1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Checks
; use Checks
;
28 with Debug
; use Debug
;
29 with Einfo
; use Einfo
;
30 with Elists
; use Elists
;
31 with Errout
; use Errout
;
32 with Exp_Aggr
; use Exp_Aggr
;
33 with Exp_Atag
; use Exp_Atag
;
34 with Exp_Ch3
; use Exp_Ch3
;
35 with Exp_Ch6
; use Exp_Ch6
;
36 with Exp_Ch7
; use Exp_Ch7
;
37 with Exp_Ch9
; use Exp_Ch9
;
38 with Exp_Disp
; use Exp_Disp
;
39 with Exp_Fixd
; use Exp_Fixd
;
40 with Exp_Pakd
; use Exp_Pakd
;
41 with Exp_Tss
; use Exp_Tss
;
42 with Exp_Util
; use Exp_Util
;
43 with Exp_VFpt
; use Exp_VFpt
;
44 with Freeze
; use Freeze
;
45 with Inline
; use Inline
;
46 with Namet
; use Namet
;
47 with Nlists
; use Nlists
;
48 with Nmake
; use Nmake
;
50 with Restrict
; use Restrict
;
51 with Rident
; use Rident
;
52 with Rtsfind
; use Rtsfind
;
54 with Sem_Aux
; use Sem_Aux
;
55 with Sem_Cat
; use Sem_Cat
;
56 with Sem_Ch3
; use Sem_Ch3
;
57 with Sem_Ch8
; use Sem_Ch8
;
58 with Sem_Ch13
; use Sem_Ch13
;
59 with Sem_Eval
; use Sem_Eval
;
60 with Sem_Res
; use Sem_Res
;
61 with Sem_Type
; use Sem_Type
;
62 with Sem_Util
; use Sem_Util
;
63 with Sem_Warn
; use Sem_Warn
;
64 with Sinfo
; use Sinfo
;
65 with Snames
; use Snames
;
66 with Stand
; use Stand
;
67 with Targparm
; use Targparm
;
68 with Tbuild
; use Tbuild
;
69 with Ttypes
; use Ttypes
;
70 with Uintp
; use Uintp
;
71 with Urealp
; use Urealp
;
72 with Validsw
; use Validsw
;
74 package body Exp_Ch4
is
76 -----------------------
77 -- Local Subprograms --
78 -----------------------
80 procedure Binary_Op_Validity_Checks
(N
: Node_Id
);
81 pragma Inline
(Binary_Op_Validity_Checks
);
82 -- Performs validity checks for a binary operator
84 procedure Build_Boolean_Array_Proc_Call
88 -- If a boolean array assignment can be done in place, build call to
89 -- corresponding library procedure.
91 procedure Displace_Allocator_Pointer
(N
: Node_Id
);
92 -- Ada 2005 (AI-251): Subsidiary procedure to Expand_N_Allocator and
93 -- Expand_Allocator_Expression. Allocating class-wide interface objects
94 -- this routine displaces the pointer to the allocated object to reference
95 -- the component referencing the corresponding secondary dispatch table.
97 procedure Expand_Allocator_Expression
(N
: Node_Id
);
98 -- Subsidiary to Expand_N_Allocator, for the case when the expression
99 -- is a qualified expression or an aggregate.
101 procedure Expand_Array_Comparison
(N
: Node_Id
);
102 -- This routine handles expansion of the comparison operators (N_Op_Lt,
103 -- N_Op_Le, N_Op_Gt, N_Op_Ge) when operating on an array type. The basic
104 -- code for these operators is similar, differing only in the details of
105 -- the actual comparison call that is made. Special processing (call a
108 function Expand_Array_Equality
113 Typ
: Entity_Id
) return Node_Id
;
114 -- Expand an array equality into a call to a function implementing this
115 -- equality, and a call to it. Loc is the location for the generated nodes.
116 -- Lhs and Rhs are the array expressions to be compared. Bodies is a list
117 -- on which to attach bodies of local functions that are created in the
118 -- process. It is the responsibility of the caller to insert those bodies
119 -- at the right place. Nod provides the Sloc value for the generated code.
120 -- Normally the types used for the generated equality routine are taken
121 -- from Lhs and Rhs. However, in some situations of generated code, the
122 -- Etype fields of Lhs and Rhs are not set yet. In such cases, Typ supplies
123 -- the type to be used for the formal parameters.
125 procedure Expand_Boolean_Operator
(N
: Node_Id
);
126 -- Common expansion processing for Boolean operators (And, Or, Xor) for the
127 -- case of array type arguments.
129 function Expand_Composite_Equality
134 Bodies
: List_Id
) return Node_Id
;
135 -- Local recursive function used to expand equality for nested composite
136 -- types. Used by Expand_Record/Array_Equality, Bodies is a list on which
137 -- to attach bodies of local functions that are created in the process.
138 -- This is the responsibility of the caller to insert those bodies at the
139 -- right place. Nod provides the Sloc value for generated code. Lhs and Rhs
140 -- are the left and right sides for the comparison, and Typ is the type of
141 -- the arrays to compare.
143 procedure Expand_Concatenate
(Cnode
: Node_Id
; Opnds
: List_Id
);
144 -- Routine to expand concatenation of a sequence of two or more operands
145 -- (in the list Operands) and replace node Cnode with the result of the
146 -- concatenation. The operands can be of any appropriate type, and can
147 -- include both arrays and singleton elements.
149 procedure Fixup_Universal_Fixed_Operation
(N
: Node_Id
);
150 -- N is a N_Op_Divide or N_Op_Multiply node whose result is universal
151 -- fixed. We do not have such a type at runtime, so the purpose of this
152 -- routine is to find the real type by looking up the tree. We also
153 -- determine if the operation must be rounded.
155 function Get_Allocator_Final_List
158 PtrT
: Entity_Id
) return Entity_Id
;
159 -- If the designated type is controlled, build final_list expression for
160 -- created object. If context is an access parameter, create a local access
161 -- type to have a usable finalization list.
163 function Has_Inferable_Discriminants
(N
: Node_Id
) return Boolean;
164 -- Ada 2005 (AI-216): A view of an Unchecked_Union object has inferable
165 -- discriminants if it has a constrained nominal type, unless the object
166 -- is a component of an enclosing Unchecked_Union object that is subject
167 -- to a per-object constraint and the enclosing object lacks inferable
170 -- An expression of an Unchecked_Union type has inferable discriminants
171 -- if it is either a name of an object with inferable discriminants or a
172 -- qualified expression whose subtype mark denotes a constrained subtype.
174 procedure Insert_Dereference_Action
(N
: Node_Id
);
175 -- N is an expression whose type is an access. When the type of the
176 -- associated storage pool is derived from Checked_Pool, generate a
177 -- call to the 'Dereference' primitive operation.
179 function Make_Array_Comparison_Op
181 Nod
: Node_Id
) return Node_Id
;
182 -- Comparisons between arrays are expanded in line. This function produces
183 -- the body of the implementation of (a > b), where a and b are one-
184 -- dimensional arrays of some discrete type. The original node is then
185 -- expanded into the appropriate call to this function. Nod provides the
186 -- Sloc value for the generated code.
188 function Make_Boolean_Array_Op
190 N
: Node_Id
) return Node_Id
;
191 -- Boolean operations on boolean arrays are expanded in line. This function
192 -- produce the body for the node N, which is (a and b), (a or b), or (a xor
193 -- b). It is used only the normal case and not the packed case. The type
194 -- involved, Typ, is the Boolean array type, and the logical operations in
195 -- the body are simple boolean operations. Note that Typ is always a
196 -- constrained type (the caller has ensured this by using
197 -- Convert_To_Actual_Subtype if necessary).
199 procedure Rewrite_Comparison
(N
: Node_Id
);
200 -- If N is the node for a comparison whose outcome can be determined at
201 -- compile time, then the node N can be rewritten with True or False. If
202 -- the outcome cannot be determined at compile time, the call has no
203 -- effect. If N is a type conversion, then this processing is applied to
204 -- its expression. If N is neither comparison nor a type conversion, the
205 -- call has no effect.
207 function Tagged_Membership
(N
: Node_Id
) return Node_Id
;
208 -- Construct the expression corresponding to the tagged membership test.
209 -- Deals with a second operand being (or not) a class-wide type.
211 function Safe_In_Place_Array_Op
214 Op2
: Node_Id
) return Boolean;
215 -- In the context of an assignment, where the right-hand side is a boolean
216 -- operation on arrays, check whether operation can be performed in place.
218 procedure Unary_Op_Validity_Checks
(N
: Node_Id
);
219 pragma Inline
(Unary_Op_Validity_Checks
);
220 -- Performs validity checks for a unary operator
222 -------------------------------
223 -- Binary_Op_Validity_Checks --
224 -------------------------------
226 procedure Binary_Op_Validity_Checks
(N
: Node_Id
) is
228 if Validity_Checks_On
and Validity_Check_Operands
then
229 Ensure_Valid
(Left_Opnd
(N
));
230 Ensure_Valid
(Right_Opnd
(N
));
232 end Binary_Op_Validity_Checks
;
234 ------------------------------------
235 -- Build_Boolean_Array_Proc_Call --
236 ------------------------------------
238 procedure Build_Boolean_Array_Proc_Call
243 Loc
: constant Source_Ptr
:= Sloc
(N
);
244 Kind
: constant Node_Kind
:= Nkind
(Expression
(N
));
245 Target
: constant Node_Id
:=
246 Make_Attribute_Reference
(Loc
,
248 Attribute_Name
=> Name_Address
);
250 Arg1
: constant Node_Id
:= Op1
;
251 Arg2
: Node_Id
:= Op2
;
253 Proc_Name
: Entity_Id
;
256 if Kind
= N_Op_Not
then
257 if Nkind
(Op1
) in N_Binary_Op
then
259 -- Use negated version of the binary operators
261 if Nkind
(Op1
) = N_Op_And
then
262 Proc_Name
:= RTE
(RE_Vector_Nand
);
264 elsif Nkind
(Op1
) = N_Op_Or
then
265 Proc_Name
:= RTE
(RE_Vector_Nor
);
267 else pragma Assert
(Nkind
(Op1
) = N_Op_Xor
);
268 Proc_Name
:= RTE
(RE_Vector_Xor
);
272 Make_Procedure_Call_Statement
(Loc
,
273 Name
=> New_Occurrence_Of
(Proc_Name
, Loc
),
275 Parameter_Associations
=> New_List
(
277 Make_Attribute_Reference
(Loc
,
278 Prefix
=> Left_Opnd
(Op1
),
279 Attribute_Name
=> Name_Address
),
281 Make_Attribute_Reference
(Loc
,
282 Prefix
=> Right_Opnd
(Op1
),
283 Attribute_Name
=> Name_Address
),
285 Make_Attribute_Reference
(Loc
,
286 Prefix
=> Left_Opnd
(Op1
),
287 Attribute_Name
=> Name_Length
)));
290 Proc_Name
:= RTE
(RE_Vector_Not
);
293 Make_Procedure_Call_Statement
(Loc
,
294 Name
=> New_Occurrence_Of
(Proc_Name
, Loc
),
295 Parameter_Associations
=> New_List
(
298 Make_Attribute_Reference
(Loc
,
300 Attribute_Name
=> Name_Address
),
302 Make_Attribute_Reference
(Loc
,
304 Attribute_Name
=> Name_Length
)));
308 -- We use the following equivalences:
310 -- (not X) or (not Y) = not (X and Y) = Nand (X, Y)
311 -- (not X) and (not Y) = not (X or Y) = Nor (X, Y)
312 -- (not X) xor (not Y) = X xor Y
313 -- X xor (not Y) = not (X xor Y) = Nxor (X, Y)
315 if Nkind
(Op1
) = N_Op_Not
then
316 if Kind
= N_Op_And
then
317 Proc_Name
:= RTE
(RE_Vector_Nor
);
319 elsif Kind
= N_Op_Or
then
320 Proc_Name
:= RTE
(RE_Vector_Nand
);
323 Proc_Name
:= RTE
(RE_Vector_Xor
);
327 if Kind
= N_Op_And
then
328 Proc_Name
:= RTE
(RE_Vector_And
);
330 elsif Kind
= N_Op_Or
then
331 Proc_Name
:= RTE
(RE_Vector_Or
);
333 elsif Nkind
(Op2
) = N_Op_Not
then
334 Proc_Name
:= RTE
(RE_Vector_Nxor
);
335 Arg2
:= Right_Opnd
(Op2
);
338 Proc_Name
:= RTE
(RE_Vector_Xor
);
343 Make_Procedure_Call_Statement
(Loc
,
344 Name
=> New_Occurrence_Of
(Proc_Name
, Loc
),
345 Parameter_Associations
=> New_List
(
347 Make_Attribute_Reference
(Loc
,
349 Attribute_Name
=> Name_Address
),
350 Make_Attribute_Reference
(Loc
,
352 Attribute_Name
=> Name_Address
),
353 Make_Attribute_Reference
(Loc
,
355 Attribute_Name
=> Name_Length
)));
358 Rewrite
(N
, Call_Node
);
362 when RE_Not_Available
=>
364 end Build_Boolean_Array_Proc_Call
;
366 --------------------------------
367 -- Displace_Allocator_Pointer --
368 --------------------------------
370 procedure Displace_Allocator_Pointer
(N
: Node_Id
) is
371 Loc
: constant Source_Ptr
:= Sloc
(N
);
372 Orig_Node
: constant Node_Id
:= Original_Node
(N
);
378 -- Do nothing in case of VM targets: the virtual machine will handle
379 -- interfaces directly.
381 if not Tagged_Type_Expansion
then
385 pragma Assert
(Nkind
(N
) = N_Identifier
386 and then Nkind
(Orig_Node
) = N_Allocator
);
388 PtrT
:= Etype
(Orig_Node
);
389 Dtyp
:= Designated_Type
(PtrT
);
390 Etyp
:= Etype
(Expression
(Orig_Node
));
392 if Is_Class_Wide_Type
(Dtyp
)
393 and then Is_Interface
(Dtyp
)
395 -- If the type of the allocator expression is not an interface type
396 -- we can generate code to reference the record component containing
397 -- the pointer to the secondary dispatch table.
399 if not Is_Interface
(Etyp
) then
401 Saved_Typ
: constant Entity_Id
:= Etype
(Orig_Node
);
404 -- 1) Get access to the allocated object
407 Make_Explicit_Dereference
(Loc
,
412 -- 2) Add the conversion to displace the pointer to reference
413 -- the secondary dispatch table.
415 Rewrite
(N
, Convert_To
(Dtyp
, Relocate_Node
(N
)));
416 Analyze_And_Resolve
(N
, Dtyp
);
418 -- 3) The 'access to the secondary dispatch table will be used
419 -- as the value returned by the allocator.
422 Make_Attribute_Reference
(Loc
,
423 Prefix
=> Relocate_Node
(N
),
424 Attribute_Name
=> Name_Access
));
425 Set_Etype
(N
, Saved_Typ
);
429 -- If the type of the allocator expression is an interface type we
430 -- generate a run-time call to displace "this" to reference the
431 -- component containing the pointer to the secondary dispatch table
432 -- or else raise Constraint_Error if the actual object does not
433 -- implement the target interface. This case corresponds with the
434 -- following example:
436 -- function Op (Obj : Iface_1'Class) return access Iface_2'Class is
438 -- return new Iface_2'Class'(Obj);
443 Unchecked_Convert_To
(PtrT
,
444 Make_Function_Call
(Loc
,
445 Name
=> New_Reference_To
(RTE
(RE_Displace
), Loc
),
446 Parameter_Associations
=> New_List
(
447 Unchecked_Convert_To
(RTE
(RE_Address
),
453 (Access_Disp_Table
(Etype
(Base_Type
(Dtyp
))))),
455 Analyze_And_Resolve
(N
, PtrT
);
458 end Displace_Allocator_Pointer
;
460 ---------------------------------
461 -- Expand_Allocator_Expression --
462 ---------------------------------
464 procedure Expand_Allocator_Expression
(N
: Node_Id
) is
465 Loc
: constant Source_Ptr
:= Sloc
(N
);
466 Exp
: constant Node_Id
:= Expression
(Expression
(N
));
467 PtrT
: constant Entity_Id
:= Etype
(N
);
468 DesigT
: constant Entity_Id
:= Designated_Type
(PtrT
);
470 procedure Apply_Accessibility_Check
472 Built_In_Place
: Boolean := False);
473 -- Ada 2005 (AI-344): For an allocator with a class-wide designated
474 -- type, generate an accessibility check to verify that the level of the
475 -- type of the created object is not deeper than the level of the access
476 -- type. If the type of the qualified expression is class- wide, then
477 -- always generate the check (except in the case where it is known to be
478 -- unnecessary, see comment below). Otherwise, only generate the check
479 -- if the level of the qualified expression type is statically deeper
480 -- than the access type.
482 -- Although the static accessibility will generally have been performed
483 -- as a legality check, it won't have been done in cases where the
484 -- allocator appears in generic body, so a run-time check is needed in
485 -- general. One special case is when the access type is declared in the
486 -- same scope as the class-wide allocator, in which case the check can
487 -- never fail, so it need not be generated.
489 -- As an open issue, there seem to be cases where the static level
490 -- associated with the class-wide object's underlying type is not
491 -- sufficient to perform the proper accessibility check, such as for
492 -- allocators in nested subprograms or accept statements initialized by
493 -- class-wide formals when the actual originates outside at a deeper
494 -- static level. The nested subprogram case might require passing
495 -- accessibility levels along with class-wide parameters, and the task
496 -- case seems to be an actual gap in the language rules that needs to
497 -- be fixed by the ARG. ???
499 -------------------------------
500 -- Apply_Accessibility_Check --
501 -------------------------------
503 procedure Apply_Accessibility_Check
505 Built_In_Place
: Boolean := False)
510 -- Note: we skip the accessibility check for the VM case, since
511 -- there does not seem to be any practical way of implementing it.
513 if Ada_Version
>= Ada_05
514 and then Tagged_Type_Expansion
515 and then Is_Class_Wide_Type
(DesigT
)
516 and then not Scope_Suppress
(Accessibility_Check
)
518 (Type_Access_Level
(Etype
(Exp
)) > Type_Access_Level
(PtrT
)
520 (Is_Class_Wide_Type
(Etype
(Exp
))
521 and then Scope
(PtrT
) /= Current_Scope
))
523 -- If the allocator was built in place Ref is already a reference
524 -- to the access object initialized to the result of the allocator
525 -- (see Exp_Ch6.Make_Build_In_Place_Call_In_Allocator). Otherwise
526 -- it is the entity associated with the object containing the
527 -- address of the allocated object.
529 if Built_In_Place
then
530 Ref_Node
:= New_Copy
(Ref
);
532 Ref_Node
:= New_Reference_To
(Ref
, Loc
);
536 Make_Raise_Program_Error
(Loc
,
540 Build_Get_Access_Level
(Loc
,
541 Make_Attribute_Reference
(Loc
,
543 Attribute_Name
=> Name_Tag
)),
545 Make_Integer_Literal
(Loc
,
546 Type_Access_Level
(PtrT
))),
547 Reason
=> PE_Accessibility_Check_Failed
));
549 end Apply_Accessibility_Check
;
553 Indic
: constant Node_Id
:= Subtype_Mark
(Expression
(N
));
554 T
: constant Entity_Id
:= Entity
(Indic
);
559 TagT
: Entity_Id
:= Empty
;
560 -- Type used as source for tag assignment
562 TagR
: Node_Id
:= Empty
;
563 -- Target reference for tag assignment
565 Aggr_In_Place
: constant Boolean := Is_Delayed_Aggregate
(Exp
);
567 Tag_Assign
: Node_Id
;
570 -- Start of processing for Expand_Allocator_Expression
573 if Is_Tagged_Type
(T
) or else Needs_Finalization
(T
) then
575 -- Ada 2005 (AI-318-02): If the initialization expression is a call
576 -- to a build-in-place function, then access to the allocated object
577 -- must be passed to the function. Currently we limit such functions
578 -- to those with constrained limited result subtypes, but eventually
579 -- we plan to expand the allowed forms of functions that are treated
580 -- as build-in-place.
582 if Ada_Version
>= Ada_05
583 and then Is_Build_In_Place_Function_Call
(Exp
)
585 Make_Build_In_Place_Call_In_Allocator
(N
, Exp
);
586 Apply_Accessibility_Check
(N
, Built_In_Place
=> True);
590 -- Actions inserted before:
591 -- Temp : constant ptr_T := new T'(Expression);
592 -- <no CW> Temp._tag := T'tag;
593 -- <CTRL> Adjust (Finalizable (Temp.all));
594 -- <CTRL> Attach_To_Final_List (Finalizable (Temp.all));
596 -- We analyze by hand the new internal allocator to avoid
597 -- any recursion and inappropriate call to Initialize
599 -- We don't want to remove side effects when the expression must be
600 -- built in place. In the case of a build-in-place function call,
601 -- that could lead to a duplication of the call, which was already
602 -- substituted for the allocator.
604 if not Aggr_In_Place
then
605 Remove_Side_Effects
(Exp
);
609 Make_Defining_Identifier
(Loc
, New_Internal_Name
('P'));
611 -- For a class wide allocation generate the following code:
613 -- type Equiv_Record is record ... end record;
614 -- implicit subtype CW is <Class_Wide_Subytpe>;
615 -- temp : PtrT := new CW'(CW!(expr));
617 if Is_Class_Wide_Type
(T
) then
618 Expand_Subtype_From_Expr
(Empty
, T
, Indic
, Exp
);
620 -- Ada 2005 (AI-251): If the expression is a class-wide interface
621 -- object we generate code to move up "this" to reference the
622 -- base of the object before allocating the new object.
624 -- Note that Exp'Address is recursively expanded into a call
625 -- to Base_Address (Exp.Tag)
627 if Is_Class_Wide_Type
(Etype
(Exp
))
628 and then Is_Interface
(Etype
(Exp
))
629 and then Tagged_Type_Expansion
633 Unchecked_Convert_To
(Entity
(Indic
),
634 Make_Explicit_Dereference
(Loc
,
635 Unchecked_Convert_To
(RTE
(RE_Tag_Ptr
),
636 Make_Attribute_Reference
(Loc
,
638 Attribute_Name
=> Name_Address
)))));
643 Unchecked_Convert_To
(Entity
(Indic
), Exp
));
646 Analyze_And_Resolve
(Expression
(N
), Entity
(Indic
));
649 -- Keep separate the management of allocators returning interfaces
651 if not Is_Interface
(Directly_Designated_Type
(PtrT
)) then
652 if Aggr_In_Place
then
654 Make_Object_Declaration
(Loc
,
655 Defining_Identifier
=> Temp
,
656 Object_Definition
=> New_Reference_To
(PtrT
, Loc
),
659 New_Reference_To
(Etype
(Exp
), Loc
)));
661 -- Copy the Comes_From_Source flag for the allocator we just
662 -- built, since logically this allocator is a replacement of
663 -- the original allocator node. This is for proper handling of
664 -- restriction No_Implicit_Heap_Allocations.
666 Set_Comes_From_Source
667 (Expression
(Tmp_Node
), Comes_From_Source
(N
));
669 Set_No_Initialization
(Expression
(Tmp_Node
));
670 Insert_Action
(N
, Tmp_Node
);
672 if Needs_Finalization
(T
)
673 and then Ekind
(PtrT
) = E_Anonymous_Access_Type
675 -- Create local finalization list for access parameter
677 Flist
:= Get_Allocator_Final_List
(N
, Base_Type
(T
), PtrT
);
680 Convert_Aggr_In_Allocator
(N
, Tmp_Node
, Exp
);
683 Node
:= Relocate_Node
(N
);
686 Make_Object_Declaration
(Loc
,
687 Defining_Identifier
=> Temp
,
688 Constant_Present
=> True,
689 Object_Definition
=> New_Reference_To
(PtrT
, Loc
),
690 Expression
=> Node
));
693 -- Ada 2005 (AI-251): Handle allocators whose designated type is an
694 -- interface type. In this case we use the type of the qualified
695 -- expression to allocate the object.
699 Def_Id
: constant Entity_Id
:=
700 Make_Defining_Identifier
(Loc
,
701 New_Internal_Name
('T'));
706 Make_Full_Type_Declaration
(Loc
,
707 Defining_Identifier
=> Def_Id
,
709 Make_Access_To_Object_Definition
(Loc
,
711 Null_Exclusion_Present
=> False,
712 Constant_Present
=> False,
713 Subtype_Indication
=>
714 New_Reference_To
(Etype
(Exp
), Loc
)));
716 Insert_Action
(N
, New_Decl
);
718 -- Inherit the final chain to ensure that the expansion of the
719 -- aggregate is correct in case of controlled types
721 if Needs_Finalization
(Directly_Designated_Type
(PtrT
)) then
722 Set_Associated_Final_Chain
(Def_Id
,
723 Associated_Final_Chain
(PtrT
));
726 -- Declare the object using the previous type declaration
728 if Aggr_In_Place
then
730 Make_Object_Declaration
(Loc
,
731 Defining_Identifier
=> Temp
,
732 Object_Definition
=> New_Reference_To
(Def_Id
, Loc
),
735 New_Reference_To
(Etype
(Exp
), Loc
)));
737 -- Copy the Comes_From_Source flag for the allocator we just
738 -- built, since logically this allocator is a replacement of
739 -- the original allocator node. This is for proper handling
740 -- of restriction No_Implicit_Heap_Allocations.
742 Set_Comes_From_Source
743 (Expression
(Tmp_Node
), Comes_From_Source
(N
));
745 Set_No_Initialization
(Expression
(Tmp_Node
));
746 Insert_Action
(N
, Tmp_Node
);
748 if Needs_Finalization
(T
)
749 and then Ekind
(PtrT
) = E_Anonymous_Access_Type
751 -- Create local finalization list for access parameter
754 Get_Allocator_Final_List
(N
, Base_Type
(T
), PtrT
);
757 Convert_Aggr_In_Allocator
(N
, Tmp_Node
, Exp
);
759 Node
:= Relocate_Node
(N
);
762 Make_Object_Declaration
(Loc
,
763 Defining_Identifier
=> Temp
,
764 Constant_Present
=> True,
765 Object_Definition
=> New_Reference_To
(Def_Id
, Loc
),
766 Expression
=> Node
));
769 -- Generate an additional object containing the address of the
770 -- returned object. The type of this second object declaration
771 -- is the correct type required for the common processing that
772 -- is still performed by this subprogram. The displacement of
773 -- this pointer to reference the component associated with the
774 -- interface type will be done at the end of common processing.
777 Make_Object_Declaration
(Loc
,
778 Defining_Identifier
=> Make_Defining_Identifier
(Loc
,
779 New_Internal_Name
('P')),
780 Object_Definition
=> New_Reference_To
(PtrT
, Loc
),
781 Expression
=> Unchecked_Convert_To
(PtrT
,
782 New_Reference_To
(Temp
, Loc
)));
784 Insert_Action
(N
, New_Decl
);
786 Tmp_Node
:= New_Decl
;
787 Temp
:= Defining_Identifier
(New_Decl
);
791 Apply_Accessibility_Check
(Temp
);
793 -- Generate the tag assignment
795 -- Suppress the tag assignment when VM_Target because VM tags are
796 -- represented implicitly in objects.
798 if not Tagged_Type_Expansion
then
801 -- Ada 2005 (AI-251): Suppress the tag assignment with class-wide
802 -- interface objects because in this case the tag does not change.
