1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2012, 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 Errout
; use Errout
;
31 with Exp_Atag
; use Exp_Atag
;
32 with Exp_Ch4
; use Exp_Ch4
;
33 with Exp_Ch7
; use Exp_Ch7
;
34 with Exp_Ch11
; use Exp_Ch11
;
35 with Exp_Code
; use Exp_Code
;
36 with Exp_Fixd
; use Exp_Fixd
;
37 with Exp_Util
; use Exp_Util
;
38 with Freeze
; use Freeze
;
39 with Namet
; use Namet
;
40 with Nmake
; use Nmake
;
41 with Nlists
; use Nlists
;
43 with Restrict
; use Restrict
;
44 with Rident
; use Rident
;
45 with Rtsfind
; use Rtsfind
;
47 with Sem_Aux
; use Sem_Aux
;
48 with Sem_Eval
; use Sem_Eval
;
49 with Sem_Res
; use Sem_Res
;
50 with Sem_Type
; use Sem_Type
;
51 with Sem_Util
; use Sem_Util
;
52 with Sinfo
; use Sinfo
;
53 with Sinput
; use Sinput
;
54 with Snames
; use Snames
;
55 with Stand
; use Stand
;
56 with Stringt
; use Stringt
;
57 with Targparm
; use Targparm
;
58 with Tbuild
; use Tbuild
;
59 with Uintp
; use Uintp
;
60 with Urealp
; use Urealp
;
62 package body Exp_Intr
is
64 -----------------------
65 -- Local Subprograms --
66 -----------------------
68 procedure Expand_Binary_Operator_Call
(N
: Node_Id
);
69 -- Expand a call to an intrinsic arithmetic operator when the operand
70 -- types or sizes are not identical.
72 procedure Expand_Is_Negative
(N
: Node_Id
);
73 -- Expand a call to the intrinsic Is_Negative function
75 procedure Expand_Dispatching_Constructor_Call
(N
: Node_Id
);
76 -- Expand a call to an instantiation of Generic_Dispatching_Constructor
77 -- into a dispatching call to the actual subprogram associated with the
78 -- Constructor formal subprogram, passing it the Parameters actual of
79 -- the call to the instantiation and dispatching based on call's Tag
82 procedure Expand_Exception_Call
(N
: Node_Id
; Ent
: RE_Id
);
83 -- Expand a call to Exception_Information/Message/Name. The first
84 -- parameter, N, is the node for the function call, and Ent is the
85 -- entity for the corresponding routine in the Ada.Exceptions package.
87 procedure Expand_Import_Call
(N
: Node_Id
);
88 -- Expand a call to Import_Address/Longest_Integer/Value. The parameter
89 -- N is the node for the function call.
91 procedure Expand_Shift
(N
: Node_Id
; E
: Entity_Id
; K
: Node_Kind
);
92 -- Expand an intrinsic shift operation, N and E are from the call to
93 -- Expand_Intrinsic_Call (call node and subprogram spec entity) and
94 -- K is the kind for the shift node
96 procedure Expand_Unc_Conversion
(N
: Node_Id
; E
: Entity_Id
);
97 -- Expand a call to an instantiation of Unchecked_Conversion into a node
98 -- N_Unchecked_Type_Conversion.
100 procedure Expand_Unc_Deallocation
(N
: Node_Id
);
101 -- Expand a call to an instantiation of Unchecked_Deallocation into a node
102 -- N_Free_Statement and appropriate context.
104 procedure Expand_To_Address
(N
: Node_Id
);
105 procedure Expand_To_Pointer
(N
: Node_Id
);
106 -- Expand a call to corresponding function, declared in an instance of
107 -- System.Address_To_Access_Conversions.
109 procedure Expand_Source_Info
(N
: Node_Id
; Nam
: Name_Id
);
110 -- Rewrite the node by the appropriate string or positive constant.
111 -- Nam can be one of the following:
112 -- Name_File - expand string that is the name of source file
113 -- Name_Line - expand integer line number
114 -- Name_Source_Location - expand string of form file:line
115 -- Name_Enclosing_Entity - expand string with name of enclosing entity
117 ---------------------------------
118 -- Expand_Binary_Operator_Call --
119 ---------------------------------
121 procedure Expand_Binary_Operator_Call
(N
: Node_Id
) is
122 T1
: constant Entity_Id
:= Underlying_Type
(Etype
(Left_Opnd
(N
)));
123 T2
: constant Entity_Id
:= Underlying_Type
(Etype
(Right_Opnd
(N
)));
124 TR
: constant Entity_Id
:= Etype
(N
);
128 Siz
: constant Uint
:= UI_Max
(RM_Size
(T1
), RM_Size
(T2
));
129 -- Maximum of operand sizes
132 -- Nothing to do if the operands have the same modular type
134 if Base_Type
(T1
) = Base_Type
(T2
)
135 and then Is_Modular_Integer_Type
(T1
)
140 -- Use Unsigned_32 for sizes of 32 or below, else Unsigned_64
143 T3
:= RTE
(RE_Unsigned_64
);
145 T3
:= RTE
(RE_Unsigned_32
);
148 -- Copy operator node, and reset type and entity fields, for
149 -- subsequent reanalysis.
