1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2013, 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 Expander
; use Expander
;
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 -- Remove side effects from tag argument early, before rewriting
214 -- the dispatching constructor call, as Remove_Side_Effects relies
215 -- on Tag_Arg's Parent link properly attached to the tree (once the
216 -- call is rewritten, the Parent is inconsistent as it points to the
217 -- rewritten node, which is not the syntactic parent of the Tag_Arg
220 Remove_Side_Effects
(Tag_Arg
);
222 -- The subprogram is the third actual in the instantiation, and is
223 -- retrieved from the corresponding renaming declaration. However,
224 -- freeze nodes may appear before, so we retrieve the declaration
225 -- with an explicit loop.
227 Act_Rename
:= First
(Visible_Declarations
(Inst_Pkg
));
228 while Nkind
(Act_Rename
) /= N_Subprogram_Renaming_Declaration
loop
232 Act_Constr
:= Entity
(Name
(Act_Rename
));
233 Result_Typ
:= Class_Wide_Type
(Etype
(Act_Constr
));
235 if Is_Interface
(Etype
(Act_Constr
)) then
237 -- If the result type is not known to be a parent of Tag_Arg then we
238 -- need to locate the tag of the secondary dispatch table.
240 if not Is_Ancestor
(Etype
(Result_Typ
), Etype
(Tag_Arg
),
241 Use_Full_View
=> True)
242 and then Tagged_Type_Expansion
244 -- Obtain the reference to the Ada.Tags service before generating
245 -- the Object_Declaration node to ensure that if this service is
246 -- not available in the runtime then we generate a clear error.
249 Fname
: constant Node_Id
:=
250 New_Occurrence_Of
(RTE
(RE_Secondary_Tag
), Loc
);
253 pragma Assert
(not Is_Interface
(Etype
(Tag_Arg
)));
256 Make_Object_Declaration
(Loc
,
257 Defining_Identifier
=> Make_Temporary
(Loc
, 'V'),
259 New_Occurrence_Of
(RTE
(RE_Tag
), Loc
),
261 Make_Function_Call
(Loc
,
263 Parameter_Associations
=> New_List
(
264 Relocate_Node
(Tag_Arg
),
266 (Node
(First_Elmt
(Access_Disp_Table
267 (Etype
(Etype
(Act_Constr
))))),
269 Insert_Action
(N
, Iface_Tag
);
274 -- Create the call to the actual Constructor function
277 Make_Function_Call
(Loc
,
278 Name
=> New_Occurrence_Of
(Act_Constr
, Loc
),
279 Parameter_Associations
=> New_List
(Relocate_Node
(Param_Arg
)));
281 -- Establish its controlling tag from the tag passed to the instance
282 -- The tag may be given by a function call, in which case a temporary
283 -- should be generated now, to prevent out-of-order insertions during
284 -- the expansion of that call when stack-checking is enabled.
286 if Present
(Iface_Tag
) then
287 Set_Controlling_Argument
(Cnstr_Call
,
288 New_Occurrence_Of
(Defining_Identifier
(Iface_Tag
), Loc
));
290 Set_Controlling_Argument
(Cnstr_Call
,
291 Relocate_Node
(Tag_Arg
));
294 -- Rewrite and analyze the call to the instance as a class-wide
295 -- conversion of the call to the actual constructor.
297 Rewrite
(N
, Convert_To
(Result_Typ
, Cnstr_Call
));
298 Analyze_And_Resolve
(N
, Etype
(Act_Constr
));
300 -- Do not generate a run-time check on the built object if tag
301 -- checks are suppressed for the result type or VM_Target /= No_VM
303 if Tag_Checks_Suppressed
(Etype
(Result_Typ
))
304 or else not Tagged_Type_Expansion
308 -- Generate a class-wide membership test to ensure that the call's tag
309 -- argument denotes a type within the class. We must keep separate the
310 -- case in which the Result_Type of the constructor function is a tagged
311 -- type from the case in which it is an abstract interface because the
312 -- run-time subprogram required to check these cases differ (and have
313 -- one difference in their parameters profile).
315 -- Call CW_Membership if the Result_Type is a tagged type to look for
316 -- the tag in the table of ancestor tags.
318 elsif not Is_Interface
(Result_Typ
) then
320 Obj_Tag_Node
: Node_Id
:= New_Copy_Tree
(Tag_Arg
);
321 CW_Test_Node
: Node_Id
;
324 Build_CW_Membership
(Loc
,
325 Obj_Tag_Node
=> Obj_Tag_Node
,
328 Node
(First_Elmt
(Access_Disp_Table
(
329 Root_Type
(Result_Typ
)))), Loc
),
331 New_Node
=> CW_Test_Node
);
334 Make_Implicit_If_Statement
(N
,
336 Make_Op_Not
(Loc
, CW_Test_Node
),
338 New_List
(Make_Raise_Statement
(Loc
,
339 New_Occurrence_Of
(RTE
(RE_Tag_Error
), Loc
)))));
342 -- Call IW_Membership test if the Result_Type is an abstract interface
343 -- to look for the tag in the table of interface tags.