804 elsif Is_Interface
(Directly_Designated_Type
(Etype
(N
))) then
805 pragma Assert
(Is_Class_Wide_Type
806 (Directly_Designated_Type
(Etype
(N
))));
809 elsif Is_Tagged_Type
(T
) and then not Is_Class_Wide_Type
(T
) then
811 TagR
:= New_Reference_To
(Temp
, Loc
);
813 elsif Is_Private_Type
(T
)
814 and then Is_Tagged_Type
(Underlying_Type
(T
))
816 TagT
:= Underlying_Type
(T
);
818 Unchecked_Convert_To
(Underlying_Type
(T
),
819 Make_Explicit_Dereference
(Loc
,
820 Prefix
=> New_Reference_To
(Temp
, Loc
)));
823 if Present
(TagT
) then
825 Make_Assignment_Statement
(Loc
,
827 Make_Selected_Component
(Loc
,
830 New_Reference_To
(First_Tag_Component
(TagT
), Loc
)),
833 Unchecked_Convert_To
(RTE
(RE_Tag
),
835 (Elists
.Node
(First_Elmt
(Access_Disp_Table
(TagT
))),
838 -- The previous assignment has to be done in any case
840 Set_Assignment_OK
(Name
(Tag_Assign
));
841 Insert_Action
(N
, Tag_Assign
);
844 if Needs_Finalization
(DesigT
)
845 and then Needs_Finalization
(T
)
849 Apool
: constant Entity_Id
:=
850 Associated_Storage_Pool
(PtrT
);
853 -- If it is an allocation on the secondary stack (i.e. a value
854 -- returned from a function), the object is attached on the
855 -- caller side as soon as the call is completed (see
856 -- Expand_Ctrl_Function_Call)
858 if Is_RTE
(Apool
, RE_SS_Pool
) then
860 F
: constant Entity_Id
:=
861 Make_Defining_Identifier
(Loc
,
862 New_Internal_Name
('F'));
865 Make_Object_Declaration
(Loc
,
866 Defining_Identifier
=> F
,
867 Object_Definition
=> New_Reference_To
(RTE
868 (RE_Finalizable_Ptr
), Loc
)));
870 Flist
:= New_Reference_To
(F
, Loc
);
871 Attach
:= Make_Integer_Literal
(Loc
, 1);
874 -- Normal case, not a secondary stack allocation
877 if Needs_Finalization
(T
)
878 and then Ekind
(PtrT
) = E_Anonymous_Access_Type
880 -- Create local finalization list for access parameter
883 Get_Allocator_Final_List
(N
, Base_Type
(T
), PtrT
);
885 Flist
:= Find_Final_List
(PtrT
);
888 Attach
:= Make_Integer_Literal
(Loc
, 2);
891 -- Generate an Adjust call if the object will be moved. In Ada
892 -- 2005, the object may be inherently limited, in which case
893 -- there is no Adjust procedure, and the object is built in
894 -- place. In Ada 95, the object can be limited but not
895 -- inherently limited if this allocator came from a return
896 -- statement (we're allocating the result on the secondary
897 -- stack). In that case, the object will be moved, so we _do_
901 and then not Is_Inherently_Limited_Type
(T
)
907 -- An unchecked conversion is needed in the classwide
908 -- case because the designated type can be an ancestor of
909 -- the subtype mark of the allocator.
911 Unchecked_Convert_To
(T
,
912 Make_Explicit_Dereference
(Loc
,
913 Prefix
=> New_Reference_To
(Temp
, Loc
))),
917 With_Attach
=> Attach
,
923 Rewrite
(N
, New_Reference_To
(Temp
, Loc
));
924 Analyze_And_Resolve
(N
, PtrT
);
926 -- Ada 2005 (AI-251): Displace the pointer to reference the record
927 -- component containing the secondary dispatch table of the interface
930 if Is_Interface
(Directly_Designated_Type
(PtrT
)) then
931 Displace_Allocator_Pointer
(N
);
934 elsif Aggr_In_Place
then
936 Make_Defining_Identifier
(Loc
, New_Internal_Name
('P'));
938 Make_Object_Declaration
(Loc
,
939 Defining_Identifier
=> Temp
,
940 Object_Definition
=> New_Reference_To
(PtrT
, Loc
),
941 Expression
=> Make_Allocator
(Loc
,
942 New_Reference_To
(Etype
(Exp
), Loc
)));
944 -- Copy the Comes_From_Source flag for the allocator we just built,
945 -- since logically this allocator is a replacement of the original
946 -- allocator node. This is for proper handling of restriction
947 -- No_Implicit_Heap_Allocations.
949 Set_Comes_From_Source
950 (Expression
(Tmp_Node
), Comes_From_Source
(N
));
952 Set_No_Initialization
(Expression
(Tmp_Node
));
953 Insert_Action
(N
, Tmp_Node
);
954 Convert_Aggr_In_Allocator
(N
, Tmp_Node
, Exp
);
955 Rewrite
(N
, New_Reference_To
(Temp
, Loc
));
956 Analyze_And_Resolve
(N
, PtrT
);
958 elsif Is_Access_Type
(T
)
959 and then Can_Never_Be_Null
(T
)
961 Install_Null_Excluding_Check
(Exp
);
963 elsif Is_Access_Type
(DesigT
)
964 and then Nkind
(Exp
) = N_Allocator
965 and then Nkind
(Expression
(Exp
)) /= N_Qualified_Expression
967 -- Apply constraint to designated subtype indication
969 Apply_Constraint_Check
(Expression
(Exp
),
970 Designated_Type
(DesigT
),
973 if Nkind
(Expression
(Exp
)) = N_Raise_Constraint_Error
then
975 -- Propagate constraint_error to enclosing allocator
977 Rewrite
(Exp
, New_Copy
(Expression
(Exp
)));
981 -- type A is access T1;
982 -- X : A := new T2'(...);
983 -- T1 and T2 can be different subtypes, and we might need to check
984 -- both constraints. First check against the type of the qualified
987 Apply_Constraint_Check
(Exp
, T
, No_Sliding
=> True);
989 -- A check is also needed in cases where the designated subtype is
990 -- constrained and differs from the subtype given in the qualified
991 -- expression. Note that the check on the qualified expression does
992 -- not allow sliding, but this check does (a relaxation from Ada 83).
994 if Is_Constrained
(DesigT
)
995 and then not Subtypes_Statically_Match
(T
, DesigT
)
997 Apply_Constraint_Check
998 (Exp
, DesigT
, No_Sliding
=> False);
1001 -- For an access to unconstrained packed array, GIGI needs to see an
1002 -- expression with a constrained subtype in order to compute the
1003 -- proper size for the allocator.
1005 if Is_Array_Type
(T
)
1006 and then not Is_Constrained
(T
)
1007 and then Is_Packed
(T
)
1010 ConstrT
: constant Entity_Id
:=
1011 Make_Defining_Identifier
(Loc
,
1012 Chars
=> New_Internal_Name
('A'));
1013 Internal_Exp
: constant Node_Id
:= Relocate_Node
(Exp
);
1016 Make_Subtype_Declaration
(Loc
,
1017 Defining_Identifier
=> ConstrT
,
1018 Subtype_Indication
=>
1019 Make_Subtype_From_Expr
(Exp
, T
)));
1020 Freeze_Itype
(ConstrT
, Exp
);
1021 Rewrite
(Exp
, OK_Convert_To
(ConstrT
, Internal_Exp
));
1025 -- Ada 2005 (AI-318-02): If the initialization expression is a call
1026 -- to a build-in-place function, then access to the allocated object
1027 -- must be passed to the function. Currently we limit such functions
1028 -- to those with constrained limited result subtypes, but eventually
1029 -- we plan to expand the allowed forms of functions that are treated
1030 -- as build-in-place.
1032 if Ada_Version
>= Ada_05
1033 and then Is_Build_In_Place_Function_Call
(Exp
)
1035 Make_Build_In_Place_Call_In_Allocator
(N
, Exp
);
1040 when RE_Not_Available
=>
1042 end Expand_Allocator_Expression
;
1044 -----------------------------
1045 -- Expand_Array_Comparison --
1046 -----------------------------
1048 -- Expansion is only required in the case of array types. For the unpacked
1049 -- case, an appropriate runtime routine is called. For packed cases, and
1050 -- also in some other cases where a runtime routine cannot be called, the
1051 -- form of the expansion is:
1053 -- [body for greater_nn; boolean_expression]
1055 -- The body is built by Make_Array_Comparison_Op, and the form of the
1056 -- Boolean expression depends on the operator involved.
1058 procedure Expand_Array_Comparison
(N
: Node_Id
) is
1059 Loc
: constant Source_Ptr
:= Sloc
(N
);
1060 Op1
: Node_Id
:= Left_Opnd
(N
);
1061 Op2
: Node_Id
:= Right_Opnd
(N
);
1062 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
1063 Ctyp
: constant Entity_Id
:= Component_Type
(Typ1
);
1066 Func_Body
: Node_Id
;
1067 Func_Name
: Entity_Id
;
1071 Byte_Addressable
: constant Boolean := System_Storage_Unit
= Byte
'Size;
1072 -- True for byte addressable target
1074 function Length_Less_Than_4
(Opnd
: Node_Id
) return Boolean;
1075 -- Returns True if the length of the given operand is known to be less
1076 -- than 4. Returns False if this length is known to be four or greater
1077 -- or is not known at compile time.
1079 ------------------------
1080 -- Length_Less_Than_4 --
1081 ------------------------
1083 function Length_Less_Than_4
(Opnd
: Node_Id
) return Boolean is
1084 Otyp
: constant Entity_Id
:= Etype
(Opnd
);
1087 if Ekind
(Otyp
) = E_String_Literal_Subtype
then
1088 return String_Literal_Length
(Otyp
) < 4;
1092 Ityp
: constant Entity_Id
:= Etype
(First_Index
(Otyp
));
1093 Lo
: constant Node_Id
:= Type_Low_Bound
(Ityp
);
1094 Hi
: constant Node_Id
:= Type_High_Bound
(Ityp
);
1099 if Compile_Time_Known_Value
(Lo
) then
1100 Lov
:= Expr_Value
(Lo
);
1105 if Compile_Time_Known_Value
(Hi
) then
1106 Hiv
:= Expr_Value
(Hi
);
1111 return Hiv
< Lov
+ 3;
1114 end Length_Less_Than_4
;
1116 -- Start of processing for Expand_Array_Comparison
1119 -- Deal first with unpacked case, where we can call a runtime routine
1120 -- except that we avoid this for targets for which are not addressable
1121 -- by bytes, and for the JVM/CIL, since they do not support direct
1122 -- addressing of array components.
1124 if not Is_Bit_Packed_Array
(Typ1
)
1125 and then Byte_Addressable
1126 and then VM_Target
= No_VM
1128 -- The call we generate is:
1130 -- Compare_Array_xn[_Unaligned]
1131 -- (left'address, right'address, left'length, right'length) <op> 0
1133 -- x = U for unsigned, S for signed
1134 -- n = 8,16,32,64 for component size
1135 -- Add _Unaligned if length < 4 and component size is 8.
1136 -- <op> is the standard comparison operator
1138 if Component_Size
(Typ1
) = 8 then
1139 if Length_Less_Than_4
(Op1
)
1141 Length_Less_Than_4
(Op2
)
1143 if Is_Unsigned_Type
(Ctyp
) then
1144 Comp
:= RE_Compare_Array_U8_Unaligned
;
1146 Comp
:= RE_Compare_Array_S8_Unaligned
;
1150 if Is_Unsigned_Type
(Ctyp
) then
1151 Comp
:= RE_Compare_Array_U8
;
1153 Comp
:= RE_Compare_Array_S8
;
1157 elsif Component_Size
(Typ1
) = 16 then
1158 if Is_Unsigned_Type
(Ctyp
) then
1159 Comp
:= RE_Compare_Array_U16
;
1161 Comp
:= RE_Compare_Array_S16
;
1164 elsif Component_Size
(Typ1
) = 32 then
1165 if Is_Unsigned_Type
(Ctyp
) then
1166 Comp
:= RE_Compare_Array_U32
;
1168 Comp
:= RE_Compare_Array_S32
;
1171 else pragma Assert
(Component_Size
(Typ1
) = 64);
1172 if Is_Unsigned_Type
(Ctyp
) then
1173 Comp
:= RE_Compare_Array_U64
;
1175 Comp
:= RE_Compare_Array_S64
;
1179 Remove_Side_Effects
(Op1
, Name_Req
=> True);
1180 Remove_Side_Effects
(Op2
, Name_Req
=> True);
1183 Make_Function_Call
(Sloc
(Op1
),
1184 Name
=> New_Occurrence_Of
(RTE
(Comp
), Loc
),
1186 Parameter_Associations
=> New_List
(
1187 Make_Attribute_Reference
(Loc
,
1188 Prefix
=> Relocate_Node
(Op1
),
1189 Attribute_Name
=> Name_Address
),
1191 Make_Attribute_Reference
(Loc
,
1192 Prefix
=> Relocate_Node
(Op2
),
1193 Attribute_Name
=> Name_Address
),
1195 Make_Attribute_Reference
(Loc
,
1196 Prefix
=> Relocate_Node
(Op1
),
1197 Attribute_Name
=> Name_Length
),
1199 Make_Attribute_Reference
(Loc
,
1200 Prefix
=> Relocate_Node
(Op2
),
1201 Attribute_Name
=> Name_Length
))));
1204 Make_Integer_Literal
(Sloc
(Op2
),
1207 Analyze_And_Resolve
(Op1
, Standard_Integer
);
1208 Analyze_And_Resolve
(Op2
, Standard_Integer
);
1212 -- Cases where we cannot make runtime call
1214 -- For (a <= b) we convert to not (a > b)
1216 if Chars
(N
) = Name_Op_Le
then
1222 Right_Opnd
=> Op2
)));
1223 Analyze_And_Resolve
(N
, Standard_Boolean
);
1226 -- For < the Boolean expression is
1227 -- greater__nn (op2, op1)
1229 elsif Chars
(N
) = Name_Op_Lt
then
1230 Func_Body
:= Make_Array_Comparison_Op
(Typ1
, N
);
1234 Op1
:= Right_Opnd
(N
);
1235 Op2
:= Left_Opnd
(N
);
1237 -- For (a >= b) we convert to not (a < b)
1239 elsif Chars
(N
) = Name_Op_Ge
then
1245 Right_Opnd
=> Op2
)));
1246 Analyze_And_Resolve
(N
, Standard_Boolean
);
1249 -- For > the Boolean expression is
1250 -- greater__nn (op1, op2)
1253 pragma Assert
(Chars
(N
) = Name_Op_Gt
);
1254 Func_Body
:= Make_Array_Comparison_Op
(Typ1
, N
);
1257 Func_Name
:= Defining_Unit_Name
(Specification
(Func_Body
));
1259 Make_Function_Call
(Loc
,
1260 Name
=> New_Reference_To
(Func_Name
, Loc
),
1261 Parameter_Associations
=> New_List
(Op1
, Op2
));
1263 Insert_Action
(N
, Func_Body
);
1265 Analyze_And_Resolve
(N
, Standard_Boolean
);
1268 when RE_Not_Available
=>
1270 end Expand_Array_Comparison
;
1272 ---------------------------
1273 -- Expand_Array_Equality --
1274 ---------------------------
1276 -- Expand an equality function for multi-dimensional arrays. Here is an
1277 -- example of such a function for Nb_Dimension = 2
1279 -- function Enn (A : atyp; B : btyp) return boolean is
1281 -- if (A'length (1) = 0 or else A'length (2) = 0)
1283 -- (B'length (1) = 0 or else B'length (2) = 0)
1285 -- return True; -- RM 4.5.2(22)
1288 -- if A'length (1) /= B'length (1)
1290 -- A'length (2) /= B'length (2)
1292 -- return False; -- RM 4.5.2(23)
1296 -- A1 : Index_T1 := A'first (1);
1297 -- B1 : Index_T1 := B'first (1);
1301 -- A2 : Index_T2 := A'first (2);
1302 -- B2 : Index_T2 := B'first (2);
1305 -- if A (A1, A2) /= B (B1, B2) then
1309 -- exit when A2 = A'last (2);
1310 -- A2 := Index_T2'succ (A2);
1311 -- B2 := Index_T2'succ (B2);
1315 -- exit when A1 = A'last (1);
1316 -- A1 := Index_T1'succ (A1);
1317 -- B1 := Index_T1'succ (B1);
1324 -- Note on the formal types used (atyp and btyp). If either of the arrays
1325 -- is of a private type, we use the underlying type, and do an unchecked
1326 -- conversion of the actual. If either of the arrays has a bound depending
1327 -- on a discriminant, then we use the base type since otherwise we have an
1328 -- escaped discriminant in the function.
1330 -- If both arrays are constrained and have the same bounds, we can generate
1331 -- a loop with an explicit iteration scheme using a 'Range attribute over
1334 function Expand_Array_Equality
1339 Typ
: Entity_Id
) return Node_Id
1341 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
1342 Decls
: constant List_Id
:= New_List
;
1343 Index_List1
: constant List_Id
:= New_List
;
1344 Index_List2
: constant List_Id
:= New_List
;
1348 Func_Name
: Entity_Id
;
1349 Func_Body
: Node_Id
;
1351 A
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uA
);
1352 B
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uB
);
1356 -- The parameter types to be used for the formals
1361 Num
: Int
) return Node_Id
;
1362 -- This builds the attribute reference Arr'Nam (Expr)
1364 function Component_Equality
(Typ
: Entity_Id
) return Node_Id
;
1365 -- Create one statement to compare corresponding components, designated
1366 -- by a full set of indices.
1368 function Get_Arg_Type
(N
: Node_Id
) return Entity_Id
;
1369 -- Given one of the arguments, computes the appropriate type to be used
1370 -- for that argument in the corresponding function formal
1372 function Handle_One_Dimension
1374 Index
: Node_Id
) return Node_Id
;
1375 -- This procedure returns the following code
1378 -- Bn : Index_T := B'First (N);
1382 -- exit when An = A'Last (N);
1383 -- An := Index_T'Succ (An)
1384 -- Bn := Index_T'Succ (Bn)
1388 -- If both indices are constrained and identical, the procedure
1389 -- returns a simpler loop:
1391 -- for An in A'Range (N) loop
1395 -- N is the dimension for which we are generating a loop. Index is the
1396 -- N'th index node, whose Etype is Index_Type_n in the above code. The
1397 -- xxx statement is either the loop or declare for the next dimension
1398 -- or if this is the last dimension the comparison of corresponding
1399 -- components of the arrays.
1401 -- The actual way the code works is to return the comparison of
1402 -- corresponding components for the N+1 call. That's neater!
1404 function Test_Empty_Arrays
return Node_Id
;
1405 -- This function constructs the test for both arrays being empty
1406 -- (A'length (1) = 0 or else A'length (2) = 0 or else ...)
1408 -- (B'length (1) = 0 or else B'length (2) = 0 or else ...)
1410 function Test_Lengths_Correspond
return Node_Id
;
1411 -- This function constructs the test for arrays having different lengths
1412 -- in at least one index position, in which case the resulting code is:
1414 -- A'length (1) /= B'length (1)
1416 -- A'length (2) /= B'length (2)
1427 Num
: Int
) return Node_Id
1431 Make_Attribute_Reference
(Loc
,
1432 Attribute_Name
=> Nam
,
1433 Prefix
=> New_Reference_To
(Arr
, Loc
),
1434 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, Num
)));
1437 ------------------------
1438 -- Component_Equality --
1439 ------------------------
1441 function Component_Equality
(Typ
: Entity_Id
) return Node_Id
is
1446 -- if a(i1...) /= b(j1...) then return false; end if;
1449 Make_Indexed_Component
(Loc
,
1450 Prefix
=> Make_Identifier
(Loc
, Chars
(A
)),
1451 Expressions
=> Index_List1
);
1454 Make_Indexed_Component
(Loc
,
1455 Prefix
=> Make_Identifier
(Loc
, Chars
(B
)),
1456 Expressions
=> Index_List2
);
1458 Test
:= Expand_Composite_Equality
1459 (Nod
, Component_Type
(Typ
), L
, R
, Decls
);
1461 -- If some (sub)component is an unchecked_union, the whole operation
1462 -- will raise program error.
1464 if Nkind
(Test
) = N_Raise_Program_Error
then
1466 -- This node is going to be inserted at a location where a
1467 -- statement is expected: clear its Etype so analysis will set
1468 -- it to the expected Standard_Void_Type.
1470 Set_Etype
(Test
, Empty
);
1475 Make_Implicit_If_Statement
(Nod
,
1476 Condition
=> Make_Op_Not
(Loc
, Right_Opnd
=> Test
),
1477 Then_Statements
=> New_List
(
1478 Make_Simple_Return_Statement
(Loc
,
1479 Expression
=> New_Occurrence_Of
(Standard_False
, Loc
))));
1481 end Component_Equality
;
1487 function Get_Arg_Type
(N
: Node_Id
) return Entity_Id
is
1498 T
:= Underlying_Type
(T
);
1500 X
:= First_Index
(T
);
1501 while Present
(X
) loop
1502 if Denotes_Discriminant
(Type_Low_Bound
(Etype
(X
)))
1504 Denotes_Discriminant
(Type_High_Bound
(Etype
(X
)))
1517 --------------------------
1518 -- Handle_One_Dimension --
1519 ---------------------------
1521 function Handle_One_Dimension
1523 Index
: Node_Id
) return Node_Id
1525 Need_Separate_Indexes
: constant Boolean :=
1527 or else not Is_Constrained
(Ltyp
);
1528 -- If the index types are identical, and we are working with
1529 -- constrained types, then we can use the same index for both
1532 An
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
,
1533 Chars
=> New_Internal_Name
('A'));
1536 Index_T
: Entity_Id
;
1541 if N
> Number_Dimensions
(Ltyp
) then
1542 return Component_Equality
(Ltyp
);
1545 -- Case where we generate a loop
1547 Index_T
:= Base_Type
(Etype
(Index
));
1549 if Need_Separate_Indexes
then
1551 Make_Defining_Identifier
(Loc
,
1552 Chars
=> New_Internal_Name
('B'));
1557 Append
(New_Reference_To
(An
, Loc
), Index_List1
);
1558 Append
(New_Reference_To
(Bn
, Loc
), Index_List2
);
1560 Stm_List
:= New_List
(
1561 Handle_One_Dimension
(N
+ 1, Next_Index
(Index
)));
1563 if Need_Separate_Indexes
then
1565 -- Generate guard for loop, followed by increments of indices
1567 Append_To
(Stm_List
,
1568 Make_Exit_Statement
(Loc
,
1571 Left_Opnd
=> New_Reference_To
(An
, Loc
),
1572 Right_Opnd
=> Arr_Attr
(A
, Name_Last
, N
))));
1574 Append_To
(Stm_List
,
1575 Make_Assignment_Statement
(Loc
,
1576 Name
=> New_Reference_To
(An
, Loc
),
1578 Make_Attribute_Reference
(Loc
,
1579 Prefix
=> New_Reference_To
(Index_T
, Loc
),
1580 Attribute_Name
=> Name_Succ
,
1581 Expressions
=> New_List
(New_Reference_To
(An
, Loc
)))));
1583 Append_To
(Stm_List
,
1584 Make_Assignment_Statement
(Loc
,
1585 Name
=> New_Reference_To
(Bn
, Loc
),
1587 Make_Attribute_Reference
(Loc
,
1588 Prefix
=> New_Reference_To
(Index_T
, Loc
),
1589 Attribute_Name
=> Name_Succ
,
1590 Expressions
=> New_List
(New_Reference_To
(Bn
, Loc
)))));
1593 -- If separate indexes, we need a declare block for An and Bn, and a
1594 -- loop without an iteration scheme.
1596 if Need_Separate_Indexes
then
1598 Make_Implicit_Loop_Statement
(Nod
, Statements
=> Stm_List
);
1601 Make_Block_Statement
(Loc
,
1602 Declarations
=> New_List
(
1603 Make_Object_Declaration
(Loc
,
1604 Defining_Identifier
=> An
,
1605 Object_Definition
=> New_Reference_To
(Index_T
, Loc
),
1606 Expression
=> Arr_Attr
(A
, Name_First
, N
)),
1608 Make_Object_Declaration
(Loc
,
1609 Defining_Identifier
=> Bn
,
1610 Object_Definition
=> New_Reference_To
(Index_T
, Loc
),
1611 Expression
=> Arr_Attr
(B
, Name_First
, N
))),
1613 Handled_Statement_Sequence
=>
1614 Make_Handled_Sequence_Of_Statements
(Loc
,
1615 Statements
=> New_List
(Loop_Stm
)));
1617 -- If no separate indexes, return loop statement with explicit
1618 -- iteration scheme on its own
1622 Make_Implicit_Loop_Statement
(Nod
,
1623 Statements
=> Stm_List
,
1625 Make_Iteration_Scheme
(Loc
,
1626 Loop_Parameter_Specification
=>
1627 Make_Loop_Parameter_Specification
(Loc
,
1628 Defining_Identifier
=> An
,
1629 Discrete_Subtype_Definition
=>
1630 Arr_Attr
(A
, Name_Range
, N
))));
1633 end Handle_One_Dimension
;
1635 -----------------------
1636 -- Test_Empty_Arrays --
1637 -----------------------
1639 function Test_Empty_Arrays
return Node_Id
is
1649 for J
in 1 .. Number_Dimensions
(Ltyp
) loop
1652 Left_Opnd
=> Arr_Attr
(A
, Name_Length
, J
),
1653 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0));
1657 Left_Opnd
=> Arr_Attr
(B
, Name_Length
, J
),
1658 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0));
1667 Left_Opnd
=> Relocate_Node
(Alist
),
1668 Right_Opnd
=> Atest
);
1672 Left_Opnd
=> Relocate_Node
(Blist
),
1673 Right_Opnd
=> Btest
);
1680 Right_Opnd
=> Blist
);
1681 end Test_Empty_Arrays
;
1683 -----------------------------
1684 -- Test_Lengths_Correspond --
1685 -----------------------------
1687 function Test_Lengths_Correspond
return Node_Id
is
1693 for J
in 1 .. Number_Dimensions
(Ltyp
) loop
1696 Left_Opnd
=> Arr_Attr
(A
, Name_Length
, J
),
1697 Right_Opnd
=> Arr_Attr
(B
, Name_Length
, J
));
1704 Left_Opnd
=> Relocate_Node
(Result
),
1705 Right_Opnd
=> Rtest
);
1710 end Test_Lengths_Correspond
;
1712 -- Start of processing for Expand_Array_Equality
1715 Ltyp
:= Get_Arg_Type
(Lhs
);
1716 Rtyp
:= Get_Arg_Type
(Rhs
);
1718 -- For now, if the argument types are not the same, go to the base type,
1719 -- since the code assumes that the formals have the same type. This is
1720 -- fixable in future ???
1722 if Ltyp
/= Rtyp
then
1723 Ltyp
:= Base_Type
(Ltyp
);
1724 Rtyp
:= Base_Type
(Rtyp
);
1725 pragma Assert
(Ltyp
= Rtyp
);
1728 -- Build list of formals for function
1730 Formals
:= New_List
(
1731 Make_Parameter_Specification
(Loc
,
1732 Defining_Identifier
=> A
,
1733 Parameter_Type
=> New_Reference_To
(Ltyp
, Loc
)),
1735 Make_Parameter_Specification
(Loc
,
1736 Defining_Identifier
=> B
,
1737 Parameter_Type
=> New_Reference_To
(Rtyp
, Loc
)));
1739 Func_Name
:= Make_Defining_Identifier
(Loc
, New_Internal_Name
('E'));
1741 -- Build statement sequence for function
1744 Make_Subprogram_Body
(Loc
,
1746 Make_Function_Specification
(Loc
,
1747 Defining_Unit_Name
=> Func_Name
,
1748 Parameter_Specifications
=> Formals
,
1749 Result_Definition
=> New_Reference_To
(Standard_Boolean
, Loc
)),
1751 Declarations
=> Decls
,
1753 Handled_Statement_Sequence
=>
1754 Make_Handled_Sequence_Of_Statements
(Loc
,
1755 Statements
=> New_List
(
1757 Make_Implicit_If_Statement
(Nod
,
1758 Condition
=> Test_Empty_Arrays
,
1759 Then_Statements
=> New_List
(
1760 Make_Simple_Return_Statement
(Loc
,
1762 New_Occurrence_Of
(Standard_True
, Loc
)))),
1764 Make_Implicit_If_Statement
(Nod
,
1765 Condition
=> Test_Lengths_Correspond
,
1766 Then_Statements
=> New_List
(
1767 Make_Simple_Return_Statement
(Loc
,
1769 New_Occurrence_Of
(Standard_False
, Loc
)))),
1771 Handle_One_Dimension
(1, First_Index
(Ltyp
)),
1773 Make_Simple_Return_Statement
(Loc
,
1774 Expression
=> New_Occurrence_Of
(Standard_True
, Loc
)))));
1776 Set_Has_Completion
(Func_Name
, True);
1777 Set_Is_Inlined
(Func_Name
);
1779 -- If the array type is distinct from the type of the arguments, it
1780 -- is the full view of a private type. Apply an unchecked conversion
1781 -- to insure that analysis of the call succeeds.
1791 or else Base_Type
(Etype
(Lhs
)) /= Base_Type
(Ltyp
)
1793 L
:= OK_Convert_To
(Ltyp
, Lhs
);
1797 or else Base_Type
(Etype
(Rhs
)) /= Base_Type
(Rtyp
)
1799 R
:= OK_Convert_To
(Rtyp
, Rhs
);
1802 Actuals
:= New_List
(L
, R
);
1805 Append_To
(Bodies
, Func_Body
);
1808 Make_Function_Call
(Loc
,
1809 Name
=> New_Reference_To
(Func_Name
, Loc
),
1810 Parameter_Associations
=> Actuals
);
1811 end Expand_Array_Equality
;
1813 -----------------------------
1814 -- Expand_Boolean_Operator --
1815 -----------------------------
1817 -- Note that we first get the actual subtypes of the operands, since we
1818 -- always want to deal with types that have bounds.
