1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, 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_Eval
; use Sem_Eval
;
50 with Sem_Res
; use Sem_Res
;
51 with Sem_Type
; use Sem_Type
;
52 with Sem_Util
; use Sem_Util
;
53 with Snames
; use Snames
;
54 with Stand
; use Stand
;
55 with Stringt
; use Stringt
;
56 with Targparm
; use Targparm
;
57 with Tbuild
; use Tbuild
;
58 with Ttypes
; use Ttypes
;
59 with Urealp
; use Urealp
;
60 with Validsw
; use Validsw
;
62 package body Exp_Util
is
64 -----------------------
65 -- Local Subprograms --
66 -----------------------
68 function Build_Task_Array_Image
72 Dyn
: Boolean := False) return Node_Id
;
73 -- Build function to generate the image string for a task that is an array
74 -- component, concatenating the images of each index. To avoid storage
75 -- leaks, the string is built with successive slice assignments. The flag
76 -- Dyn indicates whether this is called for the initialization procedure of
77 -- an array of tasks, or for the name of a dynamically created task that is
78 -- assigned to an indexed component.
80 function Build_Task_Image_Function
84 Res
: Entity_Id
) return Node_Id
;
85 -- Common processing for Task_Array_Image and Task_Record_Image. Build
86 -- function body that computes image.
88 procedure Build_Task_Image_Prefix
97 -- Common processing for Task_Array_Image and Task_Record_Image. Create
98 -- local variables and assign prefix of name to result string.
100 function Build_Task_Record_Image
103 Dyn
: Boolean := False) return Node_Id
;
104 -- Build function to generate the image string for a task that is a record
105 -- component. Concatenate name of variable with that of selector. The flag
106 -- Dyn indicates whether this is called for the initialization procedure of
107 -- record with task components, or for a dynamically created task that is
108 -- assigned to a selected component.
110 procedure Evaluate_Slice_Bounds
(Slice
: Node_Id
);
111 -- Force evaluation of bounds of a slice, which may be given by a range
112 -- or by a subtype indication with or without a constraint.
114 function Make_CW_Equivalent_Type
116 E
: Node_Id
) return Entity_Id
;
117 -- T is a class-wide type entity, E is the initial expression node that
118 -- constrains T in case such as: " X: T := E" or "new T'(E)". This function
119 -- returns the entity of the Equivalent type and inserts on the fly the
120 -- necessary declaration such as:
122 -- type anon is record
123 -- _parent : Root_Type (T); constrained with E discriminants (if any)
124 -- Extension : String (1 .. expr to match size of E);
127 -- This record is compatible with any object of the class of T thanks to
128 -- the first field and has the same size as E thanks to the second.
130 function Make_Literal_Range
132 Literal_Typ
: Entity_Id
) return Node_Id
;
133 -- Produce a Range node whose bounds are:
134 -- Low_Bound (Literal_Type) ..
135 -- Low_Bound (Literal_Type) + (Length (Literal_Typ) - 1)
136 -- this is used for expanding declarations like X : String := "sdfgdfg";
138 -- If the index type of the target array is not integer, we generate:
139 -- Low_Bound (Literal_Type) ..
141 -- (Literal_Type'Pos (Low_Bound (Literal_Type))
142 -- + (Length (Literal_Typ) -1))
144 function Make_Non_Empty_Check
146 N
: Node_Id
) return Node_Id
;
147 -- Produce a boolean expression checking that the unidimensional array
148 -- node N is not empty.
150 function New_Class_Wide_Subtype
152 N
: Node_Id
) return Entity_Id
;
153 -- Create an implicit subtype of CW_Typ attached to node N
155 function Requires_Cleanup_Actions
158 Nested_Constructs
: Boolean) return Boolean;
159 -- Given a list L, determine whether it contains one of the following:
161 -- 1) controlled objects
162 -- 2) library-level tagged types
164 -- Lib_Level is True when the list comes from a construct at the library
165 -- level, and False otherwise. Nested_Constructs is True when any nested
166 -- packages declared in L must be processed, and False otherwise.
168 -------------------------------------
169 -- Activate_Atomic_Synchronization --
170 -------------------------------------
172 procedure Activate_Atomic_Synchronization
(N
: Node_Id
) is
176 case Nkind
(Parent
(N
)) is
178 -- Check for cases of appearing in the prefix of a construct where
179 -- we don't need atomic synchronization for this kind of usage.
182 -- Nothing to do if we are the prefix of an attribute, since we
183 -- do not want an atomic sync operation for things like 'Size.
185 N_Attribute_Reference |
187 -- The N_Reference node is like an attribute
191 -- Nothing to do for a reference to a component (or components)
192 -- of a composite object. Only reads and updates of the object
193 -- as a whole require atomic synchronization (RM C.6 (15)).
195 N_Indexed_Component |
196 N_Selected_Component |
199 -- For all the above cases, nothing to do if we are the prefix
201 if Prefix
(Parent
(N
)) = N
then
208 -- Nothing to do for the identifier in an object renaming declaration,
209 -- the renaming itself does not need atomic synchronization.
211 if Nkind
(Parent
(N
)) = N_Object_Renaming_Declaration
then
215 -- Go ahead and set the flag
217 Set_Atomic_Sync_Required
(N
);
219 -- Generate info message if requested
221 if Warn_On_Atomic_Synchronization
then
226 when N_Selected_Component | N_Expanded_Name
=>
227 Msg_Node
:= Selector_Name
(N
);
229 when N_Explicit_Dereference | N_Indexed_Component
=>
233 pragma Assert
(False);
237 if Present
(Msg_Node
) then
239 ("info: atomic synchronization set for &?N?", Msg_Node
);
242 ("info: atomic synchronization set?N?", N
);
245 end Activate_Atomic_Synchronization
;
247 ----------------------
248 -- Adjust_Condition --
249 ----------------------
251 procedure Adjust_Condition
(N
: Node_Id
) is
258 Loc
: constant Source_Ptr
:= Sloc
(N
);
259 T
: constant Entity_Id
:= Etype
(N
);
263 -- Defend against a call where the argument has no type, or has a
264 -- type that is not Boolean. This can occur because of prior errors.
266 if No
(T
) or else not Is_Boolean_Type
(T
) then
270 -- Apply validity checking if needed
272 if Validity_Checks_On
and Validity_Check_Tests
then
276 -- Immediate return if standard boolean, the most common case,
277 -- where nothing needs to be done.
279 if Base_Type
(T
) = Standard_Boolean
then
283 -- Case of zero/non-zero semantics or non-standard enumeration
284 -- representation. In each case, we rewrite the node as:
286 -- ityp!(N) /= False'Enum_Rep
288 -- where ityp is an integer type with large enough size to hold any
291 if Nonzero_Is_True
(T
) or else Has_Non_Standard_Rep
(T
) then
292 if Esize
(T
) <= Esize
(Standard_Integer
) then
293 Ti
:= Standard_Integer
;
295 Ti
:= Standard_Long_Long_Integer
;
300 Left_Opnd
=> Unchecked_Convert_To
(Ti
, N
),
302 Make_Attribute_Reference
(Loc
,
303 Attribute_Name
=> Name_Enum_Rep
,
305 New_Occurrence_Of
(First_Literal
(T
), Loc
))));
306 Analyze_And_Resolve
(N
, Standard_Boolean
);
309 Rewrite
(N
, Convert_To
(Standard_Boolean
, N
));
310 Analyze_And_Resolve
(N
, Standard_Boolean
);
313 end Adjust_Condition
;
315 ------------------------
316 -- Adjust_Result_Type --
317 ------------------------
319 procedure Adjust_Result_Type
(N
: Node_Id
; T
: Entity_Id
) is
321 -- Ignore call if current type is not Standard.Boolean
323 if Etype
(N
) /= Standard_Boolean
then
327 -- If result is already of correct type, nothing to do. Note that
328 -- this will get the most common case where everything has a type
329 -- of Standard.Boolean.
331 if Base_Type
(T
) = Standard_Boolean
then
336 KP
: constant Node_Kind
:= Nkind
(Parent
(N
));
339 -- If result is to be used as a Condition in the syntax, no need
340 -- to convert it back, since if it was changed to Standard.Boolean
341 -- using Adjust_Condition, that is just fine for this usage.
343 if KP
in N_Raise_xxx_Error
or else KP
in N_Has_Condition
then
346 -- If result is an operand of another logical operation, no need
347 -- to reset its type, since Standard.Boolean is just fine, and
348 -- such operations always do Adjust_Condition on their operands.
350 elsif KP
in N_Op_Boolean
351 or else KP
in N_Short_Circuit
352 or else KP
= N_Op_Not
356 -- Otherwise we perform a conversion from the current type, which
357 -- must be Standard.Boolean, to the desired type.
361 Rewrite
(N
, Convert_To
(T
, N
));
362 Analyze_And_Resolve
(N
, T
);
366 end Adjust_Result_Type
;
368 --------------------------
369 -- Append_Freeze_Action --
370 --------------------------
372 procedure Append_Freeze_Action
(T
: Entity_Id
; N
: Node_Id
) is
376 Ensure_Freeze_Node
(T
);
377 Fnode
:= Freeze_Node
(T
);
379 if No
(Actions
(Fnode
)) then
380 Set_Actions
(Fnode
, New_List
(N
));
382 Append
(N
, Actions
(Fnode
));
385 end Append_Freeze_Action
;
387 ---------------------------
388 -- Append_Freeze_Actions --
389 ---------------------------
391 procedure Append_Freeze_Actions
(T
: Entity_Id
; L
: List_Id
) is
399 Ensure_Freeze_Node
(T
);
400 Fnode
:= Freeze_Node
(T
);
402 if No
(Actions
(Fnode
)) then
403 Set_Actions
(Fnode
, L
);
405 Append_List
(L
, Actions
(Fnode
));
407 end Append_Freeze_Actions
;
409 ------------------------------------
410 -- Build_Allocate_Deallocate_Proc --
411 ------------------------------------
413 procedure Build_Allocate_Deallocate_Proc
415 Is_Allocate
: Boolean)
417 Desig_Typ
: Entity_Id
;
420 Proc_To_Call
: Node_Id
:= Empty
;
423 function Find_Object
(E
: Node_Id
) return Node_Id
;
424 -- Given an arbitrary expression of an allocator, try to find an object
425 -- reference in it, otherwise return the original expression.
427 function Is_Allocate_Deallocate_Proc
(Subp
: Entity_Id
) return Boolean;
428 -- Determine whether subprogram Subp denotes a custom allocate or
435 function Find_Object
(E
: Node_Id
) return Node_Id
is
439 pragma Assert
(Is_Allocate
);
443 if Nkind
(Expr
) = N_Explicit_Dereference
then
444 Expr
:= Prefix
(Expr
);
446 elsif Nkind
(Expr
) = N_Qualified_Expression
then
447 Expr
:= Expression
(Expr
);
449 elsif Nkind
(Expr
) = N_Unchecked_Type_Conversion
then
451 -- When interface class-wide types are involved in allocation,
452 -- the expander introduces several levels of address arithmetic
453 -- to perform dispatch table displacement. In this scenario the
454 -- object appears as:
456 -- Tag_Ptr (Base_Address (<object>'Address))
458 -- Detect this case and utilize the whole expression as the
459 -- "object" since it now points to the proper dispatch table.
461 if Is_RTE
(Etype
(Expr
), RE_Tag_Ptr
) then
464 -- Continue to strip the object
467 Expr
:= Expression
(Expr
);
478 ---------------------------------
479 -- Is_Allocate_Deallocate_Proc --
480 ---------------------------------
482 function Is_Allocate_Deallocate_Proc
(Subp
: Entity_Id
) return Boolean is
484 -- Look for a subprogram body with only one statement which is a
485 -- call to Allocate_Any_Controlled / Deallocate_Any_Controlled.
487 if Ekind
(Subp
) = E_Procedure
488 and then Nkind
(Parent
(Parent
(Subp
))) = N_Subprogram_Body
491 HSS
: constant Node_Id
:=
492 Handled_Statement_Sequence
(Parent
(Parent
(Subp
)));
496 if Present
(Statements
(HSS
))
497 and then Nkind
(First
(Statements
(HSS
))) =
498 N_Procedure_Call_Statement
500 Proc
:= Entity
(Name
(First
(Statements
(HSS
))));
503 Is_RTE
(Proc
, RE_Allocate_Any_Controlled
)
504 or else Is_RTE
(Proc
, RE_Deallocate_Any_Controlled
);
510 end Is_Allocate_Deallocate_Proc
;
512 -- Start of processing for Build_Allocate_Deallocate_Proc
515 -- Obtain the attributes of the allocation / deallocation
517 if Nkind
(N
) = N_Free_Statement
then
518 Expr
:= Expression
(N
);
519 Ptr_Typ
:= Base_Type
(Etype
(Expr
));
520 Proc_To_Call
:= Procedure_To_Call
(N
);
523 if Nkind
(N
) = N_Object_Declaration
then
524 Expr
:= Expression
(N
);
529 -- In certain cases an allocator with a qualified expression may
530 -- be relocated and used as the initialization expression of a
534 -- Obj : Ptr_Typ := new Desig_Typ'(...);
537 -- Tmp : Ptr_Typ := new Desig_Typ'(...);
538 -- Obj : Ptr_Typ := Tmp;
540 -- Since the allocator is always marked as analyzed to avoid infinite
541 -- expansion, it will never be processed by this routine given that
542 -- the designated type needs finalization actions. Detect this case
543 -- and complete the expansion of the allocator.
545 if Nkind
(Expr
) = N_Identifier
546 and then Nkind
(Parent
(Entity
(Expr
))) = N_Object_Declaration
547 and then Nkind
(Expression
(Parent
(Entity
(Expr
)))) = N_Allocator
549 Build_Allocate_Deallocate_Proc
(Parent
(Entity
(Expr
)), True);
553 -- The allocator may have been rewritten into something else in which
554 -- case the expansion performed by this routine does not apply.
556 if Nkind
(Expr
) /= N_Allocator
then
560 Ptr_Typ
:= Base_Type
(Etype
(Expr
));
561 Proc_To_Call
:= Procedure_To_Call
(Expr
);
564 Pool_Id
:= Associated_Storage_Pool
(Ptr_Typ
);
565 Desig_Typ
:= Available_View
(Designated_Type
(Ptr_Typ
));
567 -- Handle concurrent types
569 if Is_Concurrent_Type
(Desig_Typ
)
570 and then Present
(Corresponding_Record_Type
(Desig_Typ
))
572 Desig_Typ
:= Corresponding_Record_Type
(Desig_Typ
);
575 -- Do not process allocations / deallocations without a pool
580 -- Do not process allocations on / deallocations from the secondary
583 elsif Is_RTE
(Pool_Id
, RE_SS_Pool
) then
586 -- Do not replicate the machinery if the allocator / free has already
587 -- been expanded and has a custom Allocate / Deallocate.
589 elsif Present
(Proc_To_Call
)
590 and then Is_Allocate_Deallocate_Proc
(Proc_To_Call
)
595 if Needs_Finalization
(Desig_Typ
) then
597 -- Certain run-time configurations and targets do not provide support
598 -- for controlled types.
600 if Restriction_Active
(No_Finalization
) then
603 -- Do nothing if the access type may never allocate / deallocate
606 elsif No_Pool_Assigned
(Ptr_Typ
) then
610 -- The allocation / deallocation of a controlled object must be
611 -- chained on / detached from a finalization master.
613 pragma Assert
(Present
(Finalization_Master
(Ptr_Typ
)));
615 -- The only other kind of allocation / deallocation supported by this
616 -- routine is on / from a subpool.
618 elsif Nkind
(Expr
) = N_Allocator
619 and then No
(Subpool_Handle_Name
(Expr
))
625 Loc
: constant Source_Ptr
:= Sloc
(N
);
626 Addr_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
627 Alig_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'L');
628 Proc_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'P');
629 Size_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'S');
632 Fin_Addr_Id
: Entity_Id
;
633 Fin_Mas_Act
: Node_Id
;
634 Fin_Mas_Id
: Entity_Id
;
635 Proc_To_Call
: Entity_Id
;
636 Subpool
: Node_Id
:= Empty
;
639 -- Step 1: Construct all the actuals for the call to library routine
640 -- Allocate_Any_Controlled / Deallocate_Any_Controlled.
644 Actuals
:= New_List
(New_Occurrence_Of
(Pool_Id
, Loc
));
650 if Nkind
(Expr
) = N_Allocator
then
651 Subpool
:= Subpool_Handle_Name
(Expr
);
654 -- If a subpool is present it can be an arbitrary name, so make
655 -- the actual by copying the tree.
657 if Present
(Subpool
) then
658 Append_To
(Actuals
, New_Copy_Tree
(Subpool
, New_Sloc
=> Loc
));
660 Append_To
(Actuals
, Make_Null
(Loc
));
663 -- c) Finalization master
665 if Needs_Finalization
(Desig_Typ
) then
666 Fin_Mas_Id
:= Finalization_Master
(Ptr_Typ
);
667 Fin_Mas_Act
:= New_Occurrence_Of
(Fin_Mas_Id
, Loc
);
669 -- Handle the case where the master is actually a pointer to a
670 -- master. This case arises in build-in-place functions.
672 if Is_Access_Type
(Etype
(Fin_Mas_Id
)) then
673 Append_To
(Actuals
, Fin_Mas_Act
);
676 Make_Attribute_Reference
(Loc
,
677 Prefix
=> Fin_Mas_Act
,
678 Attribute_Name
=> Name_Unrestricted_Access
));
681 Append_To
(Actuals
, Make_Null
(Loc
));
684 -- d) Finalize_Address
686 -- Primitive Finalize_Address is never generated in CodePeer mode
687 -- since it contains an Unchecked_Conversion.
689 if Needs_Finalization
(Desig_Typ
) and then not CodePeer_Mode
then
690 Fin_Addr_Id
:= Finalize_Address
(Desig_Typ
);
691 pragma Assert
(Present
(Fin_Addr_Id
));
694 Make_Attribute_Reference
(Loc
,
695 Prefix
=> New_Occurrence_Of
(Fin_Addr_Id
, Loc
),
696 Attribute_Name
=> Name_Unrestricted_Access
));
698 Append_To
(Actuals
, Make_Null
(Loc
));
706 Append_To
(Actuals
, New_Occurrence_Of
(Addr_Id
, Loc
));
707 Append_To
(Actuals
, New_Occurrence_Of
(Size_Id
, Loc
));
709 if Is_Allocate
or else not Is_Class_Wide_Type
(Desig_Typ
) then
710 Append_To
(Actuals
, New_Occurrence_Of
(Alig_Id
, Loc
));
712 -- For deallocation of class-wide types we obtain the value of
713 -- alignment from the Type Specific Record of the deallocated object.
714 -- This is needed because the frontend expansion of class-wide types
715 -- into equivalent types confuses the backend.
721 -- ... because 'Alignment applied to class-wide types is expanded
722 -- into the code that reads the value of alignment from the TSD
723 -- (see Expand_N_Attribute_Reference)
726 Unchecked_Convert_To
(RTE
(RE_Storage_Offset
),
727 Make_Attribute_Reference
(Loc
,
729 Make_Explicit_Dereference
(Loc
, Relocate_Node
(Expr
)),
730 Attribute_Name
=> Name_Alignment
)));
735 if Needs_Finalization
(Desig_Typ
) then
737 Flag_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'F');
744 Temp
:= Find_Object
(Expression
(Expr
));
749 -- Processing for allocations where the expression is a subtype
753 and then Is_Entity_Name
(Temp
)
754 and then Is_Type
(Entity
(Temp
))
759 (Needs_Finalization
(Entity
(Temp
))), Loc
);
761 -- The allocation / deallocation of a class-wide object relies
762 -- on a runtime check to determine whether the object is truly
763 -- controlled or not. Depending on this check, the finalization
764 -- machinery will request or reclaim extra storage reserved for
767 elsif Is_Class_Wide_Type
(Desig_Typ
) then
769 -- Detect a special case where interface class-wide types
770 -- are involved as the object appears as:
772 -- Tag_Ptr (Base_Address (<object>'Address))
774 -- The expression already yields the proper tag, generate:
778 if Is_RTE
(Etype
(Temp
), RE_Tag_Ptr
) then
780 Make_Explicit_Dereference
(Loc
,
781 Prefix
=> Relocate_Node
(Temp
));
783 -- In the default case, obtain the tag of the object about
784 -- to be allocated / deallocated. Generate:
790 Make_Attribute_Reference
(Loc
,
791 Prefix
=> Relocate_Node
(Temp
),
792 Attribute_Name
=> Name_Tag
);
796 -- Needs_Finalization (<Param>)
799 Make_Function_Call
(Loc
,
801 New_Occurrence_Of
(RTE
(RE_Needs_Finalization
), Loc
),
802 Parameter_Associations
=> New_List
(Param
));
804 -- Processing for generic actuals
806 elsif Is_Generic_Actual_Type
(Desig_Typ
) then
808 New_Occurrence_Of
(Boolean_Literals
809 (Needs_Finalization
(Base_Type
(Desig_Typ
))), Loc
);
811 -- The object does not require any specialized checks, it is
812 -- known to be controlled.
815 Flag_Expr
:= New_Occurrence_Of
(Standard_True
, Loc
);
818 -- Create the temporary which represents the finalization state
819 -- of the expression. Generate:
821 -- F : constant Boolean := <Flag_Expr>;
824 Make_Object_Declaration
(Loc
,
825 Defining_Identifier
=> Flag_Id
,
826 Constant_Present
=> True,
828 New_Occurrence_Of
(Standard_Boolean
, Loc
),
829 Expression
=> Flag_Expr
));
831 Append_To
(Actuals
, New_Occurrence_Of
(Flag_Id
, Loc
));
834 -- The object is not controlled
837 Append_To
(Actuals
, New_Occurrence_Of
(Standard_False
, Loc
));
844 New_Occurrence_Of
(Boolean_Literals
(Present
(Subpool
)), Loc
));
847 -- Step 2: Build a wrapper Allocate / Deallocate which internally
848 -- calls Allocate_Any_Controlled / Deallocate_Any_Controlled.
850 -- Select the proper routine to call
853 Proc_To_Call
:= RTE
(RE_Allocate_Any_Controlled
);
855 Proc_To_Call
:= RTE
(RE_Deallocate_Any_Controlled
);
858 -- Create a custom Allocate / Deallocate routine which has identical
859 -- profile to that of System.Storage_Pools.
862 Make_Subprogram_Body
(Loc
,
867 Make_Procedure_Specification
(Loc
,
868 Defining_Unit_Name
=> Proc_Id
,
869 Parameter_Specifications
=> New_List
(
871 -- P : Root_Storage_Pool
873 Make_Parameter_Specification
(Loc
,
874 Defining_Identifier
=> Make_Temporary
(Loc
, 'P'),
876 New_Occurrence_Of
(RTE
(RE_Root_Storage_Pool
), Loc
)),
880 Make_Parameter_Specification
(Loc
,
881 Defining_Identifier
=> Addr_Id
,
882 Out_Present
=> Is_Allocate
,
884 New_Occurrence_Of
(RTE
(RE_Address
), Loc
)),
888 Make_Parameter_Specification
(Loc
,
889 Defining_Identifier
=> Size_Id
,
891 New_Occurrence_Of
(RTE
(RE_Storage_Count
), Loc
)),
895 Make_Parameter_Specification
(Loc
,
896 Defining_Identifier
=> Alig_Id
,
898 New_Occurrence_Of
(RTE
(RE_Storage_Count
), Loc
)))),
900 Declarations
=> No_List
,
902 Handled_Statement_Sequence
=>
903 Make_Handled_Sequence_Of_Statements
(Loc
,
904 Statements
=> New_List
(
905 Make_Procedure_Call_Statement
(Loc
,
906 Name
=> New_Occurrence_Of
(Proc_To_Call
, Loc
),
907 Parameter_Associations
=> Actuals
)))));
909 -- The newly generated Allocate / Deallocate becomes the default
910 -- procedure to call when the back end processes the allocation /
914 Set_Procedure_To_Call
(Expr
, Proc_Id
);
916 Set_Procedure_To_Call
(N
, Proc_Id
);
919 end Build_Allocate_Deallocate_Proc
;
921 ------------------------
922 -- Build_Runtime_Call --
923 ------------------------
925 function Build_Runtime_Call
(Loc
: Source_Ptr
; RE
: RE_Id
) return Node_Id
is
927 -- If entity is not available, we can skip making the call (this avoids
928 -- junk duplicated error messages in a number of cases).
930 if not RTE_Available
(RE
) then
931 return Make_Null_Statement
(Loc
);
934 Make_Procedure_Call_Statement
(Loc
,
935 Name
=> New_Occurrence_Of
(RTE
(RE
), Loc
));
937 end Build_Runtime_Call
;
939 ------------------------
940 -- Build_SS_Mark_Call --
941 ------------------------
943 function Build_SS_Mark_Call
945 Mark
: Entity_Id
) return Node_Id
949 -- Mark : constant Mark_Id := SS_Mark;
952 Make_Object_Declaration
(Loc
,
953 Defining_Identifier
=> Mark
,
954 Constant_Present
=> True,
956 New_Occurrence_Of
(RTE
(RE_Mark_Id
), Loc
),
958 Make_Function_Call
(Loc
,
959 Name
=> New_Occurrence_Of
(RTE
(RE_SS_Mark
), Loc
)));
960 end Build_SS_Mark_Call
;
962 ---------------------------
963 -- Build_SS_Release_Call --
964 ---------------------------
966 function Build_SS_Release_Call
968 Mark
: Entity_Id
) return Node_Id
972 -- SS_Release (Mark);
975 Make_Procedure_Call_Statement
(Loc
,
977 New_Occurrence_Of
(RTE
(RE_SS_Release
), Loc
),
978 Parameter_Associations
=> New_List
(
979 New_Occurrence_Of
(Mark
, Loc
)));
980 end Build_SS_Release_Call
;
982 ----------------------------
983 -- Build_Task_Array_Image --
984 ----------------------------
986 -- This function generates the body for a function that constructs the
987 -- image string for a task that is an array component. The function is
988 -- local to the init proc for the array type, and is called for each one
989 -- of the components. The constructed image has the form of an indexed
990 -- component, whose prefix is the outer variable of the array type.
991 -- The n-dimensional array type has known indexes Index, Index2...
993 -- Id_Ref is an indexed component form created by the enclosing init proc.
994 -- Its successive indexes are Val1, Val2, ... which are the loop variables
995 -- in the loops that call the individual task init proc on each component.
997 -- The generated function has the following structure:
999 -- function F return String is
1000 -- Pref : string renames Task_Name;
1001 -- T1 : String := Index1'Image (Val1);
1003 -- Tn : String := indexn'image (Valn);
1004 -- Len : Integer := T1'Length + ... + Tn'Length + n + 1;
1005 -- -- Len includes commas and the end parentheses.
1006 -- Res : String (1..Len);
1007 -- Pos : Integer := Pref'Length;
1010 -- Res (1 .. Pos) := Pref;
1012 -- Res (Pos) := '(';
1014 -- Res (Pos .. Pos + T1'Length - 1) := T1;
1015 -- Pos := Pos + T1'Length;
1016 -- Res (Pos) := '.';
1019 -- Res (Pos .. Pos + Tn'Length - 1) := Tn;
1020 -- Res (Len) := ')';
1025 -- Needless to say, multidimensional arrays of tasks are rare enough that
1026 -- the bulkiness of this code is not really a concern.
1028 function Build_Task_Array_Image
1032 Dyn
: Boolean := False) return Node_Id
1034 Dims
: constant Nat
:= Number_Dimensions
(A_Type
);
1035 -- Number of dimensions for array of tasks
1037 Temps
: array (1 .. Dims
) of Entity_Id
;
1038 -- Array of temporaries to hold string for each index
1044 -- Total length of generated name
1047 -- Running index for substring assignments
1049 Pref
: constant Entity_Id
:= Make_Temporary
(Loc
, 'P');
1050 -- Name of enclosing variable, prefix of resulting name
1053 -- String to hold result
1056 -- Value of successive indexes
1059 -- Expression to compute total size of string
1062 -- Entity for name at one index position
1064 Decls
: constant List_Id
:= New_List
;
1065 Stats
: constant List_Id
:= New_List
;
1068 -- For a dynamic task, the name comes from the target variable. For a
1069 -- static one it is a formal of the enclosing init proc.
1072 Get_Name_String
(Chars
(Entity
(Prefix
(Id_Ref
))));
1074 Make_Object_Declaration
(Loc
,
1075 Defining_Identifier
=> Pref
,
1076 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1078 Make_String_Literal
(Loc
,
1079 Strval
=> String_From_Name_Buffer
)));
1083 Make_Object_Renaming_Declaration
(Loc
,
1084 Defining_Identifier
=> Pref
,
1085 Subtype_Mark
=> New_Occurrence_Of
(Standard_String
, Loc
),
1086 Name
=> Make_Identifier
(Loc
, Name_uTask_Name
)));
1089 Indx
:= First_Index
(A_Type
);
1090 Val
:= First
(Expressions
(Id_Ref
));
1092 for J
in 1 .. Dims
loop
1093 T
:= Make_Temporary
(Loc
, 'T');
1097 Make_Object_Declaration
(Loc
,
1098 Defining_Identifier
=> T
,
1099 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1101 Make_Attribute_Reference
(Loc
,
1102 Attribute_Name
=> Name_Image
,
1103 Prefix
=> New_Occurrence_Of
(Etype
(Indx
), Loc
),
1104 Expressions
=> New_List
(New_Copy_Tree
(Val
)))));
1110 Sum
:= Make_Integer_Literal
(Loc
, Dims
+ 1);
1116 Make_Attribute_Reference
(Loc
,
1117 Attribute_Name
=> Name_Length
,
1118 Prefix
=> New_Occurrence_Of
(Pref
, Loc
),
1119 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1))));
1121 for J
in 1 .. Dims
loop
1126 Make_Attribute_Reference
(Loc
,
1127 Attribute_Name
=> Name_Length
,
1129 New_Occurrence_Of
(Temps
(J
), Loc
),
1130 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1))));
1133 Build_Task_Image_Prefix
(Loc
, Len
, Res
, Pos
, Pref
, Sum
, Decls
, Stats
);
1135 Set_Character_Literal_Name
(Char_Code
(Character'Pos ('(')));
1138 Make_Assignment_Statement
(Loc
,
1140 Make_Indexed_Component
(Loc
,
1141 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1142 Expressions
=> New_List
(New_Occurrence_Of
(Pos
, Loc
))),
1144 Make_Character_Literal
(Loc
,
1146 Char_Literal_Value
=> UI_From_Int
(Character'Pos ('(')))));
1149 Make_Assignment_Statement
(Loc
,
1150 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1153 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1154 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1156 for J
in 1 .. Dims
loop
1159 Make_Assignment_Statement
(Loc
,
1162 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1165 Low_Bound
=> New_Occurrence_Of
(Pos
, Loc
),
1167 Make_Op_Subtract
(Loc
,
1170 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1172 Make_Attribute_Reference
(Loc
,
1173 Attribute_Name
=> Name_Length
,
1175 New_Occurrence_Of
(Temps
(J
), Loc
),
1177 New_List
(Make_Integer_Literal
(Loc
, 1)))),
1178 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1)))),
1180 Expression
=> New_Occurrence_Of
(Temps
(J
), Loc
)));
1184 Make_Assignment_Statement
(Loc
,
1185 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1188 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1190 Make_Attribute_Reference
(Loc
,
1191 Attribute_Name
=> Name_Length
,
1192 Prefix
=> New_Occurrence_Of
(Temps
(J
), Loc
),
1194 New_List
(Make_Integer_Literal
(Loc
, 1))))));
1196 Set_Character_Literal_Name
(Char_Code
(Character'Pos (',')));
1199 Make_Assignment_Statement
(Loc
,
1200 Name
=> Make_Indexed_Component
(Loc
,
1201 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1202 Expressions
=> New_List
(New_Occurrence_Of
(Pos
, Loc
))),
1204 Make_Character_Literal
(Loc
,
1206 Char_Literal_Value
=> UI_From_Int
(Character'Pos (',')))));
1209 Make_Assignment_Statement
(Loc
,
1210 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1213 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1214 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1218 Set_Character_Literal_Name
(Char_Code
(Character'Pos (')')));
1221 Make_Assignment_Statement
(Loc
,
1223 Make_Indexed_Component
(Loc
,
1224 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1225 Expressions
=> New_List
(New_Occurrence_Of
(Len
, Loc
))),
1227 Make_Character_Literal
(Loc
,
1229 Char_Literal_Value
=> UI_From_Int
(Character'Pos (')')))));
1230 return Build_Task_Image_Function
(Loc
, Decls
, Stats
, Res
);
1231 end Build_Task_Array_Image
;
1233 ----------------------------
1234 -- Build_Task_Image_Decls --
1235 ----------------------------
1237 function Build_Task_Image_Decls
1241 In_Init_Proc
: Boolean := False) return List_Id
1243 Decls
: constant List_Id
:= New_List
;
1244 T_Id
: Entity_Id
:= Empty
;
1246 Expr
: Node_Id
:= Empty
;
1247 Fun
: Node_Id
:= Empty
;
1248 Is_Dyn
: constant Boolean :=
1249 Nkind
(Parent
(Id_Ref
)) = N_Assignment_Statement
1251 Nkind
(Expression
(Parent
(Id_Ref
))) = N_Allocator
;
1254 -- If Discard_Names or No_Implicit_Heap_Allocations are in effect,
1255 -- generate a dummy declaration only.
