ (N);
3419 -- Ada 2005 (AI-327): Dynamic ceiling priorities
3421 -- We rewrite X'Priority as the following run-time call:
3423 -- Get_Ceiling (X._Object)
3425 -- Note that although X'Priority is notionally an object, it is quite
3426 -- deliberately not defined as an aliased object in the RM. This means
3427 -- that it works fine to rewrite it as a call, without having to worry
3428 -- about complications that would other arise from X'Priority'Access,
3429 -- which is illegal, because of the lack of aliasing.
3431 when Attribute_Priority =>
3434 Conctyp : Entity_Id;
3435 Object_Parm : Node_Id;
3437 RT_Subprg_Name : Node_Id;
3440 -- Look for the enclosing concurrent type
3442 Conctyp := Current_Scope;
3443 while not Is_Concurrent_Type (Conctyp) loop
3444 Conctyp := Scope (Conctyp);
3447 pragma Assert (Is_Protected_Type (Conctyp));
3449 -- Generate the actual of the call
3451 Subprg := Current_Scope;
3452 while not Present (Protected_Body_Subprogram (Subprg)) loop
3453 Subprg := Scope (Subprg);
3456 -- Use of 'Priority inside protected entries and barriers (in
3457 -- both cases the type of the first formal of their expanded
3458 -- subprogram is Address)
3460 if Etype (First_Entity (Protected_Body_Subprogram (Subprg)))
3464 New_Itype : Entity_Id;
3467 -- In the expansion of protected entries the type of the
3468 -- first formal of the Protected_Body_Subprogram is an
3469 -- Address. In order to reference the _object component
3472 -- type T is access p__ptTV;
3475 New_Itype := Create_Itype (E_Access_Type, N);
3476 Set_Etype (New_Itype, New_Itype);
3477 Set_Directly_Designated_Type (New_Itype,
3478 Corresponding_Record_Type (Conctyp));
3479 Freeze_Itype (New_Itype, N);
3482 -- T!(O)._object'unchecked_access
3485 Make_Attribute_Reference (Loc,
3487 Make_Selected_Component (Loc,
3489 Unchecked_Convert_To (New_Itype,
3492 (Protected_Body_Subprogram (Subprg)),
3495 Make_Identifier (Loc, Name_uObject)),
3496 Attribute_Name => Name_Unchecked_Access);
3499 -- Use of 'Priority inside a protected subprogram
3503 Make_Attribute_Reference (Loc,
3505 Make_Selected_Component (Loc,
3506 Prefix => New_Reference_To
3508 (Protected_Body_Subprogram (Subprg)),
3511 Make_Identifier (Loc, Name_uObject)),
3512 Attribute_Name => Name_Unchecked_Access);
3515 -- Select the appropriate run-time subprogram
3517 if Number_Entries (Conctyp) = 0 then
3519 New_Reference_To (RTE (RE_Get_Ceiling), Loc);
3522 New_Reference_To (RTE (RO_PE_Get_Ceiling), Loc);
3526 Make_Function_Call (Loc,
3527 Name => RT_Subprg_Name,
3528 Parameter_Associations => New_List (Object_Parm));
3532 -- Avoid the generation of extra checks on the pointer to the
3533 -- protected object.
3535 Analyze_And_Resolve (N, Typ, Suppress => Access_Check);
3542 when Attribute_Range_Length => Range_Length : begin
3543 -- The only special processing required is for the case where
3544 -- Range_Length is applied to an enumeration type with holes.
3545 -- In this case we transform
3551 -- X'Pos (X'Last) - X'Pos (X'First) + 1
3553 -- So that the result reflects the proper Pos values instead
3554 -- of the underlying representations.
3556 if Is_Enumeration_Type (Ptyp)
3557 and then Has_Non_Standard_Rep (Ptyp)
3562 Make_Op_Subtract (Loc,
3564 Make_Attribute_Reference (Loc,
3565 Attribute_Name => Name_Pos,
3566 Prefix => New_Occurrence_Of (Ptyp, Loc),
3567 Expressions => New_List (
3568 Make_Attribute_Reference (Loc,
3569 Attribute_Name => Name_Last,
3570 Prefix => New_Occurrence_Of (Ptyp, Loc)))),
3573 Make_Attribute_Reference (Loc,
3574 Attribute_Name => Name_Pos,
3575 Prefix => New_Occurrence_Of (Ptyp, Loc),
3576 Expressions => New_List (
3577 Make_Attribute_Reference (Loc,
3578 Attribute_Name => Name_First,
3579 Prefix => New_Occurrence_Of (Ptyp, Loc))))),
3582 Make_Integer_Literal (Loc, 1)));
3584 Analyze_And_Resolve (N, Typ);
3586 -- For all other cases, the attribute is handled by the back end, but
3587 -- we need to deal with the case of the range check on a universal
3591 Apply_Universal_Integer_Attribute_Checks (N);
3599 when Attribute_Read => Read : declare
3600 P_Type : constant Entity_Id := Entity (Pref);
3601 B_Type : constant Entity_Id := Base_Type (P_Type);
3602 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3612 -- If no underlying type, we have an error that will be diagnosed
3613 -- elsewhere, so here we just completely ignore the expansion.
3619 -- The simple case, if there is a TSS for Read, just call it
3621 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Read);
3623 if Present (Pname) then
3627 -- If there is a Stream_Convert pragma, use it, we rewrite
3629 -- sourcetyp'Read (stream, Item)
3633 -- Item := sourcetyp (strmread (strmtyp'Input (Stream)));
3635 -- where strmread is the given Read function that converts an
3636 -- argument of type strmtyp to type sourcetyp or a type from which
3637 -- it is derived. The conversion to sourcetyp is required in the
3640 -- A special case arises if Item is a type conversion in which
3641 -- case, we have to expand to:
3643 -- Itemx := typex (strmread (strmtyp'Input (Stream)));
3645 -- where Itemx is the expression of the type conversion (i.e.
3646 -- the actual object), and typex is the type of Itemx.
3648 Prag := Get_Stream_Convert_Pragma (P_Type);
3650 if Present (Prag) then
3651 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
3652 Rfunc := Entity (Expression (Arg2));
3653 Lhs := Relocate_Node (Next (First (Exprs)));
3655 OK_Convert_To (B_Type,
3656 Make_Function_Call (Loc,
3657 Name => New_Occurrence_Of (Rfunc, Loc),
3658 Parameter_Associations => New_List (
3659 Make_Attribute_Reference (Loc,
3662 (Etype (First_Formal (Rfunc)), Loc),
3663 Attribute_Name => Name_Input,
3664 Expressions => New_List (
3665 Relocate_Node (First (Exprs)))))));
3667 if Nkind (Lhs) = N_Type_Conversion then
3668 Lhs := Expression (Lhs);
3669 Rhs := Convert_To (Etype (Lhs), Rhs);
3673 Make_Assignment_Statement (Loc,
3675 Expression => Rhs));
3676 Set_Assignment_OK (Lhs);
3680 -- For elementary types, we call the I_xxx routine using the first
3681 -- parameter and then assign the result into the second parameter.
3682 -- We set Assignment_OK to deal with the conversion case.
3684 elsif Is_Elementary_Type (U_Type) then
3690 Lhs := Relocate_Node (Next (First (Exprs)));
3691 Rhs := Build_Elementary_Input_Call (N);
3693 if Nkind (Lhs) = N_Type_Conversion then
3694 Lhs := Expression (Lhs);
3695 Rhs := Convert_To (Etype (Lhs), Rhs);
3698 Set_Assignment_OK (Lhs);
3701 Make_Assignment_Statement (Loc,
3703 Expression => Rhs));
3711 elsif Is_Array_Type (U_Type) then
3712 Build_Array_Read_Procedure (N, U_Type, Decl, Pname);
3713 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3715 -- Tagged type case, use the primitive Read function. Note that
3716 -- this will dispatch in the class-wide case which is what we want
3718 elsif Is_Tagged_Type (U_Type) then
3719 Pname := Find_Prim_Op (U_Type, TSS_Stream_Read);
3721 -- All other record type cases, including protected records. The
3722 -- latter only arise for expander generated code for handling
3723 -- shared passive partition access.
3727 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3729 -- Ada 2005 (AI-216): Program_Error is raised when executing
3730 -- the default implementation of the Read attribute of an
3731 -- Unchecked_Union type.
