1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2016, 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 Aspects
; use Aspects
;
27 with Atree
; use Atree
;
28 with Casing
; use Casing
;
29 with Checks
; use Checks
;
30 with Debug
; use Debug
;
31 with Einfo
; use Einfo
;
32 with Elists
; use Elists
;
33 with Errout
; use Errout
;
34 with Exp_Aggr
; use Exp_Aggr
;
35 with Exp_Ch6
; use Exp_Ch6
;
36 with Exp_Ch7
; use Exp_Ch7
;
37 with Ghost
; use Ghost
;
38 with Inline
; use Inline
;
39 with Itypes
; use Itypes
;
41 with Nlists
; use Nlists
;
42 with Nmake
; use Nmake
;
44 with Restrict
; use Restrict
;
45 with Rident
; use Rident
;
47 with Sem_Aux
; use Sem_Aux
;
48 with Sem_Ch8
; use Sem_Ch8
;
49 with Sem_Ch13
; use Sem_Ch13
;
50 with Sem_Eval
; use Sem_Eval
;
51 with Sem_Res
; use Sem_Res
;
52 with Sem_Type
; use Sem_Type
;
53 with Sem_Util
; use Sem_Util
;
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 Ttypes
; use Ttypes
;
60 with Urealp
; use Urealp
;
61 with Validsw
; use Validsw
;
63 package body Exp_Util
is
65 -----------------------
66 -- Local Subprograms --
67 -----------------------
69 function Build_Task_Array_Image
73 Dyn
: Boolean := False) return Node_Id
;
74 -- Build function to generate the image string for a task that is an array
75 -- component, concatenating the images of each index. To avoid storage
76 -- leaks, the string is built with successive slice assignments. The flag
77 -- Dyn indicates whether this is called for the initialization procedure of
78 -- an array of tasks, or for the name of a dynamically created task that is
79 -- assigned to an indexed component.
81 function Build_Task_Image_Function
85 Res
: Entity_Id
) return Node_Id
;
86 -- Common processing for Task_Array_Image and Task_Record_Image. Build
87 -- function body that computes image.
89 procedure Build_Task_Image_Prefix
98 -- Common processing for Task_Array_Image and Task_Record_Image. Create
99 -- local variables and assign prefix of name to result string.
101 function Build_Task_Record_Image
104 Dyn
: Boolean := False) return Node_Id
;
105 -- Build function to generate the image string for a task that is a record
106 -- component. Concatenate name of variable with that of selector. The flag
107 -- Dyn indicates whether this is called for the initialization procedure of
108 -- record with task components, or for a dynamically created task that is
109 -- assigned to a selected component.
111 procedure Evaluate_Slice_Bounds
(Slice
: Node_Id
);
112 -- Force evaluation of bounds of a slice, which may be given by a range
113 -- or by a subtype indication with or without a constraint.
115 function Make_CW_Equivalent_Type
117 E
: Node_Id
) return Entity_Id
;
118 -- T is a class-wide type entity, E is the initial expression node that
119 -- constrains T in case such as: " X: T := E" or "new T'(E)". This function
120 -- returns the entity of the Equivalent type and inserts on the fly the
121 -- necessary declaration such as:
123 -- type anon is record
124 -- _parent : Root_Type (T); constrained with E discriminants (if any)
125 -- Extension : String (1 .. expr to match size of E);
128 -- This record is compatible with any object of the class of T thanks to
129 -- the first field and has the same size as E thanks to the second.
131 function Make_Literal_Range
133 Literal_Typ
: Entity_Id
) return Node_Id
;
134 -- Produce a Range node whose bounds are:
135 -- Low_Bound (Literal_Type) ..
136 -- Low_Bound (Literal_Type) + (Length (Literal_Typ) - 1)
137 -- this is used for expanding declarations like X : String := "sdfgdfg";
139 -- If the index type of the target array is not integer, we generate:
140 -- Low_Bound (Literal_Type) ..
142 -- (Literal_Type'Pos (Low_Bound (Literal_Type))
143 -- + (Length (Literal_Typ) -1))
145 function Make_Non_Empty_Check
147 N
: Node_Id
) return Node_Id
;
148 -- Produce a boolean expression checking that the unidimensional array
149 -- node N is not empty.
151 function New_Class_Wide_Subtype
153 N
: Node_Id
) return Entity_Id
;
154 -- Create an implicit subtype of CW_Typ attached to node N
156 function Requires_Cleanup_Actions
159 Nested_Constructs
: Boolean) return Boolean;
160 -- Given a list L, determine whether it contains one of the following:
162 -- 1) controlled objects
163 -- 2) library-level tagged types
165 -- Lib_Level is True when the list comes from a construct at the library
166 -- level, and False otherwise. Nested_Constructs is True when any nested
167 -- packages declared in L must be processed, and False otherwise.
169 -------------------------------------
170 -- Activate_Atomic_Synchronization --
171 -------------------------------------
173 procedure Activate_Atomic_Synchronization
(N
: Node_Id
) is
177 case Nkind
(Parent
(N
)) is
179 -- Check for cases of appearing in the prefix of a construct where
180 -- we don't need atomic synchronization for this kind of usage.
183 -- Nothing to do if we are the prefix of an attribute, since we
184 -- do not want an atomic sync operation for things like 'Size.
186 N_Attribute_Reference |
188 -- The N_Reference node is like an attribute
192 -- Nothing to do for a reference to a component (or components)
193 -- of a composite object. Only reads and updates of the object
194 -- as a whole require atomic synchronization (RM C.6 (15)).
196 N_Indexed_Component |
197 N_Selected_Component |
200 -- For all the above cases, nothing to do if we are the prefix
202 if Prefix
(Parent
(N
)) = N
then
209 -- Nothing to do for the identifier in an object renaming declaration,
210 -- the renaming itself does not need atomic synchronization.
212 if Nkind
(Parent
(N
)) = N_Object_Renaming_Declaration
then
216 -- Go ahead and set the flag
218 Set_Atomic_Sync_Required
(N
);
220 -- Generate info message if requested
222 if Warn_On_Atomic_Synchronization
then
227 when N_Selected_Component | N_Expanded_Name
=>
228 Msg_Node
:= Selector_Name
(N
);
230 when N_Explicit_Dereference | N_Indexed_Component
=>
234 pragma Assert
(False);
238 if Present
(Msg_Node
) then
240 ("info: atomic synchronization set for &?N?", Msg_Node
);
243 ("info: atomic synchronization set?N?", N
);
246 end Activate_Atomic_Synchronization
;
248 ----------------------
249 -- Adjust_Condition --
250 ----------------------
252 procedure Adjust_Condition
(N
: Node_Id
) is
259 Loc
: constant Source_Ptr
:= Sloc
(N
);
260 T
: constant Entity_Id
:= Etype
(N
);
264 -- Defend against a call where the argument has no type, or has a
265 -- type that is not Boolean. This can occur because of prior errors.
267 if No
(T
) or else not Is_Boolean_Type
(T
) then
271 -- Apply validity checking if needed
273 if Validity_Checks_On
and Validity_Check_Tests
then
277 -- Immediate return if standard boolean, the most common case,
278 -- where nothing needs to be done.
280 if Base_Type
(T
) = Standard_Boolean
then
284 -- Case of zero/non-zero semantics or non-standard enumeration
285 -- representation. In each case, we rewrite the node as:
287 -- ityp!(N) /= False'Enum_Rep
289 -- where ityp is an integer type with large enough size to hold any
292 if Nonzero_Is_True
(T
) or else Has_Non_Standard_Rep
(T
) then
293 if Esize
(T
) <= Esize
(Standard_Integer
) then
294 Ti
:= Standard_Integer
;
296 Ti
:= Standard_Long_Long_Integer
;
301 Left_Opnd
=> Unchecked_Convert_To
(Ti
, N
),
303 Make_Attribute_Reference
(Loc
,
304 Attribute_Name
=> Name_Enum_Rep
,
306 New_Occurrence_Of
(First_Literal
(T
), Loc
))));
307 Analyze_And_Resolve
(N
, Standard_Boolean
);
310 Rewrite
(N
, Convert_To
(Standard_Boolean
, N
));
311 Analyze_And_Resolve
(N
, Standard_Boolean
);
314 end Adjust_Condition
;
316 ------------------------
317 -- Adjust_Result_Type --
318 ------------------------
320 procedure Adjust_Result_Type
(N
: Node_Id
; T
: Entity_Id
) is
322 -- Ignore call if current type is not Standard.Boolean
324 if Etype
(N
) /= Standard_Boolean
then
328 -- If result is already of correct type, nothing to do. Note that
329 -- this will get the most common case where everything has a type
330 -- of Standard.Boolean.
332 if Base_Type
(T
) = Standard_Boolean
then
337 KP
: constant Node_Kind
:= Nkind
(Parent
(N
));
340 -- If result is to be used as a Condition in the syntax, no need
341 -- to convert it back, since if it was changed to Standard.Boolean
342 -- using Adjust_Condition, that is just fine for this usage.
344 if KP
in N_Raise_xxx_Error
or else KP
in N_Has_Condition
then
347 -- If result is an operand of another logical operation, no need
348 -- to reset its type, since Standard.Boolean is just fine, and
349 -- such operations always do Adjust_Condition on their operands.
351 elsif KP
in N_Op_Boolean
352 or else KP
in N_Short_Circuit
353 or else KP
= N_Op_Not
357 -- Otherwise we perform a conversion from the current type, which
358 -- must be Standard.Boolean, to the desired type.
362 Rewrite
(N
, Convert_To
(T
, N
));
363 Analyze_And_Resolve
(N
, T
);
367 end Adjust_Result_Type
;
369 --------------------------
370 -- Append_Freeze_Action --
371 --------------------------
373 procedure Append_Freeze_Action
(T
: Entity_Id
; N
: Node_Id
) is
377 Ensure_Freeze_Node
(T
);
378 Fnode
:= Freeze_Node
(T
);
380 if No
(Actions
(Fnode
)) then
381 Set_Actions
(Fnode
, New_List
(N
));
383 Append
(N
, Actions
(Fnode
));
386 end Append_Freeze_Action
;
388 ---------------------------
389 -- Append_Freeze_Actions --
390 ---------------------------
392 procedure Append_Freeze_Actions
(T
: Entity_Id
; L
: List_Id
) is
400 Ensure_Freeze_Node
(T
);
401 Fnode
:= Freeze_Node
(T
);
403 if No
(Actions
(Fnode
)) then
404 Set_Actions
(Fnode
, L
);
406 Append_List
(L
, Actions
(Fnode
));
408 end Append_Freeze_Actions
;
410 ------------------------------------
411 -- Build_Allocate_Deallocate_Proc --
412 ------------------------------------
414 procedure Build_Allocate_Deallocate_Proc
416 Is_Allocate
: Boolean)
418 Desig_Typ
: Entity_Id
;
421 Proc_To_Call
: Node_Id
:= Empty
;
424 function Find_Object
(E
: Node_Id
) return Node_Id
;
425 -- Given an arbitrary expression of an allocator, try to find an object
426 -- reference in it, otherwise return the original expression.
428 function Is_Allocate_Deallocate_Proc
(Subp
: Entity_Id
) return Boolean;
429 -- Determine whether subprogram Subp denotes a custom allocate or
436 function Find_Object
(E
: Node_Id
) return Node_Id
is
440 pragma Assert
(Is_Allocate
);
444 if Nkind
(Expr
) = N_Explicit_Dereference
then
445 Expr
:= Prefix
(Expr
);
447 elsif Nkind
(Expr
) = N_Qualified_Expression
then
448 Expr
:= Expression
(Expr
);
450 elsif Nkind
(Expr
) = N_Unchecked_Type_Conversion
then
452 -- When interface class-wide types are involved in allocation,
453 -- the expander introduces several levels of address arithmetic
454 -- to perform dispatch table displacement. In this scenario the
455 -- object appears as:
457 -- Tag_Ptr (Base_Address (<object>'Address))
459 -- Detect this case and utilize the whole expression as the
460 -- "object" since it now points to the proper dispatch table.
462 if Is_RTE
(Etype
(Expr
), RE_Tag_Ptr
) then
465 -- Continue to strip the object
468 Expr
:= Expression
(Expr
);
479 ---------------------------------
480 -- Is_Allocate_Deallocate_Proc --
481 ---------------------------------
483 function Is_Allocate_Deallocate_Proc
(Subp
: Entity_Id
) return Boolean is
485 -- Look for a subprogram body with only one statement which is a
486 -- call to Allocate_Any_Controlled / Deallocate_Any_Controlled.
488 if Ekind
(Subp
) = E_Procedure
489 and then Nkind
(Parent
(Parent
(Subp
))) = N_Subprogram_Body
492 HSS
: constant Node_Id
:=
493 Handled_Statement_Sequence
(Parent
(Parent
(Subp
)));
497 if Present
(Statements
(HSS
))
498 and then Nkind
(First
(Statements
(HSS
))) =
499 N_Procedure_Call_Statement
501 Proc
:= Entity
(Name
(First
(Statements
(HSS
))));
504 Is_RTE
(Proc
, RE_Allocate_Any_Controlled
)
505 or else Is_RTE
(Proc
, RE_Deallocate_Any_Controlled
);
511 end Is_Allocate_Deallocate_Proc
;
513 -- Start of processing for Build_Allocate_Deallocate_Proc
516 -- Obtain the attributes of the allocation / deallocation
518 if Nkind
(N
) = N_Free_Statement
then
519 Expr
:= Expression
(N
);
520 Ptr_Typ
:= Base_Type
(Etype
(Expr
));
521 Proc_To_Call
:= Procedure_To_Call
(N
);
524 if Nkind
(N
) = N_Object_Declaration
then
525 Expr
:= Expression
(N
);
530 -- In certain cases an allocator with a qualified expression may
531 -- be relocated and used as the initialization expression of a
535 -- Obj : Ptr_Typ := new Desig_Typ'(...);
538 -- Tmp : Ptr_Typ := new Desig_Typ'(...);
539 -- Obj : Ptr_Typ := Tmp;
541 -- Since the allocator is always marked as analyzed to avoid infinite
542 -- expansion, it will never be processed by this routine given that
543 -- the designated type needs finalization actions. Detect this case
544 -- and complete the expansion of the allocator.
546 if Nkind
(Expr
) = N_Identifier
547 and then Nkind
(Parent
(Entity
(Expr
))) = N_Object_Declaration
548 and then Nkind
(Expression
(Parent
(Entity
(Expr
)))) = N_Allocator
550 Build_Allocate_Deallocate_Proc
(Parent
(Entity
(Expr
)), True);
554 -- The allocator may have been rewritten into something else in which
555 -- case the expansion performed by this routine does not apply.
557 if Nkind
(Expr
) /= N_Allocator
then
561 Ptr_Typ
:= Base_Type
(Etype
(Expr
));
562 Proc_To_Call
:= Procedure_To_Call
(Expr
);
565 Pool_Id
:= Associated_Storage_Pool
(Ptr_Typ
);
566 Desig_Typ
:= Available_View
(Designated_Type
(Ptr_Typ
));
568 -- Handle concurrent types
570 if Is_Concurrent_Type
(Desig_Typ
)
571 and then Present
(Corresponding_Record_Type
(Desig_Typ
))
573 Desig_Typ
:= Corresponding_Record_Type
(Desig_Typ
);
576 -- Do not process allocations / deallocations without a pool
581 -- Do not process allocations on / deallocations from the secondary
584 elsif Is_RTE
(Pool_Id
, RE_SS_Pool
) then
587 -- Do not replicate the machinery if the allocator / free has already
588 -- been expanded and has a custom Allocate / Deallocate.
590 elsif Present
(Proc_To_Call
)
591 and then Is_Allocate_Deallocate_Proc
(Proc_To_Call
)
596 if Needs_Finalization
(Desig_Typ
) then
598 -- Certain run-time configurations and targets do not provide support
599 -- for controlled types.
601 if Restriction_Active
(No_Finalization
) then
604 -- Do nothing if the access type may never allocate / deallocate
607 elsif No_Pool_Assigned
(Ptr_Typ
) then
611 -- The allocation / deallocation of a controlled object must be
612 -- chained on / detached from a finalization master.
614 pragma Assert
(Present
(Finalization_Master
(Ptr_Typ
)));
616 -- The only other kind of allocation / deallocation supported by this
617 -- routine is on / from a subpool.
619 elsif Nkind
(Expr
) = N_Allocator
620 and then No
(Subpool_Handle_Name
(Expr
))
626 Loc
: constant Source_Ptr
:= Sloc
(N
);
627 Addr_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
628 Alig_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'L');
629 Proc_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'P');
630 Size_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'S');
633 Fin_Addr_Id
: Entity_Id
;
634 Fin_Mas_Act
: Node_Id
;
635 Fin_Mas_Id
: Entity_Id
;
636 Proc_To_Call
: Entity_Id
;
637 Subpool
: Node_Id
:= Empty
;
640 -- Step 1: Construct all the actuals for the call to library routine
641 -- Allocate_Any_Controlled / Deallocate_Any_Controlled.
645 Actuals
:= New_List
(New_Occurrence_Of
(Pool_Id
, Loc
));
651 if Nkind
(Expr
) = N_Allocator
then
652 Subpool
:= Subpool_Handle_Name
(Expr
);
655 -- If a subpool is present it can be an arbitrary name, so make
656 -- the actual by copying the tree.
658 if Present
(Subpool
) then
659 Append_To
(Actuals
, New_Copy_Tree
(Subpool
, New_Sloc
=> Loc
));
661 Append_To
(Actuals
, Make_Null
(Loc
));
664 -- c) Finalization master
666 if Needs_Finalization
(Desig_Typ
) then
667 Fin_Mas_Id
:= Finalization_Master
(Ptr_Typ
);
668 Fin_Mas_Act
:= New_Occurrence_Of
(Fin_Mas_Id
, Loc
);
670 -- Handle the case where the master is actually a pointer to a
671 -- master. This case arises in build-in-place functions.
673 if Is_Access_Type
(Etype
(Fin_Mas_Id
)) then
674 Append_To
(Actuals
, Fin_Mas_Act
);
677 Make_Attribute_Reference
(Loc
,
678 Prefix
=> Fin_Mas_Act
,
679 Attribute_Name
=> Name_Unrestricted_Access
));
682 Append_To
(Actuals
, Make_Null
(Loc
));
685 -- d) Finalize_Address
687 -- Primitive Finalize_Address is never generated in CodePeer mode
688 -- since it contains an Unchecked_Conversion.
690 if Needs_Finalization
(Desig_Typ
) and then not CodePeer_Mode
then
691 Fin_Addr_Id
:= Finalize_Address
(Desig_Typ
);
692 pragma Assert
(Present
(Fin_Addr_Id
));
695 Make_Attribute_Reference
(Loc
,
696 Prefix
=> New_Occurrence_Of
(Fin_Addr_Id
, Loc
),
697 Attribute_Name
=> Name_Unrestricted_Access
));
699 Append_To
(Actuals
, Make_Null
(Loc
));
707 Append_To
(Actuals
, New_Occurrence_Of
(Addr_Id
, Loc
));
708 Append_To
(Actuals
, New_Occurrence_Of
(Size_Id
, Loc
));
710 if Is_Allocate
or else not Is_Class_Wide_Type
(Desig_Typ
) then
711 Append_To
(Actuals
, New_Occurrence_Of
(Alig_Id
, Loc
));
713 -- For deallocation of class-wide types we obtain the value of
714 -- alignment from the Type Specific Record of the deallocated object.
715 -- This is needed because the frontend expansion of class-wide types
716 -- into equivalent types confuses the backend.
722 -- ... because 'Alignment applied to class-wide types is expanded
723 -- into the code that reads the value of alignment from the TSD
724 -- (see Expand_N_Attribute_Reference)
727 Unchecked_Convert_To
(RTE
(RE_Storage_Offset
),
728 Make_Attribute_Reference
(Loc
,
730 Make_Explicit_Dereference
(Loc
, Relocate_Node
(Expr
)),
731 Attribute_Name
=> Name_Alignment
)));
736 if Needs_Finalization
(Desig_Typ
) then
738 Flag_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'F');
745 Temp
:= Find_Object
(Expression
(Expr
));
750 -- Processing for allocations where the expression is a subtype
754 and then Is_Entity_Name
(Temp
)
755 and then Is_Type
(Entity
(Temp
))
760 (Needs_Finalization
(Entity
(Temp
))), Loc
);
762 -- The allocation / deallocation of a class-wide object relies
763 -- on a runtime check to determine whether the object is truly
764 -- controlled or not. Depending on this check, the finalization
765 -- machinery will request or reclaim extra storage reserved for
768 elsif Is_Class_Wide_Type
(Desig_Typ
) then
770 -- Detect a special case where interface class-wide types
771 -- are involved as the object appears as:
773 -- Tag_Ptr (Base_Address (<object>'Address))
775 -- The expression already yields the proper tag, generate:
779 if Is_RTE
(Etype
(Temp
), RE_Tag_Ptr
) then
781 Make_Explicit_Dereference
(Loc
,
782 Prefix
=> Relocate_Node
(Temp
));
784 -- In the default case, obtain the tag of the object about
785 -- to be allocated / deallocated. Generate:
791 Make_Attribute_Reference
(Loc
,
792 Prefix
=> Relocate_Node
(Temp
),
793 Attribute_Name
=> Name_Tag
);
797 -- Needs_Finalization (<Param>)
800 Make_Function_Call
(Loc
,
802 New_Occurrence_Of
(RTE
(RE_Needs_Finalization
), Loc
),
803 Parameter_Associations
=> New_List
(Param
));
805 -- Processing for generic actuals
807 elsif Is_Generic_Actual_Type
(Desig_Typ
) then
809 New_Occurrence_Of
(Boolean_Literals
810 (Needs_Finalization
(Base_Type
(Desig_Typ
))), Loc
);
812 -- The object does not require any specialized checks, it is
813 -- known to be controlled.
816 Flag_Expr
:= New_Occurrence_Of
(Standard_True
, Loc
);
819 -- Create the temporary which represents the finalization state
820 -- of the expression. Generate:
822 -- F : constant Boolean := <Flag_Expr>;
825 Make_Object_Declaration
(Loc
,
826 Defining_Identifier
=> Flag_Id
,
827 Constant_Present
=> True,
829 New_Occurrence_Of
(Standard_Boolean
, Loc
),
830 Expression
=> Flag_Expr
));
832 Append_To
(Actuals
, New_Occurrence_Of
(Flag_Id
, Loc
));
835 -- The object is not controlled
838 Append_To
(Actuals
, New_Occurrence_Of
(Standard_False
, Loc
));
845 New_Occurrence_Of
(Boolean_Literals
(Present
(Subpool
)), Loc
));
848 -- Step 2: Build a wrapper Allocate / Deallocate which internally
849 -- calls Allocate_Any_Controlled / Deallocate_Any_Controlled.
851 -- Select the proper routine to call
854 Proc_To_Call
:= RTE
(RE_Allocate_Any_Controlled
);
856 Proc_To_Call
:= RTE
(RE_Deallocate_Any_Controlled
);
859 -- Create a custom Allocate / Deallocate routine which has identical
860 -- profile to that of System.Storage_Pools.
863 Make_Subprogram_Body
(Loc
,
868 Make_Procedure_Specification
(Loc
,
869 Defining_Unit_Name
=> Proc_Id
,
870 Parameter_Specifications
=> New_List
(
872 -- P : Root_Storage_Pool
874 Make_Parameter_Specification
(Loc
,
875 Defining_Identifier
=> Make_Temporary
(Loc
, 'P'),
877 New_Occurrence_Of
(RTE
(RE_Root_Storage_Pool
), Loc
)),
881 Make_Parameter_Specification
(Loc
,
882 Defining_Identifier
=> Addr_Id
,
883 Out_Present
=> Is_Allocate
,
885 New_Occurrence_Of
(RTE
(RE_Address
), Loc
)),
889 Make_Parameter_Specification
(Loc
,
890 Defining_Identifier
=> Size_Id
,
892 New_Occurrence_Of
(RTE
(RE_Storage_Count
), Loc
)),
896 Make_Parameter_Specification
(Loc
,
897 Defining_Identifier
=> Alig_Id
,
899 New_Occurrence_Of
(RTE
(RE_Storage_Count
), Loc
)))),
901 Declarations
=> No_List
,
903 Handled_Statement_Sequence
=>
904 Make_Handled_Sequence_Of_Statements
(Loc
,
905 Statements
=> New_List
(
906 Make_Procedure_Call_Statement
(Loc
,
907 Name
=> New_Occurrence_Of
(Proc_To_Call
, Loc
),
908 Parameter_Associations
=> Actuals
)))));
910 -- The newly generated Allocate / Deallocate becomes the default
911 -- procedure to call when the back end processes the allocation /
915 Set_Procedure_To_Call
(Expr
, Proc_Id
);
917 Set_Procedure_To_Call
(N
, Proc_Id
);
920 end Build_Allocate_Deallocate_Proc
;
922 --------------------------
923 -- Build_Procedure_Form --
924 --------------------------
926 procedure Build_Procedure_Form
(N
: Node_Id
) is
927 Loc
: constant Source_Ptr
:= Sloc
(N
);
928 Subp
: constant Entity_Id
:= Defining_Entity
(N
);
930 Func_Formal
: Entity_Id
;
931 Proc_Formals
: List_Id
;
935 -- No action needed if this transformation was already done, or in case
936 -- of subprogram renaming declarations.
938 if Nkind
(Specification
(N
)) = N_Procedure_Specification
939 or else Nkind
(N
) = N_Subprogram_Renaming_Declaration
944 -- Ditto when dealing with an expression function, where both the
945 -- original expression and the generated declaration end up being
948 if Rewritten_For_C
(Subp
) then
952 Proc_Formals
:= New_List
;
954 -- Create a list of formal parameters with the same types as the
957 Func_Formal
:= First_Formal
(Subp
);
958 while Present
(Func_Formal
) loop
959 Append_To
(Proc_Formals
,
960 Make_Parameter_Specification
(Loc
,
961 Defining_Identifier
=>
962 Make_Defining_Identifier
(Loc
, Chars
(Func_Formal
)),
964 New_Occurrence_Of
(Etype
(Func_Formal
), Loc
)));
966 Next_Formal
(Func_Formal
);
969 -- Add an extra out parameter to carry the function result
972 Name_Buffer
(1 .. Name_Len
) := "RESULT";
973 Append_To
(Proc_Formals
,
974 Make_Parameter_Specification
(Loc
,
975 Defining_Identifier
=>
976 Make_Defining_Identifier
(Loc
, Chars
=> Name_Find
),
978 Parameter_Type
=> New_Occurrence_Of
(Etype
(Subp
), Loc
)));
980 -- The new procedure declaration is inserted immediately after the
981 -- function declaration. The processing in Build_Procedure_Body_Form
982 -- relies on this order.
985 Make_Subprogram_Declaration
(Loc
,
987 Make_Procedure_Specification
(Loc
,
988 Defining_Unit_Name
=>
989 Make_Defining_Identifier
(Loc
, Chars
(Subp
)),
990 Parameter_Specifications
=> Proc_Formals
));
992 Insert_After_And_Analyze
(Unit_Declaration_Node
(Subp
), Proc_Decl
);
994 -- Entity of procedure must remain invisible so that it does not
995 -- overload subsequent references to the original function.
997 Set_Is_Immediately_Visible
(Defining_Entity
(Proc_Decl
), False);
999 -- Mark the function as having a procedure form and link the function
1000 -- and its internally built procedure.
1002 Set_Rewritten_For_C
(Subp
);
1003 Set_Corresponding_Procedure
(Subp
, Defining_Entity
(Proc_Decl
));
1004 Set_Corresponding_Function
(Defining_Entity
(Proc_Decl
), Subp
);
1005 end Build_Procedure_Form
;
1007 ------------------------
1008 -- Build_Runtime_Call --
1009 ------------------------
1011 function Build_Runtime_Call
(Loc
: Source_Ptr
; RE
: RE_Id
) return Node_Id
is
1013 -- If entity is not available, we can skip making the call (this avoids
1014 -- junk duplicated error messages in a number of cases).
1016 if not RTE_Available
(RE
) then
1017 return Make_Null_Statement
(Loc
);
1020 Make_Procedure_Call_Statement
(Loc
,
1021 Name
=> New_Occurrence_Of
(RTE
(RE
), Loc
));
1023 end Build_Runtime_Call
;
1025 ------------------------
1026 -- Build_SS_Mark_Call --
1027 ------------------------
1029 function Build_SS_Mark_Call
1031 Mark
: Entity_Id
) return Node_Id
1035 -- Mark : constant Mark_Id := SS_Mark;
1038 Make_Object_Declaration
(Loc
,
1039 Defining_Identifier
=> Mark
,
1040 Constant_Present
=> True,
1041 Object_Definition
=>
1042 New_Occurrence_Of
(RTE
(RE_Mark_Id
), Loc
),
1044 Make_Function_Call
(Loc
,
1045 Name
=> New_Occurrence_Of
(RTE
(RE_SS_Mark
), Loc
)));
1046 end Build_SS_Mark_Call
;
1048 ---------------------------
1049 -- Build_SS_Release_Call --
1050 ---------------------------
1052 function Build_SS_Release_Call
1054 Mark
: Entity_Id
) return Node_Id
1058 -- SS_Release (Mark);
1061 Make_Procedure_Call_Statement
(Loc
,
1063 New_Occurrence_Of
(RTE
(RE_SS_Release
), Loc
),
1064 Parameter_Associations
=> New_List
(
1065 New_Occurrence_Of
(Mark
, Loc
)));
1066 end Build_SS_Release_Call
;
1068 ----------------------------
1069 -- Build_Task_Array_Image --
1070 ----------------------------
1072 -- This function generates the body for a function that constructs the
1073 -- image string for a task that is an array component. The function is
1074 -- local to the init proc for the array type, and is called for each one
1075 -- of the components. The constructed image has the form of an indexed
1076 -- component, whose prefix is the outer variable of the array type.
1077 -- The n-dimensional array type has known indexes Index, Index2...
1079 -- Id_Ref is an indexed component form created by the enclosing init proc.
1080 -- Its successive indexes are Val1, Val2, ... which are the loop variables
1081 -- in the loops that call the individual task init proc on each component.
1083 -- The generated function has the following structure:
1085 -- function F return String is
1086 -- Pref : string renames Task_Name;
1087 -- T1 : String := Index1'Image (Val1);
1089 -- Tn : String := indexn'image (Valn);
1090 -- Len : Integer := T1'Length + ... + Tn'Length + n + 1;
1091 -- -- Len includes commas and the end parentheses.
1092 -- Res : String (1..Len);
1093 -- Pos : Integer := Pref'Length;
1096 -- Res (1 .. Pos) := Pref;
1098 -- Res (Pos) := '(';
1100 -- Res (Pos .. Pos + T1'Length - 1) := T1;
1101 -- Pos := Pos + T1'Length;
1102 -- Res (Pos) := '.';
1105 -- Res (Pos .. Pos + Tn'Length - 1) := Tn;
1106 -- Res (Len) := ')';
1111 -- Needless to say, multidimensional arrays of tasks are rare enough that
1112 -- the bulkiness of this code is not really a concern.
1114 function Build_Task_Array_Image
1118 Dyn
: Boolean := False) return Node_Id
1120 Dims
: constant Nat
:= Number_Dimensions
(A_Type
);
1121 -- Number of dimensions for array of tasks
1123 Temps
: array (1 .. Dims
) of Entity_Id
;
1124 -- Array of temporaries to hold string for each index
1130 -- Total length of generated name
1133 -- Running index for substring assignments
1135 Pref
: constant Entity_Id
:= Make_Temporary
(Loc
, 'P');
1136 -- Name of enclosing variable, prefix of resulting name
1139 -- String to hold result
1142 -- Value of successive indexes
1145 -- Expression to compute total size of string
1148 -- Entity for name at one index position
1150 Decls
: constant List_Id
:= New_List
;
1151 Stats
: constant List_Id
:= New_List
;
1154 -- For a dynamic task, the name comes from the target variable. For a
1155 -- static one it is a formal of the enclosing init proc.
1158 Get_Name_String
(Chars
(Entity
(Prefix
(Id_Ref
))));
1160 Make_Object_Declaration
(Loc
,
1161 Defining_Identifier
=> Pref
,
1162 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1164 Make_String_Literal
(Loc
,
1165 Strval
=> String_From_Name_Buffer
)));
1169 Make_Object_Renaming_Declaration
(Loc
,
1170 Defining_Identifier
=> Pref
,
1171 Subtype_Mark
=> New_Occurrence_Of
(Standard_String
, Loc
),
1172 Name
=> Make_Identifier
(Loc
, Name_uTask_Name
)));
1175 Indx
:= First_Index
(A_Type
);
1176 Val
:= First
(Expressions
(Id_Ref
));
1178 for J
in 1 .. Dims
loop
1179 T
:= Make_Temporary
(Loc
, 'T');
1183 Make_Object_Declaration
(Loc
,
1184 Defining_Identifier
=> T
,
1185 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1187 Make_Attribute_Reference
(Loc
,
1188 Attribute_Name
=> Name_Image
,
1189 Prefix
=> New_Occurrence_Of
(Etype
(Indx
), Loc
),
1190 Expressions
=> New_List
(New_Copy_Tree
(Val
)))));
1196 Sum
:= Make_Integer_Literal
(Loc
, Dims
+ 1);
1202 Make_Attribute_Reference
(Loc
,
1203 Attribute_Name
=> Name_Length
,
1204 Prefix
=> New_Occurrence_Of
(Pref
, Loc
),
1205 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1))));
1207 for J
in 1 .. Dims
loop
1212 Make_Attribute_Reference
(Loc
,
1213 Attribute_Name
=> Name_Length
,
1215 New_Occurrence_Of
(Temps
(J
), Loc
),
1216 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1))));
1219 Build_Task_Image_Prefix
(Loc
, Len
, Res
, Pos
, Pref
, Sum
, Decls
, Stats
);
1221 Set_Character_Literal_Name
(Char_Code
(Character'Pos ('(')));
1224 Make_Assignment_Statement
(Loc
,
1226 Make_Indexed_Component
(Loc
,
1227 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1228 Expressions
=> New_List
(New_Occurrence_Of
(Pos
, Loc
))),
1230 Make_Character_Literal
(Loc
,
1232 Char_Literal_Value
=> UI_From_Int
(Character'Pos ('(')))));
1235 Make_Assignment_Statement
(Loc
,
1236 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1239 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1240 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1242 for J
in 1 .. Dims
loop
1245 Make_Assignment_Statement
(Loc
,
1248 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1251 Low_Bound
=> New_Occurrence_Of
(Pos
, Loc
),
1253 Make_Op_Subtract
(Loc
,
1256 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1258 Make_Attribute_Reference
(Loc
,
1259 Attribute_Name
=> Name_Length
,
1261 New_Occurrence_Of
(Temps
(J
), Loc
),
1263 New_List
(Make_Integer_Literal
(Loc
, 1)))),
1264 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1)))),
1266 Expression
=> New_Occurrence_Of
(Temps
(J
), Loc
)));
1270 Make_Assignment_Statement
(Loc
,
1271 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1274 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1276 Make_Attribute_Reference
(Loc
,
1277 Attribute_Name
=> Name_Length
,
1278 Prefix
=> New_Occurrence_Of
(Temps
(J
), Loc
),
1280 New_List
(Make_Integer_Literal
(Loc
, 1))))));
1282 Set_Character_Literal_Name
(Char_Code
(Character'Pos (',')));
1285 Make_Assignment_Statement
(Loc
,
1286 Name
=> Make_Indexed_Component
(Loc
,
1287 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1288 Expressions
=> New_List
(New_Occurrence_Of
(Pos
, Loc
))),
1290 Make_Character_Literal
(Loc
,
1292 Char_Literal_Value
=> UI_From_Int
(Character'Pos (',')))));
1295 Make_Assignment_Statement
(Loc
,
1296 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1299 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1300 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1304 Set_Character_Literal_Name
(Char_Code
(Character'Pos (')')));
1307 Make_Assignment_Statement
(Loc
,
1309 Make_Indexed_Component
(Loc
,
1310 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1311 Expressions
=> New_List
(New_Occurrence_Of
(Len
, Loc
))),
1313 Make_Character_Literal
(Loc
,
1315 Char_Literal_Value
=> UI_From_Int
(Character'Pos (')')))));
1316 return Build_Task_Image_Function
(Loc
, Decls
, Stats
, Res
);
1317 end Build_Task_Array_Image
;
1319 ----------------------------
1320 -- Build_Task_Image_Decls --
1321 ----------------------------
1323 function Build_Task_Image_Decls
1327 In_Init_Proc
: Boolean := False) return List_Id
1329 Decls
: constant List_Id
:= New_List
;
1330 T_Id
: Entity_Id
:= Empty
;
1332 Expr
: Node_Id
:= Empty
;
1333 Fun
: Node_Id
:= Empty
;
1334 Is_Dyn
: constant Boolean :=
1335 Nkind
(Parent
(Id_Ref
)) = N_Assignment_Statement
1337 Nkind
(Expression
(Parent
(Id_Ref
))) = N_Allocator
;
1340 -- If Discard_Names or No_Implicit_Heap_Allocations are in effect,
1341 -- generate a dummy declaration only.
