1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. 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 COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Checks
; use Checks
;
28 with Einfo
; use Einfo
;
29 with Elists
; use Elists
;
30 with Exp_Atag
; use Exp_Atag
;
31 with Exp_Ch2
; use Exp_Ch2
;
32 with Exp_Ch3
; use Exp_Ch3
;
33 with Exp_Ch6
; use Exp_Ch6
;
34 with Exp_Ch9
; use Exp_Ch9
;
35 with Exp_Dist
; use Exp_Dist
;
36 with Exp_Imgv
; use Exp_Imgv
;
37 with Exp_Pakd
; use Exp_Pakd
;
38 with Exp_Strm
; use Exp_Strm
;
39 with Exp_Tss
; use Exp_Tss
;
40 with Exp_Util
; use Exp_Util
;
41 with Exp_VFpt
; use Exp_VFpt
;
42 with Fname
; use Fname
;
43 with Freeze
; use Freeze
;
44 with Gnatvsn
; use Gnatvsn
;
45 with Itypes
; use Itypes
;
47 with Namet
; use Namet
;
48 with Nmake
; use Nmake
;
49 with Nlists
; use Nlists
;
51 with Restrict
; use Restrict
;
52 with Rident
; use Rident
;
53 with Rtsfind
; use Rtsfind
;
55 with Sem_Aux
; use Sem_Aux
;
56 with Sem_Ch6
; use Sem_Ch6
;
57 with Sem_Ch7
; use Sem_Ch7
;
58 with Sem_Ch8
; use Sem_Ch8
;
59 with Sem_Eval
; use Sem_Eval
;
60 with Sem_Res
; use Sem_Res
;
61 with Sem_Util
; use Sem_Util
;
62 with Sinfo
; use Sinfo
;
63 with Snames
; use Snames
;
64 with Stand
; use Stand
;
65 with Stringt
; use Stringt
;
66 with Targparm
; use Targparm
;
67 with Tbuild
; use Tbuild
;
68 with Ttypes
; use Ttypes
;
69 with Uintp
; use Uintp
;
70 with Uname
; use Uname
;
71 with Validsw
; use Validsw
;
73 package body Exp_Attr
is
75 -----------------------
76 -- Local Subprograms --
77 -----------------------
79 procedure Compile_Stream_Body_In_Scope
84 -- The body for a stream subprogram may be generated outside of the scope
85 -- of the type. If the type is fully private, it may depend on the full
86 -- view of other types (e.g. indexes) that are currently private as well.
87 -- We install the declarations of the package in which the type is declared
88 -- before compiling the body in what is its proper environment. The Check
89 -- parameter indicates if checks are to be suppressed for the stream body.
90 -- We suppress checks for array/record reads, since the rule is that these
91 -- are like assignments, out of range values due to uninitialized storage,
92 -- or other invalid values do NOT cause a Constraint_Error to be raised.
94 procedure Expand_Access_To_Protected_Op
98 -- An attribute reference to a protected subprogram is transformed into
99 -- a pair of pointers: one to the object, and one to the operations.
100 -- This expansion is performed for 'Access and for 'Unrestricted_Access.
102 procedure Expand_Fpt_Attribute
107 -- This procedure expands a call to a floating-point attribute function.
108 -- N is the attribute reference node, and Args is a list of arguments to
109 -- be passed to the function call. Pkg identifies the package containing
110 -- the appropriate instantiation of System.Fat_Gen. Float arguments in Args
111 -- have already been converted to the floating-point type for which Pkg was
112 -- instantiated. The Nam argument is the relevant attribute processing
113 -- routine to be called. This is the same as the attribute name, except in
114 -- the Unaligned_Valid case.
116 procedure Expand_Fpt_Attribute_R
(N
: Node_Id
);
117 -- This procedure expands a call to a floating-point attribute function
118 -- that takes a single floating-point argument. The function to be called
119 -- is always the same as the attribute name.
121 procedure Expand_Fpt_Attribute_RI
(N
: Node_Id
);
122 -- This procedure expands a call to a floating-point attribute function
123 -- that takes one floating-point argument and one integer argument. The
124 -- function to be called is always the same as the attribute name.
126 procedure Expand_Fpt_Attribute_RR
(N
: Node_Id
);
127 -- This procedure expands a call to a floating-point attribute function
128 -- that takes two floating-point arguments. The function to be called
129 -- is always the same as the attribute name.
131 procedure Expand_Pred_Succ
(N
: Node_Id
);
132 -- Handles expansion of Pred or Succ attributes for case of non-real
133 -- operand with overflow checking required.
135 function Get_Index_Subtype
(N
: Node_Id
) return Entity_Id
;
136 -- Used for Last, Last, and Length, when the prefix is an array type.
137 -- Obtains the corresponding index subtype.
139 procedure Find_Fat_Info
141 Fat_Type
: out Entity_Id
;
142 Fat_Pkg
: out RE_Id
);
143 -- Given a floating-point type T, identifies the package containing the
144 -- attributes for this type (returned in Fat_Pkg), and the corresponding
145 -- type for which this package was instantiated from Fat_Gen. Error if T
146 -- is not a floating-point type.
148 function Find_Stream_Subprogram
150 Nam
: TSS_Name_Type
) return Entity_Id
;
151 -- Returns the stream-oriented subprogram attribute for Typ. For tagged
152 -- types, the corresponding primitive operation is looked up, else the
153 -- appropriate TSS from the type itself, or from its closest ancestor
154 -- defining it, is returned. In both cases, inheritance of representation
155 -- aspects is thus taken into account.
157 function Full_Base
(T
: Entity_Id
) return Entity_Id
;
158 -- The stream functions need to examine the underlying representation of
159 -- composite types. In some cases T may be non-private but its base type
160 -- is, in which case the function returns the corresponding full view.
162 function Get_Stream_Convert_Pragma
(T
: Entity_Id
) return Node_Id
;
163 -- Given a type, find a corresponding stream convert pragma that applies to
164 -- the implementation base type of this type (Typ). If found, return the
165 -- pragma node, otherwise return Empty if no pragma is found.
167 function Is_Constrained_Packed_Array
(Typ
: Entity_Id
) return Boolean;
168 -- Utility for array attributes, returns true on packed constrained
169 -- arrays, and on access to same.
171 function Is_Inline_Floating_Point_Attribute
(N
: Node_Id
) return Boolean;
172 -- Returns true iff the given node refers to an attribute call that
173 -- can be expanded directly by the back end and does not need front end
174 -- expansion. Typically used for rounding and truncation attributes that
175 -- appear directly inside a conversion to integer.
177 ----------------------------------
178 -- Compile_Stream_Body_In_Scope --
179 ----------------------------------
181 procedure Compile_Stream_Body_In_Scope
187 Installed
: Boolean := False;
188 Scop
: constant Entity_Id
:= Scope
(Arr
);
189 Curr
: constant Entity_Id
:= Current_Scope
;
193 and then not In_Open_Scopes
(Scop
)
194 and then Ekind
(Scop
) = E_Package
197 Install_Visible_Declarations
(Scop
);
198 Install_Private_Declarations
(Scop
);
201 -- The entities in the package are now visible, but the generated
202 -- stream entity must appear in the current scope (usually an
203 -- enclosing stream function) so that itypes all have their proper
210 Insert_Action
(N
, Decl
);
212 Insert_Action
(N
, Decl
, Suppress
=> All_Checks
);
217 -- Remove extra copy of current scope, and package itself
220 End_Package_Scope
(Scop
);
222 end Compile_Stream_Body_In_Scope
;
224 -----------------------------------
225 -- Expand_Access_To_Protected_Op --
226 -----------------------------------
228 procedure Expand_Access_To_Protected_Op
233 -- The value of the attribute_reference is a record containing two
234 -- fields: an access to the protected object, and an access to the
235 -- subprogram itself. The prefix is a selected component.
237 Loc
: constant Source_Ptr
:= Sloc
(N
);
239 Btyp
: constant Entity_Id
:= Base_Type
(Typ
);
242 E_T
: constant Entity_Id
:= Equivalent_Type
(Btyp
);
243 Acc
: constant Entity_Id
:=
244 Etype
(Next_Component
(First_Component
(E_T
)));
248 function May_Be_External_Call
return Boolean;
249 -- If the 'Access is to a local operation, but appears in a context
250 -- where it may lead to a call from outside the object, we must treat
251 -- this as an external call. Clearly we cannot tell without full
252 -- flow analysis, and a subsequent call that uses this 'Access may
253 -- lead to a bounded error (trying to seize locks twice, e.g.). For
254 -- now we treat 'Access as a potential external call if it is an actual
255 -- in a call to an outside subprogram.
257 --------------------------
258 -- May_Be_External_Call --
259 --------------------------
261 function May_Be_External_Call
return Boolean is
263 Par
: Node_Id
:= Parent
(N
);
266 -- Account for the case where the Access attribute is part of a
267 -- named parameter association.
269 if Nkind
(Par
) = N_Parameter_Association
then
273 if Nkind_In
(Par
, N_Procedure_Call_Statement
, N_Function_Call
)
274 and then Is_Entity_Name
(Name
(Par
))
276 Subp
:= Entity
(Name
(Par
));
277 return not In_Open_Scopes
(Scope
(Subp
));
281 end May_Be_External_Call
;
283 -- Start of processing for Expand_Access_To_Protected_Op
286 -- Within the body of the protected type, the prefix designates a local
287 -- operation, and the object is the first parameter of the corresponding
288 -- protected body of the current enclosing operation.
290 if Is_Entity_Name
(Pref
) then
291 if May_Be_External_Call
then
293 New_Occurrence_Of
(External_Subprogram
(Entity
(Pref
)), Loc
);
297 (Protected_Body_Subprogram
(Entity
(Pref
)), Loc
);
300 -- Don't traverse the scopes when the attribute occurs within an init
301 -- proc, because we directly use the _init formal of the init proc in
304 Curr
:= Current_Scope
;
305 if not Is_Init_Proc
(Curr
) then
306 pragma Assert
(In_Open_Scopes
(Scope
(Entity
(Pref
))));
308 while Scope
(Curr
) /= Scope
(Entity
(Pref
)) loop
309 Curr
:= Scope
(Curr
);
313 -- In case of protected entries the first formal of its Protected_
314 -- Body_Subprogram is the address of the object.
316 if Ekind
(Curr
) = E_Entry
then
320 (Protected_Body_Subprogram
(Curr
)), Loc
);
322 -- If the current scope is an init proc, then use the address of the
323 -- _init formal as the object reference.
325 elsif Is_Init_Proc
(Curr
) then
327 Make_Attribute_Reference
(Loc
,
328 Prefix
=> New_Occurrence_Of
(First_Formal
(Curr
), Loc
),
329 Attribute_Name
=> Name_Address
);
331 -- In case of protected subprograms the first formal of its
332 -- Protected_Body_Subprogram is the object and we get its address.
336 Make_Attribute_Reference
(Loc
,
340 (Protected_Body_Subprogram
(Curr
)), Loc
),
341 Attribute_Name
=> Name_Address
);
344 -- Case where the prefix is not an entity name. Find the
345 -- version of the protected operation to be called from
346 -- outside the protected object.
352 (Entity
(Selector_Name
(Pref
))), Loc
);
355 Make_Attribute_Reference
(Loc
,
356 Prefix
=> Relocate_Node
(Prefix
(Pref
)),
357 Attribute_Name
=> Name_Address
);
361 Make_Attribute_Reference
(Loc
,
363 Attribute_Name
=> Name_Access
);
365 -- We set the type of the access reference to the already generated
366 -- access_to_subprogram type, and declare the reference analyzed, to
367 -- prevent further expansion when the enclosing aggregate is analyzed.
369 Set_Etype
(Sub_Ref
, Acc
);
370 Set_Analyzed
(Sub_Ref
);
374 Expressions
=> New_List
(Obj_Ref
, Sub_Ref
));
376 -- Sub_Ref has been marked as analyzed, but we still need to make sure
377 -- Sub is correctly frozen.
379 Freeze_Before
(N
, Entity
(Sub
));
382 Analyze_And_Resolve
(N
, E_T
);
384 -- For subsequent analysis, the node must retain its type. The backend
385 -- will replace it with the equivalent type where needed.
388 end Expand_Access_To_Protected_Op
;
390 --------------------------
391 -- Expand_Fpt_Attribute --
392 --------------------------
394 procedure Expand_Fpt_Attribute
400 Loc
: constant Source_Ptr
:= Sloc
(N
);
401 Typ
: constant Entity_Id
:= Etype
(N
);
405 -- The function name is the selected component Attr_xxx.yyy where
406 -- Attr_xxx is the package name, and yyy is the argument Nam.
408 -- Note: it would be more usual to have separate RE entries for each
409 -- of the entities in the Fat packages, but first they have identical
410 -- names (so we would have to have lots of renaming declarations to
411 -- meet the normal RE rule of separate names for all runtime entities),
412 -- and second there would be an awful lot of them!
415 Make_Selected_Component
(Loc
,
416 Prefix
=> New_Reference_To
(RTE
(Pkg
), Loc
),
417 Selector_Name
=> Make_Identifier
(Loc
, Nam
));
419 -- The generated call is given the provided set of parameters, and then
420 -- wrapped in a conversion which converts the result to the target type
421 -- We use the base type as the target because a range check may be
425 Unchecked_Convert_To
(Base_Type
(Etype
(N
)),
426 Make_Function_Call
(Loc
,
428 Parameter_Associations
=> Args
)));
430 Analyze_And_Resolve
(N
, Typ
);
431 end Expand_Fpt_Attribute
;
433 ----------------------------
434 -- Expand_Fpt_Attribute_R --
435 ----------------------------
437 -- The single argument is converted to its root type to call the
438 -- appropriate runtime function, with the actual call being built
439 -- by Expand_Fpt_Attribute
441 procedure Expand_Fpt_Attribute_R
(N
: Node_Id
) is
442 E1
: constant Node_Id
:= First
(Expressions
(N
));
446 Find_Fat_Info
(Etype
(E1
), Ftp
, Pkg
);
448 (N
, Pkg
, Attribute_Name
(N
),
449 New_List
(Unchecked_Convert_To
(Ftp
, Relocate_Node
(E1
))));
450 end Expand_Fpt_Attribute_R
;
452 -----------------------------
453 -- Expand_Fpt_Attribute_RI --
454 -----------------------------
456 -- The first argument is converted to its root type and the second
457 -- argument is converted to standard long long integer to call the
458 -- appropriate runtime function, with the actual call being built
459 -- by Expand_Fpt_Attribute
461 procedure Expand_Fpt_Attribute_RI
(N
: Node_Id
) is
462 E1
: constant Node_Id
:= First
(Expressions
(N
));
465 E2
: constant Node_Id
:= Next
(E1
);
467 Find_Fat_Info
(Etype
(E1
), Ftp
, Pkg
);
469 (N
, Pkg
, Attribute_Name
(N
),
471 Unchecked_Convert_To
(Ftp
, Relocate_Node
(E1
)),
472 Unchecked_Convert_To
(Standard_Integer
, Relocate_Node
(E2
))));
473 end Expand_Fpt_Attribute_RI
;
475 -----------------------------
476 -- Expand_Fpt_Attribute_RR --
477 -----------------------------
479 -- The two arguments are converted to their root types to call the
480 -- appropriate runtime function, with the actual call being built
481 -- by Expand_Fpt_Attribute
483 procedure Expand_Fpt_Attribute_RR
(N
: Node_Id
) is
484 E1
: constant Node_Id
:= First
(Expressions
(N
));
487 E2
: constant Node_Id
:= Next
(E1
);
489 Find_Fat_Info
(Etype
(E1
), Ftp
, Pkg
);
491 (N
, Pkg
, Attribute_Name
(N
),
493 Unchecked_Convert_To
(Ftp
, Relocate_Node
(E1
)),
494 Unchecked_Convert_To
(Ftp
, Relocate_Node
(E2
))));
495 end Expand_Fpt_Attribute_RR
;
497 ----------------------------------
498 -- Expand_N_Attribute_Reference --
499 ----------------------------------
501 procedure Expand_N_Attribute_Reference
(N
: Node_Id
) is
502 Loc
: constant Source_Ptr
:= Sloc
(N
);
503 Typ
: constant Entity_Id
:= Etype
(N
);
504 Btyp
: constant Entity_Id
:= Base_Type
(Typ
);
505 Pref
: constant Node_Id
:= Prefix
(N
);
506 Ptyp
: constant Entity_Id
:= Etype
(Pref
);
507 Exprs
: constant List_Id
:= Expressions
(N
);
508 Id
: constant Attribute_Id
:= Get_Attribute_Id
(Attribute_Name
(N
));
510 procedure Rewrite_Stream_Proc_Call
(Pname
: Entity_Id
);
511 -- Rewrites a stream attribute for Read, Write or Output with the
512 -- procedure call. Pname is the entity for the procedure to call.
514 ------------------------------
515 -- Rewrite_Stream_Proc_Call --
516 ------------------------------
518 procedure Rewrite_Stream_Proc_Call
(Pname
: Entity_Id
) is
519 Item
: constant Node_Id
:= Next
(First
(Exprs
));
520 Formal
: constant Entity_Id
:= Next_Formal
(First_Formal
(Pname
));
521 Formal_Typ
: constant Entity_Id
:= Etype
(Formal
);
522 Is_Written
: constant Boolean := (Ekind
(Formal
) /= E_In_Parameter
);
525 -- The expansion depends on Item, the second actual, which is
526 -- the object being streamed in or out.
528 -- If the item is a component of a packed array type, and
529 -- a conversion is needed on exit, we introduce a temporary to
530 -- hold the value, because otherwise the packed reference will
531 -- not be properly expanded.
533 if Nkind
(Item
) = N_Indexed_Component
534 and then Is_Packed
(Base_Type
(Etype
(Prefix
(Item
))))
535 and then Base_Type
(Etype
(Item
)) /= Base_Type
(Formal_Typ
)
539 Temp
: constant Entity_Id
:= Make_Temporary
(Loc
, 'V');
545 Make_Object_Declaration
(Loc
,
546 Defining_Identifier
=> Temp
,
548 New_Occurrence_Of
(Formal_Typ
, Loc
));
549 Set_Etype
(Temp
, Formal_Typ
);
552 Make_Assignment_Statement
(Loc
,
553 Name
=> New_Copy_Tree
(Item
),
556 (Etype
(Item
), New_Occurrence_Of
(Temp
, Loc
)));
558 Rewrite
(Item
, New_Occurrence_Of
(Temp
, Loc
));
562 Make_Procedure_Call_Statement
(Loc
,
563 Name
=> New_Occurrence_Of
(Pname
, Loc
),
564 Parameter_Associations
=> Exprs
),
567 Rewrite
(N
, Make_Null_Statement
(Loc
));
572 -- For the class-wide dispatching cases, and for cases in which
573 -- the base type of the second argument matches the base type of
574 -- the corresponding formal parameter (that is to say the stream
575 -- operation is not inherited), we are all set, and can use the
576 -- argument unchanged.
578 -- For all other cases we do an unchecked conversion of the second
579 -- parameter to the type of the formal of the procedure we are
580 -- calling. This deals with the private type cases, and with going
581 -- to the root type as required in elementary type case.
583 if not Is_Class_Wide_Type
(Entity
(Pref
))
584 and then not Is_Class_Wide_Type
(Etype
(Item
))
585 and then Base_Type
(Etype
(Item
)) /= Base_Type
(Formal_Typ
)
588 Unchecked_Convert_To
(Formal_Typ
, Relocate_Node
(Item
)));
590 -- For untagged derived types set Assignment_OK, to prevent
591 -- copies from being created when the unchecked conversion
592 -- is expanded (which would happen in Remove_Side_Effects
593 -- if Expand_N_Unchecked_Conversion were allowed to call
594 -- Force_Evaluation). The copy could violate Ada semantics
595 -- in cases such as an actual that is an out parameter.
596 -- Note that this approach is also used in exp_ch7 for calls
597 -- to controlled type operations to prevent problems with
598 -- actuals wrapped in unchecked conversions.
600 if Is_Untagged_Derivation
(Etype
(Expression
(Item
))) then
601 Set_Assignment_OK
(Item
);
605 -- The stream operation to call maybe a renaming created by
606 -- an attribute definition clause, and may not be frozen yet.
607 -- Ensure that it has the necessary extra formals.
609 if not Is_Frozen
(Pname
) then
610 Create_Extra_Formals
(Pname
);
613 -- And now rewrite the call
616 Make_Procedure_Call_Statement
(Loc
,
617 Name
=> New_Occurrence_Of
(Pname
, Loc
),
618 Parameter_Associations
=> Exprs
));
621 end Rewrite_Stream_Proc_Call
;
623 -- Start of processing for Expand_N_Attribute_Reference
626 -- Do required validity checking, if enabled. Do not apply check to
627 -- output parameters of an Asm instruction, since the value of this
628 -- is not set till after the attribute has been elaborated, and do
629 -- not apply the check to the arguments of a 'Read or 'Input attribute
630 -- reference since the scalar argument is an OUT scalar.
632 if Validity_Checks_On
and then Validity_Check_Operands
633 and then Id
/= Attribute_Asm_Output
634 and then Id
/= Attribute_Read
635 and then Id
/= Attribute_Input
640 Expr
:= First
(Expressions
(N
));
641 while Present
(Expr
) loop
648 -- Ada 2005 (AI-318-02): If attribute prefix is a call to a build-in-
649 -- place function, then a temporary return object needs to be created
650 -- and access to it must be passed to the function. Currently we limit
651 -- such functions to those with inherently limited result subtypes, but
652 -- eventually we plan to expand the functions that are treated as
653 -- build-in-place to include other composite result types.
655 if Ada_Version
>= Ada_2005
656 and then Is_Build_In_Place_Function_Call
(Pref
)
658 Make_Build_In_Place_Call_In_Anonymous_Context
(Pref
);
661 -- If prefix is a protected type name, this is a reference to the
662 -- current instance of the type. For a component definition, nothing
663 -- to do (expansion will occur in the init proc). In other contexts,
664 -- rewrite into reference to current instance.
666 if Is_Protected_Self_Reference
(Pref
)
668 (Nkind_In
(Parent
(N
), N_Index_Or_Discriminant_Constraint
,
669 N_Discriminant_Association
)
670 and then Nkind
(Parent
(Parent
(Parent
(Parent
(N
))))) =
671 N_Component_Definition
)
673 Rewrite
(Pref
, Concurrent_Ref
(Pref
));
677 -- Remaining processing depends on specific attribute
681 -- Attributes related to Ada 2012 iterators (placeholder ???)
683 when Attribute_Constant_Indexing
=> null;
684 when Attribute_Default_Iterator
=> null;
685 when Attribute_Implicit_Dereference
=> null;
686 when Attribute_Iterator_Element
=> null;
687 when Attribute_Variable_Indexing
=> null;
693 when Attribute_Access |
694 Attribute_Unchecked_Access |
695 Attribute_Unrestricted_Access
=>
697 Access_Cases
: declare
698 Ref_Object
: constant Node_Id
:= Get_Referenced_Object
(Pref
);
699 Btyp_DDT
: Entity_Id
;
701 function Enclosing_Object
(N
: Node_Id
) return Node_Id
;
702 -- If N denotes a compound name (selected component, indexed
703 -- component, or slice), returns the name of the outermost such
704 -- enclosing object. Otherwise returns N. If the object is a
705 -- renaming, then the renamed object is returned.
707 ----------------------
708 -- Enclosing_Object --
709 ----------------------
711 function Enclosing_Object
(N
: Node_Id
) return Node_Id
is
716 while Nkind_In
(Obj_Name
, N_Selected_Component
,
720 Obj_Name
:= Prefix
(Obj_Name
);
723 return Get_Referenced_Object
(Obj_Name
);
724 end Enclosing_Object
;
726 -- Local declarations
728 Enc_Object
: constant Node_Id
:= Enclosing_Object
(Ref_Object
);
730 -- Start of processing for Access_Cases
733 Btyp_DDT
:= Designated_Type
(Btyp
);
735 -- Handle designated types that come from the limited view
737 if Ekind
(Btyp_DDT
) = E_Incomplete_Type
738 and then From_With_Type
(Btyp_DDT
)
739 and then Present
(Non_Limited_View
(Btyp_DDT
))
741 Btyp_DDT
:= Non_Limited_View
(Btyp_DDT
);
743 elsif Is_Class_Wide_Type
(Btyp_DDT
)
744 and then Ekind
(Etype
(Btyp_DDT
)) = E_Incomplete_Type
745 and then From_With_Type
(Etype
(Btyp_DDT
))
746 and then Present
(Non_Limited_View
(Etype
(Btyp_DDT
)))
747 and then Present
(Class_Wide_Type
748 (Non_Limited_View
(Etype
(Btyp_DDT
))))
751 Class_Wide_Type
(Non_Limited_View
(Etype
(Btyp_DDT
)));
754 -- In order to improve the text of error messages, the designated
755 -- type of access-to-subprogram itypes is set by the semantics as
756 -- the associated subprogram entity (see sem_attr). Now we replace
757 -- such node with the proper E_Subprogram_Type itype.