3733 if Is_Unchecked_Union (Base_Type (U_Type)) then
3735 Make_Raise_Program_Error (Loc,
3736 Reason => PE_Unchecked_Union_Restriction));
3739 if Has_Discriminants (U_Type)
3741 (Discriminant_Default_Value (First_Discriminant (U_Type)))
3743 Build_Mutable_Record_Read_Procedure
3744 (Loc, Base_Type (U_Type), Decl, Pname);
3746 Build_Record_Read_Procedure
3747 (Loc, Base_Type (U_Type), Decl, Pname);
3750 -- Suppress checks, uninitialized or otherwise invalid
3751 -- data does not cause constraint errors to be raised for
3752 -- a complete record read.
3754 Insert_Action (N, Decl, All_Checks);
3758 Rewrite_Stream_Proc_Call (Pname);
3765 -- Transforms 'Remainder into a call to the floating-point attribute
3766 -- function Remainder in Fat_xxx (where xxx is the root type)
3768 when Attribute_Remainder =>
3769 Expand_Fpt_Attribute_RR (N);
3775 -- Transform 'Result into reference to _Result formal. At the point
3776 -- where a legal 'Result attribute is expanded, we know that we are in
3777 -- the context of a _Postcondition function with a _Result parameter.
3779 when Attribute_Result =>
3781 Make_Identifier (Loc,
3782 Chars => Name_uResult));
3783 Analyze_And_Resolve (N, Typ);
3789 -- The handling of the Round attribute is quite delicate. The processing
3790 -- in Sem_Attr introduced a conversion to universal real, reflecting the
3791 -- semantics of Round, but we do not want anything to do with universal
3792 -- real at runtime, since this corresponds to using floating-point
3795 -- What we have now is that the Etype of the Round attribute correctly
3796 -- indicates the final result type. The operand of the Round is the
3797 -- conversion to universal real, described above, and the operand of
3798 -- this conversion is the actual operand of Round, which may be the
3799 -- special case of a fixed point multiplication or division (Etype =
3802 -- The exapander will expand first the operand of the conversion, then
3803 -- the conversion, and finally the round attribute itself, since we
3804 -- always work inside out. But we cannot simply process naively in this
3805 -- order. In the semantic world where universal fixed and real really
3806 -- exist and have infinite precision, there is no problem, but in the
3807 -- implementation world, where universal real is a floating-point type,
3808 -- we would get the wrong result.
3810 -- So the approach is as follows. First, when expanding a multiply or
3811 -- divide whose type is universal fixed, we do nothing at all, instead
3812 -- deferring the operation till later.
3814 -- The actual processing is done in Expand_N_Type_Conversion which
3815 -- handles the special case of Round by looking at its parent to see if
3816 -- it is a Round attribute, and if it is, handling the conversion (or
3817 -- its fixed multiply/divide child) in an appropriate manner.
3819 -- This means that by the time we get to expanding the Round attribute
3820 -- itself, the Round is nothing more than a type conversion (and will
3821 -- often be a null type conversion), so we just replace it with the
3822 -- appropriate conversion operation.
3824 when Attribute_Round =>
3826 Convert_To (Etype (N), Relocate_Node (First (Exprs))));
3827 Analyze_And_Resolve (N);
3833 -- Transforms 'Rounding into a call to the floating-point attribute
3834 -- function Rounding in Fat_xxx (where xxx is the root type)
3836 when Attribute_Rounding =>
3837 Expand_Fpt_Attribute_R (N);
3843 -- Transforms 'Scaling into a call to the floating-point attribute
3844 -- function Scaling in Fat_xxx (where xxx is the root type)
3846 when Attribute_Scaling =>
3847 Expand_Fpt_Attribute_RI (N);
3853 when Attribute_Size |
3854 Attribute_Object_Size |
3855 Attribute_Value_Size |
3856 Attribute_VADS_Size => Size :
3863 -- Processing for VADS_Size case. Note that this processing removes
3864 -- all traces of VADS_Size from the tree, and completes all required
3865 -- processing for VADS_Size by translating the attribute reference
3866 -- to an appropriate Size or Object_Size reference.
3868 if Id = Attribute_VADS_Size
3869 or else (Use_VADS_Size and then Id = Attribute_Size)
3871 -- If the size is specified, then we simply use the specified
3872 -- size. This applies to both types and objects. The size of an
3873 -- object can be specified in the following ways:
3875 -- An explicit size object is given for an object
3876 -- A component size is specified for an indexed component
3877 -- A component clause is specified for a selected component
3878 -- The object is a component of a packed composite object
3880 -- If the size is specified, then VADS_Size of an object
3882 if (Is_Entity_Name (Pref)
3883 and then Present (Size_Clause (Entity (Pref))))
3885 (Nkind (Pref) = N_Component_Clause
3886 and then (Present (Component_Clause
3887 (Entity (Selector_Name (Pref))))
3888 or else Is_Packed (Etype (Prefix (Pref)))))
3890 (Nkind (Pref) = N_Indexed_Component
3891 and then (Component_Size (Etype (Prefix (Pref))) /= 0
3892 or else Is_Packed (Etype (Prefix (Pref)))))
3894 Set_Attribute_Name (N, Name_Size);
3896 -- Otherwise if we have an object rather than a type, then the
3897 -- VADS_Size attribute applies to the type of the object, rather
3898 -- than the object itself. This is one of the respects in which
3899 -- VADS_Size differs from Size.
3902 if (not Is_Entity_Name (Pref)
3903 or else not Is_Type (Entity (Pref)))
3904 and then (Is_Scalar_Type (Ptyp) or else Is_Constrained (Ptyp))
3906 Rewrite (Pref, New_Occurrence_Of (Ptyp, Loc));
3909 -- For a scalar type for which no size was explicitly given,
3910 -- VADS_Size means Object_Size. This is the other respect in
3911 -- which VADS_Size differs from Size.
3913 if Is_Scalar_Type (Ptyp) and then No (Size_Clause (Ptyp)) then
3914 Set_Attribute_Name (N, Name_Object_Size);
3916 -- In all other cases, Size and VADS_Size are the sane
3919 Set_Attribute_Name (N, Name_Size);
3924 -- For class-wide types, X'Class'Size is transformed into a direct
3925 -- reference to the Size of the class type, so that the back end does
3926 -- not have to deal with the X'Class'Size reference.
3928 if Is_Entity_Name (Pref)
3929 and then Is_Class_Wide_Type (Entity (Pref))
3931 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
3934 -- For X'Size applied to an object of a class-wide type, transform
3935 -- X'Size into a call to the primitive operation _Size applied to X.
3937 elsif Is_Class_Wide_Type (Ptyp)
3938 or else (Id = Attribute_Size
3939 and then Is_Tagged_Type (Ptyp)
3940 and then Has_Unknown_Discriminants (Ptyp))
3942 -- No need to do anything else compiling under restriction
3943 -- No_Dispatching_Calls. During the semantic analysis we
3944 -- already notified such violation.
3946 if Restriction_Active (No_Dispatching_Calls) then
3951 Make_Function_Call (Loc,
3952 Name => New_Reference_To
3953 (Find_Prim_Op (Ptyp, Name_uSize), Loc),
3954 Parameter_Associations => New_List (Pref));
3956 if Typ /= Standard_Long_Long_Integer then
3958 -- The context is a specific integer type with which the
3959 -- original attribute was compatible. The function has a
3960 -- specific type as well, so to preserve the compatibility
3961 -- we must convert explicitly.
3963 New_Node := Convert_To (Typ, New_Node);
3966 Rewrite (N, New_Node);
3967 Analyze_And_Resolve (N, Typ);
3970 -- Case of known RM_Size of a type
3972 elsif (Id = Attribute_Size or else Id = Attribute_Value_Size)
3973 and then Is_Entity_Name (Pref)
3974 and then Is_Type (Entity (Pref))
3975 and then Known_Static_RM_Size (Entity (Pref))
3977 Siz := RM_Size (Entity (Pref));
3979 -- Case of known Esize of a type
3981 elsif Id = Attribute_Object_Size
3982 and then Is_Entity_Name (Pref)
3983 and then Is_Type (Entity (Pref))
3984 and then Known_Static_Esize (Entity (Pref))
3986 Siz := Esize (Entity (Pref));
3988 -- Case of known size of object
3990 elsif Id = Attribute_Size
3991 and then Is_Entity_Name (Pref)
3992 and then Is_Object (Entity (Pref))
3993 and then Known_Esize (Entity (Pref))
3994 and then Known_Static_Esize (Entity (Pref))
3996 Siz := Esize (Entity (Pref));
3998 -- For an array component, we can do Size in the front end
3999 -- if the component_size of the array is set.