156 Set_Entity
(Res
, Standard_Op_And
);
158 Set_Entity
(Res
, Standard_Op_Or
);
160 Set_Entity
(Res
, Standard_Op_Xor
);
165 -- Convert operands to large enough intermediate type
168 Unchecked_Convert_To
(T3
, Relocate_Node
(Left_Opnd
(N
))));
170 Unchecked_Convert_To
(T3
, Relocate_Node
(Right_Opnd
(N
))));
172 -- Analyze and resolve result formed by conversion to target type
174 Rewrite
(N
, Unchecked_Convert_To
(TR
, Res
));
175 Analyze_And_Resolve
(N
, TR
);
176 end Expand_Binary_Operator_Call
;
178 -----------------------------------------
179 -- Expand_Dispatching_Constructor_Call --
180 -----------------------------------------
182 -- Transform a call to an instantiation of Generic_Dispatching_Constructor
185 -- GDC_Instance (The_Tag, Parameters'Access)
187 -- to a class-wide conversion of a dispatching call to the actual
188 -- associated with the formal subprogram Construct, designating The_Tag
189 -- as the controlling tag of the call:
191 -- T'Class (Construct'Actual (Params)) -- Controlling tag is The_Tag
193 -- which will eventually be expanded to the following:
195 -- T'Class (The_Tag.all (Construct'Actual'Index).all (Params))
197 -- A class-wide membership test is also generated, preceding the call, to
198 -- ensure that the controlling tag denotes a type in T'Class.
200 procedure Expand_Dispatching_Constructor_Call
(N
: Node_Id
) is
201 Loc
: constant Source_Ptr
:= Sloc
(N
);
202 Tag_Arg
: constant Node_Id
:= First_Actual
(N
);
203 Param_Arg
: constant Node_Id
:= Next_Actual
(Tag_Arg
);
204 Subp_Decl
: constant Node_Id
:= Parent
(Parent
(Entity
(Name
(N
))));
205 Inst_Pkg
: constant Node_Id
:= Parent
(Subp_Decl
);
206 Act_Rename
: Node_Id
;
207 Act_Constr
: Entity_Id
;
208 Iface_Tag
: Node_Id
:= Empty
;
209 Cnstr_Call
: Node_Id
;
210 Result_Typ
: Entity_Id
;
213 -- The subprogram is the third actual in the instantiation, and is
214 -- retrieved from the corresponding renaming declaration. However,
215 -- freeze nodes may appear before, so we retrieve the declaration
216 -- with an explicit loop.
218 Act_Rename
:= First
(Visible_Declarations
(Inst_Pkg
));
219 while Nkind
(Act_Rename
) /= N_Subprogram_Renaming_Declaration
loop
223 Act_Constr
:= Entity
(Name
(Act_Rename
));
224 Result_Typ
:= Class_Wide_Type
(Etype
(Act_Constr
));
226 -- Ada 2005 (AI-251): If the result is an interface type, the function
227 -- returns a class-wide interface type (otherwise the resulting object
228 -- would be abstract!)
230 if Is_Interface
(Etype
(Act_Constr
)) then
231 Set_Etype
(Act_Constr
, Result_Typ
);
233 -- If the result type is not parent of Tag_Arg then we need to
234 -- locate the tag of the secondary dispatch table.
236 if not Is_Ancestor
(Etype
(Result_Typ
), Etype
(Tag_Arg
),
237 Use_Full_View
=> True)
238 and then Tagged_Type_Expansion
240 -- Obtain the reference to the Ada.Tags service before generating
241 -- the Object_Declaration node to ensure that if this service is
242 -- not available in the runtime then we generate a clear error.
245 Fname
: constant Node_Id
:=
246 New_Reference_To
(RTE
(RE_Secondary_Tag
), Loc
);
249 pragma Assert
(not Is_Interface
(Etype
(Tag_Arg
)));
252 Make_Object_Declaration
(Loc
,
253 Defining_Identifier
=> Make_Temporary
(Loc
, 'V'),
255 New_Reference_To
(RTE
(RE_Tag
), Loc
),
257 Make_Function_Call
(Loc
,
259 Parameter_Associations
=> New_List
(
260 Relocate_Node
(Tag_Arg
),
262 (Node
(First_Elmt
(Access_Disp_Table
263 (Etype
(Etype
(Act_Constr
))))),
265 Insert_Action
(N
, Iface_Tag
);
270 -- Create the call to the actual Constructor function
273 Make_Function_Call
(Loc
,
274 Name
=> New_Occurrence_Of
(Act_Constr
, Loc
),
275 Parameter_Associations
=> New_List
(Relocate_Node
(Param_Arg
)));
277 -- Establish its controlling tag from the tag passed to the instance
278 -- The tag may be given by a function call, in which case a temporary
279 -- should be generated now, to prevent out-of-order insertions during
280 -- the expansion of that call when stack-checking is enabled.
282 if Present
(Iface_Tag
) then
283 Set_Controlling_Argument
(Cnstr_Call
,
284 New_Occurrence_Of
(Defining_Identifier
(Iface_Tag
), Loc
));
286 Remove_Side_Effects
(Tag_Arg
);
287 Set_Controlling_Argument
(Cnstr_Call
,
288 Relocate_Node
(Tag_Arg
));
291 -- Rewrite and analyze the call to the instance as a class-wide
292 -- conversion of the call to the actual constructor.
294 Rewrite
(N
, Convert_To
(Result_Typ
, Cnstr_Call
));
295 Analyze_And_Resolve
(N
, Etype
(Act_Constr
));
297 -- Do not generate a run-time check on the built object if tag
298 -- checks are suppressed for the result type or VM_Target /= No_VM
300 if Tag_Checks_Suppressed
(Etype
(Result_Typ
))
301 or else not Tagged_Type_Expansion
305 -- Generate a class-wide membership test to ensure that the call's tag
306 -- argument denotes a type within the class. We must keep separate the
307 -- case in which the Result_Type of the constructor function is a tagged
308 -- type from the case in which it is an abstract interface because the
309 -- run-time subprogram required to check these cases differ (and have
310 -- one difference in their parameters profile).
312 -- Call CW_Membership if the Result_Type is a tagged type to look for
313 -- the tag in the table of ancestor tags.