759 if Id
= Attribute_Unrestricted_Access
760 and then Is_Subprogram
(Directly_Designated_Type
(Typ
))
762 -- The following conditions ensure that this special management
763 -- is done only for "Address!(Prim'Unrestricted_Access)" nodes.
764 -- At this stage other cases in which the designated type is
765 -- still a subprogram (instead of an E_Subprogram_Type) are
766 -- wrong because the semantics must have overridden the type of
767 -- the node with the type imposed by the context.
769 if Nkind
(Parent
(N
)) = N_Unchecked_Type_Conversion
770 and then Etype
(Parent
(N
)) = RTE
(RE_Prim_Ptr
)
772 Set_Etype
(N
, RTE
(RE_Prim_Ptr
));
776 Subp
: constant Entity_Id
:=
777 Directly_Designated_Type
(Typ
);
779 Extra
: Entity_Id
:= Empty
;
780 New_Formal
: Entity_Id
;
781 Old_Formal
: Entity_Id
:= First_Formal
(Subp
);
782 Subp_Typ
: Entity_Id
;
785 Subp_Typ
:= Create_Itype
(E_Subprogram_Type
, N
);
786 Set_Etype
(Subp_Typ
, Etype
(Subp
));
787 Set_Returns_By_Ref
(Subp_Typ
, Returns_By_Ref
(Subp
));
789 if Present
(Old_Formal
) then
790 New_Formal
:= New_Copy
(Old_Formal
);
791 Set_First_Entity
(Subp_Typ
, New_Formal
);
794 Set_Scope
(New_Formal
, Subp_Typ
);
795 Etyp
:= Etype
(New_Formal
);
797 -- Handle itypes. There is no need to duplicate
798 -- here the itypes associated with record types
799 -- (i.e the implicit full view of private types).
802 and then Ekind
(Base_Type
(Etyp
)) /= E_Record_Type
804 Extra
:= New_Copy
(Etyp
);
805 Set_Parent
(Extra
, New_Formal
);
806 Set_Etype
(New_Formal
, Extra
);
807 Set_Scope
(Extra
, Subp_Typ
);
811 Next_Formal
(Old_Formal
);
812 exit when No
(Old_Formal
);
814 Set_Next_Entity
(New_Formal
,
815 New_Copy
(Old_Formal
));
816 Next_Entity
(New_Formal
);
819 Set_Next_Entity
(New_Formal
, Empty
);
820 Set_Last_Entity
(Subp_Typ
, Extra
);
823 -- Now that the explicit formals have been duplicated,
824 -- any extra formals needed by the subprogram must be
827 if Present
(Extra
) then
828 Set_Extra_Formal
(Extra
, Empty
);
831 Create_Extra_Formals
(Subp_Typ
);
832 Set_Directly_Designated_Type
(Typ
, Subp_Typ
);
837 if Is_Access_Protected_Subprogram_Type
(Btyp
) then
838 Expand_Access_To_Protected_Op
(N
, Pref
, Typ
);
840 -- If prefix is a type name, this is a reference to the current
841 -- instance of the type, within its initialization procedure.
843 elsif Is_Entity_Name
(Pref
)
844 and then Is_Type
(Entity
(Pref
))
851 -- If the current instance name denotes a task type, then
852 -- the access attribute is rewritten to be the name of the
853 -- "_task" parameter associated with the task type's task
854 -- procedure. An unchecked conversion is applied to ensure
855 -- a type match in cases of expander-generated calls (e.g.
858 if Is_Task_Type
(Entity
(Pref
)) then
860 First_Entity
(Get_Task_Body_Procedure
(Entity
(Pref
)));
861 while Present
(Formal
) loop
862 exit when Chars
(Formal
) = Name_uTask
;
863 Next_Entity
(Formal
);
866 pragma Assert
(Present
(Formal
));
869 Unchecked_Convert_To
(Typ
,
870 New_Occurrence_Of
(Formal
, Loc
)));
873 -- The expression must appear in a default expression,
874 -- (which in the initialization procedure is the
875 -- right-hand side of an assignment), and not in a
876 -- discriminant constraint.
880 while Present
(Par
) loop
881 exit when Nkind
(Par
) = N_Assignment_Statement
;
883 if Nkind
(Par
) = N_Component_Declaration
then
890 if Present
(Par
) then
892 Make_Attribute_Reference
(Loc
,
893 Prefix
=> Make_Identifier
(Loc
, Name_uInit
),
894 Attribute_Name
=> Attribute_Name
(N
)));
896 Analyze_And_Resolve
(N
, Typ
);
901 -- If the prefix of an Access attribute is a dereference of an
902 -- access parameter (or a renaming of such a dereference, or a
903 -- subcomponent of such a dereference) and the context is a
904 -- general access type (including the type of an object or
905 -- component with an access_definition, but not the anonymous
906 -- type of an access parameter or access discriminant), then
907 -- apply an accessibility check to the access parameter. We used
908 -- to rewrite the access parameter as a type conversion, but that
909 -- could only be done if the immediate prefix of the Access
910 -- attribute was the dereference, and didn't handle cases where
911 -- the attribute is applied to a subcomponent of the dereference,
912 -- since there's generally no available, appropriate access type
913 -- to convert to in that case. The attribute is passed as the
914 -- point to insert the check, because the access parameter may
915 -- come from a renaming, possibly in a different scope, and the
916 -- check must be associated with the attribute itself.
918 elsif Id
= Attribute_Access
919 and then Nkind
(Enc_Object
) = N_Explicit_Dereference
920 and then Is_Entity_Name
(Prefix
(Enc_Object
))
921 and then (Ekind
(Btyp
) = E_General_Access_Type
922 or else Is_Local_Anonymous_Access
(Btyp
))
923 and then Ekind
(Entity
(Prefix
(Enc_Object
))) in Formal_Kind
924 and then Ekind
(Etype
(Entity
(Prefix
(Enc_Object
))))
925 = E_Anonymous_Access_Type
926 and then Present
(Extra_Accessibility
927 (Entity
(Prefix
(Enc_Object
))))
929 Apply_Accessibility_Check
(Prefix
(Enc_Object
), Typ
, N
);
931 -- Ada 2005 (AI-251): If the designated type is an interface we
932 -- add an implicit conversion to force the displacement of the
933 -- pointer to reference the secondary dispatch table.
935 elsif Is_Interface
(Btyp_DDT
)
936 and then (Comes_From_Source
(N
)
937 or else Comes_From_Source
(Ref_Object
)
938 or else (Nkind
(Ref_Object
) in N_Has_Chars
939 and then Chars
(Ref_Object
) = Name_uInit
))
941 if Nkind
(Ref_Object
) /= N_Explicit_Dereference
then
943 -- No implicit conversion required if types match, or if
944 -- the prefix is the class_wide_type of the interface. In
945 -- either case passing an object of the interface type has
946 -- already set the pointer correctly.
948 if Btyp_DDT
= Etype
(Ref_Object
)
949 or else (Is_Class_Wide_Type
(Etype
(Ref_Object
))
951 Class_Wide_Type
(Btyp_DDT
) = Etype
(Ref_Object
))
957 Convert_To
(Btyp_DDT
,
958 New_Copy_Tree
(Prefix
(N
))));
960 Analyze_And_Resolve
(Prefix
(N
), Btyp_DDT
);
963 -- When the object is an explicit dereference, convert the
964 -- dereference's prefix.
968 Obj_DDT
: constant Entity_Id
:=
970 (Directly_Designated_Type
971 (Etype
(Prefix
(Ref_Object
))));
973 -- No implicit conversion required if designated types
974 -- match, or if we have an unrestricted access.
976 if Obj_DDT
/= Btyp_DDT
977 and then Id
/= Attribute_Unrestricted_Access
978 and then not (Is_Class_Wide_Type
(Obj_DDT
)
979 and then Etype
(Obj_DDT
) = Btyp_DDT
)
983 New_Copy_Tree
(Prefix
(Ref_Object
))));
984 Analyze_And_Resolve
(N
, Typ
);
995 -- Transforms 'Adjacent into a call to the floating-point attribute
996 -- function Adjacent in Fat_xxx (where xxx is the root type)
998 when Attribute_Adjacent
=>
999 Expand_Fpt_Attribute_RR
(N
);
1005 when Attribute_Address
=> Address
: declare
1006 Task_Proc
: Entity_Id
;
1009 -- If the prefix is a task or a task type, the useful address is that
1010 -- of the procedure for the task body, i.e. the actual program unit.
1011 -- We replace the original entity with that of the procedure.
1013 if Is_Entity_Name
(Pref
)
1014 and then Is_Task_Type
(Entity
(Pref
))
1016 Task_Proc
:= Next_Entity
(Root_Type
(Ptyp
));
1018 while Present
(Task_Proc
) loop
1019 exit when Ekind
(Task_Proc
) = E_Procedure
1020 and then Etype
(First_Formal
(Task_Proc
)) =
1021 Corresponding_Record_Type
(Ptyp
);
1022 Next_Entity
(Task_Proc
);
1025 if Present
(Task_Proc
) then
1026 Set_Entity
(Pref
, Task_Proc
);
1027 Set_Etype
(Pref
, Etype
(Task_Proc
));
1030 -- Similarly, the address of a protected operation is the address
1031 -- of the corresponding protected body, regardless of the protected
1032 -- object from which it is selected.
1034 elsif Nkind
(Pref
) = N_Selected_Component
1035 and then Is_Subprogram
(Entity
(Selector_Name
(Pref
)))
1036 and then Is_Protected_Type
(Scope
(Entity
(Selector_Name
(Pref
))))
1040 External_Subprogram
(Entity
(Selector_Name
(Pref
))), Loc
));
1042 elsif Nkind
(Pref
) = N_Explicit_Dereference
1043 and then Ekind
(Ptyp
) = E_Subprogram_Type
1044 and then Convention
(Ptyp
) = Convention_Protected
1046 -- The prefix is be a dereference of an access_to_protected_
1047 -- subprogram. The desired address is the second component of
1048 -- the record that represents the access.
1051 Addr
: constant Entity_Id
:= Etype
(N
);
1052 Ptr
: constant Node_Id
:= Prefix
(Pref
);
1053 T
: constant Entity_Id
:=
1054 Equivalent_Type
(Base_Type
(Etype
(Ptr
)));
1058 Unchecked_Convert_To
(Addr
,
1059 Make_Selected_Component
(Loc
,
1060 Prefix
=> Unchecked_Convert_To
(T
, Ptr
),
1061 Selector_Name
=> New_Occurrence_Of
(
1062 Next_Entity
(First_Entity
(T
)), Loc
))));
1064 Analyze_And_Resolve
(N
, Addr
);
1067 -- Ada 2005 (AI-251): Class-wide interface objects are always
1068 -- "displaced" to reference the tag associated with the interface
1069 -- type. In order to obtain the real address of such objects we
1070 -- generate a call to a run-time subprogram that returns the base
1071 -- address of the object.
1073 -- This processing is not needed in the VM case, where dispatching
1074 -- issues are taken care of by the virtual machine.
1076 elsif Is_Class_Wide_Type
(Ptyp
)
1077 and then Is_Interface
(Ptyp
)
1078 and then Tagged_Type_Expansion
1079 and then not (Nkind
(Pref
) in N_Has_Entity
1080 and then Is_Subprogram
(Entity
(Pref
)))
1083 Make_Function_Call
(Loc
,
1084 Name
=> New_Reference_To
(RTE
(RE_Base_Address
), Loc
),
1085 Parameter_Associations
=> New_List
(
1086 Relocate_Node
(N
))));
1091 -- Deal with packed array reference, other cases are handled by
1094 if Involves_Packed_Array_Reference
(Pref
) then
1095 Expand_Packed_Address_Reference
(N
);
1103 when Attribute_Alignment
=> Alignment
: declare
1107 -- For class-wide types, X'Class'Alignment is transformed into a
1108 -- direct reference to the Alignment of the class type, so that the
1109 -- back end does not have to deal with the X'Class'Alignment
1112 if Is_Entity_Name
(Pref
)
1113 and then Is_Class_Wide_Type
(Entity
(Pref
))
1115 Rewrite
(Prefix
(N
), New_Occurrence_Of
(Entity
(Pref
), Loc
));
1118 -- For x'Alignment applied to an object of a class wide type,
1119 -- transform X'Alignment into a call to the predefined primitive
1120 -- operation _Alignment applied to X.
1122 elsif Is_Class_Wide_Type
(Ptyp
) then
1124 Make_Attribute_Reference
(Loc
,
1126 Attribute_Name
=> Name_Tag
);
1128 if VM_Target
= No_VM
then
1129 New_Node
:= Build_Get_Alignment
(Loc
, New_Node
);
1132 Make_Function_Call
(Loc
,
1133 Name
=> New_Reference_To
(RTE
(RE_Get_Alignment
), Loc
),
1134 Parameter_Associations
=> New_List
(New_Node
));
1137 -- Case where the context is a specific integer type with which
1138 -- the original attribute was compatible. The function has a
1139 -- specific type as well, so to preserve the compatibility we
1140 -- must convert explicitly.
1142 if Typ
/= Standard_Integer
then
1143 New_Node
:= Convert_To
(Typ
, New_Node
);
1146 Rewrite
(N
, New_Node
);
1147 Analyze_And_Resolve
(N
, Typ
);
1150 -- For all other cases, we just have to deal with the case of
1151 -- the fact that the result can be universal.
1154 Apply_Universal_Integer_Attribute_Checks
(N
);
1162 when Attribute_AST_Entry
=> AST_Entry
: declare
1167 Entry_Ref
: Node_Id
;
1168 -- The reference to the entry or entry family
1171 -- The index expression for an entry family reference, or
1172 -- the Empty if Entry_Ref references a simple entry.
1175 if Nkind
(Pref
) = N_Indexed_Component
then
1176 Entry_Ref
:= Prefix
(Pref
);
1177 Index
:= First
(Expressions
(Pref
));
1183 -- Get expression for Task_Id and the entry entity
1185 if Nkind
(Entry_Ref
) = N_Selected_Component
then
1187 Make_Attribute_Reference
(Loc
,
1188 Attribute_Name
=> Name_Identity
,
1189 Prefix
=> Prefix
(Entry_Ref
));
1191 Ttyp
:= Etype
(Prefix
(Entry_Ref
));
1192 Eent
:= Entity
(Selector_Name
(Entry_Ref
));
1196 Make_Function_Call
(Loc
,
1197 Name
=> New_Occurrence_Of
(RTE
(RE_Current_Task
), Loc
));
1199 Eent
:= Entity
(Entry_Ref
);
1201 -- We have to find the enclosing task to get the task type
1202 -- There must be one, since we already validated this earlier
1204 Ttyp
:= Current_Scope
;
1205 while not Is_Task_Type
(Ttyp
) loop
1206 Ttyp
:= Scope
(Ttyp
);
1210 -- Now rewrite the attribute with a call to Create_AST_Handler
1213 Make_Function_Call
(Loc
,
1214 Name
=> New_Occurrence_Of
(RTE
(RE_Create_AST_Handler
), Loc
),
1215 Parameter_Associations
=> New_List
(
1217 Entry_Index_Expression
(Loc
, Eent
, Index
, Ttyp
))));
1219 Analyze_And_Resolve
(N
, RTE
(RE_AST_Handler
));
1226 -- We compute this if a packed array reference was present, otherwise we
1227 -- leave the computation up to the back end.
1229 when Attribute_Bit
=>
1230 if Involves_Packed_Array_Reference
(Pref
) then
1231 Expand_Packed_Bit_Reference
(N
);
1233 Apply_Universal_Integer_Attribute_Checks
(N
);
1240 -- We compute this if a component clause was present, otherwise we leave
1241 -- the computation up to the back end, since we don't know what layout
1244 -- Note that the attribute can apply to a naked record component
1245 -- in generated code (i.e. the prefix is an identifier that
1246 -- references the component or discriminant entity).
1248 when Attribute_Bit_Position
=> Bit_Position
: declare
1252 if Nkind
(Pref
) = N_Identifier
then
1253 CE
:= Entity
(Pref
);
1255 CE
:= Entity
(Selector_Name
(Pref
));
1258 if Known_Static_Component_Bit_Offset
(CE
) then
1260 Make_Integer_Literal
(Loc
,
1261 Intval
=> Component_Bit_Offset
(CE
)));
1262 Analyze_And_Resolve
(N
, Typ
);
1265 Apply_Universal_Integer_Attribute_Checks
(N
);
1273 -- A reference to P'Body_Version or P'Version is expanded to
1276 -- pragma Import (C, Vnn, "uuuuT");
1278 -- Get_Version_String (Vnn)
1280 -- where uuuu is the unit name (dots replaced by double underscore)
1281 -- and T is B for the cases of Body_Version, or Version applied to a
1282 -- subprogram acting as its own spec, and S for Version applied to a
1283 -- subprogram spec or package. This sequence of code references the
1284 -- unsigned constant created in the main program by the binder.
1286 -- A special exception occurs for Standard, where the string returned
1287 -- is a copy of the library string in gnatvsn.ads.
1289 when Attribute_Body_Version | Attribute_Version
=> Version
: declare
1290 E
: constant Entity_Id
:= Make_Temporary
(Loc
, 'V');
1295 -- If not library unit, get to containing library unit
1297 Pent
:= Entity
(Pref
);
1298 while Pent
/= Standard_Standard
1299 and then Scope
(Pent
) /= Standard_Standard
1300 and then not Is_Child_Unit
(Pent
)
1302 Pent
:= Scope
(Pent
);
1305 -- Special case Standard and Standard.ASCII
1307 if Pent
= Standard_Standard
or else Pent
= Standard_ASCII
then
1309 Make_String_Literal
(Loc
,
1310 Strval
=> Verbose_Library_Version
));
1315 -- Build required string constant
1317 Get_Name_String
(Get_Unit_Name
(Pent
));
1320 for J
in 1 .. Name_Len
- 2 loop
1321 if Name_Buffer
(J
) = '.' then
1322 Store_String_Chars
("__");
1324 Store_String_Char
(Get_Char_Code
(Name_Buffer
(J
)));
1328 -- Case of subprogram acting as its own spec, always use body
1330 if Nkind
(Declaration_Node
(Pent
)) in N_Subprogram_Specification
1331 and then Nkind
(Parent
(Declaration_Node
(Pent
))) =
1333 and then Acts_As_Spec
(Parent
(Declaration_Node
(Pent
)))
1335 Store_String_Chars
("B");
1337 -- Case of no body present, always use spec
1339 elsif not Unit_Requires_Body
(Pent
) then
1340 Store_String_Chars
("S");
1342 -- Otherwise use B for Body_Version, S for spec
1344 elsif Id
= Attribute_Body_Version
then
1345 Store_String_Chars
("B");
1347 Store_String_Chars
("S");
1351 Lib
.Version_Referenced
(S
);
1353 -- Insert the object declaration
1355 Insert_Actions
(N
, New_List
(
1356 Make_Object_Declaration
(Loc
,
1357 Defining_Identifier
=> E
,
1358 Object_Definition
=>
1359 New_Occurrence_Of
(RTE
(RE_Unsigned
), Loc
))));
1361 -- Set entity as imported with correct external name
1363 Set_Is_Imported
(E
);
1364 Set_Interface_Name
(E
, Make_String_Literal
(Loc
, S
));
1366 -- Set entity as internal to ensure proper Sprint output of its
1367 -- implicit importation.
1369 Set_Is_Internal
(E
);
1371 -- And now rewrite original reference
1374 Make_Function_Call
(Loc
,
1375 Name
=> New_Reference_To
(RTE
(RE_Get_Version_String
), Loc
),
1376 Parameter_Associations
=> New_List
(
1377 New_Occurrence_Of
(E
, Loc
))));
1380 Analyze_And_Resolve
(N
, RTE
(RE_Version_String
));
1387 -- Transforms 'Ceiling into a call to the floating-point attribute
1388 -- function Ceiling in Fat_xxx (where xxx is the root type)
1390 when Attribute_Ceiling
=>
1391 Expand_Fpt_Attribute_R
(N
);
1397 -- Transforms 'Callable attribute into a call to the Callable function
1399 when Attribute_Callable
=> Callable
:
1401 -- We have an object of a task interface class-wide type as a prefix
1402 -- to Callable. Generate:
1403 -- callable (Task_Id (Pref._disp_get_task_id));
1405 if Ada_Version
>= Ada_2005
1406 and then Ekind
(Ptyp
) = E_Class_Wide_Type
1407 and then Is_Interface
(Ptyp
)
1408 and then Is_Task_Interface
(Ptyp
)
1411 Make_Function_Call
(Loc
,
1413 New_Reference_To
(RTE
(RE_Callable
), Loc
),
1414 Parameter_Associations
=> New_List
(
1415 Make_Unchecked_Type_Conversion
(Loc
,
1417 New_Reference_To
(RTE
(RO_ST_Task_Id
), Loc
),
1419 Make_Selected_Component
(Loc
,
1421 New_Copy_Tree
(Pref
),
1423 Make_Identifier
(Loc
, Name_uDisp_Get_Task_Id
))))));
1427 Build_Call_With_Task
(Pref
, RTE
(RE_Callable
)));
1430 Analyze_And_Resolve
(N
, Standard_Boolean
);
1437 -- Transforms 'Caller attribute into a call to either the
1438 -- Task_Entry_Caller or the Protected_Entry_Caller function.
1440 when Attribute_Caller
=> Caller
: declare
1441 Id_Kind
: constant Entity_Id
:= RTE
(RO_AT_Task_Id
);
1442 Ent
: constant Entity_Id
:= Entity
(Pref
);
1443 Conctype
: constant Entity_Id
:= Scope
(Ent
);
1444 Nest_Depth
: Integer := 0;
1451 if Is_Protected_Type
(Conctype
) then
1452 case Corresponding_Runtime_Package
(Conctype
) is
1453 when System_Tasking_Protected_Objects_Entries
=>
1456 (RTE
(RE_Protected_Entry_Caller
), Loc
);
1458 when System_Tasking_Protected_Objects_Single_Entry
=>
1461 (RTE
(RE_Protected_Single_Entry_Caller
), Loc
);
1464 raise Program_Error
;
1468 Unchecked_Convert_To
(Id_Kind
,
1469 Make_Function_Call
(Loc
,
1471 Parameter_Associations
=> New_List
(
1473 (Find_Protection_Object
(Current_Scope
), Loc
)))));
1478 -- Determine the nesting depth of the E'Caller attribute, that
1479 -- is, how many accept statements are nested within the accept
1480 -- statement for E at the point of E'Caller. The runtime uses
1481 -- this depth to find the specified entry call.
1483 for J
in reverse 0 .. Scope_Stack
.Last
loop
1484 S
:= Scope_Stack
.Table
(J
).Entity
;
1486 -- We should not reach the scope of the entry, as it should
1487 -- already have been checked in Sem_Attr that this attribute
1488 -- reference is within a matching accept statement.
1490 pragma Assert
(S
/= Conctype
);
1495 elsif Is_Entry
(S
) then
1496 Nest_Depth
:= Nest_Depth
+ 1;
1501 Unchecked_Convert_To
(Id_Kind
,
1502 Make_Function_Call
(Loc
,
1504 New_Reference_To
(RTE
(RE_Task_Entry_Caller
), Loc
),
1505 Parameter_Associations
=> New_List
(
1506 Make_Integer_Literal
(Loc
,
1507 Intval
=> Int
(Nest_Depth
))))));
1510 Analyze_And_Resolve
(N
, Id_Kind
);
1517 -- Transforms 'Compose into a call to the floating-point attribute
1518 -- function Compose in Fat_xxx (where xxx is the root type)
1520 -- Note: we strictly should have special code here to deal with the
1521 -- case of absurdly negative arguments (less than Integer'First)
1522 -- which will return a (signed) zero value, but it hardly seems
1523 -- worth the effort. Absurdly large positive arguments will raise
1524 -- constraint error which is fine.