4001 elsif Nkind (Pref) = N_Indexed_Component then
4002 Siz := Component_Size (Etype (Prefix (Pref)));
4004 -- For a record component, we can do Size in the front end if there
4005 -- is a component clause, or if the record is packed and the
4006 -- component's size is known at compile time.
4008 elsif Nkind (Pref) = N_Selected_Component then
4010 Rec : constant Entity_Id := Etype (Prefix (Pref));
4011 Comp : constant Entity_Id := Entity (Selector_Name (Pref));
4014 if Present (Component_Clause (Comp)) then
4015 Siz := Esize (Comp);
4017 elsif Is_Packed (Rec) then
4018 Siz := RM_Size (Ptyp);
4021 Apply_Universal_Integer_Attribute_Checks (N);
4026 -- All other cases are handled by the back end
4029 Apply_Universal_Integer_Attribute_Checks (N);
4031 -- If Size is applied to a formal parameter that is of a packed
4032 -- array subtype, then apply Size to the actual subtype.
4034 if Is_Entity_Name (Pref)
4035 and then Is_Formal (Entity (Pref))
4036 and then Is_Array_Type (Ptyp)
4037 and then Is_Packed (Ptyp)
4040 Make_Attribute_Reference (Loc,
4042 New_Occurrence_Of (Get_Actual_Subtype (Pref), Loc),
4043 Attribute_Name => Name_Size));
4044 Analyze_And_Resolve (N, Typ);
4047 -- If Size applies to a dereference of an access to unconstrained
4048 -- packed array, the back end needs to see its unconstrained
4049 -- nominal type, but also a hint to the actual constrained type.
4051 if Nkind (Pref) = N_Explicit_Dereference
4052 and then Is_Array_Type (Ptyp)
4053 and then not Is_Constrained (Ptyp)
4054 and then Is_Packed (Ptyp)
4056 Set_Actual_Designated_Subtype (Pref,
4057 Get_Actual_Subtype (Pref));
4063 -- Common processing for record and array component case
4065 if Siz /= No_Uint and then Siz /= 0 then
4067 CS : constant Boolean := Comes_From_Source (N);
4070 Rewrite (N, Make_Integer_Literal (Loc, Siz));
4072 -- This integer literal is not a static expression. We do not
4073 -- call Analyze_And_Resolve here, because this would activate
4074 -- the circuit for deciding that a static value was out of
4075 -- range, and we don't want that.
4077 -- So just manually set the type, mark the expression as non-
4078 -- static, and then ensure that the result is checked properly
4079 -- if the attribute comes from source (if it was internally
4080 -- generated, we never need a constraint check).
4083 Set_Is_Static_Expression (N, False);
4086 Apply_Constraint_Check (N, Typ);
4096 when Attribute_Storage_Pool =>
4098 Make_Type_Conversion (Loc,
4099 Subtype_Mark => New_Reference_To (Etype (N), Loc),
4100 Expression => New_Reference_To (Entity (N), Loc)));
4101 Analyze_And_Resolve (N, Typ);
4107 when Attribute_Storage_Size => Storage_Size : begin
4109 -- Access type case, always go to the root type
4111 -- The case of access types results in a value of zero for the case
4112 -- where no storage size attribute clause has been given. If a
4113 -- storage size has been given, then the attribute is converted
4114 -- to a reference to the variable used to hold this value.
4116 if Is_Access_Type (Ptyp) then
4117 if Present (Storage_Size_Variable (Root_Type (Ptyp))) then
4119 Make_Attribute_Reference (Loc,
4120 Prefix => New_Reference_To (Typ, Loc),
4121 Attribute_Name => Name_Max,
4122 Expressions => New_List (
4123 Make_Integer_Literal (Loc, 0),
4126 (Storage_Size_Variable (Root_Type (Ptyp)), Loc)))));
4128 elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then
4131 Make_Function_Call (Loc,
4135 (Etype (Associated_Storage_Pool (Root_Type (Ptyp))),
4136 Attribute_Name (N)),
4139 Parameter_Associations => New_List (
4141 (Associated_Storage_Pool (Root_Type (Ptyp)), Loc)))));
4144 Rewrite (N, Make_Integer_Literal (Loc, 0));
4147 Analyze_And_Resolve (N, Typ);
4149 -- For tasks, we retrieve the size directly from the TCB. The
4150 -- size may depend on a discriminant of the type, and therefore
4151 -- can be a per-object expression, so type-level information is
4152 -- not sufficient in general. There are four cases to consider:
4154 -- a) If the attribute appears within a task body, the designated
4155 -- TCB is obtained by a call to Self.
4157 -- b) If the prefix of the attribute is the name of a task object,
4158 -- the designated TCB is the one stored in the corresponding record.
4160 -- c) If the prefix is a task type, the size is obtained from the
4161 -- size variable created for each task type
4163 -- d) If no storage_size was specified for the type , there is no
4164 -- size variable, and the value is a system-specific default.
4167 if In_Open_Scopes (Ptyp) then
4169 -- Storage_Size (Self)
4173 Make_Function_Call (Loc,
4175 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4176 Parameter_Associations =>
4178 Make_Function_Call (Loc,
4180 New_Reference_To (RTE (RE_Self), Loc))))));
4182 elsif not Is_Entity_Name (Pref)
4183 or else not Is_Type (Entity (Pref))
4185 -- Storage_Size (Rec (Obj).Size)
4189 Make_Function_Call (Loc,
4191 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
4192 Parameter_Associations =>
4194 Make_Selected_Component (Loc,
4196 Unchecked_Convert_To (
4197 Corresponding_Record_Type (Ptyp),
4198 New_Copy_Tree (Pref)),
4200 Make_Identifier (Loc, Name_uTask_Id))))));
4202 elsif Present (Storage_Size_Variable (Ptyp)) then
4204 -- Static storage size pragma given for type: retrieve value
4205 -- from its allocated storage variable.
4209 Make_Function_Call (Loc,
4210 Name => New_Occurrence_Of (
4211 RTE (RE_Adjust_Storage_Size), Loc),
4212 Parameter_Associations =>
4215 Storage_Size_Variable (Ptyp), Loc)))));
4217 -- Get system default
4221 Make_Function_Call (Loc,
4224 RTE (RE_Default_Stack_Size), Loc))));
4227 Analyze_And_Resolve (N, Typ);
4235 when Attribute_Stream_Size => Stream_Size : declare
4239 -- If we have a Stream_Size clause for this type use it, otherwise
4240 -- the Stream_Size if the size of the type.
4242 if Has_Stream_Size_Clause (Ptyp) then
4245 (Static_Integer (Expression (Stream_Size_Clause (Ptyp))));
4247 Size := UI_To_Int (Esize (Ptyp));
4250 Rewrite (N, Make_Integer_Literal (Loc, Intval => Size));
4251 Analyze_And_Resolve (N, Typ);
4258 -- 1. Deal with enumeration types with holes
4259 -- 2. For floating-point, generate call to attribute function
4260 -- 3. For other cases, deal with constraint checking
4262 when Attribute_Succ => Succ :
4264 Etyp : constant Entity_Id := Base_Type (Ptyp);
4268 -- For enumeration types with non-standard representations, we
4269 -- expand typ'Succ (x) into
4271 -- Pos_To_Rep (Rep_To_Pos (x) + 1)
4273 -- If the representation is contiguous, we compute instead
4274 -- Lit1 + Rep_to_Pos (x+1), to catch invalid representations.
4276 if Is_Enumeration_Type (Ptyp)
4277 and then Present (Enum_Pos_To_Rep (Etyp))
4279 if Has_Contiguous_Rep (Etyp) then
4281 Unchecked_Convert_To (Ptyp,
4284 Make_Integer_Literal (Loc,
4285 Enumeration_Rep (First_Literal (Ptyp))),
4287 Make_Function_Call (Loc,
4290 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4292 Parameter_Associations =>
4294 Unchecked_Convert_To (Ptyp,
4297 Unchecked_Convert_To (Standard_Integer,
4298 Relocate_Node (First (Exprs))),
4300 Make_Integer_Literal (Loc, 1))),
4301 Rep_To_Pos_Flag (Ptyp, Loc))))));
4303 -- Add Boolean parameter True, to request program errror if
4304 -- we have a bad representation on our hands. Add False if
4305 -- checks are suppressed.