315 elsif not Is_Interface
(Result_Typ
) then
317 Obj_Tag_Node
: Node_Id
:= Duplicate_Subexpr
(Tag_Arg
);
318 CW_Test_Node
: Node_Id
;
321 Build_CW_Membership
(Loc
,
322 Obj_Tag_Node
=> Obj_Tag_Node
,
325 Node
(First_Elmt
(Access_Disp_Table
(
326 Root_Type
(Result_Typ
)))), Loc
),
328 New_Node
=> CW_Test_Node
);
331 Make_Implicit_If_Statement
(N
,
333 Make_Op_Not
(Loc
, CW_Test_Node
),
335 New_List
(Make_Raise_Statement
(Loc
,
336 New_Occurrence_Of
(RTE
(RE_Tag_Error
), Loc
)))));
339 -- Call IW_Membership test if the Result_Type is an abstract interface
340 -- to look for the tag in the table of interface tags.
344 Make_Implicit_If_Statement
(N
,
347 Make_Function_Call
(Loc
,
348 Name
=> New_Occurrence_Of
(RTE
(RE_IW_Membership
), Loc
),
349 Parameter_Associations
=> New_List
(
350 Make_Attribute_Reference
(Loc
,
351 Prefix
=> Duplicate_Subexpr
(Tag_Arg
),
352 Attribute_Name
=> Name_Address
),
355 Node
(First_Elmt
(Access_Disp_Table
(
356 Root_Type
(Result_Typ
)))), Loc
)))),
359 Make_Raise_Statement
(Loc
,
360 Name
=> New_Occurrence_Of
(RTE
(RE_Tag_Error
), Loc
)))));
362 end Expand_Dispatching_Constructor_Call
;
364 ---------------------------
365 -- Expand_Exception_Call --
366 ---------------------------
368 -- If the function call is not within an exception handler, then the call
369 -- is replaced by a null string. Otherwise the appropriate routine in
370 -- Ada.Exceptions is called passing the choice parameter specification
371 -- from the enclosing handler. If the enclosing handler lacks a choice
372 -- parameter, then one is supplied.
374 procedure Expand_Exception_Call
(N
: Node_Id
; Ent
: RE_Id
) is
375 Loc
: constant Source_Ptr
:= Sloc
(N
);
380 -- Climb up parents to see if we are in exception handler
384 -- Case of not in exception handler, replace by null string
388 Make_String_Literal
(Loc
,
392 -- Case of in exception handler
394 elsif Nkind
(P
) = N_Exception_Handler
then
396 -- Handler cannot be used for a local raise, and furthermore, this
397 -- is a violation of the No_Exception_Propagation restriction.
399 Set_Local_Raise_Not_OK
(P
);
400 Check_Restriction
(No_Exception_Propagation
, N
);
402 -- If no choice parameter present, then put one there. Note that
403 -- we do not need to put it on the entity chain, since no one will
404 -- be referencing it by normal visibility methods.
406 if No
(Choice_Parameter
(P
)) then
407 E
:= Make_Temporary
(Loc
, 'E');
408 Set_Choice_Parameter
(P
, E
);
409 Set_Ekind
(E
, E_Variable
);
410 Set_Etype
(E
, RTE
(RE_Exception_Occurrence
));
411 Set_Scope
(E
, Current_Scope
);
415 Make_Function_Call
(Loc
,
416 Name
=> New_Occurrence_Of
(RTE
(Ent
), Loc
),
417 Parameter_Associations
=> New_List
(
418 New_Occurrence_Of
(Choice_Parameter
(P
), Loc
))));
428 Analyze_And_Resolve
(N
, Standard_String
);
429 end Expand_Exception_Call
;
431 ------------------------
432 -- Expand_Import_Call --
433 ------------------------
435 -- The function call must have a static string as its argument. We create
436 -- a dummy variable which uses this string as the external name in an
437 -- Import pragma. The result is then obtained as the address of this
438 -- dummy variable, converted to the appropriate target type.
440 procedure Expand_Import_Call
(N
: Node_Id
) is
441 Loc
: constant Source_Ptr
:= Sloc
(N
);
442 Ent
: constant Entity_Id
:= Entity
(Name
(N
));
443 Str
: constant Node_Id
:= First_Actual
(N
);
444 Dum
: constant Entity_Id
:= Make_Temporary
(Loc
, 'D');
447 Insert_Actions
(N
, New_List
(
448 Make_Object_Declaration
(Loc
,
449 Defining_Identifier
=> Dum
,
451 New_Occurrence_Of
(Standard_Character
, Loc
)),
454 Chars
=> Name_Import
,
455 Pragma_Argument_Associations
=> New_List
(
456 Make_Pragma_Argument_Association
(Loc
,
457 Expression
=> Make_Identifier
(Loc
, Name_Ada
)),
459 Make_Pragma_Argument_Association
(Loc
,
460 Expression
=> Make_Identifier
(Loc
, Chars
(Dum
))),
462 Make_Pragma_Argument_Association
(Loc
,
463 Chars
=> Name_Link_Name
,
464 Expression
=> Relocate_Node
(Str
))))));
467 Unchecked_Convert_To
(Etype
(Ent
),
468 Make_Attribute_Reference
(Loc
,
469 Prefix
=> Make_Identifier
(Loc
, Chars
(Dum
)),
470 Attribute_Name
=> Name_Address
)));
472 Analyze_And_Resolve
(N
, Etype
(Ent
));
473 end Expand_Import_Call
;
475 ---------------------------
476 -- Expand_Intrinsic_Call --
477 ---------------------------
479 procedure Expand_Intrinsic_Call
(N
: Node_Id
; E
: Entity_Id
) is
483 -- If an external name is specified for the intrinsic, it is handled
484 -- by the back-end: leave the call node unchanged for now.