1820 procedure Expand_Boolean_Operator
(N
: Node_Id
) is
1821 Typ
: constant Entity_Id
:= Etype
(N
);
1824 -- Special case of bit packed array where both operands are known to be
1825 -- properly aligned. In this case we use an efficient run time routine
1826 -- to carry out the operation (see System.Bit_Ops).
1828 if Is_Bit_Packed_Array
(Typ
)
1829 and then not Is_Possibly_Unaligned_Object
(Left_Opnd
(N
))
1830 and then not Is_Possibly_Unaligned_Object
(Right_Opnd
(N
))
1832 Expand_Packed_Boolean_Operator
(N
);
1836 -- For the normal non-packed case, the general expansion is to build
1837 -- function for carrying out the comparison (use Make_Boolean_Array_Op)
1838 -- and then inserting it into the tree. The original operator node is
1839 -- then rewritten as a call to this function. We also use this in the
1840 -- packed case if either operand is a possibly unaligned object.
1843 Loc
: constant Source_Ptr
:= Sloc
(N
);
1844 L
: constant Node_Id
:= Relocate_Node
(Left_Opnd
(N
));
1845 R
: constant Node_Id
:= Relocate_Node
(Right_Opnd
(N
));
1846 Func_Body
: Node_Id
;
1847 Func_Name
: Entity_Id
;
1850 Convert_To_Actual_Subtype
(L
);
1851 Convert_To_Actual_Subtype
(R
);
1852 Ensure_Defined
(Etype
(L
), N
);
1853 Ensure_Defined
(Etype
(R
), N
);
1854 Apply_Length_Check
(R
, Etype
(L
));
1856 if Nkind
(N
) = N_Op_Xor
then
1857 Silly_Boolean_Array_Xor_Test
(N
, Etype
(L
));
1860 if Nkind
(Parent
(N
)) = N_Assignment_Statement
1861 and then Safe_In_Place_Array_Op
(Name
(Parent
(N
)), L
, R
)
1863 Build_Boolean_Array_Proc_Call
(Parent
(N
), L
, R
);
1865 elsif Nkind
(Parent
(N
)) = N_Op_Not
1866 and then Nkind
(N
) = N_Op_And
1868 Safe_In_Place_Array_Op
(Name
(Parent
(Parent
(N
))), L
, R
)
1873 Func_Body
:= Make_Boolean_Array_Op
(Etype
(L
), N
);
1874 Func_Name
:= Defining_Unit_Name
(Specification
(Func_Body
));
1875 Insert_Action
(N
, Func_Body
);
1877 -- Now rewrite the expression with a call
1880 Make_Function_Call
(Loc
,
1881 Name
=> New_Reference_To
(Func_Name
, Loc
),
1882 Parameter_Associations
=>
1885 Make_Type_Conversion
1886 (Loc
, New_Reference_To
(Etype
(L
), Loc
), R
))));
1888 Analyze_And_Resolve
(N
, Typ
);
1891 end Expand_Boolean_Operator
;
1893 -------------------------------
1894 -- Expand_Composite_Equality --
1895 -------------------------------
1897 -- This function is only called for comparing internal fields of composite
1898 -- types when these fields are themselves composites. This is a special
1899 -- case because it is not possible to respect normal Ada visibility rules.
1901 function Expand_Composite_Equality
1906 Bodies
: List_Id
) return Node_Id
1908 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
1909 Full_Type
: Entity_Id
;
1914 if Is_Private_Type
(Typ
) then
1915 Full_Type
:= Underlying_Type
(Typ
);
1920 -- Defense against malformed private types with no completion the error
1921 -- will be diagnosed later by check_completion
1923 if No
(Full_Type
) then
1924 return New_Reference_To
(Standard_False
, Loc
);
1927 Full_Type
:= Base_Type
(Full_Type
);
1929 if Is_Array_Type
(Full_Type
) then
1931 -- If the operand is an elementary type other than a floating-point
1932 -- type, then we can simply use the built-in block bitwise equality,
1933 -- since the predefined equality operators always apply and bitwise
1934 -- equality is fine for all these cases.
1936 if Is_Elementary_Type
(Component_Type
(Full_Type
))
1937 and then not Is_Floating_Point_Type
(Component_Type
(Full_Type
))
1939 return Make_Op_Eq
(Loc
, Left_Opnd
=> Lhs
, Right_Opnd
=> Rhs
);
1941 -- For composite component types, and floating-point types, use the
1942 -- expansion. This deals with tagged component types (where we use
1943 -- the applicable equality routine) and floating-point, (where we
1944 -- need to worry about negative zeroes), and also the case of any
1945 -- composite type recursively containing such fields.
1948 return Expand_Array_Equality
(Nod
, Lhs
, Rhs
, Bodies
, Full_Type
);
1951 elsif Is_Tagged_Type
(Full_Type
) then
1953 -- Call the primitive operation "=" of this type
1955 if Is_Class_Wide_Type
(Full_Type
) then
1956 Full_Type
:= Root_Type
(Full_Type
);
1959 -- If this is derived from an untagged private type completed with a
1960 -- tagged type, it does not have a full view, so we use the primitive
1961 -- operations of the private type. This check should no longer be
1962 -- necessary when these types receive their full views ???
1964 if Is_Private_Type
(Typ
)
1965 and then not Is_Tagged_Type
(Typ
)
1966 and then not Is_Controlled
(Typ
)
1967 and then Is_Derived_Type
(Typ
)
1968 and then No
(Full_View
(Typ
))
1970 Prim
:= First_Elmt
(Collect_Primitive_Operations
(Typ
));
1972 Prim
:= First_Elmt
(Primitive_Operations
(Full_Type
));
1976 Eq_Op
:= Node
(Prim
);
1977 exit when Chars
(Eq_Op
) = Name_Op_Eq
1978 and then Etype
(First_Formal
(Eq_Op
)) =
1979 Etype
(Next_Formal
(First_Formal
(Eq_Op
)))
1980 and then Base_Type
(Etype
(Eq_Op
)) = Standard_Boolean
;
1982 pragma Assert
(Present
(Prim
));
1985 Eq_Op
:= Node
(Prim
);
1988 Make_Function_Call
(Loc
,
1989 Name
=> New_Reference_To
(Eq_Op
, Loc
),
1990 Parameter_Associations
=>
1992 (Unchecked_Convert_To
(Etype
(First_Formal
(Eq_Op
)), Lhs
),
1993 Unchecked_Convert_To
(Etype
(First_Formal
(Eq_Op
)), Rhs
)));
1995 elsif Is_Record_Type
(Full_Type
) then
1996 Eq_Op
:= TSS
(Full_Type
, TSS_Composite_Equality
);
1998 if Present
(Eq_Op
) then
1999 if Etype
(First_Formal
(Eq_Op
)) /= Full_Type
then
2001 -- Inherited equality from parent type. Convert the actuals to
2002 -- match signature of operation.
2005 T
: constant Entity_Id
:= Etype
(First_Formal
(Eq_Op
));
2009 Make_Function_Call
(Loc
,
2010 Name
=> New_Reference_To
(Eq_Op
, Loc
),
2011 Parameter_Associations
=>
2012 New_List
(OK_Convert_To
(T
, Lhs
),
2013 OK_Convert_To
(T
, Rhs
)));
2017 -- Comparison between Unchecked_Union components
2019 if Is_Unchecked_Union
(Full_Type
) then
2021 Lhs_Type
: Node_Id
:= Full_Type
;
2022 Rhs_Type
: Node_Id
:= Full_Type
;
2023 Lhs_Discr_Val
: Node_Id
;
2024 Rhs_Discr_Val
: Node_Id
;
2029 if Nkind
(Lhs
) = N_Selected_Component
then
2030 Lhs_Type
:= Etype
(Entity
(Selector_Name
(Lhs
)));
2035 if Nkind
(Rhs
) = N_Selected_Component
then
2036 Rhs_Type
:= Etype
(Entity
(Selector_Name
(Rhs
)));
2039 -- Lhs of the composite equality
2041 if Is_Constrained
(Lhs_Type
) then
2043 -- Since the enclosing record type can never be an
2044 -- Unchecked_Union (this code is executed for records
2045 -- that do not have variants), we may reference its
2048 if Nkind
(Lhs
) = N_Selected_Component
2049 and then Has_Per_Object_Constraint
(
2050 Entity
(Selector_Name
(Lhs
)))
2053 Make_Selected_Component
(Loc
,
2054 Prefix
=> Prefix
(Lhs
),
2057 Get_Discriminant_Value
(
2058 First_Discriminant
(Lhs_Type
),
2060 Stored_Constraint
(Lhs_Type
))));
2063 Lhs_Discr_Val
:= New_Copy
(
2064 Get_Discriminant_Value
(
2065 First_Discriminant
(Lhs_Type
),
2067 Stored_Constraint
(Lhs_Type
)));
2071 -- It is not possible to infer the discriminant since
2072 -- the subtype is not constrained.
2075 Make_Raise_Program_Error
(Loc
,
2076 Reason
=> PE_Unchecked_Union_Restriction
);
2079 -- Rhs of the composite equality
2081 if Is_Constrained
(Rhs_Type
) then
2082 if Nkind
(Rhs
) = N_Selected_Component
2083 and then Has_Per_Object_Constraint
(
2084 Entity
(Selector_Name
(Rhs
)))
2087 Make_Selected_Component
(Loc
,
2088 Prefix
=> Prefix
(Rhs
),
2091 Get_Discriminant_Value
(
2092 First_Discriminant
(Rhs_Type
),
2094 Stored_Constraint
(Rhs_Type
))));
2097 Rhs_Discr_Val
:= New_Copy
(
2098 Get_Discriminant_Value
(
2099 First_Discriminant
(Rhs_Type
),
2101 Stored_Constraint
(Rhs_Type
)));
2106 Make_Raise_Program_Error
(Loc
,
2107 Reason
=> PE_Unchecked_Union_Restriction
);
2110 -- Call the TSS equality function with the inferred
2111 -- discriminant values.
2114 Make_Function_Call
(Loc
,
2115 Name
=> New_Reference_To
(Eq_Op
, Loc
),
2116 Parameter_Associations
=> New_List
(
2124 -- Shouldn't this be an else, we can't fall through the above
2128 Make_Function_Call
(Loc
,
2129 Name
=> New_Reference_To
(Eq_Op
, Loc
),
2130 Parameter_Associations
=> New_List
(Lhs
, Rhs
));
2134 return Expand_Record_Equality
(Nod
, Full_Type
, Lhs
, Rhs
, Bodies
);
2138 -- It can be a simple record or the full view of a scalar private
2140 return Make_Op_Eq
(Loc
, Left_Opnd
=> Lhs
, Right_Opnd
=> Rhs
);
2142 end Expand_Composite_Equality
;
2144 ------------------------
2145 -- Expand_Concatenate --
2146 ------------------------
2148 procedure Expand_Concatenate
(Cnode
: Node_Id
; Opnds
: List_Id
) is
2149 Loc
: constant Source_Ptr
:= Sloc
(Cnode
);
2151 Atyp
: constant Entity_Id
:= Base_Type
(Etype
(Cnode
));
2152 -- Result type of concatenation
2154 Ctyp
: constant Entity_Id
:= Base_Type
(Component_Type
(Etype
(Cnode
)));
2155 -- Component type. Elements of this component type can appear as one
2156 -- of the operands of concatenation as well as arrays.
2158 Istyp
: constant Entity_Id
:= Etype
(First_Index
(Atyp
));
2161 Ityp
: constant Entity_Id
:= Base_Type
(Istyp
);
2162 -- Index type. This is the base type of the index subtype, and is used
2163 -- for all computed bounds (which may be out of range of Istyp in the
2164 -- case of null ranges).
2167 -- This is the type we use to do arithmetic to compute the bounds and
2168 -- lengths of operands. The choice of this type is a little subtle and
2169 -- is discussed in a separate section at the start of the body code.
2171 Concatenation_Error
: exception;
2172 -- Raised if concatenation is sure to raise a CE
2174 Result_May_Be_Null
: Boolean := True;
2175 -- Reset to False if at least one operand is encountered which is known
2176 -- at compile time to be non-null. Used for handling the special case
2177 -- of setting the high bound to the last operand high bound for a null
2178 -- result, thus ensuring a proper high bound in the super-flat case.
2180 N
: constant Nat
:= List_Length
(Opnds
);
2181 -- Number of concatenation operands including possibly null operands
2184 -- Number of operands excluding any known to be null, except that the
2185 -- last operand is always retained, in case it provides the bounds for
2189 -- Current operand being processed in the loop through operands. After
2190 -- this loop is complete, always contains the last operand (which is not
2191 -- the same as Operands (NN), since null operands are skipped).
2193 -- Arrays describing the operands, only the first NN entries of each
2194 -- array are set (NN < N when we exclude known null operands).
2196 Is_Fixed_Length
: array (1 .. N
) of Boolean;
2197 -- True if length of corresponding operand known at compile time
2199 Operands
: array (1 .. N
) of Node_Id
;
2200 -- Set to the corresponding entry in the Opnds list (but note that null
2201 -- operands are excluded, so not all entries in the list are stored).
2203 Fixed_Length
: array (1 .. N
) of Uint
;
2204 -- Set to length of operand. Entries in this array are set only if the
2205 -- corresponding entry in Is_Fixed_Length is True.
2207 Opnd_Low_Bound
: array (1 .. N
) of Node_Id
;
2208 -- Set to lower bound of operand. Either an integer literal in the case
2209 -- where the bound is known at compile time, else actual lower bound.
2210 -- The operand low bound is of type Ityp.
2212 Var_Length
: array (1 .. N
) of Entity_Id
;
2213 -- Set to an entity of type Natural that contains the length of an
2214 -- operand whose length is not known at compile time. Entries in this
2215 -- array are set only if the corresponding entry in Is_Fixed_Length
2216 -- is False. The entity is of type Artyp.
2218 Aggr_Length
: array (0 .. N
) of Node_Id
;
2219 -- The J'th entry in an expression node that represents the total length
2220 -- of operands 1 through J. It is either an integer literal node, or a
2221 -- reference to a constant entity with the right value, so it is fine
2222 -- to just do a Copy_Node to get an appropriate copy. The extra zero'th
2223 -- entry always is set to zero. The length is of type Artyp.
2225 Low_Bound
: Node_Id
;
2226 -- A tree node representing the low bound of the result (of type Ityp).
2227 -- This is either an integer literal node, or an identifier reference to
2228 -- a constant entity initialized to the appropriate value.
2230 Last_Opnd_High_Bound
: Node_Id
;
2231 -- A tree node representing the high bound of the last operand. This
2232 -- need only be set if the result could be null. It is used for the
2233 -- special case of setting the right high bound for a null result.
2234 -- This is of type Ityp.
2236 High_Bound
: Node_Id
;
2237 -- A tree node representing the high bound of the result (of type Ityp)
2240 -- Result of the concatenation (of type Ityp)
2242 Actions
: constant List_Id
:= New_List
;
2243 -- Collect actions to be inserted if Save_Space is False
2245 Save_Space
: Boolean;
2246 pragma Warnings
(Off
, Save_Space
);
2247 -- Set to True if we are saving generated code space by calling routines
2248 -- in packages System.Concat_n.
2250 Known_Non_Null_Operand_Seen
: Boolean;
2251 -- Set True during generation of the assignements of operands into
2252 -- result once an operand known to be non-null has been seen.
2254 function Make_Artyp_Literal
(Val
: Nat
) return Node_Id
;
2255 -- This function makes an N_Integer_Literal node that is returned in
2256 -- analyzed form with the type set to Artyp. Importantly this literal
2257 -- is not flagged as static, so that if we do computations with it that
2258 -- result in statically detected out of range conditions, we will not
2259 -- generate error messages but instead warning messages.
2261 function To_Artyp
(X
: Node_Id
) return Node_Id
;
2262 -- Given a node of type Ityp, returns the corresponding value of type
2263 -- Artyp. For non-enumeration types, this is a plain integer conversion.
2264 -- For enum types, the Pos of the value is returned.
2266 function To_Ityp
(X
: Node_Id
) return Node_Id
;
2267 -- The inverse function (uses Val in the case of enumeration types)
2269 ------------------------
2270 -- Make_Artyp_Literal --
2271 ------------------------
2273 function Make_Artyp_Literal
(Val
: Nat
) return Node_Id
is
2274 Result
: constant Node_Id
:= Make_Integer_Literal
(Loc
, Val
);
2276 Set_Etype
(Result
, Artyp
);
2277 Set_Analyzed
(Result
, True);
2278 Set_Is_Static_Expression
(Result
, False);
2280 end Make_Artyp_Literal
;
2286 function To_Artyp
(X
: Node_Id
) return Node_Id
is
2288 if Ityp
= Base_Type
(Artyp
) then
2291 elsif Is_Enumeration_Type
(Ityp
) then
2293 Make_Attribute_Reference
(Loc
,
2294 Prefix
=> New_Occurrence_Of
(Ityp
, Loc
),
2295 Attribute_Name
=> Name_Pos
,
2296 Expressions
=> New_List
(X
));
2299 return Convert_To
(Artyp
, X
);
2307 function To_Ityp
(X
: Node_Id
) return Node_Id
is
2309 if Is_Enumeration_Type
(Ityp
) then
2311 Make_Attribute_Reference
(Loc
,
2312 Prefix
=> New_Occurrence_Of
(Ityp
, Loc
),
2313 Attribute_Name
=> Name_Val
,
2314 Expressions
=> New_List
(X
));
2316 -- Case where we will do a type conversion
2319 if Ityp
= Base_Type
(Artyp
) then
2322 return Convert_To
(Ityp
, X
);
2327 -- Local Declarations
2329 Opnd_Typ
: Entity_Id
;
2337 -- Choose an appropriate computational type
2339 -- We will be doing calculations of lengths and bounds in this routine
2340 -- and computing one from the other in some cases, e.g. getting the high
2341 -- bound by adding the length-1 to the low bound.
2343 -- We can't just use the index type, or even its base type for this
2344 -- purpose for two reasons. First it might be an enumeration type which
2345 -- is not suitable fo computations of any kind, and second it may simply
2346 -- not have enough range. For example if the index type is -128..+127
2347 -- then lengths can be up to 256, which is out of range of the type.
2349 -- For enumeration types, we can simply use Standard_Integer, this is
2350 -- sufficient since the actual number of enumeration literals cannot
2351 -- possibly exceed the range of integer (remember we will be doing the
2352 -- arithmetic with POS values, not representation values).
2354 if Is_Enumeration_Type
(Ityp
) then
2355 Artyp
:= Standard_Integer
;
2357 -- If index type is Positive, we use the standard unsigned type, to give
2358 -- more room on the top of the range, obviating the need for an overflow
2359 -- check when creating the upper bound. This is needed to avoid junk
2360 -- overflow checks in the common case of String types.
2362 -- ??? Disabled for now
2364 -- elsif Istyp = Standard_Positive then
2365 -- Artyp := Standard_Unsigned;
2367 -- For modular types, we use a 32-bit modular type for types whose size
2368 -- is in the range 1-31 bits. For 32-bit unsigned types, we use the
2369 -- identity type, and for larger unsigned types we use 64-bits.
2371 elsif Is_Modular_Integer_Type
(Ityp
) then
2372 if RM_Size
(Ityp
) < RM_Size
(Standard_Unsigned
) then
2373 Artyp
:= Standard_Unsigned
;
2374 elsif RM_Size
(Ityp
) = RM_Size
(Standard_Unsigned
) then
2377 Artyp
:= RTE
(RE_Long_Long_Unsigned
);
2380 -- Similar treatment for signed types
2383 if RM_Size
(Ityp
) < RM_Size
(Standard_Integer
) then
2384 Artyp
:= Standard_Integer
;
2385 elsif RM_Size
(Ityp
) = RM_Size
(Standard_Integer
) then
2388 Artyp
:= Standard_Long_Long_Integer
;
2392 -- Supply dummy entry at start of length array
2394 Aggr_Length
(0) := Make_Artyp_Literal
(0);
2396 -- Go through operands setting up the above arrays
2400 Opnd
:= Remove_Head
(Opnds
);
2401 Opnd_Typ
:= Etype
(Opnd
);
2403 -- The parent got messed up when we put the operands in a list,
2404 -- so now put back the proper parent for the saved operand.
2406 Set_Parent
(Opnd
, Parent
(Cnode
));
2408 -- Set will be True when we have setup one entry in the array
2412 -- Singleton element (or character literal) case
2414 if Base_Type
(Opnd_Typ
) = Ctyp
then
2416 Operands
(NN
) := Opnd
;
2417 Is_Fixed_Length
(NN
) := True;
2418 Fixed_Length
(NN
) := Uint_1
;
2419 Result_May_Be_Null
:= False;
2421 -- Set low bound of operand (no need to set Last_Opnd_High_Bound
2422 -- since we know that the result cannot be null).
2424 Opnd_Low_Bound
(NN
) :=
2425 Make_Attribute_Reference
(Loc
,
2426 Prefix
=> New_Reference_To
(Istyp
, Loc
),
2427 Attribute_Name
=> Name_First
);
2431 -- String literal case (can only occur for strings of course)
2433 elsif Nkind
(Opnd
) = N_String_Literal
then
2434 Len
:= String_Literal_Length
(Opnd_Typ
);
2437 Result_May_Be_Null
:= False;
2440 -- Capture last operand high bound if result could be null
2442 if J
= N
and then Result_May_Be_Null
then
2443 Last_Opnd_High_Bound
:=
2446 New_Copy_Tree
(String_Literal_Low_Bound
(Opnd_Typ
)),
2447 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1));
2450 -- Skip null string literal
2452 if J
< N
and then Len
= 0 then
2457 Operands
(NN
) := Opnd
;
2458 Is_Fixed_Length
(NN
) := True;
2460 -- Set length and bounds
2462 Fixed_Length
(NN
) := Len
;
2464 Opnd_Low_Bound
(NN
) :=
2465 New_Copy_Tree
(String_Literal_Low_Bound
(Opnd_Typ
));
2472 -- Check constrained case with known bounds
2474 if Is_Constrained
(Opnd_Typ
) then
2476 Index
: constant Node_Id
:= First_Index
(Opnd_Typ
);
2477 Indx_Typ
: constant Entity_Id
:= Etype
(Index
);
2478 Lo
: constant Node_Id
:= Type_Low_Bound
(Indx_Typ
);
2479 Hi
: constant Node_Id
:= Type_High_Bound
(Indx_Typ
);
2482 -- Fixed length constrained array type with known at compile
2483 -- time bounds is last case of fixed length operand.
2485 if Compile_Time_Known_Value
(Lo
)
2487 Compile_Time_Known_Value
(Hi
)
2490 Loval
: constant Uint
:= Expr_Value
(Lo
);
2491 Hival
: constant Uint
:= Expr_Value
(Hi
);
2492 Len
: constant Uint
:=
2493 UI_Max
(Hival
- Loval
+ 1, Uint_0
);
2497 Result_May_Be_Null
:= False;
2500 -- Capture last operand bound if result could be null
2502 if J
= N
and then Result_May_Be_Null
then
2503 Last_Opnd_High_Bound
:=
2505 Make_Integer_Literal
(Loc
,
2506 Intval
=> Expr_Value
(Hi
)));
2509 -- Exclude null length case unless last operand
2511 if J
< N
and then Len
= 0 then
2516 Operands
(NN
) := Opnd
;
2517 Is_Fixed_Length
(NN
) := True;
2518 Fixed_Length
(NN
) := Len
;
2520 Opnd_Low_Bound
(NN
) := To_Ityp
(
2521 Make_Integer_Literal
(Loc
,
2522 Intval
=> Expr_Value
(Lo
)));
2530 -- All cases where the length is not known at compile time, or the
2531 -- special case of an operand which is known to be null but has a
2532 -- lower bound other than 1 or is other than a string type.
2537 -- Capture operand bounds
2539 Opnd_Low_Bound
(NN
) :=
2540 Make_Attribute_Reference
(Loc
,
2542 Duplicate_Subexpr
(Opnd
, Name_Req
=> True),
2543 Attribute_Name
=> Name_First
);
2545 if J
= N
and Result_May_Be_Null
then
2546 Last_Opnd_High_Bound
:=
2548 Make_Attribute_Reference
(Loc
,
2550 Duplicate_Subexpr
(Opnd
, Name_Req
=> True),
2551 Attribute_Name
=> Name_Last
));
2554 -- Capture length of operand in entity
2556 Operands
(NN
) := Opnd
;
2557 Is_Fixed_Length
(NN
) := False;
2560 Make_Defining_Identifier
(Loc
,
2561 Chars
=> New_Internal_Name
('L'));
2564 Make_Object_Declaration
(Loc
,
2565 Defining_Identifier
=> Var_Length
(NN
),
2566 Constant_Present
=> True,
2568 Object_Definition
=>
2569 New_Occurrence_Of
(Artyp
, Loc
),
2572 Make_Attribute_Reference
(Loc
,
2574 Duplicate_Subexpr
(Opnd
, Name_Req
=> True),
2575 Attribute_Name
=> Name_Length
)));
2579 -- Set next entry in aggregate length array
2581 -- For first entry, make either integer literal for fixed length
2582 -- or a reference to the saved length for variable length.
2585 if Is_Fixed_Length
(1) then
2587 Make_Integer_Literal
(Loc
,
2588 Intval
=> Fixed_Length
(1));
2591 New_Reference_To
(Var_Length
(1), Loc
);
2594 -- If entry is fixed length and only fixed lengths so far, make
2595 -- appropriate new integer literal adding new length.
2597 elsif Is_Fixed_Length
(NN
)
2598 and then Nkind
(Aggr_Length
(NN
- 1)) = N_Integer_Literal
2601 Make_Integer_Literal
(Loc
,
2602 Intval
=> Fixed_Length
(NN
) + Intval
(Aggr_Length
(NN
- 1)));
2604 -- All other cases, construct an addition node for the length and
2605 -- create an entity initialized to this length.
2609 Make_Defining_Identifier
(Loc
,
2610 Chars
=> New_Internal_Name
('L'));
2612 if Is_Fixed_Length
(NN
) then
2613 Clen
:= Make_Integer_Literal
(Loc
, Fixed_Length
(NN
));
2615 Clen
:= New_Reference_To
(Var_Length
(NN
), Loc
);
2619 Make_Object_Declaration
(Loc
,
2620 Defining_Identifier
=> Ent
,
2621 Constant_Present
=> True,
2623 Object_Definition
=>
2624 New_Occurrence_Of
(Artyp
, Loc
),
2628 Left_Opnd
=> New_Copy
(Aggr_Length
(NN
- 1)),
2629 Right_Opnd
=> Clen
)));
2631 Aggr_Length
(NN
) := Make_Identifier
(Loc
, Chars
=> Chars
(Ent
));
2638 -- If we have only skipped null operands, return the last operand
2645 -- If we have only one non-null operand, return it and we are done.
2646 -- There is one case in which this cannot be done, and that is when
2647 -- the sole operand is of the element type, in which case it must be
2648 -- converted to an array, and the easiest way of doing that is to go
2649 -- through the normal general circuit.
2652 and then Base_Type
(Etype
(Operands
(1))) /= Ctyp
2654 Result
:= Operands
(1);
2658 -- Cases where we have a real concatenation
2660 -- Next step is to find the low bound for the result array that we
2661 -- will allocate. The rules for this are in (RM 4.5.6(5-7)).
2663 -- If the ultimate ancestor of the index subtype is a constrained array
2664 -- definition, then the lower bound is that of the index subtype as
2665 -- specified by (RM 4.5.3(6)).
2667 -- The right test here is to go to the root type, and then the ultimate
2668 -- ancestor is the first subtype of this root type.
2670 if Is_Constrained
(First_Subtype
(Root_Type
(Atyp
))) then
2672 Make_Attribute_Reference
(Loc
,
2674 New_Occurrence_Of
(First_Subtype
(Root_Type
(Atyp
)), Loc
),
2675 Attribute_Name
=> Name_First
);
2677 -- If the first operand in the list has known length we know that
2678 -- the lower bound of the result is the lower bound of this operand.
