1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2013, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with 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 Inline
; use Inline
;
38 with Itypes
; use Itypes
;
40 with Nlists
; use Nlists
;
41 with Nmake
; use Nmake
;
43 with Restrict
; use Restrict
;
44 with Rident
; use Rident
;
46 with Sem_Aux
; use Sem_Aux
;
47 with Sem_Ch8
; use Sem_Ch8
;
48 with Sem_Eval
; use Sem_Eval
;
49 with Sem_Res
; use Sem_Res
;
50 with Sem_Type
; use Sem_Type
;
51 with Sem_Util
; use Sem_Util
;
52 with Snames
; use Snames
;
53 with Stand
; use Stand
;
54 with Stringt
; use Stringt
;
55 with Targparm
; use Targparm
;
56 with Tbuild
; use Tbuild
;
57 with Ttypes
; use Ttypes
;
58 with Urealp
; use Urealp
;
59 with Validsw
; use Validsw
;
61 package body Exp_Util
is
63 -----------------------
64 -- Local Subprograms --
65 -----------------------
67 function Build_Task_Array_Image
71 Dyn
: Boolean := False) return Node_Id
;
72 -- Build function to generate the image string for a task that is an array
73 -- component, concatenating the images of each index. To avoid storage
74 -- leaks, the string is built with successive slice assignments. The flag
75 -- Dyn indicates whether this is called for the initialization procedure of
76 -- an array of tasks, or for the name of a dynamically created task that is
77 -- assigned to an indexed component.
79 function Build_Task_Image_Function
83 Res
: Entity_Id
) return Node_Id
;
84 -- Common processing for Task_Array_Image and Task_Record_Image. Build
85 -- function body that computes image.
87 procedure Build_Task_Image_Prefix
96 -- Common processing for Task_Array_Image and Task_Record_Image. Create
97 -- local variables and assign prefix of name to result string.
99 function Build_Task_Record_Image
102 Dyn
: Boolean := False) return Node_Id
;
103 -- Build function to generate the image string for a task that is a record
104 -- component. Concatenate name of variable with that of selector. The flag
105 -- Dyn indicates whether this is called for the initialization procedure of
106 -- record with task components, or for a dynamically created task that is
107 -- assigned to a selected component.
109 function Make_CW_Equivalent_Type
111 E
: Node_Id
) return Entity_Id
;
112 -- T is a class-wide type entity, E is the initial expression node that
113 -- constrains T in case such as: " X: T := E" or "new T'(E)". This function
114 -- returns the entity of the Equivalent type and inserts on the fly the
115 -- necessary declaration such as:
117 -- type anon is record
118 -- _parent : Root_Type (T); constrained with E discriminants (if any)
119 -- Extension : String (1 .. expr to match size of E);
122 -- This record is compatible with any object of the class of T thanks to
123 -- the first field and has the same size as E thanks to the second.
125 function Make_Literal_Range
127 Literal_Typ
: Entity_Id
) return Node_Id
;
128 -- Produce a Range node whose bounds are:
129 -- Low_Bound (Literal_Type) ..
130 -- Low_Bound (Literal_Type) + (Length (Literal_Typ) - 1)
131 -- this is used for expanding declarations like X : String := "sdfgdfg";
133 -- If the index type of the target array is not integer, we generate:
134 -- Low_Bound (Literal_Type) ..
136 -- (Literal_Type'Pos (Low_Bound (Literal_Type))
137 -- + (Length (Literal_Typ) -1))
139 function Make_Non_Empty_Check
141 N
: Node_Id
) return Node_Id
;
142 -- Produce a boolean expression checking that the unidimensional array
143 -- node N is not empty.
145 function New_Class_Wide_Subtype
147 N
: Node_Id
) return Entity_Id
;
148 -- Create an implicit subtype of CW_Typ attached to node N
150 function Requires_Cleanup_Actions
153 Nested_Constructs
: Boolean) return Boolean;
154 -- Given a list L, determine whether it contains one of the following:
156 -- 1) controlled objects
157 -- 2) library-level tagged types
159 -- Lib_Level is True when the list comes from a construct at the library
160 -- level, and False otherwise. Nested_Constructs is True when any nested
161 -- packages declared in L must be processed, and False otherwise.
163 -------------------------------------
164 -- Activate_Atomic_Synchronization --
165 -------------------------------------
167 procedure Activate_Atomic_Synchronization
(N
: Node_Id
) is
171 case Nkind
(Parent
(N
)) is
173 -- Check for cases of appearing in the prefix of a construct where
174 -- we don't need atomic synchronization for this kind of usage.
177 -- Nothing to do if we are the prefix of an attribute, since we
178 -- do not want an atomic sync operation for things like 'Size.
180 N_Attribute_Reference |
182 -- The N_Reference node is like an attribute
186 -- Nothing to do for a reference to a component (or components)
187 -- of a composite object. Only reads and updates of the object
188 -- as a whole require atomic synchronization (RM C.6 (15)).
190 N_Indexed_Component |
191 N_Selected_Component |
194 -- For all the above cases, nothing to do if we are the prefix
196 if Prefix
(Parent
(N
)) = N
then
203 -- Go ahead and set the flag
205 Set_Atomic_Sync_Required
(N
);
207 -- Generate info message if requested
209 if Warn_On_Atomic_Synchronization
then
214 when N_Selected_Component | N_Expanded_Name
=>
215 Msg_Node
:= Selector_Name
(N
);
217 when N_Explicit_Dereference | N_Indexed_Component
=>
221 pragma Assert
(False);
225 if Present
(Msg_Node
) then
227 ("?N?info: atomic synchronization set for &", Msg_Node
);
230 ("?N?info: atomic synchronization set", N
);
233 end Activate_Atomic_Synchronization
;
235 ----------------------
236 -- Adjust_Condition --
237 ----------------------
239 procedure Adjust_Condition
(N
: Node_Id
) is
246 Loc
: constant Source_Ptr
:= Sloc
(N
);
247 T
: constant Entity_Id
:= Etype
(N
);
251 -- Defend against a call where the argument has no type, or has a
252 -- type that is not Boolean. This can occur because of prior errors.
254 if No
(T
) or else not Is_Boolean_Type
(T
) then
258 -- Apply validity checking if needed
260 if Validity_Checks_On
and Validity_Check_Tests
then
264 -- Immediate return if standard boolean, the most common case,
265 -- where nothing needs to be done.
267 if Base_Type
(T
) = Standard_Boolean
then
271 -- Case of zero/non-zero semantics or non-standard enumeration
272 -- representation. In each case, we rewrite the node as:
274 -- ityp!(N) /= False'Enum_Rep
276 -- where ityp is an integer type with large enough size to hold any
279 if Nonzero_Is_True
(T
) or else Has_Non_Standard_Rep
(T
) then
280 if Esize
(T
) <= Esize
(Standard_Integer
) then
281 Ti
:= Standard_Integer
;
283 Ti
:= Standard_Long_Long_Integer
;
288 Left_Opnd
=> Unchecked_Convert_To
(Ti
, N
),
290 Make_Attribute_Reference
(Loc
,
291 Attribute_Name
=> Name_Enum_Rep
,
293 New_Occurrence_Of
(First_Literal
(T
), Loc
))));
294 Analyze_And_Resolve
(N
, Standard_Boolean
);
297 Rewrite
(N
, Convert_To
(Standard_Boolean
, N
));
298 Analyze_And_Resolve
(N
, Standard_Boolean
);
301 end Adjust_Condition
;
303 ------------------------
304 -- Adjust_Result_Type --
305 ------------------------
307 procedure Adjust_Result_Type
(N
: Node_Id
; T
: Entity_Id
) is
309 -- Ignore call if current type is not Standard.Boolean
311 if Etype
(N
) /= Standard_Boolean
then
315 -- If result is already of correct type, nothing to do. Note that
316 -- this will get the most common case where everything has a type
317 -- of Standard.Boolean.
319 if Base_Type
(T
) = Standard_Boolean
then
324 KP
: constant Node_Kind
:= Nkind
(Parent
(N
));
327 -- If result is to be used as a Condition in the syntax, no need
328 -- to convert it back, since if it was changed to Standard.Boolean
329 -- using Adjust_Condition, that is just fine for this usage.
331 if KP
in N_Raise_xxx_Error
or else KP
in N_Has_Condition
then
334 -- If result is an operand of another logical operation, no need
335 -- to reset its type, since Standard.Boolean is just fine, and
336 -- such operations always do Adjust_Condition on their operands.
338 elsif KP
in N_Op_Boolean
339 or else KP
in N_Short_Circuit
340 or else KP
= N_Op_Not
344 -- Otherwise we perform a conversion from the current type, which
345 -- must be Standard.Boolean, to the desired type.
349 Rewrite
(N
, Convert_To
(T
, N
));
350 Analyze_And_Resolve
(N
, T
);
354 end Adjust_Result_Type
;
356 --------------------------
357 -- Append_Freeze_Action --
358 --------------------------
360 procedure Append_Freeze_Action
(T
: Entity_Id
; N
: Node_Id
) is
364 Ensure_Freeze_Node
(T
);
365 Fnode
:= Freeze_Node
(T
);
367 if No
(Actions
(Fnode
)) then
368 Set_Actions
(Fnode
, New_List
(N
));
370 Append
(N
, Actions
(Fnode
));
373 end Append_Freeze_Action
;
375 ---------------------------
376 -- Append_Freeze_Actions --
377 ---------------------------
379 procedure Append_Freeze_Actions
(T
: Entity_Id
; L
: List_Id
) is
387 Ensure_Freeze_Node
(T
);
388 Fnode
:= Freeze_Node
(T
);
390 if No
(Actions
(Fnode
)) then
391 Set_Actions
(Fnode
, L
);
393 Append_List
(L
, Actions
(Fnode
));
395 end Append_Freeze_Actions
;
397 ------------------------------------
398 -- Build_Allocate_Deallocate_Proc --
399 ------------------------------------
401 procedure Build_Allocate_Deallocate_Proc
403 Is_Allocate
: Boolean)
405 Desig_Typ
: Entity_Id
;
408 Proc_To_Call
: Node_Id
:= Empty
;
411 function Find_Finalize_Address
(Typ
: Entity_Id
) return Entity_Id
;
412 -- Locate TSS primitive Finalize_Address in type Typ
414 function Find_Object
(E
: Node_Id
) return Node_Id
;
415 -- Given an arbitrary expression of an allocator, try to find an object
416 -- reference in it, otherwise return the original expression.
418 function Is_Allocate_Deallocate_Proc
(Subp
: Entity_Id
) return Boolean;
419 -- Determine whether subprogram Subp denotes a custom allocate or
422 ---------------------------
423 -- Find_Finalize_Address --
424 ---------------------------
426 function Find_Finalize_Address
(Typ
: Entity_Id
) return Entity_Id
is
427 Utyp
: Entity_Id
:= Typ
;
430 -- Handle protected class-wide or task class-wide types
432 if Is_Class_Wide_Type
(Utyp
) then
433 if Is_Concurrent_Type
(Root_Type
(Utyp
)) then
434 Utyp
:= Root_Type
(Utyp
);
436 elsif Is_Private_Type
(Root_Type
(Utyp
))
437 and then Present
(Full_View
(Root_Type
(Utyp
)))
438 and then Is_Concurrent_Type
(Full_View
(Root_Type
(Utyp
)))
440 Utyp
:= Full_View
(Root_Type
(Utyp
));
444 -- Handle private types
446 if Is_Private_Type
(Utyp
) and then Present
(Full_View
(Utyp
)) then
447 Utyp
:= Full_View
(Utyp
);
450 -- Handle protected and task types
452 if Is_Concurrent_Type
(Utyp
)
453 and then Present
(Corresponding_Record_Type
(Utyp
))
455 Utyp
:= Corresponding_Record_Type
(Utyp
);
458 Utyp
:= Underlying_Type
(Base_Type
(Utyp
));
460 -- Deal with non-tagged derivation of private views. If the parent is
461 -- now known to be protected, the finalization routine is the one
462 -- defined on the corresponding record of the ancestor (corresponding
463 -- records do not automatically inherit operations, but maybe they
466 if Is_Untagged_Derivation
(Typ
) then
467 if Is_Protected_Type
(Typ
) then
468 Utyp
:= Corresponding_Record_Type
(Root_Type
(Base_Type
(Typ
)));
470 Utyp
:= Underlying_Type
(Root_Type
(Base_Type
(Typ
)));
472 if Is_Protected_Type
(Utyp
) then
473 Utyp
:= Corresponding_Record_Type
(Utyp
);
478 -- If the underlying_type is a subtype, we are dealing with the
479 -- completion of a private type. We need to access the base type and
480 -- generate a conversion to it.
482 if Utyp
/= Base_Type
(Utyp
) then
483 pragma Assert
(Is_Private_Type
(Typ
));
485 Utyp
:= Base_Type
(Utyp
);
488 -- When dealing with an internally built full view for a type with
489 -- unknown discriminants, use the original record type.
491 if Is_Underlying_Record_View
(Utyp
) then
492 Utyp
:= Etype
(Utyp
);
495 return TSS
(Utyp
, TSS_Finalize_Address
);
496 end Find_Finalize_Address
;
502 function Find_Object
(E
: Node_Id
) return Node_Id
is
506 pragma Assert
(Is_Allocate
);
510 if Nkind_In
(Expr
, N_Qualified_Expression
,
511 N_Unchecked_Type_Conversion
)
513 Expr
:= Expression
(Expr
);
515 elsif Nkind
(Expr
) = N_Explicit_Dereference
then
516 Expr
:= Prefix
(Expr
);
526 ---------------------------------
527 -- Is_Allocate_Deallocate_Proc --
528 ---------------------------------
530 function Is_Allocate_Deallocate_Proc
(Subp
: Entity_Id
) return Boolean is
532 -- Look for a subprogram body with only one statement which is a
533 -- call to Allocate_Any_Controlled / Deallocate_Any_Controlled.
535 if Ekind
(Subp
) = E_Procedure
536 and then Nkind
(Parent
(Parent
(Subp
))) = N_Subprogram_Body
539 HSS
: constant Node_Id
:=
540 Handled_Statement_Sequence
(Parent
(Parent
(Subp
)));
544 if Present
(Statements
(HSS
))
545 and then Nkind
(First
(Statements
(HSS
))) =
546 N_Procedure_Call_Statement
548 Proc
:= Entity
(Name
(First
(Statements
(HSS
))));
551 Is_RTE
(Proc
, RE_Allocate_Any_Controlled
)
552 or else Is_RTE
(Proc
, RE_Deallocate_Any_Controlled
);
558 end Is_Allocate_Deallocate_Proc
;
560 -- Start of processing for Build_Allocate_Deallocate_Proc
563 -- Do not perform this expansion in SPARK mode because it is not
570 -- Obtain the attributes of the allocation / deallocation
572 if Nkind
(N
) = N_Free_Statement
then
573 Expr
:= Expression
(N
);
574 Ptr_Typ
:= Base_Type
(Etype
(Expr
));
575 Proc_To_Call
:= Procedure_To_Call
(N
);
578 if Nkind
(N
) = N_Object_Declaration
then
579 Expr
:= Expression
(N
);
584 -- In certain cases an allocator with a qualified expression may
585 -- be relocated and used as the initialization expression of a
589 -- Obj : Ptr_Typ := new Desig_Typ'(...);
592 -- Tmp : Ptr_Typ := new Desig_Typ'(...);
593 -- Obj : Ptr_Typ := Tmp;
595 -- Since the allocator is always marked as analyzed to avoid infinite
596 -- expansion, it will never be processed by this routine given that
597 -- the designated type needs finalization actions. Detect this case
598 -- and complete the expansion of the allocator.
600 if Nkind
(Expr
) = N_Identifier
601 and then Nkind
(Parent
(Entity
(Expr
))) = N_Object_Declaration
602 and then Nkind
(Expression
(Parent
(Entity
(Expr
)))) = N_Allocator
604 Build_Allocate_Deallocate_Proc
(Parent
(Entity
(Expr
)), True);
608 -- The allocator may have been rewritten into something else in which
609 -- case the expansion performed by this routine does not apply.
611 if Nkind
(Expr
) /= N_Allocator
then
615 Ptr_Typ
:= Base_Type
(Etype
(Expr
));
616 Proc_To_Call
:= Procedure_To_Call
(Expr
);
619 Pool_Id
:= Associated_Storage_Pool
(Ptr_Typ
);
620 Desig_Typ
:= Available_View
(Designated_Type
(Ptr_Typ
));
622 -- Handle concurrent types
624 if Is_Concurrent_Type
(Desig_Typ
)
625 and then Present
(Corresponding_Record_Type
(Desig_Typ
))
627 Desig_Typ
:= Corresponding_Record_Type
(Desig_Typ
);
630 -- Do not process allocations / deallocations without a pool
635 -- Do not process allocations on / deallocations from the secondary
638 elsif Is_RTE
(Pool_Id
, RE_SS_Pool
) then
641 -- Do not replicate the machinery if the allocator / free has already
642 -- been expanded and has a custom Allocate / Deallocate.
644 elsif Present
(Proc_To_Call
)
645 and then Is_Allocate_Deallocate_Proc
(Proc_To_Call
)
650 if Needs_Finalization
(Desig_Typ
) then
652 -- Certain run-time configurations and targets do not provide support
653 -- for controlled types.
655 if Restriction_Active
(No_Finalization
) then
658 -- Do nothing if the access type may never allocate / deallocate
661 elsif No_Pool_Assigned
(Ptr_Typ
) then
664 -- Access-to-controlled types are not supported on .NET/JVM since
665 -- these targets cannot support pools and address arithmetic.
667 elsif VM_Target
/= No_VM
then
671 -- The allocation / deallocation of a controlled object must be
672 -- chained on / detached from a finalization master.
674 pragma Assert
(Present
(Finalization_Master
(Ptr_Typ
)));
676 -- The only other kind of allocation / deallocation supported by this
677 -- routine is on / from a subpool.
679 elsif Nkind
(Expr
) = N_Allocator
680 and then No
(Subpool_Handle_Name
(Expr
))
686 Loc
: constant Source_Ptr
:= Sloc
(N
);
687 Addr_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
688 Alig_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'L');
689 Proc_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'P');
690 Size_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'S');
693 Fin_Addr_Id
: Entity_Id
;
694 Fin_Mas_Act
: Node_Id
;
695 Fin_Mas_Id
: Entity_Id
;
696 Proc_To_Call
: Entity_Id
;
697 Subpool
: Node_Id
:= Empty
;
700 -- Step 1: Construct all the actuals for the call to library routine
701 -- Allocate_Any_Controlled / Deallocate_Any_Controlled.
705 Actuals
:= New_List
(New_Reference_To
(Pool_Id
, Loc
));
711 if Nkind
(Expr
) = N_Allocator
then
712 Subpool
:= Subpool_Handle_Name
(Expr
);
715 -- If a subpool is present it can be an arbitrary name, so make
716 -- the actual by copying the tree.
718 if Present
(Subpool
) then
719 Append_To
(Actuals
, New_Copy_Tree
(Subpool
, New_Sloc
=> Loc
));
721 Append_To
(Actuals
, Make_Null
(Loc
));
724 -- c) Finalization master
726 if Needs_Finalization
(Desig_Typ
) then
727 Fin_Mas_Id
:= Finalization_Master
(Ptr_Typ
);
728 Fin_Mas_Act
:= New_Reference_To
(Fin_Mas_Id
, Loc
);
730 -- Handle the case where the master is actually a pointer to a
731 -- master. This case arises in build-in-place functions.
733 if Is_Access_Type
(Etype
(Fin_Mas_Id
)) then
734 Append_To
(Actuals
, Fin_Mas_Act
);
737 Make_Attribute_Reference
(Loc
,
738 Prefix
=> Fin_Mas_Act
,
739 Attribute_Name
=> Name_Unrestricted_Access
));
742 Append_To
(Actuals
, Make_Null
(Loc
));
745 -- d) Finalize_Address
747 -- Primitive Finalize_Address is never generated in CodePeer mode
748 -- since it contains an Unchecked_Conversion.
750 if Needs_Finalization
(Desig_Typ
) and then not CodePeer_Mode
then
751 Fin_Addr_Id
:= Find_Finalize_Address
(Desig_Typ
);
752 pragma Assert
(Present
(Fin_Addr_Id
));
755 Make_Attribute_Reference
(Loc
,
756 Prefix
=> New_Reference_To
(Fin_Addr_Id
, Loc
),
757 Attribute_Name
=> Name_Unrestricted_Access
));
759 Append_To
(Actuals
, Make_Null
(Loc
));
767 Append_To
(Actuals
, New_Reference_To
(Addr_Id
, Loc
));
768 Append_To
(Actuals
, New_Reference_To
(Size_Id
, Loc
));
770 if Is_Allocate
or else not Is_Class_Wide_Type
(Desig_Typ
) then
771 Append_To
(Actuals
, New_Reference_To
(Alig_Id
, Loc
));
773 -- For deallocation of class wide types we obtain the value of
774 -- alignment from the Type Specific Record of the deallocated object.
775 -- This is needed because the frontend expansion of class-wide types
776 -- into equivalent types confuses the backend.
782 -- ... because 'Alignment applied to class-wide types is expanded
783 -- into the code that reads the value of alignment from the TSD
784 -- (see Expand_N_Attribute_Reference)
787 Unchecked_Convert_To
(RTE
(RE_Storage_Offset
),
788 Make_Attribute_Reference
(Loc
,
790 Make_Explicit_Dereference
(Loc
, Relocate_Node
(Expr
)),
791 Attribute_Name
=> Name_Alignment
)));
796 -- Generate a run-time check to determine whether a class-wide object
797 -- is truly controlled.
799 if Needs_Finalization
(Desig_Typ
) then
800 if Is_Class_Wide_Type
(Desig_Typ
)
801 or else Is_Generic_Actual_Type
(Desig_Typ
)
804 Flag_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'F');
811 Temp
:= Find_Object
(Expression
(Expr
));
816 -- Processing for generic actuals
818 if Is_Generic_Actual_Type
(Desig_Typ
) then
820 New_Reference_To
(Boolean_Literals
821 (Needs_Finalization
(Base_Type
(Desig_Typ
))), Loc
);
823 -- Processing for subtype indications
825 elsif Nkind
(Temp
) in N_Has_Entity
826 and then Is_Type
(Entity
(Temp
))
829 New_Reference_To
(Boolean_Literals
830 (Needs_Finalization
(Entity
(Temp
))), Loc
);
832 -- Generate a runtime check to test the controlled state of
833 -- an object for the purposes of allocation / deallocation.
836 -- The following case arises when allocating through an
837 -- interface class-wide type, generate:
841 if Is_RTE
(Etype
(Temp
), RE_Tag_Ptr
) then
843 Make_Explicit_Dereference
(Loc
,
845 Relocate_Node
(Temp
));
852 Make_Attribute_Reference
(Loc
,
854 Relocate_Node
(Temp
),
855 Attribute_Name
=> Name_Tag
);
859 -- Needs_Finalization (<Param>)
862 Make_Function_Call
(Loc
,
864 New_Reference_To
(RTE
(RE_Needs_Finalization
), Loc
),
865 Parameter_Associations
=> New_List
(Param
));
868 -- Create the temporary which represents the finalization
869 -- state of the expression. Generate:
871 -- F : constant Boolean := <Flag_Expr>;
874 Make_Object_Declaration
(Loc
,
875 Defining_Identifier
=> Flag_Id
,
876 Constant_Present
=> True,
878 New_Reference_To
(Standard_Boolean
, Loc
),
879 Expression
=> Flag_Expr
));
881 -- The flag acts as the last actual
883 Append_To
(Actuals
, New_Reference_To
(Flag_Id
, Loc
));
886 -- The object is statically known to be controlled
889 Append_To
(Actuals
, New_Reference_To
(Standard_True
, Loc
));
893 Append_To
(Actuals
, New_Reference_To
(Standard_False
, Loc
));
900 New_Reference_To
(Boolean_Literals
(Present
(Subpool
)), Loc
));
903 -- Step 2: Build a wrapper Allocate / Deallocate which internally
904 -- calls Allocate_Any_Controlled / Deallocate_Any_Controlled.
906 -- Select the proper routine to call
909 Proc_To_Call
:= RTE
(RE_Allocate_Any_Controlled
);
911 Proc_To_Call
:= RTE
(RE_Deallocate_Any_Controlled
);
914 -- Create a custom Allocate / Deallocate routine which has identical
915 -- profile to that of System.Storage_Pools.
918 Make_Subprogram_Body
(Loc
,
923 Make_Procedure_Specification
(Loc
,
924 Defining_Unit_Name
=> Proc_Id
,
925 Parameter_Specifications
=> New_List
(
927 -- P : Root_Storage_Pool
929 Make_Parameter_Specification
(Loc
,
930 Defining_Identifier
=> Make_Temporary
(Loc
, 'P'),
932 New_Reference_To
(RTE
(RE_Root_Storage_Pool
), Loc
)),
936 Make_Parameter_Specification
(Loc
,
937 Defining_Identifier
=> Addr_Id
,
938 Out_Present
=> Is_Allocate
,
940 New_Reference_To
(RTE
(RE_Address
), Loc
)),
944 Make_Parameter_Specification
(Loc
,
945 Defining_Identifier
=> Size_Id
,
947 New_Reference_To
(RTE
(RE_Storage_Count
), Loc
)),
951 Make_Parameter_Specification
(Loc
,
952 Defining_Identifier
=> Alig_Id
,
954 New_Reference_To
(RTE
(RE_Storage_Count
), Loc
)))),
956 Declarations
=> No_List
,
958 Handled_Statement_Sequence
=>
959 Make_Handled_Sequence_Of_Statements
(Loc
,
960 Statements
=> New_List
(
961 Make_Procedure_Call_Statement
(Loc
,
962 Name
=> New_Reference_To
(Proc_To_Call
, Loc
),
963 Parameter_Associations
=> Actuals
)))));
965 -- The newly generated Allocate / Deallocate becomes the default
966 -- procedure to call when the back end processes the allocation /
970 Set_Procedure_To_Call
(Expr
, Proc_Id
);
972 Set_Procedure_To_Call
(N
, Proc_Id
);
975 end Build_Allocate_Deallocate_Proc
;
977 ------------------------
978 -- Build_Runtime_Call --
979 ------------------------
981 function Build_Runtime_Call
(Loc
: Source_Ptr
; RE
: RE_Id
) return Node_Id
is
983 -- If entity is not available, we can skip making the call (this avoids
984 -- junk duplicated error messages in a number of cases).
986 if not RTE_Available
(RE
) then
987 return Make_Null_Statement
(Loc
);
990 Make_Procedure_Call_Statement
(Loc
,
991 Name
=> New_Reference_To
(RTE
(RE
), Loc
));
993 end Build_Runtime_Call
;
995 ----------------------------
996 -- Build_Task_Array_Image --
997 ----------------------------
999 -- This function generates the body for a function that constructs the
1000 -- image string for a task that is an array component. The function is
1001 -- local to the init proc for the array type, and is called for each one
1002 -- of the components. The constructed image has the form of an indexed
1003 -- component, whose prefix is the outer variable of the array type.
1004 -- The n-dimensional array type has known indexes Index, Index2...
1006 -- Id_Ref is an indexed component form created by the enclosing init proc.
1007 -- Its successive indexes are Val1, Val2, ... which are the loop variables
1008 -- in the loops that call the individual task init proc on each component.
1010 -- The generated function has the following structure:
1012 -- function F return String is
1013 -- Pref : string renames Task_Name;
1014 -- T1 : String := Index1'Image (Val1);
1016 -- Tn : String := indexn'image (Valn);
1017 -- Len : Integer := T1'Length + ... + Tn'Length + n + 1;
1018 -- -- Len includes commas and the end parentheses.
1019 -- Res : String (1..Len);
1020 -- Pos : Integer := Pref'Length;
1023 -- Res (1 .. Pos) := Pref;
1025 -- Res (Pos) := '(';
1027 -- Res (Pos .. Pos + T1'Length - 1) := T1;
1028 -- Pos := Pos + T1'Length;
1029 -- Res (Pos) := '.';
1032 -- Res (Pos .. Pos + Tn'Length - 1) := Tn;
1033 -- Res (Len) := ')';
1038 -- Needless to say, multidimensional arrays of tasks are rare enough that
1039 -- the bulkiness of this code is not really a concern.
1041 function Build_Task_Array_Image
1045 Dyn
: Boolean := False) return Node_Id
1047 Dims
: constant Nat
:= Number_Dimensions
(A_Type
);
1048 -- Number of dimensions for array of tasks
1050 Temps
: array (1 .. Dims
) of Entity_Id
;
1051 -- Array of temporaries to hold string for each index
1057 -- Total length of generated name
1060 -- Running index for substring assignments
1062 Pref
: constant Entity_Id
:= Make_Temporary
(Loc
, 'P');
1063 -- Name of enclosing variable, prefix of resulting name
1066 -- String to hold result
1069 -- Value of successive indexes
1072 -- Expression to compute total size of string
1075 -- Entity for name at one index position
1077 Decls
: constant List_Id
:= New_List
;
1078 Stats
: constant List_Id
:= New_List
;
1081 -- For a dynamic task, the name comes from the target variable. For a
1082 -- static one it is a formal of the enclosing init proc.
