1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2004 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, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, 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_Association
63 procedure Expand_Pragma_Abort_Defer
(N
: Node_Id
);
64 procedure Expand_Pragma_Assert
(N
: Node_Id
);
65 procedure Expand_Pragma_Import
(N
: Node_Id
);
66 procedure Expand_Pragma_Import_Export_Exception
(N
: Node_Id
);
67 procedure Expand_Pragma_Inspection_Point
(N
: Node_Id
);
68 procedure Expand_Pragma_Interrupt_Priority
(N
: Node_Id
);
74 function Arg1
(N
: Node_Id
) return Node_Id
is
76 return First
(Pragma_Argument_Associations
(N
));
83 function Arg2
(N
: Node_Id
) return Node_Id
is
85 return Next
(Arg1
(N
));
92 procedure Expand_N_Pragma
(N
: Node_Id
) is
94 -- Note: we may have a pragma whose chars field is not a
95 -- recognized pragma, and we must ignore it at this stage.
97 if Is_Pragma_Name
(Chars
(N
)) then
98 case Get_Pragma_Id
(Chars
(N
)) is
100 -- Pragmas requiring special expander action
102 when Pragma_Abort_Defer
=>
103 Expand_Pragma_Abort_Defer
(N
);
105 when Pragma_Assert
=>
106 Expand_Pragma_Assert
(N
);
108 when Pragma_Export_Exception
=>
109 Expand_Pragma_Import_Export_Exception
(N
);
111 when Pragma_Import
=>
112 Expand_Pragma_Import
(N
);
114 when Pragma_Import_Exception
=>
115 Expand_Pragma_Import_Export_Exception
(N
);
117 when Pragma_Inspection_Point
=>
118 Expand_Pragma_Inspection_Point
(N
);
120 when Pragma_Interrupt_Priority
=>
121 Expand_Pragma_Interrupt_Priority
(N
);
123 -- All other pragmas need no expander action
131 -------------------------------
132 -- Expand_Pragma_Abort_Defer --
133 -------------------------------
135 -- An Abort_Defer pragma appears as the first statement in a handled
136 -- statement sequence (right after the begin). It defers aborts for
137 -- the entire statement sequence, but not for any declarations or
138 -- handlers (if any) associated with this statement sequence.
140 -- The transformation is to transform
142 -- pragma Abort_Defer;
151 -- when all others =>
152 -- Abort_Undefer.all;
155 -- Abort_Undefer_Direct;
158 procedure Expand_Pragma_Abort_Defer
(N
: Node_Id
) is
159 Loc
: constant Source_Ptr
:= Sloc
(N
);
163 Blk
: constant Entity_Id
:=
164 New_Internal_Entity
(E_Block
, Current_Scope
, Sloc
(N
), 'B');
167 Stms
:= New_List
(Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
170 Stm
:= Remove_Next
(N
);
176 Make_Handled_Sequence_Of_Statements
(Loc
,
179 New_Occurrence_Of
(RTE
(RE_Abort_Undefer_Direct
), Loc
));
182 Make_Block_Statement
(Loc
,
183 Handled_Statement_Sequence
=> HSS
));
185 Set_Scope
(Blk
, Current_Scope
);
186 Set_Etype
(Blk
, Standard_Void_Type
);
187 Set_Identifier
(N
, New_Occurrence_Of
(Blk
, Sloc
(N
)));
188 Expand_At_End_Handler
(HSS
, Blk
);
190 end Expand_Pragma_Abort_Defer
;
192 --------------------------
193 -- Expand_Pragma_Assert --
194 --------------------------
196 procedure Expand_Pragma_Assert
(N
: Node_Id
) is
197 Loc
: constant Source_Ptr
:= Sloc
(N
);
198 Cond
: constant Node_Id
:= Expression
(Arg1
(N
));
202 -- We already know that assertions are enabled, because otherwise
203 -- the semantic pass dealt with rewriting the assertion (see Sem_Prag)
205 pragma Assert
(Assertions_Enabled
);
207 -- Since assertions are on, we rewrite the pragma with its
208 -- corresponding if statement, and then analyze the statement
209 -- The expansion transforms:
211 -- pragma Assert (condition [,message]);
215 -- if not condition then
216 -- System.Assertions.Raise_Assert_Failure (Str);
219 -- where Str is the message if one is present, or the default of
220 -- file:line if no message is given.
222 -- First, we need to prepare the character literal
224 if Present
(Arg2
(N
)) then
225 Msg
:= Strval
(Expr_Value_S
(Expression
(Arg2
(N
))));
227 Build_Location_String
(Loc
);
228 Msg
:= String_From_Name_Buffer
;
231 -- Now generate the if statement. Note that we consider this to be
232 -- an explicit conditional in the source, not an implicit if, so we
233 -- do not call Make_Implicit_If_Statement.