1343 if Restriction_Active
(No_Implicit_Heap_Allocations
)
1344 or else Global_Discard_Names
1346 T_Id
:= Make_Temporary
(Loc
, 'J');
1351 Make_Object_Declaration
(Loc
,
1352 Defining_Identifier
=> T_Id
,
1353 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1355 Make_String_Literal
(Loc
,
1356 Strval
=> String_From_Name_Buffer
)));
1359 if Nkind
(Id_Ref
) = N_Identifier
1360 or else Nkind
(Id_Ref
) = N_Defining_Identifier
1362 -- For a simple variable, the image of the task is built from
1363 -- the name of the variable. To avoid possible conflict with the
1364 -- anonymous type created for a single protected object, add a
1368 Make_Defining_Identifier
(Loc
,
1369 New_External_Name
(Chars
(Id_Ref
), 'T', 1));
1371 Get_Name_String
(Chars
(Id_Ref
));
1374 Make_String_Literal
(Loc
,
1375 Strval
=> String_From_Name_Buffer
);
1377 elsif Nkind
(Id_Ref
) = N_Selected_Component
then
1379 Make_Defining_Identifier
(Loc
,
1380 New_External_Name
(Chars
(Selector_Name
(Id_Ref
)), 'T'));
1381 Fun
:= Build_Task_Record_Image
(Loc
, Id_Ref
, Is_Dyn
);
1383 elsif Nkind
(Id_Ref
) = N_Indexed_Component
then
1385 Make_Defining_Identifier
(Loc
,
1386 New_External_Name
(Chars
(A_Type
), 'N'));
1388 Fun
:= Build_Task_Array_Image
(Loc
, Id_Ref
, A_Type
, Is_Dyn
);
1392 if Present
(Fun
) then
1393 Append
(Fun
, Decls
);
1394 Expr
:= Make_Function_Call
(Loc
,
1395 Name
=> New_Occurrence_Of
(Defining_Entity
(Fun
), Loc
));
1397 if not In_Init_Proc
then
1398 Set_Uses_Sec_Stack
(Defining_Entity
(Fun
));
1402 Decl
:= Make_Object_Declaration
(Loc
,
1403 Defining_Identifier
=> T_Id
,
1404 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1405 Constant_Present
=> True,
1406 Expression
=> Expr
);
1408 Append
(Decl
, Decls
);
1410 end Build_Task_Image_Decls
;
1412 -------------------------------
1413 -- Build_Task_Image_Function --
1414 -------------------------------
1416 function Build_Task_Image_Function
1420 Res
: Entity_Id
) return Node_Id
1426 Make_Simple_Return_Statement
(Loc
,
1427 Expression
=> New_Occurrence_Of
(Res
, Loc
)));
1429 Spec
:= Make_Function_Specification
(Loc
,
1430 Defining_Unit_Name
=> Make_Temporary
(Loc
, 'F'),
1431 Result_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
));
1433 -- Calls to 'Image use the secondary stack, which must be cleaned up
1434 -- after the task name is built.
1436 return Make_Subprogram_Body
(Loc
,
1437 Specification
=> Spec
,
1438 Declarations
=> Decls
,
1439 Handled_Statement_Sequence
=>
1440 Make_Handled_Sequence_Of_Statements
(Loc
, Statements
=> Stats
));
1441 end Build_Task_Image_Function
;
1443 -----------------------------
1444 -- Build_Task_Image_Prefix --
1445 -----------------------------
1447 procedure Build_Task_Image_Prefix
1449 Len
: out Entity_Id
;
1450 Res
: out Entity_Id
;
1451 Pos
: out Entity_Id
;
1458 Len
:= Make_Temporary
(Loc
, 'L', Sum
);
1461 Make_Object_Declaration
(Loc
,
1462 Defining_Identifier
=> Len
,
1463 Object_Definition
=> New_Occurrence_Of
(Standard_Integer
, Loc
),
1464 Expression
=> Sum
));
1466 Res
:= Make_Temporary
(Loc
, 'R');
1469 Make_Object_Declaration
(Loc
,
1470 Defining_Identifier
=> Res
,
1471 Object_Definition
=>
1472 Make_Subtype_Indication
(Loc
,
1473 Subtype_Mark
=> New_Occurrence_Of
(Standard_String
, Loc
),
1475 Make_Index_Or_Discriminant_Constraint
(Loc
,
1479 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
1480 High_Bound
=> New_Occurrence_Of
(Len
, Loc
)))))));
1482 -- Indicate that the result is an internal temporary, so it does not
1483 -- receive a bogus initialization when declaration is expanded. This
1484 -- is both efficient, and prevents anomalies in the handling of
1485 -- dynamic objects on the secondary stack.
1487 Set_Is_Internal
(Res
);
1488 Pos
:= Make_Temporary
(Loc
, 'P');
1491 Make_Object_Declaration
(Loc
,
1492 Defining_Identifier
=> Pos
,
1493 Object_Definition
=> New_Occurrence_Of
(Standard_Integer
, Loc
)));
1495 -- Pos := Prefix'Length;
1498 Make_Assignment_Statement
(Loc
,
1499 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1501 Make_Attribute_Reference
(Loc
,
1502 Attribute_Name
=> Name_Length
,
1503 Prefix
=> New_Occurrence_Of
(Prefix
, Loc
),
1504 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1)))));
1506 -- Res (1 .. Pos) := Prefix;
1509 Make_Assignment_Statement
(Loc
,
1512 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1515 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
1516 High_Bound
=> New_Occurrence_Of
(Pos
, Loc
))),
1518 Expression
=> New_Occurrence_Of
(Prefix
, Loc
)));
1521 Make_Assignment_Statement
(Loc
,
1522 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1525 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1526 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1527 end Build_Task_Image_Prefix
;
1529 -----------------------------
1530 -- Build_Task_Record_Image --
1531 -----------------------------
1533 function Build_Task_Record_Image
1536 Dyn
: Boolean := False) return Node_Id
1539 -- Total length of generated name
1542 -- Index into result
1545 -- String to hold result
1547 Pref
: constant Entity_Id
:= Make_Temporary
(Loc
, 'P');
1548 -- Name of enclosing variable, prefix of resulting name
1551 -- Expression to compute total size of string
1554 -- Entity for selector name
1556 Decls
: constant List_Id
:= New_List
;
1557 Stats
: constant List_Id
:= New_List
;
1560 -- For a dynamic task, the name comes from the target variable. For a
1561 -- static one it is a formal of the enclosing init proc.
1564 Get_Name_String
(Chars
(Entity
(Prefix
(Id_Ref
))));
1566 Make_Object_Declaration
(Loc
,
1567 Defining_Identifier
=> Pref
,
1568 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1570 Make_String_Literal
(Loc
,
1571 Strval
=> String_From_Name_Buffer
)));
1575 Make_Object_Renaming_Declaration
(Loc
,
1576 Defining_Identifier
=> Pref
,
1577 Subtype_Mark
=> New_Occurrence_Of
(Standard_String
, Loc
),
1578 Name
=> Make_Identifier
(Loc
, Name_uTask_Name
)));
1581 Sel
:= Make_Temporary
(Loc
, 'S');
1583 Get_Name_String
(Chars
(Selector_Name
(Id_Ref
)));
1586 Make_Object_Declaration
(Loc
,
1587 Defining_Identifier
=> Sel
,
1588 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1590 Make_String_Literal
(Loc
,
1591 Strval
=> String_From_Name_Buffer
)));
1593 Sum
:= Make_Integer_Literal
(Loc
, Nat
(Name_Len
+ 1));
1599 Make_Attribute_Reference
(Loc
,
1600 Attribute_Name
=> Name_Length
,
1602 New_Occurrence_Of
(Pref
, Loc
),
1603 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1))));
1605 Build_Task_Image_Prefix
(Loc
, Len
, Res
, Pos
, Pref
, Sum
, Decls
, Stats
);
1607 Set_Character_Literal_Name
(Char_Code
(Character'Pos ('.')));
1609 -- Res (Pos) := '.';
1612 Make_Assignment_Statement
(Loc
,
1613 Name
=> Make_Indexed_Component
(Loc
,
1614 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1615 Expressions
=> New_List
(New_Occurrence_Of
(Pos
, Loc
))),
1617 Make_Character_Literal
(Loc
,
1619 Char_Literal_Value
=>
1620 UI_From_Int
(Character'Pos ('.')))));
1623 Make_Assignment_Statement
(Loc
,
1624 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1627 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1628 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1630 -- Res (Pos .. Len) := Selector;
1633 Make_Assignment_Statement
(Loc
,
1634 Name
=> Make_Slice
(Loc
,
1635 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1638 Low_Bound
=> New_Occurrence_Of
(Pos
, Loc
),
1639 High_Bound
=> New_Occurrence_Of
(Len
, Loc
))),
1640 Expression
=> New_Occurrence_Of
(Sel
, Loc
)));
1642 return Build_Task_Image_Function
(Loc
, Decls
, Stats
, Res
);
1643 end Build_Task_Record_Image
;
1645 -----------------------------
1646 -- Check_Float_Op_Overflow --
1647 -----------------------------
1649 procedure Check_Float_Op_Overflow
(N
: Node_Id
) is
1651 -- Return if no check needed
1653 if not Is_Floating_Point_Type
(Etype
(N
))
1654 or else not (Do_Overflow_Check
(N
) and then Check_Float_Overflow
)
1656 -- In CodePeer_Mode, rely on the overflow check flag being set instead
1657 -- and do not expand the code for float overflow checking.
1659 or else CodePeer_Mode
1664 -- Otherwise we replace the expression by
1666 -- do Tnn : constant ftype := expression;
1667 -- constraint_error when not Tnn'Valid;
1671 Loc
: constant Source_Ptr
:= Sloc
(N
);
1672 Tnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T', N
);
1673 Typ
: constant Entity_Id
:= Etype
(N
);
1676 -- Turn off the Do_Overflow_Check flag, since we are doing that work
1677 -- right here. We also set the node as analyzed to prevent infinite
1678 -- recursion from repeating the operation in the expansion.
1680 Set_Do_Overflow_Check
(N
, False);
1681 Set_Analyzed
(N
, True);
1683 -- Do the rewrite to include the check
1686 Make_Expression_With_Actions
(Loc
,
1687 Actions
=> New_List
(
1688 Make_Object_Declaration
(Loc
,
1689 Defining_Identifier
=> Tnn
,
1690 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
),
1691 Constant_Present
=> True,
1692 Expression
=> Relocate_Node
(N
)),
1693 Make_Raise_Constraint_Error
(Loc
,
1697 Make_Attribute_Reference
(Loc
,
1698 Prefix
=> New_Occurrence_Of
(Tnn
, Loc
),
1699 Attribute_Name
=> Name_Valid
)),
1700 Reason
=> CE_Overflow_Check_Failed
)),
1701 Expression
=> New_Occurrence_Of
(Tnn
, Loc
)));
1703 Analyze_And_Resolve
(N
, Typ
);
1705 end Check_Float_Op_Overflow
;
1707 ----------------------------------
1708 -- Component_May_Be_Bit_Aligned --
1709 ----------------------------------
1711 function Component_May_Be_Bit_Aligned
(Comp
: Entity_Id
) return Boolean is
1715 -- If no component clause, then everything is fine, since the back end
1716 -- never bit-misaligns by default, even if there is a pragma Packed for
1719 if No
(Comp
) or else No
(Component_Clause
(Comp
)) then
1723 UT
:= Underlying_Type
(Etype
(Comp
));
1725 -- It is only array and record types that cause trouble
1727 if not Is_Record_Type
(UT
) and then not Is_Array_Type
(UT
) then
1730 -- If we know that we have a small (64 bits or less) record or small
1731 -- bit-packed array, then everything is fine, since the back end can
1732 -- handle these cases correctly.
1734 elsif Esize
(Comp
) <= 64
1735 and then (Is_Record_Type
(UT
) or else Is_Bit_Packed_Array
(UT
))
1739 -- Otherwise if the component is not byte aligned, we know we have the
1740 -- nasty unaligned case.
1742 elsif Normalized_First_Bit
(Comp
) /= Uint_0
1743 or else Esize
(Comp
) mod System_Storage_Unit
/= Uint_0
1747 -- If we are large and byte aligned, then OK at this level
1752 end Component_May_Be_Bit_Aligned
;
1754 ----------------------------------------
1755 -- Containing_Package_With_Ext_Axioms --
1756 ----------------------------------------
1758 function Containing_Package_With_Ext_Axioms
1759 (E
: Entity_Id
) return Entity_Id
1762 -- E is the package or generic package which is externally axiomatized
1764 if Ekind_In
(E
, E_Generic_Package
, E_Package
)
1765 and then Has_Annotate_Pragma_For_External_Axiomatization
(E
)
1770 -- If E's scope is axiomatized, E is axiomatized
1772 if Present
(Scope
(E
)) then
1774 First_Ax_Parent_Scope
: constant Entity_Id
:=
1775 Containing_Package_With_Ext_Axioms
(Scope
(E
));
1777 if Present
(First_Ax_Parent_Scope
) then
1778 return First_Ax_Parent_Scope
;
1783 -- Otherwise, if E is a package instance, it is axiomatized if the
1784 -- corresponding generic package is axiomatized.
1786 if Ekind
(E
) = E_Package
then
1788 Par
: constant Node_Id
:= Parent
(E
);
1792 if Nkind
(Par
) = N_Defining_Program_Unit_Name
then
1793 Decl
:= Parent
(Par
);
1798 if Present
(Generic_Parent
(Decl
)) then
1800 Containing_Package_With_Ext_Axioms
(Generic_Parent
(Decl
));
1806 end Containing_Package_With_Ext_Axioms
;
1808 -------------------------------
1809 -- Convert_To_Actual_Subtype --
1810 -------------------------------
1812 procedure Convert_To_Actual_Subtype
(Exp
: Entity_Id
) is
1816 Act_ST
:= Get_Actual_Subtype
(Exp
);
1818 if Act_ST
= Etype
(Exp
) then
1821 Rewrite
(Exp
, Convert_To
(Act_ST
, Relocate_Node
(Exp
)));
1822 Analyze_And_Resolve
(Exp
, Act_ST
);
1824 end Convert_To_Actual_Subtype
;
1826 -----------------------------------
1827 -- Corresponding_Runtime_Package --
1828 -----------------------------------
1830 function Corresponding_Runtime_Package
(Typ
: Entity_Id
) return RTU_Id
is
1831 Pkg_Id
: RTU_Id
:= RTU_Null
;
1834 pragma Assert
(Is_Concurrent_Type
(Typ
));
1836 if Ekind
(Typ
) in Protected_Kind
then
1837 if Has_Entries
(Typ
)
1839 -- A protected type without entries that covers an interface and
1840 -- overrides the abstract routines with protected procedures is
1841 -- considered equivalent to a protected type with entries in the
1842 -- context of dispatching select statements. It is sufficient to
1843 -- check for the presence of an interface list in the declaration
1844 -- node to recognize this case.
1846 or else Present
(Interface_List
(Parent
(Typ
)))
1848 -- Protected types with interrupt handlers (when not using a
1849 -- restricted profile) are also considered equivalent to
1850 -- protected types with entries. The types which are used
1851 -- (Static_Interrupt_Protection and Dynamic_Interrupt_Protection)
1852 -- are derived from Protection_Entries.
1854 or else (Has_Attach_Handler
(Typ
) and then not Restricted_Profile
)
1855 or else Has_Interrupt_Handler
(Typ
)
1858 or else Restriction_Active
(No_Entry_Queue
) = False
1859 or else Restriction_Active
(No_Select_Statements
) = False
1860 or else Number_Entries
(Typ
) > 1
1861 or else (Has_Attach_Handler
(Typ
)
1862 and then not Restricted_Profile
)
1864 Pkg_Id
:= System_Tasking_Protected_Objects_Entries
;
1866 Pkg_Id
:= System_Tasking_Protected_Objects_Single_Entry
;
1870 Pkg_Id
:= System_Tasking_Protected_Objects
;
1875 end Corresponding_Runtime_Package
;
1877 -----------------------------------
1878 -- Current_Sem_Unit_Declarations --
1879 -----------------------------------
1881 function Current_Sem_Unit_Declarations
return List_Id
is
1882 U
: Node_Id
:= Unit
(Cunit
(Current_Sem_Unit
));
1886 -- If the current unit is a package body, locate the visible
1887 -- declarations of the package spec.
1889 if Nkind
(U
) = N_Package_Body
then
1890 U
:= Unit
(Library_Unit
(Cunit
(Current_Sem_Unit
)));
1893 if Nkind
(U
) = N_Package_Declaration
then
1894 U
:= Specification
(U
);
1895 Decls
:= Visible_Declarations
(U
);
1899 Set_Visible_Declarations
(U
, Decls
);
1903 Decls
:= Declarations
(U
);
1907 Set_Declarations
(U
, Decls
);
1912 end Current_Sem_Unit_Declarations
;
1914 -----------------------
1915 -- Duplicate_Subexpr --
1916 -----------------------
1918 function Duplicate_Subexpr
1920 Name_Req
: Boolean := False;
1921 Renaming_Req
: Boolean := False) return Node_Id
1924 Remove_Side_Effects
(Exp
, Name_Req
, Renaming_Req
);
1925 return New_Copy_Tree
(Exp
);
1926 end Duplicate_Subexpr
;
1928 ---------------------------------
1929 -- Duplicate_Subexpr_No_Checks --
1930 ---------------------------------
1932 function Duplicate_Subexpr_No_Checks
1934 Name_Req
: Boolean := False;
1935 Renaming_Req
: Boolean := False;
1936 Related_Id
: Entity_Id
:= Empty
;
1937 Is_Low_Bound
: Boolean := False;
1938 Is_High_Bound
: Boolean := False) return Node_Id
1945 Name_Req
=> Name_Req
,
1946 Renaming_Req
=> Renaming_Req
,
1947 Related_Id
=> Related_Id
,
1948 Is_Low_Bound
=> Is_Low_Bound
,
1949 Is_High_Bound
=> Is_High_Bound
);
1951 New_Exp
:= New_Copy_Tree
(Exp
);
1952 Remove_Checks
(New_Exp
);
1954 end Duplicate_Subexpr_No_Checks
;
1956 -----------------------------------
1957 -- Duplicate_Subexpr_Move_Checks --
1958 -----------------------------------
1960 function Duplicate_Subexpr_Move_Checks
1962 Name_Req
: Boolean := False;
1963 Renaming_Req
: Boolean := False) return Node_Id
1968 Remove_Side_Effects
(Exp
, Name_Req
, Renaming_Req
);
1969 New_Exp
:= New_Copy_Tree
(Exp
);
1970 Remove_Checks
(Exp
);
1972 end Duplicate_Subexpr_Move_Checks
;
1974 --------------------
1975 -- Ensure_Defined --
1976 --------------------
1978 procedure Ensure_Defined
(Typ
: Entity_Id
; N
: Node_Id
) is
1982 -- An itype reference must only be created if this is a local itype, so
1983 -- that gigi can elaborate it on the proper objstack.
1985 if Is_Itype
(Typ
) and then Scope
(Typ
) = Current_Scope
then
1986 IR
:= Make_Itype_Reference
(Sloc
(N
));
1987 Set_Itype
(IR
, Typ
);
1988 Insert_Action
(N
, IR
);
1992 --------------------
1993 -- Entry_Names_OK --
1994 --------------------
1996 function Entry_Names_OK
return Boolean is
1999 not Restricted_Profile
2000 and then not Global_Discard_Names
2001 and then not Restriction_Active
(No_Implicit_Heap_Allocations
)
2002 and then not Restriction_Active
(No_Local_Allocators
);
2009 procedure Evaluate_Name
(Nam
: Node_Id
) is
2010 K
: constant Node_Kind
:= Nkind
(Nam
);
2013 -- For an explicit dereference, we simply force the evaluation of the
2014 -- name expression. The dereference provides a value that is the address
2015 -- for the renamed object, and it is precisely this value that we want
2018 if K
= N_Explicit_Dereference
then
2019 Force_Evaluation
(Prefix
(Nam
));
2021 -- For a selected component, we simply evaluate the prefix
2023 elsif K
= N_Selected_Component
then
2024 Evaluate_Name
(Prefix
(Nam
));
2026 -- For an indexed component, or an attribute reference, we evaluate the
2027 -- prefix, which is itself a name, recursively, and then force the
2028 -- evaluation of all the subscripts (or attribute expressions).
2030 elsif Nkind_In
(K
, N_Indexed_Component
, N_Attribute_Reference
) then
2031 Evaluate_Name
(Prefix
(Nam
));
2037 E
:= First
(Expressions
(Nam
));
2038 while Present
(E
) loop
2039 Force_Evaluation
(E
);
2041 if Original_Node
(E
) /= E
then
2042 Set_Do_Range_Check
(E
, Do_Range_Check
(Original_Node
(E
)));
2049 -- For a slice, we evaluate the prefix, as for the indexed component
2050 -- case and then, if there is a range present, either directly or as the
2051 -- constraint of a discrete subtype indication, we evaluate the two
2052 -- bounds of this range.
2054 elsif K
= N_Slice
then
2055 Evaluate_Name
(Prefix
(Nam
));
2056 Evaluate_Slice_Bounds
(Nam
);
2058 -- For a type conversion, the expression of the conversion must be the
2059 -- name of an object, and we simply need to evaluate this name.
2061 elsif K
= N_Type_Conversion
then
2062 Evaluate_Name
(Expression
(Nam
));
2064 -- For a function call, we evaluate the call
2066 elsif K
= N_Function_Call
then
2067 Force_Evaluation
(Nam
);
2069 -- The remaining cases are direct name, operator symbol and character
2070 -- literal. In all these cases, we do nothing, since we want to
2071 -- reevaluate each time the renamed object is used.
2078 ---------------------------
2079 -- Evaluate_Slice_Bounds --
2080 ---------------------------
2082 procedure Evaluate_Slice_Bounds
(Slice
: Node_Id
) is
2083 DR
: constant Node_Id
:= Discrete_Range
(Slice
);
2088 if Nkind
(DR
) = N_Range
then
2089 Force_Evaluation
(Low_Bound
(DR
));
2090 Force_Evaluation
(High_Bound
(DR
));
2092 elsif Nkind
(DR
) = N_Subtype_Indication
then
2093 Constr
:= Constraint
(DR
);
2095 if Nkind
(Constr
) = N_Range_Constraint
then
2096 Rexpr
:= Range_Expression
(Constr
);
2098 Force_Evaluation
(Low_Bound
(Rexpr
));
2099 Force_Evaluation
(High_Bound
(Rexpr
));
2102 end Evaluate_Slice_Bounds
;
2104 ---------------------
2105 -- Evolve_And_Then --
2106 ---------------------
2108 procedure Evolve_And_Then
(Cond
: in out Node_Id
; Cond1
: Node_Id
) is
2114 Make_And_Then
(Sloc
(Cond1
),
2116 Right_Opnd
=> Cond1
);
2118 end Evolve_And_Then
;
2120 --------------------
2121 -- Evolve_Or_Else --
2122 --------------------
2124 procedure Evolve_Or_Else
(Cond
: in out Node_Id
; Cond1
: Node_Id
) is
2130 Make_Or_Else
(Sloc
(Cond1
),
2132 Right_Opnd
=> Cond1
);
2136 -----------------------------------------
2137 -- Expand_Static_Predicates_In_Choices --
2138 -----------------------------------------
2140 procedure Expand_Static_Predicates_In_Choices
(N
: Node_Id
) is
2141 pragma Assert
(Nkind_In
(N
, N_Case_Statement_Alternative
, N_Variant
));
2143 Choices
: constant List_Id
:= Discrete_Choices
(N
);
2151 Choice
:= First
(Choices
);
2152 while Present
(Choice
) loop
2153 Next_C
:= Next
(Choice
);
2155 -- Check for name of subtype with static predicate
2157 if Is_Entity_Name
(Choice
)
2158 and then Is_Type
(Entity
(Choice
))
2159 and then Has_Predicates
(Entity
(Choice
))
2161 -- Loop through entries in predicate list, converting to choices
2162 -- and inserting in the list before the current choice. Note that
2163 -- if the list is empty, corresponding to a False predicate, then
2164 -- no choices are inserted.
2166 P
:= First
(Static_Discrete_Predicate
(Entity
(Choice
)));
2167 while Present
(P
) loop
2169 -- If low bound and high bounds are equal, copy simple choice
2171 if Expr_Value
(Low_Bound
(P
)) = Expr_Value
(High_Bound
(P
)) then
2172 C
:= New_Copy
(Low_Bound
(P
));
2174 -- Otherwise copy a range
2180 -- Change Sloc to referencing choice (rather than the Sloc of
2181 -- the predicate declaration element itself).
2183 Set_Sloc
(C
, Sloc
(Choice
));
2184 Insert_Before
(Choice
, C
);
2188 -- Delete the predicated entry
2193 -- Move to next choice to check
2197 end Expand_Static_Predicates_In_Choices
;
2199 ------------------------------
2200 -- Expand_Subtype_From_Expr --
2201 ------------------------------
2203 -- This function is applicable for both static and dynamic allocation of
2204 -- objects which are constrained by an initial expression. Basically it
2205 -- transforms an unconstrained subtype indication into a constrained one.
2207 -- The expression may also be transformed in certain cases in order to
2208 -- avoid multiple evaluation. In the static allocation case, the general
2213 -- is transformed into
2215 -- Val : Constrained_Subtype_of_T := Maybe_Modified_Expr;
2217 -- Here are the main cases :
2219 -- <if Expr is a Slice>
2220 -- Val : T ([Index_Subtype (Expr)]) := Expr;
2222 -- <elsif Expr is a String Literal>
2223 -- Val : T (T'First .. T'First + Length (string literal) - 1) := Expr;
2225 -- <elsif Expr is Constrained>
2226 -- subtype T is Type_Of_Expr
2229 -- <elsif Expr is an entity_name>
2230 -- Val : T (constraints taken from Expr) := Expr;
2233 -- type Axxx is access all T;
2234 -- Rval : Axxx := Expr'ref;
2235 -- Val : T (constraints taken from Rval) := Rval.all;
2237 -- ??? note: when the Expression is allocated in the secondary stack
2238 -- we could use it directly instead of copying it by declaring
2239 -- Val : T (...) renames Rval.all
2241 procedure Expand_Subtype_From_Expr
2243 Unc_Type
: Entity_Id
;
2244 Subtype_Indic
: Node_Id
;
2246 Related_Id
: Entity_Id
:= Empty
)
2248 Loc
: constant Source_Ptr
:= Sloc
(N
);
2249 Exp_Typ
: constant Entity_Id
:= Etype
(Exp
);
2253 -- In general we cannot build the subtype if expansion is disabled,
2254 -- because internal entities may not have been defined. However, to
2255 -- avoid some cascaded errors, we try to continue when the expression is
2256 -- an array (or string), because it is safe to compute the bounds. It is
2257 -- in fact required to do so even in a generic context, because there
2258 -- may be constants that depend on the bounds of a string literal, both
2259 -- standard string types and more generally arrays of characters.
2261 -- In GNATprove mode, these extra subtypes are not needed
2263 if GNATprove_Mode
then
2267 if not Expander_Active
2268 and then (No
(Etype
(Exp
)) or else not Is_String_Type
(Etype
(Exp
)))
2273 if Nkind
(Exp
) = N_Slice
then
2275 Slice_Type
: constant Entity_Id
:= Etype
(First_Index
(Exp_Typ
));
2278 Rewrite
(Subtype_Indic
,
2279 Make_Subtype_Indication
(Loc
,
2280 Subtype_Mark
=> New_Occurrence_Of
(Unc_Type
, Loc
),
2282 Make_Index_Or_Discriminant_Constraint
(Loc
,
2283 Constraints
=> New_List
2284 (New_Occurrence_Of
(Slice_Type
, Loc
)))));
2286 -- This subtype indication may be used later for constraint checks
2287 -- we better make sure that if a variable was used as a bound of
2288 -- of the original slice, its value is frozen.
2290 Evaluate_Slice_Bounds
(Exp
);
2293 elsif Ekind
(Exp_Typ
) = E_String_Literal_Subtype
then
2294 Rewrite
(Subtype_Indic
,
2295 Make_Subtype_Indication
(Loc
,
2296 Subtype_Mark
=> New_Occurrence_Of
(Unc_Type
, Loc
),
2298 Make_Index_Or_Discriminant_Constraint
(Loc
,
2299 Constraints
=> New_List
(
2300 Make_Literal_Range
(Loc
,
2301 Literal_Typ
=> Exp_Typ
)))));
2303 -- If the type of the expression is an internally generated type it
2304 -- may not be necessary to create a new subtype. However there are two
2305 -- exceptions: references to the current instances, and aliased array
2306 -- object declarations for which the backend needs to create a template.
2308 elsif Is_Constrained
(Exp_Typ
)
2309 and then not Is_Class_Wide_Type
(Unc_Type
)
2311 (Nkind
(N
) /= N_Object_Declaration
2312 or else not Is_Entity_Name
(Expression
(N
))
2313 or else not Comes_From_Source
(Entity
(Expression
(N
)))
2314 or else not Is_Array_Type
(Exp_Typ
)
2315 or else not Aliased_Present
(N
))
2317 if Is_Itype
(Exp_Typ
) then
2319 -- Within an initialization procedure, a selected component
2320 -- denotes a component of the enclosing record, and it appears as
2321 -- an actual in a call to its own initialization procedure. If
2322 -- this component depends on the outer discriminant, we must
2323 -- generate the proper actual subtype for it.
2325 if Nkind
(Exp
) = N_Selected_Component
2326 and then Within_Init_Proc
2329 Decl
: constant Node_Id
:=
2330 Build_Actual_Subtype_Of_Component
(Exp_Typ
, Exp
);
2332 if Present
(Decl
) then
2333 Insert_Action
(N
, Decl
);
2334 T
:= Defining_Identifier
(Decl
);
2340 -- No need to generate a new subtype
2347 T
:= Make_Temporary
(Loc
, 'T');
2350 Make_Subtype_Declaration
(Loc
,
2351 Defining_Identifier
=> T
,
2352 Subtype_Indication
=> New_Occurrence_Of
(Exp_Typ
, Loc
)));
2354 -- This type is marked as an itype even though it has an explicit
2355 -- declaration since otherwise Is_Generic_Actual_Type can get
2356 -- set, resulting in the generation of spurious errors. (See
2357 -- sem_ch8.Analyze_Package_Renaming and sem_type.covers)
2360 Set_Associated_Node_For_Itype
(T
, Exp
);
2363 Rewrite
(Subtype_Indic
, New_Occurrence_Of
(T
, Loc
));
2365 -- Nothing needs to be done for private types with unknown discriminants
2366 -- if the underlying type is not an unconstrained composite type or it
2367 -- is an unchecked union.
2369 elsif Is_Private_Type
(Unc_Type
)
2370 and then Has_Unknown_Discriminants
(Unc_Type
)
2371 and then (not Is_Composite_Type
(Underlying_Type
(Unc_Type
))
2372 or else Is_Constrained
(Underlying_Type
(Unc_Type
))
2373 or else Is_Unchecked_Union
(Underlying_Type
(Unc_Type
)))
2377 -- Case of derived type with unknown discriminants where the parent type
2378 -- also has unknown discriminants.
2380 elsif Is_Record_Type
(Unc_Type
)
2381 and then not Is_Class_Wide_Type
(Unc_Type
)
2382 and then Has_Unknown_Discriminants
(Unc_Type
)
2383 and then Has_Unknown_Discriminants
(Underlying_Type
(Unc_Type
))
2385 -- Nothing to be done if no underlying record view available
2387 if No
(Underlying_Record_View
(Unc_Type
)) then
2390 -- Otherwise use the Underlying_Record_View to create the proper
2391 -- constrained subtype for an object of a derived type with unknown
2395 Remove_Side_Effects
(Exp
);
2396 Rewrite
(Subtype_Indic
,
2397 Make_Subtype_From_Expr
(Exp
, Underlying_Record_View
(Unc_Type
)));
2400 -- Renamings of class-wide interface types require no equivalent
2401 -- constrained type declarations because we only need to reference
2402 -- the tag component associated with the interface. The same is
2403 -- presumably true for class-wide types in general, so this test
2404 -- is broadened to include all class-wide renamings, which also
2405 -- avoids cases of unbounded recursion in Remove_Side_Effects.
2406 -- (Is this really correct, or are there some cases of class-wide
2407 -- renamings that require action in this procedure???)
2410 and then Nkind
(N
) = N_Object_Renaming_Declaration
2411 and then Is_Class_Wide_Type
(Unc_Type
)
2415 -- In Ada 95 nothing to be done if the type of the expression is limited
2416 -- because in this case the expression cannot be copied, and its use can
2417 -- only be by reference.
2419 -- In Ada 2005 the context can be an object declaration whose expression
2420 -- is a function that returns in place. If the nominal subtype has
2421 -- unknown discriminants, the call still provides constraints on the
2422 -- object, and we have to create an actual subtype from it.
2424 -- If the type is class-wide, the expression is dynamically tagged and
2425 -- we do not create an actual subtype either. Ditto for an interface.
2426 -- For now this applies only if the type is immutably limited, and the
2427 -- function being called is build-in-place. This will have to be revised
2428 -- when build-in-place functions are generalized to other types.