2680 elsif Is_Fixed_Length
(1) then
2681 Low_Bound
:= Opnd_Low_Bound
(1);
2683 -- OK, we don't know the lower bound, we have to build a horrible
2684 -- expression actions node of the form
2686 -- if Cond1'Length /= 0 then
2689 -- if Opnd2'Length /= 0 then
2694 -- The nesting ends either when we hit an operand whose length is known
2695 -- at compile time, or on reaching the last operand, whose low bound we
2696 -- take unconditionally whether or not it is null. It's easiest to do
2697 -- this with a recursive procedure:
2701 function Get_Known_Bound
(J
: Nat
) return Node_Id
;
2702 -- Returns the lower bound determined by operands J .. NN
2704 ---------------------
2705 -- Get_Known_Bound --
2706 ---------------------
2708 function Get_Known_Bound
(J
: Nat
) return Node_Id
is
2710 if Is_Fixed_Length
(J
) or else J
= NN
then
2711 return New_Copy
(Opnd_Low_Bound
(J
));
2715 Make_Conditional_Expression
(Loc
,
2716 Expressions
=> New_List
(
2719 Left_Opnd
=> New_Reference_To
(Var_Length
(J
), Loc
),
2720 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0)),
2722 New_Copy
(Opnd_Low_Bound
(J
)),
2723 Get_Known_Bound
(J
+ 1)));
2725 end Get_Known_Bound
;
2729 Make_Defining_Identifier
(Loc
, Chars
=> New_Internal_Name
('L'));
2732 Make_Object_Declaration
(Loc
,
2733 Defining_Identifier
=> Ent
,
2734 Constant_Present
=> True,
2735 Object_Definition
=> New_Occurrence_Of
(Ityp
, Loc
),
2736 Expression
=> Get_Known_Bound
(1)));
2738 Low_Bound
:= New_Reference_To
(Ent
, Loc
);
2742 -- Now we can safely compute the upper bound, normally
2743 -- Low_Bound + Length - 1.
2748 Left_Opnd
=> To_Artyp
(New_Copy
(Low_Bound
)),
2750 Make_Op_Subtract
(Loc
,
2751 Left_Opnd
=> New_Copy
(Aggr_Length
(NN
)),
2752 Right_Opnd
=> Make_Artyp_Literal
(1))));
2754 -- Note that calculation of the high bound may cause overflow in some
2755 -- very weird cases, so in the general case we need an overflow check on
2756 -- the high bound. We can avoid this for the common case of string types
2757 -- and other types whose index is Positive, since we chose a wider range
2758 -- for the arithmetic type.
2760 if Istyp
/= Standard_Positive
then
2761 Activate_Overflow_Check
(High_Bound
);
2764 -- Handle the exceptional case where the result is null, in which case
2765 -- case the bounds come from the last operand (so that we get the proper
2766 -- bounds if the last operand is super-flat).
2768 if Result_May_Be_Null
then
2770 Make_Conditional_Expression
(Loc
,
2771 Expressions
=> New_List
(
2773 Left_Opnd
=> New_Copy
(Aggr_Length
(NN
)),
2774 Right_Opnd
=> Make_Artyp_Literal
(0)),
2775 Last_Opnd_High_Bound
,
2779 -- Here is where we insert the saved up actions
2781 Insert_Actions
(Cnode
, Actions
, Suppress
=> All_Checks
);
2783 -- Now we construct an array object with appropriate bounds
2786 Make_Defining_Identifier
(Loc
,
2787 Chars
=> New_Internal_Name
('S'));
2789 -- If the bound is statically known to be out of range, we do not want
2790 -- to abort, we want a warning and a runtime constraint error. Note that
2791 -- we have arranged that the result will not be treated as a static
2792 -- constant, so we won't get an illegality during this insertion.
2794 Insert_Action
(Cnode
,
2795 Make_Object_Declaration
(Loc
,
2796 Defining_Identifier
=> Ent
,
2797 Object_Definition
=>
2798 Make_Subtype_Indication
(Loc
,
2799 Subtype_Mark
=> New_Occurrence_Of
(Atyp
, Loc
),
2801 Make_Index_Or_Discriminant_Constraint
(Loc
,
2802 Constraints
=> New_List
(
2804 Low_Bound
=> Low_Bound
,
2805 High_Bound
=> High_Bound
))))),
2806 Suppress
=> All_Checks
);
2808 -- If the result of the concatenation appears as the initializing
2809 -- expression of an object declaration, we can just rename the
2810 -- result, rather than copying it.
2812 Set_OK_To_Rename
(Ent
);
2814 -- Catch the static out of range case now
2816 if Raises_Constraint_Error
(High_Bound
) then
2817 raise Concatenation_Error
;
2820 -- Now we will generate the assignments to do the actual concatenation
2822 -- There is one case in which we will not do this, namely when all the
2823 -- following conditions are met:
2825 -- The result type is Standard.String
2827 -- There are nine or fewer retained (non-null) operands
2829 -- The optimization level is -O0
2831 -- The corresponding System.Concat_n.Str_Concat_n routine is
2832 -- available in the run time.
2834 -- The debug flag gnatd.c is not set
2836 -- If all these conditions are met then we generate a call to the
2837 -- relevant concatenation routine. The purpose of this is to avoid
2838 -- undesirable code bloat at -O0.
2840 if Atyp
= Standard_String
2841 and then NN
in 2 .. 9
2842 and then (Opt
.Optimization_Level
= 0 or else Debug_Flag_Dot_CC
)
2843 and then not Debug_Flag_Dot_C
2846 RR
: constant array (Nat
range 2 .. 9) of RE_Id
:=
2857 if RTE_Available
(RR
(NN
)) then
2859 Opnds
: constant List_Id
:=
2860 New_List
(New_Occurrence_Of
(Ent
, Loc
));
2863 for J
in 1 .. NN
loop
2864 if Is_List_Member
(Operands
(J
)) then
2865 Remove
(Operands
(J
));
2868 if Base_Type
(Etype
(Operands
(J
))) = Ctyp
then
2870 Make_Aggregate
(Loc
,
2871 Component_Associations
=> New_List
(
2872 Make_Component_Association
(Loc
,
2873 Choices
=> New_List
(
2874 Make_Integer_Literal
(Loc
, 1)),
2875 Expression
=> Operands
(J
)))));
2878 Append_To
(Opnds
, Operands
(J
));
2882 Insert_Action
(Cnode
,
2883 Make_Procedure_Call_Statement
(Loc
,
2884 Name
=> New_Reference_To
(RTE
(RR
(NN
)), Loc
),
2885 Parameter_Associations
=> Opnds
));
2887 Result
:= New_Reference_To
(Ent
, Loc
);
2894 -- Not special case so generate the assignments
2896 Known_Non_Null_Operand_Seen
:= False;
2898 for J
in 1 .. NN
loop
2900 Lo
: constant Node_Id
:=
2902 Left_Opnd
=> To_Artyp
(New_Copy
(Low_Bound
)),
2903 Right_Opnd
=> Aggr_Length
(J
- 1));
2905 Hi
: constant Node_Id
:=
2907 Left_Opnd
=> To_Artyp
(New_Copy
(Low_Bound
)),
2909 Make_Op_Subtract
(Loc
,
2910 Left_Opnd
=> Aggr_Length
(J
),
2911 Right_Opnd
=> Make_Artyp_Literal
(1)));
2914 -- Singleton case, simple assignment
2916 if Base_Type
(Etype
(Operands
(J
))) = Ctyp
then
2917 Known_Non_Null_Operand_Seen
:= True;
2918 Insert_Action
(Cnode
,
2919 Make_Assignment_Statement
(Loc
,
2921 Make_Indexed_Component
(Loc
,
2922 Prefix
=> New_Occurrence_Of
(Ent
, Loc
),
2923 Expressions
=> New_List
(To_Ityp
(Lo
))),
2924 Expression
=> Operands
(J
)),
2925 Suppress
=> All_Checks
);
2927 -- Array case, slice assignment, skipped when argument is fixed
2928 -- length and known to be null.
2930 elsif (not Is_Fixed_Length
(J
)) or else (Fixed_Length
(J
) > 0) then
2933 Make_Assignment_Statement
(Loc
,
2937 New_Occurrence_Of
(Ent
, Loc
),
2940 Low_Bound
=> To_Ityp
(Lo
),
2941 High_Bound
=> To_Ityp
(Hi
))),
2942 Expression
=> Operands
(J
));
2944 if Is_Fixed_Length
(J
) then
2945 Known_Non_Null_Operand_Seen
:= True;
2947 elsif not Known_Non_Null_Operand_Seen
then
2949 -- Here if operand length is not statically known and no
2950 -- operand known to be non-null has been processed yet.
2951 -- If operand length is 0, we do not need to perform the
2952 -- assignment, and we must avoid the evaluation of the
2953 -- high bound of the slice, since it may underflow if the
2954 -- low bound is Ityp'First.
2957 Make_Implicit_If_Statement
(Cnode
,
2961 New_Occurrence_Of
(Var_Length
(J
), Loc
),
2962 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0)),
2967 Insert_Action
(Cnode
, Assign
, Suppress
=> All_Checks
);
2973 -- Finally we build the result, which is a reference to the array object
2975 Result
:= New_Reference_To
(Ent
, Loc
);
2978 Rewrite
(Cnode
, Result
);
2979 Analyze_And_Resolve
(Cnode
, Atyp
);
2982 when Concatenation_Error
=>
2984 -- Kill warning generated for the declaration of the static out of
2985 -- range high bound, and instead generate a Constraint_Error with
2986 -- an appropriate specific message.
2988 Kill_Dead_Code
(Declaration_Node
(Entity
(High_Bound
)));
2989 Apply_Compile_Time_Constraint_Error
2991 Msg
=> "concatenation result upper bound out of range?",
2992 Reason
=> CE_Range_Check_Failed
);
2993 -- Set_Etype (Cnode, Atyp);
2994 end Expand_Concatenate
;
2996 ------------------------
2997 -- Expand_N_Allocator --
2998 ------------------------
3000 procedure Expand_N_Allocator
(N
: Node_Id
) is
3001 PtrT
: constant Entity_Id
:= Etype
(N
);
3002 Dtyp
: constant Entity_Id
:= Designated_Type
(PtrT
);
3003 Etyp
: constant Entity_Id
:= Etype
(Expression
(N
));
3004 Loc
: constant Source_Ptr
:= Sloc
(N
);
3009 procedure Complete_Coextension_Finalization
;
3010 -- Generate finalization calls for all nested coextensions of N. This
3011 -- routine may allocate list controllers if necessary.
3013 procedure Rewrite_Coextension
(N
: Node_Id
);
3014 -- Static coextensions have the same lifetime as the entity they
3015 -- constrain. Such occurrences can be rewritten as aliased objects
3016 -- and their unrestricted access used instead of the coextension.
3018 function Size_In_Storage_Elements
(E
: Entity_Id
) return Node_Id
;
3019 -- Given a constrained array type E, returns a node representing the
3020 -- code to compute the size in storage elements for the given type.
3021 -- This is done without using the attribute (which malfunctions for
3024 ---------------------------------------
3025 -- Complete_Coextension_Finalization --
3026 ---------------------------------------
3028 procedure Complete_Coextension_Finalization
is
3030 Coext_Elmt
: Elmt_Id
;
3034 function Inside_A_Return_Statement
(N
: Node_Id
) return Boolean;
3035 -- Determine whether node N is part of a return statement
3037 function Needs_Initialization_Call
(N
: Node_Id
) return Boolean;
3038 -- Determine whether node N is a subtype indicator allocator which
3039 -- acts a coextension. Such coextensions need initialization.
3041 -------------------------------
3042 -- Inside_A_Return_Statement --
3043 -------------------------------
3045 function Inside_A_Return_Statement
(N
: Node_Id
) return Boolean is
3050 while Present
(P
) loop
3052 (P
, N_Extended_Return_Statement
, N_Simple_Return_Statement
)
3056 -- Stop the traversal when we reach a subprogram body
3058 elsif Nkind
(P
) = N_Subprogram_Body
then
3066 end Inside_A_Return_Statement
;
3068 -------------------------------
3069 -- Needs_Initialization_Call --
3070 -------------------------------
3072 function Needs_Initialization_Call
(N
: Node_Id
) return Boolean is
3076 if Nkind
(N
) = N_Explicit_Dereference
3077 and then Nkind
(Prefix
(N
)) = N_Identifier
3078 and then Nkind
(Parent
(Entity
(Prefix
(N
)))) =
3079 N_Object_Declaration
3081 Obj_Decl
:= Parent
(Entity
(Prefix
(N
)));
3084 Present
(Expression
(Obj_Decl
))
3085 and then Nkind
(Expression
(Obj_Decl
)) = N_Allocator
3086 and then Nkind
(Expression
(Expression
(Obj_Decl
))) /=
3087 N_Qualified_Expression
;
3091 end Needs_Initialization_Call
;
3093 -- Start of processing for Complete_Coextension_Finalization
3096 -- When a coextension root is inside a return statement, we need to
3097 -- use the finalization chain of the function's scope. This does not
3098 -- apply for controlled named access types because in those cases we
3099 -- can use the finalization chain of the type itself.
3101 if Inside_A_Return_Statement
(N
)
3103 (Ekind
(PtrT
) = E_Anonymous_Access_Type
3105 (Ekind
(PtrT
) = E_Access_Type
3106 and then No
(Associated_Final_Chain
(PtrT
))))
3110 Outer_S
: Entity_Id
;
3111 S
: Entity_Id
:= Current_Scope
;
3114 while Present
(S
) and then S
/= Standard_Standard
loop
3115 if Ekind
(S
) = E_Function
then
3116 Outer_S
:= Scope
(S
);
3118 -- Retrieve the declaration of the body
3123 (Corresponding_Body
(Parent
(Parent
(S
)))));
3130 -- Push the scope of the function body since we are inserting
3131 -- the list before the body, but we are currently in the body
3132 -- itself. Override the finalization list of PtrT since the
3133 -- finalization context is now different.
3135 Push_Scope
(Outer_S
);
3136 Build_Final_List
(Decl
, PtrT
);
3140 -- The root allocator may not be controlled, but it still needs a
3141 -- finalization list for all nested coextensions.
3143 elsif No
(Associated_Final_Chain
(PtrT
)) then
3144 Build_Final_List
(N
, PtrT
);
3148 Make_Selected_Component
(Loc
,
3150 New_Reference_To
(Associated_Final_Chain
(PtrT
), Loc
),
3152 Make_Identifier
(Loc
, Name_F
));
3154 Coext_Elmt
:= First_Elmt
(Coextensions
(N
));
3155 while Present
(Coext_Elmt
) loop
3156 Coext
:= Node
(Coext_Elmt
);
3161 if Nkind
(Coext
) = N_Identifier
then
3163 Make_Unchecked_Type_Conversion
(Loc
,
3164 Subtype_Mark
=> New_Reference_To
(Etype
(Coext
), Loc
),
3166 Make_Explicit_Dereference
(Loc
,
3167 Prefix
=> New_Copy_Tree
(Coext
)));
3169 Ref
:= New_Copy_Tree
(Coext
);
3172 -- No initialization call if not allowed
3174 Check_Restriction
(No_Default_Initialization
, N
);
3176 if not Restriction_Active
(No_Default_Initialization
) then
3180 -- attach_to_final_list (Ref, Flist, 2)
3182 if Needs_Initialization_Call
(Coext
) then
3186 Typ
=> Etype
(Coext
),
3188 With_Attach
=> Make_Integer_Literal
(Loc
, Uint_2
)));
3191 -- attach_to_final_list (Ref, Flist, 2)
3197 Flist_Ref
=> New_Copy_Tree
(Flist
),
3198 With_Attach
=> Make_Integer_Literal
(Loc
, Uint_2
)));
3202 Next_Elmt
(Coext_Elmt
);
3204 end Complete_Coextension_Finalization
;
3206 -------------------------
3207 -- Rewrite_Coextension --
3208 -------------------------
3210 procedure Rewrite_Coextension
(N
: Node_Id
) is
3211 Temp
: constant Node_Id
:=
3212 Make_Defining_Identifier
(Loc
,
3213 New_Internal_Name
('C'));
3216 -- Cnn : aliased Etyp;
3218 Decl
: constant Node_Id
:=
3219 Make_Object_Declaration
(Loc
,
3220 Defining_Identifier
=> Temp
,
3221 Aliased_Present
=> True,
3222 Object_Definition
=>
3223 New_Occurrence_Of
(Etyp
, Loc
));
3227 if Nkind
(Expression
(N
)) = N_Qualified_Expression
then
3228 Set_Expression
(Decl
, Expression
(Expression
(N
)));
3231 -- Find the proper insertion node for the declaration
3234 while Present
(Nod
) loop
3235 exit when Nkind
(Nod
) in N_Statement_Other_Than_Procedure_Call
3236 or else Nkind
(Nod
) = N_Procedure_Call_Statement
3237 or else Nkind
(Nod
) in N_Declaration
;
3238 Nod
:= Parent
(Nod
);
3241 Insert_Before
(Nod
, Decl
);
3245 Make_Attribute_Reference
(Loc
,
3246 Prefix
=> New_Occurrence_Of
(Temp
, Loc
),
3247 Attribute_Name
=> Name_Unrestricted_Access
));
3249 Analyze_And_Resolve
(N
, PtrT
);
3250 end Rewrite_Coextension
;
3252 ------------------------------
3253 -- Size_In_Storage_Elements --
3254 ------------------------------
3256 function Size_In_Storage_Elements
(E
: Entity_Id
) return Node_Id
is
3258 -- Logically this just returns E'Max_Size_In_Storage_Elements.
3259 -- However, the reason for the existence of this function is
3260 -- to construct a test for sizes too large, which means near the
3261 -- 32-bit limit on a 32-bit machine, and precisely the trouble
3262 -- is that we get overflows when sizes are greater than 2**31.
3264 -- So what we end up doing for array types is to use the expression:
3266 -- number-of-elements * component_type'Max_Size_In_Storage_Elements
3268 -- which avoids this problem. All this is a big bogus, but it does
3269 -- mean we catch common cases of trying to allocate arrays that
3270 -- are too large, and which in the absence of a check results in
3271 -- undetected chaos ???
3278 for J
in 1 .. Number_Dimensions
(E
) loop
3280 Make_Attribute_Reference
(Loc
,
3281 Prefix
=> New_Occurrence_Of
(E
, Loc
),
3282 Attribute_Name
=> Name_Length
,
3283 Expressions
=> New_List
(
3284 Make_Integer_Literal
(Loc
, J
)));
3291 Make_Op_Multiply
(Loc
,
3298 Make_Op_Multiply
(Loc
,
3301 Make_Attribute_Reference
(Loc
,
3302 Prefix
=> New_Occurrence_Of
(Component_Type
(E
), Loc
),
3303 Attribute_Name
=> Name_Max_Size_In_Storage_Elements
));
3305 end Size_In_Storage_Elements
;
3307 -- Start of processing for Expand_N_Allocator
3310 -- RM E.2.3(22). We enforce that the expected type of an allocator
3311 -- shall not be a remote access-to-class-wide-limited-private type
3313 -- Why is this being done at expansion time, seems clearly wrong ???
3315 Validate_Remote_Access_To_Class_Wide_Type
(N
);
3317 -- Set the Storage Pool
3319 Set_Storage_Pool
(N
, Associated_Storage_Pool
(Root_Type
(PtrT
)));
3321 if Present
(Storage_Pool
(N
)) then
3322 if Is_RTE
(Storage_Pool
(N
), RE_SS_Pool
) then
3323 if VM_Target
= No_VM
then
3324 Set_Procedure_To_Call
(N
, RTE
(RE_SS_Allocate
));
3327 elsif Is_Class_Wide_Type
(Etype
(Storage_Pool
(N
))) then
3328 Set_Procedure_To_Call
(N
, RTE
(RE_Allocate_Any
));
3331 Set_Procedure_To_Call
(N
,
3332 Find_Prim_Op
(Etype
(Storage_Pool
(N
)), Name_Allocate
));
3336 -- Under certain circumstances we can replace an allocator by an access
3337 -- to statically allocated storage. The conditions, as noted in AARM
3338 -- 3.10 (10c) are as follows:
3340 -- Size and initial value is known at compile time
3341 -- Access type is access-to-constant
3343 -- The allocator is not part of a constraint on a record component,
3344 -- because in that case the inserted actions are delayed until the
3345 -- record declaration is fully analyzed, which is too late for the
3346 -- analysis of the rewritten allocator.
3348 if Is_Access_Constant
(PtrT
)
3349 and then Nkind
(Expression
(N
)) = N_Qualified_Expression
3350 and then Compile_Time_Known_Value
(Expression
(Expression
(N
)))
3351 and then Size_Known_At_Compile_Time
(Etype
(Expression
3353 and then not Is_Record_Type
(Current_Scope
)
3355 -- Here we can do the optimization. For the allocator
3359 -- We insert an object declaration
3361 -- Tnn : aliased x := y;
3363 -- and replace the allocator by Tnn'Unrestricted_Access. Tnn is
3364 -- marked as requiring static allocation.
3367 Make_Defining_Identifier
(Loc
, New_Internal_Name
('T'));
3369 Desig
:= Subtype_Mark
(Expression
(N
));
3371 -- If context is constrained, use constrained subtype directly,
3372 -- so that the constant is not labelled as having a nominally
3373 -- unconstrained subtype.
3375 if Entity
(Desig
) = Base_Type
(Dtyp
) then
3376 Desig
:= New_Occurrence_Of
(Dtyp
, Loc
);
3380 Make_Object_Declaration
(Loc
,
3381 Defining_Identifier
=> Temp
,
3382 Aliased_Present
=> True,
3383 Constant_Present
=> Is_Access_Constant
(PtrT
),
3384 Object_Definition
=> Desig
,
3385 Expression
=> Expression
(Expression
(N
))));
3388 Make_Attribute_Reference
(Loc
,
3389 Prefix
=> New_Occurrence_Of
(Temp
, Loc
),
3390 Attribute_Name
=> Name_Unrestricted_Access
));
3392 Analyze_And_Resolve
(N
, PtrT
);
3394 -- We set the variable as statically allocated, since we don't want
3395 -- it going on the stack of the current procedure!
3397 Set_Is_Statically_Allocated
(Temp
);
3401 -- Same if the allocator is an access discriminant for a local object:
3402 -- instead of an allocator we create a local value and constrain the
3403 -- the enclosing object with the corresponding access attribute.
3405 if Is_Static_Coextension
(N
) then
3406 Rewrite_Coextension
(N
);
3410 -- The current allocator creates an object which may contain nested
3411 -- coextensions. Use the current allocator's finalization list to
3412 -- generate finalization call for all nested coextensions.
3414 if Is_Coextension_Root
(N
) then
3415 Complete_Coextension_Finalization
;
3418 -- Check for size too large, we do this because the back end misses
3419 -- proper checks here and can generate rubbish allocation calls when
3420 -- we are near the limit. We only do this for the 32-bit address case
3421 -- since that is from a practical point of view where we see a problem.
3423 if System_Address_Size
= 32
3424 and then not Storage_Checks_Suppressed
(PtrT
)
3425 and then not Storage_Checks_Suppressed
(Dtyp
)
3426 and then not Storage_Checks_Suppressed
(Etyp
)
3428 -- The check we want to generate should look like
3430 -- if Etyp'Max_Size_In_Storage_Elements > 3.5 gigabytes then
3431 -- raise Storage_Error;
3434 -- where 3.5 gigabytes is a constant large enough to accomodate any
3435 -- reasonable request for. But we can't do it this way because at
3436 -- least at the moment we don't compute this attribute right, and
3437 -- can silently give wrong results when the result gets large. Since
3438 -- this is all about large results, that's bad, so instead we only
3439 -- apply the check for constrained arrays, and manually compute the
3440 -- value of the attribute ???
3442 if Is_Array_Type
(Etyp
) and then Is_Constrained
(Etyp
) then
3444 Make_Raise_Storage_Error
(Loc
,
3447 Left_Opnd
=> Size_In_Storage_Elements
(Etyp
),
3449 Make_Integer_Literal
(Loc
,
3450 Intval
=> Uint_7
* (Uint_2
** 29))),
3451 Reason
=> SE_Object_Too_Large
));
3455 -- Handle case of qualified expression (other than optimization above)
3456 -- First apply constraint checks, because the bounds or discriminants
3457 -- in the aggregate might not match the subtype mark in the allocator.
3459 if Nkind
(Expression
(N
)) = N_Qualified_Expression
then
3460 Apply_Constraint_Check
3461 (Expression
(Expression
(N
)), Etype
(Expression
(N
)));
3463 Expand_Allocator_Expression
(N
);
3467 -- If the allocator is for a type which requires initialization, and
3468 -- there is no initial value (i.e. operand is a subtype indication
3469 -- rather than a qualified expression), then we must generate a call to
3470 -- the initialization routine using an expressions action node:
3472 -- [Pnnn : constant ptr_T := new (T); Init (Pnnn.all,...); Pnnn]
3474 -- Here ptr_T is the pointer type for the allocator, and T is the
3475 -- subtype of the allocator. A special case arises if the designated
3476 -- type of the access type is a task or contains tasks. In this case
3477 -- the call to Init (Temp.all ...) is replaced by code that ensures
3478 -- that tasks get activated (see Exp_Ch9.Build_Task_Allocate_Block
3479 -- for details). In addition, if the type T is a task T, then the
3480 -- first argument to Init must be converted to the task record type.
3483 T
: constant Entity_Id
:= Entity
(Expression
(N
));
3491 Temp_Decl
: Node_Id
;
3492 Temp_Type
: Entity_Id
;
3493 Attach_Level
: Uint
;
3496 if No_Initialization
(N
) then
3499 -- Case of no initialization procedure present
3501 elsif not Has_Non_Null_Base_Init_Proc
(T
) then
3503 -- Case of simple initialization required
3505 if Needs_Simple_Initialization
(T
) then
3506 Check_Restriction
(No_Default_Initialization
, N
);
3507 Rewrite
(Expression
(N
),
3508 Make_Qualified_Expression
(Loc
,
3509 Subtype_Mark
=> New_Occurrence_Of
(T
, Loc
),
3510 Expression
=> Get_Simple_Init_Val
(T
, N
)));
3512 Analyze_And_Resolve
(Expression
(Expression
(N
)), T
);
3513 Analyze_And_Resolve
(Expression
(N
), T
);
3514 Set_Paren_Count
(Expression
(Expression
(N
)), 1);
3515 Expand_N_Allocator
(N
);
3517 -- No initialization required
3523 -- Case of initialization procedure present, must be called
3526 Check_Restriction
(No_Default_Initialization
, N
);
3528 if not Restriction_Active
(No_Default_Initialization
) then
3529 Init
:= Base_Init_Proc
(T
);
3531 Temp
:= Make_Defining_Identifier
(Loc
, New_Internal_Name
('P'));
3533 -- Construct argument list for the initialization routine call
3536 Make_Explicit_Dereference
(Loc
,
3537 Prefix
=> New_Reference_To
(Temp
, Loc
));
3538 Set_Assignment_OK
(Arg1
);
3541 -- The initialization procedure expects a specific type. if the
3542 -- context is access to class wide, indicate that the object
3543 -- being allocated has the right specific type.
3545 if Is_Class_Wide_Type
(Dtyp
) then
3546 Arg1
:= Unchecked_Convert_To
(T
, Arg1
);
3549 -- If designated type is a concurrent type or if it is private
3550 -- type whose definition is a concurrent type, the first
3551 -- argument in the Init routine has to be unchecked conversion
3552 -- to the corresponding record type. If the designated type is
3553 -- a derived type, we also convert the argument to its root
3556 if Is_Concurrent_Type
(T
) then
3558 Unchecked_Convert_To
(Corresponding_Record_Type
(T
), Arg1
);
3560 elsif Is_Private_Type
(T
)
3561 and then Present
(Full_View
(T
))
3562 and then Is_Concurrent_Type
(Full_View
(T
))
3565 Unchecked_Convert_To
3566 (Corresponding_Record_Type
(Full_View
(T
)), Arg1
);
3568 elsif Etype
(First_Formal
(Init
)) /= Base_Type
(T
) then
3570 Ftyp
: constant Entity_Id
:= Etype
(First_Formal
(Init
));
3572 Arg1
:= OK_Convert_To
(Etype
(Ftyp
), Arg1
);
3573 Set_Etype
(Arg1
, Ftyp
);
3577 Args
:= New_List
(Arg1
);
3579 -- For the task case, pass the Master_Id of the access type as
3580 -- the value of the _Master parameter, and _Chain as the value
3581 -- of the _Chain parameter (_Chain will be defined as part of
3582 -- the generated code for the allocator).
3584 -- In Ada 2005, the context may be a function that returns an
3585 -- anonymous access type. In that case the Master_Id has been
3586 -- created when expanding the function declaration.
3588 if Has_Task
(T
) then
3589 if No
(Master_Id
(Base_Type
(PtrT
))) then
3591 -- If we have a non-library level task with restriction
3592 -- No_Task_Hierarchy set, then no point in expanding.
3594 if not Is_Library_Level_Entity
(T
)
3595 and then Restriction_Active
(No_Task_Hierarchy
)
3600 -- The designated type was an incomplete type, and the
3601 -- access type did not get expanded. Salvage it now.