1257 if Restriction_Active
(No_Implicit_Heap_Allocations
)
1258 or else Global_Discard_Names
1260 T_Id
:= Make_Temporary
(Loc
, 'J');
1265 Make_Object_Declaration
(Loc
,
1266 Defining_Identifier
=> T_Id
,
1267 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1269 Make_String_Literal
(Loc
,
1270 Strval
=> String_From_Name_Buffer
)));
1273 if Nkind
(Id_Ref
) = N_Identifier
1274 or else Nkind
(Id_Ref
) = N_Defining_Identifier
1276 -- For a simple variable, the image of the task is built from
1277 -- the name of the variable. To avoid possible conflict with the
1278 -- anonymous type created for a single protected object, add a
1282 Make_Defining_Identifier
(Loc
,
1283 New_External_Name
(Chars
(Id_Ref
), 'T', 1));
1285 Get_Name_String
(Chars
(Id_Ref
));
1288 Make_String_Literal
(Loc
,
1289 Strval
=> String_From_Name_Buffer
);
1291 elsif Nkind
(Id_Ref
) = N_Selected_Component
then
1293 Make_Defining_Identifier
(Loc
,
1294 New_External_Name
(Chars
(Selector_Name
(Id_Ref
)), 'T'));
1295 Fun
:= Build_Task_Record_Image
(Loc
, Id_Ref
, Is_Dyn
);
1297 elsif Nkind
(Id_Ref
) = N_Indexed_Component
then
1299 Make_Defining_Identifier
(Loc
,
1300 New_External_Name
(Chars
(A_Type
), 'N'));
1302 Fun
:= Build_Task_Array_Image
(Loc
, Id_Ref
, A_Type
, Is_Dyn
);
1306 if Present
(Fun
) then
1307 Append
(Fun
, Decls
);
1308 Expr
:= Make_Function_Call
(Loc
,
1309 Name
=> New_Occurrence_Of
(Defining_Entity
(Fun
), Loc
));
1311 if not In_Init_Proc
then
1312 Set_Uses_Sec_Stack
(Defining_Entity
(Fun
));
1316 Decl
:= Make_Object_Declaration
(Loc
,
1317 Defining_Identifier
=> T_Id
,
1318 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1319 Constant_Present
=> True,
1320 Expression
=> Expr
);
1322 Append
(Decl
, Decls
);
1324 end Build_Task_Image_Decls
;
1326 -------------------------------
1327 -- Build_Task_Image_Function --
1328 -------------------------------
1330 function Build_Task_Image_Function
1334 Res
: Entity_Id
) return Node_Id
1340 Make_Simple_Return_Statement
(Loc
,
1341 Expression
=> New_Occurrence_Of
(Res
, Loc
)));
1343 Spec
:= Make_Function_Specification
(Loc
,
1344 Defining_Unit_Name
=> Make_Temporary
(Loc
, 'F'),
1345 Result_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
));
1347 -- Calls to 'Image use the secondary stack, which must be cleaned up
1348 -- after the task name is built.
1350 return Make_Subprogram_Body
(Loc
,
1351 Specification
=> Spec
,
1352 Declarations
=> Decls
,
1353 Handled_Statement_Sequence
=>
1354 Make_Handled_Sequence_Of_Statements
(Loc
, Statements
=> Stats
));
1355 end Build_Task_Image_Function
;
1357 -----------------------------
1358 -- Build_Task_Image_Prefix --
1359 -----------------------------
1361 procedure Build_Task_Image_Prefix
1363 Len
: out Entity_Id
;
1364 Res
: out Entity_Id
;
1365 Pos
: out Entity_Id
;
1372 Len
:= Make_Temporary
(Loc
, 'L', Sum
);
1375 Make_Object_Declaration
(Loc
,
1376 Defining_Identifier
=> Len
,
1377 Object_Definition
=> New_Occurrence_Of
(Standard_Integer
, Loc
),
1378 Expression
=> Sum
));
1380 Res
:= Make_Temporary
(Loc
, 'R');
1383 Make_Object_Declaration
(Loc
,
1384 Defining_Identifier
=> Res
,
1385 Object_Definition
=>
1386 Make_Subtype_Indication
(Loc
,
1387 Subtype_Mark
=> New_Occurrence_Of
(Standard_String
, Loc
),
1389 Make_Index_Or_Discriminant_Constraint
(Loc
,
1393 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
1394 High_Bound
=> New_Occurrence_Of
(Len
, Loc
)))))));
1396 -- Indicate that the result is an internal temporary, so it does not
1397 -- receive a bogus initialization when declaration is expanded. This
1398 -- is both efficient, and prevents anomalies in the handling of
1399 -- dynamic objects on the secondary stack.
1401 Set_Is_Internal
(Res
);
1402 Pos
:= Make_Temporary
(Loc
, 'P');
1405 Make_Object_Declaration
(Loc
,
1406 Defining_Identifier
=> Pos
,
1407 Object_Definition
=> New_Occurrence_Of
(Standard_Integer
, Loc
)));
1409 -- Pos := Prefix'Length;
1412 Make_Assignment_Statement
(Loc
,
1413 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1415 Make_Attribute_Reference
(Loc
,
1416 Attribute_Name
=> Name_Length
,
1417 Prefix
=> New_Occurrence_Of
(Prefix
, Loc
),
1418 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1)))));
1420 -- Res (1 .. Pos) := Prefix;
1423 Make_Assignment_Statement
(Loc
,
1426 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1429 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
1430 High_Bound
=> New_Occurrence_Of
(Pos
, Loc
))),
1432 Expression
=> New_Occurrence_Of
(Prefix
, Loc
)));
1435 Make_Assignment_Statement
(Loc
,
1436 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1439 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1440 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1441 end Build_Task_Image_Prefix
;
1443 -----------------------------
1444 -- Build_Task_Record_Image --
1445 -----------------------------
1447 function Build_Task_Record_Image
1450 Dyn
: Boolean := False) return Node_Id
1453 -- Total length of generated name
1456 -- Index into result
1459 -- String to hold result
1461 Pref
: constant Entity_Id
:= Make_Temporary
(Loc
, 'P');
1462 -- Name of enclosing variable, prefix of resulting name
1465 -- Expression to compute total size of string
1468 -- Entity for selector name
1470 Decls
: constant List_Id
:= New_List
;
1471 Stats
: constant List_Id
:= New_List
;
1474 -- For a dynamic task, the name comes from the target variable. For a
1475 -- static one it is a formal of the enclosing init proc.
1478 Get_Name_String
(Chars
(Entity
(Prefix
(Id_Ref
))));
1480 Make_Object_Declaration
(Loc
,
1481 Defining_Identifier
=> Pref
,
1482 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1484 Make_String_Literal
(Loc
,
1485 Strval
=> String_From_Name_Buffer
)));
1489 Make_Object_Renaming_Declaration
(Loc
,
1490 Defining_Identifier
=> Pref
,
1491 Subtype_Mark
=> New_Occurrence_Of
(Standard_String
, Loc
),
1492 Name
=> Make_Identifier
(Loc
, Name_uTask_Name
)));
1495 Sel
:= Make_Temporary
(Loc
, 'S');
1497 Get_Name_String
(Chars
(Selector_Name
(Id_Ref
)));
1500 Make_Object_Declaration
(Loc
,
1501 Defining_Identifier
=> Sel
,
1502 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1504 Make_String_Literal
(Loc
,
1505 Strval
=> String_From_Name_Buffer
)));
1507 Sum
:= Make_Integer_Literal
(Loc
, Nat
(Name_Len
+ 1));
1513 Make_Attribute_Reference
(Loc
,
1514 Attribute_Name
=> Name_Length
,
1516 New_Occurrence_Of
(Pref
, Loc
),
1517 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1))));
1519 Build_Task_Image_Prefix
(Loc
, Len
, Res
, Pos
, Pref
, Sum
, Decls
, Stats
);
1521 Set_Character_Literal_Name
(Char_Code
(Character'Pos ('.')));
1523 -- Res (Pos) := '.';
1526 Make_Assignment_Statement
(Loc
,
1527 Name
=> Make_Indexed_Component
(Loc
,
1528 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1529 Expressions
=> New_List
(New_Occurrence_Of
(Pos
, Loc
))),
1531 Make_Character_Literal
(Loc
,
1533 Char_Literal_Value
=>
1534 UI_From_Int
(Character'Pos ('.')))));
1537 Make_Assignment_Statement
(Loc
,
1538 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1541 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1542 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1544 -- Res (Pos .. Len) := Selector;
1547 Make_Assignment_Statement
(Loc
,
1548 Name
=> Make_Slice
(Loc
,
1549 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1552 Low_Bound
=> New_Occurrence_Of
(Pos
, Loc
),
1553 High_Bound
=> New_Occurrence_Of
(Len
, Loc
))),
1554 Expression
=> New_Occurrence_Of
(Sel
, Loc
)));
1556 return Build_Task_Image_Function
(Loc
, Decls
, Stats
, Res
);
1557 end Build_Task_Record_Image
;
1559 -----------------------------
1560 -- Check_Float_Op_Overflow --
1561 -----------------------------
1563 procedure Check_Float_Op_Overflow
(N
: Node_Id
) is
1565 -- Return if no check needed
1567 if not Is_Floating_Point_Type
(Etype
(N
))
1568 or else not (Do_Overflow_Check
(N
) and then Check_Float_Overflow
)
1570 -- In CodePeer_Mode, rely on the overflow check flag being set instead
1571 -- and do not expand the code for float overflow checking.
1573 or else CodePeer_Mode
1578 -- Otherwise we replace the expression by
1580 -- do Tnn : constant ftype := expression;
1581 -- constraint_error when not Tnn'Valid;
1585 Loc
: constant Source_Ptr
:= Sloc
(N
);
1586 Tnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T', N
);
1587 Typ
: constant Entity_Id
:= Etype
(N
);
1590 -- Turn off the Do_Overflow_Check flag, since we are doing that work
1591 -- right here. We also set the node as analyzed to prevent infinite
1592 -- recursion from repeating the operation in the expansion.
1594 Set_Do_Overflow_Check
(N
, False);
1595 Set_Analyzed
(N
, True);
1597 -- Do the rewrite to include the check
1600 Make_Expression_With_Actions
(Loc
,
1601 Actions
=> New_List
(
1602 Make_Object_Declaration
(Loc
,
1603 Defining_Identifier
=> Tnn
,
1604 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
),
1605 Constant_Present
=> True,
1606 Expression
=> Relocate_Node
(N
)),
1607 Make_Raise_Constraint_Error
(Loc
,
1611 Make_Attribute_Reference
(Loc
,
1612 Prefix
=> New_Occurrence_Of
(Tnn
, Loc
),
1613 Attribute_Name
=> Name_Valid
)),
1614 Reason
=> CE_Overflow_Check_Failed
)),
1615 Expression
=> New_Occurrence_Of
(Tnn
, Loc
)));
1617 Analyze_And_Resolve
(N
, Typ
);
1619 end Check_Float_Op_Overflow
;
1621 ----------------------------------
1622 -- Component_May_Be_Bit_Aligned --
1623 ----------------------------------
1625 function Component_May_Be_Bit_Aligned
(Comp
: Entity_Id
) return Boolean is
1629 -- If no component clause, then everything is fine, since the back end
1630 -- never bit-misaligns by default, even if there is a pragma Packed for
1633 if No
(Comp
) or else No
(Component_Clause
(Comp
)) then
1637 UT
:= Underlying_Type
(Etype
(Comp
));
1639 -- It is only array and record types that cause trouble
1641 if not Is_Record_Type
(UT
) and then not Is_Array_Type
(UT
) then
1644 -- If we know that we have a small (64 bits or less) record or small
1645 -- bit-packed array, then everything is fine, since the back end can
1646 -- handle these cases correctly.
1648 elsif Esize
(Comp
) <= 64
1649 and then (Is_Record_Type
(UT
) or else Is_Bit_Packed_Array
(UT
))
1653 -- Otherwise if the component is not byte aligned, we know we have the
1654 -- nasty unaligned case.
1656 elsif Normalized_First_Bit
(Comp
) /= Uint_0
1657 or else Esize
(Comp
) mod System_Storage_Unit
/= Uint_0
1661 -- If we are large and byte aligned, then OK at this level
1666 end Component_May_Be_Bit_Aligned
;
1668 ----------------------------------------
1669 -- Containing_Package_With_Ext_Axioms --
1670 ----------------------------------------
1672 function Containing_Package_With_Ext_Axioms
1673 (E
: Entity_Id
) return Entity_Id
1676 First_Ax_Parent_Scope
: Entity_Id
;
1679 -- E is the package or generic package which is externally axiomatized
1681 if Ekind_In
(E
, E_Package
, E_Generic_Package
)
1682 and then Has_Annotate_Pragma_For_External_Axiomatization
(E
)
1687 -- If E's scope is axiomatized, E is axiomatized
1689 if Present
(Scope
(E
)) then
1690 First_Ax_Parent_Scope
:=
1691 Containing_Package_With_Ext_Axioms
(Scope
(E
));
1693 if Present
(First_Ax_Parent_Scope
) then
1694 return First_Ax_Parent_Scope
;
1699 -- Otherwise, if E is a package instance, it is axiomatized if the
1700 -- corresponding generic package is axiomatized.
1702 if Ekind
(E
) = E_Package
then
1703 if Nkind
(Parent
(E
)) = N_Defining_Program_Unit_Name
then
1704 Decl
:= Parent
(Parent
(E
));
1709 if Present
(Generic_Parent
(Decl
)) then
1711 Containing_Package_With_Ext_Axioms
(Generic_Parent
(Decl
));
1716 end Containing_Package_With_Ext_Axioms
;
1718 -------------------------------
1719 -- Convert_To_Actual_Subtype --
1720 -------------------------------
1722 procedure Convert_To_Actual_Subtype
(Exp
: Entity_Id
) is
1726 Act_ST
:= Get_Actual_Subtype
(Exp
);
1728 if Act_ST
= Etype
(Exp
) then
1731 Rewrite
(Exp
, Convert_To
(Act_ST
, Relocate_Node
(Exp
)));
1732 Analyze_And_Resolve
(Exp
, Act_ST
);
1734 end Convert_To_Actual_Subtype
;
1736 -----------------------------------
1737 -- Corresponding_Runtime_Package --
1738 -----------------------------------
1740 function Corresponding_Runtime_Package
(Typ
: Entity_Id
) return RTU_Id
is
1741 Pkg_Id
: RTU_Id
:= RTU_Null
;
1744 pragma Assert
(Is_Concurrent_Type
(Typ
));
1746 if Ekind
(Typ
) in Protected_Kind
then
1747 if Has_Entries
(Typ
)
1749 -- A protected type without entries that covers an interface and
1750 -- overrides the abstract routines with protected procedures is
1751 -- considered equivalent to a protected type with entries in the
1752 -- context of dispatching select statements. It is sufficient to
1753 -- check for the presence of an interface list in the declaration
1754 -- node to recognize this case.
1756 or else Present
(Interface_List
(Parent
(Typ
)))
1758 -- Protected types with interrupt handlers (when not using a
1759 -- restricted profile) are also considered equivalent to
1760 -- protected types with entries. The types which are used
1761 -- (Static_Interrupt_Protection and Dynamic_Interrupt_Protection)
1762 -- are derived from Protection_Entries.
1764 or else (Has_Attach_Handler
(Typ
) and then not Restricted_Profile
)
1765 or else Has_Interrupt_Handler
(Typ
)
1768 or else Restriction_Active
(No_Entry_Queue
) = False
1769 or else Restriction_Active
(No_Select_Statements
) = False
1770 or else Number_Entries
(Typ
) > 1
1771 or else (Has_Attach_Handler
(Typ
)
1772 and then not Restricted_Profile
)
1774 Pkg_Id
:= System_Tasking_Protected_Objects_Entries
;
1776 Pkg_Id
:= System_Tasking_Protected_Objects_Single_Entry
;
1780 Pkg_Id
:= System_Tasking_Protected_Objects
;
1785 end Corresponding_Runtime_Package
;
1787 -----------------------------------
1788 -- Current_Sem_Unit_Declarations --
1789 -----------------------------------
1791 function Current_Sem_Unit_Declarations
return List_Id
is
1792 U
: Node_Id
:= Unit
(Cunit
(Current_Sem_Unit
));
1796 -- If the current unit is a package body, locate the visible
1797 -- declarations of the package spec.
1799 if Nkind
(U
) = N_Package_Body
then
1800 U
:= Unit
(Library_Unit
(Cunit
(Current_Sem_Unit
)));
1803 if Nkind
(U
) = N_Package_Declaration
then
1804 U
:= Specification
(U
);
1805 Decls
:= Visible_Declarations
(U
);
1809 Set_Visible_Declarations
(U
, Decls
);
1813 Decls
:= Declarations
(U
);
1817 Set_Declarations
(U
, Decls
);
1822 end Current_Sem_Unit_Declarations
;
1824 -----------------------
1825 -- Duplicate_Subexpr --
1826 -----------------------
1828 function Duplicate_Subexpr
1830 Name_Req
: Boolean := False;
1831 Renaming_Req
: Boolean := False) return Node_Id
1834 Remove_Side_Effects
(Exp
, Name_Req
, Renaming_Req
);
1835 return New_Copy_Tree
(Exp
);
1836 end Duplicate_Subexpr
;
1838 ---------------------------------
1839 -- Duplicate_Subexpr_No_Checks --
1840 ---------------------------------
1842 function Duplicate_Subexpr_No_Checks
1844 Name_Req
: Boolean := False;
1845 Renaming_Req
: Boolean := False;
1846 Related_Id
: Entity_Id
:= Empty
;
1847 Is_Low_Bound
: Boolean := False;
1848 Is_High_Bound
: Boolean := False) return Node_Id
1855 Name_Req
=> Name_Req
,
1856 Renaming_Req
=> Renaming_Req
,
1857 Related_Id
=> Related_Id
,
1858 Is_Low_Bound
=> Is_Low_Bound
,
1859 Is_High_Bound
=> Is_High_Bound
);
1861 New_Exp
:= New_Copy_Tree
(Exp
);
1862 Remove_Checks
(New_Exp
);
1864 end Duplicate_Subexpr_No_Checks
;
1866 -----------------------------------
1867 -- Duplicate_Subexpr_Move_Checks --
1868 -----------------------------------
1870 function Duplicate_Subexpr_Move_Checks
1872 Name_Req
: Boolean := False;
1873 Renaming_Req
: Boolean := False) return Node_Id
1878 Remove_Side_Effects
(Exp
, Name_Req
, Renaming_Req
);
1879 New_Exp
:= New_Copy_Tree
(Exp
);
1880 Remove_Checks
(Exp
);
1882 end Duplicate_Subexpr_Move_Checks
;
1884 --------------------
1885 -- Ensure_Defined --
1886 --------------------
1888 procedure Ensure_Defined
(Typ
: Entity_Id
; N
: Node_Id
) is
1892 -- An itype reference must only be created if this is a local itype, so
1893 -- that gigi can elaborate it on the proper objstack.
1895 if Is_Itype
(Typ
) and then Scope
(Typ
) = Current_Scope
then
1896 IR
:= Make_Itype_Reference
(Sloc
(N
));
1897 Set_Itype
(IR
, Typ
);
1898 Insert_Action
(N
, IR
);
1902 --------------------
1903 -- Entry_Names_OK --
1904 --------------------
1906 function Entry_Names_OK
return Boolean is
1909 not Restricted_Profile
1910 and then not Global_Discard_Names
1911 and then not Restriction_Active
(No_Implicit_Heap_Allocations
)
1912 and then not Restriction_Active
(No_Local_Allocators
);
1919 procedure Evaluate_Name
(Nam
: Node_Id
) is
1920 K
: constant Node_Kind
:= Nkind
(Nam
);
1923 -- For an explicit dereference, we simply force the evaluation of the
1924 -- name expression. The dereference provides a value that is the address
1925 -- for the renamed object, and it is precisely this value that we want
1928 if K
= N_Explicit_Dereference
then
1929 Force_Evaluation
(Prefix
(Nam
));
1931 -- For a selected component, we simply evaluate the prefix
1933 elsif K
= N_Selected_Component
then
1934 Evaluate_Name
(Prefix
(Nam
));
1936 -- For an indexed component, or an attribute reference, we evaluate the
1937 -- prefix, which is itself a name, recursively, and then force the
1938 -- evaluation of all the subscripts (or attribute expressions).
1940 elsif Nkind_In
(K
, N_Indexed_Component
, N_Attribute_Reference
) then
1941 Evaluate_Name
(Prefix
(Nam
));
1947 E
:= First
(Expressions
(Nam
));
1948 while Present
(E
) loop
1949 Force_Evaluation
(E
);
1951 if Original_Node
(E
) /= E
then
1952 Set_Do_Range_Check
(E
, Do_Range_Check
(Original_Node
(E
)));
1959 -- For a slice, we evaluate the prefix, as for the indexed component
1960 -- case and then, if there is a range present, either directly or as the
1961 -- constraint of a discrete subtype indication, we evaluate the two
1962 -- bounds of this range.
1964 elsif K
= N_Slice
then
1965 Evaluate_Name
(Prefix
(Nam
));
1966 Evaluate_Slice_Bounds
(Nam
);
1968 -- For a type conversion, the expression of the conversion must be the
1969 -- name of an object, and we simply need to evaluate this name.
1971 elsif K
= N_Type_Conversion
then
1972 Evaluate_Name
(Expression
(Nam
));
1974 -- For a function call, we evaluate the call
1976 elsif K
= N_Function_Call
then
1977 Force_Evaluation
(Nam
);
1979 -- The remaining cases are direct name, operator symbol and character
1980 -- literal. In all these cases, we do nothing, since we want to
1981 -- reevaluate each time the renamed object is used.
1988 ---------------------------
1989 -- Evaluate_Slice_Bounds --
1990 ---------------------------
1992 procedure Evaluate_Slice_Bounds
(Slice
: Node_Id
) is
1993 DR
: constant Node_Id
:= Discrete_Range
(Slice
);
1998 if Nkind
(DR
) = N_Range
then
1999 Force_Evaluation
(Low_Bound
(DR
));
2000 Force_Evaluation
(High_Bound
(DR
));
2002 elsif Nkind
(DR
) = N_Subtype_Indication
then
2003 Constr
:= Constraint
(DR
);
2005 if Nkind
(Constr
) = N_Range_Constraint
then
2006 Rexpr
:= Range_Expression
(Constr
);
2008 Force_Evaluation
(Low_Bound
(Rexpr
));
2009 Force_Evaluation
(High_Bound
(Rexpr
));
2012 end Evaluate_Slice_Bounds
;
2014 ---------------------
2015 -- Evolve_And_Then --
2016 ---------------------
2018 procedure Evolve_And_Then
(Cond
: in out Node_Id
; Cond1
: Node_Id
) is
2024 Make_And_Then
(Sloc
(Cond1
),
2026 Right_Opnd
=> Cond1
);
2028 end Evolve_And_Then
;
2030 --------------------
2031 -- Evolve_Or_Else --
2032 --------------------
2034 procedure Evolve_Or_Else
(Cond
: in out Node_Id
; Cond1
: Node_Id
) is
2040 Make_Or_Else
(Sloc
(Cond1
),
2042 Right_Opnd
=> Cond1
);
2046 -----------------------------------------
2047 -- Expand_Static_Predicates_In_Choices --
2048 -----------------------------------------
2050 procedure Expand_Static_Predicates_In_Choices
(N
: Node_Id
) is
2051 pragma Assert
(Nkind_In
(N
, N_Case_Statement_Alternative
, N_Variant
));
2053 Choices
: constant List_Id
:= Discrete_Choices
(N
);
2061 Choice
:= First
(Choices
);
2062 while Present
(Choice
) loop
2063 Next_C
:= Next
(Choice
);
2065 -- Check for name of subtype with static predicate
2067 if Is_Entity_Name
(Choice
)
2068 and then Is_Type
(Entity
(Choice
))
2069 and then Has_Predicates
(Entity
(Choice
))
2071 -- Loop through entries in predicate list, converting to choices
2072 -- and inserting in the list before the current choice. Note that
2073 -- if the list is empty, corresponding to a False predicate, then
2074 -- no choices are inserted.
2076 P
:= First
(Static_Discrete_Predicate
(Entity
(Choice
)));
2077 while Present
(P
) loop
2079 -- If low bound and high bounds are equal, copy simple choice
2081 if Expr_Value
(Low_Bound
(P
)) = Expr_Value
(High_Bound
(P
)) then
2082 C
:= New_Copy
(Low_Bound
(P
));
2084 -- Otherwise copy a range
2090 -- Change Sloc to referencing choice (rather than the Sloc of
2091 -- the predicate declaration element itself).
2093 Set_Sloc
(C
, Sloc
(Choice
));
2094 Insert_Before
(Choice
, C
);
2098 -- Delete the predicated entry
2103 -- Move to next choice to check
2107 end Expand_Static_Predicates_In_Choices
;
2109 ------------------------------
2110 -- Expand_Subtype_From_Expr --
2111 ------------------------------
2113 -- This function is applicable for both static and dynamic allocation of
2114 -- objects which are constrained by an initial expression. Basically it
2115 -- transforms an unconstrained subtype indication into a constrained one.
2117 -- The expression may also be transformed in certain cases in order to
2118 -- avoid multiple evaluation. In the static allocation case, the general
2123 -- is transformed into
2125 -- Val : Constrained_Subtype_of_T := Maybe_Modified_Expr;
2127 -- Here are the main cases :
2129 -- <if Expr is a Slice>
2130 -- Val : T ([Index_Subtype (Expr)]) := Expr;
2132 -- <elsif Expr is a String Literal>
2133 -- Val : T (T'First .. T'First + Length (string literal) - 1) := Expr;
2135 -- <elsif Expr is Constrained>
2136 -- subtype T is Type_Of_Expr
2139 -- <elsif Expr is an entity_name>
2140 -- Val : T (constraints taken from Expr) := Expr;
2143 -- type Axxx is access all T;
2144 -- Rval : Axxx := Expr'ref;
2145 -- Val : T (constraints taken from Rval) := Rval.all;
2147 -- ??? note: when the Expression is allocated in the secondary stack
2148 -- we could use it directly instead of copying it by declaring
2149 -- Val : T (...) renames Rval.all
2151 procedure Expand_Subtype_From_Expr
2153 Unc_Type
: Entity_Id
;
2154 Subtype_Indic
: Node_Id
;
2156 Related_Id
: Entity_Id
:= Empty
)
2158 Loc
: constant Source_Ptr
:= Sloc
(N
);
2159 Exp_Typ
: constant Entity_Id
:= Etype
(Exp
);
2163 -- In general we cannot build the subtype if expansion is disabled,
2164 -- because internal entities may not have been defined. However, to
2165 -- avoid some cascaded errors, we try to continue when the expression is
2166 -- an array (or string), because it is safe to compute the bounds. It is
2167 -- in fact required to do so even in a generic context, because there
2168 -- may be constants that depend on the bounds of a string literal, both
2169 -- standard string types and more generally arrays of characters.
2171 -- In GNATprove mode, these extra subtypes are not needed
2173 if GNATprove_Mode
then
2177 if not Expander_Active
2178 and then (No
(Etype
(Exp
)) or else not Is_String_Type
(Etype
(Exp
)))
2183 if Nkind
(Exp
) = N_Slice
then
2185 Slice_Type
: constant Entity_Id
:= Etype
(First_Index
(Exp_Typ
));
2188 Rewrite
(Subtype_Indic
,
2189 Make_Subtype_Indication
(Loc
,
2190 Subtype_Mark
=> New_Occurrence_Of
(Unc_Type
, Loc
),
2192 Make_Index_Or_Discriminant_Constraint
(Loc
,
2193 Constraints
=> New_List
2194 (New_Occurrence_Of
(Slice_Type
, Loc
)))));
2196 -- This subtype indication may be used later for constraint checks
2197 -- we better make sure that if a variable was used as a bound of
2198 -- of the original slice, its value is frozen.
2200 Evaluate_Slice_Bounds
(Exp
);
2203 elsif Ekind
(Exp_Typ
) = E_String_Literal_Subtype
then
2204 Rewrite
(Subtype_Indic
,
2205 Make_Subtype_Indication
(Loc
,
2206 Subtype_Mark
=> New_Occurrence_Of
(Unc_Type
, Loc
),
2208 Make_Index_Or_Discriminant_Constraint
(Loc
,
2209 Constraints
=> New_List
(
2210 Make_Literal_Range
(Loc
,
2211 Literal_Typ
=> Exp_Typ
)))));
2213 -- If the type of the expression is an internally generated type it
2214 -- may not be necessary to create a new subtype. However there are two
2215 -- exceptions: references to the current instances, and aliased array
2216 -- object declarations for which the backend needs to create a template.
2218 elsif Is_Constrained
(Exp_Typ
)
2219 and then not Is_Class_Wide_Type
(Unc_Type
)
2221 (Nkind
(N
) /= N_Object_Declaration
2222 or else not Is_Entity_Name
(Expression
(N
))
2223 or else not Comes_From_Source
(Entity
(Expression
(N
)))
2224 or else not Is_Array_Type
(Exp_Typ
)
2225 or else not Aliased_Present
(N
))
2227 if Is_Itype
(Exp_Typ
) then
2229 -- Within an initialization procedure, a selected component
2230 -- denotes a component of the enclosing record, and it appears as
2231 -- an actual in a call to its own initialization procedure. If
2232 -- this component depends on the outer discriminant, we must
2233 -- generate the proper actual subtype for it.
2235 if Nkind
(Exp
) = N_Selected_Component
2236 and then Within_Init_Proc
2239 Decl
: constant Node_Id
:=
2240 Build_Actual_Subtype_Of_Component
(Exp_Typ
, Exp
);
2242 if Present
(Decl
) then
2243 Insert_Action
(N
, Decl
);
2244 T
:= Defining_Identifier
(Decl
);
2250 -- No need to generate a new subtype
2257 T
:= Make_Temporary
(Loc
, 'T');
2260 Make_Subtype_Declaration
(Loc
,
2261 Defining_Identifier
=> T
,
2262 Subtype_Indication
=> New_Occurrence_Of
(Exp_Typ
, Loc
)));
2264 -- This type is marked as an itype even though it has an explicit
2265 -- declaration since otherwise Is_Generic_Actual_Type can get
2266 -- set, resulting in the generation of spurious errors. (See
2267 -- sem_ch8.Analyze_Package_Renaming and sem_type.covers)
2270 Set_Associated_Node_For_Itype
(T
, Exp
);
2273 Rewrite
(Subtype_Indic
, New_Occurrence_Of
(T
, Loc
));
2275 -- Nothing needs to be done for private types with unknown discriminants
2276 -- if the underlying type is not an unconstrained composite type or it
2277 -- is an unchecked union.
2279 elsif Is_Private_Type
(Unc_Type
)
2280 and then Has_Unknown_Discriminants
(Unc_Type
)
2281 and then (not Is_Composite_Type
(Underlying_Type
(Unc_Type
))
2282 or else Is_Constrained
(Underlying_Type
(Unc_Type
))
2283 or else Is_Unchecked_Union
(Underlying_Type
(Unc_Type
)))
2287 -- Case of derived type with unknown discriminants where the parent type
2288 -- also has unknown discriminants.
2290 elsif Is_Record_Type
(Unc_Type
)
2291 and then not Is_Class_Wide_Type
(Unc_Type
)
2292 and then Has_Unknown_Discriminants
(Unc_Type
)
2293 and then Has_Unknown_Discriminants
(Underlying_Type
(Unc_Type
))
2295 -- Nothing to be done if no underlying record view available
2297 if No
(Underlying_Record_View
(Unc_Type
)) then
2300 -- Otherwise use the Underlying_Record_View to create the proper
2301 -- constrained subtype for an object of a derived type with unknown
2305 Remove_Side_Effects
(Exp
);
2306 Rewrite
(Subtype_Indic
,
2307 Make_Subtype_From_Expr
(Exp
, Underlying_Record_View
(Unc_Type
)));
2310 -- Renamings of class-wide interface types require no equivalent
2311 -- constrained type declarations because we only need to reference
2312 -- the tag component associated with the interface. The same is
2313 -- presumably true for class-wide types in general, so this test
2314 -- is broadened to include all class-wide renamings, which also
2315 -- avoids cases of unbounded recursion in Remove_Side_Effects.
2316 -- (Is this really correct, or are there some cases of class-wide
2317 -- renamings that require action in this procedure???)
2320 and then Nkind
(N
) = N_Object_Renaming_Declaration
2321 and then Is_Class_Wide_Type
(Unc_Type
)
2325 -- In Ada 95 nothing to be done if the type of the expression is limited
2326 -- because in this case the expression cannot be copied, and its use can
2327 -- only be by reference.
2329 -- In Ada 2005 the context can be an object declaration whose expression
2330 -- is a function that returns in place. If the nominal subtype has
2331 -- unknown discriminants, the call still provides constraints on the
2332 -- object, and we have to create an actual subtype from it.
2334 -- If the type is class-wide, the expression is dynamically tagged and
2335 -- we do not create an actual subtype either. Ditto for an interface.
2336 -- For now this applies only if the type is immutably limited, and the
2337 -- function being called is build-in-place. This will have to be revised
2338 -- when build-in-place functions are generalized to other types.
2340 elsif Is_Limited_View
(Exp_Typ
)
2342 (Is_Class_Wide_Type
(Exp_Typ
)
2343 or else Is_Interface
(Exp_Typ
)
2344 or else not Has_Unknown_Discriminants
(Exp_Typ
)
2345 or else not Is_Composite_Type
(Unc_Type
))
2349 -- For limited objects initialized with build in place function calls,
2350 -- nothing to be done; otherwise we prematurely introduce an N_Reference
2351 -- node in the expression initializing the object, which breaks the
2352 -- circuitry that detects and adds the additional arguments to the
2355 elsif Is_Build_In_Place_Function_Call
(Exp
) then
2359 Remove_Side_Effects
(Exp
);
2360 Rewrite
(Subtype_Indic
,
2361 Make_Subtype_From_Expr
(Exp
, Unc_Type
, Related_Id
));
2363 end Expand_Subtype_From_Expr
;
2365 ----------------------
2366 -- Finalize_Address --
2367 ----------------------
2369 function Finalize_Address
(Typ
: Entity_Id
) return Entity_Id
is
2370 Utyp
: Entity_Id
:= Typ
;
2373 -- Handle protected class-wide or task class-wide types
2375 if Is_Class_Wide_Type
(Utyp
) then
2376 if Is_Concurrent_Type
(Root_Type
(Utyp
)) then
2377 Utyp
:= Root_Type
(Utyp
);
2379 elsif Is_Private_Type
(Root_Type
(Utyp
))
2380 and then Present
(Full_View
(Root_Type
(Utyp
)))
2381 and then Is_Concurrent_Type
(Full_View
(Root_Type
(Utyp
)))
2383 Utyp
:= Full_View
(Root_Type
(Utyp
));
2387 -- Handle private types
2389 if Is_Private_Type
(Utyp
) and then Present
(Full_View
(Utyp
)) then
2390 Utyp
:= Full_View
(Utyp
);
2393 -- Handle protected and task types
2395 if Is_Concurrent_Type
(Utyp
)
2396 and then Present
(Corresponding_Record_Type
(Utyp
))
2398 Utyp
:= Corresponding_Record_Type
(Utyp
);
2401 Utyp
:= Underlying_Type
(Base_Type
(Utyp
));
2403 -- Deal with untagged derivation of private views. If the parent is
2404 -- now known to be protected, the finalization routine is the one
2405 -- defined on the corresponding record of the ancestor (corresponding
2406 -- records do not automatically inherit operations, but maybe they
2409 if Is_Untagged_Derivation
(Typ
) then
2410 if Is_Protected_Type
(Typ
) then
2411 Utyp
:= Corresponding_Record_Type
(Root_Type
(Base_Type
(Typ
)));
2414 Utyp
:= Underlying_Type
(Root_Type
(Base_Type
(Typ
)));
2416 if Is_Protected_Type
(Utyp
) then
2417 Utyp
:= Corresponding_Record_Type
(Utyp
);
2422 -- If the underlying_type is a subtype, we are dealing with the
2423 -- completion of a private type. We need to access the base type and
2424 -- generate a conversion to it.