486 if Present
(Interface_Name
(E
)) then
490 -- If the intrinsic subprogram is generic, gets its original name
492 if Present
(Parent
(E
))
493 and then Present
(Generic_Parent
(Parent
(E
)))
495 Nam
:= Chars
(Generic_Parent
(Parent
(E
)));
500 if Nam
= Name_Asm
then
503 elsif Nam
= Name_Divide
then
504 Expand_Decimal_Divide_Call
(N
);
506 elsif Nam
= Name_Exception_Information
then
507 Expand_Exception_Call
(N
, RE_Exception_Information
);
509 elsif Nam
= Name_Exception_Message
then
510 Expand_Exception_Call
(N
, RE_Exception_Message
);
512 elsif Nam
= Name_Exception_Name
then
513 Expand_Exception_Call
(N
, RE_Exception_Name_Simple
);
515 elsif Nam
= Name_Generic_Dispatching_Constructor
then
516 Expand_Dispatching_Constructor_Call
(N
);
518 elsif Nam
= Name_Import_Address
520 Nam
= Name_Import_Largest_Value
522 Nam
= Name_Import_Value
524 Expand_Import_Call
(N
);
526 elsif Nam
= Name_Is_Negative
then
527 Expand_Is_Negative
(N
);
529 elsif Nam
= Name_Rotate_Left
then
530 Expand_Shift
(N
, E
, N_Op_Rotate_Left
);
532 elsif Nam
= Name_Rotate_Right
then
533 Expand_Shift
(N
, E
, N_Op_Rotate_Right
);
535 elsif Nam
= Name_Shift_Left
then
536 Expand_Shift
(N
, E
, N_Op_Shift_Left
);
538 elsif Nam
= Name_Shift_Right
then
539 Expand_Shift
(N
, E
, N_Op_Shift_Right
);
541 elsif Nam
= Name_Shift_Right_Arithmetic
then
542 Expand_Shift
(N
, E
, N_Op_Shift_Right_Arithmetic
);
544 elsif Nam
= Name_Unchecked_Conversion
then
545 Expand_Unc_Conversion
(N
, E
);
547 elsif Nam
= Name_Unchecked_Deallocation
then
548 Expand_Unc_Deallocation
(N
);
550 elsif Nam
= Name_To_Address
then
551 Expand_To_Address
(N
);
553 elsif Nam
= Name_To_Pointer
then
554 Expand_To_Pointer
(N
);
556 elsif Nam
= Name_File
557 or else Nam
= Name_Line
558 or else Nam
= Name_Source_Location
559 or else Nam
= Name_Enclosing_Entity
561 Expand_Source_Info
(N
, Nam
);
563 -- If we have a renaming, expand the call to the original operation,
564 -- which must itself be intrinsic, since renaming requires matching
565 -- conventions and this has already been checked.
567 elsif Present
(Alias
(E
)) then
568 Expand_Intrinsic_Call
(N
, Alias
(E
));
570 elsif Nkind
(N
) in N_Binary_Op
then
571 Expand_Binary_Operator_Call
(N
);
573 -- The only other case is where an external name was specified, since
574 -- this is the only way that an otherwise unrecognized name could
575 -- escape the checking in Sem_Prag. Nothing needs to be done in such
576 -- a case, since we pass such a call to the back end unchanged.
581 end Expand_Intrinsic_Call
;
583 ------------------------
584 -- Expand_Is_Negative --
585 ------------------------
587 procedure Expand_Is_Negative
(N
: Node_Id
) is
588 Loc
: constant Source_Ptr
:= Sloc
(N
);
589 Opnd
: constant Node_Id
:= Relocate_Node
(First_Actual
(N
));
593 -- We replace the function call by the following expression
595 -- if Opnd < 0.0 then
598 -- if Opnd > 0.0 then
601 -- Float_Unsigned!(Float (Opnd)) /= 0
606 Make_If_Expression
(Loc
,
607 Expressions
=> New_List
(
609 Left_Opnd
=> Duplicate_Subexpr
(Opnd
),
610 Right_Opnd
=> Make_Real_Literal
(Loc
, Ureal_0
)),
612 New_Occurrence_Of
(Standard_True
, Loc
),
614 Make_If_Expression
(Loc
,
615 Expressions
=> New_List
(
617 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Opnd
),
618 Right_Opnd
=> Make_Real_Literal
(Loc
, Ureal_0
)),
620 New_Occurrence_Of
(Standard_False
, Loc
),
625 (RTE
(RE_Float_Unsigned
),
628 Duplicate_Subexpr_No_Checks
(Opnd
))),
630 Make_Integer_Literal
(Loc
, 0)))))));
632 Analyze_And_Resolve
(N
, Standard_Boolean
);
633 end Expand_Is_Negative
;
639 -- This procedure is used to convert a call to a shift function to the
640 -- corresponding operator node. This conversion is not done by the usual
641 -- circuit for converting calls to operator functions (e.g. "+"(1,2)) to
642 -- operator nodes, because shifts are not predefined operators.
644 -- As a result, whenever a shift is used in the source program, it will
645 -- remain as a call until converted by this routine to the operator node
646 -- form which Gigi is expecting to see.
648 -- Note: it is possible for the expander to generate shift operator nodes
649 -- directly, which will be analyzed in the normal manner by calling Analyze
650 -- and Resolve. Such shift operator nodes will not be seen by Expand_Shift.
