1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2006, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree
; use Atree
;
28 with Casing
; use Casing
;
29 with Einfo
; use Einfo
;
30 with Errout
; use Errout
;
31 with Exp_Ch11
; use Exp_Ch11
;
32 with Exp_Tss
; use Exp_Tss
;
33 with Exp_Util
; use Exp_Util
;
34 with Expander
; use Expander
;
35 with Namet
; use Namet
;
36 with Nlists
; use Nlists
;
37 with Nmake
; use Nmake
;
39 with Rtsfind
; use Rtsfind
;
41 with Sem_Eval
; use Sem_Eval
;
42 with Sem_Res
; use Sem_Res
;
43 with Sem_Util
; use Sem_Util
;
44 with Sinfo
; use Sinfo
;
45 with Sinput
; use Sinput
;
46 with Snames
; use Snames
;
47 with Stringt
; use Stringt
;
48 with Stand
; use Stand
;
49 with Targparm
; use Targparm
;
50 with Tbuild
; use Tbuild
;
51 with Uintp
; use Uintp
;
53 package body Exp_Prag
is
55 -----------------------
56 -- Local Subprograms --
57 -----------------------
59 function Arg1
(N
: Node_Id
) return Node_Id
;
60 function Arg2
(N
: Node_Id
) return Node_Id
;
61 -- Obtain specified pragma argument expression
63 procedure Expand_Pragma_Abort_Defer
(N
: Node_Id
);
64 procedure Expand_Pragma_Assert
(N
: Node_Id
);
65 procedure Expand_Pragma_Common_Object
(N
: Node_Id
);
66 procedure Expand_Pragma_Import_Or_Interface
(N
: Node_Id
);
67 procedure Expand_Pragma_Import_Export_Exception
(N
: Node_Id
);
68 procedure Expand_Pragma_Inspection_Point
(N
: Node_Id
);
69 procedure Expand_Pragma_Interrupt_Priority
(N
: Node_Id
);
70 procedure Expand_Pragma_Psect_Object
(N
: Node_Id
);
76 function Arg1
(N
: Node_Id
) return Node_Id
is
77 Arg
: constant Node_Id
:= First
(Pragma_Argument_Associations
(N
));
80 and then Nkind
(Arg
) = N_Pragma_Argument_Association
82 return Expression
(Arg
);
92 function Arg2
(N
: Node_Id
) return Node_Id
is
93 Arg1
: constant Node_Id
:= First
(Pragma_Argument_Associations
(N
));
99 Arg
: constant Node_Id
:= Next
(Arg1
);
102 and then Nkind
(Arg
) = N_Pragma_Argument_Association
104 return Expression
(Arg
);
112 ---------------------
113 -- Expand_N_Pragma --
114 ---------------------
116 procedure Expand_N_Pragma
(N
: Node_Id
) is
118 -- Note: we may have a pragma whose chars field is not a
119 -- recognized pragma, and we must ignore it at this stage.
121 if Is_Pragma_Name
(Chars
(N
)) then
122 case Get_Pragma_Id
(Chars
(N
)) is
124 -- Pragmas requiring special expander action
126 when Pragma_Abort_Defer
=>
127 Expand_Pragma_Abort_Defer
(N
);
129 when Pragma_Assert
=>
130 Expand_Pragma_Assert
(N
);
132 when Pragma_Common_Object
=>
133 Expand_Pragma_Common_Object
(N
);
135 when Pragma_Export_Exception
=>
136 Expand_Pragma_Import_Export_Exception
(N
);
138 when Pragma_Import
=>
139 Expand_Pragma_Import_Or_Interface
(N
);
141 when Pragma_Import_Exception
=>
142 Expand_Pragma_Import_Export_Exception
(N
);
144 when Pragma_Inspection_Point
=>
145 Expand_Pragma_Inspection_Point
(N
);
147 when Pragma_Interface
=>
148 Expand_Pragma_Import_Or_Interface
(N
);
150 when Pragma_Interrupt_Priority
=>
151 Expand_Pragma_Interrupt_Priority
(N
);
153 when Pragma_Psect_Object
=>
154 Expand_Pragma_Psect_Object
(N
);
156 -- All other pragmas need no expander action
164 -------------------------------
165 -- Expand_Pragma_Abort_Defer --
166 -------------------------------
168 -- An Abort_Defer pragma appears as the first statement in a handled
169 -- statement sequence (right after the begin). It defers aborts for
170 -- the entire statement sequence, but not for any declarations or
171 -- handlers (if any) associated with this statement sequence.