2426 if Utyp
/= Base_Type
(Utyp
) then
2427 pragma Assert
(Is_Private_Type
(Typ
));
2429 Utyp
:= Base_Type
(Utyp
);
2432 -- When dealing with an internally built full view for a type with
2433 -- unknown discriminants, use the original record type.
2435 if Is_Underlying_Record_View
(Utyp
) then
2436 Utyp
:= Etype
(Utyp
);
2439 return TSS
(Utyp
, TSS_Finalize_Address
);
2440 end Finalize_Address
;
2442 ------------------------
2443 -- Find_Interface_ADT --
2444 ------------------------
2446 function Find_Interface_ADT
2448 Iface
: Entity_Id
) return Elmt_Id
2451 Typ
: Entity_Id
:= T
;
2454 pragma Assert
(Is_Interface
(Iface
));
2456 -- Handle private types
2458 if Has_Private_Declaration
(Typ
) and then Present
(Full_View
(Typ
)) then
2459 Typ
:= Full_View
(Typ
);
2462 -- Handle access types
2464 if Is_Access_Type
(Typ
) then
2465 Typ
:= Designated_Type
(Typ
);
2468 -- Handle task and protected types implementing interfaces
2470 if Is_Concurrent_Type
(Typ
) then
2471 Typ
:= Corresponding_Record_Type
(Typ
);
2475 (not Is_Class_Wide_Type
(Typ
)
2476 and then Ekind
(Typ
) /= E_Incomplete_Type
);
2478 if Is_Ancestor
(Iface
, Typ
, Use_Full_View
=> True) then
2479 return First_Elmt
(Access_Disp_Table
(Typ
));
2482 ADT
:= Next_Elmt
(Next_Elmt
(First_Elmt
(Access_Disp_Table
(Typ
))));
2484 and then Present
(Related_Type
(Node
(ADT
)))
2485 and then Related_Type
(Node
(ADT
)) /= Iface
2486 and then not Is_Ancestor
(Iface
, Related_Type
(Node
(ADT
)),
2487 Use_Full_View
=> True)
2492 pragma Assert
(Present
(Related_Type
(Node
(ADT
))));
2495 end Find_Interface_ADT
;
2497 ------------------------
2498 -- Find_Interface_Tag --
2499 ------------------------
2501 function Find_Interface_Tag
2503 Iface
: Entity_Id
) return Entity_Id
2506 Found
: Boolean := False;
2507 Typ
: Entity_Id
:= T
;
2509 procedure Find_Tag
(Typ
: Entity_Id
);
2510 -- Internal subprogram used to recursively climb to the ancestors
2516 procedure Find_Tag
(Typ
: Entity_Id
) is
2521 -- This routine does not handle the case in which the interface is an
2522 -- ancestor of Typ. That case is handled by the enclosing subprogram.
2524 pragma Assert
(Typ
/= Iface
);
2526 -- Climb to the root type handling private types
2528 if Present
(Full_View
(Etype
(Typ
))) then
2529 if Full_View
(Etype
(Typ
)) /= Typ
then
2530 Find_Tag
(Full_View
(Etype
(Typ
)));
2533 elsif Etype
(Typ
) /= Typ
then
2534 Find_Tag
(Etype
(Typ
));
2537 -- Traverse the list of interfaces implemented by the type
2540 and then Present
(Interfaces
(Typ
))
2541 and then not (Is_Empty_Elmt_List
(Interfaces
(Typ
)))
2543 -- Skip the tag associated with the primary table
2545 pragma Assert
(Etype
(First_Tag_Component
(Typ
)) = RTE
(RE_Tag
));
2546 AI_Tag
:= Next_Tag_Component
(First_Tag_Component
(Typ
));
2547 pragma Assert
(Present
(AI_Tag
));
2549 AI_Elmt
:= First_Elmt
(Interfaces
(Typ
));
2550 while Present
(AI_Elmt
) loop
2551 AI
:= Node
(AI_Elmt
);
2554 or else Is_Ancestor
(Iface
, AI
, Use_Full_View
=> True)
2560 AI_Tag
:= Next_Tag_Component
(AI_Tag
);
2561 Next_Elmt
(AI_Elmt
);
2566 -- Start of processing for Find_Interface_Tag
2569 pragma Assert
(Is_Interface
(Iface
));
2571 -- Handle access types
2573 if Is_Access_Type
(Typ
) then
2574 Typ
:= Designated_Type
(Typ
);
2577 -- Handle class-wide types
2579 if Is_Class_Wide_Type
(Typ
) then
2580 Typ
:= Root_Type
(Typ
);
2583 -- Handle private types
2585 if Has_Private_Declaration
(Typ
) and then Present
(Full_View
(Typ
)) then
2586 Typ
:= Full_View
(Typ
);
2589 -- Handle entities from the limited view
2591 if Ekind
(Typ
) = E_Incomplete_Type
then
2592 pragma Assert
(Present
(Non_Limited_View
(Typ
)));
2593 Typ
:= Non_Limited_View
(Typ
);
2596 -- Handle task and protected types implementing interfaces
2598 if Is_Concurrent_Type
(Typ
) then
2599 Typ
:= Corresponding_Record_Type
(Typ
);
2602 -- If the interface is an ancestor of the type, then it shared the
2603 -- primary dispatch table.
2605 if Is_Ancestor
(Iface
, Typ
, Use_Full_View
=> True) then
2606 pragma Assert
(Etype
(First_Tag_Component
(Typ
)) = RTE
(RE_Tag
));
2607 return First_Tag_Component
(Typ
);
2609 -- Otherwise we need to search for its associated tag component
2613 pragma Assert
(Found
);
2616 end Find_Interface_Tag
;
2618 ---------------------------
2619 -- Find_Optional_Prim_Op --
2620 ---------------------------
2622 function Find_Optional_Prim_Op
2623 (T
: Entity_Id
; Name
: Name_Id
) return Entity_Id
2626 Typ
: Entity_Id
:= T
;
2630 if Is_Class_Wide_Type
(Typ
) then
2631 Typ
:= Root_Type
(Typ
);
2634 Typ
:= Underlying_Type
(Typ
);
2636 -- Loop through primitive operations
2638 Prim
:= First_Elmt
(Primitive_Operations
(Typ
));
2639 while Present
(Prim
) loop
2642 -- We can retrieve primitive operations by name if it is an internal
2643 -- name. For equality we must check that both of its operands have
2644 -- the same type, to avoid confusion with user-defined equalities
2645 -- than may have a non-symmetric signature.
2647 exit when Chars
(Op
) = Name
2650 or else Etype
(First_Formal
(Op
)) = Etype
(Last_Formal
(Op
)));
2655 return Node
(Prim
); -- Empty if not found
2656 end Find_Optional_Prim_Op
;
2658 ---------------------------
2659 -- Find_Optional_Prim_Op --
2660 ---------------------------
2662 function Find_Optional_Prim_Op
2664 Name
: TSS_Name_Type
) return Entity_Id
2666 Inher_Op
: Entity_Id
:= Empty
;
2667 Own_Op
: Entity_Id
:= Empty
;
2668 Prim_Elmt
: Elmt_Id
;
2669 Prim_Id
: Entity_Id
;
2670 Typ
: Entity_Id
:= T
;
2673 if Is_Class_Wide_Type
(Typ
) then
2674 Typ
:= Root_Type
(Typ
);
2677 Typ
:= Underlying_Type
(Typ
);
2679 -- This search is based on the assertion that the dispatching version
2680 -- of the TSS routine always precedes the real primitive.
2682 Prim_Elmt
:= First_Elmt
(Primitive_Operations
(Typ
));
2683 while Present
(Prim_Elmt
) loop
2684 Prim_Id
:= Node
(Prim_Elmt
);
2686 if Is_TSS
(Prim_Id
, Name
) then
2687 if Present
(Alias
(Prim_Id
)) then
2688 Inher_Op
:= Prim_Id
;
2694 Next_Elmt
(Prim_Elmt
);
2697 if Present
(Own_Op
) then
2699 elsif Present
(Inher_Op
) then
2704 end Find_Optional_Prim_Op
;
2706 -------------------------------
2707 -- Find_Primitive_Operations --
2708 -------------------------------
2710 function Find_Primitive_Operations
2712 Name
: Name_Id
) return Node_Id
2714 Prim_Elmt
: Elmt_Id
;
2715 Prim_Id
: Entity_Id
;
2717 Typ
: Entity_Id
:= T
;
2720 if Is_Class_Wide_Type
(Typ
) then
2721 Typ
:= Root_Type
(Typ
);
2724 Typ
:= Underlying_Type
(Typ
);
2727 Prim_Elmt
:= First_Elmt
(Primitive_Operations
(Typ
));
2728 while Present
(Prim_Elmt
) loop
2729 Prim_Id
:= Node
(Prim_Elmt
);
2730 if Chars
(Prim_Id
) = Name
then
2732 -- If this is the first primitive operation found,
2733 -- create a reference to it.
2736 Ref
:= New_Occurrence_Of
(Prim_Id
, Sloc
(T
));
2738 -- Otherwise, add interpretation to existing reference
2741 Add_One_Interp
(Ref
, Prim_Id
, Etype
(Prim_Id
));
2744 Next_Elmt
(Prim_Elmt
);
2748 end Find_Primitive_Operations
;
2754 function Find_Prim_Op
2755 (T
: Entity_Id
; Name
: Name_Id
) return Entity_Id
2757 Result
: constant Entity_Id
:= Find_Optional_Prim_Op
(T
, Name
);
2760 raise Program_Error
;
2770 function Find_Prim_Op
2772 Name
: TSS_Name_Type
) return Entity_Id
2774 Result
: constant Entity_Id
:= Find_Optional_Prim_Op
(T
, Name
);
2777 raise Program_Error
;
2783 ----------------------------
2784 -- Find_Protection_Object --
2785 ----------------------------
2787 function Find_Protection_Object
(Scop
: Entity_Id
) return Entity_Id
is
2792 while Present
(S
) loop
2793 if Ekind_In
(S
, E_Entry
, E_Entry_Family
, E_Function
, E_Procedure
)
2794 and then Present
(Protection_Object
(S
))
2796 return Protection_Object
(S
);
2802 -- If we do not find a Protection object in the scope chain, then
2803 -- something has gone wrong, most likely the object was never created.
2805 raise Program_Error
;
2806 end Find_Protection_Object
;
2808 --------------------------
2809 -- Find_Protection_Type --
2810 --------------------------
2812 function Find_Protection_Type
(Conc_Typ
: Entity_Id
) return Entity_Id
is
2814 Typ
: Entity_Id
:= Conc_Typ
;
2817 if Is_Concurrent_Type
(Typ
) then
2818 Typ
:= Corresponding_Record_Type
(Typ
);
2821 -- Since restriction violations are not considered serious errors, the
2822 -- expander remains active, but may leave the corresponding record type
2823 -- malformed. In such cases, component _object is not available so do
2826 if not Analyzed
(Typ
) then
2830 Comp
:= First_Component
(Typ
);
2831 while Present
(Comp
) loop
2832 if Chars
(Comp
) = Name_uObject
then
2833 return Base_Type
(Etype
(Comp
));
2836 Next_Component
(Comp
);
2839 -- The corresponding record of a protected type should always have an
2842 raise Program_Error
;
2843 end Find_Protection_Type
;
2845 -----------------------
2846 -- Find_Hook_Context --
2847 -----------------------
2849 function Find_Hook_Context
(N
: Node_Id
) return Node_Id
is
2853 Wrapped_Node
: Node_Id
;
2854 -- Note: if we are in a transient scope, we want to reuse it as
2855 -- the context for actions insertion, if possible. But if N is itself
2856 -- part of the stored actions for the current transient scope,
2857 -- then we need to insert at the appropriate (inner) location in
2858 -- the not as an action on Node_To_Be_Wrapped.
2860 In_Cond_Expr
: constant Boolean := Within_Case_Or_If_Expression
(N
);
2863 -- When the node is inside a case/if expression, the lifetime of any
2864 -- temporary controlled object is extended. Find a suitable insertion
2865 -- node by locating the topmost case or if expressions.
2867 if In_Cond_Expr
then
2870 while Present
(Par
) loop
2871 if Nkind_In
(Original_Node
(Par
), N_Case_Expression
,
2876 -- Prevent the search from going too far
2878 elsif Is_Body_Or_Package_Declaration
(Par
) then
2882 Par
:= Parent
(Par
);
2885 -- The topmost case or if expression is now recovered, but it may
2886 -- still not be the correct place to add generated code. Climb to
2887 -- find a parent that is part of a declarative or statement list,
2888 -- and is not a list of actuals in a call.
2891 while Present
(Par
) loop
2892 if Is_List_Member
(Par
)
2893 and then not Nkind_In
(Par
, N_Component_Association
,
2894 N_Discriminant_Association
,
2895 N_Parameter_Association
,
2896 N_Pragma_Argument_Association
)
2897 and then not Nkind_In
2898 (Parent
(Par
), N_Function_Call
,
2899 N_Procedure_Call_Statement
,
2900 N_Entry_Call_Statement
)
2905 -- Prevent the search from going too far
2907 elsif Is_Body_Or_Package_Declaration
(Par
) then
2911 Par
:= Parent
(Par
);
2918 while Present
(Par
) loop
2920 -- Keep climbing past various operators
2922 if Nkind
(Parent
(Par
)) in N_Op
2923 or else Nkind_In
(Parent
(Par
), N_And_Then
, N_Or_Else
)
2925 Par
:= Parent
(Par
);
2933 -- The node may be located in a pragma in which case return the
2936 -- pragma Precondition (... and then Ctrl_Func_Call ...);
2938 -- Similar case occurs when the node is related to an object
2939 -- declaration or assignment:
2941 -- Obj [: Some_Typ] := ... and then Ctrl_Func_Call ...;
2943 -- Another case to consider is when the node is part of a return
2946 -- return ... and then Ctrl_Func_Call ...;
2948 -- Another case is when the node acts as a formal in a procedure
2951 -- Proc (... and then Ctrl_Func_Call ...);
2953 if Scope_Is_Transient
then
2954 Wrapped_Node
:= Node_To_Be_Wrapped
;
2956 Wrapped_Node
:= Empty
;
2959 while Present
(Par
) loop
2960 if Par
= Wrapped_Node
2961 or else Nkind_In
(Par
, N_Assignment_Statement
,
2962 N_Object_Declaration
,
2964 N_Procedure_Call_Statement
,
2965 N_Simple_Return_Statement
)
2969 -- Prevent the search from going too far
2971 elsif Is_Body_Or_Package_Declaration
(Par
) then
2975 Par
:= Parent
(Par
);
2978 -- Return the topmost short circuit operator
2982 end Find_Hook_Context
;
2984 ------------------------------
2985 -- Following_Address_Clause --
2986 ------------------------------
2988 function Following_Address_Clause
(D
: Node_Id
) return Node_Id
is
2989 Id
: constant Entity_Id
:= Defining_Identifier
(D
);
2993 function Check_Decls
(D
: Node_Id
) return Node_Id
;
2994 -- This internal function differs from the main function in that it
2995 -- gets called to deal with a following package private part, and
2996 -- it checks declarations starting with D (the main function checks
2997 -- declarations following D). If D is Empty, then Empty is returned.
3003 function Check_Decls
(D
: Node_Id
) return Node_Id
is
3008 while Present
(Decl
) loop
3009 if Nkind
(Decl
) = N_At_Clause
3010 and then Chars
(Identifier
(Decl
)) = Chars
(Id
)
3014 elsif Nkind
(Decl
) = N_Attribute_Definition_Clause
3015 and then Chars
(Decl
) = Name_Address
3016 and then Chars
(Name
(Decl
)) = Chars
(Id
)
3024 -- Otherwise not found, return Empty
3029 -- Start of processing for Following_Address_Clause
3032 -- If parser detected no address clause for the identifier in question,
3033 -- then the answer is a quick NO, without the need for a search.
3035 if not Get_Name_Table_Boolean1
(Chars
(Id
)) then
3039 -- Otherwise search current declarative unit
3041 Result
:= Check_Decls
(Next
(D
));
3043 if Present
(Result
) then
3047 -- Check for possible package private part following
3051 if Nkind
(Par
) = N_Package_Specification
3052 and then Visible_Declarations
(Par
) = List_Containing
(D
)
3053 and then Present
(Private_Declarations
(Par
))
3055 -- Private part present, check declarations there
3057 return Check_Decls
(First
(Private_Declarations
(Par
)));
3060 -- No private part, clause not found, return Empty
3064 end Following_Address_Clause
;
3066 ----------------------
3067 -- Force_Evaluation --
3068 ----------------------
3070 procedure Force_Evaluation
3072 Name_Req
: Boolean := False;
3073 Related_Id
: Entity_Id
:= Empty
;
3074 Is_Low_Bound
: Boolean := False;
3075 Is_High_Bound
: Boolean := False)
3080 Name_Req
=> Name_Req
,
3081 Variable_Ref
=> True,
3082 Renaming_Req
=> False,
3083 Related_Id
=> Related_Id
,
3084 Is_Low_Bound
=> Is_Low_Bound
,
3085 Is_High_Bound
=> Is_High_Bound
);
3086 end Force_Evaluation
;
3088 ---------------------------------
3089 -- Fully_Qualified_Name_String --
3090 ---------------------------------
3092 function Fully_Qualified_Name_String
3094 Append_NUL
: Boolean := True) return String_Id
3096 procedure Internal_Full_Qualified_Name
(E
: Entity_Id
);
3097 -- Compute recursively the qualified name without NUL at the end, adding
3098 -- it to the currently started string being generated
3100 ----------------------------------
3101 -- Internal_Full_Qualified_Name --
3102 ----------------------------------
3104 procedure Internal_Full_Qualified_Name
(E
: Entity_Id
) is
3108 -- Deal properly with child units
3110 if Nkind
(E
) = N_Defining_Program_Unit_Name
then
3111 Ent
:= Defining_Identifier
(E
);
3116 -- Compute qualification recursively (only "Standard" has no scope)
3118 if Present
(Scope
(Scope
(Ent
))) then
3119 Internal_Full_Qualified_Name
(Scope
(Ent
));
3120 Store_String_Char
(Get_Char_Code
('.'));
3123 -- Every entity should have a name except some expanded blocks
3124 -- don't bother about those.
3126 if Chars
(Ent
) = No_Name
then
3130 -- Generates the entity name in upper case
3132 Get_Decoded_Name_String
(Chars
(Ent
));
3134 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
3136 end Internal_Full_Qualified_Name
;
3138 -- Start of processing for Full_Qualified_Name
3142 Internal_Full_Qualified_Name
(E
);
3145 Store_String_Char
(Get_Char_Code
(ASCII
.NUL
));
3149 end Fully_Qualified_Name_String
;
3151 ------------------------
3152 -- Generate_Poll_Call --
3153 ------------------------
3155 procedure Generate_Poll_Call
(N
: Node_Id
) is
3157 -- No poll call if polling not active
3159 if not Polling_Required
then
3162 -- Otherwise generate require poll call
3165 Insert_Before_And_Analyze
(N
,
3166 Make_Procedure_Call_Statement
(Sloc
(N
),
3167 Name
=> New_Occurrence_Of
(RTE
(RE_Poll
), Sloc
(N
))));
3169 end Generate_Poll_Call
;
3171 ---------------------------------
3172 -- Get_Current_Value_Condition --
3173 ---------------------------------
3175 -- Note: the implementation of this procedure is very closely tied to the
3176 -- implementation of Set_Current_Value_Condition. In the Get procedure, we
3177 -- interpret Current_Value fields set by the Set procedure, so the two
3178 -- procedures need to be closely coordinated.
3180 procedure Get_Current_Value_Condition
3185 Loc
: constant Source_Ptr
:= Sloc
(Var
);
3186 Ent
: constant Entity_Id
:= Entity
(Var
);
3188 procedure Process_Current_Value_Condition
3191 -- N is an expression which holds either True (S = True) or False (S =
3192 -- False) in the condition. This procedure digs out the expression and
3193 -- if it refers to Ent, sets Op and Val appropriately.
3195 -------------------------------------
3196 -- Process_Current_Value_Condition --
3197 -------------------------------------
3199 procedure Process_Current_Value_Condition
3204 Prev_Cond
: Node_Id
;
3214 -- Deal with NOT operators, inverting sense
3216 while Nkind
(Cond
) = N_Op_Not
loop
3217 Cond
:= Right_Opnd
(Cond
);
3221 -- Deal with conversions, qualifications, and expressions with
3224 while Nkind_In
(Cond
,
3226 N_Qualified_Expression
,
3227 N_Expression_With_Actions
)
3229 Cond
:= Expression
(Cond
);
3232 exit when Cond
= Prev_Cond
;
3235 -- Deal with AND THEN and AND cases
3237 if Nkind_In
(Cond
, N_And_Then
, N_Op_And
) then
3239 -- Don't ever try to invert a condition that is of the form of an
3240 -- AND or AND THEN (since we are not doing sufficiently general
3241 -- processing to allow this).
3243 if Sens
= False then
3249 -- Recursively process AND and AND THEN branches
3251 Process_Current_Value_Condition
(Left_Opnd
(Cond
), True);
3253 if Op
/= N_Empty
then
3257 Process_Current_Value_Condition
(Right_Opnd
(Cond
), True);
3260 -- Case of relational operator
3262 elsif Nkind
(Cond
) in N_Op_Compare
then
3265 -- Invert sense of test if inverted test
3267 if Sens
= False then
3269 when N_Op_Eq
=> Op
:= N_Op_Ne
;
3270 when N_Op_Ne
=> Op
:= N_Op_Eq
;
3271 when N_Op_Lt
=> Op
:= N_Op_Ge
;
3272 when N_Op_Gt
=> Op
:= N_Op_Le
;
3273 when N_Op_Le
=> Op
:= N_Op_Gt
;
3274 when N_Op_Ge
=> Op
:= N_Op_Lt
;
3275 when others => raise Program_Error
;
3279 -- Case of entity op value
3281 if Is_Entity_Name
(Left_Opnd
(Cond
))
3282 and then Ent
= Entity
(Left_Opnd
(Cond
))
3283 and then Compile_Time_Known_Value
(Right_Opnd
(Cond
))
3285 Val
:= Right_Opnd
(Cond
);
3287 -- Case of value op entity
3289 elsif Is_Entity_Name
(Right_Opnd
(Cond
))
3290 and then Ent
= Entity
(Right_Opnd
(Cond
))
3291 and then Compile_Time_Known_Value
(Left_Opnd
(Cond
))
3293 Val
:= Left_Opnd
(Cond
);
3295 -- We are effectively swapping operands
3298 when N_Op_Eq
=> null;
3299 when N_Op_Ne
=> null;
3300 when N_Op_Lt
=> Op
:= N_Op_Gt
;
3301 when N_Op_Gt
=> Op
:= N_Op_Lt
;
3302 when N_Op_Le
=> Op
:= N_Op_Ge
;
3303 when N_Op_Ge
=> Op
:= N_Op_Le
;
3304 when others => raise Program_Error
;
3313 elsif Nkind_In
(Cond
,
3315 N_Qualified_Expression
,
3316 N_Expression_With_Actions
)
3318 Cond
:= Expression
(Cond
);
3320 -- Case of Boolean variable reference, return as though the
3321 -- reference had said var = True.
3324 if Is_Entity_Name
(Cond
) and then Ent
= Entity
(Cond
) then
3325 Val
:= New_Occurrence_Of
(Standard_True
, Sloc
(Cond
));
3327 if Sens
= False then
3334 end Process_Current_Value_Condition
;
3336 -- Start of processing for Get_Current_Value_Condition
3342 -- Immediate return, nothing doing, if this is not an object
3344 if Ekind
(Ent
) not in Object_Kind
then
3348 -- Otherwise examine current value
3351 CV
: constant Node_Id
:= Current_Value
(Ent
);
3356 -- If statement. Condition is known true in THEN section, known False
3357 -- in any ELSIF or ELSE part, and unknown outside the IF statement.
3359 if Nkind
(CV
) = N_If_Statement
then
3361 -- Before start of IF statement
3363 if Loc
< Sloc
(CV
) then
3366 -- After end of IF statement
3368 elsif Loc
>= Sloc
(CV
) + Text_Ptr
(UI_To_Int
(End_Span
(CV
))) then
3372 -- At this stage we know that we are within the IF statement, but
3373 -- unfortunately, the tree does not record the SLOC of the ELSE so
3374 -- we cannot use a simple SLOC comparison to distinguish between
3375 -- the then/else statements, so we have to climb the tree.
3382 while Parent
(N
) /= CV
loop
3385 -- If we fall off the top of the tree, then that's odd, but
3386 -- perhaps it could occur in some error situation, and the
3387 -- safest response is simply to assume that the outcome of
3388 -- the condition is unknown. No point in bombing during an
3389 -- attempt to optimize things.
3396 -- Now we have N pointing to a node whose parent is the IF
3397 -- statement in question, so now we can tell if we are within
3398 -- the THEN statements.
3400 if Is_List_Member
(N
)
3401 and then List_Containing
(N
) = Then_Statements
(CV
)
3405 -- If the variable reference does not come from source, we
3406 -- cannot reliably tell whether it appears in the else part.
3407 -- In particular, if it appears in generated code for a node
3408 -- that requires finalization, it may be attached to a list
3409 -- that has not been yet inserted into the code. For now,
3410 -- treat it as unknown.
3412 elsif not Comes_From_Source
(N
) then
3415 -- Otherwise we must be in ELSIF or ELSE part
3422 -- ELSIF part. Condition is known true within the referenced
3423 -- ELSIF, known False in any subsequent ELSIF or ELSE part,
3424 -- and unknown before the ELSE part or after the IF statement.
3426 elsif Nkind
(CV
) = N_Elsif_Part
then
3428 -- if the Elsif_Part had condition_actions, the elsif has been
3429 -- rewritten as a nested if, and the original elsif_part is
3430 -- detached from the tree, so there is no way to obtain useful
3431 -- information on the current value of the variable.
3432 -- Can this be improved ???
3434 if No
(Parent
(CV
)) then
3440 -- If the tree has been otherwise rewritten there is nothing
3441 -- else to be done either.
3443 if Nkind
(Stm
) /= N_If_Statement
then
3447 -- Before start of ELSIF part
3449 if Loc
< Sloc
(CV
) then
3452 -- After end of IF statement
3454 elsif Loc
>= Sloc
(Stm
) +
3455 Text_Ptr
(UI_To_Int
(End_Span
(Stm
)))
3460 -- Again we lack the SLOC of the ELSE, so we need to climb the
3461 -- tree to see if we are within the ELSIF part in question.
3468 while Parent
(N
) /= Stm
loop
3471 -- If we fall off the top of the tree, then that's odd, but
3472 -- perhaps it could occur in some error situation, and the
3473 -- safest response is simply to assume that the outcome of
3474 -- the condition is unknown. No point in bombing during an
3475 -- attempt to optimize things.
3482 -- Now we have N pointing to a node whose parent is the IF
3483 -- statement in question, so see if is the ELSIF part we want.
3484 -- the THEN statements.
3489 -- Otherwise we must be in subsequent ELSIF or ELSE part
3496 -- Iteration scheme of while loop. The condition is known to be
3497 -- true within the body of the loop.
3499 elsif Nkind
(CV
) = N_Iteration_Scheme
then
3501 Loop_Stmt
: constant Node_Id
:= Parent
(CV
);
3504 -- Before start of body of loop
3506 if Loc
< Sloc
(Loop_Stmt
) then
3509 -- After end of LOOP statement
3511 elsif Loc
>= Sloc
(End_Label
(Loop_Stmt
)) then
3514 -- We are within the body of the loop
3521 -- All other cases of Current_Value settings
3527 -- If we fall through here, then we have a reportable condition, Sens
3528 -- is True if the condition is true and False if it needs inverting.
3530 Process_Current_Value_Condition
(Condition
(CV
), Sens
);
3532 end Get_Current_Value_Condition
;
3534 ---------------------
3535 -- Get_Stream_Size --
3536 ---------------------
3538 function Get_Stream_Size
(E
: Entity_Id
) return Uint
is
3540 -- If we have a Stream_Size clause for this type use it
3542 if Has_Stream_Size_Clause
(E
) then
3543 return Static_Integer
(Expression
(Stream_Size_Clause
(E
)));
3545 -- Otherwise the Stream_Size if the size of the type
3550 end Get_Stream_Size
;
3552 ---------------------------
3553 -- Has_Access_Constraint --
3554 ---------------------------
3556 function Has_Access_Constraint
(E
: Entity_Id
) return Boolean is
3558 T
: constant Entity_Id
:= Etype
(E
);
3561 if Has_Per_Object_Constraint
(E
) and then Has_Discriminants
(T
) then
3562 Disc
:= First_Discriminant
(T
);
3563 while Present
(Disc
) loop
3564 if Is_Access_Type
(Etype
(Disc
)) then
3568 Next_Discriminant
(Disc
);
3575 end Has_Access_Constraint
;
3577 -----------------------------------------------------
3578 -- Has_Annotate_Pragma_For_External_Axiomatization --
3579 -----------------------------------------------------
3581 function Has_Annotate_Pragma_For_External_Axiomatization
3582 (E
: Entity_Id
) return Boolean
3584 function Is_Annotate_Pragma_For_External_Axiomatization
3585 (N
: Node_Id
) return Boolean;
3586 -- Returns whether N is
3587 -- pragma Annotate (GNATprove, External_Axiomatization);
3589 ----------------------------------------------------
3590 -- Is_Annotate_Pragma_For_External_Axiomatization --
3591 ----------------------------------------------------
3593 -- The general form of pragma Annotate is
3595 -- pragma Annotate (IDENTIFIER [, IDENTIFIER {, ARG}]);
3596 -- ARG ::= NAME | EXPRESSION
3598 -- The first two arguments are by convention intended to refer to an
3599 -- external tool and a tool-specific function. These arguments are
3602 -- The following is used to annotate a package specification which
3603 -- GNATprove should treat specially, because the axiomatization of
3604 -- this unit is given by the user instead of being automatically
3607 -- pragma Annotate (GNATprove, External_Axiomatization);
3609 function Is_Annotate_Pragma_For_External_Axiomatization
3610 (N
: Node_Id
) return Boolean
3612 Name_GNATprove
: constant String :=
3614 Name_External_Axiomatization
: constant String :=
3615 "external_axiomatization";
3619 if Nkind
(N
) = N_Pragma
3620 and then Get_Pragma_Id
(Pragma_Name
(N
)) = Pragma_Annotate
3621 and then List_Length
(Pragma_Argument_Associations
(N
)) = 2
3624 Arg1
: constant Node_Id
:=
3625 First
(Pragma_Argument_Associations
(N
));
3626 Arg2
: constant Node_Id
:= Next
(Arg1
);
3631 -- Fill in Name_Buffer with Name_GNATprove first, and then with
3632 -- Name_External_Axiomatization so that Name_Find returns the
3633 -- corresponding name. This takes care of all possible casings.
3636 Add_Str_To_Name_Buffer
(Name_GNATprove
);
3640 Add_Str_To_Name_Buffer
(Name_External_Axiomatization
);
3643 return Chars
(Get_Pragma_Arg
(Arg1
)) = Nam1
3645 Chars
(Get_Pragma_Arg
(Arg2
)) = Nam2
;
3651 end Is_Annotate_Pragma_For_External_Axiomatization
;
3656 Vis_Decls
: List_Id
;
3659 -- Start of processing for Has_Annotate_Pragma_For_External_Axiomatization
3662 if Nkind
(Parent
(E
)) = N_Defining_Program_Unit_Name
then
3663 Decl
:= Parent
(Parent
(E
));
3668 Vis_Decls
:= Visible_Declarations
(Decl
);
3670 N
:= First
(Vis_Decls
);
3671 while Present
(N
) loop
3673 -- Skip declarations generated by the frontend. Skip all pragmas
3674 -- that are not the desired Annotate pragma. Stop the search on
3675 -- the first non-pragma source declaration.
3677 if Comes_From_Source
(N
) then
3678 if Nkind
(N
) = N_Pragma
then
3679 if Is_Annotate_Pragma_For_External_Axiomatization
(N
) then
3691 end Has_Annotate_Pragma_For_External_Axiomatization
;
3693 --------------------
3694 -- Homonym_Number --
3695 --------------------
3697 function Homonym_Number
(Subp
: Entity_Id
) return Nat
is
3703 Hom
:= Homonym
(Subp
);
3704 while Present
(Hom
) loop
3705 if Scope
(Hom
) = Scope
(Subp
) then
3709 Hom
:= Homonym
(Hom
);
3715 -----------------------------------
3716 -- In_Library_Level_Package_Body --
3717 -----------------------------------
3719 function In_Library_Level_Package_Body
(Id
: Entity_Id
) return Boolean is
3721 -- First determine whether the entity appears at the library level, then
3722 -- look at the containing unit.
3724 if Is_Library_Level_Entity
(Id
) then
3726 Container
: constant Node_Id
:= Cunit
(Get_Source_Unit
(Id
));
3729 return Nkind
(Unit
(Container
)) = N_Package_Body
;
3734 end In_Library_Level_Package_Body
;
3736 ------------------------------
3737 -- In_Unconditional_Context --
3738 ------------------------------
3740 function In_Unconditional_Context
(Node
: Node_Id
) return Boolean is
3745 while Present
(P
) loop
3747 when N_Subprogram_Body
=>
3750 when N_If_Statement
=>
3753 when N_Loop_Statement
=>
3756 when N_Case_Statement
=>
3765 end In_Unconditional_Context
;
3771 procedure Insert_Action
(Assoc_Node
: Node_Id
; Ins_Action
: Node_Id
) is
3773 if Present
(Ins_Action
) then
3774 Insert_Actions
(Assoc_Node
, New_List
(Ins_Action
));
3778 -- Version with check(s) suppressed
3780 procedure Insert_Action
3781 (Assoc_Node
: Node_Id
; Ins_Action
: Node_Id
; Suppress
: Check_Id
)
3784 Insert_Actions
(Assoc_Node
, New_List
(Ins_Action
), Suppress
);
3787 -------------------------
3788 -- Insert_Action_After --
3789 -------------------------
3791 procedure Insert_Action_After
3792 (Assoc_Node
: Node_Id
;
3793 Ins_Action
: Node_Id
)
3796 Insert_Actions_After
(Assoc_Node
, New_List
(Ins_Action
));
3797 end Insert_Action_After
;
3799 --------------------
3800 -- Insert_Actions --
3801 --------------------
3803 procedure Insert_Actions
(Assoc_Node
: Node_Id
; Ins_Actions
: List_Id
) is
3807 Wrapped_Node
: Node_Id
:= Empty
;
3810 if No
(Ins_Actions
) or else Is_Empty_List
(Ins_Actions
) then
3814 -- Ignore insert of actions from inside default expression (or other
3815 -- similar "spec expression") in the special spec-expression analyze
3816 -- mode. Any insertions at this point have no relevance, since we are
3817 -- only doing the analyze to freeze the types of any static expressions.