3603 pragma Assert
(Present
(Parent
(Base_Type
(PtrT
))));
3604 Expand_N_Full_Type_Declaration
3605 (Parent
(Base_Type
(PtrT
)));
3608 -- If the context of the allocator is a declaration or an
3609 -- assignment, we can generate a meaningful image for it,
3610 -- even though subsequent assignments might remove the
3611 -- connection between task and entity. We build this image
3612 -- when the left-hand side is a simple variable, a simple
3613 -- indexed assignment or a simple selected component.
3615 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
3617 Nam
: constant Node_Id
:= Name
(Parent
(N
));
3620 if Is_Entity_Name
(Nam
) then
3622 Build_Task_Image_Decls
3625 (Entity
(Nam
), Sloc
(Nam
)), T
);
3628 (Nam
, N_Indexed_Component
, N_Selected_Component
)
3629 and then Is_Entity_Name
(Prefix
(Nam
))
3632 Build_Task_Image_Decls
3633 (Loc
, Nam
, Etype
(Prefix
(Nam
)));
3635 Decls
:= Build_Task_Image_Decls
(Loc
, T
, T
);
3639 elsif Nkind
(Parent
(N
)) = N_Object_Declaration
then
3641 Build_Task_Image_Decls
3642 (Loc
, Defining_Identifier
(Parent
(N
)), T
);
3645 Decls
:= Build_Task_Image_Decls
(Loc
, T
, T
);
3650 (Master_Id
(Base_Type
(Root_Type
(PtrT
))), Loc
));
3651 Append_To
(Args
, Make_Identifier
(Loc
, Name_uChain
));
3653 Decl
:= Last
(Decls
);
3655 New_Occurrence_Of
(Defining_Identifier
(Decl
), Loc
));
3657 -- Has_Task is false, Decls not used
3663 -- Add discriminants if discriminated type
3666 Dis
: Boolean := False;
3670 if Has_Discriminants
(T
) then
3674 elsif Is_Private_Type
(T
)
3675 and then Present
(Full_View
(T
))
3676 and then Has_Discriminants
(Full_View
(T
))
3679 Typ
:= Full_View
(T
);
3684 -- If the allocated object will be constrained by the
3685 -- default values for discriminants, then build a subtype
3686 -- with those defaults, and change the allocated subtype
3687 -- to that. Note that this happens in fewer cases in Ada
3690 if not Is_Constrained
(Typ
)
3691 and then Present
(Discriminant_Default_Value
3692 (First_Discriminant
(Typ
)))
3693 and then (Ada_Version
< Ada_05
3695 not Has_Constrained_Partial_View
(Typ
))
3697 Typ
:= Build_Default_Subtype
(Typ
, N
);
3698 Set_Expression
(N
, New_Reference_To
(Typ
, Loc
));
3701 Discr
:= First_Elmt
(Discriminant_Constraint
(Typ
));
3702 while Present
(Discr
) loop
3703 Nod
:= Node
(Discr
);
3704 Append
(New_Copy_Tree
(Node
(Discr
)), Args
);
3706 -- AI-416: when the discriminant constraint is an
3707 -- anonymous access type make sure an accessibility
3708 -- check is inserted if necessary (3.10.2(22.q/2))
3710 if Ada_Version
>= Ada_05
3712 Ekind
(Etype
(Nod
)) = E_Anonymous_Access_Type
3714 Apply_Accessibility_Check
3715 (Nod
, Typ
, Insert_Node
=> Nod
);
3723 -- We set the allocator as analyzed so that when we analyze the
3724 -- expression actions node, we do not get an unwanted recursive
3725 -- expansion of the allocator expression.
3727 Set_Analyzed
(N
, True);
3728 Nod
:= Relocate_Node
(N
);
3730 -- Here is the transformation:
3732 -- output: Temp : constant ptr_T := new T;
3733 -- Init (Temp.all, ...);
3734 -- <CTRL> Attach_To_Final_List (Finalizable (Temp.all));
3735 -- <CTRL> Initialize (Finalizable (Temp.all));
3737 -- Here ptr_T is the pointer type for the allocator, and is the
3738 -- subtype of the allocator.
3741 Make_Object_Declaration
(Loc
,
3742 Defining_Identifier
=> Temp
,
3743 Constant_Present
=> True,
3744 Object_Definition
=> New_Reference_To
(Temp_Type
, Loc
),
3747 Set_Assignment_OK
(Temp_Decl
);
3748 Insert_Action
(N
, Temp_Decl
, Suppress
=> All_Checks
);
3750 -- If the designated type is a task type or contains tasks,
3751 -- create block to activate created tasks, and insert
3752 -- declaration for Task_Image variable ahead of call.
3754 if Has_Task
(T
) then
3756 L
: constant List_Id
:= New_List
;
3759 Build_Task_Allocate_Block
(L
, Nod
, Args
);
3761 Insert_List_Before
(First
(Declarations
(Blk
)), Decls
);
3762 Insert_Actions
(N
, L
);
3767 Make_Procedure_Call_Statement
(Loc
,
3768 Name
=> New_Reference_To
(Init
, Loc
),
3769 Parameter_Associations
=> Args
));
3772 if Needs_Finalization
(T
) then
3774 -- Postpone the generation of a finalization call for the
3775 -- current allocator if it acts as a coextension.
3777 if Is_Dynamic_Coextension
(N
) then
3778 if No
(Coextensions
(N
)) then
3779 Set_Coextensions
(N
, New_Elmt_List
);
3782 Append_Elmt
(New_Copy_Tree
(Arg1
), Coextensions
(N
));
3786 Get_Allocator_Final_List
(N
, Base_Type
(T
), PtrT
);
3788 -- Anonymous access types created for access parameters
3789 -- are attached to an explicitly constructed controller,
3790 -- which ensures that they can be finalized properly,
3791 -- even if their deallocation might not happen. The list
3792 -- associated with the controller is doubly-linked. For
3793 -- other anonymous access types, the object may end up
3794 -- on the global final list which is singly-linked.
3795 -- Work needed for access discriminants in Ada 2005 ???
3797 if Ekind
(PtrT
) = E_Anonymous_Access_Type
then
3798 Attach_Level
:= Uint_1
;
3800 Attach_Level
:= Uint_2
;
3805 Ref
=> New_Copy_Tree
(Arg1
),
3808 With_Attach
=> Make_Integer_Literal
(Loc
,
3809 Intval
=> Attach_Level
)));
3813 Rewrite
(N
, New_Reference_To
(Temp
, Loc
));
3814 Analyze_And_Resolve
(N
, PtrT
);
3819 -- Ada 2005 (AI-251): If the allocator is for a class-wide interface
3820 -- object that has been rewritten as a reference, we displace "this"
3821 -- to reference properly its secondary dispatch table.
3823 if Nkind
(N
) = N_Identifier
3824 and then Is_Interface
(Dtyp
)
3826 Displace_Allocator_Pointer
(N
);
3830 when RE_Not_Available
=>
3832 end Expand_N_Allocator
;
3834 -----------------------
3835 -- Expand_N_And_Then --
3836 -----------------------
3838 -- Expand into conditional expression if Actions present, and also deal
3839 -- with optimizing case of arguments being True or False.
3841 procedure Expand_N_And_Then
(N
: Node_Id
) is
3842 Loc
: constant Source_Ptr
:= Sloc
(N
);
3843 Typ
: constant Entity_Id
:= Etype
(N
);
3844 Left
: constant Node_Id
:= Left_Opnd
(N
);
3845 Right
: constant Node_Id
:= Right_Opnd
(N
);
3849 -- Deal with non-standard booleans
3851 if Is_Boolean_Type
(Typ
) then
3852 Adjust_Condition
(Left
);
3853 Adjust_Condition
(Right
);
3854 Set_Etype
(N
, Standard_Boolean
);
3857 -- Check for cases where left argument is known to be True or False
3859 if Compile_Time_Known_Value
(Left
) then
3861 -- If left argument is True, change (True and then Right) to Right.
3862 -- Any actions associated with Right will be executed unconditionally
3863 -- and can thus be inserted into the tree unconditionally.
3865 if Expr_Value_E
(Left
) = Standard_True
then
3866 if Present
(Actions
(N
)) then
3867 Insert_Actions
(N
, Actions
(N
));
3872 -- If left argument is False, change (False and then Right) to False.
3873 -- In this case we can forget the actions associated with Right,
3874 -- since they will never be executed.
3876 else pragma Assert
(Expr_Value_E
(Left
) = Standard_False
);
3877 Kill_Dead_Code
(Right
);
3878 Kill_Dead_Code
(Actions
(N
));
3879 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
3882 Adjust_Result_Type
(N
, Typ
);
3886 -- If Actions are present, we expand
3888 -- left and then right
3892 -- if left then right else false end
3894 -- with the actions becoming the Then_Actions of the conditional
3895 -- expression. This conditional expression is then further expanded
3896 -- (and will eventually disappear)
3898 if Present
(Actions
(N
)) then
3899 Actlist
:= Actions
(N
);
3901 Make_Conditional_Expression
(Loc
,
3902 Expressions
=> New_List
(
3905 New_Occurrence_Of
(Standard_False
, Loc
))));
3907 Set_Then_Actions
(N
, Actlist
);
3908 Analyze_And_Resolve
(N
, Standard_Boolean
);
3909 Adjust_Result_Type
(N
, Typ
);
3913 -- No actions present, check for cases of right argument True/False
3915 if Compile_Time_Known_Value
(Right
) then
3917 -- Change (Left and then True) to Left. Note that we know there are
3918 -- no actions associated with the True operand, since we just checked
3919 -- for this case above.
3921 if Expr_Value_E
(Right
) = Standard_True
then
3924 -- Change (Left and then False) to False, making sure to preserve any
3925 -- side effects associated with the Left operand.
3927 else pragma Assert
(Expr_Value_E
(Right
) = Standard_False
);
3928 Remove_Side_Effects
(Left
);
3930 (N
, New_Occurrence_Of
(Standard_False
, Loc
));
3934 Adjust_Result_Type
(N
, Typ
);
3935 end Expand_N_And_Then
;
3937 -------------------------------------
3938 -- Expand_N_Conditional_Expression --
3939 -------------------------------------
3941 -- Expand into expression actions if then/else actions present
3943 procedure Expand_N_Conditional_Expression
(N
: Node_Id
) is
3944 Loc
: constant Source_Ptr
:= Sloc
(N
);
3945 Cond
: constant Node_Id
:= First
(Expressions
(N
));
3946 Thenx
: constant Node_Id
:= Next
(Cond
);
3947 Elsex
: constant Node_Id
:= Next
(Thenx
);
3948 Typ
: constant Entity_Id
:= Etype
(N
);
3953 -- If either then or else actions are present, then given:
3955 -- if cond then then-expr else else-expr end
3957 -- we insert the following sequence of actions (using Insert_Actions):
3962 -- Cnn := then-expr;
3968 -- and replace the conditional expression by a reference to Cnn
3970 if Present
(Then_Actions
(N
)) or else Present
(Else_Actions
(N
)) then
3971 Cnn
:= Make_Defining_Identifier
(Loc
, New_Internal_Name
('C'));
3974 Make_Implicit_If_Statement
(N
,
3975 Condition
=> Relocate_Node
(Cond
),
3977 Then_Statements
=> New_List
(
3978 Make_Assignment_Statement
(Sloc
(Thenx
),
3979 Name
=> New_Occurrence_Of
(Cnn
, Sloc
(Thenx
)),
3980 Expression
=> Relocate_Node
(Thenx
))),
3982 Else_Statements
=> New_List
(
3983 Make_Assignment_Statement
(Sloc
(Elsex
),
3984 Name
=> New_Occurrence_Of
(Cnn
, Sloc
(Elsex
)),
3985 Expression
=> Relocate_Node
(Elsex
))));
3987 -- Move the SLOC of the parent If statement to the newly created
3988 -- one and change it to the SLOC of the expression which, after
3989 -- expansion, will correspond to what is being evaluated.
3991 if Present
(Parent
(N
))
3992 and then Nkind
(Parent
(N
)) = N_If_Statement
3994 Set_Sloc
(New_If
, Sloc
(Parent
(N
)));
3995 Set_Sloc
(Parent
(N
), Loc
);
3998 Set_Assignment_OK
(Name
(First
(Then_Statements
(New_If
))));
3999 Set_Assignment_OK
(Name
(First
(Else_Statements
(New_If
))));
4001 if Present
(Then_Actions
(N
)) then
4003 (First
(Then_Statements
(New_If
)), Then_Actions
(N
));
4006 if Present
(Else_Actions
(N
)) then
4008 (First
(Else_Statements
(New_If
)), Else_Actions
(N
));
4011 Rewrite
(N
, New_Occurrence_Of
(Cnn
, Loc
));
4014 Make_Object_Declaration
(Loc
,
4015 Defining_Identifier
=> Cnn
,
4016 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
)));
4018 Insert_Action
(N
, New_If
);
4019 Analyze_And_Resolve
(N
, Typ
);
4021 end Expand_N_Conditional_Expression
;
4023 -----------------------------------
4024 -- Expand_N_Explicit_Dereference --
4025 -----------------------------------
4027 procedure Expand_N_Explicit_Dereference
(N
: Node_Id
) is
4029 -- Insert explicit dereference call for the checked storage pool case
4031 Insert_Dereference_Action
(Prefix
(N
));
4032 end Expand_N_Explicit_Dereference
;
4038 procedure Expand_N_In
(N
: Node_Id
) is
4039 Loc
: constant Source_Ptr
:= Sloc
(N
);
4040 Rtyp
: constant Entity_Id
:= Etype
(N
);
4041 Lop
: constant Node_Id
:= Left_Opnd
(N
);
4042 Rop
: constant Node_Id
:= Right_Opnd
(N
);
4043 Static
: constant Boolean := Is_OK_Static_Expression
(N
);
4045 procedure Substitute_Valid_Check
;
4046 -- Replaces node N by Lop'Valid. This is done when we have an explicit
4047 -- test for the left operand being in range of its subtype.
4049 ----------------------------
4050 -- Substitute_Valid_Check --
4051 ----------------------------
4053 procedure Substitute_Valid_Check
is
4056 Make_Attribute_Reference
(Loc
,
4057 Prefix
=> Relocate_Node
(Lop
),
4058 Attribute_Name
=> Name_Valid
));
4060 Analyze_And_Resolve
(N
, Rtyp
);
4062 Error_Msg_N
("?explicit membership test may be optimized away", N
);
4063 Error_Msg_N
("\?use ''Valid attribute instead", N
);
4065 end Substitute_Valid_Check
;
4067 -- Start of processing for Expand_N_In
4070 -- Check case of explicit test for an expression in range of its
4071 -- subtype. This is suspicious usage and we replace it with a 'Valid
4072 -- test and give a warning.
4074 if Is_Scalar_Type
(Etype
(Lop
))
4075 and then Nkind
(Rop
) in N_Has_Entity
4076 and then Etype
(Lop
) = Entity
(Rop
)
4077 and then Comes_From_Source
(N
)
4078 and then VM_Target
= No_VM
4080 Substitute_Valid_Check
;
4084 -- Do validity check on operands
4086 if Validity_Checks_On
and Validity_Check_Operands
then
4087 Ensure_Valid
(Left_Opnd
(N
));
4088 Validity_Check_Range
(Right_Opnd
(N
));
4091 -- Case of explicit range
4093 if Nkind
(Rop
) = N_Range
then
4095 Lo
: constant Node_Id
:= Low_Bound
(Rop
);
4096 Hi
: constant Node_Id
:= High_Bound
(Rop
);
4098 Ltyp
: constant Entity_Id
:= Etype
(Lop
);
4100 Lo_Orig
: constant Node_Id
:= Original_Node
(Lo
);
4101 Hi_Orig
: constant Node_Id
:= Original_Node
(Hi
);
4103 Lcheck
: Compare_Result
;
4104 Ucheck
: Compare_Result
;
4106 Warn1
: constant Boolean :=
4107 Constant_Condition_Warnings
4108 and then Comes_From_Source
(N
)
4109 and then not In_Instance
;
4110 -- This must be true for any of the optimization warnings, we
4111 -- clearly want to give them only for source with the flag on.
4112 -- We also skip these warnings in an instance since it may be
4113 -- the case that different instantiations have different ranges.
4115 Warn2
: constant Boolean :=
4117 and then Nkind
(Original_Node
(Rop
)) = N_Range
4118 and then Is_Integer_Type
(Etype
(Lo
));
4119 -- For the case where only one bound warning is elided, we also
4120 -- insist on an explicit range and an integer type. The reason is
4121 -- that the use of enumeration ranges including an end point is
4122 -- common, as is the use of a subtype name, one of whose bounds
4123 -- is the same as the type of the expression.
4126 -- If test is explicit x'first .. x'last, replace by valid check
4128 if Is_Scalar_Type
(Ltyp
)
4129 and then Nkind
(Lo_Orig
) = N_Attribute_Reference
4130 and then Attribute_Name
(Lo_Orig
) = Name_First
4131 and then Nkind
(Prefix
(Lo_Orig
)) in N_Has_Entity
4132 and then Entity
(Prefix
(Lo_Orig
)) = Ltyp
4133 and then Nkind
(Hi_Orig
) = N_Attribute_Reference
4134 and then Attribute_Name
(Hi_Orig
) = Name_Last
4135 and then Nkind
(Prefix
(Hi_Orig
)) in N_Has_Entity
4136 and then Entity
(Prefix
(Hi_Orig
)) = Ltyp
4137 and then Comes_From_Source
(N
)
4138 and then VM_Target
= No_VM
4140 Substitute_Valid_Check
;
4144 -- If bounds of type are known at compile time, and the end points
4145 -- are known at compile time and identical, this is another case
4146 -- for substituting a valid test. We only do this for discrete
4147 -- types, since it won't arise in practice for float types.
4149 if Comes_From_Source
(N
)
4150 and then Is_Discrete_Type
(Ltyp
)
4151 and then Compile_Time_Known_Value
(Type_High_Bound
(Ltyp
))
4152 and then Compile_Time_Known_Value
(Type_Low_Bound
(Ltyp
))
4153 and then Compile_Time_Known_Value
(Lo
)
4154 and then Compile_Time_Known_Value
(Hi
)
4155 and then Expr_Value
(Type_High_Bound
(Ltyp
)) = Expr_Value
(Hi
)
4156 and then Expr_Value
(Type_Low_Bound
(Ltyp
)) = Expr_Value
(Lo
)
4158 -- Kill warnings in instances, since they may be cases where we
4159 -- have a test in the generic that makes sense with some types
4160 -- and not with other types.
4162 and then not In_Instance
4164 Substitute_Valid_Check
;
4168 -- If we have an explicit range, do a bit of optimization based
4169 -- on range analysis (we may be able to kill one or both checks).
4171 Lcheck
:= Compile_Time_Compare
(Lop
, Lo
, Assume_Valid
=> False);
4172 Ucheck
:= Compile_Time_Compare
(Lop
, Hi
, Assume_Valid
=> False);
4174 -- If either check is known to fail, replace result by False since
4175 -- the other check does not matter. Preserve the static flag for
4176 -- legality checks, because we are constant-folding beyond RM 4.9.
4178 if Lcheck
= LT
or else Ucheck
= GT
then
4180 Error_Msg_N
("?range test optimized away", N
);
4181 Error_Msg_N
("\?value is known to be out of range", N
);
4185 New_Reference_To
(Standard_False
, Loc
));
4186 Analyze_And_Resolve
(N
, Rtyp
);
4187 Set_Is_Static_Expression
(N
, Static
);
4191 -- If both checks are known to succeed, replace result by True,
4192 -- since we know we are in range.
4194 elsif Lcheck
in Compare_GE
and then Ucheck
in Compare_LE
then
4196 Error_Msg_N
("?range test optimized away", N
);
4197 Error_Msg_N
("\?value is known to be in range", N
);
4201 New_Reference_To
(Standard_True
, Loc
));
4202 Analyze_And_Resolve
(N
, Rtyp
);
4203 Set_Is_Static_Expression
(N
, Static
);
4207 -- If lower bound check succeeds and upper bound check is not
4208 -- known to succeed or fail, then replace the range check with
4209 -- a comparison against the upper bound.
4211 elsif Lcheck
in Compare_GE
then
4212 if Warn2
and then not In_Instance
then
4213 Error_Msg_N
("?lower bound test optimized away", Lo
);
4214 Error_Msg_N
("\?value is known to be in range", Lo
);
4220 Right_Opnd
=> High_Bound
(Rop
)));
4221 Analyze_And_Resolve
(N
, Rtyp
);
4225 -- If upper bound check succeeds and lower bound check is not
4226 -- known to succeed or fail, then replace the range check with
4227 -- a comparison against the lower bound.
4229 elsif Ucheck
in Compare_LE
then
4230 if Warn2
and then not In_Instance
then
4231 Error_Msg_N
("?upper bound test optimized away", Hi
);
4232 Error_Msg_N
("\?value is known to be in range", Hi
);
4238 Right_Opnd
=> Low_Bound
(Rop
)));
4239 Analyze_And_Resolve
(N
, Rtyp
);
4244 -- We couldn't optimize away the range check, but there is one
4245 -- more issue. If we are checking constant conditionals, then we
4246 -- see if we can determine the outcome assuming everything is
4247 -- valid, and if so give an appropriate warning.
4249 if Warn1
and then not Assume_No_Invalid_Values
then
4250 Lcheck
:= Compile_Time_Compare
(Lop
, Lo
, Assume_Valid
=> True);
4251 Ucheck
:= Compile_Time_Compare
(Lop
, Hi
, Assume_Valid
=> True);
4253 -- Result is out of range for valid value
4255 if Lcheck
= LT
or else Ucheck
= GT
then
4257 ("?value can only be in range if it is invalid", N
);
4259 -- Result is in range for valid value
4261 elsif Lcheck
in Compare_GE
and then Ucheck
in Compare_LE
then
4263 ("?value can only be out of range if it is invalid", N
);
4265 -- Lower bound check succeeds if value is valid
4267 elsif Warn2
and then Lcheck
in Compare_GE
then
4269 ("?lower bound check only fails if it is invalid", Lo
);
4271 -- Upper bound check succeeds if value is valid
4273 elsif Warn2
and then Ucheck
in Compare_LE
then
4275 ("?upper bound check only fails for invalid values", Hi
);
4280 -- For all other cases of an explicit range, nothing to be done
4284 -- Here right operand is a subtype mark
4288 Typ
: Entity_Id
:= Etype
(Rop
);
4289 Is_Acc
: constant Boolean := Is_Access_Type
(Typ
);
4290 Obj
: Node_Id
:= Lop
;
4291 Cond
: Node_Id
:= Empty
;
4294 Remove_Side_Effects
(Obj
);
4296 -- For tagged type, do tagged membership operation
4298 if Is_Tagged_Type
(Typ
) then
4300 -- No expansion will be performed when VM_Target, as the VM
4301 -- back-ends will handle the membership tests directly (tags
4302 -- are not explicitly represented in Java objects, so the
4303 -- normal tagged membership expansion is not what we want).
4305 if Tagged_Type_Expansion
then
4306 Rewrite
(N
, Tagged_Membership
(N
));
4307 Analyze_And_Resolve
(N
, Rtyp
);
4312 -- If type is scalar type, rewrite as x in t'first .. t'last.
4313 -- This reason we do this is that the bounds may have the wrong
4314 -- type if they come from the original type definition. Also this
4315 -- way we get all the processing above for an explicit range.
4317 elsif Is_Scalar_Type
(Typ
) then
4321 Make_Attribute_Reference
(Loc
,
4322 Attribute_Name
=> Name_First
,
4323 Prefix
=> New_Reference_To
(Typ
, Loc
)),
4326 Make_Attribute_Reference
(Loc
,
4327 Attribute_Name
=> Name_Last
,
4328 Prefix
=> New_Reference_To
(Typ
, Loc
))));
4329 Analyze_And_Resolve
(N
, Rtyp
);
4332 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
4333 -- a membership test if the subtype mark denotes a constrained
4334 -- Unchecked_Union subtype and the expression lacks inferable
4337 elsif Is_Unchecked_Union
(Base_Type
(Typ
))
4338 and then Is_Constrained
(Typ
)
4339 and then not Has_Inferable_Discriminants
(Lop
)
4342 Make_Raise_Program_Error
(Loc
,
4343 Reason
=> PE_Unchecked_Union_Restriction
));
4345 -- Prevent Gigi from generating incorrect code by rewriting
4346 -- the test as a standard False.
4349 New_Occurrence_Of
(Standard_False
, Loc
));
4354 -- Here we have a non-scalar type
4357 Typ
:= Designated_Type
(Typ
);
4360 if not Is_Constrained
(Typ
) then
4362 New_Reference_To
(Standard_True
, Loc
));
4363 Analyze_And_Resolve
(N
, Rtyp
);
4365 -- For the constrained array case, we have to check the subscripts
4366 -- for an exact match if the lengths are non-zero (the lengths
4367 -- must match in any case).
4369 elsif Is_Array_Type
(Typ
) then
4371 Check_Subscripts
: declare
4372 function Construct_Attribute_Reference
4375 Dim
: Nat
) return Node_Id
;
4376 -- Build attribute reference E'Nam(Dim)
4378 -----------------------------------
4379 -- Construct_Attribute_Reference --
4380 -----------------------------------
4382 function Construct_Attribute_Reference
4385 Dim
: Nat
) return Node_Id
4389 Make_Attribute_Reference
(Loc
,
4391 Attribute_Name
=> Nam
,
4392 Expressions
=> New_List
(
4393 Make_Integer_Literal
(Loc
, Dim
)));
4394 end Construct_Attribute_Reference
;
4396 -- Start of processing for Check_Subscripts
4399 for J
in 1 .. Number_Dimensions
(Typ
) loop
4400 Evolve_And_Then
(Cond
,
4403 Construct_Attribute_Reference
4404 (Duplicate_Subexpr_No_Checks
(Obj
),
4407 Construct_Attribute_Reference
4408 (New_Occurrence_Of
(Typ
, Loc
), Name_First
, J
)));
4410 Evolve_And_Then
(Cond
,
4413 Construct_Attribute_Reference
4414 (Duplicate_Subexpr_No_Checks
(Obj
),
4417 Construct_Attribute_Reference
4418 (New_Occurrence_Of
(Typ
, Loc
), Name_Last
, J
)));
4427 Right_Opnd
=> Make_Null
(Loc
)),
4428 Right_Opnd
=> Cond
);
4432 Analyze_And_Resolve
(N
, Rtyp
);
4433 end Check_Subscripts
;
4435 -- These are the cases where constraint checks may be required,
4436 -- e.g. records with possible discriminants
4439 -- Expand the test into a series of discriminant comparisons.
4440 -- The expression that is built is the negation of the one that
4441 -- is used for checking discriminant constraints.
4443 Obj
:= Relocate_Node
(Left_Opnd
(N
));
4445 if Has_Discriminants
(Typ
) then
4446 Cond
:= Make_Op_Not
(Loc
,
4447 Right_Opnd
=> Build_Discriminant_Checks
(Obj
, Typ
));
4450 Cond
:= Make_Or_Else
(Loc
,
4454 Right_Opnd
=> Make_Null
(Loc
)),
4455 Right_Opnd
=> Cond
);
4459 Cond
:= New_Occurrence_Of
(Standard_True
, Loc
);
4463 Analyze_And_Resolve
(N
, Rtyp
);
4469 --------------------------------
4470 -- Expand_N_Indexed_Component --
4471 --------------------------------
4473 procedure Expand_N_Indexed_Component
(N
: Node_Id
) is
4474 Loc
: constant Source_Ptr
:= Sloc
(N
);
4475 Typ
: constant Entity_Id
:= Etype
(N
);
4476 P
: constant Node_Id
:= Prefix
(N
);
4477 T
: constant Entity_Id
:= Etype
(P
);
4480 -- A special optimization, if we have an indexed component that is
4481 -- selecting from a slice, then we can eliminate the slice, since, for
4482 -- example, x (i .. j)(k) is identical to x(k). The only difference is
4483 -- the range check required by the slice. The range check for the slice
4484 -- itself has already been generated. The range check for the
4485 -- subscripting operation is ensured by converting the subject to
4486 -- the subtype of the slice.
4488 -- This optimization not only generates better code, avoiding slice
4489 -- messing especially in the packed case, but more importantly bypasses
4490 -- some problems in handling this peculiar case, for example, the issue
4491 -- of dealing specially with object renamings.
4493 if Nkind
(P
) = N_Slice
then
4495 Make_Indexed_Component
(Loc
,
4496 Prefix
=> Prefix
(P
),
4497 Expressions
=> New_List
(
4499 (Etype
(First_Index
(Etype
(P
))),
4500 First
(Expressions
(N
))))));
4501 Analyze_And_Resolve
(N
, Typ
);
4505 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
4506 -- function, then additional actuals must be passed.