1526 when Attribute_Compose
=>
1527 Expand_Fpt_Attribute_RI
(N
);
1533 when Attribute_Constrained
=> Constrained
: declare
1534 Formal_Ent
: constant Entity_Id
:= Param_Entity
(Pref
);
1536 function Is_Constrained_Aliased_View
(Obj
: Node_Id
) return Boolean;
1537 -- Ada 2005 (AI-363): Returns True if the object name Obj denotes a
1538 -- view of an aliased object whose subtype is constrained.
1540 ---------------------------------
1541 -- Is_Constrained_Aliased_View --
1542 ---------------------------------
1544 function Is_Constrained_Aliased_View
(Obj
: Node_Id
) return Boolean is
1548 if Is_Entity_Name
(Obj
) then
1551 if Present
(Renamed_Object
(E
)) then
1552 return Is_Constrained_Aliased_View
(Renamed_Object
(E
));
1554 return Is_Aliased
(E
) and then Is_Constrained
(Etype
(E
));
1558 return Is_Aliased_View
(Obj
)
1560 (Is_Constrained
(Etype
(Obj
))
1562 (Nkind
(Obj
) = N_Explicit_Dereference
1564 not Effectively_Has_Constrained_Partial_View
1565 (Typ
=> Base_Type
(Etype
(Obj
)),
1566 Scop
=> Current_Scope
)));
1568 end Is_Constrained_Aliased_View
;
1570 -- Start of processing for Constrained
1573 -- Reference to a parameter where the value is passed as an extra
1574 -- actual, corresponding to the extra formal referenced by the
1575 -- Extra_Constrained field of the corresponding formal. If this
1576 -- is an entry in-parameter, it is replaced by a constant renaming
1577 -- for which Extra_Constrained is never created.
1579 if Present
(Formal_Ent
)
1580 and then Ekind
(Formal_Ent
) /= E_Constant
1581 and then Present
(Extra_Constrained
(Formal_Ent
))
1585 (Extra_Constrained
(Formal_Ent
), Sloc
(N
)));
1587 -- For variables with a Extra_Constrained field, we use the
1588 -- corresponding entity.
1590 elsif Nkind
(Pref
) = N_Identifier
1591 and then Ekind
(Entity
(Pref
)) = E_Variable
1592 and then Present
(Extra_Constrained
(Entity
(Pref
)))
1596 (Extra_Constrained
(Entity
(Pref
)), Sloc
(N
)));
1598 -- For all other entity names, we can tell at compile time
1600 elsif Is_Entity_Name
(Pref
) then
1602 Ent
: constant Entity_Id
:= Entity
(Pref
);
1606 -- (RM J.4) obsolescent cases
1608 if Is_Type
(Ent
) then
1612 if Is_Private_Type
(Ent
) then
1613 Res
:= not Has_Discriminants
(Ent
)
1614 or else Is_Constrained
(Ent
);
1616 -- It not a private type, must be a generic actual type
1617 -- that corresponded to a private type. We know that this
1618 -- correspondence holds, since otherwise the reference
1619 -- within the generic template would have been illegal.
1622 if Is_Composite_Type
(Underlying_Type
(Ent
)) then
1623 Res
:= Is_Constrained
(Ent
);
1629 -- If the prefix is not a variable or is aliased, then
1630 -- definitely true; if it's a formal parameter without an
1631 -- associated extra formal, then treat it as constrained.
1633 -- Ada 2005 (AI-363): An aliased prefix must be known to be
1634 -- constrained in order to set the attribute to True.
1636 elsif not Is_Variable
(Pref
)
1637 or else Present
(Formal_Ent
)
1638 or else (Ada_Version
< Ada_2005
1639 and then Is_Aliased_View
(Pref
))
1640 or else (Ada_Version
>= Ada_2005
1641 and then Is_Constrained_Aliased_View
(Pref
))
1645 -- Variable case, look at type to see if it is constrained.
1646 -- Note that the one case where this is not accurate (the
1647 -- procedure formal case), has been handled above.
1649 -- We use the Underlying_Type here (and below) in case the
1650 -- type is private without discriminants, but the full type
1651 -- has discriminants. This case is illegal, but we generate it
1652 -- internally for passing to the Extra_Constrained parameter.
1655 -- In Ada 2012, test for case of a limited tagged type, in
1656 -- which case the attribute is always required to return
1657 -- True. The underlying type is tested, to make sure we also
1658 -- return True for cases where there is an unconstrained
1659 -- object with an untagged limited partial view which has
1660 -- defaulted discriminants (such objects always produce a
1661 -- False in earlier versions of Ada). (Ada 2012: AI05-0214)
1663 Res
:= Is_Constrained
(Underlying_Type
(Etype
(Ent
)))
1665 (Ada_Version
>= Ada_2012
1666 and then Is_Tagged_Type
(Underlying_Type
(Ptyp
))
1667 and then Is_Limited_Type
(Ptyp
));
1670 Rewrite
(N
, New_Reference_To
(Boolean_Literals
(Res
), Loc
));
1673 -- Prefix is not an entity name. These are also cases where we can
1674 -- always tell at compile time by looking at the form and type of the
1675 -- prefix. If an explicit dereference of an object with constrained
1676 -- partial view, this is unconstrained (Ada 2005: AI95-0363). If the
1677 -- underlying type is a limited tagged type, then Constrained is
1678 -- required to always return True (Ada 2012: AI05-0214).
1684 not Is_Variable
(Pref
)
1686 (Nkind
(Pref
) = N_Explicit_Dereference
1688 not Effectively_Has_Constrained_Partial_View
1689 (Typ
=> Base_Type
(Ptyp
),
1690 Scop
=> Current_Scope
))
1691 or else Is_Constrained
(Underlying_Type
(Ptyp
))
1692 or else (Ada_Version
>= Ada_2012
1693 and then Is_Tagged_Type
(Underlying_Type
(Ptyp
))
1694 and then Is_Limited_Type
(Ptyp
))),
1698 Analyze_And_Resolve
(N
, Standard_Boolean
);
1705 -- Transforms 'Copy_Sign into a call to the floating-point attribute
1706 -- function Copy_Sign in Fat_xxx (where xxx is the root type)
1708 when Attribute_Copy_Sign
=>
1709 Expand_Fpt_Attribute_RR
(N
);
1715 -- Transforms 'Count attribute into a call to the Count function
1717 when Attribute_Count
=> Count
: declare
1719 Conctyp
: Entity_Id
;
1721 Entry_Id
: Entity_Id
;
1726 -- If the prefix is a member of an entry family, retrieve both
1727 -- entry name and index. For a simple entry there is no index.
1729 if Nkind
(Pref
) = N_Indexed_Component
then
1730 Entnam
:= Prefix
(Pref
);
1731 Index
:= First
(Expressions
(Pref
));
1737 Entry_Id
:= Entity
(Entnam
);
1739 -- Find the concurrent type in which this attribute is referenced
1740 -- (there had better be one).
1742 Conctyp
:= Current_Scope
;
1743 while not Is_Concurrent_Type
(Conctyp
) loop
1744 Conctyp
:= Scope
(Conctyp
);
1749 if Is_Protected_Type
(Conctyp
) then
1750 case Corresponding_Runtime_Package
(Conctyp
) is
1751 when System_Tasking_Protected_Objects_Entries
=>
1752 Name
:= New_Reference_To
(RTE
(RE_Protected_Count
), Loc
);
1755 Make_Function_Call
(Loc
,
1757 Parameter_Associations
=> New_List
(
1759 (Find_Protection_Object
(Current_Scope
), Loc
),
1760 Entry_Index_Expression
1761 (Loc
, Entry_Id
, Index
, Scope
(Entry_Id
))));
1763 when System_Tasking_Protected_Objects_Single_Entry
=>
1765 New_Reference_To
(RTE
(RE_Protected_Count_Entry
), Loc
);
1768 Make_Function_Call
(Loc
,
1770 Parameter_Associations
=> New_List
(
1772 (Find_Protection_Object
(Current_Scope
), Loc
)));
1775 raise Program_Error
;
1782 Make_Function_Call
(Loc
,
1783 Name
=> New_Reference_To
(RTE
(RE_Task_Count
), Loc
),
1784 Parameter_Associations
=> New_List
(
1785 Entry_Index_Expression
(Loc
,
1786 Entry_Id
, Index
, Scope
(Entry_Id
))));
1789 -- The call returns type Natural but the context is universal integer
1790 -- so any integer type is allowed. The attribute was already resolved
1791 -- so its Etype is the required result type. If the base type of the
1792 -- context type is other than Standard.Integer we put in a conversion
1793 -- to the required type. This can be a normal typed conversion since
1794 -- both input and output types of the conversion are integer types
1796 if Base_Type
(Typ
) /= Base_Type
(Standard_Integer
) then
1797 Rewrite
(N
, Convert_To
(Typ
, Call
));
1802 Analyze_And_Resolve
(N
, Typ
);
1805 ---------------------
1806 -- Descriptor_Size --
1807 ---------------------
1809 when Attribute_Descriptor_Size
=>
1811 -- Attribute Descriptor_Size is handled by the back end when applied
1812 -- to an unconstrained array type.
1814 if Is_Array_Type
(Ptyp
)
1815 and then not Is_Constrained
(Ptyp
)
1817 Apply_Universal_Integer_Attribute_Checks
(N
);
1819 -- For any other type, the descriptor size is 0 because there is no
1820 -- actual descriptor, but the result is not formally static.
1823 Rewrite
(N
, Make_Integer_Literal
(Loc
, 0));
1825 Set_Is_Static_Expression
(N
, False);
1832 -- This processing is shared by Elab_Spec
1834 -- What we do is to insert the following declarations
1837 -- pragma Import (C, enn, "name___elabb/s");
1839 -- and then the Elab_Body/Spec attribute is replaced by a reference
1840 -- to this defining identifier.
1842 when Attribute_Elab_Body |
1843 Attribute_Elab_Spec
=>
1845 -- Leave attribute unexpanded in CodePeer mode: the gnat2scil
1846 -- back-end knows how to handle these attributes directly.
1848 if CodePeer_Mode
then
1853 Ent
: constant Entity_Id
:= Make_Temporary
(Loc
, 'E');
1857 procedure Make_Elab_String
(Nod
: Node_Id
);
1858 -- Given Nod, an identifier, or a selected component, put the
1859 -- image into the current string literal, with double underline
1860 -- between components.
1862 ----------------------
1863 -- Make_Elab_String --
1864 ----------------------
1866 procedure Make_Elab_String
(Nod
: Node_Id
) is
1868 if Nkind
(Nod
) = N_Selected_Component
then
1869 Make_Elab_String
(Prefix
(Nod
));
1873 Store_String_Char
('$');
1875 Store_String_Char
('.');
1877 Store_String_Char
('_');
1878 Store_String_Char
('_');
1881 Get_Name_String
(Chars
(Selector_Name
(Nod
)));
1884 pragma Assert
(Nkind
(Nod
) = N_Identifier
);
1885 Get_Name_String
(Chars
(Nod
));
1888 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
1889 end Make_Elab_String
;
1891 -- Start of processing for Elab_Body/Elab_Spec
1894 -- First we need to prepare the string literal for the name of
1895 -- the elaboration routine to be referenced.
1898 Make_Elab_String
(Pref
);
1900 if VM_Target
= No_VM
then
1901 Store_String_Chars
("___elab");
1902 Lang
:= Make_Identifier
(Loc
, Name_C
);
1904 Store_String_Chars
("._elab");
1905 Lang
:= Make_Identifier
(Loc
, Name_Ada
);
1908 if Id
= Attribute_Elab_Body
then
1909 Store_String_Char
('b');
1911 Store_String_Char
('s');
1916 Insert_Actions
(N
, New_List
(
1917 Make_Subprogram_Declaration
(Loc
,
1919 Make_Procedure_Specification
(Loc
,
1920 Defining_Unit_Name
=> Ent
)),
1923 Chars
=> Name_Import
,
1924 Pragma_Argument_Associations
=> New_List
(
1925 Make_Pragma_Argument_Association
(Loc
, Expression
=> Lang
),
1927 Make_Pragma_Argument_Association
(Loc
,
1928 Expression
=> Make_Identifier
(Loc
, Chars
(Ent
))),
1930 Make_Pragma_Argument_Association
(Loc
,
1931 Expression
=> Make_String_Literal
(Loc
, Str
))))));
1933 Set_Entity
(N
, Ent
);
1934 Rewrite
(N
, New_Occurrence_Of
(Ent
, Loc
));
1937 --------------------
1938 -- Elab_Subp_Body --
1939 --------------------
1941 -- Always ignored. In CodePeer mode, gnat2scil knows how to handle
1942 -- this attribute directly, and if we are not in CodePeer mode it is
1943 -- entirely ignored ???
1945 when Attribute_Elab_Subp_Body
=>
1952 -- Elaborated is always True for preelaborated units, predefined units,
1953 -- pure units and units which have Elaborate_Body pragmas. These units
1954 -- have no elaboration entity.
1956 -- Note: The Elaborated attribute is never passed to the back end
1958 when Attribute_Elaborated
=> Elaborated
: declare
1959 Ent
: constant Entity_Id
:= Entity
(Pref
);
1962 if Present
(Elaboration_Entity
(Ent
)) then
1966 New_Occurrence_Of
(Elaboration_Entity
(Ent
), Loc
),
1968 Make_Integer_Literal
(Loc
, Uint_0
)));
1969 Analyze_And_Resolve
(N
, Typ
);
1971 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
1979 when Attribute_Enum_Rep
=> Enum_Rep
:
1981 -- X'Enum_Rep (Y) expands to
1985 -- This is simply a direct conversion from the enumeration type to
1986 -- the target integer type, which is treated by the back end as a
1987 -- normal integer conversion, treating the enumeration type as an
1988 -- integer, which is exactly what we want! We set Conversion_OK to
1989 -- make sure that the analyzer does not complain about what otherwise
1990 -- might be an illegal conversion.
1992 if Is_Non_Empty_List
(Exprs
) then
1994 OK_Convert_To
(Typ
, Relocate_Node
(First
(Exprs
))));
1996 -- X'Enum_Rep where X is an enumeration literal is replaced by
1997 -- the literal value.
1999 elsif Ekind
(Entity
(Pref
)) = E_Enumeration_Literal
then
2001 Make_Integer_Literal
(Loc
, Enumeration_Rep
(Entity
(Pref
))));
2003 -- If this is a renaming of a literal, recover the representation
2006 elsif Ekind
(Entity
(Pref
)) = E_Constant
2007 and then Present
(Renamed_Object
(Entity
(Pref
)))
2009 Ekind
(Entity
(Renamed_Object
(Entity
(Pref
))))
2010 = E_Enumeration_Literal
2013 Make_Integer_Literal
(Loc
,
2014 Enumeration_Rep
(Entity
(Renamed_Object
(Entity
(Pref
))))));
2016 -- X'Enum_Rep where X is an object does a direct unchecked conversion
2017 -- of the object value, as described for the type case above.
2021 OK_Convert_To
(Typ
, Relocate_Node
(Pref
)));
2025 Analyze_And_Resolve
(N
, Typ
);
2032 when Attribute_Enum_Val
=> Enum_Val
: declare
2034 Btyp
: constant Entity_Id
:= Base_Type
(Ptyp
);
2037 -- X'Enum_Val (Y) expands to
2039 -- [constraint_error when _rep_to_pos (Y, False) = -1, msg]
2042 Expr
:= Unchecked_Convert_To
(Ptyp
, First
(Exprs
));
2045 Make_Raise_Constraint_Error
(Loc
,
2049 Make_Function_Call
(Loc
,
2051 New_Reference_To
(TSS
(Btyp
, TSS_Rep_To_Pos
), Loc
),
2052 Parameter_Associations
=> New_List
(
2053 Relocate_Node
(Duplicate_Subexpr
(Expr
)),
2054 New_Occurrence_Of
(Standard_False
, Loc
))),
2056 Right_Opnd
=> Make_Integer_Literal
(Loc
, -1)),
2057 Reason
=> CE_Range_Check_Failed
));
2060 Analyze_And_Resolve
(N
, Ptyp
);
2067 -- Transforms 'Exponent into a call to the floating-point attribute
2068 -- function Exponent in Fat_xxx (where xxx is the root type)
2070 when Attribute_Exponent
=>
2071 Expand_Fpt_Attribute_R
(N
);
2077 -- transforme X'External_Tag into Ada.Tags.External_Tag (X'tag)
2079 when Attribute_External_Tag
=> External_Tag
:
2082 Make_Function_Call
(Loc
,
2083 Name
=> New_Reference_To
(RTE
(RE_External_Tag
), Loc
),
2084 Parameter_Associations
=> New_List
(
2085 Make_Attribute_Reference
(Loc
,
2086 Attribute_Name
=> Name_Tag
,
2087 Prefix
=> Prefix
(N
)))));
2089 Analyze_And_Resolve
(N
, Standard_String
);
2096 when Attribute_First
=>
2098 -- If the prefix type is a constrained packed array type which
2099 -- already has a Packed_Array_Type representation defined, then
2100 -- replace this attribute with a direct reference to 'First of the
2101 -- appropriate index subtype (since otherwise the back end will try
2102 -- to give us the value of 'First for this implementation type).
2104 if Is_Constrained_Packed_Array
(Ptyp
) then
2106 Make_Attribute_Reference
(Loc
,
2107 Attribute_Name
=> Name_First
,
2108 Prefix
=> New_Reference_To
(Get_Index_Subtype
(N
), Loc
)));
2109 Analyze_And_Resolve
(N
, Typ
);
2111 elsif Is_Access_Type
(Ptyp
) then
2112 Apply_Access_Check
(N
);
2119 -- Compute this if component clause was present, otherwise we leave the
2120 -- computation to be completed in the back-end, since we don't know what
2121 -- layout will be chosen.
2123 when Attribute_First_Bit
=> First_Bit_Attr
: declare
2124 CE
: constant Entity_Id
:= Entity
(Selector_Name
(Pref
));
2127 -- In Ada 2005 (or later) if we have the standard nondefault
2128 -- bit order, then we return the original value as given in
2129 -- the component clause (RM 2005 13.5.2(3/2)).
2131 if Present
(Component_Clause
(CE
))
2132 and then Ada_Version
>= Ada_2005
2133 and then not Reverse_Bit_Order
(Scope
(CE
))
2136 Make_Integer_Literal
(Loc
,
2137 Intval
=> Expr_Value
(First_Bit
(Component_Clause
(CE
)))));
2138 Analyze_And_Resolve
(N
, Typ
);
2140 -- Otherwise (Ada 83/95 or Ada 2005 or later with reverse bit order),
2141 -- rewrite with normalized value if we know it statically.
2143 elsif Known_Static_Component_Bit_Offset
(CE
) then
2145 Make_Integer_Literal
(Loc
,
2146 Component_Bit_Offset
(CE
) mod System_Storage_Unit
));
2147 Analyze_And_Resolve
(N
, Typ
);
2149 -- Otherwise left to back end, just do universal integer checks
2152 Apply_Universal_Integer_Attribute_Checks
(N
);
2162 -- fixtype'Fixed_Value (integer-value)
2166 -- fixtype(integer-value)
2168 -- We do all the required analysis of the conversion here, because we do
2169 -- not want this to go through the fixed-point conversion circuits. Note
2170 -- that the back end always treats fixed-point as equivalent to the
2171 -- corresponding integer type anyway.
2173 when Attribute_Fixed_Value
=> Fixed_Value
:
2176 Make_Type_Conversion
(Loc
,
2177 Subtype_Mark
=> New_Occurrence_Of
(Entity
(Pref
), Loc
),
2178 Expression
=> Relocate_Node
(First
(Exprs
))));
2179 Set_Etype
(N
, Entity
(Pref
));
2182 -- Note: it might appear that a properly analyzed unchecked conversion
2183 -- would be just fine here, but that's not the case, since the full
2184 -- range checks performed by the following call are critical!
2186 Apply_Type_Conversion_Checks
(N
);
2193 -- Transforms 'Floor into a call to the floating-point attribute
2194 -- function Floor in Fat_xxx (where xxx is the root type)
2196 when Attribute_Floor
=>
2197 Expand_Fpt_Attribute_R
(N
);
2203 -- For the fixed-point type Typ:
2209 -- Result_Type (System.Fore (Universal_Real (Type'First)),
2210 -- Universal_Real (Type'Last))
2212 -- Note that we know that the type is a non-static subtype, or Fore
2213 -- would have itself been computed dynamically in Eval_Attribute.
2215 when Attribute_Fore
=> Fore
: begin
2218 Make_Function_Call
(Loc
,
2219 Name
=> New_Reference_To
(RTE
(RE_Fore
), Loc
),
2221 Parameter_Associations
=> New_List
(
2222 Convert_To
(Universal_Real
,
2223 Make_Attribute_Reference
(Loc
,
2224 Prefix
=> New_Reference_To
(Ptyp
, Loc
),
2225 Attribute_Name
=> Name_First
)),
2227 Convert_To
(Universal_Real
,
2228 Make_Attribute_Reference
(Loc
,
2229 Prefix
=> New_Reference_To
(Ptyp
, Loc
),
2230 Attribute_Name
=> Name_Last
))))));
2232 Analyze_And_Resolve
(N
, Typ
);
2239 -- Transforms 'Fraction into a call to the floating-point attribute
2240 -- function Fraction in Fat_xxx (where xxx is the root type)
2242 when Attribute_Fraction
=>
2243 Expand_Fpt_Attribute_R
(N
);
2249 when Attribute_From_Any
=> From_Any
: declare
2250 P_Type
: constant Entity_Id
:= Etype
(Pref
);
2251 Decls
: constant List_Id
:= New_List
;
2254 Build_From_Any_Call
(P_Type
,
2255 Relocate_Node
(First
(Exprs
)),
2257 Insert_Actions
(N
, Decls
);
2258 Analyze_And_Resolve
(N
, P_Type
);
2265 -- For an exception returns a reference to the exception data:
2266 -- Exception_Id!(Prefix'Reference)
2268 -- For a task it returns a reference to the _task_id component of
2269 -- corresponding record:
2271 -- taskV!(Prefix)._Task_Id, converted to the type Task_Id defined
2273 -- in Ada.Task_Identification
2275 when Attribute_Identity
=> Identity
: declare
2276 Id_Kind
: Entity_Id
;
2279 if Ptyp
= Standard_Exception_Type
then
2280 Id_Kind
:= RTE
(RE_Exception_Id
);
2282 if Present
(Renamed_Object
(Entity
(Pref
))) then
2283 Set_Entity
(Pref
, Renamed_Object
(Entity
(Pref
)));
2287 Unchecked_Convert_To
(Id_Kind
, Make_Reference
(Loc
, Pref
)));
2289 Id_Kind
:= RTE
(RO_AT_Task_Id
);
2291 -- If the prefix is a task interface, the Task_Id is obtained
2292 -- dynamically through a dispatching call, as for other task
2293 -- attributes applied to interfaces.
2295 if Ada_Version
>= Ada_2005
2296 and then Ekind
(Ptyp
) = E_Class_Wide_Type
2297 and then Is_Interface
(Ptyp
)
2298 and then Is_Task_Interface
(Ptyp
)
2301 Unchecked_Convert_To
(Id_Kind
,
2302 Make_Selected_Component
(Loc
,
2304 New_Copy_Tree
(Pref
),
2306 Make_Identifier
(Loc
, Name_uDisp_Get_Task_Id
))));
2310 Unchecked_Convert_To
(Id_Kind
, Concurrent_Ref
(Pref
)));
2314 Analyze_And_Resolve
(N
, Id_Kind
);
2321 -- Image attribute is handled in separate unit Exp_Imgv
2323 when Attribute_Image
=>
2324 Exp_Imgv
.Expand_Image_Attribute
(N
);
2330 -- X'Img is expanded to typ'Image (X), where typ is the type of X
2332 when Attribute_Img
=> Img
:
2335 Make_Attribute_Reference
(Loc
,
2336 Prefix
=> New_Reference_To
(Ptyp
, Loc
),
2337 Attribute_Name
=> Name_Image
,
2338 Expressions
=> New_List
(Relocate_Node
(Pref
))));
2340 Analyze_And_Resolve
(N
, Standard_String
);
2347 when Attribute_Input
=> Input
: declare
2348 P_Type
: constant Entity_Id
:= Entity
(Pref
);
2349 B_Type
: constant Entity_Id
:= Base_Type
(P_Type
);
2350 U_Type
: constant Entity_Id
:= Underlying_Type
(P_Type
);
2351 Strm
: constant Node_Id
:= First
(Exprs
);
2359 Cntrl
: Node_Id
:= Empty
;
2360 -- Value for controlling argument in call. Always Empty except in
2361 -- the dispatching (class-wide type) case, where it is a reference
2362 -- to the dummy object initialized to the right internal tag.