1085 Get_Name_String
(Chars
(Entity
(Prefix
(Id_Ref
))));
1087 Make_Object_Declaration
(Loc
,
1088 Defining_Identifier
=> Pref
,
1089 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1091 Make_String_Literal
(Loc
,
1092 Strval
=> String_From_Name_Buffer
)));
1096 Make_Object_Renaming_Declaration
(Loc
,
1097 Defining_Identifier
=> Pref
,
1098 Subtype_Mark
=> New_Occurrence_Of
(Standard_String
, Loc
),
1099 Name
=> Make_Identifier
(Loc
, Name_uTask_Name
)));
1102 Indx
:= First_Index
(A_Type
);
1103 Val
:= First
(Expressions
(Id_Ref
));
1105 for J
in 1 .. Dims
loop
1106 T
:= Make_Temporary
(Loc
, 'T');
1110 Make_Object_Declaration
(Loc
,
1111 Defining_Identifier
=> T
,
1112 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1114 Make_Attribute_Reference
(Loc
,
1115 Attribute_Name
=> Name_Image
,
1116 Prefix
=> New_Occurrence_Of
(Etype
(Indx
), Loc
),
1117 Expressions
=> New_List
(New_Copy_Tree
(Val
)))));
1123 Sum
:= Make_Integer_Literal
(Loc
, Dims
+ 1);
1129 Make_Attribute_Reference
(Loc
,
1130 Attribute_Name
=> Name_Length
,
1131 Prefix
=> New_Occurrence_Of
(Pref
, Loc
),
1132 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1))));
1134 for J
in 1 .. Dims
loop
1139 Make_Attribute_Reference
(Loc
,
1140 Attribute_Name
=> Name_Length
,
1142 New_Occurrence_Of
(Temps
(J
), Loc
),
1143 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1))));
1146 Build_Task_Image_Prefix
(Loc
, Len
, Res
, Pos
, Pref
, Sum
, Decls
, Stats
);
1148 Set_Character_Literal_Name
(Char_Code
(Character'Pos ('(')));
1151 Make_Assignment_Statement
(Loc
,
1153 Make_Indexed_Component
(Loc
,
1154 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1155 Expressions
=> New_List
(New_Occurrence_Of
(Pos
, Loc
))),
1157 Make_Character_Literal
(Loc
,
1159 Char_Literal_Value
=> UI_From_Int
(Character'Pos ('(')))));
1162 Make_Assignment_Statement
(Loc
,
1163 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1166 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1167 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1169 for J
in 1 .. Dims
loop
1172 Make_Assignment_Statement
(Loc
,
1175 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1178 Low_Bound
=> New_Occurrence_Of
(Pos
, Loc
),
1180 Make_Op_Subtract
(Loc
,
1183 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1185 Make_Attribute_Reference
(Loc
,
1186 Attribute_Name
=> Name_Length
,
1188 New_Occurrence_Of
(Temps
(J
), Loc
),
1190 New_List
(Make_Integer_Literal
(Loc
, 1)))),
1191 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1)))),
1193 Expression
=> New_Occurrence_Of
(Temps
(J
), Loc
)));
1197 Make_Assignment_Statement
(Loc
,
1198 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1201 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1203 Make_Attribute_Reference
(Loc
,
1204 Attribute_Name
=> Name_Length
,
1205 Prefix
=> New_Occurrence_Of
(Temps
(J
), Loc
),
1207 New_List
(Make_Integer_Literal
(Loc
, 1))))));
1209 Set_Character_Literal_Name
(Char_Code
(Character'Pos (',')));
1212 Make_Assignment_Statement
(Loc
,
1213 Name
=> Make_Indexed_Component
(Loc
,
1214 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1215 Expressions
=> New_List
(New_Occurrence_Of
(Pos
, Loc
))),
1217 Make_Character_Literal
(Loc
,
1219 Char_Literal_Value
=> UI_From_Int
(Character'Pos (',')))));
1222 Make_Assignment_Statement
(Loc
,
1223 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1226 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1227 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1231 Set_Character_Literal_Name
(Char_Code
(Character'Pos (')')));
1234 Make_Assignment_Statement
(Loc
,
1236 Make_Indexed_Component
(Loc
,
1237 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1238 Expressions
=> New_List
(New_Occurrence_Of
(Len
, Loc
))),
1240 Make_Character_Literal
(Loc
,
1242 Char_Literal_Value
=> UI_From_Int
(Character'Pos (')')))));
1243 return Build_Task_Image_Function
(Loc
, Decls
, Stats
, Res
);
1244 end Build_Task_Array_Image
;
1246 ----------------------------
1247 -- Build_Task_Image_Decls --
1248 ----------------------------
1250 function Build_Task_Image_Decls
1254 In_Init_Proc
: Boolean := False) return List_Id
1256 Decls
: constant List_Id
:= New_List
;
1257 T_Id
: Entity_Id
:= Empty
;
1259 Expr
: Node_Id
:= Empty
;
1260 Fun
: Node_Id
:= Empty
;
1261 Is_Dyn
: constant Boolean :=
1262 Nkind
(Parent
(Id_Ref
)) = N_Assignment_Statement
1264 Nkind
(Expression
(Parent
(Id_Ref
))) = N_Allocator
;
1267 -- If Discard_Names or No_Implicit_Heap_Allocations are in effect,
1268 -- generate a dummy declaration only.
1270 if Restriction_Active
(No_Implicit_Heap_Allocations
)
1271 or else Global_Discard_Names
1273 T_Id
:= Make_Temporary
(Loc
, 'J');
1278 Make_Object_Declaration
(Loc
,
1279 Defining_Identifier
=> T_Id
,
1280 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1282 Make_String_Literal
(Loc
,
1283 Strval
=> String_From_Name_Buffer
)));
1286 if Nkind
(Id_Ref
) = N_Identifier
1287 or else Nkind
(Id_Ref
) = N_Defining_Identifier
1289 -- For a simple variable, the image of the task is built from
1290 -- the name of the variable. To avoid possible conflict with the
1291 -- anonymous type created for a single protected object, add a
1295 Make_Defining_Identifier
(Loc
,
1296 New_External_Name
(Chars
(Id_Ref
), 'T', 1));
1298 Get_Name_String
(Chars
(Id_Ref
));
1301 Make_String_Literal
(Loc
,
1302 Strval
=> String_From_Name_Buffer
);
1304 elsif Nkind
(Id_Ref
) = N_Selected_Component
then
1306 Make_Defining_Identifier
(Loc
,
1307 New_External_Name
(Chars
(Selector_Name
(Id_Ref
)), 'T'));
1308 Fun
:= Build_Task_Record_Image
(Loc
, Id_Ref
, Is_Dyn
);
1310 elsif Nkind
(Id_Ref
) = N_Indexed_Component
then
1312 Make_Defining_Identifier
(Loc
,
1313 New_External_Name
(Chars
(A_Type
), 'N'));
1315 Fun
:= Build_Task_Array_Image
(Loc
, Id_Ref
, A_Type
, Is_Dyn
);
1319 if Present
(Fun
) then
1320 Append
(Fun
, Decls
);
1321 Expr
:= Make_Function_Call
(Loc
,
1322 Name
=> New_Occurrence_Of
(Defining_Entity
(Fun
), Loc
));
1324 if not In_Init_Proc
and then VM_Target
= No_VM
then
1325 Set_Uses_Sec_Stack
(Defining_Entity
(Fun
));
1329 Decl
:= Make_Object_Declaration
(Loc
,
1330 Defining_Identifier
=> T_Id
,
1331 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1332 Constant_Present
=> True,
1333 Expression
=> Expr
);
1335 Append
(Decl
, Decls
);
1337 end Build_Task_Image_Decls
;
1339 -------------------------------
1340 -- Build_Task_Image_Function --
1341 -------------------------------
1343 function Build_Task_Image_Function
1347 Res
: Entity_Id
) return Node_Id
1353 Make_Simple_Return_Statement
(Loc
,
1354 Expression
=> New_Occurrence_Of
(Res
, Loc
)));
1356 Spec
:= Make_Function_Specification
(Loc
,
1357 Defining_Unit_Name
=> Make_Temporary
(Loc
, 'F'),
1358 Result_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
));
1360 -- Calls to 'Image use the secondary stack, which must be cleaned up
1361 -- after the task name is built.
1363 return Make_Subprogram_Body
(Loc
,
1364 Specification
=> Spec
,
1365 Declarations
=> Decls
,
1366 Handled_Statement_Sequence
=>
1367 Make_Handled_Sequence_Of_Statements
(Loc
, Statements
=> Stats
));
1368 end Build_Task_Image_Function
;
1370 -----------------------------
1371 -- Build_Task_Image_Prefix --
1372 -----------------------------
1374 procedure Build_Task_Image_Prefix
1376 Len
: out Entity_Id
;
1377 Res
: out Entity_Id
;
1378 Pos
: out Entity_Id
;
1385 Len
:= Make_Temporary
(Loc
, 'L', Sum
);
1388 Make_Object_Declaration
(Loc
,
1389 Defining_Identifier
=> Len
,
1390 Object_Definition
=> New_Occurrence_Of
(Standard_Integer
, Loc
),
1391 Expression
=> Sum
));
1393 Res
:= Make_Temporary
(Loc
, 'R');
1396 Make_Object_Declaration
(Loc
,
1397 Defining_Identifier
=> Res
,
1398 Object_Definition
=>
1399 Make_Subtype_Indication
(Loc
,
1400 Subtype_Mark
=> New_Occurrence_Of
(Standard_String
, Loc
),
1402 Make_Index_Or_Discriminant_Constraint
(Loc
,
1406 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
1407 High_Bound
=> New_Occurrence_Of
(Len
, Loc
)))))));
1409 Pos
:= Make_Temporary
(Loc
, 'P');
1412 Make_Object_Declaration
(Loc
,
1413 Defining_Identifier
=> Pos
,
1414 Object_Definition
=> New_Occurrence_Of
(Standard_Integer
, Loc
)));
1416 -- Pos := Prefix'Length;
1419 Make_Assignment_Statement
(Loc
,
1420 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1422 Make_Attribute_Reference
(Loc
,
1423 Attribute_Name
=> Name_Length
,
1424 Prefix
=> New_Occurrence_Of
(Prefix
, Loc
),
1425 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1)))));
1427 -- Res (1 .. Pos) := Prefix;
1430 Make_Assignment_Statement
(Loc
,
1433 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1436 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
1437 High_Bound
=> New_Occurrence_Of
(Pos
, Loc
))),
1439 Expression
=> New_Occurrence_Of
(Prefix
, Loc
)));
1442 Make_Assignment_Statement
(Loc
,
1443 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1446 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1447 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1448 end Build_Task_Image_Prefix
;
1450 -----------------------------
1451 -- Build_Task_Record_Image --
1452 -----------------------------
1454 function Build_Task_Record_Image
1457 Dyn
: Boolean := False) return Node_Id
1460 -- Total length of generated name
1463 -- Index into result
1466 -- String to hold result
1468 Pref
: constant Entity_Id
:= Make_Temporary
(Loc
, 'P');
1469 -- Name of enclosing variable, prefix of resulting name
1472 -- Expression to compute total size of string
1475 -- Entity for selector name
1477 Decls
: constant List_Id
:= New_List
;
1478 Stats
: constant List_Id
:= New_List
;
1481 -- For a dynamic task, the name comes from the target variable. For a
1482 -- static one it is a formal of the enclosing init proc.
1485 Get_Name_String
(Chars
(Entity
(Prefix
(Id_Ref
))));
1487 Make_Object_Declaration
(Loc
,
1488 Defining_Identifier
=> Pref
,
1489 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1491 Make_String_Literal
(Loc
,
1492 Strval
=> String_From_Name_Buffer
)));
1496 Make_Object_Renaming_Declaration
(Loc
,
1497 Defining_Identifier
=> Pref
,
1498 Subtype_Mark
=> New_Occurrence_Of
(Standard_String
, Loc
),
1499 Name
=> Make_Identifier
(Loc
, Name_uTask_Name
)));
1502 Sel
:= Make_Temporary
(Loc
, 'S');
1504 Get_Name_String
(Chars
(Selector_Name
(Id_Ref
)));
1507 Make_Object_Declaration
(Loc
,
1508 Defining_Identifier
=> Sel
,
1509 Object_Definition
=> New_Occurrence_Of
(Standard_String
, Loc
),
1511 Make_String_Literal
(Loc
,
1512 Strval
=> String_From_Name_Buffer
)));
1514 Sum
:= Make_Integer_Literal
(Loc
, Nat
(Name_Len
+ 1));
1520 Make_Attribute_Reference
(Loc
,
1521 Attribute_Name
=> Name_Length
,
1523 New_Occurrence_Of
(Pref
, Loc
),
1524 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, 1))));
1526 Build_Task_Image_Prefix
(Loc
, Len
, Res
, Pos
, Pref
, Sum
, Decls
, Stats
);
1528 Set_Character_Literal_Name
(Char_Code
(Character'Pos ('.')));
1530 -- Res (Pos) := '.';
1533 Make_Assignment_Statement
(Loc
,
1534 Name
=> Make_Indexed_Component
(Loc
,
1535 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1536 Expressions
=> New_List
(New_Occurrence_Of
(Pos
, Loc
))),
1538 Make_Character_Literal
(Loc
,
1540 Char_Literal_Value
=>
1541 UI_From_Int
(Character'Pos ('.')))));
1544 Make_Assignment_Statement
(Loc
,
1545 Name
=> New_Occurrence_Of
(Pos
, Loc
),
1548 Left_Opnd
=> New_Occurrence_Of
(Pos
, Loc
),
1549 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1))));
1551 -- Res (Pos .. Len) := Selector;
1554 Make_Assignment_Statement
(Loc
,
1555 Name
=> Make_Slice
(Loc
,
1556 Prefix
=> New_Occurrence_Of
(Res
, Loc
),
1559 Low_Bound
=> New_Occurrence_Of
(Pos
, Loc
),
1560 High_Bound
=> New_Occurrence_Of
(Len
, Loc
))),
1561 Expression
=> New_Occurrence_Of
(Sel
, Loc
)));
1563 return Build_Task_Image_Function
(Loc
, Decls
, Stats
, Res
);
1564 end Build_Task_Record_Image
;
1566 ----------------------------------
1567 -- Component_May_Be_Bit_Aligned --
1568 ----------------------------------
1570 function Component_May_Be_Bit_Aligned
(Comp
: Entity_Id
) return Boolean is
1574 -- If no component clause, then everything is fine, since the back end
1575 -- never bit-misaligns by default, even if there is a pragma Packed for
1578 if No
(Comp
) or else No
(Component_Clause
(Comp
)) then
1582 UT
:= Underlying_Type
(Etype
(Comp
));
1584 -- It is only array and record types that cause trouble
1586 if not Is_Record_Type
(UT
) and then not Is_Array_Type
(UT
) then
1589 -- If we know that we have a small (64 bits or less) record or small
1590 -- bit-packed array, then everything is fine, since the back end can
1591 -- handle these cases correctly.
1593 elsif Esize
(Comp
) <= 64
1594 and then (Is_Record_Type
(UT
) or else Is_Bit_Packed_Array
(UT
))
1598 -- Otherwise if the component is not byte aligned, we know we have the
1599 -- nasty unaligned case.
1601 elsif Normalized_First_Bit
(Comp
) /= Uint_0
1602 or else Esize
(Comp
) mod System_Storage_Unit
/= Uint_0
1606 -- If we are large and byte aligned, then OK at this level
1611 end Component_May_Be_Bit_Aligned
;
1613 -----------------------------------
1614 -- Corresponding_Runtime_Package --
1615 -----------------------------------
1617 function Corresponding_Runtime_Package
(Typ
: Entity_Id
) return RTU_Id
is
1618 Pkg_Id
: RTU_Id
:= RTU_Null
;
1621 pragma Assert
(Is_Concurrent_Type
(Typ
));
1623 if Ekind
(Typ
) in Protected_Kind
then
1624 if Has_Entries
(Typ
)
1626 -- A protected type without entries that covers an interface and
1627 -- overrides the abstract routines with protected procedures is
1628 -- considered equivalent to a protected type with entries in the
1629 -- context of dispatching select statements. It is sufficient to
1630 -- check for the presence of an interface list in the declaration
1631 -- node to recognize this case.
1633 or else Present
(Interface_List
(Parent
(Typ
)))
1635 (((Has_Attach_Handler
(Typ
) and then not Restricted_Profile
)
1636 or else Has_Interrupt_Handler
(Typ
))
1637 and then not Restriction_Active
(No_Dynamic_Attachment
))
1640 or else Restriction_Active
(No_Entry_Queue
) = False
1641 or else Number_Entries
(Typ
) > 1
1642 or else (Has_Attach_Handler
(Typ
)
1643 and then not Restricted_Profile
)
1645 Pkg_Id
:= System_Tasking_Protected_Objects_Entries
;
1647 Pkg_Id
:= System_Tasking_Protected_Objects_Single_Entry
;
1651 Pkg_Id
:= System_Tasking_Protected_Objects
;
1656 end Corresponding_Runtime_Package
;
1658 -------------------------------
1659 -- Convert_To_Actual_Subtype --
1660 -------------------------------
1662 procedure Convert_To_Actual_Subtype
(Exp
: Entity_Id
) is
1666 Act_ST
:= Get_Actual_Subtype
(Exp
);
1668 if Act_ST
= Etype
(Exp
) then
1671 Rewrite
(Exp
, Convert_To
(Act_ST
, Relocate_Node
(Exp
)));
1672 Analyze_And_Resolve
(Exp
, Act_ST
);
1674 end Convert_To_Actual_Subtype
;
1676 -----------------------------------
1677 -- Current_Sem_Unit_Declarations --
1678 -----------------------------------
1680 function Current_Sem_Unit_Declarations
return List_Id
is
1681 U
: Node_Id
:= Unit
(Cunit
(Current_Sem_Unit
));
1685 -- If the current unit is a package body, locate the visible
1686 -- declarations of the package spec.
1688 if Nkind
(U
) = N_Package_Body
then
1689 U
:= Unit
(Library_Unit
(Cunit
(Current_Sem_Unit
)));
1692 if Nkind
(U
) = N_Package_Declaration
then
1693 U
:= Specification
(U
);
1694 Decls
:= Visible_Declarations
(U
);
1698 Set_Visible_Declarations
(U
, Decls
);
1702 Decls
:= Declarations
(U
);
1706 Set_Declarations
(U
, Decls
);
1711 end Current_Sem_Unit_Declarations
;
1713 -----------------------
1714 -- Duplicate_Subexpr --
1715 -----------------------
1717 function Duplicate_Subexpr
1719 Name_Req
: Boolean := False) return Node_Id
1722 Remove_Side_Effects
(Exp
, Name_Req
);
1723 return New_Copy_Tree
(Exp
);
1724 end Duplicate_Subexpr
;
1726 ---------------------------------
1727 -- Duplicate_Subexpr_No_Checks --
1728 ---------------------------------
1730 function Duplicate_Subexpr_No_Checks
1732 Name_Req
: Boolean := False) return Node_Id
1736 Remove_Side_Effects
(Exp
, Name_Req
);
1737 New_Exp
:= New_Copy_Tree
(Exp
);
1738 Remove_Checks
(New_Exp
);
1740 end Duplicate_Subexpr_No_Checks
;
1742 -----------------------------------
1743 -- Duplicate_Subexpr_Move_Checks --
1744 -----------------------------------
1746 function Duplicate_Subexpr_Move_Checks
1748 Name_Req
: Boolean := False) return Node_Id
1752 Remove_Side_Effects
(Exp
, Name_Req
);
1753 New_Exp
:= New_Copy_Tree
(Exp
);
1754 Remove_Checks
(Exp
);
1756 end Duplicate_Subexpr_Move_Checks
;
1758 --------------------
1759 -- Ensure_Defined --
1760 --------------------
1762 procedure Ensure_Defined
(Typ
: Entity_Id
; N
: Node_Id
) is
1766 -- An itype reference must only be created if this is a local itype, so
1767 -- that gigi can elaborate it on the proper objstack.
1769 if Is_Itype
(Typ
) and then Scope
(Typ
) = Current_Scope
then
1770 IR
:= Make_Itype_Reference
(Sloc
(N
));
1771 Set_Itype
(IR
, Typ
);
1772 Insert_Action
(N
, IR
);
1780 function Entity_Of
(N
: Node_Id
) return Entity_Id
is
1786 if Is_Entity_Name
(N
) then
1789 -- Follow a possible chain of renamings to reach the root renamed
1792 while Present
(Renamed_Object
(Id
)) loop
1793 if Is_Entity_Name
(Renamed_Object
(Id
)) then
1794 Id
:= Entity
(Renamed_Object
(Id
));
1805 --------------------
1806 -- Entry_Names_OK --
1807 --------------------
1809 function Entry_Names_OK
return Boolean is
1812 not Restricted_Profile
1813 and then not Global_Discard_Names
1814 and then not Restriction_Active
(No_Implicit_Heap_Allocations
)
1815 and then not Restriction_Active
(No_Local_Allocators
);
1822 procedure Evaluate_Name
(Nam
: Node_Id
) is
1823 K
: constant Node_Kind
:= Nkind
(Nam
);
1826 -- For an explicit dereference, we simply force the evaluation of the
1827 -- name expression. The dereference provides a value that is the address
1828 -- for the renamed object, and it is precisely this value that we want
1831 if K
= N_Explicit_Dereference
then
1832 Force_Evaluation
(Prefix
(Nam
));
1834 -- For a selected component, we simply evaluate the prefix
1836 elsif K
= N_Selected_Component
then
1837 Evaluate_Name
(Prefix
(Nam
));
1839 -- For an indexed component, or an attribute reference, we evaluate the
1840 -- prefix, which is itself a name, recursively, and then force the
1841 -- evaluation of all the subscripts (or attribute expressions).
1843 elsif Nkind_In
(K
, N_Indexed_Component
, N_Attribute_Reference
) then
1844 Evaluate_Name
(Prefix
(Nam
));
1850 E
:= First
(Expressions
(Nam
));
1851 while Present
(E
) loop
1852 Force_Evaluation
(E
);
1854 if Original_Node
(E
) /= E
then
1855 Set_Do_Range_Check
(E
, Do_Range_Check
(Original_Node
(E
)));
1862 -- For a slice, we evaluate the prefix, as for the indexed component
1863 -- case and then, if there is a range present, either directly or as the
1864 -- constraint of a discrete subtype indication, we evaluate the two
1865 -- bounds of this range.
1867 elsif K
= N_Slice
then
1868 Evaluate_Name
(Prefix
(Nam
));
1871 DR
: constant Node_Id
:= Discrete_Range
(Nam
);
1876 if Nkind
(DR
) = N_Range
then
1877 Force_Evaluation
(Low_Bound
(DR
));
1878 Force_Evaluation
(High_Bound
(DR
));
1880 elsif Nkind
(DR
) = N_Subtype_Indication
then
1881 Constr
:= Constraint
(DR
);
1883 if Nkind
(Constr
) = N_Range_Constraint
then
1884 Rexpr
:= Range_Expression
(Constr
);
1886 Force_Evaluation
(Low_Bound
(Rexpr
));
1887 Force_Evaluation
(High_Bound
(Rexpr
));
1892 -- For a type conversion, the expression of the conversion must be the
1893 -- name of an object, and we simply need to evaluate this name.
1895 elsif K
= N_Type_Conversion
then
1896 Evaluate_Name
(Expression
(Nam
));
1898 -- For a function call, we evaluate the call
1900 elsif K
= N_Function_Call
then
1901 Force_Evaluation
(Nam
);
1903 -- The remaining cases are direct name, operator symbol and character
1904 -- literal. In all these cases, we do nothing, since we want to
1905 -- reevaluate each time the renamed object is used.
1912 ---------------------
1913 -- Evolve_And_Then --
1914 ---------------------
1916 procedure Evolve_And_Then
(Cond
: in out Node_Id
; Cond1
: Node_Id
) is
1922 Make_And_Then
(Sloc
(Cond1
),
1924 Right_Opnd
=> Cond1
);
1926 end Evolve_And_Then
;
1928 --------------------
1929 -- Evolve_Or_Else --
1930 --------------------
1932 procedure Evolve_Or_Else
(Cond
: in out Node_Id
; Cond1
: Node_Id
) is
1938 Make_Or_Else
(Sloc
(Cond1
),
1940 Right_Opnd
=> Cond1
);
1944 ------------------------------
1945 -- Expand_Subtype_From_Expr --
1946 ------------------------------
1948 -- This function is applicable for both static and dynamic allocation of
1949 -- objects which are constrained by an initial expression. Basically it
1950 -- transforms an unconstrained subtype indication into a constrained one.
1952 -- The expression may also be transformed in certain cases in order to
1953 -- avoid multiple evaluation. In the static allocation case, the general
1958 -- is transformed into
1960 -- Val : Constrained_Subtype_of_T := Maybe_Modified_Expr;
1962 -- Here are the main cases :
1964 -- <if Expr is a Slice>
1965 -- Val : T ([Index_Subtype (Expr)]) := Expr;
1967 -- <elsif Expr is a String Literal>
1968 -- Val : T (T'First .. T'First + Length (string literal) - 1) := Expr;
1970 -- <elsif Expr is Constrained>
1971 -- subtype T is Type_Of_Expr
1974 -- <elsif Expr is an entity_name>
1975 -- Val : T (constraints taken from Expr) := Expr;
1978 -- type Axxx is access all T;
1979 -- Rval : Axxx := Expr'ref;
1980 -- Val : T (constraints taken from Rval) := Rval.all;
1982 -- ??? note: when the Expression is allocated in the secondary stack
1983 -- we could use it directly instead of copying it by declaring
1984 -- Val : T (...) renames Rval.all
1986 procedure Expand_Subtype_From_Expr
1988 Unc_Type
: Entity_Id
;
1989 Subtype_Indic
: Node_Id
;
1992 Loc
: constant Source_Ptr
:= Sloc
(N
);
1993 Exp_Typ
: constant Entity_Id
:= Etype
(Exp
);
1997 -- In general we cannot build the subtype if expansion is disabled,
1998 -- because internal entities may not have been defined. However, to
1999 -- avoid some cascaded errors, we try to continue when the expression is
2000 -- an array (or string), because it is safe to compute the bounds. It is
2001 -- in fact required to do so even in a generic context, because there
2002 -- may be constants that depend on the bounds of a string literal, both
2003 -- standard string types and more generally arrays of characters.
2005 if not Expander_Active
2006 and then (No
(Etype
(Exp
)) or else not Is_String_Type
(Etype
(Exp
)))
2011 if Nkind
(Exp
) = N_Slice
then
2013 Slice_Type
: constant Entity_Id
:= Etype
(First_Index
(Exp_Typ
));
2016 Rewrite
(Subtype_Indic
,
2017 Make_Subtype_Indication
(Loc
,
2018 Subtype_Mark
=> New_Reference_To
(Unc_Type
, Loc
),
2020 Make_Index_Or_Discriminant_Constraint
(Loc
,
2021 Constraints
=> New_List
2022 (New_Reference_To
(Slice_Type
, Loc
)))));
2024 -- This subtype indication may be used later for constraint checks
2025 -- we better make sure that if a variable was used as a bound of
2026 -- of the original slice, its value is frozen.
2028 Force_Evaluation
(Low_Bound
(Scalar_Range
(Slice_Type
)));
2029 Force_Evaluation
(High_Bound
(Scalar_Range
(Slice_Type
)));
2032 elsif Ekind
(Exp_Typ
) = E_String_Literal_Subtype
then
2033 Rewrite
(Subtype_Indic
,
2034 Make_Subtype_Indication
(Loc
,
2035 Subtype_Mark
=> New_Reference_To
(Unc_Type
, Loc
),
2037 Make_Index_Or_Discriminant_Constraint
(Loc
,
2038 Constraints
=> New_List
(
2039 Make_Literal_Range
(Loc
,
2040 Literal_Typ
=> Exp_Typ
)))));
2042 -- If the type of the expression is an internally generated type it
2043 -- may not be necessary to create a new subtype. However there are two
2044 -- exceptions: references to the current instances, and aliased array
2045 -- object declarations for which the backend needs to create a template.
2047 elsif Is_Constrained
(Exp_Typ
)
2048 and then not Is_Class_Wide_Type
(Unc_Type
)
2050 (Nkind
(N
) /= N_Object_Declaration
2051 or else not Is_Entity_Name
(Expression
(N
))
2052 or else not Comes_From_Source
(Entity
(Expression
(N
)))
2053 or else not Is_Array_Type
(Exp_Typ
)
2054 or else not Aliased_Present
(N
))
2056 if Is_Itype
(Exp_Typ
) then
2058 -- Within an initialization procedure, a selected component
2059 -- denotes a component of the enclosing record, and it appears as
2060 -- an actual in a call to its own initialization procedure. If
2061 -- this component depends on the outer discriminant, we must
2062 -- generate the proper actual subtype for it.
2064 if Nkind
(Exp
) = N_Selected_Component
2065 and then Within_Init_Proc
2068 Decl
: constant Node_Id
:=
2069 Build_Actual_Subtype_Of_Component
(Exp_Typ
, Exp
);
2071 if Present
(Decl
) then
2072 Insert_Action
(N
, Decl
);
2073 T
:= Defining_Identifier
(Decl
);
2079 -- No need to generate a new subtype
2086 T
:= Make_Temporary
(Loc
, 'T');
2089 Make_Subtype_Declaration
(Loc
,
2090 Defining_Identifier
=> T
,
2091 Subtype_Indication
=> New_Reference_To
(Exp_Typ
, Loc
)));
2093 -- This type is marked as an itype even though it has an explicit
2094 -- declaration since otherwise Is_Generic_Actual_Type can get
2095 -- set, resulting in the generation of spurious errors. (See
2096 -- sem_ch8.Analyze_Package_Renaming and sem_type.covers)
2099 Set_Associated_Node_For_Itype
(T
, Exp
);
2102 Rewrite
(Subtype_Indic
, New_Reference_To
(T
, Loc
));
2104 -- Nothing needs to be done for private types with unknown discriminants
2105 -- if the underlying type is not an unconstrained composite type or it
2106 -- is an unchecked union.
