1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2007, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Exp_Atag; use Exp_Atag;
32 with Exp_Ch2; use Exp_Ch2;
33 with Exp_Ch9; use Exp_Ch9;
34 with Exp_Imgv; use Exp_Imgv;
35 with Exp_Pakd; use Exp_Pakd;
36 with Exp_Strm; use Exp_Strm;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Exp_VFpt; use Exp_VFpt;
40 with Freeze; use Freeze;
41 with Gnatvsn; use Gnatvsn;
42 with Itypes; use Itypes;
44 with Namet; use Namet;
45 with Nmake; use Nmake;
46 with Nlists; use Nlists;
48 with Restrict; use Restrict;
49 with Rident; use Rident;
50 with Rtsfind; use Rtsfind;
52 with Sem_Ch7; use Sem_Ch7;
53 with Sem_Ch8; use Sem_Ch8;
54 with Sem_Eval; use Sem_Eval;
55 with Sem_Res; use Sem_Res;
56 with Sem_Util; use Sem_Util;
57 with Sinfo; use Sinfo;
58 with Snames; use Snames;
59 with Stand; use Stand;
60 with Stringt; use Stringt;
61 with Targparm; use Targparm;
62 with Tbuild; use Tbuild;
63 with Ttypes; use Ttypes;
64 with Uintp; use Uintp;
65 with Uname; use Uname;
66 with Validsw; use Validsw;
68 package body Exp_Attr is
70 -----------------------
71 -- Local Subprograms --
72 -----------------------
74 procedure Compile_Stream_Body_In_Scope
79 -- The body for a stream subprogram may be generated outside of the scope
80 -- of the type. If the type is fully private, it may depend on the full
81 -- view of other types (e.g. indices) that are currently private as well.
82 -- We install the declarations of the package in which the type is declared
83 -- before compiling the body in what is its proper environment. The Check
84 -- parameter indicates if checks are to be suppressed for the stream body.
85 -- We suppress checks for array/record reads, since the rule is that these
86 -- are like assignments, out of range values due to uninitialized storage,
87 -- or other invalid values do NOT cause a Constraint_Error to be raised.
89 procedure Expand_Access_To_Protected_Op
94 -- An attribute reference to a protected subprogram is transformed into
95 -- a pair of pointers: one to the object, and one to the operations.
96 -- This expansion is performed for 'Access and for 'Unrestricted_Access.
98 procedure Expand_Fpt_Attribute
103 -- This procedure expands a call to a floating-point attribute function.
104 -- N is the attribute reference node, and Args is a list of arguments to
105 -- be passed to the function call. Pkg identifies the package containing
106 -- the appropriate instantiation of System.Fat_Gen. Float arguments in Args
107 -- have already been converted to the floating-point type for which Pkg was
108 -- instantiated. The Nam argument is the relevant attribute processing
109 -- routine to be called. This is the same as the attribute name, except in
110 -- the Unaligned_Valid case.
112 procedure Expand_Fpt_Attribute_R (N : Node_Id);
113 -- This procedure expands a call to a floating-point attribute function
114 -- that takes a single floating-point argument. The function to be called
115 -- is always the same as the attribute name.
117 procedure Expand_Fpt_Attribute_RI (N : Node_Id);
118 -- This procedure expands a call to a floating-point attribute function
119 -- that takes one floating-point argument and one integer argument. The
120 -- function to be called is always the same as the attribute name.
122 procedure Expand_Fpt_Attribute_RR (N : Node_Id);
123 -- This procedure expands a call to a floating-point attribute function
124 -- that takes two floating-point arguments. The function to be called
125 -- is always the same as the attribute name.
127 procedure Expand_Pred_Succ (N : Node_Id);
128 -- Handles expansion of Pred or Succ attributes for case of non-real
129 -- operand with overflow checking required.
131 function Get_Index_Subtype (N : Node_Id) return Entity_Id;
132 -- Used for Last, Last, and Length, when the prefix is an array type.
133 -- Obtains the corresponding index subtype.
135 procedure Find_Fat_Info
137 Fat_Type : out Entity_Id;
138 Fat_Pkg : out RE_Id);
139 -- Given a floating-point type T, identifies the package containing the
140 -- attributes for this type (returned in Fat_Pkg), and the corresponding
141 -- type for which this package was instantiated from Fat_Gen. Error if T
142 -- is not a floating-point type.
144 function Find_Stream_Subprogram
146 Nam : TSS_Name_Type) return Entity_Id;
147 -- Returns the stream-oriented subprogram attribute for Typ. For tagged
148 -- types, the corresponding primitive operation is looked up, else the
149 -- appropriate TSS from the type itself, or from its closest ancestor
150 -- defining it, is returned. In both cases, inheritance of representation
151 -- aspects is thus taken into account.
153 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id;
154 -- Given a type, find a corresponding stream convert pragma that applies to
155 -- the implementation base type of this type (Typ). If found, return the
156 -- pragma node, otherwise return Empty if no pragma is found.
158 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean;
159 -- Utility for array attributes, returns true on packed constrained
160 -- arrays, and on access to same.
162 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean;
163 -- Returns true iff the given node refers to an attribute call that
164 -- can be expanded directly by the back end and does not need front end
165 -- expansion. Typically used for rounding and truncation attributes that
166 -- appear directly inside a conversion to integer.
168 ----------------------------------
169 -- Compile_Stream_Body_In_Scope --
170 ----------------------------------
172 procedure Compile_Stream_Body_In_Scope
178 Installed : Boolean := False;
179 Scop : constant Entity_Id := Scope (Arr);
180 Curr : constant Entity_Id := Current_Scope;
184 and then not In_Open_Scopes (Scop)
185 and then Ekind (Scop) = E_Package
188 Install_Visible_Declarations (Scop);
189 Install_Private_Declarations (Scop);
192 -- The entities in the package are now visible, but the generated
193 -- stream entity must appear in the current scope (usually an
194 -- enclosing stream function) so that itypes all have their proper
201 Insert_Action (N, Decl);
203 Insert_Action (N, Decl, Suppress => All_Checks);
208 -- Remove extra copy of current scope, and package itself
211 End_Package_Scope (Scop);
213 end Compile_Stream_Body_In_Scope;
215 -----------------------------------
216 -- Expand_Access_To_Protected_Op --
217 -----------------------------------
219 procedure Expand_Access_To_Protected_Op
224 -- The value of the attribute_reference is a record containing two
225 -- fields: an access to the protected object, and an access to the
226 -- subprogram itself. The prefix is a selected component.
228 Loc : constant Source_Ptr := Sloc (N);
230 Btyp : constant Entity_Id := Base_Type (Typ);
232 E_T : constant Entity_Id := Equivalent_Type (Btyp);
233 Acc : constant Entity_Id :=
234 Etype (Next_Component (First_Component (E_T)));
238 function May_Be_External_Call return Boolean;
239 -- If the 'Access is to a local operation, but appears in a context
240 -- where it may lead to a call from outside the object, we must treat
241 -- this as an external call. Clearly we cannot tell without full
242 -- flow analysis, and a subsequent call that uses this 'Access may
243 -- lead to a bounded error (trying to seize locks twice, e.g.). For
244 -- now we treat 'Access as a potential external call if it is an actual
245 -- in a call to an outside subprogram.
247 --------------------------
248 -- May_Be_External_Call --
249 --------------------------
251 function May_Be_External_Call return Boolean is
254 if (Nkind (Parent (N)) = N_Procedure_Call_Statement
255 or else Nkind (Parent (N)) = N_Function_Call)
256 and then Is_Entity_Name (Name (Parent (N)))
258 Subp := Entity (Name (Parent (N)));
259 return not In_Open_Scopes (Scope (Subp));
263 end May_Be_External_Call;
265 -- Start of processing for Expand_Access_To_Protected_Op
268 -- Within the body of the protected type, the prefix
269 -- designates a local operation, and the object is the first
270 -- parameter of the corresponding protected body of the
271 -- current enclosing operation.
273 if Is_Entity_Name (Pref) then
274 pragma Assert (In_Open_Scopes (Scope (Entity (Pref))));
276 if May_Be_External_Call then
279 (External_Subprogram (Entity (Pref)), Loc);
283 (Protected_Body_Subprogram (Entity (Pref)), Loc);
286 Curr := Current_Scope;
287 while Scope (Curr) /= Scope (Entity (Pref)) loop
288 Curr := Scope (Curr);
291 -- In case of protected entries the first formal of its Protected_
292 -- Body_Subprogram is the address of the object.
294 if Ekind (Curr) = E_Entry then
298 (Protected_Body_Subprogram (Curr)), Loc);
300 -- In case of protected subprograms the first formal of its
301 -- Protected_Body_Subprogram is the object and we get its address.
305 Make_Attribute_Reference (Loc,
309 (Protected_Body_Subprogram (Curr)), Loc),
310 Attribute_Name => Name_Address);
313 -- Case where the prefix is not an entity name. Find the
314 -- version of the protected operation to be called from
315 -- outside the protected object.
321 (Entity (Selector_Name (Pref))), Loc);
324 Make_Attribute_Reference (Loc,
325 Prefix => Relocate_Node (Prefix (Pref)),
326 Attribute_Name => Name_Address);
334 Unchecked_Convert_To (Acc,
335 Make_Attribute_Reference (Loc,
337 Attribute_Name => Name_Address))));
341 Analyze_And_Resolve (N, E_T);
343 -- For subsequent analysis, the node must retain its type.
344 -- The backend will replace it with the equivalent type where
348 end Expand_Access_To_Protected_Op;
350 --------------------------
351 -- Expand_Fpt_Attribute --
352 --------------------------
354 procedure Expand_Fpt_Attribute
360 Loc : constant Source_Ptr := Sloc (N);
361 Typ : constant Entity_Id := Etype (N);
365 -- The function name is the selected component Attr_xxx.yyy where
366 -- Attr_xxx is the package name, and yyy is the argument Nam.
368 -- Note: it would be more usual to have separate RE entries for each
369 -- of the entities in the Fat packages, but first they have identical
370 -- names (so we would have to have lots of renaming declarations to
371 -- meet the normal RE rule of separate names for all runtime entities),
372 -- and second there would be an awful lot of them!
375 Make_Selected_Component (Loc,
376 Prefix => New_Reference_To (RTE (Pkg), Loc),
377 Selector_Name => Make_Identifier (Loc, Nam));
379 -- The generated call is given the provided set of parameters, and then
380 -- wrapped in a conversion which converts the result to the target type
381 -- We use the base type as the target because a range check may be
385 Unchecked_Convert_To (Base_Type (Etype (N)),
386 Make_Function_Call (Loc,
388 Parameter_Associations => Args)));
390 Analyze_And_Resolve (N, Typ);
391 end Expand_Fpt_Attribute;
393 ----------------------------
394 -- Expand_Fpt_Attribute_R --
395 ----------------------------
397 -- The single argument is converted to its root type to call the
398 -- appropriate runtime function, with the actual call being built
399 -- by Expand_Fpt_Attribute
401 procedure Expand_Fpt_Attribute_R (N : Node_Id) is
402 E1 : constant Node_Id := First (Expressions (N));
406 Find_Fat_Info (Etype (E1), Ftp, Pkg);
408 (N, Pkg, Attribute_Name (N),
409 New_List (Unchecked_Convert_To (Ftp, Relocate_Node (E1))));
410 end Expand_Fpt_Attribute_R;
412 -----------------------------
413 -- Expand_Fpt_Attribute_RI --
414 -----------------------------
416 -- The first argument is converted to its root type and the second
417 -- argument is converted to standard long long integer to call the
418 -- appropriate runtime function, with the actual call being built
419 -- by Expand_Fpt_Attribute
421 procedure Expand_Fpt_Attribute_RI (N : Node_Id) is
422 E1 : constant Node_Id := First (Expressions (N));
425 E2 : constant Node_Id := Next (E1);
427 Find_Fat_Info (Etype (E1), Ftp, Pkg);
429 (N, Pkg, Attribute_Name (N),
431 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
432 Unchecked_Convert_To (Standard_Integer, Relocate_Node (E2))));
433 end Expand_Fpt_Attribute_RI;
435 -----------------------------
436 -- Expand_Fpt_Attribute_RR --
437 -----------------------------
439 -- The two arguments are converted to their root types to call the
440 -- appropriate runtime function, with the actual call being built
441 -- by Expand_Fpt_Attribute
443 procedure Expand_Fpt_Attribute_RR (N : Node_Id) is
444 E1 : constant Node_Id := First (Expressions (N));
447 E2 : constant Node_Id := Next (E1);
449 Find_Fat_Info (Etype (E1), Ftp, Pkg);
451 (N, Pkg, Attribute_Name (N),
453 Unchecked_Convert_To (Ftp, Relocate_Node (E1)),
454 Unchecked_Convert_To (Ftp, Relocate_Node (E2))));
455 end Expand_Fpt_Attribute_RR;
457 ----------------------------------
458 -- Expand_N_Attribute_Reference --
459 ----------------------------------
461 procedure Expand_N_Attribute_Reference (N : Node_Id) is
462 Loc : constant Source_Ptr := Sloc (N);
463 Typ : constant Entity_Id := Etype (N);
464 Btyp : constant Entity_Id := Base_Type (Typ);
465 Pref : constant Node_Id := Prefix (N);
466 Exprs : constant List_Id := Expressions (N);
467 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
469 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id);
470 -- Rewrites a stream attribute for Read, Write or Output with the
471 -- procedure call. Pname is the entity for the procedure to call.
473 ------------------------------
474 -- Rewrite_Stream_Proc_Call --
475 ------------------------------
477 procedure Rewrite_Stream_Proc_Call (Pname : Entity_Id) is
478 Item : constant Node_Id := Next (First (Exprs));
479 Formal : constant Entity_Id := Next_Formal (First_Formal (Pname));
480 Formal_Typ : constant Entity_Id := Etype (Formal);
481 Is_Written : constant Boolean := (Ekind (Formal) /= E_In_Parameter);
484 -- The expansion depends on Item, the second actual, which is
485 -- the object being streamed in or out.
487 -- If the item is a component of a packed array type, and
488 -- a conversion is needed on exit, we introduce a temporary to
489 -- hold the value, because otherwise the packed reference will
490 -- not be properly expanded.
492 if Nkind (Item) = N_Indexed_Component
493 and then Is_Packed (Base_Type (Etype (Prefix (Item))))
494 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
498 Temp : constant Entity_Id :=
499 Make_Defining_Identifier
500 (Loc, New_Internal_Name ('V'));
506 Make_Object_Declaration (Loc,
507 Defining_Identifier => Temp,
509 New_Occurrence_Of (Formal_Typ, Loc));
510 Set_Etype (Temp, Formal_Typ);
513 Make_Assignment_Statement (Loc,
514 Name => New_Copy_Tree (Item),
517 (Etype (Item), New_Occurrence_Of (Temp, Loc)));
519 Rewrite (Item, New_Occurrence_Of (Temp, Loc));
523 Make_Procedure_Call_Statement (Loc,
524 Name => New_Occurrence_Of (Pname, Loc),
525 Parameter_Associations => Exprs),
528 Rewrite (N, Make_Null_Statement (Loc));
533 -- For the class-wide dispatching cases, and for cases in which
534 -- the base type of the second argument matches the base type of
535 -- the corresponding formal parameter (that is to say the stream
536 -- operation is not inherited), we are all set, and can use the
537 -- argument unchanged.
539 -- For all other cases we do an unchecked conversion of the second
540 -- parameter to the type of the formal of the procedure we are
541 -- calling. This deals with the private type cases, and with going
542 -- to the root type as required in elementary type case.
544 if not Is_Class_Wide_Type (Entity (Pref))
545 and then not Is_Class_Wide_Type (Etype (Item))
546 and then Base_Type (Etype (Item)) /= Base_Type (Formal_Typ)
549 Unchecked_Convert_To (Formal_Typ, Relocate_Node (Item)));
551 -- For untagged derived types set Assignment_OK, to prevent
552 -- copies from being created when the unchecked conversion
553 -- is expanded (which would happen in Remove_Side_Effects
554 -- if Expand_N_Unchecked_Conversion were allowed to call
555 -- Force_Evaluation). The copy could violate Ada semantics
556 -- in cases such as an actual that is an out parameter.
557 -- Note that this approach is also used in exp_ch7 for calls
558 -- to controlled type operations to prevent problems with
559 -- actuals wrapped in unchecked conversions.
561 if Is_Untagged_Derivation (Etype (Expression (Item))) then
562 Set_Assignment_OK (Item);
566 -- And now rewrite the call
569 Make_Procedure_Call_Statement (Loc,
570 Name => New_Occurrence_Of (Pname, Loc),
571 Parameter_Associations => Exprs));
574 end Rewrite_Stream_Proc_Call;
576 -- Start of processing for Expand_N_Attribute_Reference
579 -- Do required validity checking, if enabled. Do not apply check to
580 -- output parameters of an Asm instruction, since the value of this
581 -- is not set till after the attribute has been elaborated.
583 if Validity_Checks_On and then Validity_Check_Operands
584 and then Id /= Attribute_Asm_Output
589 Expr := First (Expressions (N));
590 while Present (Expr) loop
597 -- Remaining processing depends on specific attribute
605 when Attribute_Access |
606 Attribute_Unchecked_Access |
607 Attribute_Unrestricted_Access =>
609 Access_Cases : declare
610 Btyp_DDT : constant Entity_Id := Directly_Designated_Type (Btyp);
611 Ref_Object : constant Node_Id := Get_Referenced_Object (Pref);
614 if Is_Access_Protected_Subprogram_Type (Btyp) then
615 Expand_Access_To_Protected_Op (N, Pref, Typ);
617 -- If prefix is a type name, this is a reference to the current
618 -- instance of the type, within its initialization procedure.
620 elsif Is_Entity_Name (Pref)
621 and then Is_Type (Entity (Pref))
628 -- If the current instance name denotes a task type, then
629 -- the access attribute is rewritten to be the name of the
630 -- "_task" parameter associated with the task type's task
631 -- procedure. An unchecked conversion is applied to ensure
632 -- a type match in cases of expander-generated calls (e.g.
635 if Is_Task_Type (Entity (Pref)) then
637 First_Entity (Get_Task_Body_Procedure (Entity (Pref)));
638 while Present (Formal) loop
639 exit when Chars (Formal) = Name_uTask;
640 Next_Entity (Formal);
643 pragma Assert (Present (Formal));
646 Unchecked_Convert_To (Typ,
647 New_Occurrence_Of (Formal, Loc)));
650 -- The expression must appear in a default expression,
651 -- (which in the initialization procedure is the
652 -- right-hand side of an assignment), and not in a
653 -- discriminant constraint.