2364 procedure Freeze_Stream_Subprogram
(F
: Entity_Id
);
2365 -- The expansion of the attribute reference may generate a call to
2366 -- a user-defined stream subprogram that is frozen by the call. This
2367 -- can lead to access-before-elaboration problem if the reference
2368 -- appears in an object declaration and the subprogram body has not
2369 -- been seen. The freezing of the subprogram requires special code
2370 -- because it appears in an expanded context where expressions do
2371 -- not freeze their constituents.
2373 ------------------------------
2374 -- Freeze_Stream_Subprogram --
2375 ------------------------------
2377 procedure Freeze_Stream_Subprogram
(F
: Entity_Id
) is
2378 Decl
: constant Node_Id
:= Unit_Declaration_Node
(F
);
2382 -- If this is user-defined subprogram, the corresponding
2383 -- stream function appears as a renaming-as-body, and the
2384 -- user subprogram must be retrieved by tree traversal.
2387 and then Nkind
(Decl
) = N_Subprogram_Declaration
2388 and then Present
(Corresponding_Body
(Decl
))
2390 Bod
:= Corresponding_Body
(Decl
);
2392 if Nkind
(Unit_Declaration_Node
(Bod
)) =
2393 N_Subprogram_Renaming_Declaration
2395 Set_Is_Frozen
(Entity
(Name
(Unit_Declaration_Node
(Bod
))));
2398 end Freeze_Stream_Subprogram
;
2400 -- Start of processing for Input
2403 -- If no underlying type, we have an error that will be diagnosed
2404 -- elsewhere, so here we just completely ignore the expansion.
2410 -- If there is a TSS for Input, just call it
2412 Fname
:= Find_Stream_Subprogram
(P_Type
, TSS_Stream_Input
);
2414 if Present
(Fname
) then
2418 -- If there is a Stream_Convert pragma, use it, we rewrite
2420 -- sourcetyp'Input (stream)
2424 -- sourcetyp (streamread (strmtyp'Input (stream)));
2426 -- where streamread is the given Read function that converts an
2427 -- argument of type strmtyp to type sourcetyp or a type from which
2428 -- it is derived (extra conversion required for the derived case).
2430 Prag
:= Get_Stream_Convert_Pragma
(P_Type
);
2432 if Present
(Prag
) then
2433 Arg2
:= Next
(First
(Pragma_Argument_Associations
(Prag
)));
2434 Rfunc
:= Entity
(Expression
(Arg2
));
2438 Make_Function_Call
(Loc
,
2439 Name
=> New_Occurrence_Of
(Rfunc
, Loc
),
2440 Parameter_Associations
=> New_List
(
2441 Make_Attribute_Reference
(Loc
,
2444 (Etype
(First_Formal
(Rfunc
)), Loc
),
2445 Attribute_Name
=> Name_Input
,
2446 Expressions
=> Exprs
)))));
2448 Analyze_And_Resolve
(N
, B_Type
);
2453 elsif Is_Elementary_Type
(U_Type
) then
2455 -- A special case arises if we have a defined _Read routine,
2456 -- since in this case we are required to call this routine.
2458 if Present
(TSS
(Base_Type
(U_Type
), TSS_Stream_Read
)) then
2459 Build_Record_Or_Elementary_Input_Function
2460 (Loc
, U_Type
, Decl
, Fname
);
2461 Insert_Action
(N
, Decl
);
2463 -- For normal cases, we call the I_xxx routine directly
2466 Rewrite
(N
, Build_Elementary_Input_Call
(N
));
2467 Analyze_And_Resolve
(N
, P_Type
);
2473 elsif Is_Array_Type
(U_Type
) then
2474 Build_Array_Input_Function
(Loc
, U_Type
, Decl
, Fname
);
2475 Compile_Stream_Body_In_Scope
(N
, Decl
, U_Type
, Check
=> False);
2477 -- Dispatching case with class-wide type
2479 elsif Is_Class_Wide_Type
(P_Type
) then
2481 -- No need to do anything else compiling under restriction
2482 -- No_Dispatching_Calls. During the semantic analysis we
2483 -- already notified such violation.
2485 if Restriction_Active
(No_Dispatching_Calls
) then
2490 Rtyp
: constant Entity_Id
:= Root_Type
(P_Type
);
2496 -- Read the internal tag (RM 13.13.2(34)) and use it to
2497 -- initialize a dummy tag object:
2499 -- Dnn : Ada.Tags.Tag :=
2500 -- Descendant_Tag (String'Input (Strm), P_Type);
2502 -- This dummy object is used only to provide a controlling
2503 -- argument for the eventual _Input call. Descendant_Tag is
2504 -- called rather than Internal_Tag to ensure that we have a
2505 -- tag for a type that is descended from the prefix type and
2506 -- declared at the same accessibility level (the exception
2507 -- Tag_Error will be raised otherwise). The level check is
2508 -- required for Ada 2005 because tagged types can be
2509 -- extended in nested scopes (AI-344).
2512 Make_Function_Call
(Loc
,
2514 New_Occurrence_Of
(RTE
(RE_Descendant_Tag
), Loc
),
2515 Parameter_Associations
=> New_List
(
2516 Make_Attribute_Reference
(Loc
,
2517 Prefix
=> New_Occurrence_Of
(Standard_String
, Loc
),
2518 Attribute_Name
=> Name_Input
,
2519 Expressions
=> New_List
(
2520 Relocate_Node
(Duplicate_Subexpr
(Strm
)))),
2521 Make_Attribute_Reference
(Loc
,
2522 Prefix
=> New_Reference_To
(P_Type
, Loc
),
2523 Attribute_Name
=> Name_Tag
)));
2525 Dnn
:= Make_Temporary
(Loc
, 'D', Expr
);
2528 Make_Object_Declaration
(Loc
,
2529 Defining_Identifier
=> Dnn
,
2530 Object_Definition
=>
2531 New_Occurrence_Of
(RTE
(RE_Tag
), Loc
),
2532 Expression
=> Expr
);
2534 Insert_Action
(N
, Decl
);
2536 -- Now we need to get the entity for the call, and construct
2537 -- a function call node, where we preset a reference to Dnn
2538 -- as the controlling argument (doing an unchecked convert
2539 -- to the class-wide tagged type to make it look like a real
2542 Fname
:= Find_Prim_Op
(Rtyp
, TSS_Stream_Input
);
2544 Unchecked_Convert_To
(P_Type
,
2545 New_Occurrence_Of
(Dnn
, Loc
));
2546 Set_Etype
(Cntrl
, P_Type
);
2547 Set_Parent
(Cntrl
, N
);
2550 -- For tagged types, use the primitive Input function
2552 elsif Is_Tagged_Type
(U_Type
) then
2553 Fname
:= Find_Prim_Op
(U_Type
, TSS_Stream_Input
);
2555 -- All other record type cases, including protected records. The
2556 -- latter only arise for expander generated code for handling
2557 -- shared passive partition access.
2561 (Is_Record_Type
(U_Type
) or else Is_Protected_Type
(U_Type
));
2563 -- Ada 2005 (AI-216): Program_Error is raised executing default
2564 -- implementation of the Input attribute of an unchecked union
2565 -- type if the type lacks default discriminant values.
2567 if Is_Unchecked_Union
(Base_Type
(U_Type
))
2568 and then No
(Discriminant_Constraint
(U_Type
))
2571 Make_Raise_Program_Error
(Loc
,
2572 Reason
=> PE_Unchecked_Union_Restriction
));
2577 -- Build the type's Input function, passing the subtype rather
2578 -- than its base type, because checks are needed in the case of
2579 -- constrained discriminants (see Ada 2012 AI05-0192).
2581 Build_Record_Or_Elementary_Input_Function
2582 (Loc
, U_Type
, Decl
, Fname
);
2583 Insert_Action
(N
, Decl
);
2585 if Nkind
(Parent
(N
)) = N_Object_Declaration
2586 and then Is_Record_Type
(U_Type
)
2588 -- The stream function may contain calls to user-defined
2589 -- Read procedures for individual components.
2596 Comp
:= First_Component
(U_Type
);
2597 while Present
(Comp
) loop
2599 Find_Stream_Subprogram
2600 (Etype
(Comp
), TSS_Stream_Read
);
2602 if Present
(Func
) then
2603 Freeze_Stream_Subprogram
(Func
);
2606 Next_Component
(Comp
);
2613 -- If we fall through, Fname is the function to be called. The result
2614 -- is obtained by calling the appropriate function, then converting
2615 -- the result. The conversion does a subtype check.
2618 Make_Function_Call
(Loc
,
2619 Name
=> New_Occurrence_Of
(Fname
, Loc
),
2620 Parameter_Associations
=> New_List
(
2621 Relocate_Node
(Strm
)));
2623 Set_Controlling_Argument
(Call
, Cntrl
);
2624 Rewrite
(N
, Unchecked_Convert_To
(P_Type
, Call
));
2625 Analyze_And_Resolve
(N
, P_Type
);
2627 if Nkind
(Parent
(N
)) = N_Object_Declaration
then
2628 Freeze_Stream_Subprogram
(Fname
);
2638 -- inttype'Fixed_Value (fixed-value)
2642 -- inttype(integer-value))
2644 -- we do all the required analysis of the conversion here, because we do
2645 -- not want this to go through the fixed-point conversion circuits. Note
2646 -- that the back end always treats fixed-point as equivalent to the
2647 -- corresponding integer type anyway.
2649 when Attribute_Integer_Value
=> Integer_Value
:
2652 Make_Type_Conversion
(Loc
,
2653 Subtype_Mark
=> New_Occurrence_Of
(Entity
(Pref
), Loc
),
2654 Expression
=> Relocate_Node
(First
(Exprs
))));
2655 Set_Etype
(N
, Entity
(Pref
));
2658 -- Note: it might appear that a properly analyzed unchecked conversion
2659 -- would be just fine here, but that's not the case, since the full
2660 -- range checks performed by the following call are critical!
2662 Apply_Type_Conversion_Checks
(N
);
2669 when Attribute_Invalid_Value
=>
2670 Rewrite
(N
, Get_Simple_Init_Val
(Ptyp
, N
));
2676 when Attribute_Last
=>
2678 -- If the prefix type is a constrained packed array type which
2679 -- already has a Packed_Array_Type representation defined, then
2680 -- replace this attribute with a direct reference to 'Last of the
2681 -- appropriate index subtype (since otherwise the back end will try
2682 -- to give us the value of 'Last for this implementation type).
2684 if Is_Constrained_Packed_Array
(Ptyp
) then
2686 Make_Attribute_Reference
(Loc
,
2687 Attribute_Name
=> Name_Last
,
2688 Prefix
=> New_Reference_To
(Get_Index_Subtype
(N
), Loc
)));
2689 Analyze_And_Resolve
(N
, Typ
);
2691 elsif Is_Access_Type
(Ptyp
) then
2692 Apply_Access_Check
(N
);
2699 -- We compute this if a component clause was present, otherwise we leave
2700 -- the computation up to the back end, since we don't know what layout
2703 when Attribute_Last_Bit
=> Last_Bit_Attr
: declare
2704 CE
: constant Entity_Id
:= Entity
(Selector_Name
(Pref
));
2707 -- In Ada 2005 (or later) if we have the standard nondefault
2708 -- bit order, then we return the original value as given in
2709 -- the component clause (RM 2005 13.5.2(4/2)).
2711 if Present
(Component_Clause
(CE
))
2712 and then Ada_Version
>= Ada_2005
2713 and then not Reverse_Bit_Order
(Scope
(CE
))
2716 Make_Integer_Literal
(Loc
,
2717 Intval
=> Expr_Value
(Last_Bit
(Component_Clause
(CE
)))));
2718 Analyze_And_Resolve
(N
, Typ
);
2720 -- Otherwise (Ada 83/95 or Ada 2005 or later with reverse bit order),
2721 -- rewrite with normalized value if we know it statically.
2723 elsif Known_Static_Component_Bit_Offset
(CE
)
2724 and then Known_Static_Esize
(CE
)
2727 Make_Integer_Literal
(Loc
,
2728 Intval
=> (Component_Bit_Offset
(CE
) mod System_Storage_Unit
)
2730 Analyze_And_Resolve
(N
, Typ
);
2732 -- Otherwise leave to back end, just apply universal integer checks
2735 Apply_Universal_Integer_Attribute_Checks
(N
);
2743 -- Transforms 'Leading_Part into a call to the floating-point attribute
2744 -- function Leading_Part in Fat_xxx (where xxx is the root type)
2746 -- Note: strictly, we should generate special case code to deal with
2747 -- absurdly large positive arguments (greater than Integer'Last), which
2748 -- result in returning the first argument unchanged, but it hardly seems
2749 -- worth the effort. We raise constraint error for absurdly negative
2750 -- arguments which is fine.
2752 when Attribute_Leading_Part
=>
2753 Expand_Fpt_Attribute_RI
(N
);
2759 when Attribute_Length
=> declare
2764 -- Processing for packed array types
2766 if Is_Array_Type
(Ptyp
) and then Is_Packed
(Ptyp
) then
2767 Ityp
:= Get_Index_Subtype
(N
);
2769 -- If the index type, Ityp, is an enumeration type with holes,
2770 -- then we calculate X'Length explicitly using
2773 -- (0, Ityp'Pos (X'Last (N)) -
2774 -- Ityp'Pos (X'First (N)) + 1);
2776 -- Since the bounds in the template are the representation values
2777 -- and the back end would get the wrong value.
2779 if Is_Enumeration_Type
(Ityp
)
2780 and then Present
(Enum_Pos_To_Rep
(Base_Type
(Ityp
)))
2785 Xnum
:= Expr_Value
(First
(Expressions
(N
)));
2789 Make_Attribute_Reference
(Loc
,
2790 Prefix
=> New_Occurrence_Of
(Typ
, Loc
),
2791 Attribute_Name
=> Name_Max
,
2792 Expressions
=> New_List
2793 (Make_Integer_Literal
(Loc
, 0),
2797 Make_Op_Subtract
(Loc
,
2799 Make_Attribute_Reference
(Loc
,
2800 Prefix
=> New_Occurrence_Of
(Ityp
, Loc
),
2801 Attribute_Name
=> Name_Pos
,
2803 Expressions
=> New_List
(
2804 Make_Attribute_Reference
(Loc
,
2805 Prefix
=> Duplicate_Subexpr
(Pref
),
2806 Attribute_Name
=> Name_Last
,
2807 Expressions
=> New_List
(
2808 Make_Integer_Literal
(Loc
, Xnum
))))),
2811 Make_Attribute_Reference
(Loc
,
2812 Prefix
=> New_Occurrence_Of
(Ityp
, Loc
),
2813 Attribute_Name
=> Name_Pos
,
2815 Expressions
=> New_List
(
2816 Make_Attribute_Reference
(Loc
,
2818 Duplicate_Subexpr_No_Checks
(Pref
),
2819 Attribute_Name
=> Name_First
,
2820 Expressions
=> New_List
(
2821 Make_Integer_Literal
(Loc
, Xnum
)))))),
2823 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1)))));
2825 Analyze_And_Resolve
(N
, Typ
, Suppress
=> All_Checks
);
2828 -- If the prefix type is a constrained packed array type which
2829 -- already has a Packed_Array_Type representation defined, then
2830 -- replace this attribute with a direct reference to 'Range_Length
2831 -- of the appropriate index subtype (since otherwise the back end
2832 -- will try to give us the value of 'Length for this
2833 -- implementation type).
2835 elsif Is_Constrained
(Ptyp
) then
2837 Make_Attribute_Reference
(Loc
,
2838 Attribute_Name
=> Name_Range_Length
,
2839 Prefix
=> New_Reference_To
(Ityp
, Loc
)));
2840 Analyze_And_Resolve
(N
, Typ
);
2845 elsif Is_Access_Type
(Ptyp
) then
2846 Apply_Access_Check
(N
);
2848 -- If the designated type is a packed array type, then we convert
2849 -- the reference to:
2852 -- xtyp'Pos (Pref'Last (Expr)) -
2853 -- xtyp'Pos (Pref'First (Expr)));
2855 -- This is a bit complex, but it is the easiest thing to do that
2856 -- works in all cases including enum types with holes xtyp here
2857 -- is the appropriate index type.
2860 Dtyp
: constant Entity_Id
:= Designated_Type
(Ptyp
);
2864 if Is_Array_Type
(Dtyp
) and then Is_Packed
(Dtyp
) then
2865 Xtyp
:= Get_Index_Subtype
(N
);
2868 Make_Attribute_Reference
(Loc
,
2869 Prefix
=> New_Occurrence_Of
(Typ
, Loc
),
2870 Attribute_Name
=> Name_Max
,
2871 Expressions
=> New_List
(
2872 Make_Integer_Literal
(Loc
, 0),
2875 Make_Integer_Literal
(Loc
, 1),
2876 Make_Op_Subtract
(Loc
,
2878 Make_Attribute_Reference
(Loc
,
2879 Prefix
=> New_Occurrence_Of
(Xtyp
, Loc
),
2880 Attribute_Name
=> Name_Pos
,
2881 Expressions
=> New_List
(
2882 Make_Attribute_Reference
(Loc
,
2883 Prefix
=> Duplicate_Subexpr
(Pref
),
2884 Attribute_Name
=> Name_Last
,
2886 New_Copy_List
(Exprs
)))),
2889 Make_Attribute_Reference
(Loc
,
2890 Prefix
=> New_Occurrence_Of
(Xtyp
, Loc
),
2891 Attribute_Name
=> Name_Pos
,
2892 Expressions
=> New_List
(
2893 Make_Attribute_Reference
(Loc
,
2895 Duplicate_Subexpr_No_Checks
(Pref
),
2896 Attribute_Name
=> Name_First
,
2898 New_Copy_List
(Exprs
)))))))));
2900 Analyze_And_Resolve
(N
, Typ
);
2904 -- Otherwise leave it to the back end
2907 Apply_Universal_Integer_Attribute_Checks
(N
);
2915 -- Transforms 'Machine into a call to the floating-point attribute
2916 -- function Machine in Fat_xxx (where xxx is the root type)
2918 when Attribute_Machine
=>
2919 Expand_Fpt_Attribute_R
(N
);
2921 ----------------------
2922 -- Machine_Rounding --
2923 ----------------------
2925 -- Transforms 'Machine_Rounding into a call to the floating-point
2926 -- attribute function Machine_Rounding in Fat_xxx (where xxx is the root
2927 -- type). Expansion is avoided for cases the back end can handle
2930 when Attribute_Machine_Rounding
=>
2931 if not Is_Inline_Floating_Point_Attribute
(N
) then
2932 Expand_Fpt_Attribute_R
(N
);
2939 -- Machine_Size is equivalent to Object_Size, so transform it into
2940 -- Object_Size and that way the back end never sees Machine_Size.
2942 when Attribute_Machine_Size
=>
2944 Make_Attribute_Reference
(Loc
,
2945 Prefix
=> Prefix
(N
),
2946 Attribute_Name
=> Name_Object_Size
));
2948 Analyze_And_Resolve
(N
, Typ
);
2954 -- The only case that can get this far is the dynamic case of the old
2955 -- Ada 83 Mantissa attribute for the fixed-point case. For this case,
2962 -- ityp (System.Mantissa.Mantissa_Value
2963 -- (Integer'Integer_Value (typ'First),
2964 -- Integer'Integer_Value (typ'Last)));
2966 when Attribute_Mantissa
=> Mantissa
: begin
2969 Make_Function_Call
(Loc
,
2970 Name
=> New_Occurrence_Of
(RTE
(RE_Mantissa_Value
), Loc
),
2972 Parameter_Associations
=> New_List
(
2974 Make_Attribute_Reference
(Loc
,
2975 Prefix
=> New_Occurrence_Of
(Standard_Integer
, Loc
),
2976 Attribute_Name
=> Name_Integer_Value
,
2977 Expressions
=> New_List
(
2979 Make_Attribute_Reference
(Loc
,
2980 Prefix
=> New_Occurrence_Of
(Ptyp
, Loc
),
2981 Attribute_Name
=> Name_First
))),
2983 Make_Attribute_Reference
(Loc
,
2984 Prefix
=> New_Occurrence_Of
(Standard_Integer
, Loc
),
2985 Attribute_Name
=> Name_Integer_Value
,
2986 Expressions
=> New_List
(
2988 Make_Attribute_Reference
(Loc
,
2989 Prefix
=> New_Occurrence_Of
(Ptyp
, Loc
),
2990 Attribute_Name
=> Name_Last
)))))));
2992 Analyze_And_Resolve
(N
, Typ
);
2995 ----------------------------------
2996 -- Max_Size_In_Storage_Elements --
2997 ----------------------------------
2999 when Attribute_Max_Size_In_Storage_Elements
=>
3000 Apply_Universal_Integer_Attribute_Checks
(N
);
3002 -- Heap-allocated controlled objects contain two extra pointers which
3003 -- are not part of the actual type. Transform the attribute reference
3004 -- into a runtime expression to add the size of the hidden header.
3006 -- Do not perform this expansion on .NET/JVM targets because the
3007 -- two pointers are already present in the type.
3009 if VM_Target
= No_VM
3010 and then Nkind
(N
) = N_Attribute_Reference
3011 and then Needs_Finalization
(Ptyp
)
3012 and then not Header_Size_Added
(N
)
3014 Set_Header_Size_Added
(N
);
3017 -- P'Max_Size_In_Storage_Elements +
3018 -- Universal_Integer
3019 -- (Header_Size_With_Padding (Ptyp'Alignment))
3023 Left_Opnd
=> Relocate_Node
(N
),
3025 Convert_To
(Universal_Integer
,
3026 Make_Function_Call
(Loc
,
3029 (RTE
(RE_Header_Size_With_Padding
), Loc
),
3031 Parameter_Associations
=> New_List
(
3032 Make_Attribute_Reference
(Loc
,
3034 New_Reference_To
(Ptyp
, Loc
),
3035 Attribute_Name
=> Name_Alignment
))))));
3041 --------------------
3042 -- Mechanism_Code --
3043 --------------------
3045 when Attribute_Mechanism_Code
=>
3047 -- We must replace the prefix in the renamed case
3049 if Is_Entity_Name
(Pref
)
3050 and then Present
(Alias
(Entity
(Pref
)))
3052 Set_Renamed_Subprogram
(Pref
, Alias
(Entity
(Pref
)));
3059 when Attribute_Mod
=> Mod_Case
: declare
3060 Arg
: constant Node_Id
:= Relocate_Node
(First
(Exprs
));
3061 Hi
: constant Node_Id
:= Type_High_Bound
(Etype
(Arg
));
3062 Modv
: constant Uint
:= Modulus
(Btyp
);
3066 -- This is not so simple. The issue is what type to use for the
3067 -- computation of the modular value.
3069 -- The easy case is when the modulus value is within the bounds
3070 -- of the signed integer type of the argument. In this case we can
3071 -- just do the computation in that signed integer type, and then
3072 -- do an ordinary conversion to the target type.
3074 if Modv
<= Expr_Value
(Hi
) then
3079 Right_Opnd
=> Make_Integer_Literal
(Loc
, Modv
))));
3081 -- Here we know that the modulus is larger than type'Last of the
3082 -- integer type. There are two cases to consider:
3084 -- a) The integer value is non-negative. In this case, it is
3085 -- returned as the result (since it is less than the modulus).
3087 -- b) The integer value is negative. In this case, we know that the
3088 -- result is modulus + value, where the value might be as small as
3089 -- -modulus. The trouble is what type do we use to do the subtract.