173 -- The transformation is to transform
175 -- pragma Abort_Defer;
184 -- when all others =>
185 -- Abort_Undefer.all;
188 -- Abort_Undefer_Direct;
191 procedure Expand_Pragma_Abort_Defer
(N
: Node_Id
) is
192 Loc
: constant Source_Ptr
:= Sloc
(N
);
196 Blk
: constant Entity_Id
:=
197 New_Internal_Entity
(E_Block
, Current_Scope
, Sloc
(N
), 'B');
200 Stms
:= New_List
(Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
203 Stm
:= Remove_Next
(N
);
209 Make_Handled_Sequence_Of_Statements
(Loc
,
212 New_Occurrence_Of
(RTE
(RE_Abort_Undefer_Direct
), Loc
));
215 Make_Block_Statement
(Loc
,
216 Handled_Statement_Sequence
=> HSS
));
218 Set_Scope
(Blk
, Current_Scope
);
219 Set_Etype
(Blk
, Standard_Void_Type
);
220 Set_Identifier
(N
, New_Occurrence_Of
(Blk
, Sloc
(N
)));
221 Expand_At_End_Handler
(HSS
, Blk
);
223 end Expand_Pragma_Abort_Defer
;
225 --------------------------
226 -- Expand_Pragma_Assert --
227 --------------------------
229 procedure Expand_Pragma_Assert
(N
: Node_Id
) is
230 Loc
: constant Source_Ptr
:= Sloc
(N
);
231 Cond
: constant Node_Id
:= Arg1
(N
);
235 -- We already know that assertions are enabled, because otherwise
236 -- the semantic pass dealt with rewriting the assertion (see Sem_Prag)
238 pragma Assert
(Assertions_Enabled
);
240 -- Since assertions are on, we rewrite the pragma with its
241 -- corresponding if statement, and then analyze the statement
242 -- The expansion transforms:
244 -- pragma Assert (condition [,message]);
248 -- if not condition then
249 -- System.Assertions.Raise_Assert_Failure (Str);
252 -- where Str is the message if one is present, or the default of
253 -- file:line if no message is given.
255 -- First, we need to prepare the character literal
257 if Present
(Arg2
(N
)) then
258 Msg
:= Strval
(Expr_Value_S
(Arg2
(N
)));
260 Build_Location_String
(Loc
);
261 Msg
:= String_From_Name_Buffer
;
264 -- Now generate the if statement. Note that we consider this to be
265 -- an explicit conditional in the source, not an implicit if, so we
266 -- do not call Make_Implicit_If_Statement.
269 Make_If_Statement
(Loc
,
273 Then_Statements
=> New_List
(
274 Make_Procedure_Call_Statement
(Loc
,
276 New_Reference_To
(RTE
(RE_Raise_Assert_Failure
), Loc
),
277 Parameter_Associations
=> New_List
(
278 Make_String_Literal
(Loc
, Msg
))))));
282 -- If new condition is always false, give a warning
284 if Nkind
(N
) = N_Procedure_Call_Statement
285 and then Is_RTE
(Entity
(Name
(N
)), RE_Raise_Assert_Failure
)
287 -- If original condition was a Standard.False, we assume
288 -- that this is indeed intented to raise assert error
289 -- and no warning is required.