236 Make_If_Statement
(Loc
,
240 Then_Statements
=> New_List
(
241 Make_Procedure_Call_Statement
(Loc
,
243 New_Reference_To
(RTE
(RE_Raise_Assert_Failure
), Loc
),
244 Parameter_Associations
=> New_List
(
245 Make_String_Literal
(Loc
, Msg
))))));
249 -- If new condition is always false, give a warning
251 if Nkind
(N
) = N_Procedure_Call_Statement
252 and then Is_RTE
(Entity
(Name
(N
)), RE_Raise_Assert_Failure
)
254 -- If original condition was a Standard.False, we assume
255 -- that this is indeed intented to raise assert error
256 -- and no warning is required.
258 if Is_Entity_Name
(Original_Node
(Cond
))
259 and then Entity
(Original_Node
(Cond
)) = Standard_False
263 Error_Msg_N
("?assertion will fail at run-time", N
);
266 end Expand_Pragma_Assert
;
268 --------------------------
269 -- Expand_Pragma_Import --
270 --------------------------
272 -- When applied to a variable, the default initialization must not be
273 -- done. As it is already done when the pragma is found, we just get rid
274 -- of the call the initialization procedure which followed the object
275 -- declaration. The call is inserted after the declaration, but validity
276 -- checks may also have been inserted and the initialization call does
277 -- not necessarily appear immediately after the object declaration.
279 -- We can't use the freezing mechanism for this purpose, since we
280 -- have to elaborate the initialization expression when it is first
281 -- seen (i.e. this elaboration cannot be deferred to the freeze point).
283 procedure Expand_Pragma_Import
(N
: Node_Id
) is
284 Def_Id
: constant Entity_Id
:= Entity
(Expression
(Arg2
(N
)));
289 if Ekind
(Def_Id
) = E_Variable
then
290 Typ
:= Etype
(Def_Id
);
294 Init_Call
:= Next
(Parent
(Def_Id
));
295 while Present
(Init_Call
) and then Init_Call
/= N
loop
296 if Has_Non_Null_Base_Init_Proc
(Typ
)
297 and then Nkind
(Init_Call
) = N_Procedure_Call_Statement
298 and then Is_Entity_Name
(Name
(Init_Call
))
299 and then Entity
(Name
(Init_Call
)) = Base_Init_Proc
(Typ
)
308 -- Any default initialization expression should be removed
309 -- (e.g., null defaults for access objects, zero initialization
310 -- of packed bit arrays). Imported objects aren't allowed to
311 -- have explicit initialization, so the expression must have
312 -- been generated by the compiler.
315 and then Present
(Expression
(Parent
(Def_Id
)))
317 Set_Expression
(Parent
(Def_Id
), Empty
);
320 end Expand_Pragma_Import
;
322 -------------------------------------------
323 -- Expand_Pragma_Import_Export_Exception --
324 -------------------------------------------
326 -- For a VMS exception fix up the language field with "VMS"
327 -- instead of "Ada" (gigi needs this), create a constant that will be the
328 -- value of the VMS condition code and stuff the Interface_Name field
329 -- with the unexpanded name of the exception (if not already set).
330 -- For a Ada exception, just stuff the Interface_Name field
331 -- with the unexpanded name of the exception (if not already set).
333 procedure Expand_Pragma_Import_Export_Exception
(N
: Node_Id
) is
335 -- This pragma is only effective on OpenVMS systems, it was ignored
336 -- on non-VMS systems, and we need to ignore it here as well.
338 if not OpenVMS_On_Target
then
343 Id
: constant Entity_Id
:= Entity
(Expression
(Arg1
(N
)));
344 Call
: constant Node_Id
:= Register_Exception_Call
(Id
);
345 Loc
: constant Source_Ptr
:= Sloc
(N
);
348 if Present
(Call
) then
350 Excep_Internal
: constant Node_Id
:=
351 Make_Defining_Identifier
352 (Loc
, New_Internal_Name
('V'));
353 Export_Pragma
: Node_Id
;
354 Excep_Alias
: Node_Id
;
355 Excep_Object
: Node_Id
;
356 Excep_Image
: String_Id
;
364 if Present
(Interface_Name
(Id
)) then
365 Excep_Image
:= Strval
(Interface_Name
(Id
));
367 Get_Name_String
(Chars
(Id
));
369 Excep_Image
:= String_From_Name_Buffer
;
372 Exdata
:= Component_Associations
(Expression
(Parent
(Id
)));
374 if Is_VMS_Exception
(Id
) then
375 Lang1
:= Next
(First
(Exdata
));
376 Lang2
:= Next
(Lang1
);
377 Lang3
:= Next
(Lang2
);
379 Rewrite
(Expression
(Lang1
),
380 Make_Character_Literal
(Loc
,
382 Char_Literal_Value
=> Get_Char_Code
('V')));