347 Make_Implicit_If_Statement
(N
,
350 Make_Function_Call
(Loc
,
351 Name
=> New_Occurrence_Of
(RTE
(RE_IW_Membership
), Loc
),
352 Parameter_Associations
=> New_List
(
353 Make_Attribute_Reference
(Loc
,
354 Prefix
=> New_Copy_Tree
(Tag_Arg
),
355 Attribute_Name
=> Name_Address
),
358 Node
(First_Elmt
(Access_Disp_Table
(
359 Root_Type
(Result_Typ
)))), Loc
)))),
362 Make_Raise_Statement
(Loc
,
363 Name
=> New_Occurrence_Of
(RTE
(RE_Tag_Error
), Loc
)))));
365 end Expand_Dispatching_Constructor_Call
;
367 ---------------------------
368 -- Expand_Exception_Call --
369 ---------------------------
371 -- If the function call is not within an exception handler, then the call
372 -- is replaced by a null string. Otherwise the appropriate routine in
373 -- Ada.Exceptions is called passing the choice parameter specification
374 -- from the enclosing handler. If the enclosing handler lacks a choice
375 -- parameter, then one is supplied.
377 procedure Expand_Exception_Call
(N
: Node_Id
; Ent
: RE_Id
) is
378 Loc
: constant Source_Ptr
:= Sloc
(N
);
383 -- Climb up parents to see if we are in exception handler
387 -- Case of not in exception handler, replace by null string
391 Make_String_Literal
(Loc
,
395 -- Case of in exception handler
397 elsif Nkind
(P
) = N_Exception_Handler
then
399 -- Handler cannot be used for a local raise, and furthermore, this
400 -- is a violation of the No_Exception_Propagation restriction.
402 Set_Local_Raise_Not_OK
(P
);
403 Check_Restriction
(No_Exception_Propagation
, N
);
405 -- If no choice parameter present, then put one there. Note that
406 -- we do not need to put it on the entity chain, since no one will
407 -- be referencing it by normal visibility methods.
409 if No
(Choice_Parameter
(P
)) then
410 E
:= Make_Temporary
(Loc
, 'E');
411 Set_Choice_Parameter
(P
, E
);
412 Set_Ekind
(E
, E_Variable
);
413 Set_Etype
(E
, RTE
(RE_Exception_Occurrence
));
414 Set_Scope
(E
, Current_Scope
);
418 Make_Function_Call
(Loc
,
419 Name
=> New_Occurrence_Of
(RTE
(Ent
), Loc
),
420 Parameter_Associations
=> New_List
(
421 New_Occurrence_Of
(Choice_Parameter
(P
), Loc
))));
431 Analyze_And_Resolve
(N
, Standard_String
);
432 end Expand_Exception_Call
;
434 ------------------------
435 -- Expand_Import_Call --
436 ------------------------
438 -- The function call must have a static string as its argument. We create
439 -- a dummy variable which uses this string as the external name in an
440 -- Import pragma. The result is then obtained as the address of this
441 -- dummy variable, converted to the appropriate target type.
443 procedure Expand_Import_Call
(N
: Node_Id
) is
444 Loc
: constant Source_Ptr
:= Sloc
(N
);
445 Ent
: constant Entity_Id
:= Entity
(Name
(N
));
446 Str
: constant Node_Id
:= First_Actual
(N
);
447 Dum
: constant Entity_Id
:= Make_Temporary
(Loc
, 'D');
450 Insert_Actions
(N
, New_List
(
451 Make_Object_Declaration
(Loc
,
452 Defining_Identifier
=> Dum
,
454 New_Occurrence_Of
(Standard_Character
, Loc
)),
457 Chars
=> Name_Import
,
458 Pragma_Argument_Associations
=> New_List
(
459 Make_Pragma_Argument_Association
(Loc
,
460 Expression
=> Make_Identifier
(Loc
, Name_Ada
)),
462 Make_Pragma_Argument_Association
(Loc
,
463 Expression
=> Make_Identifier
(Loc
, Chars
(Dum
))),
465 Make_Pragma_Argument_Association
(Loc
,
466 Chars
=> Name_Link_Name
,
467 Expression
=> Relocate_Node
(Str
))))));
470 Unchecked_Convert_To
(Etype
(Ent
),
471 Make_Attribute_Reference
(Loc
,
472 Prefix
=> Make_Identifier
(Loc
, Chars
(Dum
)),
473 Attribute_Name
=> Name_Address
)));
475 Analyze_And_Resolve
(N
, Etype
(Ent
));
476 end Expand_Import_Call
;
478 ---------------------------
479 -- Expand_Intrinsic_Call --
480 ---------------------------
482 procedure Expand_Intrinsic_Call
(N
: Node_Id
; E
: Entity_Id
) is
486 -- If an external name is specified for the intrinsic, it is handled
487 -- by the back-end: leave the call node unchanged for now.