2430 elsif Is_Limited_View
(Exp_Typ
)
2432 (Is_Class_Wide_Type
(Exp_Typ
)
2433 or else Is_Interface
(Exp_Typ
)
2434 or else not Has_Unknown_Discriminants
(Exp_Typ
)
2435 or else not Is_Composite_Type
(Unc_Type
))
2439 -- For limited objects initialized with build in place function calls,
2440 -- nothing to be done; otherwise we prematurely introduce an N_Reference
2441 -- node in the expression initializing the object, which breaks the
2442 -- circuitry that detects and adds the additional arguments to the
2445 elsif Is_Build_In_Place_Function_Call
(Exp
) then
2449 Remove_Side_Effects
(Exp
);
2450 Rewrite
(Subtype_Indic
,
2451 Make_Subtype_From_Expr
(Exp
, Unc_Type
, Related_Id
));
2453 end Expand_Subtype_From_Expr
;
2455 ----------------------
2456 -- Finalize_Address --
2457 ----------------------
2459 function Finalize_Address
(Typ
: Entity_Id
) return Entity_Id
is
2460 Utyp
: Entity_Id
:= Typ
;
2463 -- Handle protected class-wide or task class-wide types
2465 if Is_Class_Wide_Type
(Utyp
) then
2466 if Is_Concurrent_Type
(Root_Type
(Utyp
)) then
2467 Utyp
:= Root_Type
(Utyp
);
2469 elsif Is_Private_Type
(Root_Type
(Utyp
))
2470 and then Present
(Full_View
(Root_Type
(Utyp
)))
2471 and then Is_Concurrent_Type
(Full_View
(Root_Type
(Utyp
)))
2473 Utyp
:= Full_View
(Root_Type
(Utyp
));
2477 -- Handle private types
2479 if Is_Private_Type
(Utyp
) and then Present
(Full_View
(Utyp
)) then
2480 Utyp
:= Full_View
(Utyp
);
2483 -- Handle protected and task types
2485 if Is_Concurrent_Type
(Utyp
)
2486 and then Present
(Corresponding_Record_Type
(Utyp
))
2488 Utyp
:= Corresponding_Record_Type
(Utyp
);
2491 Utyp
:= Underlying_Type
(Base_Type
(Utyp
));
2493 -- Deal with untagged derivation of private views. If the parent is
2494 -- now known to be protected, the finalization routine is the one
2495 -- defined on the corresponding record of the ancestor (corresponding
2496 -- records do not automatically inherit operations, but maybe they
2499 if Is_Untagged_Derivation
(Typ
) then
2500 if Is_Protected_Type
(Typ
) then
2501 Utyp
:= Corresponding_Record_Type
(Root_Type
(Base_Type
(Typ
)));
2504 Utyp
:= Underlying_Type
(Root_Type
(Base_Type
(Typ
)));
2506 if Is_Protected_Type
(Utyp
) then
2507 Utyp
:= Corresponding_Record_Type
(Utyp
);
2512 -- If the underlying_type is a subtype, we are dealing with the
2513 -- completion of a private type. We need to access the base type and
2514 -- generate a conversion to it.
2516 if Utyp
/= Base_Type
(Utyp
) then
2517 pragma Assert
(Is_Private_Type
(Typ
));
2519 Utyp
:= Base_Type
(Utyp
);
2522 -- When dealing with an internally built full view for a type with
2523 -- unknown discriminants, use the original record type.
2525 if Is_Underlying_Record_View
(Utyp
) then
2526 Utyp
:= Etype
(Utyp
);
2529 return TSS
(Utyp
, TSS_Finalize_Address
);
2530 end Finalize_Address
;
2532 ------------------------
2533 -- Find_Interface_ADT --
2534 ------------------------
2536 function Find_Interface_ADT
2538 Iface
: Entity_Id
) return Elmt_Id
2541 Typ
: Entity_Id
:= T
;
2544 pragma Assert
(Is_Interface
(Iface
));
2546 -- Handle private types
2548 if Has_Private_Declaration
(Typ
) and then Present
(Full_View
(Typ
)) then
2549 Typ
:= Full_View
(Typ
);
2552 -- Handle access types
2554 if Is_Access_Type
(Typ
) then
2555 Typ
:= Designated_Type
(Typ
);
2558 -- Handle task and protected types implementing interfaces
2560 if Is_Concurrent_Type
(Typ
) then
2561 Typ
:= Corresponding_Record_Type
(Typ
);
2565 (not Is_Class_Wide_Type
(Typ
)
2566 and then Ekind
(Typ
) /= E_Incomplete_Type
);
2568 if Is_Ancestor
(Iface
, Typ
, Use_Full_View
=> True) then
2569 return First_Elmt
(Access_Disp_Table
(Typ
));
2572 ADT
:= Next_Elmt
(Next_Elmt
(First_Elmt
(Access_Disp_Table
(Typ
))));
2574 and then Present
(Related_Type
(Node
(ADT
)))
2575 and then Related_Type
(Node
(ADT
)) /= Iface
2576 and then not Is_Ancestor
(Iface
, Related_Type
(Node
(ADT
)),
2577 Use_Full_View
=> True)
2582 pragma Assert
(Present
(Related_Type
(Node
(ADT
))));
2585 end Find_Interface_ADT
;
2587 ------------------------
2588 -- Find_Interface_Tag --
2589 ------------------------
2591 function Find_Interface_Tag
2593 Iface
: Entity_Id
) return Entity_Id
2596 Found
: Boolean := False;
2597 Typ
: Entity_Id
:= T
;
2599 procedure Find_Tag
(Typ
: Entity_Id
);
2600 -- Internal subprogram used to recursively climb to the ancestors
2606 procedure Find_Tag
(Typ
: Entity_Id
) is
2611 -- This routine does not handle the case in which the interface is an
2612 -- ancestor of Typ. That case is handled by the enclosing subprogram.
2614 pragma Assert
(Typ
/= Iface
);
2616 -- Climb to the root type handling private types
2618 if Present
(Full_View
(Etype
(Typ
))) then
2619 if Full_View
(Etype
(Typ
)) /= Typ
then
2620 Find_Tag
(Full_View
(Etype
(Typ
)));
2623 elsif Etype
(Typ
) /= Typ
then
2624 Find_Tag
(Etype
(Typ
));
2627 -- Traverse the list of interfaces implemented by the type
2630 and then Present
(Interfaces
(Typ
))
2631 and then not (Is_Empty_Elmt_List
(Interfaces
(Typ
)))
2633 -- Skip the tag associated with the primary table
2635 pragma Assert
(Etype
(First_Tag_Component
(Typ
)) = RTE
(RE_Tag
));
2636 AI_Tag
:= Next_Tag_Component
(First_Tag_Component
(Typ
));
2637 pragma Assert
(Present
(AI_Tag
));
2639 AI_Elmt
:= First_Elmt
(Interfaces
(Typ
));
2640 while Present
(AI_Elmt
) loop
2641 AI
:= Node
(AI_Elmt
);
2644 or else Is_Ancestor
(Iface
, AI
, Use_Full_View
=> True)
2650 AI_Tag
:= Next_Tag_Component
(AI_Tag
);
2651 Next_Elmt
(AI_Elmt
);
2656 -- Start of processing for Find_Interface_Tag
2659 pragma Assert
(Is_Interface
(Iface
));
2661 -- Handle access types
2663 if Is_Access_Type
(Typ
) then
2664 Typ
:= Designated_Type
(Typ
);
2667 -- Handle class-wide types
2669 if Is_Class_Wide_Type
(Typ
) then
2670 Typ
:= Root_Type
(Typ
);
2673 -- Handle private types
2675 if Has_Private_Declaration
(Typ
) and then Present
(Full_View
(Typ
)) then
2676 Typ
:= Full_View
(Typ
);
2679 -- Handle entities from the limited view
2681 if Ekind
(Typ
) = E_Incomplete_Type
then
2682 pragma Assert
(Present
(Non_Limited_View
(Typ
)));
2683 Typ
:= Non_Limited_View
(Typ
);
2686 -- Handle task and protected types implementing interfaces
2688 if Is_Concurrent_Type
(Typ
) then
2689 Typ
:= Corresponding_Record_Type
(Typ
);
2692 -- If the interface is an ancestor of the type, then it shared the
2693 -- primary dispatch table.
2695 if Is_Ancestor
(Iface
, Typ
, Use_Full_View
=> True) then
2696 pragma Assert
(Etype
(First_Tag_Component
(Typ
)) = RTE
(RE_Tag
));
2697 return First_Tag_Component
(Typ
);
2699 -- Otherwise we need to search for its associated tag component
2703 pragma Assert
(Found
);
2706 end Find_Interface_Tag
;
2708 ---------------------------
2709 -- Find_Optional_Prim_Op --
2710 ---------------------------
2712 function Find_Optional_Prim_Op
2713 (T
: Entity_Id
; Name
: Name_Id
) return Entity_Id
2716 Typ
: Entity_Id
:= T
;
2720 if Is_Class_Wide_Type
(Typ
) then
2721 Typ
:= Root_Type
(Typ
);
2724 Typ
:= Underlying_Type
(Typ
);
2726 -- Loop through primitive operations
2728 Prim
:= First_Elmt
(Primitive_Operations
(Typ
));
2729 while Present
(Prim
) loop
2732 -- We can retrieve primitive operations by name if it is an internal
2733 -- name. For equality we must check that both of its operands have
2734 -- the same type, to avoid confusion with user-defined equalities
2735 -- than may have a non-symmetric signature.
2737 exit when Chars
(Op
) = Name
2740 or else Etype
(First_Formal
(Op
)) = Etype
(Last_Formal
(Op
)));
2745 return Node
(Prim
); -- Empty if not found
2746 end Find_Optional_Prim_Op
;
2748 ---------------------------
2749 -- Find_Optional_Prim_Op --
2750 ---------------------------
2752 function Find_Optional_Prim_Op
2754 Name
: TSS_Name_Type
) return Entity_Id
2756 Inher_Op
: Entity_Id
:= Empty
;
2757 Own_Op
: Entity_Id
:= Empty
;
2758 Prim_Elmt
: Elmt_Id
;
2759 Prim_Id
: Entity_Id
;
2760 Typ
: Entity_Id
:= T
;
2763 if Is_Class_Wide_Type
(Typ
) then
2764 Typ
:= Root_Type
(Typ
);
2767 Typ
:= Underlying_Type
(Typ
);
2769 -- This search is based on the assertion that the dispatching version
2770 -- of the TSS routine always precedes the real primitive.
2772 Prim_Elmt
:= First_Elmt
(Primitive_Operations
(Typ
));
2773 while Present
(Prim_Elmt
) loop
2774 Prim_Id
:= Node
(Prim_Elmt
);
2776 if Is_TSS
(Prim_Id
, Name
) then
2777 if Present
(Alias
(Prim_Id
)) then
2778 Inher_Op
:= Prim_Id
;
2784 Next_Elmt
(Prim_Elmt
);
2787 if Present
(Own_Op
) then
2789 elsif Present
(Inher_Op
) then
2794 end Find_Optional_Prim_Op
;
2800 function Find_Prim_Op
2801 (T
: Entity_Id
; Name
: Name_Id
) return Entity_Id
2803 Result
: constant Entity_Id
:= Find_Optional_Prim_Op
(T
, Name
);
2806 raise Program_Error
;
2816 function Find_Prim_Op
2818 Name
: TSS_Name_Type
) return Entity_Id
2820 Result
: constant Entity_Id
:= Find_Optional_Prim_Op
(T
, Name
);
2823 raise Program_Error
;
2829 ----------------------------
2830 -- Find_Protection_Object --
2831 ----------------------------
2833 function Find_Protection_Object
(Scop
: Entity_Id
) return Entity_Id
is
2838 while Present
(S
) loop
2839 if Ekind_In
(S
, E_Entry
, E_Entry_Family
, E_Function
, E_Procedure
)
2840 and then Present
(Protection_Object
(S
))
2842 return Protection_Object
(S
);
2848 -- If we do not find a Protection object in the scope chain, then
2849 -- something has gone wrong, most likely the object was never created.
2851 raise Program_Error
;
2852 end Find_Protection_Object
;
2854 --------------------------
2855 -- Find_Protection_Type --
2856 --------------------------
2858 function Find_Protection_Type
(Conc_Typ
: Entity_Id
) return Entity_Id
is
2860 Typ
: Entity_Id
:= Conc_Typ
;
2863 if Is_Concurrent_Type
(Typ
) then
2864 Typ
:= Corresponding_Record_Type
(Typ
);
2867 -- Since restriction violations are not considered serious errors, the
2868 -- expander remains active, but may leave the corresponding record type
2869 -- malformed. In such cases, component _object is not available so do
2872 if not Analyzed
(Typ
) then
2876 Comp
:= First_Component
(Typ
);
2877 while Present
(Comp
) loop
2878 if Chars
(Comp
) = Name_uObject
then
2879 return Base_Type
(Etype
(Comp
));
2882 Next_Component
(Comp
);
2885 -- The corresponding record of a protected type should always have an
2888 raise Program_Error
;
2889 end Find_Protection_Type
;
2891 -----------------------
2892 -- Find_Hook_Context --
2893 -----------------------
2895 function Find_Hook_Context
(N
: Node_Id
) return Node_Id
is
2899 Wrapped_Node
: Node_Id
;
2900 -- Note: if we are in a transient scope, we want to reuse it as
2901 -- the context for actions insertion, if possible. But if N is itself
2902 -- part of the stored actions for the current transient scope,
2903 -- then we need to insert at the appropriate (inner) location in
2904 -- the not as an action on Node_To_Be_Wrapped.
2906 In_Cond_Expr
: constant Boolean := Within_Case_Or_If_Expression
(N
);
2909 -- When the node is inside a case/if expression, the lifetime of any
2910 -- temporary controlled object is extended. Find a suitable insertion
2911 -- node by locating the topmost case or if expressions.
2913 if In_Cond_Expr
then
2916 while Present
(Par
) loop
2917 if Nkind_In
(Original_Node
(Par
), N_Case_Expression
,
2922 -- Prevent the search from going too far
2924 elsif Is_Body_Or_Package_Declaration
(Par
) then
2928 Par
:= Parent
(Par
);
2931 -- The topmost case or if expression is now recovered, but it may
2932 -- still not be the correct place to add generated code. Climb to
2933 -- find a parent that is part of a declarative or statement list,
2934 -- and is not a list of actuals in a call.
2937 while Present
(Par
) loop
2938 if Is_List_Member
(Par
)
2939 and then not Nkind_In
(Par
, N_Component_Association
,
2940 N_Discriminant_Association
,
2941 N_Parameter_Association
,
2942 N_Pragma_Argument_Association
)
2943 and then not Nkind_In
2944 (Parent
(Par
), N_Function_Call
,
2945 N_Procedure_Call_Statement
,
2946 N_Entry_Call_Statement
)
2951 -- Prevent the search from going too far
2953 elsif Is_Body_Or_Package_Declaration
(Par
) then
2957 Par
:= Parent
(Par
);
2964 while Present
(Par
) loop
2966 -- Keep climbing past various operators
2968 if Nkind
(Parent
(Par
)) in N_Op
2969 or else Nkind_In
(Parent
(Par
), N_And_Then
, N_Or_Else
)
2971 Par
:= Parent
(Par
);
2979 -- The node may be located in a pragma in which case return the
2982 -- pragma Precondition (... and then Ctrl_Func_Call ...);
2984 -- Similar case occurs when the node is related to an object
2985 -- declaration or assignment:
2987 -- Obj [: Some_Typ] := ... and then Ctrl_Func_Call ...;
2989 -- Another case to consider is when the node is part of a return
2992 -- return ... and then Ctrl_Func_Call ...;
2994 -- Another case is when the node acts as a formal in a procedure
2997 -- Proc (... and then Ctrl_Func_Call ...);
2999 if Scope_Is_Transient
then
3000 Wrapped_Node
:= Node_To_Be_Wrapped
;
3002 Wrapped_Node
:= Empty
;
3005 while Present
(Par
) loop
3006 if Par
= Wrapped_Node
3007 or else Nkind_In
(Par
, N_Assignment_Statement
,
3008 N_Object_Declaration
,
3010 N_Procedure_Call_Statement
,
3011 N_Simple_Return_Statement
)
3015 -- Prevent the search from going too far
3017 elsif Is_Body_Or_Package_Declaration
(Par
) then
3021 Par
:= Parent
(Par
);
3024 -- Return the topmost short circuit operator
3028 end Find_Hook_Context
;
3030 ------------------------------
3031 -- Following_Address_Clause --
3032 ------------------------------
3034 function Following_Address_Clause
(D
: Node_Id
) return Node_Id
is
3035 Id
: constant Entity_Id
:= Defining_Identifier
(D
);
3039 function Check_Decls
(D
: Node_Id
) return Node_Id
;
3040 -- This internal function differs from the main function in that it
3041 -- gets called to deal with a following package private part, and
3042 -- it checks declarations starting with D (the main function checks
3043 -- declarations following D). If D is Empty, then Empty is returned.
3049 function Check_Decls
(D
: Node_Id
) return Node_Id
is
3054 while Present
(Decl
) loop
3055 if Nkind
(Decl
) = N_At_Clause
3056 and then Chars
(Identifier
(Decl
)) = Chars
(Id
)
3060 elsif Nkind
(Decl
) = N_Attribute_Definition_Clause
3061 and then Chars
(Decl
) = Name_Address
3062 and then Chars
(Name
(Decl
)) = Chars
(Id
)
3070 -- Otherwise not found, return Empty
3075 -- Start of processing for Following_Address_Clause
3078 -- If parser detected no address clause for the identifier in question,
3079 -- then the answer is a quick NO, without the need for a search.
3081 if not Get_Name_Table_Boolean1
(Chars
(Id
)) then
3085 -- Otherwise search current declarative unit
3087 Result
:= Check_Decls
(Next
(D
));
3089 if Present
(Result
) then
3093 -- Check for possible package private part following
3097 if Nkind
(Par
) = N_Package_Specification
3098 and then Visible_Declarations
(Par
) = List_Containing
(D
)
3099 and then Present
(Private_Declarations
(Par
))
3101 -- Private part present, check declarations there
3103 return Check_Decls
(First
(Private_Declarations
(Par
)));
3106 -- No private part, clause not found, return Empty
3110 end Following_Address_Clause
;
3112 ----------------------
3113 -- Force_Evaluation --
3114 ----------------------
3116 procedure Force_Evaluation
3118 Name_Req
: Boolean := False;
3119 Related_Id
: Entity_Id
:= Empty
;
3120 Is_Low_Bound
: Boolean := False;
3121 Is_High_Bound
: Boolean := False)
3126 Name_Req
=> Name_Req
,
3127 Variable_Ref
=> True,
3128 Renaming_Req
=> False,
3129 Related_Id
=> Related_Id
,
3130 Is_Low_Bound
=> Is_Low_Bound
,
3131 Is_High_Bound
=> Is_High_Bound
);
3132 end Force_Evaluation
;
3134 ---------------------------------
3135 -- Fully_Qualified_Name_String --
3136 ---------------------------------
3138 function Fully_Qualified_Name_String
3140 Append_NUL
: Boolean := True) return String_Id
3142 procedure Internal_Full_Qualified_Name
(E
: Entity_Id
);
3143 -- Compute recursively the qualified name without NUL at the end, adding
3144 -- it to the currently started string being generated
3146 ----------------------------------
3147 -- Internal_Full_Qualified_Name --
3148 ----------------------------------
3150 procedure Internal_Full_Qualified_Name
(E
: Entity_Id
) is
3154 -- Deal properly with child units
3156 if Nkind
(E
) = N_Defining_Program_Unit_Name
then
3157 Ent
:= Defining_Identifier
(E
);
3162 -- Compute qualification recursively (only "Standard" has no scope)
3164 if Present
(Scope
(Scope
(Ent
))) then
3165 Internal_Full_Qualified_Name
(Scope
(Ent
));
3166 Store_String_Char
(Get_Char_Code
('.'));
3169 -- Every entity should have a name except some expanded blocks
3170 -- don't bother about those.
3172 if Chars
(Ent
) = No_Name
then
3176 -- Generates the entity name in upper case
3178 Get_Decoded_Name_String
(Chars
(Ent
));
3180 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
3182 end Internal_Full_Qualified_Name
;
3184 -- Start of processing for Full_Qualified_Name
3188 Internal_Full_Qualified_Name
(E
);
3191 Store_String_Char
(Get_Char_Code
(ASCII
.NUL
));
3195 end Fully_Qualified_Name_String
;
3197 ------------------------
3198 -- Generate_Poll_Call --
3199 ------------------------
3201 procedure Generate_Poll_Call
(N
: Node_Id
) is
3203 -- No poll call if polling not active
3205 if not Polling_Required
then
3208 -- Otherwise generate require poll call
3211 Insert_Before_And_Analyze
(N
,
3212 Make_Procedure_Call_Statement
(Sloc
(N
),
3213 Name
=> New_Occurrence_Of
(RTE
(RE_Poll
), Sloc
(N
))));
3215 end Generate_Poll_Call
;
3217 ---------------------------------
3218 -- Get_Current_Value_Condition --
3219 ---------------------------------
3221 -- Note: the implementation of this procedure is very closely tied to the
3222 -- implementation of Set_Current_Value_Condition. In the Get procedure, we
3223 -- interpret Current_Value fields set by the Set procedure, so the two
3224 -- procedures need to be closely coordinated.
3226 procedure Get_Current_Value_Condition
3231 Loc
: constant Source_Ptr
:= Sloc
(Var
);
3232 Ent
: constant Entity_Id
:= Entity
(Var
);
3234 procedure Process_Current_Value_Condition
3237 -- N is an expression which holds either True (S = True) or False (S =
3238 -- False) in the condition. This procedure digs out the expression and
3239 -- if it refers to Ent, sets Op and Val appropriately.
3241 -------------------------------------
3242 -- Process_Current_Value_Condition --
3243 -------------------------------------
3245 procedure Process_Current_Value_Condition
3250 Prev_Cond
: Node_Id
;
3260 -- Deal with NOT operators, inverting sense
3262 while Nkind
(Cond
) = N_Op_Not
loop
3263 Cond
:= Right_Opnd
(Cond
);
3267 -- Deal with conversions, qualifications, and expressions with
3270 while Nkind_In
(Cond
,
3272 N_Qualified_Expression
,
3273 N_Expression_With_Actions
)
3275 Cond
:= Expression
(Cond
);
3278 exit when Cond
= Prev_Cond
;
3281 -- Deal with AND THEN and AND cases
3283 if Nkind_In
(Cond
, N_And_Then
, N_Op_And
) then
3285 -- Don't ever try to invert a condition that is of the form of an
3286 -- AND or AND THEN (since we are not doing sufficiently general
3287 -- processing to allow this).
3289 if Sens
= False then
3295 -- Recursively process AND and AND THEN branches
3297 Process_Current_Value_Condition
(Left_Opnd
(Cond
), True);
3299 if Op
/= N_Empty
then
3303 Process_Current_Value_Condition
(Right_Opnd
(Cond
), True);
3306 -- Case of relational operator
3308 elsif Nkind
(Cond
) in N_Op_Compare
then
3311 -- Invert sense of test if inverted test
3313 if Sens
= False then
3315 when N_Op_Eq
=> Op
:= N_Op_Ne
;
3316 when N_Op_Ne
=> Op
:= N_Op_Eq
;
3317 when N_Op_Lt
=> Op
:= N_Op_Ge
;
3318 when N_Op_Gt
=> Op
:= N_Op_Le
;
3319 when N_Op_Le
=> Op
:= N_Op_Gt
;
3320 when N_Op_Ge
=> Op
:= N_Op_Lt
;
3321 when others => raise Program_Error
;
3325 -- Case of entity op value
3327 if Is_Entity_Name
(Left_Opnd
(Cond
))
3328 and then Ent
= Entity
(Left_Opnd
(Cond
))
3329 and then Compile_Time_Known_Value
(Right_Opnd
(Cond
))
3331 Val
:= Right_Opnd
(Cond
);
3333 -- Case of value op entity
3335 elsif Is_Entity_Name
(Right_Opnd
(Cond
))
3336 and then Ent
= Entity
(Right_Opnd
(Cond
))
3337 and then Compile_Time_Known_Value
(Left_Opnd
(Cond
))
3339 Val
:= Left_Opnd
(Cond
);
3341 -- We are effectively swapping operands
3344 when N_Op_Eq
=> null;
3345 when N_Op_Ne
=> null;
3346 when N_Op_Lt
=> Op
:= N_Op_Gt
;
3347 when N_Op_Gt
=> Op
:= N_Op_Lt
;
3348 when N_Op_Le
=> Op
:= N_Op_Ge
;
3349 when N_Op_Ge
=> Op
:= N_Op_Le
;
3350 when others => raise Program_Error
;
3359 elsif Nkind_In
(Cond
,
3361 N_Qualified_Expression
,
3362 N_Expression_With_Actions
)
3364 Cond
:= Expression
(Cond
);
3366 -- Case of Boolean variable reference, return as though the
3367 -- reference had said var = True.
3370 if Is_Entity_Name
(Cond
) and then Ent
= Entity
(Cond
) then
3371 Val
:= New_Occurrence_Of
(Standard_True
, Sloc
(Cond
));
3373 if Sens
= False then
3380 end Process_Current_Value_Condition
;
3382 -- Start of processing for Get_Current_Value_Condition
3388 -- Immediate return, nothing doing, if this is not an object
3390 if Ekind
(Ent
) not in Object_Kind
then
3394 -- Otherwise examine current value
3397 CV
: constant Node_Id
:= Current_Value
(Ent
);
3402 -- If statement. Condition is known true in THEN section, known False
3403 -- in any ELSIF or ELSE part, and unknown outside the IF statement.
3405 if Nkind
(CV
) = N_If_Statement
then
3407 -- Before start of IF statement
3409 if Loc
< Sloc
(CV
) then
3412 -- After end of IF statement
3414 elsif Loc
>= Sloc
(CV
) + Text_Ptr
(UI_To_Int
(End_Span
(CV
))) then
3418 -- At this stage we know that we are within the IF statement, but
3419 -- unfortunately, the tree does not record the SLOC of the ELSE so
3420 -- we cannot use a simple SLOC comparison to distinguish between
3421 -- the then/else statements, so we have to climb the tree.
3428 while Parent
(N
) /= CV
loop
3431 -- If we fall off the top of the tree, then that's odd, but
3432 -- perhaps it could occur in some error situation, and the
3433 -- safest response is simply to assume that the outcome of
3434 -- the condition is unknown. No point in bombing during an
3435 -- attempt to optimize things.
3442 -- Now we have N pointing to a node whose parent is the IF
3443 -- statement in question, so now we can tell if we are within
3444 -- the THEN statements.
3446 if Is_List_Member
(N
)
3447 and then List_Containing
(N
) = Then_Statements
(CV
)
3451 -- If the variable reference does not come from source, we
3452 -- cannot reliably tell whether it appears in the else part.
3453 -- In particular, if it appears in generated code for a node
3454 -- that requires finalization, it may be attached to a list
3455 -- that has not been yet inserted into the code. For now,
3456 -- treat it as unknown.
3458 elsif not Comes_From_Source
(N
) then
3461 -- Otherwise we must be in ELSIF or ELSE part
3468 -- ELSIF part. Condition is known true within the referenced
3469 -- ELSIF, known False in any subsequent ELSIF or ELSE part,
3470 -- and unknown before the ELSE part or after the IF statement.
3472 elsif Nkind
(CV
) = N_Elsif_Part
then
3474 -- if the Elsif_Part had condition_actions, the elsif has been
3475 -- rewritten as a nested if, and the original elsif_part is
3476 -- detached from the tree, so there is no way to obtain useful
3477 -- information on the current value of the variable.
3478 -- Can this be improved ???
3480 if No
(Parent
(CV
)) then
3486 -- If the tree has been otherwise rewritten there is nothing
3487 -- else to be done either.
3489 if Nkind
(Stm
) /= N_If_Statement
then
3493 -- Before start of ELSIF part
3495 if Loc
< Sloc
(CV
) then
3498 -- After end of IF statement
3500 elsif Loc
>= Sloc
(Stm
) +
3501 Text_Ptr
(UI_To_Int
(End_Span
(Stm
)))
3506 -- Again we lack the SLOC of the ELSE, so we need to climb the
3507 -- tree to see if we are within the ELSIF part in question.
3514 while Parent
(N
) /= Stm
loop
3517 -- If we fall off the top of the tree, then that's odd, but
3518 -- perhaps it could occur in some error situation, and the
3519 -- safest response is simply to assume that the outcome of
3520 -- the condition is unknown. No point in bombing during an
3521 -- attempt to optimize things.
3528 -- Now we have N pointing to a node whose parent is the IF
3529 -- statement in question, so see if is the ELSIF part we want.
3530 -- the THEN statements.
3535 -- Otherwise we must be in subsequent ELSIF or ELSE part
3542 -- Iteration scheme of while loop. The condition is known to be
3543 -- true within the body of the loop.
3545 elsif Nkind
(CV
) = N_Iteration_Scheme
then
3547 Loop_Stmt
: constant Node_Id
:= Parent
(CV
);
3550 -- Before start of body of loop
3552 if Loc
< Sloc
(Loop_Stmt
) then
3555 -- After end of LOOP statement
3557 elsif Loc
>= Sloc
(End_Label
(Loop_Stmt
)) then
3560 -- We are within the body of the loop
3567 -- All other cases of Current_Value settings
3573 -- If we fall through here, then we have a reportable condition, Sens
3574 -- is True if the condition is true and False if it needs inverting.
3576 Process_Current_Value_Condition
(Condition
(CV
), Sens
);
3578 end Get_Current_Value_Condition
;
3580 ---------------------
3581 -- Get_Stream_Size --
3582 ---------------------
3584 function Get_Stream_Size
(E
: Entity_Id
) return Uint
is
3586 -- If we have a Stream_Size clause for this type use it
3588 if Has_Stream_Size_Clause
(E
) then
3589 return Static_Integer
(Expression
(Stream_Size_Clause
(E
)));
3591 -- Otherwise the Stream_Size if the size of the type
3596 end Get_Stream_Size
;
3598 ---------------------------
3599 -- Has_Access_Constraint --
3600 ---------------------------
3602 function Has_Access_Constraint
(E
: Entity_Id
) return Boolean is
3604 T
: constant Entity_Id
:= Etype
(E
);
3607 if Has_Per_Object_Constraint
(E
) and then Has_Discriminants
(T
) then
3608 Disc
:= First_Discriminant
(T
);
3609 while Present
(Disc
) loop
3610 if Is_Access_Type
(Etype
(Disc
)) then
3614 Next_Discriminant
(Disc
);
3621 end Has_Access_Constraint
;
3623 -----------------------------------------------------
3624 -- Has_Annotate_Pragma_For_External_Axiomatization --
3625 -----------------------------------------------------
3627 function Has_Annotate_Pragma_For_External_Axiomatization
3628 (E
: Entity_Id
) return Boolean
3630 function Is_Annotate_Pragma_For_External_Axiomatization
3631 (N
: Node_Id
) return Boolean;
3632 -- Returns whether N is
3633 -- pragma Annotate (GNATprove, External_Axiomatization);
3635 ----------------------------------------------------
3636 -- Is_Annotate_Pragma_For_External_Axiomatization --
3637 ----------------------------------------------------
3639 -- The general form of pragma Annotate is
3641 -- pragma Annotate (IDENTIFIER [, IDENTIFIER {, ARG}]);
3642 -- ARG ::= NAME | EXPRESSION
3644 -- The first two arguments are by convention intended to refer to an
3645 -- external tool and a tool-specific function. These arguments are
3648 -- The following is used to annotate a package specification which
3649 -- GNATprove should treat specially, because the axiomatization of
3650 -- this unit is given by the user instead of being automatically
3653 -- pragma Annotate (GNATprove, External_Axiomatization);
3655 function Is_Annotate_Pragma_For_External_Axiomatization
3656 (N
: Node_Id
) return Boolean
3658 Name_GNATprove
: constant String :=
3660 Name_External_Axiomatization
: constant String :=
3661 "external_axiomatization";
3665 if Nkind
(N
) = N_Pragma
3666 and then Get_Pragma_Id
(Pragma_Name
(N
)) = Pragma_Annotate
3667 and then List_Length
(Pragma_Argument_Associations
(N
)) = 2
3670 Arg1
: constant Node_Id
:=
3671 First
(Pragma_Argument_Associations
(N
));
3672 Arg2
: constant Node_Id
:= Next
(Arg1
);
3677 -- Fill in Name_Buffer with Name_GNATprove first, and then with
3678 -- Name_External_Axiomatization so that Name_Find returns the
3679 -- corresponding name. This takes care of all possible casings.
3682 Add_Str_To_Name_Buffer
(Name_GNATprove
);
3686 Add_Str_To_Name_Buffer
(Name_External_Axiomatization
);
3689 return Chars
(Get_Pragma_Arg
(Arg1
)) = Nam1
3691 Chars
(Get_Pragma_Arg
(Arg2
)) = Nam2
;
3697 end Is_Annotate_Pragma_For_External_Axiomatization
;
3702 Vis_Decls
: List_Id
;
3705 -- Start of processing for Has_Annotate_Pragma_For_External_Axiomatization
3708 if Nkind
(Parent
(E
)) = N_Defining_Program_Unit_Name
then
3709 Decl
:= Parent
(Parent
(E
));
3714 Vis_Decls
:= Visible_Declarations
(Decl
);
3716 N
:= First
(Vis_Decls
);
3717 while Present
(N
) loop
3719 -- Skip declarations generated by the frontend. Skip all pragmas
3720 -- that are not the desired Annotate pragma. Stop the search on
3721 -- the first non-pragma source declaration.
3723 if Comes_From_Source
(N
) then
3724 if Nkind
(N
) = N_Pragma
then
3725 if Is_Annotate_Pragma_For_External_Axiomatization
(N
) then
3737 end Has_Annotate_Pragma_For_External_Axiomatization
;
3739 --------------------
3740 -- Homonym_Number --
3741 --------------------
3743 function Homonym_Number
(Subp
: Entity_Id
) return Nat
is
3749 Hom
:= Homonym
(Subp
);
3750 while Present
(Hom
) loop
3751 if Scope
(Hom
) = Scope
(Subp
) then
3755 Hom
:= Homonym
(Hom
);
3761 -----------------------------------
3762 -- In_Library_Level_Package_Body --
3763 -----------------------------------
3765 function In_Library_Level_Package_Body
(Id
: Entity_Id
) return Boolean is
3767 -- First determine whether the entity appears at the library level, then
3768 -- look at the containing unit.
3770 if Is_Library_Level_Entity
(Id
) then
3772 Container
: constant Node_Id
:= Cunit
(Get_Source_Unit
(Id
));
3775 return Nkind
(Unit
(Container
)) = N_Package_Body
;
3780 end In_Library_Level_Package_Body
;
3782 ------------------------------
3783 -- In_Unconditional_Context --
3784 ------------------------------
3786 function In_Unconditional_Context
(Node
: Node_Id
) return Boolean is
3791 while Present
(P
) loop
3793 when N_Subprogram_Body
=>
3796 when N_If_Statement
=>
3799 when N_Loop_Statement
=>
3802 when N_Case_Statement
=>
3811 end In_Unconditional_Context
;
3817 procedure Insert_Action
(Assoc_Node
: Node_Id
; Ins_Action
: Node_Id
) is
3819 if Present
(Ins_Action
) then
3820 Insert_Actions
(Assoc_Node
, New_List
(Ins_Action
));
3824 -- Version with check(s) suppressed
3826 procedure Insert_Action
3827 (Assoc_Node
: Node_Id
; Ins_Action
: Node_Id
; Suppress
: Check_Id
)
3830 Insert_Actions
(Assoc_Node
, New_List
(Ins_Action
), Suppress
);
3833 -------------------------
3834 -- Insert_Action_After --
3835 -------------------------
3837 procedure Insert_Action_After
3838 (Assoc_Node
: Node_Id
;
3839 Ins_Action
: Node_Id
)
3842 Insert_Actions_After
(Assoc_Node
, New_List
(Ins_Action
));
3843 end Insert_Action_After
;
3845 --------------------
3846 -- Insert_Actions --
3847 --------------------
3849 procedure Insert_Actions
(Assoc_Node
: Node_Id
; Ins_Actions
: List_Id
) is
3853 Wrapped_Node
: Node_Id
:= Empty
;
3856 if No
(Ins_Actions
) or else Is_Empty_List
(Ins_Actions
) then
3860 -- Ignore insert of actions from inside default expression (or other
3861 -- similar "spec expression") in the special spec-expression analyze
3862 -- mode. Any insertions at this point have no relevance, since we are
3863 -- only doing the analyze to freeze the types of any static expressions.