3818 -- See section "Handling of Default Expressions" in the spec of package
3819 -- Sem for further details.
3821 if In_Spec_Expression
then
3825 -- If the action derives from stuff inside a record, then the actions
3826 -- are attached to the current scope, to be inserted and analyzed on
3827 -- exit from the scope. The reason for this is that we may also be
3828 -- generating freeze actions at the same time, and they must eventually
3829 -- be elaborated in the correct order.
3831 if Is_Record_Type
(Current_Scope
)
3832 and then not Is_Frozen
(Current_Scope
)
3834 if No
(Scope_Stack
.Table
3835 (Scope_Stack
.Last
).Pending_Freeze_Actions
)
3837 Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
:=
3842 Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
);
3848 -- We now intend to climb up the tree to find the right point to
3849 -- insert the actions. We start at Assoc_Node, unless this node is a
3850 -- subexpression in which case we start with its parent. We do this for
3851 -- two reasons. First it speeds things up. Second, if Assoc_Node is
3852 -- itself one of the special nodes like N_And_Then, then we assume that
3853 -- an initial request to insert actions for such a node does not expect
3854 -- the actions to get deposited in the node for later handling when the
3855 -- node is expanded, since clearly the node is being dealt with by the
3856 -- caller. Note that in the subexpression case, N is always the child we
3859 -- N_Raise_xxx_Error is an annoying special case, it is a statement
3860 -- if it has type Standard_Void_Type, and a subexpression otherwise.
3861 -- Procedure calls, and similarly procedure attribute references, are
3864 if Nkind
(Assoc_Node
) in N_Subexpr
3865 and then (Nkind
(Assoc_Node
) not in N_Raise_xxx_Error
3866 or else Etype
(Assoc_Node
) /= Standard_Void_Type
)
3867 and then Nkind
(Assoc_Node
) /= N_Procedure_Call_Statement
3868 and then (Nkind
(Assoc_Node
) /= N_Attribute_Reference
3869 or else not Is_Procedure_Attribute_Name
3870 (Attribute_Name
(Assoc_Node
)))
3873 P
:= Parent
(Assoc_Node
);
3875 -- Non-subexpression case. Note that N is initially Empty in this case
3876 -- (N is only guaranteed Non-Empty in the subexpr case).
3883 -- Capture root of the transient scope
3885 if Scope_Is_Transient
then
3886 Wrapped_Node
:= Node_To_Be_Wrapped
;
3890 pragma Assert
(Present
(P
));
3892 -- Make sure that inserted actions stay in the transient scope
3894 if Present
(Wrapped_Node
) and then N
= Wrapped_Node
then
3895 Store_Before_Actions_In_Scope
(Ins_Actions
);
3901 -- Case of right operand of AND THEN or OR ELSE. Put the actions
3902 -- in the Actions field of the right operand. They will be moved
3903 -- out further when the AND THEN or OR ELSE operator is expanded.
3904 -- Nothing special needs to be done for the left operand since
3905 -- in that case the actions are executed unconditionally.
3907 when N_Short_Circuit
=>
3908 if N
= Right_Opnd
(P
) then
3910 -- We are now going to either append the actions to the
3911 -- actions field of the short-circuit operation. We will
3912 -- also analyze the actions now.
3914 -- This analysis is really too early, the proper thing would
3915 -- be to just park them there now, and only analyze them if
3916 -- we find we really need them, and to it at the proper
3917 -- final insertion point. However attempting to this proved
3918 -- tricky, so for now we just kill current values before and
3919 -- after the analyze call to make sure we avoid peculiar
3920 -- optimizations from this out of order insertion.
3922 Kill_Current_Values
;
3924 -- If P has already been expanded, we can't park new actions
3925 -- on it, so we need to expand them immediately, introducing
3926 -- an Expression_With_Actions. N can't be an expression
3927 -- with actions, or else then the actions would have been
3928 -- inserted at an inner level.
3930 if Analyzed
(P
) then
3931 pragma Assert
(Nkind
(N
) /= N_Expression_With_Actions
);
3933 Make_Expression_With_Actions
(Sloc
(N
),
3934 Actions
=> Ins_Actions
,
3935 Expression
=> Relocate_Node
(N
)));
3936 Analyze_And_Resolve
(N
);
3938 elsif Present
(Actions
(P
)) then
3939 Insert_List_After_And_Analyze
3940 (Last
(Actions
(P
)), Ins_Actions
);
3942 Set_Actions
(P
, Ins_Actions
);
3943 Analyze_List
(Actions
(P
));
3946 Kill_Current_Values
;
3951 -- Then or Else dependent expression of an if expression. Add
3952 -- actions to Then_Actions or Else_Actions field as appropriate.
3953 -- The actions will be moved further out when the if is expanded.
3955 when N_If_Expression
=>
3957 ThenX
: constant Node_Id
:= Next
(First
(Expressions
(P
)));
3958 ElseX
: constant Node_Id
:= Next
(ThenX
);
3961 -- If the enclosing expression is already analyzed, as
3962 -- is the case for nested elaboration checks, insert the
3963 -- conditional further out.
3965 if Analyzed
(P
) then
3968 -- Actions belong to the then expression, temporarily place
3969 -- them as Then_Actions of the if expression. They will be
3970 -- moved to the proper place later when the if expression
3973 elsif N
= ThenX
then
3974 if Present
(Then_Actions
(P
)) then
3975 Insert_List_After_And_Analyze
3976 (Last
(Then_Actions
(P
)), Ins_Actions
);
3978 Set_Then_Actions
(P
, Ins_Actions
);
3979 Analyze_List
(Then_Actions
(P
));
3984 -- Actions belong to the else expression, temporarily place
3985 -- them as Else_Actions of the if expression. They will be
3986 -- moved to the proper place later when the if expression
3989 elsif N
= ElseX
then
3990 if Present
(Else_Actions
(P
)) then
3991 Insert_List_After_And_Analyze
3992 (Last
(Else_Actions
(P
)), Ins_Actions
);
3994 Set_Else_Actions
(P
, Ins_Actions
);
3995 Analyze_List
(Else_Actions
(P
));
4000 -- Actions belong to the condition. In this case they are
4001 -- unconditionally executed, and so we can continue the
4002 -- search for the proper insert point.
4009 -- Alternative of case expression, we place the action in the
4010 -- Actions field of the case expression alternative, this will
4011 -- be handled when the case expression is expanded.
4013 when N_Case_Expression_Alternative
=>
4014 if Present
(Actions
(P
)) then
4015 Insert_List_After_And_Analyze
4016 (Last
(Actions
(P
)), Ins_Actions
);
4018 Set_Actions
(P
, Ins_Actions
);
4019 Analyze_List
(Actions
(P
));
4024 -- Case of appearing within an Expressions_With_Actions node. When
4025 -- the new actions come from the expression of the expression with
4026 -- actions, they must be added to the existing actions. The other
4027 -- alternative is when the new actions are related to one of the
4028 -- existing actions of the expression with actions, and should
4029 -- never reach here: if actions are inserted on a statement
4030 -- within the Actions of an expression with actions, or on some
4031 -- sub-expression of such a statement, then the outermost proper
4032 -- insertion point is right before the statement, and we should
4033 -- never climb up as far as the N_Expression_With_Actions itself.
4035 when N_Expression_With_Actions
=>
4036 if N
= Expression
(P
) then
4037 if Is_Empty_List
(Actions
(P
)) then
4038 Append_List_To
(Actions
(P
), Ins_Actions
);
4039 Analyze_List
(Actions
(P
));
4041 Insert_List_After_And_Analyze
4042 (Last
(Actions
(P
)), Ins_Actions
);
4048 raise Program_Error
;
4051 -- Case of appearing in the condition of a while expression or
4052 -- elsif. We insert the actions into the Condition_Actions field.
4053 -- They will be moved further out when the while loop or elsif
4056 when N_Iteration_Scheme |
4059 if N
= Condition
(P
) then
4060 if Present
(Condition_Actions
(P
)) then
4061 Insert_List_After_And_Analyze
4062 (Last
(Condition_Actions
(P
)), Ins_Actions
);
4064 Set_Condition_Actions
(P
, Ins_Actions
);
4066 -- Set the parent of the insert actions explicitly. This
4067 -- is not a syntactic field, but we need the parent field
4068 -- set, in particular so that freeze can understand that
4069 -- it is dealing with condition actions, and properly
4070 -- insert the freezing actions.
4072 Set_Parent
(Ins_Actions
, P
);
4073 Analyze_List
(Condition_Actions
(P
));
4078 -- Iteration scheme located in a transient scope
4080 elsif Nkind
(P
) = N_Iteration_Scheme
4081 and then Present
(Wrapped_Node
)
4083 -- If the enclosing iterator loop is marked as requiring the
4084 -- secondary stack then the actions must be inserted in the
4088 (Find_Enclosing_Iterator_Loop
(Current_Scope
))
4090 Store_Before_Actions_In_Scope
(Ins_Actions
);
4095 -- Statements, declarations, pragmas, representation clauses
4100 N_Procedure_Call_Statement |
4101 N_Statement_Other_Than_Procedure_Call |
4107 -- Representation_Clause
4110 N_Attribute_Definition_Clause |
4111 N_Enumeration_Representation_Clause |
4112 N_Record_Representation_Clause |
4116 N_Abstract_Subprogram_Declaration |
4118 N_Exception_Declaration |
4119 N_Exception_Renaming_Declaration |
4120 N_Expression_Function |
4121 N_Formal_Abstract_Subprogram_Declaration |
4122 N_Formal_Concrete_Subprogram_Declaration |
4123 N_Formal_Object_Declaration |
4124 N_Formal_Type_Declaration |
4125 N_Full_Type_Declaration |
4126 N_Function_Instantiation |
4127 N_Generic_Function_Renaming_Declaration |
4128 N_Generic_Package_Declaration |
4129 N_Generic_Package_Renaming_Declaration |
4130 N_Generic_Procedure_Renaming_Declaration |
4131 N_Generic_Subprogram_Declaration |
4132 N_Implicit_Label_Declaration |
4133 N_Incomplete_Type_Declaration |
4134 N_Number_Declaration |
4135 N_Object_Declaration |
4136 N_Object_Renaming_Declaration |
4138 N_Package_Body_Stub |
4139 N_Package_Declaration |
4140 N_Package_Instantiation |
4141 N_Package_Renaming_Declaration |
4142 N_Private_Extension_Declaration |
4143 N_Private_Type_Declaration |
4144 N_Procedure_Instantiation |
4146 N_Protected_Body_Stub |
4147 N_Protected_Type_Declaration |
4148 N_Single_Task_Declaration |
4150 N_Subprogram_Body_Stub |
4151 N_Subprogram_Declaration |
4152 N_Subprogram_Renaming_Declaration |
4153 N_Subtype_Declaration |
4156 N_Task_Type_Declaration |
4158 -- Use clauses can appear in lists of declarations
4160 N_Use_Package_Clause |
4163 -- Freeze entity behaves like a declaration or statement
4166 N_Freeze_Generic_Entity
4168 -- Do not insert here if the item is not a list member (this
4169 -- happens for example with a triggering statement, and the
4170 -- proper approach is to insert before the entire select).
4172 if not Is_List_Member
(P
) then
4175 -- Do not insert if parent of P is an N_Component_Association
4176 -- node (i.e. we are in the context of an N_Aggregate or
4177 -- N_Extension_Aggregate node. In this case we want to insert
4178 -- before the entire aggregate.
4180 elsif Nkind
(Parent
(P
)) = N_Component_Association
then
4183 -- Do not insert if the parent of P is either an N_Variant node
4184 -- or an N_Record_Definition node, meaning in either case that
4185 -- P is a member of a component list, and that therefore the
4186 -- actions should be inserted outside the complete record
4189 elsif Nkind_In
(Parent
(P
), N_Variant
, N_Record_Definition
) then
4192 -- Do not insert freeze nodes within the loop generated for
4193 -- an aggregate, because they may be elaborated too late for
4194 -- subsequent use in the back end: within a package spec the
4195 -- loop is part of the elaboration procedure and is only
4196 -- elaborated during the second pass.
4198 -- If the loop comes from source, or the entity is local to the
4199 -- loop itself it must remain within.
4201 elsif Nkind
(Parent
(P
)) = N_Loop_Statement
4202 and then not Comes_From_Source
(Parent
(P
))
4203 and then Nkind
(First
(Ins_Actions
)) = N_Freeze_Entity
4205 Scope
(Entity
(First
(Ins_Actions
))) /= Current_Scope
4209 -- Otherwise we can go ahead and do the insertion
4211 elsif P
= Wrapped_Node
then
4212 Store_Before_Actions_In_Scope
(Ins_Actions
);
4216 Insert_List_Before_And_Analyze
(P
, Ins_Actions
);
4220 -- A special case, N_Raise_xxx_Error can act either as a statement
4221 -- or a subexpression. We tell the difference by looking at the
4222 -- Etype. It is set to Standard_Void_Type in the statement case.
4225 N_Raise_xxx_Error
=>
4226 if Etype
(P
) = Standard_Void_Type
then
4227 if P
= Wrapped_Node
then
4228 Store_Before_Actions_In_Scope
(Ins_Actions
);
4230 Insert_List_Before_And_Analyze
(P
, Ins_Actions
);
4235 -- In the subexpression case, keep climbing
4241 -- If a component association appears within a loop created for
4242 -- an array aggregate, attach the actions to the association so
4243 -- they can be subsequently inserted within the loop. For other
4244 -- component associations insert outside of the aggregate. For
4245 -- an association that will generate a loop, its Loop_Actions
4246 -- attribute is already initialized (see exp_aggr.adb).
4248 -- The list of loop_actions can in turn generate additional ones,
4249 -- that are inserted before the associated node. If the associated
4250 -- node is outside the aggregate, the new actions are collected
4251 -- at the end of the loop actions, to respect the order in which
4252 -- they are to be elaborated.
4255 N_Component_Association
=>
4256 if Nkind
(Parent
(P
)) = N_Aggregate
4257 and then Present
(Loop_Actions
(P
))
4259 if Is_Empty_List
(Loop_Actions
(P
)) then
4260 Set_Loop_Actions
(P
, Ins_Actions
);
4261 Analyze_List
(Ins_Actions
);
4268 -- Check whether these actions were generated by a
4269 -- declaration that is part of the loop_ actions
4270 -- for the component_association.
4273 while Present
(Decl
) loop
4274 exit when Parent
(Decl
) = P
4275 and then Is_List_Member
(Decl
)
4277 List_Containing
(Decl
) = Loop_Actions
(P
);
4278 Decl
:= Parent
(Decl
);
4281 if Present
(Decl
) then
4282 Insert_List_Before_And_Analyze
4283 (Decl
, Ins_Actions
);
4285 Insert_List_After_And_Analyze
4286 (Last
(Loop_Actions
(P
)), Ins_Actions
);
4297 -- Another special case, an attribute denoting a procedure call
4300 N_Attribute_Reference
=>
4301 if Is_Procedure_Attribute_Name
(Attribute_Name
(P
)) then
4302 if P
= Wrapped_Node
then
4303 Store_Before_Actions_In_Scope
(Ins_Actions
);
4305 Insert_List_Before_And_Analyze
(P
, Ins_Actions
);
4310 -- In the subexpression case, keep climbing
4316 -- A contract node should not belong to the tree
4319 raise Program_Error
;
4321 -- For all other node types, keep climbing tree
4325 N_Accept_Alternative |
4326 N_Access_Definition |
4327 N_Access_Function_Definition |
4328 N_Access_Procedure_Definition |
4329 N_Access_To_Object_Definition |
4332 N_Aspect_Specification |
4334 N_Case_Statement_Alternative |
4335 N_Character_Literal |
4336 N_Compilation_Unit |
4337 N_Compilation_Unit_Aux |
4338 N_Component_Clause |
4339 N_Component_Declaration |
4340 N_Component_Definition |
4342 N_Constrained_Array_Definition |
4343 N_Decimal_Fixed_Point_Definition |
4344 N_Defining_Character_Literal |
4345 N_Defining_Identifier |
4346 N_Defining_Operator_Symbol |
4347 N_Defining_Program_Unit_Name |
4348 N_Delay_Alternative |
4349 N_Delta_Constraint |
4350 N_Derived_Type_Definition |
4352 N_Digits_Constraint |
4353 N_Discriminant_Association |
4354 N_Discriminant_Specification |
4356 N_Entry_Body_Formal_Part |
4357 N_Entry_Call_Alternative |
4358 N_Entry_Declaration |
4359 N_Entry_Index_Specification |
4360 N_Enumeration_Type_Definition |
4362 N_Exception_Handler |
4364 N_Explicit_Dereference |
4365 N_Extension_Aggregate |
4366 N_Floating_Point_Definition |
4367 N_Formal_Decimal_Fixed_Point_Definition |
4368 N_Formal_Derived_Type_Definition |
4369 N_Formal_Discrete_Type_Definition |
4370 N_Formal_Floating_Point_Definition |
4371 N_Formal_Modular_Type_Definition |
4372 N_Formal_Ordinary_Fixed_Point_Definition |
4373 N_Formal_Package_Declaration |
4374 N_Formal_Private_Type_Definition |
4375 N_Formal_Incomplete_Type_Definition |
4376 N_Formal_Signed_Integer_Type_Definition |
4378 N_Function_Specification |
4379 N_Generic_Association |
4380 N_Handled_Sequence_Of_Statements |
4383 N_Index_Or_Discriminant_Constraint |
4384 N_Indexed_Component |
4386 N_Iterator_Specification |
4389 N_Loop_Parameter_Specification |
4391 N_Modular_Type_Definition |
4417 N_Op_Shift_Right_Arithmetic |
4421 N_Ordinary_Fixed_Point_Definition |
4423 N_Package_Specification |
4424 N_Parameter_Association |
4425 N_Parameter_Specification |
4426 N_Pop_Constraint_Error_Label |
4427 N_Pop_Program_Error_Label |
4428 N_Pop_Storage_Error_Label |
4429 N_Pragma_Argument_Association |
4430 N_Procedure_Specification |
4431 N_Protected_Definition |
4432 N_Push_Constraint_Error_Label |
4433 N_Push_Program_Error_Label |
4434 N_Push_Storage_Error_Label |
4435 N_Qualified_Expression |
4436 N_Quantified_Expression |
4437 N_Raise_Expression |
4439 N_Range_Constraint |
4441 N_Real_Range_Specification |
4442 N_Record_Definition |
4444 N_SCIL_Dispatch_Table_Tag_Init |
4445 N_SCIL_Dispatching_Call |
4446 N_SCIL_Membership_Test |
4447 N_Selected_Component |
4448 N_Signed_Integer_Type_Definition |
4449 N_Single_Protected_Declaration |
4452 N_Subtype_Indication |
4455 N_Terminate_Alternative |
4456 N_Triggering_Alternative |
4458 N_Unchecked_Expression |
4459 N_Unchecked_Type_Conversion |
4460 N_Unconstrained_Array_Definition |
4465 N_Validate_Unchecked_Conversion |
4472 -- If we fall through above tests, keep climbing tree
4476 if Nkind
(Parent
(N
)) = N_Subunit
then
4478 -- This is the proper body corresponding to a stub. Insertion must
4479 -- be done at the point of the stub, which is in the declarative
4480 -- part of the parent unit.
4482 P
:= Corresponding_Stub
(Parent
(N
));
4490 -- Version with check(s) suppressed
4492 procedure Insert_Actions
4493 (Assoc_Node
: Node_Id
;
4494 Ins_Actions
: List_Id
;
4495 Suppress
: Check_Id
)
4498 if Suppress
= All_Checks
then
4500 Sva
: constant Suppress_Array
:= Scope_Suppress
.Suppress
;
4502 Scope_Suppress
.Suppress
:= (others => True);
4503 Insert_Actions
(Assoc_Node
, Ins_Actions
);
4504 Scope_Suppress
.Suppress
:= Sva
;
4509 Svg
: constant Boolean := Scope_Suppress
.Suppress
(Suppress
);
4511 Scope_Suppress
.Suppress
(Suppress
) := True;
4512 Insert_Actions
(Assoc_Node
, Ins_Actions
);
4513 Scope_Suppress
.Suppress
(Suppress
) := Svg
;
4518 --------------------------
4519 -- Insert_Actions_After --
4520 --------------------------
4522 procedure Insert_Actions_After
4523 (Assoc_Node
: Node_Id
;
4524 Ins_Actions
: List_Id
)
4527 if Scope_Is_Transient
and then Assoc_Node
= Node_To_Be_Wrapped
then
4528 Store_After_Actions_In_Scope
(Ins_Actions
);
4530 Insert_List_After_And_Analyze
(Assoc_Node
, Ins_Actions
);
4532 end Insert_Actions_After
;
4534 ------------------------
4535 -- Insert_Declaration --
4536 ------------------------
4538 procedure Insert_Declaration
(N
: Node_Id
; Decl
: Node_Id
) is
4542 pragma Assert
(Nkind
(N
) in N_Subexpr
);
4544 -- Climb until we find a procedure or a package
4548 pragma Assert
(Present
(Parent
(P
)));
4551 if Is_List_Member
(P
) then
4552 exit when Nkind_In
(Parent
(P
), N_Package_Specification
,
4555 -- Special handling for handled sequence of statements, we must
4556 -- insert in the statements not the exception handlers!
4558 if Nkind
(Parent
(P
)) = N_Handled_Sequence_Of_Statements
then
4559 P
:= First
(Statements
(Parent
(P
)));
4565 -- Now do the insertion
4567 Insert_Before
(P
, Decl
);
4569 end Insert_Declaration
;
4571 ---------------------------------
4572 -- Insert_Library_Level_Action --
4573 ---------------------------------
4575 procedure Insert_Library_Level_Action
(N
: Node_Id
) is
4576 Aux
: constant Node_Id
:= Aux_Decls_Node
(Cunit
(Main_Unit
));
4579 Push_Scope
(Cunit_Entity
(Main_Unit
));
4580 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
4582 if No
(Actions
(Aux
)) then
4583 Set_Actions
(Aux
, New_List
(N
));
4585 Append
(N
, Actions
(Aux
));
4590 end Insert_Library_Level_Action
;
4592 ----------------------------------
4593 -- Insert_Library_Level_Actions --
4594 ----------------------------------
4596 procedure Insert_Library_Level_Actions
(L
: List_Id
) is
4597 Aux
: constant Node_Id
:= Aux_Decls_Node
(Cunit
(Main_Unit
));
4600 if Is_Non_Empty_List
(L
) then
4601 Push_Scope
(Cunit_Entity
(Main_Unit
));
4602 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
4604 if No
(Actions
(Aux
)) then
4605 Set_Actions
(Aux
, L
);
4608 Insert_List_After_And_Analyze
(Last
(Actions
(Aux
)), L
);
4613 end Insert_Library_Level_Actions
;
4615 ----------------------
4616 -- Inside_Init_Proc --
4617 ----------------------
4619 function Inside_Init_Proc
return Boolean is
4624 while Present
(S
) and then S
/= Standard_Standard
loop
4625 if Is_Init_Proc
(S
) then
4633 end Inside_Init_Proc
;
4635 ----------------------------
4636 -- Is_All_Null_Statements --
4637 ----------------------------
4639 function Is_All_Null_Statements
(L
: List_Id
) return Boolean is
4644 while Present
(Stm
) loop
4645 if Nkind
(Stm
) /= N_Null_Statement
then
4653 end Is_All_Null_Statements
;
4655 --------------------------------------------------
4656 -- Is_Displacement_Of_Object_Or_Function_Result --
4657 --------------------------------------------------
4659 function Is_Displacement_Of_Object_Or_Function_Result
4660 (Obj_Id
: Entity_Id
) return Boolean
4662 function Is_Controlled_Function_Call
(N
: Node_Id
) return Boolean;
4663 -- Determine if particular node denotes a controlled function call. The
4664 -- call may have been heavily expanded.
4666 function Is_Displace_Call
(N
: Node_Id
) return Boolean;
4667 -- Determine whether a particular node is a call to Ada.Tags.Displace.
4668 -- The call might be nested within other actions such as conversions.
4670 function Is_Source_Object
(N
: Node_Id
) return Boolean;
4671 -- Determine whether a particular node denotes a source object
4673 ---------------------------------
4674 -- Is_Controlled_Function_Call --
4675 ---------------------------------
4677 function Is_Controlled_Function_Call
(N
: Node_Id
) return Boolean is
4678 Expr
: Node_Id
:= Original_Node
(N
);
4681 if Nkind
(Expr
) = N_Function_Call
then
4682 Expr
:= Name
(Expr
);
4684 -- When a function call appears in Object.Operation format, the
4685 -- original representation has two possible forms depending on the
4686 -- availability of actual parameters:
4688 -- Obj.Func_Call N_Selected_Component
4689 -- Obj.Func_Call (Param) N_Indexed_Component
4692 if Nkind
(Expr
) = N_Indexed_Component
then
4693 Expr
:= Prefix
(Expr
);
4696 if Nkind
(Expr
) = N_Selected_Component
then
4697 Expr
:= Selector_Name
(Expr
);
4702 Nkind_In
(Expr
, N_Expanded_Name
, N_Identifier
)
4703 and then Ekind
(Entity
(Expr
)) = E_Function
4704 and then Needs_Finalization
(Etype
(Entity
(Expr
)));
4705 end Is_Controlled_Function_Call
;
4707 ----------------------
4708 -- Is_Displace_Call --
4709 ----------------------
4711 function Is_Displace_Call
(N
: Node_Id
) return Boolean is
4712 Call
: Node_Id
:= N
;
4715 -- Strip various actions which may precede a call to Displace
4718 if Nkind
(Call
) = N_Explicit_Dereference
then
4719 Call
:= Prefix
(Call
);
4721 elsif Nkind_In
(Call
, N_Type_Conversion
,
4722 N_Unchecked_Type_Conversion
)
4724 Call
:= Expression
(Call
);
4733 and then Nkind
(Call
) = N_Function_Call
4734 and then Is_RTE
(Entity
(Name
(Call
)), RE_Displace
);
4735 end Is_Displace_Call
;
4737 ----------------------
4738 -- Is_Source_Object --
4739 ----------------------
4741 function Is_Source_Object
(N
: Node_Id
) return Boolean is
4745 and then Nkind
(N
) in N_Has_Entity
4746 and then Is_Object
(Entity
(N
))
4747 and then Comes_From_Source
(N
);
4748 end Is_Source_Object
;
4752 Decl
: constant Node_Id
:= Parent
(Obj_Id
);
4753 Obj_Typ
: constant Entity_Id
:= Base_Type
(Etype
(Obj_Id
));
4754 Orig_Decl
: constant Node_Id
:= Original_Node
(Decl
);
4756 -- Start of processing for Is_Displacement_Of_Object_Or_Function_Result
4761 -- Obj : CW_Type := Function_Call (...);
4765 -- Tmp : ... := Function_Call (...)'reference;
4766 -- Obj : CW_Type renames (... Ada.Tags.Displace (Tmp));
4768 -- where the return type of the function and the class-wide type require
4769 -- dispatch table pointer displacement.
4773 -- Obj : CW_Type := Src_Obj;
4777 -- Obj : CW_Type renames (... Ada.Tags.Displace (Src_Obj));
4779 -- where the type of the source object and the class-wide type require
4780 -- dispatch table pointer displacement.
4783 Nkind
(Decl
) = N_Object_Renaming_Declaration
4784 and then Nkind
(Orig_Decl
) = N_Object_Declaration
4785 and then Comes_From_Source
(Orig_Decl
)
4786 and then Is_Class_Wide_Type
(Obj_Typ
)
4787 and then Is_Displace_Call
(Renamed_Object
(Obj_Id
))
4789 (Is_Controlled_Function_Call
(Expression
(Orig_Decl
))
4790 or else Is_Source_Object
(Expression
(Orig_Decl
)));
4791 end Is_Displacement_Of_Object_Or_Function_Result
;
4793 ------------------------------
4794 -- Is_Finalizable_Transient --
4795 ------------------------------
4797 function Is_Finalizable_Transient
4799 Rel_Node
: Node_Id
) return Boolean
4801 Obj_Id
: constant Entity_Id
:= Defining_Identifier
(Decl
);
4802 Obj_Typ
: constant Entity_Id
:= Base_Type
(Etype
(Obj_Id
));
4804 function Initialized_By_Access
(Trans_Id
: Entity_Id
) return Boolean;
4805 -- Determine whether transient object Trans_Id is initialized either
4806 -- by a function call which returns an access type or simply renames
4809 function Initialized_By_Aliased_BIP_Func_Call
4810 (Trans_Id
: Entity_Id
) return Boolean;
4811 -- Determine whether transient object Trans_Id is initialized by a
4812 -- build-in-place function call where the BIPalloc parameter is of
4813 -- value 1 and BIPaccess is not null. This case creates an aliasing
4814 -- between the returned value and the value denoted by BIPaccess.
4817 (Trans_Id
: Entity_Id
;
4818 First_Stmt
: Node_Id
) return Boolean;
4819 -- Determine whether transient object Trans_Id has been renamed or
4820 -- aliased through 'reference in the statement list starting from
4823 function Is_Allocated
(Trans_Id
: Entity_Id
) return Boolean;
4824 -- Determine whether transient object Trans_Id is allocated on the heap
4826 function Is_Iterated_Container
4827 (Trans_Id
: Entity_Id
;
4828 First_Stmt
: Node_Id
) return Boolean;
4829 -- Determine whether transient object Trans_Id denotes a container which
4830 -- is in the process of being iterated in the statement list starting
4833 ---------------------------
4834 -- Initialized_By_Access --
4835 ---------------------------
4837 function Initialized_By_Access
(Trans_Id
: Entity_Id
) return Boolean is
4838 Expr
: constant Node_Id
:= Expression
(Parent
(Trans_Id
));
4843 and then Nkind
(Expr
) /= N_Reference
4844 and then Is_Access_Type
(Etype
(Expr
));
4845 end Initialized_By_Access
;
4847 ------------------------------------------
4848 -- Initialized_By_Aliased_BIP_Func_Call --
4849 ------------------------------------------
4851 function Initialized_By_Aliased_BIP_Func_Call
4852 (Trans_Id
: Entity_Id
) return Boolean
4854 Call
: Node_Id
:= Expression
(Parent
(Trans_Id
));
4857 -- Build-in-place calls usually appear in 'reference format
4859 if Nkind
(Call
) = N_Reference
then
4860 Call
:= Prefix
(Call
);
4863 if Is_Build_In_Place_Function_Call
(Call
) then
4865 Access_Nam
: Name_Id
:= No_Name
;
4866 Access_OK
: Boolean := False;
4868 Alloc_Nam
: Name_Id
:= No_Name
;
4869 Alloc_OK
: Boolean := False;
4871 Func_Id
: Entity_Id
;
4875 -- Examine all parameter associations of the function call
4877 Param
:= First
(Parameter_Associations
(Call
));
4878 while Present
(Param
) loop
4879 if Nkind
(Param
) = N_Parameter_Association
4880 and then Nkind
(Selector_Name
(Param
)) = N_Identifier
4882 Actual
:= Explicit_Actual_Parameter
(Param
);
4883 Formal
:= Selector_Name
(Param
);
4885 -- Construct the names of formals BIPaccess and BIPalloc
4886 -- using the function name retrieved from an arbitrary
4889 if Access_Nam
= No_Name
4890 and then Alloc_Nam
= No_Name
4891 and then Present
(Entity
(Formal
))
4893 Func_Id
:= Scope
(Entity
(Formal
));
4896 New_External_Name
(Chars
(Func_Id
),
4897 BIP_Formal_Suffix
(BIP_Object_Access
));
4900 New_External_Name
(Chars
(Func_Id
),
4901 BIP_Formal_Suffix
(BIP_Alloc_Form
));
4904 -- A match for BIPaccess => Temp has been found
4906 if Chars
(Formal
) = Access_Nam
4907 and then Nkind
(Actual
) /= N_Null
4912 -- A match for BIPalloc => 1 has been found
4914 if Chars
(Formal
) = Alloc_Nam
4915 and then Nkind
(Actual
) = N_Integer_Literal
4916 and then Intval
(Actual
) = Uint_1
4925 return Access_OK
and Alloc_OK
;
4930 end Initialized_By_Aliased_BIP_Func_Call
;
4937 (Trans_Id
: Entity_Id
;
4938 First_Stmt
: Node_Id
) return Boolean
4940 function Find_Renamed_Object
(Ren_Decl
: Node_Id
) return Entity_Id
;
4941 -- Given an object renaming declaration, retrieve the entity of the
4942 -- renamed name. Return Empty if the renamed name is anything other
4943 -- than a variable or a constant.
4945 -------------------------
4946 -- Find_Renamed_Object --
4947 -------------------------
4949 function Find_Renamed_Object
(Ren_Decl
: Node_Id
) return Entity_Id
is
4950 Ren_Obj
: Node_Id
:= Empty
;
4952 function Find_Object
(N
: Node_Id
) return Traverse_Result
;
4953 -- Try to detect an object which is either a constant or a
4960 function Find_Object
(N
: Node_Id
) return Traverse_Result
is
4962 -- Stop the search once a constant or a variable has been
4965 if Nkind
(N
) = N_Identifier
4966 and then Present
(Entity
(N
))
4967 and then Ekind_In
(Entity
(N
), E_Constant
, E_Variable
)
4969 Ren_Obj
:= Entity
(N
);
4976 procedure Search
is new Traverse_Proc
(Find_Object
);
4980 Typ
: constant Entity_Id
:= Etype
(Defining_Identifier
(Ren_Decl
));
4982 -- Start of processing for Find_Renamed_Object
4985 -- Actions related to dispatching calls may appear as renamings of
4986 -- tags. Do not process this type of renaming because it does not
4987 -- use the actual value of the object.