657 while Present (Par) loop
658 exit when Nkind (Par) = N_Assignment_Statement;
660 if Nkind (Par) = N_Component_Declaration then
667 if Present (Par) then
669 Make_Attribute_Reference (Loc,
670 Prefix => Make_Identifier (Loc, Name_uInit),
671 Attribute_Name => Attribute_Name (N)));
673 Analyze_And_Resolve (N, Typ);
678 -- If the prefix of an Access attribute is a dereference of an
679 -- access parameter (or a renaming of such a dereference) and
680 -- the context is a general access type (but not an anonymous
681 -- access type), then rewrite the attribute as a conversion of
682 -- the access parameter to the context access type. This will
683 -- result in an accessibility check being performed, if needed.
685 -- (X.all'Access => Acc_Type (X))
687 -- Note: Limit the expansion of an attribute applied to a
688 -- dereference of an access parameter so that it's only done
689 -- for 'Access. This fixes a problem with 'Unrestricted_Access
690 -- that leads to errors in the case where the attribute type
691 -- is access-to-variable and the access parameter is
692 -- access-to-constant. The conversion is only done to get
693 -- accessibility checks, so it makes sense to limit it to
696 elsif Nkind (Ref_Object) = N_Explicit_Dereference
697 and then Is_Entity_Name (Prefix (Ref_Object))
698 and then Ekind (Btyp) = E_General_Access_Type
699 and then Ekind (Entity (Prefix (Ref_Object))) in Formal_Kind
700 and then Ekind (Etype (Entity (Prefix (Ref_Object))))
701 = E_Anonymous_Access_Type
702 and then Present (Extra_Accessibility
703 (Entity (Prefix (Ref_Object))))
706 Convert_To (Typ, New_Copy_Tree (Prefix (Ref_Object))));
707 Analyze_And_Resolve (N, Typ);
709 -- Ada 2005 (AI-251): If the designated type is an interface we
710 -- add an implicit conversion to force the displacement of the
711 -- pointer to reference the secondary dispatch table.
713 elsif Is_Interface (Btyp_DDT)
714 and then (Comes_From_Source (N)
715 or else Comes_From_Source (Ref_Object)
716 or else (Nkind (Ref_Object) in N_Has_Chars
717 and then Chars (Ref_Object) = Name_uInit))
719 if Nkind (Ref_Object) /= N_Explicit_Dereference then
721 -- No implicit conversion required if types match
723 if Btyp_DDT /= Etype (Ref_Object) then
725 Convert_To (Directly_Designated_Type (Typ),
726 New_Copy_Tree (Prefix (N))));
728 Analyze_And_Resolve (Prefix (N),
729 Directly_Designated_Type (Typ));
732 -- When the object is an explicit dereference, convert the
733 -- dereference's prefix.
737 Obj_DDT : constant Entity_Id :=
739 (Directly_Designated_Type
740 (Etype (Prefix (Ref_Object))));
742 -- No implicit conversion required if designated types
745 if Obj_DDT /= Btyp_DDT
746 and then not (Is_Class_Wide_Type (Obj_DDT)
747 and then Etype (Obj_DDT) = Btyp_DDT)
751 New_Copy_Tree (Prefix (Ref_Object))));
752 Analyze_And_Resolve (N, Typ);
763 -- Transforms 'Adjacent into a call to the floating-point attribute
764 -- function Adjacent in Fat_xxx (where xxx is the root type)
766 when Attribute_Adjacent =>
767 Expand_Fpt_Attribute_RR (N);
773 when Attribute_Address => Address : declare
774 Task_Proc : Entity_Id;
777 -- If the prefix is a task or a task type, the useful address is that
778 -- of the procedure for the task body, i.e. the actual program unit.
779 -- We replace the original entity with that of the procedure.
781 if Is_Entity_Name (Pref)
782 and then Is_Task_Type (Entity (Pref))
784 Task_Proc := Next_Entity (Root_Type (Etype (Pref)));
786 while Present (Task_Proc) loop
787 exit when Ekind (Task_Proc) = E_Procedure
788 and then Etype (First_Formal (Task_Proc)) =
789 Corresponding_Record_Type (Etype (Pref));
790 Next_Entity (Task_Proc);
793 if Present (Task_Proc) then
794 Set_Entity (Pref, Task_Proc);
795 Set_Etype (Pref, Etype (Task_Proc));
798 -- Similarly, the address of a protected operation is the address
799 -- of the corresponding protected body, regardless of the protected
800 -- object from which it is selected.
802 elsif Nkind (Pref) = N_Selected_Component
803 and then Is_Subprogram (Entity (Selector_Name (Pref)))
804 and then Is_Protected_Type (Scope (Entity (Selector_Name (Pref))))
808 External_Subprogram (Entity (Selector_Name (Pref))), Loc));
810 elsif Nkind (Pref) = N_Explicit_Dereference
811 and then Ekind (Etype (Pref)) = E_Subprogram_Type
812 and then Convention (Etype (Pref)) = Convention_Protected
814 -- The prefix is be a dereference of an access_to_protected_
815 -- subprogram. The desired address is the second component of
816 -- the record that represents the access.
819 Addr : constant Entity_Id := Etype (N);
820 Ptr : constant Node_Id := Prefix (Pref);
821 T : constant Entity_Id :=
822 Equivalent_Type (Base_Type (Etype (Ptr)));
826 Unchecked_Convert_To (Addr,
827 Make_Selected_Component (Loc,
828 Prefix => Unchecked_Convert_To (T, Ptr),
829 Selector_Name => New_Occurrence_Of (
830 Next_Entity (First_Entity (T)), Loc))));
832 Analyze_And_Resolve (N, Addr);
835 -- Ada 2005 (AI-251): Class-wide interface objects are always
836 -- "displaced" to reference the tag associated with the interface
837 -- type. In order to obtain the real address of such objects we
838 -- generate a call to a run-time subprogram that returns the base
839 -- address of the object.
841 -- This processing is not needed in the VM case, where dispatching
842 -- issues are taken care of by the virtual machine.
844 elsif Is_Class_Wide_Type (Etype (Pref))
845 and then Is_Interface (Etype (Pref))
846 and then VM_Target = No_VM
847 and then not (Nkind (Pref) in N_Has_Entity
848 and then Is_Subprogram (Entity (Pref)))
851 Make_Function_Call (Loc,
852 Name => New_Reference_To (RTE (RE_Base_Address), Loc),
853 Parameter_Associations => New_List (
854 Relocate_Node (N))));
859 -- Deal with packed array reference, other cases are handled by gigi
861 if Involves_Packed_Array_Reference (Pref) then
862 Expand_Packed_Address_Reference (N);
870 when Attribute_Alignment => Alignment : declare
871 Ptyp : constant Entity_Id := Etype (Pref);
875 -- For class-wide types, X'Class'Alignment is transformed into a
876 -- direct reference to the Alignment of the class type, so that the
877 -- back end does not have to deal with the X'Class'Alignment
880 if Is_Entity_Name (Pref)
881 and then Is_Class_Wide_Type (Entity (Pref))
883 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
886 -- For x'Alignment applied to an object of a class wide type,
887 -- transform X'Alignment into a call to the predefined primitive
888 -- operation _Alignment applied to X.
890 elsif Is_Class_Wide_Type (Ptyp) then
892 -- No need to do anything else compiling under restriction
893 -- No_Dispatching_Calls. During the semantic analysis we
894 -- already notified such violation.
896 if Restriction_Active (No_Dispatching_Calls) then
901 Make_Function_Call (Loc,
902 Name => New_Reference_To
903 (Find_Prim_Op (Ptyp, Name_uAlignment), Loc),
904 Parameter_Associations => New_List (Pref));
906 if Typ /= Standard_Integer then
908 -- The context is a specific integer type with which the
909 -- original attribute was compatible. The function has a
910 -- specific type as well, so to preserve the compatibility
911 -- we must convert explicitly.
913 New_Node := Convert_To (Typ, New_Node);
916 Rewrite (N, New_Node);
917 Analyze_And_Resolve (N, Typ);
920 -- For all other cases, we just have to deal with the case of
921 -- the fact that the result can be universal.
924 Apply_Universal_Integer_Attribute_Checks (N);
932 when Attribute_AST_Entry => AST_Entry : declare
938 -- The reference to the entry or entry family
941 -- The index expression for an entry family reference, or
942 -- the Empty if Entry_Ref references a simple entry.
945 if Nkind (Pref) = N_Indexed_Component then
946 Entry_Ref := Prefix (Pref);
947 Index := First (Expressions (Pref));
953 -- Get expression for Task_Id and the entry entity
955 if Nkind (Entry_Ref) = N_Selected_Component then
957 Make_Attribute_Reference (Loc,
958 Attribute_Name => Name_Identity,
959 Prefix => Prefix (Entry_Ref));
961 Ttyp := Etype (Prefix (Entry_Ref));
962 Eent := Entity (Selector_Name (Entry_Ref));
966 Make_Function_Call (Loc,
967 Name => New_Occurrence_Of (RTE (RE_Current_Task), Loc));
969 Eent := Entity (Entry_Ref);
971 -- We have to find the enclosing task to get the task type
972 -- There must be one, since we already validated this earlier
974 Ttyp := Current_Scope;
975 while not Is_Task_Type (Ttyp) loop
976 Ttyp := Scope (Ttyp);
980 -- Now rewrite the attribute with a call to Create_AST_Handler
983 Make_Function_Call (Loc,
984 Name => New_Occurrence_Of (RTE (RE_Create_AST_Handler), Loc),
985 Parameter_Associations => New_List (
987 Entry_Index_Expression (Loc, Eent, Index, Ttyp))));
989 Analyze_And_Resolve (N, RTE (RE_AST_Handler));
996 -- We compute this if a component clause was present, otherwise
997 -- we leave the computation up to Gigi, since we don't know what
998 -- layout will be chosen.
1000 -- Note that the attribute can apply to a naked record component
1001 -- in generated code (i.e. the prefix is an identifier that
1002 -- references the component or discriminant entity).
1004 when Attribute_Bit_Position => Bit_Position :
1009 if Nkind (Pref) = N_Identifier then
1010 CE := Entity (Pref);
1012 CE := Entity (Selector_Name (Pref));
1015 if Known_Static_Component_Bit_Offset (CE) then
1017 Make_Integer_Literal (Loc,
1018 Intval => Component_Bit_Offset (CE)));
1019 Analyze_And_Resolve (N, Typ);
1022 Apply_Universal_Integer_Attribute_Checks (N);
1030 -- A reference to P'Body_Version or P'Version is expanded to
1033 -- pragma Import (C, Vnn, "uuuuT";
1035 -- Get_Version_String (Vnn)
1037 -- where uuuu is the unit name (dots replaced by double underscore)
1038 -- and T is B for the cases of Body_Version, or Version applied to a
1039 -- subprogram acting as its own spec, and S for Version applied to a
1040 -- subprogram spec or package. This sequence of code references the
1041 -- the unsigned constant created in the main program by the binder.
1043 -- A special exception occurs for Standard, where the string
1044 -- returned is a copy of the library string in gnatvsn.ads.
1046 when Attribute_Body_Version | Attribute_Version => Version : declare
1047 E : constant Entity_Id :=
1048 Make_Defining_Identifier (Loc, New_Internal_Name ('V'));
1053 -- If not library unit, get to containing library unit
1055 Pent := Entity (Pref);
1056 while Pent /= Standard_Standard
1057 and then Scope (Pent) /= Standard_Standard
1058 and then not Is_Child_Unit (Pent)
1060 Pent := Scope (Pent);
1063 -- Special case Standard and Standard.ASCII
1065 if Pent = Standard_Standard or else Pent = Standard_ASCII then
1067 Make_String_Literal (Loc,
1068 Strval => Verbose_Library_Version));
1073 -- Build required string constant
1075 Get_Name_String (Get_Unit_Name (Pent));
1078 for J in 1 .. Name_Len - 2 loop
1079 if Name_Buffer (J) = '.' then
1080 Store_String_Chars ("__");
1082 Store_String_Char (Get_Char_Code (Name_Buffer (J)));
1086 -- Case of subprogram acting as its own spec, always use body
1088 if Nkind (Declaration_Node (Pent)) in N_Subprogram_Specification
1089 and then Nkind (Parent (Declaration_Node (Pent))) =
1091 and then Acts_As_Spec (Parent (Declaration_Node (Pent)))
1093 Store_String_Chars ("B");
1095 -- Case of no body present, always use spec
1097 elsif not Unit_Requires_Body (Pent) then
1098 Store_String_Chars ("S");
1100 -- Otherwise use B for Body_Version, S for spec
1102 elsif Id = Attribute_Body_Version then
1103 Store_String_Chars ("B");
1105 Store_String_Chars ("S");
1109 Lib.Version_Referenced (S);
1111 -- Insert the object declaration
1113 Insert_Actions (N, New_List (
1114 Make_Object_Declaration (Loc,
1115 Defining_Identifier => E,
1116 Object_Definition =>
1117 New_Occurrence_Of (RTE (RE_Unsigned), Loc))));
1119 -- Set entity as imported with correct external name
1121 Set_Is_Imported (E);
1122 Set_Interface_Name (E, Make_String_Literal (Loc, S));
1124 -- Set entity as internal to ensure proper Sprint output of its
1125 -- implicit importation.
1127 Set_Is_Internal (E);
1129 -- And now rewrite original reference
1132 Make_Function_Call (Loc,
1133 Name => New_Reference_To (RTE (RE_Get_Version_String), Loc),
1134 Parameter_Associations => New_List (
1135 New_Occurrence_Of (E, Loc))));
1138 Analyze_And_Resolve (N, RTE (RE_Version_String));
1145 -- Transforms 'Ceiling into a call to the floating-point attribute
1146 -- function Ceiling in Fat_xxx (where xxx is the root type)
1148 when Attribute_Ceiling =>
1149 Expand_Fpt_Attribute_R (N);
1155 -- Transforms 'Callable attribute into a call to the Callable function
1157 when Attribute_Callable => Callable :
1159 -- We have an object of a task interface class-wide type as a prefix
1160 -- to Callable. Generate:
1162 -- callable (Task_Id (Pref._disp_get_task_id));
1164 if Ada_Version >= Ada_05
1165 and then Ekind (Etype (Pref)) = E_Class_Wide_Type
1166 and then Is_Interface (Etype (Pref))
1167 and then Is_Task_Interface (Etype (Pref))
1170 Make_Function_Call (Loc,
1172 New_Reference_To (RTE (RE_Callable), Loc),
1173 Parameter_Associations => New_List (
1174 Make_Unchecked_Type_Conversion (Loc,
1176 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
1178 Make_Selected_Component (Loc,
1180 New_Copy_Tree (Pref),
1182 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
1186 Build_Call_With_Task (Pref, RTE (RE_Callable)));
1189 Analyze_And_Resolve (N, Standard_Boolean);
1196 -- Transforms 'Caller attribute into a call to either the
1197 -- Task_Entry_Caller or the Protected_Entry_Caller function.
1199 when Attribute_Caller => Caller : declare
1200 Id_Kind : constant Entity_Id := RTE (RO_AT_Task_Id);
1201 Ent : constant Entity_Id := Entity (Pref);
1202 Conctype : constant Entity_Id := Scope (Ent);
1203 Nest_Depth : Integer := 0;
1210 if Is_Protected_Type (Conctype) then
1212 or else Restriction_Active (No_Entry_Queue) = False
1213 or else Number_Entries (Conctype) > 1
1217 (RTE (RE_Protected_Entry_Caller), Loc);
1221 (RTE (RE_Protected_Single_Entry_Caller), Loc);
1225 Unchecked_Convert_To (Id_Kind,
1226 Make_Function_Call (Loc,
1228 Parameter_Associations => New_List
1231 (Corresponding_Body (Parent (Conctype))), Loc)))));
1236 -- Determine the nesting depth of the E'Caller attribute, that
1237 -- is, how many accept statements are nested within the accept
1238 -- statement for E at the point of E'Caller. The runtime uses
1239 -- this depth to find the specified entry call.
1241 for J in reverse 0 .. Scope_Stack.Last loop
1242 S := Scope_Stack.Table (J).Entity;
1244 -- We should not reach the scope of the entry, as it should
1245 -- already have been checked in Sem_Attr that this attribute
1246 -- reference is within a matching accept statement.
1248 pragma Assert (S /= Conctype);
1253 elsif Is_Entry (S) then
1254 Nest_Depth := Nest_Depth + 1;
1259 Unchecked_Convert_To (Id_Kind,
1260 Make_Function_Call (Loc,
1261 Name => New_Reference_To (
1262 RTE (RE_Task_Entry_Caller), Loc),
1263 Parameter_Associations => New_List (
1264 Make_Integer_Literal (Loc,
1265 Intval => Int (Nest_Depth))))));
1268 Analyze_And_Resolve (N, Id_Kind);
1275 -- Transforms 'Compose into a call to the floating-point attribute
1276 -- function Compose in Fat_xxx (where xxx is the root type)
1278 -- Note: we strictly should have special code here to deal with the
1279 -- case of absurdly negative arguments (less than Integer'First)
1280 -- which will return a (signed) zero value, but it hardly seems
1281 -- worth the effort. Absurdly large positive arguments will raise
1282 -- constraint error which is fine.
1284 when Attribute_Compose =>
1285 Expand_Fpt_Attribute_RI (N);
1291 when Attribute_Constrained => Constrained : declare
1292 Formal_Ent : constant Entity_Id := Param_Entity (Pref);
1293 Typ : constant Entity_Id := Etype (Pref);
1295 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean;
1296 -- Ada 2005 (AI-363): Returns True if the object name Obj denotes a
1297 -- view of an aliased object whose subtype is constrained.