383 Analyze
(Expression
(Lang1
));
385 Rewrite
(Expression
(Lang2
),
386 Make_Character_Literal
(Loc
,
388 Char_Literal_Value
=> Get_Char_Code
('M')));
389 Analyze
(Expression
(Lang2
));
391 Rewrite
(Expression
(Lang3
),
392 Make_Character_Literal
(Loc
,
394 Char_Literal_Value
=> Get_Char_Code
('S')));
395 Analyze
(Expression
(Lang3
));
397 if Exception_Code
(Id
) /= No_Uint
then
399 Make_Integer_Literal
(Loc
,
400 Intval
=> Exception_Code
(Id
));
403 Make_Object_Declaration
(Loc
,
404 Defining_Identifier
=> Excep_Internal
,
406 New_Reference_To
(RTE
(RE_Exception_Code
), Loc
));
408 Insert_Action
(N
, Excep_Object
);
409 Analyze
(Excep_Object
);
413 (UI_To_Int
(Exception_Code
(Id
)) / 8 * 8);
420 (Make_Pragma_Argument_Association
423 New_Reference_To
(Excep_Internal
, Loc
)),
425 Make_Pragma_Argument_Association
430 Strval
=> End_String
))));
432 Insert_Action
(N
, Excep_Alias
);
433 Analyze
(Excep_Alias
);
440 (Make_Pragma_Argument_Association
442 Expression
=> Make_Identifier
(Loc
, Name_C
)),
444 Make_Pragma_Argument_Association
447 New_Reference_To
(Excep_Internal
, Loc
)),
449 Make_Pragma_Argument_Association
454 Strval
=> Excep_Image
)),
456 Make_Pragma_Argument_Association
461 Strval
=> Excep_Image
))));
463 Insert_Action
(N
, Export_Pragma
);
464 Analyze
(Export_Pragma
);
468 Unchecked_Convert_To
(RTE
(RE_Exception_Code
),
469 Make_Function_Call
(Loc
,
471 New_Reference_To
(RTE
(RE_Import_Value
), Loc
),
472 Parameter_Associations
=> New_List
473 (Make_String_Literal
(Loc
,
474 Strval
=> Excep_Image
))));
478 Make_Procedure_Call_Statement
(Loc
,
479 Name
=> New_Reference_To
480 (RTE
(RE_Register_VMS_Exception
), Loc
),
481 Parameter_Associations
=> New_List
(
483 Unchecked_Convert_To
(RTE
(RE_Exception_Data_Ptr
),
484 Make_Attribute_Reference
(Loc
,
485 Prefix
=> New_Occurrence_Of
(Id
, Loc
),
486 Attribute_Name
=> Name_Unrestricted_Access
)))));
488 Analyze_And_Resolve
(Code
, RTE
(RE_Exception_Code
));
492 if not Present
(Interface_Name
(Id
)) then
493 Set_Interface_Name
(Id
,
496 Strval
=> Excep_Image
));
501 end Expand_Pragma_Import_Export_Exception
;
503 ------------------------------------
504 -- Expand_Pragma_Inspection_Point --
505 ------------------------------------
507 -- If no argument is given, then we supply a default argument list that
508 -- includes all objects declared at the source level in all subprograms
509 -- that enclose the inspection point pragma.
511 procedure Expand_Pragma_Inspection_Point
(N
: Node_Id
) is
512 Loc
: constant Source_Ptr
:= Sloc
(N
);
519 if No
(Pragma_Argument_Associations
(N
)) then
523 while S
/= Standard_Standard
loop
524 E
:= First_Entity
(S
);
525 while Present
(E
) loop
526 if Comes_From_Source
(E
)
527 and then Is_Object
(E
)
528 and then not Is_Entry_Formal
(E
)
529 and then Ekind
(E
) /= E_Component
530 and then Ekind
(E
) /= E_Discriminant
531 and then Ekind
(E
) /= E_Generic_In_Parameter
532 and then Ekind
(E
) /= E_Generic_In_Out_Parameter
535 Make_Pragma_Argument_Association
(Loc
,
536 Expression
=> New_Occurrence_Of
(E
, Loc
)));
545 Set_Pragma_Argument_Associations
(N
, A
);
548 -- Expand the arguments of the pragma. Expanding an entity reference
549 -- is a noop, except in a protected operation, where a reference may
550 -- have to be transformed into a reference to the corresponding prival.
551 -- Are there other pragmas that may require this ???
553 Assoc
:= First
(Pragma_Argument_Associations
(N
));
555 while Present
(Assoc
) loop
556 Expand
(Expression
(Assoc
));
559 end Expand_Pragma_Inspection_Point
;
561 --------------------------------------
562 -- Expand_Pragma_Interrupt_Priority --
563 --------------------------------------
565 -- Supply default argument if none exists (System.Interrupt_Priority'Last)
567 procedure Expand_Pragma_Interrupt_Priority
(N
: Node_Id
) is
568 Loc
: constant Source_Ptr
:= Sloc
(N
);
571 if No
(Pragma_Argument_Associations
(N
)) then
572 Set_Pragma_Argument_Associations
(N
, New_List
(
573 Make_Pragma_Argument_Association
(Loc
,
575 Make_Attribute_Reference
(Loc
,
577 New_Occurrence_Of
(RTE
(RE_Interrupt_Priority
), Loc
),
578 Attribute_Name
=> Name_Last
))));
580 end Expand_Pragma_Interrupt_Priority
;