4508 if Ada_Version
>= Ada_05
4509 and then Is_Build_In_Place_Function_Call
(P
)
4511 Make_Build_In_Place_Call_In_Anonymous_Context
(P
);
4514 -- If the prefix is an access type, then we unconditionally rewrite if
4515 -- as an explicit deference. This simplifies processing for several
4516 -- cases, including packed array cases and certain cases in which checks
4517 -- must be generated. We used to try to do this only when it was
4518 -- necessary, but it cleans up the code to do it all the time.
4520 if Is_Access_Type
(T
) then
4521 Insert_Explicit_Dereference
(P
);
4522 Analyze_And_Resolve
(P
, Designated_Type
(T
));
4525 -- Generate index and validity checks
4527 Generate_Index_Checks
(N
);
4529 if Validity_Checks_On
and then Validity_Check_Subscripts
then
4530 Apply_Subscript_Validity_Checks
(N
);
4533 -- All done for the non-packed case
4535 if not Is_Packed
(Etype
(Prefix
(N
))) then
4539 -- For packed arrays that are not bit-packed (i.e. the case of an array
4540 -- with one or more index types with a non-contiguous enumeration type),
4541 -- we can always use the normal packed element get circuit.
4543 if not Is_Bit_Packed_Array
(Etype
(Prefix
(N
))) then
4544 Expand_Packed_Element_Reference
(N
);
4548 -- For a reference to a component of a bit packed array, we have to
4549 -- convert it to a reference to the corresponding Packed_Array_Type.
4550 -- We only want to do this for simple references, and not for:
4552 -- Left side of assignment, or prefix of left side of assignment, or
4553 -- prefix of the prefix, to handle packed arrays of packed arrays,
4554 -- This case is handled in Exp_Ch5.Expand_N_Assignment_Statement
4556 -- Renaming objects in renaming associations
4557 -- This case is handled when a use of the renamed variable occurs
4559 -- Actual parameters for a procedure call
4560 -- This case is handled in Exp_Ch6.Expand_Actuals
4562 -- The second expression in a 'Read attribute reference
4564 -- The prefix of an address or size attribute reference
4566 -- The following circuit detects these exceptions
4569 Child
: Node_Id
:= N
;
4570 Parnt
: Node_Id
:= Parent
(N
);
4574 if Nkind
(Parnt
) = N_Unchecked_Expression
then
4577 elsif Nkind_In
(Parnt
, N_Object_Renaming_Declaration
,
4578 N_Procedure_Call_Statement
)
4579 or else (Nkind
(Parnt
) = N_Parameter_Association
4581 Nkind
(Parent
(Parnt
)) = N_Procedure_Call_Statement
)
4585 elsif Nkind
(Parnt
) = N_Attribute_Reference
4586 and then (Attribute_Name
(Parnt
) = Name_Address
4588 Attribute_Name
(Parnt
) = Name_Size
)
4589 and then Prefix
(Parnt
) = Child
4593 elsif Nkind
(Parnt
) = N_Assignment_Statement
4594 and then Name
(Parnt
) = Child
4598 -- If the expression is an index of an indexed component, it must
4599 -- be expanded regardless of context.
4601 elsif Nkind
(Parnt
) = N_Indexed_Component
4602 and then Child
/= Prefix
(Parnt
)
4604 Expand_Packed_Element_Reference
(N
);
4607 elsif Nkind
(Parent
(Parnt
)) = N_Assignment_Statement
4608 and then Name
(Parent
(Parnt
)) = Parnt
4612 elsif Nkind
(Parnt
) = N_Attribute_Reference
4613 and then Attribute_Name
(Parnt
) = Name_Read
4614 and then Next
(First
(Expressions
(Parnt
))) = Child
4618 elsif Nkind_In
(Parnt
, N_Indexed_Component
, N_Selected_Component
)
4619 and then Prefix
(Parnt
) = Child
4624 Expand_Packed_Element_Reference
(N
);
4628 -- Keep looking up tree for unchecked expression, or if we are the
4629 -- prefix of a possible assignment left side.
4632 Parnt
:= Parent
(Child
);
4635 end Expand_N_Indexed_Component
;
4637 ---------------------
4638 -- Expand_N_Not_In --
4639 ---------------------
4641 -- Replace a not in b by not (a in b) so that the expansions for (a in b)
4642 -- can be done. This avoids needing to duplicate this expansion code.
4644 procedure Expand_N_Not_In
(N
: Node_Id
) is
4645 Loc
: constant Source_Ptr
:= Sloc
(N
);
4646 Typ
: constant Entity_Id
:= Etype
(N
);
4647 Cfs
: constant Boolean := Comes_From_Source
(N
);
4654 Left_Opnd
=> Left_Opnd
(N
),
4655 Right_Opnd
=> Right_Opnd
(N
))));
4657 -- We want this to appear as coming from source if original does (see
4658 -- transformations in Expand_N_In).
4660 Set_Comes_From_Source
(N
, Cfs
);
4661 Set_Comes_From_Source
(Right_Opnd
(N
), Cfs
);
4663 -- Now analyze transformed node
4665 Analyze_And_Resolve
(N
, Typ
);
4666 end Expand_N_Not_In
;
4672 -- The only replacement required is for the case of a null of type that is
4673 -- an access to protected subprogram. We represent such access values as a
4674 -- record, and so we must replace the occurrence of null by the equivalent
4675 -- record (with a null address and a null pointer in it), so that the
4676 -- backend creates the proper value.
4678 procedure Expand_N_Null
(N
: Node_Id
) is
4679 Loc
: constant Source_Ptr
:= Sloc
(N
);
4680 Typ
: constant Entity_Id
:= Etype
(N
);
4684 if Is_Access_Protected_Subprogram_Type
(Typ
) then
4686 Make_Aggregate
(Loc
,
4687 Expressions
=> New_List
(
4688 New_Occurrence_Of
(RTE
(RE_Null_Address
), Loc
),
4692 Analyze_And_Resolve
(N
, Equivalent_Type
(Typ
));
4694 -- For subsequent semantic analysis, the node must retain its type.
4695 -- Gigi in any case replaces this type by the corresponding record
4696 -- type before processing the node.
4702 when RE_Not_Available
=>
4706 ---------------------
4707 -- Expand_N_Op_Abs --
4708 ---------------------
4710 procedure Expand_N_Op_Abs
(N
: Node_Id
) is
4711 Loc
: constant Source_Ptr
:= Sloc
(N
);
4712 Expr
: constant Node_Id
:= Right_Opnd
(N
);
4715 Unary_Op_Validity_Checks
(N
);
4717 -- Deal with software overflow checking
4719 if not Backend_Overflow_Checks_On_Target
4720 and then Is_Signed_Integer_Type
(Etype
(N
))
4721 and then Do_Overflow_Check
(N
)
4723 -- The only case to worry about is when the argument is equal to the
4724 -- largest negative number, so what we do is to insert the check:
4726 -- [constraint_error when Expr = typ'Base'First]
4728 -- with the usual Duplicate_Subexpr use coding for expr
4731 Make_Raise_Constraint_Error
(Loc
,
4734 Left_Opnd
=> Duplicate_Subexpr
(Expr
),
4736 Make_Attribute_Reference
(Loc
,
4738 New_Occurrence_Of
(Base_Type
(Etype
(Expr
)), Loc
),
4739 Attribute_Name
=> Name_First
)),
4740 Reason
=> CE_Overflow_Check_Failed
));
4743 -- Vax floating-point types case
4745 if Vax_Float
(Etype
(N
)) then
4746 Expand_Vax_Arith
(N
);
4748 end Expand_N_Op_Abs
;
4750 ---------------------
4751 -- Expand_N_Op_Add --
4752 ---------------------
4754 procedure Expand_N_Op_Add
(N
: Node_Id
) is
4755 Typ
: constant Entity_Id
:= Etype
(N
);
4758 Binary_Op_Validity_Checks
(N
);
4760 -- N + 0 = 0 + N = N for integer types
4762 if Is_Integer_Type
(Typ
) then
4763 if Compile_Time_Known_Value
(Right_Opnd
(N
))
4764 and then Expr_Value
(Right_Opnd
(N
)) = Uint_0
4766 Rewrite
(N
, Left_Opnd
(N
));
4769 elsif Compile_Time_Known_Value
(Left_Opnd
(N
))
4770 and then Expr_Value
(Left_Opnd
(N
)) = Uint_0
4772 Rewrite
(N
, Right_Opnd
(N
));
4777 -- Arithmetic overflow checks for signed integer/fixed point types
4779 if Is_Signed_Integer_Type
(Typ
)
4780 or else Is_Fixed_Point_Type
(Typ
)
4782 Apply_Arithmetic_Overflow_Check
(N
);
4785 -- Vax floating-point types case
4787 elsif Vax_Float
(Typ
) then
4788 Expand_Vax_Arith
(N
);
4790 end Expand_N_Op_Add
;
4792 ---------------------
4793 -- Expand_N_Op_And --
4794 ---------------------
4796 procedure Expand_N_Op_And
(N
: Node_Id
) is
4797 Typ
: constant Entity_Id
:= Etype
(N
);
4800 Binary_Op_Validity_Checks
(N
);
4802 if Is_Array_Type
(Etype
(N
)) then
4803 Expand_Boolean_Operator
(N
);
4805 elsif Is_Boolean_Type
(Etype
(N
)) then
4806 Adjust_Condition
(Left_Opnd
(N
));
4807 Adjust_Condition
(Right_Opnd
(N
));
4808 Set_Etype
(N
, Standard_Boolean
);
4809 Adjust_Result_Type
(N
, Typ
);
4811 end Expand_N_Op_And
;
4813 ------------------------
4814 -- Expand_N_Op_Concat --
4815 ------------------------
4817 procedure Expand_N_Op_Concat
(N
: Node_Id
) is
4819 -- List of operands to be concatenated
4822 -- Node which is to be replaced by the result of concatenating the nodes
4823 -- in the list Opnds.
4826 -- Ensure validity of both operands
4828 Binary_Op_Validity_Checks
(N
);
4830 -- If we are the left operand of a concatenation higher up the tree,
4831 -- then do nothing for now, since we want to deal with a series of
4832 -- concatenations as a unit.
4834 if Nkind
(Parent
(N
)) = N_Op_Concat
4835 and then N
= Left_Opnd
(Parent
(N
))
4840 -- We get here with a concatenation whose left operand may be a
4841 -- concatenation itself with a consistent type. We need to process
4842 -- these concatenation operands from left to right, which means
4843 -- from the deepest node in the tree to the highest node.
4846 while Nkind
(Left_Opnd
(Cnode
)) = N_Op_Concat
loop
4847 Cnode
:= Left_Opnd
(Cnode
);
4850 -- Now Opnd is the deepest Opnd, and its parents are the concatenation
4851 -- nodes above, so now we process bottom up, doing the operations. We
4852 -- gather a string that is as long as possible up to five operands
4854 -- The outer loop runs more than once if more than one concatenation
4855 -- type is involved.
4858 Opnds
:= New_List
(Left_Opnd
(Cnode
), Right_Opnd
(Cnode
));
4859 Set_Parent
(Opnds
, N
);
4861 -- The inner loop gathers concatenation operands
4863 Inner
: while Cnode
/= N
4864 and then Base_Type
(Etype
(Cnode
)) =
4865 Base_Type
(Etype
(Parent
(Cnode
)))
4867 Cnode
:= Parent
(Cnode
);
4868 Append
(Right_Opnd
(Cnode
), Opnds
);
4871 Expand_Concatenate
(Cnode
, Opnds
);
4873 exit Outer
when Cnode
= N
;
4874 Cnode
:= Parent
(Cnode
);
4876 end Expand_N_Op_Concat
;
4878 ------------------------
4879 -- Expand_N_Op_Divide --
4880 ------------------------
4882 procedure Expand_N_Op_Divide
(N
: Node_Id
) is
4883 Loc
: constant Source_Ptr
:= Sloc
(N
);
4884 Lopnd
: constant Node_Id
:= Left_Opnd
(N
);
4885 Ropnd
: constant Node_Id
:= Right_Opnd
(N
);
4886 Ltyp
: constant Entity_Id
:= Etype
(Lopnd
);
4887 Rtyp
: constant Entity_Id
:= Etype
(Ropnd
);
4888 Typ
: Entity_Id
:= Etype
(N
);
4889 Rknow
: constant Boolean := Is_Integer_Type
(Typ
)
4891 Compile_Time_Known_Value
(Ropnd
);
4895 Binary_Op_Validity_Checks
(N
);
4898 Rval
:= Expr_Value
(Ropnd
);
4901 -- N / 1 = N for integer types
4903 if Rknow
and then Rval
= Uint_1
then
4908 -- Convert x / 2 ** y to Shift_Right (x, y). Note that the fact that
4909 -- Is_Power_Of_2_For_Shift is set means that we know that our left
4910 -- operand is an unsigned integer, as required for this to work.
4912 if Nkind
(Ropnd
) = N_Op_Expon
4913 and then Is_Power_Of_2_For_Shift
(Ropnd
)
4915 -- We cannot do this transformation in configurable run time mode if we
4916 -- have 64-bit -- integers and long shifts are not available.
4920 or else Support_Long_Shifts_On_Target
)
4923 Make_Op_Shift_Right
(Loc
,
4926 Convert_To
(Standard_Natural
, Right_Opnd
(Ropnd
))));
4927 Analyze_And_Resolve
(N
, Typ
);
4931 -- Do required fixup of universal fixed operation
4933 if Typ
= Universal_Fixed
then
4934 Fixup_Universal_Fixed_Operation
(N
);
4938 -- Divisions with fixed-point results
4940 if Is_Fixed_Point_Type
(Typ
) then
4942 -- No special processing if Treat_Fixed_As_Integer is set, since
4943 -- from a semantic point of view such operations are simply integer
4944 -- operations and will be treated that way.
4946 if not Treat_Fixed_As_Integer
(N
) then
4947 if Is_Integer_Type
(Rtyp
) then
4948 Expand_Divide_Fixed_By_Integer_Giving_Fixed
(N
);
4950 Expand_Divide_Fixed_By_Fixed_Giving_Fixed
(N
);
4954 -- Other cases of division of fixed-point operands. Again we exclude the
4955 -- case where Treat_Fixed_As_Integer is set.
4957 elsif (Is_Fixed_Point_Type
(Ltyp
) or else
4958 Is_Fixed_Point_Type
(Rtyp
))
4959 and then not Treat_Fixed_As_Integer
(N
)
4961 if Is_Integer_Type
(Typ
) then
4962 Expand_Divide_Fixed_By_Fixed_Giving_Integer
(N
);
4964 pragma Assert
(Is_Floating_Point_Type
(Typ
));
4965 Expand_Divide_Fixed_By_Fixed_Giving_Float
(N
);
4968 -- Mixed-mode operations can appear in a non-static universal context,
4969 -- in which case the integer argument must be converted explicitly.
4971 elsif Typ
= Universal_Real
4972 and then Is_Integer_Type
(Rtyp
)
4975 Convert_To
(Universal_Real
, Relocate_Node
(Ropnd
)));
4977 Analyze_And_Resolve
(Ropnd
, Universal_Real
);
4979 elsif Typ
= Universal_Real
4980 and then Is_Integer_Type
(Ltyp
)
4983 Convert_To
(Universal_Real
, Relocate_Node
(Lopnd
)));
4985 Analyze_And_Resolve
(Lopnd
, Universal_Real
);
4987 -- Non-fixed point cases, do integer zero divide and overflow checks
4989 elsif Is_Integer_Type
(Typ
) then
4990 Apply_Divide_Check
(N
);
4992 -- Check for 64-bit division available, or long shifts if the divisor
4993 -- is a small power of 2 (since such divides will be converted into
4996 if Esize
(Ltyp
) > 32
4997 and then not Support_64_Bit_Divides_On_Target
5000 or else not Support_Long_Shifts_On_Target
5001 or else (Rval
/= Uint_2
and then
5002 Rval
/= Uint_4
and then
5003 Rval
/= Uint_8
and then
5004 Rval
/= Uint_16
and then
5005 Rval
/= Uint_32
and then
5008 Error_Msg_CRT
("64-bit division", N
);
5011 -- Deal with Vax_Float
5013 elsif Vax_Float
(Typ
) then
5014 Expand_Vax_Arith
(N
);
5017 end Expand_N_Op_Divide
;
5019 --------------------
5020 -- Expand_N_Op_Eq --
5021 --------------------
5023 procedure Expand_N_Op_Eq
(N
: Node_Id
) is
5024 Loc
: constant Source_Ptr
:= Sloc
(N
);
5025 Typ
: constant Entity_Id
:= Etype
(N
);
5026 Lhs
: constant Node_Id
:= Left_Opnd
(N
);
5027 Rhs
: constant Node_Id
:= Right_Opnd
(N
);
5028 Bodies
: constant List_Id
:= New_List
;
5029 A_Typ
: constant Entity_Id
:= Etype
(Lhs
);
5031 Typl
: Entity_Id
:= A_Typ
;
5032 Op_Name
: Entity_Id
;
5035 procedure Build_Equality_Call
(Eq
: Entity_Id
);
5036 -- If a constructed equality exists for the type or for its parent,
5037 -- build and analyze call, adding conversions if the operation is
5040 function Has_Unconstrained_UU_Component
(Typ
: Node_Id
) return Boolean;
5041 -- Determines whether a type has a subcomponent of an unconstrained
5042 -- Unchecked_Union subtype. Typ is a record type.
5044 -------------------------
5045 -- Build_Equality_Call --
5046 -------------------------
5048 procedure Build_Equality_Call
(Eq
: Entity_Id
) is
5049 Op_Type
: constant Entity_Id
:= Etype
(First_Formal
(Eq
));
5050 L_Exp
: Node_Id
:= Relocate_Node
(Lhs
);
5051 R_Exp
: Node_Id
:= Relocate_Node
(Rhs
);
5054 if Base_Type
(Op_Type
) /= Base_Type
(A_Typ
)
5055 and then not Is_Class_Wide_Type
(A_Typ
)
5057 L_Exp
:= OK_Convert_To
(Op_Type
, L_Exp
);
5058 R_Exp
:= OK_Convert_To
(Op_Type
, R_Exp
);
5061 -- If we have an Unchecked_Union, we need to add the inferred
5062 -- discriminant values as actuals in the function call. At this
5063 -- point, the expansion has determined that both operands have
5064 -- inferable discriminants.
5066 if Is_Unchecked_Union
(Op_Type
) then
5068 Lhs_Type
: constant Node_Id
:= Etype
(L_Exp
);
5069 Rhs_Type
: constant Node_Id
:= Etype
(R_Exp
);
5070 Lhs_Discr_Val
: Node_Id
;
5071 Rhs_Discr_Val
: Node_Id
;
5074 -- Per-object constrained selected components require special
5075 -- attention. If the enclosing scope of the component is an
5076 -- Unchecked_Union, we cannot reference its discriminants
5077 -- directly. This is why we use the two extra parameters of
5078 -- the equality function of the enclosing Unchecked_Union.
5080 -- type UU_Type (Discr : Integer := 0) is
5083 -- pragma Unchecked_Union (UU_Type);
5085 -- 1. Unchecked_Union enclosing record:
5087 -- type Enclosing_UU_Type (Discr : Integer := 0) is record
5089 -- Comp : UU_Type (Discr);
5091 -- end Enclosing_UU_Type;
5092 -- pragma Unchecked_Union (Enclosing_UU_Type);
5094 -- Obj1 : Enclosing_UU_Type;
5095 -- Obj2 : Enclosing_UU_Type (1);
5097 -- [. . .] Obj1 = Obj2 [. . .]
5101 -- if not (uu_typeEQ (obj1.comp, obj2.comp, a, b)) then
5103 -- A and B are the formal parameters of the equality function
5104 -- of Enclosing_UU_Type. The function always has two extra
5105 -- formals to capture the inferred discriminant values.
5107 -- 2. Non-Unchecked_Union enclosing record:
5110 -- Enclosing_Non_UU_Type (Discr : Integer := 0)
5113 -- Comp : UU_Type (Discr);
5115 -- end Enclosing_Non_UU_Type;
5117 -- Obj1 : Enclosing_Non_UU_Type;
5118 -- Obj2 : Enclosing_Non_UU_Type (1);
5120 -- ... Obj1 = Obj2 ...
5124 -- if not (uu_typeEQ (obj1.comp, obj2.comp,
5125 -- obj1.discr, obj2.discr)) then
5127 -- In this case we can directly reference the discriminants of
5128 -- the enclosing record.
5132 if Nkind
(Lhs
) = N_Selected_Component
5133 and then Has_Per_Object_Constraint
5134 (Entity
(Selector_Name
(Lhs
)))
5136 -- Enclosing record is an Unchecked_Union, use formal A
5138 if Is_Unchecked_Union
(Scope
5139 (Entity
(Selector_Name
(Lhs
))))
5142 Make_Identifier
(Loc
,
5145 -- Enclosing record is of a non-Unchecked_Union type, it is
5146 -- possible to reference the discriminant.
5150 Make_Selected_Component
(Loc
,
5151 Prefix
=> Prefix
(Lhs
),
5154 (Get_Discriminant_Value
5155 (First_Discriminant
(Lhs_Type
),
5157 Stored_Constraint
(Lhs_Type
))));
5160 -- Comment needed here ???
5163 -- Infer the discriminant value
5167 (Get_Discriminant_Value
5168 (First_Discriminant
(Lhs_Type
),
5170 Stored_Constraint
(Lhs_Type
)));
5175 if Nkind
(Rhs
) = N_Selected_Component
5176 and then Has_Per_Object_Constraint
5177 (Entity
(Selector_Name
(Rhs
)))
5179 if Is_Unchecked_Union
5180 (Scope
(Entity
(Selector_Name
(Rhs
))))
5183 Make_Identifier
(Loc
,
5188 Make_Selected_Component
(Loc
,
5189 Prefix
=> Prefix
(Rhs
),
5191 New_Copy
(Get_Discriminant_Value
(
5192 First_Discriminant
(Rhs_Type
),
5194 Stored_Constraint
(Rhs_Type
))));
5199 New_Copy
(Get_Discriminant_Value
(
5200 First_Discriminant
(Rhs_Type
),
5202 Stored_Constraint
(Rhs_Type
)));
5207 Make_Function_Call
(Loc
,
5208 Name
=> New_Reference_To
(Eq
, Loc
),
5209 Parameter_Associations
=> New_List
(
5216 -- Normal case, not an unchecked union
5220 Make_Function_Call
(Loc
,
5221 Name
=> New_Reference_To
(Eq
, Loc
),
5222 Parameter_Associations
=> New_List
(L_Exp
, R_Exp
)));
5225 Analyze_And_Resolve
(N
, Standard_Boolean
, Suppress
=> All_Checks
);
5226 end Build_Equality_Call
;
5228 ------------------------------------
5229 -- Has_Unconstrained_UU_Component --
5230 ------------------------------------
5232 function Has_Unconstrained_UU_Component
5233 (Typ
: Node_Id
) return Boolean
5235 Tdef
: constant Node_Id
:=
5236 Type_Definition
(Declaration_Node
(Base_Type
(Typ
)));
5240 function Component_Is_Unconstrained_UU
5241 (Comp
: Node_Id
) return Boolean;
5242 -- Determines whether the subtype of the component is an
5243 -- unconstrained Unchecked_Union.
5245 function Variant_Is_Unconstrained_UU
5246 (Variant
: Node_Id
) return Boolean;
5247 -- Determines whether a component of the variant has an unconstrained
5248 -- Unchecked_Union subtype.
5250 -----------------------------------
5251 -- Component_Is_Unconstrained_UU --
5252 -----------------------------------
5254 function Component_Is_Unconstrained_UU
5255 (Comp
: Node_Id
) return Boolean
5258 if Nkind
(Comp
) /= N_Component_Declaration
then
5263 Sindic
: constant Node_Id
:=
5264 Subtype_Indication
(Component_Definition
(Comp
));
5267 -- Unconstrained nominal type. In the case of a constraint
5268 -- present, the node kind would have been N_Subtype_Indication.
5270 if Nkind
(Sindic
) = N_Identifier
then
5271 return Is_Unchecked_Union
(Base_Type
(Etype
(Sindic
)));
5276 end Component_Is_Unconstrained_UU
;
5278 ---------------------------------
5279 -- Variant_Is_Unconstrained_UU --
5280 ---------------------------------
5282 function Variant_Is_Unconstrained_UU
5283 (Variant
: Node_Id
) return Boolean
5285 Clist
: constant Node_Id
:= Component_List
(Variant
);
5288 if Is_Empty_List
(Component_Items
(Clist
)) then
5292 -- We only need to test one component
5295 Comp
: Node_Id
:= First
(Component_Items
(Clist
));
5298 while Present
(Comp
) loop
5299 if Component_Is_Unconstrained_UU
(Comp
) then
5307 -- None of the components withing the variant were of
5308 -- unconstrained Unchecked_Union type.
5311 end Variant_Is_Unconstrained_UU
;
5313 -- Start of processing for Has_Unconstrained_UU_Component
5316 if Null_Present
(Tdef
) then
5320 Clist
:= Component_List
(Tdef
);
5321 Vpart
:= Variant_Part
(Clist
);
5323 -- Inspect available components
5325 if Present
(Component_Items
(Clist
)) then
5327 Comp
: Node_Id
:= First
(Component_Items
(Clist
));
5330 while Present
(Comp
) loop
5332 -- One component is sufficient
5334 if Component_Is_Unconstrained_UU
(Comp
) then
5343 -- Inspect available components withing variants
5345 if Present
(Vpart
) then
5347 Variant
: Node_Id
:= First
(Variants
(Vpart
));
5350 while Present
(Variant
) loop
5352 -- One component within a variant is sufficient
5354 if Variant_Is_Unconstrained_UU
(Variant
) then
5363 -- Neither the available components, nor the components inside the
5364 -- variant parts were of an unconstrained Unchecked_Union subtype.
5367 end Has_Unconstrained_UU_Component
;
5369 -- Start of processing for Expand_N_Op_Eq
5372 Binary_Op_Validity_Checks
(N
);
5374 if Ekind
(Typl
) = E_Private_Type
then
5375 Typl
:= Underlying_Type
(Typl
);
5376 elsif Ekind
(Typl
) = E_Private_Subtype
then
5377 Typl
:= Underlying_Type
(Base_Type
(Typl
));
5382 -- It may happen in error situations that the underlying type is not
5383 -- set. The error will be detected later, here we just defend the
5390 Typl
:= Base_Type
(Typl
);
5392 -- Boolean types (requiring handling of non-standard case)
5394 if Is_Boolean_Type
(Typl
) then
5395 Adjust_Condition
(Left_Opnd
(N
));
5396 Adjust_Condition
(Right_Opnd
(N
));
5397 Set_Etype
(N
, Standard_Boolean
);
5398 Adjust_Result_Type
(N
, Typ
);
5402 elsif Is_Array_Type
(Typl
) then
5404 -- If we are doing full validity checking, and it is possible for the
5405 -- array elements to be invalid then expand out array comparisons to
5406 -- make sure that we check the array elements.
5408 if Validity_Check_Operands
5409 and then not Is_Known_Valid
(Component_Type
(Typl
))
5412 Save_Force_Validity_Checks
: constant Boolean :=
5413 Force_Validity_Checks
;
5415 Force_Validity_Checks
:= True;
5417 Expand_Array_Equality
5419 Relocate_Node
(Lhs
),
5420 Relocate_Node
(Rhs
),
5423 Insert_Actions
(N
, Bodies
);
5424 Analyze_And_Resolve
(N
, Standard_Boolean
);
5425 Force_Validity_Checks
:= Save_Force_Validity_Checks
;
5428 -- Packed case where both operands are known aligned
5430 elsif Is_Bit_Packed_Array
(Typl
)
5431 and then not Is_Possibly_Unaligned_Object
(Lhs
)
5432 and then not Is_Possibly_Unaligned_Object
(Rhs
)
5434 Expand_Packed_Eq
(N
);
5436 -- Where the component type is elementary we can use a block bit
5437 -- comparison (if supported on the target) exception in the case
5438 -- of floating-point (negative zero issues require element by
5439 -- element comparison), and atomic types (where we must be sure
5440 -- to load elements independently) and possibly unaligned arrays.
5442 elsif Is_Elementary_Type
(Component_Type
(Typl
))
5443 and then not Is_Floating_Point_Type
(Component_Type
(Typl
))
5444 and then not Is_Atomic
(Component_Type
(Typl
))
5445 and then not Is_Possibly_Unaligned_Object
(Lhs
)
5446 and then not Is_Possibly_Unaligned_Object
(Rhs
)
5447 and then Support_Composite_Compare_On_Target
5451 -- For composite and floating-point cases, expand equality loop to
5452 -- make sure of using proper comparisons for tagged types, and
5453 -- correctly handling the floating-point case.