2108 elsif Is_Private_Type
(Unc_Type
)
2109 and then Has_Unknown_Discriminants
(Unc_Type
)
2110 and then (not Is_Composite_Type
(Underlying_Type
(Unc_Type
))
2111 or else Is_Constrained
(Underlying_Type
(Unc_Type
))
2112 or else Is_Unchecked_Union
(Underlying_Type
(Unc_Type
)))
2116 -- Case of derived type with unknown discriminants where the parent type
2117 -- also has unknown discriminants.
2119 elsif Is_Record_Type
(Unc_Type
)
2120 and then not Is_Class_Wide_Type
(Unc_Type
)
2121 and then Has_Unknown_Discriminants
(Unc_Type
)
2122 and then Has_Unknown_Discriminants
(Underlying_Type
(Unc_Type
))
2124 -- Nothing to be done if no underlying record view available
2126 if No
(Underlying_Record_View
(Unc_Type
)) then
2129 -- Otherwise use the Underlying_Record_View to create the proper
2130 -- constrained subtype for an object of a derived type with unknown
2134 Remove_Side_Effects
(Exp
);
2135 Rewrite
(Subtype_Indic
,
2136 Make_Subtype_From_Expr
(Exp
, Underlying_Record_View
(Unc_Type
)));
2139 -- Renamings of class-wide interface types require no equivalent
2140 -- constrained type declarations because we only need to reference
2141 -- the tag component associated with the interface. The same is
2142 -- presumably true for class-wide types in general, so this test
2143 -- is broadened to include all class-wide renamings, which also
2144 -- avoids cases of unbounded recursion in Remove_Side_Effects.
2145 -- (Is this really correct, or are there some cases of class-wide
2146 -- renamings that require action in this procedure???)
2149 and then Nkind
(N
) = N_Object_Renaming_Declaration
2150 and then Is_Class_Wide_Type
(Unc_Type
)
2154 -- In Ada 95 nothing to be done if the type of the expression is limited
2155 -- because in this case the expression cannot be copied, and its use can
2156 -- only be by reference.
2158 -- In Ada 2005 the context can be an object declaration whose expression
2159 -- is a function that returns in place. If the nominal subtype has
2160 -- unknown discriminants, the call still provides constraints on the
2161 -- object, and we have to create an actual subtype from it.
2163 -- If the type is class-wide, the expression is dynamically tagged and
2164 -- we do not create an actual subtype either. Ditto for an interface.
2165 -- For now this applies only if the type is immutably limited, and the
2166 -- function being called is build-in-place. This will have to be revised
2167 -- when build-in-place functions are generalized to other types.
2169 elsif Is_Immutably_Limited_Type
(Exp_Typ
)
2171 (Is_Class_Wide_Type
(Exp_Typ
)
2172 or else Is_Interface
(Exp_Typ
)
2173 or else not Has_Unknown_Discriminants
(Exp_Typ
)
2174 or else not Is_Composite_Type
(Unc_Type
))
2178 -- For limited objects initialized with build in place function calls,
2179 -- nothing to be done; otherwise we prematurely introduce an N_Reference
2180 -- node in the expression initializing the object, which breaks the
2181 -- circuitry that detects and adds the additional arguments to the
2184 elsif Is_Build_In_Place_Function_Call
(Exp
) then
2188 Remove_Side_Effects
(Exp
);
2189 Rewrite
(Subtype_Indic
,
2190 Make_Subtype_From_Expr
(Exp
, Unc_Type
));
2192 end Expand_Subtype_From_Expr
;
2194 ------------------------
2195 -- Find_Interface_ADT --
2196 ------------------------
2198 function Find_Interface_ADT
2200 Iface
: Entity_Id
) return Elmt_Id
2203 Typ
: Entity_Id
:= T
;
2206 pragma Assert
(Is_Interface
(Iface
));
2208 -- Handle private types
2210 if Has_Private_Declaration
(Typ
) and then Present
(Full_View
(Typ
)) then
2211 Typ
:= Full_View
(Typ
);
2214 -- Handle access types
2216 if Is_Access_Type
(Typ
) then
2217 Typ
:= Designated_Type
(Typ
);
2220 -- Handle task and protected types implementing interfaces
2222 if Is_Concurrent_Type
(Typ
) then
2223 Typ
:= Corresponding_Record_Type
(Typ
);
2227 (not Is_Class_Wide_Type
(Typ
)
2228 and then Ekind
(Typ
) /= E_Incomplete_Type
);
2230 if Is_Ancestor
(Iface
, Typ
, Use_Full_View
=> True) then
2231 return First_Elmt
(Access_Disp_Table
(Typ
));
2234 ADT
:= Next_Elmt
(Next_Elmt
(First_Elmt
(Access_Disp_Table
(Typ
))));
2236 and then Present
(Related_Type
(Node
(ADT
)))
2237 and then Related_Type
(Node
(ADT
)) /= Iface
2238 and then not Is_Ancestor
(Iface
, Related_Type
(Node
(ADT
)),
2239 Use_Full_View
=> True)
2244 pragma Assert
(Present
(Related_Type
(Node
(ADT
))));
2247 end Find_Interface_ADT
;
2249 ------------------------
2250 -- Find_Interface_Tag --
2251 ------------------------
2253 function Find_Interface_Tag
2255 Iface
: Entity_Id
) return Entity_Id
2258 Found
: Boolean := False;
2259 Typ
: Entity_Id
:= T
;
2261 procedure Find_Tag
(Typ
: Entity_Id
);
2262 -- Internal subprogram used to recursively climb to the ancestors
2268 procedure Find_Tag
(Typ
: Entity_Id
) is
2273 -- This routine does not handle the case in which the interface is an
2274 -- ancestor of Typ. That case is handled by the enclosing subprogram.
2276 pragma Assert
(Typ
/= Iface
);
2278 -- Climb to the root type handling private types
2280 if Present
(Full_View
(Etype
(Typ
))) then
2281 if Full_View
(Etype
(Typ
)) /= Typ
then
2282 Find_Tag
(Full_View
(Etype
(Typ
)));
2285 elsif Etype
(Typ
) /= Typ
then
2286 Find_Tag
(Etype
(Typ
));
2289 -- Traverse the list of interfaces implemented by the type
2292 and then Present
(Interfaces
(Typ
))
2293 and then not (Is_Empty_Elmt_List
(Interfaces
(Typ
)))
2295 -- Skip the tag associated with the primary table
2297 pragma Assert
(Etype
(First_Tag_Component
(Typ
)) = RTE
(RE_Tag
));
2298 AI_Tag
:= Next_Tag_Component
(First_Tag_Component
(Typ
));
2299 pragma Assert
(Present
(AI_Tag
));
2301 AI_Elmt
:= First_Elmt
(Interfaces
(Typ
));
2302 while Present
(AI_Elmt
) loop
2303 AI
:= Node
(AI_Elmt
);
2306 or else Is_Ancestor
(Iface
, AI
, Use_Full_View
=> True)
2312 AI_Tag
:= Next_Tag_Component
(AI_Tag
);
2313 Next_Elmt
(AI_Elmt
);
2318 -- Start of processing for Find_Interface_Tag
2321 pragma Assert
(Is_Interface
(Iface
));
2323 -- Handle access types
2325 if Is_Access_Type
(Typ
) then
2326 Typ
:= Designated_Type
(Typ
);
2329 -- Handle class-wide types
2331 if Is_Class_Wide_Type
(Typ
) then
2332 Typ
:= Root_Type
(Typ
);
2335 -- Handle private types
2337 if Has_Private_Declaration
(Typ
) and then Present
(Full_View
(Typ
)) then
2338 Typ
:= Full_View
(Typ
);
2341 -- Handle entities from the limited view
2343 if Ekind
(Typ
) = E_Incomplete_Type
then
2344 pragma Assert
(Present
(Non_Limited_View
(Typ
)));
2345 Typ
:= Non_Limited_View
(Typ
);
2348 -- Handle task and protected types implementing interfaces
2350 if Is_Concurrent_Type
(Typ
) then
2351 Typ
:= Corresponding_Record_Type
(Typ
);
2354 -- If the interface is an ancestor of the type, then it shared the
2355 -- primary dispatch table.
2357 if Is_Ancestor
(Iface
, Typ
, Use_Full_View
=> True) then
2358 pragma Assert
(Etype
(First_Tag_Component
(Typ
)) = RTE
(RE_Tag
));
2359 return First_Tag_Component
(Typ
);
2361 -- Otherwise we need to search for its associated tag component
2365 pragma Assert
(Found
);
2368 end Find_Interface_Tag
;
2374 function Find_Prim_Op
(T
: Entity_Id
; Name
: Name_Id
) return Entity_Id
is
2376 Typ
: Entity_Id
:= T
;
2380 if Is_Class_Wide_Type
(Typ
) then
2381 Typ
:= Root_Type
(Typ
);
2384 Typ
:= Underlying_Type
(Typ
);
2386 -- Loop through primitive operations
2388 Prim
:= First_Elmt
(Primitive_Operations
(Typ
));
2389 while Present
(Prim
) loop
2392 -- We can retrieve primitive operations by name if it is an internal
2393 -- name. For equality we must check that both of its operands have
2394 -- the same type, to avoid confusion with user-defined equalities
2395 -- than may have a non-symmetric signature.
2397 exit when Chars
(Op
) = Name
2400 or else Etype
(First_Formal
(Op
)) = Etype
(Last_Formal
(Op
)));
2404 -- Raise Program_Error if no primitive found
2407 raise Program_Error
;
2418 function Find_Prim_Op
2420 Name
: TSS_Name_Type
) return Entity_Id
2422 Inher_Op
: Entity_Id
:= Empty
;
2423 Own_Op
: Entity_Id
:= Empty
;
2424 Prim_Elmt
: Elmt_Id
;
2425 Prim_Id
: Entity_Id
;
2426 Typ
: Entity_Id
:= T
;
2429 if Is_Class_Wide_Type
(Typ
) then
2430 Typ
:= Root_Type
(Typ
);
2433 Typ
:= Underlying_Type
(Typ
);
2435 -- This search is based on the assertion that the dispatching version
2436 -- of the TSS routine always precedes the real primitive.
2438 Prim_Elmt
:= First_Elmt
(Primitive_Operations
(Typ
));
2439 while Present
(Prim_Elmt
) loop
2440 Prim_Id
:= Node
(Prim_Elmt
);
2442 if Is_TSS
(Prim_Id
, Name
) then
2443 if Present
(Alias
(Prim_Id
)) then
2444 Inher_Op
:= Prim_Id
;
2450 Next_Elmt
(Prim_Elmt
);
2453 if Present
(Own_Op
) then
2455 elsif Present
(Inher_Op
) then
2458 raise Program_Error
;
2462 ----------------------------
2463 -- Find_Protection_Object --
2464 ----------------------------
2466 function Find_Protection_Object
(Scop
: Entity_Id
) return Entity_Id
is
2471 while Present
(S
) loop
2472 if Ekind_In
(S
, E_Entry
, E_Entry_Family
, E_Function
, E_Procedure
)
2473 and then Present
(Protection_Object
(S
))
2475 return Protection_Object
(S
);
2481 -- If we do not find a Protection object in the scope chain, then
2482 -- something has gone wrong, most likely the object was never created.
2484 raise Program_Error
;
2485 end Find_Protection_Object
;
2487 --------------------------
2488 -- Find_Protection_Type --
2489 --------------------------
2491 function Find_Protection_Type
(Conc_Typ
: Entity_Id
) return Entity_Id
is
2493 Typ
: Entity_Id
:= Conc_Typ
;
2496 if Is_Concurrent_Type
(Typ
) then
2497 Typ
:= Corresponding_Record_Type
(Typ
);
2500 -- Since restriction violations are not considered serious errors, the
2501 -- expander remains active, but may leave the corresponding record type
2502 -- malformed. In such cases, component _object is not available so do
2505 if not Analyzed
(Typ
) then
2509 Comp
:= First_Component
(Typ
);
2510 while Present
(Comp
) loop
2511 if Chars
(Comp
) = Name_uObject
then
2512 return Base_Type
(Etype
(Comp
));
2515 Next_Component
(Comp
);
2518 -- The corresponding record of a protected type should always have an
2521 raise Program_Error
;
2522 end Find_Protection_Type
;
2524 ----------------------
2525 -- Force_Evaluation --
2526 ----------------------
2528 procedure Force_Evaluation
(Exp
: Node_Id
; Name_Req
: Boolean := False) is
2530 Remove_Side_Effects
(Exp
, Name_Req
, Variable_Ref
=> True);
2531 end Force_Evaluation
;
2533 ---------------------------------
2534 -- Fully_Qualified_Name_String --
2535 ---------------------------------
2537 function Fully_Qualified_Name_String
2539 Append_NUL
: Boolean := True) return String_Id
2541 procedure Internal_Full_Qualified_Name
(E
: Entity_Id
);
2542 -- Compute recursively the qualified name without NUL at the end, adding
2543 -- it to the currently started string being generated
2545 ----------------------------------
2546 -- Internal_Full_Qualified_Name --
2547 ----------------------------------
2549 procedure Internal_Full_Qualified_Name
(E
: Entity_Id
) is
2553 -- Deal properly with child units
2555 if Nkind
(E
) = N_Defining_Program_Unit_Name
then
2556 Ent
:= Defining_Identifier
(E
);
2561 -- Compute qualification recursively (only "Standard" has no scope)
2563 if Present
(Scope
(Scope
(Ent
))) then
2564 Internal_Full_Qualified_Name
(Scope
(Ent
));
2565 Store_String_Char
(Get_Char_Code
('.'));
2568 -- Every entity should have a name except some expanded blocks
2569 -- don't bother about those.
2571 if Chars
(Ent
) = No_Name
then
2575 -- Generates the entity name in upper case
2577 Get_Decoded_Name_String
(Chars
(Ent
));
2579 Store_String_Chars
(Name_Buffer
(1 .. Name_Len
));
2581 end Internal_Full_Qualified_Name
;
2583 -- Start of processing for Full_Qualified_Name
2587 Internal_Full_Qualified_Name
(E
);
2590 Store_String_Char
(Get_Char_Code
(ASCII
.NUL
));
2594 end Fully_Qualified_Name_String
;
2596 ------------------------
2597 -- Generate_Poll_Call --
2598 ------------------------
2600 procedure Generate_Poll_Call
(N
: Node_Id
) is
2602 -- No poll call if polling not active
2604 if not Polling_Required
then
2607 -- Otherwise generate require poll call
2610 Insert_Before_And_Analyze
(N
,
2611 Make_Procedure_Call_Statement
(Sloc
(N
),
2612 Name
=> New_Occurrence_Of
(RTE
(RE_Poll
), Sloc
(N
))));
2614 end Generate_Poll_Call
;
2616 ---------------------------------
2617 -- Get_Current_Value_Condition --
2618 ---------------------------------
2620 -- Note: the implementation of this procedure is very closely tied to the
2621 -- implementation of Set_Current_Value_Condition. In the Get procedure, we
2622 -- interpret Current_Value fields set by the Set procedure, so the two
2623 -- procedures need to be closely coordinated.
2625 procedure Get_Current_Value_Condition
2630 Loc
: constant Source_Ptr
:= Sloc
(Var
);
2631 Ent
: constant Entity_Id
:= Entity
(Var
);
2633 procedure Process_Current_Value_Condition
2636 -- N is an expression which holds either True (S = True) or False (S =
2637 -- False) in the condition. This procedure digs out the expression and
2638 -- if it refers to Ent, sets Op and Val appropriately.
2640 -------------------------------------
2641 -- Process_Current_Value_Condition --
2642 -------------------------------------
2644 procedure Process_Current_Value_Condition
2655 -- Deal with NOT operators, inverting sense
2657 while Nkind
(Cond
) = N_Op_Not
loop
2658 Cond
:= Right_Opnd
(Cond
);
2662 -- Deal with AND THEN and AND cases
2664 if Nkind_In
(Cond
, N_And_Then
, N_Op_And
) then
2666 -- Don't ever try to invert a condition that is of the form of an
2667 -- AND or AND THEN (since we are not doing sufficiently general
2668 -- processing to allow this).
2670 if Sens
= False then
2676 -- Recursively process AND and AND THEN branches
2678 Process_Current_Value_Condition
(Left_Opnd
(Cond
), True);
2680 if Op
/= N_Empty
then
2684 Process_Current_Value_Condition
(Right_Opnd
(Cond
), True);
2687 -- Case of relational operator
2689 elsif Nkind
(Cond
) in N_Op_Compare
then
2692 -- Invert sense of test if inverted test
2694 if Sens
= False then
2696 when N_Op_Eq
=> Op
:= N_Op_Ne
;
2697 when N_Op_Ne
=> Op
:= N_Op_Eq
;
2698 when N_Op_Lt
=> Op
:= N_Op_Ge
;
2699 when N_Op_Gt
=> Op
:= N_Op_Le
;
2700 when N_Op_Le
=> Op
:= N_Op_Gt
;
2701 when N_Op_Ge
=> Op
:= N_Op_Lt
;
2702 when others => raise Program_Error
;
2706 -- Case of entity op value
2708 if Is_Entity_Name
(Left_Opnd
(Cond
))
2709 and then Ent
= Entity
(Left_Opnd
(Cond
))
2710 and then Compile_Time_Known_Value
(Right_Opnd
(Cond
))
2712 Val
:= Right_Opnd
(Cond
);
2714 -- Case of value op entity
2716 elsif Is_Entity_Name
(Right_Opnd
(Cond
))
2717 and then Ent
= Entity
(Right_Opnd
(Cond
))
2718 and then Compile_Time_Known_Value
(Left_Opnd
(Cond
))
2720 Val
:= Left_Opnd
(Cond
);
2722 -- We are effectively swapping operands
2725 when N_Op_Eq
=> null;
2726 when N_Op_Ne
=> null;
2727 when N_Op_Lt
=> Op
:= N_Op_Gt
;
2728 when N_Op_Gt
=> Op
:= N_Op_Lt
;
2729 when N_Op_Le
=> Op
:= N_Op_Ge
;
2730 when N_Op_Ge
=> Op
:= N_Op_Le
;
2731 when others => raise Program_Error
;
2740 -- Case of Boolean variable reference, return as though the
2741 -- reference had said var = True.
2744 if Is_Entity_Name
(Cond
) and then Ent
= Entity
(Cond
) then
2745 Val
:= New_Occurrence_Of
(Standard_True
, Sloc
(Cond
));
2747 if Sens
= False then
2754 end Process_Current_Value_Condition
;
2756 -- Start of processing for Get_Current_Value_Condition
2762 -- Immediate return, nothing doing, if this is not an object
2764 if Ekind
(Ent
) not in Object_Kind
then
2768 -- Otherwise examine current value
2771 CV
: constant Node_Id
:= Current_Value
(Ent
);
2776 -- If statement. Condition is known true in THEN section, known False
2777 -- in any ELSIF or ELSE part, and unknown outside the IF statement.
2779 if Nkind
(CV
) = N_If_Statement
then
2781 -- Before start of IF statement
2783 if Loc
< Sloc
(CV
) then
2786 -- After end of IF statement
2788 elsif Loc
>= Sloc
(CV
) + Text_Ptr
(UI_To_Int
(End_Span
(CV
))) then
2792 -- At this stage we know that we are within the IF statement, but
2793 -- unfortunately, the tree does not record the SLOC of the ELSE so
2794 -- we cannot use a simple SLOC comparison to distinguish between
2795 -- the then/else statements, so we have to climb the tree.
2802 while Parent
(N
) /= CV
loop
2805 -- If we fall off the top of the tree, then that's odd, but
2806 -- perhaps it could occur in some error situation, and the
2807 -- safest response is simply to assume that the outcome of
2808 -- the condition is unknown. No point in bombing during an
2809 -- attempt to optimize things.
2816 -- Now we have N pointing to a node whose parent is the IF
2817 -- statement in question, so now we can tell if we are within
2818 -- the THEN statements.
2820 if Is_List_Member
(N
)
2821 and then List_Containing
(N
) = Then_Statements
(CV
)
2825 -- If the variable reference does not come from source, we
2826 -- cannot reliably tell whether it appears in the else part.
2827 -- In particular, if it appears in generated code for a node
2828 -- that requires finalization, it may be attached to a list
2829 -- that has not been yet inserted into the code. For now,
2830 -- treat it as unknown.
2832 elsif not Comes_From_Source
(N
) then
2835 -- Otherwise we must be in ELSIF or ELSE part
2842 -- ELSIF part. Condition is known true within the referenced
2843 -- ELSIF, known False in any subsequent ELSIF or ELSE part,
2844 -- and unknown before the ELSE part or after the IF statement.
2846 elsif Nkind
(CV
) = N_Elsif_Part
then
2848 -- if the Elsif_Part had condition_actions, the elsif has been
2849 -- rewritten as a nested if, and the original elsif_part is
2850 -- detached from the tree, so there is no way to obtain useful
2851 -- information on the current value of the variable.
2852 -- Can this be improved ???
2854 if No
(Parent
(CV
)) then
2860 -- Before start of ELSIF part
2862 if Loc
< Sloc
(CV
) then
2865 -- After end of IF statement
2867 elsif Loc
>= Sloc
(Stm
) +
2868 Text_Ptr
(UI_To_Int
(End_Span
(Stm
)))
2873 -- Again we lack the SLOC of the ELSE, so we need to climb the
2874 -- tree to see if we are within the ELSIF part in question.
2881 while Parent
(N
) /= Stm
loop
2884 -- If we fall off the top of the tree, then that's odd, but
2885 -- perhaps it could occur in some error situation, and the
2886 -- safest response is simply to assume that the outcome of
2887 -- the condition is unknown. No point in bombing during an
2888 -- attempt to optimize things.
2895 -- Now we have N pointing to a node whose parent is the IF
2896 -- statement in question, so see if is the ELSIF part we want.
2897 -- the THEN statements.
2902 -- Otherwise we must be in subsequent ELSIF or ELSE part
2909 -- Iteration scheme of while loop. The condition is known to be
2910 -- true within the body of the loop.
2912 elsif Nkind
(CV
) = N_Iteration_Scheme
then
2914 Loop_Stmt
: constant Node_Id
:= Parent
(CV
);
2917 -- Before start of body of loop
2919 if Loc
< Sloc
(Loop_Stmt
) then
2922 -- After end of LOOP statement
2924 elsif Loc
>= Sloc
(End_Label
(Loop_Stmt
)) then
2927 -- We are within the body of the loop
2934 -- All other cases of Current_Value settings
2940 -- If we fall through here, then we have a reportable condition, Sens
2941 -- is True if the condition is true and False if it needs inverting.
2943 Process_Current_Value_Condition
(Condition
(CV
), Sens
);
2945 end Get_Current_Value_Condition
;
2947 ---------------------
2948 -- Get_Stream_Size --
2949 ---------------------
2951 function Get_Stream_Size
(E
: Entity_Id
) return Uint
is
2953 -- If we have a Stream_Size clause for this type use it
2955 if Has_Stream_Size_Clause
(E
) then
2956 return Static_Integer
(Expression
(Stream_Size_Clause
(E
)));
2958 -- Otherwise the Stream_Size if the size of the type
2963 end Get_Stream_Size
;
2965 ---------------------------
2966 -- Has_Access_Constraint --
2967 ---------------------------
2969 function Has_Access_Constraint
(E
: Entity_Id
) return Boolean is
2971 T
: constant Entity_Id
:= Etype
(E
);
2974 if Has_Per_Object_Constraint
(E
) and then Has_Discriminants
(T
) then
2975 Disc
:= First_Discriminant
(T
);
2976 while Present
(Disc
) loop
2977 if Is_Access_Type
(Etype
(Disc
)) then
2981 Next_Discriminant
(Disc
);
2988 end Has_Access_Constraint
;
2990 ----------------------------------
2991 -- Has_Following_Address_Clause --
2992 ----------------------------------
2994 -- Should this function check the private part in a package ???
2996 function Has_Following_Address_Clause
(D
: Node_Id
) return Boolean is
2997 Id
: constant Entity_Id
:= Defining_Identifier
(D
);
3002 while Present
(Decl
) loop
3003 if Nkind
(Decl
) = N_At_Clause
3004 and then Chars
(Identifier
(Decl
)) = Chars
(Id
)
3008 elsif Nkind
(Decl
) = N_Attribute_Definition_Clause
3009 and then Chars
(Decl
) = Name_Address
3010 and then Chars
(Name
(Decl
)) = Chars
(Id
)
3019 end Has_Following_Address_Clause
;
3021 --------------------
3022 -- Homonym_Number --
3023 --------------------
3025 function Homonym_Number
(Subp
: Entity_Id
) return Nat
is
3031 Hom
:= Homonym
(Subp
);
3032 while Present
(Hom
) loop
3033 if Scope
(Hom
) = Scope
(Subp
) then
3037 Hom
:= Homonym
(Hom
);
3043 -----------------------------------
3044 -- In_Library_Level_Package_Body --
3045 -----------------------------------
3047 function In_Library_Level_Package_Body
(Id
: Entity_Id
) return Boolean is
3049 -- First determine whether the entity appears at the library level, then
3050 -- look at the containing unit.
3052 if Is_Library_Level_Entity
(Id
) then
3054 Container
: constant Node_Id
:= Cunit
(Get_Source_Unit
(Id
));
3057 return Nkind
(Unit
(Container
)) = N_Package_Body
;
3062 end In_Library_Level_Package_Body
;
3064 ------------------------------
3065 -- In_Unconditional_Context --
3066 ------------------------------
3068 function In_Unconditional_Context
(Node
: Node_Id
) return Boolean is
3073 while Present
(P
) loop
3075 when N_Subprogram_Body
=>
3078 when N_If_Statement
=>
3081 when N_Loop_Statement
=>
3084 when N_Case_Statement
=>
3093 end In_Unconditional_Context
;
3099 procedure Insert_Action
(Assoc_Node
: Node_Id
; Ins_Action
: Node_Id
) is
3101 if Present
(Ins_Action
) then
3102 Insert_Actions
(Assoc_Node
, New_List
(Ins_Action
));
3106 -- Version with check(s) suppressed
3108 procedure Insert_Action
3109 (Assoc_Node
: Node_Id
; Ins_Action
: Node_Id
; Suppress
: Check_Id
)
3112 Insert_Actions
(Assoc_Node
, New_List
(Ins_Action
), Suppress
);
3115 -------------------------
3116 -- Insert_Action_After --
3117 -------------------------
3119 procedure Insert_Action_After
3120 (Assoc_Node
: Node_Id
;
3121 Ins_Action
: Node_Id
)
3124 Insert_Actions_After
(Assoc_Node
, New_List
(Ins_Action
));
3125 end Insert_Action_After
;
3127 --------------------
3128 -- Insert_Actions --
3129 --------------------
3131 procedure Insert_Actions
(Assoc_Node
: Node_Id
; Ins_Actions
: List_Id
) is
3135 Wrapped_Node
: Node_Id
:= Empty
;
3138 if No
(Ins_Actions
) or else Is_Empty_List
(Ins_Actions
) then
3142 -- Ignore insert of actions from inside default expression (or other
3143 -- similar "spec expression") in the special spec-expression analyze
3144 -- mode. Any insertions at this point have no relevance, since we are
3145 -- only doing the analyze to freeze the types of any static expressions.
3146 -- See section "Handling of Default Expressions" in the spec of package
3147 -- Sem for further details.
3149 if In_Spec_Expression
then
3153 -- If the action derives from stuff inside a record, then the actions
3154 -- are attached to the current scope, to be inserted and analyzed on
3155 -- exit from the scope. The reason for this is that we may also be
3156 -- generating freeze actions at the same time, and they must eventually
3157 -- be elaborated in the correct order.
3159 if Is_Record_Type
(Current_Scope
)
3160 and then not Is_Frozen
(Current_Scope
)
3162 if No
(Scope_Stack
.Table
3163 (Scope_Stack
.Last
).Pending_Freeze_Actions
)
3165 Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
:=
3170 Scope_Stack
.Table
(Scope_Stack
.Last
).Pending_Freeze_Actions
);
3176 -- We now intend to climb up the tree to find the right point to
3177 -- insert the actions. We start at Assoc_Node, unless this node is a
3178 -- subexpression in which case we start with its parent. We do this for
3179 -- two reasons. First it speeds things up. Second, if Assoc_Node is
3180 -- itself one of the special nodes like N_And_Then, then we assume that
3181 -- an initial request to insert actions for such a node does not expect
3182 -- the actions to get deposited in the node for later handling when the
3183 -- node is expanded, since clearly the node is being dealt with by the
3184 -- caller. Note that in the subexpression case, N is always the child we
3187 -- N_Raise_xxx_Error is an annoying special case, it is a statement if
3188 -- it has type Standard_Void_Type, and a subexpression otherwise.
3189 -- otherwise. Procedure calls, and similarly procedure attribute
3190 -- references, are also statements.
3192 if Nkind
(Assoc_Node
) in N_Subexpr
3193 and then (Nkind
(Assoc_Node
) not in N_Raise_xxx_Error
3194 or else Etype
(Assoc_Node
) /= Standard_Void_Type
)
3195 and then Nkind
(Assoc_Node
) /= N_Procedure_Call_Statement
3196 and then (Nkind
(Assoc_Node
) /= N_Attribute_Reference
3198 not Is_Procedure_Attribute_Name
3199 (Attribute_Name
(Assoc_Node
)))
3202 P
:= Parent
(Assoc_Node
);
3204 -- Non-subexpression case. Note that N is initially Empty in this case
3205 -- (N is only guaranteed Non-Empty in the subexpr case).
3212 -- Capture root of the transient scope
3214 if Scope_Is_Transient
then
3215 Wrapped_Node
:= Node_To_Be_Wrapped
;
3219 pragma Assert
(Present
(P
));
3221 -- Make sure that inserted actions stay in the transient scope
3223 if Present
(Wrapped_Node
) and then N
= Wrapped_Node
then
3224 Store_Before_Actions_In_Scope
(Ins_Actions
);
3230 -- Case of right operand of AND THEN or OR ELSE. Put the actions
3231 -- in the Actions field of the right operand. They will be moved
3232 -- out further when the AND THEN or OR ELSE operator is expanded.