1299 ---------------------------------
1300 -- Is_Constrained_Aliased_View --
1301 ---------------------------------
1303 function Is_Constrained_Aliased_View (Obj : Node_Id) return Boolean is
1307 if Is_Entity_Name (Obj) then
1310 if Present (Renamed_Object (E)) then
1311 return Is_Constrained_Aliased_View (Renamed_Object (E));
1314 return Is_Aliased (E) and then Is_Constrained (Etype (E));
1318 return Is_Aliased_View (Obj)
1320 (Is_Constrained (Etype (Obj))
1321 or else (Nkind (Obj) = N_Explicit_Dereference
1323 not Has_Constrained_Partial_View
1324 (Base_Type (Etype (Obj)))));
1326 end Is_Constrained_Aliased_View;
1328 -- Start of processing for Constrained
1331 -- Reference to a parameter where the value is passed as an extra
1332 -- actual, corresponding to the extra formal referenced by the
1333 -- Extra_Constrained field of the corresponding formal. If this
1334 -- is an entry in-parameter, it is replaced by a constant renaming
1335 -- for which Extra_Constrained is never created.
1337 if Present (Formal_Ent)
1338 and then Ekind (Formal_Ent) /= E_Constant
1339 and then Present (Extra_Constrained (Formal_Ent))
1343 (Extra_Constrained (Formal_Ent), Sloc (N)));
1345 -- For variables with a Extra_Constrained field, we use the
1346 -- corresponding entity.
1348 elsif Nkind (Pref) = N_Identifier
1349 and then Ekind (Entity (Pref)) = E_Variable
1350 and then Present (Extra_Constrained (Entity (Pref)))
1354 (Extra_Constrained (Entity (Pref)), Sloc (N)));
1356 -- For all other entity names, we can tell at compile time
1358 elsif Is_Entity_Name (Pref) then
1360 Ent : constant Entity_Id := Entity (Pref);
1364 -- (RM J.4) obsolescent cases
1366 if Is_Type (Ent) then
1370 if Is_Private_Type (Ent) then
1371 Res := not Has_Discriminants (Ent)
1372 or else Is_Constrained (Ent);
1374 -- It not a private type, must be a generic actual type
1375 -- that corresponded to a private type. We know that this
1376 -- correspondence holds, since otherwise the reference
1377 -- within the generic template would have been illegal.
1380 if Is_Composite_Type (Underlying_Type (Ent)) then
1381 Res := Is_Constrained (Ent);
1387 -- If the prefix is not a variable or is aliased, then
1388 -- definitely true; if it's a formal parameter without
1389 -- an associated extra formal, then treat it as constrained.
1391 -- Ada 2005 (AI-363): An aliased prefix must be known to be
1392 -- constrained in order to set the attribute to True.
1394 elsif not Is_Variable (Pref)
1395 or else Present (Formal_Ent)
1396 or else (Ada_Version < Ada_05
1397 and then Is_Aliased_View (Pref))
1398 or else (Ada_Version >= Ada_05
1399 and then Is_Constrained_Aliased_View (Pref))
1403 -- Variable case, just look at type to see if it is
1404 -- constrained. Note that the one case where this is
1405 -- not accurate (the procedure formal case), has been
1408 -- We use the Underlying_Type here (and below) in case the
1409 -- type is private without discriminants, but the full type
1410 -- has discriminants. This case is illegal, but we generate it
1411 -- internally for passing to the Extra_Constrained parameter.
1414 Res := Is_Constrained (Underlying_Type (Etype (Ent)));
1418 New_Reference_To (Boolean_Literals (Res), Loc));
1421 -- Prefix is not an entity name. These are also cases where
1422 -- we can always tell at compile time by looking at the form
1423 -- and type of the prefix. If an explicit dereference of an
1424 -- object with constrained partial view, this is unconstrained
1425 -- (Ada 2005 AI-363).
1431 not Is_Variable (Pref)
1433 (Nkind (Pref) = N_Explicit_Dereference
1435 not Has_Constrained_Partial_View (Base_Type (Typ)))
1436 or else Is_Constrained (Underlying_Type (Typ))),
1440 Analyze_And_Resolve (N, Standard_Boolean);
1447 -- Transforms 'Copy_Sign into a call to the floating-point attribute
1448 -- function Copy_Sign in Fat_xxx (where xxx is the root type)
1450 when Attribute_Copy_Sign =>
1451 Expand_Fpt_Attribute_RR (N);
1457 -- Transforms 'Count attribute into a call to the Count function
1459 when Attribute_Count => Count :
1465 Conctyp : Entity_Id;
1468 -- If the prefix is a member of an entry family, retrieve both
1469 -- entry name and index. For a simple entry there is no index.
1471 if Nkind (Pref) = N_Indexed_Component then
1472 Entnam := Prefix (Pref);
1473 Index := First (Expressions (Pref));
1479 -- Find the concurrent type in which this attribute is referenced
1480 -- (there had better be one).
1482 Conctyp := Current_Scope;
1483 while not Is_Concurrent_Type (Conctyp) loop
1484 Conctyp := Scope (Conctyp);
1489 if Is_Protected_Type (Conctyp) then
1492 or else Restriction_Active (No_Entry_Queue) = False
1493 or else Number_Entries (Conctyp) > 1
1495 Name := New_Reference_To (RTE (RE_Protected_Count), Loc);
1498 Make_Function_Call (Loc,
1500 Parameter_Associations => New_List (
1503 Corresponding_Body (Parent (Conctyp))), Loc),
1504 Entry_Index_Expression (
1505 Loc, Entity (Entnam), Index, Scope (Entity (Entnam)))));
1507 Name := New_Reference_To (RTE (RE_Protected_Count_Entry), Loc);
1509 Call := Make_Function_Call (Loc,
1511 Parameter_Associations => New_List (
1514 Corresponding_Body (Parent (Conctyp))), Loc)));
1521 Make_Function_Call (Loc,
1522 Name => New_Reference_To (RTE (RE_Task_Count), Loc),
1523 Parameter_Associations => New_List (
1524 Entry_Index_Expression
1525 (Loc, Entity (Entnam), Index, Scope (Entity (Entnam)))));
1528 -- The call returns type Natural but the context is universal integer
1529 -- so any integer type is allowed. The attribute was already resolved
1530 -- so its Etype is the required result type. If the base type of the
1531 -- context type is other than Standard.Integer we put in a conversion
1532 -- to the required type. This can be a normal typed conversion since
1533 -- both input and output types of the conversion are integer types
1535 if Base_Type (Typ) /= Base_Type (Standard_Integer) then
1536 Rewrite (N, Convert_To (Typ, Call));
1541 Analyze_And_Resolve (N, Typ);
1548 -- This processing is shared by Elab_Spec
1550 -- What we do is to insert the following declarations
1553 -- pragma Import (C, enn, "name___elabb/s");
1555 -- and then the Elab_Body/Spec attribute is replaced by a reference
1556 -- to this defining identifier.
1558 when Attribute_Elab_Body |
1559 Attribute_Elab_Spec =>
1562 Ent : constant Entity_Id :=
1563 Make_Defining_Identifier (Loc,
1564 New_Internal_Name ('E'));
1568 procedure Make_Elab_String (Nod : Node_Id);
1569 -- Given Nod, an identifier, or a selected component, put the
1570 -- image into the current string literal, with double underline
1571 -- between components.
1573 ----------------------
1574 -- Make_Elab_String --
1575 ----------------------
1577 procedure Make_Elab_String (Nod : Node_Id) is
1579 if Nkind (Nod) = N_Selected_Component then
1580 Make_Elab_String (Prefix (Nod));
1584 Store_String_Char ('$');
1586 Store_String_Char ('.');
1588 Store_String_Char ('_');
1589 Store_String_Char ('_');
1592 Get_Name_String (Chars (Selector_Name (Nod)));
1595 pragma Assert (Nkind (Nod) = N_Identifier);
1596 Get_Name_String (Chars (Nod));
1599 Store_String_Chars (Name_Buffer (1 .. Name_Len));
1600 end Make_Elab_String;
1602 -- Start of processing for Elab_Body/Elab_Spec
1605 -- First we need to prepare the string literal for the name of
1606 -- the elaboration routine to be referenced.
1609 Make_Elab_String (Pref);
1611 if VM_Target = No_VM then
1612 Store_String_Chars ("___elab");
1613 Lang := Make_Identifier (Loc, Name_C);
1615 Store_String_Chars ("._elab");
1616 Lang := Make_Identifier (Loc, Name_Ada);
1619 if Id = Attribute_Elab_Body then
1620 Store_String_Char ('b');
1622 Store_String_Char ('s');
1627 Insert_Actions (N, New_List (
1628 Make_Subprogram_Declaration (Loc,
1630 Make_Procedure_Specification (Loc,
1631 Defining_Unit_Name => Ent)),
1634 Chars => Name_Import,
1635 Pragma_Argument_Associations => New_List (
1636 Make_Pragma_Argument_Association (Loc,
1637 Expression => Lang),
1639 Make_Pragma_Argument_Association (Loc,
1641 Make_Identifier (Loc, Chars (Ent))),
1643 Make_Pragma_Argument_Association (Loc,
1645 Make_String_Literal (Loc, Str))))));
1647 Set_Entity (N, Ent);
1648 Rewrite (N, New_Occurrence_Of (Ent, Loc));
1655 -- Elaborated is always True for preelaborated units, predefined
1656 -- units, pure units and units which have Elaborate_Body pragmas.
1657 -- These units have no elaboration entity.
1659 -- Note: The Elaborated attribute is never passed through to Gigi
1661 when Attribute_Elaborated => Elaborated : declare
1662 Ent : constant Entity_Id := Entity (Pref);
1665 if Present (Elaboration_Entity (Ent)) then
1667 New_Occurrence_Of (Elaboration_Entity (Ent), Loc));
1669 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
1677 when Attribute_Enum_Rep => Enum_Rep :
1679 -- X'Enum_Rep (Y) expands to
1683 -- This is simply a direct conversion from the enumeration type
1684 -- to the target integer type, which is treated by Gigi as a normal
1685 -- integer conversion, treating the enumeration type as an integer,
1686 -- which is exactly what we want! We set Conversion_OK to make sure
1687 -- that the analyzer does not complain about what otherwise might
1688 -- be an illegal conversion.
1690 if Is_Non_Empty_List (Exprs) then
1692 OK_Convert_To (Typ, Relocate_Node (First (Exprs))));
1694 -- X'Enum_Rep where X is an enumeration literal is replaced by
1695 -- the literal value.
1697 elsif Ekind (Entity (Pref)) = E_Enumeration_Literal then
1699 Make_Integer_Literal (Loc, Enumeration_Rep (Entity (Pref))));
1701 -- If this is a renaming of a literal, recover the representation
1704 elsif Ekind (Entity (Pref)) = E_Constant
1705 and then Present (Renamed_Object (Entity (Pref)))
1707 Ekind (Entity (Renamed_Object (Entity (Pref))))
1708 = E_Enumeration_Literal
1711 Make_Integer_Literal (Loc,
1712 Enumeration_Rep (Entity (Renamed_Object (Entity (Pref))))));
1714 -- X'Enum_Rep where X is an object does a direct unchecked conversion
1715 -- of the object value, as described for the type case above.
1719 OK_Convert_To (Typ, Relocate_Node (Pref)));
1723 Analyze_And_Resolve (N, Typ);
1731 -- Transforms 'Exponent into a call to the floating-point attribute
1732 -- function Exponent in Fat_xxx (where xxx is the root type)
1734 when Attribute_Exponent =>
1735 Expand_Fpt_Attribute_R (N);
1741 -- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag)
1743 when Attribute_External_Tag => External_Tag :
1746 Make_Function_Call (Loc,
1747 Name => New_Reference_To (RTE (RE_External_Tag), Loc),
1748 Parameter_Associations => New_List (
1749 Make_Attribute_Reference (Loc,
1750 Attribute_Name => Name_Tag,
1751 Prefix => Prefix (N)))));
1753 Analyze_And_Resolve (N, Standard_String);
1760 when Attribute_First => declare
1761 Ptyp : constant Entity_Id := Etype (Pref);
1764 -- If the prefix type is a constrained packed array type which
1765 -- already has a Packed_Array_Type representation defined, then
1766 -- replace this attribute with a direct reference to 'First of the
1767 -- appropriate index subtype (since otherwise Gigi will try to give
1768 -- us the value of 'First for this implementation type).
1770 if Is_Constrained_Packed_Array (Ptyp) then
1772 Make_Attribute_Reference (Loc,
1773 Attribute_Name => Name_First,
1774 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
1775 Analyze_And_Resolve (N, Typ);
1777 elsif Is_Access_Type (Ptyp) then
1778 Apply_Access_Check (N);
1786 -- We compute this if a component clause was present, otherwise
1787 -- we leave the computation up to Gigi, since we don't know what
1788 -- layout will be chosen.
1790 when Attribute_First_Bit => First_Bit :
1792 CE : constant Entity_Id := Entity (Selector_Name (Pref));
1795 if Known_Static_Component_Bit_Offset (CE) then
1797 Make_Integer_Literal (Loc,
1798 Component_Bit_Offset (CE) mod System_Storage_Unit));
1800 Analyze_And_Resolve (N, Typ);
1803 Apply_Universal_Integer_Attribute_Checks (N);
1813 -- fixtype'Fixed_Value (integer-value)
1817 -- fixtype(integer-value)
1819 -- we do all the required analysis of the conversion here, because
1820 -- we do not want this to go through the fixed-point conversion
1821 -- circuits. Note that gigi always treats fixed-point as equivalent
1822 -- to the corresponding integer type anyway.
1824 when Attribute_Fixed_Value => Fixed_Value :
1827 Make_Type_Conversion (Loc,
1828 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
1829 Expression => Relocate_Node (First (Exprs))));
1830 Set_Etype (N, Entity (Pref));
1833 -- Note: it might appear that a properly analyzed unchecked conversion
1834 -- would be just fine here, but that's not the case, since the full
1835 -- range checks performed by the following call are critical!
1837 Apply_Type_Conversion_Checks (N);
1844 -- Transforms 'Floor into a call to the floating-point attribute
1845 -- function Floor in Fat_xxx (where xxx is the root type)
1847 when Attribute_Floor =>
1848 Expand_Fpt_Attribute_R (N);
1854 -- For the fixed-point type Typ:
1860 -- Result_Type (System.Fore (Universal_Real (Type'First)),
1861 -- Universal_Real (Type'Last))
1863 -- Note that we know that the type is a non-static subtype, or Fore
1864 -- would have itself been computed dynamically in Eval_Attribute.
1866 when Attribute_Fore => Fore :
1868 Ptyp : constant Entity_Id := Etype (Pref);
1873 Make_Function_Call (Loc,
1874 Name => New_Reference_To (RTE (RE_Fore), Loc),
1876 Parameter_Associations => New_List (
1877 Convert_To (Universal_Real,
1878 Make_Attribute_Reference (Loc,
1879 Prefix => New_Reference_To (Ptyp, Loc),
1880 Attribute_Name => Name_First)),
1882 Convert_To (Universal_Real,
1883 Make_Attribute_Reference (Loc,
1884 Prefix => New_Reference_To (Ptyp, Loc),
1885 Attribute_Name => Name_Last))))));
1887 Analyze_And_Resolve (N, Typ);
1894 -- Transforms 'Fraction into a call to the floating-point attribute
1895 -- function Fraction in Fat_xxx (where xxx is the root type)
1897 when Attribute_Fraction =>
1898 Expand_Fpt_Attribute_R (N);
1904 -- For an exception returns a reference to the exception data:
1905 -- Exception_Id!(Prefix'Reference)
1907 -- For a task it returns a reference to the _task_id component of
1908 -- corresponding record:
1910 -- taskV!(Prefix)._Task_Id, converted to the type Task_Id defined
1912 -- in Ada.Task_Identification
1914 when Attribute_Identity => Identity : declare
1915 Id_Kind : Entity_Id;
1918 if Etype (Pref) = Standard_Exception_Type then
1919 Id_Kind := RTE (RE_Exception_Id);
1921 if Present (Renamed_Object (Entity (Pref))) then
1922 Set_Entity (Pref, Renamed_Object (Entity (Pref)));
1926 Unchecked_Convert_To (Id_Kind, Make_Reference (Loc, Pref)));
1928 Id_Kind := RTE (RO_AT_Task_Id);
1930 -- If the prefix is a task interface, the Task_Id is obtained
1931 -- dynamically through a dispatching call, as for other task
1932 -- attributes applied to interfaces.
1934 if Ada_Version >= Ada_05
1935 and then Ekind (Etype (Pref)) = E_Class_Wide_Type
1936 and then Is_Interface (Etype (Pref))
1937 and then Is_Task_Interface (Etype (Pref))
1940 Unchecked_Convert_To (Id_Kind,
1941 Make_Selected_Component (Loc,
1943 New_Copy_Tree (Pref),
1945 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))));
1949 Unchecked_Convert_To (Id_Kind, Concurrent_Ref (Pref)));
1953 Analyze_And_Resolve (N, Id_Kind);
1960 -- Image attribute is handled in separate unit Exp_Imgv
1962 when Attribute_Image =>
1963 Exp_Imgv.Expand_Image_Attribute (N);
1969 -- X'Img is expanded to typ'Image (X), where typ is the type of X
1971 when Attribute_Img => Img :
1974 Make_Attribute_Reference (Loc,
1975 Prefix => New_Reference_To (Etype (Pref), Loc),
1976 Attribute_Name => Name_Image,
1977 Expressions => New_List (Relocate_Node (Pref))));
1979 Analyze_And_Resolve (N, Standard_String);
1986 when Attribute_Input => Input : declare
1987 P_Type : constant Entity_Id := Entity (Pref);
1988 B_Type : constant Entity_Id := Base_Type (P_Type);
1989 U_Type : constant Entity_Id := Underlying_Type (P_Type);
1990 Strm : constant Node_Id := First (Exprs);
1998 Cntrl : Node_Id := Empty;
1999 -- Value for controlling argument in call. Always Empty except in
2000 -- the dispatching (class-wide type) case, where it is a reference
2001 -- to the dummy object initialized to the right internal tag.
2003 procedure Freeze_Stream_Subprogram (F : Entity_Id);
2004 -- The expansion of the attribute reference may generate a call to
2005 -- a user-defined stream subprogram that is frozen by the call. This
2006 -- can lead to access-before-elaboration problem if the reference
2007 -- appears in an object declaration and the subprogram body has not
2008 -- been seen. The freezing of the subprogram requires special code
2009 -- because it appears in an expanded context where expressions do
2010 -- not freeze their constituents.
2012 ------------------------------
2013 -- Freeze_Stream_Subprogram --
2014 ------------------------------
2016 procedure Freeze_Stream_Subprogram (F : Entity_Id) is
2017 Decl : constant Node_Id := Unit_Declaration_Node (F);
2021 -- If this is user-defined subprogram, the corresponding
2022 -- stream function appears as a renaming-as-body, and the
2023 -- user subprogram must be retrieved by tree traversal.