4307 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
4309 Make_Indexed_Component (Loc,
4312 (Enum_Pos_To_Rep (Etyp), Loc),
4313 Expressions => New_List (
4316 Make_Function_Call (Loc,
4319 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4320 Parameter_Associations => Exprs),
4321 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
4324 Analyze_And_Resolve (N, Typ);
4326 -- For floating-point, we transform 'Succ into a call to the Succ
4327 -- floating-point attribute function in Fat_xxx (xxx is root type)
4329 elsif Is_Floating_Point_Type (Ptyp) then
4330 Expand_Fpt_Attribute_R (N);
4331 Analyze_And_Resolve (N, Typ);
4333 -- For modular types, nothing to do (no overflow, since wraps)
4335 elsif Is_Modular_Integer_Type (Ptyp) then
4338 -- For other types, if argument is marked as needing a range check or
4339 -- overflow checking is enabled, we must generate a check.
4341 elsif not Overflow_Checks_Suppressed (Ptyp)
4342 or else Do_Range_Check (First (Exprs))
4344 Set_Do_Range_Check (First (Exprs), False);
4345 Expand_Pred_Succ (N);
4353 -- Transforms X'Tag into a direct reference to the tag of X
4355 when Attribute_Tag => Tag :
4358 Prefix_Is_Type : Boolean;
4361 if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then
4362 Ttyp := Entity (Pref);
4363 Prefix_Is_Type := True;
4366 Prefix_Is_Type := False;
4369 if Is_Class_Wide_Type (Ttyp) then
4370 Ttyp := Root_Type (Ttyp);
4373 Ttyp := Underlying_Type (Ttyp);
4375 -- Ada 2005: The type may be a synchronized tagged type, in which
4376 -- case the tag information is stored in the corresponding record.
4378 if Is_Concurrent_Type (Ttyp) then
4379 Ttyp := Corresponding_Record_Type (Ttyp);
4382 if Prefix_Is_Type then
4384 -- For VMs we leave the type attribute unexpanded because
4385 -- there's not a dispatching table to reference.
4387 if Tagged_Type_Expansion then
4389 Unchecked_Convert_To (RTE (RE_Tag),
4391 (Node (First_Elmt (Access_Disp_Table (Ttyp))), Loc)));
4392 Analyze_And_Resolve (N, RTE (RE_Tag));
4395 -- Ada 2005 (AI-251): The use of 'Tag in the sources always
4396 -- references the primary tag of the actual object. If 'Tag is
4397 -- applied to class-wide interface objects we generate code that
4398 -- displaces "this" to reference the base of the object.
4400 elsif Comes_From_Source (N)
4401 and then Is_Class_Wide_Type (Etype (Prefix (N)))
4402 and then Is_Interface (Etype (Prefix (N)))
4405 -- (To_Tag_Ptr (Prefix'Address)).all
4407 -- Note that Prefix'Address is recursively expanded into a call
4408 -- to Base_Address (Obj.Tag)
4410 -- Not needed for VM targets, since all handled by the VM
4412 if Tagged_Type_Expansion then
4414 Make_Explicit_Dereference (Loc,
4415 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
4416 Make_Attribute_Reference (Loc,
4417 Prefix => Relocate_Node (Pref),
4418 Attribute_Name => Name_Address))));
4419 Analyze_And_Resolve (N, RTE (RE_Tag));
4424 Make_Selected_Component (Loc,
4425 Prefix => Relocate_Node (Pref),
4427 New_Reference_To (First_Tag_Component (Ttyp), Loc)));
4428 Analyze_And_Resolve (N, RTE (RE_Tag));
4436 -- Transforms 'Terminated attribute into a call to Terminated function
4438 when Attribute_Terminated => Terminated :
4440 -- The prefix of Terminated is of a task interface class-wide type.
4442 -- terminated (Task_Id (Pref._disp_get_task_id));
4444 if Ada_Version >= Ada_05
4445 and then Ekind (Ptyp) = E_Class_Wide_Type
4446 and then Is_Interface (Ptyp)
4447 and then Is_Task_Interface (Ptyp)
4450 Make_Function_Call (Loc,
4452 New_Reference_To (RTE (RE_Terminated), Loc),
4453 Parameter_Associations => New_List (
4454 Make_Unchecked_Type_Conversion (Loc,
4456 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
4458 Make_Selected_Component (Loc,
4460 New_Copy_Tree (Pref),
4462 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
4464 elsif Restricted_Profile then
4466 Build_Call_With_Task (Pref, RTE (RE_Restricted_Terminated)));
4470 Build_Call_With_Task (Pref, RTE (RE_Terminated)));
4473 Analyze_And_Resolve (N, Standard_Boolean);
4480 -- Transforms System'To_Address (X) into unchecked conversion
4481 -- from (integral) type of X to type address.
4483 when Attribute_To_Address =>
4485 Unchecked_Convert_To (RTE (RE_Address),
4486 Relocate_Node (First (Exprs))));
4487 Analyze_And_Resolve (N, RTE (RE_Address));
4493 when Attribute_To_Any => To_Any : declare
4494 P_Type : constant Entity_Id := Etype (Pref);
4495 Decls : constant List_Id := New_List;
4499 (Convert_To (P_Type,
4500 Relocate_Node (First (Exprs))), Decls));
4501 Insert_Actions (N, Decls);
4502 Analyze_And_Resolve (N, RTE (RE_Any));
4509 -- Transforms 'Truncation into a call to the floating-point attribute
4510 -- function Truncation in Fat_xxx (where xxx is the root type).
4511 -- Expansion is avoided for cases the back end can handle directly.
4513 when Attribute_Truncation =>
4514 if not Is_Inline_Floating_Point_Attribute (N) then
4515 Expand_Fpt_Attribute_R (N);
4522 when Attribute_TypeCode => TypeCode : declare
4523 P_Type : constant Entity_Id := Etype (Pref);
4524 Decls : constant List_Id := New_List;
4526 Rewrite (N, Build_TypeCode_Call (Loc, P_Type, Decls));
4527 Insert_Actions (N, Decls);
4528 Analyze_And_Resolve (N, RTE (RE_TypeCode));
4531 -----------------------
4532 -- Unbiased_Rounding --
4533 -----------------------
4535 -- Transforms 'Unbiased_Rounding into a call to the floating-point
4536 -- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the
4537 -- root type). Expansion is avoided for cases the back end can handle
4540 when Attribute_Unbiased_Rounding =>
4541 if not Is_Inline_Floating_Point_Attribute (N) then
4542 Expand_Fpt_Attribute_R (N);
4549 when Attribute_UET_Address => UET_Address : declare
4550 Ent : constant Entity_Id :=
4551 Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
4555 Make_Object_Declaration (Loc,
4556 Defining_Identifier => Ent,
4557 Aliased_Present => True,
4558 Object_Definition =>
4559 New_Occurrence_Of (RTE (RE_Address), Loc)));
4561 -- Construct name __gnat_xxx__SDP, where xxx is the unit name
4562 -- in normal external form.
4564 Get_External_Unit_Name_String (Get_Unit_Name (Pref));
4565 Name_Buffer (1 + 7 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
4566 Name_Len := Name_Len + 7;
4567 Name_Buffer (1 .. 7) := "__gnat_";
4568 Name_Buffer (Name_Len + 1 .. Name_Len + 5) := "__SDP";
4569 Name_Len := Name_Len + 5;
4571 Set_Is_Imported (Ent);
4572 Set_Interface_Name (Ent,
4573 Make_String_Literal (Loc,
4574 Strval => String_From_Name_Buffer));
4576 -- Set entity as internal to ensure proper Sprint output of its
4577 -- implicit importation.