652 procedure Expand_Shift
(N
: Node_Id
; E
: Entity_Id
; K
: Node_Kind
) is
653 Entyp
: constant Entity_Id
:= Etype
(E
);
654 Left
: constant Node_Id
:= First_Actual
(N
);
655 Loc
: constant Source_Ptr
:= Sloc
(N
);
656 Right
: constant Node_Id
:= Next_Actual
(Left
);
657 Ltyp
: constant Node_Id
:= Etype
(Left
);
658 Rtyp
: constant Node_Id
:= Etype
(Right
);
659 Typ
: constant Entity_Id
:= Etype
(N
);
663 Snode
:= New_Node
(K
, Loc
);
664 Set_Right_Opnd
(Snode
, Relocate_Node
(Right
));
665 Set_Chars
(Snode
, Chars
(E
));
666 Set_Etype
(Snode
, Base_Type
(Entyp
));
667 Set_Entity
(Snode
, E
);
669 if Compile_Time_Known_Value
(Type_High_Bound
(Rtyp
))
670 and then Expr_Value
(Type_High_Bound
(Rtyp
)) < Esize
(Ltyp
)
672 Set_Shift_Count_OK
(Snode
, True);
677 -- Note that we don't call Analyze and Resolve on this node, because
678 -- it already got analyzed and resolved when it was a function call.
680 Set_Left_Opnd
(Snode
, Relocate_Node
(Left
));
686 -- If the context type is not the type of the operator, it is an
687 -- inherited operator for a derived type. Wrap the node in a
688 -- conversion so that it is type-consistent for possible further
689 -- expansion (e.g. within a lock-free protected type).
691 Set_Left_Opnd
(Snode
,
692 Unchecked_Convert_To
(Base_Type
(Entyp
), Relocate_Node
(Left
)));
693 Rewrite
(N
, Unchecked_Convert_To
(Typ
, Snode
));
695 -- Analyze and resolve result formed by conversion to target type
697 Analyze_And_Resolve
(N
, Typ
);
701 ------------------------
702 -- Expand_Source_Info --
703 ------------------------
705 procedure Expand_Source_Info
(N
: Node_Id
; Nam
: Name_Id
) is
706 Loc
: constant Source_Ptr
:= Sloc
(N
);
709 procedure Write_Entity_Name
(E
: Entity_Id
);
710 -- Recursive procedure to construct string for qualified name of
711 -- enclosing program unit. The qualification stops at an enclosing
712 -- scope has no source name (block or loop). If entity is a subprogram
713 -- instance, skip enclosing wrapper package.
715 -----------------------
716 -- Write_Entity_Name --
717 -----------------------
719 procedure Write_Entity_Name
(E
: Entity_Id
) is
721 TDef
: constant Source_Buffer_Ptr
:=
722 Source_Text
(Get_Source_File_Index
(Sloc
(E
)));
725 -- Nothing to do if at outer level
727 if Scope
(E
) = Standard_Standard
then
730 -- If scope comes from source, write its name
732 elsif Comes_From_Source
(Scope
(E
)) then
733 Write_Entity_Name
(Scope
(E
));
734 Add_Char_To_Name_Buffer
('.');
736 -- If in wrapper package skip past it
738 elsif Is_Wrapper_Package
(Scope
(E
)) then
739 Write_Entity_Name
(Scope
(Scope
(E
)));
740 Add_Char_To_Name_Buffer
('.');
742 -- Otherwise nothing to output (happens in unnamed block statements)
748 -- Loop to output the name
750 -- is this right wrt wide char encodings ??? (no!)
753 while TDef
(SDef
) in '0' .. '9'
754 or else TDef
(SDef
) >= 'A'
755 or else TDef
(SDef
) = ASCII
.ESC
757 Add_Char_To_Name_Buffer
(TDef
(SDef
));
760 end Write_Entity_Name
;
762 -- Start of processing for Expand_Source_Info
767 if Nam
= Name_Line
then
769 Make_Integer_Literal
(Loc
,
770 Intval
=> UI_From_Int
(Int
(Get_Logical_Line_Number
(Loc
)))));
771 Analyze_And_Resolve
(N
, Standard_Positive
);
780 Get_Decoded_Name_String
781 (Reference_Name
(Get_Source_File_Index
(Loc
)));
783 when Name_Source_Location
=>
784 Build_Location_String
(Loc
);
786 when Name_Enclosing_Entity
=>
788 -- Skip enclosing blocks to reach enclosing unit
790 Ent
:= Current_Scope
;
791 while Present
(Ent
) loop
792 exit when Ekind
(Ent
) /= E_Block
793 and then Ekind
(Ent
) /= E_Loop
;
797 -- Ent now points to the relevant defining entity
799 Write_Entity_Name
(Ent
);
806 Make_String_Literal
(Loc
,
807 Strval
=> String_From_Name_Buffer
));
808 Analyze_And_Resolve
(N
, Standard_String
);
811 Set_Is_Static_Expression
(N
);
812 end Expand_Source_Info
;
814 ---------------------------
815 -- Expand_Unc_Conversion --
816 ---------------------------
818 procedure Expand_Unc_Conversion
(N
: Node_Id
; E
: Entity_Id
) is
819 Func
: constant Entity_Id
:= Entity
(Name
(N
));
825 -- Rewrite as unchecked conversion node. Note that we must convert
826 -- the operand to the formal type of the input parameter of the
827 -- function, so that the resulting N_Unchecked_Type_Conversion
828 -- call indicates the correct types for Gigi.
830 -- Right now, we only do this if a scalar type is involved. It is
831 -- not clear if it is needed in other cases. If we do attempt to
832 -- do the conversion unconditionally, it crashes 3411-018. To be
833 -- investigated further ???
835 Conv
:= Relocate_Node
(First_Actual
(N
));
836 Ftyp
:= Etype
(First_Formal
(Func
));
838 if Is_Scalar_Type
(Ftyp
) then
839 Conv
:= Convert_To
(Ftyp
, Conv
);
840 Set_Parent
(Conv
, N
);
841 Analyze_And_Resolve
(Conv
);
844 -- The instantiation of Unchecked_Conversion creates a wrapper package,
845 -- and the target type is declared as a subtype of the actual. Recover
846 -- the actual, which is the subtype indic. in the subtype declaration
847 -- for the target type. This is semantically correct, and avoids
848 -- anomalies with access subtypes. For entities, leave type as is.