3864 -- See section "Handling of Default Expressions" in the spec of package
3865 -- Sem for further details.
3867 if In_Spec_Expression
then
3871 -- If the action derives from stuff inside a record, then the actions
3872 -- are attached to the current scope, to be inserted and analyzed on
3873 -- exit from the scope. The reason for this is that we may also be
3874 -- generating freeze actions at the same time, and they must eventually
3875 -- be elaborated in the correct order.
3877 if Is_Record_Type
(Current_Scope
)
3878 and then not Is_Frozen
(Current_Scope
)
3880 if No
(Scope_Stack
.Table
3881 (Scope_Stack
.Last
).Pending_Freeze_Actions
)
3883 Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
:=
3888 Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
);
3894 -- We now intend to climb up the tree to find the right point to
3895 -- insert the actions. We start at Assoc_Node, unless this node is a
3896 -- subexpression in which case we start with its parent. We do this for
3897 -- two reasons. First it speeds things up. Second, if Assoc_Node is
3898 -- itself one of the special nodes like N_And_Then, then we assume that
3899 -- an initial request to insert actions for such a node does not expect
3900 -- the actions to get deposited in the node for later handling when the
3901 -- node is expanded, since clearly the node is being dealt with by the
3902 -- caller. Note that in the subexpression case, N is always the child we
3905 -- N_Raise_xxx_Error is an annoying special case, it is a statement
3906 -- if it has type Standard_Void_Type, and a subexpression otherwise.
3907 -- Procedure calls, and similarly procedure attribute references, are
3910 if Nkind
(Assoc_Node
) in N_Subexpr
3911 and then (Nkind
(Assoc_Node
) not in N_Raise_xxx_Error
3912 or else Etype
(Assoc_Node
) /= Standard_Void_Type
)
3913 and then Nkind
(Assoc_Node
) /= N_Procedure_Call_Statement
3914 and then (Nkind
(Assoc_Node
) /= N_Attribute_Reference
3915 or else not Is_Procedure_Attribute_Name
3916 (Attribute_Name
(Assoc_Node
)))
3919 P
:= Parent
(Assoc_Node
);
3921 -- Non-subexpression case. Note that N is initially Empty in this case
3922 -- (N is only guaranteed Non-Empty in the subexpr case).
3929 -- Capture root of the transient scope
3931 if Scope_Is_Transient
then
3932 Wrapped_Node
:= Node_To_Be_Wrapped
;
3936 pragma Assert
(Present
(P
));
3938 -- Make sure that inserted actions stay in the transient scope
3940 if Present
(Wrapped_Node
) and then N
= Wrapped_Node
then
3941 Store_Before_Actions_In_Scope
(Ins_Actions
);
3947 -- Case of right operand of AND THEN or OR ELSE. Put the actions
3948 -- in the Actions field of the right operand. They will be moved
3949 -- out further when the AND THEN or OR ELSE operator is expanded.
3950 -- Nothing special needs to be done for the left operand since
3951 -- in that case the actions are executed unconditionally.
3953 when N_Short_Circuit
=>
3954 if N
= Right_Opnd
(P
) then
3956 -- We are now going to either append the actions to the
3957 -- actions field of the short-circuit operation. We will
3958 -- also analyze the actions now.
3960 -- This analysis is really too early, the proper thing would
3961 -- be to just park them there now, and only analyze them if
3962 -- we find we really need them, and to it at the proper
3963 -- final insertion point. However attempting to this proved
3964 -- tricky, so for now we just kill current values before and
3965 -- after the analyze call to make sure we avoid peculiar
3966 -- optimizations from this out of order insertion.
3968 Kill_Current_Values
;
3970 -- If P has already been expanded, we can't park new actions
3971 -- on it, so we need to expand them immediately, introducing
3972 -- an Expression_With_Actions. N can't be an expression
3973 -- with actions, or else then the actions would have been
3974 -- inserted at an inner level.
3976 if Analyzed
(P
) then
3977 pragma Assert
(Nkind
(N
) /= N_Expression_With_Actions
);
3979 Make_Expression_With_Actions
(Sloc
(N
),
3980 Actions
=> Ins_Actions
,
3981 Expression
=> Relocate_Node
(N
)));
3982 Analyze_And_Resolve
(N
);
3984 elsif Present
(Actions
(P
)) then
3985 Insert_List_After_And_Analyze
3986 (Last
(Actions
(P
)), Ins_Actions
);
3988 Set_Actions
(P
, Ins_Actions
);
3989 Analyze_List
(Actions
(P
));
3992 Kill_Current_Values
;
3997 -- Then or Else dependent expression of an if expression. Add
3998 -- actions to Then_Actions or Else_Actions field as appropriate.
3999 -- The actions will be moved further out when the if is expanded.
4001 when N_If_Expression
=>
4003 ThenX
: constant Node_Id
:= Next
(First
(Expressions
(P
)));
4004 ElseX
: constant Node_Id
:= Next
(ThenX
);
4007 -- If the enclosing expression is already analyzed, as
4008 -- is the case for nested elaboration checks, insert the
4009 -- conditional further out.
4011 if Analyzed
(P
) then
4014 -- Actions belong to the then expression, temporarily place
4015 -- them as Then_Actions of the if expression. They will be
4016 -- moved to the proper place later when the if expression
4019 elsif N
= ThenX
then
4020 if Present
(Then_Actions
(P
)) then
4021 Insert_List_After_And_Analyze
4022 (Last
(Then_Actions
(P
)), Ins_Actions
);
4024 Set_Then_Actions
(P
, Ins_Actions
);
4025 Analyze_List
(Then_Actions
(P
));
4030 -- Actions belong to the else expression, temporarily place
4031 -- them as Else_Actions of the if expression. They will be
4032 -- moved to the proper place later when the if expression
4035 elsif N
= ElseX
then
4036 if Present
(Else_Actions
(P
)) then
4037 Insert_List_After_And_Analyze
4038 (Last
(Else_Actions
(P
)), Ins_Actions
);
4040 Set_Else_Actions
(P
, Ins_Actions
);
4041 Analyze_List
(Else_Actions
(P
));
4046 -- Actions belong to the condition. In this case they are
4047 -- unconditionally executed, and so we can continue the
4048 -- search for the proper insert point.
4055 -- Alternative of case expression, we place the action in the
4056 -- Actions field of the case expression alternative, this will
4057 -- be handled when the case expression is expanded.
4059 when N_Case_Expression_Alternative
=>
4060 if Present
(Actions
(P
)) then
4061 Insert_List_After_And_Analyze
4062 (Last
(Actions
(P
)), Ins_Actions
);
4064 Set_Actions
(P
, Ins_Actions
);
4065 Analyze_List
(Actions
(P
));
4070 -- Case of appearing within an Expressions_With_Actions node. When
4071 -- the new actions come from the expression of the expression with
4072 -- actions, they must be added to the existing actions. The other
4073 -- alternative is when the new actions are related to one of the
4074 -- existing actions of the expression with actions, and should
4075 -- never reach here: if actions are inserted on a statement
4076 -- within the Actions of an expression with actions, or on some
4077 -- sub-expression of such a statement, then the outermost proper
4078 -- insertion point is right before the statement, and we should
4079 -- never climb up as far as the N_Expression_With_Actions itself.
4081 when N_Expression_With_Actions
=>
4082 if N
= Expression
(P
) then
4083 if Is_Empty_List
(Actions
(P
)) then
4084 Append_List_To
(Actions
(P
), Ins_Actions
);
4085 Analyze_List
(Actions
(P
));
4087 Insert_List_After_And_Analyze
4088 (Last
(Actions
(P
)), Ins_Actions
);
4094 raise Program_Error
;
4097 -- Case of appearing in the condition of a while expression or
4098 -- elsif. We insert the actions into the Condition_Actions field.
4099 -- They will be moved further out when the while loop or elsif
4102 when N_Iteration_Scheme |
4105 if N
= Condition
(P
) then
4106 if Present
(Condition_Actions
(P
)) then
4107 Insert_List_After_And_Analyze
4108 (Last
(Condition_Actions
(P
)), Ins_Actions
);
4110 Set_Condition_Actions
(P
, Ins_Actions
);
4112 -- Set the parent of the insert actions explicitly. This
4113 -- is not a syntactic field, but we need the parent field
4114 -- set, in particular so that freeze can understand that
4115 -- it is dealing with condition actions, and properly
4116 -- insert the freezing actions.
4118 Set_Parent
(Ins_Actions
, P
);
4119 Analyze_List
(Condition_Actions
(P
));
4125 -- Statements, declarations, pragmas, representation clauses
4130 N_Procedure_Call_Statement |
4131 N_Statement_Other_Than_Procedure_Call |
4137 -- Representation_Clause
4140 N_Attribute_Definition_Clause |
4141 N_Enumeration_Representation_Clause |
4142 N_Record_Representation_Clause |
4146 N_Abstract_Subprogram_Declaration |
4148 N_Exception_Declaration |
4149 N_Exception_Renaming_Declaration |
4150 N_Expression_Function |
4151 N_Formal_Abstract_Subprogram_Declaration |
4152 N_Formal_Concrete_Subprogram_Declaration |
4153 N_Formal_Object_Declaration |
4154 N_Formal_Type_Declaration |
4155 N_Full_Type_Declaration |
4156 N_Function_Instantiation |
4157 N_Generic_Function_Renaming_Declaration |
4158 N_Generic_Package_Declaration |
4159 N_Generic_Package_Renaming_Declaration |
4160 N_Generic_Procedure_Renaming_Declaration |
4161 N_Generic_Subprogram_Declaration |
4162 N_Implicit_Label_Declaration |
4163 N_Incomplete_Type_Declaration |
4164 N_Number_Declaration |
4165 N_Object_Declaration |
4166 N_Object_Renaming_Declaration |
4168 N_Package_Body_Stub |
4169 N_Package_Declaration |
4170 N_Package_Instantiation |
4171 N_Package_Renaming_Declaration |
4172 N_Private_Extension_Declaration |
4173 N_Private_Type_Declaration |
4174 N_Procedure_Instantiation |
4176 N_Protected_Body_Stub |
4177 N_Protected_Type_Declaration |
4178 N_Single_Task_Declaration |
4180 N_Subprogram_Body_Stub |
4181 N_Subprogram_Declaration |
4182 N_Subprogram_Renaming_Declaration |
4183 N_Subtype_Declaration |
4186 N_Task_Type_Declaration |
4188 -- Use clauses can appear in lists of declarations
4190 N_Use_Package_Clause |
4193 -- Freeze entity behaves like a declaration or statement
4196 N_Freeze_Generic_Entity
4198 -- Do not insert here if the item is not a list member (this
4199 -- happens for example with a triggering statement, and the
4200 -- proper approach is to insert before the entire select).
4202 if not Is_List_Member
(P
) then
4205 -- Do not insert if parent of P is an N_Component_Association
4206 -- node (i.e. we are in the context of an N_Aggregate or
4207 -- N_Extension_Aggregate node. In this case we want to insert
4208 -- before the entire aggregate.
4210 elsif Nkind
(Parent
(P
)) = N_Component_Association
then
4213 -- Do not insert if the parent of P is either an N_Variant node
4214 -- or an N_Record_Definition node, meaning in either case that
4215 -- P is a member of a component list, and that therefore the
4216 -- actions should be inserted outside the complete record
4219 elsif Nkind_In
(Parent
(P
), N_Variant
, N_Record_Definition
) then
4222 -- Do not insert freeze nodes within the loop generated for
4223 -- an aggregate, because they may be elaborated too late for
4224 -- subsequent use in the back end: within a package spec the
4225 -- loop is part of the elaboration procedure and is only
4226 -- elaborated during the second pass.
4228 -- If the loop comes from source, or the entity is local to the
4229 -- loop itself it must remain within.
4231 elsif Nkind
(Parent
(P
)) = N_Loop_Statement
4232 and then not Comes_From_Source
(Parent
(P
))
4233 and then Nkind
(First
(Ins_Actions
)) = N_Freeze_Entity
4235 Scope
(Entity
(First
(Ins_Actions
))) /= Current_Scope
4239 -- Otherwise we can go ahead and do the insertion
4241 elsif P
= Wrapped_Node
then
4242 Store_Before_Actions_In_Scope
(Ins_Actions
);
4246 Insert_List_Before_And_Analyze
(P
, Ins_Actions
);
4250 -- A special case, N_Raise_xxx_Error can act either as a statement
4251 -- or a subexpression. We tell the difference by looking at the
4252 -- Etype. It is set to Standard_Void_Type in the statement case.
4255 N_Raise_xxx_Error
=>
4256 if Etype
(P
) = Standard_Void_Type
then
4257 if P
= Wrapped_Node
then
4258 Store_Before_Actions_In_Scope
(Ins_Actions
);
4260 Insert_List_Before_And_Analyze
(P
, Ins_Actions
);
4265 -- In the subexpression case, keep climbing
4271 -- If a component association appears within a loop created for
4272 -- an array aggregate, attach the actions to the association so
4273 -- they can be subsequently inserted within the loop. For other
4274 -- component associations insert outside of the aggregate. For
4275 -- an association that will generate a loop, its Loop_Actions
4276 -- attribute is already initialized (see exp_aggr.adb).
4278 -- The list of loop_actions can in turn generate additional ones,
4279 -- that are inserted before the associated node. If the associated
4280 -- node is outside the aggregate, the new actions are collected
4281 -- at the end of the loop actions, to respect the order in which
4282 -- they are to be elaborated.
4285 N_Component_Association
=>
4286 if Nkind
(Parent
(P
)) = N_Aggregate
4287 and then Present
(Loop_Actions
(P
))
4289 if Is_Empty_List
(Loop_Actions
(P
)) then
4290 Set_Loop_Actions
(P
, Ins_Actions
);
4291 Analyze_List
(Ins_Actions
);
4298 -- Check whether these actions were generated by a
4299 -- declaration that is part of the loop_ actions
4300 -- for the component_association.
4303 while Present
(Decl
) loop
4304 exit when Parent
(Decl
) = P
4305 and then Is_List_Member
(Decl
)
4307 List_Containing
(Decl
) = Loop_Actions
(P
);
4308 Decl
:= Parent
(Decl
);
4311 if Present
(Decl
) then
4312 Insert_List_Before_And_Analyze
4313 (Decl
, Ins_Actions
);
4315 Insert_List_After_And_Analyze
4316 (Last
(Loop_Actions
(P
)), Ins_Actions
);
4327 -- Another special case, an attribute denoting a procedure call
4330 N_Attribute_Reference
=>
4331 if Is_Procedure_Attribute_Name
(Attribute_Name
(P
)) then
4332 if P
= Wrapped_Node
then
4333 Store_Before_Actions_In_Scope
(Ins_Actions
);
4335 Insert_List_Before_And_Analyze
(P
, Ins_Actions
);
4340 -- In the subexpression case, keep climbing
4346 -- A contract node should not belong to the tree
4349 raise Program_Error
;
4351 -- For all other node types, keep climbing tree
4355 N_Accept_Alternative |
4356 N_Access_Definition |
4357 N_Access_Function_Definition |
4358 N_Access_Procedure_Definition |
4359 N_Access_To_Object_Definition |
4362 N_Aspect_Specification |
4364 N_Case_Statement_Alternative |
4365 N_Character_Literal |
4366 N_Compilation_Unit |
4367 N_Compilation_Unit_Aux |
4368 N_Component_Clause |
4369 N_Component_Declaration |
4370 N_Component_Definition |
4372 N_Constrained_Array_Definition |
4373 N_Decimal_Fixed_Point_Definition |
4374 N_Defining_Character_Literal |
4375 N_Defining_Identifier |
4376 N_Defining_Operator_Symbol |
4377 N_Defining_Program_Unit_Name |
4378 N_Delay_Alternative |
4379 N_Delta_Constraint |
4380 N_Derived_Type_Definition |
4382 N_Digits_Constraint |
4383 N_Discriminant_Association |
4384 N_Discriminant_Specification |
4386 N_Entry_Body_Formal_Part |
4387 N_Entry_Call_Alternative |
4388 N_Entry_Declaration |
4389 N_Entry_Index_Specification |
4390 N_Enumeration_Type_Definition |
4392 N_Exception_Handler |
4394 N_Explicit_Dereference |
4395 N_Extension_Aggregate |
4396 N_Floating_Point_Definition |
4397 N_Formal_Decimal_Fixed_Point_Definition |
4398 N_Formal_Derived_Type_Definition |
4399 N_Formal_Discrete_Type_Definition |
4400 N_Formal_Floating_Point_Definition |
4401 N_Formal_Modular_Type_Definition |
4402 N_Formal_Ordinary_Fixed_Point_Definition |
4403 N_Formal_Package_Declaration |
4404 N_Formal_Private_Type_Definition |
4405 N_Formal_Incomplete_Type_Definition |
4406 N_Formal_Signed_Integer_Type_Definition |
4408 N_Function_Specification |
4409 N_Generic_Association |
4410 N_Handled_Sequence_Of_Statements |
4413 N_Index_Or_Discriminant_Constraint |
4414 N_Indexed_Component |
4416 N_Iterator_Specification |
4419 N_Loop_Parameter_Specification |
4421 N_Modular_Type_Definition |
4447 N_Op_Shift_Right_Arithmetic |
4451 N_Ordinary_Fixed_Point_Definition |
4453 N_Package_Specification |
4454 N_Parameter_Association |
4455 N_Parameter_Specification |
4456 N_Pop_Constraint_Error_Label |
4457 N_Pop_Program_Error_Label |
4458 N_Pop_Storage_Error_Label |
4459 N_Pragma_Argument_Association |
4460 N_Procedure_Specification |
4461 N_Protected_Definition |
4462 N_Push_Constraint_Error_Label |
4463 N_Push_Program_Error_Label |
4464 N_Push_Storage_Error_Label |
4465 N_Qualified_Expression |
4466 N_Quantified_Expression |
4467 N_Raise_Expression |
4469 N_Range_Constraint |
4471 N_Real_Range_Specification |
4472 N_Record_Definition |
4474 N_SCIL_Dispatch_Table_Tag_Init |
4475 N_SCIL_Dispatching_Call |
4476 N_SCIL_Membership_Test |
4477 N_Selected_Component |
4478 N_Signed_Integer_Type_Definition |
4479 N_Single_Protected_Declaration |
4482 N_Subtype_Indication |
4485 N_Terminate_Alternative |
4486 N_Triggering_Alternative |
4488 N_Unchecked_Expression |
4489 N_Unchecked_Type_Conversion |
4490 N_Unconstrained_Array_Definition |
4495 N_Validate_Unchecked_Conversion |
4502 -- If we fall through above tests, keep climbing tree
4506 if Nkind
(Parent
(N
)) = N_Subunit
then
4508 -- This is the proper body corresponding to a stub. Insertion must
4509 -- be done at the point of the stub, which is in the declarative
4510 -- part of the parent unit.
4512 P
:= Corresponding_Stub
(Parent
(N
));
4520 -- Version with check(s) suppressed
4522 procedure Insert_Actions
4523 (Assoc_Node
: Node_Id
;
4524 Ins_Actions
: List_Id
;
4525 Suppress
: Check_Id
)
4528 if Suppress
= All_Checks
then
4530 Sva
: constant Suppress_Array
:= Scope_Suppress
.Suppress
;
4532 Scope_Suppress
.Suppress
:= (others => True);
4533 Insert_Actions
(Assoc_Node
, Ins_Actions
);
4534 Scope_Suppress
.Suppress
:= Sva
;
4539 Svg
: constant Boolean := Scope_Suppress
.Suppress
(Suppress
);
4541 Scope_Suppress
.Suppress
(Suppress
) := True;
4542 Insert_Actions
(Assoc_Node
, Ins_Actions
);
4543 Scope_Suppress
.Suppress
(Suppress
) := Svg
;
4548 --------------------------
4549 -- Insert_Actions_After --
4550 --------------------------
4552 procedure Insert_Actions_After
4553 (Assoc_Node
: Node_Id
;
4554 Ins_Actions
: List_Id
)
4557 if Scope_Is_Transient
and then Assoc_Node
= Node_To_Be_Wrapped
then
4558 Store_After_Actions_In_Scope
(Ins_Actions
);
4560 Insert_List_After_And_Analyze
(Assoc_Node
, Ins_Actions
);
4562 end Insert_Actions_After
;
4564 ------------------------
4565 -- Insert_Declaration --
4566 ------------------------
4568 procedure Insert_Declaration
(N
: Node_Id
; Decl
: Node_Id
) is
4572 pragma Assert
(Nkind
(N
) in N_Subexpr
);
4574 -- Climb until we find a procedure or a package
4578 pragma Assert
(Present
(Parent
(P
)));
4581 if Is_List_Member
(P
) then
4582 exit when Nkind_In
(Parent
(P
), N_Package_Specification
,
4585 -- Special handling for handled sequence of statements, we must
4586 -- insert in the statements not the exception handlers!
4588 if Nkind
(Parent
(P
)) = N_Handled_Sequence_Of_Statements
then
4589 P
:= First
(Statements
(Parent
(P
)));
4595 -- Now do the insertion
4597 Insert_Before
(P
, Decl
);
4599 end Insert_Declaration
;
4601 ---------------------------------
4602 -- Insert_Library_Level_Action --
4603 ---------------------------------
4605 procedure Insert_Library_Level_Action
(N
: Node_Id
) is
4606 Aux
: constant Node_Id
:= Aux_Decls_Node
(Cunit
(Main_Unit
));
4609 Push_Scope
(Cunit_Entity
(Main_Unit
));
4610 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
4612 if No
(Actions
(Aux
)) then
4613 Set_Actions
(Aux
, New_List
(N
));
4615 Append
(N
, Actions
(Aux
));
4620 end Insert_Library_Level_Action
;
4622 ----------------------------------
4623 -- Insert_Library_Level_Actions --
4624 ----------------------------------
4626 procedure Insert_Library_Level_Actions
(L
: List_Id
) is
4627 Aux
: constant Node_Id
:= Aux_Decls_Node
(Cunit
(Main_Unit
));
4630 if Is_Non_Empty_List
(L
) then
4631 Push_Scope
(Cunit_Entity
(Main_Unit
));
4632 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
4634 if No
(Actions
(Aux
)) then
4635 Set_Actions
(Aux
, L
);
4638 Insert_List_After_And_Analyze
(Last
(Actions
(Aux
)), L
);
4643 end Insert_Library_Level_Actions
;
4645 ----------------------
4646 -- Inside_Init_Proc --
4647 ----------------------
4649 function Inside_Init_Proc
return Boolean is
4654 while Present
(S
) and then S
/= Standard_Standard
loop
4655 if Is_Init_Proc
(S
) then
4663 end Inside_Init_Proc
;
4665 ----------------------------
4666 -- Is_All_Null_Statements --
4667 ----------------------------
4669 function Is_All_Null_Statements
(L
: List_Id
) return Boolean is
4674 while Present
(Stm
) loop
4675 if Nkind
(Stm
) /= N_Null_Statement
then
4683 end Is_All_Null_Statements
;
4685 --------------------------------------------------
4686 -- Is_Displacement_Of_Object_Or_Function_Result --
4687 --------------------------------------------------
4689 function Is_Displacement_Of_Object_Or_Function_Result
4690 (Obj_Id
: Entity_Id
) return Boolean
4692 function Is_Controlled_Function_Call
(N
: Node_Id
) return Boolean;
4693 -- Determine if particular node denotes a controlled function call. The
4694 -- call may have been heavily expanded.
4696 function Is_Displace_Call
(N
: Node_Id
) return Boolean;
4697 -- Determine whether a particular node is a call to Ada.Tags.Displace.
4698 -- The call might be nested within other actions such as conversions.
4700 function Is_Source_Object
(N
: Node_Id
) return Boolean;
4701 -- Determine whether a particular node denotes a source object
4703 ---------------------------------
4704 -- Is_Controlled_Function_Call --
4705 ---------------------------------
4707 function Is_Controlled_Function_Call
(N
: Node_Id
) return Boolean is
4708 Expr
: Node_Id
:= Original_Node
(N
);
4711 if Nkind
(Expr
) = N_Function_Call
then
4712 Expr
:= Name
(Expr
);
4714 -- When a function call appears in Object.Operation format, the
4715 -- original representation has two possible forms depending on the
4716 -- availability of actual parameters:
4718 -- Obj.Func_Call N_Selected_Component
4719 -- Obj.Func_Call (Param) N_Indexed_Component
4722 if Nkind
(Expr
) = N_Indexed_Component
then
4723 Expr
:= Prefix
(Expr
);
4726 if Nkind
(Expr
) = N_Selected_Component
then
4727 Expr
:= Selector_Name
(Expr
);
4732 Nkind_In
(Expr
, N_Expanded_Name
, N_Identifier
)
4733 and then Ekind
(Entity
(Expr
)) = E_Function
4734 and then Needs_Finalization
(Etype
(Entity
(Expr
)));
4735 end Is_Controlled_Function_Call
;
4737 ----------------------
4738 -- Is_Displace_Call --
4739 ----------------------
4741 function Is_Displace_Call
(N
: Node_Id
) return Boolean is
4742 Call
: Node_Id
:= N
;
4745 -- Strip various actions which may precede a call to Displace
4748 if Nkind
(Call
) = N_Explicit_Dereference
then
4749 Call
:= Prefix
(Call
);
4751 elsif Nkind_In
(Call
, N_Type_Conversion
,
4752 N_Unchecked_Type_Conversion
)
4754 Call
:= Expression
(Call
);
4763 and then Nkind
(Call
) = N_Function_Call
4764 and then Is_RTE
(Entity
(Name
(Call
)), RE_Displace
);
4765 end Is_Displace_Call
;
4767 ----------------------
4768 -- Is_Source_Object --
4769 ----------------------
4771 function Is_Source_Object
(N
: Node_Id
) return Boolean is
4775 and then Nkind
(N
) in N_Has_Entity
4776 and then Is_Object
(Entity
(N
))
4777 and then Comes_From_Source
(N
);
4778 end Is_Source_Object
;
4782 Decl
: constant Node_Id
:= Parent
(Obj_Id
);
4783 Obj_Typ
: constant Entity_Id
:= Base_Type
(Etype
(Obj_Id
));
4784 Orig_Decl
: constant Node_Id
:= Original_Node
(Decl
);
4786 -- Start of processing for Is_Displacement_Of_Object_Or_Function_Result
4791 -- Obj : CW_Type := Function_Call (...);
4795 -- Tmp : ... := Function_Call (...)'reference;
4796 -- Obj : CW_Type renames (... Ada.Tags.Displace (Tmp));
4798 -- where the return type of the function and the class-wide type require
4799 -- dispatch table pointer displacement.
4803 -- Obj : CW_Type := Src_Obj;
4807 -- Obj : CW_Type renames (... Ada.Tags.Displace (Src_Obj));
4809 -- where the type of the source object and the class-wide type require
4810 -- dispatch table pointer displacement.
4813 Nkind
(Decl
) = N_Object_Renaming_Declaration
4814 and then Nkind
(Orig_Decl
) = N_Object_Declaration
4815 and then Comes_From_Source
(Orig_Decl
)
4816 and then Is_Class_Wide_Type
(Obj_Typ
)
4817 and then Is_Displace_Call
(Renamed_Object
(Obj_Id
))
4819 (Is_Controlled_Function_Call
(Expression
(Orig_Decl
))
4820 or else Is_Source_Object
(Expression
(Orig_Decl
)));
4821 end Is_Displacement_Of_Object_Or_Function_Result
;
4823 ------------------------------
4824 -- Is_Finalizable_Transient --
4825 ------------------------------
4827 function Is_Finalizable_Transient
4829 Rel_Node
: Node_Id
) return Boolean
4831 Obj_Id
: constant Entity_Id
:= Defining_Identifier
(Decl
);
4832 Obj_Typ
: constant Entity_Id
:= Base_Type
(Etype
(Obj_Id
));
4834 function Initialized_By_Access
(Trans_Id
: Entity_Id
) return Boolean;
4835 -- Determine whether transient object Trans_Id is initialized either
4836 -- by a function call which returns an access type or simply renames
4839 function Initialized_By_Aliased_BIP_Func_Call
4840 (Trans_Id
: Entity_Id
) return Boolean;
4841 -- Determine whether transient object Trans_Id is initialized by a
4842 -- build-in-place function call where the BIPalloc parameter is of
4843 -- value 1 and BIPaccess is not null. This case creates an aliasing
4844 -- between the returned value and the value denoted by BIPaccess.
4847 (Trans_Id
: Entity_Id
;
4848 First_Stmt
: Node_Id
) return Boolean;
4849 -- Determine whether transient object Trans_Id has been renamed or
4850 -- aliased through 'reference in the statement list starting from
4853 function Is_Allocated
(Trans_Id
: Entity_Id
) return Boolean;
4854 -- Determine whether transient object Trans_Id is allocated on the heap
4856 function Is_Iterated_Container
4857 (Trans_Id
: Entity_Id
;
4858 First_Stmt
: Node_Id
) return Boolean;
4859 -- Determine whether transient object Trans_Id denotes a container which
4860 -- is in the process of being iterated in the statement list starting
4863 ---------------------------
4864 -- Initialized_By_Access --
4865 ---------------------------
4867 function Initialized_By_Access
(Trans_Id
: Entity_Id
) return Boolean is
4868 Expr
: constant Node_Id
:= Expression
(Parent
(Trans_Id
));
4873 and then Nkind
(Expr
) /= N_Reference
4874 and then Is_Access_Type
(Etype
(Expr
));
4875 end Initialized_By_Access
;
4877 ------------------------------------------
4878 -- Initialized_By_Aliased_BIP_Func_Call --
4879 ------------------------------------------
4881 function Initialized_By_Aliased_BIP_Func_Call
4882 (Trans_Id
: Entity_Id
) return Boolean
4884 Call
: Node_Id
:= Expression
(Parent
(Trans_Id
));
4887 -- Build-in-place calls usually appear in 'reference format
4889 if Nkind
(Call
) = N_Reference
then
4890 Call
:= Prefix
(Call
);
4893 if Is_Build_In_Place_Function_Call
(Call
) then
4895 Access_Nam
: Name_Id
:= No_Name
;
4896 Access_OK
: Boolean := False;
4898 Alloc_Nam
: Name_Id
:= No_Name
;
4899 Alloc_OK
: Boolean := False;
4901 Func_Id
: Entity_Id
;
4905 -- Examine all parameter associations of the function call
4907 Param
:= First
(Parameter_Associations
(Call
));
4908 while Present
(Param
) loop
4909 if Nkind
(Param
) = N_Parameter_Association
4910 and then Nkind
(Selector_Name
(Param
)) = N_Identifier
4912 Actual
:= Explicit_Actual_Parameter
(Param
);
4913 Formal
:= Selector_Name
(Param
);
4915 -- Construct the names of formals BIPaccess and BIPalloc
4916 -- using the function name retrieved from an arbitrary
4919 if Access_Nam
= No_Name
4920 and then Alloc_Nam
= No_Name
4921 and then Present
(Entity
(Formal
))
4923 Func_Id
:= Scope
(Entity
(Formal
));
4926 New_External_Name
(Chars
(Func_Id
),
4927 BIP_Formal_Suffix
(BIP_Object_Access
));
4930 New_External_Name
(Chars
(Func_Id
),
4931 BIP_Formal_Suffix
(BIP_Alloc_Form
));
4934 -- A match for BIPaccess => Temp has been found
4936 if Chars
(Formal
) = Access_Nam
4937 and then Nkind
(Actual
) /= N_Null
4942 -- A match for BIPalloc => 1 has been found
4944 if Chars
(Formal
) = Alloc_Nam
4945 and then Nkind
(Actual
) = N_Integer_Literal
4946 and then Intval
(Actual
) = Uint_1
4955 return Access_OK
and Alloc_OK
;
4960 end Initialized_By_Aliased_BIP_Func_Call
;
4967 (Trans_Id
: Entity_Id
;
4968 First_Stmt
: Node_Id
) return Boolean
4970 function Find_Renamed_Object
(Ren_Decl
: Node_Id
) return Entity_Id
;
4971 -- Given an object renaming declaration, retrieve the entity of the
4972 -- renamed name. Return Empty if the renamed name is anything other
4973 -- than a variable or a constant.
4975 -------------------------
4976 -- Find_Renamed_Object --
4977 -------------------------
4979 function Find_Renamed_Object
(Ren_Decl
: Node_Id
) return Entity_Id
is
4980 Ren_Obj
: Node_Id
:= Empty
;
4982 function Find_Object
(N
: Node_Id
) return Traverse_Result
;
4983 -- Try to detect an object which is either a constant or a
4990 function Find_Object
(N
: Node_Id
) return Traverse_Result
is
4992 -- Stop the search once a constant or a variable has been
4995 if Nkind
(N
) = N_Identifier
4996 and then Present
(Entity
(N
))
4997 and then Ekind_In
(Entity
(N
), E_Constant
, E_Variable
)
4999 Ren_Obj
:= Entity
(N
);
5006 procedure Search
is new Traverse_Proc
(Find_Object
);
5010 Typ
: constant Entity_Id
:= Etype
(Defining_Identifier
(Ren_Decl
));
5012 -- Start of processing for Find_Renamed_Object
5015 -- Actions related to dispatching calls may appear as renamings of
5016 -- tags. Do not process this type of renaming because it does not
5017 -- use the actual value of the object.
5019 if not Is_RTE
(Typ
, RE_Tag_Ptr
) then
5020 Search
(Name
(Ren_Decl
));
5024 end Find_Renamed_Object
;
5029 Ren_Obj
: Entity_Id
;
5032 -- Start of processing for Is_Aliased
5035 -- A controlled transient object is not considered aliased when it
5036 -- appears inside an expression_with_actions node even when there are
5037 -- explicit aliases of it:
5040 -- Trans_Id : Ctrl_Typ ...; -- controlled transient object
5041 -- Alias : ... := Trans_Id; -- object is aliased
5042 -- Val : constant Boolean :=
5043 -- ... Alias ...; -- aliasing ends
5044 -- <finalize Trans_Id> -- object safe to finalize
5047 -- Expansion ensures that all aliases are encapsulated in the actions
5048 -- list and do not leak to the expression by forcing the evaluation
5049 -- of the expression.
5051 if Nkind
(Rel_Node
) = N_Expression_With_Actions
then
5054 -- Otherwise examine the statements after the controlled transient
5055 -- object and look for various forms of aliasing.