4579 Set_Is_Internal (Ent);
4582 Make_Attribute_Reference (Loc,
4583 Prefix => New_Occurrence_Of (Ent, Loc),
4584 Attribute_Name => Name_Address));
4586 Analyze_And_Resolve (N, Typ);
4593 -- The processing for VADS_Size is shared with Size
4599 -- For enumeration types with a standard representation, and for all
4600 -- other types, Val is handled by the back end. For enumeration types
4601 -- with a non-standard representation we use the _Pos_To_Rep array that
4602 -- was created when the type was frozen.
4604 when Attribute_Val => Val :
4606 Etyp : constant Entity_Id := Base_Type (Entity (Pref));
4609 if Is_Enumeration_Type (Etyp)
4610 and then Present (Enum_Pos_To_Rep (Etyp))
4612 if Has_Contiguous_Rep (Etyp) then
4614 Rep_Node : constant Node_Id :=
4615 Unchecked_Convert_To (Etyp,
4618 Make_Integer_Literal (Loc,
4619 Enumeration_Rep (First_Literal (Etyp))),
4621 (Convert_To (Standard_Integer,
4622 Relocate_Node (First (Exprs))))));
4626 Unchecked_Convert_To (Etyp,
4629 Make_Integer_Literal (Loc,
4630 Enumeration_Rep (First_Literal (Etyp))),
4632 Make_Function_Call (Loc,
4635 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4636 Parameter_Associations => New_List (
4638 Rep_To_Pos_Flag (Etyp, Loc))))));
4643 Make_Indexed_Component (Loc,
4644 Prefix => New_Reference_To (Enum_Pos_To_Rep (Etyp), Loc),
4645 Expressions => New_List (
4646 Convert_To (Standard_Integer,
4647 Relocate_Node (First (Exprs))))));
4650 Analyze_And_Resolve (N, Typ);
4652 -- If the argument is marked as requiring a range check then generate
4655 elsif Do_Range_Check (First (Exprs)) then
4656 Set_Do_Range_Check (First (Exprs), False);
4657 Generate_Range_Check (First (Exprs), Etyp, CE_Range_Check_Failed);
4665 -- The code for valid is dependent on the particular types involved.
4666 -- See separate sections below for the generated code in each case.
4668 when Attribute_Valid => Valid :
4670 Btyp : Entity_Id := Base_Type (Ptyp);
4673 Save_Validity_Checks_On : constant Boolean := Validity_Checks_On;
4674 -- Save the validity checking mode. We always turn off validity
4675 -- checking during process of 'Valid since this is one place
4676 -- where we do not want the implicit validity checks to intefere
4677 -- with the explicit validity check that the programmer is doing.
4679 function Make_Range_Test return Node_Id;
4680 -- Build the code for a range test of the form
4681 -- Btyp!(Pref) >= Btyp!(Ptyp'First)
4683 -- Btyp!(Pref) <= Btyp!(Ptyp'Last)
4685 ---------------------
4686 -- Make_Range_Test --
4687 ---------------------
4689 function Make_Range_Test return Node_Id is
4690 Temp : constant Node_Id := Duplicate_Subexpr (Pref);
4693 -- The value whose validity is being checked has been captured in
4694 -- an object declaration. We certainly don't want this object to
4695 -- appear valid because the declaration initializes it!
4697 if Is_Entity_Name (Temp) then
4698 Set_Is_Known_Valid (Entity (Temp), False);
4706 Unchecked_Convert_To (Btyp, Temp),
4709 Unchecked_Convert_To (Btyp,
4710 Make_Attribute_Reference (Loc,
4711 Prefix => New_Occurrence_Of (Ptyp, Loc),
4712 Attribute_Name => Name_First))),
4717 Unchecked_Convert_To (Btyp, Temp),
4720 Unchecked_Convert_To (Btyp,
4721 Make_Attribute_Reference (Loc,
4722 Prefix => New_Occurrence_Of (Ptyp, Loc),
4723 Attribute_Name => Name_Last))));
4724 end Make_Range_Test;
4726 -- Start of processing for Attribute_Valid
4729 -- Turn off validity checks. We do not want any implicit validity
4730 -- checks to intefere with the explicit check from the attribute
4732 Validity_Checks_On := False;
4734 -- Floating-point case. This case is handled by the Valid attribute
4735 -- code in the floating-point attribute run-time library.
4737 if Is_Floating_Point_Type (Ptyp) then
4743 -- For vax fpt types, call appropriate routine in special vax
4744 -- floating point unit. We do not have to worry about loads in
4745 -- this case, since these types have no signalling NaN's.
4747 if Vax_Float (Btyp) then
4748 Expand_Vax_Valid (N);
4750 -- The AAMP back end handles Valid for floating-point types
4752 elsif Is_AAMP_Float (Btyp) then
4753 Analyze_And_Resolve (Pref, Ptyp);
4754 Set_Etype (N, Standard_Boolean);
4757 -- Non VAX float case
4760 Find_Fat_Info (Ptyp, Ftp, Pkg);
4762 -- If the floating-point object might be unaligned, we need
4763 -- to call the special routine Unaligned_Valid, which makes
4764 -- the needed copy, being careful not to load the value into
4765 -- any floating-point register. The argument in this case is
4766 -- obj'Address (see Unaligned_Valid routine in Fat_Gen).
4768 if Is_Possibly_Unaligned_Object (Pref) then
4769 Expand_Fpt_Attribute
4770 (N, Pkg, Name_Unaligned_Valid,
4772 Make_Attribute_Reference (Loc,
4773 Prefix => Relocate_Node (Pref),
4774 Attribute_Name => Name_Address)));
4776 -- In the normal case where we are sure the object is
4777 -- aligned, we generate a call to Valid, and the argument in
4778 -- this case is obj'Unrestricted_Access (after converting
4779 -- obj to the right floating-point type).
4782 Expand_Fpt_Attribute
4783 (N, Pkg, Name_Valid,
4785 Make_Attribute_Reference (Loc,
4786 Prefix => Unchecked_Convert_To (Ftp, Pref),
4787 Attribute_Name => Name_Unrestricted_Access)));
4791 -- One more task, we still need a range check. Required
4792 -- only if we have a constraint, since the Valid routine
4793 -- catches infinities properly (infinities are never valid).
4795 -- The way we do the range check is simply to create the
4796 -- expression: Valid (N) and then Base_Type(Pref) in Typ.
4798 if not Subtypes_Statically_Match (Ptyp, Btyp) then
4801 Left_Opnd => Relocate_Node (N),
4804 Left_Opnd => Convert_To (Btyp, Pref),
4805 Right_Opnd => New_Occurrence_Of (Ptyp, Loc))));
4809 -- Enumeration type with holes
4811 -- For enumeration types with holes, the Pos value constructed by
4812 -- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a
4813 -- second argument of False returns minus one for an invalid value,
4814 -- and the non-negative pos value for a valid value, so the
4815 -- expansion of X'Valid is simply:
4817 -- type(X)'Pos (X) >= 0
4819 -- We can't quite generate it that way because of the requirement
4820 -- for the non-standard second argument of False in the resulting
4821 -- rep_to_pos call, so we have to explicitly create:
4823 -- _rep_to_pos (X, False) >= 0
4825 -- If we have an enumeration subtype, we also check that the
4826 -- value is in range:
4828 -- _rep_to_pos (X, False) >= 0
4830 -- (X >= type(X)'First and then type(X)'Last <= X)
4832 elsif Is_Enumeration_Type (Ptyp)
4833 and then Present (Enum_Pos_To_Rep (Base_Type (Ptyp)))
4838 Make_Function_Call (Loc,
4841 (TSS (Base_Type (Ptyp), TSS_Rep_To_Pos), Loc),
4842 Parameter_Associations => New_List (
4844 New_Occurrence_Of (Standard_False, Loc))),
4845 Right_Opnd => Make_Integer_Literal (Loc, 0));
4849 (Type_Low_Bound (Ptyp) /= Type_Low_Bound (Btyp)
4851 Type_High_Bound (Ptyp) /= Type_High_Bound (Btyp))
4853 -- The call to Make_Range_Test will create declarations
4854 -- that need a proper insertion point, but Pref is now
4855 -- attached to a node with no ancestor. Attach to tree
4856 -- even if it is to be rewritten below.
4858 Set_Parent (Tst, Parent (N));
4862 Left_Opnd => Make_Range_Test,
4868 -- Fortran convention booleans
4870 -- For the very special case of Fortran convention booleans, the
4871 -- value is always valid, since it is an integer with the semantics
4872 -- that non-zero is true, and any value is permissible.