4989 if not Is_RTE
(Typ
, RE_Tag_Ptr
) then
4990 Search
(Name
(Ren_Decl
));
4994 end Find_Renamed_Object
;
4999 Ren_Obj
: Entity_Id
;
5002 -- Start of processing for Is_Aliased
5005 -- A controlled transient object is not considered aliased when it
5006 -- appears inside an expression_with_actions node even when there are
5007 -- explicit aliases of it:
5010 -- Trans_Id : Ctrl_Typ ...; -- controlled transient object
5011 -- Alias : ... := Trans_Id; -- object is aliased
5012 -- Val : constant Boolean :=
5013 -- ... Alias ...; -- aliasing ends
5014 -- <finalize Trans_Id> -- object safe to finalize
5017 -- Expansion ensures that all aliases are encapsulated in the actions
5018 -- list and do not leak to the expression by forcing the evaluation
5019 -- of the expression.
5021 if Nkind
(Rel_Node
) = N_Expression_With_Actions
then
5024 -- Otherwise examine the statements after the controlled transient
5025 -- object and look for various forms of aliasing.
5029 while Present
(Stmt
) loop
5030 if Nkind
(Stmt
) = N_Object_Declaration
then
5031 Expr
:= Expression
(Stmt
);
5033 -- Aliasing of the form:
5034 -- Obj : ... := Trans_Id'reference;
5037 and then Nkind
(Expr
) = N_Reference
5038 and then Nkind
(Prefix
(Expr
)) = N_Identifier
5039 and then Entity
(Prefix
(Expr
)) = Trans_Id
5044 elsif Nkind
(Stmt
) = N_Object_Renaming_Declaration
then
5045 Ren_Obj
:= Find_Renamed_Object
(Stmt
);
5047 -- Aliasing of the form:
5048 -- Obj : ... renames ... Trans_Id ...;
5050 if Present
(Ren_Obj
) and then Ren_Obj
= Trans_Id
then
5066 function Is_Allocated
(Trans_Id
: Entity_Id
) return Boolean is
5067 Expr
: constant Node_Id
:= Expression
(Parent
(Trans_Id
));
5070 Is_Access_Type
(Etype
(Trans_Id
))
5071 and then Present
(Expr
)
5072 and then Nkind
(Expr
) = N_Allocator
;
5075 ---------------------------
5076 -- Is_Iterated_Container --
5077 ---------------------------
5079 function Is_Iterated_Container
5080 (Trans_Id
: Entity_Id
;
5081 First_Stmt
: Node_Id
) return Boolean
5091 -- It is not possible to iterate over containers in non-Ada 2012 code
5093 if Ada_Version
< Ada_2012
then
5097 Typ
:= Etype
(Trans_Id
);
5099 -- Handle access type created for secondary stack use
5101 if Is_Access_Type
(Typ
) then
5102 Typ
:= Designated_Type
(Typ
);
5105 -- Look for aspect Default_Iterator. It may be part of a type
5106 -- declaration for a container, or inherited from a base type
5109 Aspect
:= Find_Value_Of_Aspect
(Typ
, Aspect_Default_Iterator
);
5111 if Present
(Aspect
) then
5112 Iter
:= Entity
(Aspect
);
5114 -- Examine the statements following the container object and
5115 -- look for a call to the default iterate routine where the
5116 -- first parameter is the transient. Such a call appears as:
5118 -- It : Access_To_CW_Iterator :=
5119 -- Iterate (Tran_Id.all, ...)'reference;
5122 while Present
(Stmt
) loop
5124 -- Detect an object declaration which is initialized by a
5125 -- secondary stack function call.
5127 if Nkind
(Stmt
) = N_Object_Declaration
5128 and then Present
(Expression
(Stmt
))
5129 and then Nkind
(Expression
(Stmt
)) = N_Reference
5130 and then Nkind
(Prefix
(Expression
(Stmt
))) = N_Function_Call
5132 Call
:= Prefix
(Expression
(Stmt
));
5134 -- The call must invoke the default iterate routine of
5135 -- the container and the transient object must appear as
5136 -- the first actual parameter. Skip any calls whose names
5137 -- are not entities.
5139 if Is_Entity_Name
(Name
(Call
))
5140 and then Entity
(Name
(Call
)) = Iter
5141 and then Present
(Parameter_Associations
(Call
))
5143 Param
:= First
(Parameter_Associations
(Call
));
5145 if Nkind
(Param
) = N_Explicit_Dereference
5146 and then Entity
(Prefix
(Param
)) = Trans_Id
5158 end Is_Iterated_Container
;
5162 Desig
: Entity_Id
:= Obj_Typ
;
5164 -- Start of processing for Is_Finalizable_Transient
5167 -- Handle access types
5169 if Is_Access_Type
(Desig
) then
5170 Desig
:= Available_View
(Designated_Type
(Desig
));
5174 Ekind_In
(Obj_Id
, E_Constant
, E_Variable
)
5175 and then Needs_Finalization
(Desig
)
5176 and then Requires_Transient_Scope
(Desig
)
5177 and then Nkind
(Rel_Node
) /= N_Simple_Return_Statement
5179 -- Do not consider renamed or 'reference-d transient objects because
5180 -- the act of renaming extends the object's lifetime.
5182 and then not Is_Aliased
(Obj_Id
, Decl
)
5184 -- Do not consider transient objects allocated on the heap since
5185 -- they are attached to a finalization master.
5187 and then not Is_Allocated
(Obj_Id
)
5189 -- If the transient object is a pointer, check that it is not
5190 -- initialized by a function that returns a pointer or acts as a
5191 -- renaming of another pointer.
5194 (not Is_Access_Type
(Obj_Typ
)
5195 or else not Initialized_By_Access
(Obj_Id
))
5197 -- Do not consider transient objects which act as indirect aliases
5198 -- of build-in-place function results.
5200 and then not Initialized_By_Aliased_BIP_Func_Call
(Obj_Id
)
5202 -- Do not consider conversions of tags to class-wide types
5204 and then not Is_Tag_To_Class_Wide_Conversion
(Obj_Id
)
5206 -- Do not consider iterators because those are treated as normal
5207 -- controlled objects and are processed by the usual finalization
5208 -- machinery. This avoids the double finalization of an iterator.
5210 and then not Is_Iterator
(Desig
)
5212 -- Do not consider containers in the context of iterator loops. Such
5213 -- transient objects must exist for as long as the loop is around,
5214 -- otherwise any operation carried out by the iterator will fail.
5216 and then not Is_Iterated_Container
(Obj_Id
, Decl
);
5217 end Is_Finalizable_Transient
;
5219 ---------------------------------
5220 -- Is_Fully_Repped_Tagged_Type --
5221 ---------------------------------
5223 function Is_Fully_Repped_Tagged_Type
(T
: Entity_Id
) return Boolean is
5224 U
: constant Entity_Id
:= Underlying_Type
(T
);
5228 if No
(U
) or else not Is_Tagged_Type
(U
) then
5230 elsif Has_Discriminants
(U
) then
5232 elsif not Has_Specified_Layout
(U
) then
5236 -- Here we have a tagged type, see if it has any unlayed out fields
5237 -- other than a possible tag and parent fields. If so, we return False.
5239 Comp
:= First_Component
(U
);
5240 while Present
(Comp
) loop
5241 if not Is_Tag
(Comp
)
5242 and then Chars
(Comp
) /= Name_uParent
5243 and then No
(Component_Clause
(Comp
))
5247 Next_Component
(Comp
);
5251 -- All components are layed out
5254 end Is_Fully_Repped_Tagged_Type
;
5256 ----------------------------------
5257 -- Is_Library_Level_Tagged_Type --
5258 ----------------------------------
5260 function Is_Library_Level_Tagged_Type
(Typ
: Entity_Id
) return Boolean is
5262 return Is_Tagged_Type
(Typ
) and then Is_Library_Level_Entity
(Typ
);
5263 end Is_Library_Level_Tagged_Type
;
5265 --------------------------
5266 -- Is_Non_BIP_Func_Call --
5267 --------------------------
5269 function Is_Non_BIP_Func_Call
(Expr
: Node_Id
) return Boolean is
5271 -- The expected call is of the format
5273 -- Func_Call'reference
5276 Nkind
(Expr
) = N_Reference
5277 and then Nkind
(Prefix
(Expr
)) = N_Function_Call
5278 and then not Is_Build_In_Place_Function_Call
(Prefix
(Expr
));
5279 end Is_Non_BIP_Func_Call
;
5281 ------------------------------------
5282 -- Is_Object_Access_BIP_Func_Call --
5283 ------------------------------------
5285 function Is_Object_Access_BIP_Func_Call
5287 Obj_Id
: Entity_Id
) return Boolean
5289 Access_Nam
: Name_Id
:= No_Name
;
5296 -- Build-in-place calls usually appear in 'reference format. Note that
5297 -- the accessibility check machinery may add an extra 'reference due to
5298 -- side effect removal.
5301 while Nkind
(Call
) = N_Reference
loop
5302 Call
:= Prefix
(Call
);
5305 if Nkind_In
(Call
, N_Qualified_Expression
,
5306 N_Unchecked_Type_Conversion
)
5308 Call
:= Expression
(Call
);
5311 if Is_Build_In_Place_Function_Call
(Call
) then
5313 -- Examine all parameter associations of the function call
5315 Param
:= First
(Parameter_Associations
(Call
));
5316 while Present
(Param
) loop
5317 if Nkind
(Param
) = N_Parameter_Association
5318 and then Nkind
(Selector_Name
(Param
)) = N_Identifier
5320 Formal
:= Selector_Name
(Param
);
5321 Actual
:= Explicit_Actual_Parameter
(Param
);
5323 -- Construct the name of formal BIPaccess. It is much easier to
5324 -- extract the name of the function using an arbitrary formal's
5325 -- scope rather than the Name field of Call.
5327 if Access_Nam
= No_Name
and then Present
(Entity
(Formal
)) then
5330 (Chars
(Scope
(Entity
(Formal
))),
5331 BIP_Formal_Suffix
(BIP_Object_Access
));
5334 -- A match for BIPaccess => Obj_Id'Unrestricted_Access has been
5337 if Chars
(Formal
) = Access_Nam
5338 and then Nkind
(Actual
) = N_Attribute_Reference
5339 and then Attribute_Name
(Actual
) = Name_Unrestricted_Access
5340 and then Nkind
(Prefix
(Actual
)) = N_Identifier
5341 and then Entity
(Prefix
(Actual
)) = Obj_Id
5352 end Is_Object_Access_BIP_Func_Call
;
5354 ----------------------------------
5355 -- Is_Possibly_Unaligned_Object --
5356 ----------------------------------
5358 function Is_Possibly_Unaligned_Object
(N
: Node_Id
) return Boolean is
5359 T
: constant Entity_Id
:= Etype
(N
);
5362 -- If renamed object, apply test to underlying object
5364 if Is_Entity_Name
(N
)
5365 and then Is_Object
(Entity
(N
))
5366 and then Present
(Renamed_Object
(Entity
(N
)))
5368 return Is_Possibly_Unaligned_Object
(Renamed_Object
(Entity
(N
)));
5371 -- Tagged and controlled types and aliased types are always aligned, as
5372 -- are concurrent types.
5375 or else Has_Controlled_Component
(T
)
5376 or else Is_Concurrent_Type
(T
)
5377 or else Is_Tagged_Type
(T
)
5378 or else Is_Controlled
(T
)
5383 -- If this is an element of a packed array, may be unaligned
5385 if Is_Ref_To_Bit_Packed_Array
(N
) then
5389 -- Case of indexed component reference: test whether prefix is unaligned
5391 if Nkind
(N
) = N_Indexed_Component
then
5392 return Is_Possibly_Unaligned_Object
(Prefix
(N
));
5394 -- Case of selected component reference
5396 elsif Nkind
(N
) = N_Selected_Component
then
5398 P
: constant Node_Id
:= Prefix
(N
);
5399 C
: constant Entity_Id
:= Entity
(Selector_Name
(N
));
5404 -- If component reference is for an array with non-static bounds,
5405 -- then it is always aligned: we can only process unaligned arrays
5406 -- with static bounds (more precisely compile time known bounds).
5408 if Is_Array_Type
(T
)
5409 and then not Compile_Time_Known_Bounds
(T
)
5414 -- If component is aliased, it is definitely properly aligned
5416 if Is_Aliased
(C
) then
5420 -- If component is for a type implemented as a scalar, and the
5421 -- record is packed, and the component is other than the first
5422 -- component of the record, then the component may be unaligned.
5424 if Is_Packed
(Etype
(P
))
5425 and then Represented_As_Scalar
(Etype
(C
))
5426 and then First_Entity
(Scope
(C
)) /= C
5431 -- Compute maximum possible alignment for T
5433 -- If alignment is known, then that settles things
5435 if Known_Alignment
(T
) then
5436 M
:= UI_To_Int
(Alignment
(T
));
5438 -- If alignment is not known, tentatively set max alignment
5441 M
:= Ttypes
.Maximum_Alignment
;
5443 -- We can reduce this if the Esize is known since the default
5444 -- alignment will never be more than the smallest power of 2
5445 -- that does not exceed this Esize value.
5447 if Known_Esize
(T
) then
5448 S
:= UI_To_Int
(Esize
(T
));
5450 while (M
/ 2) >= S
loop
5456 -- The following code is historical, it used to be present but it
5457 -- is too cautious, because the front-end does not know the proper
5458 -- default alignments for the target. Also, if the alignment is
5459 -- not known, the front end can't know in any case. If a copy is
5460 -- needed, the back-end will take care of it. This whole section
5461 -- including this comment can be removed later ???
5463 -- If the component reference is for a record that has a specified
5464 -- alignment, and we either know it is too small, or cannot tell,
5465 -- then the component may be unaligned.
5467 -- What is the following commented out code ???
5469 -- if Known_Alignment (Etype (P))
5470 -- and then Alignment (Etype (P)) < Ttypes.Maximum_Alignment
5471 -- and then M > Alignment (Etype (P))
5476 -- Case of component clause present which may specify an
5477 -- unaligned position.
5479 if Present
(Component_Clause
(C
)) then
5481 -- Otherwise we can do a test to make sure that the actual
5482 -- start position in the record, and the length, are both
5483 -- consistent with the required alignment. If not, we know
5484 -- that we are unaligned.
5487 Align_In_Bits
: constant Nat
:= M
* System_Storage_Unit
;
5489 if Component_Bit_Offset
(C
) mod Align_In_Bits
/= 0
5490 or else Esize
(C
) mod Align_In_Bits
/= 0
5497 -- Otherwise, for a component reference, test prefix
5499 return Is_Possibly_Unaligned_Object
(P
);
5502 -- If not a component reference, must be aligned
5507 end Is_Possibly_Unaligned_Object
;
5509 ---------------------------------
5510 -- Is_Possibly_Unaligned_Slice --
5511 ---------------------------------
5513 function Is_Possibly_Unaligned_Slice
(N
: Node_Id
) return Boolean is
5515 -- Go to renamed object
5517 if Is_Entity_Name
(N
)
5518 and then Is_Object
(Entity
(N
))
5519 and then Present
(Renamed_Object
(Entity
(N
)))
5521 return Is_Possibly_Unaligned_Slice
(Renamed_Object
(Entity
(N
)));
5524 -- The reference must be a slice
5526 if Nkind
(N
) /= N_Slice
then
5530 -- We only need to worry if the target has strict alignment
5532 if not Target_Strict_Alignment
then
5536 -- If it is a slice, then look at the array type being sliced
5539 Sarr
: constant Node_Id
:= Prefix
(N
);
5540 -- Prefix of the slice, i.e. the array being sliced
5542 Styp
: constant Entity_Id
:= Etype
(Prefix
(N
));
5543 -- Type of the array being sliced
5549 -- The problems arise if the array object that is being sliced
5550 -- is a component of a record or array, and we cannot guarantee
5551 -- the alignment of the array within its containing object.
5553 -- To investigate this, we look at successive prefixes to see
5554 -- if we have a worrisome indexed or selected component.
5558 -- Case of array is part of an indexed component reference
5560 if Nkind
(Pref
) = N_Indexed_Component
then
5561 Ptyp
:= Etype
(Prefix
(Pref
));
5563 -- The only problematic case is when the array is packed, in
5564 -- which case we really know nothing about the alignment of
5565 -- individual components.
5567 if Is_Bit_Packed_Array
(Ptyp
) then
5571 -- Case of array is part of a selected component reference
5573 elsif Nkind
(Pref
) = N_Selected_Component
then
5574 Ptyp
:= Etype
(Prefix
(Pref
));
5576 -- We are definitely in trouble if the record in question
5577 -- has an alignment, and either we know this alignment is
5578 -- inconsistent with the alignment of the slice, or we don't
5579 -- know what the alignment of the slice should be.
5581 if Known_Alignment
(Ptyp
)
5582 and then (Unknown_Alignment
(Styp
)
5583 or else Alignment
(Styp
) > Alignment
(Ptyp
))
5588 -- We are in potential trouble if the record type is packed.
5589 -- We could special case when we know that the array is the
5590 -- first component, but that's not such a simple case ???
5592 if Is_Packed
(Ptyp
) then
5596 -- We are in trouble if there is a component clause, and
5597 -- either we do not know the alignment of the slice, or
5598 -- the alignment of the slice is inconsistent with the
5599 -- bit position specified by the component clause.
5602 Field
: constant Entity_Id
:= Entity
(Selector_Name
(Pref
));
5604 if Present
(Component_Clause
(Field
))
5606 (Unknown_Alignment
(Styp
)
5608 (Component_Bit_Offset
(Field
) mod
5609 (System_Storage_Unit
* Alignment
(Styp
))) /= 0)
5615 -- For cases other than selected or indexed components we know we
5616 -- are OK, since no issues arise over alignment.
5622 -- We processed an indexed component or selected component
5623 -- reference that looked safe, so keep checking prefixes.
5625 Pref
:= Prefix
(Pref
);
5628 end Is_Possibly_Unaligned_Slice
;
5630 -------------------------------
5631 -- Is_Related_To_Func_Return --
5632 -------------------------------
5634 function Is_Related_To_Func_Return
(Id
: Entity_Id
) return Boolean is
5635 Expr
: constant Node_Id
:= Related_Expression
(Id
);
5639 and then Nkind
(Expr
) = N_Explicit_Dereference
5640 and then Nkind
(Parent
(Expr
)) = N_Simple_Return_Statement
;
5641 end Is_Related_To_Func_Return
;
5643 --------------------------------
5644 -- Is_Ref_To_Bit_Packed_Array --
5645 --------------------------------
5647 function Is_Ref_To_Bit_Packed_Array
(N
: Node_Id
) return Boolean is
5652 if Is_Entity_Name
(N
)
5653 and then Is_Object
(Entity
(N
))
5654 and then Present
(Renamed_Object
(Entity
(N
)))
5656 return Is_Ref_To_Bit_Packed_Array
(Renamed_Object
(Entity
(N
)));
5659 if Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
5660 if Is_Bit_Packed_Array
(Etype
(Prefix
(N
))) then
5663 Result
:= Is_Ref_To_Bit_Packed_Array
(Prefix
(N
));
5666 if Result
and then Nkind
(N
) = N_Indexed_Component
then
5667 Expr
:= First
(Expressions
(N
));
5668 while Present
(Expr
) loop
5669 Force_Evaluation
(Expr
);
5679 end Is_Ref_To_Bit_Packed_Array
;
5681 --------------------------------
5682 -- Is_Ref_To_Bit_Packed_Slice --
5683 --------------------------------
5685 function Is_Ref_To_Bit_Packed_Slice
(N
: Node_Id
) return Boolean is
5687 if Nkind
(N
) = N_Type_Conversion
then
5688 return Is_Ref_To_Bit_Packed_Slice
(Expression
(N
));
5690 elsif Is_Entity_Name
(N
)
5691 and then Is_Object
(Entity
(N
))
5692 and then Present
(Renamed_Object
(Entity
(N
)))
5694 return Is_Ref_To_Bit_Packed_Slice
(Renamed_Object
(Entity
(N
)));
5696 elsif Nkind
(N
) = N_Slice
5697 and then Is_Bit_Packed_Array
(Etype
(Prefix
(N
)))
5701 elsif Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
5702 return Is_Ref_To_Bit_Packed_Slice
(Prefix
(N
));
5707 end Is_Ref_To_Bit_Packed_Slice
;
5709 -----------------------
5710 -- Is_Renamed_Object --
5711 -----------------------
5713 function Is_Renamed_Object
(N
: Node_Id
) return Boolean is
5714 Pnod
: constant Node_Id
:= Parent
(N
);
5715 Kind
: constant Node_Kind
:= Nkind
(Pnod
);
5717 if Kind
= N_Object_Renaming_Declaration
then
5719 elsif Nkind_In
(Kind
, N_Indexed_Component
, N_Selected_Component
) then
5720 return Is_Renamed_Object
(Pnod
);
5724 end Is_Renamed_Object
;
5726 --------------------------------------
5727 -- Is_Secondary_Stack_BIP_Func_Call --
5728 --------------------------------------
5730 function Is_Secondary_Stack_BIP_Func_Call
(Expr
: Node_Id
) return Boolean is
5731 Alloc_Nam
: Name_Id
:= No_Name
;
5733 Call
: Node_Id
:= Expr
;
5738 -- Build-in-place calls usually appear in 'reference format. Note that
5739 -- the accessibility check machinery may add an extra 'reference due to
5740 -- side effect removal.
5742 while Nkind
(Call
) = N_Reference
loop
5743 Call
:= Prefix
(Call
);
5746 if Nkind_In
(Call
, N_Qualified_Expression
,
5747 N_Unchecked_Type_Conversion
)
5749 Call
:= Expression
(Call
);
5752 if Is_Build_In_Place_Function_Call
(Call
) then
5754 -- Examine all parameter associations of the function call
5756 Param
:= First
(Parameter_Associations
(Call
));
5757 while Present
(Param
) loop
5758 if Nkind
(Param
) = N_Parameter_Association
5759 and then Nkind
(Selector_Name
(Param
)) = N_Identifier
5761 Formal
:= Selector_Name
(Param
);
5762 Actual
:= Explicit_Actual_Parameter
(Param
);
5764 -- Construct the name of formal BIPalloc. It is much easier to
5765 -- extract the name of the function using an arbitrary formal's
5766 -- scope rather than the Name field of Call.
5768 if Alloc_Nam
= No_Name
and then Present
(Entity
(Formal
)) then
5771 (Chars
(Scope
(Entity
(Formal
))),
5772 BIP_Formal_Suffix
(BIP_Alloc_Form
));
5775 -- A match for BIPalloc => 2 has been found
5777 if Chars
(Formal
) = Alloc_Nam
5778 and then Nkind
(Actual
) = N_Integer_Literal
5779 and then Intval
(Actual
) = Uint_2
5790 end Is_Secondary_Stack_BIP_Func_Call
;
5792 -------------------------------------
5793 -- Is_Tag_To_Class_Wide_Conversion --
5794 -------------------------------------
5796 function Is_Tag_To_Class_Wide_Conversion
5797 (Obj_Id
: Entity_Id
) return Boolean
5799 Expr
: constant Node_Id
:= Expression
(Parent
(Obj_Id
));
5803 Is_Class_Wide_Type
(Etype
(Obj_Id
))
5804 and then Present
(Expr
)
5805 and then Nkind
(Expr
) = N_Unchecked_Type_Conversion
5806 and then Etype
(Expression
(Expr
)) = RTE
(RE_Tag
);
5807 end Is_Tag_To_Class_Wide_Conversion
;
5809 ----------------------------
5810 -- Is_Untagged_Derivation --
5811 ----------------------------
5813 function Is_Untagged_Derivation
(T
: Entity_Id
) return Boolean is
5815 return (not Is_Tagged_Type
(T
) and then Is_Derived_Type
(T
))
5817 (Is_Private_Type
(T
) and then Present
(Full_View
(T
))
5818 and then not Is_Tagged_Type
(Full_View
(T
))
5819 and then Is_Derived_Type
(Full_View
(T
))
5820 and then Etype
(Full_View
(T
)) /= T
);
5821 end Is_Untagged_Derivation
;
5823 ---------------------------
5824 -- Is_Volatile_Reference --
5825 ---------------------------
5827 function Is_Volatile_Reference
(N
: Node_Id
) return Boolean is
5829 -- Only source references are to be treated as volatile, internally
5830 -- generated stuff cannot have volatile external effects.
5832 if not Comes_From_Source
(N
) then
5835 -- Never true for reference to a type
5837 elsif Is_Entity_Name
(N
) and then Is_Type
(Entity
(N
)) then
5840 -- Never true for a compile time known constant
5842 elsif Compile_Time_Known_Value
(N
) then
5845 -- True if object reference with volatile type
5847 elsif Is_Volatile_Object
(N
) then
5850 -- True if reference to volatile entity
5852 elsif Is_Entity_Name
(N
) then
5853 return Treat_As_Volatile
(Entity
(N
));
5855 -- True for slice of volatile array
5857 elsif Nkind
(N
) = N_Slice
then
5858 return Is_Volatile_Reference
(Prefix
(N
));
5860 -- True if volatile component
5862 elsif Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
5863 if (Is_Entity_Name
(Prefix
(N
))
5864 and then Has_Volatile_Components
(Entity
(Prefix
(N
))))
5865 or else (Present
(Etype
(Prefix
(N
)))
5866 and then Has_Volatile_Components
(Etype
(Prefix
(N
))))
5870 return Is_Volatile_Reference
(Prefix
(N
));
5878 end Is_Volatile_Reference
;
5880 --------------------
5881 -- Kill_Dead_Code --
5882 --------------------
5884 procedure Kill_Dead_Code
(N
: Node_Id
; Warn
: Boolean := False) is
5885 W
: Boolean := Warn
;
5886 -- Set False if warnings suppressed
5890 Remove_Warning_Messages
(N
);
5892 -- Generate warning if appropriate
5896 -- We suppress the warning if this code is under control of an
5897 -- if statement, whose condition is a simple identifier, and
5898 -- either we are in an instance, or warnings off is set for this
5899 -- identifier. The reason for killing it in the instance case is
5900 -- that it is common and reasonable for code to be deleted in
5901 -- instances for various reasons.
5903 -- Could we use Is_Statically_Unevaluated here???
5905 if Nkind
(Parent
(N
)) = N_If_Statement
then
5907 C
: constant Node_Id
:= Condition
(Parent
(N
));
5909 if Nkind
(C
) = N_Identifier
5912 or else (Present
(Entity
(C
))
5913 and then Has_Warnings_Off
(Entity
(C
))))
5920 -- Generate warning if not suppressed
5924 ("?t?this code can never be executed and has been deleted!",
5929 -- Recurse into block statements and bodies to process declarations
5932 if Nkind
(N
) = N_Block_Statement
5933 or else Nkind
(N
) = N_Subprogram_Body
5934 or else Nkind
(N
) = N_Package_Body
5936 Kill_Dead_Code
(Declarations
(N
), False);
5937 Kill_Dead_Code
(Statements
(Handled_Statement_Sequence
(N
)));
5939 if Nkind
(N
) = N_Subprogram_Body
then
5940 Set_Is_Eliminated
(Defining_Entity
(N
));
5943 elsif Nkind
(N
) = N_Package_Declaration
then
5944 Kill_Dead_Code
(Visible_Declarations
(Specification
(N
)));
5945 Kill_Dead_Code
(Private_Declarations
(Specification
(N
)));
5947 -- ??? After this point, Delete_Tree has been called on all
5948 -- declarations in Specification (N), so references to entities
5949 -- therein look suspicious.
5952 E
: Entity_Id
:= First_Entity
(Defining_Entity
(N
));
5955 while Present
(E
) loop
5956 if Ekind
(E
) = E_Operator
then
5957 Set_Is_Eliminated
(E
);
5964 -- Recurse into composite statement to kill individual statements in
5965 -- particular instantiations.
5967 elsif Nkind
(N
) = N_If_Statement
then
5968 Kill_Dead_Code
(Then_Statements
(N
));
5969 Kill_Dead_Code
(Elsif_Parts
(N
));
5970 Kill_Dead_Code
(Else_Statements
(N
));
5972 elsif Nkind
(N
) = N_Loop_Statement
then
5973 Kill_Dead_Code
(Statements
(N
));
5975 elsif Nkind
(N
) = N_Case_Statement
then
5979 Alt
:= First
(Alternatives
(N
));
5980 while Present
(Alt
) loop
5981 Kill_Dead_Code
(Statements
(Alt
));
5986 elsif Nkind
(N
) = N_Case_Statement_Alternative
then
5987 Kill_Dead_Code
(Statements
(N
));
5989 -- Deal with dead instances caused by deleting instantiations
5991 elsif Nkind
(N
) in N_Generic_Instantiation
then
5992 Remove_Dead_Instance
(N
);
5997 -- Case where argument is a list of nodes to be killed
5999 procedure Kill_Dead_Code
(L
: List_Id
; Warn
: Boolean := False) is
6006 if Is_Non_Empty_List
(L
) then
6008 while Present
(N
) loop
6009 Kill_Dead_Code
(N
, W
);
6016 ------------------------
6017 -- Known_Non_Negative --
6018 ------------------------
6020 function Known_Non_Negative
(Opnd
: Node_Id
) return Boolean is
6022 if Is_OK_Static_Expression
(Opnd
) and then Expr_Value
(Opnd
) >= 0 then
6027 Lo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Opnd
));
6030 Is_OK_Static_Expression
(Lo
) and then Expr_Value
(Lo
) >= 0;
6033 end Known_Non_Negative
;
6035 --------------------
6036 -- Known_Non_Null --
6037 --------------------
6039 function Known_Non_Null
(N
: Node_Id
) return Boolean is
6041 -- Checks for case where N is an entity reference
6043 if Is_Entity_Name
(N
) and then Present
(Entity
(N
)) then
6045 E
: constant Entity_Id
:= Entity
(N
);
6050 -- First check if we are in decisive conditional
6052 Get_Current_Value_Condition
(N
, Op
, Val
);
6054 if Known_Null
(Val
) then
6055 if Op
= N_Op_Eq
then
6057 elsif Op
= N_Op_Ne
then
6062 -- If OK to do replacement, test Is_Known_Non_Null flag
6064 if OK_To_Do_Constant_Replacement
(E
) then
6065 return Is_Known_Non_Null
(E
);
6067 -- Otherwise if not safe to do replacement, then say so
6074 -- True if access attribute
6076 elsif Nkind
(N
) = N_Attribute_Reference
6077 and then Nam_In
(Attribute_Name
(N
), Name_Access
,
6078 Name_Unchecked_Access
,
6079 Name_Unrestricted_Access
)
6083 -- True if allocator
6085 elsif Nkind
(N
) = N_Allocator
then
6088 -- For a conversion, true if expression is known non-null
6090 elsif Nkind
(N
) = N_Type_Conversion
then
6091 return Known_Non_Null
(Expression
(N
));
6093 -- Above are all cases where the value could be determined to be
6094 -- non-null. In all other cases, we don't know, so return False.
6105 function Known_Null
(N
: Node_Id
) return Boolean is
6107 -- Checks for case where N is an entity reference
6109 if Is_Entity_Name
(N
) and then Present
(Entity
(N
)) then
6111 E
: constant Entity_Id
:= Entity
(N
);
6116 -- Constant null value is for sure null
6118 if Ekind
(E
) = E_Constant
6119 and then Known_Null
(Constant_Value
(E
))
6124 -- First check if we are in decisive conditional
6126 Get_Current_Value_Condition
(N
, Op
, Val
);
6128 if Known_Null
(Val
) then
6129 if Op
= N_Op_Eq
then
6131 elsif Op
= N_Op_Ne
then
6136 -- If OK to do replacement, test Is_Known_Null flag
6138 if OK_To_Do_Constant_Replacement
(E
) then
6139 return Is_Known_Null
(E
);
6141 -- Otherwise if not safe to do replacement, then say so
6148 -- True if explicit reference to null
6150 elsif Nkind
(N
) = N_Null
then
6153 -- For a conversion, true if expression is known null
6155 elsif Nkind
(N
) = N_Type_Conversion
then
6156 return Known_Null
(Expression
(N
));
6158 -- Above are all cases where the value could be determined to be null.
6159 -- In all other cases, we don't know, so return False.
6166 -----------------------------
6167 -- Make_CW_Equivalent_Type --
6168 -----------------------------
6170 -- Create a record type used as an equivalent of any member of the class
6171 -- which takes its size from exp.
6173 -- Generate the following code:
6175 -- type Equiv_T is record
6176 -- _parent : T (List of discriminant constraints taken from Exp);
6177 -- Ext__50 : Storage_Array (1 .. (Exp'size - Typ'object_size)/8);
6180 -- ??? Note that this type does not guarantee same alignment as all
6183 function Make_CW_Equivalent_Type
6185 E
: Node_Id
) return Entity_Id
6187 Loc
: constant Source_Ptr
:= Sloc
(E
);
6188 Root_Typ
: constant Entity_Id
:= Root_Type
(T
);
6189 List_Def
: constant List_Id
:= Empty_List
;
6190 Comp_List
: constant List_Id
:= New_List
;
6191 Equiv_Type
: Entity_Id
;
6192 Range_Type
: Entity_Id
;
6193 Str_Type
: Entity_Id
;
6194 Constr_Root
: Entity_Id
;
6198 -- If the root type is already constrained, there are no discriminants
6199 -- in the expression.
6201 if not Has_Discriminants
(Root_Typ
)
6202 or else Is_Constrained
(Root_Typ
)
6204 Constr_Root
:= Root_Typ
;
6206 -- At this point in the expansion, non-limited view of the type
6207 -- must be available, otherwise the error will be reported later.