489 if Present
(Interface_Name
(E
)) then
493 -- If the intrinsic subprogram is generic, gets its original name
495 if Present
(Parent
(E
))
496 and then Present
(Generic_Parent
(Parent
(E
)))
498 Nam
:= Chars
(Generic_Parent
(Parent
(E
)));
503 if Nam
= Name_Asm
then
506 elsif Nam
= Name_Divide
then
507 Expand_Decimal_Divide_Call
(N
);
509 elsif Nam
= Name_Exception_Information
then
510 Expand_Exception_Call
(N
, RE_Exception_Information
);
512 elsif Nam
= Name_Exception_Message
then
513 Expand_Exception_Call
(N
, RE_Exception_Message
);
515 elsif Nam
= Name_Exception_Name
then
516 Expand_Exception_Call
(N
, RE_Exception_Name_Simple
);
518 elsif Nam
= Name_Generic_Dispatching_Constructor
then
519 Expand_Dispatching_Constructor_Call
(N
);
521 elsif Nam_In
(Nam
, Name_Import_Address
,
522 Name_Import_Largest_Value
,
525 Expand_Import_Call
(N
);
527 elsif Nam
= Name_Is_Negative
then
528 Expand_Is_Negative
(N
);
530 elsif Nam
= Name_Rotate_Left
then
531 Expand_Shift
(N
, E
, N_Op_Rotate_Left
);
533 elsif Nam
= Name_Rotate_Right
then
534 Expand_Shift
(N
, E
, N_Op_Rotate_Right
);
536 elsif Nam
= Name_Shift_Left
then
537 Expand_Shift
(N
, E
, N_Op_Shift_Left
);
539 elsif Nam
= Name_Shift_Right
then
540 Expand_Shift
(N
, E
, N_Op_Shift_Right
);
542 elsif Nam
= Name_Shift_Right_Arithmetic
then
543 Expand_Shift
(N
, E
, N_Op_Shift_Right_Arithmetic
);
545 elsif Nam
= Name_Unchecked_Conversion
then
546 Expand_Unc_Conversion
(N
, E
);
548 elsif Nam
= Name_Unchecked_Deallocation
then
549 Expand_Unc_Deallocation
(N
);
551 elsif Nam
= Name_To_Address
then
552 Expand_To_Address
(N
);
554 elsif Nam
= Name_To_Pointer
then
555 Expand_To_Pointer
(N
);
557 elsif Nam_In
(Nam
, Name_File
,
559 Name_Source_Location
,
560 Name_Enclosing_Entity
)
562 Expand_Source_Info
(N
, Nam
);
564 -- If we have a renaming, expand the call to the original operation,
565 -- which must itself be intrinsic, since renaming requires matching
566 -- conventions and this has already been checked.
568 elsif Present
(Alias
(E
)) then
569 Expand_Intrinsic_Call
(N
, Alias
(E
));
571 elsif Nkind
(N
) in N_Binary_Op
then
572 Expand_Binary_Operator_Call
(N
);
574 -- The only other case is where an external name was specified, since
575 -- this is the only way that an otherwise unrecognized name could
576 -- escape the checking in Sem_Prag. Nothing needs to be done in such
577 -- a case, since we pass such a call to the back end unchanged.
582 end Expand_Intrinsic_Call
;
584 ------------------------
585 -- Expand_Is_Negative --
586 ------------------------
588 procedure Expand_Is_Negative
(N
: Node_Id
) is
589 Loc
: constant Source_Ptr
:= Sloc
(N
);
590 Opnd
: constant Node_Id
:= Relocate_Node
(First_Actual
(N
));
594 -- We replace the function call by the following expression
596 -- if Opnd < 0.0 then
599 -- if Opnd > 0.0 then
602 -- Float_Unsigned!(Float (Opnd)) /= 0
607 Make_If_Expression
(Loc
,
608 Expressions
=> New_List
(
610 Left_Opnd
=> Duplicate_Subexpr
(Opnd
),
611 Right_Opnd
=> Make_Real_Literal
(Loc
, Ureal_0
)),
613 New_Occurrence_Of
(Standard_True
, Loc
),
615 Make_If_Expression
(Loc
,
616 Expressions
=> New_List
(
618 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Opnd
),
619 Right_Opnd
=> Make_Real_Literal
(Loc
, Ureal_0
)),
621 New_Occurrence_Of
(Standard_False
, Loc
),
626 (RTE
(RE_Float_Unsigned
),
629 Duplicate_Subexpr_No_Checks
(Opnd
))),
631 Make_Integer_Literal
(Loc
, 0)))))));
633 Analyze_And_Resolve
(N
, Standard_Boolean
);
634 end Expand_Is_Negative
;
640 -- This procedure is used to convert a call to a shift function to the
641 -- corresponding operator node. This conversion is not done by the usual
642 -- circuit for converting calls to operator functions (e.g. "+"(1,2)) to
643 -- operator nodes, because shifts are not predefined operators.