4874 elsif Is_Boolean_Type (Ptyp)
4875 and then Convention (Ptyp) = Convention_Fortran
4877 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
4879 -- For biased representations, we will be doing an unchecked
4880 -- conversion without unbiasing the result. That means that the range
4881 -- test has to take this into account, and the proper form of the
4884 -- Btyp!(Pref) < Btyp!(Ptyp'Range_Length)
4886 elsif Has_Biased_Representation (Ptyp) then
4887 Btyp := RTE (RE_Unsigned_32);
4891 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
4893 Unchecked_Convert_To (Btyp,
4894 Make_Attribute_Reference (Loc,
4895 Prefix => New_Occurrence_Of (Ptyp, Loc),
4896 Attribute_Name => Name_Range_Length))));
4898 -- For all other scalar types, what we want logically is a
4901 -- X in type(X)'First .. type(X)'Last
4903 -- But that's precisely what won't work because of possible
4904 -- unwanted optimization (and indeed the basic motivation for
4905 -- the Valid attribute is exactly that this test does not work!)
4906 -- What will work is:
4908 -- Btyp!(X) >= Btyp!(type(X)'First)
4910 -- Btyp!(X) <= Btyp!(type(X)'Last)
4912 -- where Btyp is an integer type large enough to cover the full
4913 -- range of possible stored values (i.e. it is chosen on the basis
4914 -- of the size of the type, not the range of the values). We write
4915 -- this as two tests, rather than a range check, so that static
4916 -- evaluation will easily remove either or both of the checks if
4917 -- they can be -statically determined to be true (this happens
4918 -- when the type of X is static and the range extends to the full
4919 -- range of stored values).
4921 -- Unsigned types. Note: it is safe to consider only whether the
4922 -- subtype is unsigned, since we will in that case be doing all
4923 -- unsigned comparisons based on the subtype range. Since we use the
4924 -- actual subtype object size, this is appropriate.
4926 -- For example, if we have
4928 -- subtype x is integer range 1 .. 200;
4929 -- for x'Object_Size use 8;
4931 -- Now the base type is signed, but objects of this type are bits
4932 -- unsigned, and doing an unsigned test of the range 1 to 200 is
4933 -- correct, even though a value greater than 127 looks signed to a
4934 -- signed comparison.
4936 elsif Is_Unsigned_Type (Ptyp) then
4937 if Esize (Ptyp) <= 32 then
4938 Btyp := RTE (RE_Unsigned_32);
4940 Btyp := RTE (RE_Unsigned_64);
4943 Rewrite (N, Make_Range_Test);
4948 if Esize (Ptyp) <= Esize (Standard_Integer) then
4949 Btyp := Standard_Integer;
4951 Btyp := Universal_Integer;
4954 Rewrite (N, Make_Range_Test);
4957 Analyze_And_Resolve (N, Standard_Boolean);
4958 Validity_Checks_On := Save_Validity_Checks_On;
4965 -- Value attribute is handled in separate unti Exp_Imgv
4967 when Attribute_Value =>
4968 Exp_Imgv.Expand_Value_Attribute (N);
4974 -- The processing for Value_Size shares the processing for Size
4980 -- The processing for Version shares the processing for Body_Version
4986 -- Wide_Image attribute is handled in separate unit Exp_Imgv
4988 when Attribute_Wide_Image =>
4989 Exp_Imgv.Expand_Wide_Image_Attribute (N);
4991 ---------------------
4992 -- Wide_Wide_Image --
4993 ---------------------
4995 -- Wide_Wide_Image attribute is handled in separate unit Exp_Imgv
4997 when Attribute_Wide_Wide_Image =>
4998 Exp_Imgv.Expand_Wide_Wide_Image_Attribute (N);
5004 -- We expand typ'Wide_Value (X) into
5007 -- (Wide_String_To_String (X, Wide_Character_Encoding_Method))
5009 -- Wide_String_To_String is a runtime function that converts its wide
5010 -- string argument to String, converting any non-translatable characters
5011 -- into appropriate escape sequences. This preserves the required
5012 -- semantics of Wide_Value in all cases, and results in a very simple
5013 -- implementation approach.
5015 -- Note: for this approach to be fully standard compliant for the cases
5016 -- where typ is Wide_Character and Wide_Wide_Character, the encoding
5017 -- method must cover the entire character range (e.g. UTF-8). But that
5018 -- is a reasonable requirement when dealing with encoded character
5019 -- sequences. Presumably if one of the restrictive encoding mechanisms
5020 -- is in use such as Shift-JIS, then characters that cannot be
5021 -- represented using this encoding will not appear in any case.
5023 when Attribute_Wide_Value => Wide_Value :
5026 Make_Attribute_Reference (Loc,
5028 Attribute_Name => Name_Value,
5030 Expressions => New_List (
5031 Make_Function_Call (Loc,
5033 New_Reference_To (RTE (RE_Wide_String_To_String), Loc),
5035 Parameter_Associations => New_List (
5036 Relocate_Node (First (Exprs)),
5037 Make_Integer_Literal (Loc,
5038 Intval => Int (Wide_Character_Encoding_Method)))))));
5040 Analyze_And_Resolve (N, Typ);
5043 ---------------------
5044 -- Wide_Wide_Value --
5045 ---------------------
5047 -- We expand typ'Wide_Value_Value (X) into
5050 -- (Wide_Wide_String_To_String (X, Wide_Character_Encoding_Method))
5052 -- Wide_Wide_String_To_String is a runtime function that converts its
5053 -- wide string argument to String, converting any non-translatable
5054 -- characters into appropriate escape sequences. This preserves the
5055 -- required semantics of Wide_Wide_Value in all cases, and results in a
5056 -- very simple implementation approach.
5058 -- It's not quite right where typ = Wide_Wide_Character, because the
5059 -- encoding method may not cover the whole character type ???
5061 when Attribute_Wide_Wide_Value => Wide_Wide_Value :
5064 Make_Attribute_Reference (Loc,
5066 Attribute_Name => Name_Value,
5068 Expressions => New_List (
5069 Make_Function_Call (Loc,
5071 New_Reference_To (RTE (RE_Wide_Wide_String_To_String), Loc),
5073 Parameter_Associations => New_List (
5074 Relocate_Node (First (Exprs)),
5075 Make_Integer_Literal (Loc,
5076 Intval => Int (Wide_Character_Encoding_Method)))))));
5078 Analyze_And_Resolve (N, Typ);
5079 end Wide_Wide_Value;
5081 ---------------------
5082 -- Wide_Wide_Width --
5083 ---------------------
5085 -- Wide_Wide_Width attribute is handled in separate unit Exp_Imgv
5087 when Attribute_Wide_Wide_Width =>
5088 Exp_Imgv.Expand_Width_Attribute (N, Wide_Wide);
5094 -- Wide_Width attribute is handled in separate unit Exp_Imgv
5096 when Attribute_Wide_Width =>
5097 Exp_Imgv.Expand_Width_Attribute (N, Wide);
5103 -- Width attribute is handled in separate unit Exp_Imgv
5105 when Attribute_Width =>
5106 Exp_Imgv.Expand_Width_Attribute (N, Normal);
5112 when Attribute_Write => Write : declare
5113 P_Type : constant Entity_Id := Entity (Pref);
5114 U_Type : constant Entity_Id := Underlying_Type (P_Type);
5122 -- If no underlying type, we have an error that will be diagnosed
5123 -- elsewhere, so here we just completely ignore the expansion.
5129 -- The simple case, if there is a TSS for Write, just call it
5131 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Write);
5133 if Present (Pname) then
5137 -- If there is a Stream_Convert pragma, use it, we rewrite
5139 -- sourcetyp'Output (stream, Item)
5143 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
5145 -- where strmwrite is the given Write function that converts an
5146 -- argument of type sourcetyp or a type acctyp, from which it is
5147 -- derived to type strmtyp. The conversion to acttyp is required
5148 -- for the derived case.