5059 while Present
(Stmt
) loop
5060 if Nkind
(Stmt
) = N_Object_Declaration
then
5061 Expr
:= Expression
(Stmt
);
5063 -- Aliasing of the form:
5064 -- Obj : ... := Trans_Id'reference;
5067 and then Nkind
(Expr
) = N_Reference
5068 and then Nkind
(Prefix
(Expr
)) = N_Identifier
5069 and then Entity
(Prefix
(Expr
)) = Trans_Id
5074 elsif Nkind
(Stmt
) = N_Object_Renaming_Declaration
then
5075 Ren_Obj
:= Find_Renamed_Object
(Stmt
);
5077 -- Aliasing of the form:
5078 -- Obj : ... renames ... Trans_Id ...;
5080 if Present
(Ren_Obj
) and then Ren_Obj
= Trans_Id
then
5096 function Is_Allocated
(Trans_Id
: Entity_Id
) return Boolean is
5097 Expr
: constant Node_Id
:= Expression
(Parent
(Trans_Id
));
5100 Is_Access_Type
(Etype
(Trans_Id
))
5101 and then Present
(Expr
)
5102 and then Nkind
(Expr
) = N_Allocator
;
5105 ---------------------------
5106 -- Is_Iterated_Container --
5107 ---------------------------
5109 function Is_Iterated_Container
5110 (Trans_Id
: Entity_Id
;
5111 First_Stmt
: Node_Id
) return Boolean
5121 -- It is not possible to iterate over containers in non-Ada 2012 code
5123 if Ada_Version
< Ada_2012
then
5127 Typ
:= Etype
(Trans_Id
);
5129 -- Handle access type created for secondary stack use
5131 if Is_Access_Type
(Typ
) then
5132 Typ
:= Designated_Type
(Typ
);
5135 -- Look for aspect Default_Iterator. It may be part of a type
5136 -- declaration for a container, or inherited from a base type
5139 Aspect
:= Find_Value_Of_Aspect
(Typ
, Aspect_Default_Iterator
);
5141 if Present
(Aspect
) then
5142 Iter
:= Entity
(Aspect
);
5144 -- Examine the statements following the container object and
5145 -- look for a call to the default iterate routine where the
5146 -- first parameter is the transient. Such a call appears as:
5148 -- It : Access_To_CW_Iterator :=
5149 -- Iterate (Tran_Id.all, ...)'reference;
5152 while Present
(Stmt
) loop
5154 -- Detect an object declaration which is initialized by a
5155 -- secondary stack function call.
5157 if Nkind
(Stmt
) = N_Object_Declaration
5158 and then Present
(Expression
(Stmt
))
5159 and then Nkind
(Expression
(Stmt
)) = N_Reference
5160 and then Nkind
(Prefix
(Expression
(Stmt
))) = N_Function_Call
5162 Call
:= Prefix
(Expression
(Stmt
));
5164 -- The call must invoke the default iterate routine of
5165 -- the container and the transient object must appear as
5166 -- the first actual parameter. Skip any calls whose names
5167 -- are not entities.
5169 if Is_Entity_Name
(Name
(Call
))
5170 and then Entity
(Name
(Call
)) = Iter
5171 and then Present
(Parameter_Associations
(Call
))
5173 Param
:= First
(Parameter_Associations
(Call
));
5175 if Nkind
(Param
) = N_Explicit_Dereference
5176 and then Entity
(Prefix
(Param
)) = Trans_Id
5188 end Is_Iterated_Container
;
5192 Desig
: Entity_Id
:= Obj_Typ
;
5194 -- Start of processing for Is_Finalizable_Transient
5197 -- Handle access types
5199 if Is_Access_Type
(Desig
) then
5200 Desig
:= Available_View
(Designated_Type
(Desig
));
5204 Ekind_In
(Obj_Id
, E_Constant
, E_Variable
)
5205 and then Needs_Finalization
(Desig
)
5206 and then Requires_Transient_Scope
(Desig
)
5207 and then Nkind
(Rel_Node
) /= N_Simple_Return_Statement
5209 -- Do not consider renamed or 'reference-d transient objects because
5210 -- the act of renaming extends the object's lifetime.
5212 and then not Is_Aliased
(Obj_Id
, Decl
)
5214 -- Do not consider transient objects allocated on the heap since
5215 -- they are attached to a finalization master.
5217 and then not Is_Allocated
(Obj_Id
)
5219 -- If the transient object is a pointer, check that it is not
5220 -- initialized by a function that returns a pointer or acts as a
5221 -- renaming of another pointer.
5224 (not Is_Access_Type
(Obj_Typ
)
5225 or else not Initialized_By_Access
(Obj_Id
))
5227 -- Do not consider transient objects which act as indirect aliases
5228 -- of build-in-place function results.
5230 and then not Initialized_By_Aliased_BIP_Func_Call
(Obj_Id
)
5232 -- Do not consider conversions of tags to class-wide types
5234 and then not Is_Tag_To_Class_Wide_Conversion
(Obj_Id
)
5236 -- Do not consider iterators because those are treated as normal
5237 -- controlled objects and are processed by the usual finalization
5238 -- machinery. This avoids the double finalization of an iterator.
5240 and then not Is_Iterator
(Desig
)
5242 -- Do not consider containers in the context of iterator loops. Such
5243 -- transient objects must exist for as long as the loop is around,
5244 -- otherwise any operation carried out by the iterator will fail.
5246 and then not Is_Iterated_Container
(Obj_Id
, Decl
);
5247 end Is_Finalizable_Transient
;
5249 ---------------------------------
5250 -- Is_Fully_Repped_Tagged_Type --
5251 ---------------------------------
5253 function Is_Fully_Repped_Tagged_Type
(T
: Entity_Id
) return Boolean is
5254 U
: constant Entity_Id
:= Underlying_Type
(T
);
5258 if No
(U
) or else not Is_Tagged_Type
(U
) then
5260 elsif Has_Discriminants
(U
) then
5262 elsif not Has_Specified_Layout
(U
) then
5266 -- Here we have a tagged type, see if it has any unlayed out fields
5267 -- other than a possible tag and parent fields. If so, we return False.
5269 Comp
:= First_Component
(U
);
5270 while Present
(Comp
) loop
5271 if not Is_Tag
(Comp
)
5272 and then Chars
(Comp
) /= Name_uParent
5273 and then No
(Component_Clause
(Comp
))
5277 Next_Component
(Comp
);
5281 -- All components are layed out
5284 end Is_Fully_Repped_Tagged_Type
;
5286 ----------------------------------
5287 -- Is_Library_Level_Tagged_Type --
5288 ----------------------------------
5290 function Is_Library_Level_Tagged_Type
(Typ
: Entity_Id
) return Boolean is
5292 return Is_Tagged_Type
(Typ
) and then Is_Library_Level_Entity
(Typ
);
5293 end Is_Library_Level_Tagged_Type
;
5295 --------------------------
5296 -- Is_Non_BIP_Func_Call --
5297 --------------------------
5299 function Is_Non_BIP_Func_Call
(Expr
: Node_Id
) return Boolean is
5301 -- The expected call is of the format
5303 -- Func_Call'reference
5306 Nkind
(Expr
) = N_Reference
5307 and then Nkind
(Prefix
(Expr
)) = N_Function_Call
5308 and then not Is_Build_In_Place_Function_Call
(Prefix
(Expr
));
5309 end Is_Non_BIP_Func_Call
;
5311 ------------------------------------
5312 -- Is_Object_Access_BIP_Func_Call --
5313 ------------------------------------
5315 function Is_Object_Access_BIP_Func_Call
5317 Obj_Id
: Entity_Id
) return Boolean
5319 Access_Nam
: Name_Id
:= No_Name
;
5326 -- Build-in-place calls usually appear in 'reference format. Note that
5327 -- the accessibility check machinery may add an extra 'reference due to
5328 -- side effect removal.
5331 while Nkind
(Call
) = N_Reference
loop
5332 Call
:= Prefix
(Call
);
5335 if Nkind_In
(Call
, N_Qualified_Expression
,
5336 N_Unchecked_Type_Conversion
)
5338 Call
:= Expression
(Call
);
5341 if Is_Build_In_Place_Function_Call
(Call
) then
5343 -- Examine all parameter associations of the function call
5345 Param
:= First
(Parameter_Associations
(Call
));
5346 while Present
(Param
) loop
5347 if Nkind
(Param
) = N_Parameter_Association
5348 and then Nkind
(Selector_Name
(Param
)) = N_Identifier
5350 Formal
:= Selector_Name
(Param
);
5351 Actual
:= Explicit_Actual_Parameter
(Param
);
5353 -- Construct the name of formal BIPaccess. It is much easier to
5354 -- extract the name of the function using an arbitrary formal's
5355 -- scope rather than the Name field of Call.
5357 if Access_Nam
= No_Name
and then Present
(Entity
(Formal
)) then
5360 (Chars
(Scope
(Entity
(Formal
))),
5361 BIP_Formal_Suffix
(BIP_Object_Access
));
5364 -- A match for BIPaccess => Obj_Id'Unrestricted_Access has been
5367 if Chars
(Formal
) = Access_Nam
5368 and then Nkind
(Actual
) = N_Attribute_Reference
5369 and then Attribute_Name
(Actual
) = Name_Unrestricted_Access
5370 and then Nkind
(Prefix
(Actual
)) = N_Identifier
5371 and then Entity
(Prefix
(Actual
)) = Obj_Id
5382 end Is_Object_Access_BIP_Func_Call
;
5384 ----------------------------------
5385 -- Is_Possibly_Unaligned_Object --
5386 ----------------------------------
5388 function Is_Possibly_Unaligned_Object
(N
: Node_Id
) return Boolean is
5389 T
: constant Entity_Id
:= Etype
(N
);
5392 -- If renamed object, apply test to underlying object
5394 if Is_Entity_Name
(N
)
5395 and then Is_Object
(Entity
(N
))
5396 and then Present
(Renamed_Object
(Entity
(N
)))
5398 return Is_Possibly_Unaligned_Object
(Renamed_Object
(Entity
(N
)));
5401 -- Tagged and controlled types and aliased types are always aligned, as
5402 -- are concurrent types.
5405 or else Has_Controlled_Component
(T
)
5406 or else Is_Concurrent_Type
(T
)
5407 or else Is_Tagged_Type
(T
)
5408 or else Is_Controlled
(T
)
5413 -- If this is an element of a packed array, may be unaligned
5415 if Is_Ref_To_Bit_Packed_Array
(N
) then
5419 -- Case of indexed component reference: test whether prefix is unaligned
5421 if Nkind
(N
) = N_Indexed_Component
then
5422 return Is_Possibly_Unaligned_Object
(Prefix
(N
));
5424 -- Case of selected component reference
5426 elsif Nkind
(N
) = N_Selected_Component
then
5428 P
: constant Node_Id
:= Prefix
(N
);
5429 C
: constant Entity_Id
:= Entity
(Selector_Name
(N
));
5434 -- If component reference is for an array with non-static bounds,
5435 -- then it is always aligned: we can only process unaligned arrays
5436 -- with static bounds (more precisely compile time known bounds).
5438 if Is_Array_Type
(T
)
5439 and then not Compile_Time_Known_Bounds
(T
)
5444 -- If component is aliased, it is definitely properly aligned
5446 if Is_Aliased
(C
) then
5450 -- If component is for a type implemented as a scalar, and the
5451 -- record is packed, and the component is other than the first
5452 -- component of the record, then the component may be unaligned.
5454 if Is_Packed
(Etype
(P
))
5455 and then Represented_As_Scalar
(Etype
(C
))
5456 and then First_Entity
(Scope
(C
)) /= C
5461 -- Compute maximum possible alignment for T
5463 -- If alignment is known, then that settles things
5465 if Known_Alignment
(T
) then
5466 M
:= UI_To_Int
(Alignment
(T
));
5468 -- If alignment is not known, tentatively set max alignment
5471 M
:= Ttypes
.Maximum_Alignment
;
5473 -- We can reduce this if the Esize is known since the default
5474 -- alignment will never be more than the smallest power of 2
5475 -- that does not exceed this Esize value.
5477 if Known_Esize
(T
) then
5478 S
:= UI_To_Int
(Esize
(T
));
5480 while (M
/ 2) >= S
loop
5486 -- The following code is historical, it used to be present but it
5487 -- is too cautious, because the front-end does not know the proper
5488 -- default alignments for the target. Also, if the alignment is
5489 -- not known, the front end can't know in any case. If a copy is
5490 -- needed, the back-end will take care of it. This whole section
5491 -- including this comment can be removed later ???
5493 -- If the component reference is for a record that has a specified
5494 -- alignment, and we either know it is too small, or cannot tell,
5495 -- then the component may be unaligned.
5497 -- What is the following commented out code ???
5499 -- if Known_Alignment (Etype (P))
5500 -- and then Alignment (Etype (P)) < Ttypes.Maximum_Alignment
5501 -- and then M > Alignment (Etype (P))
5506 -- Case of component clause present which may specify an
5507 -- unaligned position.
5509 if Present
(Component_Clause
(C
)) then
5511 -- Otherwise we can do a test to make sure that the actual
5512 -- start position in the record, and the length, are both
5513 -- consistent with the required alignment. If not, we know
5514 -- that we are unaligned.
5517 Align_In_Bits
: constant Nat
:= M
* System_Storage_Unit
;
5519 if Component_Bit_Offset
(C
) mod Align_In_Bits
/= 0
5520 or else Esize
(C
) mod Align_In_Bits
/= 0
5527 -- Otherwise, for a component reference, test prefix
5529 return Is_Possibly_Unaligned_Object
(P
);
5532 -- If not a component reference, must be aligned
5537 end Is_Possibly_Unaligned_Object
;
5539 ---------------------------------
5540 -- Is_Possibly_Unaligned_Slice --
5541 ---------------------------------
5543 function Is_Possibly_Unaligned_Slice
(N
: Node_Id
) return Boolean is
5545 -- Go to renamed object
5547 if Is_Entity_Name
(N
)
5548 and then Is_Object
(Entity
(N
))
5549 and then Present
(Renamed_Object
(Entity
(N
)))
5551 return Is_Possibly_Unaligned_Slice
(Renamed_Object
(Entity
(N
)));
5554 -- The reference must be a slice
5556 if Nkind
(N
) /= N_Slice
then
5560 -- We only need to worry if the target has strict alignment
5562 if not Target_Strict_Alignment
then
5566 -- If it is a slice, then look at the array type being sliced
5569 Sarr
: constant Node_Id
:= Prefix
(N
);
5570 -- Prefix of the slice, i.e. the array being sliced
5572 Styp
: constant Entity_Id
:= Etype
(Prefix
(N
));
5573 -- Type of the array being sliced
5579 -- The problems arise if the array object that is being sliced
5580 -- is a component of a record or array, and we cannot guarantee
5581 -- the alignment of the array within its containing object.
5583 -- To investigate this, we look at successive prefixes to see
5584 -- if we have a worrisome indexed or selected component.
5588 -- Case of array is part of an indexed component reference
5590 if Nkind
(Pref
) = N_Indexed_Component
then
5591 Ptyp
:= Etype
(Prefix
(Pref
));
5593 -- The only problematic case is when the array is packed, in
5594 -- which case we really know nothing about the alignment of
5595 -- individual components.
5597 if Is_Bit_Packed_Array
(Ptyp
) then
5601 -- Case of array is part of a selected component reference
5603 elsif Nkind
(Pref
) = N_Selected_Component
then
5604 Ptyp
:= Etype
(Prefix
(Pref
));
5606 -- We are definitely in trouble if the record in question
5607 -- has an alignment, and either we know this alignment is
5608 -- inconsistent with the alignment of the slice, or we don't
5609 -- know what the alignment of the slice should be.
5611 if Known_Alignment
(Ptyp
)
5612 and then (Unknown_Alignment
(Styp
)
5613 or else Alignment
(Styp
) > Alignment
(Ptyp
))
5618 -- We are in potential trouble if the record type is packed.
5619 -- We could special case when we know that the array is the
5620 -- first component, but that's not such a simple case ???
5622 if Is_Packed
(Ptyp
) then
5626 -- We are in trouble if there is a component clause, and
5627 -- either we do not know the alignment of the slice, or
5628 -- the alignment of the slice is inconsistent with the
5629 -- bit position specified by the component clause.
5632 Field
: constant Entity_Id
:= Entity
(Selector_Name
(Pref
));
5634 if Present
(Component_Clause
(Field
))
5636 (Unknown_Alignment
(Styp
)
5638 (Component_Bit_Offset
(Field
) mod
5639 (System_Storage_Unit
* Alignment
(Styp
))) /= 0)
5645 -- For cases other than selected or indexed components we know we
5646 -- are OK, since no issues arise over alignment.
5652 -- We processed an indexed component or selected component
5653 -- reference that looked safe, so keep checking prefixes.
5655 Pref
:= Prefix
(Pref
);
5658 end Is_Possibly_Unaligned_Slice
;
5660 -------------------------------
5661 -- Is_Related_To_Func_Return --
5662 -------------------------------
5664 function Is_Related_To_Func_Return
(Id
: Entity_Id
) return Boolean is
5665 Expr
: constant Node_Id
:= Related_Expression
(Id
);
5669 and then Nkind
(Expr
) = N_Explicit_Dereference
5670 and then Nkind
(Parent
(Expr
)) = N_Simple_Return_Statement
;
5671 end Is_Related_To_Func_Return
;
5673 --------------------------------
5674 -- Is_Ref_To_Bit_Packed_Array --
5675 --------------------------------
5677 function Is_Ref_To_Bit_Packed_Array
(N
: Node_Id
) return Boolean is
5682 if Is_Entity_Name
(N
)
5683 and then Is_Object
(Entity
(N
))
5684 and then Present
(Renamed_Object
(Entity
(N
)))
5686 return Is_Ref_To_Bit_Packed_Array
(Renamed_Object
(Entity
(N
)));
5689 if Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
5690 if Is_Bit_Packed_Array
(Etype
(Prefix
(N
))) then
5693 Result
:= Is_Ref_To_Bit_Packed_Array
(Prefix
(N
));
5696 if Result
and then Nkind
(N
) = N_Indexed_Component
then
5697 Expr
:= First
(Expressions
(N
));
5698 while Present
(Expr
) loop
5699 Force_Evaluation
(Expr
);
5709 end Is_Ref_To_Bit_Packed_Array
;
5711 --------------------------------
5712 -- Is_Ref_To_Bit_Packed_Slice --
5713 --------------------------------
5715 function Is_Ref_To_Bit_Packed_Slice
(N
: Node_Id
) return Boolean is
5717 if Nkind
(N
) = N_Type_Conversion
then
5718 return Is_Ref_To_Bit_Packed_Slice
(Expression
(N
));
5720 elsif Is_Entity_Name
(N
)
5721 and then Is_Object
(Entity
(N
))
5722 and then Present
(Renamed_Object
(Entity
(N
)))
5724 return Is_Ref_To_Bit_Packed_Slice
(Renamed_Object
(Entity
(N
)));
5726 elsif Nkind
(N
) = N_Slice
5727 and then Is_Bit_Packed_Array
(Etype
(Prefix
(N
)))
5731 elsif Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
5732 return Is_Ref_To_Bit_Packed_Slice
(Prefix
(N
));
5737 end Is_Ref_To_Bit_Packed_Slice
;
5739 -----------------------
5740 -- Is_Renamed_Object --
5741 -----------------------
5743 function Is_Renamed_Object
(N
: Node_Id
) return Boolean is
5744 Pnod
: constant Node_Id
:= Parent
(N
);
5745 Kind
: constant Node_Kind
:= Nkind
(Pnod
);
5747 if Kind
= N_Object_Renaming_Declaration
then
5749 elsif Nkind_In
(Kind
, N_Indexed_Component
, N_Selected_Component
) then
5750 return Is_Renamed_Object
(Pnod
);
5754 end Is_Renamed_Object
;
5756 --------------------------------------
5757 -- Is_Secondary_Stack_BIP_Func_Call --
5758 --------------------------------------
5760 function Is_Secondary_Stack_BIP_Func_Call
(Expr
: Node_Id
) return Boolean is
5761 Alloc_Nam
: Name_Id
:= No_Name
;
5763 Call
: Node_Id
:= Expr
;
5768 -- Build-in-place calls usually appear in 'reference format. Note that
5769 -- the accessibility check machinery may add an extra 'reference due to
5770 -- side effect removal.
5772 while Nkind
(Call
) = N_Reference
loop
5773 Call
:= Prefix
(Call
);
5776 if Nkind_In
(Call
, N_Qualified_Expression
,
5777 N_Unchecked_Type_Conversion
)
5779 Call
:= Expression
(Call
);
5782 if Is_Build_In_Place_Function_Call
(Call
) then
5784 -- Examine all parameter associations of the function call
5786 Param
:= First
(Parameter_Associations
(Call
));
5787 while Present
(Param
) loop
5788 if Nkind
(Param
) = N_Parameter_Association
5789 and then Nkind
(Selector_Name
(Param
)) = N_Identifier
5791 Formal
:= Selector_Name
(Param
);
5792 Actual
:= Explicit_Actual_Parameter
(Param
);
5794 -- Construct the name of formal BIPalloc. It is much easier to
5795 -- extract the name of the function using an arbitrary formal's
5796 -- scope rather than the Name field of Call.
5798 if Alloc_Nam
= No_Name
and then Present
(Entity
(Formal
)) then
5801 (Chars
(Scope
(Entity
(Formal
))),
5802 BIP_Formal_Suffix
(BIP_Alloc_Form
));
5805 -- A match for BIPalloc => 2 has been found
5807 if Chars
(Formal
) = Alloc_Nam
5808 and then Nkind
(Actual
) = N_Integer_Literal
5809 and then Intval
(Actual
) = Uint_2
5820 end Is_Secondary_Stack_BIP_Func_Call
;
5822 -------------------------------------
5823 -- Is_Tag_To_Class_Wide_Conversion --
5824 -------------------------------------
5826 function Is_Tag_To_Class_Wide_Conversion
5827 (Obj_Id
: Entity_Id
) return Boolean
5829 Expr
: constant Node_Id
:= Expression
(Parent
(Obj_Id
));
5833 Is_Class_Wide_Type
(Etype
(Obj_Id
))
5834 and then Present
(Expr
)
5835 and then Nkind
(Expr
) = N_Unchecked_Type_Conversion
5836 and then Etype
(Expression
(Expr
)) = RTE
(RE_Tag
);
5837 end Is_Tag_To_Class_Wide_Conversion
;
5839 ----------------------------
5840 -- Is_Untagged_Derivation --
5841 ----------------------------
5843 function Is_Untagged_Derivation
(T
: Entity_Id
) return Boolean is
5845 return (not Is_Tagged_Type
(T
) and then Is_Derived_Type
(T
))
5847 (Is_Private_Type
(T
) and then Present
(Full_View
(T
))
5848 and then not Is_Tagged_Type
(Full_View
(T
))
5849 and then Is_Derived_Type
(Full_View
(T
))
5850 and then Etype
(Full_View
(T
)) /= T
);
5851 end Is_Untagged_Derivation
;
5853 ---------------------------
5854 -- Is_Volatile_Reference --
5855 ---------------------------
5857 function Is_Volatile_Reference
(N
: Node_Id
) return Boolean is
5859 -- Only source references are to be treated as volatile, internally
5860 -- generated stuff cannot have volatile external effects.
5862 if not Comes_From_Source
(N
) then
5865 -- Never true for reference to a type
5867 elsif Is_Entity_Name
(N
) and then Is_Type
(Entity
(N
)) then
5870 -- Never true for a compile time known constant
5872 elsif Compile_Time_Known_Value
(N
) then
5875 -- True if object reference with volatile type
5877 elsif Is_Volatile_Object
(N
) then
5880 -- True if reference to volatile entity
5882 elsif Is_Entity_Name
(N
) then
5883 return Treat_As_Volatile
(Entity
(N
));
5885 -- True for slice of volatile array
5887 elsif Nkind
(N
) = N_Slice
then
5888 return Is_Volatile_Reference
(Prefix
(N
));
5890 -- True if volatile component
5892 elsif Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
5893 if (Is_Entity_Name
(Prefix
(N
))
5894 and then Has_Volatile_Components
(Entity
(Prefix
(N
))))
5895 or else (Present
(Etype
(Prefix
(N
)))
5896 and then Has_Volatile_Components
(Etype
(Prefix
(N
))))
5900 return Is_Volatile_Reference
(Prefix
(N
));
5908 end Is_Volatile_Reference
;
5910 --------------------
5911 -- Kill_Dead_Code --
5912 --------------------
5914 procedure Kill_Dead_Code
(N
: Node_Id
; Warn
: Boolean := False) is
5915 W
: Boolean := Warn
;
5916 -- Set False if warnings suppressed
5920 Remove_Warning_Messages
(N
);
5922 -- Generate warning if appropriate
5926 -- We suppress the warning if this code is under control of an
5927 -- if statement, whose condition is a simple identifier, and
5928 -- either we are in an instance, or warnings off is set for this
5929 -- identifier. The reason for killing it in the instance case is
5930 -- that it is common and reasonable for code to be deleted in
5931 -- instances for various reasons.
5933 -- Could we use Is_Statically_Unevaluated here???
5935 if Nkind
(Parent
(N
)) = N_If_Statement
then
5937 C
: constant Node_Id
:= Condition
(Parent
(N
));
5939 if Nkind
(C
) = N_Identifier
5942 or else (Present
(Entity
(C
))
5943 and then Has_Warnings_Off
(Entity
(C
))))
5950 -- Generate warning if not suppressed
5954 ("?t?this code can never be executed and has been deleted!",
5959 -- Recurse into block statements and bodies to process declarations
5962 if Nkind
(N
) = N_Block_Statement
5963 or else Nkind
(N
) = N_Subprogram_Body
5964 or else Nkind
(N
) = N_Package_Body
5966 Kill_Dead_Code
(Declarations
(N
), False);
5967 Kill_Dead_Code
(Statements
(Handled_Statement_Sequence
(N
)));
5969 if Nkind
(N
) = N_Subprogram_Body
then
5970 Set_Is_Eliminated
(Defining_Entity
(N
));
5973 elsif Nkind
(N
) = N_Package_Declaration
then
5974 Kill_Dead_Code
(Visible_Declarations
(Specification
(N
)));
5975 Kill_Dead_Code
(Private_Declarations
(Specification
(N
)));
5977 -- ??? After this point, Delete_Tree has been called on all
5978 -- declarations in Specification (N), so references to entities
5979 -- therein look suspicious.
5982 E
: Entity_Id
:= First_Entity
(Defining_Entity
(N
));
5985 while Present
(E
) loop
5986 if Ekind
(E
) = E_Operator
then
5987 Set_Is_Eliminated
(E
);
5994 -- Recurse into composite statement to kill individual statements in
5995 -- particular instantiations.
5997 elsif Nkind
(N
) = N_If_Statement
then
5998 Kill_Dead_Code
(Then_Statements
(N
));
5999 Kill_Dead_Code
(Elsif_Parts
(N
));
6000 Kill_Dead_Code
(Else_Statements
(N
));
6002 elsif Nkind
(N
) = N_Loop_Statement
then
6003 Kill_Dead_Code
(Statements
(N
));
6005 elsif Nkind
(N
) = N_Case_Statement
then
6009 Alt
:= First
(Alternatives
(N
));
6010 while Present
(Alt
) loop
6011 Kill_Dead_Code
(Statements
(Alt
));
6016 elsif Nkind
(N
) = N_Case_Statement_Alternative
then
6017 Kill_Dead_Code
(Statements
(N
));
6019 -- Deal with dead instances caused by deleting instantiations
6021 elsif Nkind
(N
) in N_Generic_Instantiation
then
6022 Remove_Dead_Instance
(N
);
6027 -- Case where argument is a list of nodes to be killed
6029 procedure Kill_Dead_Code
(L
: List_Id
; Warn
: Boolean := False) is
6036 if Is_Non_Empty_List
(L
) then
6038 while Present
(N
) loop
6039 Kill_Dead_Code
(N
, W
);
6046 ------------------------
6047 -- Known_Non_Negative --
6048 ------------------------
6050 function Known_Non_Negative
(Opnd
: Node_Id
) return Boolean is
6052 if Is_OK_Static_Expression
(Opnd
) and then Expr_Value
(Opnd
) >= 0 then
6057 Lo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Opnd
));
6060 Is_OK_Static_Expression
(Lo
) and then Expr_Value
(Lo
) >= 0;
6063 end Known_Non_Negative
;
6065 --------------------
6066 -- Known_Non_Null --
6067 --------------------
6069 function Known_Non_Null
(N
: Node_Id
) return Boolean is
6071 -- Checks for case where N is an entity reference
6073 if Is_Entity_Name
(N
) and then Present
(Entity
(N
)) then
6075 E
: constant Entity_Id
:= Entity
(N
);
6080 -- First check if we are in decisive conditional
6082 Get_Current_Value_Condition
(N
, Op
, Val
);
6084 if Known_Null
(Val
) then
6085 if Op
= N_Op_Eq
then
6087 elsif Op
= N_Op_Ne
then
6092 -- If OK to do replacement, test Is_Known_Non_Null flag
6094 if OK_To_Do_Constant_Replacement
(E
) then
6095 return Is_Known_Non_Null
(E
);
6097 -- Otherwise if not safe to do replacement, then say so
6104 -- True if access attribute
6106 elsif Nkind
(N
) = N_Attribute_Reference
6107 and then Nam_In
(Attribute_Name
(N
), Name_Access
,
6108 Name_Unchecked_Access
,
6109 Name_Unrestricted_Access
)
6113 -- True if allocator
6115 elsif Nkind
(N
) = N_Allocator
then
6118 -- For a conversion, true if expression is known non-null
6120 elsif Nkind
(N
) = N_Type_Conversion
then
6121 return Known_Non_Null
(Expression
(N
));
6123 -- Above are all cases where the value could be determined to be
6124 -- non-null. In all other cases, we don't know, so return False.
6135 function Known_Null
(N
: Node_Id
) return Boolean is
6137 -- Checks for case where N is an entity reference
6139 if Is_Entity_Name
(N
) and then Present
(Entity
(N
)) then
6141 E
: constant Entity_Id
:= Entity
(N
);
6146 -- Constant null value is for sure null
6148 if Ekind
(E
) = E_Constant
6149 and then Known_Null
(Constant_Value
(E
))
6154 -- First check if we are in decisive conditional
6156 Get_Current_Value_Condition
(N
, Op
, Val
);
6158 if Known_Null
(Val
) then
6159 if Op
= N_Op_Eq
then
6161 elsif Op
= N_Op_Ne
then
6166 -- If OK to do replacement, test Is_Known_Null flag
6168 if OK_To_Do_Constant_Replacement
(E
) then
6169 return Is_Known_Null
(E
);
6171 -- Otherwise if not safe to do replacement, then say so
6178 -- True if explicit reference to null
6180 elsif Nkind
(N
) = N_Null
then
6183 -- For a conversion, true if expression is known null
6185 elsif Nkind
(N
) = N_Type_Conversion
then
6186 return Known_Null
(Expression
(N
));
6188 -- Above are all cases where the value could be determined to be null.
6189 -- In all other cases, we don't know, so return False.
6196 -----------------------------
6197 -- Make_CW_Equivalent_Type --
6198 -----------------------------
6200 -- Create a record type used as an equivalent of any member of the class
6201 -- which takes its size from exp.
6203 -- Generate the following code:
6205 -- type Equiv_T is record
6206 -- _parent : T (List of discriminant constraints taken from Exp);
6207 -- Ext__50 : Storage_Array (1 .. (Exp'size - Typ'object_size)/8);
6210 -- ??? Note that this type does not guarantee same alignment as all
6213 function Make_CW_Equivalent_Type
6215 E
: Node_Id
) return Entity_Id
6217 Loc
: constant Source_Ptr
:= Sloc
(E
);
6218 Root_Typ
: constant Entity_Id
:= Root_Type
(T
);
6219 List_Def
: constant List_Id
:= Empty_List
;
6220 Comp_List
: constant List_Id
:= New_List
;
6221 Equiv_Type
: Entity_Id
;
6222 Range_Type
: Entity_Id
;
6223 Str_Type
: Entity_Id
;
6224 Constr_Root
: Entity_Id
;
6228 -- If the root type is already constrained, there are no discriminants
6229 -- in the expression.
6231 if not Has_Discriminants
(Root_Typ
)
6232 or else Is_Constrained
(Root_Typ
)
6234 Constr_Root
:= Root_Typ
;
6236 -- At this point in the expansion, non-limited view of the type
6237 -- must be available, otherwise the error will be reported later.
6239 if From_Limited_With
(Constr_Root
)
6240 and then Present
(Non_Limited_View
(Constr_Root
))
6242 Constr_Root
:= Non_Limited_View
(Constr_Root
);
6246 Constr_Root
:= Make_Temporary
(Loc
, 'R');
6248 -- subtype cstr__n is T (List of discr constraints taken from Exp)
6250 Append_To
(List_Def
,
6251 Make_Subtype_Declaration
(Loc
,
6252 Defining_Identifier
=> Constr_Root
,
6253 Subtype_Indication
=> Make_Subtype_From_Expr
(E
, Root_Typ
)));
6256 -- Generate the range subtype declaration
6258 Range_Type
:= Make_Temporary
(Loc
, 'G');
6260 if not Is_Interface
(Root_Typ
) then
6262 -- subtype rg__xx is
6263 -- Storage_Offset range 1 .. (Expr'size - typ'size) / Storage_Unit
6266 Make_Op_Subtract
(Loc
,
6268 Make_Attribute_Reference
(Loc
,
6270 OK_Convert_To
(T
, Duplicate_Subexpr_No_Checks
(E
)),
6271 Attribute_Name
=> Name_Size
),
6273 Make_Attribute_Reference
(Loc
,
6274 Prefix
=> New_Occurrence_Of
(Constr_Root
, Loc
),
6275 Attribute_Name
=> Name_Object_Size
));
6277 -- subtype rg__xx is
6278 -- Storage_Offset range 1 .. Expr'size / Storage_Unit
6281 Make_Attribute_Reference
(Loc
,
6283 OK_Convert_To
(T
, Duplicate_Subexpr_No_Checks
(E
)),
6284 Attribute_Name
=> Name_Size
);
6287 Set_Paren_Count
(Sizexpr
, 1);
6289 Append_To
(List_Def
,
6290 Make_Subtype_Declaration
(Loc
,
6291 Defining_Identifier
=> Range_Type
,
6292 Subtype_Indication
=>
6293 Make_Subtype_Indication
(Loc
,
6294 Subtype_Mark
=> New_Occurrence_Of
(RTE
(RE_Storage_Offset
), Loc
),
6295 Constraint
=> Make_Range_Constraint
(Loc
,
6298 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
6300 Make_Op_Divide
(Loc
,
6301 Left_Opnd
=> Sizexpr
,
6302 Right_Opnd
=> Make_Integer_Literal
(Loc
,
6303 Intval
=> System_Storage_Unit
)))))));
6305 -- subtype str__nn is Storage_Array (rg__x);
6307 Str_Type
:= Make_Temporary
(Loc
, 'S');
6308 Append_To
(List_Def
,
6309 Make_Subtype_Declaration
(Loc
,
6310 Defining_Identifier
=> Str_Type
,
6311 Subtype_Indication
=>
6312 Make_Subtype_Indication
(Loc
,
6313 Subtype_Mark
=> New_Occurrence_Of
(RTE
(RE_Storage_Array
), Loc
),
6315 Make_Index_Or_Discriminant_Constraint
(Loc
,
6317 New_List
(New_Occurrence_Of
(Range_Type
, Loc
))))));
6319 -- type Equiv_T is record
6320 -- [ _parent : Tnn; ]
6324 Equiv_Type
:= Make_Temporary
(Loc
, 'T');
6325 Set_Ekind
(Equiv_Type
, E_Record_Type
);
6326 Set_Parent_Subtype
(Equiv_Type
, Constr_Root
);
6328 -- Set Is_Class_Wide_Equivalent_Type very early to trigger the special
6329 -- treatment for this type. In particular, even though _parent's type
6330 -- is a controlled type or contains controlled components, we do not
6331 -- want to set Has_Controlled_Component on it to avoid making it gain
6332 -- an unwanted _controller component.