645 -- As a result, whenever a shift is used in the source program, it will
646 -- remain as a call until converted by this routine to the operator node
647 -- form which the back end is expecting to see.
649 -- Note: it is possible for the expander to generate shift operator nodes
650 -- directly, which will be analyzed in the normal manner by calling Analyze
651 -- and Resolve. Such shift operator nodes will not be seen by Expand_Shift.
653 procedure Expand_Shift
(N
: Node_Id
; E
: Entity_Id
; K
: Node_Kind
) is
654 Entyp
: constant Entity_Id
:= Etype
(E
);
655 Left
: constant Node_Id
:= First_Actual
(N
);
656 Loc
: constant Source_Ptr
:= Sloc
(N
);
657 Right
: constant Node_Id
:= Next_Actual
(Left
);
658 Ltyp
: constant Node_Id
:= Etype
(Left
);
659 Rtyp
: constant Node_Id
:= Etype
(Right
);
660 Typ
: constant Entity_Id
:= Etype
(N
);
664 Snode
:= New_Node
(K
, Loc
);
665 Set_Right_Opnd
(Snode
, Relocate_Node
(Right
));
666 Set_Chars
(Snode
, Chars
(E
));
667 Set_Etype
(Snode
, Base_Type
(Entyp
));
668 Set_Entity
(Snode
, E
);
670 if Compile_Time_Known_Value
(Type_High_Bound
(Rtyp
))
671 and then Expr_Value
(Type_High_Bound
(Rtyp
)) < Esize
(Ltyp
)
673 Set_Shift_Count_OK
(Snode
, True);
678 -- Note that we don't call Analyze and Resolve on this node, because
679 -- it already got analyzed and resolved when it was a function call.
681 Set_Left_Opnd
(Snode
, Relocate_Node
(Left
));
685 -- However, we do call the expander, so that the expansion for
686 -- rotates and shift_right_arithmetic happens if Modify_Tree_For_C
689 if Expander_Active
then
694 -- If the context type is not the type of the operator, it is an
695 -- inherited operator for a derived type. Wrap the node in a
696 -- conversion so that it is type-consistent for possible further
697 -- expansion (e.g. within a lock-free protected type).
699 Set_Left_Opnd
(Snode
,
700 Unchecked_Convert_To
(Base_Type
(Entyp
), Relocate_Node
(Left
)));
701 Rewrite
(N
, Unchecked_Convert_To
(Typ
, Snode
));
703 -- Analyze and resolve result formed by conversion to target type
705 Analyze_And_Resolve
(N
, Typ
);
709 ------------------------
710 -- Expand_Source_Info --
711 ------------------------
713 procedure Expand_Source_Info
(N
: Node_Id
; Nam
: Name_Id
) is
714 Loc
: constant Source_Ptr
:= Sloc
(N
);
717 procedure Write_Entity_Name
(E
: Entity_Id
);
718 -- Recursive procedure to construct string for qualified name of
719 -- enclosing program unit. The qualification stops at an enclosing
720 -- scope has no source name (block or loop). If entity is a subprogram
721 -- instance, skip enclosing wrapper package.