5150 Prag := Get_Stream_Convert_Pragma (P_Type);
5152 if Present (Prag) then
5154 Next (Next (First (Pragma_Argument_Associations (Prag))));
5155 Wfunc := Entity (Expression (Arg3));
5158 Make_Attribute_Reference (Loc,
5159 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
5160 Attribute_Name => Name_Output,
5161 Expressions => New_List (
5162 Relocate_Node (First (Exprs)),
5163 Make_Function_Call (Loc,
5164 Name => New_Occurrence_Of (Wfunc, Loc),
5165 Parameter_Associations => New_List (
5166 OK_Convert_To (Etype (First_Formal (Wfunc)),
5167 Relocate_Node (Next (First (Exprs)))))))));
5172 -- For elementary types, we call the W_xxx routine directly
5174 elsif Is_Elementary_Type (U_Type) then
5175 Rewrite (N, Build_Elementary_Write_Call (N));
5181 elsif Is_Array_Type (U_Type) then
5182 Build_Array_Write_Procedure (N, U_Type, Decl, Pname);
5183 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
5185 -- Tagged type case, use the primitive Write function. Note that
5186 -- this will dispatch in the class-wide case which is what we want
5188 elsif Is_Tagged_Type (U_Type) then
5189 Pname := Find_Prim_Op (U_Type, TSS_Stream_Write);
5191 -- All other record type cases, including protected records.
5192 -- The latter only arise for expander generated code for
5193 -- handling shared passive partition access.
5197 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
5199 -- Ada 2005 (AI-216): Program_Error is raised when executing
5200 -- the default implementation of the Write attribute of an
5201 -- Unchecked_Union type. However, if the 'Write reference is
5202 -- within the generated Output stream procedure, Write outputs
5203 -- the components, and the default values of the discriminant
5204 -- are streamed by the Output procedure itself.
5206 if Is_Unchecked_Union (Base_Type (U_Type))
5207 and not Is_TSS (Current_Scope, TSS_Stream_Output)
5210 Make_Raise_Program_Error (Loc,
5211 Reason => PE_Unchecked_Union_Restriction));
5214 if Has_Discriminants (U_Type)
5216 (Discriminant_Default_Value (First_Discriminant (U_Type)))
5218 Build_Mutable_Record_Write_Procedure
5219 (Loc, Base_Type (U_Type), Decl, Pname);
5221 Build_Record_Write_Procedure
5222 (Loc, Base_Type (U_Type), Decl, Pname);
5225 Insert_Action (N, Decl);
5229 -- If we fall through, Pname is the procedure to be called
5231 Rewrite_Stream_Proc_Call (Pname);
5234 -- Component_Size is handled by the back end, unless the component size
5235 -- is known at compile time, which is always true in the packed array
5236 -- case. It is important that the packed array case is handled in the
5237 -- front end (see Eval_Attribute) since the back end would otherwise get
5238 -- confused by the equivalent packed array type.
5240 when Attribute_Component_Size =>
5243 -- The following attributes are handled by the back end (except that
5244 -- static cases have already been evaluated during semantic processing,
5245 -- but in any case the back end should not count on this). The one bit
5246 -- of special processing required is that these attributes typically
5247 -- generate conditionals in the code, so we need to check the relevant
5250 when Attribute_Max |
5252 Check_Restriction (No_Implicit_Conditionals, N);
5254 -- The following attributes are handled by the back end (except that
5255 -- static cases have already been evaluated during semantic processing,
5256 -- but in any case the back end should not count on this).
5258 -- The back end also handles the non-class-wide cases of Size
5260 when Attribute_Bit_Order |
5261 Attribute_Code_Address |
5262 Attribute_Definite |
5263 Attribute_Null_Parameter |
5264 Attribute_Passed_By_Reference |
5265 Attribute_Pool_Address =>
5268 -- The following attributes are also handled by the back end, but return
5269 -- a universal integer result, so may need a conversion for checking
5270 -- that the result is in range.
5272 when Attribute_Aft |
5274 Attribute_Max_Size_In_Storage_Elements
5276 Apply_Universal_Integer_Attribute_Checks (N);
5278 -- The following attributes should not appear at this stage, since they
5279 -- have already been handled by the analyzer (and properly rewritten
5280 -- with corresponding values or entities to represent the right values)
5282 when Attribute_Abort_Signal |
5283 Attribute_Address_Size |
5286 Attribute_Compiler_Version |
5287 Attribute_Default_Bit_Order |
5294 Attribute_Fast_Math |
5295 Attribute_Has_Access_Values |
5296 Attribute_Has_Discriminants |
5297 Attribute_Has_Tagged_Values |
5299 Attribute_Machine_Emax |
5300 Attribute_Machine_Emin |
5301 Attribute_Machine_Mantissa |
5302 Attribute_Machine_Overflows |
5303 Attribute_Machine_Radix |
5304 Attribute_Machine_Rounds |
5305 Attribute_Maximum_Alignment |
5306 Attribute_Model_Emin |
5307 Attribute_Model_Epsilon |
5308 Attribute_Model_Mantissa |
5309 Attribute_Model_Small |
5311 Attribute_Partition_ID |
5313 Attribute_Safe_Emax |
5314 Attribute_Safe_First |
5315 Attribute_Safe_Large |
5316 Attribute_Safe_Last |
5317 Attribute_Safe_Small |
5319 Attribute_Signed_Zeros |
5321 Attribute_Storage_Unit |
5322 Attribute_Stub_Type |
5323 Attribute_Target_Name |
5324 Attribute_Type_Class |
5325 Attribute_Unconstrained_Array |
5326 Attribute_Universal_Literal_String |
5327 Attribute_Wchar_T_Size |
5328 Attribute_Word_Size =>
5330 raise Program_Error;
5332 -- The Asm_Input and Asm_Output attributes are not expanded at this
5333 -- stage, but will be eliminated in the expansion of the Asm call, see
5334 -- Exp_Intr for details. So the back end will never see these either.
5336 when Attribute_Asm_Input |
5337 Attribute_Asm_Output =>
5344 when RE_Not_Available =>
5346 end Expand_N_Attribute_Reference;
5348 ----------------------
5349 -- Expand_Pred_Succ --
5350 ----------------------
5352 -- For typ'Pred (exp), we generate the check
5354 -- [constraint_error when exp = typ'Base'First]
5356 -- Similarly, for typ'Succ (exp), we generate the check
5358 -- [constraint_error when exp = typ'Base'Last]
5360 -- These checks are not generated for modular types, since the proper
5361 -- semantics for Succ and Pred on modular types is to wrap, not raise CE.
5363 procedure Expand_Pred_Succ (N : Node_Id) is
5364 Loc : constant Source_Ptr := Sloc (N);
5368 if Attribute_Name (N) = Name_Pred then
5375 Make_Raise_Constraint_Error (Loc,
5379 Duplicate_Subexpr_Move_Checks (First (Expressions (N))),
5381 Make_Attribute_Reference (Loc,
5383 New_Reference_To (Base_Type (Etype (Prefix (N))), Loc),
5384 Attribute_Name => Cnam)),
5385 Reason => CE_Overflow_Check_Failed));
5386 end Expand_Pred_Succ;
5392 procedure Find_Fat_Info
5394 Fat_Type : out Entity_Id;
5395 Fat_Pkg : out RE_Id)
5397 Btyp : constant Entity_Id := Base_Type (T);
5398 Rtyp : constant Entity_Id := Root_Type (T);
5399 Digs : constant Nat := UI_To_Int (Digits_Value (Btyp));
5402 -- If the base type is VAX float, then get appropriate VAX float type
5404 if Vax_Float (Btyp) then
5407 Fat_Type := RTE (RE_Fat_VAX_F);
5408 Fat_Pkg := RE_Attr_VAX_F_Float;
5411 Fat_Type := RTE (RE_Fat_VAX_D);
5412 Fat_Pkg := RE_Attr_VAX_D_Float;
5415 Fat_Type := RTE (RE_Fat_VAX_G);
5416 Fat_Pkg := RE_Attr_VAX_G_Float;
5419 raise Program_Error;
5422 -- If root type is VAX float, this is the case where the library has
5423 -- been recompiled in VAX float mode, and we have an IEEE float type.
5424 -- This is when we use the special IEEE Fat packages.
5426 elsif Vax_Float (Rtyp) then
5429 Fat_Type := RTE (RE_Fat_IEEE_Short);
5430 Fat_Pkg := RE_Attr_IEEE_Short;
5433 Fat_Type := RTE (RE_Fat_IEEE_Long);
5434 Fat_Pkg := RE_Attr_IEEE_Long;
5437 raise Program_Error;
5440 -- If neither the base type nor the root type is VAX_Float then VAX
5441 -- float is out of the picture, and we can just use the root type.