3233 -- Nothing special needs to be done for the left operand since
3234 -- in that case the actions are executed unconditionally.
3236 when N_Short_Circuit
=>
3237 if N
= Right_Opnd
(P
) then
3239 -- We are now going to either append the actions to the
3240 -- actions field of the short-circuit operation. We will
3241 -- also analyze the actions now.
3243 -- This analysis is really too early, the proper thing would
3244 -- be to just park them there now, and only analyze them if
3245 -- we find we really need them, and to it at the proper
3246 -- final insertion point. However attempting to this proved
3247 -- tricky, so for now we just kill current values before and
3248 -- after the analyze call to make sure we avoid peculiar
3249 -- optimizations from this out of order insertion.
3251 Kill_Current_Values
;
3253 if Present
(Actions
(P
)) then
3254 Insert_List_After_And_Analyze
3255 (Last
(Actions
(P
)), Ins_Actions
);
3257 Set_Actions
(P
, Ins_Actions
);
3258 Analyze_List
(Actions
(P
));
3261 Kill_Current_Values
;
3266 -- Then or Else dependent expression of an if expression. Add
3267 -- actions to Then_Actions or Else_Actions field as appropriate.
3268 -- The actions will be moved further out when the if is expanded.
3270 when N_If_Expression
=>
3272 ThenX
: constant Node_Id
:= Next
(First
(Expressions
(P
)));
3273 ElseX
: constant Node_Id
:= Next
(ThenX
);
3276 -- If the enclosing expression is already analyzed, as
3277 -- is the case for nested elaboration checks, insert the
3278 -- conditional further out.
3280 if Analyzed
(P
) then
3283 -- Actions belong to the then expression, temporarily place
3284 -- them as Then_Actions of the if expression. They will be
3285 -- moved to the proper place later when the if expression
3288 elsif N
= ThenX
then
3289 if Present
(Then_Actions
(P
)) then
3290 Insert_List_After_And_Analyze
3291 (Last
(Then_Actions
(P
)), Ins_Actions
);
3293 Set_Then_Actions
(P
, Ins_Actions
);
3294 Analyze_List
(Then_Actions
(P
));
3299 -- Actions belong to the else expression, temporarily place
3300 -- them as Else_Actions of the if expression. They will be
3301 -- moved to the proper place later when the if expression
3304 elsif N
= ElseX
then
3305 if Present
(Else_Actions
(P
)) then
3306 Insert_List_After_And_Analyze
3307 (Last
(Else_Actions
(P
)), Ins_Actions
);
3309 Set_Else_Actions
(P
, Ins_Actions
);
3310 Analyze_List
(Else_Actions
(P
));
3315 -- Actions belong to the condition. In this case they are
3316 -- unconditionally executed, and so we can continue the
3317 -- search for the proper insert point.
3324 -- Alternative of case expression, we place the action in the
3325 -- Actions field of the case expression alternative, this will
3326 -- be handled when the case expression is expanded.
3328 when N_Case_Expression_Alternative
=>
3329 if Present
(Actions
(P
)) then
3330 Insert_List_After_And_Analyze
3331 (Last
(Actions
(P
)), Ins_Actions
);
3333 Set_Actions
(P
, Ins_Actions
);
3334 Analyze_List
(Actions
(P
));
3339 -- Case of appearing within an Expressions_With_Actions node. When
3340 -- the new actions come from the expression of the expression with
3341 -- actions, they must be added to the existing actions. The other
3342 -- alternative is when the new actions are related to one of the
3343 -- existing actions of the expression with actions. In that case
3344 -- they must be inserted further up the tree.
3346 when N_Expression_With_Actions
=>
3347 if N
= Expression
(P
) then
3348 Insert_List_After_And_Analyze
3349 (Last
(Actions
(P
)), Ins_Actions
);
3353 -- Case of appearing in the condition of a while expression or
3354 -- elsif. We insert the actions into the Condition_Actions field.
3355 -- They will be moved further out when the while loop or elsif
3358 when N_Iteration_Scheme |
3361 if N
= Condition
(P
) then
3362 if Present
(Condition_Actions
(P
)) then
3363 Insert_List_After_And_Analyze
3364 (Last
(Condition_Actions
(P
)), Ins_Actions
);
3366 Set_Condition_Actions
(P
, Ins_Actions
);
3368 -- Set the parent of the insert actions explicitly. This
3369 -- is not a syntactic field, but we need the parent field
3370 -- set, in particular so that freeze can understand that
3371 -- it is dealing with condition actions, and properly
3372 -- insert the freezing actions.
3374 Set_Parent
(Ins_Actions
, P
);
3375 Analyze_List
(Condition_Actions
(P
));
3381 -- Statements, declarations, pragmas, representation clauses
3386 N_Procedure_Call_Statement |
3387 N_Statement_Other_Than_Procedure_Call |
3393 -- Representation_Clause
3396 N_Attribute_Definition_Clause |
3397 N_Enumeration_Representation_Clause |
3398 N_Record_Representation_Clause |
3402 N_Abstract_Subprogram_Declaration |
3404 N_Exception_Declaration |
3405 N_Exception_Renaming_Declaration |
3406 N_Expression_Function |
3407 N_Formal_Abstract_Subprogram_Declaration |
3408 N_Formal_Concrete_Subprogram_Declaration |
3409 N_Formal_Object_Declaration |
3410 N_Formal_Type_Declaration |
3411 N_Full_Type_Declaration |
3412 N_Function_Instantiation |
3413 N_Generic_Function_Renaming_Declaration |
3414 N_Generic_Package_Declaration |
3415 N_Generic_Package_Renaming_Declaration |
3416 N_Generic_Procedure_Renaming_Declaration |
3417 N_Generic_Subprogram_Declaration |
3418 N_Implicit_Label_Declaration |
3419 N_Incomplete_Type_Declaration |
3420 N_Number_Declaration |
3421 N_Object_Declaration |
3422 N_Object_Renaming_Declaration |
3424 N_Package_Body_Stub |
3425 N_Package_Declaration |
3426 N_Package_Instantiation |
3427 N_Package_Renaming_Declaration |
3428 N_Private_Extension_Declaration |
3429 N_Private_Type_Declaration |
3430 N_Procedure_Instantiation |
3432 N_Protected_Body_Stub |
3433 N_Protected_Type_Declaration |
3434 N_Single_Task_Declaration |
3436 N_Subprogram_Body_Stub |
3437 N_Subprogram_Declaration |
3438 N_Subprogram_Renaming_Declaration |
3439 N_Subtype_Declaration |
3442 N_Task_Type_Declaration |
3444 -- Use clauses can appear in lists of declarations
3446 N_Use_Package_Clause |
3449 -- Freeze entity behaves like a declaration or statement
3453 -- Do not insert here if the item is not a list member (this
3454 -- happens for example with a triggering statement, and the
3455 -- proper approach is to insert before the entire select).
3457 if not Is_List_Member
(P
) then
3460 -- Do not insert if parent of P is an N_Component_Association
3461 -- node (i.e. we are in the context of an N_Aggregate or
3462 -- N_Extension_Aggregate node. In this case we want to insert
3463 -- before the entire aggregate.
3465 elsif Nkind
(Parent
(P
)) = N_Component_Association
then
3468 -- Do not insert if the parent of P is either an N_Variant node
3469 -- or an N_Record_Definition node, meaning in either case that
3470 -- P is a member of a component list, and that therefore the
3471 -- actions should be inserted outside the complete record
3474 elsif Nkind_In
(Parent
(P
), N_Variant
, N_Record_Definition
) then
3477 -- Do not insert freeze nodes within the loop generated for
3478 -- an aggregate, because they may be elaborated too late for
3479 -- subsequent use in the back end: within a package spec the
3480 -- loop is part of the elaboration procedure and is only
3481 -- elaborated during the second pass.
3483 -- If the loop comes from source, or the entity is local to the
3484 -- loop itself it must remain within.
3486 elsif Nkind
(Parent
(P
)) = N_Loop_Statement
3487 and then not Comes_From_Source
(Parent
(P
))
3488 and then Nkind
(First
(Ins_Actions
)) = N_Freeze_Entity
3490 Scope
(Entity
(First
(Ins_Actions
))) /= Current_Scope
3494 -- Otherwise we can go ahead and do the insertion
3496 elsif P
= Wrapped_Node
then
3497 Store_Before_Actions_In_Scope
(Ins_Actions
);
3501 Insert_List_Before_And_Analyze
(P
, Ins_Actions
);
3505 -- A special case, N_Raise_xxx_Error can act either as a statement
3506 -- or a subexpression. We tell the difference by looking at the
3507 -- Etype. It is set to Standard_Void_Type in the statement case.
3510 N_Raise_xxx_Error
=>
3511 if Etype
(P
) = Standard_Void_Type
then
3512 if P
= Wrapped_Node
then
3513 Store_Before_Actions_In_Scope
(Ins_Actions
);
3515 Insert_List_Before_And_Analyze
(P
, Ins_Actions
);
3520 -- In the subexpression case, keep climbing
3526 -- If a component association appears within a loop created for
3527 -- an array aggregate, attach the actions to the association so
3528 -- they can be subsequently inserted within the loop. For other
3529 -- component associations insert outside of the aggregate. For
3530 -- an association that will generate a loop, its Loop_Actions
3531 -- attribute is already initialized (see exp_aggr.adb).
3533 -- The list of loop_actions can in turn generate additional ones,
3534 -- that are inserted before the associated node. If the associated
3535 -- node is outside the aggregate, the new actions are collected
3536 -- at the end of the loop actions, to respect the order in which
3537 -- they are to be elaborated.
3540 N_Component_Association
=>
3541 if Nkind
(Parent
(P
)) = N_Aggregate
3542 and then Present
(Loop_Actions
(P
))
3544 if Is_Empty_List
(Loop_Actions
(P
)) then
3545 Set_Loop_Actions
(P
, Ins_Actions
);
3546 Analyze_List
(Ins_Actions
);
3553 -- Check whether these actions were generated by a
3554 -- declaration that is part of the loop_ actions
3555 -- for the component_association.
3558 while Present
(Decl
) loop
3559 exit when Parent
(Decl
) = P
3560 and then Is_List_Member
(Decl
)
3562 List_Containing
(Decl
) = Loop_Actions
(P
);
3563 Decl
:= Parent
(Decl
);
3566 if Present
(Decl
) then
3567 Insert_List_Before_And_Analyze
3568 (Decl
, Ins_Actions
);
3570 Insert_List_After_And_Analyze
3571 (Last
(Loop_Actions
(P
)), Ins_Actions
);
3582 -- Another special case, an attribute denoting a procedure call
3585 N_Attribute_Reference
=>
3586 if Is_Procedure_Attribute_Name
(Attribute_Name
(P
)) then
3587 if P
= Wrapped_Node
then
3588 Store_Before_Actions_In_Scope
(Ins_Actions
);
3590 Insert_List_Before_And_Analyze
(P
, Ins_Actions
);
3595 -- In the subexpression case, keep climbing
3601 -- A contract node should not belong to the tree
3604 raise Program_Error
;
3606 -- For all other node types, keep climbing tree
3610 N_Accept_Alternative |
3611 N_Access_Definition |
3612 N_Access_Function_Definition |
3613 N_Access_Procedure_Definition |
3614 N_Access_To_Object_Definition |
3617 N_Aspect_Specification |
3619 N_Case_Statement_Alternative |
3620 N_Character_Literal |
3621 N_Compilation_Unit |
3622 N_Compilation_Unit_Aux |
3623 N_Component_Clause |
3624 N_Component_Declaration |
3625 N_Component_Definition |
3627 N_Constrained_Array_Definition |
3628 N_Decimal_Fixed_Point_Definition |
3629 N_Defining_Character_Literal |
3630 N_Defining_Identifier |
3631 N_Defining_Operator_Symbol |
3632 N_Defining_Program_Unit_Name |
3633 N_Delay_Alternative |
3634 N_Delta_Constraint |
3635 N_Derived_Type_Definition |
3637 N_Digits_Constraint |
3638 N_Discriminant_Association |
3639 N_Discriminant_Specification |
3641 N_Entry_Body_Formal_Part |
3642 N_Entry_Call_Alternative |
3643 N_Entry_Declaration |
3644 N_Entry_Index_Specification |
3645 N_Enumeration_Type_Definition |
3647 N_Exception_Handler |
3649 N_Explicit_Dereference |
3650 N_Extension_Aggregate |
3651 N_Floating_Point_Definition |
3652 N_Formal_Decimal_Fixed_Point_Definition |
3653 N_Formal_Derived_Type_Definition |
3654 N_Formal_Discrete_Type_Definition |
3655 N_Formal_Floating_Point_Definition |
3656 N_Formal_Modular_Type_Definition |
3657 N_Formal_Ordinary_Fixed_Point_Definition |
3658 N_Formal_Package_Declaration |
3659 N_Formal_Private_Type_Definition |
3660 N_Formal_Incomplete_Type_Definition |
3661 N_Formal_Signed_Integer_Type_Definition |
3663 N_Function_Specification |
3664 N_Generic_Association |
3665 N_Handled_Sequence_Of_Statements |
3668 N_Index_Or_Discriminant_Constraint |
3669 N_Indexed_Component |
3671 N_Iterator_Specification |
3674 N_Loop_Parameter_Specification |
3676 N_Modular_Type_Definition |
3702 N_Op_Shift_Right_Arithmetic |
3706 N_Ordinary_Fixed_Point_Definition |
3708 N_Package_Specification |
3709 N_Parameter_Association |
3710 N_Parameter_Specification |
3711 N_Pop_Constraint_Error_Label |
3712 N_Pop_Program_Error_Label |
3713 N_Pop_Storage_Error_Label |
3714 N_Pragma_Argument_Association |
3715 N_Procedure_Specification |
3716 N_Protected_Definition |
3717 N_Push_Constraint_Error_Label |
3718 N_Push_Program_Error_Label |
3719 N_Push_Storage_Error_Label |
3720 N_Qualified_Expression |
3721 N_Quantified_Expression |
3722 N_Raise_Expression |
3724 N_Range_Constraint |
3726 N_Real_Range_Specification |
3727 N_Record_Definition |
3729 N_SCIL_Dispatch_Table_Tag_Init |
3730 N_SCIL_Dispatching_Call |
3731 N_SCIL_Membership_Test |
3732 N_Selected_Component |
3733 N_Signed_Integer_Type_Definition |
3734 N_Single_Protected_Declaration |
3738 N_Subtype_Indication |
3741 N_Terminate_Alternative |
3742 N_Triggering_Alternative |
3744 N_Unchecked_Expression |
3745 N_Unchecked_Type_Conversion |
3746 N_Unconstrained_Array_Definition |
3751 N_Validate_Unchecked_Conversion |
3758 -- If we fall through above tests, keep climbing tree
3762 if Nkind
(Parent
(N
)) = N_Subunit
then
3764 -- This is the proper body corresponding to a stub. Insertion must
3765 -- be done at the point of the stub, which is in the declarative
3766 -- part of the parent unit.
3768 P
:= Corresponding_Stub
(Parent
(N
));
3776 -- Version with check(s) suppressed
3778 procedure Insert_Actions
3779 (Assoc_Node
: Node_Id
;
3780 Ins_Actions
: List_Id
;
3781 Suppress
: Check_Id
)
3784 if Suppress
= All_Checks
then
3786 Sva
: constant Suppress_Array
:= Scope_Suppress
.Suppress
;
3788 Scope_Suppress
.Suppress
:= (others => True);
3789 Insert_Actions
(Assoc_Node
, Ins_Actions
);
3790 Scope_Suppress
.Suppress
:= Sva
;
3795 Svg
: constant Boolean := Scope_Suppress
.Suppress
(Suppress
);
3797 Scope_Suppress
.Suppress
(Suppress
) := True;
3798 Insert_Actions
(Assoc_Node
, Ins_Actions
);
3799 Scope_Suppress
.Suppress
(Suppress
) := Svg
;
3804 --------------------------
3805 -- Insert_Actions_After --
3806 --------------------------
3808 procedure Insert_Actions_After
3809 (Assoc_Node
: Node_Id
;
3810 Ins_Actions
: List_Id
)
3813 if Scope_Is_Transient
and then Assoc_Node
= Node_To_Be_Wrapped
then
3814 Store_After_Actions_In_Scope
(Ins_Actions
);
3816 Insert_List_After_And_Analyze
(Assoc_Node
, Ins_Actions
);
3818 end Insert_Actions_After
;
3820 ---------------------------------
3821 -- Insert_Library_Level_Action --
3822 ---------------------------------
3824 procedure Insert_Library_Level_Action
(N
: Node_Id
) is
3825 Aux
: constant Node_Id
:= Aux_Decls_Node
(Cunit
(Main_Unit
));
3828 Push_Scope
(Cunit_Entity
(Main_Unit
));
3829 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
3831 if No
(Actions
(Aux
)) then
3832 Set_Actions
(Aux
, New_List
(N
));
3834 Append
(N
, Actions
(Aux
));
3839 end Insert_Library_Level_Action
;
3841 ----------------------------------
3842 -- Insert_Library_Level_Actions --
3843 ----------------------------------
3845 procedure Insert_Library_Level_Actions
(L
: List_Id
) is
3846 Aux
: constant Node_Id
:= Aux_Decls_Node
(Cunit
(Main_Unit
));
3849 if Is_Non_Empty_List
(L
) then
3850 Push_Scope
(Cunit_Entity
(Main_Unit
));
3851 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
3853 if No
(Actions
(Aux
)) then
3854 Set_Actions
(Aux
, L
);
3857 Insert_List_After_And_Analyze
(Last
(Actions
(Aux
)), L
);
3862 end Insert_Library_Level_Actions
;
3864 ----------------------
3865 -- Inside_Init_Proc --
3866 ----------------------
3868 function Inside_Init_Proc
return Boolean is
3873 while Present
(S
) and then S
/= Standard_Standard
loop
3874 if Is_Init_Proc
(S
) then
3882 end Inside_Init_Proc
;
3884 ----------------------------
3885 -- Is_All_Null_Statements --
3886 ----------------------------
3888 function Is_All_Null_Statements
(L
: List_Id
) return Boolean is
3893 while Present
(Stm
) loop
3894 if Nkind
(Stm
) /= N_Null_Statement
then
3902 end Is_All_Null_Statements
;
3904 --------------------------------------------------
3905 -- Is_Displacement_Of_Object_Or_Function_Result --
3906 --------------------------------------------------
3908 function Is_Displacement_Of_Object_Or_Function_Result
3909 (Obj_Id
: Entity_Id
) return Boolean
3911 function Is_Controlled_Function_Call
(N
: Node_Id
) return Boolean;
3912 -- Determine if particular node denotes a controlled function call
3914 function Is_Displace_Call
(N
: Node_Id
) return Boolean;
3915 -- Determine whether a particular node is a call to Ada.Tags.Displace.
3916 -- The call might be nested within other actions such as conversions.
3918 function Is_Source_Object
(N
: Node_Id
) return Boolean;
3919 -- Determine whether a particular node denotes a source object
3921 ---------------------------------
3922 -- Is_Controlled_Function_Call --
3923 ---------------------------------
3925 function Is_Controlled_Function_Call
(N
: Node_Id
) return Boolean is
3926 Expr
: Node_Id
:= Original_Node
(N
);
3929 if Nkind
(Expr
) = N_Function_Call
then
3930 Expr
:= Name
(Expr
);
3933 -- The function call may appear in object.operation format
3935 if Nkind
(Expr
) = N_Selected_Component
then
3936 Expr
:= Selector_Name
(Expr
);
3940 Nkind_In
(Expr
, N_Expanded_Name
, N_Identifier
)
3941 and then Ekind
(Entity
(Expr
)) = E_Function
3942 and then Needs_Finalization
(Etype
(Entity
(Expr
)));
3943 end Is_Controlled_Function_Call
;
3945 ----------------------
3946 -- Is_Displace_Call --
3947 ----------------------
3949 function Is_Displace_Call
(N
: Node_Id
) return Boolean is
3950 Call
: Node_Id
:= N
;
3953 -- Strip various actions which may precede a call to Displace
3956 if Nkind
(Call
) = N_Explicit_Dereference
then
3957 Call
:= Prefix
(Call
);
3959 elsif Nkind_In
(Call
, N_Type_Conversion
,
3960 N_Unchecked_Type_Conversion
)
3962 Call
:= Expression
(Call
);
3971 and then Nkind
(Call
) = N_Function_Call
3972 and then Is_RTE
(Entity
(Name
(Call
)), RE_Displace
);
3973 end Is_Displace_Call
;
3975 ----------------------
3976 -- Is_Source_Object --
3977 ----------------------
3979 function Is_Source_Object
(N
: Node_Id
) return Boolean is
3983 and then Nkind
(N
) in N_Has_Entity
3984 and then Is_Object
(Entity
(N
))
3985 and then Comes_From_Source
(N
);
3986 end Is_Source_Object
;
3990 Decl
: constant Node_Id
:= Parent
(Obj_Id
);
3991 Obj_Typ
: constant Entity_Id
:= Base_Type
(Etype
(Obj_Id
));
3992 Orig_Decl
: constant Node_Id
:= Original_Node
(Decl
);
3994 -- Start of processing for Is_Displacement_Of_Object_Or_Function_Result
3999 -- Obj : CW_Type := Function_Call (...);
4003 -- Tmp : ... := Function_Call (...)'reference;
4004 -- Obj : CW_Type renames (... Ada.Tags.Displace (Tmp));
4006 -- where the return type of the function and the class-wide type require
4007 -- dispatch table pointer displacement.
4011 -- Obj : CW_Type := Src_Obj;
4015 -- Obj : CW_Type renames (... Ada.Tags.Displace (Src_Obj));
4017 -- where the type of the source object and the class-wide type require
4018 -- dispatch table pointer displacement.
4021 Nkind
(Decl
) = N_Object_Renaming_Declaration
4022 and then Nkind
(Orig_Decl
) = N_Object_Declaration
4023 and then Comes_From_Source
(Orig_Decl
)
4024 and then Is_Class_Wide_Type
(Obj_Typ
)
4025 and then Is_Displace_Call
(Renamed_Object
(Obj_Id
))
4027 (Is_Controlled_Function_Call
(Expression
(Orig_Decl
))
4028 or else Is_Source_Object
(Expression
(Orig_Decl
)));
4029 end Is_Displacement_Of_Object_Or_Function_Result
;
4031 ------------------------------
4032 -- Is_Finalizable_Transient --
4033 ------------------------------
4035 function Is_Finalizable_Transient
4037 Rel_Node
: Node_Id
) return Boolean
4039 Obj_Id
: constant Entity_Id
:= Defining_Identifier
(Decl
);
4040 Obj_Typ
: constant Entity_Id
:= Base_Type
(Etype
(Obj_Id
));
4041 Desig
: Entity_Id
:= Obj_Typ
;
4043 function Initialized_By_Access
(Trans_Id
: Entity_Id
) return Boolean;
4044 -- Determine whether transient object Trans_Id is initialized either
4045 -- by a function call which returns an access type or simply renames
4048 function Initialized_By_Aliased_BIP_Func_Call
4049 (Trans_Id
: Entity_Id
) return Boolean;
4050 -- Determine whether transient object Trans_Id is initialized by a
4051 -- build-in-place function call where the BIPalloc parameter is of
4052 -- value 1 and BIPaccess is not null. This case creates an aliasing
4053 -- between the returned value and the value denoted by BIPaccess.
4056 (Trans_Id
: Entity_Id
;
4057 First_Stmt
: Node_Id
) return Boolean;
4058 -- Determine whether transient object Trans_Id has been renamed or
4059 -- aliased through 'reference in the statement list starting from
4062 function Is_Allocated
(Trans_Id
: Entity_Id
) return Boolean;
4063 -- Determine whether transient object Trans_Id is allocated on the heap
4065 function Is_Iterated_Container
4066 (Trans_Id
: Entity_Id
;
4067 First_Stmt
: Node_Id
) return Boolean;
4068 -- Determine whether transient object Trans_Id denotes a container which
4069 -- is in the process of being iterated in the statement list starting
4072 ---------------------------
4073 -- Initialized_By_Access --
4074 ---------------------------
4076 function Initialized_By_Access
(Trans_Id
: Entity_Id
) return Boolean is
4077 Expr
: constant Node_Id
:= Expression
(Parent
(Trans_Id
));
4082 and then Nkind
(Expr
) /= N_Reference
4083 and then Is_Access_Type
(Etype
(Expr
));
4084 end Initialized_By_Access
;
4086 ------------------------------------------
4087 -- Initialized_By_Aliased_BIP_Func_Call --
4088 ------------------------------------------
4090 function Initialized_By_Aliased_BIP_Func_Call
4091 (Trans_Id
: Entity_Id
) return Boolean
4093 Call
: Node_Id
:= Expression
(Parent
(Trans_Id
));
4096 -- Build-in-place calls usually appear in 'reference format
4098 if Nkind
(Call
) = N_Reference
then
4099 Call
:= Prefix
(Call
);
4102 if Is_Build_In_Place_Function_Call
(Call
) then
4104 Access_Nam
: Name_Id
:= No_Name
;
4105 Access_OK
: Boolean := False;
4107 Alloc_Nam
: Name_Id
:= No_Name
;
4108 Alloc_OK
: Boolean := False;
4110 Func_Id
: Entity_Id
;
4114 -- Examine all parameter associations of the function call
4116 Param
:= First
(Parameter_Associations
(Call
));
4117 while Present
(Param
) loop
4118 if Nkind
(Param
) = N_Parameter_Association
4119 and then Nkind
(Selector_Name
(Param
)) = N_Identifier
4121 Actual
:= Explicit_Actual_Parameter
(Param
);
4122 Formal
:= Selector_Name
(Param
);
4124 -- Construct the names of formals BIPaccess and BIPalloc
4125 -- using the function name retrieved from an arbitrary
4128 if Access_Nam
= No_Name
4129 and then Alloc_Nam
= No_Name
4130 and then Present
(Entity
(Formal
))
4132 Func_Id
:= Scope
(Entity
(Formal
));
4135 New_External_Name
(Chars
(Func_Id
),
4136 BIP_Formal_Suffix
(BIP_Object_Access
));
4139 New_External_Name
(Chars
(Func_Id
),
4140 BIP_Formal_Suffix
(BIP_Alloc_Form
));
4143 -- A match for BIPaccess => Temp has been found
4145 if Chars
(Formal
) = Access_Nam
4146 and then Nkind
(Actual
) /= N_Null
4151 -- A match for BIPalloc => 1 has been found
4153 if Chars
(Formal
) = Alloc_Nam
4154 and then Nkind
(Actual
) = N_Integer_Literal
4155 and then Intval
(Actual
) = Uint_1
4164 return Access_OK
and Alloc_OK
;
4169 end Initialized_By_Aliased_BIP_Func_Call
;
4176 (Trans_Id
: Entity_Id
;
4177 First_Stmt
: Node_Id
) return Boolean
4179 function Find_Renamed_Object
(Ren_Decl
: Node_Id
) return Entity_Id
;
4180 -- Given an object renaming declaration, retrieve the entity of the
4181 -- renamed name. Return Empty if the renamed name is anything other
4182 -- than a variable or a constant.
4184 -------------------------
4185 -- Find_Renamed_Object --
4186 -------------------------
4188 function Find_Renamed_Object
(Ren_Decl
: Node_Id
) return Entity_Id
is
4189 Ren_Obj
: Node_Id
:= Empty
;
4191 function Find_Object
(N
: Node_Id
) return Traverse_Result
;
4192 -- Try to detect an object which is either a constant or a
4199 function Find_Object
(N
: Node_Id
) return Traverse_Result
is
4201 -- Stop the search once a constant or a variable has been
4204 if Nkind
(N
) = N_Identifier
4205 and then Present
(Entity
(N
))
4206 and then Ekind_In
(Entity
(N
), E_Constant
, E_Variable
)
4208 Ren_Obj
:= Entity
(N
);
4215 procedure Search
is new Traverse_Proc
(Find_Object
);
4219 Typ
: constant Entity_Id
:= Etype
(Defining_Identifier
(Ren_Decl
));
4221 -- Start of processing for Find_Renamed_Object
4224 -- Actions related to dispatching calls may appear as renamings of
4225 -- tags. Do not process this type of renaming because it does not
4226 -- use the actual value of the object.
4228 if not Is_RTE
(Typ
, RE_Tag_Ptr
) then
4229 Search
(Name
(Ren_Decl
));
4233 end Find_Renamed_Object
;
4238 Ren_Obj
: Entity_Id
;
4241 -- Start of processing for Is_Aliased
4245 while Present
(Stmt
) loop
4246 if Nkind
(Stmt
) = N_Object_Declaration
then
4247 Expr
:= Expression
(Stmt
);
4250 and then Nkind
(Expr
) = N_Reference
4251 and then Nkind
(Prefix
(Expr
)) = N_Identifier
4252 and then Entity
(Prefix
(Expr
)) = Trans_Id
4257 elsif Nkind
(Stmt
) = N_Object_Renaming_Declaration
then
4258 Ren_Obj
:= Find_Renamed_Object
(Stmt
);
4260 if Present
(Ren_Obj
) and then Ren_Obj
= Trans_Id
then
4275 function Is_Allocated
(Trans_Id
: Entity_Id
) return Boolean is
4276 Expr
: constant Node_Id
:= Expression
(Parent
(Trans_Id
));
4279 Is_Access_Type
(Etype
(Trans_Id
))
4280 and then Present
(Expr
)
4281 and then Nkind
(Expr
) = N_Allocator
;
4284 ---------------------------
4285 -- Is_Iterated_Container --
4286 ---------------------------
4288 function Is_Iterated_Container
4289 (Trans_Id
: Entity_Id
;
4290 First_Stmt
: Node_Id
) return Boolean
4300 -- It is not possible to iterate over containers in non-Ada 2012 code
4302 if Ada_Version
< Ada_2012
then
4306 Typ
:= Etype
(Trans_Id
);
4308 -- Handle access type created for secondary stack use
4310 if Is_Access_Type
(Typ
) then
4311 Typ
:= Designated_Type
(Typ
);
4314 -- Look for aspect Default_Iterator
4316 if Has_Aspects
(Parent
(Typ
)) then
4317 Aspect
:= Find_Value_Of_Aspect
(Typ
, Aspect_Default_Iterator
);
4319 if Present
(Aspect
) then
4320 Iter
:= Entity
(Aspect
);
4322 -- Examine the statements following the container object and
4323 -- look for a call to the default iterate routine where the
4324 -- first parameter is the transient. Such a call appears as:
4326 -- It : Access_To_CW_Iterator :=
4327 -- Iterate (Tran_Id.all, ...)'reference;
4330 while Present
(Stmt
) loop
4332 -- Detect an object declaration which is initialized by a
4333 -- secondary stack function call.