723 -----------------------
724 -- Write_Entity_Name --
725 -----------------------
727 procedure Write_Entity_Name
(E
: Entity_Id
) is
729 TDef
: constant Source_Buffer_Ptr
:=
730 Source_Text
(Get_Source_File_Index
(Sloc
(E
)));
733 -- Nothing to do if at outer level
735 if Scope
(E
) = Standard_Standard
then
738 -- If scope comes from source, write its name
740 elsif Comes_From_Source
(Scope
(E
)) then
741 Write_Entity_Name
(Scope
(E
));
742 Add_Char_To_Name_Buffer
('.');
744 -- If in wrapper package skip past it
746 elsif Is_Wrapper_Package
(Scope
(E
)) then
747 Write_Entity_Name
(Scope
(Scope
(E
)));
748 Add_Char_To_Name_Buffer
('.');
750 -- Otherwise nothing to output (happens in unnamed block statements)
756 -- Loop to output the name
758 -- This is not right wrt wide char encodings ??? ()
761 while TDef
(SDef
) in '0' .. '9'
762 or else TDef
(SDef
) >= 'A'
763 or else TDef
(SDef
) = ASCII
.ESC
765 Add_Char_To_Name_Buffer
(TDef
(SDef
));
768 end Write_Entity_Name
;
770 -- Start of processing for Expand_Source_Info
775 if Nam
= Name_Line
then
777 Make_Integer_Literal
(Loc
,
778 Intval
=> UI_From_Int
(Int
(Get_Logical_Line_Number
(Loc
)))));
779 Analyze_And_Resolve
(N
, Standard_Positive
);
788 Get_Decoded_Name_String
789 (Reference_Name
(Get_Source_File_Index
(Loc
)));
791 when Name_Source_Location
=>
792 Build_Location_String
(Loc
);
794 when Name_Enclosing_Entity
=>
796 -- Skip enclosing blocks to reach enclosing unit
798 Ent
:= Current_Scope
;
799 while Present
(Ent
) loop
800 exit when Ekind
(Ent
) /= E_Block
801 and then Ekind
(Ent
) /= E_Loop
;
805 -- Ent now points to the relevant defining entity
807 Write_Entity_Name
(Ent
);
814 Make_String_Literal
(Loc
,
815 Strval
=> String_From_Name_Buffer
));
816 Analyze_And_Resolve
(N
, Standard_String
);
819 Set_Is_Static_Expression
(N
);
820 end Expand_Source_Info
;
822 ---------------------------
823 -- Expand_Unc_Conversion --
824 ---------------------------
826 procedure Expand_Unc_Conversion
(N
: Node_Id
; E
: Entity_Id
) is
827 Func
: constant Entity_Id
:= Entity
(Name
(N
));
833 -- Rewrite as unchecked conversion node. Note that we must convert
834 -- the operand to the formal type of the input parameter of the
835 -- function, so that the resulting N_Unchecked_Type_Conversion
836 -- call indicates the correct types for Gigi.
838 -- Right now, we only do this if a scalar type is involved. It is
839 -- not clear if it is needed in other cases. If we do attempt to
840 -- do the conversion unconditionally, it crashes 3411-018. To be
841 -- investigated further ???
843 Conv
:= Relocate_Node
(First_Actual
(N
));
844 Ftyp
:= Etype
(First_Formal
(Func
));
846 if Is_Scalar_Type
(Ftyp
) then
847 Conv
:= Convert_To
(Ftyp
, Conv
);
848 Set_Parent
(Conv
, N
);
849 Analyze_And_Resolve
(Conv
);
852 -- The instantiation of Unchecked_Conversion creates a wrapper package,
853 -- and the target type is declared as a subtype of the actual. Recover
854 -- the actual, which is the subtype indic. in the subtype declaration
855 -- for the target type. This is semantically correct, and avoids
856 -- anomalies with access subtypes. For entities, leave type as is.
858 -- We do the analysis here, because we do not want the compiler
859 -- to try to optimize or otherwise reorganize the unchecked
864 if Is_Entity_Name
(Conv
) then
867 elsif Nkind
(Parent
(Ttyp
)) = N_Subtype_Declaration
then
868 Ttyp
:= Entity
(Subtype_Indication
(Parent
(Etype
(E
))));
870 elsif Is_Itype
(Ttyp
) then
872 Entity
(Subtype_Indication
(Associated_Node_For_Itype
(Ttyp
)));
877 Rewrite
(N
, Unchecked_Convert_To
(Ttyp
, Conv
));
881 if Nkind
(N
) = N_Unchecked_Type_Conversion
then
882 Expand_N_Unchecked_Type_Conversion
(N
);
884 end Expand_Unc_Conversion
;
886 -----------------------------
887 -- Expand_Unc_Deallocation --
888 -----------------------------
890 -- Generate the following Code :
892 -- if Arg /= null then
893 -- <Finalize_Call> (.., T'Class(Arg.all), ..); -- for controlled types
898 -- For a task, we also generate a call to Free_Task to ensure that the
899 -- task itself is freed if it is terminated, ditto for a simple protected
900 -- object, with a call to Finalize_Protection. For composite types that
901 -- have tasks or simple protected objects as components, we traverse the
902 -- structures to find and terminate those components.