850 -- We do the analysis here, because we do not want the compiler
851 -- to try to optimize or otherwise reorganize the unchecked
856 if Is_Entity_Name
(Conv
) then
859 elsif Nkind
(Parent
(Ttyp
)) = N_Subtype_Declaration
then
860 Ttyp
:= Entity
(Subtype_Indication
(Parent
(Etype
(E
))));
862 elsif Is_Itype
(Ttyp
) then
864 Entity
(Subtype_Indication
(Associated_Node_For_Itype
(Ttyp
)));
869 Rewrite
(N
, Unchecked_Convert_To
(Ttyp
, Conv
));
873 if Nkind
(N
) = N_Unchecked_Type_Conversion
then
874 Expand_N_Unchecked_Type_Conversion
(N
);
876 end Expand_Unc_Conversion
;
878 -----------------------------
879 -- Expand_Unc_Deallocation --
880 -----------------------------
882 -- Generate the following Code :
884 -- if Arg /= null then
885 -- <Finalize_Call> (.., T'Class(Arg.all), ..); -- for controlled types
890 -- For a task, we also generate a call to Free_Task to ensure that the
891 -- task itself is freed if it is terminated, ditto for a simple protected
892 -- object, with a call to Finalize_Protection. For composite types that
893 -- have tasks or simple protected objects as components, we traverse the
894 -- structures to find and terminate those components.
896 procedure Expand_Unc_Deallocation
(N
: Node_Id
) is
897 Arg
: constant Node_Id
:= First_Actual
(N
);
898 Loc
: constant Source_Ptr
:= Sloc
(N
);
899 Typ
: constant Entity_Id
:= Etype
(Arg
);
900 Desig_T
: constant Entity_Id
:= Designated_Type
(Typ
);
901 Rtyp
: constant Entity_Id
:= Underlying_Type
(Root_Type
(Typ
));
902 Pool
: constant Entity_Id
:= Associated_Storage_Pool
(Rtyp
);
903 Stmts
: constant List_Id
:= New_List
;
904 Needs_Fin
: constant Boolean := Needs_Finalization
(Desig_T
);
906 Finalizer_Data
: Finalization_Exception_Data
;
908 Blk
: Node_Id
:= Empty
;
910 Final_Code
: List_Id
;
915 Arg_Known_Non_Null
: constant Boolean := Known_Non_Null
(N
);
916 -- This captures whether we know the argument to be non-null so that
917 -- we can avoid the test. The reason that we need to capture this is
918 -- that we analyze some generated statements before properly attaching
919 -- them to the tree, and that can disturb current value settings.
922 -- Nothing to do if we know the argument is null
924 if Known_Null
(N
) then
928 -- Processing for pointer to controlled type
932 Make_Explicit_Dereference
(Loc
,
933 Prefix
=> Duplicate_Subexpr_No_Checks
(Arg
));
935 -- If the type is tagged, then we must force dispatching on the
936 -- finalization call because the designated type may not be the
937 -- actual type of the object.
939 if Is_Tagged_Type
(Desig_T
)
940 and then not Is_Class_Wide_Type
(Desig_T
)
942 Deref
:= Unchecked_Convert_To
(Class_Wide_Type
(Desig_T
), Deref
);
944 elsif not Is_Tagged_Type
(Desig_T
) then
946 -- Set type of result, to force a conversion when needed (see
947 -- exp_ch7, Convert_View), given that Deep_Finalize may be
948 -- inherited from the parent type, and we need the type of the
949 -- expression to see whether the conversion is in fact needed.
951 Set_Etype
(Deref
, Desig_T
);
954 -- The finalization call is expanded wrapped in a block to catch any
955 -- possible exception. If an exception does occur, then Program_Error
956 -- must be raised following the freeing of the object and its removal
957 -- from the finalization collection's list. We set a flag to record
958 -- that an exception was raised, and save its occurrence for use in
962 -- Abort : constant Boolean :=
963 -- Exception_Occurrence (Get_Current_Excep.all.all) =
964 -- Standard'Abort_Signal'Identity;
966 -- Abort : constant Boolean := False; -- no abort
968 -- E : Exception_Occurrence;
969 -- Raised : Boolean := False;
972 -- [Deep_]Finalize (Obj);
976 -- Save_Occurrence (E, Get_Current_Excep.all.all);
979 Build_Object_Declarations
(Finalizer_Data
, Stmts
, Loc
);
981 Final_Code
:= New_List
(
982 Make_Block_Statement
(Loc
,
983 Handled_Statement_Sequence
=>
984 Make_Handled_Sequence_Of_Statements
(Loc
,
985 Statements
=> New_List
(
986 Make_Final_Call
(Obj_Ref
=> Deref
, Typ
=> Desig_T
)),
987 Exception_Handlers
=> New_List
(
988 Build_Exception_Handler
(Finalizer_Data
)))));
990 -- For .NET/JVM, detach the object from the containing finalization
991 -- collection before finalizing it.
993 if VM_Target
/= No_VM
and then Is_Controlled
(Desig_T
) then
994 Prepend_To
(Final_Code
,
995 Make_Detach_Call
(New_Copy_Tree
(Arg
)));
998 -- If aborts are allowed, then the finalization code must be
999 -- protected by an abort defer/undefer pair.