2026 and then Nkind (Decl) = N_Subprogram_Declaration
2027 and then Present (Corresponding_Body (Decl))
2029 Bod := Corresponding_Body (Decl);
2031 if Nkind (Unit_Declaration_Node (Bod)) =
2032 N_Subprogram_Renaming_Declaration
2034 Set_Is_Frozen (Entity (Name (Unit_Declaration_Node (Bod))));
2037 end Freeze_Stream_Subprogram;
2039 -- Start of processing for Input
2042 -- If no underlying type, we have an error that will be diagnosed
2043 -- elsewhere, so here we just completely ignore the expansion.
2049 -- If there is a TSS for Input, just call it
2051 Fname := Find_Stream_Subprogram (P_Type, TSS_Stream_Input);
2053 if Present (Fname) then
2057 -- If there is a Stream_Convert pragma, use it, we rewrite
2059 -- sourcetyp'Input (stream)
2063 -- sourcetyp (streamread (strmtyp'Input (stream)));
2065 -- where stmrearead is the given Read function that converts
2066 -- an argument of type strmtyp to type sourcetyp or a type
2067 -- from which it is derived. The extra conversion is required
2068 -- for the derived case.
2070 Prag := Get_Stream_Convert_Pragma (P_Type);
2072 if Present (Prag) then
2073 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
2074 Rfunc := Entity (Expression (Arg2));
2078 Make_Function_Call (Loc,
2079 Name => New_Occurrence_Of (Rfunc, Loc),
2080 Parameter_Associations => New_List (
2081 Make_Attribute_Reference (Loc,
2084 (Etype (First_Formal (Rfunc)), Loc),
2085 Attribute_Name => Name_Input,
2086 Expressions => Exprs)))));
2088 Analyze_And_Resolve (N, B_Type);
2093 elsif Is_Elementary_Type (U_Type) then
2095 -- A special case arises if we have a defined _Read routine,
2096 -- since in this case we are required to call this routine.
2098 if Present (TSS (Base_Type (U_Type), TSS_Stream_Read)) then
2099 Build_Record_Or_Elementary_Input_Function
2100 (Loc, U_Type, Decl, Fname);
2101 Insert_Action (N, Decl);
2103 -- For normal cases, we call the I_xxx routine directly
2106 Rewrite (N, Build_Elementary_Input_Call (N));
2107 Analyze_And_Resolve (N, P_Type);
2113 elsif Is_Array_Type (U_Type) then
2114 Build_Array_Input_Function (Loc, U_Type, Decl, Fname);
2115 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
2117 -- Dispatching case with class-wide type
2119 elsif Is_Class_Wide_Type (P_Type) then
2121 -- No need to do anything else compiling under restriction
2122 -- No_Dispatching_Calls. During the semantic analysis we
2123 -- already notified such violation.
2125 if Restriction_Active (No_Dispatching_Calls) then
2130 Rtyp : constant Entity_Id := Root_Type (P_Type);
2135 -- Read the internal tag (RM 13.13.2(34)) and use it to
2136 -- initialize a dummy tag object:
2138 -- Dnn : Ada.Tags.Tag
2139 -- := Descendant_Tag (String'Input (Strm), P_Type);
2141 -- This dummy object is used only to provide a controlling
2142 -- argument for the eventual _Input call. Descendant_Tag is
2143 -- called rather than Internal_Tag to ensure that we have a
2144 -- tag for a type that is descended from the prefix type and
2145 -- declared at the same accessibility level (the exception
2146 -- Tag_Error will be raised otherwise). The level check is
2147 -- required for Ada 2005 because tagged types can be
2148 -- extended in nested scopes (AI-344).
2151 Make_Defining_Identifier (Loc,
2152 Chars => New_Internal_Name ('D'));
2155 Make_Object_Declaration (Loc,
2156 Defining_Identifier => Dnn,
2157 Object_Definition =>
2158 New_Occurrence_Of (RTE (RE_Tag), Loc),
2160 Make_Function_Call (Loc,
2162 New_Occurrence_Of (RTE (RE_Descendant_Tag), Loc),
2163 Parameter_Associations => New_List (
2164 Make_Attribute_Reference (Loc,
2166 New_Occurrence_Of (Standard_String, Loc),
2167 Attribute_Name => Name_Input,
2168 Expressions => New_List (
2170 (Duplicate_Subexpr (Strm)))),
2171 Make_Attribute_Reference (Loc,
2172 Prefix => New_Reference_To (P_Type, Loc),
2173 Attribute_Name => Name_Tag))));
2175 Insert_Action (N, Decl);
2177 -- Now we need to get the entity for the call, and construct
2178 -- a function call node, where we preset a reference to Dnn
2179 -- as the controlling argument (doing an unchecked convert
2180 -- to the class-wide tagged type to make it look like a real
2183 Fname := Find_Prim_Op (Rtyp, TSS_Stream_Input);
2184 Cntrl := Unchecked_Convert_To (P_Type,
2185 New_Occurrence_Of (Dnn, Loc));
2186 Set_Etype (Cntrl, P_Type);
2187 Set_Parent (Cntrl, N);
2190 -- For tagged types, use the primitive Input function
2192 elsif Is_Tagged_Type (U_Type) then
2193 Fname := Find_Prim_Op (U_Type, TSS_Stream_Input);
2195 -- All other record type cases, including protected records. The
2196 -- latter only arise for expander generated code for handling
2197 -- shared passive partition access.
2201 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
2203 -- Ada 2005 (AI-216): Program_Error is raised when executing
2204 -- the default implementation of the Input attribute of an
2205 -- unchecked union type if the type lacks default discriminant
2208 if Is_Unchecked_Union (Base_Type (U_Type))
2209 and then No (Discriminant_Constraint (U_Type))
2212 Make_Raise_Program_Error (Loc,
2213 Reason => PE_Unchecked_Union_Restriction));
2218 Build_Record_Or_Elementary_Input_Function
2219 (Loc, Base_Type (U_Type), Decl, Fname);
2220 Insert_Action (N, Decl);
2222 if Nkind (Parent (N)) = N_Object_Declaration
2223 and then Is_Record_Type (U_Type)
2225 -- The stream function may contain calls to user-defined
2226 -- Read procedures for individual components.
2233 Comp := First_Component (U_Type);
2234 while Present (Comp) loop
2236 Find_Stream_Subprogram
2237 (Etype (Comp), TSS_Stream_Read);
2239 if Present (Func) then
2240 Freeze_Stream_Subprogram (Func);
2243 Next_Component (Comp);
2250 -- If we fall through, Fname is the function to be called. The result
2251 -- is obtained by calling the appropriate function, then converting
2252 -- the result. The conversion does a subtype check.
2255 Make_Function_Call (Loc,
2256 Name => New_Occurrence_Of (Fname, Loc),
2257 Parameter_Associations => New_List (
2258 Relocate_Node (Strm)));
2260 Set_Controlling_Argument (Call, Cntrl);
2261 Rewrite (N, Unchecked_Convert_To (P_Type, Call));
2262 Analyze_And_Resolve (N, P_Type);
2264 if Nkind (Parent (N)) = N_Object_Declaration then
2265 Freeze_Stream_Subprogram (Fname);
2275 -- inttype'Fixed_Value (fixed-value)
2279 -- inttype(integer-value))
2281 -- we do all the required analysis of the conversion here, because
2282 -- we do not want this to go through the fixed-point conversion
2283 -- circuits. Note that gigi always treats fixed-point as equivalent
2284 -- to the corresponding integer type anyway.
2286 when Attribute_Integer_Value => Integer_Value :
2289 Make_Type_Conversion (Loc,
2290 Subtype_Mark => New_Occurrence_Of (Entity (Pref), Loc),
2291 Expression => Relocate_Node (First (Exprs))));
2292 Set_Etype (N, Entity (Pref));
2295 -- Note: it might appear that a properly analyzed unchecked conversion
2296 -- would be just fine here, but that's not the case, since the full
2297 -- range checks performed by the following call are critical!
2299 Apply_Type_Conversion_Checks (N);
2306 when Attribute_Last => declare
2307 Ptyp : constant Entity_Id := Etype (Pref);
2310 -- If the prefix type is a constrained packed array type which
2311 -- already has a Packed_Array_Type representation defined, then
2312 -- replace this attribute with a direct reference to 'Last of the
2313 -- appropriate index subtype (since otherwise Gigi will try to give
2314 -- us the value of 'Last for this implementation type).
2316 if Is_Constrained_Packed_Array (Ptyp) then
2318 Make_Attribute_Reference (Loc,
2319 Attribute_Name => Name_Last,
2320 Prefix => New_Reference_To (Get_Index_Subtype (N), Loc)));
2321 Analyze_And_Resolve (N, Typ);
2323 elsif Is_Access_Type (Ptyp) then
2324 Apply_Access_Check (N);
2332 -- We compute this if a component clause was present, otherwise
2333 -- we leave the computation up to Gigi, since we don't know what
2334 -- layout will be chosen.
2336 when Attribute_Last_Bit => Last_Bit :
2338 CE : constant Entity_Id := Entity (Selector_Name (Pref));
2341 if Known_Static_Component_Bit_Offset (CE)
2342 and then Known_Static_Esize (CE)
2345 Make_Integer_Literal (Loc,
2346 Intval => (Component_Bit_Offset (CE) mod System_Storage_Unit)
2349 Analyze_And_Resolve (N, Typ);
2352 Apply_Universal_Integer_Attribute_Checks (N);
2360 -- Transforms 'Leading_Part into a call to the floating-point attribute
2361 -- function Leading_Part in Fat_xxx (where xxx is the root type)
2363 -- Note: strictly, we should have special case code to deal with
2364 -- absurdly large positive arguments (greater than Integer'Last), which
2365 -- result in returning the first argument unchanged, but it hardly seems
2366 -- worth the effort. We raise constraint error for absurdly negative
2367 -- arguments which is fine.
2369 when Attribute_Leading_Part =>
2370 Expand_Fpt_Attribute_RI (N);
2376 when Attribute_Length => declare
2377 Ptyp : constant Entity_Id := Etype (Pref);
2382 -- Processing for packed array types
2384 if Is_Array_Type (Ptyp) and then Is_Packed (Ptyp) then
2385 Ityp := Get_Index_Subtype (N);
2387 -- If the index type, Ityp, is an enumeration type with
2388 -- holes, then we calculate X'Length explicitly using
2391 -- (0, Ityp'Pos (X'Last (N)) -
2392 -- Ityp'Pos (X'First (N)) + 1);
2394 -- Since the bounds in the template are the representation
2395 -- values and gigi would get the wrong value.
2397 if Is_Enumeration_Type (Ityp)
2398 and then Present (Enum_Pos_To_Rep (Base_Type (Ityp)))
2403 Xnum := Expr_Value (First (Expressions (N)));
2407 Make_Attribute_Reference (Loc,
2408 Prefix => New_Occurrence_Of (Typ, Loc),
2409 Attribute_Name => Name_Max,
2410 Expressions => New_List
2411 (Make_Integer_Literal (Loc, 0),
2415 Make_Op_Subtract (Loc,
2417 Make_Attribute_Reference (Loc,
2418 Prefix => New_Occurrence_Of (Ityp, Loc),
2419 Attribute_Name => Name_Pos,
2421 Expressions => New_List (
2422 Make_Attribute_Reference (Loc,
2423 Prefix => Duplicate_Subexpr (Pref),
2424 Attribute_Name => Name_Last,
2425 Expressions => New_List (
2426 Make_Integer_Literal (Loc, Xnum))))),
2429 Make_Attribute_Reference (Loc,
2430 Prefix => New_Occurrence_Of (Ityp, Loc),
2431 Attribute_Name => Name_Pos,
2433 Expressions => New_List (
2434 Make_Attribute_Reference (Loc,
2436 Duplicate_Subexpr_No_Checks (Pref),
2437 Attribute_Name => Name_First,
2438 Expressions => New_List (
2439 Make_Integer_Literal (Loc, Xnum)))))),
2441 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
2443 Analyze_And_Resolve (N, Typ, Suppress => All_Checks);
2446 -- If the prefix type is a constrained packed array type which
2447 -- already has a Packed_Array_Type representation defined, then
2448 -- replace this attribute with a direct reference to 'Range_Length
2449 -- of the appropriate index subtype (since otherwise Gigi will try
2450 -- to give us the value of 'Length for this implementation type).
2452 elsif Is_Constrained (Ptyp) then
2454 Make_Attribute_Reference (Loc,
2455 Attribute_Name => Name_Range_Length,
2456 Prefix => New_Reference_To (Ityp, Loc)));
2457 Analyze_And_Resolve (N, Typ);
2460 -- If we have a packed array that is not bit packed, which was
2464 elsif Is_Access_Type (Ptyp) then
2465 Apply_Access_Check (N);
2467 -- If the designated type is a packed array type, then we
2468 -- convert the reference to:
2471 -- xtyp'Pos (Pref'Last (Expr)) -
2472 -- xtyp'Pos (Pref'First (Expr)));
2474 -- This is a bit complex, but it is the easiest thing to do
2475 -- that works in all cases including enum types with holes
2476 -- xtyp here is the appropriate index type.
2479 Dtyp : constant Entity_Id := Designated_Type (Ptyp);
2483 if Is_Array_Type (Dtyp) and then Is_Packed (Dtyp) then
2484 Xtyp := Get_Index_Subtype (N);
2487 Make_Attribute_Reference (Loc,
2488 Prefix => New_Occurrence_Of (Typ, Loc),
2489 Attribute_Name => Name_Max,
2490 Expressions => New_List (
2491 Make_Integer_Literal (Loc, 0),
2494 Make_Integer_Literal (Loc, 1),
2495 Make_Op_Subtract (Loc,
2497 Make_Attribute_Reference (Loc,
2498 Prefix => New_Occurrence_Of (Xtyp, Loc),
2499 Attribute_Name => Name_Pos,
2500 Expressions => New_List (
2501 Make_Attribute_Reference (Loc,
2502 Prefix => Duplicate_Subexpr (Pref),
2503 Attribute_Name => Name_Last,
2505 New_Copy_List (Exprs)))),
2508 Make_Attribute_Reference (Loc,
2509 Prefix => New_Occurrence_Of (Xtyp, Loc),
2510 Attribute_Name => Name_Pos,
2511 Expressions => New_List (
2512 Make_Attribute_Reference (Loc,
2514 Duplicate_Subexpr_No_Checks (Pref),
2515 Attribute_Name => Name_First,
2517 New_Copy_List (Exprs)))))))));
2519 Analyze_And_Resolve (N, Typ);
2523 -- Otherwise leave it to gigi
2526 Apply_Universal_Integer_Attribute_Checks (N);
2534 -- Transforms 'Machine into a call to the floating-point attribute
2535 -- function Machine in Fat_xxx (where xxx is the root type)
2537 when Attribute_Machine =>
2538 Expand_Fpt_Attribute_R (N);
2540 ----------------------
2541 -- Machine_Rounding --
2542 ----------------------
2544 -- Transforms 'Machine_Rounding into a call to the floating-point
2545 -- attribute function Machine_Rounding in Fat_xxx (where xxx is the root
2546 -- type). Expansion is avoided for cases the back end can handle
2549 when Attribute_Machine_Rounding =>
2550 if not Is_Inline_Floating_Point_Attribute (N) then
2551 Expand_Fpt_Attribute_R (N);
2558 -- Machine_Size is equivalent to Object_Size, so transform it into
2559 -- Object_Size and that way Gigi never sees Machine_Size.
2561 when Attribute_Machine_Size =>
2563 Make_Attribute_Reference (Loc,
2564 Prefix => Prefix (N),
2565 Attribute_Name => Name_Object_Size));
2567 Analyze_And_Resolve (N, Typ);
2573 -- The only case that can get this far is the dynamic case of the old
2574 -- Ada 83 Mantissa attribute for the fixed-point case. For this case, we
2581 -- ityp (System.Mantissa.Mantissa_Value
2582 -- (Integer'Integer_Value (typ'First),
2583 -- Integer'Integer_Value (typ'Last)));
2585 when Attribute_Mantissa => Mantissa : declare
2586 Ptyp : constant Entity_Id := Etype (Pref);
2591 Make_Function_Call (Loc,
2592 Name => New_Occurrence_Of (RTE (RE_Mantissa_Value), Loc),
2594 Parameter_Associations => New_List (
2596 Make_Attribute_Reference (Loc,
2597 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2598 Attribute_Name => Name_Integer_Value,
2599 Expressions => New_List (
2601 Make_Attribute_Reference (Loc,
2602 Prefix => New_Occurrence_Of (Ptyp, Loc),
2603 Attribute_Name => Name_First))),
2605 Make_Attribute_Reference (Loc,
2606 Prefix => New_Occurrence_Of (Standard_Integer, Loc),
2607 Attribute_Name => Name_Integer_Value,
2608 Expressions => New_List (
2610 Make_Attribute_Reference (Loc,
2611 Prefix => New_Occurrence_Of (Ptyp, Loc),
2612 Attribute_Name => Name_Last)))))));
2614 Analyze_And_Resolve (N, Typ);
2617 --------------------
2618 -- Mechanism_Code --
2619 --------------------
2621 when Attribute_Mechanism_Code =>
2623 -- We must replace the prefix in the renamed case
2625 if Is_Entity_Name (Pref)
2626 and then Present (Alias (Entity (Pref)))
2628 Set_Renamed_Subprogram (Pref, Alias (Entity (Pref)));
2635 when Attribute_Mod => Mod_Case : declare
2636 Arg : constant Node_Id := Relocate_Node (First (Exprs));
2637 Hi : constant Node_Id := Type_High_Bound (Etype (Arg));
2638 Modv : constant Uint := Modulus (Btyp);
2642 -- This is not so simple. The issue is what type to use for the
2643 -- computation of the modular value.
2645 -- The easy case is when the modulus value is within the bounds
2646 -- of the signed integer type of the argument. In this case we can
2647 -- just do the computation in that signed integer type, and then
2648 -- do an ordinary conversion to the target type.
2650 if Modv <= Expr_Value (Hi) then
2655 Right_Opnd => Make_Integer_Literal (Loc, Modv))));
2657 -- Here we know that the modulus is larger than type'Last of the
2658 -- integer type. There are two cases to consider:
2660 -- a) The integer value is non-negative. In this case, it is
2661 -- returned as the result (since it is less than the modulus).