904 procedure Expand_Unc_Deallocation
(N
: Node_Id
) is
905 Arg
: constant Node_Id
:= First_Actual
(N
);
906 Loc
: constant Source_Ptr
:= Sloc
(N
);
907 Typ
: constant Entity_Id
:= Etype
(Arg
);
908 Desig_T
: constant Entity_Id
:= Designated_Type
(Typ
);
909 Rtyp
: constant Entity_Id
:= Underlying_Type
(Root_Type
(Typ
));
910 Pool
: constant Entity_Id
:= Associated_Storage_Pool
(Rtyp
);
911 Stmts
: constant List_Id
:= New_List
;
912 Needs_Fin
: constant Boolean := Needs_Finalization
(Desig_T
);
914 Finalizer_Data
: Finalization_Exception_Data
;
916 Blk
: Node_Id
:= Empty
;
918 Final_Code
: List_Id
;
923 Arg_Known_Non_Null
: constant Boolean := Known_Non_Null
(N
);
924 -- This captures whether we know the argument to be non-null so that
925 -- we can avoid the test. The reason that we need to capture this is
926 -- that we analyze some generated statements before properly attaching
927 -- them to the tree, and that can disturb current value settings.
930 -- Nothing to do if we know the argument is null
932 if Known_Null
(N
) then
936 -- Processing for pointer to controlled type
940 Make_Explicit_Dereference
(Loc
,
941 Prefix
=> Duplicate_Subexpr_No_Checks
(Arg
));
943 -- If the type is tagged, then we must force dispatching on the
944 -- finalization call because the designated type may not be the
945 -- actual type of the object.
947 if Is_Tagged_Type
(Desig_T
)
948 and then not Is_Class_Wide_Type
(Desig_T
)
950 Deref
:= Unchecked_Convert_To
(Class_Wide_Type
(Desig_T
), Deref
);
952 elsif not Is_Tagged_Type
(Desig_T
) then
954 -- Set type of result, to force a conversion when needed (see
955 -- exp_ch7, Convert_View), given that Deep_Finalize may be
956 -- inherited from the parent type, and we need the type of the
957 -- expression to see whether the conversion is in fact needed.
959 Set_Etype
(Deref
, Desig_T
);
962 -- The finalization call is expanded wrapped in a block to catch any
963 -- possible exception. If an exception does occur, then Program_Error
964 -- must be raised following the freeing of the object and its removal
965 -- from the finalization collection's list. We set a flag to record
966 -- that an exception was raised, and save its occurrence for use in
970 -- Abort : constant Boolean :=
971 -- Exception_Occurrence (Get_Current_Excep.all.all) =
972 -- Standard'Abort_Signal'Identity;
974 -- Abort : constant Boolean := False; -- no abort
976 -- E : Exception_Occurrence;
977 -- Raised : Boolean := False;
980 -- [Deep_]Finalize (Obj);
984 -- Save_Occurrence (E, Get_Current_Excep.all.all);
987 Build_Object_Declarations
(Finalizer_Data
, Stmts
, Loc
);
989 Final_Code
:= New_List
(
990 Make_Block_Statement
(Loc
,
991 Handled_Statement_Sequence
=>
992 Make_Handled_Sequence_Of_Statements
(Loc
,
993 Statements
=> New_List
(
994 Make_Final_Call
(Obj_Ref
=> Deref
, Typ
=> Desig_T
)),
995 Exception_Handlers
=> New_List
(
996 Build_Exception_Handler
(Finalizer_Data
)))));
998 -- For .NET/JVM, detach the object from the containing finalization
999 -- collection before finalizing it.
1001 if VM_Target
/= No_VM
and then Is_Controlled
(Desig_T
) then
1002 Prepend_To
(Final_Code
,
1003 Make_Detach_Call
(New_Copy_Tree
(Arg
)));
1006 -- If aborts are allowed, then the finalization code must be
1007 -- protected by an abort defer/undefer pair.
1009 if Abort_Allowed
then
1010 Prepend_To
(Final_Code
,
1011 Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
1014 Make_Block_Statement
(Loc
, Handled_Statement_Sequence
=>
1015 Make_Handled_Sequence_Of_Statements
(Loc
,
1016 Statements
=> Final_Code
,
1018 New_Occurrence_Of
(RTE
(RE_Abort_Undefer_Direct
), Loc
)));
1020 Append
(Blk
, Stmts
);
1022 Append_List_To
(Stmts
, Final_Code
);
1026 -- For a task type, call Free_Task before freeing the ATCB
1028 if Is_Task_Type
(Desig_T
) then
1030 -- We used to detect the case of Abort followed by a Free here,
1031 -- because the Free wouldn't actually free if it happens before
1032 -- the aborted task actually terminates. The warning was removed,
1033 -- because Free now works properly (the task will be freed once
1037 (Stmts
, Cleanup_Task
(N
, Duplicate_Subexpr_No_Checks
(Arg
)));
1039 -- For composite types that contain tasks, recurse over the structure
1040 -- to build the selectors for the task subcomponents.
1042 elsif Has_Task
(Desig_T
) then
1043 if Is_Record_Type
(Desig_T
) then
1044 Append_List_To
(Stmts
, Cleanup_Record
(N
, Arg
, Desig_T
));
1046 elsif Is_Array_Type
(Desig_T
) then
1047 Append_List_To
(Stmts
, Cleanup_Array
(N
, Arg
, Desig_T
));
1051 -- Same for simple protected types. Eventually call Finalize_Protection
1052 -- before freeing the PO for each protected component.