291 if Is_Entity_Name
(Original_Node
(Cond
))
292 and then Entity
(Original_Node
(Cond
)) = Standard_False
296 Error_Msg_N
("?assertion will fail at run-time", N
);
299 end Expand_Pragma_Assert
;
301 ---------------------------------
302 -- Expand_Pragma_Common_Object --
303 ---------------------------------
305 -- Use a machine attribute to replicate semantic effect in DEC Ada
307 -- pragma Machine_Attribute (intern_name, "common_object", extern_name);
309 -- For now we do nothing with the size attribute ???
311 procedure Expand_Pragma_Common_Object
(N
: Node_Id
) is
312 Loc
: constant Source_Ptr
:= Sloc
(N
);
314 Internal
: constant Node_Id
:= Arg1
(N
);
315 External
: constant Node_Id
:= Arg2
(N
);
318 -- Psect value upper cased as string literal
320 Iloc
: constant Source_Ptr
:= Sloc
(Internal
);
321 Eloc
: constant Source_Ptr
:= Sloc
(External
);
325 -- Acquire Psect value and fold to upper case
327 if Present
(External
) then
328 if Nkind
(External
) = N_String_Literal
then
329 String_To_Name_Buffer
(Strval
(External
));
331 Get_Name_String
(Chars
(External
));
337 Make_String_Literal
(Eloc
,
338 Strval
=> String_From_Name_Buffer
);
341 Get_Name_String
(Chars
(Internal
));
344 Make_String_Literal
(Iloc
,
345 Strval
=> String_From_Name_Buffer
);
348 Ploc
:= Sloc
(Psect
);
352 Insert_After_And_Analyze
(N
,
355 Chars
=> Name_Machine_Attribute
,
356 Pragma_Argument_Associations
=> New_List
(
357 Make_Pragma_Argument_Association
(Iloc
,
358 Expression
=> New_Copy_Tree
(Internal
)),
359 Make_Pragma_Argument_Association
(Eloc
,
361 Make_String_Literal
(Sloc
=> Ploc
,
362 Strval
=> "common_object")),
363 Make_Pragma_Argument_Association
(Ploc
,
364 Expression
=> New_Copy_Tree
(Psect
)))));
366 end Expand_Pragma_Common_Object
;
368 ---------------------------------------
369 -- Expand_Pragma_Import_Or_Interface --
370 ---------------------------------------
372 -- When applied to a variable, the default initialization must not be
373 -- done. As it is already done when the pragma is found, we just get rid
374 -- of the call the initialization procedure which followed the object
375 -- declaration. The call is inserted after the declaration, but validity
376 -- checks may also have been inserted and the initialization call does
377 -- not necessarily appear immediately after the object declaration.
379 -- We can't use the freezing mechanism for this purpose, since we
380 -- have to elaborate the initialization expression when it is first
381 -- seen (i.e. this elaboration cannot be deferred to the freeze point).
383 procedure Expand_Pragma_Import_Or_Interface
(N
: Node_Id
) is
384 Def_Id
: constant Entity_Id
:= Entity
(Arg2
(N
));
389 if Ekind
(Def_Id
) = E_Variable
then
390 Typ
:= Etype
(Def_Id
);
394 Init_Call
:= Next
(Parent
(Def_Id
));
395 while Present
(Init_Call
) and then Init_Call
/= N
loop
396 if Has_Non_Null_Base_Init_Proc
(Typ
)
397 and then Nkind
(Init_Call
) = N_Procedure_Call_Statement
398 and then Is_Entity_Name
(Name
(Init_Call
))
399 and then Entity
(Name
(Init_Call
)) = Base_Init_Proc
(Typ
)
408 -- Any default initialization expression should be removed
409 -- (e.g., null defaults for access objects, zero initialization
410 -- of packed bit arrays). Imported objects aren't allowed to
411 -- have explicit initialization, so the expression must have
412 -- been generated by the compiler.