2663 -- b) The integer value is negative. In this case, we know that the
2664 -- result is modulus + value, where the value might be as small as
2665 -- -modulus. The trouble is what type do we use to do the subtract.
2666 -- No type will do, since modulus can be as big as 2**64, and no
2667 -- integer type accomodates this value. Let's do bit of algebra
2670 -- = modulus - (-value)
2671 -- = (modulus - 1) - (-value - 1)
2673 -- Now modulus - 1 is certainly in range of the modular type.
2674 -- -value is in the range 1 .. modulus, so -value -1 is in the
2675 -- range 0 .. modulus-1 which is in range of the modular type.
2676 -- Furthermore, (-value - 1) can be expressed as -(value + 1)
2677 -- which we can compute using the integer base type.
2679 -- Once this is done we analyze the conditional expression without
2680 -- range checks, because we know everything is in range, and we
2681 -- want to prevent spurious warnings on either branch.
2685 Make_Conditional_Expression (Loc,
2686 Expressions => New_List (
2688 Left_Opnd => Duplicate_Subexpr (Arg),
2689 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2692 Duplicate_Subexpr_No_Checks (Arg)),
2694 Make_Op_Subtract (Loc,
2696 Make_Integer_Literal (Loc,
2697 Intval => Modv - 1),
2703 Left_Opnd => Duplicate_Subexpr_No_Checks (Arg),
2705 Make_Integer_Literal (Loc,
2706 Intval => 1))))))));
2710 Analyze_And_Resolve (N, Btyp, Suppress => All_Checks);
2717 -- Transforms 'Model into a call to the floating-point attribute
2718 -- function Model in Fat_xxx (where xxx is the root type)
2720 when Attribute_Model =>
2721 Expand_Fpt_Attribute_R (N);
2727 -- The processing for Object_Size shares the processing for Size
2733 when Attribute_Output => Output : declare
2734 P_Type : constant Entity_Id := Entity (Pref);
2735 U_Type : constant Entity_Id := Underlying_Type (P_Type);
2743 -- If no underlying type, we have an error that will be diagnosed
2744 -- elsewhere, so here we just completely ignore the expansion.
2750 -- If TSS for Output is present, just call it
2752 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Output);
2754 if Present (Pname) then
2758 -- If there is a Stream_Convert pragma, use it, we rewrite
2760 -- sourcetyp'Output (stream, Item)
2764 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
2766 -- where strmwrite is the given Write function that converts an
2767 -- argument of type sourcetyp or a type acctyp, from which it is
2768 -- derived to type strmtyp. The conversion to acttyp is required
2769 -- for the derived case.
2771 Prag := Get_Stream_Convert_Pragma (P_Type);
2773 if Present (Prag) then
2775 Next (Next (First (Pragma_Argument_Associations (Prag))));
2776 Wfunc := Entity (Expression (Arg3));
2779 Make_Attribute_Reference (Loc,
2780 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
2781 Attribute_Name => Name_Output,
2782 Expressions => New_List (
2783 Relocate_Node (First (Exprs)),
2784 Make_Function_Call (Loc,
2785 Name => New_Occurrence_Of (Wfunc, Loc),
2786 Parameter_Associations => New_List (
2787 OK_Convert_To (Etype (First_Formal (Wfunc)),
2788 Relocate_Node (Next (First (Exprs)))))))));
2793 -- For elementary types, we call the W_xxx routine directly.
2794 -- Note that the effect of Write and Output is identical for
2795 -- the case of an elementary type, since there are no
2796 -- discriminants or bounds.
2798 elsif Is_Elementary_Type (U_Type) then
2800 -- A special case arises if we have a defined _Write routine,
2801 -- since in this case we are required to call this routine.
2803 if Present (TSS (Base_Type (U_Type), TSS_Stream_Write)) then
2804 Build_Record_Or_Elementary_Output_Procedure
2805 (Loc, U_Type, Decl, Pname);
2806 Insert_Action (N, Decl);
2808 -- For normal cases, we call the W_xxx routine directly
2811 Rewrite (N, Build_Elementary_Write_Call (N));
2818 elsif Is_Array_Type (U_Type) then
2819 Build_Array_Output_Procedure (Loc, U_Type, Decl, Pname);
2820 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
2822 -- Class-wide case, first output external tag, then dispatch
2823 -- to the appropriate primitive Output function (RM 13.13.2(31)).
2825 elsif Is_Class_Wide_Type (P_Type) then
2827 -- No need to do anything else compiling under restriction
2828 -- No_Dispatching_Calls. During the semantic analysis we
2829 -- already notified such violation.
2831 if Restriction_Active (No_Dispatching_Calls) then
2836 Strm : constant Node_Id := First (Exprs);
2837 Item : constant Node_Id := Next (Strm);
2840 -- Ada 2005 (AI-344): Check that the accessibility level
2841 -- of the type of the output object is not deeper than
2842 -- that of the attribute's prefix type.
2844 -- if Get_Access_Level (Item'Tag)
2845 -- /= Get_Access_Level (P_Type'Tag)
2850 -- String'Output (Strm, External_Tag (Item'Tag));
2852 -- We cannot figure out a practical way to implement this
2853 -- accessibility check on virtual machines, so we omit it.
2855 if Ada_Version >= Ada_05
2856 and then VM_Target = No_VM
2859 Make_Implicit_If_Statement (N,
2863 Build_Get_Access_Level (Loc,
2864 Make_Attribute_Reference (Loc,
2867 Duplicate_Subexpr (Item,
2869 Attribute_Name => Name_Tag)),
2872 Make_Integer_Literal (Loc,
2873 Type_Access_Level (P_Type))),
2876 New_List (Make_Raise_Statement (Loc,
2878 RTE (RE_Tag_Error), Loc)))));
2882 Make_Attribute_Reference (Loc,
2883 Prefix => New_Occurrence_Of (Standard_String, Loc),
2884 Attribute_Name => Name_Output,
2885 Expressions => New_List (
2886 Relocate_Node (Duplicate_Subexpr (Strm)),
2887 Make_Function_Call (Loc,
2889 New_Occurrence_Of (RTE (RE_External_Tag), Loc),
2890 Parameter_Associations => New_List (
2891 Make_Attribute_Reference (Loc,
2894 (Duplicate_Subexpr (Item, Name_Req => True)),
2895 Attribute_Name => Name_Tag))))));
2898 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
2900 -- Tagged type case, use the primitive Output function
2902 elsif Is_Tagged_Type (U_Type) then
2903 Pname := Find_Prim_Op (U_Type, TSS_Stream_Output);
2905 -- All other record type cases, including protected records.
2906 -- The latter only arise for expander generated code for
2907 -- handling shared passive partition access.
2911 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
2913 -- Ada 2005 (AI-216): Program_Error is raised when executing
2914 -- the default implementation of the Output attribute of an
2915 -- unchecked union type if the type lacks default discriminant
2918 if Is_Unchecked_Union (Base_Type (U_Type))
2919 and then No (Discriminant_Constraint (U_Type))
2922 Make_Raise_Program_Error (Loc,
2923 Reason => PE_Unchecked_Union_Restriction));
2928 Build_Record_Or_Elementary_Output_Procedure
2929 (Loc, Base_Type (U_Type), Decl, Pname);
2930 Insert_Action (N, Decl);
2934 -- If we fall through, Pname is the name of the procedure to call
2936 Rewrite_Stream_Proc_Call (Pname);
2943 -- For enumeration types with a standard representation, Pos is
2946 -- For enumeration types, with a non-standard representation we
2947 -- generate a call to the _Rep_To_Pos function created when the
2948 -- type was frozen. The call has the form
2950 -- _rep_to_pos (expr, flag)
2952 -- The parameter flag is True if range checks are enabled, causing
2953 -- Program_Error to be raised if the expression has an invalid
2954 -- representation, and False if range checks are suppressed.
2956 -- For integer types, Pos is equivalent to a simple integer
2957 -- conversion and we rewrite it as such
2959 when Attribute_Pos => Pos :
2961 Etyp : Entity_Id := Base_Type (Entity (Pref));
2964 -- Deal with zero/non-zero boolean values
2966 if Is_Boolean_Type (Etyp) then
2967 Adjust_Condition (First (Exprs));
2968 Etyp := Standard_Boolean;
2969 Set_Prefix (N, New_Occurrence_Of (Standard_Boolean, Loc));
2972 -- Case of enumeration type
2974 if Is_Enumeration_Type (Etyp) then
2976 -- Non-standard enumeration type (generate call)
2978 if Present (Enum_Pos_To_Rep (Etyp)) then
2979 Append_To (Exprs, Rep_To_Pos_Flag (Etyp, Loc));
2982 Make_Function_Call (Loc,
2984 New_Reference_To (TSS (Etyp, TSS_Rep_To_Pos), Loc),
2985 Parameter_Associations => Exprs)));
2987 Analyze_And_Resolve (N, Typ);
2989 -- Standard enumeration type (do universal integer check)
2992 Apply_Universal_Integer_Attribute_Checks (N);
2995 -- Deal with integer types (replace by conversion)
2997 elsif Is_Integer_Type (Etyp) then
2998 Rewrite (N, Convert_To (Typ, First (Exprs)));
2999 Analyze_And_Resolve (N, Typ);
3008 -- We compute this if a component clause was present, otherwise
3009 -- we leave the computation up to Gigi, since we don't know what
3010 -- layout will be chosen.
3012 when Attribute_Position => Position :
3014 CE : constant Entity_Id := Entity (Selector_Name (Pref));
3017 if Present (Component_Clause (CE)) then
3019 Make_Integer_Literal (Loc,
3020 Intval => Component_Bit_Offset (CE) / System_Storage_Unit));
3021 Analyze_And_Resolve (N, Typ);
3024 Apply_Universal_Integer_Attribute_Checks (N);
3032 -- 1. Deal with enumeration types with holes
3033 -- 2. For floating-point, generate call to attribute function
3034 -- 3. For other cases, deal with constraint checking
3036 when Attribute_Pred => Pred :
3038 Ptyp : constant Entity_Id := Base_Type (Etype (Pref));
3041 -- For enumeration types with non-standard representations, we
3042 -- expand typ'Pred (x) into
3044 -- Pos_To_Rep (Rep_To_Pos (x) - 1)
3046 -- If the representation is contiguous, we compute instead
3047 -- Lit1 + Rep_to_Pos (x -1), to catch invalid representations.
3049 if Is_Enumeration_Type (Ptyp)
3050 and then Present (Enum_Pos_To_Rep (Ptyp))
3052 if Has_Contiguous_Rep (Ptyp) then
3054 Unchecked_Convert_To (Ptyp,
3057 Make_Integer_Literal (Loc,
3058 Enumeration_Rep (First_Literal (Ptyp))),
3060 Make_Function_Call (Loc,
3063 (TSS (Ptyp, TSS_Rep_To_Pos), Loc),
3065 Parameter_Associations =>
3067 Unchecked_Convert_To (Ptyp,
3068 Make_Op_Subtract (Loc,
3070 Unchecked_Convert_To (Standard_Integer,
3071 Relocate_Node (First (Exprs))),
3073 Make_Integer_Literal (Loc, 1))),
3074 Rep_To_Pos_Flag (Ptyp, Loc))))));
3077 -- Add Boolean parameter True, to request program errror if
3078 -- we have a bad representation on our hands. If checks are
3079 -- suppressed, then add False instead
3081 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
3083 Make_Indexed_Component (Loc,
3084 Prefix => New_Reference_To (Enum_Pos_To_Rep (Ptyp), Loc),
3085 Expressions => New_List (
3086 Make_Op_Subtract (Loc,
3088 Make_Function_Call (Loc,
3090 New_Reference_To (TSS (Ptyp, TSS_Rep_To_Pos), Loc),
3091 Parameter_Associations => Exprs),
3092 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
3095 Analyze_And_Resolve (N, Typ);
3097 -- For floating-point, we transform 'Pred into a call to the Pred
3098 -- floating-point attribute function in Fat_xxx (xxx is root type)
3100 elsif Is_Floating_Point_Type (Ptyp) then
3101 Expand_Fpt_Attribute_R (N);
3102 Analyze_And_Resolve (N, Typ);
3104 -- For modular types, nothing to do (no overflow, since wraps)
3106 elsif Is_Modular_Integer_Type (Ptyp) then
3109 -- For other types, if range checking is enabled, we must generate
3110 -- a check if overflow checking is enabled.
3112 elsif not Overflow_Checks_Suppressed (Ptyp) then
3113 Expand_Pred_Succ (N);
3121 -- Ada 2005 (AI-327): Dynamic ceiling priorities
3123 -- We rewrite X'Priority as the following run-time call:
3125 -- Get_Ceiling (X._Object)
3127 -- Note that although X'Priority is notionally an object, it is quite
3128 -- deliberately not defined as an aliased object in the RM. This means
3129 -- that it works fine to rewrite it as a call, without having to worry
3130 -- about complications that would other arise from X'Priority'Access,
3131 -- which is illegal, because of the lack of aliasing.
3133 when Attribute_Priority =>
3136 Conctyp : Entity_Id;
3137 Object_Parm : Node_Id;
3139 RT_Subprg_Name : Node_Id;
3142 -- Look for the enclosing concurrent type
3144 Conctyp := Current_Scope;
3145 while not Is_Concurrent_Type (Conctyp) loop
3146 Conctyp := Scope (Conctyp);
3149 pragma Assert (Is_Protected_Type (Conctyp));
3151 -- Generate the actual of the call
3153 Subprg := Current_Scope;
3154 while not Present (Protected_Body_Subprogram (Subprg)) loop
3155 Subprg := Scope (Subprg);
3158 -- Use of 'Priority inside protected entries and barriers (in
3159 -- both cases the type of the first formal of their expanded
3160 -- subprogram is Address)
3162 if Etype (First_Entity (Protected_Body_Subprogram (Subprg)))
3166 New_Itype : Entity_Id;
3169 -- In the expansion of protected entries the type of the
3170 -- first formal of the Protected_Body_Subprogram is an
3171 -- Address. In order to reference the _object component
3174 -- type T is access p__ptTV;
3177 New_Itype := Create_Itype (E_Access_Type, N);
3178 Set_Etype (New_Itype, New_Itype);
3179 Init_Esize (New_Itype);
3180 Init_Size_Align (New_Itype);
3181 Set_Directly_Designated_Type (New_Itype,
3182 Corresponding_Record_Type (Conctyp));
3183 Freeze_Itype (New_Itype, N);
3186 -- T!(O)._object'unchecked_access
3189 Make_Attribute_Reference (Loc,
3191 Make_Selected_Component (Loc,
3193 Unchecked_Convert_To (New_Itype,
3196 (Protected_Body_Subprogram (Subprg)),
3199 Make_Identifier (Loc, Name_uObject)),
3200 Attribute_Name => Name_Unchecked_Access);
3203 -- Use of 'Priority inside a protected subprogram
3207 Make_Attribute_Reference (Loc,
3209 Make_Selected_Component (Loc,
3210 Prefix => New_Reference_To
3212 (Protected_Body_Subprogram (Subprg)),
3215 Make_Identifier (Loc, Name_uObject)),
3216 Attribute_Name => Name_Unchecked_Access);
3219 -- Select the appropriate run-time subprogram
3221 if Number_Entries (Conctyp) = 0 then
3223 New_Reference_To (RTE (RE_Get_Ceiling), Loc);
3226 New_Reference_To (RTE (RO_PE_Get_Ceiling), Loc);
3230 Make_Function_Call (Loc,
3231 Name => RT_Subprg_Name,
3232 Parameter_Associations => New_List (Object_Parm));
3236 -- Avoid the generation of extra checks on the pointer to the
3237 -- protected object.
3239 Analyze_And_Resolve (N, Typ, Suppress => Access_Check);
3246 when Attribute_Range_Length => Range_Length : declare
3247 P_Type : constant Entity_Id := Etype (Pref);
3250 -- The only special processing required is for the case where
3251 -- Range_Length is applied to an enumeration type with holes.
3252 -- In this case we transform
3258 -- X'Pos (X'Last) - X'Pos (X'First) + 1
3260 -- So that the result reflects the proper Pos values instead
3261 -- of the underlying representations.
3263 if Is_Enumeration_Type (P_Type)
3264 and then Has_Non_Standard_Rep (P_Type)
3269 Make_Op_Subtract (Loc,
3271 Make_Attribute_Reference (Loc,
3272 Attribute_Name => Name_Pos,
3273 Prefix => New_Occurrence_Of (P_Type, Loc),
3274 Expressions => New_List (
3275 Make_Attribute_Reference (Loc,
3276 Attribute_Name => Name_Last,
3277 Prefix => New_Occurrence_Of (P_Type, Loc)))),
3280 Make_Attribute_Reference (Loc,
3281 Attribute_Name => Name_Pos,
3282 Prefix => New_Occurrence_Of (P_Type, Loc),
3283 Expressions => New_List (
3284 Make_Attribute_Reference (Loc,
3285 Attribute_Name => Name_First,
3286 Prefix => New_Occurrence_Of (P_Type, Loc))))),
3289 Make_Integer_Literal (Loc, 1)));
3291 Analyze_And_Resolve (N, Typ);
3293 -- For all other cases, attribute is handled by Gigi, but we need
3294 -- to deal with the case of the range check on a universal integer.
3297 Apply_Universal_Integer_Attribute_Checks (N);
3305 when Attribute_Read => Read : declare
3306 P_Type : constant Entity_Id := Entity (Pref);
3307 B_Type : constant Entity_Id := Base_Type (P_Type);
3308 U_Type : constant Entity_Id := Underlying_Type (P_Type);
3318 -- If no underlying type, we have an error that will be diagnosed
3319 -- elsewhere, so here we just completely ignore the expansion.
3325 -- The simple case, if there is a TSS for Read, just call it
3327 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Read);
3329 if Present (Pname) then
3333 -- If there is a Stream_Convert pragma, use it, we rewrite
3335 -- sourcetyp'Read (stream, Item)
3339 -- Item := sourcetyp (strmread (strmtyp'Input (Stream)));
3341 -- where strmread is the given Read function that converts an
3342 -- argument of type strmtyp to type sourcetyp or a type from which
3343 -- it is derived. The conversion to sourcetyp is required in the
3346 -- A special case arises if Item is a type conversion in which
3347 -- case, we have to expand to:
3349 -- Itemx := typex (strmread (strmtyp'Input (Stream)));
3351 -- where Itemx is the expression of the type conversion (i.e.