3090 -- No type will do, since modulus can be as big as 2**64, and no
3091 -- integer type accommodates this value. Let's do bit of algebra
3094 -- = modulus - (-value)
3095 -- = (modulus - 1) - (-value - 1)
3097 -- Now modulus - 1 is certainly in range of the modular type.
3098 -- -value is in the range 1 .. modulus, so -value -1 is in the
3099 -- range 0 .. modulus-1 which is in range of the modular type.
3100 -- Furthermore, (-value - 1) can be expressed as -(value + 1)
3101 -- which we can compute using the integer base type.
3103 -- Once this is done we analyze the conditional expression without
3104 -- range checks, because we know everything is in range, and we
3105 -- want to prevent spurious warnings on either branch.
3109 Make_Conditional_Expression
(Loc
,
3110 Expressions
=> New_List
(
3112 Left_Opnd
=> Duplicate_Subexpr
(Arg
),
3113 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0)),
3116 Duplicate_Subexpr_No_Checks
(Arg
)),
3118 Make_Op_Subtract
(Loc
,
3120 Make_Integer_Literal
(Loc
,
3121 Intval
=> Modv
- 1),
3127 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Arg
),
3129 Make_Integer_Literal
(Loc
,
3130 Intval
=> 1))))))));
3134 Analyze_And_Resolve
(N
, Btyp
, Suppress
=> All_Checks
);
3141 -- Transforms 'Model into a call to the floating-point attribute
3142 -- function Model in Fat_xxx (where xxx is the root type)
3144 when Attribute_Model
=>
3145 Expand_Fpt_Attribute_R
(N
);
3151 -- The processing for Object_Size shares the processing for Size
3157 when Attribute_Old
=> Old
: declare
3158 Tnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T', Pref
);
3163 -- Find the nearest subprogram body, ignoring _Preconditions
3167 Subp
:= Parent
(Subp
);
3168 exit when Nkind
(Subp
) = N_Subprogram_Body
3169 and then Chars
(Defining_Entity
(Subp
)) /= Name_uPostconditions
;
3172 -- Insert the initialized object declaration at the start of the
3173 -- subprogram's declarations.
3176 Make_Object_Declaration
(Loc
,
3177 Defining_Identifier
=> Tnn
,
3178 Constant_Present
=> True,
3179 Object_Definition
=> New_Occurrence_Of
(Etype
(N
), Loc
),
3180 Expression
=> Pref
);
3182 -- Push the subprogram's scope, so that the object will be analyzed
3183 -- in that context (rather than the context of the Precondition
3184 -- subprogram) and will have its Scope set properly.
3186 if Present
(Corresponding_Spec
(Subp
)) then
3187 Push_Scope
(Corresponding_Spec
(Subp
));
3189 Push_Scope
(Defining_Entity
(Subp
));
3192 if Is_Empty_List
(Declarations
(Subp
)) then
3193 Set_Declarations
(Subp
, New_List
(Asn_Stm
));
3196 Insert_Action
(First
(Declarations
(Subp
)), Asn_Stm
);
3201 Rewrite
(N
, New_Occurrence_Of
(Tnn
, Loc
));
3204 ----------------------
3205 -- Overlaps_Storage --
3206 ----------------------
3208 when Attribute_Overlaps_Storage
=> Overlaps_Storage
: declare
3209 Loc
: constant Source_Ptr
:= Sloc
(N
);
3211 X
: constant Node_Id
:= Prefix
(N
);
3212 Y
: constant Node_Id
:= First
(Expressions
(N
));
3215 X_Addr
, Y_Addr
: Node_Id
;
3216 -- the expressions for their integer addresses
3218 X_Size
, Y_Size
: Node_Id
;
3219 -- the expressions for their sizes
3224 -- Attribute expands into:
3226 -- if X'Address < Y'address then
3227 -- (X'address + X'Size - 1) >= Y'address
3229 -- (Y'address + Y'size - 1) >= X'Address
3232 -- with the proper address operations. We convert addresses to
3233 -- integer addresses to use predefined arithmetic. The size is
3234 -- expressed in storage units.
3237 Unchecked_Convert_To
(RTE
(RE_Integer_Address
),
3238 Make_Attribute_Reference
(Loc
,
3239 Attribute_Name
=> Name_Address
,
3240 Prefix
=> New_Copy_Tree
(X
)));
3243 Unchecked_Convert_To
(RTE
(RE_Integer_Address
),
3244 Make_Attribute_Reference
(Loc
,
3245 Attribute_Name
=> Name_Address
,
3246 Prefix
=> New_Copy_Tree
(Y
)));
3249 Make_Op_Divide
(Loc
,
3251 Make_Attribute_Reference
(Loc
,
3252 Attribute_Name
=> Name_Size
,
3253 Prefix
=> New_Copy_Tree
(X
)),
3255 Make_Integer_Literal
(Loc
, System_Storage_Unit
));
3258 Make_Op_Divide
(Loc
,
3260 Make_Attribute_Reference
(Loc
,
3261 Attribute_Name
=> Name_Size
,
3262 Prefix
=> New_Copy_Tree
(Y
)),
3264 Make_Integer_Literal
(Loc
, System_Storage_Unit
));
3268 Left_Opnd
=> X_Addr
,
3269 Right_Opnd
=> Y_Addr
);
3272 Make_Conditional_Expression
(Loc
,
3279 Left_Opnd
=> X_Addr
,
3281 Make_Op_Subtract
(Loc
,
3282 Left_Opnd
=> X_Size
,
3283 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))),
3284 Right_Opnd
=> Y_Addr
),
3288 Left_Opnd
=> Y_Addr
,
3290 Make_Op_Subtract
(Loc
,
3291 Left_Opnd
=> Y_Size
,
3292 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))),
3293 Right_Opnd
=> X_Addr
))));
3295 Analyze_And_Resolve
(N
, Standard_Boolean
);
3296 end Overlaps_Storage
;
3302 when Attribute_Output
=> Output
: declare
3303 P_Type
: constant Entity_Id
:= Entity
(Pref
);
3304 U_Type
: constant Entity_Id
:= Underlying_Type
(P_Type
);
3312 -- If no underlying type, we have an error that will be diagnosed
3313 -- elsewhere, so here we just completely ignore the expansion.
3319 -- If TSS for Output is present, just call it
3321 Pname
:= Find_Stream_Subprogram
(P_Type
, TSS_Stream_Output
);
3323 if Present
(Pname
) then
3327 -- If there is a Stream_Convert pragma, use it, we rewrite
3329 -- sourcetyp'Output (stream, Item)
3333 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
3335 -- where strmwrite is the given Write function that converts an
3336 -- argument of type sourcetyp or a type acctyp, from which it is
3337 -- derived to type strmtyp. The conversion to acttyp is required
3338 -- for the derived case.
3340 Prag
:= Get_Stream_Convert_Pragma
(P_Type
);
3342 if Present
(Prag
) then
3344 Next
(Next
(First
(Pragma_Argument_Associations
(Prag
))));
3345 Wfunc
:= Entity
(Expression
(Arg3
));
3348 Make_Attribute_Reference
(Loc
,
3349 Prefix
=> New_Occurrence_Of
(Etype
(Wfunc
), Loc
),
3350 Attribute_Name
=> Name_Output
,
3351 Expressions
=> New_List
(
3352 Relocate_Node
(First
(Exprs
)),
3353 Make_Function_Call
(Loc
,
3354 Name
=> New_Occurrence_Of
(Wfunc
, Loc
),
3355 Parameter_Associations
=> New_List
(
3356 OK_Convert_To
(Etype
(First_Formal
(Wfunc
)),
3357 Relocate_Node
(Next
(First
(Exprs
)))))))));
3362 -- For elementary types, we call the W_xxx routine directly.
3363 -- Note that the effect of Write and Output is identical for
3364 -- the case of an elementary type, since there are no
3365 -- discriminants or bounds.
3367 elsif Is_Elementary_Type
(U_Type
) then
3369 -- A special case arises if we have a defined _Write routine,
3370 -- since in this case we are required to call this routine.
3372 if Present
(TSS
(Base_Type
(U_Type
), TSS_Stream_Write
)) then
3373 Build_Record_Or_Elementary_Output_Procedure
3374 (Loc
, U_Type
, Decl
, Pname
);
3375 Insert_Action
(N
, Decl
);
3377 -- For normal cases, we call the W_xxx routine directly
3380 Rewrite
(N
, Build_Elementary_Write_Call
(N
));
3387 elsif Is_Array_Type
(U_Type
) then
3388 Build_Array_Output_Procedure
(Loc
, U_Type
, Decl
, Pname
);
3389 Compile_Stream_Body_In_Scope
(N
, Decl
, U_Type
, Check
=> False);
3391 -- Class-wide case, first output external tag, then dispatch
3392 -- to the appropriate primitive Output function (RM 13.13.2(31)).
3394 elsif Is_Class_Wide_Type
(P_Type
) then
3396 -- No need to do anything else compiling under restriction
3397 -- No_Dispatching_Calls. During the semantic analysis we
3398 -- already notified such violation.
3400 if Restriction_Active
(No_Dispatching_Calls
) then
3405 Strm
: constant Node_Id
:= First
(Exprs
);
3406 Item
: constant Node_Id
:= Next
(Strm
);
3409 -- Ada 2005 (AI-344): Check that the accessibility level
3410 -- of the type of the output object is not deeper than
3411 -- that of the attribute's prefix type.
3413 -- if Get_Access_Level (Item'Tag)
3414 -- /= Get_Access_Level (P_Type'Tag)
3419 -- String'Output (Strm, External_Tag (Item'Tag));
3421 -- We cannot figure out a practical way to implement this
3422 -- accessibility check on virtual machines, so we omit it.
3424 if Ada_Version
>= Ada_2005
3425 and then Tagged_Type_Expansion
3428 Make_Implicit_If_Statement
(N
,
3432 Build_Get_Access_Level
(Loc
,
3433 Make_Attribute_Reference
(Loc
,
3436 Duplicate_Subexpr
(Item
,
3438 Attribute_Name
=> Name_Tag
)),
3441 Make_Integer_Literal
(Loc
,
3442 Type_Access_Level
(P_Type
))),
3445 New_List
(Make_Raise_Statement
(Loc
,
3447 RTE
(RE_Tag_Error
), Loc
)))));
3451 Make_Attribute_Reference
(Loc
,
3452 Prefix
=> New_Occurrence_Of
(Standard_String
, Loc
),
3453 Attribute_Name
=> Name_Output
,
3454 Expressions
=> New_List
(
3455 Relocate_Node
(Duplicate_Subexpr
(Strm
)),
3456 Make_Function_Call
(Loc
,
3458 New_Occurrence_Of
(RTE
(RE_External_Tag
), Loc
),
3459 Parameter_Associations
=> New_List
(
3460 Make_Attribute_Reference
(Loc
,
3463 (Duplicate_Subexpr
(Item
, Name_Req
=> True)),
3464 Attribute_Name
=> Name_Tag
))))));
3467 Pname
:= Find_Prim_Op
(U_Type
, TSS_Stream_Output
);
3469 -- Tagged type case, use the primitive Output function
3471 elsif Is_Tagged_Type
(U_Type
) then
3472 Pname
:= Find_Prim_Op
(U_Type
, TSS_Stream_Output
);
3474 -- All other record type cases, including protected records.
3475 -- The latter only arise for expander generated code for
3476 -- handling shared passive partition access.
3480 (Is_Record_Type
(U_Type
) or else Is_Protected_Type
(U_Type
));
3482 -- Ada 2005 (AI-216): Program_Error is raised when executing
3483 -- the default implementation of the Output attribute of an
3484 -- unchecked union type if the type lacks default discriminant
3487 if Is_Unchecked_Union
(Base_Type
(U_Type
))
3488 and then No
(Discriminant_Constraint
(U_Type
))
3491 Make_Raise_Program_Error
(Loc
,
3492 Reason
=> PE_Unchecked_Union_Restriction
));
3497 Build_Record_Or_Elementary_Output_Procedure
3498 (Loc
, Base_Type
(U_Type
), Decl
, Pname
);
3499 Insert_Action
(N
, Decl
);
3503 -- If we fall through, Pname is the name of the procedure to call
3505 Rewrite_Stream_Proc_Call
(Pname
);
3512 -- For enumeration types with a standard representation, Pos is
3513 -- handled by the back end.
3515 -- For enumeration types, with a non-standard representation we generate
3516 -- a call to the _Rep_To_Pos function created when the type was frozen.
3517 -- The call has the form
3519 -- _rep_to_pos (expr, flag)
3521 -- The parameter flag is True if range checks are enabled, causing
3522 -- Program_Error to be raised if the expression has an invalid
3523 -- representation, and False if range checks are suppressed.
3525 -- For integer types, Pos is equivalent to a simple integer
3526 -- conversion and we rewrite it as such
3528 when Attribute_Pos
=> Pos
:
3530 Etyp
: Entity_Id
:= Base_Type
(Entity
(Pref
));
3533 -- Deal with zero/non-zero boolean values
3535 if Is_Boolean_Type
(Etyp
) then
3536 Adjust_Condition
(First
(Exprs
));
3537 Etyp
:= Standard_Boolean
;
3538 Set_Prefix
(N
, New_Occurrence_Of
(Standard_Boolean
, Loc
));
3541 -- Case of enumeration type
3543 if Is_Enumeration_Type
(Etyp
) then
3545 -- Non-standard enumeration type (generate call)
3547 if Present
(Enum_Pos_To_Rep
(Etyp
)) then
3548 Append_To
(Exprs
, Rep_To_Pos_Flag
(Etyp
, Loc
));
3551 Make_Function_Call
(Loc
,
3553 New_Reference_To
(TSS
(Etyp
, TSS_Rep_To_Pos
), Loc
),
3554 Parameter_Associations
=> Exprs
)));
3556 Analyze_And_Resolve
(N
, Typ
);
3558 -- Standard enumeration type (do universal integer check)
3561 Apply_Universal_Integer_Attribute_Checks
(N
);
3564 -- Deal with integer types (replace by conversion)
3566 elsif Is_Integer_Type
(Etyp
) then
3567 Rewrite
(N
, Convert_To
(Typ
, First
(Exprs
)));
3568 Analyze_And_Resolve
(N
, Typ
);
3577 -- We compute this if a component clause was present, otherwise we leave
3578 -- the computation up to the back end, since we don't know what layout
3581 when Attribute_Position
=> Position_Attr
:
3583 CE
: constant Entity_Id
:= Entity
(Selector_Name
(Pref
));
3586 if Present
(Component_Clause
(CE
)) then
3588 -- In Ada 2005 (or later) if we have the standard nondefault
3589 -- bit order, then we return the original value as given in
3590 -- the component clause (RM 2005 13.5.2(2/2)).
3592 if Ada_Version
>= Ada_2005
3593 and then not Reverse_Bit_Order
(Scope
(CE
))
3596 Make_Integer_Literal
(Loc
,
3597 Intval
=> Expr_Value
(Position
(Component_Clause
(CE
)))));
3599 -- Otherwise (Ada 83 or 95, or reverse bit order specified in
3600 -- later Ada version), return the normalized value.
3604 Make_Integer_Literal
(Loc
,
3605 Intval
=> Component_Bit_Offset
(CE
) / System_Storage_Unit
));
3608 Analyze_And_Resolve
(N
, Typ
);
3610 -- If back end is doing things, just apply universal integer checks
3613 Apply_Universal_Integer_Attribute_Checks
(N
);
3621 -- 1. Deal with enumeration types with holes
3622 -- 2. For floating-point, generate call to attribute function
3623 -- 3. For other cases, deal with constraint checking
3625 when Attribute_Pred
=> Pred
:
3627 Etyp
: constant Entity_Id
:= Base_Type
(Ptyp
);
3631 -- For enumeration types with non-standard representations, we
3632 -- expand typ'Pred (x) into
3634 -- Pos_To_Rep (Rep_To_Pos (x) - 1)
3636 -- If the representation is contiguous, we compute instead
3637 -- Lit1 + Rep_to_Pos (x -1), to catch invalid representations.
3638 -- The conversion function Enum_Pos_To_Rep is defined on the
3639 -- base type, not the subtype, so we have to use the base type
3640 -- explicitly for this and other enumeration attributes.
3642 if Is_Enumeration_Type
(Ptyp
)
3643 and then Present
(Enum_Pos_To_Rep
(Etyp
))
3645 if Has_Contiguous_Rep
(Etyp
) then
3647 Unchecked_Convert_To
(Ptyp
,
3650 Make_Integer_Literal
(Loc
,
3651 Enumeration_Rep
(First_Literal
(Ptyp
))),
3653 Make_Function_Call
(Loc
,
3656 (TSS
(Etyp
, TSS_Rep_To_Pos
), Loc
),
3658 Parameter_Associations
=>
3660 Unchecked_Convert_To
(Ptyp
,
3661 Make_Op_Subtract
(Loc
,
3663 Unchecked_Convert_To
(Standard_Integer
,
3664 Relocate_Node
(First
(Exprs
))),
3666 Make_Integer_Literal
(Loc
, 1))),
3667 Rep_To_Pos_Flag
(Ptyp
, Loc
))))));
3670 -- Add Boolean parameter True, to request program errror if
3671 -- we have a bad representation on our hands. If checks are
3672 -- suppressed, then add False instead
3674 Append_To
(Exprs
, Rep_To_Pos_Flag
(Ptyp
, Loc
));
3676 Make_Indexed_Component
(Loc
,
3679 (Enum_Pos_To_Rep
(Etyp
), Loc
),
3680 Expressions
=> New_List
(
3681 Make_Op_Subtract
(Loc
,
3683 Make_Function_Call
(Loc
,
3686 (TSS
(Etyp
, TSS_Rep_To_Pos
), Loc
),
3687 Parameter_Associations
=> Exprs
),
3688 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1)))));
3691 Analyze_And_Resolve
(N
, Typ
);
3693 -- For floating-point, we transform 'Pred into a call to the Pred
3694 -- floating-point attribute function in Fat_xxx (xxx is root type)
3696 elsif Is_Floating_Point_Type
(Ptyp
) then
3697 Expand_Fpt_Attribute_R
(N
);
3698 Analyze_And_Resolve
(N
, Typ
);
3700 -- For modular types, nothing to do (no overflow, since wraps)
3702 elsif Is_Modular_Integer_Type
(Ptyp
) then
3705 -- For other types, if argument is marked as needing a range check or
3706 -- overflow checking is enabled, we must generate a check.
3708 elsif not Overflow_Checks_Suppressed
(Ptyp
)
3709 or else Do_Range_Check
(First
(Exprs
))
3711 Set_Do_Range_Check
(First
(Exprs
), False);
3712 Expand_Pred_Succ
(N
);
3720 -- Ada 2005 (AI-327): Dynamic ceiling priorities
3722 -- We rewrite X'Priority as the following run-time call:
3724 -- Get_Ceiling (X._Object)
3726 -- Note that although X'Priority is notionally an object, it is quite
3727 -- deliberately not defined as an aliased object in the RM. This means
3728 -- that it works fine to rewrite it as a call, without having to worry
3729 -- about complications that would other arise from X'Priority'Access,
3730 -- which is illegal, because of the lack of aliasing.
3732 when Attribute_Priority
=>
3735 Conctyp
: Entity_Id
;
3736 Object_Parm
: Node_Id
;
3738 RT_Subprg_Name
: Node_Id
;
3741 -- Look for the enclosing concurrent type
3743 Conctyp
:= Current_Scope
;
3744 while not Is_Concurrent_Type
(Conctyp
) loop
3745 Conctyp
:= Scope
(Conctyp
);
3748 pragma Assert
(Is_Protected_Type
(Conctyp
));
3750 -- Generate the actual of the call
3752 Subprg
:= Current_Scope
;
3753 while not Present
(Protected_Body_Subprogram
(Subprg
)) loop
3754 Subprg
:= Scope
(Subprg
);
3757 -- Use of 'Priority inside protected entries and barriers (in
3758 -- both cases the type of the first formal of their expanded
3759 -- subprogram is Address)
3761 if Etype
(First_Entity
(Protected_Body_Subprogram
(Subprg
)))
3765 New_Itype
: Entity_Id
;
3768 -- In the expansion of protected entries the type of the
3769 -- first formal of the Protected_Body_Subprogram is an
3770 -- Address. In order to reference the _object component
3773 -- type T is access p__ptTV;
3776 New_Itype
:= Create_Itype
(E_Access_Type
, N
);
3777 Set_Etype
(New_Itype
, New_Itype
);
3778 Set_Directly_Designated_Type
(New_Itype
,
3779 Corresponding_Record_Type
(Conctyp
));
3780 Freeze_Itype
(New_Itype
, N
);
3783 -- T!(O)._object'unchecked_access
3786 Make_Attribute_Reference
(Loc
,
3788 Make_Selected_Component
(Loc
,
3790 Unchecked_Convert_To
(New_Itype
,
3793 (Protected_Body_Subprogram
(Subprg
)),
3796 Make_Identifier
(Loc
, Name_uObject
)),
3797 Attribute_Name
=> Name_Unchecked_Access
);
3800 -- Use of 'Priority inside a protected subprogram
3804 Make_Attribute_Reference
(Loc
,
3806 Make_Selected_Component
(Loc
,
3807 Prefix
=> New_Reference_To
3809 (Protected_Body_Subprogram
(Subprg
)),
3811 Selector_Name
=> Make_Identifier
(Loc
, Name_uObject
)),
3812 Attribute_Name
=> Name_Unchecked_Access
);
3815 -- Select the appropriate run-time subprogram
3817 if Number_Entries
(Conctyp
) = 0 then
3819 New_Reference_To
(RTE
(RE_Get_Ceiling
), Loc
);
3822 New_Reference_To
(RTE
(RO_PE_Get_Ceiling
), Loc
);
3826 Make_Function_Call
(Loc
,
3827 Name
=> RT_Subprg_Name
,
3828 Parameter_Associations
=> New_List
(Object_Parm
));
3832 -- Avoid the generation of extra checks on the pointer to the
3833 -- protected object.
3835 Analyze_And_Resolve
(N
, Typ
, Suppress
=> Access_Check
);
3842 when Attribute_Range_Length
=> Range_Length
: begin
3844 -- The only special processing required is for the case where
3845 -- Range_Length is applied to an enumeration type with holes.
3846 -- In this case we transform
3852 -- X'Pos (X'Last) - X'Pos (X'First) + 1
3854 -- So that the result reflects the proper Pos values instead
3855 -- of the underlying representations.
3857 if Is_Enumeration_Type
(Ptyp
)
3858 and then Has_Non_Standard_Rep
(Ptyp
)
3863 Make_Op_Subtract
(Loc
,
3865 Make_Attribute_Reference
(Loc
,
3866 Attribute_Name
=> Name_Pos
,
3867 Prefix
=> New_Occurrence_Of
(Ptyp
, Loc
),
3868 Expressions
=> New_List
(
3869 Make_Attribute_Reference
(Loc
,
3870 Attribute_Name
=> Name_Last
,
3871 Prefix
=> New_Occurrence_Of
(Ptyp
, Loc
)))),
3874 Make_Attribute_Reference
(Loc
,
3875 Attribute_Name
=> Name_Pos
,
3876 Prefix
=> New_Occurrence_Of
(Ptyp
, Loc
),
3877 Expressions
=> New_List
(
3878 Make_Attribute_Reference
(Loc
,
3879 Attribute_Name
=> Name_First
,
3880 Prefix
=> New_Occurrence_Of
(Ptyp
, Loc
))))),
3882 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1)));
3884 Analyze_And_Resolve
(N
, Typ
);
3886 -- For all other cases, the attribute is handled by the back end, but
3887 -- we need to deal with the case of the range check on a universal
3891 Apply_Universal_Integer_Attribute_Checks
(N
);
3899 when Attribute_Read
=> Read
: declare
3900 P_Type
: constant Entity_Id
:= Entity
(Pref
);
3901 B_Type
: constant Entity_Id
:= Base_Type
(P_Type
);
3902 U_Type
: constant Entity_Id
:= Underlying_Type
(P_Type
);
3912 -- If no underlying type, we have an error that will be diagnosed
3913 -- elsewhere, so here we just completely ignore the expansion.