415 and then Present
(Expression
(Parent
(Def_Id
)))
417 Set_Expression
(Parent
(Def_Id
), Empty
);
420 end Expand_Pragma_Import_Or_Interface
;
422 -------------------------------------------
423 -- Expand_Pragma_Import_Export_Exception --
424 -------------------------------------------
426 -- For a VMS exception fix up the language field with "VMS"
427 -- instead of "Ada" (gigi needs this), create a constant that will be the
428 -- value of the VMS condition code and stuff the Interface_Name field
429 -- with the unexpanded name of the exception (if not already set).
430 -- For a Ada exception, just stuff the Interface_Name field
431 -- with the unexpanded name of the exception (if not already set).
433 procedure Expand_Pragma_Import_Export_Exception
(N
: Node_Id
) is
435 -- This pragma is only effective on OpenVMS systems, it was ignored
436 -- on non-VMS systems, and we need to ignore it here as well.
438 if not OpenVMS_On_Target
then
443 Id
: constant Entity_Id
:= Entity
(Arg1
(N
));
444 Call
: constant Node_Id
:= Register_Exception_Call
(Id
);
445 Loc
: constant Source_Ptr
:= Sloc
(N
);
448 if Present
(Call
) then
450 Excep_Internal
: constant Node_Id
:=
451 Make_Defining_Identifier
452 (Loc
, New_Internal_Name
('V'));
453 Export_Pragma
: Node_Id
;
454 Excep_Alias
: Node_Id
;
455 Excep_Object
: Node_Id
;
456 Excep_Image
: String_Id
;
464 if Present
(Interface_Name
(Id
)) then
465 Excep_Image
:= Strval
(Interface_Name
(Id
));
467 Get_Name_String
(Chars
(Id
));
469 Excep_Image
:= String_From_Name_Buffer
;
472 Exdata
:= Component_Associations
(Expression
(Parent
(Id
)));
474 if Is_VMS_Exception
(Id
) then
475 Lang1
:= Next
(First
(Exdata
));
476 Lang2
:= Next
(Lang1
);
477 Lang3
:= Next
(Lang2
);
479 Rewrite
(Expression
(Lang1
),
480 Make_Character_Literal
(Loc
,
482 Char_Literal_Value
=>
483 UI_From_Int
(Character'Pos ('V'))));
484 Analyze
(Expression
(Lang1
));
486 Rewrite
(Expression
(Lang2
),
487 Make_Character_Literal
(Loc
,
489 Char_Literal_Value
=>
490 UI_From_Int
(Character'Pos ('M'))));
491 Analyze
(Expression
(Lang2
));
493 Rewrite
(Expression
(Lang3
),
494 Make_Character_Literal
(Loc
,
496 Char_Literal_Value
=>
497 UI_From_Int
(Character'Pos ('S'))));
498 Analyze
(Expression
(Lang3
));
500 if Exception_Code
(Id
) /= No_Uint
then
502 Make_Integer_Literal
(Loc
,
503 Intval
=> Exception_Code
(Id
));
506 Make_Object_Declaration
(Loc
,
507 Defining_Identifier
=> Excep_Internal
,
509 New_Reference_To
(RTE
(RE_Exception_Code
), Loc
));
511 Insert_Action
(N
, Excep_Object
);
512 Analyze
(Excep_Object
);
516 (UI_To_Int
(Exception_Code
(Id
)) / 8 * 8);
523 (Make_Pragma_Argument_Association
526 New_Reference_To
(Excep_Internal
, Loc
)),
528 Make_Pragma_Argument_Association
533 Strval
=> End_String
))));
535 Insert_Action
(N
, Excep_Alias
);
536 Analyze
(Excep_Alias
);
543 (Make_Pragma_Argument_Association
545 Expression
=> Make_Identifier
(Loc
, Name_C
)),
547 Make_Pragma_Argument_Association
550 New_Reference_To
(Excep_Internal
, Loc
)),
552 Make_Pragma_Argument_Association
557 Strval
=> Excep_Image
)),
559 Make_Pragma_Argument_Association
564 Strval
=> Excep_Image
))));
566 Insert_Action
(N
, Export_Pragma
);
567 Analyze
(Export_Pragma
);