6209 if From_Limited_With
(Constr_Root
)
6210 and then Present
(Non_Limited_View
(Constr_Root
))
6212 Constr_Root
:= Non_Limited_View
(Constr_Root
);
6216 Constr_Root
:= Make_Temporary
(Loc
, 'R');
6218 -- subtype cstr__n is T (List of discr constraints taken from Exp)
6220 Append_To
(List_Def
,
6221 Make_Subtype_Declaration
(Loc
,
6222 Defining_Identifier
=> Constr_Root
,
6223 Subtype_Indication
=> Make_Subtype_From_Expr
(E
, Root_Typ
)));
6226 -- Generate the range subtype declaration
6228 Range_Type
:= Make_Temporary
(Loc
, 'G');
6230 if not Is_Interface
(Root_Typ
) then
6232 -- subtype rg__xx is
6233 -- Storage_Offset range 1 .. (Expr'size - typ'size) / Storage_Unit
6236 Make_Op_Subtract
(Loc
,
6238 Make_Attribute_Reference
(Loc
,
6240 OK_Convert_To
(T
, Duplicate_Subexpr_No_Checks
(E
)),
6241 Attribute_Name
=> Name_Size
),
6243 Make_Attribute_Reference
(Loc
,
6244 Prefix
=> New_Occurrence_Of
(Constr_Root
, Loc
),
6245 Attribute_Name
=> Name_Object_Size
));
6247 -- subtype rg__xx is
6248 -- Storage_Offset range 1 .. Expr'size / Storage_Unit
6251 Make_Attribute_Reference
(Loc
,
6253 OK_Convert_To
(T
, Duplicate_Subexpr_No_Checks
(E
)),
6254 Attribute_Name
=> Name_Size
);
6257 Set_Paren_Count
(Sizexpr
, 1);
6259 Append_To
(List_Def
,
6260 Make_Subtype_Declaration
(Loc
,
6261 Defining_Identifier
=> Range_Type
,
6262 Subtype_Indication
=>
6263 Make_Subtype_Indication
(Loc
,
6264 Subtype_Mark
=> New_Occurrence_Of
(RTE
(RE_Storage_Offset
), Loc
),
6265 Constraint
=> Make_Range_Constraint
(Loc
,
6268 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
6270 Make_Op_Divide
(Loc
,
6271 Left_Opnd
=> Sizexpr
,
6272 Right_Opnd
=> Make_Integer_Literal
(Loc
,
6273 Intval
=> System_Storage_Unit
)))))));
6275 -- subtype str__nn is Storage_Array (rg__x);
6277 Str_Type
:= Make_Temporary
(Loc
, 'S');
6278 Append_To
(List_Def
,
6279 Make_Subtype_Declaration
(Loc
,
6280 Defining_Identifier
=> Str_Type
,
6281 Subtype_Indication
=>
6282 Make_Subtype_Indication
(Loc
,
6283 Subtype_Mark
=> New_Occurrence_Of
(RTE
(RE_Storage_Array
), Loc
),
6285 Make_Index_Or_Discriminant_Constraint
(Loc
,
6287 New_List
(New_Occurrence_Of
(Range_Type
, Loc
))))));
6289 -- type Equiv_T is record
6290 -- [ _parent : Tnn; ]
6294 Equiv_Type
:= Make_Temporary
(Loc
, 'T');
6295 Set_Ekind
(Equiv_Type
, E_Record_Type
);
6296 Set_Parent_Subtype
(Equiv_Type
, Constr_Root
);
6298 -- Set Is_Class_Wide_Equivalent_Type very early to trigger the special
6299 -- treatment for this type. In particular, even though _parent's type
6300 -- is a controlled type or contains controlled components, we do not
6301 -- want to set Has_Controlled_Component on it to avoid making it gain
6302 -- an unwanted _controller component.
6304 Set_Is_Class_Wide_Equivalent_Type
(Equiv_Type
);
6306 -- A class-wide equivalent type does not require initialization
6308 Set_Suppress_Initialization
(Equiv_Type
);
6310 if not Is_Interface
(Root_Typ
) then
6311 Append_To
(Comp_List
,
6312 Make_Component_Declaration
(Loc
,
6313 Defining_Identifier
=>
6314 Make_Defining_Identifier
(Loc
, Name_uParent
),
6315 Component_Definition
=>
6316 Make_Component_Definition
(Loc
,
6317 Aliased_Present
=> False,
6318 Subtype_Indication
=> New_Occurrence_Of
(Constr_Root
, Loc
))));
6321 Append_To
(Comp_List
,
6322 Make_Component_Declaration
(Loc
,
6323 Defining_Identifier
=> Make_Temporary
(Loc
, 'C'),
6324 Component_Definition
=>
6325 Make_Component_Definition
(Loc
,
6326 Aliased_Present
=> False,
6327 Subtype_Indication
=> New_Occurrence_Of
(Str_Type
, Loc
))));
6329 Append_To
(List_Def
,
6330 Make_Full_Type_Declaration
(Loc
,
6331 Defining_Identifier
=> Equiv_Type
,
6333 Make_Record_Definition
(Loc
,
6335 Make_Component_List
(Loc
,
6336 Component_Items
=> Comp_List
,
6337 Variant_Part
=> Empty
))));
6339 -- Suppress all checks during the analysis of the expanded code to avoid
6340 -- the generation of spurious warnings under ZFP run-time.
6342 Insert_Actions
(E
, List_Def
, Suppress
=> All_Checks
);
6344 end Make_CW_Equivalent_Type
;
6346 -------------------------
6347 -- Make_Invariant_Call --
6348 -------------------------
6350 function Make_Invariant_Call
(Expr
: Node_Id
) return Node_Id
is
6351 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
6355 Typ
:= Etype
(Expr
);
6357 -- Subtypes may be subject to invariants coming from their respective
6358 -- base types. The subtype may be fully or partially private.
6360 if Ekind_In
(Typ
, E_Array_Subtype
,
6363 E_Record_Subtype_With_Private
)
6365 Typ
:= Base_Type
(Typ
);
6369 (Has_Invariants
(Typ
) and then Present
(Invariant_Procedure
(Typ
)));
6372 Make_Procedure_Call_Statement
(Loc
,
6374 New_Occurrence_Of
(Invariant_Procedure
(Typ
), Loc
),
6375 Parameter_Associations
=> New_List
(Relocate_Node
(Expr
)));
6376 end Make_Invariant_Call
;
6378 ------------------------
6379 -- Make_Literal_Range --
6380 ------------------------
6382 function Make_Literal_Range
6384 Literal_Typ
: Entity_Id
) return Node_Id
6386 Lo
: constant Node_Id
:=
6387 New_Copy_Tree
(String_Literal_Low_Bound
(Literal_Typ
));
6388 Index
: constant Entity_Id
:= Etype
(Lo
);
6391 Length_Expr
: constant Node_Id
:=
6392 Make_Op_Subtract
(Loc
,
6394 Make_Integer_Literal
(Loc
,
6395 Intval
=> String_Literal_Length
(Literal_Typ
)),
6397 Make_Integer_Literal
(Loc
, 1));
6400 Set_Analyzed
(Lo
, False);
6402 if Is_Integer_Type
(Index
) then
6405 Left_Opnd
=> New_Copy_Tree
(Lo
),
6406 Right_Opnd
=> Length_Expr
);
6409 Make_Attribute_Reference
(Loc
,
6410 Attribute_Name
=> Name_Val
,
6411 Prefix
=> New_Occurrence_Of
(Index
, Loc
),
6412 Expressions
=> New_List
(
6415 Make_Attribute_Reference
(Loc
,
6416 Attribute_Name
=> Name_Pos
,
6417 Prefix
=> New_Occurrence_Of
(Index
, Loc
),
6418 Expressions
=> New_List
(New_Copy_Tree
(Lo
))),
6419 Right_Opnd
=> Length_Expr
)));
6426 end Make_Literal_Range
;
6428 --------------------------
6429 -- Make_Non_Empty_Check --
6430 --------------------------
6432 function Make_Non_Empty_Check
6434 N
: Node_Id
) return Node_Id
6440 Make_Attribute_Reference
(Loc
,
6441 Attribute_Name
=> Name_Length
,
6442 Prefix
=> Duplicate_Subexpr_No_Checks
(N
, Name_Req
=> True)),
6444 Make_Integer_Literal
(Loc
, 0));
6445 end Make_Non_Empty_Check
;
6447 -------------------------
6448 -- Make_Predicate_Call --
6449 -------------------------
6451 function Make_Predicate_Call
6454 Mem
: Boolean := False) return Node_Id
6456 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
6460 Save_Ghost_Mode
: constant Ghost_Mode_Type
:= Ghost_Mode
;
6463 pragma Assert
(Present
(Predicate_Function
(Typ
)));
6465 -- The related type may be subject to pragma Ghost. Set the mode now to
6466 -- ensure that the call is properly marked as Ghost.
6468 Set_Ghost_Mode_From_Entity
(Typ
);
6470 -- Call special membership version if requested and available
6473 PFM
:= Predicate_Function_M
(Typ
);
6475 if Present
(PFM
) then
6477 Make_Function_Call
(Loc
,
6478 Name
=> New_Occurrence_Of
(PFM
, Loc
),
6479 Parameter_Associations
=> New_List
(Relocate_Node
(Expr
)));
6481 Ghost_Mode
:= Save_Ghost_Mode
;
6486 -- Case of calling normal predicate function
6489 Make_Function_Call
(Loc
,
6491 New_Occurrence_Of
(Predicate_Function
(Typ
), Loc
),
6492 Parameter_Associations
=> New_List
(Relocate_Node
(Expr
)));
6494 Ghost_Mode
:= Save_Ghost_Mode
;
6496 end Make_Predicate_Call
;
6498 --------------------------
6499 -- Make_Predicate_Check --
6500 --------------------------
6502 function Make_Predicate_Check
6504 Expr
: Node_Id
) return Node_Id
6506 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
6511 -- If predicate checks are suppressed, then return a null statement. For
6512 -- this call, we check only the scope setting. If the caller wants to
6513 -- check a specific entity's setting, they must do it manually.
6515 if Predicate_Checks_Suppressed
(Empty
) then
6516 return Make_Null_Statement
(Loc
);
6519 -- Do not generate a check within an internal subprogram (stream
6520 -- functions and the like, including including predicate functions).
6522 if Within_Internal_Subprogram
then
6523 return Make_Null_Statement
(Loc
);
6526 -- Compute proper name to use, we need to get this right so that the
6527 -- right set of check policies apply to the Check pragma we are making.
6529 if Has_Dynamic_Predicate_Aspect
(Typ
) then
6530 Nam
:= Name_Dynamic_Predicate
;
6531 elsif Has_Static_Predicate_Aspect
(Typ
) then
6532 Nam
:= Name_Static_Predicate
;
6534 Nam
:= Name_Predicate
;
6537 Arg_List
:= New_List
(
6538 Make_Pragma_Argument_Association
(Loc
,
6539 Expression
=> Make_Identifier
(Loc
, Nam
)),
6540 Make_Pragma_Argument_Association
(Loc
,
6541 Expression
=> Make_Predicate_Call
(Typ
, Expr
)));
6543 if Has_Aspect
(Typ
, Aspect_Predicate_Failure
) then
6544 Append_To
(Arg_List
,
6545 Make_Pragma_Argument_Association
(Loc
,
6548 (Expression
(Find_Aspect
(Typ
, Aspect_Predicate_Failure
)))));
6553 Pragma_Identifier
=> Make_Identifier
(Loc
, Name_Check
),
6554 Pragma_Argument_Associations
=> Arg_List
);
6555 end Make_Predicate_Check
;
6557 ----------------------------
6558 -- Make_Subtype_From_Expr --
6559 ----------------------------
6561 -- 1. If Expr is an unconstrained array expression, creates
6562 -- Unc_Type(Expr'first(1)..Expr'last(1),..., Expr'first(n)..Expr'last(n))
6564 -- 2. If Expr is a unconstrained discriminated type expression, creates
6565 -- Unc_Type(Expr.Discr1, ... , Expr.Discr_n)
6567 -- 3. If Expr is class-wide, creates an implicit class-wide subtype
6569 function Make_Subtype_From_Expr
6571 Unc_Typ
: Entity_Id
;
6572 Related_Id
: Entity_Id
:= Empty
) return Node_Id
6574 List_Constr
: constant List_Id
:= New_List
;
6575 Loc
: constant Source_Ptr
:= Sloc
(E
);
6578 Full_Subtyp
: Entity_Id
;
6579 High_Bound
: Entity_Id
;
6580 Index_Typ
: Entity_Id
;
6581 Low_Bound
: Entity_Id
;
6582 Priv_Subtyp
: Entity_Id
;
6586 if Is_Private_Type
(Unc_Typ
)
6587 and then Has_Unknown_Discriminants
(Unc_Typ
)
6589 -- The caller requests a unique external name for both the private
6590 -- and the full subtype.
6592 if Present
(Related_Id
) then
6594 Make_Defining_Identifier
(Loc
,
6595 Chars
=> New_External_Name
(Chars
(Related_Id
), 'C'));
6597 Make_Defining_Identifier
(Loc
,
6598 Chars
=> New_External_Name
(Chars
(Related_Id
), 'P'));
6601 Full_Subtyp
:= Make_Temporary
(Loc
, 'C');
6602 Priv_Subtyp
:= Make_Temporary
(Loc
, 'P');
6605 -- Prepare the subtype completion. Use the base type to find the
6606 -- underlying type because the type may be a generic actual or an
6607 -- explicit subtype.
6609 Utyp
:= Underlying_Type
(Base_Type
(Unc_Typ
));
6612 Unchecked_Convert_To
(Utyp
, Duplicate_Subexpr_No_Checks
(E
));
6613 Set_Parent
(Full_Exp
, Parent
(E
));
6616 Make_Subtype_Declaration
(Loc
,
6617 Defining_Identifier
=> Full_Subtyp
,
6618 Subtype_Indication
=> Make_Subtype_From_Expr
(Full_Exp
, Utyp
)));
6620 -- Define the dummy private subtype
6622 Set_Ekind
(Priv_Subtyp
, Subtype_Kind
(Ekind
(Unc_Typ
)));
6623 Set_Etype
(Priv_Subtyp
, Base_Type
(Unc_Typ
));
6624 Set_Scope
(Priv_Subtyp
, Full_Subtyp
);
6625 Set_Is_Constrained
(Priv_Subtyp
);
6626 Set_Is_Tagged_Type
(Priv_Subtyp
, Is_Tagged_Type
(Unc_Typ
));
6627 Set_Is_Itype
(Priv_Subtyp
);
6628 Set_Associated_Node_For_Itype
(Priv_Subtyp
, E
);
6630 if Is_Tagged_Type
(Priv_Subtyp
) then
6632 (Base_Type
(Priv_Subtyp
), Class_Wide_Type
(Unc_Typ
));
6633 Set_Direct_Primitive_Operations
(Priv_Subtyp
,
6634 Direct_Primitive_Operations
(Unc_Typ
));
6637 Set_Full_View
(Priv_Subtyp
, Full_Subtyp
);
6639 return New_Occurrence_Of
(Priv_Subtyp
, Loc
);
6641 elsif Is_Array_Type
(Unc_Typ
) then
6642 Index_Typ
:= First_Index
(Unc_Typ
);
6643 for J
in 1 .. Number_Dimensions
(Unc_Typ
) loop
6645 -- Capture the bounds of each index constraint in case the context
6646 -- is an object declaration of an unconstrained type initialized
6647 -- by a function call:
6649 -- Obj : Unconstr_Typ := Func_Call;
6651 -- This scenario requires secondary scope management and the index
6652 -- constraint cannot depend on the temporary used to capture the
6653 -- result of the function call.
6656 -- Temp : Unconstr_Typ_Ptr := Func_Call'reference;
6657 -- subtype S is Unconstr_Typ (Temp.all'First .. Temp.all'Last);
6658 -- Obj : S := Temp.all;
6659 -- SS_Release; -- Temp is gone at this point, bounds of S are
6663 -- Low_Bound : constant Base_Type (Index_Typ) := E'First (J);
6665 Low_Bound
:= Make_Temporary
(Loc
, 'B');
6667 Make_Object_Declaration
(Loc
,
6668 Defining_Identifier
=> Low_Bound
,
6669 Object_Definition
=>
6670 New_Occurrence_Of
(Base_Type
(Etype
(Index_Typ
)), Loc
),
6671 Constant_Present
=> True,
6673 Make_Attribute_Reference
(Loc
,
6674 Prefix
=> Duplicate_Subexpr_No_Checks
(E
),
6675 Attribute_Name
=> Name_First
,
6676 Expressions
=> New_List
(
6677 Make_Integer_Literal
(Loc
, J
)))));
6680 -- High_Bound : constant Base_Type (Index_Typ) := E'Last (J);
6682 High_Bound
:= Make_Temporary
(Loc
, 'B');
6684 Make_Object_Declaration
(Loc
,
6685 Defining_Identifier
=> High_Bound
,
6686 Object_Definition
=>
6687 New_Occurrence_Of
(Base_Type
(Etype
(Index_Typ
)), Loc
),
6688 Constant_Present
=> True,
6690 Make_Attribute_Reference
(Loc
,
6691 Prefix
=> Duplicate_Subexpr_No_Checks
(E
),
6692 Attribute_Name
=> Name_Last
,
6693 Expressions
=> New_List
(
6694 Make_Integer_Literal
(Loc
, J
)))));
6696 Append_To
(List_Constr
,
6698 Low_Bound
=> New_Occurrence_Of
(Low_Bound
, Loc
),
6699 High_Bound
=> New_Occurrence_Of
(High_Bound
, Loc
)));
6701 Index_Typ
:= Next_Index
(Index_Typ
);
6704 elsif Is_Class_Wide_Type
(Unc_Typ
) then
6706 CW_Subtype
: Entity_Id
;
6707 EQ_Typ
: Entity_Id
:= Empty
;
6710 -- A class-wide equivalent type is not needed on VM targets
6711 -- because the VM back-ends handle the class-wide object
6712 -- initialization itself (and doesn't need or want the
6713 -- additional intermediate type to handle the assignment).
6715 if Expander_Active
and then Tagged_Type_Expansion
then
6717 -- If this is the class-wide type of a completion that is a
6718 -- record subtype, set the type of the class-wide type to be
6719 -- the full base type, for use in the expanded code for the
6720 -- equivalent type. Should this be done earlier when the
6721 -- completion is analyzed ???
6723 if Is_Private_Type
(Etype
(Unc_Typ
))
6725 Ekind
(Full_View
(Etype
(Unc_Typ
))) = E_Record_Subtype
6727 Set_Etype
(Unc_Typ
, Base_Type
(Full_View
(Etype
(Unc_Typ
))));
6730 EQ_Typ
:= Make_CW_Equivalent_Type
(Unc_Typ
, E
);
6733 CW_Subtype
:= New_Class_Wide_Subtype
(Unc_Typ
, E
);
6734 Set_Equivalent_Type
(CW_Subtype
, EQ_Typ
);
6735 Set_Cloned_Subtype
(CW_Subtype
, Base_Type
(Unc_Typ
));
6737 return New_Occurrence_Of
(CW_Subtype
, Loc
);
6740 -- Indefinite record type with discriminants
6743 D
:= First_Discriminant
(Unc_Typ
);
6744 while Present
(D
) loop
6745 Append_To
(List_Constr
,
6746 Make_Selected_Component
(Loc
,
6747 Prefix
=> Duplicate_Subexpr_No_Checks
(E
),
6748 Selector_Name
=> New_Occurrence_Of
(D
, Loc
)));
6750 Next_Discriminant
(D
);
6755 Make_Subtype_Indication
(Loc
,
6756 Subtype_Mark
=> New_Occurrence_Of
(Unc_Typ
, Loc
),
6758 Make_Index_Or_Discriminant_Constraint
(Loc
,
6759 Constraints
=> List_Constr
));
6760 end Make_Subtype_From_Expr
;
6762 ----------------------------
6763 -- Matching_Standard_Type --
6764 ----------------------------
6766 function Matching_Standard_Type
(Typ
: Entity_Id
) return Entity_Id
is
6767 pragma Assert
(Is_Scalar_Type
(Typ
));
6768 Siz
: constant Uint
:= Esize
(Typ
);
6771 -- Floating-point cases
6773 if Is_Floating_Point_Type
(Typ
) then
6774 if Siz
<= Esize
(Standard_Short_Float
) then
6775 return Standard_Short_Float
;
6776 elsif Siz
<= Esize
(Standard_Float
) then
6777 return Standard_Float
;
6778 elsif Siz
<= Esize
(Standard_Long_Float
) then
6779 return Standard_Long_Float
;
6780 elsif Siz
<= Esize
(Standard_Long_Long_Float
) then
6781 return Standard_Long_Long_Float
;
6783 raise Program_Error
;
6786 -- Integer cases (includes fixed-point types)
6788 -- Unsigned integer cases (includes normal enumeration types)
6790 elsif Is_Unsigned_Type
(Typ
) then
6791 if Siz
<= Esize
(Standard_Short_Short_Unsigned
) then
6792 return Standard_Short_Short_Unsigned
;
6793 elsif Siz
<= Esize
(Standard_Short_Unsigned
) then
6794 return Standard_Short_Unsigned
;
6795 elsif Siz
<= Esize
(Standard_Unsigned
) then
6796 return Standard_Unsigned
;
6797 elsif Siz
<= Esize
(Standard_Long_Unsigned
) then
6798 return Standard_Long_Unsigned
;
6799 elsif Siz
<= Esize
(Standard_Long_Long_Unsigned
) then
6800 return Standard_Long_Long_Unsigned
;
6802 raise Program_Error
;
6805 -- Signed integer cases
6808 if Siz
<= Esize
(Standard_Short_Short_Integer
) then
6809 return Standard_Short_Short_Integer
;
6810 elsif Siz
<= Esize
(Standard_Short_Integer
) then
6811 return Standard_Short_Integer
;
6812 elsif Siz
<= Esize
(Standard_Integer
) then
6813 return Standard_Integer
;
6814 elsif Siz
<= Esize
(Standard_Long_Integer
) then
6815 return Standard_Long_Integer
;
6816 elsif Siz
<= Esize
(Standard_Long_Long_Integer
) then
6817 return Standard_Long_Long_Integer
;
6819 raise Program_Error
;
6822 end Matching_Standard_Type
;
6824 -----------------------------
6825 -- May_Generate_Large_Temp --
6826 -----------------------------
6828 -- At the current time, the only types that we return False for (i.e. where
6829 -- we decide we know they cannot generate large temps) are ones where we
6830 -- know the size is 256 bits or less at compile time, and we are still not
6831 -- doing a thorough job on arrays and records ???
6833 function May_Generate_Large_Temp
(Typ
: Entity_Id
) return Boolean is
6835 if not Size_Known_At_Compile_Time
(Typ
) then
6838 elsif Esize
(Typ
) /= 0 and then Esize
(Typ
) <= 256 then
6841 elsif Is_Array_Type
(Typ
)
6842 and then Present
(Packed_Array_Impl_Type
(Typ
))
6844 return May_Generate_Large_Temp
(Packed_Array_Impl_Type
(Typ
));
6846 -- We could do more here to find other small types ???
6851 end May_Generate_Large_Temp
;
6853 ------------------------
6854 -- Needs_Finalization --
6855 ------------------------
6857 function Needs_Finalization
(T
: Entity_Id
) return Boolean is
6858 function Has_Some_Controlled_Component
(Rec
: Entity_Id
) return Boolean;
6859 -- If type is not frozen yet, check explicitly among its components,
6860 -- because the Has_Controlled_Component flag is not necessarily set.
6862 -----------------------------------
6863 -- Has_Some_Controlled_Component --
6864 -----------------------------------
6866 function Has_Some_Controlled_Component
6867 (Rec
: Entity_Id
) return Boolean
6872 if Has_Controlled_Component
(Rec
) then
6875 elsif not Is_Frozen
(Rec
) then
6876 if Is_Record_Type
(Rec
) then
6877 Comp
:= First_Entity
(Rec
);
6879 while Present
(Comp
) loop
6880 if not Is_Type
(Comp
)
6881 and then Needs_Finalization
(Etype
(Comp
))
6891 elsif Is_Array_Type
(Rec
) then
6892 return Needs_Finalization
(Component_Type
(Rec
));
6895 return Has_Controlled_Component
(Rec
);
6900 end Has_Some_Controlled_Component
;
6902 -- Start of processing for Needs_Finalization
6905 -- Certain run-time configurations and targets do not provide support
6906 -- for controlled types.
6908 if Restriction_Active
(No_Finalization
) then
6911 -- C++ types are not considered controlled. It is assumed that the
6912 -- non-Ada side will handle their clean up.
6914 elsif Convention
(T
) = Convention_CPP
then
6917 -- Never needs finalization if Disable_Controlled set
6919 elsif Disable_Controlled
(T
) then
6923 -- Class-wide types are treated as controlled because derivations
6924 -- from the root type can introduce controlled components.
6926 return Is_Class_Wide_Type
(T
)
6927 or else Is_Controlled
(T
)
6928 or else Has_Controlled_Component
(T
)
6929 or else Has_Some_Controlled_Component
(T
)
6931 (Is_Concurrent_Type
(T
)
6932 and then Present
(Corresponding_Record_Type
(T
))
6933 and then Needs_Finalization
(Corresponding_Record_Type
(T
)));
6935 end Needs_Finalization
;
6937 ----------------------------
6938 -- Needs_Constant_Address --
6939 ----------------------------
6941 function Needs_Constant_Address
6943 Typ
: Entity_Id
) return Boolean
6947 -- If we have no initialization of any kind, then we don't need to place
6948 -- any restrictions on the address clause, because the object will be
6949 -- elaborated after the address clause is evaluated. This happens if the
6950 -- declaration has no initial expression, or the type has no implicit
6951 -- initialization, or the object is imported.
6953 -- The same holds for all initialized scalar types and all access types.
6954 -- Packed bit arrays of size up to 64 are represented using a modular
6955 -- type with an initialization (to zero) and can be processed like other
6956 -- initialized scalar types.
6958 -- If the type is controlled, code to attach the object to a
6959 -- finalization chain is generated at the point of declaration, and
6960 -- therefore the elaboration of the object cannot be delayed: the
6961 -- address expression must be a constant.
6963 if No
(Expression
(Decl
))
6964 and then not Needs_Finalization
(Typ
)
6966 (not Has_Non_Null_Base_Init_Proc
(Typ
)
6967 or else Is_Imported
(Defining_Identifier
(Decl
)))
6971 elsif (Present
(Expression
(Decl
)) and then Is_Scalar_Type
(Typ
))
6972 or else Is_Access_Type
(Typ
)
6974 (Is_Bit_Packed_Array
(Typ
)
6975 and then Is_Modular_Integer_Type
(Packed_Array_Impl_Type
(Typ
)))
6981 -- Otherwise, we require the address clause to be constant because
6982 -- the call to the initialization procedure (or the attach code) has
6983 -- to happen at the point of the declaration.
6985 -- Actually the IP call has been moved to the freeze actions anyway,
6986 -- so maybe we can relax this restriction???
6990 end Needs_Constant_Address
;
6992 ----------------------------
6993 -- New_Class_Wide_Subtype --
6994 ----------------------------
6996 function New_Class_Wide_Subtype
6997 (CW_Typ
: Entity_Id
;
6998 N
: Node_Id
) return Entity_Id
7000 Res
: constant Entity_Id
:= Create_Itype
(E_Void
, N
);
7001 Res_Name
: constant Name_Id
:= Chars
(Res
);
7002 Res_Scope
: constant Entity_Id
:= Scope
(Res
);
7005 Copy_Node
(CW_Typ
, Res
);
7006 Set_Comes_From_Source
(Res
, False);
7007 Set_Sloc
(Res
, Sloc
(N
));
7009 Set_Associated_Node_For_Itype
(Res
, N
);
7010 Set_Is_Public
(Res
, False); -- By default, may be changed below.
7011 Set_Public_Status
(Res
);
7012 Set_Chars
(Res
, Res_Name
);
7013 Set_Scope
(Res
, Res_Scope
);
7014 Set_Ekind
(Res
, E_Class_Wide_Subtype
);
7015 Set_Next_Entity
(Res
, Empty
);
7016 Set_Etype
(Res
, Base_Type
(CW_Typ
));
7017 Set_Is_Frozen
(Res
, False);
7018 Set_Freeze_Node
(Res
, Empty
);
7020 end New_Class_Wide_Subtype
;
7022 --------------------------------
7023 -- Non_Limited_Designated_Type --
7024 ---------------------------------
7026 function Non_Limited_Designated_Type
(T
: Entity_Id
) return Entity_Id
is
7027 Desig
: constant Entity_Id
:= Designated_Type
(T
);
7029 if Has_Non_Limited_View
(Desig
) then
7030 return Non_Limited_View
(Desig
);
7034 end Non_Limited_Designated_Type
;
7036 -----------------------------------
7037 -- OK_To_Do_Constant_Replacement --
7038 -----------------------------------
7040 function OK_To_Do_Constant_Replacement
(E
: Entity_Id
) return Boolean is
7041 ES
: constant Entity_Id
:= Scope
(E
);
7045 -- Do not replace statically allocated objects, because they may be
7046 -- modified outside the current scope.
7048 if Is_Statically_Allocated
(E
) then
7051 -- Do not replace aliased or volatile objects, since we don't know what
7052 -- else might change the value.
7054 elsif Is_Aliased
(E
) or else Treat_As_Volatile
(E
) then
7057 -- Debug flag -gnatdM disconnects this optimization
7059 elsif Debug_Flag_MM
then
7062 -- Otherwise check scopes
7065 CS
:= Current_Scope
;
7068 -- If we are in right scope, replacement is safe
7073 -- Packages do not affect the determination of safety
7075 elsif Ekind
(CS
) = E_Package
then
7076 exit when CS
= Standard_Standard
;
7079 -- Blocks do not affect the determination of safety
7081 elsif Ekind
(CS
) = E_Block
then
7084 -- Loops do not affect the determination of safety. Note that we
7085 -- kill all current values on entry to a loop, so we are just
7086 -- talking about processing within a loop here.
7088 elsif Ekind
(CS
) = E_Loop
then
7091 -- Otherwise, the reference is dubious, and we cannot be sure that
7092 -- it is safe to do the replacement.
7101 end OK_To_Do_Constant_Replacement
;
7103 ------------------------------------
7104 -- Possible_Bit_Aligned_Component --
7105 ------------------------------------
7107 function Possible_Bit_Aligned_Component
(N
: Node_Id
) return Boolean is
7109 -- Do not process an unanalyzed node because it is not yet decorated and
7110 -- most checks performed below will fail.
7112 if not Analyzed
(N
) then
7118 -- Case of indexed component
7120 when N_Indexed_Component
=>
7122 P
: constant Node_Id
:= Prefix
(N
);
7123 Ptyp
: constant Entity_Id
:= Etype
(P
);
7126 -- If we know the component size and it is less than 64, then
7127 -- we are definitely OK. The back end always does assignment of
7128 -- misaligned small objects correctly.
7130 if Known_Static_Component_Size
(Ptyp
)
7131 and then Component_Size
(Ptyp
) <= 64
7135 -- Otherwise, we need to test the prefix, to see if we are
7136 -- indexing from a possibly unaligned component.
7139 return Possible_Bit_Aligned_Component
(P
);
7143 -- Case of selected component
7145 when N_Selected_Component
=>
7147 P
: constant Node_Id
:= Prefix
(N
);
7148 Comp
: constant Entity_Id
:= Entity
(Selector_Name
(N
));
7151 -- If there is no component clause, then we are in the clear
7152 -- since the back end will never misalign a large component
7153 -- unless it is forced to do so. In the clear means we need
7154 -- only the recursive test on the prefix.
7156 if Component_May_Be_Bit_Aligned
(Comp
) then
7159 return Possible_Bit_Aligned_Component
(P
);
7163 -- For a slice, test the prefix, if that is possibly misaligned,
7164 -- then for sure the slice is.
7167 return Possible_Bit_Aligned_Component
(Prefix
(N
));
7169 -- For an unchecked conversion, check whether the expression may
7172 when N_Unchecked_Type_Conversion
=>
7173 return Possible_Bit_Aligned_Component
(Expression
(N
));
7175 -- If we have none of the above, it means that we have fallen off the
7176 -- top testing prefixes recursively, and we now have a stand alone
7177 -- object, where we don't have a problem, unless this is a renaming,
7178 -- in which case we need to look into the renamed object.
7181 if Is_Entity_Name
(N
)
7182 and then Present
(Renamed_Object
(Entity
(N
)))
7185 Possible_Bit_Aligned_Component
(Renamed_Object
(Entity
(N
)));
7191 end Possible_Bit_Aligned_Component
;
7193 -----------------------------------------------
7194 -- Process_Statements_For_Controlled_Objects --
7195 -----------------------------------------------
7197 procedure Process_Statements_For_Controlled_Objects
(N
: Node_Id
) is
7198 Loc
: constant Source_Ptr
:= Sloc
(N
);
7200 function Are_Wrapped
(L
: List_Id
) return Boolean;
7201 -- Determine whether list L contains only one statement which is a block
7203 function Wrap_Statements_In_Block
7205 Scop
: Entity_Id
:= Current_Scope
) return Node_Id
;
7206 -- Given a list of statements L, wrap it in a block statement and return
7207 -- the generated node. Scop is either the current scope or the scope of
7208 -- the context (if applicable).
7214 function Are_Wrapped
(L
: List_Id
) return Boolean is
7215 Stmt
: constant Node_Id
:= First
(L
);
7219 and then No
(Next
(Stmt
))
7220 and then Nkind
(Stmt
) = N_Block_Statement
;
7223 ------------------------------
7224 -- Wrap_Statements_In_Block --
7225 ------------------------------
7227 function Wrap_Statements_In_Block
7229 Scop
: Entity_Id
:= Current_Scope
) return Node_Id
7231 Block_Id
: Entity_Id
;
7232 Block_Nod
: Node_Id
;
7233 Iter_Loop
: Entity_Id
;
7237 Make_Block_Statement
(Loc
,
7238 Declarations
=> No_List
,
7239 Handled_Statement_Sequence
=>
7240 Make_Handled_Sequence_Of_Statements
(Loc
,
7243 -- Create a label for the block in case the block needs to manage the
7244 -- secondary stack. A label allows for flag Uses_Sec_Stack to be set.
7246 Add_Block_Identifier
(Block_Nod
, Block_Id
);
7248 -- When wrapping the statements of an iterator loop, check whether
7249 -- the loop requires secondary stack management and if so, propagate
7250 -- the appropriate flags to the block. This ensures that the cursor
7251 -- is properly cleaned up at each iteration of the loop.
7253 Iter_Loop
:= Find_Enclosing_Iterator_Loop
(Scop
);
7255 if Present
(Iter_Loop
) then
7256 Set_Uses_Sec_Stack
(Block_Id
, Uses_Sec_Stack
(Iter_Loop
));
7258 -- Secondary stack reclamation is suppressed when the associated
7259 -- iterator loop contains a return statement which uses the stack.
7261 Set_Sec_Stack_Needed_For_Return
7262 (Block_Id
, Sec_Stack_Needed_For_Return
(Iter_Loop
));
7266 end Wrap_Statements_In_Block
;
7272 -- Start of processing for Process_Statements_For_Controlled_Objects
7275 -- Whenever a non-handled statement list is wrapped in a block, the
7276 -- block must be explicitly analyzed to redecorate all entities in the
7277 -- list and ensure that a finalizer is properly built.
7282 N_Conditional_Entry_Call |
7283 N_Selective_Accept
=>
7285 -- Check the "then statements" for elsif parts and if statements
7287 if Nkind_In
(N
, N_Elsif_Part
, N_If_Statement
)
7288 and then not Is_Empty_List
(Then_Statements
(N
))
7289 and then not Are_Wrapped
(Then_Statements
(N
))
7290 and then Requires_Cleanup_Actions
7291 (Then_Statements
(N
), False, False)
7293 Block
:= Wrap_Statements_In_Block
(Then_Statements
(N
));
7294 Set_Then_Statements
(N
, New_List
(Block
));
7299 -- Check the "else statements" for conditional entry calls, if
7300 -- statements and selective accepts.