4335 if Nkind
(Stmt
) = N_Object_Declaration
4336 and then Present
(Expression
(Stmt
))
4337 and then Nkind
(Expression
(Stmt
)) = N_Reference
4338 and then Nkind
(Prefix
(Expression
(Stmt
))) =
4341 Call
:= Prefix
(Expression
(Stmt
));
4343 -- The call must invoke the default iterate routine of
4344 -- the container and the transient object must appear as
4345 -- the first actual parameter. Skip any calls whose names
4346 -- are not entities.
4348 if Is_Entity_Name
(Name
(Call
))
4349 and then Entity
(Name
(Call
)) = Iter
4350 and then Present
(Parameter_Associations
(Call
))
4352 Param
:= First
(Parameter_Associations
(Call
));
4354 if Nkind
(Param
) = N_Explicit_Dereference
4355 and then Entity
(Prefix
(Param
)) = Trans_Id
4368 end Is_Iterated_Container
;
4370 -- Start of processing for Is_Finalizable_Transient
4373 -- Handle access types
4375 if Is_Access_Type
(Desig
) then
4376 Desig
:= Available_View
(Designated_Type
(Desig
));
4380 Ekind_In
(Obj_Id
, E_Constant
, E_Variable
)
4381 and then Needs_Finalization
(Desig
)
4382 and then Requires_Transient_Scope
(Desig
)
4383 and then Nkind
(Rel_Node
) /= N_Simple_Return_Statement
4385 -- Do not consider renamed or 'reference-d transient objects because
4386 -- the act of renaming extends the object's lifetime.
4388 and then not Is_Aliased
(Obj_Id
, Decl
)
4390 -- Do not consider transient objects allocated on the heap since
4391 -- they are attached to a finalization master.
4393 and then not Is_Allocated
(Obj_Id
)
4395 -- If the transient object is a pointer, check that it is not
4396 -- initialized by a function which returns a pointer or acts as a
4397 -- renaming of another pointer.
4400 (not Is_Access_Type
(Obj_Typ
)
4401 or else not Initialized_By_Access
(Obj_Id
))
4403 -- Do not consider transient objects which act as indirect aliases
4404 -- of build-in-place function results.
4406 and then not Initialized_By_Aliased_BIP_Func_Call
(Obj_Id
)
4408 -- Do not consider conversions of tags to class-wide types
4410 and then not Is_Tag_To_Class_Wide_Conversion
(Obj_Id
)
4412 -- Do not consider containers in the context of iterator loops. Such
4413 -- transient objects must exist for as long as the loop is around,
4414 -- otherwise any operation carried out by the iterator will fail.
4416 and then not Is_Iterated_Container
(Obj_Id
, Decl
);
4417 end Is_Finalizable_Transient
;
4419 ---------------------------------
4420 -- Is_Fully_Repped_Tagged_Type --
4421 ---------------------------------
4423 function Is_Fully_Repped_Tagged_Type
(T
: Entity_Id
) return Boolean is
4424 U
: constant Entity_Id
:= Underlying_Type
(T
);
4428 if No
(U
) or else not Is_Tagged_Type
(U
) then
4430 elsif Has_Discriminants
(U
) then
4432 elsif not Has_Specified_Layout
(U
) then
4436 -- Here we have a tagged type, see if it has any unlayed out fields
4437 -- other than a possible tag and parent fields. If so, we return False.
4439 Comp
:= First_Component
(U
);
4440 while Present
(Comp
) loop
4441 if not Is_Tag
(Comp
)
4442 and then Chars
(Comp
) /= Name_uParent
4443 and then No
(Component_Clause
(Comp
))
4447 Next_Component
(Comp
);
4451 -- All components are layed out
4454 end Is_Fully_Repped_Tagged_Type
;
4456 ----------------------------------
4457 -- Is_Library_Level_Tagged_Type --
4458 ----------------------------------
4460 function Is_Library_Level_Tagged_Type
(Typ
: Entity_Id
) return Boolean is
4462 return Is_Tagged_Type
(Typ
) and then Is_Library_Level_Entity
(Typ
);
4463 end Is_Library_Level_Tagged_Type
;
4465 --------------------------
4466 -- Is_Non_BIP_Func_Call --
4467 --------------------------
4469 function Is_Non_BIP_Func_Call
(Expr
: Node_Id
) return Boolean is
4471 -- The expected call is of the format
4473 -- Func_Call'reference
4476 Nkind
(Expr
) = N_Reference
4477 and then Nkind
(Prefix
(Expr
)) = N_Function_Call
4478 and then not Is_Build_In_Place_Function_Call
(Prefix
(Expr
));
4479 end Is_Non_BIP_Func_Call
;
4481 ----------------------------------
4482 -- Is_Possibly_Unaligned_Object --
4483 ----------------------------------
4485 function Is_Possibly_Unaligned_Object
(N
: Node_Id
) return Boolean is
4486 T
: constant Entity_Id
:= Etype
(N
);
4489 -- If renamed object, apply test to underlying object
4491 if Is_Entity_Name
(N
)
4492 and then Is_Object
(Entity
(N
))
4493 and then Present
(Renamed_Object
(Entity
(N
)))
4495 return Is_Possibly_Unaligned_Object
(Renamed_Object
(Entity
(N
)));
4498 -- Tagged and controlled types and aliased types are always aligned, as
4499 -- are concurrent types.
4502 or else Has_Controlled_Component
(T
)
4503 or else Is_Concurrent_Type
(T
)
4504 or else Is_Tagged_Type
(T
)
4505 or else Is_Controlled
(T
)
4510 -- If this is an element of a packed array, may be unaligned
4512 if Is_Ref_To_Bit_Packed_Array
(N
) then
4516 -- Case of indexed component reference: test whether prefix is unaligned
4518 if Nkind
(N
) = N_Indexed_Component
then
4519 return Is_Possibly_Unaligned_Object
(Prefix
(N
));
4521 -- Case of selected component reference
4523 elsif Nkind
(N
) = N_Selected_Component
then
4525 P
: constant Node_Id
:= Prefix
(N
);
4526 C
: constant Entity_Id
:= Entity
(Selector_Name
(N
));
4531 -- If component reference is for an array with non-static bounds,
4532 -- then it is always aligned: we can only process unaligned arrays
4533 -- with static bounds (more precisely compile time known bounds).
4535 if Is_Array_Type
(T
)
4536 and then not Compile_Time_Known_Bounds
(T
)
4541 -- If component is aliased, it is definitely properly aligned
4543 if Is_Aliased
(C
) then
4547 -- If component is for a type implemented as a scalar, and the
4548 -- record is packed, and the component is other than the first
4549 -- component of the record, then the component may be unaligned.
4551 if Is_Packed
(Etype
(P
))
4552 and then Represented_As_Scalar
(Etype
(C
))
4553 and then First_Entity
(Scope
(C
)) /= C
4558 -- Compute maximum possible alignment for T
4560 -- If alignment is known, then that settles things
4562 if Known_Alignment
(T
) then
4563 M
:= UI_To_Int
(Alignment
(T
));
4565 -- If alignment is not known, tentatively set max alignment
4568 M
:= Ttypes
.Maximum_Alignment
;
4570 -- We can reduce this if the Esize is known since the default
4571 -- alignment will never be more than the smallest power of 2
4572 -- that does not exceed this Esize value.
4574 if Known_Esize
(T
) then
4575 S
:= UI_To_Int
(Esize
(T
));
4577 while (M
/ 2) >= S
loop
4583 -- The following code is historical, it used to be present but it
4584 -- is too cautious, because the front-end does not know the proper
4585 -- default alignments for the target. Also, if the alignment is
4586 -- not known, the front end can't know in any case! If a copy is
4587 -- needed, the back-end will take care of it. This whole section
4588 -- including this comment can be removed later ???
4590 -- If the component reference is for a record that has a specified
4591 -- alignment, and we either know it is too small, or cannot tell,
4592 -- then the component may be unaligned.
4594 -- What is the following commented out code ???
4596 -- if Known_Alignment (Etype (P))
4597 -- and then Alignment (Etype (P)) < Ttypes.Maximum_Alignment
4598 -- and then M > Alignment (Etype (P))
4603 -- Case of component clause present which may specify an
4604 -- unaligned position.
4606 if Present
(Component_Clause
(C
)) then
4608 -- Otherwise we can do a test to make sure that the actual
4609 -- start position in the record, and the length, are both
4610 -- consistent with the required alignment. If not, we know
4611 -- that we are unaligned.
4614 Align_In_Bits
: constant Nat
:= M
* System_Storage_Unit
;
4616 if Component_Bit_Offset
(C
) mod Align_In_Bits
/= 0
4617 or else Esize
(C
) mod Align_In_Bits
/= 0
4624 -- Otherwise, for a component reference, test prefix
4626 return Is_Possibly_Unaligned_Object
(P
);
4629 -- If not a component reference, must be aligned
4634 end Is_Possibly_Unaligned_Object
;
4636 ---------------------------------
4637 -- Is_Possibly_Unaligned_Slice --
4638 ---------------------------------
4640 function Is_Possibly_Unaligned_Slice
(N
: Node_Id
) return Boolean is
4642 -- Go to renamed object
4644 if Is_Entity_Name
(N
)
4645 and then Is_Object
(Entity
(N
))
4646 and then Present
(Renamed_Object
(Entity
(N
)))
4648 return Is_Possibly_Unaligned_Slice
(Renamed_Object
(Entity
(N
)));
4651 -- The reference must be a slice
4653 if Nkind
(N
) /= N_Slice
then
4657 -- Always assume the worst for a nested record component with a
4658 -- component clause, which gigi/gcc does not appear to handle well.
4659 -- It is not clear why this special test is needed at all ???
4661 if Nkind
(Prefix
(N
)) = N_Selected_Component
4662 and then Nkind
(Prefix
(Prefix
(N
))) = N_Selected_Component
4664 Present
(Component_Clause
(Entity
(Selector_Name
(Prefix
(N
)))))
4669 -- We only need to worry if the target has strict alignment
4671 if not Target_Strict_Alignment
then
4675 -- If it is a slice, then look at the array type being sliced
4678 Sarr
: constant Node_Id
:= Prefix
(N
);
4679 -- Prefix of the slice, i.e. the array being sliced
4681 Styp
: constant Entity_Id
:= Etype
(Prefix
(N
));
4682 -- Type of the array being sliced
4688 -- The problems arise if the array object that is being sliced
4689 -- is a component of a record or array, and we cannot guarantee
4690 -- the alignment of the array within its containing object.
4692 -- To investigate this, we look at successive prefixes to see
4693 -- if we have a worrisome indexed or selected component.
4697 -- Case of array is part of an indexed component reference
4699 if Nkind
(Pref
) = N_Indexed_Component
then
4700 Ptyp
:= Etype
(Prefix
(Pref
));
4702 -- The only problematic case is when the array is packed, in
4703 -- which case we really know nothing about the alignment of
4704 -- individual components.
4706 if Is_Bit_Packed_Array
(Ptyp
) then
4710 -- Case of array is part of a selected component reference
4712 elsif Nkind
(Pref
) = N_Selected_Component
then
4713 Ptyp
:= Etype
(Prefix
(Pref
));
4715 -- We are definitely in trouble if the record in question
4716 -- has an alignment, and either we know this alignment is
4717 -- inconsistent with the alignment of the slice, or we don't
4718 -- know what the alignment of the slice should be.
4720 if Known_Alignment
(Ptyp
)
4721 and then (Unknown_Alignment
(Styp
)
4722 or else Alignment
(Styp
) > Alignment
(Ptyp
))
4727 -- We are in potential trouble if the record type is packed.
4728 -- We could special case when we know that the array is the
4729 -- first component, but that's not such a simple case ???
4731 if Is_Packed
(Ptyp
) then
4735 -- We are in trouble if there is a component clause, and
4736 -- either we do not know the alignment of the slice, or
4737 -- the alignment of the slice is inconsistent with the
4738 -- bit position specified by the component clause.
4741 Field
: constant Entity_Id
:= Entity
(Selector_Name
(Pref
));
4743 if Present
(Component_Clause
(Field
))
4745 (Unknown_Alignment
(Styp
)
4747 (Component_Bit_Offset
(Field
) mod
4748 (System_Storage_Unit
* Alignment
(Styp
))) /= 0)
4754 -- For cases other than selected or indexed components we know we
4755 -- are OK, since no issues arise over alignment.
4761 -- We processed an indexed component or selected component
4762 -- reference that looked safe, so keep checking prefixes.
4764 Pref
:= Prefix
(Pref
);
4767 end Is_Possibly_Unaligned_Slice
;
4769 -------------------------------
4770 -- Is_Related_To_Func_Return --
4771 -------------------------------
4773 function Is_Related_To_Func_Return
(Id
: Entity_Id
) return Boolean is
4774 Expr
: constant Node_Id
:= Related_Expression
(Id
);
4778 and then Nkind
(Expr
) = N_Explicit_Dereference
4779 and then Nkind
(Parent
(Expr
)) = N_Simple_Return_Statement
;
4780 end Is_Related_To_Func_Return
;
4782 --------------------------------
4783 -- Is_Ref_To_Bit_Packed_Array --
4784 --------------------------------
4786 function Is_Ref_To_Bit_Packed_Array
(N
: Node_Id
) return Boolean is
4791 if Is_Entity_Name
(N
)
4792 and then Is_Object
(Entity
(N
))
4793 and then Present
(Renamed_Object
(Entity
(N
)))
4795 return Is_Ref_To_Bit_Packed_Array
(Renamed_Object
(Entity
(N
)));
4798 if Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
4799 if Is_Bit_Packed_Array
(Etype
(Prefix
(N
))) then
4802 Result
:= Is_Ref_To_Bit_Packed_Array
(Prefix
(N
));
4805 if Result
and then Nkind
(N
) = N_Indexed_Component
then
4806 Expr
:= First
(Expressions
(N
));
4807 while Present
(Expr
) loop
4808 Force_Evaluation
(Expr
);
4818 end Is_Ref_To_Bit_Packed_Array
;
4820 --------------------------------
4821 -- Is_Ref_To_Bit_Packed_Slice --
4822 --------------------------------
4824 function Is_Ref_To_Bit_Packed_Slice
(N
: Node_Id
) return Boolean is
4826 if Nkind
(N
) = N_Type_Conversion
then
4827 return Is_Ref_To_Bit_Packed_Slice
(Expression
(N
));
4829 elsif Is_Entity_Name
(N
)
4830 and then Is_Object
(Entity
(N
))
4831 and then Present
(Renamed_Object
(Entity
(N
)))
4833 return Is_Ref_To_Bit_Packed_Slice
(Renamed_Object
(Entity
(N
)));
4835 elsif Nkind
(N
) = N_Slice
4836 and then Is_Bit_Packed_Array
(Etype
(Prefix
(N
)))
4840 elsif Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
4841 return Is_Ref_To_Bit_Packed_Slice
(Prefix
(N
));
4846 end Is_Ref_To_Bit_Packed_Slice
;
4848 -----------------------
4849 -- Is_Renamed_Object --
4850 -----------------------
4852 function Is_Renamed_Object
(N
: Node_Id
) return Boolean is
4853 Pnod
: constant Node_Id
:= Parent
(N
);
4854 Kind
: constant Node_Kind
:= Nkind
(Pnod
);
4856 if Kind
= N_Object_Renaming_Declaration
then
4858 elsif Nkind_In
(Kind
, N_Indexed_Component
, N_Selected_Component
) then
4859 return Is_Renamed_Object
(Pnod
);
4863 end Is_Renamed_Object
;
4865 --------------------------------------
4866 -- Is_Secondary_Stack_BIP_Func_Call --
4867 --------------------------------------
4869 function Is_Secondary_Stack_BIP_Func_Call
(Expr
: Node_Id
) return Boolean is
4870 Call
: Node_Id
:= Expr
;
4873 -- Build-in-place calls usually appear in 'reference format. Note that
4874 -- the accessibility check machinery may add an extra 'reference due to
4875 -- side effect removal.
4877 while Nkind
(Call
) = N_Reference
loop
4878 Call
:= Prefix
(Call
);
4881 if Nkind_In
(Call
, N_Qualified_Expression
,
4882 N_Unchecked_Type_Conversion
)
4884 Call
:= Expression
(Call
);
4887 if Is_Build_In_Place_Function_Call
(Call
) then
4889 Access_Nam
: Name_Id
:= No_Name
;
4895 -- Examine all parameter associations of the function call
4897 Param
:= First
(Parameter_Associations
(Call
));
4898 while Present
(Param
) loop
4899 if Nkind
(Param
) = N_Parameter_Association
4900 and then Nkind
(Selector_Name
(Param
)) = N_Identifier
4902 Formal
:= Selector_Name
(Param
);
4903 Actual
:= Explicit_Actual_Parameter
(Param
);
4905 -- Construct the name of formal BIPalloc. It is much easier
4906 -- to extract the name of the function using an arbitrary
4907 -- formal's scope rather than the Name field of Call.
4909 if Access_Nam
= No_Name
4910 and then Present
(Entity
(Formal
))
4914 (Chars
(Scope
(Entity
(Formal
))),
4915 BIP_Formal_Suffix
(BIP_Alloc_Form
));
4918 -- A match for BIPalloc => 2 has been found
4920 if Chars
(Formal
) = Access_Nam
4921 and then Nkind
(Actual
) = N_Integer_Literal
4922 and then Intval
(Actual
) = Uint_2
4934 end Is_Secondary_Stack_BIP_Func_Call
;
4936 -------------------------------------
4937 -- Is_Tag_To_Class_Wide_Conversion --
4938 -------------------------------------
4940 function Is_Tag_To_Class_Wide_Conversion
4941 (Obj_Id
: Entity_Id
) return Boolean
4943 Expr
: constant Node_Id
:= Expression
(Parent
(Obj_Id
));
4947 Is_Class_Wide_Type
(Etype
(Obj_Id
))
4948 and then Present
(Expr
)
4949 and then Nkind
(Expr
) = N_Unchecked_Type_Conversion
4950 and then Etype
(Expression
(Expr
)) = RTE
(RE_Tag
);
4951 end Is_Tag_To_Class_Wide_Conversion
;
4953 ----------------------------
4954 -- Is_Untagged_Derivation --
4955 ----------------------------
4957 function Is_Untagged_Derivation
(T
: Entity_Id
) return Boolean is
4959 return (not Is_Tagged_Type
(T
) and then Is_Derived_Type
(T
))
4961 (Is_Private_Type
(T
) and then Present
(Full_View
(T
))
4962 and then not Is_Tagged_Type
(Full_View
(T
))
4963 and then Is_Derived_Type
(Full_View
(T
))
4964 and then Etype
(Full_View
(T
)) /= T
);
4965 end Is_Untagged_Derivation
;
4967 ---------------------------
4968 -- Is_Volatile_Reference --
4969 ---------------------------
4971 function Is_Volatile_Reference
(N
: Node_Id
) return Boolean is
4973 if Nkind
(N
) in N_Has_Etype
4974 and then Present
(Etype
(N
))
4975 and then Treat_As_Volatile
(Etype
(N
))
4979 elsif Is_Entity_Name
(N
) then
4980 return Treat_As_Volatile
(Entity
(N
));
4982 elsif Nkind
(N
) = N_Slice
then
4983 return Is_Volatile_Reference
(Prefix
(N
));
4985 elsif Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
4986 if (Is_Entity_Name
(Prefix
(N
))
4987 and then Has_Volatile_Components
(Entity
(Prefix
(N
))))
4988 or else (Present
(Etype
(Prefix
(N
)))
4989 and then Has_Volatile_Components
(Etype
(Prefix
(N
))))
4993 return Is_Volatile_Reference
(Prefix
(N
));
4999 end Is_Volatile_Reference
;
5001 --------------------------
5002 -- Is_VM_By_Copy_Actual --
5003 --------------------------
5005 function Is_VM_By_Copy_Actual
(N
: Node_Id
) return Boolean is
5007 return VM_Target
/= No_VM
5008 and then (Nkind
(N
) = N_Slice
5010 (Nkind
(N
) = N_Identifier
5011 and then Present
(Renamed_Object
(Entity
(N
)))
5012 and then Nkind
(Renamed_Object
(Entity
(N
))) =
5014 end Is_VM_By_Copy_Actual
;
5016 --------------------
5017 -- Kill_Dead_Code --
5018 --------------------
5020 procedure Kill_Dead_Code
(N
: Node_Id
; Warn
: Boolean := False) is
5021 W
: Boolean := Warn
;
5022 -- Set False if warnings suppressed
5026 Remove_Warning_Messages
(N
);
5028 -- Generate warning if appropriate
5032 -- We suppress the warning if this code is under control of an
5033 -- if statement, whose condition is a simple identifier, and
5034 -- either we are in an instance, or warnings off is set for this
5035 -- identifier. The reason for killing it in the instance case is
5036 -- that it is common and reasonable for code to be deleted in
5037 -- instances for various reasons.
5039 if Nkind
(Parent
(N
)) = N_If_Statement
then
5041 C
: constant Node_Id
:= Condition
(Parent
(N
));
5043 if Nkind
(C
) = N_Identifier
5046 or else (Present
(Entity
(C
))
5047 and then Has_Warnings_Off
(Entity
(C
))))
5054 -- Generate warning if not suppressed
5058 ("?t?this code can never be executed and has been deleted!",
5063 -- Recurse into block statements and bodies to process declarations
5066 if Nkind
(N
) = N_Block_Statement
5067 or else Nkind
(N
) = N_Subprogram_Body
5068 or else Nkind
(N
) = N_Package_Body
5070 Kill_Dead_Code
(Declarations
(N
), False);
5071 Kill_Dead_Code
(Statements
(Handled_Statement_Sequence
(N
)));
5073 if Nkind
(N
) = N_Subprogram_Body
then
5074 Set_Is_Eliminated
(Defining_Entity
(N
));
5077 elsif Nkind
(N
) = N_Package_Declaration
then
5078 Kill_Dead_Code
(Visible_Declarations
(Specification
(N
)));
5079 Kill_Dead_Code
(Private_Declarations
(Specification
(N
)));
5081 -- ??? After this point, Delete_Tree has been called on all
5082 -- declarations in Specification (N), so references to entities
5083 -- therein look suspicious.
5086 E
: Entity_Id
:= First_Entity
(Defining_Entity
(N
));
5088 while Present
(E
) loop
5089 if Ekind
(E
) = E_Operator
then
5090 Set_Is_Eliminated
(E
);
5097 -- Recurse into composite statement to kill individual statements in
5098 -- particular instantiations.
5100 elsif Nkind
(N
) = N_If_Statement
then
5101 Kill_Dead_Code
(Then_Statements
(N
));
5102 Kill_Dead_Code
(Elsif_Parts
(N
));
5103 Kill_Dead_Code
(Else_Statements
(N
));
5105 elsif Nkind
(N
) = N_Loop_Statement
then
5106 Kill_Dead_Code
(Statements
(N
));
5108 elsif Nkind
(N
) = N_Case_Statement
then
5112 Alt
:= First
(Alternatives
(N
));
5113 while Present
(Alt
) loop
5114 Kill_Dead_Code
(Statements
(Alt
));
5119 elsif Nkind
(N
) = N_Case_Statement_Alternative
then
5120 Kill_Dead_Code
(Statements
(N
));
5122 -- Deal with dead instances caused by deleting instantiations
5124 elsif Nkind
(N
) in N_Generic_Instantiation
then
5125 Remove_Dead_Instance
(N
);
5130 -- Case where argument is a list of nodes to be killed
5132 procedure Kill_Dead_Code
(L
: List_Id
; Warn
: Boolean := False) is
5137 if Is_Non_Empty_List
(L
) then
5139 while Present
(N
) loop
5140 Kill_Dead_Code
(N
, W
);
5147 ------------------------
5148 -- Known_Non_Negative --
5149 ------------------------
5151 function Known_Non_Negative
(Opnd
: Node_Id
) return Boolean is
5153 if Is_OK_Static_Expression
(Opnd
) and then Expr_Value
(Opnd
) >= 0 then
5158 Lo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Opnd
));
5161 Is_OK_Static_Expression
(Lo
) and then Expr_Value
(Lo
) >= 0;
5164 end Known_Non_Negative
;
5166 --------------------
5167 -- Known_Non_Null --
5168 --------------------
5170 function Known_Non_Null
(N
: Node_Id
) return Boolean is
5172 -- Checks for case where N is an entity reference
5174 if Is_Entity_Name
(N
) and then Present
(Entity
(N
)) then
5176 E
: constant Entity_Id
:= Entity
(N
);
5181 -- First check if we are in decisive conditional
5183 Get_Current_Value_Condition
(N
, Op
, Val
);
5185 if Known_Null
(Val
) then
5186 if Op
= N_Op_Eq
then
5188 elsif Op
= N_Op_Ne
then
5193 -- If OK to do replacement, test Is_Known_Non_Null flag
5195 if OK_To_Do_Constant_Replacement
(E
) then
5196 return Is_Known_Non_Null
(E
);
5198 -- Otherwise if not safe to do replacement, then say so
5205 -- True if access attribute
5207 elsif Nkind
(N
) = N_Attribute_Reference
5208 and then Nam_In
(Attribute_Name
(N
), Name_Access
,
5209 Name_Unchecked_Access
,
5210 Name_Unrestricted_Access
)
5214 -- True if allocator
5216 elsif Nkind
(N
) = N_Allocator
then
5219 -- For a conversion, true if expression is known non-null
5221 elsif Nkind
(N
) = N_Type_Conversion
then
5222 return Known_Non_Null
(Expression
(N
));
5224 -- Above are all cases where the value could be determined to be
5225 -- non-null. In all other cases, we don't know, so return False.
5236 function Known_Null
(N
: Node_Id
) return Boolean is
5238 -- Checks for case where N is an entity reference
5240 if Is_Entity_Name
(N
) and then Present
(Entity
(N
)) then
5242 E
: constant Entity_Id
:= Entity
(N
);
5247 -- Constant null value is for sure null
5249 if Ekind
(E
) = E_Constant
5250 and then Known_Null
(Constant_Value
(E
))
5255 -- First check if we are in decisive conditional
5257 Get_Current_Value_Condition
(N
, Op
, Val
);
5259 if Known_Null
(Val
) then
5260 if Op
= N_Op_Eq
then
5262 elsif Op
= N_Op_Ne
then
5267 -- If OK to do replacement, test Is_Known_Null flag
5269 if OK_To_Do_Constant_Replacement
(E
) then
5270 return Is_Known_Null
(E
);
5272 -- Otherwise if not safe to do replacement, then say so
5279 -- True if explicit reference to null
5281 elsif Nkind
(N
) = N_Null
then
5284 -- For a conversion, true if expression is known null
5286 elsif Nkind
(N
) = N_Type_Conversion
then
5287 return Known_Null
(Expression
(N
));
5289 -- Above are all cases where the value could be determined to be null.
5290 -- In all other cases, we don't know, so return False.
5297 -----------------------------
5298 -- Make_CW_Equivalent_Type --
5299 -----------------------------
5301 -- Create a record type used as an equivalent of any member of the class
5302 -- which takes its size from exp.
5304 -- Generate the following code:
5306 -- type Equiv_T is record
5307 -- _parent : T (List of discriminant constraints taken from Exp);
5308 -- Ext__50 : Storage_Array (1 .. (Exp'size - Typ'object_size)/8);
5311 -- ??? Note that this type does not guarantee same alignment as all
5314 function Make_CW_Equivalent_Type
5316 E
: Node_Id
) return Entity_Id
5318 Loc
: constant Source_Ptr
:= Sloc
(E
);
5319 Root_Typ
: constant Entity_Id
:= Root_Type
(T
);
5320 List_Def
: constant List_Id
:= Empty_List
;
5321 Comp_List
: constant List_Id
:= New_List
;
5322 Equiv_Type
: Entity_Id
;
5323 Range_Type
: Entity_Id
;
5324 Str_Type
: Entity_Id
;
5325 Constr_Root
: Entity_Id
;
5329 -- If the root type is already constrained, there are no discriminants
5330 -- in the expression.