6334 Set_Is_Class_Wide_Equivalent_Type
(Equiv_Type
);
6336 -- A class-wide equivalent type does not require initialization
6338 Set_Suppress_Initialization
(Equiv_Type
);
6340 if not Is_Interface
(Root_Typ
) then
6341 Append_To
(Comp_List
,
6342 Make_Component_Declaration
(Loc
,
6343 Defining_Identifier
=>
6344 Make_Defining_Identifier
(Loc
, Name_uParent
),
6345 Component_Definition
=>
6346 Make_Component_Definition
(Loc
,
6347 Aliased_Present
=> False,
6348 Subtype_Indication
=> New_Occurrence_Of
(Constr_Root
, Loc
))));
6351 Append_To
(Comp_List
,
6352 Make_Component_Declaration
(Loc
,
6353 Defining_Identifier
=> Make_Temporary
(Loc
, 'C'),
6354 Component_Definition
=>
6355 Make_Component_Definition
(Loc
,
6356 Aliased_Present
=> False,
6357 Subtype_Indication
=> New_Occurrence_Of
(Str_Type
, Loc
))));
6359 Append_To
(List_Def
,
6360 Make_Full_Type_Declaration
(Loc
,
6361 Defining_Identifier
=> Equiv_Type
,
6363 Make_Record_Definition
(Loc
,
6365 Make_Component_List
(Loc
,
6366 Component_Items
=> Comp_List
,
6367 Variant_Part
=> Empty
))));
6369 -- Suppress all checks during the analysis of the expanded code to avoid
6370 -- the generation of spurious warnings under ZFP run-time.
6372 Insert_Actions
(E
, List_Def
, Suppress
=> All_Checks
);
6374 end Make_CW_Equivalent_Type
;
6376 -------------------------
6377 -- Make_Invariant_Call --
6378 -------------------------
6380 function Make_Invariant_Call
(Expr
: Node_Id
) return Node_Id
is
6381 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
6385 Typ
:= Etype
(Expr
);
6387 -- Subtypes may be subject to invariants coming from their respective
6388 -- base types. The subtype may be fully or partially private.
6390 if Ekind_In
(Typ
, E_Array_Subtype
,
6393 E_Record_Subtype_With_Private
)
6395 Typ
:= Base_Type
(Typ
);
6399 (Has_Invariants
(Typ
) and then Present
(Invariant_Procedure
(Typ
)));
6402 Make_Procedure_Call_Statement
(Loc
,
6404 New_Occurrence_Of
(Invariant_Procedure
(Typ
), Loc
),
6405 Parameter_Associations
=> New_List
(Relocate_Node
(Expr
)));
6406 end Make_Invariant_Call
;
6408 ------------------------
6409 -- Make_Literal_Range --
6410 ------------------------
6412 function Make_Literal_Range
6414 Literal_Typ
: Entity_Id
) return Node_Id
6416 Lo
: constant Node_Id
:=
6417 New_Copy_Tree
(String_Literal_Low_Bound
(Literal_Typ
));
6418 Index
: constant Entity_Id
:= Etype
(Lo
);
6421 Length_Expr
: constant Node_Id
:=
6422 Make_Op_Subtract
(Loc
,
6424 Make_Integer_Literal
(Loc
,
6425 Intval
=> String_Literal_Length
(Literal_Typ
)),
6427 Make_Integer_Literal
(Loc
, 1));
6430 Set_Analyzed
(Lo
, False);
6432 if Is_Integer_Type
(Index
) then
6435 Left_Opnd
=> New_Copy_Tree
(Lo
),
6436 Right_Opnd
=> Length_Expr
);
6439 Make_Attribute_Reference
(Loc
,
6440 Attribute_Name
=> Name_Val
,
6441 Prefix
=> New_Occurrence_Of
(Index
, Loc
),
6442 Expressions
=> New_List
(
6445 Make_Attribute_Reference
(Loc
,
6446 Attribute_Name
=> Name_Pos
,
6447 Prefix
=> New_Occurrence_Of
(Index
, Loc
),
6448 Expressions
=> New_List
(New_Copy_Tree
(Lo
))),
6449 Right_Opnd
=> Length_Expr
)));
6456 end Make_Literal_Range
;
6458 --------------------------
6459 -- Make_Non_Empty_Check --
6460 --------------------------
6462 function Make_Non_Empty_Check
6464 N
: Node_Id
) return Node_Id
6470 Make_Attribute_Reference
(Loc
,
6471 Attribute_Name
=> Name_Length
,
6472 Prefix
=> Duplicate_Subexpr_No_Checks
(N
, Name_Req
=> True)),
6474 Make_Integer_Literal
(Loc
, 0));
6475 end Make_Non_Empty_Check
;
6477 -------------------------
6478 -- Make_Predicate_Call --
6479 -------------------------
6481 function Make_Predicate_Call
6484 Mem
: Boolean := False) return Node_Id
6486 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
6490 Save_Ghost_Mode
: constant Ghost_Mode_Type
:= Ghost_Mode
;
6493 pragma Assert
(Present
(Predicate_Function
(Typ
)));
6495 -- The related type may be subject to pragma Ghost. Set the mode now to
6496 -- ensure that the call is properly marked as Ghost.
6498 Set_Ghost_Mode_From_Entity
(Typ
);
6500 -- Call special membership version if requested and available
6503 PFM
:= Predicate_Function_M
(Typ
);
6505 if Present
(PFM
) then
6507 Make_Function_Call
(Loc
,
6508 Name
=> New_Occurrence_Of
(PFM
, Loc
),
6509 Parameter_Associations
=> New_List
(Relocate_Node
(Expr
)));
6511 Ghost_Mode
:= Save_Ghost_Mode
;
6516 -- Case of calling normal predicate function
6519 Make_Function_Call
(Loc
,
6521 New_Occurrence_Of
(Predicate_Function
(Typ
), Loc
),
6522 Parameter_Associations
=> New_List
(Relocate_Node
(Expr
)));
6524 Ghost_Mode
:= Save_Ghost_Mode
;
6526 end Make_Predicate_Call
;
6528 --------------------------
6529 -- Make_Predicate_Check --
6530 --------------------------
6532 function Make_Predicate_Check
6534 Expr
: Node_Id
) return Node_Id
6536 procedure Replace_Subtype_Reference
(N
: Node_Id
);
6537 -- Replace current occurrences of the subtype to which a dynamic
6538 -- predicate applies, by the expression that triggers a predicate
6539 -- check. This is needed for aspect Predicate_Failure, for which
6540 -- we do not generate a wrapper procedure, but simply modify the
6541 -- expression for the pragma of the predicate check.
6543 --------------------------------
6544 -- Replace_Subtype_Reference --
6545 --------------------------------
6547 procedure Replace_Subtype_Reference
(N
: Node_Id
) is
6549 Rewrite
(N
, New_Copy_Tree
(Expr
));
6551 -- We want to treat the node as if it comes from source, so
6552 -- that ASIS will not ignore it.
6554 Set_Comes_From_Source
(N
, True);
6555 end Replace_Subtype_Reference
;
6557 procedure Replace_Subtype_References
is
6558 new Replace_Type_References_Generic
(Replace_Subtype_Reference
);
6562 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
6564 Fail_Expr
: Node_Id
;
6567 -- Start of processing for Make_Predicate_Check
6570 -- If predicate checks are suppressed, then return a null statement. For
6571 -- this call, we check only the scope setting. If the caller wants to
6572 -- check a specific entity's setting, they must do it manually.
6574 if Predicate_Checks_Suppressed
(Empty
) then
6575 return Make_Null_Statement
(Loc
);
6578 -- Do not generate a check within an internal subprogram (stream
6579 -- functions and the like, including including predicate functions).
6581 if Within_Internal_Subprogram
then
6582 return Make_Null_Statement
(Loc
);
6585 -- Compute proper name to use, we need to get this right so that the
6586 -- right set of check policies apply to the Check pragma we are making.
6588 if Has_Dynamic_Predicate_Aspect
(Typ
) then
6589 Nam
:= Name_Dynamic_Predicate
;
6590 elsif Has_Static_Predicate_Aspect
(Typ
) then
6591 Nam
:= Name_Static_Predicate
;
6593 Nam
:= Name_Predicate
;
6596 Arg_List
:= New_List
(
6597 Make_Pragma_Argument_Association
(Loc
,
6598 Expression
=> Make_Identifier
(Loc
, Nam
)),
6599 Make_Pragma_Argument_Association
(Loc
,
6600 Expression
=> Make_Predicate_Call
(Typ
, Expr
)));
6602 -- If subtype has Predicate_Failure defined, add the correponding
6603 -- expression as an additional pragma parameter, after replacing
6604 -- current instances with the expression being checked.
6606 if Has_Aspect
(Typ
, Aspect_Predicate_Failure
) then
6609 (Expression
(Find_Aspect
(Typ
, Aspect_Predicate_Failure
)));
6610 Replace_Subtype_References
(Fail_Expr
, Typ
);
6612 Append_To
(Arg_List
,
6613 Make_Pragma_Argument_Association
(Loc
,
6614 Expression
=> Fail_Expr
));
6619 Pragma_Identifier
=> Make_Identifier
(Loc
, Name_Check
),
6620 Pragma_Argument_Associations
=> Arg_List
);
6621 end Make_Predicate_Check
;
6623 ----------------------------
6624 -- Make_Subtype_From_Expr --
6625 ----------------------------
6627 -- 1. If Expr is an unconstrained array expression, creates
6628 -- Unc_Type(Expr'first(1)..Expr'last(1),..., Expr'first(n)..Expr'last(n))
6630 -- 2. If Expr is a unconstrained discriminated type expression, creates
6631 -- Unc_Type(Expr.Discr1, ... , Expr.Discr_n)
6633 -- 3. If Expr is class-wide, creates an implicit class-wide subtype
6635 function Make_Subtype_From_Expr
6637 Unc_Typ
: Entity_Id
;
6638 Related_Id
: Entity_Id
:= Empty
) return Node_Id
6640 List_Constr
: constant List_Id
:= New_List
;
6641 Loc
: constant Source_Ptr
:= Sloc
(E
);
6644 Full_Subtyp
: Entity_Id
;
6645 High_Bound
: Entity_Id
;
6646 Index_Typ
: Entity_Id
;
6647 Low_Bound
: Entity_Id
;
6648 Priv_Subtyp
: Entity_Id
;
6652 if Is_Private_Type
(Unc_Typ
)
6653 and then Has_Unknown_Discriminants
(Unc_Typ
)
6655 -- The caller requests a unique external name for both the private
6656 -- and the full subtype.
6658 if Present
(Related_Id
) then
6660 Make_Defining_Identifier
(Loc
,
6661 Chars
=> New_External_Name
(Chars
(Related_Id
), 'C'));
6663 Make_Defining_Identifier
(Loc
,
6664 Chars
=> New_External_Name
(Chars
(Related_Id
), 'P'));
6667 Full_Subtyp
:= Make_Temporary
(Loc
, 'C');
6668 Priv_Subtyp
:= Make_Temporary
(Loc
, 'P');
6671 -- Prepare the subtype completion. Use the base type to find the
6672 -- underlying type because the type may be a generic actual or an
6673 -- explicit subtype.
6675 Utyp
:= Underlying_Type
(Base_Type
(Unc_Typ
));
6678 Unchecked_Convert_To
(Utyp
, Duplicate_Subexpr_No_Checks
(E
));
6679 Set_Parent
(Full_Exp
, Parent
(E
));
6682 Make_Subtype_Declaration
(Loc
,
6683 Defining_Identifier
=> Full_Subtyp
,
6684 Subtype_Indication
=> Make_Subtype_From_Expr
(Full_Exp
, Utyp
)));
6686 -- Define the dummy private subtype
6688 Set_Ekind
(Priv_Subtyp
, Subtype_Kind
(Ekind
(Unc_Typ
)));
6689 Set_Etype
(Priv_Subtyp
, Base_Type
(Unc_Typ
));
6690 Set_Scope
(Priv_Subtyp
, Full_Subtyp
);
6691 Set_Is_Constrained
(Priv_Subtyp
);
6692 Set_Is_Tagged_Type
(Priv_Subtyp
, Is_Tagged_Type
(Unc_Typ
));
6693 Set_Is_Itype
(Priv_Subtyp
);
6694 Set_Associated_Node_For_Itype
(Priv_Subtyp
, E
);
6696 if Is_Tagged_Type
(Priv_Subtyp
) then
6698 (Base_Type
(Priv_Subtyp
), Class_Wide_Type
(Unc_Typ
));
6699 Set_Direct_Primitive_Operations
(Priv_Subtyp
,
6700 Direct_Primitive_Operations
(Unc_Typ
));
6703 Set_Full_View
(Priv_Subtyp
, Full_Subtyp
);
6705 return New_Occurrence_Of
(Priv_Subtyp
, Loc
);
6707 elsif Is_Array_Type
(Unc_Typ
) then
6708 Index_Typ
:= First_Index
(Unc_Typ
);
6709 for J
in 1 .. Number_Dimensions
(Unc_Typ
) loop
6711 -- Capture the bounds of each index constraint in case the context
6712 -- is an object declaration of an unconstrained type initialized
6713 -- by a function call:
6715 -- Obj : Unconstr_Typ := Func_Call;
6717 -- This scenario requires secondary scope management and the index
6718 -- constraint cannot depend on the temporary used to capture the
6719 -- result of the function call.
6722 -- Temp : Unconstr_Typ_Ptr := Func_Call'reference;
6723 -- subtype S is Unconstr_Typ (Temp.all'First .. Temp.all'Last);
6724 -- Obj : S := Temp.all;
6725 -- SS_Release; -- Temp is gone at this point, bounds of S are
6729 -- Low_Bound : constant Base_Type (Index_Typ) := E'First (J);
6731 Low_Bound
:= Make_Temporary
(Loc
, 'B');
6733 Make_Object_Declaration
(Loc
,
6734 Defining_Identifier
=> Low_Bound
,
6735 Object_Definition
=>
6736 New_Occurrence_Of
(Base_Type
(Etype
(Index_Typ
)), Loc
),
6737 Constant_Present
=> True,
6739 Make_Attribute_Reference
(Loc
,
6740 Prefix
=> Duplicate_Subexpr_No_Checks
(E
),
6741 Attribute_Name
=> Name_First
,
6742 Expressions
=> New_List
(
6743 Make_Integer_Literal
(Loc
, J
)))));
6746 -- High_Bound : constant Base_Type (Index_Typ) := E'Last (J);
6748 High_Bound
:= Make_Temporary
(Loc
, 'B');
6750 Make_Object_Declaration
(Loc
,
6751 Defining_Identifier
=> High_Bound
,
6752 Object_Definition
=>
6753 New_Occurrence_Of
(Base_Type
(Etype
(Index_Typ
)), Loc
),
6754 Constant_Present
=> True,
6756 Make_Attribute_Reference
(Loc
,
6757 Prefix
=> Duplicate_Subexpr_No_Checks
(E
),
6758 Attribute_Name
=> Name_Last
,
6759 Expressions
=> New_List
(
6760 Make_Integer_Literal
(Loc
, J
)))));
6762 Append_To
(List_Constr
,
6764 Low_Bound
=> New_Occurrence_Of
(Low_Bound
, Loc
),
6765 High_Bound
=> New_Occurrence_Of
(High_Bound
, Loc
)));
6767 Index_Typ
:= Next_Index
(Index_Typ
);
6770 elsif Is_Class_Wide_Type
(Unc_Typ
) then
6772 CW_Subtype
: Entity_Id
;
6773 EQ_Typ
: Entity_Id
:= Empty
;
6776 -- A class-wide equivalent type is not needed on VM targets
6777 -- because the VM back-ends handle the class-wide object
6778 -- initialization itself (and doesn't need or want the
6779 -- additional intermediate type to handle the assignment).
6781 if Expander_Active
and then Tagged_Type_Expansion
then
6783 -- If this is the class-wide type of a completion that is a
6784 -- record subtype, set the type of the class-wide type to be
6785 -- the full base type, for use in the expanded code for the
6786 -- equivalent type. Should this be done earlier when the
6787 -- completion is analyzed ???
6789 if Is_Private_Type
(Etype
(Unc_Typ
))
6791 Ekind
(Full_View
(Etype
(Unc_Typ
))) = E_Record_Subtype
6793 Set_Etype
(Unc_Typ
, Base_Type
(Full_View
(Etype
(Unc_Typ
))));
6796 EQ_Typ
:= Make_CW_Equivalent_Type
(Unc_Typ
, E
);
6799 CW_Subtype
:= New_Class_Wide_Subtype
(Unc_Typ
, E
);
6800 Set_Equivalent_Type
(CW_Subtype
, EQ_Typ
);
6801 Set_Cloned_Subtype
(CW_Subtype
, Base_Type
(Unc_Typ
));
6803 return New_Occurrence_Of
(CW_Subtype
, Loc
);
6806 -- Indefinite record type with discriminants
6809 D
:= First_Discriminant
(Unc_Typ
);
6810 while Present
(D
) loop
6811 Append_To
(List_Constr
,
6812 Make_Selected_Component
(Loc
,
6813 Prefix
=> Duplicate_Subexpr_No_Checks
(E
),
6814 Selector_Name
=> New_Occurrence_Of
(D
, Loc
)));
6816 Next_Discriminant
(D
);
6821 Make_Subtype_Indication
(Loc
,
6822 Subtype_Mark
=> New_Occurrence_Of
(Unc_Typ
, Loc
),
6824 Make_Index_Or_Discriminant_Constraint
(Loc
,
6825 Constraints
=> List_Constr
));
6826 end Make_Subtype_From_Expr
;
6828 ----------------------------
6829 -- Matching_Standard_Type --
6830 ----------------------------
6832 function Matching_Standard_Type
(Typ
: Entity_Id
) return Entity_Id
is
6833 pragma Assert
(Is_Scalar_Type
(Typ
));
6834 Siz
: constant Uint
:= Esize
(Typ
);
6837 -- Floating-point cases
6839 if Is_Floating_Point_Type
(Typ
) then
6840 if Siz
<= Esize
(Standard_Short_Float
) then
6841 return Standard_Short_Float
;
6842 elsif Siz
<= Esize
(Standard_Float
) then
6843 return Standard_Float
;
6844 elsif Siz
<= Esize
(Standard_Long_Float
) then
6845 return Standard_Long_Float
;
6846 elsif Siz
<= Esize
(Standard_Long_Long_Float
) then
6847 return Standard_Long_Long_Float
;
6849 raise Program_Error
;
6852 -- Integer cases (includes fixed-point types)
6854 -- Unsigned integer cases (includes normal enumeration types)
6856 elsif Is_Unsigned_Type
(Typ
) then
6857 if Siz
<= Esize
(Standard_Short_Short_Unsigned
) then
6858 return Standard_Short_Short_Unsigned
;
6859 elsif Siz
<= Esize
(Standard_Short_Unsigned
) then
6860 return Standard_Short_Unsigned
;
6861 elsif Siz
<= Esize
(Standard_Unsigned
) then
6862 return Standard_Unsigned
;
6863 elsif Siz
<= Esize
(Standard_Long_Unsigned
) then
6864 return Standard_Long_Unsigned
;
6865 elsif Siz
<= Esize
(Standard_Long_Long_Unsigned
) then
6866 return Standard_Long_Long_Unsigned
;
6868 raise Program_Error
;
6871 -- Signed integer cases
6874 if Siz
<= Esize
(Standard_Short_Short_Integer
) then
6875 return Standard_Short_Short_Integer
;
6876 elsif Siz
<= Esize
(Standard_Short_Integer
) then
6877 return Standard_Short_Integer
;
6878 elsif Siz
<= Esize
(Standard_Integer
) then
6879 return Standard_Integer
;
6880 elsif Siz
<= Esize
(Standard_Long_Integer
) then
6881 return Standard_Long_Integer
;
6882 elsif Siz
<= Esize
(Standard_Long_Long_Integer
) then
6883 return Standard_Long_Long_Integer
;
6885 raise Program_Error
;
6888 end Matching_Standard_Type
;
6890 -----------------------------
6891 -- May_Generate_Large_Temp --
6892 -----------------------------
6894 -- At the current time, the only types that we return False for (i.e. where
6895 -- we decide we know they cannot generate large temps) are ones where we
6896 -- know the size is 256 bits or less at compile time, and we are still not
6897 -- doing a thorough job on arrays and records ???
6899 function May_Generate_Large_Temp
(Typ
: Entity_Id
) return Boolean is
6901 if not Size_Known_At_Compile_Time
(Typ
) then
6904 elsif Esize
(Typ
) /= 0 and then Esize
(Typ
) <= 256 then
6907 elsif Is_Array_Type
(Typ
)
6908 and then Present
(Packed_Array_Impl_Type
(Typ
))
6910 return May_Generate_Large_Temp
(Packed_Array_Impl_Type
(Typ
));
6912 -- We could do more here to find other small types ???
6917 end May_Generate_Large_Temp
;
6919 ------------------------
6920 -- Needs_Finalization --
6921 ------------------------
6923 function Needs_Finalization
(T
: Entity_Id
) return Boolean is
6924 function Has_Some_Controlled_Component
(Rec
: Entity_Id
) return Boolean;
6925 -- If type is not frozen yet, check explicitly among its components,
6926 -- because the Has_Controlled_Component flag is not necessarily set.
6928 -----------------------------------
6929 -- Has_Some_Controlled_Component --
6930 -----------------------------------
6932 function Has_Some_Controlled_Component
6933 (Rec
: Entity_Id
) return Boolean
6938 if Has_Controlled_Component
(Rec
) then
6941 elsif not Is_Frozen
(Rec
) then
6942 if Is_Record_Type
(Rec
) then
6943 Comp
:= First_Entity
(Rec
);
6945 while Present
(Comp
) loop
6946 if not Is_Type
(Comp
)
6947 and then Needs_Finalization
(Etype
(Comp
))
6960 and then Needs_Finalization
(Component_Type
(Rec
));
6965 end Has_Some_Controlled_Component
;
6967 -- Start of processing for Needs_Finalization
6970 -- Certain run-time configurations and targets do not provide support
6971 -- for controlled types.
6973 if Restriction_Active
(No_Finalization
) then
6976 -- C++ types are not considered controlled. It is assumed that the
6977 -- non-Ada side will handle their clean up.
6979 elsif Convention
(T
) = Convention_CPP
then
6982 -- Never needs finalization if Disable_Controlled set
6984 elsif Disable_Controlled
(T
) then
6987 elsif Is_Class_Wide_Type
(T
) and then Disable_Controlled
(Etype
(T
)) then
6991 -- Class-wide types are treated as controlled because derivations
6992 -- from the root type can introduce controlled components.
6994 return Is_Class_Wide_Type
(T
)
6995 or else Is_Controlled
(T
)
6996 or else Has_Some_Controlled_Component
(T
)
6998 (Is_Concurrent_Type
(T
)
6999 and then Present
(Corresponding_Record_Type
(T
))
7000 and then Needs_Finalization
(Corresponding_Record_Type
(T
)));
7002 end Needs_Finalization
;
7004 ----------------------------
7005 -- Needs_Constant_Address --
7006 ----------------------------
7008 function Needs_Constant_Address
7010 Typ
: Entity_Id
) return Boolean
7014 -- If we have no initialization of any kind, then we don't need to place
7015 -- any restrictions on the address clause, because the object will be
7016 -- elaborated after the address clause is evaluated. This happens if the
7017 -- declaration has no initial expression, or the type has no implicit
7018 -- initialization, or the object is imported.
7020 -- The same holds for all initialized scalar types and all access types.
7021 -- Packed bit arrays of size up to 64 are represented using a modular
7022 -- type with an initialization (to zero) and can be processed like other
7023 -- initialized scalar types.
7025 -- If the type is controlled, code to attach the object to a
7026 -- finalization chain is generated at the point of declaration, and
7027 -- therefore the elaboration of the object cannot be delayed: the
7028 -- address expression must be a constant.
7030 if No
(Expression
(Decl
))
7031 and then not Needs_Finalization
(Typ
)
7033 (not Has_Non_Null_Base_Init_Proc
(Typ
)
7034 or else Is_Imported
(Defining_Identifier
(Decl
)))
7038 elsif (Present
(Expression
(Decl
)) and then Is_Scalar_Type
(Typ
))
7039 or else Is_Access_Type
(Typ
)
7041 (Is_Bit_Packed_Array
(Typ
)
7042 and then Is_Modular_Integer_Type
(Packed_Array_Impl_Type
(Typ
)))
7048 -- Otherwise, we require the address clause to be constant because
7049 -- the call to the initialization procedure (or the attach code) has
7050 -- to happen at the point of the declaration.
7052 -- Actually the IP call has been moved to the freeze actions anyway,
7053 -- so maybe we can relax this restriction???
7057 end Needs_Constant_Address
;
7059 ----------------------------
7060 -- New_Class_Wide_Subtype --
7061 ----------------------------
7063 function New_Class_Wide_Subtype
7064 (CW_Typ
: Entity_Id
;
7065 N
: Node_Id
) return Entity_Id
7067 Res
: constant Entity_Id
:= Create_Itype
(E_Void
, N
);
7068 Res_Name
: constant Name_Id
:= Chars
(Res
);
7069 Res_Scope
: constant Entity_Id
:= Scope
(Res
);
7072 Copy_Node
(CW_Typ
, Res
);
7073 Set_Comes_From_Source
(Res
, False);
7074 Set_Sloc
(Res
, Sloc
(N
));
7076 Set_Associated_Node_For_Itype
(Res
, N
);
7077 Set_Is_Public
(Res
, False); -- By default, may be changed below.
7078 Set_Public_Status
(Res
);
7079 Set_Chars
(Res
, Res_Name
);
7080 Set_Scope
(Res
, Res_Scope
);
7081 Set_Ekind
(Res
, E_Class_Wide_Subtype
);
7082 Set_Next_Entity
(Res
, Empty
);
7083 Set_Etype
(Res
, Base_Type
(CW_Typ
));
7084 Set_Is_Frozen
(Res
, False);
7085 Set_Freeze_Node
(Res
, Empty
);
7087 end New_Class_Wide_Subtype
;
7089 --------------------------------
7090 -- Non_Limited_Designated_Type --
7091 ---------------------------------
7093 function Non_Limited_Designated_Type
(T
: Entity_Id
) return Entity_Id
is
7094 Desig
: constant Entity_Id
:= Designated_Type
(T
);
7096 if Has_Non_Limited_View
(Desig
) then
7097 return Non_Limited_View
(Desig
);
7101 end Non_Limited_Designated_Type
;
7103 -----------------------------------
7104 -- OK_To_Do_Constant_Replacement --
7105 -----------------------------------
7107 function OK_To_Do_Constant_Replacement
(E
: Entity_Id
) return Boolean is
7108 ES
: constant Entity_Id
:= Scope
(E
);
7112 -- Do not replace statically allocated objects, because they may be
7113 -- modified outside the current scope.
7115 if Is_Statically_Allocated
(E
) then
7118 -- Do not replace aliased or volatile objects, since we don't know what
7119 -- else might change the value.
7121 elsif Is_Aliased
(E
) or else Treat_As_Volatile
(E
) then
7124 -- Debug flag -gnatdM disconnects this optimization
7126 elsif Debug_Flag_MM
then
7129 -- Otherwise check scopes
7132 CS
:= Current_Scope
;
7135 -- If we are in right scope, replacement is safe
7140 -- Packages do not affect the determination of safety
7142 elsif Ekind
(CS
) = E_Package
then
7143 exit when CS
= Standard_Standard
;
7146 -- Blocks do not affect the determination of safety
7148 elsif Ekind
(CS
) = E_Block
then
7151 -- Loops do not affect the determination of safety. Note that we
7152 -- kill all current values on entry to a loop, so we are just
7153 -- talking about processing within a loop here.
7155 elsif Ekind
(CS
) = E_Loop
then
7158 -- Otherwise, the reference is dubious, and we cannot be sure that
7159 -- it is safe to do the replacement.
7168 end OK_To_Do_Constant_Replacement
;
7170 ------------------------------------
7171 -- Possible_Bit_Aligned_Component --
7172 ------------------------------------
7174 function Possible_Bit_Aligned_Component
(N
: Node_Id
) return Boolean is
7176 -- Do not process an unanalyzed node because it is not yet decorated and
7177 -- most checks performed below will fail.
7179 if not Analyzed
(N
) then
7185 -- Case of indexed component
7187 when N_Indexed_Component
=>
7189 P
: constant Node_Id
:= Prefix
(N
);
7190 Ptyp
: constant Entity_Id
:= Etype
(P
);
7193 -- If we know the component size and it is less than 64, then
7194 -- we are definitely OK. The back end always does assignment of
7195 -- misaligned small objects correctly.
7197 if Known_Static_Component_Size
(Ptyp
)
7198 and then Component_Size
(Ptyp
) <= 64
7202 -- Otherwise, we need to test the prefix, to see if we are
7203 -- indexing from a possibly unaligned component.
7206 return Possible_Bit_Aligned_Component
(P
);
7210 -- Case of selected component
7212 when N_Selected_Component
=>
7214 P
: constant Node_Id
:= Prefix
(N
);
7215 Comp
: constant Entity_Id
:= Entity
(Selector_Name
(N
));
7218 -- If there is no component clause, then we are in the clear
7219 -- since the back end will never misalign a large component
7220 -- unless it is forced to do so. In the clear means we need
7221 -- only the recursive test on the prefix.
7223 if Component_May_Be_Bit_Aligned
(Comp
) then
7226 return Possible_Bit_Aligned_Component
(P
);
7230 -- For a slice, test the prefix, if that is possibly misaligned,
7231 -- then for sure the slice is.
7234 return Possible_Bit_Aligned_Component
(Prefix
(N
));
7236 -- For an unchecked conversion, check whether the expression may
7239 when N_Unchecked_Type_Conversion
=>
7240 return Possible_Bit_Aligned_Component
(Expression
(N
));
7242 -- If we have none of the above, it means that we have fallen off the
7243 -- top testing prefixes recursively, and we now have a stand alone
7244 -- object, where we don't have a problem, unless this is a renaming,
7245 -- in which case we need to look into the renamed object.
7248 if Is_Entity_Name
(N
)
7249 and then Present
(Renamed_Object
(Entity
(N
)))
7252 Possible_Bit_Aligned_Component
(Renamed_Object
(Entity
(N
)));
7258 end Possible_Bit_Aligned_Component
;
7260 -----------------------------------------------
7261 -- Process_Statements_For_Controlled_Objects --
7262 -----------------------------------------------
7264 procedure Process_Statements_For_Controlled_Objects
(N
: Node_Id
) is
7265 Loc
: constant Source_Ptr
:= Sloc
(N
);
7267 function Are_Wrapped
(L
: List_Id
) return Boolean;
7268 -- Determine whether list L contains only one statement which is a block
7270 function Wrap_Statements_In_Block
7272 Scop
: Entity_Id
:= Current_Scope
) return Node_Id
;
7273 -- Given a list of statements L, wrap it in a block statement and return
7274 -- the generated node. Scop is either the current scope or the scope of
7275 -- the context (if applicable).
7281 function Are_Wrapped
(L
: List_Id
) return Boolean is
7282 Stmt
: constant Node_Id
:= First
(L
);
7286 and then No
(Next
(Stmt
))
7287 and then Nkind
(Stmt
) = N_Block_Statement
;
7290 ------------------------------
7291 -- Wrap_Statements_In_Block --
7292 ------------------------------
7294 function Wrap_Statements_In_Block
7296 Scop
: Entity_Id
:= Current_Scope
) return Node_Id
7298 Block_Id
: Entity_Id
;
7299 Block_Nod
: Node_Id
;
7300 Iter_Loop
: Entity_Id
;
7304 Make_Block_Statement
(Loc
,
7305 Declarations
=> No_List
,
7306 Handled_Statement_Sequence
=>
7307 Make_Handled_Sequence_Of_Statements
(Loc
,
7310 -- Create a label for the block in case the block needs to manage the
7311 -- secondary stack. A label allows for flag Uses_Sec_Stack to be set.
7313 Add_Block_Identifier
(Block_Nod
, Block_Id
);
7315 -- When wrapping the statements of an iterator loop, check whether
7316 -- the loop requires secondary stack management and if so, propagate
7317 -- the appropriate flags to the block. This ensures that the cursor
7318 -- is properly cleaned up at each iteration of the loop.
7320 Iter_Loop
:= Find_Enclosing_Iterator_Loop
(Scop
);
7322 if Present
(Iter_Loop
) then
7323 Set_Uses_Sec_Stack
(Block_Id
, Uses_Sec_Stack
(Iter_Loop
));
7325 -- Secondary stack reclamation is suppressed when the associated
7326 -- iterator loop contains a return statement which uses the stack.
7328 Set_Sec_Stack_Needed_For_Return
7329 (Block_Id
, Sec_Stack_Needed_For_Return
(Iter_Loop
));
7333 end Wrap_Statements_In_Block
;
7339 -- Start of processing for Process_Statements_For_Controlled_Objects
7342 -- Whenever a non-handled statement list is wrapped in a block, the
7343 -- block must be explicitly analyzed to redecorate all entities in the
7344 -- list and ensure that a finalizer is properly built.
7349 N_Conditional_Entry_Call |
7350 N_Selective_Accept
=>
7352 -- Check the "then statements" for elsif parts and if statements
7354 if Nkind_In
(N
, N_Elsif_Part
, N_If_Statement
)
7355 and then not Is_Empty_List
(Then_Statements
(N
))
7356 and then not Are_Wrapped
(Then_Statements
(N
))
7357 and then Requires_Cleanup_Actions
7358 (Then_Statements
(N
), False, False)
7360 Block
:= Wrap_Statements_In_Block
(Then_Statements
(N
));
7361 Set_Then_Statements
(N
, New_List
(Block
));
7366 -- Check the "else statements" for conditional entry calls, if
7367 -- statements and selective accepts.
7369 if Nkind_In
(N
, N_Conditional_Entry_Call
,
7372 and then not Is_Empty_List
(Else_Statements
(N
))
7373 and then not Are_Wrapped
(Else_Statements
(N
))
7374 and then Requires_Cleanup_Actions
7375 (Else_Statements
(N
), False, False)
7377 Block
:= Wrap_Statements_In_Block
(Else_Statements
(N
));
7378 Set_Else_Statements
(N
, New_List
(Block
));
7383 when N_Abortable_Part |
7384 N_Accept_Alternative |
7385 N_Case_Statement_Alternative |
7386 N_Delay_Alternative |
7387 N_Entry_Call_Alternative |
7388 N_Exception_Handler |
7390 N_Triggering_Alternative
=>
7392 if not Is_Empty_List
(Statements
(N
))
7393 and then not Are_Wrapped
(Statements
(N
))
7394 and then Requires_Cleanup_Actions
(Statements
(N
), False, False)
7396 if Nkind
(N
) = N_Loop_Statement
7397 and then Present
(Identifier
(N
))
7400 Wrap_Statements_In_Block
7401 (L
=> Statements
(N
),
7402 Scop
=> Entity
(Identifier
(N
)));
7404 Block
:= Wrap_Statements_In_Block
(Statements
(N
));
7407 Set_Statements
(N
, New_List
(Block
));
7414 end Process_Statements_For_Controlled_Objects
;
7420 function Power_Of_Two
(N
: Node_Id
) return Nat
is
7421 Typ
: constant Entity_Id
:= Etype
(N
);
7422 pragma Assert
(Is_Integer_Type
(Typ
));
7424 Siz
: constant Nat
:= UI_To_Int
(Esize
(Typ
));
7428 if not Compile_Time_Known_Value
(N
) then
7432 Val
:= Expr_Value
(N
);
7433 for J
in 1 .. Siz
- 1 loop
7434 if Val
= Uint_2
** J
then
7443 ----------------------
7444 -- Remove_Init_Call --
7445 ----------------------
7447 function Remove_Init_Call
7449 Rep_Clause
: Node_Id
) return Node_Id
7451 Par
: constant Node_Id
:= Parent
(Var
);
7452 Typ
: constant Entity_Id
:= Etype
(Var
);
7454 Init_Proc
: Entity_Id
;
7455 -- Initialization procedure for Typ
7457 function Find_Init_Call_In_List
(From
: Node_Id
) return Node_Id
;
7458 -- Look for init call for Var starting at From and scanning the
7459 -- enclosing list until Rep_Clause or the end of the list is reached.