1054 if Is_Simple_Protected_Type
(Desig_T
) then
1056 Cleanup_Protected_Object
(N
, Duplicate_Subexpr_No_Checks
(Arg
)));
1058 elsif Has_Simple_Protected_Object
(Desig_T
) then
1059 if Is_Record_Type
(Desig_T
) then
1060 Append_List_To
(Stmts
, Cleanup_Record
(N
, Arg
, Desig_T
));
1061 elsif Is_Array_Type
(Desig_T
) then
1062 Append_List_To
(Stmts
, Cleanup_Array
(N
, Arg
, Desig_T
));
1066 -- Normal processing for non-controlled types
1068 Free_Arg
:= Duplicate_Subexpr_No_Checks
(Arg
);
1069 Free_Node
:= Make_Free_Statement
(Loc
, Empty
);
1070 Append_To
(Stmts
, Free_Node
);
1071 Set_Storage_Pool
(Free_Node
, Pool
);
1073 -- Attach to tree before analysis of generated subtypes below
1075 Set_Parent
(Stmts
, Parent
(N
));
1077 -- Deal with storage pool
1079 if Present
(Pool
) then
1081 -- Freeing the secondary stack is meaningless
1083 if Is_RTE
(Pool
, RE_SS_Pool
) then
1086 -- If the pool object is of a simple storage pool type, then attempt
1087 -- to locate the type's Deallocate procedure, if any, and set the
1088 -- free operation's procedure to call. If the type doesn't have a
1089 -- Deallocate (which is allowed), then the actual will simply be set
1092 elsif Present
(Get_Rep_Pragma
1093 (Etype
(Pool
), Name_Simple_Storage_Pool_Type
))
1096 Pool_Type
: constant Entity_Id
:= Base_Type
(Etype
(Pool
));
1097 Dealloc_Op
: Entity_Id
;
1099 Dealloc_Op
:= Get_Name_Entity_Id
(Name_Deallocate
);
1100 while Present
(Dealloc_Op
) loop
1101 if Scope
(Dealloc_Op
) = Scope
(Pool_Type
)
1102 and then Present
(First_Formal
(Dealloc_Op
))
1103 and then Etype
(First_Formal
(Dealloc_Op
)) = Pool_Type
1105 Set_Procedure_To_Call
(Free_Node
, Dealloc_Op
);
1108 Dealloc_Op
:= Homonym
(Dealloc_Op
);
1113 -- Case of a class-wide pool type: make a dispatching call to
1114 -- Deallocate through the class-wide Deallocate_Any.
1116 elsif Is_Class_Wide_Type
(Etype
(Pool
)) then
1117 Set_Procedure_To_Call
(Free_Node
, RTE
(RE_Deallocate_Any
));
1119 -- Case of a specific pool type: make a statically bound call
1122 Set_Procedure_To_Call
(Free_Node
,
1123 Find_Prim_Op
(Etype
(Pool
), Name_Deallocate
));
1127 if Present
(Procedure_To_Call
(Free_Node
)) then
1129 -- For all cases of a Deallocate call, the back-end needs to be able
1130 -- to compute the size of the object being freed. This may require
1131 -- some adjustments for objects of dynamic size.
1133 -- If the type is class wide, we generate an implicit type with the
1134 -- right dynamic size, so that the deallocate call gets the right
1135 -- size parameter computed by GIGI. Same for an access to
1136 -- unconstrained packed array.
1138 if Is_Class_Wide_Type
(Desig_T
)
1140 (Is_Array_Type
(Desig_T
)
1141 and then not Is_Constrained
(Desig_T
)
1142 and then Is_Packed
(Desig_T
))
1145 Deref
: constant Node_Id
:=
1146 Make_Explicit_Dereference
(Loc
,
1147 Duplicate_Subexpr_No_Checks
(Arg
));
1152 -- Perform minor decoration as it is needed by the side effect
1153 -- removal mechanism.
1155 Set_Etype
(Deref
, Desig_T
);
1156 Set_Parent
(Deref
, Free_Node
);
1157 D_Subtyp
:= Make_Subtype_From_Expr
(Deref
, Desig_T
);
1159 if Nkind
(D_Subtyp
) in N_Has_Entity
then
1160 D_Type
:= Entity
(D_Subtyp
);
1163 D_Type
:= Make_Temporary
(Loc
, 'A');
1164 Insert_Action
(Deref
,
1165 Make_Subtype_Declaration
(Loc
,
1166 Defining_Identifier
=> D_Type
,
1167 Subtype_Indication
=> D_Subtyp
));
1170 -- Force freezing at the point of the dereference. For the
1171 -- class wide case, this avoids having the subtype frozen
1172 -- before the equivalent type.