5332 if not Has_Discriminants
(Root_Typ
)
5333 or else Is_Constrained
(Root_Typ
)
5335 Constr_Root
:= Root_Typ
;
5337 Constr_Root
:= Make_Temporary
(Loc
, 'R');
5339 -- subtype cstr__n is T (List of discr constraints taken from Exp)
5341 Append_To
(List_Def
,
5342 Make_Subtype_Declaration
(Loc
,
5343 Defining_Identifier
=> Constr_Root
,
5344 Subtype_Indication
=> Make_Subtype_From_Expr
(E
, Root_Typ
)));
5347 -- Generate the range subtype declaration
5349 Range_Type
:= Make_Temporary
(Loc
, 'G');
5351 if not Is_Interface
(Root_Typ
) then
5353 -- subtype rg__xx is
5354 -- Storage_Offset range 1 .. (Expr'size - typ'size) / Storage_Unit
5357 Make_Op_Subtract
(Loc
,
5359 Make_Attribute_Reference
(Loc
,
5361 OK_Convert_To
(T
, Duplicate_Subexpr_No_Checks
(E
)),
5362 Attribute_Name
=> Name_Size
),
5364 Make_Attribute_Reference
(Loc
,
5365 Prefix
=> New_Reference_To
(Constr_Root
, Loc
),
5366 Attribute_Name
=> Name_Object_Size
));
5368 -- subtype rg__xx is
5369 -- Storage_Offset range 1 .. Expr'size / Storage_Unit
5372 Make_Attribute_Reference
(Loc
,
5374 OK_Convert_To
(T
, Duplicate_Subexpr_No_Checks
(E
)),
5375 Attribute_Name
=> Name_Size
);
5378 Set_Paren_Count
(Sizexpr
, 1);
5380 Append_To
(List_Def
,
5381 Make_Subtype_Declaration
(Loc
,
5382 Defining_Identifier
=> Range_Type
,
5383 Subtype_Indication
=>
5384 Make_Subtype_Indication
(Loc
,
5385 Subtype_Mark
=> New_Reference_To
(RTE
(RE_Storage_Offset
), Loc
),
5386 Constraint
=> Make_Range_Constraint
(Loc
,
5389 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
5391 Make_Op_Divide
(Loc
,
5392 Left_Opnd
=> Sizexpr
,
5393 Right_Opnd
=> Make_Integer_Literal
(Loc
,
5394 Intval
=> System_Storage_Unit
)))))));
5396 -- subtype str__nn is Storage_Array (rg__x);
5398 Str_Type
:= Make_Temporary
(Loc
, 'S');
5399 Append_To
(List_Def
,
5400 Make_Subtype_Declaration
(Loc
,
5401 Defining_Identifier
=> Str_Type
,
5402 Subtype_Indication
=>
5403 Make_Subtype_Indication
(Loc
,
5404 Subtype_Mark
=> New_Reference_To
(RTE
(RE_Storage_Array
), Loc
),
5406 Make_Index_Or_Discriminant_Constraint
(Loc
,
5408 New_List
(New_Reference_To
(Range_Type
, Loc
))))));
5410 -- type Equiv_T is record
5411 -- [ _parent : Tnn; ]
5415 Equiv_Type
:= Make_Temporary
(Loc
, 'T');
5416 Set_Ekind
(Equiv_Type
, E_Record_Type
);
5417 Set_Parent_Subtype
(Equiv_Type
, Constr_Root
);
5419 -- Set Is_Class_Wide_Equivalent_Type very early to trigger the special
5420 -- treatment for this type. In particular, even though _parent's type
5421 -- is a controlled type or contains controlled components, we do not
5422 -- want to set Has_Controlled_Component on it to avoid making it gain
5423 -- an unwanted _controller component.
5425 Set_Is_Class_Wide_Equivalent_Type
(Equiv_Type
);
5427 if not Is_Interface
(Root_Typ
) then
5428 Append_To
(Comp_List
,
5429 Make_Component_Declaration
(Loc
,
5430 Defining_Identifier
=>
5431 Make_Defining_Identifier
(Loc
, Name_uParent
),
5432 Component_Definition
=>
5433 Make_Component_Definition
(Loc
,
5434 Aliased_Present
=> False,
5435 Subtype_Indication
=> New_Reference_To
(Constr_Root
, Loc
))));
5438 Append_To
(Comp_List
,
5439 Make_Component_Declaration
(Loc
,
5440 Defining_Identifier
=> Make_Temporary
(Loc
, 'C'),
5441 Component_Definition
=>
5442 Make_Component_Definition
(Loc
,
5443 Aliased_Present
=> False,
5444 Subtype_Indication
=> New_Reference_To
(Str_Type
, Loc
))));
5446 Append_To
(List_Def
,
5447 Make_Full_Type_Declaration
(Loc
,
5448 Defining_Identifier
=> Equiv_Type
,
5450 Make_Record_Definition
(Loc
,
5452 Make_Component_List
(Loc
,
5453 Component_Items
=> Comp_List
,
5454 Variant_Part
=> Empty
))));
5456 -- Suppress all checks during the analysis of the expanded code to avoid
5457 -- the generation of spurious warnings under ZFP run-time.
5459 Insert_Actions
(E
, List_Def
, Suppress
=> All_Checks
);
5461 end Make_CW_Equivalent_Type
;
5463 -------------------------
5464 -- Make_Invariant_Call --
5465 -------------------------
5467 function Make_Invariant_Call
(Expr
: Node_Id
) return Node_Id
is
5468 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
5472 Typ
:= Etype
(Expr
);
5474 -- Subtypes may be subject to invariants coming from their respective
5477 if Ekind_In
(Typ
, E_Array_Subtype
,
5481 Typ
:= Base_Type
(Typ
);
5485 (Has_Invariants
(Typ
) and then Present
(Invariant_Procedure
(Typ
)));
5488 Make_Procedure_Call_Statement
(Loc
,
5490 New_Occurrence_Of
(Invariant_Procedure
(Typ
), Loc
),
5491 Parameter_Associations
=> New_List
(Relocate_Node
(Expr
)));
5492 end Make_Invariant_Call
;
5494 ------------------------
5495 -- Make_Literal_Range --
5496 ------------------------
5498 function Make_Literal_Range
5500 Literal_Typ
: Entity_Id
) return Node_Id
5502 Lo
: constant Node_Id
:=
5503 New_Copy_Tree
(String_Literal_Low_Bound
(Literal_Typ
));
5504 Index
: constant Entity_Id
:= Etype
(Lo
);
5507 Length_Expr
: constant Node_Id
:=
5508 Make_Op_Subtract
(Loc
,
5510 Make_Integer_Literal
(Loc
,
5511 Intval
=> String_Literal_Length
(Literal_Typ
)),
5513 Make_Integer_Literal
(Loc
, 1));
5516 Set_Analyzed
(Lo
, False);
5518 if Is_Integer_Type
(Index
) then
5521 Left_Opnd
=> New_Copy_Tree
(Lo
),
5522 Right_Opnd
=> Length_Expr
);
5525 Make_Attribute_Reference
(Loc
,
5526 Attribute_Name
=> Name_Val
,
5527 Prefix
=> New_Occurrence_Of
(Index
, Loc
),
5528 Expressions
=> New_List
(
5531 Make_Attribute_Reference
(Loc
,
5532 Attribute_Name
=> Name_Pos
,
5533 Prefix
=> New_Occurrence_Of
(Index
, Loc
),
5534 Expressions
=> New_List
(New_Copy_Tree
(Lo
))),
5535 Right_Opnd
=> Length_Expr
)));
5542 end Make_Literal_Range
;
5544 --------------------------
5545 -- Make_Non_Empty_Check --
5546 --------------------------
5548 function Make_Non_Empty_Check
5550 N
: Node_Id
) return Node_Id
5556 Make_Attribute_Reference
(Loc
,
5557 Attribute_Name
=> Name_Length
,
5558 Prefix
=> Duplicate_Subexpr_No_Checks
(N
, Name_Req
=> True)),
5560 Make_Integer_Literal
(Loc
, 0));
5561 end Make_Non_Empty_Check
;
5563 -------------------------
5564 -- Make_Predicate_Call --
5565 -------------------------
5567 function Make_Predicate_Call
5570 Mem
: Boolean := False) return Node_Id
5572 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
5575 pragma Assert
(Present
(Predicate_Function
(Typ
)));
5577 -- Call special membership version if requested and available
5581 PFM
: constant Entity_Id
:= Predicate_Function_M
(Typ
);
5583 if Present
(PFM
) then
5585 Make_Function_Call
(Loc
,
5586 Name
=> New_Occurrence_Of
(PFM
, Loc
),
5587 Parameter_Associations
=> New_List
(Relocate_Node
(Expr
)));
5592 -- Case of calling normal predicate function
5595 Make_Function_Call
(Loc
,
5597 New_Occurrence_Of
(Predicate_Function
(Typ
), Loc
),
5598 Parameter_Associations
=> New_List
(Relocate_Node
(Expr
)));
5599 end Make_Predicate_Call
;
5601 --------------------------
5602 -- Make_Predicate_Check --
5603 --------------------------
5605 function Make_Predicate_Check
5607 Expr
: Node_Id
) return Node_Id
5609 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
5613 -- If predicate checks are suppressed, then return a null statement.
5614 -- For this call, we check only the scope setting. If the caller wants
5615 -- to check a specific entity's setting, they must do it manually.
5617 if Predicate_Checks_Suppressed
(Empty
) then
5618 return Make_Null_Statement
(Loc
);
5621 -- Compute proper name to use, we need to get this right so that the
5622 -- right set of check policies apply to the Check pragma we are making.
5624 if Has_Dynamic_Predicate_Aspect
(Typ
) then
5625 Nam
:= Name_Dynamic_Predicate
;
5626 elsif Has_Static_Predicate_Aspect
(Typ
) then
5627 Nam
:= Name_Static_Predicate
;
5629 Nam
:= Name_Predicate
;
5634 Pragma_Identifier
=> Make_Identifier
(Loc
, Name_Check
),
5635 Pragma_Argument_Associations
=> New_List
(
5636 Make_Pragma_Argument_Association
(Loc
,
5637 Expression
=> Make_Identifier
(Loc
, Nam
)),
5638 Make_Pragma_Argument_Association
(Loc
,
5639 Expression
=> Make_Predicate_Call
(Typ
, Expr
))));
5640 end Make_Predicate_Check
;
5642 ----------------------------
5643 -- Make_Subtype_From_Expr --
5644 ----------------------------
5646 -- 1. If Expr is an unconstrained array expression, creates
5647 -- Unc_Type(Expr'first(1)..Expr'last(1),..., Expr'first(n)..Expr'last(n))
5649 -- 2. If Expr is a unconstrained discriminated type expression, creates
5650 -- Unc_Type(Expr.Discr1, ... , Expr.Discr_n)
5652 -- 3. If Expr is class-wide, creates an implicit class wide subtype
5654 function Make_Subtype_From_Expr
5656 Unc_Typ
: Entity_Id
) return Node_Id
5658 Loc
: constant Source_Ptr
:= Sloc
(E
);
5659 List_Constr
: constant List_Id
:= New_List
;
5662 Full_Subtyp
: Entity_Id
;
5663 Priv_Subtyp
: Entity_Id
;
5668 if Is_Private_Type
(Unc_Typ
)
5669 and then Has_Unknown_Discriminants
(Unc_Typ
)
5671 -- Prepare the subtype completion, Go to base type to
5672 -- find underlying type, because the type may be a generic
5673 -- actual or an explicit subtype.
5675 Utyp
:= Underlying_Type
(Base_Type
(Unc_Typ
));
5676 Full_Subtyp
:= Make_Temporary
(Loc
, 'C');
5678 Unchecked_Convert_To
(Utyp
, Duplicate_Subexpr_No_Checks
(E
));
5679 Set_Parent
(Full_Exp
, Parent
(E
));
5681 Priv_Subtyp
:= Make_Temporary
(Loc
, 'P');
5684 Make_Subtype_Declaration
(Loc
,
5685 Defining_Identifier
=> Full_Subtyp
,
5686 Subtype_Indication
=> Make_Subtype_From_Expr
(Full_Exp
, Utyp
)));
5688 -- Define the dummy private subtype
5690 Set_Ekind
(Priv_Subtyp
, Subtype_Kind
(Ekind
(Unc_Typ
)));
5691 Set_Etype
(Priv_Subtyp
, Base_Type
(Unc_Typ
));
5692 Set_Scope
(Priv_Subtyp
, Full_Subtyp
);
5693 Set_Is_Constrained
(Priv_Subtyp
);
5694 Set_Is_Tagged_Type
(Priv_Subtyp
, Is_Tagged_Type
(Unc_Typ
));
5695 Set_Is_Itype
(Priv_Subtyp
);
5696 Set_Associated_Node_For_Itype
(Priv_Subtyp
, E
);
5698 if Is_Tagged_Type
(Priv_Subtyp
) then
5700 (Base_Type
(Priv_Subtyp
), Class_Wide_Type
(Unc_Typ
));
5701 Set_Direct_Primitive_Operations
(Priv_Subtyp
,
5702 Direct_Primitive_Operations
(Unc_Typ
));
5705 Set_Full_View
(Priv_Subtyp
, Full_Subtyp
);
5707 return New_Reference_To
(Priv_Subtyp
, Loc
);
5709 elsif Is_Array_Type
(Unc_Typ
) then
5710 for J
in 1 .. Number_Dimensions
(Unc_Typ
) loop
5711 Append_To
(List_Constr
,
5714 Make_Attribute_Reference
(Loc
,
5715 Prefix
=> Duplicate_Subexpr_No_Checks
(E
),
5716 Attribute_Name
=> Name_First
,
5717 Expressions
=> New_List
(
5718 Make_Integer_Literal
(Loc
, J
))),
5721 Make_Attribute_Reference
(Loc
,
5722 Prefix
=> Duplicate_Subexpr_No_Checks
(E
),
5723 Attribute_Name
=> Name_Last
,
5724 Expressions
=> New_List
(
5725 Make_Integer_Literal
(Loc
, J
)))));
5728 elsif Is_Class_Wide_Type
(Unc_Typ
) then
5730 CW_Subtype
: Entity_Id
;
5731 EQ_Typ
: Entity_Id
:= Empty
;
5734 -- A class-wide equivalent type is not needed when VM_Target
5735 -- because the VM back-ends handle the class-wide object
5736 -- initialization itself (and doesn't need or want the
5737 -- additional intermediate type to handle the assignment).
5739 if Expander_Active
and then Tagged_Type_Expansion
then
5741 -- If this is the class_wide type of a completion that is a
5742 -- record subtype, set the type of the class_wide type to be
5743 -- the full base type, for use in the expanded code for the
5744 -- equivalent type. Should this be done earlier when the
5745 -- completion is analyzed ???
5747 if Is_Private_Type
(Etype
(Unc_Typ
))
5749 Ekind
(Full_View
(Etype
(Unc_Typ
))) = E_Record_Subtype
5751 Set_Etype
(Unc_Typ
, Base_Type
(Full_View
(Etype
(Unc_Typ
))));
5754 EQ_Typ
:= Make_CW_Equivalent_Type
(Unc_Typ
, E
);
5757 CW_Subtype
:= New_Class_Wide_Subtype
(Unc_Typ
, E
);
5758 Set_Equivalent_Type
(CW_Subtype
, EQ_Typ
);
5759 Set_Cloned_Subtype
(CW_Subtype
, Base_Type
(Unc_Typ
));
5761 return New_Occurrence_Of
(CW_Subtype
, Loc
);
5764 -- Indefinite record type with discriminants
5767 D
:= First_Discriminant
(Unc_Typ
);
5768 while Present
(D
) loop
5769 Append_To
(List_Constr
,
5770 Make_Selected_Component
(Loc
,
5771 Prefix
=> Duplicate_Subexpr_No_Checks
(E
),
5772 Selector_Name
=> New_Reference_To
(D
, Loc
)));
5774 Next_Discriminant
(D
);
5779 Make_Subtype_Indication
(Loc
,
5780 Subtype_Mark
=> New_Reference_To
(Unc_Typ
, Loc
),
5782 Make_Index_Or_Discriminant_Constraint
(Loc
,
5783 Constraints
=> List_Constr
));
5784 end Make_Subtype_From_Expr
;
5786 -----------------------------
5787 -- May_Generate_Large_Temp --
5788 -----------------------------
5790 -- At the current time, the only types that we return False for (i.e. where
5791 -- we decide we know they cannot generate large temps) are ones where we
5792 -- know the size is 256 bits or less at compile time, and we are still not
5793 -- doing a thorough job on arrays and records ???
5795 function May_Generate_Large_Temp
(Typ
: Entity_Id
) return Boolean is
5797 if not Size_Known_At_Compile_Time
(Typ
) then
5800 elsif Esize
(Typ
) /= 0 and then Esize
(Typ
) <= 256 then
5803 elsif Is_Array_Type
(Typ
) and then Present
(Packed_Array_Type
(Typ
)) then
5804 return May_Generate_Large_Temp
(Packed_Array_Type
(Typ
));
5806 -- We could do more here to find other small types ???
5811 end May_Generate_Large_Temp
;
5813 ------------------------
5814 -- Needs_Finalization --
5815 ------------------------
5817 function Needs_Finalization
(T
: Entity_Id
) return Boolean is
5818 function Has_Some_Controlled_Component
(Rec
: Entity_Id
) return Boolean;
5819 -- If type is not frozen yet, check explicitly among its components,
5820 -- because the Has_Controlled_Component flag is not necessarily set.
5822 -----------------------------------
5823 -- Has_Some_Controlled_Component --
5824 -----------------------------------
5826 function Has_Some_Controlled_Component
5827 (Rec
: Entity_Id
) return Boolean
5832 if Has_Controlled_Component
(Rec
) then
5835 elsif not Is_Frozen
(Rec
) then
5836 if Is_Record_Type
(Rec
) then
5837 Comp
:= First_Entity
(Rec
);
5839 while Present
(Comp
) loop
5840 if not Is_Type
(Comp
)
5841 and then Needs_Finalization
(Etype
(Comp
))
5851 elsif Is_Array_Type
(Rec
) then
5852 return Needs_Finalization
(Component_Type
(Rec
));
5855 return Has_Controlled_Component
(Rec
);
5860 end Has_Some_Controlled_Component
;
5862 -- Start of processing for Needs_Finalization
5865 -- Certain run-time configurations and targets do not provide support
5866 -- for controlled types.
5868 if Restriction_Active
(No_Finalization
) then
5871 -- C, C++, CIL and Java types are not considered controlled. It is
5872 -- assumed that the non-Ada side will handle their clean up.
5874 elsif Convention
(T
) = Convention_C
5875 or else Convention
(T
) = Convention_CIL
5876 or else Convention
(T
) = Convention_CPP
5877 or else Convention
(T
) = Convention_Java
5882 -- Class-wide types are treated as controlled because derivations
5883 -- from the root type can introduce controlled components.
5886 Is_Class_Wide_Type
(T
)
5887 or else Is_Controlled
(T
)
5888 or else Has_Controlled_Component
(T
)
5889 or else Has_Some_Controlled_Component
(T
)
5891 (Is_Concurrent_Type
(T
)
5892 and then Present
(Corresponding_Record_Type
(T
))
5893 and then Needs_Finalization
(Corresponding_Record_Type
(T
)));
5895 end Needs_Finalization
;
5897 ----------------------------
5898 -- Needs_Constant_Address --
5899 ----------------------------
5901 function Needs_Constant_Address
5903 Typ
: Entity_Id
) return Boolean
5907 -- If we have no initialization of any kind, then we don't need to place
5908 -- any restrictions on the address clause, because the object will be
5909 -- elaborated after the address clause is evaluated. This happens if the
5910 -- declaration has no initial expression, or the type has no implicit
5911 -- initialization, or the object is imported.
5913 -- The same holds for all initialized scalar types and all access types.
5914 -- Packed bit arrays of size up to 64 are represented using a modular
5915 -- type with an initialization (to zero) and can be processed like other
5916 -- initialized scalar types.
5918 -- If the type is controlled, code to attach the object to a
5919 -- finalization chain is generated at the point of declaration, and
5920 -- therefore the elaboration of the object cannot be delayed: the
5921 -- address expression must be a constant.
5923 if No
(Expression
(Decl
))
5924 and then not Needs_Finalization
(Typ
)
5926 (not Has_Non_Null_Base_Init_Proc
(Typ
)
5927 or else Is_Imported
(Defining_Identifier
(Decl
)))
5931 elsif (Present
(Expression
(Decl
)) and then Is_Scalar_Type
(Typ
))
5932 or else Is_Access_Type
(Typ
)
5934 (Is_Bit_Packed_Array
(Typ
)
5935 and then Is_Modular_Integer_Type
(Packed_Array_Type
(Typ
)))
5941 -- Otherwise, we require the address clause to be constant because
5942 -- the call to the initialization procedure (or the attach code) has
5943 -- to happen at the point of the declaration.
5945 -- Actually the IP call has been moved to the freeze actions anyway,
5946 -- so maybe we can relax this restriction???
5950 end Needs_Constant_Address
;
5952 ----------------------------
5953 -- New_Class_Wide_Subtype --
5954 ----------------------------
5956 function New_Class_Wide_Subtype
5957 (CW_Typ
: Entity_Id
;
5958 N
: Node_Id
) return Entity_Id
5960 Res
: constant Entity_Id
:= Create_Itype
(E_Void
, N
);
5961 Res_Name
: constant Name_Id
:= Chars
(Res
);
5962 Res_Scope
: constant Entity_Id
:= Scope
(Res
);
5965 Copy_Node
(CW_Typ
, Res
);
5966 Set_Comes_From_Source
(Res
, False);
5967 Set_Sloc
(Res
, Sloc
(N
));
5969 Set_Associated_Node_For_Itype
(Res
, N
);
5970 Set_Is_Public
(Res
, False); -- By default, may be changed below.
5971 Set_Public_Status
(Res
);
5972 Set_Chars
(Res
, Res_Name
);
5973 Set_Scope
(Res
, Res_Scope
);
5974 Set_Ekind
(Res
, E_Class_Wide_Subtype
);
5975 Set_Next_Entity
(Res
, Empty
);
5976 Set_Etype
(Res
, Base_Type
(CW_Typ
));
5977 Set_Is_Frozen
(Res
, False);
5978 Set_Freeze_Node
(Res
, Empty
);
5980 end New_Class_Wide_Subtype
;
5982 --------------------------------
5983 -- Non_Limited_Designated_Type --
5984 ---------------------------------
5986 function Non_Limited_Designated_Type
(T
: Entity_Id
) return Entity_Id
is
5987 Desig
: constant Entity_Id
:= Designated_Type
(T
);
5989 if Ekind
(Desig
) = E_Incomplete_Type
5990 and then Present
(Non_Limited_View
(Desig
))
5992 return Non_Limited_View
(Desig
);
5996 end Non_Limited_Designated_Type
;
5998 -----------------------------------
5999 -- OK_To_Do_Constant_Replacement --
6000 -----------------------------------
6002 function OK_To_Do_Constant_Replacement
(E
: Entity_Id
) return Boolean is
6003 ES
: constant Entity_Id
:= Scope
(E
);
6007 -- Do not replace statically allocated objects, because they may be
6008 -- modified outside the current scope.
6010 if Is_Statically_Allocated
(E
) then
6013 -- Do not replace aliased or volatile objects, since we don't know what
6014 -- else might change the value.
6016 elsif Is_Aliased
(E
) or else Treat_As_Volatile
(E
) then
6019 -- Debug flag -gnatdM disconnects this optimization
6021 elsif Debug_Flag_MM
then
6024 -- Otherwise check scopes
6027 CS
:= Current_Scope
;
6030 -- If we are in right scope, replacement is safe
6035 -- Packages do not affect the determination of safety
6037 elsif Ekind
(CS
) = E_Package
then
6038 exit when CS
= Standard_Standard
;
6041 -- Blocks do not affect the determination of safety
6043 elsif Ekind
(CS
) = E_Block
then
6046 -- Loops do not affect the determination of safety. Note that we
6047 -- kill all current values on entry to a loop, so we are just
6048 -- talking about processing within a loop here.
6050 elsif Ekind
(CS
) = E_Loop
then
6053 -- Otherwise, the reference is dubious, and we cannot be sure that
6054 -- it is safe to do the replacement.
6063 end OK_To_Do_Constant_Replacement
;
6065 ------------------------------------
6066 -- Possible_Bit_Aligned_Component --
6067 ------------------------------------
6069 function Possible_Bit_Aligned_Component
(N
: Node_Id
) return Boolean is
6073 -- Case of indexed component
6075 when N_Indexed_Component
=>
6077 P
: constant Node_Id
:= Prefix
(N
);
6078 Ptyp
: constant Entity_Id
:= Etype
(P
);
6081 -- If we know the component size and it is less than 64, then
6082 -- we are definitely OK. The back end always does assignment of
6083 -- misaligned small objects correctly.
6085 if Known_Static_Component_Size
(Ptyp
)
6086 and then Component_Size
(Ptyp
) <= 64
6090 -- Otherwise, we need to test the prefix, to see if we are
6091 -- indexing from a possibly unaligned component.
6094 return Possible_Bit_Aligned_Component
(P
);
6098 -- Case of selected component
6100 when N_Selected_Component
=>
6102 P
: constant Node_Id
:= Prefix
(N
);
6103 Comp
: constant Entity_Id
:= Entity
(Selector_Name
(N
));
6106 -- If there is no component clause, then we are in the clear
6107 -- since the back end will never misalign a large component
6108 -- unless it is forced to do so. In the clear means we need
6109 -- only the recursive test on the prefix.
6111 if Component_May_Be_Bit_Aligned
(Comp
) then
6114 return Possible_Bit_Aligned_Component
(P
);
6118 -- For a slice, test the prefix, if that is possibly misaligned,
6119 -- then for sure the slice is!
6122 return Possible_Bit_Aligned_Component
(Prefix
(N
));
6124 -- For an unchecked conversion, check whether the expression may
6127 when N_Unchecked_Type_Conversion
=>
6128 return Possible_Bit_Aligned_Component
(Expression
(N
));
6130 -- If we have none of the above, it means that we have fallen off the
6131 -- top testing prefixes recursively, and we now have a stand alone
6132 -- object, where we don't have a problem.
6138 end Possible_Bit_Aligned_Component
;
6140 -----------------------------------------------
6141 -- Process_Statements_For_Controlled_Objects --
6142 -----------------------------------------------
6144 procedure Process_Statements_For_Controlled_Objects
(N
: Node_Id
) is
6145 Loc
: constant Source_Ptr
:= Sloc
(N
);
6147 function Are_Wrapped
(L
: List_Id
) return Boolean;
6148 -- Determine whether list L contains only one statement which is a block
6150 function Wrap_Statements_In_Block
(L
: List_Id
) return Node_Id
;
6151 -- Given a list of statements L, wrap it in a block statement and return
6152 -- the generated node.
6158 function Are_Wrapped
(L
: List_Id
) return Boolean is
6159 Stmt
: constant Node_Id
:= First
(L
);
6163 and then No
(Next
(Stmt
))
6164 and then Nkind
(Stmt
) = N_Block_Statement
;
6167 ------------------------------
6168 -- Wrap_Statements_In_Block --
6169 ------------------------------
6171 function Wrap_Statements_In_Block
(L
: List_Id
) return Node_Id
is
6174 Make_Block_Statement
(Loc
,
6175 Declarations
=> No_List
,
6176 Handled_Statement_Sequence
=>
6177 Make_Handled_Sequence_Of_Statements
(Loc
,
6179 end Wrap_Statements_In_Block
;
6185 -- Start of processing for Process_Statements_For_Controlled_Objects
6188 -- Whenever a non-handled statement list is wrapped in a block, the
6189 -- block must be explicitly analyzed to redecorate all entities in the
6190 -- list and ensure that a finalizer is properly built.
6195 N_Conditional_Entry_Call |
6196 N_Selective_Accept
=>
6198 -- Check the "then statements" for elsif parts and if statements
6200 if Nkind_In
(N
, N_Elsif_Part
, N_If_Statement
)
6201 and then not Is_Empty_List
(Then_Statements
(N
))
6202 and then not Are_Wrapped
(Then_Statements
(N
))
6203 and then Requires_Cleanup_Actions
6204 (Then_Statements
(N
), False, False)
6206 Block
:= Wrap_Statements_In_Block
(Then_Statements
(N
));
6207 Set_Then_Statements
(N
, New_List
(Block
));
6212 -- Check the "else statements" for conditional entry calls, if
6213 -- statements and selective accepts.
6215 if Nkind_In
(N
, N_Conditional_Entry_Call
,
6218 and then not Is_Empty_List
(Else_Statements
(N
))
6219 and then not Are_Wrapped
(Else_Statements
(N
))
6220 and then Requires_Cleanup_Actions
6221 (Else_Statements
(N
), False, False)
6223 Block
:= Wrap_Statements_In_Block
(Else_Statements
(N
));
6224 Set_Else_Statements
(N
, New_List
(Block
));
6229 when N_Abortable_Part |
6230 N_Accept_Alternative |
6231 N_Case_Statement_Alternative |
6232 N_Delay_Alternative |
6233 N_Entry_Call_Alternative |
6234 N_Exception_Handler |
6236 N_Triggering_Alternative
=>
6238 if not Is_Empty_List
(Statements
(N
))
6239 and then not Are_Wrapped
(Statements
(N
))
6240 and then Requires_Cleanup_Actions
(Statements
(N
), False, False)
6242 Block
:= Wrap_Statements_In_Block
(Statements
(N
));
6243 Set_Statements
(N
, New_List
(Block
));
6251 end Process_Statements_For_Controlled_Objects
;
6253 ----------------------
6254 -- Remove_Init_Call --
6255 ----------------------
6257 function Remove_Init_Call
6259 Rep_Clause
: Node_Id
) return Node_Id
6261 Par
: constant Node_Id
:= Parent
(Var
);
6262 Typ
: constant Entity_Id
:= Etype
(Var
);
6264 Init_Proc
: Entity_Id
;
6265 -- Initialization procedure for Typ
6267 function Find_Init_Call_In_List
(From
: Node_Id
) return Node_Id
;
6268 -- Look for init call for Var starting at From and scanning the
6269 -- enclosing list until Rep_Clause or the end of the list is reached.