7461 ----------------------------
7462 -- Find_Init_Call_In_List --
7463 ----------------------------
7465 function Find_Init_Call_In_List
(From
: Node_Id
) return Node_Id
is
7466 Init_Call
: Node_Id
;
7470 while Present
(Init_Call
) and then Init_Call
/= Rep_Clause
loop
7471 if Nkind
(Init_Call
) = N_Procedure_Call_Statement
7472 and then Is_Entity_Name
(Name
(Init_Call
))
7473 and then Entity
(Name
(Init_Call
)) = Init_Proc
7482 end Find_Init_Call_In_List
;
7484 Init_Call
: Node_Id
;
7486 -- Start of processing for Find_Init_Call
7489 if Present
(Initialization_Statements
(Var
)) then
7490 Init_Call
:= Initialization_Statements
(Var
);
7491 Set_Initialization_Statements
(Var
, Empty
);
7493 elsif not Has_Non_Null_Base_Init_Proc
(Typ
) then
7495 -- No init proc for the type, so obviously no call to be found
7500 -- We might be able to handle other cases below by just properly
7501 -- setting Initialization_Statements at the point where the init proc
7502 -- call is generated???
7504 Init_Proc
:= Base_Init_Proc
(Typ
);
7506 -- First scan the list containing the declaration of Var
7508 Init_Call
:= Find_Init_Call_In_List
(From
=> Next
(Par
));
7510 -- If not found, also look on Var's freeze actions list, if any,
7511 -- since the init call may have been moved there (case of an address
7512 -- clause applying to Var).
7514 if No
(Init_Call
) and then Present
(Freeze_Node
(Var
)) then
7516 Find_Init_Call_In_List
(First
(Actions
(Freeze_Node
(Var
))));
7519 -- If the initialization call has actuals that use the secondary
7520 -- stack, the call may have been wrapped into a temporary block, in
7521 -- which case the block itself has to be removed.
7523 if No
(Init_Call
) and then Nkind
(Next
(Par
)) = N_Block_Statement
then
7525 Blk
: constant Node_Id
:= Next
(Par
);
7528 (Find_Init_Call_In_List
7529 (First
(Statements
(Handled_Statement_Sequence
(Blk
)))))
7537 if Present
(Init_Call
) then
7541 end Remove_Init_Call
;
7543 -------------------------
7544 -- Remove_Side_Effects --
7545 -------------------------
7547 procedure Remove_Side_Effects
7549 Name_Req
: Boolean := False;
7550 Renaming_Req
: Boolean := False;
7551 Variable_Ref
: Boolean := False;
7552 Related_Id
: Entity_Id
:= Empty
;
7553 Is_Low_Bound
: Boolean := False;
7554 Is_High_Bound
: Boolean := False)
7556 function Build_Temporary
7559 Related_Nod
: Node_Id
:= Empty
) return Entity_Id
;
7560 -- Create an external symbol of the form xxx_FIRST/_LAST if Related_Nod
7561 -- is present (xxx is taken from the Chars field of Related_Nod),
7562 -- otherwise it generates an internal temporary.
7564 function Is_Name_Reference
(N
: Node_Id
) return Boolean;
7565 -- Determine if the tree referenced by N represents a name. This is
7566 -- similar to Is_Object_Reference but returns true only if N can be
7567 -- renamed without the need for a temporary, the typical example of
7568 -- an object not in this category being a function call.
7570 ---------------------
7571 -- Build_Temporary --
7572 ---------------------
7574 function Build_Temporary
7577 Related_Nod
: Node_Id
:= Empty
) return Entity_Id
7582 -- The context requires an external symbol
7584 if Present
(Related_Id
) then
7585 if Is_Low_Bound
then
7586 Temp_Nam
:= New_External_Name
(Chars
(Related_Id
), "_FIRST");
7587 else pragma Assert
(Is_High_Bound
);
7588 Temp_Nam
:= New_External_Name
(Chars
(Related_Id
), "_LAST");
7591 return Make_Defining_Identifier
(Loc
, Temp_Nam
);
7593 -- Otherwise generate an internal temporary
7596 return Make_Temporary
(Loc
, Id
, Related_Nod
);
7598 end Build_Temporary
;
7600 -----------------------
7601 -- Is_Name_Reference --
7602 -----------------------
7604 function Is_Name_Reference
(N
: Node_Id
) return Boolean is
7606 if Is_Entity_Name
(N
) then
7607 return Present
(Entity
(N
)) and then Is_Object
(Entity
(N
));
7611 when N_Indexed_Component | N_Slice
=>
7613 Is_Name_Reference
(Prefix
(N
))
7614 or else Is_Access_Type
(Etype
(Prefix
(N
)));
7616 -- Attributes 'Input, 'Old and 'Result produce objects
7618 when N_Attribute_Reference
=>
7621 (Attribute_Name
(N
), Name_Input
, Name_Old
, Name_Result
);
7623 when N_Selected_Component
=>
7625 Is_Name_Reference
(Selector_Name
(N
))
7627 (Is_Name_Reference
(Prefix
(N
))
7628 or else Is_Access_Type
(Etype
(Prefix
(N
))));
7630 when N_Explicit_Dereference
=>
7633 -- A view conversion of a tagged name is a name reference
7635 when N_Type_Conversion
=>
7636 return Is_Tagged_Type
(Etype
(Subtype_Mark
(N
)))
7637 and then Is_Tagged_Type
(Etype
(Expression
(N
)))
7638 and then Is_Name_Reference
(Expression
(N
));
7640 -- An unchecked type conversion is considered to be a name if
7641 -- the operand is a name (this construction arises only as a
7642 -- result of expansion activities).
7644 when N_Unchecked_Type_Conversion
=>
7645 return Is_Name_Reference
(Expression
(N
));
7650 end Is_Name_Reference
;
7654 Loc
: constant Source_Ptr
:= Sloc
(Exp
);
7655 Exp_Type
: constant Entity_Id
:= Etype
(Exp
);
7656 Svg_Suppress
: constant Suppress_Record
:= Scope_Suppress
;
7660 Ptr_Typ_Decl
: Node_Id
;
7661 Ref_Type
: Entity_Id
;
7664 -- Start of processing for Remove_Side_Effects
7667 -- Handle cases in which there is nothing to do. In GNATprove mode,
7668 -- removal of side effects is useful for the light expansion of
7669 -- renamings. This removal should only occur when not inside a
7670 -- generic and not doing a pre-analysis.
7672 if not Expander_Active
7673 and (Inside_A_Generic
or not Full_Analysis
or not GNATprove_Mode
)
7678 -- Cannot generate temporaries if the invocation to remove side effects
7679 -- was issued too early and the type of the expression is not resolved
7680 -- (this happens because routines Duplicate_Subexpr_XX implicitly invoke
7681 -- Remove_Side_Effects).
7683 if No
(Exp_Type
) or else Ekind
(Exp_Type
) = E_Access_Attribute_Type
then
7686 -- No action needed for side-effect free expressions
7688 elsif Side_Effect_Free
(Exp
, Name_Req
, Variable_Ref
) then
7692 -- The remaining processing is done with all checks suppressed
7694 -- Note: from now on, don't use return statements, instead do a goto
7695 -- Leave, to ensure that we properly restore Scope_Suppress.Suppress.
7697 Scope_Suppress
.Suppress
:= (others => True);
7699 -- If it is an elementary type and we need to capture the value, just
7700 -- make a constant. Likewise if this is not a name reference, except
7701 -- for a type conversion because we would enter an infinite recursion
7702 -- with Checks.Apply_Predicate_Check if the target type has predicates.
7703 -- And type conversions need a specific treatment anyway, see below.
7704 -- Also do it if we have a volatile reference and Name_Req is not set
7705 -- (see comments for Side_Effect_Free).
7707 if Is_Elementary_Type
(Exp_Type
)
7708 and then (Variable_Ref
7709 or else (not Is_Name_Reference
(Exp
)
7710 and then Nkind
(Exp
) /= N_Type_Conversion
)
7711 or else (not Name_Req
7712 and then Is_Volatile_Reference
(Exp
)))
7714 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7715 Set_Etype
(Def_Id
, Exp_Type
);
7716 Res
:= New_Occurrence_Of
(Def_Id
, Loc
);
7718 -- If the expression is a packed reference, it must be reanalyzed and
7719 -- expanded, depending on context. This is the case for actuals where
7720 -- a constraint check may capture the actual before expansion of the
7721 -- call is complete.
7723 if Nkind
(Exp
) = N_Indexed_Component
7724 and then Is_Packed
(Etype
(Prefix
(Exp
)))
7726 Set_Analyzed
(Exp
, False);
7727 Set_Analyzed
(Prefix
(Exp
), False);
7731 -- Rnn : Exp_Type renames Expr;
7733 if Renaming_Req
then
7735 Make_Object_Renaming_Declaration
(Loc
,
7736 Defining_Identifier
=> Def_Id
,
7737 Subtype_Mark
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7738 Name
=> Relocate_Node
(Exp
));
7741 -- Rnn : constant Exp_Type := Expr;
7745 Make_Object_Declaration
(Loc
,
7746 Defining_Identifier
=> Def_Id
,
7747 Object_Definition
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7748 Constant_Present
=> True,
7749 Expression
=> Relocate_Node
(Exp
));
7751 Set_Assignment_OK
(E
);
7754 Insert_Action
(Exp
, E
);
7756 -- If the expression has the form v.all then we can just capture the
7757 -- pointer, and then do an explicit dereference on the result, but
7758 -- this is not right if this is a volatile reference.
7760 elsif Nkind
(Exp
) = N_Explicit_Dereference
7761 and then not Is_Volatile_Reference
(Exp
)
7763 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7765 Make_Explicit_Dereference
(Loc
, New_Occurrence_Of
(Def_Id
, Loc
));
7768 Make_Object_Declaration
(Loc
,
7769 Defining_Identifier
=> Def_Id
,
7770 Object_Definition
=>
7771 New_Occurrence_Of
(Etype
(Prefix
(Exp
)), Loc
),
7772 Constant_Present
=> True,
7773 Expression
=> Relocate_Node
(Prefix
(Exp
))));
7775 -- Similar processing for an unchecked conversion of an expression of
7776 -- the form v.all, where we want the same kind of treatment.
7778 elsif Nkind
(Exp
) = N_Unchecked_Type_Conversion
7779 and then Nkind
(Expression
(Exp
)) = N_Explicit_Dereference
7781 Remove_Side_Effects
(Expression
(Exp
), Name_Req
, Variable_Ref
);
7784 -- If this is a type conversion, leave the type conversion and remove
7785 -- the side effects in the expression. This is important in several
7786 -- circumstances: for change of representations, and also when this is a
7787 -- view conversion to a smaller object, where gigi can end up creating
7788 -- its own temporary of the wrong size.
7790 elsif Nkind
(Exp
) = N_Type_Conversion
then
7791 Remove_Side_Effects
(Expression
(Exp
), Name_Req
, Variable_Ref
);
7793 -- Generating C code the type conversion of an access to constrained
7794 -- array type into an access to unconstrained array type involves
7795 -- initializing a fat pointer and the expression must be free of
7796 -- side effects to safely compute its bounds.
7799 and then Is_Access_Type
(Etype
(Exp
))
7800 and then Is_Array_Type
(Designated_Type
(Etype
(Exp
)))
7801 and then not Is_Constrained
(Designated_Type
(Etype
(Exp
)))
7803 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7804 Set_Etype
(Def_Id
, Exp_Type
);
7805 Res
:= New_Occurrence_Of
(Def_Id
, Loc
);
7808 Make_Object_Declaration
(Loc
,
7809 Defining_Identifier
=> Def_Id
,
7810 Object_Definition
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7811 Constant_Present
=> True,
7812 Expression
=> Relocate_Node
(Exp
)));
7817 -- If this is an unchecked conversion that Gigi can't handle, make
7818 -- a copy or a use a renaming to capture the value.
7820 elsif Nkind
(Exp
) = N_Unchecked_Type_Conversion
7821 and then not Safe_Unchecked_Type_Conversion
(Exp
)
7823 if CW_Or_Has_Controlled_Part
(Exp_Type
) then
7825 -- Use a renaming to capture the expression, rather than create
7826 -- a controlled temporary.
7828 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7829 Res
:= New_Occurrence_Of
(Def_Id
, Loc
);
7832 Make_Object_Renaming_Declaration
(Loc
,
7833 Defining_Identifier
=> Def_Id
,
7834 Subtype_Mark
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7835 Name
=> Relocate_Node
(Exp
)));
7838 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7839 Set_Etype
(Def_Id
, Exp_Type
);
7840 Res
:= New_Occurrence_Of
(Def_Id
, Loc
);
7843 Make_Object_Declaration
(Loc
,
7844 Defining_Identifier
=> Def_Id
,
7845 Object_Definition
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7846 Constant_Present
=> not Is_Variable
(Exp
),
7847 Expression
=> Relocate_Node
(Exp
));
7849 Set_Assignment_OK
(E
);
7850 Insert_Action
(Exp
, E
);
7853 -- For expressions that denote names, we can use a renaming scheme.
7854 -- This is needed for correctness in the case of a volatile object of
7855 -- a non-volatile type because the Make_Reference call of the "default"
7856 -- approach would generate an illegal access value (an access value
7857 -- cannot designate such an object - see Analyze_Reference).
7859 elsif Is_Name_Reference
(Exp
)
7861 -- We skip using this scheme if we have an object of a volatile
7862 -- type and we do not have Name_Req set true (see comments for
7863 -- Side_Effect_Free).
7865 and then (Name_Req
or else not Treat_As_Volatile
(Exp_Type
))
7867 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7868 Res
:= New_Occurrence_Of
(Def_Id
, Loc
);
7871 Make_Object_Renaming_Declaration
(Loc
,
7872 Defining_Identifier
=> Def_Id
,
7873 Subtype_Mark
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7874 Name
=> Relocate_Node
(Exp
)));
7876 -- If this is a packed reference, or a selected component with
7877 -- a non-standard representation, a reference to the temporary
7878 -- will be replaced by a copy of the original expression (see
7879 -- Exp_Ch2.Expand_Renaming). Otherwise the temporary must be
7880 -- elaborated by gigi, and is of course not to be replaced in-line
7881 -- by the expression it renames, which would defeat the purpose of
7882 -- removing the side-effect.
7884 if Nkind_In
(Exp
, N_Selected_Component
, N_Indexed_Component
)
7885 and then Has_Non_Standard_Rep
(Etype
(Prefix
(Exp
)))
7889 Set_Is_Renaming_Of_Object
(Def_Id
, False);
7892 -- Avoid generating a variable-sized temporary, by generating the
7893 -- reference just for the function call. The transformation could be
7894 -- refined to apply only when the array component is constrained by a
7897 elsif Nkind
(Exp
) = N_Selected_Component
7898 and then Nkind
(Prefix
(Exp
)) = N_Function_Call
7899 and then Is_Array_Type
(Exp_Type
)
7901 Remove_Side_Effects
(Prefix
(Exp
), Name_Req
, Variable_Ref
);
7904 -- Otherwise we generate a reference to the expression
7907 -- An expression which is in SPARK mode is considered side effect
7908 -- free if the resulting value is captured by a variable or a
7912 and then Nkind
(Parent
(Exp
)) = N_Object_Declaration
7916 -- When generating C code we cannot consider side effect free object
7917 -- declarations that have discriminants and are initialized by means
7918 -- of a function call since on this target there is no secondary
7919 -- stack to store the return value and the expander may generate an
7920 -- extra call to the function to compute the discriminant value. In
7921 -- addition, for targets that have secondary stack, the expansion of
7922 -- functions with side effects involves the generation of an access
7923 -- type to capture the return value stored in the secondary stack;
7924 -- by contrast when generating C code such expansion generates an
7925 -- internal object declaration (no access type involved) which must
7926 -- be identified here to avoid entering into a never-ending loop
7927 -- generating internal object declarations.
7929 elsif Generate_C_Code
7930 and then Nkind
(Parent
(Exp
)) = N_Object_Declaration
7932 (Nkind
(Exp
) /= N_Function_Call
7933 or else not Has_Discriminants
(Exp_Type
)
7934 or else Is_Internal_Name
7935 (Chars
(Defining_Identifier
(Parent
(Exp
)))))
7940 -- Special processing for function calls that return a limited type.
7941 -- We need to build a declaration that will enable build-in-place
7942 -- expansion of the call. This is not done if the context is already
7943 -- an object declaration, to prevent infinite recursion.
7945 -- This is relevant only in Ada 2005 mode. In Ada 95 programs we have
7946 -- to accommodate functions returning limited objects by reference.
7948 if Ada_Version
>= Ada_2005
7949 and then Nkind
(Exp
) = N_Function_Call
7950 and then Is_Limited_View
(Etype
(Exp
))
7951 and then Nkind
(Parent
(Exp
)) /= N_Object_Declaration
7954 Obj
: constant Entity_Id
:= Make_Temporary
(Loc
, 'F', Exp
);
7959 Make_Object_Declaration
(Loc
,
7960 Defining_Identifier
=> Obj
,
7961 Object_Definition
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7962 Expression
=> Relocate_Node
(Exp
));
7964 Insert_Action
(Exp
, Decl
);
7965 Set_Etype
(Obj
, Exp_Type
);
7966 Rewrite
(Exp
, New_Occurrence_Of
(Obj
, Loc
));
7971 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7973 -- The regular expansion of functions with side effects involves the
7974 -- generation of an access type to capture the return value found on
7975 -- the secondary stack. Since SPARK (and why) cannot process access
7976 -- types, use a different approach which ignores the secondary stack
7977 -- and "copies" the returned object.
7978 -- When generating C code, no need for a 'reference since the
7979 -- secondary stack is not supported.
7981 if GNATprove_Mode
or Generate_C_Code
then
7982 Res
:= New_Occurrence_Of
(Def_Id
, Loc
);
7983 Ref_Type
:= Exp_Type
;
7985 -- Regular expansion utilizing an access type and 'reference
7989 Make_Explicit_Dereference
(Loc
,
7990 Prefix
=> New_Occurrence_Of
(Def_Id
, Loc
));
7993 -- type Ann is access all <Exp_Type>;
7995 Ref_Type
:= Make_Temporary
(Loc
, 'A');
7998 Make_Full_Type_Declaration
(Loc
,
7999 Defining_Identifier
=> Ref_Type
,
8001 Make_Access_To_Object_Definition
(Loc
,
8002 All_Present
=> True,
8003 Subtype_Indication
=>
8004 New_Occurrence_Of
(Exp_Type
, Loc
)));
8006 Insert_Action
(Exp
, Ptr_Typ_Decl
);
8010 if Nkind
(E
) = N_Explicit_Dereference
then
8011 New_Exp
:= Relocate_Node
(Prefix
(E
));
8014 E
:= Relocate_Node
(E
);
8016 -- Do not generate a 'reference in SPARK mode or C generation
8017 -- since the access type is not created in the first place.
8019 if GNATprove_Mode
or Generate_C_Code
then
8022 -- Otherwise generate reference, marking the value as non-null
8023 -- since we know it cannot be null and we don't want a check.
8026 New_Exp
:= Make_Reference
(Loc
, E
);
8027 Set_Is_Known_Non_Null
(Def_Id
);
8031 if Is_Delayed_Aggregate
(E
) then
8033 -- The expansion of nested aggregates is delayed until the
8034 -- enclosing aggregate is expanded. As aggregates are often
8035 -- qualified, the predicate applies to qualified expressions as
8036 -- well, indicating that the enclosing aggregate has not been
8037 -- expanded yet. At this point the aggregate is part of a
8038 -- stand-alone declaration, and must be fully expanded.
8040 if Nkind
(E
) = N_Qualified_Expression
then
8041 Set_Expansion_Delayed
(Expression
(E
), False);
8042 Set_Analyzed
(Expression
(E
), False);
8044 Set_Expansion_Delayed
(E
, False);
8047 Set_Analyzed
(E
, False);
8050 -- Generating C code of object declarations that have discriminants
8051 -- and are initialized by means of a function call we propagate the
8052 -- discriminants of the parent type to the internally built object.
8053 -- This is needed to avoid generating an extra call to the called
8056 -- For example, if we generate here the following declaration, it
8057 -- will be expanded later adding an extra call to evaluate the value
8058 -- of the discriminant (needed to compute the size of the object).
8060 -- type Rec (D : Integer) is ...
8061 -- Obj : constant Rec := SomeFunc;
8064 and then Nkind
(Parent
(Exp
)) = N_Object_Declaration
8065 and then Has_Discriminants
(Exp_Type
)
8066 and then Nkind
(Exp
) = N_Function_Call
8069 Make_Object_Declaration
(Loc
,
8070 Defining_Identifier
=> Def_Id
,
8071 Object_Definition
=> New_Copy_Tree
8072 (Object_Definition
(Parent
(Exp
))),
8073 Constant_Present
=> True,
8074 Expression
=> New_Exp
));
8077 Make_Object_Declaration
(Loc
,
8078 Defining_Identifier
=> Def_Id
,
8079 Object_Definition
=> New_Occurrence_Of
(Ref_Type
, Loc
),
8080 Constant_Present
=> True,
8081 Expression
=> New_Exp
));
8085 -- Preserve the Assignment_OK flag in all copies, since at least one
8086 -- copy may be used in a context where this flag must be set (otherwise
8087 -- why would the flag be set in the first place).
8089 Set_Assignment_OK
(Res
, Assignment_OK
(Exp
));
8091 -- Finally rewrite the original expression and we are done
8094 Analyze_And_Resolve
(Exp
, Exp_Type
);
8097 Scope_Suppress
:= Svg_Suppress
;
8098 end Remove_Side_Effects
;
8100 ---------------------------
8101 -- Represented_As_Scalar --
8102 ---------------------------
8104 function Represented_As_Scalar
(T
: Entity_Id
) return Boolean is
8105 UT
: constant Entity_Id
:= Underlying_Type
(T
);
8107 return Is_Scalar_Type
(UT
)
8108 or else (Is_Bit_Packed_Array
(UT
)
8109 and then Is_Scalar_Type
(Packed_Array_Impl_Type
(UT
)));
8110 end Represented_As_Scalar
;
8112 ------------------------------
8113 -- Requires_Cleanup_Actions --
8114 ------------------------------
8116 function Requires_Cleanup_Actions
8118 Lib_Level
: Boolean) return Boolean
8120 At_Lib_Level
: constant Boolean :=
8122 and then Nkind_In
(N
, N_Package_Body
,
8123 N_Package_Specification
);
8124 -- N is at the library level if the top-most context is a package and
8125 -- the path taken to reach N does not inlcude non-package constructs.
8129 when N_Accept_Statement |
8137 Requires_Cleanup_Actions
(Declarations
(N
), At_Lib_Level
, True)
8139 (Present
(Handled_Statement_Sequence
(N
))
8141 Requires_Cleanup_Actions
8142 (Statements
(Handled_Statement_Sequence
(N
)),
8143 At_Lib_Level
, True));
8145 when N_Package_Specification
=>
8147 Requires_Cleanup_Actions
8148 (Visible_Declarations
(N
), At_Lib_Level
, True)
8150 Requires_Cleanup_Actions
8151 (Private_Declarations
(N
), At_Lib_Level
, True);
8156 end Requires_Cleanup_Actions
;
8158 ------------------------------
8159 -- Requires_Cleanup_Actions --
8160 ------------------------------
8162 function Requires_Cleanup_Actions
8164 Lib_Level
: Boolean;
8165 Nested_Constructs
: Boolean) return Boolean
8170 Obj_Typ
: Entity_Id
;
8171 Pack_Id
: Entity_Id
;
8176 or else Is_Empty_List
(L
)
8182 while Present
(Decl
) loop
8184 -- Library-level tagged types
8186 if Nkind
(Decl
) = N_Full_Type_Declaration
then
8187 Typ
:= Defining_Identifier
(Decl
);
8189 -- Ignored Ghost types do not need any cleanup actions because
8190 -- they will not appear in the final tree.
8192 if Is_Ignored_Ghost_Entity
(Typ
) then
8195 elsif Is_Tagged_Type
(Typ
)
8196 and then Is_Library_Level_Entity
(Typ
)
8197 and then Convention
(Typ
) = Convention_Ada
8198 and then Present
(Access_Disp_Table
(Typ
))
8199 and then RTE_Available
(RE_Unregister_Tag
)
8200 and then not Is_Abstract_Type
(Typ
)
8201 and then not No_Run_Time_Mode
8206 -- Regular object declarations
8208 elsif Nkind
(Decl
) = N_Object_Declaration
then
8209 Obj_Id
:= Defining_Identifier
(Decl
);
8210 Obj_Typ
:= Base_Type
(Etype
(Obj_Id
));
8211 Expr
:= Expression
(Decl
);
8213 -- Bypass any form of processing for objects which have their
8214 -- finalization disabled. This applies only to objects at the
8217 if Lib_Level
and then Finalize_Storage_Only
(Obj_Typ
) then
8220 -- Transient variables are treated separately in order to minimize
8221 -- the size of the generated code. See Exp_Ch7.Process_Transient_
8224 elsif Is_Processed_Transient
(Obj_Id
) then
8227 -- Ignored Ghost objects do not need any cleanup actions because
8228 -- they will not appear in the final tree.
8230 elsif Is_Ignored_Ghost_Entity
(Obj_Id
) then
8233 -- The expansion of iterator loops generates an object declaration
8234 -- where the Ekind is explicitly set to loop parameter. This is to
8235 -- ensure that the loop parameter behaves as a constant from user
8236 -- code point of view. Such object are never controlled and do not
8237 -- require cleanup actions. An iterator loop over a container of
8238 -- controlled objects does not produce such object declarations.
8240 elsif Ekind
(Obj_Id
) = E_Loop_Parameter
then
8243 -- The object is of the form:
8244 -- Obj : Typ [:= Expr];
8246 -- Do not process the incomplete view of a deferred constant. Do
8247 -- not consider tag-to-class-wide conversions.
8249 elsif not Is_Imported
(Obj_Id
)
8250 and then Needs_Finalization
(Obj_Typ
)
8251 and then not (Ekind
(Obj_Id
) = E_Constant
8252 and then not Has_Completion
(Obj_Id
))
8253 and then not Is_Tag_To_Class_Wide_Conversion
(Obj_Id
)
8257 -- The object is of the form:
8258 -- Obj : Access_Typ := Non_BIP_Function_Call'reference;
8260 -- Obj : Access_Typ :=
8261 -- BIP_Function_Call (BIPalloc => 2, ...)'reference;
8263 elsif Is_Access_Type
(Obj_Typ
)
8264 and then Needs_Finalization
8265 (Available_View
(Designated_Type
(Obj_Typ
)))
8266 and then Present
(Expr
)
8268 (Is_Secondary_Stack_BIP_Func_Call
(Expr
)
8270 (Is_Non_BIP_Func_Call
(Expr
)
8271 and then not Is_Related_To_Func_Return
(Obj_Id
)))
8275 -- Processing for "hook" objects generated for controlled
8276 -- transients declared inside an Expression_With_Actions.
8278 elsif Is_Access_Type
(Obj_Typ
)
8279 and then Present
(Status_Flag_Or_Transient_Decl
(Obj_Id
))
8280 and then Nkind
(Status_Flag_Or_Transient_Decl
(Obj_Id
)) =
8281 N_Object_Declaration
8285 -- Processing for intermediate results of if expressions where
8286 -- one of the alternatives uses a controlled function call.
8288 elsif Is_Access_Type
(Obj_Typ
)
8289 and then Present
(Status_Flag_Or_Transient_Decl
(Obj_Id
))
8290 and then Nkind
(Status_Flag_Or_Transient_Decl
(Obj_Id
)) =
8291 N_Defining_Identifier
8292 and then Present
(Expr
)
8293 and then Nkind
(Expr
) = N_Null
8297 -- Simple protected objects which use type System.Tasking.
8298 -- Protected_Objects.Protection to manage their locks should be
8299 -- treated as controlled since they require manual cleanup.
8301 elsif Ekind
(Obj_Id
) = E_Variable
8302 and then (Is_Simple_Protected_Type
(Obj_Typ
)
8303 or else Has_Simple_Protected_Object
(Obj_Typ
))
8308 -- Specific cases of object renamings
8310 elsif Nkind
(Decl
) = N_Object_Renaming_Declaration
then
8311 Obj_Id
:= Defining_Identifier
(Decl
);
8312 Obj_Typ
:= Base_Type
(Etype
(Obj_Id
));
8314 -- Bypass any form of processing for objects which have their
8315 -- finalization disabled. This applies only to objects at the
8318 if Lib_Level
and then Finalize_Storage_Only
(Obj_Typ
) then
8321 -- Ignored Ghost object renamings do not need any cleanup actions
8322 -- because they will not appear in the final tree.
8324 elsif Is_Ignored_Ghost_Entity
(Obj_Id
) then
8327 -- Return object of a build-in-place function. This case is
8328 -- recognized and marked by the expansion of an extended return
8329 -- statement (see Expand_N_Extended_Return_Statement).
8331 elsif Needs_Finalization
(Obj_Typ
)
8332 and then Is_Return_Object
(Obj_Id
)
8333 and then Present
(Status_Flag_Or_Transient_Decl
(Obj_Id
))
8337 -- Detect a case where a source object has been initialized by
8338 -- a controlled function call or another object which was later
8339 -- rewritten as a class-wide conversion of Ada.Tags.Displace.
8341 -- Obj1 : CW_Type := Src_Obj;
8342 -- Obj2 : CW_Type := Function_Call (...);
8344 -- Obj1 : CW_Type renames (... Ada.Tags.Displace (Src_Obj));
8345 -- Tmp : ... := Function_Call (...)'reference;
8346 -- Obj2 : CW_Type renames (... Ada.Tags.Displace (Tmp));
8348 elsif Is_Displacement_Of_Object_Or_Function_Result
(Obj_Id
) then
8352 -- Inspect the freeze node of an access-to-controlled type and look
8353 -- for a delayed finalization master. This case arises when the
8354 -- freeze actions are inserted at a later time than the expansion of
8355 -- the context. Since Build_Finalizer is never called on a single
8356 -- construct twice, the master will be ultimately left out and never
8357 -- finalized. This is also needed for freeze actions of designated
8358 -- types themselves, since in some cases the finalization master is
8359 -- associated with a designated type's freeze node rather than that
8360 -- of the access type (see handling for freeze actions in
8361 -- Build_Finalization_Master).
8363 elsif Nkind
(Decl
) = N_Freeze_Entity
8364 and then Present
(Actions
(Decl
))
8366 Typ
:= Entity
(Decl
);
8368 -- Freeze nodes for ignored Ghost types do not need cleanup
8369 -- actions because they will never appear in the final tree.
8371 if Is_Ignored_Ghost_Entity
(Typ
) then
8374 elsif ((Is_Access_Type
(Typ
)
8375 and then not Is_Access_Subprogram_Type
(Typ
)
8376 and then Needs_Finalization
8377 (Available_View
(Designated_Type
(Typ
))))
8378 or else (Is_Type
(Typ
) and then Needs_Finalization
(Typ
)))
8379 and then Requires_Cleanup_Actions
8380 (Actions
(Decl
), Lib_Level
, Nested_Constructs
)
8385 -- Nested package declarations
8387 elsif Nested_Constructs
8388 and then Nkind
(Decl
) = N_Package_Declaration
8390 Pack_Id
:= Defining_Entity
(Decl
);
8392 -- Do not inspect an ignored Ghost package because all code found
8393 -- within will not appear in the final tree.
8395 if Is_Ignored_Ghost_Entity
(Pack_Id
) then
8398 elsif Ekind
(Pack_Id
) /= E_Generic_Package
8399 and then Requires_Cleanup_Actions
8400 (Specification
(Decl
), Lib_Level
)
8405 -- Nested package bodies
8407 elsif Nested_Constructs
and then Nkind
(Decl
) = N_Package_Body
then
8409 -- Do not inspect an ignored Ghost package body because all code
8410 -- found within will not appear in the final tree.
8412 if Is_Ignored_Ghost_Entity
(Defining_Entity
(Decl
)) then
8415 elsif Ekind
(Corresponding_Spec
(Decl
)) /= E_Generic_Package
8416 and then Requires_Cleanup_Actions
(Decl
, Lib_Level
)
8421 elsif Nkind
(Decl
) = N_Block_Statement
8424 -- Handle a rare case caused by a controlled transient variable
8425 -- created as part of a record init proc. The variable is wrapped
8426 -- in a block, but the block is not associated with a transient
8431 -- Handle the case where the original context has been wrapped in
8432 -- a block to avoid interference between exception handlers and
8433 -- At_End handlers. Treat the block as transparent and process its
8436 or else Is_Finalization_Wrapper
(Decl
))
8438 if Requires_Cleanup_Actions
(Decl
, Lib_Level
) then
8447 end Requires_Cleanup_Actions
;
8449 ------------------------------------
8450 -- Safe_Unchecked_Type_Conversion --
8451 ------------------------------------
8453 -- Note: this function knows quite a bit about the exact requirements of
8454 -- Gigi with respect to unchecked type conversions, and its code must be
8455 -- coordinated with any changes in Gigi in this area.
8457 -- The above requirements should be documented in Sinfo ???
8459 function Safe_Unchecked_Type_Conversion
(Exp
: Node_Id
) return Boolean is
8464 Pexp
: constant Node_Id
:= Parent
(Exp
);
8467 -- If the expression is the RHS of an assignment or object declaration
8468 -- we are always OK because there will always be a target.
8470 -- Object renaming declarations, (generated for view conversions of
8471 -- actuals in inlined calls), like object declarations, provide an
8472 -- explicit type, and are safe as well.
8474 if (Nkind
(Pexp
) = N_Assignment_Statement
8475 and then Expression
(Pexp
) = Exp
)
8476 or else Nkind_In
(Pexp
, N_Object_Declaration
,
8477 N_Object_Renaming_Declaration
)
8481 -- If the expression is the prefix of an N_Selected_Component we should
8482 -- also be OK because GCC knows to look inside the conversion except if
8483 -- the type is discriminated. We assume that we are OK anyway if the
8484 -- type is not set yet or if it is controlled since we can't afford to
8485 -- introduce a temporary in this case.