3352 -- the actual object), and typex is the type of Itemx.
3354 Prag := Get_Stream_Convert_Pragma (P_Type);
3356 if Present (Prag) then
3357 Arg2 := Next (First (Pragma_Argument_Associations (Prag)));
3358 Rfunc := Entity (Expression (Arg2));
3359 Lhs := Relocate_Node (Next (First (Exprs)));
3361 OK_Convert_To (B_Type,
3362 Make_Function_Call (Loc,
3363 Name => New_Occurrence_Of (Rfunc, Loc),
3364 Parameter_Associations => New_List (
3365 Make_Attribute_Reference (Loc,
3368 (Etype (First_Formal (Rfunc)), Loc),
3369 Attribute_Name => Name_Input,
3370 Expressions => New_List (
3371 Relocate_Node (First (Exprs)))))));
3373 if Nkind (Lhs) = N_Type_Conversion then
3374 Lhs := Expression (Lhs);
3375 Rhs := Convert_To (Etype (Lhs), Rhs);
3379 Make_Assignment_Statement (Loc,
3381 Expression => Rhs));
3382 Set_Assignment_OK (Lhs);
3386 -- For elementary types, we call the I_xxx routine using the first
3387 -- parameter and then assign the result into the second parameter.
3388 -- We set Assignment_OK to deal with the conversion case.
3390 elsif Is_Elementary_Type (U_Type) then
3396 Lhs := Relocate_Node (Next (First (Exprs)));
3397 Rhs := Build_Elementary_Input_Call (N);
3399 if Nkind (Lhs) = N_Type_Conversion then
3400 Lhs := Expression (Lhs);
3401 Rhs := Convert_To (Etype (Lhs), Rhs);
3404 Set_Assignment_OK (Lhs);
3407 Make_Assignment_Statement (Loc,
3409 Expression => Rhs));
3417 elsif Is_Array_Type (U_Type) then
3418 Build_Array_Read_Procedure (N, U_Type, Decl, Pname);
3419 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
3421 -- Tagged type case, use the primitive Read function. Note that
3422 -- this will dispatch in the class-wide case which is what we want
3424 elsif Is_Tagged_Type (U_Type) then
3425 Pname := Find_Prim_Op (U_Type, TSS_Stream_Read);
3427 -- All other record type cases, including protected records. The
3428 -- latter only arise for expander generated code for handling
3429 -- shared passive partition access.
3433 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
3435 -- Ada 2005 (AI-216): Program_Error is raised when executing
3436 -- the default implementation of the Read attribute of an
3437 -- Unchecked_Union type.
3439 if Is_Unchecked_Union (Base_Type (U_Type)) then
3441 Make_Raise_Program_Error (Loc,
3442 Reason => PE_Unchecked_Union_Restriction));
3445 if Has_Discriminants (U_Type)
3447 (Discriminant_Default_Value (First_Discriminant (U_Type)))
3449 Build_Mutable_Record_Read_Procedure
3450 (Loc, Base_Type (U_Type), Decl, Pname);
3452 Build_Record_Read_Procedure
3453 (Loc, Base_Type (U_Type), Decl, Pname);
3456 -- Suppress checks, uninitialized or otherwise invalid
3457 -- data does not cause constraint errors to be raised for
3458 -- a complete record read.
3460 Insert_Action (N, Decl, All_Checks);
3464 Rewrite_Stream_Proc_Call (Pname);
3471 -- Transforms 'Remainder into a call to the floating-point attribute
3472 -- function Remainder in Fat_xxx (where xxx is the root type)
3474 when Attribute_Remainder =>
3475 Expand_Fpt_Attribute_RR (N);
3481 -- The handling of the Round attribute is quite delicate. The processing
3482 -- in Sem_Attr introduced a conversion to universal real, reflecting the
3483 -- semantics of Round, but we do not want anything to do with universal
3484 -- real at runtime, since this corresponds to using floating-point
3487 -- What we have now is that the Etype of the Round attribute correctly
3488 -- indicates the final result type. The operand of the Round is the
3489 -- conversion to universal real, described above, and the operand of
3490 -- this conversion is the actual operand of Round, which may be the
3491 -- special case of a fixed point multiplication or division (Etype =
3494 -- The exapander will expand first the operand of the conversion, then
3495 -- the conversion, and finally the round attribute itself, since we
3496 -- always work inside out. But we cannot simply process naively in this
3497 -- order. In the semantic world where universal fixed and real really
3498 -- exist and have infinite precision, there is no problem, but in the
3499 -- implementation world, where universal real is a floating-point type,
3500 -- we would get the wrong result.
3502 -- So the approach is as follows. First, when expanding a multiply or
3503 -- divide whose type is universal fixed, we do nothing at all, instead
3504 -- deferring the operation till later.
3506 -- The actual processing is done in Expand_N_Type_Conversion which
3507 -- handles the special case of Round by looking at its parent to see if
3508 -- it is a Round attribute, and if it is, handling the conversion (or
3509 -- its fixed multiply/divide child) in an appropriate manner.
3511 -- This means that by the time we get to expanding the Round attribute
3512 -- itself, the Round is nothing more than a type conversion (and will
3513 -- often be a null type conversion), so we just replace it with the
3514 -- appropriate conversion operation.
3516 when Attribute_Round =>
3518 Convert_To (Etype (N), Relocate_Node (First (Exprs))));
3519 Analyze_And_Resolve (N);
3525 -- Transforms 'Rounding into a call to the floating-point attribute
3526 -- function Rounding in Fat_xxx (where xxx is the root type)
3528 when Attribute_Rounding =>
3529 Expand_Fpt_Attribute_R (N);
3535 -- Transforms 'Scaling into a call to the floating-point attribute
3536 -- function Scaling in Fat_xxx (where xxx is the root type)
3538 when Attribute_Scaling =>
3539 Expand_Fpt_Attribute_RI (N);
3545 when Attribute_Size |
3546 Attribute_Object_Size |
3547 Attribute_Value_Size |
3548 Attribute_VADS_Size => Size :
3551 Ptyp : constant Entity_Id := Etype (Pref);
3556 -- Processing for VADS_Size case. Note that this processing removes
3557 -- all traces of VADS_Size from the tree, and completes all required
3558 -- processing for VADS_Size by translating the attribute reference
3559 -- to an appropriate Size or Object_Size reference.
3561 if Id = Attribute_VADS_Size
3562 or else (Use_VADS_Size and then Id = Attribute_Size)
3564 -- If the size is specified, then we simply use the specified
3565 -- size. This applies to both types and objects. The size of an
3566 -- object can be specified in the following ways:
3568 -- An explicit size object is given for an object
3569 -- A component size is specified for an indexed component
3570 -- A component clause is specified for a selected component
3571 -- The object is a component of a packed composite object
3573 -- If the size is specified, then VADS_Size of an object
3575 if (Is_Entity_Name (Pref)
3576 and then Present (Size_Clause (Entity (Pref))))
3578 (Nkind (Pref) = N_Component_Clause
3579 and then (Present (Component_Clause
3580 (Entity (Selector_Name (Pref))))
3581 or else Is_Packed (Etype (Prefix (Pref)))))
3583 (Nkind (Pref) = N_Indexed_Component
3584 and then (Component_Size (Etype (Prefix (Pref))) /= 0
3585 or else Is_Packed (Etype (Prefix (Pref)))))
3587 Set_Attribute_Name (N, Name_Size);
3589 -- Otherwise if we have an object rather than a type, then the
3590 -- VADS_Size attribute applies to the type of the object, rather
3591 -- than the object itself. This is one of the respects in which
3592 -- VADS_Size differs from Size.
3595 if (not Is_Entity_Name (Pref)
3596 or else not Is_Type (Entity (Pref)))
3597 and then (Is_Scalar_Type (Etype (Pref))
3598 or else Is_Constrained (Etype (Pref)))
3600 Rewrite (Pref, New_Occurrence_Of (Etype (Pref), Loc));
3603 -- For a scalar type for which no size was explicitly given,
3604 -- VADS_Size means Object_Size. This is the other respect in
3605 -- which VADS_Size differs from Size.
3607 if Is_Scalar_Type (Etype (Pref))
3608 and then No (Size_Clause (Etype (Pref)))
3610 Set_Attribute_Name (N, Name_Object_Size);
3612 -- In all other cases, Size and VADS_Size are the sane
3615 Set_Attribute_Name (N, Name_Size);
3620 -- For class-wide types, X'Class'Size is transformed into a
3621 -- direct reference to the Size of the class type, so that gigi
3622 -- does not have to deal with the X'Class'Size reference.
3624 if Is_Entity_Name (Pref)
3625 and then Is_Class_Wide_Type (Entity (Pref))
3627 Rewrite (Prefix (N), New_Occurrence_Of (Entity (Pref), Loc));
3630 -- For X'Size applied to an object of a class-wide type, transform
3631 -- X'Size into a call to the primitive operation _Size applied to X.
3633 elsif Is_Class_Wide_Type (Ptyp) then
3635 -- No need to do anything else compiling under restriction
3636 -- No_Dispatching_Calls. During the semantic analysis we
3637 -- already notified such violation.
3639 if Restriction_Active (No_Dispatching_Calls) then
3644 Make_Function_Call (Loc,
3645 Name => New_Reference_To
3646 (Find_Prim_Op (Ptyp, Name_uSize), Loc),
3647 Parameter_Associations => New_List (Pref));
3649 if Typ /= Standard_Long_Long_Integer then
3651 -- The context is a specific integer type with which the
3652 -- original attribute was compatible. The function has a
3653 -- specific type as well, so to preserve the compatibility
3654 -- we must convert explicitly.
3656 New_Node := Convert_To (Typ, New_Node);
3659 Rewrite (N, New_Node);
3660 Analyze_And_Resolve (N, Typ);
3663 -- Case of known RM_Size of a type
3665 elsif (Id = Attribute_Size or else Id = Attribute_Value_Size)
3666 and then Is_Entity_Name (Pref)
3667 and then Is_Type (Entity (Pref))
3668 and then Known_Static_RM_Size (Entity (Pref))
3670 Siz := RM_Size (Entity (Pref));
3672 -- Case of known Esize of a type
3674 elsif Id = Attribute_Object_Size
3675 and then Is_Entity_Name (Pref)
3676 and then Is_Type (Entity (Pref))
3677 and then Known_Static_Esize (Entity (Pref))
3679 Siz := Esize (Entity (Pref));
3681 -- Case of known size of object
3683 elsif Id = Attribute_Size
3684 and then Is_Entity_Name (Pref)
3685 and then Is_Object (Entity (Pref))
3686 and then Known_Esize (Entity (Pref))
3687 and then Known_Static_Esize (Entity (Pref))
3689 Siz := Esize (Entity (Pref));
3691 -- For an array component, we can do Size in the front end
3692 -- if the component_size of the array is set.
3694 elsif Nkind (Pref) = N_Indexed_Component then
3695 Siz := Component_Size (Etype (Prefix (Pref)));
3697 -- For a record component, we can do Size in the front end if there
3698 -- is a component clause, or if the record is packed and the
3699 -- component's size is known at compile time.
3701 elsif Nkind (Pref) = N_Selected_Component then
3703 Rec : constant Entity_Id := Etype (Prefix (Pref));
3704 Comp : constant Entity_Id := Entity (Selector_Name (Pref));
3707 if Present (Component_Clause (Comp)) then
3708 Siz := Esize (Comp);
3710 elsif Is_Packed (Rec) then
3711 Siz := RM_Size (Ptyp);
3714 Apply_Universal_Integer_Attribute_Checks (N);
3719 -- All other cases are handled by Gigi
3722 Apply_Universal_Integer_Attribute_Checks (N);
3724 -- If Size is applied to a formal parameter that is of a packed
3725 -- array subtype, then apply Size to the actual subtype.
3727 if Is_Entity_Name (Pref)
3728 and then Is_Formal (Entity (Pref))
3729 and then Is_Array_Type (Etype (Pref))
3730 and then Is_Packed (Etype (Pref))
3733 Make_Attribute_Reference (Loc,
3735 New_Occurrence_Of (Get_Actual_Subtype (Pref), Loc),
3736 Attribute_Name => Name_Size));
3737 Analyze_And_Resolve (N, Typ);
3740 -- If Size applies to a dereference of an access to unconstrained
3741 -- packed array, GIGI needs to see its unconstrained nominal type,
3742 -- but also a hint to the actual constrained type.
3744 if Nkind (Pref) = N_Explicit_Dereference
3745 and then Is_Array_Type (Etype (Pref))
3746 and then not Is_Constrained (Etype (Pref))
3747 and then Is_Packed (Etype (Pref))
3749 Set_Actual_Designated_Subtype (Pref,
3750 Get_Actual_Subtype (Pref));
3756 -- Common processing for record and array component case
3758 if Siz /= No_Uint and then Siz /= 0 then
3760 CS : constant Boolean := Comes_From_Source (N);
3763 Rewrite (N, Make_Integer_Literal (Loc, Siz));
3765 -- This integer literal is not a static expression. We do not
3766 -- call Analyze_And_Resolve here, because this would activate
3767 -- the circuit for deciding that a static value was out of
3768 -- range, and we don't want that.
3770 -- So just manually set the type, mark the expression as non-
3771 -- static, and then ensure that the result is checked properly
3772 -- if the attribute comes from source (if it was internally
3773 -- generated, we never need a constraint check).
3776 Set_Is_Static_Expression (N, False);
3779 Apply_Constraint_Check (N, Typ);
3789 when Attribute_Storage_Pool =>
3791 Make_Type_Conversion (Loc,
3792 Subtype_Mark => New_Reference_To (Etype (N), Loc),
3793 Expression => New_Reference_To (Entity (N), Loc)));
3794 Analyze_And_Resolve (N, Typ);
3800 when Attribute_Storage_Size => Storage_Size :
3802 Ptyp : constant Entity_Id := Etype (Pref);
3805 -- Access type case, always go to the root type
3807 -- The case of access types results in a value of zero for the case
3808 -- where no storage size attribute clause has been given. If a
3809 -- storage size has been given, then the attribute is converted
3810 -- to a reference to the variable used to hold this value.
3812 if Is_Access_Type (Ptyp) then
3813 if Present (Storage_Size_Variable (Root_Type (Ptyp))) then
3815 Make_Attribute_Reference (Loc,
3816 Prefix => New_Reference_To (Typ, Loc),
3817 Attribute_Name => Name_Max,
3818 Expressions => New_List (
3819 Make_Integer_Literal (Loc, 0),
3822 (Storage_Size_Variable (Root_Type (Ptyp)), Loc)))));
3824 elsif Present (Associated_Storage_Pool (Root_Type (Ptyp))) then
3827 Make_Function_Call (Loc,
3831 (Etype (Associated_Storage_Pool (Root_Type (Ptyp))),
3832 Attribute_Name (N)),
3835 Parameter_Associations => New_List (
3837 (Associated_Storage_Pool (Root_Type (Ptyp)), Loc)))));
3840 Rewrite (N, Make_Integer_Literal (Loc, 0));
3843 Analyze_And_Resolve (N, Typ);
3845 -- For tasks, we retrieve the size directly from the TCB. The
3846 -- size may depend on a discriminant of the type, and therefore
3847 -- can be a per-object expression, so type-level information is
3848 -- not sufficient in general. There are four cases to consider:
3850 -- a) If the attribute appears within a task body, the designated
3851 -- TCB is obtained by a call to Self.
3853 -- b) If the prefix of the attribute is the name of a task object,
3854 -- the designated TCB is the one stored in the corresponding record.
3856 -- c) If the prefix is a task type, the size is obtained from the
3857 -- size variable created for each task type
3859 -- d) If no storage_size was specified for the type , there is no
3860 -- size variable, and the value is a system-specific default.
3863 if In_Open_Scopes (Ptyp) then
3865 -- Storage_Size (Self)
3869 Make_Function_Call (Loc,
3871 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
3872 Parameter_Associations =>
3874 Make_Function_Call (Loc,
3876 New_Reference_To (RTE (RE_Self), Loc))))));
3878 elsif not Is_Entity_Name (Pref)
3879 or else not Is_Type (Entity (Pref))
3881 -- Storage_Size (Rec (Obj).Size)
3885 Make_Function_Call (Loc,
3887 New_Occurrence_Of (RTE (RE_Storage_Size), Loc),
3888 Parameter_Associations =>
3890 Make_Selected_Component (Loc,
3892 Unchecked_Convert_To (
3893 Corresponding_Record_Type (Ptyp),
3894 New_Copy_Tree (Pref)),
3896 Make_Identifier (Loc, Name_uTask_Id))))));
3898 elsif Present (Storage_Size_Variable (Ptyp)) then
3900 -- Static storage size pragma given for type: retrieve value
3901 -- from its allocated storage variable.
3905 Make_Function_Call (Loc,
3906 Name => New_Occurrence_Of (
3907 RTE (RE_Adjust_Storage_Size), Loc),
3908 Parameter_Associations =>
3911 Storage_Size_Variable (Ptyp), Loc)))));
3913 -- Get system default
3917 Make_Function_Call (Loc,
3920 RTE (RE_Default_Stack_Size), Loc))));
3923 Analyze_And_Resolve (N, Typ);
3931 when Attribute_Stream_Size => Stream_Size : declare
3932 Ptyp : constant Entity_Id := Etype (Pref);
3936 -- If we have a Stream_Size clause for this type use it, otherwise
3937 -- the Stream_Size if the size of the type.
3939 if Has_Stream_Size_Clause (Ptyp) then
3942 (Static_Integer (Expression (Stream_Size_Clause (Ptyp))));
3944 Size := UI_To_Int (Esize (Ptyp));
3947 Rewrite (N, Make_Integer_Literal (Loc, Intval => Size));
3948 Analyze_And_Resolve (N, Typ);
3955 -- 1. Deal with enumeration types with holes
3956 -- 2. For floating-point, generate call to attribute function
3957 -- 3. For other cases, deal with constraint checking
3959 when Attribute_Succ => Succ :
3961 Ptyp : constant Entity_Id := Base_Type (Etype (Pref));
3964 -- For enumeration types with non-standard representations, we
3965 -- expand typ'Succ (x) into
3967 -- Pos_To_Rep (Rep_To_Pos (x) + 1)
3969 -- If the representation is contiguous, we compute instead
3970 -- Lit1 + Rep_to_Pos (x+1), to catch invalid representations.