5457 Expand_Array_Equality
5459 Relocate_Node
(Lhs
),
5460 Relocate_Node
(Rhs
),
5463 Insert_Actions
(N
, Bodies
, Suppress
=> All_Checks
);
5464 Analyze_And_Resolve
(N
, Standard_Boolean
, Suppress
=> All_Checks
);
5469 elsif Is_Record_Type
(Typl
) then
5471 -- For tagged types, use the primitive "="
5473 if Is_Tagged_Type
(Typl
) then
5475 -- No need to do anything else compiling under restriction
5476 -- No_Dispatching_Calls. During the semantic analysis we
5477 -- already notified such violation.
5479 if Restriction_Active
(No_Dispatching_Calls
) then
5483 -- If this is derived from an untagged private type completed with
5484 -- a tagged type, it does not have a full view, so we use the
5485 -- primitive operations of the private type. This check should no
5486 -- longer be necessary when these types get their full views???
5488 if Is_Private_Type
(A_Typ
)
5489 and then not Is_Tagged_Type
(A_Typ
)
5490 and then Is_Derived_Type
(A_Typ
)
5491 and then No
(Full_View
(A_Typ
))
5493 -- Search for equality operation, checking that the operands
5494 -- have the same type. Note that we must find a matching entry,
5495 -- or something is very wrong!
5497 Prim
:= First_Elmt
(Collect_Primitive_Operations
(A_Typ
));
5499 while Present
(Prim
) loop
5500 exit when Chars
(Node
(Prim
)) = Name_Op_Eq
5501 and then Etype
(First_Formal
(Node
(Prim
))) =
5502 Etype
(Next_Formal
(First_Formal
(Node
(Prim
))))
5504 Base_Type
(Etype
(Node
(Prim
))) = Standard_Boolean
;
5509 pragma Assert
(Present
(Prim
));
5510 Op_Name
:= Node
(Prim
);
5512 -- Find the type's predefined equality or an overriding
5513 -- user- defined equality. The reason for not simply calling
5514 -- Find_Prim_Op here is that there may be a user-defined
5515 -- overloaded equality op that precedes the equality that we want,
5516 -- so we have to explicitly search (e.g., there could be an
5517 -- equality with two different parameter types).
5520 if Is_Class_Wide_Type
(Typl
) then
5521 Typl
:= Root_Type
(Typl
);
5524 Prim
:= First_Elmt
(Primitive_Operations
(Typl
));
5525 while Present
(Prim
) loop
5526 exit when Chars
(Node
(Prim
)) = Name_Op_Eq
5527 and then Etype
(First_Formal
(Node
(Prim
))) =
5528 Etype
(Next_Formal
(First_Formal
(Node
(Prim
))))
5530 Base_Type
(Etype
(Node
(Prim
))) = Standard_Boolean
;
5535 pragma Assert
(Present
(Prim
));
5536 Op_Name
:= Node
(Prim
);
5539 Build_Equality_Call
(Op_Name
);
5541 -- Ada 2005 (AI-216): Program_Error is raised when evaluating the
5542 -- predefined equality operator for a type which has a subcomponent
5543 -- of an Unchecked_Union type whose nominal subtype is unconstrained.
5545 elsif Has_Unconstrained_UU_Component
(Typl
) then
5547 Make_Raise_Program_Error
(Loc
,
5548 Reason
=> PE_Unchecked_Union_Restriction
));
5550 -- Prevent Gigi from generating incorrect code by rewriting the
5551 -- equality as a standard False.
5554 New_Occurrence_Of
(Standard_False
, Loc
));
5556 elsif Is_Unchecked_Union
(Typl
) then
5558 -- If we can infer the discriminants of the operands, we make a
5559 -- call to the TSS equality function.
5561 if Has_Inferable_Discriminants
(Lhs
)
5563 Has_Inferable_Discriminants
(Rhs
)
5566 (TSS
(Root_Type
(Typl
), TSS_Composite_Equality
));
5569 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
5570 -- the predefined equality operator for an Unchecked_Union type
5571 -- if either of the operands lack inferable discriminants.
5574 Make_Raise_Program_Error
(Loc
,
5575 Reason
=> PE_Unchecked_Union_Restriction
));
5577 -- Prevent Gigi from generating incorrect code by rewriting
5578 -- the equality as a standard False.
5581 New_Occurrence_Of
(Standard_False
, Loc
));
5585 -- If a type support function is present (for complex cases), use it
5587 elsif Present
(TSS
(Root_Type
(Typl
), TSS_Composite_Equality
)) then
5589 (TSS
(Root_Type
(Typl
), TSS_Composite_Equality
));
5591 -- Otherwise expand the component by component equality. Note that
5592 -- we never use block-bit comparisons for records, because of the
5593 -- problems with gaps. The backend will often be able to recombine
5594 -- the separate comparisons that we generate here.
5597 Remove_Side_Effects
(Lhs
);
5598 Remove_Side_Effects
(Rhs
);
5600 Expand_Record_Equality
(N
, Typl
, Lhs
, Rhs
, Bodies
));
5602 Insert_Actions
(N
, Bodies
, Suppress
=> All_Checks
);
5603 Analyze_And_Resolve
(N
, Standard_Boolean
, Suppress
=> All_Checks
);
5607 -- Test if result is known at compile time
5609 Rewrite_Comparison
(N
);
5611 -- If we still have comparison for Vax_Float, process it
5613 if Vax_Float
(Typl
) and then Nkind
(N
) in N_Op_Compare
then
5614 Expand_Vax_Comparison
(N
);
5619 -----------------------
5620 -- Expand_N_Op_Expon --
5621 -----------------------
5623 procedure Expand_N_Op_Expon
(N
: Node_Id
) is
5624 Loc
: constant Source_Ptr
:= Sloc
(N
);
5625 Typ
: constant Entity_Id
:= Etype
(N
);
5626 Rtyp
: constant Entity_Id
:= Root_Type
(Typ
);
5627 Base
: constant Node_Id
:= Relocate_Node
(Left_Opnd
(N
));
5628 Bastyp
: constant Node_Id
:= Etype
(Base
);
5629 Exp
: constant Node_Id
:= Relocate_Node
(Right_Opnd
(N
));
5630 Exptyp
: constant Entity_Id
:= Etype
(Exp
);
5631 Ovflo
: constant Boolean := Do_Overflow_Check
(N
);
5640 Binary_Op_Validity_Checks
(N
);
5642 -- If either operand is of a private type, then we have the use of an
5643 -- intrinsic operator, and we get rid of the privateness, by using root
5644 -- types of underlying types for the actual operation. Otherwise the
5645 -- private types will cause trouble if we expand multiplications or
5646 -- shifts etc. We also do this transformation if the result type is
5647 -- different from the base type.
5649 if Is_Private_Type
(Etype
(Base
))
5651 Is_Private_Type
(Typ
)
5653 Is_Private_Type
(Exptyp
)
5655 Rtyp
/= Root_Type
(Bastyp
)
5658 Bt
: constant Entity_Id
:= Root_Type
(Underlying_Type
(Bastyp
));
5659 Et
: constant Entity_Id
:= Root_Type
(Underlying_Type
(Exptyp
));
5663 Unchecked_Convert_To
(Typ
,
5665 Left_Opnd
=> Unchecked_Convert_To
(Bt
, Base
),
5666 Right_Opnd
=> Unchecked_Convert_To
(Et
, Exp
))));
5667 Analyze_And_Resolve
(N
, Typ
);
5672 -- Test for case of known right argument
5674 if Compile_Time_Known_Value
(Exp
) then
5675 Expv
:= Expr_Value
(Exp
);
5677 -- We only fold small non-negative exponents. You might think we
5678 -- could fold small negative exponents for the real case, but we
5679 -- can't because we are required to raise Constraint_Error for
5680 -- the case of 0.0 ** (negative) even if Machine_Overflows = False.
5681 -- See ACVC test C4A012B.
5683 if Expv
>= 0 and then Expv
<= 4 then
5685 -- X ** 0 = 1 (or 1.0)
5689 -- Call Remove_Side_Effects to ensure that any side effects
5690 -- in the ignored left operand (in particular function calls
5691 -- to user defined functions) are properly executed.
5693 Remove_Side_Effects
(Base
);
5695 if Ekind
(Typ
) in Integer_Kind
then
5696 Xnode
:= Make_Integer_Literal
(Loc
, Intval
=> 1);
5698 Xnode
:= Make_Real_Literal
(Loc
, Ureal_1
);
5710 Make_Op_Multiply
(Loc
,
5711 Left_Opnd
=> Duplicate_Subexpr
(Base
),
5712 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Base
));
5714 -- X ** 3 = X * X * X
5718 Make_Op_Multiply
(Loc
,
5720 Make_Op_Multiply
(Loc
,
5721 Left_Opnd
=> Duplicate_Subexpr
(Base
),
5722 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Base
)),
5723 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Base
));
5726 -- En : constant base'type := base * base;
5732 Make_Defining_Identifier
(Loc
, New_Internal_Name
('E'));
5734 Insert_Actions
(N
, New_List
(
5735 Make_Object_Declaration
(Loc
,
5736 Defining_Identifier
=> Temp
,
5737 Constant_Present
=> True,
5738 Object_Definition
=> New_Reference_To
(Typ
, Loc
),
5740 Make_Op_Multiply
(Loc
,
5741 Left_Opnd
=> Duplicate_Subexpr
(Base
),
5742 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Base
)))));
5745 Make_Op_Multiply
(Loc
,
5746 Left_Opnd
=> New_Reference_To
(Temp
, Loc
),
5747 Right_Opnd
=> New_Reference_To
(Temp
, Loc
));
5751 Analyze_And_Resolve
(N
, Typ
);
5756 -- Case of (2 ** expression) appearing as an argument of an integer
5757 -- multiplication, or as the right argument of a division of a non-
5758 -- negative integer. In such cases we leave the node untouched, setting
5759 -- the flag Is_Natural_Power_Of_2_for_Shift set, then the expansion
5760 -- of the higher level node converts it into a shift.
5762 -- Note: this transformation is not applicable for a modular type with
5763 -- a non-binary modulus in the multiplication case, since we get a wrong
5764 -- result if the shift causes an overflow before the modular reduction.
5766 if Nkind
(Base
) = N_Integer_Literal
5767 and then Intval
(Base
) = 2
5768 and then Is_Integer_Type
(Root_Type
(Exptyp
))
5769 and then Esize
(Root_Type
(Exptyp
)) <= Esize
(Standard_Integer
)
5770 and then Is_Unsigned_Type
(Exptyp
)
5772 and then Nkind
(Parent
(N
)) in N_Binary_Op
5775 P
: constant Node_Id
:= Parent
(N
);
5776 L
: constant Node_Id
:= Left_Opnd
(P
);
5777 R
: constant Node_Id
:= Right_Opnd
(P
);
5780 if (Nkind
(P
) = N_Op_Multiply
5781 and then not Non_Binary_Modulus
(Typ
)
5783 ((Is_Integer_Type
(Etype
(L
)) and then R
= N
)
5785 (Is_Integer_Type
(Etype
(R
)) and then L
= N
))
5786 and then not Do_Overflow_Check
(P
))
5789 (Nkind
(P
) = N_Op_Divide
5790 and then Is_Integer_Type
(Etype
(L
))
5791 and then Is_Unsigned_Type
(Etype
(L
))
5793 and then not Do_Overflow_Check
(P
))
5795 Set_Is_Power_Of_2_For_Shift
(N
);
5801 -- Fall through if exponentiation must be done using a runtime routine
5803 -- First deal with modular case
5805 if Is_Modular_Integer_Type
(Rtyp
) then
5807 -- Non-binary case, we call the special exponentiation routine for
5808 -- the non-binary case, converting the argument to Long_Long_Integer
5809 -- and passing the modulus value. Then the result is converted back
5810 -- to the base type.
5812 if Non_Binary_Modulus
(Rtyp
) then
5815 Make_Function_Call
(Loc
,
5816 Name
=> New_Reference_To
(RTE
(RE_Exp_Modular
), Loc
),
5817 Parameter_Associations
=> New_List
(
5818 Convert_To
(Standard_Integer
, Base
),
5819 Make_Integer_Literal
(Loc
, Modulus
(Rtyp
)),
5822 -- Binary case, in this case, we call one of two routines, either the
5823 -- unsigned integer case, or the unsigned long long integer case,
5824 -- with a final "and" operation to do the required mod.
5827 if UI_To_Int
(Esize
(Rtyp
)) <= Standard_Integer_Size
then
5828 Ent
:= RTE
(RE_Exp_Unsigned
);
5830 Ent
:= RTE
(RE_Exp_Long_Long_Unsigned
);
5837 Make_Function_Call
(Loc
,
5838 Name
=> New_Reference_To
(Ent
, Loc
),
5839 Parameter_Associations
=> New_List
(
5840 Convert_To
(Etype
(First_Formal
(Ent
)), Base
),
5843 Make_Integer_Literal
(Loc
, Modulus
(Rtyp
) - 1))));
5847 -- Common exit point for modular type case
5849 Analyze_And_Resolve
(N
, Typ
);
5852 -- Signed integer cases, done using either Integer or Long_Long_Integer.
5853 -- It is not worth having routines for Short_[Short_]Integer, since for
5854 -- most machines it would not help, and it would generate more code that
5855 -- might need certification when a certified run time is required.
5857 -- In the integer cases, we have two routines, one for when overflow
5858 -- checks are required, and one when they are not required, since there
5859 -- is a real gain in omitting checks on many machines.
5861 elsif Rtyp
= Base_Type
(Standard_Long_Long_Integer
)
5862 or else (Rtyp
= Base_Type
(Standard_Long_Integer
)
5864 Esize
(Standard_Long_Integer
) > Esize
(Standard_Integer
))
5865 or else (Rtyp
= Universal_Integer
)
5867 Etyp
:= Standard_Long_Long_Integer
;
5870 Rent
:= RE_Exp_Long_Long_Integer
;
5872 Rent
:= RE_Exn_Long_Long_Integer
;
5875 elsif Is_Signed_Integer_Type
(Rtyp
) then
5876 Etyp
:= Standard_Integer
;
5879 Rent
:= RE_Exp_Integer
;
5881 Rent
:= RE_Exn_Integer
;
5884 -- Floating-point cases, always done using Long_Long_Float. We do not
5885 -- need separate routines for the overflow case here, since in the case
5886 -- of floating-point, we generate infinities anyway as a rule (either
5887 -- that or we automatically trap overflow), and if there is an infinity
5888 -- generated and a range check is required, the check will fail anyway.
5891 pragma Assert
(Is_Floating_Point_Type
(Rtyp
));
5892 Etyp
:= Standard_Long_Long_Float
;
5893 Rent
:= RE_Exn_Long_Long_Float
;
5896 -- Common processing for integer cases and floating-point cases.
5897 -- If we are in the right type, we can call runtime routine directly
5900 and then Rtyp
/= Universal_Integer
5901 and then Rtyp
/= Universal_Real
5904 Make_Function_Call
(Loc
,
5905 Name
=> New_Reference_To
(RTE
(Rent
), Loc
),
5906 Parameter_Associations
=> New_List
(Base
, Exp
)));
5908 -- Otherwise we have to introduce conversions (conversions are also
5909 -- required in the universal cases, since the runtime routine is
5910 -- typed using one of the standard types).
5915 Make_Function_Call
(Loc
,
5916 Name
=> New_Reference_To
(RTE
(Rent
), Loc
),
5917 Parameter_Associations
=> New_List
(
5918 Convert_To
(Etyp
, Base
),
5922 Analyze_And_Resolve
(N
, Typ
);
5926 when RE_Not_Available
=>
5928 end Expand_N_Op_Expon
;
5930 --------------------
5931 -- Expand_N_Op_Ge --
5932 --------------------
5934 procedure Expand_N_Op_Ge
(N
: Node_Id
) is
5935 Typ
: constant Entity_Id
:= Etype
(N
);
5936 Op1
: constant Node_Id
:= Left_Opnd
(N
);
5937 Op2
: constant Node_Id
:= Right_Opnd
(N
);
5938 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
5941 Binary_Op_Validity_Checks
(N
);
5943 if Is_Array_Type
(Typ1
) then
5944 Expand_Array_Comparison
(N
);
5948 if Is_Boolean_Type
(Typ1
) then
5949 Adjust_Condition
(Op1
);
5950 Adjust_Condition
(Op2
);
5951 Set_Etype
(N
, Standard_Boolean
);
5952 Adjust_Result_Type
(N
, Typ
);
5955 Rewrite_Comparison
(N
);
5957 -- If we still have comparison, and Vax_Float type, process it
5959 if Vax_Float
(Typ1
) and then Nkind
(N
) in N_Op_Compare
then
5960 Expand_Vax_Comparison
(N
);
5965 --------------------
5966 -- Expand_N_Op_Gt --
5967 --------------------
5969 procedure Expand_N_Op_Gt
(N
: Node_Id
) is
5970 Typ
: constant Entity_Id
:= Etype
(N
);
5971 Op1
: constant Node_Id
:= Left_Opnd
(N
);
5972 Op2
: constant Node_Id
:= Right_Opnd
(N
);
5973 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
5976 Binary_Op_Validity_Checks
(N
);
5978 if Is_Array_Type
(Typ1
) then
5979 Expand_Array_Comparison
(N
);
5983 if Is_Boolean_Type
(Typ1
) then
5984 Adjust_Condition
(Op1
);
5985 Adjust_Condition
(Op2
);
5986 Set_Etype
(N
, Standard_Boolean
);
5987 Adjust_Result_Type
(N
, Typ
);
5990 Rewrite_Comparison
(N
);
5992 -- If we still have comparison, and Vax_Float type, process it
5994 if Vax_Float
(Typ1
) and then Nkind
(N
) in N_Op_Compare
then
5995 Expand_Vax_Comparison
(N
);
6000 --------------------
6001 -- Expand_N_Op_Le --
6002 --------------------
6004 procedure Expand_N_Op_Le
(N
: Node_Id
) is
6005 Typ
: constant Entity_Id
:= Etype
(N
);
6006 Op1
: constant Node_Id
:= Left_Opnd
(N
);
6007 Op2
: constant Node_Id
:= Right_Opnd
(N
);
6008 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
6011 Binary_Op_Validity_Checks
(N
);
6013 if Is_Array_Type
(Typ1
) then
6014 Expand_Array_Comparison
(N
);
6018 if Is_Boolean_Type
(Typ1
) then
6019 Adjust_Condition
(Op1
);
6020 Adjust_Condition
(Op2
);
6021 Set_Etype
(N
, Standard_Boolean
);
6022 Adjust_Result_Type
(N
, Typ
);
6025 Rewrite_Comparison
(N
);
6027 -- If we still have comparison, and Vax_Float type, process it
6029 if Vax_Float
(Typ1
) and then Nkind
(N
) in N_Op_Compare
then
6030 Expand_Vax_Comparison
(N
);
6035 --------------------
6036 -- Expand_N_Op_Lt --
6037 --------------------
6039 procedure Expand_N_Op_Lt
(N
: Node_Id
) is
6040 Typ
: constant Entity_Id
:= Etype
(N
);
6041 Op1
: constant Node_Id
:= Left_Opnd
(N
);
6042 Op2
: constant Node_Id
:= Right_Opnd
(N
);
6043 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
6046 Binary_Op_Validity_Checks
(N
);
6048 if Is_Array_Type
(Typ1
) then
6049 Expand_Array_Comparison
(N
);
6053 if Is_Boolean_Type
(Typ1
) then
6054 Adjust_Condition
(Op1
);
6055 Adjust_Condition
(Op2
);
6056 Set_Etype
(N
, Standard_Boolean
);
6057 Adjust_Result_Type
(N
, Typ
);
6060 Rewrite_Comparison
(N
);
6062 -- If we still have comparison, and Vax_Float type, process it
6064 if Vax_Float
(Typ1
) and then Nkind
(N
) in N_Op_Compare
then
6065 Expand_Vax_Comparison
(N
);
6070 -----------------------
6071 -- Expand_N_Op_Minus --
6072 -----------------------
6074 procedure Expand_N_Op_Minus
(N
: Node_Id
) is
6075 Loc
: constant Source_Ptr
:= Sloc
(N
);
6076 Typ
: constant Entity_Id
:= Etype
(N
);
6079 Unary_Op_Validity_Checks
(N
);
6081 if not Backend_Overflow_Checks_On_Target
6082 and then Is_Signed_Integer_Type
(Etype
(N
))
6083 and then Do_Overflow_Check
(N
)
6085 -- Software overflow checking expands -expr into (0 - expr)
6088 Make_Op_Subtract
(Loc
,
6089 Left_Opnd
=> Make_Integer_Literal
(Loc
, 0),
6090 Right_Opnd
=> Right_Opnd
(N
)));
6092 Analyze_And_Resolve
(N
, Typ
);
6094 -- Vax floating-point types case
6096 elsif Vax_Float
(Etype
(N
)) then
6097 Expand_Vax_Arith
(N
);
6099 end Expand_N_Op_Minus
;
6101 ---------------------
6102 -- Expand_N_Op_Mod --
6103 ---------------------
6105 procedure Expand_N_Op_Mod
(N
: Node_Id
) is
6106 Loc
: constant Source_Ptr
:= Sloc
(N
);
6107 Typ
: constant Entity_Id
:= Etype
(N
);
6108 Left
: constant Node_Id
:= Left_Opnd
(N
);
6109 Right
: constant Node_Id
:= Right_Opnd
(N
);
6110 DOC
: constant Boolean := Do_Overflow_Check
(N
);
6111 DDC
: constant Boolean := Do_Division_Check
(N
);
6121 pragma Warnings
(Off
, Lhi
);
6124 Binary_Op_Validity_Checks
(N
);
6126 Determine_Range
(Right
, ROK
, Rlo
, Rhi
);
6127 Determine_Range
(Left
, LOK
, Llo
, Lhi
);
6129 -- Convert mod to rem if operands are known non-negative. We do this
6130 -- since it is quite likely that this will improve the quality of code,
6131 -- (the operation now corresponds to the hardware remainder), and it
6132 -- does not seem likely that it could be harmful.
6134 if LOK
and then Llo
>= 0
6136 ROK
and then Rlo
>= 0
6139 Make_Op_Rem
(Sloc
(N
),
6140 Left_Opnd
=> Left_Opnd
(N
),
6141 Right_Opnd
=> Right_Opnd
(N
)));
6143 -- Instead of reanalyzing the node we do the analysis manually. This
6144 -- avoids anomalies when the replacement is done in an instance and
6145 -- is epsilon more efficient.
6147 Set_Entity
(N
, Standard_Entity
(S_Op_Rem
));
6149 Set_Do_Overflow_Check
(N
, DOC
);
6150 Set_Do_Division_Check
(N
, DDC
);
6151 Expand_N_Op_Rem
(N
);
6154 -- Otherwise, normal mod processing
6157 if Is_Integer_Type
(Etype
(N
)) then
6158 Apply_Divide_Check
(N
);
6161 -- Apply optimization x mod 1 = 0. We don't really need that with
6162 -- gcc, but it is useful with other back ends (e.g. AAMP), and is
6163 -- certainly harmless.
6165 if Is_Integer_Type
(Etype
(N
))
6166 and then Compile_Time_Known_Value
(Right
)
6167 and then Expr_Value
(Right
) = Uint_1
6169 -- Call Remove_Side_Effects to ensure that any side effects in
6170 -- the ignored left operand (in particular function calls to
6171 -- user defined functions) are properly executed.
6173 Remove_Side_Effects
(Left
);
6175 Rewrite
(N
, Make_Integer_Literal
(Loc
, 0));
6176 Analyze_And_Resolve
(N
, Typ
);
6180 -- Deal with annoying case of largest negative number remainder
6181 -- minus one. Gigi does not handle this case correctly, because
6182 -- it generates a divide instruction which may trap in this case.
6184 -- In fact the check is quite easy, if the right operand is -1, then
6185 -- the mod value is always 0, and we can just ignore the left operand
6186 -- completely in this case.
6188 -- The operand type may be private (e.g. in the expansion of an
6189 -- intrinsic operation) so we must use the underlying type to get the
6190 -- bounds, and convert the literals explicitly.
6194 (Type_Low_Bound
(Base_Type
(Underlying_Type
(Etype
(Left
)))));
6196 if ((not ROK
) or else (Rlo
<= (-1) and then (-1) <= Rhi
))
6198 ((not LOK
) or else (Llo
= LLB
))
6201 Make_Conditional_Expression
(Loc
,
6202 Expressions
=> New_List
(
6204 Left_Opnd
=> Duplicate_Subexpr
(Right
),
6206 Unchecked_Convert_To
(Typ
,
6207 Make_Integer_Literal
(Loc
, -1))),
6208 Unchecked_Convert_To
(Typ
,
6209 Make_Integer_Literal
(Loc
, Uint_0
)),
6210 Relocate_Node
(N
))));
6212 Set_Analyzed
(Next
(Next
(First
(Expressions
(N
)))));
6213 Analyze_And_Resolve
(N
, Typ
);
6216 end Expand_N_Op_Mod
;
6218 --------------------------
6219 -- Expand_N_Op_Multiply --
6220 --------------------------
6222 procedure Expand_N_Op_Multiply
(N
: Node_Id
) is
6223 Loc
: constant Source_Ptr
:= Sloc
(N
);
6224 Lop
: constant Node_Id
:= Left_Opnd
(N
);
6225 Rop
: constant Node_Id
:= Right_Opnd
(N
);
6227 Lp2
: constant Boolean :=
6228 Nkind
(Lop
) = N_Op_Expon
6229 and then Is_Power_Of_2_For_Shift
(Lop
);
6231 Rp2
: constant Boolean :=
6232 Nkind
(Rop
) = N_Op_Expon
6233 and then Is_Power_Of_2_For_Shift
(Rop
);
6235 Ltyp
: constant Entity_Id
:= Etype
(Lop
);
6236 Rtyp
: constant Entity_Id
:= Etype
(Rop
);
6237 Typ
: Entity_Id
:= Etype
(N
);
6240 Binary_Op_Validity_Checks
(N
);
6242 -- Special optimizations for integer types
6244 if Is_Integer_Type
(Typ
) then
6246 -- N * 0 = 0 for integer types
6248 if Compile_Time_Known_Value
(Rop
)
6249 and then Expr_Value
(Rop
) = Uint_0
6251 -- Call Remove_Side_Effects to ensure that any side effects in
6252 -- the ignored left operand (in particular function calls to
6253 -- user defined functions) are properly executed.
6255 Remove_Side_Effects
(Lop
);
6257 Rewrite
(N
, Make_Integer_Literal
(Loc
, Uint_0
));
6258 Analyze_And_Resolve
(N
, Typ
);
6262 -- Similar handling for 0 * N = 0
6264 if Compile_Time_Known_Value
(Lop
)
6265 and then Expr_Value
(Lop
) = Uint_0
6267 Remove_Side_Effects
(Rop
);
6268 Rewrite
(N
, Make_Integer_Literal
(Loc
, Uint_0
));
6269 Analyze_And_Resolve
(N
, Typ
);
6273 -- N * 1 = 1 * N = N for integer types
6275 -- This optimisation is not done if we are going to
6276 -- rewrite the product 1 * 2 ** N to a shift.
6278 if Compile_Time_Known_Value
(Rop
)
6279 and then Expr_Value
(Rop
) = Uint_1
6285 elsif Compile_Time_Known_Value
(Lop
)
6286 and then Expr_Value
(Lop
) = Uint_1
6294 -- Convert x * 2 ** y to Shift_Left (x, y). Note that the fact that
6295 -- Is_Power_Of_2_For_Shift is set means that we know that our left
6296 -- operand is an integer, as required for this to work.
6301 -- Convert 2 ** A * 2 ** B into 2 ** (A + B)
6305 Left_Opnd
=> Make_Integer_Literal
(Loc
, 2),
6308 Left_Opnd
=> Right_Opnd
(Lop
),
6309 Right_Opnd
=> Right_Opnd
(Rop
))));
6310 Analyze_And_Resolve
(N
, Typ
);
6315 Make_Op_Shift_Left
(Loc
,
6318 Convert_To
(Standard_Natural
, Right_Opnd
(Rop
))));
6319 Analyze_And_Resolve
(N
, Typ
);
6323 -- Same processing for the operands the other way round
6327 Make_Op_Shift_Left
(Loc
,
6330 Convert_To
(Standard_Natural
, Right_Opnd
(Lop
))));
6331 Analyze_And_Resolve
(N
, Typ
);
6335 -- Do required fixup of universal fixed operation
6337 if Typ
= Universal_Fixed
then
6338 Fixup_Universal_Fixed_Operation
(N
);
6342 -- Multiplications with fixed-point results
6344 if Is_Fixed_Point_Type
(Typ
) then
6346 -- No special processing if Treat_Fixed_As_Integer is set, since from
6347 -- a semantic point of view such operations are simply integer
6348 -- operations and will be treated that way.