1001 if Abort_Allowed
then
1002 Prepend_To
(Final_Code
,
1003 Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
1006 Make_Block_Statement
(Loc
, Handled_Statement_Sequence
=>
1007 Make_Handled_Sequence_Of_Statements
(Loc
,
1008 Statements
=> Final_Code
,
1010 New_Occurrence_Of
(RTE
(RE_Abort_Undefer_Direct
), Loc
)));
1012 Append
(Blk
, Stmts
);
1014 Append_List_To
(Stmts
, Final_Code
);
1018 -- For a task type, call Free_Task before freeing the ATCB
1020 if Is_Task_Type
(Desig_T
) then
1022 Stat
: Node_Id
:= Prev
(N
);
1027 -- An Abort followed by a Free will not do what the user expects,
1028 -- because the abort is not immediate. This is worth a warning.
1030 while Present
(Stat
)
1031 and then not Comes_From_Source
(Original_Node
(Stat
))
1037 and then Nkind
(Original_Node
(Stat
)) = N_Abort_Statement
1039 Stat
:= Original_Node
(Stat
);
1040 Nam1
:= First
(Names
(Stat
));
1041 Nam2
:= Original_Node
(First
(Parameter_Associations
(N
)));
1043 if Nkind
(Nam1
) = N_Explicit_Dereference
1044 and then Is_Entity_Name
(Prefix
(Nam1
))
1045 and then Is_Entity_Name
(Nam2
)
1046 and then Entity
(Prefix
(Nam1
)) = Entity
(Nam2
)
1048 Error_Msg_N
("abort may take time to complete?", N
);
1049 Error_Msg_N
("\deallocation might have no effect?", N
);
1050 Error_Msg_N
("\safer to wait for termination.?", N
);
1056 (Stmts
, Cleanup_Task
(N
, Duplicate_Subexpr_No_Checks
(Arg
)));
1058 -- For composite types that contain tasks, recurse over the structure
1059 -- to build the selectors for the task subcomponents.
1061 elsif Has_Task
(Desig_T
) then
1062 if Is_Record_Type
(Desig_T
) then
1063 Append_List_To
(Stmts
, Cleanup_Record
(N
, Arg
, Desig_T
));
1065 elsif Is_Array_Type
(Desig_T
) then
1066 Append_List_To
(Stmts
, Cleanup_Array
(N
, Arg
, Desig_T
));
1070 -- Same for simple protected types. Eventually call Finalize_Protection
1071 -- before freeing the PO for each protected component.
1073 if Is_Simple_Protected_Type
(Desig_T
) then
1075 Cleanup_Protected_Object
(N
, Duplicate_Subexpr_No_Checks
(Arg
)));
1077 elsif Has_Simple_Protected_Object
(Desig_T
) then
1078 if Is_Record_Type
(Desig_T
) then
1079 Append_List_To
(Stmts
, Cleanup_Record
(N
, Arg
, Desig_T
));
1080 elsif Is_Array_Type
(Desig_T
) then
1081 Append_List_To
(Stmts
, Cleanup_Array
(N
, Arg
, Desig_T
));
1085 -- Normal processing for non-controlled types
1087 Free_Arg
:= Duplicate_Subexpr_No_Checks
(Arg
);
1088 Free_Node
:= Make_Free_Statement
(Loc
, Empty
);
1089 Append_To
(Stmts
, Free_Node
);
1090 Set_Storage_Pool
(Free_Node
, Pool
);
1092 -- Attach to tree before analysis of generated subtypes below
1094 Set_Parent
(Stmts
, Parent
(N
));
1096 -- Deal with storage pool
1098 if Present
(Pool
) then
1100 -- Freeing the secondary stack is meaningless
1102 if Is_RTE
(Pool
, RE_SS_Pool
) then
1105 -- If the pool object is of a simple storage pool type, then attempt
1106 -- to locate the type's Deallocate procedure, if any, and set the
1107 -- free operation's procedure to call. If the type doesn't have a
1108 -- Deallocate (which is allowed), then the actual will simply be set
1111 elsif Present
(Get_Rep_Pragma
1112 (Etype
(Pool
), Name_Simple_Storage_Pool_Type
))
1115 Pool_Type
: constant Entity_Id
:= Base_Type
(Etype
(Pool
));
1116 Dealloc_Op
: Entity_Id
;
1118 Dealloc_Op
:= Get_Name_Entity_Id
(Name_Deallocate
);
1119 while Present
(Dealloc_Op
) loop
1120 if Scope
(Dealloc_Op
) = Scope
(Pool_Type
)
1121 and then Present
(First_Formal
(Dealloc_Op
))
1122 and then Etype
(First_Formal
(Dealloc_Op
)) = Pool_Type
1124 Set_Procedure_To_Call
(Free_Node
, Dealloc_Op
);
1127 Dealloc_Op
:= Homonym
(Dealloc_Op
);
1132 -- Case of a class-wide pool type: make a dispatching call to
1133 -- Deallocate through the class-wide Deallocate_Any.
1135 elsif Is_Class_Wide_Type
(Etype
(Pool
)) then
1136 Set_Procedure_To_Call
(Free_Node
, RTE
(RE_Deallocate_Any
));
1138 -- Case of a specific pool type: make a statically bound call
1141 Set_Procedure_To_Call
(Free_Node
,
1142 Find_Prim_Op
(Etype
(Pool
), Name_Deallocate
));
1146 if Present
(Procedure_To_Call
(Free_Node
)) then
1148 -- For all cases of a Deallocate call, the back-end needs to be able
1149 -- to compute the size of the object being freed. This may require
1150 -- some adjustments for objects of dynamic size.
1152 -- If the type is class wide, we generate an implicit type with the
1153 -- right dynamic size, so that the deallocate call gets the right
1154 -- size parameter computed by GIGI. Same for an access to
1155 -- unconstrained packed array.