3972 if Is_Enumeration_Type (Ptyp)
3973 and then Present (Enum_Pos_To_Rep (Ptyp))
3975 if Has_Contiguous_Rep (Ptyp) then
3977 Unchecked_Convert_To (Ptyp,
3980 Make_Integer_Literal (Loc,
3981 Enumeration_Rep (First_Literal (Ptyp))),
3983 Make_Function_Call (Loc,
3986 (TSS (Ptyp, TSS_Rep_To_Pos), Loc),
3988 Parameter_Associations =>
3990 Unchecked_Convert_To (Ptyp,
3993 Unchecked_Convert_To (Standard_Integer,
3994 Relocate_Node (First (Exprs))),
3996 Make_Integer_Literal (Loc, 1))),
3997 Rep_To_Pos_Flag (Ptyp, Loc))))));
3999 -- Add Boolean parameter True, to request program errror if
4000 -- we have a bad representation on our hands. Add False if
4001 -- checks are suppressed.
4003 Append_To (Exprs, Rep_To_Pos_Flag (Ptyp, Loc));
4005 Make_Indexed_Component (Loc,
4006 Prefix => New_Reference_To (Enum_Pos_To_Rep (Ptyp), Loc),
4007 Expressions => New_List (
4010 Make_Function_Call (Loc,
4013 (TSS (Ptyp, TSS_Rep_To_Pos), Loc),
4014 Parameter_Associations => Exprs),
4015 Right_Opnd => Make_Integer_Literal (Loc, 1)))));
4018 Analyze_And_Resolve (N, Typ);
4020 -- For floating-point, we transform 'Succ into a call to the Succ
4021 -- floating-point attribute function in Fat_xxx (xxx is root type)
4023 elsif Is_Floating_Point_Type (Ptyp) then
4024 Expand_Fpt_Attribute_R (N);
4025 Analyze_And_Resolve (N, Typ);
4027 -- For modular types, nothing to do (no overflow, since wraps)
4029 elsif Is_Modular_Integer_Type (Ptyp) then
4032 -- For other types, if range checking is enabled, we must generate
4033 -- a check if overflow checking is enabled.
4035 elsif not Overflow_Checks_Suppressed (Ptyp) then
4036 Expand_Pred_Succ (N);
4044 -- Transforms X'Tag into a direct reference to the tag of X
4046 when Attribute_Tag => Tag :
4049 Prefix_Is_Type : Boolean;
4052 if Is_Entity_Name (Pref) and then Is_Type (Entity (Pref)) then
4053 Ttyp := Entity (Pref);
4054 Prefix_Is_Type := True;
4056 Ttyp := Etype (Pref);
4057 Prefix_Is_Type := False;
4060 if Is_Class_Wide_Type (Ttyp) then
4061 Ttyp := Root_Type (Ttyp);
4064 Ttyp := Underlying_Type (Ttyp);
4066 if Prefix_Is_Type then
4068 -- For VMs we leave the type attribute unexpanded because
4069 -- there's not a dispatching table to reference.
4071 if VM_Target = No_VM then
4073 Unchecked_Convert_To (RTE (RE_Tag),
4075 (Node (First_Elmt (Access_Disp_Table (Ttyp))), Loc)));
4076 Analyze_And_Resolve (N, RTE (RE_Tag));
4079 -- (Ada 2005 (AI-251): The use of 'Tag in the sources always
4080 -- references the primary tag of the actual object. If 'Tag is
4081 -- applied to class-wide interface objects we generate code that
4082 -- displaces "this" to reference the base of the object.
4084 elsif Comes_From_Source (N)
4085 and then Is_Class_Wide_Type (Etype (Prefix (N)))
4086 and then Is_Interface (Etype (Prefix (N)))
4089 -- (To_Tag_Ptr (Prefix'Address)).all
4091 -- Note that Prefix'Address is recursively expanded into a call
4092 -- to Base_Address (Obj.Tag)
4094 -- Not needed for VM targets, since all handled by the VM
4096 if VM_Target = No_VM then
4098 Make_Explicit_Dereference (Loc,
4099 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
4100 Make_Attribute_Reference (Loc,
4101 Prefix => Relocate_Node (Pref),
4102 Attribute_Name => Name_Address))));
4103 Analyze_And_Resolve (N, RTE (RE_Tag));
4108 Make_Selected_Component (Loc,
4109 Prefix => Relocate_Node (Pref),
4111 New_Reference_To (First_Tag_Component (Ttyp), Loc)));
4112 Analyze_And_Resolve (N, RTE (RE_Tag));
4120 -- Transforms 'Terminated attribute into a call to Terminated function
4122 when Attribute_Terminated => Terminated :
4124 -- The prefix of Terminated is of a task interface class-wide type.
4127 -- terminated (Task_Id (Pref._disp_get_task_id));
4129 if Ada_Version >= Ada_05
4130 and then Ekind (Etype (Pref)) = E_Class_Wide_Type
4131 and then Is_Interface (Etype (Pref))
4132 and then Is_Task_Interface (Etype (Pref))
4135 Make_Function_Call (Loc,
4137 New_Reference_To (RTE (RE_Terminated), Loc),
4138 Parameter_Associations => New_List (
4139 Make_Unchecked_Type_Conversion (Loc,
4141 New_Reference_To (RTE (RO_ST_Task_Id), Loc),
4143 Make_Selected_Component (Loc,
4145 New_Copy_Tree (Pref),
4147 Make_Identifier (Loc, Name_uDisp_Get_Task_Id))))));
4149 elsif Restricted_Profile then
4151 Build_Call_With_Task (Pref, RTE (RE_Restricted_Terminated)));
4155 Build_Call_With_Task (Pref, RTE (RE_Terminated)));
4158 Analyze_And_Resolve (N, Standard_Boolean);
4165 -- Transforms System'To_Address (X) into unchecked conversion
4166 -- from (integral) type of X to type address.
4168 when Attribute_To_Address =>
4170 Unchecked_Convert_To (RTE (RE_Address),
4171 Relocate_Node (First (Exprs))));
4172 Analyze_And_Resolve (N, RTE (RE_Address));
4178 -- Transforms 'Truncation into a call to the floating-point attribute
4179 -- function Truncation in Fat_xxx (where xxx is the root type).
4180 -- Expansion is avoided for cases the back end can handle directly.
4182 when Attribute_Truncation =>
4183 if not Is_Inline_Floating_Point_Attribute (N) then
4184 Expand_Fpt_Attribute_R (N);
4187 -----------------------
4188 -- Unbiased_Rounding --
4189 -----------------------
4191 -- Transforms 'Unbiased_Rounding into a call to the floating-point
4192 -- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the
4193 -- root type). Expansion is avoided for cases the back end can handle
4196 when Attribute_Unbiased_Rounding =>
4197 if not Is_Inline_Floating_Point_Attribute (N) then
4198 Expand_Fpt_Attribute_R (N);
4205 when Attribute_UET_Address => UET_Address : declare
4206 Ent : constant Entity_Id :=
4207 Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
4211 Make_Object_Declaration (Loc,
4212 Defining_Identifier => Ent,
4213 Aliased_Present => True,
4214 Object_Definition =>
4215 New_Occurrence_Of (RTE (RE_Address), Loc)));
4217 -- Construct name __gnat_xxx__SDP, where xxx is the unit name
4218 -- in normal external form.
4220 Get_External_Unit_Name_String (Get_Unit_Name (Pref));
4221 Name_Buffer (1 + 7 .. Name_Len + 7) := Name_Buffer (1 .. Name_Len);
4222 Name_Len := Name_Len + 7;
4223 Name_Buffer (1 .. 7) := "__gnat_";
4224 Name_Buffer (Name_Len + 1 .. Name_Len + 5) := "__SDP";
4225 Name_Len := Name_Len + 5;
4227 Set_Is_Imported (Ent);
4228 Set_Interface_Name (Ent,
4229 Make_String_Literal (Loc,
4230 Strval => String_From_Name_Buffer));
4232 -- Set entity as internal to ensure proper Sprint output of its
4233 -- implicit importation.
4235 Set_Is_Internal (Ent);
4238 Make_Attribute_Reference (Loc,
4239 Prefix => New_Occurrence_Of (Ent, Loc),
4240 Attribute_Name => Name_Address));
4242 Analyze_And_Resolve (N, Typ);
4249 -- The processing for VADS_Size is shared with Size
4255 -- For enumeration types with a standard representation, and for all
4256 -- other types, Val is handled by Gigi. For enumeration types with
4257 -- a non-standard representation we use the _Pos_To_Rep array that
4258 -- was created when the type was frozen.
4260 when Attribute_Val => Val :
4262 Etyp : constant Entity_Id := Base_Type (Entity (Pref));
4265 if Is_Enumeration_Type (Etyp)
4266 and then Present (Enum_Pos_To_Rep (Etyp))
4268 if Has_Contiguous_Rep (Etyp) then
4270 Rep_Node : constant Node_Id :=
4271 Unchecked_Convert_To (Etyp,
4274 Make_Integer_Literal (Loc,
4275 Enumeration_Rep (First_Literal (Etyp))),
4277 (Convert_To (Standard_Integer,
4278 Relocate_Node (First (Exprs))))));
4282 Unchecked_Convert_To (Etyp,
4285 Make_Integer_Literal (Loc,
4286 Enumeration_Rep (First_Literal (Etyp))),
4288 Make_Function_Call (Loc,
4291 (TSS (Etyp, TSS_Rep_To_Pos), Loc),
4292 Parameter_Associations => New_List (
4294 Rep_To_Pos_Flag (Etyp, Loc))))));
4299 Make_Indexed_Component (Loc,
4300 Prefix => New_Reference_To (Enum_Pos_To_Rep (Etyp), Loc),
4301 Expressions => New_List (
4302 Convert_To (Standard_Integer,
4303 Relocate_Node (First (Exprs))))));
4306 Analyze_And_Resolve (N, Typ);
4314 -- The code for valid is dependent on the particular types involved.
4315 -- See separate sections below for the generated code in each case.
4317 when Attribute_Valid => Valid :
4319 Ptyp : constant Entity_Id := Etype (Pref);
4320 Btyp : Entity_Id := Base_Type (Ptyp);
4323 Save_Validity_Checks_On : constant Boolean := Validity_Checks_On;
4324 -- Save the validity checking mode. We always turn off validity
4325 -- checking during process of 'Valid since this is one place
4326 -- where we do not want the implicit validity checks to intefere
4327 -- with the explicit validity check that the programmer is doing.
4329 function Make_Range_Test return Node_Id;
4330 -- Build the code for a range test of the form
4331 -- Btyp!(Pref) >= Btyp!(Ptyp'First)
4333 -- Btyp!(Pref) <= Btyp!(Ptyp'Last)
4335 ---------------------
4336 -- Make_Range_Test --
4337 ---------------------
4339 function Make_Range_Test return Node_Id is
4346 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
4349 Unchecked_Convert_To (Btyp,
4350 Make_Attribute_Reference (Loc,
4351 Prefix => New_Occurrence_Of (Ptyp, Loc),
4352 Attribute_Name => Name_First))),
4357 Unchecked_Convert_To (Btyp,
4358 Duplicate_Subexpr_No_Checks (Pref)),
4361 Unchecked_Convert_To (Btyp,
4362 Make_Attribute_Reference (Loc,
4363 Prefix => New_Occurrence_Of (Ptyp, Loc),
4364 Attribute_Name => Name_Last))));
4365 end Make_Range_Test;
4367 -- Start of processing for Attribute_Valid
4370 -- Turn off validity checks. We do not want any implicit validity
4371 -- checks to intefere with the explicit check from the attribute
4373 Validity_Checks_On := False;
4375 -- Floating-point case. This case is handled by the Valid attribute
4376 -- code in the floating-point attribute run-time library.
4378 if Is_Floating_Point_Type (Ptyp) then
4384 -- For vax fpt types, call appropriate routine in special vax
4385 -- floating point unit. We do not have to worry about loads in
4386 -- this case, since these types have no signalling NaN's.
4388 if Vax_Float (Btyp) then
4389 Expand_Vax_Valid (N);
4391 -- The AAMP back end handles Valid for floating-point types
4393 elsif Is_AAMP_Float (Btyp) then
4394 Analyze_And_Resolve (Pref, Ptyp);
4395 Set_Etype (N, Standard_Boolean);
4398 -- Non VAX float case
4401 Find_Fat_Info (Etype (Pref), Ftp, Pkg);
4403 -- If the floating-point object might be unaligned, we need
4404 -- to call the special routine Unaligned_Valid, which makes
4405 -- the needed copy, being careful not to load the value into
4406 -- any floating-point register. The argument in this case is
4407 -- obj'Address (see Unaligned_Valid routine in Fat_Gen).
4409 if Is_Possibly_Unaligned_Object (Pref) then
4410 Expand_Fpt_Attribute
4411 (N, Pkg, Name_Unaligned_Valid,
4413 Make_Attribute_Reference (Loc,
4414 Prefix => Relocate_Node (Pref),
4415 Attribute_Name => Name_Address)));
4417 -- In the normal case where we are sure the object is
4418 -- aligned, we generate a call to Valid, and the argument in
4419 -- this case is obj'Unrestricted_Access (after converting
4420 -- obj to the right floating-point type).
4423 Expand_Fpt_Attribute
4424 (N, Pkg, Name_Valid,
4426 Make_Attribute_Reference (Loc,
4427 Prefix => Unchecked_Convert_To (Ftp, Pref),
4428 Attribute_Name => Name_Unrestricted_Access)));
4432 -- One more task, we still need a range check. Required
4433 -- only if we have a constraint, since the Valid routine
4434 -- catches infinities properly (infinities are never valid).
4436 -- The way we do the range check is simply to create the
4437 -- expression: Valid (N) and then Base_Type(Pref) in Typ.
4439 if not Subtypes_Statically_Match (Ptyp, Btyp) then
4442 Left_Opnd => Relocate_Node (N),
4445 Left_Opnd => Convert_To (Btyp, Pref),
4446 Right_Opnd => New_Occurrence_Of (Ptyp, Loc))));
4450 -- Enumeration type with holes
4452 -- For enumeration types with holes, the Pos value constructed by
4453 -- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a
4454 -- second argument of False returns minus one for an invalid value,
4455 -- and the non-negative pos value for a valid value, so the
4456 -- expansion of X'Valid is simply:
4458 -- type(X)'Pos (X) >= 0
4460 -- We can't quite generate it that way because of the requirement
4461 -- for the non-standard second argument of False in the resulting
4462 -- rep_to_pos call, so we have to explicitly create:
4464 -- _rep_to_pos (X, False) >= 0
4466 -- If we have an enumeration subtype, we also check that the
4467 -- value is in range:
4469 -- _rep_to_pos (X, False) >= 0
4471 -- (X >= type(X)'First and then type(X)'Last <= X)
4473 elsif Is_Enumeration_Type (Ptyp)
4474 and then Present (Enum_Pos_To_Rep (Base_Type (Ptyp)))
4479 Make_Function_Call (Loc,
4482 (TSS (Base_Type (Ptyp), TSS_Rep_To_Pos), Loc),
4483 Parameter_Associations => New_List (
4485 New_Occurrence_Of (Standard_False, Loc))),
4486 Right_Opnd => Make_Integer_Literal (Loc, 0));
4490 (Type_Low_Bound (Ptyp) /= Type_Low_Bound (Btyp)
4492 Type_High_Bound (Ptyp) /= Type_High_Bound (Btyp))
4494 -- The call to Make_Range_Test will create declarations
4495 -- that need a proper insertion point, but Pref is now
4496 -- attached to a node with no ancestor. Attach to tree
4497 -- even if it is to be rewritten below.
4499 Set_Parent (Tst, Parent (N));
4503 Left_Opnd => Make_Range_Test,
4509 -- Fortran convention booleans
4511 -- For the very special case of Fortran convention booleans, the
4512 -- value is always valid, since it is an integer with the semantics
4513 -- that non-zero is true, and any value is permissible.
4515 elsif Is_Boolean_Type (Ptyp)
4516 and then Convention (Ptyp) = Convention_Fortran
4518 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
4520 -- For biased representations, we will be doing an unchecked
4521 -- conversion without unbiasing the result. That means that the range
4522 -- test has to take this into account, and the proper form of the
4525 -- Btyp!(Pref) < Btyp!(Ptyp'Range_Length)
4527 elsif Has_Biased_Representation (Ptyp) then
4528 Btyp := RTE (RE_Unsigned_32);
4532 Unchecked_Convert_To (Btyp, Duplicate_Subexpr (Pref)),
4534 Unchecked_Convert_To (Btyp,
4535 Make_Attribute_Reference (Loc,
4536 Prefix => New_Occurrence_Of (Ptyp, Loc),
4537 Attribute_Name => Name_Range_Length))));
4539 -- For all other scalar types, what we want logically is a
4542 -- X in type(X)'First .. type(X)'Last
4544 -- But that's precisely what won't work because of possible
4545 -- unwanted optimization (and indeed the basic motivation for
4546 -- the Valid attribute is exactly that this test does not work!)
4547 -- What will work is:
4549 -- Btyp!(X) >= Btyp!(type(X)'First)
4551 -- Btyp!(X) <= Btyp!(type(X)'Last)
4553 -- where Btyp is an integer type large enough to cover the full
4554 -- range of possible stored values (i.e. it is chosen on the basis
4555 -- of the size of the type, not the range of the values). We write
4556 -- this as two tests, rather than a range check, so that static
4557 -- evaluation will easily remove either or both of the checks if
4558 -- they can be -statically determined to be true (this happens
4559 -- when the type of X is static and the range extends to the full
4560 -- range of stored values).
4562 -- Unsigned types. Note: it is safe to consider only whether the
4563 -- subtype is unsigned, since we will in that case be doing all
4564 -- unsigned comparisons based on the subtype range. Since we use the
4565 -- actual subtype object size, this is appropriate.
4567 -- For example, if we have
4569 -- subtype x is integer range 1 .. 200;
4570 -- for x'Object_Size use 8;
4572 -- Now the base type is signed, but objects of this type are bits
4573 -- unsigned, and doing an unsigned test of the range 1 to 200 is
4574 -- correct, even though a value greater than 127 looks signed to a
4575 -- signed comparison.