6271 ----------------------------
6272 -- Find_Init_Call_In_List --
6273 ----------------------------
6275 function Find_Init_Call_In_List
(From
: Node_Id
) return Node_Id
is
6276 Init_Call
: Node_Id
;
6280 while Present
(Init_Call
) and then Init_Call
/= Rep_Clause
loop
6281 if Nkind
(Init_Call
) = N_Procedure_Call_Statement
6282 and then Is_Entity_Name
(Name
(Init_Call
))
6283 and then Entity
(Name
(Init_Call
)) = Init_Proc
6292 end Find_Init_Call_In_List
;
6294 Init_Call
: Node_Id
;
6296 -- Start of processing for Find_Init_Call
6299 if Present
(Initialization_Statements
(Var
)) then
6300 Init_Call
:= Initialization_Statements
(Var
);
6301 Set_Initialization_Statements
(Var
, Empty
);
6303 elsif not Has_Non_Null_Base_Init_Proc
(Typ
) then
6305 -- No init proc for the type, so obviously no call to be found
6310 -- We might be able to handle other cases below by just properly
6311 -- setting Initialization_Statements at the point where the init proc
6312 -- call is generated???
6314 Init_Proc
:= Base_Init_Proc
(Typ
);
6316 -- First scan the list containing the declaration of Var
6318 Init_Call
:= Find_Init_Call_In_List
(From
=> Next
(Par
));
6320 -- If not found, also look on Var's freeze actions list, if any,
6321 -- since the init call may have been moved there (case of an address
6322 -- clause applying to Var).
6324 if No
(Init_Call
) and then Present
(Freeze_Node
(Var
)) then
6326 Find_Init_Call_In_List
(First
(Actions
(Freeze_Node
(Var
))));
6329 -- If the initialization call has actuals that use the secondary
6330 -- stack, the call may have been wrapped into a temporary block, in
6331 -- which case the block itself has to be removed.
6333 if No
(Init_Call
) and then Nkind
(Next
(Par
)) = N_Block_Statement
then
6335 Blk
: constant Node_Id
:= Next
(Par
);
6338 (Find_Init_Call_In_List
6339 (First
(Statements
(Handled_Statement_Sequence
(Blk
)))))
6347 if Present
(Init_Call
) then
6351 end Remove_Init_Call
;
6353 -------------------------
6354 -- Remove_Side_Effects --
6355 -------------------------
6357 procedure Remove_Side_Effects
6359 Name_Req
: Boolean := False;
6360 Variable_Ref
: Boolean := False)
6362 Loc
: constant Source_Ptr
:= Sloc
(Exp
);
6363 Exp_Type
: constant Entity_Id
:= Etype
(Exp
);
6364 Svg_Suppress
: constant Suppress_Record
:= Scope_Suppress
;
6368 Ptr_Typ_Decl
: Node_Id
;
6369 Ref_Type
: Entity_Id
;
6372 function Side_Effect_Free
(N
: Node_Id
) return Boolean;
6373 -- Determines if the tree N represents an expression that is known not
6374 -- to have side effects, and for which no processing is required.
6376 function Side_Effect_Free
(L
: List_Id
) return Boolean;
6377 -- Determines if all elements of the list L are side effect free
6379 function Safe_Prefixed_Reference
(N
: Node_Id
) return Boolean;
6380 -- The argument N is a construct where the Prefix is dereferenced if it
6381 -- is an access type and the result is a variable. The call returns True
6382 -- if the construct is side effect free (not considering side effects in
6383 -- other than the prefix which are to be tested by the caller).
6385 function Within_In_Parameter
(N
: Node_Id
) return Boolean;
6386 -- Determines if N is a subcomponent of a composite in-parameter. If so,
6387 -- N is not side-effect free when the actual is global and modifiable
6388 -- indirectly from within a subprogram, because it may be passed by
6389 -- reference. The front-end must be conservative here and assume that
6390 -- this may happen with any array or record type. On the other hand, we
6391 -- cannot create temporaries for all expressions for which this
6392 -- condition is true, for various reasons that might require clearing up
6393 -- ??? For example, discriminant references that appear out of place, or
6394 -- spurious type errors with class-wide expressions. As a result, we
6395 -- limit the transformation to loop bounds, which is so far the only
6396 -- case that requires it.
6398 -----------------------------
6399 -- Safe_Prefixed_Reference --
6400 -----------------------------
6402 function Safe_Prefixed_Reference
(N
: Node_Id
) return Boolean is
6404 -- If prefix is not side effect free, definitely not safe
6406 if not Side_Effect_Free
(Prefix
(N
)) then
6409 -- If the prefix is of an access type that is not access-to-constant,
6410 -- then this construct is a variable reference, which means it is to
6411 -- be considered to have side effects if Variable_Ref is set True.
6413 elsif Is_Access_Type
(Etype
(Prefix
(N
)))
6414 and then not Is_Access_Constant
(Etype
(Prefix
(N
)))
6415 and then Variable_Ref
6417 -- Exception is a prefix that is the result of a previous removal
6420 return Is_Entity_Name
(Prefix
(N
))
6421 and then not Comes_From_Source
(Prefix
(N
))
6422 and then Ekind
(Entity
(Prefix
(N
))) = E_Constant
6423 and then Is_Internal_Name
(Chars
(Entity
(Prefix
(N
))));
6425 -- If the prefix is an explicit dereference then this construct is a
6426 -- variable reference, which means it is to be considered to have
6427 -- side effects if Variable_Ref is True.
6429 -- We do NOT exclude dereferences of access-to-constant types because
6430 -- we handle them as constant view of variables.
6432 elsif Nkind
(Prefix
(N
)) = N_Explicit_Dereference
6433 and then Variable_Ref
6437 -- Note: The following test is the simplest way of solving a complex
6438 -- problem uncovered by the following test (Side effect on loop bound
6439 -- that is a subcomponent of a global variable:
6441 -- with Text_Io; use Text_Io;
6442 -- procedure Tloop is
6445 -- V : Natural := 4;
6446 -- S : String (1..5) := (others => 'a');
6453 -- with procedure Action;
6454 -- procedure Loop_G (Arg : X; Msg : String)
6456 -- procedure Loop_G (Arg : X; Msg : String) is
6458 -- Put_Line ("begin loop_g " & Msg & " will loop till: "
6459 -- & Natural'Image (Arg.V));
6460 -- for Index in 1 .. Arg.V loop
6462 -- (Natural'Image (Index) & " " & Arg.S (Index));
6463 -- if Index > 2 then
6467 -- Put_Line ("end loop_g " & Msg);
6470 -- procedure Loop1 is new Loop_G (Modi);
6471 -- procedure Modi is
6474 -- Loop1 (X1, "from modi");
6478 -- Loop1 (X1, "initial");
6481 -- The output of the above program should be:
6483 -- begin loop_g initial will loop till: 4
6487 -- begin loop_g from modi will loop till: 1
6489 -- end loop_g from modi
6491 -- begin loop_g from modi will loop till: 1
6493 -- end loop_g from modi
6494 -- end loop_g initial
6496 -- If a loop bound is a subcomponent of a global variable, a
6497 -- modification of that variable within the loop may incorrectly
6498 -- affect the execution of the loop.
6500 elsif Nkind
(Parent
(Parent
(N
))) = N_Loop_Parameter_Specification
6501 and then Within_In_Parameter
(Prefix
(N
))
6502 and then Variable_Ref
6506 -- All other cases are side effect free
6511 end Safe_Prefixed_Reference
;
6513 ----------------------
6514 -- Side_Effect_Free --
6515 ----------------------
6517 function Side_Effect_Free
(N
: Node_Id
) return Boolean is
6519 -- Note on checks that could raise Constraint_Error. Strictly, if we
6520 -- take advantage of 11.6, these checks do not count as side effects.
6521 -- However, we would prefer to consider that they are side effects,
6522 -- since the backend CSE does not work very well on expressions which
6523 -- can raise Constraint_Error. On the other hand if we don't consider
6524 -- them to be side effect free, then we get some awkward expansions
6525 -- in -gnato mode, resulting in code insertions at a point where we
6526 -- do not have a clear model for performing the insertions.
6528 -- Special handling for entity names
6530 if Is_Entity_Name
(N
) then
6532 -- Variables are considered to be a side effect if Variable_Ref
6533 -- is set or if we have a volatile reference and Name_Req is off.
6534 -- If Name_Req is True then we can't help returning a name which
6535 -- effectively allows multiple references in any case.
6537 if Is_Variable
(N
, Use_Original_Node
=> False) then
6538 return not Variable_Ref
6539 and then (not Is_Volatile_Reference
(N
) or else Name_Req
);
6541 -- Any other entity (e.g. a subtype name) is definitely side
6548 -- A value known at compile time is always side effect free
6550 elsif Compile_Time_Known_Value
(N
) then
6553 -- A variable renaming is not side-effect free, because the renaming
6554 -- will function like a macro in the front-end in some cases, and an
6555 -- assignment can modify the component designated by N, so we need to
6556 -- create a temporary for it.
6558 -- The guard testing for Entity being present is needed at least in
6559 -- the case of rewritten predicate expressions, and may well also be
6560 -- appropriate elsewhere. Obviously we can't go testing the entity
6561 -- field if it does not exist, so it's reasonable to say that this is
6562 -- not the renaming case if it does not exist.
6564 elsif Is_Entity_Name
(Original_Node
(N
))
6565 and then Present
(Entity
(Original_Node
(N
)))
6566 and then Is_Renaming_Of_Object
(Entity
(Original_Node
(N
)))
6567 and then Ekind
(Entity
(Original_Node
(N
))) /= E_Constant
6570 RO
: constant Node_Id
:=
6571 Renamed_Object
(Entity
(Original_Node
(N
)));
6574 -- If the renamed object is an indexed component, or an
6575 -- explicit dereference, then the designated object could
6576 -- be modified by an assignment.
6578 if Nkind_In
(RO
, N_Indexed_Component
,
6579 N_Explicit_Dereference
)
6583 -- A selected component must have a safe prefix
6585 elsif Nkind
(RO
) = N_Selected_Component
then
6586 return Safe_Prefixed_Reference
(RO
);
6588 -- In all other cases, designated object cannot be changed so
6589 -- we are side effect free.
6596 -- Remove_Side_Effects generates an object renaming declaration to
6597 -- capture the expression of a class-wide expression. In VM targets
6598 -- the frontend performs no expansion for dispatching calls to
6599 -- class- wide types since they are handled by the VM. Hence, we must
6600 -- locate here if this node corresponds to a previous invocation of
6601 -- Remove_Side_Effects to avoid a never ending loop in the frontend.
6603 elsif VM_Target
/= No_VM
6604 and then not Comes_From_Source
(N
)
6605 and then Nkind
(Parent
(N
)) = N_Object_Renaming_Declaration
6606 and then Is_Class_Wide_Type
(Etype
(N
))
6611 -- For other than entity names and compile time known values,
6612 -- check the node kind for special processing.
6616 -- An attribute reference is side effect free if its expressions
6617 -- are side effect free and its prefix is side effect free or
6618 -- is an entity reference.
6620 -- Is this right? what about x'first where x is a variable???
6622 when N_Attribute_Reference
=>
6623 return Side_Effect_Free
(Expressions
(N
))
6624 and then Attribute_Name
(N
) /= Name_Input
6625 and then (Is_Entity_Name
(Prefix
(N
))
6626 or else Side_Effect_Free
(Prefix
(N
)));
6628 -- A binary operator is side effect free if and both operands are
6629 -- side effect free. For this purpose binary operators include
6630 -- membership tests and short circuit forms.
6632 when N_Binary_Op | N_Membership_Test | N_Short_Circuit
=>
6633 return Side_Effect_Free
(Left_Opnd
(N
))
6635 Side_Effect_Free
(Right_Opnd
(N
));
6637 -- An explicit dereference is side effect free only if it is
6638 -- a side effect free prefixed reference.
6640 when N_Explicit_Dereference
=>
6641 return Safe_Prefixed_Reference
(N
);
6643 -- A call to _rep_to_pos is side effect free, since we generate
6644 -- this pure function call ourselves. Moreover it is critically
6645 -- important to make this exception, since otherwise we can have
6646 -- discriminants in array components which don't look side effect
6647 -- free in the case of an array whose index type is an enumeration
6648 -- type with an enumeration rep clause.
6650 -- All other function calls are not side effect free
6652 when N_Function_Call
=>
6653 return Nkind
(Name
(N
)) = N_Identifier
6654 and then Is_TSS
(Name
(N
), TSS_Rep_To_Pos
)
6656 Side_Effect_Free
(First
(Parameter_Associations
(N
)));
6658 -- An indexed component is side effect free if it is a side
6659 -- effect free prefixed reference and all the indexing
6660 -- expressions are side effect free.
6662 when N_Indexed_Component
=>
6663 return Side_Effect_Free
(Expressions
(N
))
6664 and then Safe_Prefixed_Reference
(N
);
6666 -- A type qualification is side effect free if the expression
6667 -- is side effect free.
6669 when N_Qualified_Expression
=>
6670 return Side_Effect_Free
(Expression
(N
));
6672 -- A selected component is side effect free only if it is a side
6673 -- effect free prefixed reference. If it designates a component
6674 -- with a rep. clause it must be treated has having a potential
6675 -- side effect, because it may be modified through a renaming, and
6676 -- a subsequent use of the renaming as a macro will yield the
6677 -- wrong value. This complex interaction between renaming and
6678 -- removing side effects is a reminder that the latter has become
6679 -- a headache to maintain, and that it should be removed in favor
6680 -- of the gcc mechanism to capture values ???
6682 when N_Selected_Component
=>
6683 if Nkind
(Parent
(N
)) = N_Explicit_Dereference
6684 and then Has_Non_Standard_Rep
(Designated_Type
(Etype
(N
)))
6688 return Safe_Prefixed_Reference
(N
);
6691 -- A range is side effect free if the bounds are side effect free
6694 return Side_Effect_Free
(Low_Bound
(N
))
6695 and then Side_Effect_Free
(High_Bound
(N
));
6697 -- A slice is side effect free if it is a side effect free
6698 -- prefixed reference and the bounds are side effect free.
6701 return Side_Effect_Free
(Discrete_Range
(N
))
6702 and then Safe_Prefixed_Reference
(N
);
6704 -- A type conversion is side effect free if the expression to be
6705 -- converted is side effect free.
6707 when N_Type_Conversion
=>
6708 return Side_Effect_Free
(Expression
(N
));
6710 -- A unary operator is side effect free if the operand
6711 -- is side effect free.
6714 return Side_Effect_Free
(Right_Opnd
(N
));
6716 -- An unchecked type conversion is side effect free only if it
6717 -- is safe and its argument is side effect free.
6719 when N_Unchecked_Type_Conversion
=>
6720 return Safe_Unchecked_Type_Conversion
(N
)
6721 and then Side_Effect_Free
(Expression
(N
));
6723 -- An unchecked expression is side effect free if its expression
6724 -- is side effect free.
6726 when N_Unchecked_Expression
=>
6727 return Side_Effect_Free
(Expression
(N
));
6729 -- A literal is side effect free
6731 when N_Character_Literal |
6737 -- We consider that anything else has side effects. This is a bit
6738 -- crude, but we are pretty close for most common cases, and we
6739 -- are certainly correct (i.e. we never return True when the
6740 -- answer should be False).
6745 end Side_Effect_Free
;
6747 -- A list is side effect free if all elements of the list are side
6750 function Side_Effect_Free
(L
: List_Id
) return Boolean is
6754 if L
= No_List
or else L
= Error_List
then
6759 while Present
(N
) loop
6760 if not Side_Effect_Free
(N
) then
6769 end Side_Effect_Free
;
6771 -------------------------
6772 -- Within_In_Parameter --
6773 -------------------------
6775 function Within_In_Parameter
(N
: Node_Id
) return Boolean is
6777 if not Comes_From_Source
(N
) then
6780 elsif Is_Entity_Name
(N
) then
6781 return Ekind
(Entity
(N
)) = E_In_Parameter
;
6783 elsif Nkind_In
(N
, N_Indexed_Component
, N_Selected_Component
) then
6784 return Within_In_Parameter
(Prefix
(N
));
6789 end Within_In_Parameter
;
6791 -- Start of processing for Remove_Side_Effects
6794 -- Handle cases in which there is nothing to do
6796 if not Expander_Active
then
6800 -- Cannot generate temporaries if the invocation to remove side effects
6801 -- was issued too early and the type of the expression is not resolved
6802 -- (this happens because routines Duplicate_Subexpr_XX implicitly invoke
6803 -- Remove_Side_Effects).
6806 or else Ekind
(Exp_Type
) = E_Access_Attribute_Type
6810 -- No action needed for side-effect free expressions
6812 elsif Side_Effect_Free
(Exp
) then
6816 -- The remaining procesaing is done with all checks suppressed
6818 -- Note: from now on, don't use return statements, instead do a goto
6819 -- Leave, to ensure that we properly restore Scope_Suppress.Suppress.
6821 Scope_Suppress
.Suppress
:= (others => True);
6823 -- If it is a scalar type and we need to capture the value, just make
6824 -- a copy. Likewise for a function call, an attribute reference, an
6825 -- allocator, or an operator. And if we have a volatile reference and
6826 -- Name_Req is not set (see comments above for Side_Effect_Free).
6828 if Is_Elementary_Type
(Exp_Type
)
6829 and then (Variable_Ref
6830 or else Nkind_In
(Exp
, N_Function_Call
,
6831 N_Attribute_Reference
,
6833 or else Nkind
(Exp
) in N_Op
6834 or else (not Name_Req
and then Is_Volatile_Reference
(Exp
)))
6836 Def_Id
:= Make_Temporary
(Loc
, 'R', Exp
);
6837 Set_Etype
(Def_Id
, Exp_Type
);
6838 Res
:= New_Reference_To
(Def_Id
, Loc
);
6840 -- If the expression is a packed reference, it must be reanalyzed and
6841 -- expanded, depending on context. This is the case for actuals where
6842 -- a constraint check may capture the actual before expansion of the
6843 -- call is complete.
6845 if Nkind
(Exp
) = N_Indexed_Component
6846 and then Is_Packed
(Etype
(Prefix
(Exp
)))
6848 Set_Analyzed
(Exp
, False);
6849 Set_Analyzed
(Prefix
(Exp
), False);
6853 Make_Object_Declaration
(Loc
,
6854 Defining_Identifier
=> Def_Id
,
6855 Object_Definition
=> New_Reference_To
(Exp_Type
, Loc
),
6856 Constant_Present
=> True,
6857 Expression
=> Relocate_Node
(Exp
));
6859 Set_Assignment_OK
(E
);
6860 Insert_Action
(Exp
, E
);
6862 -- If the expression has the form v.all then we can just capture the
6863 -- pointer, and then do an explicit dereference on the result.
6865 elsif Nkind
(Exp
) = N_Explicit_Dereference
then
6866 Def_Id
:= Make_Temporary
(Loc
, 'R', Exp
);
6868 Make_Explicit_Dereference
(Loc
, New_Reference_To
(Def_Id
, Loc
));
6871 Make_Object_Declaration
(Loc
,
6872 Defining_Identifier
=> Def_Id
,
6873 Object_Definition
=>
6874 New_Reference_To
(Etype
(Prefix
(Exp
)), Loc
),
6875 Constant_Present
=> True,
6876 Expression
=> Relocate_Node
(Prefix
(Exp
))));
6878 -- Similar processing for an unchecked conversion of an expression of
6879 -- the form v.all, where we want the same kind of treatment.
6881 elsif Nkind
(Exp
) = N_Unchecked_Type_Conversion
6882 and then Nkind
(Expression
(Exp
)) = N_Explicit_Dereference
6884 Remove_Side_Effects
(Expression
(Exp
), Name_Req
, Variable_Ref
);
6887 -- If this is a type conversion, leave the type conversion and remove
6888 -- the side effects in the expression. This is important in several
6889 -- circumstances: for change of representations, and also when this is a
6890 -- view conversion to a smaller object, where gigi can end up creating
6891 -- its own temporary of the wrong size.
6893 elsif Nkind
(Exp
) = N_Type_Conversion
then
6894 Remove_Side_Effects
(Expression
(Exp
), Name_Req
, Variable_Ref
);
6897 -- If this is an unchecked conversion that Gigi can't handle, make
6898 -- a copy or a use a renaming to capture the value.
6900 elsif Nkind
(Exp
) = N_Unchecked_Type_Conversion
6901 and then not Safe_Unchecked_Type_Conversion
(Exp
)
6903 if CW_Or_Has_Controlled_Part
(Exp_Type
) then
6905 -- Use a renaming to capture the expression, rather than create
6906 -- a controlled temporary.
6908 Def_Id
:= Make_Temporary
(Loc
, 'R', Exp
);
6909 Res
:= New_Reference_To
(Def_Id
, Loc
);
6912 Make_Object_Renaming_Declaration
(Loc
,
6913 Defining_Identifier
=> Def_Id
,
6914 Subtype_Mark
=> New_Reference_To
(Exp_Type
, Loc
),
6915 Name
=> Relocate_Node
(Exp
)));
6918 Def_Id
:= Make_Temporary
(Loc
, 'R', Exp
);
6919 Set_Etype
(Def_Id
, Exp_Type
);
6920 Res
:= New_Reference_To
(Def_Id
, Loc
);
6923 Make_Object_Declaration
(Loc
,
6924 Defining_Identifier
=> Def_Id
,
6925 Object_Definition
=> New_Reference_To
(Exp_Type
, Loc
),
6926 Constant_Present
=> not Is_Variable
(Exp
),
6927 Expression
=> Relocate_Node
(Exp
));
6929 Set_Assignment_OK
(E
);
6930 Insert_Action
(Exp
, E
);
6933 -- For expressions that denote objects, we can use a renaming scheme.
6934 -- This is needed for correctness in the case of a volatile object of
6935 -- a non-volatile type because the Make_Reference call of the "default"
6936 -- approach would generate an illegal access value (an access value
6937 -- cannot designate such an object - see Analyze_Reference). We skip
6938 -- using this scheme if we have an object of a volatile type and we do
6939 -- not have Name_Req set true (see comments above for Side_Effect_Free).
6941 -- In Ada 2012 a qualified expression is an object, but for purposes of
6942 -- removing side effects it still need to be transformed into a separate
6943 -- declaration, particularly if the expression is an aggregate.
6945 elsif Is_Object_Reference
(Exp
)
6946 and then Nkind
(Exp
) /= N_Function_Call
6947 and then Nkind
(Exp
) /= N_Qualified_Expression
6948 and then (Name_Req
or else not Treat_As_Volatile
(Exp_Type
))
6950 Def_Id
:= Make_Temporary
(Loc
, 'R', Exp
);
6952 if Nkind
(Exp
) = N_Selected_Component
6953 and then Nkind
(Prefix
(Exp
)) = N_Function_Call
6954 and then Is_Array_Type
(Exp_Type
)
6956 -- Avoid generating a variable-sized temporary, by generating
6957 -- the renaming declaration just for the function call. The
6958 -- transformation could be refined to apply only when the array
6959 -- component is constrained by a discriminant???
6962 Make_Selected_Component
(Loc
,
6963 Prefix
=> New_Occurrence_Of
(Def_Id
, Loc
),
6964 Selector_Name
=> Selector_Name
(Exp
));
6967 Make_Object_Renaming_Declaration
(Loc
,
6968 Defining_Identifier
=> Def_Id
,
6970 New_Reference_To
(Base_Type
(Etype
(Prefix
(Exp
))), Loc
),
6971 Name
=> Relocate_Node
(Prefix
(Exp
))));
6974 Res
:= New_Reference_To
(Def_Id
, Loc
);
6977 Make_Object_Renaming_Declaration
(Loc
,
6978 Defining_Identifier
=> Def_Id
,
6979 Subtype_Mark
=> New_Reference_To
(Exp_Type
, Loc
),
6980 Name
=> Relocate_Node
(Exp
)));
6983 -- If this is a packed reference, or a selected component with
6984 -- a non-standard representation, a reference to the temporary
6985 -- will be replaced by a copy of the original expression (see
6986 -- Exp_Ch2.Expand_Renaming). Otherwise the temporary must be
6987 -- elaborated by gigi, and is of course not to be replaced in-line
6988 -- by the expression it renames, which would defeat the purpose of
6989 -- removing the side-effect.
6991 if Nkind_In
(Exp
, N_Selected_Component
, N_Indexed_Component
)
6992 and then Has_Non_Standard_Rep
(Etype
(Prefix
(Exp
)))
6996 Set_Is_Renaming_Of_Object
(Def_Id
, False);
6999 -- Otherwise we generate a reference to the value
7002 -- An expression which is in SPARK mode is considered side effect
7003 -- free if the resulting value is captured by a variable or a
7007 and then Nkind
(Parent
(Exp
)) = N_Object_Declaration
7012 -- Special processing for function calls that return a limited type.
7013 -- We need to build a declaration that will enable build-in-place
7014 -- expansion of the call. This is not done if the context is already
7015 -- an object declaration, to prevent infinite recursion.
7017 -- This is relevant only in Ada 2005 mode. In Ada 95 programs we have
7018 -- to accommodate functions returning limited objects by reference.
7020 if Ada_Version
>= Ada_2005
7021 and then Nkind
(Exp
) = N_Function_Call
7022 and then Is_Immutably_Limited_Type
(Etype
(Exp
))
7023 and then Nkind
(Parent
(Exp
)) /= N_Object_Declaration
7026 Obj
: constant Entity_Id
:= Make_Temporary
(Loc
, 'F', Exp
);
7031 Make_Object_Declaration
(Loc
,
7032 Defining_Identifier
=> Obj
,
7033 Object_Definition
=> New_Occurrence_Of
(Exp_Type
, Loc
),
7034 Expression
=> Relocate_Node
(Exp
));
7036 Insert_Action
(Exp
, Decl
);
7037 Set_Etype
(Obj
, Exp_Type
);
7038 Rewrite
(Exp
, New_Occurrence_Of
(Obj
, Loc
));
7043 Def_Id
:= Make_Temporary
(Loc
, 'R', Exp
);
7044 Set_Etype
(Def_Id
, Exp_Type
);
7046 -- The regular expansion of functions with side effects involves the
7047 -- generation of an access type to capture the return value found on
7048 -- the secondary stack. Since SPARK (and why) cannot process access
7049 -- types, use a different approach which ignores the secondary stack
7050 -- and "copies" the returned object.
7053 Res
:= New_Reference_To
(Def_Id
, Loc
);
7054 Ref_Type
:= Exp_Type
;
7056 -- Regular expansion utilizing an access type and 'reference
7060 Make_Explicit_Dereference
(Loc
,
7061 Prefix
=> New_Reference_To
(Def_Id
, Loc
));
7064 -- type Ann is access all <Exp_Type>;
7066 Ref_Type
:= Make_Temporary
(Loc
, 'A');
7069 Make_Full_Type_Declaration
(Loc
,
7070 Defining_Identifier
=> Ref_Type
,
7072 Make_Access_To_Object_Definition
(Loc
,
7073 All_Present
=> True,
7074 Subtype_Indication
=>
7075 New_Reference_To
(Exp_Type
, Loc
)));
7077 Insert_Action
(Exp
, Ptr_Typ_Decl
);
7081 if Nkind
(E
) = N_Explicit_Dereference
then
7082 New_Exp
:= Relocate_Node
(Prefix
(E
));
7084 E
:= Relocate_Node
(E
);
7086 -- Do not generate a 'reference in SPARK mode since the access
7087 -- type is not created in the first place.
7092 -- Otherwise generate reference, marking the value as non-null
7093 -- since we know it cannot be null and we don't want a check.
7096 New_Exp
:= Make_Reference
(Loc
, E
);
7097 Set_Is_Known_Non_Null
(Def_Id
);
7101 if Is_Delayed_Aggregate
(E
) then
7103 -- The expansion of nested aggregates is delayed until the
7104 -- enclosing aggregate is expanded. As aggregates are often
7105 -- qualified, the predicate applies to qualified expressions as
7106 -- well, indicating that the enclosing aggregate has not been
7107 -- expanded yet. At this point the aggregate is part of a
7108 -- stand-alone declaration, and must be fully expanded.
7110 if Nkind
(E
) = N_Qualified_Expression
then
7111 Set_Expansion_Delayed
(Expression
(E
), False);
7112 Set_Analyzed
(Expression
(E
), False);
7114 Set_Expansion_Delayed
(E
, False);
7117 Set_Analyzed
(E
, False);
7121 Make_Object_Declaration
(Loc
,
7122 Defining_Identifier
=> Def_Id
,
7123 Object_Definition
=> New_Reference_To
(Ref_Type
, Loc
),
7124 Constant_Present
=> True,
7125 Expression
=> New_Exp
));
7128 -- Preserve the Assignment_OK flag in all copies, since at least one
7129 -- copy may be used in a context where this flag must be set (otherwise
7130 -- why would the flag be set in the first place).
7132 Set_Assignment_OK
(Res
, Assignment_OK
(Exp
));
7134 -- Finally rewrite the original expression and we are done
7137 Analyze_And_Resolve
(Exp
, Exp_Type
);
7140 Scope_Suppress
:= Svg_Suppress
;
7141 end Remove_Side_Effects
;
7143 ---------------------------
7144 -- Represented_As_Scalar --
7145 ---------------------------
7147 function Represented_As_Scalar
(T
: Entity_Id
) return Boolean is
7148 UT
: constant Entity_Id
:= Underlying_Type
(T
);
7150 return Is_Scalar_Type
(UT
)
7151 or else (Is_Bit_Packed_Array
(UT
)
7152 and then Is_Scalar_Type
(Packed_Array_Type
(UT
)));
7153 end Represented_As_Scalar
;
7155 ------------------------------
7156 -- Requires_Cleanup_Actions --
7157 ------------------------------
7159 function Requires_Cleanup_Actions
7161 Lib_Level
: Boolean) return Boolean
7163 At_Lib_Level
: constant Boolean :=
7165 and then Nkind_In
(N
, N_Package_Body
,
7166 N_Package_Specification
);
7167 -- N is at the library level if the top-most context is a package and
7168 -- the path taken to reach N does not inlcude non-package constructs.