5446 if Fat_Type = Standard_Short_Float then
5447 Fat_Pkg := RE_Attr_Short_Float;
5449 elsif Fat_Type = Standard_Float then
5450 Fat_Pkg := RE_Attr_Float;
5452 elsif Fat_Type = Standard_Long_Float then
5453 Fat_Pkg := RE_Attr_Long_Float;
5455 elsif Fat_Type = Standard_Long_Long_Float then
5456 Fat_Pkg := RE_Attr_Long_Long_Float;
5458 -- Universal real (which is its own root type) is treated as being
5459 -- equivalent to Standard.Long_Long_Float, since it is defined to
5460 -- have the same precision as the longest Float type.
5462 elsif Fat_Type = Universal_Real then
5463 Fat_Type := Standard_Long_Long_Float;
5464 Fat_Pkg := RE_Attr_Long_Long_Float;
5467 raise Program_Error;
5472 ----------------------------
5473 -- Find_Stream_Subprogram --
5474 ----------------------------
5476 function Find_Stream_Subprogram
5478 Nam : TSS_Name_Type) return Entity_Id
5480 Base_Typ : constant Entity_Id := Base_Type (Typ);
5481 Ent : constant Entity_Id := TSS (Typ, Nam);
5484 if Present (Ent) then
5488 -- Stream attributes for strings are expanded into library calls. The
5489 -- following checks are disabled when the run-time is not available or
5490 -- when compiling predefined types due to bootstrap issues. As a result,
5491 -- the compiler will generate in-place stream routines for string types
5492 -- that appear in GNAT's library, but will generate calls via rtsfind
5493 -- to library routines for user code.
5494 -- ??? For now, disable this code for JVM, since this generates a
5495 -- VerifyError exception at run-time on e.g. c330001.
5496 -- This is disabled for AAMP, to avoid making dependences on files not
5497 -- supported in the AAMP library (such as s-fileio.adb).
5499 if VM_Target /= JVM_Target
5500 and then not AAMP_On_Target
5502 not Is_Predefined_File_Name (Unit_File_Name (Current_Sem_Unit))
5504 -- String as defined in package Ada
5506 if Base_Typ = Standard_String then
5507 if Restriction_Active (No_Stream_Optimizations) then
5508 if Nam = TSS_Stream_Input then
5509 return RTE (RE_String_Input);
5511 elsif Nam = TSS_Stream_Output then
5512 return RTE (RE_String_Output);
5514 elsif Nam = TSS_Stream_Read then
5515 return RTE (RE_String_Read);
5517 else pragma Assert (Nam = TSS_Stream_Write);
5518 return RTE (RE_String_Write);
5522 if Nam = TSS_Stream_Input then
5523 return RTE (RE_String_Input_Blk_IO);
5525 elsif Nam = TSS_Stream_Output then
5526 return RTE (RE_String_Output_Blk_IO);
5528 elsif Nam = TSS_Stream_Read then
5529 return RTE (RE_String_Read_Blk_IO);
5531 else pragma Assert (Nam = TSS_Stream_Write);
5532 return RTE (RE_String_Write_Blk_IO);
5536 -- Wide_String as defined in package Ada
5538 elsif Base_Typ = Standard_Wide_String then
5539 if Restriction_Active (No_Stream_Optimizations) then
5540 if Nam = TSS_Stream_Input then
5541 return RTE (RE_Wide_String_Input);
5543 elsif Nam = TSS_Stream_Output then
5544 return RTE (RE_Wide_String_Output);
5546 elsif Nam = TSS_Stream_Read then
5547 return RTE (RE_Wide_String_Read);
5549 else pragma Assert (Nam = TSS_Stream_Write);
5550 return RTE (RE_Wide_String_Write);
5554 if Nam = TSS_Stream_Input then
5555 return RTE (RE_Wide_String_Input_Blk_IO);
5557 elsif Nam = TSS_Stream_Output then
5558 return RTE (RE_Wide_String_Output_Blk_IO);
5560 elsif Nam = TSS_Stream_Read then
5561 return RTE (RE_Wide_String_Read_Blk_IO);
5563 else pragma Assert (Nam = TSS_Stream_Write);
5564 return RTE (RE_Wide_String_Write_Blk_IO);
5568 -- Wide_Wide_String as defined in package Ada
5570 elsif Base_Typ = Standard_Wide_Wide_String then
5571 if Restriction_Active (No_Stream_Optimizations) then
5572 if Nam = TSS_Stream_Input then
5573 return RTE (RE_Wide_Wide_String_Input);
5575 elsif Nam = TSS_Stream_Output then
5576 return RTE (RE_Wide_Wide_String_Output);
5578 elsif Nam = TSS_Stream_Read then
5579 return RTE (RE_Wide_Wide_String_Read);
5581 else pragma Assert (Nam = TSS_Stream_Write);
5582 return RTE (RE_Wide_Wide_String_Write);
5586 if Nam = TSS_Stream_Input then
5587 return RTE (RE_Wide_Wide_String_Input_Blk_IO);
5589 elsif Nam = TSS_Stream_Output then
5590 return RTE (RE_Wide_Wide_String_Output_Blk_IO);
5592 elsif Nam = TSS_Stream_Read then
5593 return RTE (RE_Wide_Wide_String_Read_Blk_IO);
5595 else pragma Assert (Nam = TSS_Stream_Write);
5596 return RTE (RE_Wide_Wide_String_Write_Blk_IO);
5602 if Is_Tagged_Type (Typ)
5603 and then Is_Derived_Type (Typ)
5605 return Find_Prim_Op (Typ, Nam);
5607 return Find_Inherited_TSS (Typ, Nam);
5609 end Find_Stream_Subprogram;
5611 -----------------------
5612 -- Get_Index_Subtype --
5613 -----------------------
5615 function Get_Index_Subtype (N : Node_Id) return Node_Id is
5616 P_Type : Entity_Id := Etype (Prefix (N));
5621 if Is_Access_Type (P_Type) then
5622 P_Type := Designated_Type (P_Type);
5625 if No (Expressions (N)) then
5628 J := UI_To_Int (Expr_Value (First (Expressions (N))));
5631 Indx := First_Index (P_Type);
5637 return Etype (Indx);
5638 end Get_Index_Subtype;
5640 -------------------------------
5641 -- Get_Stream_Convert_Pragma --
5642 -------------------------------
5644 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id is
5649 -- Note: we cannot use Get_Rep_Pragma here because of the peculiarity
5650 -- that a stream convert pragma for a tagged type is not inherited from
5651 -- its parent. Probably what is wrong here is that it is basically
5652 -- incorrect to consider a stream convert pragma to be a representation
5653 -- pragma at all ???
5655 N := First_Rep_Item (Implementation_Base_Type (T));
5656 while Present (N) loop
5657 if Nkind (N) = N_Pragma
5658 and then Pragma_Name (N) = Name_Stream_Convert
5660 -- For tagged types this pragma is not inherited, so we
5661 -- must verify that it is defined for the given type and
5665 Entity (Expression (First (Pragma_Argument_Associations (N))));
5667 if not Is_Tagged_Type (T)
5669 or else (Is_Private_Type (Typ) and then T = Full_View (Typ))
5679 end Get_Stream_Convert_Pragma;
5681 ---------------------------------
5682 -- Is_Constrained_Packed_Array --
5683 ---------------------------------
5685 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean is
5686 Arr : Entity_Id := Typ;
5689 if Is_Access_Type (Arr) then
5690 Arr := Designated_Type (Arr);
5693 return Is_Array_Type (Arr)
5694 and then Is_Constrained (Arr)
5695 and then Present (Packed_Array_Type (Arr));
5696 end Is_Constrained_Packed_Array;
5698 ----------------------------------------
5699 -- Is_Inline_Floating_Point_Attribute --
5700 ----------------------------------------
5702 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean is
5703 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
5706 if Nkind (Parent (N)) /= N_Type_Conversion
5707 or else not Is_Integer_Type (Etype (Parent (N)))
5712 -- Should also support 'Machine_Rounding and 'Unbiased_Rounding, but
5713 -- required back end support has not been implemented yet ???
5715 return Id = Attribute_Truncation;
5716 end Is_Inline_Floating_Point_Attribute;
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