4577 elsif Is_Unsigned_Type (Ptyp) then
4578 if Esize (Ptyp) <= 32 then
4579 Btyp := RTE (RE_Unsigned_32);
4581 Btyp := RTE (RE_Unsigned_64);
4584 Rewrite (N, Make_Range_Test);
4589 if Esize (Ptyp) <= Esize (Standard_Integer) then
4590 Btyp := Standard_Integer;
4592 Btyp := Universal_Integer;
4595 Rewrite (N, Make_Range_Test);
4598 Analyze_And_Resolve (N, Standard_Boolean);
4599 Validity_Checks_On := Save_Validity_Checks_On;
4606 -- Value attribute is handled in separate unti Exp_Imgv
4608 when Attribute_Value =>
4609 Exp_Imgv.Expand_Value_Attribute (N);
4615 -- The processing for Value_Size shares the processing for Size
4621 -- The processing for Version shares the processing for Body_Version
4627 -- Wide_Image attribute is handled in separate unit Exp_Imgv
4629 when Attribute_Wide_Image =>
4630 Exp_Imgv.Expand_Wide_Image_Attribute (N);
4632 ---------------------
4633 -- Wide_Wide_Image --
4634 ---------------------
4636 -- Wide_Wide_Image attribute is handled in separate unit Exp_Imgv
4638 when Attribute_Wide_Wide_Image =>
4639 Exp_Imgv.Expand_Wide_Wide_Image_Attribute (N);
4645 -- We expand typ'Wide_Value (X) into
4648 -- (Wide_String_To_String (X, Wide_Character_Encoding_Method))
4650 -- Wide_String_To_String is a runtime function that converts its wide
4651 -- string argument to String, converting any non-translatable characters
4652 -- into appropriate escape sequences. This preserves the required
4653 -- semantics of Wide_Value in all cases, and results in a very simple
4654 -- implementation approach.
4656 -- Note: for this approach to be fully standard compliant for the cases
4657 -- where typ is Wide_Character and Wide_Wide_Character, the encoding
4658 -- method must cover the entire character range (e.g. UTF-8). But that
4659 -- is a reasonable requirement when dealing with encoded character
4660 -- sequences. Presumably if one of the restrictive encoding mechanisms
4661 -- is in use such as Shift-JIS, then characters that cannot be
4662 -- represented using this encoding will not appear in any case.
4664 when Attribute_Wide_Value => Wide_Value :
4667 Make_Attribute_Reference (Loc,
4669 Attribute_Name => Name_Value,
4671 Expressions => New_List (
4672 Make_Function_Call (Loc,
4674 New_Reference_To (RTE (RE_Wide_String_To_String), Loc),
4676 Parameter_Associations => New_List (
4677 Relocate_Node (First (Exprs)),
4678 Make_Integer_Literal (Loc,
4679 Intval => Int (Wide_Character_Encoding_Method)))))));
4681 Analyze_And_Resolve (N, Typ);
4684 ---------------------
4685 -- Wide_Wide_Value --
4686 ---------------------
4688 -- We expand typ'Wide_Value_Value (X) into
4691 -- (Wide_Wide_String_To_String (X, Wide_Character_Encoding_Method))
4693 -- Wide_Wide_String_To_String is a runtime function that converts its
4694 -- wide string argument to String, converting any non-translatable
4695 -- characters into appropriate escape sequences. This preserves the
4696 -- required semantics of Wide_Wide_Value in all cases, and results in a
4697 -- very simple implementation approach.
4699 -- It's not quite right where typ = Wide_Wide_Character, because the
4700 -- encoding method may not cover the whole character type ???
4702 when Attribute_Wide_Wide_Value => Wide_Wide_Value :
4705 Make_Attribute_Reference (Loc,
4707 Attribute_Name => Name_Value,
4709 Expressions => New_List (
4710 Make_Function_Call (Loc,
4712 New_Reference_To (RTE (RE_Wide_Wide_String_To_String), Loc),
4714 Parameter_Associations => New_List (
4715 Relocate_Node (First (Exprs)),
4716 Make_Integer_Literal (Loc,
4717 Intval => Int (Wide_Character_Encoding_Method)))))));
4719 Analyze_And_Resolve (N, Typ);
4720 end Wide_Wide_Value;
4722 ---------------------
4723 -- Wide_Wide_Width --
4724 ---------------------
4726 -- Wide_Wide_Width attribute is handled in separate unit Exp_Imgv
4728 when Attribute_Wide_Wide_Width =>
4729 Exp_Imgv.Expand_Width_Attribute (N, Wide_Wide);
4735 -- Wide_Width attribute is handled in separate unit Exp_Imgv
4737 when Attribute_Wide_Width =>
4738 Exp_Imgv.Expand_Width_Attribute (N, Wide);
4744 -- Width attribute is handled in separate unit Exp_Imgv
4746 when Attribute_Width =>
4747 Exp_Imgv.Expand_Width_Attribute (N, Normal);
4753 when Attribute_Write => Write : declare
4754 P_Type : constant Entity_Id := Entity (Pref);
4755 U_Type : constant Entity_Id := Underlying_Type (P_Type);
4763 -- If no underlying type, we have an error that will be diagnosed
4764 -- elsewhere, so here we just completely ignore the expansion.
4770 -- The simple case, if there is a TSS for Write, just call it
4772 Pname := Find_Stream_Subprogram (P_Type, TSS_Stream_Write);
4774 if Present (Pname) then
4778 -- If there is a Stream_Convert pragma, use it, we rewrite
4780 -- sourcetyp'Output (stream, Item)
4784 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
4786 -- where strmwrite is the given Write function that converts an
4787 -- argument of type sourcetyp or a type acctyp, from which it is
4788 -- derived to type strmtyp. The conversion to acttyp is required
4789 -- for the derived case.
4791 Prag := Get_Stream_Convert_Pragma (P_Type);
4793 if Present (Prag) then
4795 Next (Next (First (Pragma_Argument_Associations (Prag))));
4796 Wfunc := Entity (Expression (Arg3));
4799 Make_Attribute_Reference (Loc,
4800 Prefix => New_Occurrence_Of (Etype (Wfunc), Loc),
4801 Attribute_Name => Name_Output,
4802 Expressions => New_List (
4803 Relocate_Node (First (Exprs)),
4804 Make_Function_Call (Loc,
4805 Name => New_Occurrence_Of (Wfunc, Loc),
4806 Parameter_Associations => New_List (
4807 OK_Convert_To (Etype (First_Formal (Wfunc)),
4808 Relocate_Node (Next (First (Exprs)))))))));
4813 -- For elementary types, we call the W_xxx routine directly
4815 elsif Is_Elementary_Type (U_Type) then
4816 Rewrite (N, Build_Elementary_Write_Call (N));
4822 elsif Is_Array_Type (U_Type) then
4823 Build_Array_Write_Procedure (N, U_Type, Decl, Pname);
4824 Compile_Stream_Body_In_Scope (N, Decl, U_Type, Check => False);
4826 -- Tagged type case, use the primitive Write function. Note that
4827 -- this will dispatch in the class-wide case which is what we want
4829 elsif Is_Tagged_Type (U_Type) then
4830 Pname := Find_Prim_Op (U_Type, TSS_Stream_Write);
4832 -- All other record type cases, including protected records.
4833 -- The latter only arise for expander generated code for
4834 -- handling shared passive partition access.
4838 (Is_Record_Type (U_Type) or else Is_Protected_Type (U_Type));
4840 -- Ada 2005 (AI-216): Program_Error is raised when executing
4841 -- the default implementation of the Write attribute of an
4842 -- Unchecked_Union type. However, if the 'Write reference is
4843 -- within the generated Output stream procedure, Write outputs
4844 -- the components, and the default values of the discriminant
4845 -- are streamed by the Output procedure itself.
4847 if Is_Unchecked_Union (Base_Type (U_Type))
4848 and not Is_TSS (Current_Scope, TSS_Stream_Output)
4851 Make_Raise_Program_Error (Loc,
4852 Reason => PE_Unchecked_Union_Restriction));
4855 if Has_Discriminants (U_Type)
4857 (Discriminant_Default_Value (First_Discriminant (U_Type)))
4859 Build_Mutable_Record_Write_Procedure
4860 (Loc, Base_Type (U_Type), Decl, Pname);
4862 Build_Record_Write_Procedure
4863 (Loc, Base_Type (U_Type), Decl, Pname);
4866 Insert_Action (N, Decl);
4870 -- If we fall through, Pname is the procedure to be called
4872 Rewrite_Stream_Proc_Call (Pname);
4875 -- Component_Size is handled by Gigi, unless the component size is known
4876 -- at compile time, which is always true in the packed array case. It is
4877 -- important that the packed array case is handled in the front end (see
4878 -- Eval_Attribute) since Gigi would otherwise get confused by the
4879 -- equivalent packed array type.
4881 when Attribute_Component_Size =>
4884 -- The following attributes are handled by the back end (except that
4885 -- static cases have already been evaluated during semantic processing,
4886 -- but in any case the back end should not count on this). The one bit
4887 -- of special processing required is that these attributes typically
4888 -- generate conditionals in the code, so we need to check the relevant
4891 when Attribute_Max |
4893 Check_Restriction (No_Implicit_Conditionals, N);
4895 -- The following attributes are handled by the back end (except that
4896 -- static cases have already been evaluated during semantic processing,
4897 -- but in any case the back end should not count on this).
4899 -- Gigi also handles the non-class-wide cases of Size
4901 when Attribute_Bit_Order |
4902 Attribute_Code_Address |
4903 Attribute_Definite |
4904 Attribute_Null_Parameter |
4905 Attribute_Passed_By_Reference |
4906 Attribute_Pool_Address =>
4909 -- The following attributes are also handled by Gigi, but return a
4910 -- universal integer result, so may need a conversion for checking
4911 -- that the result is in range.
4913 when Attribute_Aft |
4915 Attribute_Max_Size_In_Storage_Elements
4917 Apply_Universal_Integer_Attribute_Checks (N);
4919 -- The following attributes should not appear at this stage, since they
4920 -- have already been handled by the analyzer (and properly rewritten
4921 -- with corresponding values or entities to represent the right values)
4923 when Attribute_Abort_Signal |
4924 Attribute_Address_Size |
4927 Attribute_Default_Bit_Order |
4934 Attribute_Fast_Math |
4935 Attribute_Has_Access_Values |
4936 Attribute_Has_Discriminants |
4938 Attribute_Machine_Emax |
4939 Attribute_Machine_Emin |
4940 Attribute_Machine_Mantissa |
4941 Attribute_Machine_Overflows |
4942 Attribute_Machine_Radix |
4943 Attribute_Machine_Rounds |
4944 Attribute_Maximum_Alignment |
4945 Attribute_Model_Emin |
4946 Attribute_Model_Epsilon |
4947 Attribute_Model_Mantissa |
4948 Attribute_Model_Small |
4950 Attribute_Partition_ID |
4952 Attribute_Safe_Emax |
4953 Attribute_Safe_First |
4954 Attribute_Safe_Large |
4955 Attribute_Safe_Last |
4956 Attribute_Safe_Small |
4958 Attribute_Signed_Zeros |
4960 Attribute_Storage_Unit |
4961 Attribute_Stub_Type |
4962 Attribute_Target_Name |
4963 Attribute_Type_Class |
4964 Attribute_Unconstrained_Array |
4965 Attribute_Universal_Literal_String |
4966 Attribute_Wchar_T_Size |
4967 Attribute_Word_Size =>
4969 raise Program_Error;
4971 -- The Asm_Input and Asm_Output attributes are not expanded at this
4972 -- stage, but will be eliminated in the expansion of the Asm call,
4973 -- see Exp_Intr for details. So Gigi will never see these either.
4975 when Attribute_Asm_Input |
4976 Attribute_Asm_Output =>
4983 when RE_Not_Available =>
4985 end Expand_N_Attribute_Reference;
4987 ----------------------
4988 -- Expand_Pred_Succ --
4989 ----------------------
4991 -- For typ'Pred (exp), we generate the check
4993 -- [constraint_error when exp = typ'Base'First]
4995 -- Similarly, for typ'Succ (exp), we generate the check
4997 -- [constraint_error when exp = typ'Base'Last]
4999 -- These checks are not generated for modular types, since the proper
5000 -- semantics for Succ and Pred on modular types is to wrap, not raise CE.
5002 procedure Expand_Pred_Succ (N : Node_Id) is
5003 Loc : constant Source_Ptr := Sloc (N);
5007 if Attribute_Name (N) = Name_Pred then
5014 Make_Raise_Constraint_Error (Loc,
5018 Duplicate_Subexpr_Move_Checks (First (Expressions (N))),
5020 Make_Attribute_Reference (Loc,
5022 New_Reference_To (Base_Type (Etype (Prefix (N))), Loc),
5023 Attribute_Name => Cnam)),
5024 Reason => CE_Overflow_Check_Failed));
5025 end Expand_Pred_Succ;
5031 procedure Find_Fat_Info
5033 Fat_Type : out Entity_Id;
5034 Fat_Pkg : out RE_Id)
5036 Btyp : constant Entity_Id := Base_Type (T);
5037 Rtyp : constant Entity_Id := Root_Type (T);
5038 Digs : constant Nat := UI_To_Int (Digits_Value (Btyp));
5041 -- If the base type is VAX float, then get appropriate VAX float type
5043 if Vax_Float (Btyp) then
5046 Fat_Type := RTE (RE_Fat_VAX_F);
5047 Fat_Pkg := RE_Attr_VAX_F_Float;
5050 Fat_Type := RTE (RE_Fat_VAX_D);
5051 Fat_Pkg := RE_Attr_VAX_D_Float;
5054 Fat_Type := RTE (RE_Fat_VAX_G);
5055 Fat_Pkg := RE_Attr_VAX_G_Float;
5058 raise Program_Error;
5061 -- If root type is VAX float, this is the case where the library has
5062 -- been recompiled in VAX float mode, and we have an IEEE float type.
5063 -- This is when we use the special IEEE Fat packages.
5065 elsif Vax_Float (Rtyp) then
5068 Fat_Type := RTE (RE_Fat_IEEE_Short);
5069 Fat_Pkg := RE_Attr_IEEE_Short;
5072 Fat_Type := RTE (RE_Fat_IEEE_Long);
5073 Fat_Pkg := RE_Attr_IEEE_Long;
5076 raise Program_Error;
5079 -- If neither the base type nor the root type is VAX_Float then VAX
5080 -- float is out of the picture, and we can just use the root type.
5085 if Fat_Type = Standard_Short_Float then
5086 Fat_Pkg := RE_Attr_Short_Float;
5088 elsif Fat_Type = Standard_Float then
5089 Fat_Pkg := RE_Attr_Float;
5091 elsif Fat_Type = Standard_Long_Float then
5092 Fat_Pkg := RE_Attr_Long_Float;
5094 elsif Fat_Type = Standard_Long_Long_Float then
5095 Fat_Pkg := RE_Attr_Long_Long_Float;
5097 -- Universal real (which is its own root type) is treated as being
5098 -- equivalent to Standard.Long_Long_Float, since it is defined to
5099 -- have the same precision as the longest Float type.
5101 elsif Fat_Type = Universal_Real then
5102 Fat_Type := Standard_Long_Long_Float;
5103 Fat_Pkg := RE_Attr_Long_Long_Float;
5106 raise Program_Error;
5111 ----------------------------
5112 -- Find_Stream_Subprogram --
5113 ----------------------------
5115 function Find_Stream_Subprogram
5117 Nam : TSS_Name_Type) return Entity_Id
5119 Ent : constant Entity_Id := TSS (Typ, Nam);
5121 if Present (Ent) then
5125 if Is_Tagged_Type (Typ)
5126 and then Is_Derived_Type (Typ)
5128 return Find_Prim_Op (Typ, Nam);
5130 return Find_Inherited_TSS (Typ, Nam);
5132 end Find_Stream_Subprogram;
5134 -----------------------
5135 -- Get_Index_Subtype --
5136 -----------------------
5138 function Get_Index_Subtype (N : Node_Id) return Node_Id is
5139 P_Type : Entity_Id := Etype (Prefix (N));
5144 if Is_Access_Type (P_Type) then
5145 P_Type := Designated_Type (P_Type);
5148 if No (Expressions (N)) then
5151 J := UI_To_Int (Expr_Value (First (Expressions (N))));
5154 Indx := First_Index (P_Type);
5160 return Etype (Indx);
5161 end Get_Index_Subtype;
5163 -------------------------------
5164 -- Get_Stream_Convert_Pragma --
5165 -------------------------------
5167 function Get_Stream_Convert_Pragma (T : Entity_Id) return Node_Id is
5172 -- Note: we cannot use Get_Rep_Pragma here because of the peculiarity
5173 -- that a stream convert pragma for a tagged type is not inherited from
5174 -- its parent. Probably what is wrong here is that it is basically
5175 -- incorrect to consider a stream convert pragma to be a representation
5176 -- pragma at all ???
5178 N := First_Rep_Item (Implementation_Base_Type (T));
5179 while Present (N) loop
5180 if Nkind (N) = N_Pragma and then Chars (N) = Name_Stream_Convert then
5182 -- For tagged types this pragma is not inherited, so we
5183 -- must verify that it is defined for the given type and
5187 Entity (Expression (First (Pragma_Argument_Associations (N))));
5189 if not Is_Tagged_Type (T)
5191 or else (Is_Private_Type (Typ) and then T = Full_View (Typ))
5201 end Get_Stream_Convert_Pragma;
5203 ---------------------------------
5204 -- Is_Constrained_Packed_Array --
5205 ---------------------------------
5207 function Is_Constrained_Packed_Array (Typ : Entity_Id) return Boolean is
5208 Arr : Entity_Id := Typ;
5211 if Is_Access_Type (Arr) then
5212 Arr := Designated_Type (Arr);
5215 return Is_Array_Type (Arr)
5216 and then Is_Constrained (Arr)
5217 and then Present (Packed_Array_Type (Arr));
5218 end Is_Constrained_Packed_Array;
5220 ----------------------------------------
5221 -- Is_Inline_Floating_Point_Attribute --
5222 ----------------------------------------
5224 function Is_Inline_Floating_Point_Attribute (N : Node_Id) return Boolean is
5225 Id : constant Attribute_Id := Get_Attribute_Id (Attribute_Name (N));
5228 if Nkind (Parent (N)) /= N_Type_Conversion
5229 or else not Is_Integer_Type (Etype (Parent (N)))
5234 -- Should also support 'Machine_Rounding and 'Unbiased_Rounding, but
5235 -- required back end support has not been implemented yet ???
5237 return Id = Attribute_Truncation;
5238 end Is_Inline_Floating_Point_Attribute;