1157 if Is_Class_Wide_Type
(Desig_T
)
1159 (Is_Array_Type
(Desig_T
)
1160 and then not Is_Constrained
(Desig_T
)
1161 and then Is_Packed
(Desig_T
))
1164 Deref
: constant Node_Id
:=
1165 Make_Explicit_Dereference
(Loc
,
1166 Duplicate_Subexpr_No_Checks
(Arg
));
1171 -- Perform minor decoration as it is needed by the side effect
1172 -- removal mechanism.
1174 Set_Etype
(Deref
, Desig_T
);
1175 Set_Parent
(Deref
, Free_Node
);
1176 D_Subtyp
:= Make_Subtype_From_Expr
(Deref
, Desig_T
);
1178 if Nkind
(D_Subtyp
) in N_Has_Entity
then
1179 D_Type
:= Entity
(D_Subtyp
);
1182 D_Type
:= Make_Temporary
(Loc
, 'A');
1183 Insert_Action
(Deref
,
1184 Make_Subtype_Declaration
(Loc
,
1185 Defining_Identifier
=> D_Type
,
1186 Subtype_Indication
=> D_Subtyp
));
1189 -- Force freezing at the point of the dereference. For the
1190 -- class wide case, this avoids having the subtype frozen
1191 -- before the equivalent type.
1193 Freeze_Itype
(D_Type
, Deref
);
1195 Set_Actual_Designated_Subtype
(Free_Node
, D_Type
);
1201 -- Ada 2005 (AI-251): In case of abstract interface type we must
1202 -- displace the pointer to reference the base of the object to
1203 -- deallocate its memory, unless we're targetting a VM, in which case
1204 -- no special processing is required.
1207 -- free (Base_Address (Obj_Ptr))
1209 if Is_Interface
(Directly_Designated_Type
(Typ
))
1210 and then Tagged_Type_Expansion
1212 Set_Expression
(Free_Node
,
1213 Unchecked_Convert_To
(Typ
,
1214 Make_Function_Call
(Loc
,
1215 Name
=> New_Reference_To
(RTE
(RE_Base_Address
), Loc
),
1216 Parameter_Associations
=> New_List
(
1217 Unchecked_Convert_To
(RTE
(RE_Address
), Free_Arg
)))));
1223 Set_Expression
(Free_Node
, Free_Arg
);
1226 -- Only remaining step is to set result to null, or generate a raise of
1227 -- Constraint_Error if the target object is "not null".
1229 if Can_Never_Be_Null
(Etype
(Arg
)) then
1231 Make_Raise_Constraint_Error
(Loc
,
1232 Reason
=> CE_Access_Check_Failed
));
1236 Lhs
: constant Node_Id
:= Duplicate_Subexpr_No_Checks
(Arg
);
1238 Set_Assignment_OK
(Lhs
);
1240 Make_Assignment_Statement
(Loc
,
1242 Expression
=> Make_Null
(Loc
)));
1246 -- Generate a test of whether any earlier finalization raised an
1247 -- exception, and in that case raise Program_Error with the previous
1248 -- exception occurrence.
1251 -- if Raised and then not Abort then
1252 -- raise Program_Error; -- for .NET and
1253 -- -- restricted RTS
1255 -- Raise_From_Controlled_Operation (E); -- all other cases
1259 Append_To
(Stmts
, Build_Raise_Statement
(Finalizer_Data
));
1262 -- If we know the argument is non-null, then make a block statement
1263 -- that contains the required statements, no need for a test.
1265 if Arg_Known_Non_Null
then
1267 Make_Block_Statement
(Loc
,
1268 Handled_Statement_Sequence
=>
1269 Make_Handled_Sequence_Of_Statements
(Loc
,
1270 Statements
=> Stmts
));
1272 -- If the argument may be null, wrap the statements inside an IF that
1273 -- does an explicit test to exclude the null case.
1277 Make_Implicit_If_Statement
(N
,
1280 Left_Opnd
=> Duplicate_Subexpr
(Arg
),
1281 Right_Opnd
=> Make_Null
(Loc
)),
1282 Then_Statements
=> Stmts
);
1287 Rewrite
(N
, Gen_Code
);
1290 -- If we generated a block with an At_End_Proc, expand the exception
1291 -- handler. We need to wait until after everything else is analyzed.
1293 if Present
(Blk
) then
1294 Expand_At_End_Handler
1295 (Handled_Statement_Sequence
(Blk
), Entity
(Identifier
(Blk
)));
1297 end Expand_Unc_Deallocation
;
1299 -----------------------
1300 -- Expand_To_Address --
1301 -----------------------
1303 procedure Expand_To_Address
(N
: Node_Id
) is
1304 Loc
: constant Source_Ptr
:= Sloc
(N
);
1305 Arg
: constant Node_Id
:= First_Actual
(N
);
1309 Remove_Side_Effects
(Arg
);
1311 Obj
:= Make_Explicit_Dereference
(Loc
, Relocate_Node
(Arg
));
1314 Make_If_Expression
(Loc
,
1315 Expressions
=> New_List
(
1317 Left_Opnd
=> New_Copy_Tree
(Arg
),
1318 Right_Opnd
=> Make_Null
(Loc
)),
1319 New_Occurrence_Of
(RTE
(RE_Null_Address
), Loc
),
1320 Make_Attribute_Reference
(Loc
,
1322 Attribute_Name
=> Name_Address
))));
1324 Analyze_And_Resolve
(N
, RTE
(RE_Address
));
1325 end Expand_To_Address
;
1327 -----------------------
1328 -- Expand_To_Pointer --
1329 -----------------------
1331 procedure Expand_To_Pointer
(N
: Node_Id
) is
1332 Arg
: constant Node_Id
:= First_Actual
(N
);
1335 Rewrite
(N
, Unchecked_Convert_To
(Etype
(N
), Arg
));
1337 end Expand_To_Pointer
;