7302 if Nkind_In
(N
, N_Conditional_Entry_Call
,
7305 and then not Is_Empty_List
(Else_Statements
(N
))
7306 and then not Are_Wrapped
(Else_Statements
(N
))
7307 and then Requires_Cleanup_Actions
7308 (Else_Statements
(N
), False, False)
7310 Block
:= Wrap_Statements_In_Block
(Else_Statements
(N
));
7311 Set_Else_Statements
(N
, New_List
(Block
));
7316 when N_Abortable_Part |
7317 N_Accept_Alternative |
7318 N_Case_Statement_Alternative |
7319 N_Delay_Alternative |
7320 N_Entry_Call_Alternative |
7321 N_Exception_Handler |
7323 N_Triggering_Alternative
=>
7325 if not Is_Empty_List
(Statements
(N
))
7326 and then not Are_Wrapped
(Statements
(N
))
7327 and then Requires_Cleanup_Actions
(Statements
(N
), False, False)
7329 if Nkind
(N
) = N_Loop_Statement
7330 and then Present
(Identifier
(N
))
7333 Wrap_Statements_In_Block
7334 (L
=> Statements
(N
),
7335 Scop
=> Entity
(Identifier
(N
)));
7337 Block
:= Wrap_Statements_In_Block
(Statements
(N
));
7340 Set_Statements
(N
, New_List
(Block
));
7347 end Process_Statements_For_Controlled_Objects
;
7353 function Power_Of_Two
(N
: Node_Id
) return Nat
is
7354 Typ
: constant Entity_Id
:= Etype
(N
);
7355 pragma Assert
(Is_Integer_Type
(Typ
));
7357 Siz
: constant Nat
:= UI_To_Int
(Esize
(Typ
));
7361 if not Compile_Time_Known_Value
(N
) then
7365 Val
:= Expr_Value
(N
);
7366 for J
in 1 .. Siz
- 1 loop
7367 if Val
= Uint_2
** J
then
7376 ----------------------
7377 -- Remove_Init_Call --
7378 ----------------------
7380 function Remove_Init_Call
7382 Rep_Clause
: Node_Id
) return Node_Id
7384 Par
: constant Node_Id
:= Parent
(Var
);
7385 Typ
: constant Entity_Id
:= Etype
(Var
);
7387 Init_Proc
: Entity_Id
;
7388 -- Initialization procedure for Typ
7390 function Find_Init_Call_In_List
(From
: Node_Id
) return Node_Id
;
7391 -- Look for init call for Var starting at From and scanning the
7392 -- enclosing list until Rep_Clause or the end of the list is reached.
7394 ----------------------------
7395 -- Find_Init_Call_In_List --
7396 ----------------------------
7398 function Find_Init_Call_In_List
(From
: Node_Id
) return Node_Id
is
7399 Init_Call
: Node_Id
;
7403 while Present
(Init_Call
) and then Init_Call
/= Rep_Clause
loop
7404 if Nkind
(Init_Call
) = N_Procedure_Call_Statement
7405 and then Is_Entity_Name
(Name
(Init_Call
))
7406 and then Entity
(Name
(Init_Call
)) = Init_Proc
7415 end Find_Init_Call_In_List
;
7417 Init_Call
: Node_Id
;
7419 -- Start of processing for Find_Init_Call
7422 if Present
(Initialization_Statements
(Var
)) then
7423 Init_Call
:= Initialization_Statements
(Var
);
7424 Set_Initialization_Statements
(Var
, Empty
);
7426 elsif not Has_Non_Null_Base_Init_Proc
(Typ
) then
7428 -- No init proc for the type, so obviously no call to be found
7433 -- We might be able to handle other cases below by just properly
7434 -- setting Initialization_Statements at the point where the init proc
7435 -- call is generated???
7437 Init_Proc
:= Base_Init_Proc
(Typ
);
7439 -- First scan the list containing the declaration of Var
7441 Init_Call
:= Find_Init_Call_In_List
(From
=> Next
(Par
));
7443 -- If not found, also look on Var's freeze actions list, if any,
7444 -- since the init call may have been moved there (case of an address
7445 -- clause applying to Var).
7447 if No
(Init_Call
) and then Present
(Freeze_Node
(Var
)) then
7449 Find_Init_Call_In_List
(First
(Actions
(Freeze_Node
(Var
))));
7452 -- If the initialization call has actuals that use the secondary
7453 -- stack, the call may have been wrapped into a temporary block, in
7454 -- which case the block itself has to be removed.
7456 if No
(Init_Call
) and then Nkind
(Next
(Par
)) = N_Block_Statement
then
7458 Blk
: constant Node_Id
:= Next
(Par
);
7461 (Find_Init_Call_In_List
7462 (First
(Statements
(Handled_Statement_Sequence
(Blk
)))))
7470 if Present
(Init_Call
) then
7474 end Remove_Init_Call
;
7476 -------------------------
7477 -- Remove_Side_Effects --
7478 -------------------------
7480 procedure Remove_Side_Effects
7482 Name_Req
: Boolean := False;
7483 Renaming_Req
: Boolean := False;
7484 Variable_Ref
: Boolean := False;
7485 Related_Id
: Entity_Id
:= Empty
;
7486 Is_Low_Bound
: Boolean := False;
7487 Is_High_Bound
: Boolean := False)
7489 function Build_Temporary
7492 Related_Nod
: Node_Id
:= Empty
) return Entity_Id
;
7493 -- Create an external symbol of the form xxx_FIRST/_LAST if Related_Nod
7494 -- is present (xxx is taken from the Chars field of Related_Nod),
7495 -- otherwise it generates an internal temporary.
7497 function Is_Name_Reference
(N
: Node_Id
) return Boolean;
7498 -- Determine if the tree referenced by N represents a name. This is
7499 -- similar to Is_Object_Reference but returns true only if N can be
7500 -- renamed without the need for a temporary, the typical example of
7501 -- an object not in this category being a function call.
7503 ---------------------
7504 -- Build_Temporary --
7505 ---------------------
7507 function Build_Temporary
7510 Related_Nod
: Node_Id
:= Empty
) return Entity_Id
7515 -- The context requires an external symbol
7517 if Present
(Related_Id
) then
7518 if Is_Low_Bound
then
7519 Temp_Nam
:= New_External_Name
(Chars
(Related_Id
), "_FIRST");
7520 else pragma Assert
(Is_High_Bound
);
7521 Temp_Nam
:= New_External_Name
(Chars
(Related_Id
), "_LAST");
7524 return Make_Defining_Identifier
(Loc
, Temp_Nam
);
7526 -- Otherwise generate an internal temporary
7529 return Make_Temporary
(Loc
, Id
, Related_Nod
);
7531 end Build_Temporary
;
7533 -----------------------
7534 -- Is_Name_Reference --
7535 -----------------------
7537 function Is_Name_Reference
(N
: Node_Id
) return Boolean is
7539 if Is_Entity_Name
(N
) then
7540 return Present
(Entity
(N
)) and then Is_Object
(Entity
(N
));
7544 when N_Indexed_Component | N_Slice
=>
7546 Is_Name_Reference
(Prefix
(N
))
7547 or else Is_Access_Type
(Etype
(Prefix
(N
)));
7549 -- Attributes 'Input, 'Old and 'Result produce objects
7551 when N_Attribute_Reference
=>
7554 (Attribute_Name
(N
), Name_Input
, Name_Old
, Name_Result
);
7556 when N_Selected_Component
=>
7558 Is_Name_Reference
(Selector_Name
(N
))
7560 (Is_Name_Reference
(Prefix
(N
))
7561 or else Is_Access_Type
(Etype
(Prefix
(N
))));
7563 when N_Explicit_Dereference
=>
7566 -- A view conversion of a tagged name is a name reference
7568 when N_Type_Conversion
=>
7569 return Is_Tagged_Type
(Etype
(Subtype_Mark
(N
)))
7570 and then Is_Tagged_Type
(Etype
(Expression
(N
)))
7571 and then Is_Name_Reference
(Expression
(N
));
7573 -- An unchecked type conversion is considered to be a name if
7574 -- the operand is a name (this construction arises only as a
7575 -- result of expansion activities).
7577 when N_Unchecked_Type_Conversion
=>
7578 return Is_Name_Reference
(Expression
(N
));
7583 end Is_Name_Reference
;
7587 Loc
: constant Source_Ptr
:= Sloc
(Exp
);
7588 Exp_Type
: constant Entity_Id
:= Etype
(Exp
);
7589 Svg_Suppress
: constant Suppress_Record
:= Scope_Suppress
;
7593 Ptr_Typ_Decl
: Node_Id
;
7594 Ref_Type
: Entity_Id
;
7597 -- Start of processing for Remove_Side_Effects
7600 -- Handle cases in which there is nothing to do. In GNATprove mode,
7601 -- removal of side effects is useful for the light expansion of
7602 -- renamings. This removal should only occur when not inside a
7603 -- generic and not doing a pre-analysis.
7605 if not Expander_Active
7606 and (Inside_A_Generic
or not Full_Analysis
or not GNATprove_Mode
)
7611 -- Cannot generate temporaries if the invocation to remove side effects
7612 -- was issued too early and the type of the expression is not resolved
7613 -- (this happens because routines Duplicate_Subexpr_XX implicitly invoke
7614 -- Remove_Side_Effects).
7616 if No
(Exp_Type
) or else Ekind
(Exp_Type
) = E_Access_Attribute_Type
then
7619 -- No action needed for side-effect free expressions
7621 elsif Side_Effect_Free
(Exp
, Name_Req
, Variable_Ref
) then
7625 -- The remaining processing is done with all checks suppressed
7627 -- Note: from now on, don't use return statements, instead do a goto
7628 -- Leave, to ensure that we properly restore Scope_Suppress.Suppress.
7630 Scope_Suppress
.Suppress
:= (others => True);
7632 -- If it is an elementary type and we need to capture the value, just
7633 -- make a constant. Likewise if this is not a name reference, except
7634 -- for a type conversion because we would enter an infinite recursion
7635 -- with Checks.Apply_Predicate_Check if the target type has predicates.
7636 -- And type conversions need a specific treatment anyway, see below.
7637 -- Also do it if we have a volatile reference and Name_Req is not set
7638 -- (see comments for Side_Effect_Free).
7640 if Is_Elementary_Type
(Exp_Type
)
7641 and then (Variable_Ref
7642 or else (not Is_Name_Reference
(Exp
)
7643 and then Nkind
(Exp
) /= N_Type_Conversion
)
7644 or else (not Name_Req
7645 and then Is_Volatile_Reference
(Exp
)))
7647 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7648 Set_Etype
(Def_Id
, Exp_Type
);
7649 Res
:= New_Occurrence_Of
(Def_Id
, Loc
);
7651 -- If the expression is a packed reference, it must be reanalyzed and
7652 -- expanded, depending on context. This is the case for actuals where
7653 -- a constraint check may capture the actual before expansion of the
7654 -- call is complete.
7656 if Nkind
(Exp
) = N_Indexed_Component
7657 and then Is_Packed
(Etype
(Prefix
(Exp
)))
7659 Set_Analyzed
(Exp
, False);
7660 Set_Analyzed
(Prefix
(Exp
), False);
7664 -- Rnn : Exp_Type renames Expr;
7666 if Renaming_Req
then
7668 Make_Object_Renaming_Declaration
(Loc
,
7669 Defining_Identifier
=> Def_Id
,
7670 Subtype_Mark
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7671 Name
=> Relocate_Node
(Exp
));
7674 -- Rnn : constant Exp_Type := Expr;
7678 Make_Object_Declaration
(Loc
,
7679 Defining_Identifier
=> Def_Id
,
7680 Object_Definition
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7681 Constant_Present
=> True,
7682 Expression
=> Relocate_Node
(Exp
));
7684 Set_Assignment_OK
(E
);
7687 Insert_Action
(Exp
, E
);
7689 -- If the expression has the form v.all then we can just capture the
7690 -- pointer, and then do an explicit dereference on the result, but
7691 -- this is not right if this is a volatile reference.
7693 elsif Nkind
(Exp
) = N_Explicit_Dereference
7694 and then not Is_Volatile_Reference
(Exp
)
7696 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7698 Make_Explicit_Dereference
(Loc
, New_Occurrence_Of
(Def_Id
, Loc
));
7701 Make_Object_Declaration
(Loc
,
7702 Defining_Identifier
=> Def_Id
,
7703 Object_Definition
=>
7704 New_Occurrence_Of
(Etype
(Prefix
(Exp
)), Loc
),
7705 Constant_Present
=> True,
7706 Expression
=> Relocate_Node
(Prefix
(Exp
))));
7708 -- Similar processing for an unchecked conversion of an expression of
7709 -- the form v.all, where we want the same kind of treatment.
7711 elsif Nkind
(Exp
) = N_Unchecked_Type_Conversion
7712 and then Nkind
(Expression
(Exp
)) = N_Explicit_Dereference
7714 Remove_Side_Effects
(Expression
(Exp
), Name_Req
, Variable_Ref
);
7717 -- If this is a type conversion, leave the type conversion and remove
7718 -- the side effects in the expression. This is important in several
7719 -- circumstances: for change of representations, and also when this is a
7720 -- view conversion to a smaller object, where gigi can end up creating
7721 -- its own temporary of the wrong size.
7723 elsif Nkind
(Exp
) = N_Type_Conversion
then
7724 Remove_Side_Effects
(Expression
(Exp
), Name_Req
, Variable_Ref
);
7727 -- If this is an unchecked conversion that Gigi can't handle, make
7728 -- a copy or a use a renaming to capture the value.
7730 elsif Nkind
(Exp
) = N_Unchecked_Type_Conversion
7731 and then not Safe_Unchecked_Type_Conversion
(Exp
)
7733 if CW_Or_Has_Controlled_Part
(Exp_Type
) then
7735 -- Use a renaming to capture the expression, rather than create
7736 -- a controlled temporary.
7738 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7739 Res
:= New_Occurrence_Of
(Def_Id
, Loc
);
7742 Make_Object_Renaming_Declaration
(Loc
,
7743 Defining_Identifier
=> Def_Id
,
7744 Subtype_Mark
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7745 Name
=> Relocate_Node
(Exp
)));
7748 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7749 Set_Etype
(Def_Id
, Exp_Type
);
7750 Res
:= New_Occurrence_Of
(Def_Id
, Loc
);
7753 Make_Object_Declaration
(Loc
,
7754 Defining_Identifier
=> Def_Id
,
7755 Object_Definition
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7756 Constant_Present
=> not Is_Variable
(Exp
),
7757 Expression
=> Relocate_Node
(Exp
));
7759 Set_Assignment_OK
(E
);
7760 Insert_Action
(Exp
, E
);
7763 -- For expressions that denote names, we can use a renaming scheme.
7764 -- This is needed for correctness in the case of a volatile object of
7765 -- a non-volatile type because the Make_Reference call of the "default"
7766 -- approach would generate an illegal access value (an access value
7767 -- cannot designate such an object - see Analyze_Reference).
7769 elsif Is_Name_Reference
(Exp
)
7771 -- We skip using this scheme if we have an object of a volatile
7772 -- type and we do not have Name_Req set true (see comments for
7773 -- Side_Effect_Free).
7775 and then (Name_Req
or else not Treat_As_Volatile
(Exp_Type
))
7777 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7778 Res
:= New_Occurrence_Of
(Def_Id
, Loc
);
7781 Make_Object_Renaming_Declaration
(Loc
,
7782 Defining_Identifier
=> Def_Id
,
7783 Subtype_Mark
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7784 Name
=> Relocate_Node
(Exp
)));
7786 -- If this is a packed reference, or a selected component with
7787 -- a non-standard representation, a reference to the temporary
7788 -- will be replaced by a copy of the original expression (see
7789 -- Exp_Ch2.Expand_Renaming). Otherwise the temporary must be
7790 -- elaborated by gigi, and is of course not to be replaced in-line
7791 -- by the expression it renames, which would defeat the purpose of
7792 -- removing the side-effect.
7794 if Nkind_In
(Exp
, N_Selected_Component
, N_Indexed_Component
)
7795 and then Has_Non_Standard_Rep
(Etype
(Prefix
(Exp
)))
7799 Set_Is_Renaming_Of_Object
(Def_Id
, False);
7802 -- Avoid generating a variable-sized temporary, by generating the
7803 -- reference just for the function call. The transformation could be
7804 -- refined to apply only when the array component is constrained by a
7807 elsif Nkind
(Exp
) = N_Selected_Component
7808 and then Nkind
(Prefix
(Exp
)) = N_Function_Call
7809 and then Is_Array_Type
(Exp_Type
)
7811 Remove_Side_Effects
(Prefix
(Exp
), Name_Req
, Variable_Ref
);
7814 -- Otherwise we generate a reference to the expression
7817 -- An expression which is in SPARK mode is considered side effect
7818 -- free if the resulting value is captured by a variable or a
7819 -- constant. Same reasoning when generating C code.
7820 -- Why can't we apply this test in general???
7822 if (GNATprove_Mode
or Generate_C_Code
)
7823 and then Nkind
(Parent
(Exp
)) = N_Object_Declaration
7828 -- Special processing for function calls that return a limited type.
7829 -- We need to build a declaration that will enable build-in-place
7830 -- expansion of the call. This is not done if the context is already
7831 -- an object declaration, to prevent infinite recursion.
7833 -- This is relevant only in Ada 2005 mode. In Ada 95 programs we have
7834 -- to accommodate functions returning limited objects by reference.
7836 if Ada_Version
>= Ada_2005
7837 and then Nkind
(Exp
) = N_Function_Call
7838 and then Is_Limited_View
(Etype
(Exp
))
7839 and then Nkind
(Parent
(Exp
)) /= N_Object_Declaration
7842 Obj
: constant Entity_Id
:= Make_Temporary
(Loc
, 'F', Exp
);
7847 Make_Object_Declaration
(Loc
,
7848 Defining_Identifier
=> Obj
,
7849 Object_Definition
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7850 Expression
=> Relocate_Node
(Exp
));
7852 Insert_Action
(Exp
, Decl
);
7853 Set_Etype
(Obj
, Exp_Type
);
7854 Rewrite
(Exp
, New_Occurrence_Of
(Obj
, Loc
));
7859 Def_Id
:= Build_Temporary
(Loc
, 'R', Exp
);
7861 -- The regular expansion of functions with side effects involves the
7862 -- generation of an access type to capture the return value found on
7863 -- the secondary stack. Since SPARK (and why) cannot process access
7864 -- types, use a different approach which ignores the secondary stack
7865 -- and "copies" the returned object.
7866 -- When generating C code, no need for a 'reference since the
7867 -- secondary stack is not supported.
7869 if GNATprove_Mode
or Generate_C_Code
then
7870 Res
:= New_Occurrence_Of
(Def_Id
, Loc
);
7871 Ref_Type
:= Exp_Type
;
7873 -- Regular expansion utilizing an access type and 'reference
7877 Make_Explicit_Dereference
(Loc
,
7878 Prefix
=> New_Occurrence_Of
(Def_Id
, Loc
));
7881 -- type Ann is access all <Exp_Type>;
7883 Ref_Type
:= Make_Temporary
(Loc
, 'A');
7886 Make_Full_Type_Declaration
(Loc
,
7887 Defining_Identifier
=> Ref_Type
,
7889 Make_Access_To_Object_Definition
(Loc
,
7890 All_Present
=> True,
7891 Subtype_Indication
=>
7892 New_Occurrence_Of
(Exp_Type
, Loc
)));
7894 Insert_Action
(Exp
, Ptr_Typ_Decl
);
7898 if Nkind
(E
) = N_Explicit_Dereference
then
7899 New_Exp
:= Relocate_Node
(Prefix
(E
));
7902 E
:= Relocate_Node
(E
);
7904 -- Do not generate a 'reference in SPARK mode or C generation
7905 -- since the access type is not created in the first place.
7907 if GNATprove_Mode
or Generate_C_Code
then
7910 -- Otherwise generate reference, marking the value as non-null
7911 -- since we know it cannot be null and we don't want a check.
7914 New_Exp
:= Make_Reference
(Loc
, E
);
7915 Set_Is_Known_Non_Null
(Def_Id
);
7919 if Is_Delayed_Aggregate
(E
) then
7921 -- The expansion of nested aggregates is delayed until the
7922 -- enclosing aggregate is expanded. As aggregates are often
7923 -- qualified, the predicate applies to qualified expressions as
7924 -- well, indicating that the enclosing aggregate has not been
7925 -- expanded yet. At this point the aggregate is part of a
7926 -- stand-alone declaration, and must be fully expanded.
7928 if Nkind
(E
) = N_Qualified_Expression
then
7929 Set_Expansion_Delayed
(Expression
(E
), False);
7930 Set_Analyzed
(Expression
(E
), False);
7932 Set_Expansion_Delayed
(E
, False);
7935 Set_Analyzed
(E
, False);
7939 Make_Object_Declaration
(Loc
,
7940 Defining_Identifier
=> Def_Id
,
7941 Object_Definition
=> New_Occurrence_Of
(Ref_Type
, Loc
),
7942 Constant_Present
=> True,
7943 Expression
=> New_Exp
));
7946 -- Preserve the Assignment_OK flag in all copies, since at least one
7947 -- copy may be used in a context where this flag must be set (otherwise
7948 -- why would the flag be set in the first place).
7950 Set_Assignment_OK
(Res
, Assignment_OK
(Exp
));
7952 -- Finally rewrite the original expression and we are done
7955 Analyze_And_Resolve
(Exp
, Exp_Type
);
7958 Scope_Suppress
:= Svg_Suppress
;
7959 end Remove_Side_Effects
;
7961 ---------------------------
7962 -- Represented_As_Scalar --
7963 ---------------------------
7965 function Represented_As_Scalar
(T
: Entity_Id
) return Boolean is
7966 UT
: constant Entity_Id
:= Underlying_Type
(T
);
7968 return Is_Scalar_Type
(UT
)
7969 or else (Is_Bit_Packed_Array
(UT
)
7970 and then Is_Scalar_Type
(Packed_Array_Impl_Type
(UT
)));
7971 end Represented_As_Scalar
;
7973 ------------------------------
7974 -- Requires_Cleanup_Actions --
7975 ------------------------------
7977 function Requires_Cleanup_Actions
7979 Lib_Level
: Boolean) return Boolean
7981 At_Lib_Level
: constant Boolean :=
7983 and then Nkind_In
(N
, N_Package_Body
,
7984 N_Package_Specification
);
7985 -- N is at the library level if the top-most context is a package and
7986 -- the path taken to reach N does not inlcude non-package constructs.
7990 when N_Accept_Statement |
7998 Requires_Cleanup_Actions
(Declarations
(N
), At_Lib_Level
, True)
8000 (Present
(Handled_Statement_Sequence
(N
))
8002 Requires_Cleanup_Actions
8003 (Statements
(Handled_Statement_Sequence
(N
)),
8004 At_Lib_Level
, True));
8006 when N_Package_Specification
=>
8008 Requires_Cleanup_Actions
8009 (Visible_Declarations
(N
), At_Lib_Level
, True)
8011 Requires_Cleanup_Actions
8012 (Private_Declarations
(N
), At_Lib_Level
, True);
8017 end Requires_Cleanup_Actions
;
8019 ------------------------------
8020 -- Requires_Cleanup_Actions --
8021 ------------------------------
8023 function Requires_Cleanup_Actions
8025 Lib_Level
: Boolean;
8026 Nested_Constructs
: Boolean) return Boolean
8031 Obj_Typ
: Entity_Id
;
8032 Pack_Id
: Entity_Id
;
8037 or else Is_Empty_List
(L
)
8043 while Present
(Decl
) loop
8045 -- Library-level tagged types
8047 if Nkind
(Decl
) = N_Full_Type_Declaration
then
8048 Typ
:= Defining_Identifier
(Decl
);
8050 -- Ignored Ghost types do not need any cleanup actions because
8051 -- they will not appear in the final tree.
8053 if Is_Ignored_Ghost_Entity
(Typ
) then
8056 elsif Is_Tagged_Type
(Typ
)
8057 and then Is_Library_Level_Entity
(Typ
)
8058 and then Convention
(Typ
) = Convention_Ada
8059 and then Present
(Access_Disp_Table
(Typ
))
8060 and then RTE_Available
(RE_Unregister_Tag
)
8061 and then not Is_Abstract_Type
(Typ
)
8062 and then not No_Run_Time_Mode
8067 -- Regular object declarations
8069 elsif Nkind
(Decl
) = N_Object_Declaration
then
8070 Obj_Id
:= Defining_Identifier
(Decl
);
8071 Obj_Typ
:= Base_Type
(Etype
(Obj_Id
));
8072 Expr
:= Expression
(Decl
);
8074 -- Bypass any form of processing for objects which have their
8075 -- finalization disabled. This applies only to objects at the
8078 if Lib_Level
and then Finalize_Storage_Only
(Obj_Typ
) then
8081 -- Transient variables are treated separately in order to minimize
8082 -- the size of the generated code. See Exp_Ch7.Process_Transient_
8085 elsif Is_Processed_Transient
(Obj_Id
) then
8088 -- Ignored Ghost objects do not need any cleanup actions because
8089 -- they will not appear in the final tree.
8091 elsif Is_Ignored_Ghost_Entity
(Obj_Id
) then
8094 -- The expansion of iterator loops generates an object declaration
8095 -- where the Ekind is explicitly set to loop parameter. This is to
8096 -- ensure that the loop parameter behaves as a constant from user
8097 -- code point of view. Such object are never controlled and do not
8098 -- require cleanup actions. An iterator loop over a container of
8099 -- controlled objects does not produce such object declarations.
8101 elsif Ekind
(Obj_Id
) = E_Loop_Parameter
then
8104 -- The object is of the form:
8105 -- Obj : Typ [:= Expr];
8107 -- Do not process the incomplete view of a deferred constant. Do
8108 -- not consider tag-to-class-wide conversions.
8110 elsif not Is_Imported
(Obj_Id
)
8111 and then Needs_Finalization
(Obj_Typ
)
8112 and then not (Ekind
(Obj_Id
) = E_Constant
8113 and then not Has_Completion
(Obj_Id
))
8114 and then not Is_Tag_To_Class_Wide_Conversion
(Obj_Id
)
8118 -- The object is of the form:
8119 -- Obj : Access_Typ := Non_BIP_Function_Call'reference;
8121 -- Obj : Access_Typ :=
8122 -- BIP_Function_Call (BIPalloc => 2, ...)'reference;
8124 elsif Is_Access_Type
(Obj_Typ
)
8125 and then Needs_Finalization
8126 (Available_View
(Designated_Type
(Obj_Typ
)))
8127 and then Present
(Expr
)
8129 (Is_Secondary_Stack_BIP_Func_Call
(Expr
)
8131 (Is_Non_BIP_Func_Call
(Expr
)
8132 and then not Is_Related_To_Func_Return
(Obj_Id
)))
8136 -- Processing for "hook" objects generated for controlled
8137 -- transients declared inside an Expression_With_Actions.
8139 elsif Is_Access_Type
(Obj_Typ
)
8140 and then Present
(Status_Flag_Or_Transient_Decl
(Obj_Id
))
8141 and then Nkind
(Status_Flag_Or_Transient_Decl
(Obj_Id
)) =
8142 N_Object_Declaration
8146 -- Processing for intermediate results of if expressions where
8147 -- one of the alternatives uses a controlled function call.
8149 elsif Is_Access_Type
(Obj_Typ
)
8150 and then Present
(Status_Flag_Or_Transient_Decl
(Obj_Id
))
8151 and then Nkind
(Status_Flag_Or_Transient_Decl
(Obj_Id
)) =
8152 N_Defining_Identifier
8153 and then Present
(Expr
)
8154 and then Nkind
(Expr
) = N_Null
8158 -- Simple protected objects which use type System.Tasking.
8159 -- Protected_Objects.Protection to manage their locks should be
8160 -- treated as controlled since they require manual cleanup.
8162 elsif Ekind
(Obj_Id
) = E_Variable
8163 and then (Is_Simple_Protected_Type
(Obj_Typ
)
8164 or else Has_Simple_Protected_Object
(Obj_Typ
))
8169 -- Specific cases of object renamings
8171 elsif Nkind
(Decl
) = N_Object_Renaming_Declaration
then
8172 Obj_Id
:= Defining_Identifier
(Decl
);
8173 Obj_Typ
:= Base_Type
(Etype
(Obj_Id
));
8175 -- Bypass any form of processing for objects which have their
8176 -- finalization disabled. This applies only to objects at the
8179 if Lib_Level
and then Finalize_Storage_Only
(Obj_Typ
) then
8182 -- Ignored Ghost object renamings do not need any cleanup actions
8183 -- because they will not appear in the final tree.
8185 elsif Is_Ignored_Ghost_Entity
(Obj_Id
) then
8188 -- Return object of a build-in-place function. This case is
8189 -- recognized and marked by the expansion of an extended return
8190 -- statement (see Expand_N_Extended_Return_Statement).
8192 elsif Needs_Finalization
(Obj_Typ
)
8193 and then Is_Return_Object
(Obj_Id
)
8194 and then Present
(Status_Flag_Or_Transient_Decl
(Obj_Id
))
8198 -- Detect a case where a source object has been initialized by
8199 -- a controlled function call or another object which was later
8200 -- rewritten as a class-wide conversion of Ada.Tags.Displace.
8202 -- Obj1 : CW_Type := Src_Obj;
8203 -- Obj2 : CW_Type := Function_Call (...);
8205 -- Obj1 : CW_Type renames (... Ada.Tags.Displace (Src_Obj));
8206 -- Tmp : ... := Function_Call (...)'reference;
8207 -- Obj2 : CW_Type renames (... Ada.Tags.Displace (Tmp));
8209 elsif Is_Displacement_Of_Object_Or_Function_Result
(Obj_Id
) then
8213 -- Inspect the freeze node of an access-to-controlled type and look
8214 -- for a delayed finalization master. This case arises when the
8215 -- freeze actions are inserted at a later time than the expansion of
8216 -- the context. Since Build_Finalizer is never called on a single
8217 -- construct twice, the master will be ultimately left out and never
8218 -- finalized. This is also needed for freeze actions of designated
8219 -- types themselves, since in some cases the finalization master is
8220 -- associated with a designated type's freeze node rather than that
8221 -- of the access type (see handling for freeze actions in
8222 -- Build_Finalization_Master).
8224 elsif Nkind
(Decl
) = N_Freeze_Entity
8225 and then Present
(Actions
(Decl
))
8227 Typ
:= Entity
(Decl
);
8229 -- Freeze nodes for ignored Ghost types do not need cleanup
8230 -- actions because they will never appear in the final tree.
8232 if Is_Ignored_Ghost_Entity
(Typ
) then
8235 elsif ((Is_Access_Type
(Typ
)
8236 and then not Is_Access_Subprogram_Type
(Typ
)
8237 and then Needs_Finalization
8238 (Available_View
(Designated_Type
(Typ
))))
8239 or else (Is_Type
(Typ
) and then Needs_Finalization
(Typ
)))
8240 and then Requires_Cleanup_Actions
8241 (Actions
(Decl
), Lib_Level
, Nested_Constructs
)
8246 -- Nested package declarations
8248 elsif Nested_Constructs
8249 and then Nkind
(Decl
) = N_Package_Declaration
8251 Pack_Id
:= Defining_Entity
(Decl
);
8253 -- Do not inspect an ignored Ghost package because all code found
8254 -- within will not appear in the final tree.
8256 if Is_Ignored_Ghost_Entity
(Pack_Id
) then
8259 elsif Ekind
(Pack_Id
) /= E_Generic_Package
8260 and then Requires_Cleanup_Actions
8261 (Specification
(Decl
), Lib_Level
)
8266 -- Nested package bodies
8268 elsif Nested_Constructs
and then Nkind
(Decl
) = N_Package_Body
then
8270 -- Do not inspect an ignored Ghost package body because all code
8271 -- found within will not appear in the final tree.
8273 if Is_Ignored_Ghost_Entity
(Defining_Entity
(Decl
)) then
8276 elsif Ekind
(Corresponding_Spec
(Decl
)) /= E_Generic_Package
8277 and then Requires_Cleanup_Actions
(Decl
, Lib_Level
)
8282 elsif Nkind
(Decl
) = N_Block_Statement
8285 -- Handle a rare case caused by a controlled transient variable
8286 -- created as part of a record init proc. The variable is wrapped
8287 -- in a block, but the block is not associated with a transient
8292 -- Handle the case where the original context has been wrapped in
8293 -- a block to avoid interference between exception handlers and
8294 -- At_End handlers. Treat the block as transparent and process its
8297 or else Is_Finalization_Wrapper
(Decl
))
8299 if Requires_Cleanup_Actions
(Decl
, Lib_Level
) then
8308 end Requires_Cleanup_Actions
;
8310 ------------------------------------
8311 -- Safe_Unchecked_Type_Conversion --
8312 ------------------------------------
8314 -- Note: this function knows quite a bit about the exact requirements of
8315 -- Gigi with respect to unchecked type conversions, and its code must be
8316 -- coordinated with any changes in Gigi in this area.
8318 -- The above requirements should be documented in Sinfo ???
8320 function Safe_Unchecked_Type_Conversion
(Exp
: Node_Id
) return Boolean is
8325 Pexp
: constant Node_Id
:= Parent
(Exp
);
8328 -- If the expression is the RHS of an assignment or object declaration
8329 -- we are always OK because there will always be a target.
8331 -- Object renaming declarations, (generated for view conversions of
8332 -- actuals in inlined calls), like object declarations, provide an
8333 -- explicit type, and are safe as well.
8335 if (Nkind
(Pexp
) = N_Assignment_Statement
8336 and then Expression
(Pexp
) = Exp
)
8337 or else Nkind_In
(Pexp
, N_Object_Declaration
,
8338 N_Object_Renaming_Declaration
)
8342 -- If the expression is the prefix of an N_Selected_Component we should
8343 -- also be OK because GCC knows to look inside the conversion except if
8344 -- the type is discriminated. We assume that we are OK anyway if the
8345 -- type is not set yet or if it is controlled since we can't afford to
8346 -- introduce a temporary in this case.
8348 elsif Nkind
(Pexp
) = N_Selected_Component
8349 and then Prefix
(Pexp
) = Exp
8351 if No
(Etype
(Pexp
)) then
8355 not Has_Discriminants
(Etype
(Pexp
))
8356 or else Is_Constrained
(Etype
(Pexp
));
8360 -- Set the output type, this comes from Etype if it is set, otherwise we
8361 -- take it from the subtype mark, which we assume was already fully
8364 if Present
(Etype
(Exp
)) then
8365 Otyp
:= Etype
(Exp
);
8367 Otyp
:= Entity
(Subtype_Mark
(Exp
));
8370 -- The input type always comes from the expression, and we assume this
8371 -- is indeed always analyzed, so we can simply get the Etype.