3919 -- The simple case, if there is a TSS for Read, just call it
3921 Pname
:= Find_Stream_Subprogram
(P_Type
, TSS_Stream_Read
);
3923 if Present
(Pname
) then
3927 -- If there is a Stream_Convert pragma, use it, we rewrite
3929 -- sourcetyp'Read (stream, Item)
3933 -- Item := sourcetyp (strmread (strmtyp'Input (Stream)));
3935 -- where strmread is the given Read function that converts an
3936 -- argument of type strmtyp to type sourcetyp or a type from which
3937 -- it is derived. The conversion to sourcetyp is required in the
3940 -- A special case arises if Item is a type conversion in which
3941 -- case, we have to expand to:
3943 -- Itemx := typex (strmread (strmtyp'Input (Stream)));
3945 -- where Itemx is the expression of the type conversion (i.e.
3946 -- the actual object), and typex is the type of Itemx.
3948 Prag
:= Get_Stream_Convert_Pragma
(P_Type
);
3950 if Present
(Prag
) then
3951 Arg2
:= Next
(First
(Pragma_Argument_Associations
(Prag
)));
3952 Rfunc
:= Entity
(Expression
(Arg2
));
3953 Lhs
:= Relocate_Node
(Next
(First
(Exprs
)));
3955 OK_Convert_To
(B_Type
,
3956 Make_Function_Call
(Loc
,
3957 Name
=> New_Occurrence_Of
(Rfunc
, Loc
),
3958 Parameter_Associations
=> New_List
(
3959 Make_Attribute_Reference
(Loc
,
3962 (Etype
(First_Formal
(Rfunc
)), Loc
),
3963 Attribute_Name
=> Name_Input
,
3964 Expressions
=> New_List
(
3965 Relocate_Node
(First
(Exprs
)))))));
3967 if Nkind
(Lhs
) = N_Type_Conversion
then
3968 Lhs
:= Expression
(Lhs
);
3969 Rhs
:= Convert_To
(Etype
(Lhs
), Rhs
);
3973 Make_Assignment_Statement
(Loc
,
3975 Expression
=> Rhs
));
3976 Set_Assignment_OK
(Lhs
);
3980 -- For elementary types, we call the I_xxx routine using the first
3981 -- parameter and then assign the result into the second parameter.
3982 -- We set Assignment_OK to deal with the conversion case.
3984 elsif Is_Elementary_Type
(U_Type
) then
3990 Lhs
:= Relocate_Node
(Next
(First
(Exprs
)));
3991 Rhs
:= Build_Elementary_Input_Call
(N
);
3993 if Nkind
(Lhs
) = N_Type_Conversion
then
3994 Lhs
:= Expression
(Lhs
);
3995 Rhs
:= Convert_To
(Etype
(Lhs
), Rhs
);
3998 Set_Assignment_OK
(Lhs
);
4001 Make_Assignment_Statement
(Loc
,
4003 Expression
=> Rhs
));
4011 elsif Is_Array_Type
(U_Type
) then
4012 Build_Array_Read_Procedure
(N
, U_Type
, Decl
, Pname
);
4013 Compile_Stream_Body_In_Scope
(N
, Decl
, U_Type
, Check
=> False);
4015 -- Tagged type case, use the primitive Read function. Note that
4016 -- this will dispatch in the class-wide case which is what we want
4018 elsif Is_Tagged_Type
(U_Type
) then
4019 Pname
:= Find_Prim_Op
(U_Type
, TSS_Stream_Read
);
4021 -- All other record type cases, including protected records. The
4022 -- latter only arise for expander generated code for handling
4023 -- shared passive partition access.
4027 (Is_Record_Type
(U_Type
) or else Is_Protected_Type
(U_Type
));
4029 -- Ada 2005 (AI-216): Program_Error is raised when executing
4030 -- the default implementation of the Read attribute of an
4031 -- Unchecked_Union type.
4033 if Is_Unchecked_Union
(Base_Type
(U_Type
)) then
4035 Make_Raise_Program_Error
(Loc
,
4036 Reason
=> PE_Unchecked_Union_Restriction
));
4039 if Has_Discriminants
(U_Type
)
4041 (Discriminant_Default_Value
(First_Discriminant
(U_Type
)))
4043 Build_Mutable_Record_Read_Procedure
4044 (Loc
, Full_Base
(U_Type
), Decl
, Pname
);
4046 Build_Record_Read_Procedure
4047 (Loc
, Full_Base
(U_Type
), Decl
, Pname
);
4050 -- Suppress checks, uninitialized or otherwise invalid
4051 -- data does not cause constraint errors to be raised for
4052 -- a complete record read.
4054 Insert_Action
(N
, Decl
, All_Checks
);
4058 Rewrite_Stream_Proc_Call
(Pname
);
4065 -- Ref is identical to To_Address, see To_Address for processing
4071 -- Transforms 'Remainder into a call to the floating-point attribute
4072 -- function Remainder in Fat_xxx (where xxx is the root type)
4074 when Attribute_Remainder
=>
4075 Expand_Fpt_Attribute_RR
(N
);
4081 -- Transform 'Result into reference to _Result formal. At the point
4082 -- where a legal 'Result attribute is expanded, we know that we are in
4083 -- the context of a _Postcondition function with a _Result parameter.
4085 when Attribute_Result
=>
4086 Rewrite
(N
, Make_Identifier
(Loc
, Chars
=> Name_uResult
));
4087 Analyze_And_Resolve
(N
, Typ
);
4093 -- The handling of the Round attribute is quite delicate. The processing
4094 -- in Sem_Attr introduced a conversion to universal real, reflecting the
4095 -- semantics of Round, but we do not want anything to do with universal
4096 -- real at runtime, since this corresponds to using floating-point
4099 -- What we have now is that the Etype of the Round attribute correctly
4100 -- indicates the final result type. The operand of the Round is the
4101 -- conversion to universal real, described above, and the operand of
4102 -- this conversion is the actual operand of Round, which may be the
4103 -- special case of a fixed point multiplication or division (Etype =
4106 -- The exapander will expand first the operand of the conversion, then
4107 -- the conversion, and finally the round attribute itself, since we
4108 -- always work inside out. But we cannot simply process naively in this
4109 -- order. In the semantic world where universal fixed and real really
4110 -- exist and have infinite precision, there is no problem, but in the
4111 -- implementation world, where universal real is a floating-point type,
4112 -- we would get the wrong result.
4114 -- So the approach is as follows. First, when expanding a multiply or
4115 -- divide whose type is universal fixed, we do nothing at all, instead
4116 -- deferring the operation till later.
4118 -- The actual processing is done in Expand_N_Type_Conversion which
4119 -- handles the special case of Round by looking at its parent to see if
4120 -- it is a Round attribute, and if it is, handling the conversion (or
4121 -- its fixed multiply/divide child) in an appropriate manner.
4123 -- This means that by the time we get to expanding the Round attribute
4124 -- itself, the Round is nothing more than a type conversion (and will
4125 -- often be a null type conversion), so we just replace it with the
4126 -- appropriate conversion operation.
4128 when Attribute_Round
=>
4130 Convert_To
(Etype
(N
), Relocate_Node
(First
(Exprs
))));
4131 Analyze_And_Resolve
(N
);
4137 -- Transforms 'Rounding into a call to the floating-point attribute
4138 -- function Rounding in Fat_xxx (where xxx is the root type)
4140 when Attribute_Rounding
=>
4141 Expand_Fpt_Attribute_R
(N
);
4147 when Attribute_Same_Storage
=> Same_Storage
: declare
4148 Loc
: constant Source_Ptr
:= Sloc
(N
);
4150 X
: constant Node_Id
:= Prefix
(N
);
4151 Y
: constant Node_Id
:= First
(Expressions
(N
));
4154 X_Addr
, Y_Addr
: Node_Id
;
4155 -- Rhe expressions for their addresses
4157 X_Size
, Y_Size
: Node_Id
;
4158 -- Rhe expressions for their sizes
4161 -- The attribute is expanded as:
4163 -- (X'address = Y'address)
4164 -- and then (X'Size = Y'Size)
4166 -- If both arguments have the same Etype the second conjunct can be
4170 Make_Attribute_Reference
(Loc
,
4171 Attribute_Name
=> Name_Address
,
4172 Prefix
=> New_Copy_Tree
(X
));
4175 Make_Attribute_Reference
(Loc
,
4176 Attribute_Name
=> Name_Address
,
4177 Prefix
=> New_Copy_Tree
(Y
));
4180 Make_Attribute_Reference
(Loc
,
4181 Attribute_Name
=> Name_Size
,
4182 Prefix
=> New_Copy_Tree
(X
));
4185 Make_Attribute_Reference
(Loc
,
4186 Attribute_Name
=> Name_Size
,
4187 Prefix
=> New_Copy_Tree
(Y
));
4189 if Etype
(X
) = Etype
(Y
) then
4192 Left_Opnd
=> X_Addr
,
4193 Right_Opnd
=> Y_Addr
)));
4199 Left_Opnd
=> X_Addr
,
4200 Right_Opnd
=> Y_Addr
),
4203 Left_Opnd
=> X_Size
,
4204 Right_Opnd
=> Y_Size
)));
4207 Analyze_And_Resolve
(N
, Standard_Boolean
);
4214 -- Transforms 'Scaling into a call to the floating-point attribute
4215 -- function Scaling in Fat_xxx (where xxx is the root type)
4217 when Attribute_Scaling
=>
4218 Expand_Fpt_Attribute_RI
(N
);
4224 when Attribute_Size |
4225 Attribute_Object_Size |
4226 Attribute_Value_Size |
4227 Attribute_VADS_Size
=> Size
:
4234 -- Processing for VADS_Size case. Note that this processing removes
4235 -- all traces of VADS_Size from the tree, and completes all required
4236 -- processing for VADS_Size by translating the attribute reference
4237 -- to an appropriate Size or Object_Size reference.
4239 if Id
= Attribute_VADS_Size
4240 or else (Use_VADS_Size
and then Id
= Attribute_Size
)
4242 -- If the size is specified, then we simply use the specified
4243 -- size. This applies to both types and objects. The size of an
4244 -- object can be specified in the following ways:
4246 -- An explicit size object is given for an object
4247 -- A component size is specified for an indexed component
4248 -- A component clause is specified for a selected component
4249 -- The object is a component of a packed composite object
4251 -- If the size is specified, then VADS_Size of an object
4253 if (Is_Entity_Name
(Pref
)
4254 and then Present
(Size_Clause
(Entity
(Pref
))))
4256 (Nkind
(Pref
) = N_Component_Clause
4257 and then (Present
(Component_Clause
4258 (Entity
(Selector_Name
(Pref
))))
4259 or else Is_Packed
(Etype
(Prefix
(Pref
)))))
4261 (Nkind
(Pref
) = N_Indexed_Component
4262 and then (Component_Size
(Etype
(Prefix
(Pref
))) /= 0
4263 or else Is_Packed
(Etype
(Prefix
(Pref
)))))
4265 Set_Attribute_Name
(N
, Name_Size
);
4267 -- Otherwise if we have an object rather than a type, then the
4268 -- VADS_Size attribute applies to the type of the object, rather
4269 -- than the object itself. This is one of the respects in which
4270 -- VADS_Size differs from Size.
4273 if (not Is_Entity_Name
(Pref
)
4274 or else not Is_Type
(Entity
(Pref
)))
4275 and then (Is_Scalar_Type
(Ptyp
) or else Is_Constrained
(Ptyp
))
4277 Rewrite
(Pref
, New_Occurrence_Of
(Ptyp
, Loc
));
4280 -- For a scalar type for which no size was explicitly given,
4281 -- VADS_Size means Object_Size. This is the other respect in
4282 -- which VADS_Size differs from Size.
4284 if Is_Scalar_Type
(Ptyp
) and then No
(Size_Clause
(Ptyp
)) then
4285 Set_Attribute_Name
(N
, Name_Object_Size
);
4287 -- In all other cases, Size and VADS_Size are the sane
4290 Set_Attribute_Name
(N
, Name_Size
);
4295 -- For class-wide types, X'Class'Size is transformed into a direct
4296 -- reference to the Size of the class type, so that the back end does
4297 -- not have to deal with the X'Class'Size reference.
4299 if Is_Entity_Name
(Pref
)
4300 and then Is_Class_Wide_Type
(Entity
(Pref
))
4302 Rewrite
(Prefix
(N
), New_Occurrence_Of
(Entity
(Pref
), Loc
));
4305 -- For X'Size applied to an object of a class-wide type, transform
4306 -- X'Size into a call to the primitive operation _Size applied to X.
4308 elsif Is_Class_Wide_Type
(Ptyp
)
4309 or else (Id
= Attribute_Size
4310 and then Is_Tagged_Type
(Ptyp
)
4311 and then Has_Unknown_Discriminants
(Ptyp
))
4313 -- No need to do anything else compiling under restriction
4314 -- No_Dispatching_Calls. During the semantic analysis we
4315 -- already notified such violation.
4317 if Restriction_Active
(No_Dispatching_Calls
) then
4322 Make_Function_Call
(Loc
,
4323 Name
=> New_Reference_To
4324 (Find_Prim_Op
(Ptyp
, Name_uSize
), Loc
),
4325 Parameter_Associations
=> New_List
(Pref
));
4327 if Typ
/= Standard_Long_Long_Integer
then
4329 -- The context is a specific integer type with which the
4330 -- original attribute was compatible. The function has a
4331 -- specific type as well, so to preserve the compatibility
4332 -- we must convert explicitly.
4334 New_Node
:= Convert_To
(Typ
, New_Node
);
4337 Rewrite
(N
, New_Node
);
4338 Analyze_And_Resolve
(N
, Typ
);
4341 -- Case of known RM_Size of a type
4343 elsif (Id
= Attribute_Size
or else Id
= Attribute_Value_Size
)
4344 and then Is_Entity_Name
(Pref
)
4345 and then Is_Type
(Entity
(Pref
))
4346 and then Known_Static_RM_Size
(Entity
(Pref
))
4348 Siz
:= RM_Size
(Entity
(Pref
));
4350 -- Case of known Esize of a type
4352 elsif Id
= Attribute_Object_Size
4353 and then Is_Entity_Name
(Pref
)
4354 and then Is_Type
(Entity
(Pref
))
4355 and then Known_Static_Esize
(Entity
(Pref
))
4357 Siz
:= Esize
(Entity
(Pref
));
4359 -- Case of known size of object
4361 elsif Id
= Attribute_Size
4362 and then Is_Entity_Name
(Pref
)
4363 and then Is_Object
(Entity
(Pref
))
4364 and then Known_Esize
(Entity
(Pref
))
4365 and then Known_Static_Esize
(Entity
(Pref
))
4367 Siz
:= Esize
(Entity
(Pref
));
4369 -- For an array component, we can do Size in the front end
4370 -- if the component_size of the array is set.
4372 elsif Nkind
(Pref
) = N_Indexed_Component
then
4373 Siz
:= Component_Size
(Etype
(Prefix
(Pref
)));
4375 -- For a record component, we can do Size in the front end if there
4376 -- is a component clause, or if the record is packed and the
4377 -- component's size is known at compile time.
4379 elsif Nkind
(Pref
) = N_Selected_Component
then
4381 Rec
: constant Entity_Id
:= Etype
(Prefix
(Pref
));
4382 Comp
: constant Entity_Id
:= Entity
(Selector_Name
(Pref
));
4385 if Present
(Component_Clause
(Comp
)) then
4386 Siz
:= Esize
(Comp
);
4388 elsif Is_Packed
(Rec
) then
4389 Siz
:= RM_Size
(Ptyp
);
4392 Apply_Universal_Integer_Attribute_Checks
(N
);
4397 -- All other cases are handled by the back end
4400 Apply_Universal_Integer_Attribute_Checks
(N
);
4402 -- If Size is applied to a formal parameter that is of a packed
4403 -- array subtype, then apply Size to the actual subtype.
4405 if Is_Entity_Name
(Pref
)
4406 and then Is_Formal
(Entity
(Pref
))
4407 and then Is_Array_Type
(Ptyp
)
4408 and then Is_Packed
(Ptyp
)
4411 Make_Attribute_Reference
(Loc
,
4413 New_Occurrence_Of
(Get_Actual_Subtype
(Pref
), Loc
),
4414 Attribute_Name
=> Name_Size
));
4415 Analyze_And_Resolve
(N
, Typ
);
4418 -- If Size applies to a dereference of an access to unconstrained
4419 -- packed array, the back end needs to see its unconstrained
4420 -- nominal type, but also a hint to the actual constrained type.
4422 if Nkind
(Pref
) = N_Explicit_Dereference
4423 and then Is_Array_Type
(Ptyp
)
4424 and then not Is_Constrained
(Ptyp
)
4425 and then Is_Packed
(Ptyp
)
4427 Set_Actual_Designated_Subtype
(Pref
,
4428 Get_Actual_Subtype
(Pref
));
4434 -- Common processing for record and array component case
4436 if Siz
/= No_Uint
and then Siz
/= 0 then
4438 CS
: constant Boolean := Comes_From_Source
(N
);
4441 Rewrite
(N
, Make_Integer_Literal
(Loc
, Siz
));
4443 -- This integer literal is not a static expression. We do not
4444 -- call Analyze_And_Resolve here, because this would activate
4445 -- the circuit for deciding that a static value was out of
4446 -- range, and we don't want that.
4448 -- So just manually set the type, mark the expression as non-
4449 -- static, and then ensure that the result is checked properly
4450 -- if the attribute comes from source (if it was internally
4451 -- generated, we never need a constraint check).
4454 Set_Is_Static_Expression
(N
, False);
4457 Apply_Constraint_Check
(N
, Typ
);
4467 when Attribute_Storage_Pool
=>
4469 Make_Type_Conversion
(Loc
,
4470 Subtype_Mark
=> New_Reference_To
(Etype
(N
), Loc
),
4471 Expression
=> New_Reference_To
(Entity
(N
), Loc
)));
4472 Analyze_And_Resolve
(N
, Typ
);
4478 when Attribute_Storage_Size
=> Storage_Size
: begin
4480 -- Access type case, always go to the root type
4482 -- The case of access types results in a value of zero for the case
4483 -- where no storage size attribute clause has been given. If a
4484 -- storage size has been given, then the attribute is converted
4485 -- to a reference to the variable used to hold this value.
4487 if Is_Access_Type
(Ptyp
) then
4488 if Present
(Storage_Size_Variable
(Root_Type
(Ptyp
))) then
4490 Make_Attribute_Reference
(Loc
,
4491 Prefix
=> New_Reference_To
(Typ
, Loc
),
4492 Attribute_Name
=> Name_Max
,
4493 Expressions
=> New_List
(
4494 Make_Integer_Literal
(Loc
, 0),
4497 (Storage_Size_Variable
(Root_Type
(Ptyp
)), Loc
)))));
4499 elsif Present
(Associated_Storage_Pool
(Root_Type
(Ptyp
))) then
4502 Make_Function_Call
(Loc
,
4506 (Etype
(Associated_Storage_Pool
(Root_Type
(Ptyp
))),
4507 Attribute_Name
(N
)),
4510 Parameter_Associations
=> New_List
(
4512 (Associated_Storage_Pool
(Root_Type
(Ptyp
)), Loc
)))));
4515 Rewrite
(N
, Make_Integer_Literal
(Loc
, 0));
4518 Analyze_And_Resolve
(N
, Typ
);
4520 -- For tasks, we retrieve the size directly from the TCB. The
4521 -- size may depend on a discriminant of the type, and therefore
4522 -- can be a per-object expression, so type-level information is
4523 -- not sufficient in general. There are four cases to consider:
4525 -- a) If the attribute appears within a task body, the designated
4526 -- TCB is obtained by a call to Self.
4528 -- b) If the prefix of the attribute is the name of a task object,
4529 -- the designated TCB is the one stored in the corresponding record.
4531 -- c) If the prefix is a task type, the size is obtained from the
4532 -- size variable created for each task type
4534 -- d) If no storage_size was specified for the type , there is no
4535 -- size variable, and the value is a system-specific default.
4538 if In_Open_Scopes
(Ptyp
) then
4540 -- Storage_Size (Self)
4544 Make_Function_Call
(Loc
,
4546 New_Occurrence_Of
(RTE
(RE_Storage_Size
), Loc
),
4547 Parameter_Associations
=>
4549 Make_Function_Call
(Loc
,
4551 New_Reference_To
(RTE
(RE_Self
), Loc
))))));
4553 elsif not Is_Entity_Name
(Pref
)
4554 or else not Is_Type
(Entity
(Pref
))
4556 -- Storage_Size (Rec (Obj).Size)
4560 Make_Function_Call
(Loc
,
4562 New_Occurrence_Of
(RTE
(RE_Storage_Size
), Loc
),
4563 Parameter_Associations
=>
4565 Make_Selected_Component
(Loc
,
4567 Unchecked_Convert_To
(
4568 Corresponding_Record_Type
(Ptyp
),
4569 New_Copy_Tree
(Pref
)),
4571 Make_Identifier
(Loc
, Name_uTask_Id
))))));
4573 elsif Present
(Storage_Size_Variable
(Ptyp
)) then
4575 -- Static storage size pragma given for type: retrieve value
4576 -- from its allocated storage variable.
4580 Make_Function_Call
(Loc
,
4581 Name
=> New_Occurrence_Of
(
4582 RTE
(RE_Adjust_Storage_Size
), Loc
),
4583 Parameter_Associations
=>
4586 Storage_Size_Variable
(Ptyp
), Loc
)))));
4588 -- Get system default
4592 Make_Function_Call
(Loc
,
4595 RTE
(RE_Default_Stack_Size
), Loc
))));
4598 Analyze_And_Resolve
(N
, Typ
);
4606 when Attribute_Stream_Size
=>
4608 Make_Integer_Literal
(Loc
, Intval
=> Get_Stream_Size
(Ptyp
)));
4609 Analyze_And_Resolve
(N
, Typ
);
4615 -- 1. Deal with enumeration types with holes
4616 -- 2. For floating-point, generate call to attribute function
4617 -- 3. For other cases, deal with constraint checking
4619 when Attribute_Succ
=> Succ
: declare
4620 Etyp
: constant Entity_Id
:= Base_Type
(Ptyp
);
4624 -- For enumeration types with non-standard representations, we
4625 -- expand typ'Succ (x) into
4627 -- Pos_To_Rep (Rep_To_Pos (x) + 1)
4629 -- If the representation is contiguous, we compute instead
4630 -- Lit1 + Rep_to_Pos (x+1), to catch invalid representations.
4632 if Is_Enumeration_Type
(Ptyp
)
4633 and then Present
(Enum_Pos_To_Rep
(Etyp
))
4635 if Has_Contiguous_Rep
(Etyp
) then
4637 Unchecked_Convert_To
(Ptyp
,
4640 Make_Integer_Literal
(Loc
,
4641 Enumeration_Rep
(First_Literal
(Ptyp
))),
4643 Make_Function_Call
(Loc
,
4646 (TSS
(Etyp
, TSS_Rep_To_Pos
), Loc
),
4648 Parameter_Associations
=>
4650 Unchecked_Convert_To
(Ptyp
,
4653 Unchecked_Convert_To
(Standard_Integer
,
4654 Relocate_Node
(First
(Exprs
))),
4656 Make_Integer_Literal
(Loc
, 1))),
4657 Rep_To_Pos_Flag
(Ptyp
, Loc
))))));
4659 -- Add Boolean parameter True, to request program errror if
4660 -- we have a bad representation on our hands. Add False if
4661 -- checks are suppressed.
4663 Append_To
(Exprs
, Rep_To_Pos_Flag
(Ptyp
, Loc
));
4665 Make_Indexed_Component
(Loc
,
4668 (Enum_Pos_To_Rep
(Etyp
), Loc
),
4669 Expressions
=> New_List
(
4672 Make_Function_Call
(Loc
,
4675 (TSS
(Etyp
, TSS_Rep_To_Pos
), Loc
),
4676 Parameter_Associations
=> Exprs
),
4677 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1)))));
4680 Analyze_And_Resolve
(N
, Typ
);
4682 -- For floating-point, we transform 'Succ into a call to the Succ
4683 -- floating-point attribute function in Fat_xxx (xxx is root type)
4685 elsif Is_Floating_Point_Type
(Ptyp
) then
4686 Expand_Fpt_Attribute_R
(N
);
4687 Analyze_And_Resolve
(N
, Typ
);
4689 -- For modular types, nothing to do (no overflow, since wraps)
4691 elsif Is_Modular_Integer_Type
(Ptyp
) then
4694 -- For other types, if argument is marked as needing a range check or
4695 -- overflow checking is enabled, we must generate a check.