571 Unchecked_Convert_To
(RTE
(RE_Exception_Code
),
572 Make_Function_Call
(Loc
,
574 New_Reference_To
(RTE
(RE_Import_Value
), Loc
),
575 Parameter_Associations
=> New_List
576 (Make_String_Literal
(Loc
,
577 Strval
=> Excep_Image
))));
581 Make_Procedure_Call_Statement
(Loc
,
582 Name
=> New_Reference_To
583 (RTE
(RE_Register_VMS_Exception
), Loc
),
584 Parameter_Associations
=> New_List
(
586 Unchecked_Convert_To
(RTE
(RE_Exception_Data_Ptr
),
587 Make_Attribute_Reference
(Loc
,
588 Prefix
=> New_Occurrence_Of
(Id
, Loc
),
589 Attribute_Name
=> Name_Unrestricted_Access
)))));
591 Analyze_And_Resolve
(Code
, RTE
(RE_Exception_Code
));
595 if No
(Interface_Name
(Id
)) then
596 Set_Interface_Name
(Id
,
599 Strval
=> Excep_Image
));
604 end Expand_Pragma_Import_Export_Exception
;
606 ------------------------------------
607 -- Expand_Pragma_Inspection_Point --
608 ------------------------------------
610 -- If no argument is given, then we supply a default argument list that
611 -- includes all objects declared at the source level in all subprograms
612 -- that enclose the inspection point pragma.
614 procedure Expand_Pragma_Inspection_Point
(N
: Node_Id
) is
615 Loc
: constant Source_Ptr
:= Sloc
(N
);
622 if No
(Pragma_Argument_Associations
(N
)) then
626 while S
/= Standard_Standard
loop
627 E
:= First_Entity
(S
);
628 while Present
(E
) loop
629 if Comes_From_Source
(E
)
630 and then Is_Object
(E
)
631 and then not Is_Entry_Formal
(E
)
632 and then Ekind
(E
) /= E_Component
633 and then Ekind
(E
) /= E_Discriminant
634 and then Ekind
(E
) /= E_Generic_In_Parameter
635 and then Ekind
(E
) /= E_Generic_In_Out_Parameter
638 Make_Pragma_Argument_Association
(Loc
,
639 Expression
=> New_Occurrence_Of
(E
, Loc
)));
648 Set_Pragma_Argument_Associations
(N
, A
);
651 -- Expand the arguments of the pragma. Expanding an entity reference
652 -- is a noop, except in a protected operation, where a reference may
653 -- have to be transformed into a reference to the corresponding prival.
654 -- Are there other pragmas that may require this ???
656 Assoc
:= First
(Pragma_Argument_Associations
(N
));
658 while Present
(Assoc
) loop
659 Expand
(Expression
(Assoc
));
662 end Expand_Pragma_Inspection_Point
;
664 --------------------------------------
665 -- Expand_Pragma_Interrupt_Priority --
666 --------------------------------------
668 -- Supply default argument if none exists (System.Interrupt_Priority'Last)
670 procedure Expand_Pragma_Interrupt_Priority
(N
: Node_Id
) is
671 Loc
: constant Source_Ptr
:= Sloc
(N
);
674 if No
(Pragma_Argument_Associations
(N
)) then
675 Set_Pragma_Argument_Associations
(N
, New_List
(
676 Make_Pragma_Argument_Association
(Loc
,
678 Make_Attribute_Reference
(Loc
,
680 New_Occurrence_Of
(RTE
(RE_Interrupt_Priority
), Loc
),
681 Attribute_Name
=> Name_Last
))));
683 end Expand_Pragma_Interrupt_Priority
;
685 --------------------------------
686 -- Expand_Pragma_Psect_Object --
687 --------------------------------
689 -- Convert to Common_Object, and expand the resulting pragma
691 procedure Expand_Pragma_Psect_Object
(N
: Node_Id
) is
693 Set_Chars
(N
, Name_Common_Object
);
694 Expand_Pragma_Common_Object
(N
);
695 end Expand_Pragma_Psect_Object
;