7172 when N_Accept_Statement |
7180 Requires_Cleanup_Actions
(Declarations
(N
), At_Lib_Level
, True)
7182 (Present
(Handled_Statement_Sequence
(N
))
7184 Requires_Cleanup_Actions
7185 (Statements
(Handled_Statement_Sequence
(N
)),
7186 At_Lib_Level
, True));
7188 when N_Package_Specification
=>
7190 Requires_Cleanup_Actions
7191 (Visible_Declarations
(N
), At_Lib_Level
, True)
7193 Requires_Cleanup_Actions
7194 (Private_Declarations
(N
), At_Lib_Level
, True);
7199 end Requires_Cleanup_Actions
;
7201 ------------------------------
7202 -- Requires_Cleanup_Actions --
7203 ------------------------------
7205 function Requires_Cleanup_Actions
7207 Lib_Level
: Boolean;
7208 Nested_Constructs
: Boolean) return Boolean
7213 Obj_Typ
: Entity_Id
;
7214 Pack_Id
: Entity_Id
;
7219 or else Is_Empty_List
(L
)
7225 while Present
(Decl
) loop
7227 -- Library-level tagged types
7229 if Nkind
(Decl
) = N_Full_Type_Declaration
then
7230 Typ
:= Defining_Identifier
(Decl
);
7232 if Is_Tagged_Type
(Typ
)
7233 and then Is_Library_Level_Entity
(Typ
)
7234 and then Convention
(Typ
) = Convention_Ada
7235 and then Present
(Access_Disp_Table
(Typ
))
7236 and then RTE_Available
(RE_Unregister_Tag
)
7237 and then not No_Run_Time_Mode
7238 and then not Is_Abstract_Type
(Typ
)
7243 -- Regular object declarations
7245 elsif Nkind
(Decl
) = N_Object_Declaration
then
7246 Obj_Id
:= Defining_Identifier
(Decl
);
7247 Obj_Typ
:= Base_Type
(Etype
(Obj_Id
));
7248 Expr
:= Expression
(Decl
);
7250 -- Bypass any form of processing for objects which have their
7251 -- finalization disabled. This applies only to objects at the
7254 if Lib_Level
and then Finalize_Storage_Only
(Obj_Typ
) then
7257 -- Transient variables are treated separately in order to minimize
7258 -- the size of the generated code. See Exp_Ch7.Process_Transient_
7261 elsif Is_Processed_Transient
(Obj_Id
) then
7264 -- The object is of the form:
7265 -- Obj : Typ [:= Expr];
7267 -- Do not process the incomplete view of a deferred constant. Do
7268 -- not consider tag-to-class-wide conversions.
7270 elsif not Is_Imported
(Obj_Id
)
7271 and then Needs_Finalization
(Obj_Typ
)
7272 and then not (Ekind
(Obj_Id
) = E_Constant
7273 and then not Has_Completion
(Obj_Id
))
7274 and then not Is_Tag_To_Class_Wide_Conversion
(Obj_Id
)
7278 -- The object is of the form:
7279 -- Obj : Access_Typ := Non_BIP_Function_Call'reference;
7281 -- Obj : Access_Typ :=
7282 -- BIP_Function_Call (BIPalloc => 2, ...)'reference;
7284 elsif Is_Access_Type
(Obj_Typ
)
7285 and then Needs_Finalization
7286 (Available_View
(Designated_Type
(Obj_Typ
)))
7287 and then Present
(Expr
)
7289 (Is_Secondary_Stack_BIP_Func_Call
(Expr
)
7291 (Is_Non_BIP_Func_Call
(Expr
)
7292 and then not Is_Related_To_Func_Return
(Obj_Id
)))
7296 -- Processing for "hook" objects generated for controlled
7297 -- transients declared inside an Expression_With_Actions.
7299 elsif Is_Access_Type
(Obj_Typ
)
7300 and then Present
(Status_Flag_Or_Transient_Decl
(Obj_Id
))
7301 and then Nkind
(Status_Flag_Or_Transient_Decl
(Obj_Id
)) =
7302 N_Object_Declaration
7303 and then Is_Finalizable_Transient
7304 (Status_Flag_Or_Transient_Decl
(Obj_Id
), Decl
)
7308 -- Processing for intermediate results of if expressions where
7309 -- one of the alternatives uses a controlled function call.
7311 elsif Is_Access_Type
(Obj_Typ
)
7312 and then Present
(Status_Flag_Or_Transient_Decl
(Obj_Id
))
7313 and then Nkind
(Status_Flag_Or_Transient_Decl
(Obj_Id
)) =
7314 N_Defining_Identifier
7315 and then Present
(Expr
)
7316 and then Nkind
(Expr
) = N_Null
7320 -- Simple protected objects which use type System.Tasking.
7321 -- Protected_Objects.Protection to manage their locks should be
7322 -- treated as controlled since they require manual cleanup.
7324 elsif Ekind
(Obj_Id
) = E_Variable
7326 (Is_Simple_Protected_Type
(Obj_Typ
)
7327 or else Has_Simple_Protected_Object
(Obj_Typ
))
7332 -- Specific cases of object renamings
7334 elsif Nkind
(Decl
) = N_Object_Renaming_Declaration
then
7335 Obj_Id
:= Defining_Identifier
(Decl
);
7336 Obj_Typ
:= Base_Type
(Etype
(Obj_Id
));
7338 -- Bypass any form of processing for objects which have their
7339 -- finalization disabled. This applies only to objects at the
7342 if Lib_Level
and then Finalize_Storage_Only
(Obj_Typ
) then
7345 -- Return object of a build-in-place function. This case is
7346 -- recognized and marked by the expansion of an extended return
7347 -- statement (see Expand_N_Extended_Return_Statement).
7349 elsif Needs_Finalization
(Obj_Typ
)
7350 and then Is_Return_Object
(Obj_Id
)
7351 and then Present
(Status_Flag_Or_Transient_Decl
(Obj_Id
))
7355 -- Detect a case where a source object has been initialized by
7356 -- a controlled function call or another object which was later
7357 -- rewritten as a class-wide conversion of Ada.Tags.Displace.
7359 -- Obj1 : CW_Type := Src_Obj;
7360 -- Obj2 : CW_Type := Function_Call (...);
7362 -- Obj1 : CW_Type renames (... Ada.Tags.Displace (Src_Obj));
7363 -- Tmp : ... := Function_Call (...)'reference;
7364 -- Obj2 : CW_Type renames (... Ada.Tags.Displace (Tmp));
7366 elsif Is_Displacement_Of_Object_Or_Function_Result
(Obj_Id
) then
7370 -- Inspect the freeze node of an access-to-controlled type and look
7371 -- for a delayed finalization master. This case arises when the
7372 -- freeze actions are inserted at a later time than the expansion of
7373 -- the context. Since Build_Finalizer is never called on a single
7374 -- construct twice, the master will be ultimately left out and never
7375 -- finalized. This is also needed for freeze actions of designated
7376 -- types themselves, since in some cases the finalization master is
7377 -- associated with a designated type's freeze node rather than that
7378 -- of the access type (see handling for freeze actions in
7379 -- Build_Finalization_Master).
7381 elsif Nkind
(Decl
) = N_Freeze_Entity
7382 and then Present
(Actions
(Decl
))
7384 Typ
:= Entity
(Decl
);
7386 if ((Is_Access_Type
(Typ
)
7387 and then not Is_Access_Subprogram_Type
(Typ
)
7388 and then Needs_Finalization
7389 (Available_View
(Designated_Type
(Typ
))))
7392 and then Needs_Finalization
(Typ
)))
7393 and then Requires_Cleanup_Actions
7394 (Actions
(Decl
), Lib_Level
, Nested_Constructs
)
7399 -- Nested package declarations
7401 elsif Nested_Constructs
7402 and then Nkind
(Decl
) = N_Package_Declaration
7404 Pack_Id
:= Defining_Unit_Name
(Specification
(Decl
));
7406 if Nkind
(Pack_Id
) = N_Defining_Program_Unit_Name
then
7407 Pack_Id
:= Defining_Identifier
(Pack_Id
);
7410 if Ekind
(Pack_Id
) /= E_Generic_Package
7412 Requires_Cleanup_Actions
(Specification
(Decl
), Lib_Level
)
7417 -- Nested package bodies
7419 elsif Nested_Constructs
and then Nkind
(Decl
) = N_Package_Body
then
7420 Pack_Id
:= Corresponding_Spec
(Decl
);
7422 if Ekind
(Pack_Id
) /= E_Generic_Package
7423 and then Requires_Cleanup_Actions
(Decl
, Lib_Level
)
7433 end Requires_Cleanup_Actions
;
7435 ------------------------------------
7436 -- Safe_Unchecked_Type_Conversion --
7437 ------------------------------------
7439 -- Note: this function knows quite a bit about the exact requirements of
7440 -- Gigi with respect to unchecked type conversions, and its code must be
7441 -- coordinated with any changes in Gigi in this area.
7443 -- The above requirements should be documented in Sinfo ???
7445 function Safe_Unchecked_Type_Conversion
(Exp
: Node_Id
) return Boolean is
7450 Pexp
: constant Node_Id
:= Parent
(Exp
);
7453 -- If the expression is the RHS of an assignment or object declaration
7454 -- we are always OK because there will always be a target.
7456 -- Object renaming declarations, (generated for view conversions of
7457 -- actuals in inlined calls), like object declarations, provide an
7458 -- explicit type, and are safe as well.
7460 if (Nkind
(Pexp
) = N_Assignment_Statement
7461 and then Expression
(Pexp
) = Exp
)
7462 or else Nkind_In
(Pexp
, N_Object_Declaration
,
7463 N_Object_Renaming_Declaration
)
7467 -- If the expression is the prefix of an N_Selected_Component we should
7468 -- also be OK because GCC knows to look inside the conversion except if
7469 -- the type is discriminated. We assume that we are OK anyway if the
7470 -- type is not set yet or if it is controlled since we can't afford to
7471 -- introduce a temporary in this case.
7473 elsif Nkind
(Pexp
) = N_Selected_Component
7474 and then Prefix
(Pexp
) = Exp
7476 if No
(Etype
(Pexp
)) then
7480 not Has_Discriminants
(Etype
(Pexp
))
7481 or else Is_Constrained
(Etype
(Pexp
));
7485 -- Set the output type, this comes from Etype if it is set, otherwise we
7486 -- take it from the subtype mark, which we assume was already fully
7489 if Present
(Etype
(Exp
)) then
7490 Otyp
:= Etype
(Exp
);
7492 Otyp
:= Entity
(Subtype_Mark
(Exp
));
7495 -- The input type always comes from the expression, and we assume
7496 -- this is indeed always analyzed, so we can simply get the Etype.
7498 Ityp
:= Etype
(Expression
(Exp
));
7500 -- Initialize alignments to unknown so far
7505 -- Replace a concurrent type by its corresponding record type and each
7506 -- type by its underlying type and do the tests on those. The original
7507 -- type may be a private type whose completion is a concurrent type, so
7508 -- find the underlying type first.
7510 if Present
(Underlying_Type
(Otyp
)) then
7511 Otyp
:= Underlying_Type
(Otyp
);
7514 if Present
(Underlying_Type
(Ityp
)) then
7515 Ityp
:= Underlying_Type
(Ityp
);
7518 if Is_Concurrent_Type
(Otyp
) then
7519 Otyp
:= Corresponding_Record_Type
(Otyp
);
7522 if Is_Concurrent_Type
(Ityp
) then
7523 Ityp
:= Corresponding_Record_Type
(Ityp
);
7526 -- If the base types are the same, we know there is no problem since
7527 -- this conversion will be a noop.
7529 if Implementation_Base_Type
(Otyp
) = Implementation_Base_Type
(Ityp
) then
7532 -- Same if this is an upwards conversion of an untagged type, and there
7533 -- are no constraints involved (could be more general???)
7535 elsif Etype
(Ityp
) = Otyp
7536 and then not Is_Tagged_Type
(Ityp
)
7537 and then not Has_Discriminants
(Ityp
)
7538 and then No
(First_Rep_Item
(Base_Type
(Ityp
)))
7542 -- If the expression has an access type (object or subprogram) we assume
7543 -- that the conversion is safe, because the size of the target is safe,
7544 -- even if it is a record (which might be treated as having unknown size
7547 elsif Is_Access_Type
(Ityp
) then
7550 -- If the size of output type is known at compile time, there is never
7551 -- a problem. Note that unconstrained records are considered to be of
7552 -- known size, but we can't consider them that way here, because we are
7553 -- talking about the actual size of the object.
7555 -- We also make sure that in addition to the size being known, we do not
7556 -- have a case which might generate an embarrassingly large temp in
7557 -- stack checking mode.
7559 elsif Size_Known_At_Compile_Time
(Otyp
)
7561 (not Stack_Checking_Enabled
7562 or else not May_Generate_Large_Temp
(Otyp
))
7563 and then not (Is_Record_Type
(Otyp
) and then not Is_Constrained
(Otyp
))
7567 -- If either type is tagged, then we know the alignment is OK so
7568 -- Gigi will be able to use pointer punning.
7570 elsif Is_Tagged_Type
(Otyp
) or else Is_Tagged_Type
(Ityp
) then
7573 -- If either type is a limited record type, we cannot do a copy, so say
7574 -- safe since there's nothing else we can do.
7576 elsif Is_Limited_Record
(Otyp
) or else Is_Limited_Record
(Ityp
) then
7579 -- Conversions to and from packed array types are always ignored and
7582 elsif Is_Packed_Array_Type
(Otyp
)
7583 or else Is_Packed_Array_Type
(Ityp
)
7588 -- The only other cases known to be safe is if the input type's
7589 -- alignment is known to be at least the maximum alignment for the
7590 -- target or if both alignments are known and the output type's
7591 -- alignment is no stricter than the input's. We can use the component
7592 -- type alignement for an array if a type is an unpacked array type.
7594 if Present
(Alignment_Clause
(Otyp
)) then
7595 Oalign
:= Expr_Value
(Expression
(Alignment_Clause
(Otyp
)));
7597 elsif Is_Array_Type
(Otyp
)
7598 and then Present
(Alignment_Clause
(Component_Type
(Otyp
)))
7600 Oalign
:= Expr_Value
(Expression
(Alignment_Clause
7601 (Component_Type
(Otyp
))));
7604 if Present
(Alignment_Clause
(Ityp
)) then
7605 Ialign
:= Expr_Value
(Expression
(Alignment_Clause
(Ityp
)));
7607 elsif Is_Array_Type
(Ityp
)
7608 and then Present
(Alignment_Clause
(Component_Type
(Ityp
)))
7610 Ialign
:= Expr_Value
(Expression
(Alignment_Clause
7611 (Component_Type
(Ityp
))));
7614 if Ialign
/= No_Uint
and then Ialign
> Maximum_Alignment
then
7617 elsif Ialign
/= No_Uint
and then Oalign
/= No_Uint
7618 and then Ialign
<= Oalign
7622 -- Otherwise, Gigi cannot handle this and we must make a temporary
7627 end Safe_Unchecked_Type_Conversion
;
7629 ---------------------------------
7630 -- Set_Current_Value_Condition --
7631 ---------------------------------
7633 -- Note: the implementation of this procedure is very closely tied to the
7634 -- implementation of Get_Current_Value_Condition. Here we set required
7635 -- Current_Value fields, and in Get_Current_Value_Condition, we interpret
7636 -- them, so they must have a consistent view.
7638 procedure Set_Current_Value_Condition
(Cnode
: Node_Id
) is
7640 procedure Set_Entity_Current_Value
(N
: Node_Id
);
7641 -- If N is an entity reference, where the entity is of an appropriate
7642 -- kind, then set the current value of this entity to Cnode, unless
7643 -- there is already a definite value set there.
7645 procedure Set_Expression_Current_Value
(N
: Node_Id
);
7646 -- If N is of an appropriate form, sets an appropriate entry in current
7647 -- value fields of relevant entities. Multiple entities can be affected
7648 -- in the case of an AND or AND THEN.
7650 ------------------------------
7651 -- Set_Entity_Current_Value --
7652 ------------------------------
7654 procedure Set_Entity_Current_Value
(N
: Node_Id
) is
7656 if Is_Entity_Name
(N
) then
7658 Ent
: constant Entity_Id
:= Entity
(N
);
7661 -- Don't capture if not safe to do so
7663 if not Safe_To_Capture_Value
(N
, Ent
, Cond
=> True) then
7667 -- Here we have a case where the Current_Value field may need
7668 -- to be set. We set it if it is not already set to a compile
7669 -- time expression value.
7671 -- Note that this represents a decision that one condition
7672 -- blots out another previous one. That's certainly right if
7673 -- they occur at the same level. If the second one is nested,
7674 -- then the decision is neither right nor wrong (it would be
7675 -- equally OK to leave the outer one in place, or take the new
7676 -- inner one. Really we should record both, but our data
7677 -- structures are not that elaborate.
7679 if Nkind
(Current_Value
(Ent
)) not in N_Subexpr
then
7680 Set_Current_Value
(Ent
, Cnode
);
7684 end Set_Entity_Current_Value
;
7686 ----------------------------------
7687 -- Set_Expression_Current_Value --
7688 ----------------------------------
7690 procedure Set_Expression_Current_Value
(N
: Node_Id
) is
7696 -- Loop to deal with (ignore for now) any NOT operators present. The
7697 -- presence of NOT operators will be handled properly when we call
7698 -- Get_Current_Value_Condition.
7700 while Nkind
(Cond
) = N_Op_Not
loop
7701 Cond
:= Right_Opnd
(Cond
);
7704 -- For an AND or AND THEN, recursively process operands
7706 if Nkind
(Cond
) = N_Op_And
or else Nkind
(Cond
) = N_And_Then
then
7707 Set_Expression_Current_Value
(Left_Opnd
(Cond
));
7708 Set_Expression_Current_Value
(Right_Opnd
(Cond
));
7712 -- Check possible relational operator
7714 if Nkind
(Cond
) in N_Op_Compare
then
7715 if Compile_Time_Known_Value
(Right_Opnd
(Cond
)) then
7716 Set_Entity_Current_Value
(Left_Opnd
(Cond
));
7717 elsif Compile_Time_Known_Value
(Left_Opnd
(Cond
)) then
7718 Set_Entity_Current_Value
(Right_Opnd
(Cond
));
7721 -- Check possible boolean variable reference
7724 Set_Entity_Current_Value
(Cond
);
7726 end Set_Expression_Current_Value
;
7728 -- Start of processing for Set_Current_Value_Condition
7731 Set_Expression_Current_Value
(Condition
(Cnode
));
7732 end Set_Current_Value_Condition
;
7734 --------------------------
7735 -- Set_Elaboration_Flag --
7736 --------------------------
7738 procedure Set_Elaboration_Flag
(N
: Node_Id
; Spec_Id
: Entity_Id
) is
7739 Loc
: constant Source_Ptr
:= Sloc
(N
);
7740 Ent
: constant Entity_Id
:= Elaboration_Entity
(Spec_Id
);
7744 if Present
(Ent
) then
7746 -- Nothing to do if at the compilation unit level, because in this
7747 -- case the flag is set by the binder generated elaboration routine.
7749 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
7752 -- Here we do need to generate an assignment statement
7755 Check_Restriction
(No_Elaboration_Code
, N
);
7757 Make_Assignment_Statement
(Loc
,
7758 Name
=> New_Occurrence_Of
(Ent
, Loc
),
7759 Expression
=> Make_Integer_Literal
(Loc
, Uint_1
));
7761 if Nkind
(Parent
(N
)) = N_Subunit
then
7762 Insert_After
(Corresponding_Stub
(Parent
(N
)), Asn
);
7764 Insert_After
(N
, Asn
);
7769 -- Kill current value indication. This is necessary because the
7770 -- tests of this flag are inserted out of sequence and must not
7771 -- pick up bogus indications of the wrong constant value.
7773 Set_Current_Value
(Ent
, Empty
);
7776 end Set_Elaboration_Flag
;
7778 ----------------------------
7779 -- Set_Renamed_Subprogram --
7780 ----------------------------
7782 procedure Set_Renamed_Subprogram
(N
: Node_Id
; E
: Entity_Id
) is
7784 -- If input node is an identifier, we can just reset it
7786 if Nkind
(N
) = N_Identifier
then
7787 Set_Chars
(N
, Chars
(E
));
7790 -- Otherwise we have to do a rewrite, preserving Comes_From_Source
7794 CS
: constant Boolean := Comes_From_Source
(N
);
7796 Rewrite
(N
, Make_Identifier
(Sloc
(N
), Chars
(E
)));
7798 Set_Comes_From_Source
(N
, CS
);
7799 Set_Analyzed
(N
, True);
7802 end Set_Renamed_Subprogram
;
7804 ----------------------------------
7805 -- Silly_Boolean_Array_Not_Test --
7806 ----------------------------------
7808 -- This procedure implements an odd and silly test. We explicitly check
7809 -- for the case where the 'First of the component type is equal to the
7810 -- 'Last of this component type, and if this is the case, we make sure
7811 -- that constraint error is raised. The reason is that the NOT is bound
7812 -- to cause CE in this case, and we will not otherwise catch it.
7814 -- No such check is required for AND and OR, since for both these cases
7815 -- False op False = False, and True op True = True. For the XOR case,
7816 -- see Silly_Boolean_Array_Xor_Test.
7818 -- Believe it or not, this was reported as a bug. Note that nearly always,
7819 -- the test will evaluate statically to False, so the code will be
7820 -- statically removed, and no extra overhead caused.
7822 procedure Silly_Boolean_Array_Not_Test
(N
: Node_Id
; T
: Entity_Id
) is
7823 Loc
: constant Source_Ptr
:= Sloc
(N
);
7824 CT
: constant Entity_Id
:= Component_Type
(T
);
7827 -- The check we install is
7829 -- constraint_error when
7830 -- component_type'first = component_type'last
7831 -- and then array_type'Length /= 0)
7833 -- We need the last guard because we don't want to raise CE for empty
7834 -- arrays since no out of range values result. (Empty arrays with a
7835 -- component type of True .. True -- very useful -- even the ACATS
7836 -- does not test that marginal case!)
7839 Make_Raise_Constraint_Error
(Loc
,
7845 Make_Attribute_Reference
(Loc
,
7846 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
7847 Attribute_Name
=> Name_First
),
7850 Make_Attribute_Reference
(Loc
,
7851 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
7852 Attribute_Name
=> Name_Last
)),
7854 Right_Opnd
=> Make_Non_Empty_Check
(Loc
, Right_Opnd
(N
))),
7855 Reason
=> CE_Range_Check_Failed
));
7856 end Silly_Boolean_Array_Not_Test
;
7858 ----------------------------------
7859 -- Silly_Boolean_Array_Xor_Test --
7860 ----------------------------------
7862 -- This procedure implements an odd and silly test. We explicitly check
7863 -- for the XOR case where the component type is True .. True, since this
7864 -- will raise constraint error. A special check is required since CE
7865 -- will not be generated otherwise (cf Expand_Packed_Not).
7867 -- No such check is required for AND and OR, since for both these cases
7868 -- False op False = False, and True op True = True, and no check is
7869 -- required for the case of False .. False, since False xor False = False.
7870 -- See also Silly_Boolean_Array_Not_Test
7872 procedure Silly_Boolean_Array_Xor_Test
(N
: Node_Id
; T
: Entity_Id
) is
7873 Loc
: constant Source_Ptr
:= Sloc
(N
);
7874 CT
: constant Entity_Id
:= Component_Type
(T
);
7877 -- The check we install is
7879 -- constraint_error when
7880 -- Boolean (component_type'First)
7881 -- and then Boolean (component_type'Last)
7882 -- and then array_type'Length /= 0)
7884 -- We need the last guard because we don't want to raise CE for empty
7885 -- arrays since no out of range values result (Empty arrays with a
7886 -- component type of True .. True -- very useful -- even the ACATS
7887 -- does not test that marginal case!).
7890 Make_Raise_Constraint_Error
(Loc
,
7896 Convert_To
(Standard_Boolean
,
7897 Make_Attribute_Reference
(Loc
,
7898 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
7899 Attribute_Name
=> Name_First
)),
7902 Convert_To
(Standard_Boolean
,
7903 Make_Attribute_Reference
(Loc
,
7904 Prefix
=> New_Occurrence_Of
(CT
, Loc
),
7905 Attribute_Name
=> Name_Last
))),
7907 Right_Opnd
=> Make_Non_Empty_Check
(Loc
, Right_Opnd
(N
))),
7908 Reason
=> CE_Range_Check_Failed
));
7909 end Silly_Boolean_Array_Xor_Test
;
7911 --------------------------
7912 -- Target_Has_Fixed_Ops --
7913 --------------------------
7915 Integer_Sized_Small
: Ureal
;
7916 -- Set to 2.0 ** -(Integer'Size - 1) the first time that this function is
7917 -- called (we don't want to compute it more than once!)
7919 Long_Integer_Sized_Small
: Ureal
;
7920 -- Set to 2.0 ** -(Long_Integer'Size - 1) the first time that this function
7921 -- is called (we don't want to compute it more than once)
7923 First_Time_For_THFO
: Boolean := True;
7924 -- Set to False after first call (if Fractional_Fixed_Ops_On_Target)
7926 function Target_Has_Fixed_Ops
7927 (Left_Typ
: Entity_Id
;
7928 Right_Typ
: Entity_Id
;
7929 Result_Typ
: Entity_Id
) return Boolean
7931 function Is_Fractional_Type
(Typ
: Entity_Id
) return Boolean;
7932 -- Return True if the given type is a fixed-point type with a small
7933 -- value equal to 2 ** (-(T'Object_Size - 1)) and whose values have
7934 -- an absolute value less than 1.0. This is currently limited to
7935 -- fixed-point types that map to Integer or Long_Integer.
7937 ------------------------
7938 -- Is_Fractional_Type --
7939 ------------------------
7941 function Is_Fractional_Type
(Typ
: Entity_Id
) return Boolean is
7943 if Esize
(Typ
) = Standard_Integer_Size
then
7944 return Small_Value
(Typ
) = Integer_Sized_Small
;
7946 elsif Esize
(Typ
) = Standard_Long_Integer_Size
then
7947 return Small_Value
(Typ
) = Long_Integer_Sized_Small
;
7952 end Is_Fractional_Type
;
7954 -- Start of processing for Target_Has_Fixed_Ops
7957 -- Return False if Fractional_Fixed_Ops_On_Target is false
7959 if not Fractional_Fixed_Ops_On_Target
then
7963 -- Here the target has Fractional_Fixed_Ops, if first time, compute
7964 -- standard constants used by Is_Fractional_Type.
7966 if First_Time_For_THFO
then
7967 First_Time_For_THFO
:= False;
7969 Integer_Sized_Small
:=
7972 Den
=> UI_From_Int
(Standard_Integer_Size
- 1),
7975 Long_Integer_Sized_Small
:=
7978 Den
=> UI_From_Int
(Standard_Long_Integer_Size
- 1),
7982 -- Return True if target supports fixed-by-fixed multiply/divide for
7983 -- fractional fixed-point types (see Is_Fractional_Type) and the operand
7984 -- and result types are equivalent fractional types.
7986 return Is_Fractional_Type
(Base_Type
(Left_Typ
))
7987 and then Is_Fractional_Type
(Base_Type
(Right_Typ
))
7988 and then Is_Fractional_Type
(Base_Type
(Result_Typ
))
7989 and then Esize
(Left_Typ
) = Esize
(Right_Typ
)
7990 and then Esize
(Left_Typ
) = Esize
(Result_Typ
);
7991 end Target_Has_Fixed_Ops
;
7993 ------------------------------------------
7994 -- Type_May_Have_Bit_Aligned_Components --
7995 ------------------------------------------
7997 function Type_May_Have_Bit_Aligned_Components
7998 (Typ
: Entity_Id
) return Boolean
8001 -- Array type, check component type
8003 if Is_Array_Type
(Typ
) then
8005 Type_May_Have_Bit_Aligned_Components
(Component_Type
(Typ
));
8007 -- Record type, check components
8009 elsif Is_Record_Type
(Typ
) then
8014 E
:= First_Component_Or_Discriminant
(Typ
);
8015 while Present
(E
) loop
8016 if Component_May_Be_Bit_Aligned
(E
)
8017 or else Type_May_Have_Bit_Aligned_Components
(Etype
(E
))
8022 Next_Component_Or_Discriminant
(E
);
8028 -- Type other than array or record is always OK
8033 end Type_May_Have_Bit_Aligned_Components
;
8035 ----------------------------------
8036 -- Within_Case_Or_If_Expression --
8037 ----------------------------------
8039 function Within_Case_Or_If_Expression
(N
: Node_Id
) return Boolean is
8043 -- Locate an enclosing case or if expression. Note that these constructs
8044 -- can be expanded into Expression_With_Actions, hence the test of the
8048 while Present
(Par
) loop
8049 if Nkind_In
(Original_Node
(Par
), N_Case_Expression
,
8054 -- Prevent the search from going too far
8056 elsif Is_Body_Or_Package_Declaration
(Par
) then
8060 Par
:= Parent
(Par
);
8064 end Within_Case_Or_If_Expression
;
8066 ----------------------------
8067 -- Wrap_Cleanup_Procedure --
8068 ----------------------------
8070 procedure Wrap_Cleanup_Procedure
(N
: Node_Id
) is
8071 Loc
: constant Source_Ptr
:= Sloc
(N
);
8072 Stseq
: constant Node_Id
:= Handled_Statement_Sequence
(N
);
8073 Stmts
: constant List_Id
:= Statements
(Stseq
);
8076 if Abort_Allowed
then
8077 Prepend_To
(Stmts
, Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
8078 Append_To
(Stmts
, Build_Runtime_Call
(Loc
, RE_Abort_Undefer
));
8080 end Wrap_Cleanup_Procedure
;