4697 elsif not Overflow_Checks_Suppressed
(Ptyp
)
4698 or else Do_Range_Check
(First
(Exprs
))
4700 Set_Do_Range_Check
(First
(Exprs
), False);
4701 Expand_Pred_Succ
(N
);
4709 -- Transforms X'Tag into a direct reference to the tag of X
4711 when Attribute_Tag
=> Tag
: declare
4713 Prefix_Is_Type
: Boolean;
4716 if Is_Entity_Name
(Pref
) and then Is_Type
(Entity
(Pref
)) then
4717 Ttyp
:= Entity
(Pref
);
4718 Prefix_Is_Type
:= True;
4721 Prefix_Is_Type
:= False;
4724 if Is_Class_Wide_Type
(Ttyp
) then
4725 Ttyp
:= Root_Type
(Ttyp
);
4728 Ttyp
:= Underlying_Type
(Ttyp
);
4730 -- Ada 2005: The type may be a synchronized tagged type, in which
4731 -- case the tag information is stored in the corresponding record.
4733 if Is_Concurrent_Type
(Ttyp
) then
4734 Ttyp
:= Corresponding_Record_Type
(Ttyp
);
4737 if Prefix_Is_Type
then
4739 -- For VMs we leave the type attribute unexpanded because
4740 -- there's not a dispatching table to reference.
4742 if Tagged_Type_Expansion
then
4744 Unchecked_Convert_To
(RTE
(RE_Tag
),
4746 (Node
(First_Elmt
(Access_Disp_Table
(Ttyp
))), Loc
)));
4747 Analyze_And_Resolve
(N
, RTE
(RE_Tag
));
4750 -- Ada 2005 (AI-251): The use of 'Tag in the sources always
4751 -- references the primary tag of the actual object. If 'Tag is
4752 -- applied to class-wide interface objects we generate code that
4753 -- displaces "this" to reference the base of the object.
4755 elsif Comes_From_Source
(N
)
4756 and then Is_Class_Wide_Type
(Etype
(Prefix
(N
)))
4757 and then Is_Interface
(Etype
(Prefix
(N
)))
4760 -- (To_Tag_Ptr (Prefix'Address)).all
4762 -- Note that Prefix'Address is recursively expanded into a call
4763 -- to Base_Address (Obj.Tag)
4765 -- Not needed for VM targets, since all handled by the VM
4767 if Tagged_Type_Expansion
then
4769 Make_Explicit_Dereference
(Loc
,
4770 Unchecked_Convert_To
(RTE
(RE_Tag_Ptr
),
4771 Make_Attribute_Reference
(Loc
,
4772 Prefix
=> Relocate_Node
(Pref
),
4773 Attribute_Name
=> Name_Address
))));
4774 Analyze_And_Resolve
(N
, RTE
(RE_Tag
));
4779 Make_Selected_Component
(Loc
,
4780 Prefix
=> Relocate_Node
(Pref
),
4782 New_Reference_To
(First_Tag_Component
(Ttyp
), Loc
)));
4783 Analyze_And_Resolve
(N
, RTE
(RE_Tag
));
4791 -- Transforms 'Terminated attribute into a call to Terminated function
4793 when Attribute_Terminated
=> Terminated
:
4795 -- The prefix of Terminated is of a task interface class-wide type.
4797 -- terminated (Task_Id (Pref._disp_get_task_id));
4799 if Ada_Version
>= Ada_2005
4800 and then Ekind
(Ptyp
) = E_Class_Wide_Type
4801 and then Is_Interface
(Ptyp
)
4802 and then Is_Task_Interface
(Ptyp
)
4805 Make_Function_Call
(Loc
,
4807 New_Reference_To
(RTE
(RE_Terminated
), Loc
),
4808 Parameter_Associations
=> New_List
(
4809 Make_Unchecked_Type_Conversion
(Loc
,
4811 New_Reference_To
(RTE
(RO_ST_Task_Id
), Loc
),
4813 Make_Selected_Component
(Loc
,
4815 New_Copy_Tree
(Pref
),
4817 Make_Identifier
(Loc
, Name_uDisp_Get_Task_Id
))))));
4819 elsif Restricted_Profile
then
4821 Build_Call_With_Task
(Pref
, RTE
(RE_Restricted_Terminated
)));
4825 Build_Call_With_Task
(Pref
, RTE
(RE_Terminated
)));
4828 Analyze_And_Resolve
(N
, Standard_Boolean
);
4835 -- Transforms System'To_Address (X) and System.Address'Ref (X) into
4836 -- unchecked conversion from (integral) type of X to type address.
4838 when Attribute_To_Address | Attribute_Ref
=>
4840 Unchecked_Convert_To
(RTE
(RE_Address
),
4841 Relocate_Node
(First
(Exprs
))));
4842 Analyze_And_Resolve
(N
, RTE
(RE_Address
));
4848 when Attribute_To_Any
=> To_Any
: declare
4849 P_Type
: constant Entity_Id
:= Etype
(Pref
);
4850 Decls
: constant List_Id
:= New_List
;
4854 (Convert_To
(P_Type
,
4855 Relocate_Node
(First
(Exprs
))), Decls
));
4856 Insert_Actions
(N
, Decls
);
4857 Analyze_And_Resolve
(N
, RTE
(RE_Any
));
4864 -- Transforms 'Truncation into a call to the floating-point attribute
4865 -- function Truncation in Fat_xxx (where xxx is the root type).
4866 -- Expansion is avoided for cases the back end can handle directly.
4868 when Attribute_Truncation
=>
4869 if not Is_Inline_Floating_Point_Attribute
(N
) then
4870 Expand_Fpt_Attribute_R
(N
);
4877 when Attribute_TypeCode
=> TypeCode
: declare
4878 P_Type
: constant Entity_Id
:= Etype
(Pref
);
4879 Decls
: constant List_Id
:= New_List
;
4881 Rewrite
(N
, Build_TypeCode_Call
(Loc
, P_Type
, Decls
));
4882 Insert_Actions
(N
, Decls
);
4883 Analyze_And_Resolve
(N
, RTE
(RE_TypeCode
));
4886 -----------------------
4887 -- Unbiased_Rounding --
4888 -----------------------
4890 -- Transforms 'Unbiased_Rounding into a call to the floating-point
4891 -- attribute function Unbiased_Rounding in Fat_xxx (where xxx is the
4892 -- root type). Expansion is avoided for cases the back end can handle
4895 when Attribute_Unbiased_Rounding
=>
4896 if not Is_Inline_Floating_Point_Attribute
(N
) then
4897 Expand_Fpt_Attribute_R
(N
);
4904 when Attribute_UET_Address
=> UET_Address
: declare
4905 Ent
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
4909 Make_Object_Declaration
(Loc
,
4910 Defining_Identifier
=> Ent
,
4911 Aliased_Present
=> True,
4912 Object_Definition
=>
4913 New_Occurrence_Of
(RTE
(RE_Address
), Loc
)));
4915 -- Construct name __gnat_xxx__SDP, where xxx is the unit name
4916 -- in normal external form.
4918 Get_External_Unit_Name_String
(Get_Unit_Name
(Pref
));
4919 Name_Buffer
(1 + 7 .. Name_Len
+ 7) := Name_Buffer
(1 .. Name_Len
);
4920 Name_Len
:= Name_Len
+ 7;
4921 Name_Buffer
(1 .. 7) := "__gnat_";
4922 Name_Buffer
(Name_Len
+ 1 .. Name_Len
+ 5) := "__SDP";
4923 Name_Len
:= Name_Len
+ 5;
4925 Set_Is_Imported
(Ent
);
4926 Set_Interface_Name
(Ent
,
4927 Make_String_Literal
(Loc
,
4928 Strval
=> String_From_Name_Buffer
));
4930 -- Set entity as internal to ensure proper Sprint output of its
4931 -- implicit importation.
4933 Set_Is_Internal
(Ent
);
4936 Make_Attribute_Reference
(Loc
,
4937 Prefix
=> New_Occurrence_Of
(Ent
, Loc
),
4938 Attribute_Name
=> Name_Address
));
4940 Analyze_And_Resolve
(N
, Typ
);
4947 -- The processing for VADS_Size is shared with Size
4953 -- For enumeration types with a standard representation, and for all
4954 -- other types, Val is handled by the back end. For enumeration types
4955 -- with a non-standard representation we use the _Pos_To_Rep array that
4956 -- was created when the type was frozen.
4958 when Attribute_Val
=> Val
: declare
4959 Etyp
: constant Entity_Id
:= Base_Type
(Entity
(Pref
));
4962 if Is_Enumeration_Type
(Etyp
)
4963 and then Present
(Enum_Pos_To_Rep
(Etyp
))
4965 if Has_Contiguous_Rep
(Etyp
) then
4967 Rep_Node
: constant Node_Id
:=
4968 Unchecked_Convert_To
(Etyp
,
4971 Make_Integer_Literal
(Loc
,
4972 Enumeration_Rep
(First_Literal
(Etyp
))),
4974 (Convert_To
(Standard_Integer
,
4975 Relocate_Node
(First
(Exprs
))))));
4979 Unchecked_Convert_To
(Etyp
,
4982 Make_Integer_Literal
(Loc
,
4983 Enumeration_Rep
(First_Literal
(Etyp
))),
4985 Make_Function_Call
(Loc
,
4988 (TSS
(Etyp
, TSS_Rep_To_Pos
), Loc
),
4989 Parameter_Associations
=> New_List
(
4991 Rep_To_Pos_Flag
(Etyp
, Loc
))))));
4996 Make_Indexed_Component
(Loc
,
4997 Prefix
=> New_Reference_To
(Enum_Pos_To_Rep
(Etyp
), Loc
),
4998 Expressions
=> New_List
(
4999 Convert_To
(Standard_Integer
,
5000 Relocate_Node
(First
(Exprs
))))));
5003 Analyze_And_Resolve
(N
, Typ
);
5005 -- If the argument is marked as requiring a range check then generate
5008 elsif Do_Range_Check
(First
(Exprs
)) then
5009 Set_Do_Range_Check
(First
(Exprs
), False);
5010 Generate_Range_Check
(First
(Exprs
), Etyp
, CE_Range_Check_Failed
);
5018 -- The code for valid is dependent on the particular types involved.
5019 -- See separate sections below for the generated code in each case.
5021 when Attribute_Valid
=> Valid
: declare
5022 Btyp
: Entity_Id
:= Base_Type
(Ptyp
);
5025 Save_Validity_Checks_On
: constant Boolean := Validity_Checks_On
;
5026 -- Save the validity checking mode. We always turn off validity
5027 -- checking during process of 'Valid since this is one place
5028 -- where we do not want the implicit validity checks to intefere
5029 -- with the explicit validity check that the programmer is doing.
5031 function Make_Range_Test
return Node_Id
;
5032 -- Build the code for a range test of the form
5033 -- Btyp!(Pref) in Btyp!(Ptyp'First) .. Btyp!(Ptyp'Last)
5035 ---------------------
5036 -- Make_Range_Test --
5037 ---------------------
5039 function Make_Range_Test
return Node_Id
is
5040 Temp
: constant Node_Id
:= Duplicate_Subexpr
(Pref
);
5043 -- The value whose validity is being checked has been captured in
5044 -- an object declaration. We certainly don't want this object to
5045 -- appear valid because the declaration initializes it!
5047 if Is_Entity_Name
(Temp
) then
5048 Set_Is_Known_Valid
(Entity
(Temp
), False);
5054 Unchecked_Convert_To
(Btyp
, Temp
),
5058 Unchecked_Convert_To
(Btyp
,
5059 Make_Attribute_Reference
(Loc
,
5060 Prefix
=> New_Occurrence_Of
(Ptyp
, Loc
),
5061 Attribute_Name
=> Name_First
)),
5063 Unchecked_Convert_To
(Btyp
,
5064 Make_Attribute_Reference
(Loc
,
5065 Prefix
=> New_Occurrence_Of
(Ptyp
, Loc
),
5066 Attribute_Name
=> Name_Last
))));
5067 end Make_Range_Test
;
5069 -- Start of processing for Attribute_Valid
5072 -- Do not expand sourced code 'Valid reference in CodePeer mode,
5073 -- will be handled by the back-end directly.
5075 if CodePeer_Mode
and then Comes_From_Source
(N
) then
5079 -- Turn off validity checks. We do not want any implicit validity
5080 -- checks to intefere with the explicit check from the attribute
5082 Validity_Checks_On
:= False;
5084 -- Floating-point case. This case is handled by the Valid attribute
5085 -- code in the floating-point attribute run-time library.
5087 if Is_Floating_Point_Type
(Ptyp
) then
5094 case Float_Rep
(Btyp
) is
5096 -- For vax fpt types, call appropriate routine in special
5097 -- vax floating point unit. No need to worry about loads in
5098 -- this case, since these types have no signalling NaN's.
5100 when VAX_Native
=> Expand_Vax_Valid
(N
);
5102 -- The AAMP back end handles Valid for floating-point types
5105 Analyze_And_Resolve
(Pref
, Ptyp
);
5106 Set_Etype
(N
, Standard_Boolean
);
5110 Find_Fat_Info
(Ptyp
, Ftp
, Pkg
);
5112 -- If the floating-point object might be unaligned, we
5113 -- need to call the special routine Unaligned_Valid,
5114 -- which makes the needed copy, being careful not to
5115 -- load the value into any floating-point register.
5116 -- The argument in this case is obj'Address (see
5117 -- Unaligned_Valid routine in Fat_Gen).
5119 if Is_Possibly_Unaligned_Object
(Pref
) then
5120 Expand_Fpt_Attribute
5121 (N
, Pkg
, Name_Unaligned_Valid
,
5123 Make_Attribute_Reference
(Loc
,
5124 Prefix
=> Relocate_Node
(Pref
),
5125 Attribute_Name
=> Name_Address
)));
5127 -- In the normal case where we are sure the object is
5128 -- aligned, we generate a call to Valid, and the argument
5129 -- in this case is obj'Unrestricted_Access (after
5130 -- converting obj to the right floating-point type).
5133 Expand_Fpt_Attribute
5134 (N
, Pkg
, Name_Valid
,
5136 Make_Attribute_Reference
(Loc
,
5137 Prefix
=> Unchecked_Convert_To
(Ftp
, Pref
),
5138 Attribute_Name
=> Name_Unrestricted_Access
)));
5142 -- One more task, we still need a range check. Required
5143 -- only if we have a constraint, since the Valid routine
5144 -- catches infinities properly (infinities are never valid).
5146 -- The way we do the range check is simply to create the
5147 -- expression: Valid (N) and then Base_Type(Pref) in Typ.
5149 if not Subtypes_Statically_Match
(Ptyp
, Btyp
) then
5152 Left_Opnd
=> Relocate_Node
(N
),
5155 Left_Opnd
=> Convert_To
(Btyp
, Pref
),
5156 Right_Opnd
=> New_Occurrence_Of
(Ptyp
, Loc
))));
5160 -- Enumeration type with holes
5162 -- For enumeration types with holes, the Pos value constructed by
5163 -- the Enum_Rep_To_Pos function built in Exp_Ch3 called with a
5164 -- second argument of False returns minus one for an invalid value,
5165 -- and the non-negative pos value for a valid value, so the
5166 -- expansion of X'Valid is simply:
5168 -- type(X)'Pos (X) >= 0
5170 -- We can't quite generate it that way because of the requirement
5171 -- for the non-standard second argument of False in the resulting
5172 -- rep_to_pos call, so we have to explicitly create:
5174 -- _rep_to_pos (X, False) >= 0
5176 -- If we have an enumeration subtype, we also check that the
5177 -- value is in range:
5179 -- _rep_to_pos (X, False) >= 0
5181 -- (X >= type(X)'First and then type(X)'Last <= X)
5183 elsif Is_Enumeration_Type
(Ptyp
)
5184 and then Present
(Enum_Pos_To_Rep
(Base_Type
(Ptyp
)))
5189 Make_Function_Call
(Loc
,
5192 (TSS
(Base_Type
(Ptyp
), TSS_Rep_To_Pos
), Loc
),
5193 Parameter_Associations
=> New_List
(
5195 New_Occurrence_Of
(Standard_False
, Loc
))),
5196 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0));
5200 (Type_Low_Bound
(Ptyp
) /= Type_Low_Bound
(Btyp
)
5202 Type_High_Bound
(Ptyp
) /= Type_High_Bound
(Btyp
))
5204 -- The call to Make_Range_Test will create declarations
5205 -- that need a proper insertion point, but Pref is now
5206 -- attached to a node with no ancestor. Attach to tree
5207 -- even if it is to be rewritten below.
5209 Set_Parent
(Tst
, Parent
(N
));
5213 Left_Opnd
=> Make_Range_Test
,
5219 -- Fortran convention booleans
5221 -- For the very special case of Fortran convention booleans, the
5222 -- value is always valid, since it is an integer with the semantics
5223 -- that non-zero is true, and any value is permissible.
5225 elsif Is_Boolean_Type
(Ptyp
)
5226 and then Convention
(Ptyp
) = Convention_Fortran
5228 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
5230 -- For biased representations, we will be doing an unchecked
5231 -- conversion without unbiasing the result. That means that the range
5232 -- test has to take this into account, and the proper form of the
5235 -- Btyp!(Pref) < Btyp!(Ptyp'Range_Length)
5237 elsif Has_Biased_Representation
(Ptyp
) then
5238 Btyp
:= RTE
(RE_Unsigned_32
);
5242 Unchecked_Convert_To
(Btyp
, Duplicate_Subexpr
(Pref
)),
5244 Unchecked_Convert_To
(Btyp
,
5245 Make_Attribute_Reference
(Loc
,
5246 Prefix
=> New_Occurrence_Of
(Ptyp
, Loc
),
5247 Attribute_Name
=> Name_Range_Length
))));
5249 -- For all other scalar types, what we want logically is a
5252 -- X in type(X)'First .. type(X)'Last
5254 -- But that's precisely what won't work because of possible
5255 -- unwanted optimization (and indeed the basic motivation for
5256 -- the Valid attribute is exactly that this test does not work!)
5257 -- What will work is:
5259 -- Btyp!(X) >= Btyp!(type(X)'First)
5261 -- Btyp!(X) <= Btyp!(type(X)'Last)
5263 -- where Btyp is an integer type large enough to cover the full
5264 -- range of possible stored values (i.e. it is chosen on the basis
5265 -- of the size of the type, not the range of the values). We write
5266 -- this as two tests, rather than a range check, so that static
5267 -- evaluation will easily remove either or both of the checks if
5268 -- they can be -statically determined to be true (this happens
5269 -- when the type of X is static and the range extends to the full
5270 -- range of stored values).
5272 -- Unsigned types. Note: it is safe to consider only whether the
5273 -- subtype is unsigned, since we will in that case be doing all
5274 -- unsigned comparisons based on the subtype range. Since we use the
5275 -- actual subtype object size, this is appropriate.
5277 -- For example, if we have
5279 -- subtype x is integer range 1 .. 200;
5280 -- for x'Object_Size use 8;
5282 -- Now the base type is signed, but objects of this type are bits
5283 -- unsigned, and doing an unsigned test of the range 1 to 200 is
5284 -- correct, even though a value greater than 127 looks signed to a
5285 -- signed comparison.
5287 elsif Is_Unsigned_Type
(Ptyp
) then
5288 if Esize
(Ptyp
) <= 32 then
5289 Btyp
:= RTE
(RE_Unsigned_32
);
5291 Btyp
:= RTE
(RE_Unsigned_64
);
5294 Rewrite
(N
, Make_Range_Test
);
5299 if Esize
(Ptyp
) <= Esize
(Standard_Integer
) then
5300 Btyp
:= Standard_Integer
;
5302 Btyp
:= Universal_Integer
;
5305 Rewrite
(N
, Make_Range_Test
);
5308 Analyze_And_Resolve
(N
, Standard_Boolean
);
5309 Validity_Checks_On
:= Save_Validity_Checks_On
;
5316 -- Value attribute is handled in separate unit Exp_Imgv
5318 when Attribute_Value
=>
5319 Exp_Imgv
.Expand_Value_Attribute
(N
);
5325 -- The processing for Value_Size shares the processing for Size
5331 -- The processing for Version shares the processing for Body_Version
5337 -- Wide_Image attribute is handled in separate unit Exp_Imgv
5339 when Attribute_Wide_Image
=>
5340 Exp_Imgv
.Expand_Wide_Image_Attribute
(N
);
5342 ---------------------
5343 -- Wide_Wide_Image --
5344 ---------------------
5346 -- Wide_Wide_Image attribute is handled in separate unit Exp_Imgv
5348 when Attribute_Wide_Wide_Image
=>
5349 Exp_Imgv
.Expand_Wide_Wide_Image_Attribute
(N
);
5355 -- We expand typ'Wide_Value (X) into
5358 -- (Wide_String_To_String (X, Wide_Character_Encoding_Method))
5360 -- Wide_String_To_String is a runtime function that converts its wide
5361 -- string argument to String, converting any non-translatable characters
5362 -- into appropriate escape sequences. This preserves the required
5363 -- semantics of Wide_Value in all cases, and results in a very simple
5364 -- implementation approach.
5366 -- Note: for this approach to be fully standard compliant for the cases
5367 -- where typ is Wide_Character and Wide_Wide_Character, the encoding
5368 -- method must cover the entire character range (e.g. UTF-8). But that
5369 -- is a reasonable requirement when dealing with encoded character
5370 -- sequences. Presumably if one of the restrictive encoding mechanisms
5371 -- is in use such as Shift-JIS, then characters that cannot be
5372 -- represented using this encoding will not appear in any case.
5374 when Attribute_Wide_Value
=> Wide_Value
:
5377 Make_Attribute_Reference
(Loc
,
5379 Attribute_Name
=> Name_Value
,
5381 Expressions
=> New_List
(
5382 Make_Function_Call
(Loc
,
5384 New_Reference_To
(RTE
(RE_Wide_String_To_String
), Loc
),
5386 Parameter_Associations
=> New_List
(
5387 Relocate_Node
(First
(Exprs
)),
5388 Make_Integer_Literal
(Loc
,
5389 Intval
=> Int
(Wide_Character_Encoding_Method
)))))));
5391 Analyze_And_Resolve
(N
, Typ
);
5394 ---------------------
5395 -- Wide_Wide_Value --
5396 ---------------------
5398 -- We expand typ'Wide_Value_Value (X) into
5401 -- (Wide_Wide_String_To_String (X, Wide_Character_Encoding_Method))
5403 -- Wide_Wide_String_To_String is a runtime function that converts its
5404 -- wide string argument to String, converting any non-translatable
5405 -- characters into appropriate escape sequences. This preserves the
5406 -- required semantics of Wide_Wide_Value in all cases, and results in a
5407 -- very simple implementation approach.
5409 -- It's not quite right where typ = Wide_Wide_Character, because the
5410 -- encoding method may not cover the whole character type ???
5412 when Attribute_Wide_Wide_Value
=> Wide_Wide_Value
:
5415 Make_Attribute_Reference
(Loc
,
5417 Attribute_Name
=> Name_Value
,
5419 Expressions
=> New_List
(
5420 Make_Function_Call
(Loc
,
5422 New_Reference_To
(RTE
(RE_Wide_Wide_String_To_String
), Loc
),
5424 Parameter_Associations
=> New_List
(
5425 Relocate_Node
(First
(Exprs
)),
5426 Make_Integer_Literal
(Loc
,
5427 Intval
=> Int
(Wide_Character_Encoding_Method
)))))));
5429 Analyze_And_Resolve
(N
, Typ
);
5430 end Wide_Wide_Value
;
5432 ---------------------
5433 -- Wide_Wide_Width --
5434 ---------------------
5436 -- Wide_Wide_Width attribute is handled in separate unit Exp_Imgv
5438 when Attribute_Wide_Wide_Width
=>
5439 Exp_Imgv
.Expand_Width_Attribute
(N
, Wide_Wide
);
5445 -- Wide_Width attribute is handled in separate unit Exp_Imgv
5447 when Attribute_Wide_Width
=>
5448 Exp_Imgv
.Expand_Width_Attribute
(N
, Wide
);
5454 -- Width attribute is handled in separate unit Exp_Imgv
5456 when Attribute_Width
=>
5457 Exp_Imgv
.Expand_Width_Attribute
(N
, Normal
);
5463 when Attribute_Write
=> Write
: declare
5464 P_Type
: constant Entity_Id
:= Entity
(Pref
);
5465 U_Type
: constant Entity_Id
:= Underlying_Type
(P_Type
);
5473 -- If no underlying type, we have an error that will be diagnosed
5474 -- elsewhere, so here we just completely ignore the expansion.