8373 Ityp
:= Etype
(Expression
(Exp
));
8375 -- Initialize alignments to unknown so far
8380 -- Replace a concurrent type by its corresponding record type and each
8381 -- type by its underlying type and do the tests on those. The original
8382 -- type may be a private type whose completion is a concurrent type, so
8383 -- find the underlying type first.
8385 if Present
(Underlying_Type
(Otyp
)) then
8386 Otyp
:= Underlying_Type
(Otyp
);
8389 if Present
(Underlying_Type
(Ityp
)) then
8390 Ityp
:= Underlying_Type
(Ityp
);
8393 if Is_Concurrent_Type
(Otyp
) then
8394 Otyp
:= Corresponding_Record_Type
(Otyp
);
8397 if Is_Concurrent_Type
(Ityp
) then
8398 Ityp
:= Corresponding_Record_Type
(Ityp
);
8401 -- If the base types are the same, we know there is no problem since
8402 -- this conversion will be a noop.
8404 if Implementation_Base_Type
(Otyp
) = Implementation_Base_Type
(Ityp
) then
8407 -- Same if this is an upwards conversion of an untagged type, and there
8408 -- are no constraints involved (could be more general???)
8410 elsif Etype
(Ityp
) = Otyp
8411 and then not Is_Tagged_Type
(Ityp
)
8412 and then not Has_Discriminants
(Ityp
)
8413 and then No
(First_Rep_Item
(Base_Type
(Ityp
)))
8417 -- If the expression has an access type (object or subprogram) we assume
8418 -- that the conversion is safe, because the size of the target is safe,
8419 -- even if it is a record (which might be treated as having unknown size
8422 elsif Is_Access_Type
(Ityp
) then
8425 -- If the size of output type is known at compile time, there is never
8426 -- a problem. Note that unconstrained records are considered to be of
8427 -- known size, but we can't consider them that way here, because we are
8428 -- talking about the actual size of the object.
8430 -- We also make sure that in addition to the size being known, we do not
8431 -- have a case which might generate an embarrassingly large temp in
8432 -- stack checking mode.
8434 elsif Size_Known_At_Compile_Time
(Otyp
)
8436 (not Stack_Checking_Enabled
8437 or else not May_Generate_Large_Temp
(Otyp
))
8438 and then not (Is_Record_Type
(Otyp
) and then not Is_Constrained
(Otyp
))
8442 -- If either type is tagged, then we know the alignment is OK so Gigi
8443 -- will be able to use pointer punning.
8445 elsif Is_Tagged_Type
(Otyp
) or else Is_Tagged_Type
(Ityp
) then
8448 -- If either type is a limited record type, we cannot do a copy, so say
8449 -- safe since there's nothing else we can do.
8451 elsif Is_Limited_Record
(Otyp
) or else Is_Limited_Record
(Ityp
) then
8454 -- Conversions to and from packed array types are always ignored and
8457 elsif Is_Packed_Array_Impl_Type
(Otyp
)
8458 or else Is_Packed_Array_Impl_Type
(Ityp
)
8463 -- The only other cases known to be safe is if the input type's
8464 -- alignment is known to be at least the maximum alignment for the
8465 -- target or if both alignments are known and the output type's
8466 -- alignment is no stricter than the input's. We can use the component
8467 -- type alignement for an array if a type is an unpacked array type.
8469 if Present
(Alignment_Clause
(Otyp
)) then
8470 Oalign
:= Expr_Value
(Expression
(Alignment_Clause
(Otyp
)));
8472 elsif Is_Array_Type
(Otyp
)
8473 and then Present
(Alignment_Clause
(Component_Type
(Otyp
)))
8475 Oalign
:= Expr_Value
(Expression
(Alignment_Clause
8476 (Component_Type
(Otyp
))));
8479 if Present
(Alignment_Clause
(Ityp
)) then
8480 Ialign
:= Expr_Value
(Expression
(Alignment_Clause
(Ityp
)));
8482 elsif Is_Array_Type
(Ityp
)
8483 and then Present
(Alignment_Clause
(Component_Type
(Ityp
)))
8485 Ialign
:= Expr_Value
(Expression
(Alignment_Clause
8486 (Component_Type
(Ityp
))));
8489 if Ialign
/= No_Uint
and then Ialign
> Maximum_Alignment
then
8492 elsif Ialign
/= No_Uint
8493 and then Oalign
/= No_Uint
8494 and then Ialign
<= Oalign
8498 -- Otherwise, Gigi cannot handle this and we must make a temporary
8503 end Safe_Unchecked_Type_Conversion
;
8505 ---------------------------------
8506 -- Set_Current_Value_Condition --
8507 ---------------------------------
8509 -- Note: the implementation of this procedure is very closely tied to the
8510 -- implementation of Get_Current_Value_Condition. Here we set required
8511 -- Current_Value fields, and in Get_Current_Value_Condition, we interpret
8512 -- them, so they must have a consistent view.
8514 procedure Set_Current_Value_Condition
(Cnode
: Node_Id
) is
8516 procedure Set_Entity_Current_Value
(N
: Node_Id
);
8517 -- If N is an entity reference, where the entity is of an appropriate
8518 -- kind, then set the current value of this entity to Cnode, unless
8519 -- there is already a definite value set there.
8521 procedure Set_Expression_Current_Value
(N
: Node_Id
);
8522 -- If N is of an appropriate form, sets an appropriate entry in current
8523 -- value fields of relevant entities. Multiple entities can be affected
8524 -- in the case of an AND or AND THEN.
8526 ------------------------------
8527 -- Set_Entity_Current_Value --
8528 ------------------------------
8530 procedure Set_Entity_Current_Value
(N
: Node_Id
) is
8532 if Is_Entity_Name
(N
) then
8534 Ent
: constant Entity_Id
:= Entity
(N
);
8537 -- Don't capture if not safe to do so
8539 if not Safe_To_Capture_Value
(N
, Ent
, Cond
=> True) then
8543 -- Here we have a case where the Current_Value field may need
8544 -- to be set. We set it if it is not already set to a compile
8545 -- time expression value.
8547 -- Note that this represents a decision that one condition
8548 -- blots out another previous one. That's certainly right if
8549 -- they occur at the same level. If the second one is nested,
8550 -- then the decision is neither right nor wrong (it would be
8551 -- equally OK to leave the outer one in place, or take the new
8552 -- inner one. Really we should record both, but our data
8553 -- structures are not that elaborate.
8555 if Nkind
(Current_Value
(Ent
)) not in N_Subexpr
then
8556 Set_Current_Value
(Ent
, Cnode
);
8560 end Set_Entity_Current_Value
;
8562 ----------------------------------
8563 -- Set_Expression_Current_Value --
8564 ----------------------------------
8566 procedure Set_Expression_Current_Value
(N
: Node_Id
) is
8572 -- Loop to deal with (ignore for now) any NOT operators present. The
8573 -- presence of NOT operators will be handled properly when we call
8574 -- Get_Current_Value_Condition.
8576 while Nkind
(Cond
) = N_Op_Not
loop
8577 Cond
:= Right_Opnd
(Cond
);
8580 -- For an AND or AND THEN, recursively process operands
8582 if Nkind
(Cond
) = N_Op_And
or else Nkind
(Cond
) = N_And_Then
then
8583 Set_Expression_Current_Value
(Left_Opnd
(Cond
));
8584 Set_Expression_Current_Value
(Right_Opnd
(Cond
));
8588 -- Check possible relational operator
8590 if Nkind
(Cond
) in N_Op_Compare
then
8591 if Compile_Time_Known_Value
(Right_Opnd
(Cond
)) then
8592 Set_Entity_Current_Value
(Left_Opnd
(Cond
));
8593 elsif Compile_Time_Known_Value
(Left_Opnd
(Cond
)) then
8594 Set_Entity_Current_Value
(Right_Opnd
(Cond
));
8597 elsif Nkind_In
(Cond
,
8599 N_Qualified_Expression
,
8600 N_Expression_With_Actions
)
8602 Set_Expression_Current_Value
(Expression
(Cond
));
8604 -- Check possible boolean variable reference
8607 Set_Entity_Current_Value
(Cond
);
8609 end Set_Expression_Current_Value
;
8611 -- Start of processing for Set_Current_Value_Condition
8614 Set_Expression_Current_Value
(Condition
(Cnode
));
8615 end Set_Current_Value_Condition
;
8617 --------------------------
8618 -- Set_Elaboration_Flag --
8619 --------------------------
8621 procedure Set_Elaboration_Flag
(N
: Node_Id
; Spec_Id
: Entity_Id
) is
8622 Loc
: constant Source_Ptr
:= Sloc
(N
);
8623 Ent
: constant Entity_Id
:= Elaboration_Entity
(Spec_Id
);
8627 if Present
(Ent
) then
8629 -- Nothing to do if at the compilation unit level, because in this
8630 -- case the flag is set by the binder generated elaboration routine.
8632 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
8635 -- Here we do need to generate an assignment statement
8638 Check_Restriction
(No_Elaboration_Code
, N
);
8640 Make_Assignment_Statement
(Loc
,
8641 Name
=> New_Occurrence_Of
(Ent
, Loc
),
8642 Expression
=> Make_Integer_Literal
(Loc
, Uint_1
));
8644 if Nkind
(Parent
(N
)) = N_Subunit
then
8645 Insert_After
(Corresponding_Stub
(Parent
(N
)), Asn
);
8647 Insert_After
(N
, Asn
);
8652 -- Kill current value indication. This is necessary because the
8653 -- tests of this flag are inserted out of sequence and must not
8654 -- pick up bogus indications of the wrong constant value.
8656 Set_Current_Value
(Ent
, Empty
);
8658 -- If the subprogram is in the current declarative part and
8659 -- 'access has been applied to it, generate an elaboration
8660 -- check at the beginning of the declarations of the body.
8662 if Nkind
(N
) = N_Subprogram_Body
8663 and then Address_Taken
(Spec_Id
)
8665 Ekind_In
(Scope
(Spec_Id
), E_Block
, E_Procedure
, E_Function
)
8668 Loc
: constant Source_Ptr
:= Sloc
(N
);
8669 Decls
: constant List_Id
:= Declarations
(N
);
8673 -- No need to generate this check if first entry in the
8674 -- declaration list is a raise of Program_Error now.
8677 and then Nkind
(First
(Decls
)) = N_Raise_Program_Error
8682 -- Otherwise generate the check
8685 Make_Raise_Program_Error
(Loc
,
8688 Left_Opnd
=> New_Occurrence_Of
(Ent
, Loc
),
8689 Right_Opnd
=> Make_Integer_Literal
(Loc
, Uint_0
)),
8690 Reason
=> PE_Access_Before_Elaboration
);
8693 Set_Declarations
(N
, New_List
(Chk
));
8695 Prepend
(Chk
, Decls
);
8703 end Set_Elaboration_Flag
;
8705 ----------------------------
8706 -- Set_Renamed_Subprogram --
8707 ----------------------------
8709 procedure Set_Renamed_Subprogram
(N
: Node_Id
; E
: Entity_Id
) is
8711 -- If input node is an identifier, we can just reset it
8713 if Nkind
(N
) = N_Identifier
then
8714 Set_Chars
(N
, Chars
(E
));
8717 -- Otherwise we have to do a rewrite, preserving Comes_From_Source
8721 CS
: constant Boolean := Comes_From_Source
(N
);
8723 Rewrite
(N
, Make_Identifier
(Sloc
(N
), Chars
(E
)));
8725 Set_Comes_From_Source
(N
, CS
);
8726 Set_Analyzed
(N
, True);
8729 end Set_Renamed_Subprogram
;
8731 ----------------------
8732 -- Side_Effect_Free --
8733 ----------------------
8735 function Side_Effect_Free
8737 Name_Req
: Boolean := False;
8738 Variable_Ref
: Boolean := False) return Boolean
8740 Typ
: constant Entity_Id
:= Etype
(N
);
8741 -- Result type of the expression
8743 function Safe_Prefixed_Reference
(N
: Node_Id
) return Boolean;
8744 -- The argument N is a construct where the Prefix is dereferenced if it
8745 -- is an access type and the result is a variable. The call returns True
8746 -- if the construct is side effect free (not considering side effects in
8747 -- other than the prefix which are to be tested by the caller).
8749 function Within_In_Parameter
(N
: Node_Id
) return Boolean;
8750 -- Determines if N is a subcomponent of a composite in-parameter. If so,
8751 -- N is not side-effect free when the actual is global and modifiable
8752 -- indirectly from within a subprogram, because it may be passed by
8753 -- reference. The front-end must be conservative here and assume that
8754 -- this may happen with any array or record type. On the other hand, we
8755 -- cannot create temporaries for all expressions for which this
8756 -- condition is true, for various reasons that might require clearing up
8757 -- ??? For example, discriminant references that appear out of place, or
8758 -- spurious type errors with class-wide expressions. As a result, we
8759 -- limit the transformation to loop bounds, which is so far the only
8760 -- case that requires it.
8762 -----------------------------
8763 -- Safe_Prefixed_Reference --
8764 -----------------------------
8766 function Safe_Prefixed_Reference
(N
: Node_Id
) return Boolean is
8768 -- If prefix is not side effect free, definitely not safe
8770 if not Side_Effect_Free
(Prefix
(N
), Name_Req
, Variable_Ref
) then
8773 -- If the prefix is of an access type that is not access-to-constant,
8774 -- then this construct is a variable reference, which means it is to
8775 -- be considered to have side effects if Variable_Ref is set True.
8777 elsif Is_Access_Type
(Etype
(Prefix
(N
)))
8778 and then not Is_Access_Constant
(Etype
(Prefix
(N
)))
8779 and then Variable_Ref
8781 -- Exception is a prefix that is the result of a previous removal
8784 return Is_Entity_Name
(Prefix
(N
))
8785 and then not Comes_From_Source
(Prefix
(N
))
8786 and then Ekind
(Entity
(Prefix
(N
))) = E_Constant
8787 and then Is_Internal_Name
(Chars
(Entity
(Prefix
(N
))));
8789 -- If the prefix is an explicit dereference then this construct is a
8790 -- variable reference, which means it is to be considered to have
8791 -- side effects if Variable_Ref is True.
8793 -- We do NOT exclude dereferences of access-to-constant types because
8794 -- we handle them as constant view of variables.
8796 elsif Nkind
(Prefix
(N
)) = N_Explicit_Dereference
8797 and then Variable_Ref
8801 -- Note: The following test is the simplest way of solving a complex
8802 -- problem uncovered by the following test (Side effect on loop bound
8803 -- that is a subcomponent of a global variable:
8805 -- with Text_Io; use Text_Io;
8806 -- procedure Tloop is
8809 -- V : Natural := 4;
8810 -- S : String (1..5) := (others => 'a');
8817 -- with procedure Action;
8818 -- procedure Loop_G (Arg : X; Msg : String)
8820 -- procedure Loop_G (Arg : X; Msg : String) is
8822 -- Put_Line ("begin loop_g " & Msg & " will loop till: "
8823 -- & Natural'Image (Arg.V));
8824 -- for Index in 1 .. Arg.V loop
8826 -- (Natural'Image (Index) & " " & Arg.S (Index));
8827 -- if Index > 2 then
8831 -- Put_Line ("end loop_g " & Msg);
8834 -- procedure Loop1 is new Loop_G (Modi);
8835 -- procedure Modi is
8838 -- Loop1 (X1, "from modi");
8842 -- Loop1 (X1, "initial");
8845 -- The output of the above program should be:
8847 -- begin loop_g initial will loop till: 4
8851 -- begin loop_g from modi will loop till: 1
8853 -- end loop_g from modi
8855 -- begin loop_g from modi will loop till: 1
8857 -- end loop_g from modi
8858 -- end loop_g initial
8860 -- If a loop bound is a subcomponent of a global variable, a
8861 -- modification of that variable within the loop may incorrectly
8862 -- affect the execution of the loop.
8864 elsif Nkind
(Parent
(Parent
(N
))) = N_Loop_Parameter_Specification
8865 and then Within_In_Parameter
(Prefix
(N
))
8866 and then Variable_Ref
8870 -- All other cases are side effect free
8875 end Safe_Prefixed_Reference
;
8877 -------------------------
8878 -- Within_In_Parameter --
8879 -------------------------
8881 function Within_In_Parameter
(N
: Node_Id
) return Boolean is
8883 if not Comes_From_Source
(N
) then
8886 elsif Is_Entity_Name
(N
) then
8887 return Ekind
(Entity
(N
)) = E_In_Parameter
;
8889 elsif Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
8890 return Within_In_Parameter
(Prefix
(N
));
8895 end Within_In_Parameter
;
8897 -- Start of processing for Side_Effect_Free
8900 -- If volatile reference, always consider it to have side effects
8902 if Is_Volatile_Reference
(N
) then
8906 -- Note on checks that could raise Constraint_Error. Strictly, if we
8907 -- take advantage of 11.6, these checks do not count as side effects.
8908 -- However, we would prefer to consider that they are side effects,
8909 -- since the backend CSE does not work very well on expressions which
8910 -- can raise Constraint_Error. On the other hand if we don't consider
8911 -- them to be side effect free, then we get some awkward expansions
8912 -- in -gnato mode, resulting in code insertions at a point where we
8913 -- do not have a clear model for performing the insertions.
8915 -- Special handling for entity names
8917 if Is_Entity_Name
(N
) then
8919 -- A type reference is always side effect free
8921 if Is_Type
(Entity
(N
)) then
8924 -- Variables are considered to be a side effect if Variable_Ref
8925 -- is set or if we have a volatile reference and Name_Req is off.
8926 -- If Name_Req is True then we can't help returning a name which
8927 -- effectively allows multiple references in any case.
8929 elsif Is_Variable
(N
, Use_Original_Node
=> False) then
8930 return not Variable_Ref
8931 and then (not Is_Volatile_Reference
(N
) or else Name_Req
);
8933 -- Any other entity (e.g. a subtype name) is definitely side
8940 -- A value known at compile time is always side effect free
8942 elsif Compile_Time_Known_Value
(N
) then
8945 -- A variable renaming is not side-effect free, because the renaming
8946 -- will function like a macro in the front-end in some cases, and an
8947 -- assignment can modify the component designated by N, so we need to
8948 -- create a temporary for it.
8950 -- The guard testing for Entity being present is needed at least in
8951 -- the case of rewritten predicate expressions, and may well also be
8952 -- appropriate elsewhere. Obviously we can't go testing the entity
8953 -- field if it does not exist, so it's reasonable to say that this is
8954 -- not the renaming case if it does not exist.
8956 elsif Is_Entity_Name
(Original_Node
(N
))
8957 and then Present
(Entity
(Original_Node
(N
)))
8958 and then Is_Renaming_Of_Object
(Entity
(Original_Node
(N
)))
8959 and then Ekind
(Entity
(Original_Node
(N
))) /= E_Constant
8962 RO
: constant Node_Id
:=
8963 Renamed_Object
(Entity
(Original_Node
(N
)));
8966 -- If the renamed object is an indexed component, or an
8967 -- explicit dereference, then the designated object could
8968 -- be modified by an assignment.
8970 if Nkind_In
(RO
, N_Indexed_Component
,
8971 N_Explicit_Dereference
)
8975 -- A selected component must have a safe prefix
8977 elsif Nkind
(RO
) = N_Selected_Component
then
8978 return Safe_Prefixed_Reference
(RO
);
8980 -- In all other cases, designated object cannot be changed so
8981 -- we are side effect free.
8988 -- Remove_Side_Effects generates an object renaming declaration to
8989 -- capture the expression of a class-wide expression. In VM targets
8990 -- the frontend performs no expansion for dispatching calls to
8991 -- class- wide types since they are handled by the VM. Hence, we must
8992 -- locate here if this node corresponds to a previous invocation of
8993 -- Remove_Side_Effects to avoid a never ending loop in the frontend.
8995 elsif not Tagged_Type_Expansion
8996 and then not Comes_From_Source
(N
)
8997 and then Nkind
(Parent
(N
)) = N_Object_Renaming_Declaration
8998 and then Is_Class_Wide_Type
(Typ
)
9003 -- For other than entity names and compile time known values,
9004 -- check the node kind for special processing.
9008 -- An attribute reference is side effect free if its expressions
9009 -- are side effect free and its prefix is side effect free or
9010 -- is an entity reference.
9012 -- Is this right? what about x'first where x is a variable???
9014 when N_Attribute_Reference
=>
9015 return Side_Effect_Free
(Expressions
(N
), Name_Req
, Variable_Ref
)
9016 and then Attribute_Name
(N
) /= Name_Input
9017 and then (Is_Entity_Name
(Prefix
(N
))
9018 or else Side_Effect_Free
9019 (Prefix
(N
), Name_Req
, Variable_Ref
));
9021 -- A binary operator is side effect free if and both operands are
9022 -- side effect free. For this purpose binary operators include
9023 -- membership tests and short circuit forms.
9025 when N_Binary_Op | N_Membership_Test | N_Short_Circuit
=>
9026 return Side_Effect_Free
(Left_Opnd
(N
), Name_Req
, Variable_Ref
)
9028 Side_Effect_Free
(Right_Opnd
(N
), Name_Req
, Variable_Ref
);
9030 -- An explicit dereference is side effect free only if it is
9031 -- a side effect free prefixed reference.
9033 when N_Explicit_Dereference
=>
9034 return Safe_Prefixed_Reference
(N
);
9036 -- An expression with action is side effect free if its expression
9037 -- is side effect free and it has no actions.
9039 when N_Expression_With_Actions
=>
9040 return Is_Empty_List
(Actions
(N
))
9042 Side_Effect_Free
(Expression
(N
), Name_Req
, Variable_Ref
);
9044 -- A call to _rep_to_pos is side effect free, since we generate
9045 -- this pure function call ourselves. Moreover it is critically
9046 -- important to make this exception, since otherwise we can have
9047 -- discriminants in array components which don't look side effect
9048 -- free in the case of an array whose index type is an enumeration
9049 -- type with an enumeration rep clause.
9051 -- All other function calls are not side effect free
9053 when N_Function_Call
=>
9054 return Nkind
(Name
(N
)) = N_Identifier
9055 and then Is_TSS
(Name
(N
), TSS_Rep_To_Pos
)
9058 (First
(Parameter_Associations
(N
)), Name_Req
, Variable_Ref
);
9060 -- An IF expression is side effect free if it's of a scalar type, and
9061 -- all its components are all side effect free (conditions and then
9062 -- actions and else actions). We restrict to scalar types, since it
9063 -- is annoying to deal with things like (if A then B else C)'First
9064 -- where the type involved is a string type.
9066 when N_If_Expression
=>
9067 return Is_Scalar_Type
(Typ
)
9069 Side_Effect_Free
(Expressions
(N
), Name_Req
, Variable_Ref
);
9071 -- An indexed component is side effect free if it is a side
9072 -- effect free prefixed reference and all the indexing
9073 -- expressions are side effect free.
9075 when N_Indexed_Component
=>
9076 return Side_Effect_Free
(Expressions
(N
), Name_Req
, Variable_Ref
)
9077 and then Safe_Prefixed_Reference
(N
);
9079 -- A type qualification is side effect free if the expression
9080 -- is side effect free.
9082 when N_Qualified_Expression
=>
9083 return Side_Effect_Free
(Expression
(N
), Name_Req
, Variable_Ref
);
9085 -- A selected component is side effect free only if it is a side
9086 -- effect free prefixed reference.
9088 when N_Selected_Component
=>
9089 return Safe_Prefixed_Reference
(N
);
9091 -- A range is side effect free if the bounds are side effect free
9094 return Side_Effect_Free
(Low_Bound
(N
), Name_Req
, Variable_Ref
)
9096 Side_Effect_Free
(High_Bound
(N
), Name_Req
, Variable_Ref
);
9098 -- A slice is side effect free if it is a side effect free
9099 -- prefixed reference and the bounds are side effect free.
9102 return Side_Effect_Free
9103 (Discrete_Range
(N
), Name_Req
, Variable_Ref
)
9104 and then Safe_Prefixed_Reference
(N
);
9106 -- A type conversion is side effect free if the expression to be
9107 -- converted is side effect free.
9109 when N_Type_Conversion
=>
9110 return Side_Effect_Free
(Expression
(N
), Name_Req
, Variable_Ref
);
9112 -- A unary operator is side effect free if the operand
9113 -- is side effect free.
9116 return Side_Effect_Free
(Right_Opnd
(N
), Name_Req
, Variable_Ref
);
9118 -- An unchecked type conversion is side effect free only if it
9119 -- is safe and its argument is side effect free.
9121 when N_Unchecked_Type_Conversion
=>
9122 return Safe_Unchecked_Type_Conversion
(N
)
9124 Side_Effect_Free
(Expression
(N
), Name_Req
, Variable_Ref
);
9126 -- An unchecked expression is side effect free if its expression
9127 -- is side effect free.
9129 when N_Unchecked_Expression
=>
9130 return Side_Effect_Free
(Expression
(N
), Name_Req
, Variable_Ref
);
9132 -- A literal is side effect free
9134 when N_Character_Literal |
9140 -- We consider that anything else has side effects. This is a bit
9141 -- crude, but we are pretty close for most common cases, and we
9142 -- are certainly correct (i.e. we never return True when the
9143 -- answer should be False).
9148 end Side_Effect_Free
;
9150 -- A list is side effect free if all elements of the list are side
9153 function Side_Effect_Free
9155 Name_Req
: Boolean := False;
9156 Variable_Ref
: Boolean := False) return Boolean
9161 if L
= No_List
or else L
= Error_List
then
9166 while Present
(N
) loop
9167 if not Side_Effect_Free
(N
, Name_Req
, Variable_Ref
) then
9176 end Side_Effect_Free
;
9178 ----------------------------------
9179 -- Silly_Boolean_Array_Not_Test --
9180 ----------------------------------
9182 -- This procedure implements an odd and silly test. We explicitly check
9183 -- for the case where the 'First of the component type is equal to the
9184 -- 'Last of this component type, and if this is the case, we make sure
9185 -- that constraint error is raised. The reason is that the NOT is bound
9186 -- to cause CE in this case, and we will not otherwise catch it.
9188 -- No such check is required for AND and OR, since for both these cases
9189 -- False op False = False, and True op True = True. For the XOR case,
9190 -- see Silly_Boolean_Array_Xor_Test.
9192 -- Believe it or not, this was reported as a bug. Note that nearly always,
9193 -- the test will evaluate statically to False, so the code will be
9194 -- statically removed, and no extra overhead caused.
9196 procedure Silly_Boolean_Array_Not_Test
(N
: Node_Id
; T
: Entity_Id
) is
9197 Loc
: constant Source_Ptr
:= Sloc
(N
);
9198 CT
: constant Entity_Id
:= Component_Type
(T
);
9201 -- The check we install is
9203 -- constraint_error when
9204 -- component_type'first = component_type'last
9205 -- and then array_type'Length /= 0)
9207 -- We need the last guard because we don't want to raise CE for empty
9208 -- arrays since no out of range values result. (Empty arrays with a
9209 -- component type of True .. True -- very useful -- even the ACATS
9210 -- does not test that marginal case).
9213 Make_Raise_Constraint_Error
(Loc
,
9219 Make_Attribute_Reference
(Loc
,
9220 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
9221 Attribute_Name
=> Name_First
),
9224 Make_Attribute_Reference
(Loc
,
9225 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
9226 Attribute_Name
=> Name_Last
)),
9228 Right_Opnd
=> Make_Non_Empty_Check
(Loc
, Right_Opnd
(N
))),
9229 Reason
=> CE_Range_Check_Failed
));
9230 end Silly_Boolean_Array_Not_Test
;
9232 ----------------------------------
9233 -- Silly_Boolean_Array_Xor_Test --
9234 ----------------------------------
9236 -- This procedure implements an odd and silly test. We explicitly check
9237 -- for the XOR case where the component type is True .. True, since this
9238 -- will raise constraint error. A special check is required since CE
9239 -- will not be generated otherwise (cf Expand_Packed_Not).
9241 -- No such check is required for AND and OR, since for both these cases
9242 -- False op False = False, and True op True = True, and no check is
9243 -- required for the case of False .. False, since False xor False = False.
9244 -- See also Silly_Boolean_Array_Not_Test
9246 procedure Silly_Boolean_Array_Xor_Test
(N
: Node_Id
; T
: Entity_Id
) is
9247 Loc
: constant Source_Ptr
:= Sloc
(N
);
9248 CT
: constant Entity_Id
:= Component_Type
(T
);
9251 -- The check we install is
9253 -- constraint_error when
9254 -- Boolean (component_type'First)
9255 -- and then Boolean (component_type'Last)
9256 -- and then array_type'Length /= 0)
9258 -- We need the last guard because we don't want to raise CE for empty
9259 -- arrays since no out of range values result (Empty arrays with a
9260 -- component type of True .. True -- very useful -- even the ACATS
9261 -- does not test that marginal case).
9264 Make_Raise_Constraint_Error
(Loc
,
9270 Convert_To
(Standard_Boolean
,
9271 Make_Attribute_Reference
(Loc
,
9272 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
9273 Attribute_Name
=> Name_First
)),
9276 Convert_To
(Standard_Boolean
,
9277 Make_Attribute_Reference
(Loc
,
9278 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
9279 Attribute_Name
=> Name_Last
))),
9281 Right_Opnd
=> Make_Non_Empty_Check
(Loc
, Right_Opnd
(N
))),
9282 Reason
=> CE_Range_Check_Failed
));
9283 end Silly_Boolean_Array_Xor_Test
;
9285 --------------------------
9286 -- Target_Has_Fixed_Ops --
9287 --------------------------
9289 Integer_Sized_Small
: Ureal
;
9290 -- Set to 2.0 ** -(Integer'Size - 1) the first time that this function is
9291 -- called (we don't want to compute it more than once).
9293 Long_Integer_Sized_Small
: Ureal
;
9294 -- Set to 2.0 ** -(Long_Integer'Size - 1) the first time that this function
9295 -- is called (we don't want to compute it more than once)
9297 First_Time_For_THFO
: Boolean := True;
9298 -- Set to False after first call (if Fractional_Fixed_Ops_On_Target)
9300 function Target_Has_Fixed_Ops
9301 (Left_Typ
: Entity_Id
;
9302 Right_Typ
: Entity_Id
;
9303 Result_Typ
: Entity_Id
) return Boolean
9305 function Is_Fractional_Type
(Typ
: Entity_Id
) return Boolean;
9306 -- Return True if the given type is a fixed-point type with a small
9307 -- value equal to 2 ** (-(T'Object_Size - 1)) and whose values have
9308 -- an absolute value less than 1.0. This is currently limited to
9309 -- fixed-point types that map to Integer or Long_Integer.
9311 ------------------------
9312 -- Is_Fractional_Type --
9313 ------------------------
9315 function Is_Fractional_Type
(Typ
: Entity_Id
) return Boolean is
9317 if Esize
(Typ
) = Standard_Integer_Size
then
9318 return Small_Value
(Typ
) = Integer_Sized_Small
;
9320 elsif Esize
(Typ
) = Standard_Long_Integer_Size
then
9321 return Small_Value
(Typ
) = Long_Integer_Sized_Small
;
9326 end Is_Fractional_Type
;
9328 -- Start of processing for Target_Has_Fixed_Ops
9331 -- Return False if Fractional_Fixed_Ops_On_Target is false
9333 if not Fractional_Fixed_Ops_On_Target
then
9337 -- Here the target has Fractional_Fixed_Ops, if first time, compute
9338 -- standard constants used by Is_Fractional_Type.
9340 if First_Time_For_THFO
then
9341 First_Time_For_THFO
:= False;
9343 Integer_Sized_Small
:=
9346 Den
=> UI_From_Int
(Standard_Integer_Size
- 1),
9349 Long_Integer_Sized_Small
:=
9352 Den
=> UI_From_Int
(Standard_Long_Integer_Size
- 1),
9356 -- Return True if target supports fixed-by-fixed multiply/divide for
9357 -- fractional fixed-point types (see Is_Fractional_Type) and the operand
9358 -- and result types are equivalent fractional types.
9360 return Is_Fractional_Type
(Base_Type
(Left_Typ
))
9361 and then Is_Fractional_Type
(Base_Type
(Right_Typ
))
9362 and then Is_Fractional_Type
(Base_Type
(Result_Typ
))
9363 and then Esize
(Left_Typ
) = Esize
(Right_Typ
)
9364 and then Esize
(Left_Typ
) = Esize
(Result_Typ
);
9365 end Target_Has_Fixed_Ops
;
9367 ------------------------------------------
9368 -- Type_May_Have_Bit_Aligned_Components --
9369 ------------------------------------------
9371 function Type_May_Have_Bit_Aligned_Components
9372 (Typ
: Entity_Id
) return Boolean
9375 -- Array type, check component type
9377 if Is_Array_Type
(Typ
) then
9379 Type_May_Have_Bit_Aligned_Components
(Component_Type
(Typ
));
9381 -- Record type, check components
9383 elsif Is_Record_Type
(Typ
) then
9388 E
:= First_Component_Or_Discriminant
(Typ
);
9389 while Present
(E
) loop
9390 if Component_May_Be_Bit_Aligned
(E
)
9391 or else Type_May_Have_Bit_Aligned_Components
(Etype
(E
))
9396 Next_Component_Or_Discriminant
(E
);
9402 -- Type other than array or record is always OK
9407 end Type_May_Have_Bit_Aligned_Components
;
9409 ----------------------------------
9410 -- Within_Case_Or_If_Expression --
9411 ----------------------------------
9413 function Within_Case_Or_If_Expression
(N
: Node_Id
) return Boolean is
9417 -- Locate an enclosing case or if expression. Note that these constructs
9418 -- can be expanded into Expression_With_Actions, hence the test of the
9422 while Present
(Par
) loop
9423 if Nkind_In
(Original_Node
(Par
), N_Case_Expression
,
9428 -- Prevent the search from going too far
9430 elsif Is_Body_Or_Package_Declaration
(Par
) then
9434 Par
:= Parent
(Par
);
9438 end Within_Case_Or_If_Expression
;
9440 --------------------------------
9441 -- Within_Internal_Subprogram --
9442 --------------------------------
9444 function Within_Internal_Subprogram
return Boolean is
9449 while Present
(S
) and then not Is_Subprogram
(S
) loop
9454 and then Get_TSS_Name
(S
) /= TSS_Null
9455 and then not Is_Predicate_Function
(S
)
9456 and then not Is_Predicate_Function_M
(S
);
9457 end Within_Internal_Subprogram
;