1174 Freeze_Itype
(D_Type
, Deref
);
1176 Set_Actual_Designated_Subtype
(Free_Node
, D_Type
);
1182 -- Ada 2005 (AI-251): In case of abstract interface type we must
1183 -- displace the pointer to reference the base of the object to
1184 -- deallocate its memory, unless we're targetting a VM, in which case
1185 -- no special processing is required.
1188 -- free (Base_Address (Obj_Ptr))
1190 if Is_Interface
(Directly_Designated_Type
(Typ
))
1191 and then Tagged_Type_Expansion
1193 Set_Expression
(Free_Node
,
1194 Unchecked_Convert_To
(Typ
,
1195 Make_Function_Call
(Loc
,
1196 Name
=> New_Occurrence_Of
(RTE
(RE_Base_Address
), Loc
),
1197 Parameter_Associations
=> New_List
(
1198 Unchecked_Convert_To
(RTE
(RE_Address
), Free_Arg
)))));
1204 Set_Expression
(Free_Node
, Free_Arg
);
1207 -- Only remaining step is to set result to null, or generate a raise of
1208 -- Constraint_Error if the target object is "not null".
1210 if Can_Never_Be_Null
(Etype
(Arg
)) then
1212 Make_Raise_Constraint_Error
(Loc
,
1213 Reason
=> CE_Access_Check_Failed
));
1217 Lhs
: constant Node_Id
:= Duplicate_Subexpr_No_Checks
(Arg
);
1219 Set_Assignment_OK
(Lhs
);
1221 Make_Assignment_Statement
(Loc
,
1223 Expression
=> Make_Null
(Loc
)));
1227 -- Generate a test of whether any earlier finalization raised an
1228 -- exception, and in that case raise Program_Error with the previous
1229 -- exception occurrence.
1232 -- if Raised and then not Abort then
1233 -- raise Program_Error; -- for .NET and
1234 -- -- restricted RTS
1236 -- Raise_From_Controlled_Operation (E); -- all other cases
1240 Append_To
(Stmts
, Build_Raise_Statement
(Finalizer_Data
));
1243 -- If we know the argument is non-null, then make a block statement
1244 -- that contains the required statements, no need for a test.
1246 if Arg_Known_Non_Null
then
1248 Make_Block_Statement
(Loc
,
1249 Handled_Statement_Sequence
=>
1250 Make_Handled_Sequence_Of_Statements
(Loc
,
1251 Statements
=> Stmts
));
1253 -- If the argument may be null, wrap the statements inside an IF that
1254 -- does an explicit test to exclude the null case.
1258 Make_Implicit_If_Statement
(N
,
1261 Left_Opnd
=> Duplicate_Subexpr
(Arg
),
1262 Right_Opnd
=> Make_Null
(Loc
)),
1263 Then_Statements
=> Stmts
);
1268 Rewrite
(N
, Gen_Code
);
1271 -- If we generated a block with an At_End_Proc, expand the exception
1272 -- handler. We need to wait until after everything else is analyzed.
1274 if Present
(Blk
) then
1275 Expand_At_End_Handler
1276 (Handled_Statement_Sequence
(Blk
), Entity
(Identifier
(Blk
)));
1278 end Expand_Unc_Deallocation
;
1280 -----------------------
1281 -- Expand_To_Address --
1282 -----------------------
1284 procedure Expand_To_Address
(N
: Node_Id
) is
1285 Loc
: constant Source_Ptr
:= Sloc
(N
);
1286 Arg
: constant Node_Id
:= First_Actual
(N
);
1290 Remove_Side_Effects
(Arg
);
1292 Obj
:= Make_Explicit_Dereference
(Loc
, Relocate_Node
(Arg
));
1295 Make_If_Expression
(Loc
,
1296 Expressions
=> New_List
(
1298 Left_Opnd
=> New_Copy_Tree
(Arg
),
1299 Right_Opnd
=> Make_Null
(Loc
)),
1300 New_Occurrence_Of
(RTE
(RE_Null_Address
), Loc
),
1301 Make_Attribute_Reference
(Loc
,
1303 Attribute_Name
=> Name_Address
))));
1305 Analyze_And_Resolve
(N
, RTE
(RE_Address
));
1306 end Expand_To_Address
;
1308 -----------------------
1309 -- Expand_To_Pointer --
1310 -----------------------
1312 procedure Expand_To_Pointer
(N
: Node_Id
) is
1313 Arg
: constant Node_Id
:= First_Actual
(N
);
1316 Rewrite
(N
, Unchecked_Convert_To
(Etype
(N
), Arg
));
1318 end Expand_To_Pointer
;