8487 elsif Nkind
(Pexp
) = N_Selected_Component
8488 and then Prefix
(Pexp
) = Exp
8490 if No
(Etype
(Pexp
)) then
8494 not Has_Discriminants
(Etype
(Pexp
))
8495 or else Is_Constrained
(Etype
(Pexp
));
8499 -- Set the output type, this comes from Etype if it is set, otherwise we
8500 -- take it from the subtype mark, which we assume was already fully
8503 if Present
(Etype
(Exp
)) then
8504 Otyp
:= Etype
(Exp
);
8506 Otyp
:= Entity
(Subtype_Mark
(Exp
));
8509 -- The input type always comes from the expression, and we assume this
8510 -- is indeed always analyzed, so we can simply get the Etype.
8512 Ityp
:= Etype
(Expression
(Exp
));
8514 -- Initialize alignments to unknown so far
8519 -- Replace a concurrent type by its corresponding record type and each
8520 -- type by its underlying type and do the tests on those. The original
8521 -- type may be a private type whose completion is a concurrent type, so
8522 -- find the underlying type first.
8524 if Present
(Underlying_Type
(Otyp
)) then
8525 Otyp
:= Underlying_Type
(Otyp
);
8528 if Present
(Underlying_Type
(Ityp
)) then
8529 Ityp
:= Underlying_Type
(Ityp
);
8532 if Is_Concurrent_Type
(Otyp
) then
8533 Otyp
:= Corresponding_Record_Type
(Otyp
);
8536 if Is_Concurrent_Type
(Ityp
) then
8537 Ityp
:= Corresponding_Record_Type
(Ityp
);
8540 -- If the base types are the same, we know there is no problem since
8541 -- this conversion will be a noop.
8543 if Implementation_Base_Type
(Otyp
) = Implementation_Base_Type
(Ityp
) then
8546 -- Same if this is an upwards conversion of an untagged type, and there
8547 -- are no constraints involved (could be more general???)
8549 elsif Etype
(Ityp
) = Otyp
8550 and then not Is_Tagged_Type
(Ityp
)
8551 and then not Has_Discriminants
(Ityp
)
8552 and then No
(First_Rep_Item
(Base_Type
(Ityp
)))
8556 -- If the expression has an access type (object or subprogram) we assume
8557 -- that the conversion is safe, because the size of the target is safe,
8558 -- even if it is a record (which might be treated as having unknown size
8561 elsif Is_Access_Type
(Ityp
) then
8564 -- If the size of output type is known at compile time, there is never
8565 -- a problem. Note that unconstrained records are considered to be of
8566 -- known size, but we can't consider them that way here, because we are
8567 -- talking about the actual size of the object.
8569 -- We also make sure that in addition to the size being known, we do not
8570 -- have a case which might generate an embarrassingly large temp in
8571 -- stack checking mode.
8573 elsif Size_Known_At_Compile_Time
(Otyp
)
8575 (not Stack_Checking_Enabled
8576 or else not May_Generate_Large_Temp
(Otyp
))
8577 and then not (Is_Record_Type
(Otyp
) and then not Is_Constrained
(Otyp
))
8581 -- If either type is tagged, then we know the alignment is OK so Gigi
8582 -- will be able to use pointer punning.
8584 elsif Is_Tagged_Type
(Otyp
) or else Is_Tagged_Type
(Ityp
) then
8587 -- If either type is a limited record type, we cannot do a copy, so say
8588 -- safe since there's nothing else we can do.
8590 elsif Is_Limited_Record
(Otyp
) or else Is_Limited_Record
(Ityp
) then
8593 -- Conversions to and from packed array types are always ignored and
8596 elsif Is_Packed_Array_Impl_Type
(Otyp
)
8597 or else Is_Packed_Array_Impl_Type
(Ityp
)
8602 -- The only other cases known to be safe is if the input type's
8603 -- alignment is known to be at least the maximum alignment for the
8604 -- target or if both alignments are known and the output type's
8605 -- alignment is no stricter than the input's. We can use the component
8606 -- type alignement for an array if a type is an unpacked array type.
8608 if Present
(Alignment_Clause
(Otyp
)) then
8609 Oalign
:= Expr_Value
(Expression
(Alignment_Clause
(Otyp
)));
8611 elsif Is_Array_Type
(Otyp
)
8612 and then Present
(Alignment_Clause
(Component_Type
(Otyp
)))
8614 Oalign
:= Expr_Value
(Expression
(Alignment_Clause
8615 (Component_Type
(Otyp
))));
8618 if Present
(Alignment_Clause
(Ityp
)) then
8619 Ialign
:= Expr_Value
(Expression
(Alignment_Clause
(Ityp
)));
8621 elsif Is_Array_Type
(Ityp
)
8622 and then Present
(Alignment_Clause
(Component_Type
(Ityp
)))
8624 Ialign
:= Expr_Value
(Expression
(Alignment_Clause
8625 (Component_Type
(Ityp
))));
8628 if Ialign
/= No_Uint
and then Ialign
> Maximum_Alignment
then
8631 elsif Ialign
/= No_Uint
8632 and then Oalign
/= No_Uint
8633 and then Ialign
<= Oalign
8637 -- Otherwise, Gigi cannot handle this and we must make a temporary
8642 end Safe_Unchecked_Type_Conversion
;
8644 ---------------------------------
8645 -- Set_Current_Value_Condition --
8646 ---------------------------------
8648 -- Note: the implementation of this procedure is very closely tied to the
8649 -- implementation of Get_Current_Value_Condition. Here we set required
8650 -- Current_Value fields, and in Get_Current_Value_Condition, we interpret
8651 -- them, so they must have a consistent view.
8653 procedure Set_Current_Value_Condition
(Cnode
: Node_Id
) is
8655 procedure Set_Entity_Current_Value
(N
: Node_Id
);
8656 -- If N is an entity reference, where the entity is of an appropriate
8657 -- kind, then set the current value of this entity to Cnode, unless
8658 -- there is already a definite value set there.
8660 procedure Set_Expression_Current_Value
(N
: Node_Id
);
8661 -- If N is of an appropriate form, sets an appropriate entry in current
8662 -- value fields of relevant entities. Multiple entities can be affected
8663 -- in the case of an AND or AND THEN.
8665 ------------------------------
8666 -- Set_Entity_Current_Value --
8667 ------------------------------
8669 procedure Set_Entity_Current_Value
(N
: Node_Id
) is
8671 if Is_Entity_Name
(N
) then
8673 Ent
: constant Entity_Id
:= Entity
(N
);
8676 -- Don't capture if not safe to do so
8678 if not Safe_To_Capture_Value
(N
, Ent
, Cond
=> True) then
8682 -- Here we have a case where the Current_Value field may need
8683 -- to be set. We set it if it is not already set to a compile
8684 -- time expression value.
8686 -- Note that this represents a decision that one condition
8687 -- blots out another previous one. That's certainly right if
8688 -- they occur at the same level. If the second one is nested,
8689 -- then the decision is neither right nor wrong (it would be
8690 -- equally OK to leave the outer one in place, or take the new
8691 -- inner one. Really we should record both, but our data
8692 -- structures are not that elaborate.
8694 if Nkind
(Current_Value
(Ent
)) not in N_Subexpr
then
8695 Set_Current_Value
(Ent
, Cnode
);
8699 end Set_Entity_Current_Value
;
8701 ----------------------------------
8702 -- Set_Expression_Current_Value --
8703 ----------------------------------
8705 procedure Set_Expression_Current_Value
(N
: Node_Id
) is
8711 -- Loop to deal with (ignore for now) any NOT operators present. The
8712 -- presence of NOT operators will be handled properly when we call
8713 -- Get_Current_Value_Condition.
8715 while Nkind
(Cond
) = N_Op_Not
loop
8716 Cond
:= Right_Opnd
(Cond
);
8719 -- For an AND or AND THEN, recursively process operands
8721 if Nkind
(Cond
) = N_Op_And
or else Nkind
(Cond
) = N_And_Then
then
8722 Set_Expression_Current_Value
(Left_Opnd
(Cond
));
8723 Set_Expression_Current_Value
(Right_Opnd
(Cond
));
8727 -- Check possible relational operator
8729 if Nkind
(Cond
) in N_Op_Compare
then
8730 if Compile_Time_Known_Value
(Right_Opnd
(Cond
)) then
8731 Set_Entity_Current_Value
(Left_Opnd
(Cond
));
8732 elsif Compile_Time_Known_Value
(Left_Opnd
(Cond
)) then
8733 Set_Entity_Current_Value
(Right_Opnd
(Cond
));
8736 elsif Nkind_In
(Cond
,
8738 N_Qualified_Expression
,
8739 N_Expression_With_Actions
)
8741 Set_Expression_Current_Value
(Expression
(Cond
));
8743 -- Check possible boolean variable reference
8746 Set_Entity_Current_Value
(Cond
);
8748 end Set_Expression_Current_Value
;
8750 -- Start of processing for Set_Current_Value_Condition
8753 Set_Expression_Current_Value
(Condition
(Cnode
));
8754 end Set_Current_Value_Condition
;
8756 --------------------------
8757 -- Set_Elaboration_Flag --
8758 --------------------------
8760 procedure Set_Elaboration_Flag
(N
: Node_Id
; Spec_Id
: Entity_Id
) is
8761 Loc
: constant Source_Ptr
:= Sloc
(N
);
8762 Ent
: constant Entity_Id
:= Elaboration_Entity
(Spec_Id
);
8766 if Present
(Ent
) then
8768 -- Nothing to do if at the compilation unit level, because in this
8769 -- case the flag is set by the binder generated elaboration routine.
8771 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
8774 -- Here we do need to generate an assignment statement
8777 Check_Restriction
(No_Elaboration_Code
, N
);
8779 Make_Assignment_Statement
(Loc
,
8780 Name
=> New_Occurrence_Of
(Ent
, Loc
),
8781 Expression
=> Make_Integer_Literal
(Loc
, Uint_1
));
8783 if Nkind
(Parent
(N
)) = N_Subunit
then
8784 Insert_After
(Corresponding_Stub
(Parent
(N
)), Asn
);
8786 Insert_After
(N
, Asn
);
8791 -- Kill current value indication. This is necessary because the
8792 -- tests of this flag are inserted out of sequence and must not
8793 -- pick up bogus indications of the wrong constant value.
8795 Set_Current_Value
(Ent
, Empty
);
8797 -- If the subprogram is in the current declarative part and
8798 -- 'access has been applied to it, generate an elaboration
8799 -- check at the beginning of the declarations of the body.
8801 if Nkind
(N
) = N_Subprogram_Body
8802 and then Address_Taken
(Spec_Id
)
8804 Ekind_In
(Scope
(Spec_Id
), E_Block
, E_Procedure
, E_Function
)
8807 Loc
: constant Source_Ptr
:= Sloc
(N
);
8808 Decls
: constant List_Id
:= Declarations
(N
);
8812 -- No need to generate this check if first entry in the
8813 -- declaration list is a raise of Program_Error now.
8816 and then Nkind
(First
(Decls
)) = N_Raise_Program_Error
8821 -- Otherwise generate the check
8824 Make_Raise_Program_Error
(Loc
,
8827 Left_Opnd
=> New_Occurrence_Of
(Ent
, Loc
),
8828 Right_Opnd
=> Make_Integer_Literal
(Loc
, Uint_0
)),
8829 Reason
=> PE_Access_Before_Elaboration
);
8832 Set_Declarations
(N
, New_List
(Chk
));
8834 Prepend
(Chk
, Decls
);
8842 end Set_Elaboration_Flag
;
8844 ----------------------------
8845 -- Set_Renamed_Subprogram --
8846 ----------------------------
8848 procedure Set_Renamed_Subprogram
(N
: Node_Id
; E
: Entity_Id
) is
8850 -- If input node is an identifier, we can just reset it
8852 if Nkind
(N
) = N_Identifier
then
8853 Set_Chars
(N
, Chars
(E
));
8856 -- Otherwise we have to do a rewrite, preserving Comes_From_Source
8860 CS
: constant Boolean := Comes_From_Source
(N
);
8862 Rewrite
(N
, Make_Identifier
(Sloc
(N
), Chars
(E
)));
8864 Set_Comes_From_Source
(N
, CS
);
8865 Set_Analyzed
(N
, True);
8868 end Set_Renamed_Subprogram
;
8870 ----------------------
8871 -- Side_Effect_Free --
8872 ----------------------
8874 function Side_Effect_Free
8876 Name_Req
: Boolean := False;
8877 Variable_Ref
: Boolean := False) return Boolean
8879 Typ
: constant Entity_Id
:= Etype
(N
);
8880 -- Result type of the expression
8882 function Safe_Prefixed_Reference
(N
: Node_Id
) return Boolean;
8883 -- The argument N is a construct where the Prefix is dereferenced if it
8884 -- is an access type and the result is a variable. The call returns True
8885 -- if the construct is side effect free (not considering side effects in
8886 -- other than the prefix which are to be tested by the caller).
8888 function Within_In_Parameter
(N
: Node_Id
) return Boolean;
8889 -- Determines if N is a subcomponent of a composite in-parameter. If so,
8890 -- N is not side-effect free when the actual is global and modifiable
8891 -- indirectly from within a subprogram, because it may be passed by
8892 -- reference. The front-end must be conservative here and assume that
8893 -- this may happen with any array or record type. On the other hand, we
8894 -- cannot create temporaries for all expressions for which this
8895 -- condition is true, for various reasons that might require clearing up
8896 -- ??? For example, discriminant references that appear out of place, or
8897 -- spurious type errors with class-wide expressions. As a result, we
8898 -- limit the transformation to loop bounds, which is so far the only
8899 -- case that requires it.
8901 -----------------------------
8902 -- Safe_Prefixed_Reference --
8903 -----------------------------
8905 function Safe_Prefixed_Reference
(N
: Node_Id
) return Boolean is
8907 -- If prefix is not side effect free, definitely not safe
8909 if not Side_Effect_Free
(Prefix
(N
), Name_Req
, Variable_Ref
) then
8912 -- If the prefix is of an access type that is not access-to-constant,
8913 -- then this construct is a variable reference, which means it is to
8914 -- be considered to have side effects if Variable_Ref is set True.
8916 elsif Is_Access_Type
(Etype
(Prefix
(N
)))
8917 and then not Is_Access_Constant
(Etype
(Prefix
(N
)))
8918 and then Variable_Ref
8920 -- Exception is a prefix that is the result of a previous removal
8923 return Is_Entity_Name
(Prefix
(N
))
8924 and then not Comes_From_Source
(Prefix
(N
))
8925 and then Ekind
(Entity
(Prefix
(N
))) = E_Constant
8926 and then Is_Internal_Name
(Chars
(Entity
(Prefix
(N
))));
8928 -- If the prefix is an explicit dereference then this construct is a
8929 -- variable reference, which means it is to be considered to have
8930 -- side effects if Variable_Ref is True.
8932 -- We do NOT exclude dereferences of access-to-constant types because
8933 -- we handle them as constant view of variables.
8935 elsif Nkind
(Prefix
(N
)) = N_Explicit_Dereference
8936 and then Variable_Ref
8940 -- Note: The following test is the simplest way of solving a complex
8941 -- problem uncovered by the following test (Side effect on loop bound
8942 -- that is a subcomponent of a global variable:
8944 -- with Text_Io; use Text_Io;
8945 -- procedure Tloop is
8948 -- V : Natural := 4;
8949 -- S : String (1..5) := (others => 'a');
8956 -- with procedure Action;
8957 -- procedure Loop_G (Arg : X; Msg : String)
8959 -- procedure Loop_G (Arg : X; Msg : String) is
8961 -- Put_Line ("begin loop_g " & Msg & " will loop till: "
8962 -- & Natural'Image (Arg.V));
8963 -- for Index in 1 .. Arg.V loop
8965 -- (Natural'Image (Index) & " " & Arg.S (Index));
8966 -- if Index > 2 then
8970 -- Put_Line ("end loop_g " & Msg);
8973 -- procedure Loop1 is new Loop_G (Modi);
8974 -- procedure Modi is
8977 -- Loop1 (X1, "from modi");
8981 -- Loop1 (X1, "initial");
8984 -- The output of the above program should be:
8986 -- begin loop_g initial will loop till: 4
8990 -- begin loop_g from modi will loop till: 1
8992 -- end loop_g from modi
8994 -- begin loop_g from modi will loop till: 1
8996 -- end loop_g from modi
8997 -- end loop_g initial
8999 -- If a loop bound is a subcomponent of a global variable, a
9000 -- modification of that variable within the loop may incorrectly
9001 -- affect the execution of the loop.
9003 elsif Nkind
(Parent
(Parent
(N
))) = N_Loop_Parameter_Specification
9004 and then Within_In_Parameter
(Prefix
(N
))
9005 and then Variable_Ref
9009 -- All other cases are side effect free
9014 end Safe_Prefixed_Reference
;
9016 -------------------------
9017 -- Within_In_Parameter --
9018 -------------------------
9020 function Within_In_Parameter
(N
: Node_Id
) return Boolean is
9022 if not Comes_From_Source
(N
) then
9025 elsif Is_Entity_Name
(N
) then
9026 return Ekind
(Entity
(N
)) = E_In_Parameter
;
9028 elsif Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
9029 return Within_In_Parameter
(Prefix
(N
));
9034 end Within_In_Parameter
;
9036 -- Start of processing for Side_Effect_Free
9039 -- If volatile reference, always consider it to have side effects
9041 if Is_Volatile_Reference
(N
) then
9045 -- Note on checks that could raise Constraint_Error. Strictly, if we
9046 -- take advantage of 11.6, these checks do not count as side effects.
9047 -- However, we would prefer to consider that they are side effects,
9048 -- since the backend CSE does not work very well on expressions which
9049 -- can raise Constraint_Error. On the other hand if we don't consider
9050 -- them to be side effect free, then we get some awkward expansions
9051 -- in -gnato mode, resulting in code insertions at a point where we
9052 -- do not have a clear model for performing the insertions.
9054 -- Special handling for entity names
9056 if Is_Entity_Name
(N
) then
9058 -- A type reference is always side effect free
9060 if Is_Type
(Entity
(N
)) then
9063 -- Variables are considered to be a side effect if Variable_Ref
9064 -- is set or if we have a volatile reference and Name_Req is off.
9065 -- If Name_Req is True then we can't help returning a name which
9066 -- effectively allows multiple references in any case.
9068 elsif Is_Variable
(N
, Use_Original_Node
=> False) then
9069 return not Variable_Ref
9070 and then (not Is_Volatile_Reference
(N
) or else Name_Req
);
9072 -- Any other entity (e.g. a subtype name) is definitely side
9079 -- A value known at compile time is always side effect free
9081 elsif Compile_Time_Known_Value
(N
) then
9084 -- A variable renaming is not side-effect free, because the renaming
9085 -- will function like a macro in the front-end in some cases, and an
9086 -- assignment can modify the component designated by N, so we need to
9087 -- create a temporary for it.
9089 -- The guard testing for Entity being present is needed at least in
9090 -- the case of rewritten predicate expressions, and may well also be
9091 -- appropriate elsewhere. Obviously we can't go testing the entity
9092 -- field if it does not exist, so it's reasonable to say that this is
9093 -- not the renaming case if it does not exist.
9095 elsif Is_Entity_Name
(Original_Node
(N
))
9096 and then Present
(Entity
(Original_Node
(N
)))
9097 and then Is_Renaming_Of_Object
(Entity
(Original_Node
(N
)))
9098 and then Ekind
(Entity
(Original_Node
(N
))) /= E_Constant
9101 RO
: constant Node_Id
:=
9102 Renamed_Object
(Entity
(Original_Node
(N
)));
9105 -- If the renamed object is an indexed component, or an
9106 -- explicit dereference, then the designated object could
9107 -- be modified by an assignment.
9109 if Nkind_In
(RO
, N_Indexed_Component
,
9110 N_Explicit_Dereference
)
9114 -- A selected component must have a safe prefix
9116 elsif Nkind
(RO
) = N_Selected_Component
then
9117 return Safe_Prefixed_Reference
(RO
);
9119 -- In all other cases, designated object cannot be changed so
9120 -- we are side effect free.
9127 -- Remove_Side_Effects generates an object renaming declaration to
9128 -- capture the expression of a class-wide expression. In VM targets
9129 -- the frontend performs no expansion for dispatching calls to
9130 -- class- wide types since they are handled by the VM. Hence, we must
9131 -- locate here if this node corresponds to a previous invocation of
9132 -- Remove_Side_Effects to avoid a never ending loop in the frontend.
9134 elsif not Tagged_Type_Expansion
9135 and then not Comes_From_Source
(N
)
9136 and then Nkind
(Parent
(N
)) = N_Object_Renaming_Declaration
9137 and then Is_Class_Wide_Type
(Typ
)
9141 -- Generating C the type conversion of an access to constrained array
9142 -- type into an access to unconstrained array type involves initializing
9143 -- a fat pointer and the expression cannot be assumed to be free of side
9144 -- effects since it must referenced several times to compute its bounds.
9146 elsif Generate_C_Code
9147 and then Nkind
(N
) = N_Type_Conversion
9148 and then Is_Access_Type
(Typ
)
9149 and then Is_Array_Type
(Designated_Type
(Typ
))
9150 and then not Is_Constrained
(Designated_Type
(Typ
))
9155 -- For other than entity names and compile time known values,
9156 -- check the node kind for special processing.
9160 -- An attribute reference is side effect free if its expressions
9161 -- are side effect free and its prefix is side effect free or
9162 -- is an entity reference.
9164 -- Is this right? what about x'first where x is a variable???
9166 when N_Attribute_Reference
=>
9167 return Side_Effect_Free
(Expressions
(N
), Name_Req
, Variable_Ref
)
9168 and then Attribute_Name
(N
) /= Name_Input
9169 and then (Is_Entity_Name
(Prefix
(N
))
9170 or else Side_Effect_Free
9171 (Prefix
(N
), Name_Req
, Variable_Ref
));
9173 -- A binary operator is side effect free if and both operands are
9174 -- side effect free. For this purpose binary operators include
9175 -- membership tests and short circuit forms.
9177 when N_Binary_Op | N_Membership_Test | N_Short_Circuit
=>
9178 return Side_Effect_Free
(Left_Opnd
(N
), Name_Req
, Variable_Ref
)
9180 Side_Effect_Free
(Right_Opnd
(N
), Name_Req
, Variable_Ref
);
9182 -- An explicit dereference is side effect free only if it is
9183 -- a side effect free prefixed reference.
9185 when N_Explicit_Dereference
=>
9186 return Safe_Prefixed_Reference
(N
);
9188 -- An expression with action is side effect free if its expression
9189 -- is side effect free and it has no actions.
9191 when N_Expression_With_Actions
=>
9192 return Is_Empty_List
(Actions
(N
))
9194 Side_Effect_Free
(Expression
(N
), Name_Req
, Variable_Ref
);
9196 -- A call to _rep_to_pos is side effect free, since we generate
9197 -- this pure function call ourselves. Moreover it is critically
9198 -- important to make this exception, since otherwise we can have
9199 -- discriminants in array components which don't look side effect
9200 -- free in the case of an array whose index type is an enumeration
9201 -- type with an enumeration rep clause.
9203 -- All other function calls are not side effect free
9205 when N_Function_Call
=>
9206 return Nkind
(Name
(N
)) = N_Identifier
9207 and then Is_TSS
(Name
(N
), TSS_Rep_To_Pos
)
9210 (First
(Parameter_Associations
(N
)), Name_Req
, Variable_Ref
);
9212 -- An IF expression is side effect free if it's of a scalar type, and
9213 -- all its components are all side effect free (conditions and then
9214 -- actions and else actions). We restrict to scalar types, since it
9215 -- is annoying to deal with things like (if A then B else C)'First
9216 -- where the type involved is a string type.
9218 when N_If_Expression
=>
9219 return Is_Scalar_Type
(Typ
)
9221 Side_Effect_Free
(Expressions
(N
), Name_Req
, Variable_Ref
);
9223 -- An indexed component is side effect free if it is a side
9224 -- effect free prefixed reference and all the indexing
9225 -- expressions are side effect free.
9227 when N_Indexed_Component
=>
9228 return Side_Effect_Free
(Expressions
(N
), Name_Req
, Variable_Ref
)
9229 and then Safe_Prefixed_Reference
(N
);
9231 -- A type qualification is side effect free if the expression
9232 -- is side effect free.
9234 when N_Qualified_Expression
=>
9235 return Side_Effect_Free
(Expression
(N
), Name_Req
, Variable_Ref
);
9237 -- A selected component is side effect free only if it is a side
9238 -- effect free prefixed reference.
9240 when N_Selected_Component
=>
9241 return Safe_Prefixed_Reference
(N
);
9243 -- A range is side effect free if the bounds are side effect free
9246 return Side_Effect_Free
(Low_Bound
(N
), Name_Req
, Variable_Ref
)
9248 Side_Effect_Free
(High_Bound
(N
), Name_Req
, Variable_Ref
);
9250 -- A slice is side effect free if it is a side effect free
9251 -- prefixed reference and the bounds are side effect free.
9254 return Side_Effect_Free
9255 (Discrete_Range
(N
), Name_Req
, Variable_Ref
)
9256 and then Safe_Prefixed_Reference
(N
);
9258 -- A type conversion is side effect free if the expression to be
9259 -- converted is side effect free.
9261 when N_Type_Conversion
=>
9262 return Side_Effect_Free
(Expression
(N
), Name_Req
, Variable_Ref
);
9264 -- A unary operator is side effect free if the operand
9265 -- is side effect free.
9268 return Side_Effect_Free
(Right_Opnd
(N
), Name_Req
, Variable_Ref
);
9270 -- An unchecked type conversion is side effect free only if it
9271 -- is safe and its argument is side effect free.
9273 when N_Unchecked_Type_Conversion
=>
9274 return Safe_Unchecked_Type_Conversion
(N
)
9276 Side_Effect_Free
(Expression
(N
), Name_Req
, Variable_Ref
);
9278 -- An unchecked expression is side effect free if its expression
9279 -- is side effect free.
9281 when N_Unchecked_Expression
=>
9282 return Side_Effect_Free
(Expression
(N
), Name_Req
, Variable_Ref
);
9284 -- A literal is side effect free
9286 when N_Character_Literal |
9292 -- We consider that anything else has side effects. This is a bit
9293 -- crude, but we are pretty close for most common cases, and we
9294 -- are certainly correct (i.e. we never return True when the
9295 -- answer should be False).
9300 end Side_Effect_Free
;
9302 -- A list is side effect free if all elements of the list are side
9305 function Side_Effect_Free
9307 Name_Req
: Boolean := False;
9308 Variable_Ref
: Boolean := False) return Boolean
9313 if L
= No_List
or else L
= Error_List
then
9318 while Present
(N
) loop
9319 if not Side_Effect_Free
(N
, Name_Req
, Variable_Ref
) then
9328 end Side_Effect_Free
;
9330 ----------------------------------
9331 -- Silly_Boolean_Array_Not_Test --
9332 ----------------------------------
9334 -- This procedure implements an odd and silly test. We explicitly check
9335 -- for the case where the 'First of the component type is equal to the
9336 -- 'Last of this component type, and if this is the case, we make sure
9337 -- that constraint error is raised. The reason is that the NOT is bound
9338 -- to cause CE in this case, and we will not otherwise catch it.
9340 -- No such check is required for AND and OR, since for both these cases
9341 -- False op False = False, and True op True = True. For the XOR case,
9342 -- see Silly_Boolean_Array_Xor_Test.
9344 -- Believe it or not, this was reported as a bug. Note that nearly always,
9345 -- the test will evaluate statically to False, so the code will be
9346 -- statically removed, and no extra overhead caused.
9348 procedure Silly_Boolean_Array_Not_Test
(N
: Node_Id
; T
: Entity_Id
) is
9349 Loc
: constant Source_Ptr
:= Sloc
(N
);
9350 CT
: constant Entity_Id
:= Component_Type
(T
);
9353 -- The check we install is
9355 -- constraint_error when
9356 -- component_type'first = component_type'last
9357 -- and then array_type'Length /= 0)
9359 -- We need the last guard because we don't want to raise CE for empty
9360 -- arrays since no out of range values result. (Empty arrays with a
9361 -- component type of True .. True -- very useful -- even the ACATS
9362 -- does not test that marginal case).
9365 Make_Raise_Constraint_Error
(Loc
,
9371 Make_Attribute_Reference
(Loc
,
9372 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
9373 Attribute_Name
=> Name_First
),
9376 Make_Attribute_Reference
(Loc
,
9377 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
9378 Attribute_Name
=> Name_Last
)),
9380 Right_Opnd
=> Make_Non_Empty_Check
(Loc
, Right_Opnd
(N
))),
9381 Reason
=> CE_Range_Check_Failed
));
9382 end Silly_Boolean_Array_Not_Test
;
9384 ----------------------------------
9385 -- Silly_Boolean_Array_Xor_Test --
9386 ----------------------------------
9388 -- This procedure implements an odd and silly test. We explicitly check
9389 -- for the XOR case where the component type is True .. True, since this
9390 -- will raise constraint error. A special check is required since CE
9391 -- will not be generated otherwise (cf Expand_Packed_Not).
9393 -- No such check is required for AND and OR, since for both these cases
9394 -- False op False = False, and True op True = True, and no check is
9395 -- required for the case of False .. False, since False xor False = False.
9396 -- See also Silly_Boolean_Array_Not_Test
9398 procedure Silly_Boolean_Array_Xor_Test
(N
: Node_Id
; T
: Entity_Id
) is
9399 Loc
: constant Source_Ptr
:= Sloc
(N
);
9400 CT
: constant Entity_Id
:= Component_Type
(T
);
9403 -- The check we install is
9405 -- constraint_error when
9406 -- Boolean (component_type'First)
9407 -- and then Boolean (component_type'Last)
9408 -- and then array_type'Length /= 0)
9410 -- We need the last guard because we don't want to raise CE for empty
9411 -- arrays since no out of range values result (Empty arrays with a
9412 -- component type of True .. True -- very useful -- even the ACATS
9413 -- does not test that marginal case).
9416 Make_Raise_Constraint_Error
(Loc
,
9422 Convert_To
(Standard_Boolean
,
9423 Make_Attribute_Reference
(Loc
,
9424 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
9425 Attribute_Name
=> Name_First
)),
9428 Convert_To
(Standard_Boolean
,
9429 Make_Attribute_Reference
(Loc
,
9430 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
9431 Attribute_Name
=> Name_Last
))),
9433 Right_Opnd
=> Make_Non_Empty_Check
(Loc
, Right_Opnd
(N
))),
9434 Reason
=> CE_Range_Check_Failed
));
9435 end Silly_Boolean_Array_Xor_Test
;
9437 --------------------------
9438 -- Target_Has_Fixed_Ops --
9439 --------------------------
9441 Integer_Sized_Small
: Ureal
;
9442 -- Set to 2.0 ** -(Integer'Size - 1) the first time that this function is
9443 -- called (we don't want to compute it more than once).
9445 Long_Integer_Sized_Small
: Ureal
;
9446 -- Set to 2.0 ** -(Long_Integer'Size - 1) the first time that this function
9447 -- is called (we don't want to compute it more than once)
9449 First_Time_For_THFO
: Boolean := True;
9450 -- Set to False after first call (if Fractional_Fixed_Ops_On_Target)
9452 function Target_Has_Fixed_Ops
9453 (Left_Typ
: Entity_Id
;
9454 Right_Typ
: Entity_Id
;
9455 Result_Typ
: Entity_Id
) return Boolean
9457 function Is_Fractional_Type
(Typ
: Entity_Id
) return Boolean;
9458 -- Return True if the given type is a fixed-point type with a small
9459 -- value equal to 2 ** (-(T'Object_Size - 1)) and whose values have
9460 -- an absolute value less than 1.0. This is currently limited to
9461 -- fixed-point types that map to Integer or Long_Integer.
9463 ------------------------
9464 -- Is_Fractional_Type --
9465 ------------------------
9467 function Is_Fractional_Type
(Typ
: Entity_Id
) return Boolean is
9469 if Esize
(Typ
) = Standard_Integer_Size
then
9470 return Small_Value
(Typ
) = Integer_Sized_Small
;
9472 elsif Esize
(Typ
) = Standard_Long_Integer_Size
then
9473 return Small_Value
(Typ
) = Long_Integer_Sized_Small
;
9478 end Is_Fractional_Type
;
9480 -- Start of processing for Target_Has_Fixed_Ops
9483 -- Return False if Fractional_Fixed_Ops_On_Target is false
9485 if not Fractional_Fixed_Ops_On_Target
then
9489 -- Here the target has Fractional_Fixed_Ops, if first time, compute
9490 -- standard constants used by Is_Fractional_Type.
9492 if First_Time_For_THFO
then
9493 First_Time_For_THFO
:= False;
9495 Integer_Sized_Small
:=
9498 Den
=> UI_From_Int
(Standard_Integer_Size
- 1),
9501 Long_Integer_Sized_Small
:=
9504 Den
=> UI_From_Int
(Standard_Long_Integer_Size
- 1),
9508 -- Return True if target supports fixed-by-fixed multiply/divide for
9509 -- fractional fixed-point types (see Is_Fractional_Type) and the operand
9510 -- and result types are equivalent fractional types.
9512 return Is_Fractional_Type
(Base_Type
(Left_Typ
))
9513 and then Is_Fractional_Type
(Base_Type
(Right_Typ
))
9514 and then Is_Fractional_Type
(Base_Type
(Result_Typ
))
9515 and then Esize
(Left_Typ
) = Esize
(Right_Typ
)
9516 and then Esize
(Left_Typ
) = Esize
(Result_Typ
);
9517 end Target_Has_Fixed_Ops
;
9519 ------------------------------------------
9520 -- Type_May_Have_Bit_Aligned_Components --
9521 ------------------------------------------
9523 function Type_May_Have_Bit_Aligned_Components
9524 (Typ
: Entity_Id
) return Boolean
9527 -- Array type, check component type
9529 if Is_Array_Type
(Typ
) then
9531 Type_May_Have_Bit_Aligned_Components
(Component_Type
(Typ
));
9533 -- Record type, check components
9535 elsif Is_Record_Type
(Typ
) then
9540 E
:= First_Component_Or_Discriminant
(Typ
);
9541 while Present
(E
) loop
9542 if Component_May_Be_Bit_Aligned
(E
)
9543 or else Type_May_Have_Bit_Aligned_Components
(Etype
(E
))
9548 Next_Component_Or_Discriminant
(E
);
9554 -- Type other than array or record is always OK
9559 end Type_May_Have_Bit_Aligned_Components
;
9561 ----------------------------------
9562 -- Within_Case_Or_If_Expression --
9563 ----------------------------------
9565 function Within_Case_Or_If_Expression
(N
: Node_Id
) return Boolean is
9569 -- Locate an enclosing case or if expression. Note that these constructs
9570 -- can be expanded into Expression_With_Actions, hence the test of the
9574 while Present
(Par
) loop
9575 if Nkind_In
(Original_Node
(Par
), N_Case_Expression
,
9580 -- Prevent the search from going too far
9582 elsif Is_Body_Or_Package_Declaration
(Par
) then
9586 Par
:= Parent
(Par
);
9590 end Within_Case_Or_If_Expression
;
9592 --------------------------------
9593 -- Within_Internal_Subprogram --
9594 --------------------------------
9596 function Within_Internal_Subprogram
return Boolean is
9601 while Present
(S
) and then not Is_Subprogram
(S
) loop
9606 and then Get_TSS_Name
(S
) /= TSS_Null
9607 and then not Is_Predicate_Function
(S
)
9608 and then not Is_Predicate_Function_M
(S
);
9609 end Within_Internal_Subprogram
;