5480 -- The simple case, if there is a TSS for Write, just call it
5482 Pname
:= Find_Stream_Subprogram
(P_Type
, TSS_Stream_Write
);
5484 if Present
(Pname
) then
5488 -- If there is a Stream_Convert pragma, use it, we rewrite
5490 -- sourcetyp'Output (stream, Item)
5494 -- strmtyp'Output (Stream, strmwrite (acttyp (Item)));
5496 -- where strmwrite is the given Write function that converts an
5497 -- argument of type sourcetyp or a type acctyp, from which it is
5498 -- derived to type strmtyp. The conversion to acttyp is required
5499 -- for the derived case.
5501 Prag
:= Get_Stream_Convert_Pragma
(P_Type
);
5503 if Present
(Prag
) then
5505 Next
(Next
(First
(Pragma_Argument_Associations
(Prag
))));
5506 Wfunc
:= Entity
(Expression
(Arg3
));
5509 Make_Attribute_Reference
(Loc
,
5510 Prefix
=> New_Occurrence_Of
(Etype
(Wfunc
), Loc
),
5511 Attribute_Name
=> Name_Output
,
5512 Expressions
=> New_List
(
5513 Relocate_Node
(First
(Exprs
)),
5514 Make_Function_Call
(Loc
,
5515 Name
=> New_Occurrence_Of
(Wfunc
, Loc
),
5516 Parameter_Associations
=> New_List
(
5517 OK_Convert_To
(Etype
(First_Formal
(Wfunc
)),
5518 Relocate_Node
(Next
(First
(Exprs
)))))))));
5523 -- For elementary types, we call the W_xxx routine directly
5525 elsif Is_Elementary_Type
(U_Type
) then
5526 Rewrite
(N
, Build_Elementary_Write_Call
(N
));
5532 elsif Is_Array_Type
(U_Type
) then
5533 Build_Array_Write_Procedure
(N
, U_Type
, Decl
, Pname
);
5534 Compile_Stream_Body_In_Scope
(N
, Decl
, U_Type
, Check
=> False);
5536 -- Tagged type case, use the primitive Write function. Note that
5537 -- this will dispatch in the class-wide case which is what we want
5539 elsif Is_Tagged_Type
(U_Type
) then
5540 Pname
:= Find_Prim_Op
(U_Type
, TSS_Stream_Write
);
5542 -- All other record type cases, including protected records.
5543 -- The latter only arise for expander generated code for
5544 -- handling shared passive partition access.
5548 (Is_Record_Type
(U_Type
) or else Is_Protected_Type
(U_Type
));
5550 -- Ada 2005 (AI-216): Program_Error is raised when executing
5551 -- the default implementation of the Write attribute of an
5552 -- Unchecked_Union type. However, if the 'Write reference is
5553 -- within the generated Output stream procedure, Write outputs
5554 -- the components, and the default values of the discriminant
5555 -- are streamed by the Output procedure itself.
5557 if Is_Unchecked_Union
(Base_Type
(U_Type
))
5558 and not Is_TSS
(Current_Scope
, TSS_Stream_Output
)
5561 Make_Raise_Program_Error
(Loc
,
5562 Reason
=> PE_Unchecked_Union_Restriction
));
5565 if Has_Discriminants
(U_Type
)
5567 (Discriminant_Default_Value
(First_Discriminant
(U_Type
)))
5569 Build_Mutable_Record_Write_Procedure
5570 (Loc
, Full_Base
(U_Type
), Decl
, Pname
);
5572 Build_Record_Write_Procedure
5573 (Loc
, Full_Base
(U_Type
), Decl
, Pname
);
5576 Insert_Action
(N
, Decl
);
5580 -- If we fall through, Pname is the procedure to be called
5582 Rewrite_Stream_Proc_Call
(Pname
);
5585 -- Component_Size is handled by the back end, unless the component size
5586 -- is known at compile time, which is always true in the packed array
5587 -- case. It is important that the packed array case is handled in the
5588 -- front end (see Eval_Attribute) since the back end would otherwise get
5589 -- confused by the equivalent packed array type.
5591 when Attribute_Component_Size
=>
5594 -- The following attributes are handled by the back end (except that
5595 -- static cases have already been evaluated during semantic processing,
5596 -- but in any case the back end should not count on this). The one bit
5597 -- of special processing required is that these attributes typically
5598 -- generate conditionals in the code, so we need to check the relevant
5601 when Attribute_Max |
5603 Check_Restriction
(No_Implicit_Conditionals
, N
);
5605 -- The following attributes are handled by the back end (except that
5606 -- static cases have already been evaluated during semantic processing,
5607 -- but in any case the back end should not count on this).
5609 -- The back end also handles the non-class-wide cases of Size
5611 when Attribute_Bit_Order |
5612 Attribute_Code_Address |
5613 Attribute_Definite |
5614 Attribute_Null_Parameter |
5615 Attribute_Passed_By_Reference |
5616 Attribute_Pool_Address
=>
5619 -- The following attributes are also handled by the back end, but return
5620 -- a universal integer result, so may need a conversion for checking
5621 -- that the result is in range.
5623 when Attribute_Aft |
5624 Attribute_Max_Alignment_For_Allocation
=>
5625 Apply_Universal_Integer_Attribute_Checks
(N
);
5627 -- The following attributes should not appear at this stage, since they
5628 -- have already been handled by the analyzer (and properly rewritten
5629 -- with corresponding values or entities to represent the right values)
5631 when Attribute_Abort_Signal |
5632 Attribute_Address_Size |
5635 Attribute_Compiler_Version |
5636 Attribute_Default_Bit_Order |
5643 Attribute_Fast_Math |
5644 Attribute_Has_Access_Values |
5645 Attribute_Has_Discriminants |
5646 Attribute_Has_Tagged_Values |
5648 Attribute_Machine_Emax |
5649 Attribute_Machine_Emin |
5650 Attribute_Machine_Mantissa |
5651 Attribute_Machine_Overflows |
5652 Attribute_Machine_Radix |
5653 Attribute_Machine_Rounds |
5654 Attribute_Maximum_Alignment |
5655 Attribute_Model_Emin |
5656 Attribute_Model_Epsilon |
5657 Attribute_Model_Mantissa |
5658 Attribute_Model_Small |
5660 Attribute_Partition_ID |
5662 Attribute_Safe_Emax |
5663 Attribute_Safe_First |
5664 Attribute_Safe_Large |
5665 Attribute_Safe_Last |
5666 Attribute_Safe_Small |
5668 Attribute_Signed_Zeros |
5670 Attribute_Storage_Unit |
5671 Attribute_Stub_Type |
5672 Attribute_System_Allocator_Alignment |
5673 Attribute_Target_Name |
5674 Attribute_Type_Class |
5675 Attribute_Type_Key |
5676 Attribute_Unconstrained_Array |
5677 Attribute_Universal_Literal_String |
5678 Attribute_Wchar_T_Size |
5679 Attribute_Word_Size
=>
5680 raise Program_Error
;
5682 -- The Asm_Input and Asm_Output attributes are not expanded at this
5683 -- stage, but will be eliminated in the expansion of the Asm call, see
5684 -- Exp_Intr for details. So the back end will never see these either.
5686 when Attribute_Asm_Input |
5687 Attribute_Asm_Output
=>
5692 when RE_Not_Available
=>
5694 end Expand_N_Attribute_Reference
;
5696 ----------------------
5697 -- Expand_Pred_Succ --
5698 ----------------------
5700 -- For typ'Pred (exp), we generate the check
5702 -- [constraint_error when exp = typ'Base'First]
5704 -- Similarly, for typ'Succ (exp), we generate the check
5706 -- [constraint_error when exp = typ'Base'Last]
5708 -- These checks are not generated for modular types, since the proper
5709 -- semantics for Succ and Pred on modular types is to wrap, not raise CE.
5710 -- We also suppress these checks if we are the right side of an assignment
5711 -- statement or the expression of an object declaration, where the flag
5712 -- Suppress_Assignment_Checks is set for the assignment/declaration.
5714 procedure Expand_Pred_Succ
(N
: Node_Id
) is
5715 Loc
: constant Source_Ptr
:= Sloc
(N
);
5716 P
: constant Node_Id
:= Parent
(N
);
5720 if Attribute_Name
(N
) = Name_Pred
then
5726 if not Nkind_In
(P
, N_Assignment_Statement
, N_Object_Declaration
)
5727 or else not Suppress_Assignment_Checks
(P
)
5730 Make_Raise_Constraint_Error
(Loc
,
5734 Duplicate_Subexpr_Move_Checks
(First
(Expressions
(N
))),
5736 Make_Attribute_Reference
(Loc
,
5738 New_Reference_To
(Base_Type
(Etype
(Prefix
(N
))), Loc
),
5739 Attribute_Name
=> Cnam
)),
5740 Reason
=> CE_Overflow_Check_Failed
));
5742 end Expand_Pred_Succ
;
5748 procedure Find_Fat_Info
5750 Fat_Type
: out Entity_Id
;
5751 Fat_Pkg
: out RE_Id
)
5753 Btyp
: constant Entity_Id
:= Base_Type
(T
);
5754 Rtyp
: constant Entity_Id
:= Root_Type
(T
);
5755 Digs
: constant Nat
:= UI_To_Int
(Digits_Value
(Btyp
));
5758 -- If the base type is VAX float, then get appropriate VAX float type
5760 if Vax_Float
(Btyp
) then
5763 Fat_Type
:= RTE
(RE_Fat_VAX_F
);
5764 Fat_Pkg
:= RE_Attr_VAX_F_Float
;
5767 Fat_Type
:= RTE
(RE_Fat_VAX_D
);
5768 Fat_Pkg
:= RE_Attr_VAX_D_Float
;
5771 Fat_Type
:= RTE
(RE_Fat_VAX_G
);
5772 Fat_Pkg
:= RE_Attr_VAX_G_Float
;
5775 raise Program_Error
;
5778 -- If root type is VAX float, this is the case where the library has
5779 -- been recompiled in VAX float mode, and we have an IEEE float type.
5780 -- This is when we use the special IEEE Fat packages.
5782 elsif Vax_Float
(Rtyp
) then
5785 Fat_Type
:= RTE
(RE_Fat_IEEE_Short
);
5786 Fat_Pkg
:= RE_Attr_IEEE_Short
;
5789 Fat_Type
:= RTE
(RE_Fat_IEEE_Long
);
5790 Fat_Pkg
:= RE_Attr_IEEE_Long
;
5793 raise Program_Error
;
5796 -- If neither the base type nor the root type is VAX_Native then VAX
5797 -- float is out of the picture, and we can just use the root type.
5802 if Fat_Type
= Standard_Short_Float
then
5803 Fat_Pkg
:= RE_Attr_Short_Float
;
5805 elsif Fat_Type
= Standard_Float
then
5806 Fat_Pkg
:= RE_Attr_Float
;
5808 elsif Fat_Type
= Standard_Long_Float
then
5809 Fat_Pkg
:= RE_Attr_Long_Float
;
5811 elsif Fat_Type
= Standard_Long_Long_Float
then
5812 Fat_Pkg
:= RE_Attr_Long_Long_Float
;
5814 -- Universal real (which is its own root type) is treated as being
5815 -- equivalent to Standard.Long_Long_Float, since it is defined to
5816 -- have the same precision as the longest Float type.
5818 elsif Fat_Type
= Universal_Real
then
5819 Fat_Type
:= Standard_Long_Long_Float
;
5820 Fat_Pkg
:= RE_Attr_Long_Long_Float
;
5823 raise Program_Error
;
5828 ----------------------------
5829 -- Find_Stream_Subprogram --
5830 ----------------------------
5832 function Find_Stream_Subprogram
5834 Nam
: TSS_Name_Type
) return Entity_Id
5836 Base_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
5837 Ent
: constant Entity_Id
:= TSS
(Typ
, Nam
);
5839 function Is_Available
(Entity
: RE_Id
) return Boolean;
5840 pragma Inline
(Is_Available
);
5841 -- Function to check whether the specified run-time call is available
5842 -- in the run time used. In the case of a configurable run time, it
5843 -- is normal that some subprograms are not there.
5845 -- I don't understand this routine at all, why is this not just a
5846 -- call to RTE_Available? And if for some reason we need a different
5847 -- routine with different semantics, why is not in Rtsfind ???
5853 function Is_Available
(Entity
: RE_Id
) return Boolean is
5855 -- Assume that the unit will always be available when using a
5856 -- "normal" (not configurable) run time.
5858 return not Configurable_Run_Time_Mode
5859 or else RTE_Available
(Entity
);
5862 -- Start of processing for Find_Stream_Subprogram
5865 if Present
(Ent
) then
5869 -- Stream attributes for strings are expanded into library calls. The
5870 -- following checks are disabled when the run-time is not available or
5871 -- when compiling predefined types due to bootstrap issues. As a result,
5872 -- the compiler will generate in-place stream routines for string types
5873 -- that appear in GNAT's library, but will generate calls via rtsfind
5874 -- to library routines for user code.
5876 -- ??? For now, disable this code for JVM, since this generates a
5877 -- VerifyError exception at run time on e.g. c330001.
5879 -- This is disabled for AAMP, to avoid creating dependences on files not
5880 -- supported in the AAMP library (such as s-fileio.adb).
5882 -- Note: In the case of using a configurable run time, it is very likely
5883 -- that stream routines for string types are not present (they require
5884 -- file system support). In this case, the specific stream routines for
5885 -- strings are not used, relying on the regular stream mechanism
5886 -- instead. That is why we include the test Is_Available when dealing
5887 -- with these cases.
5889 if VM_Target
/= JVM_Target
5890 and then not AAMP_On_Target
5892 not Is_Predefined_File_Name
(Unit_File_Name
(Current_Sem_Unit
))
5894 -- String as defined in package Ada
5896 if Base_Typ
= Standard_String
then
5897 if Restriction_Active
(No_Stream_Optimizations
) then
5898 if Nam
= TSS_Stream_Input
5899 and then Is_Available
(RE_String_Input
)
5901 return RTE
(RE_String_Input
);
5903 elsif Nam
= TSS_Stream_Output
5904 and then Is_Available
(RE_String_Output
)
5906 return RTE
(RE_String_Output
);
5908 elsif Nam
= TSS_Stream_Read
5909 and then Is_Available
(RE_String_Read
)
5911 return RTE
(RE_String_Read
);
5913 elsif Nam
= TSS_Stream_Write
5914 and then Is_Available
(RE_String_Write
)
5916 return RTE
(RE_String_Write
);
5918 elsif Nam
/= TSS_Stream_Input
and then
5919 Nam
/= TSS_Stream_Output
and then
5920 Nam
/= TSS_Stream_Read
and then
5921 Nam
/= TSS_Stream_Write
5923 raise Program_Error
;
5927 if Nam
= TSS_Stream_Input
5928 and then Is_Available
(RE_String_Input_Blk_IO
)
5930 return RTE
(RE_String_Input_Blk_IO
);
5932 elsif Nam
= TSS_Stream_Output
5933 and then Is_Available
(RE_String_Output_Blk_IO
)
5935 return RTE
(RE_String_Output_Blk_IO
);
5937 elsif Nam
= TSS_Stream_Read
5938 and then Is_Available
(RE_String_Read_Blk_IO
)
5940 return RTE
(RE_String_Read_Blk_IO
);
5942 elsif Nam
= TSS_Stream_Write
5943 and then Is_Available
(RE_String_Write_Blk_IO
)
5945 return RTE
(RE_String_Write_Blk_IO
);
5947 elsif Nam
/= TSS_Stream_Input
and then
5948 Nam
/= TSS_Stream_Output
and then
5949 Nam
/= TSS_Stream_Read
and then
5950 Nam
/= TSS_Stream_Write
5952 raise Program_Error
;
5956 -- Wide_String as defined in package Ada
5958 elsif Base_Typ
= Standard_Wide_String
then
5959 if Restriction_Active
(No_Stream_Optimizations
) then
5960 if Nam
= TSS_Stream_Input
5961 and then Is_Available
(RE_Wide_String_Input
)
5963 return RTE
(RE_Wide_String_Input
);
5965 elsif Nam
= TSS_Stream_Output
5966 and then Is_Available
(RE_Wide_String_Output
)
5968 return RTE
(RE_Wide_String_Output
);
5970 elsif Nam
= TSS_Stream_Read
5971 and then Is_Available
(RE_Wide_String_Read
)
5973 return RTE
(RE_Wide_String_Read
);
5975 elsif Nam
= TSS_Stream_Write
5976 and then Is_Available
(RE_Wide_String_Write
)
5978 return RTE
(RE_Wide_String_Write
);
5980 elsif Nam
/= TSS_Stream_Input
and then
5981 Nam
/= TSS_Stream_Output
and then
5982 Nam
/= TSS_Stream_Read
and then
5983 Nam
/= TSS_Stream_Write
5985 raise Program_Error
;
5989 if Nam
= TSS_Stream_Input
5990 and then Is_Available
(RE_Wide_String_Input_Blk_IO
)
5992 return RTE
(RE_Wide_String_Input_Blk_IO
);
5994 elsif Nam
= TSS_Stream_Output
5995 and then Is_Available
(RE_Wide_String_Output_Blk_IO
)
5997 return RTE
(RE_Wide_String_Output_Blk_IO
);
5999 elsif Nam
= TSS_Stream_Read
6000 and then Is_Available
(RE_Wide_String_Read_Blk_IO
)
6002 return RTE
(RE_Wide_String_Read_Blk_IO
);
6004 elsif Nam
= TSS_Stream_Write
6005 and then Is_Available
(RE_Wide_String_Write_Blk_IO
)
6007 return RTE
(RE_Wide_String_Write_Blk_IO
);
6009 elsif Nam
/= TSS_Stream_Input
and then
6010 Nam
/= TSS_Stream_Output
and then
6011 Nam
/= TSS_Stream_Read
and then
6012 Nam
/= TSS_Stream_Write
6014 raise Program_Error
;
6018 -- Wide_Wide_String as defined in package Ada
6020 elsif Base_Typ
= Standard_Wide_Wide_String
then
6021 if Restriction_Active
(No_Stream_Optimizations
) then
6022 if Nam
= TSS_Stream_Input
6023 and then Is_Available
(RE_Wide_Wide_String_Input
)
6025 return RTE
(RE_Wide_Wide_String_Input
);
6027 elsif Nam
= TSS_Stream_Output
6028 and then Is_Available
(RE_Wide_Wide_String_Output
)
6030 return RTE
(RE_Wide_Wide_String_Output
);
6032 elsif Nam
= TSS_Stream_Read
6033 and then Is_Available
(RE_Wide_Wide_String_Read
)
6035 return RTE
(RE_Wide_Wide_String_Read
);
6037 elsif Nam
= TSS_Stream_Write
6038 and then Is_Available
(RE_Wide_Wide_String_Write
)
6040 return RTE
(RE_Wide_Wide_String_Write
);
6042 elsif Nam
/= TSS_Stream_Input
and then
6043 Nam
/= TSS_Stream_Output
and then
6044 Nam
/= TSS_Stream_Read
and then
6045 Nam
/= TSS_Stream_Write
6047 raise Program_Error
;
6051 if Nam
= TSS_Stream_Input
6052 and then Is_Available
(RE_Wide_Wide_String_Input_Blk_IO
)
6054 return RTE
(RE_Wide_Wide_String_Input_Blk_IO
);
6056 elsif Nam
= TSS_Stream_Output
6057 and then Is_Available
(RE_Wide_Wide_String_Output_Blk_IO
)
6059 return RTE
(RE_Wide_Wide_String_Output_Blk_IO
);
6061 elsif Nam
= TSS_Stream_Read
6062 and then Is_Available
(RE_Wide_Wide_String_Read_Blk_IO
)
6064 return RTE
(RE_Wide_Wide_String_Read_Blk_IO
);
6066 elsif Nam
= TSS_Stream_Write
6067 and then Is_Available
(RE_Wide_Wide_String_Write_Blk_IO
)
6069 return RTE
(RE_Wide_Wide_String_Write_Blk_IO
);
6071 elsif Nam
/= TSS_Stream_Input
and then
6072 Nam
/= TSS_Stream_Output
and then
6073 Nam
/= TSS_Stream_Read
and then
6074 Nam
/= TSS_Stream_Write
6076 raise Program_Error
;
6082 if Is_Tagged_Type
(Typ
)
6083 and then Is_Derived_Type
(Typ
)
6085 return Find_Prim_Op
(Typ
, Nam
);
6087 return Find_Inherited_TSS
(Typ
, Nam
);
6089 end Find_Stream_Subprogram
;
6095 function Full_Base
(T
: Entity_Id
) return Entity_Id
is
6099 BT
:= Base_Type
(T
);
6101 if Is_Private_Type
(BT
)
6102 and then Present
(Full_View
(BT
))
6104 BT
:= Full_View
(BT
);
6110 -----------------------
6111 -- Get_Index_Subtype --
6112 -----------------------
6114 function Get_Index_Subtype
(N
: Node_Id
) return Node_Id
is
6115 P_Type
: Entity_Id
:= Etype
(Prefix
(N
));
6120 if Is_Access_Type
(P_Type
) then
6121 P_Type
:= Designated_Type
(P_Type
);
6124 if No
(Expressions
(N
)) then
6127 J
:= UI_To_Int
(Expr_Value
(First
(Expressions
(N
))));
6130 Indx
:= First_Index
(P_Type
);
6136 return Etype
(Indx
);
6137 end Get_Index_Subtype
;
6139 -------------------------------
6140 -- Get_Stream_Convert_Pragma --
6141 -------------------------------
6143 function Get_Stream_Convert_Pragma
(T
: Entity_Id
) return Node_Id
is
6148 -- Note: we cannot use Get_Rep_Pragma here because of the peculiarity
6149 -- that a stream convert pragma for a tagged type is not inherited from
6150 -- its parent. Probably what is wrong here is that it is basically
6151 -- incorrect to consider a stream convert pragma to be a representation
6152 -- pragma at all ???
6154 N
:= First_Rep_Item
(Implementation_Base_Type
(T
));
6155 while Present
(N
) loop
6156 if Nkind
(N
) = N_Pragma
6157 and then Pragma_Name
(N
) = Name_Stream_Convert
6159 -- For tagged types this pragma is not inherited, so we
6160 -- must verify that it is defined for the given type and
6164 Entity
(Expression
(First
(Pragma_Argument_Associations
(N
))));
6166 if not Is_Tagged_Type
(T
)
6168 or else (Is_Private_Type
(Typ
) and then T
= Full_View
(Typ
))
6178 end Get_Stream_Convert_Pragma
;
6180 ---------------------------------
6181 -- Is_Constrained_Packed_Array --
6182 ---------------------------------
6184 function Is_Constrained_Packed_Array
(Typ
: Entity_Id
) return Boolean is
6185 Arr
: Entity_Id
:= Typ
;
6188 if Is_Access_Type
(Arr
) then
6189 Arr
:= Designated_Type
(Arr
);
6192 return Is_Array_Type
(Arr
)
6193 and then Is_Constrained
(Arr
)
6194 and then Present
(Packed_Array_Type
(Arr
));
6195 end Is_Constrained_Packed_Array
;
6197 ----------------------------------------
6198 -- Is_Inline_Floating_Point_Attribute --
6199 ----------------------------------------
6201 function Is_Inline_Floating_Point_Attribute
(N
: Node_Id
) return Boolean is
6202 Id
: constant Attribute_Id
:= Get_Attribute_Id
(Attribute_Name
(N
));
6205 if Nkind
(Parent
(N
)) /= N_Type_Conversion
6206 or else not Is_Integer_Type
(Etype
(Parent
(N
)))
6211 -- Should also support 'Machine_Rounding and 'Unbiased_Rounding, but
6212 -- required back end support has not been implemented yet ???
6214 return Id
= Attribute_Truncation
;
6215 end Is_Inline_Floating_Point_Attribute
;