6350 if not Treat_Fixed_As_Integer
(N
) then
6352 -- Case of fixed * integer => fixed
6354 if Is_Integer_Type
(Rtyp
) then
6355 Expand_Multiply_Fixed_By_Integer_Giving_Fixed
(N
);
6357 -- Case of integer * fixed => fixed
6359 elsif Is_Integer_Type
(Ltyp
) then
6360 Expand_Multiply_Integer_By_Fixed_Giving_Fixed
(N
);
6362 -- Case of fixed * fixed => fixed
6365 Expand_Multiply_Fixed_By_Fixed_Giving_Fixed
(N
);
6369 -- Other cases of multiplication of fixed-point operands. Again we
6370 -- exclude the cases where Treat_Fixed_As_Integer flag is set.
6372 elsif (Is_Fixed_Point_Type
(Ltyp
) or else Is_Fixed_Point_Type
(Rtyp
))
6373 and then not Treat_Fixed_As_Integer
(N
)
6375 if Is_Integer_Type
(Typ
) then
6376 Expand_Multiply_Fixed_By_Fixed_Giving_Integer
(N
);
6378 pragma Assert
(Is_Floating_Point_Type
(Typ
));
6379 Expand_Multiply_Fixed_By_Fixed_Giving_Float
(N
);
6382 -- Mixed-mode operations can appear in a non-static universal context,
6383 -- in which case the integer argument must be converted explicitly.
6385 elsif Typ
= Universal_Real
6386 and then Is_Integer_Type
(Rtyp
)
6388 Rewrite
(Rop
, Convert_To
(Universal_Real
, Relocate_Node
(Rop
)));
6390 Analyze_And_Resolve
(Rop
, Universal_Real
);
6392 elsif Typ
= Universal_Real
6393 and then Is_Integer_Type
(Ltyp
)
6395 Rewrite
(Lop
, Convert_To
(Universal_Real
, Relocate_Node
(Lop
)));
6397 Analyze_And_Resolve
(Lop
, Universal_Real
);
6399 -- Non-fixed point cases, check software overflow checking required
6401 elsif Is_Signed_Integer_Type
(Etype
(N
)) then
6402 Apply_Arithmetic_Overflow_Check
(N
);
6404 -- Deal with VAX float case
6406 elsif Vax_Float
(Typ
) then
6407 Expand_Vax_Arith
(N
);
6410 end Expand_N_Op_Multiply
;
6412 --------------------
6413 -- Expand_N_Op_Ne --
6414 --------------------
6416 procedure Expand_N_Op_Ne
(N
: Node_Id
) is
6417 Typ
: constant Entity_Id
:= Etype
(Left_Opnd
(N
));
6420 -- Case of elementary type with standard operator
6422 if Is_Elementary_Type
(Typ
)
6423 and then Sloc
(Entity
(N
)) = Standard_Location
6425 Binary_Op_Validity_Checks
(N
);
6427 -- Boolean types (requiring handling of non-standard case)
6429 if Is_Boolean_Type
(Typ
) then
6430 Adjust_Condition
(Left_Opnd
(N
));
6431 Adjust_Condition
(Right_Opnd
(N
));
6432 Set_Etype
(N
, Standard_Boolean
);
6433 Adjust_Result_Type
(N
, Typ
);
6436 Rewrite_Comparison
(N
);
6438 -- If we still have comparison for Vax_Float, process it
6440 if Vax_Float
(Typ
) and then Nkind
(N
) in N_Op_Compare
then
6441 Expand_Vax_Comparison
(N
);
6445 -- For all cases other than elementary types, we rewrite node as the
6446 -- negation of an equality operation, and reanalyze. The equality to be
6447 -- used is defined in the same scope and has the same signature. This
6448 -- signature must be set explicitly since in an instance it may not have
6449 -- the same visibility as in the generic unit. This avoids duplicating
6450 -- or factoring the complex code for record/array equality tests etc.
6454 Loc
: constant Source_Ptr
:= Sloc
(N
);
6456 Ne
: constant Entity_Id
:= Entity
(N
);
6459 Binary_Op_Validity_Checks
(N
);
6465 Left_Opnd
=> Left_Opnd
(N
),
6466 Right_Opnd
=> Right_Opnd
(N
)));
6467 Set_Paren_Count
(Right_Opnd
(Neg
), 1);
6469 if Scope
(Ne
) /= Standard_Standard
then
6470 Set_Entity
(Right_Opnd
(Neg
), Corresponding_Equality
(Ne
));
6473 -- For navigation purposes, the inequality is treated as an
6474 -- implicit reference to the corresponding equality. Preserve the
6475 -- Comes_From_ source flag so that the proper Xref entry is
6478 Preserve_Comes_From_Source
(Neg
, N
);
6479 Preserve_Comes_From_Source
(Right_Opnd
(Neg
), N
);
6481 Analyze_And_Resolve
(N
, Standard_Boolean
);
6486 ---------------------
6487 -- Expand_N_Op_Not --
6488 ---------------------
6490 -- If the argument is other than a Boolean array type, there is no special
6491 -- expansion required.
6493 -- For the packed case, we call the special routine in Exp_Pakd, except
6494 -- that if the component size is greater than one, we use the standard
6495 -- routine generating a gruesome loop (it is so peculiar to have packed
6496 -- arrays with non-standard Boolean representations anyway, so it does not
6497 -- matter that we do not handle this case efficiently).
6499 -- For the unpacked case (and for the special packed case where we have non
6500 -- standard Booleans, as discussed above), we generate and insert into the
6501 -- tree the following function definition:
6503 -- function Nnnn (A : arr) is
6506 -- for J in a'range loop
6507 -- B (J) := not A (J);
6512 -- Here arr is the actual subtype of the parameter (and hence always
6513 -- constrained). Then we replace the not with a call to this function.
6515 procedure Expand_N_Op_Not
(N
: Node_Id
) is
6516 Loc
: constant Source_Ptr
:= Sloc
(N
);
6517 Typ
: constant Entity_Id
:= Etype
(N
);
6526 Func_Name
: Entity_Id
;
6527 Loop_Statement
: Node_Id
;
6530 Unary_Op_Validity_Checks
(N
);
6532 -- For boolean operand, deal with non-standard booleans
6534 if Is_Boolean_Type
(Typ
) then
6535 Adjust_Condition
(Right_Opnd
(N
));
6536 Set_Etype
(N
, Standard_Boolean
);
6537 Adjust_Result_Type
(N
, Typ
);
6541 -- Only array types need any other processing
6543 if not Is_Array_Type
(Typ
) then
6547 -- Case of array operand. If bit packed with a component size of 1,
6548 -- handle it in Exp_Pakd if the operand is known to be aligned.
6550 if Is_Bit_Packed_Array
(Typ
)
6551 and then Component_Size
(Typ
) = 1
6552 and then not Is_Possibly_Unaligned_Object
(Right_Opnd
(N
))
6554 Expand_Packed_Not
(N
);
6558 -- Case of array operand which is not bit-packed. If the context is
6559 -- a safe assignment, call in-place operation, If context is a larger
6560 -- boolean expression in the context of a safe assignment, expansion is
6561 -- done by enclosing operation.
6563 Opnd
:= Relocate_Node
(Right_Opnd
(N
));
6564 Convert_To_Actual_Subtype
(Opnd
);
6565 Arr
:= Etype
(Opnd
);
6566 Ensure_Defined
(Arr
, N
);
6567 Silly_Boolean_Array_Not_Test
(N
, Arr
);
6569 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
6570 if Safe_In_Place_Array_Op
(Name
(Parent
(N
)), N
, Empty
) then
6571 Build_Boolean_Array_Proc_Call
(Parent
(N
), Opnd
, Empty
);
6574 -- Special case the negation of a binary operation
6576 elsif Nkind_In
(Opnd
, N_Op_And
, N_Op_Or
, N_Op_Xor
)
6577 and then Safe_In_Place_Array_Op
6578 (Name
(Parent
(N
)), Left_Opnd
(Opnd
), Right_Opnd
(Opnd
))
6580 Build_Boolean_Array_Proc_Call
(Parent
(N
), Opnd
, Empty
);
6584 elsif Nkind
(Parent
(N
)) in N_Binary_Op
6585 and then Nkind
(Parent
(Parent
(N
))) = N_Assignment_Statement
6588 Op1
: constant Node_Id
:= Left_Opnd
(Parent
(N
));
6589 Op2
: constant Node_Id
:= Right_Opnd
(Parent
(N
));
6590 Lhs
: constant Node_Id
:= Name
(Parent
(Parent
(N
)));
6593 if Safe_In_Place_Array_Op
(Lhs
, Op1
, Op2
) then
6595 and then Nkind
(Op2
) = N_Op_Not
6597 -- (not A) op (not B) can be reduced to a single call
6602 and then Nkind
(Parent
(N
)) = N_Op_Xor
6604 -- A xor (not B) can also be special-cased
6612 A
:= Make_Defining_Identifier
(Loc
, Name_uA
);
6613 B
:= Make_Defining_Identifier
(Loc
, Name_uB
);
6614 J
:= Make_Defining_Identifier
(Loc
, Name_uJ
);
6617 Make_Indexed_Component
(Loc
,
6618 Prefix
=> New_Reference_To
(A
, Loc
),
6619 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)));
6622 Make_Indexed_Component
(Loc
,
6623 Prefix
=> New_Reference_To
(B
, Loc
),
6624 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)));
6627 Make_Implicit_Loop_Statement
(N
,
6628 Identifier
=> Empty
,
6631 Make_Iteration_Scheme
(Loc
,
6632 Loop_Parameter_Specification
=>
6633 Make_Loop_Parameter_Specification
(Loc
,
6634 Defining_Identifier
=> J
,
6635 Discrete_Subtype_Definition
=>
6636 Make_Attribute_Reference
(Loc
,
6637 Prefix
=> Make_Identifier
(Loc
, Chars
(A
)),
6638 Attribute_Name
=> Name_Range
))),
6640 Statements
=> New_List
(
6641 Make_Assignment_Statement
(Loc
,
6643 Expression
=> Make_Op_Not
(Loc
, A_J
))));
6645 Func_Name
:= Make_Defining_Identifier
(Loc
, New_Internal_Name
('N'));
6646 Set_Is_Inlined
(Func_Name
);
6649 Make_Subprogram_Body
(Loc
,
6651 Make_Function_Specification
(Loc
,
6652 Defining_Unit_Name
=> Func_Name
,
6653 Parameter_Specifications
=> New_List
(
6654 Make_Parameter_Specification
(Loc
,
6655 Defining_Identifier
=> A
,
6656 Parameter_Type
=> New_Reference_To
(Typ
, Loc
))),
6657 Result_Definition
=> New_Reference_To
(Typ
, Loc
)),
6659 Declarations
=> New_List
(
6660 Make_Object_Declaration
(Loc
,
6661 Defining_Identifier
=> B
,
6662 Object_Definition
=> New_Reference_To
(Arr
, Loc
))),
6664 Handled_Statement_Sequence
=>
6665 Make_Handled_Sequence_Of_Statements
(Loc
,
6666 Statements
=> New_List
(
6668 Make_Simple_Return_Statement
(Loc
,
6670 Make_Identifier
(Loc
, Chars
(B
)))))));
6673 Make_Function_Call
(Loc
,
6674 Name
=> New_Reference_To
(Func_Name
, Loc
),
6675 Parameter_Associations
=> New_List
(Opnd
)));
6677 Analyze_And_Resolve
(N
, Typ
);
6678 end Expand_N_Op_Not
;
6680 --------------------
6681 -- Expand_N_Op_Or --
6682 --------------------
6684 procedure Expand_N_Op_Or
(N
: Node_Id
) is
6685 Typ
: constant Entity_Id
:= Etype
(N
);
6688 Binary_Op_Validity_Checks
(N
);
6690 if Is_Array_Type
(Etype
(N
)) then
6691 Expand_Boolean_Operator
(N
);
6693 elsif Is_Boolean_Type
(Etype
(N
)) then
6694 Adjust_Condition
(Left_Opnd
(N
));
6695 Adjust_Condition
(Right_Opnd
(N
));
6696 Set_Etype
(N
, Standard_Boolean
);
6697 Adjust_Result_Type
(N
, Typ
);
6701 ----------------------
6702 -- Expand_N_Op_Plus --
6703 ----------------------
6705 procedure Expand_N_Op_Plus
(N
: Node_Id
) is
6707 Unary_Op_Validity_Checks
(N
);
6708 end Expand_N_Op_Plus
;
6710 ---------------------
6711 -- Expand_N_Op_Rem --
6712 ---------------------
6714 procedure Expand_N_Op_Rem
(N
: Node_Id
) is
6715 Loc
: constant Source_Ptr
:= Sloc
(N
);
6716 Typ
: constant Entity_Id
:= Etype
(N
);
6718 Left
: constant Node_Id
:= Left_Opnd
(N
);
6719 Right
: constant Node_Id
:= Right_Opnd
(N
);
6729 pragma Warnings
(Off
, Lhi
);
6732 Binary_Op_Validity_Checks
(N
);
6734 if Is_Integer_Type
(Etype
(N
)) then
6735 Apply_Divide_Check
(N
);
6738 -- Apply optimization x rem 1 = 0. We don't really need that with gcc,
6739 -- but it is useful with other back ends (e.g. AAMP), and is certainly
6742 if Is_Integer_Type
(Etype
(N
))
6743 and then Compile_Time_Known_Value
(Right
)
6744 and then Expr_Value
(Right
) = Uint_1
6746 -- Call Remove_Side_Effects to ensure that any side effects in the
6747 -- ignored left operand (in particular function calls to user defined
6748 -- functions) are properly executed.
6750 Remove_Side_Effects
(Left
);
6752 Rewrite
(N
, Make_Integer_Literal
(Loc
, 0));
6753 Analyze_And_Resolve
(N
, Typ
);
6757 -- Deal with annoying case of largest negative number remainder minus
6758 -- one. Gigi does not handle this case correctly, because it generates
6759 -- a divide instruction which may trap in this case.
6761 -- In fact the check is quite easy, if the right operand is -1, then
6762 -- the remainder is always 0, and we can just ignore the left operand
6763 -- completely in this case.
6765 Determine_Range
(Right
, ROK
, Rlo
, Rhi
);
6766 Determine_Range
(Left
, LOK
, Llo
, Lhi
);
6768 -- The operand type may be private (e.g. in the expansion of an
6769 -- intrinsic operation) so we must use the underlying type to get the
6770 -- bounds, and convert the literals explicitly.
6774 (Type_Low_Bound
(Base_Type
(Underlying_Type
(Etype
(Left
)))));
6776 -- Now perform the test, generating code only if needed
6778 if ((not ROK
) or else (Rlo
<= (-1) and then (-1) <= Rhi
))
6780 ((not LOK
) or else (Llo
= LLB
))
6783 Make_Conditional_Expression
(Loc
,
6784 Expressions
=> New_List
(
6786 Left_Opnd
=> Duplicate_Subexpr
(Right
),
6788 Unchecked_Convert_To
(Typ
,
6789 Make_Integer_Literal
(Loc
, -1))),
6791 Unchecked_Convert_To
(Typ
,
6792 Make_Integer_Literal
(Loc
, Uint_0
)),
6794 Relocate_Node
(N
))));
6796 Set_Analyzed
(Next
(Next
(First
(Expressions
(N
)))));
6797 Analyze_And_Resolve
(N
, Typ
);
6799 end Expand_N_Op_Rem
;
6801 -----------------------------
6802 -- Expand_N_Op_Rotate_Left --
6803 -----------------------------
6805 procedure Expand_N_Op_Rotate_Left
(N
: Node_Id
) is
6807 Binary_Op_Validity_Checks
(N
);
6808 end Expand_N_Op_Rotate_Left
;
6810 ------------------------------
6811 -- Expand_N_Op_Rotate_Right --
6812 ------------------------------
6814 procedure Expand_N_Op_Rotate_Right
(N
: Node_Id
) is
6816 Binary_Op_Validity_Checks
(N
);
6817 end Expand_N_Op_Rotate_Right
;
6819 ----------------------------
6820 -- Expand_N_Op_Shift_Left --
6821 ----------------------------
6823 procedure Expand_N_Op_Shift_Left
(N
: Node_Id
) is
6825 Binary_Op_Validity_Checks
(N
);
6826 end Expand_N_Op_Shift_Left
;
6828 -----------------------------
6829 -- Expand_N_Op_Shift_Right --
6830 -----------------------------
6832 procedure Expand_N_Op_Shift_Right
(N
: Node_Id
) is
6834 Binary_Op_Validity_Checks
(N
);
6835 end Expand_N_Op_Shift_Right
;
6837 ----------------------------------------
6838 -- Expand_N_Op_Shift_Right_Arithmetic --
6839 ----------------------------------------
6841 procedure Expand_N_Op_Shift_Right_Arithmetic
(N
: Node_Id
) is
6843 Binary_Op_Validity_Checks
(N
);
6844 end Expand_N_Op_Shift_Right_Arithmetic
;
6846 --------------------------
6847 -- Expand_N_Op_Subtract --
6848 --------------------------
6850 procedure Expand_N_Op_Subtract
(N
: Node_Id
) is
6851 Typ
: constant Entity_Id
:= Etype
(N
);
6854 Binary_Op_Validity_Checks
(N
);
6856 -- N - 0 = N for integer types
6858 if Is_Integer_Type
(Typ
)
6859 and then Compile_Time_Known_Value
(Right_Opnd
(N
))
6860 and then Expr_Value
(Right_Opnd
(N
)) = 0
6862 Rewrite
(N
, Left_Opnd
(N
));
6866 -- Arithmetic overflow checks for signed integer/fixed point types
6868 if Is_Signed_Integer_Type
(Typ
)
6869 or else Is_Fixed_Point_Type
(Typ
)
6871 Apply_Arithmetic_Overflow_Check
(N
);
6873 -- Vax floating-point types case
6875 elsif Vax_Float
(Typ
) then
6876 Expand_Vax_Arith
(N
);
6878 end Expand_N_Op_Subtract
;
6880 ---------------------
6881 -- Expand_N_Op_Xor --
6882 ---------------------
6884 procedure Expand_N_Op_Xor
(N
: Node_Id
) is
6885 Typ
: constant Entity_Id
:= Etype
(N
);
6888 Binary_Op_Validity_Checks
(N
);
6890 if Is_Array_Type
(Etype
(N
)) then
6891 Expand_Boolean_Operator
(N
);
6893 elsif Is_Boolean_Type
(Etype
(N
)) then
6894 Adjust_Condition
(Left_Opnd
(N
));
6895 Adjust_Condition
(Right_Opnd
(N
));
6896 Set_Etype
(N
, Standard_Boolean
);
6897 Adjust_Result_Type
(N
, Typ
);
6899 end Expand_N_Op_Xor
;
6901 ----------------------
6902 -- Expand_N_Or_Else --
6903 ----------------------
6905 -- Expand into conditional expression if Actions present, and also
6906 -- deal with optimizing case of arguments being True or False.
6908 procedure Expand_N_Or_Else
(N
: Node_Id
) is
6909 Loc
: constant Source_Ptr
:= Sloc
(N
);
6910 Typ
: constant Entity_Id
:= Etype
(N
);
6911 Left
: constant Node_Id
:= Left_Opnd
(N
);
6912 Right
: constant Node_Id
:= Right_Opnd
(N
);
6916 -- Deal with non-standard booleans
6918 if Is_Boolean_Type
(Typ
) then
6919 Adjust_Condition
(Left
);
6920 Adjust_Condition
(Right
);
6921 Set_Etype
(N
, Standard_Boolean
);
6924 -- Check for cases where left argument is known to be True or False
6926 if Compile_Time_Known_Value
(Left
) then
6928 -- If left argument is False, change (False or else Right) to Right.
6929 -- Any actions associated with Right will be executed unconditionally
6930 -- and can thus be inserted into the tree unconditionally.
6932 if Expr_Value_E
(Left
) = Standard_False
then
6933 if Present
(Actions
(N
)) then
6934 Insert_Actions
(N
, Actions
(N
));
6939 -- If left argument is True, change (True and then Right) to True. In
6940 -- this case we can forget the actions associated with Right, since
6941 -- they will never be executed.
6943 else pragma Assert
(Expr_Value_E
(Left
) = Standard_True
);
6944 Kill_Dead_Code
(Right
);
6945 Kill_Dead_Code
(Actions
(N
));
6946 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
6949 Adjust_Result_Type
(N
, Typ
);
6953 -- If Actions are present, we expand
6955 -- left or else right
6959 -- if left then True else right end
6961 -- with the actions becoming the Else_Actions of the conditional
6962 -- expression. This conditional expression is then further expanded
6963 -- (and will eventually disappear)
6965 if Present
(Actions
(N
)) then
6966 Actlist
:= Actions
(N
);
6968 Make_Conditional_Expression
(Loc
,
6969 Expressions
=> New_List
(
6971 New_Occurrence_Of
(Standard_True
, Loc
),
6974 Set_Else_Actions
(N
, Actlist
);
6975 Analyze_And_Resolve
(N
, Standard_Boolean
);
6976 Adjust_Result_Type
(N
, Typ
);
6980 -- No actions present, check for cases of right argument True/False
6982 if Compile_Time_Known_Value
(Right
) then
6984 -- Change (Left or else False) to Left. Note that we know there are
6985 -- no actions associated with the True operand, since we just checked
6986 -- for this case above.
6988 if Expr_Value_E
(Right
) = Standard_False
then
6991 -- Change (Left or else True) to True, making sure to preserve any
6992 -- side effects associated with the Left operand.
6994 else pragma Assert
(Expr_Value_E
(Right
) = Standard_True
);
6995 Remove_Side_Effects
(Left
);
6997 (N
, New_Occurrence_Of
(Standard_True
, Loc
));
7001 Adjust_Result_Type
(N
, Typ
);
7002 end Expand_N_Or_Else
;
7004 -----------------------------------
7005 -- Expand_N_Qualified_Expression --
7006 -----------------------------------
7008 procedure Expand_N_Qualified_Expression
(N
: Node_Id
) is
7009 Operand
: constant Node_Id
:= Expression
(N
);
7010 Target_Type
: constant Entity_Id
:= Entity
(Subtype_Mark
(N
));
7013 -- Do validity check if validity checking operands
7015 if Validity_Checks_On
7016 and then Validity_Check_Operands
7018 Ensure_Valid
(Operand
);
7021 -- Apply possible constraint check
7023 Apply_Constraint_Check
(Operand
, Target_Type
, No_Sliding
=> True);
7024 end Expand_N_Qualified_Expression
;
7026 ---------------------------------
7027 -- Expand_N_Selected_Component --
7028 ---------------------------------
7030 -- If the selector is a discriminant of a concurrent object, rewrite the
7031 -- prefix to denote the corresponding record type.
7033 procedure Expand_N_Selected_Component
(N
: Node_Id
) is
7034 Loc
: constant Source_Ptr
:= Sloc
(N
);
7035 Par
: constant Node_Id
:= Parent
(N
);
7036 P
: constant Node_Id
:= Prefix
(N
);
7037 Ptyp
: Entity_Id
:= Underlying_Type
(Etype
(P
));
7042 function In_Left_Hand_Side
(Comp
: Node_Id
) return Boolean;
7043 -- Gigi needs a temporary for prefixes that depend on a discriminant,
7044 -- unless the context of an assignment can provide size information.
7045 -- Don't we have a general routine that does this???
7047 -----------------------
7048 -- In_Left_Hand_Side --
7049 -----------------------
7051 function In_Left_Hand_Side
(Comp
: Node_Id
) return Boolean is
7053 return (Nkind
(Parent
(Comp
)) = N_Assignment_Statement
7054 and then Comp
= Name
(Parent
(Comp
)))
7055 or else (Present
(Parent
(Comp
))
7056 and then Nkind
(Parent
(Comp
)) in N_Subexpr
7057 and then In_Left_Hand_Side
(Parent
(Comp
)));
7058 end In_Left_Hand_Side
;
7060 -- Start of processing for Expand_N_Selected_Component
7063 -- Insert explicit dereference if required
7065 if Is_Access_Type
(Ptyp
) then
7066 Insert_Explicit_Dereference
(P
);
7067 Analyze_And_Resolve
(P
, Designated_Type
(Ptyp
));
7069 if Ekind
(Etype
(P
)) = E_Private_Subtype
7070 and then Is_For_Access_Subtype
(Etype
(P
))
7072 Set_Etype
(P
, Base_Type
(Etype
(P
)));
7078 -- Deal with discriminant check required
7080 if Do_Discriminant_Check
(N
) then
7082 -- Present the discriminant checking function to the backend, so that
7083 -- it can inline the call to the function.
7086 (Discriminant_Checking_Func
7087 (Original_Record_Component
(Entity
(Selector_Name
(N
)))));
7089 -- Now reset the flag and generate the call
7091 Set_Do_Discriminant_Check
(N
, False);
7092 Generate_Discriminant_Check
(N
);
7095 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
7096 -- function, then additional actuals must be passed.
7098 if Ada_Version
>= Ada_05
7099 and then Is_Build_In_Place_Function_Call
(P
)
7101 Make_Build_In_Place_Call_In_Anonymous_Context
(P
);
7104 -- Gigi cannot handle unchecked conversions that are the prefix of a
7105 -- selected component with discriminants. This must be checked during
7106 -- expansion, because during analysis the type of the selector is not
7107 -- known at the point the prefix is analyzed. If the conversion is the
7108 -- target of an assignment, then we cannot force the evaluation.
7110 if Nkind
(Prefix
(N
)) = N_Unchecked_Type_Conversion
7111 and then Has_Discriminants
(Etype
(N
))
7112 and then not In_Left_Hand_Side
(N
)
7114 Force_Evaluation
(Prefix
(N
));
7117 -- Remaining processing applies only if selector is a discriminant
7119 if Ekind
(Entity
(Selector_Name
(N
))) = E_Discriminant
then
7121 -- If the selector is a discriminant of a constrained record type,
7122 -- we may be able to rewrite the expression with the actual value
7123 -- of the discriminant, a useful optimization in some cases.
7125 if Is_Record_Type
(Ptyp
)
7126 and then Has_Discriminants
(Ptyp
)
7127 and then Is_Constrained
(Ptyp
)
7129 -- Do this optimization for discrete types only, and not for
7130 -- access types (access discriminants get us into trouble!)
7132 if not Is_Discrete_Type
(Etype
(N
)) then
7135 -- Don't do this on the left hand of an assignment statement.
7136 -- Normally one would think that references like this would
7137 -- not occur, but they do in generated code, and mean that
7138 -- we really do want to assign the discriminant!
7140 elsif Nkind
(Par
) = N_Assignment_Statement
7141 and then Name
(Par
) = N
7145 -- Don't do this optimization for the prefix of an attribute or
7146 -- the operand of an object renaming declaration since these are
7147 -- contexts where we do not want the value anyway.
7149 elsif (Nkind
(Par
) = N_Attribute_Reference
7150 and then Prefix
(Par
) = N
)
7151 or else Is_Renamed_Object
(N
)
7155 -- Don't do this optimization if we are within the code for a
7156 -- discriminant check, since the whole point of such a check may
7157 -- be to verify the condition on which the code below depends!
7159 elsif Is_In_Discriminant_Check
(N
) then
7162 -- Green light to see if we can do the optimization. There is
7163 -- still one condition that inhibits the optimization below but
7164 -- now is the time to check the particular discriminant.
7167 -- Loop through discriminants to find the matching discriminant
7168 -- constraint to see if we can copy it.
7170 Disc
:= First_Discriminant
(Ptyp
);
7171 Dcon
:= First_Elmt
(Discriminant_Constraint
(Ptyp
));
7172 Discr_Loop
: while Present
(Dcon
) loop
7174 -- Check if this is the matching discriminant
7176 if Disc
= Entity
(Selector_Name
(N
)) then
7178 -- Here we have the matching discriminant. Check for
7179 -- the case of a discriminant of a component that is
7180 -- constrained by an outer discriminant, which cannot
7181 -- be optimized away.
7184 Denotes_Discriminant
7185 (Node
(Dcon
), Check_Concurrent
=> True)
7189 -- In the context of a case statement, the expression may
7190 -- have the base type of the discriminant, and we need to
7191 -- preserve the constraint to avoid spurious errors on
7194 elsif Nkind
(Parent
(N
)) = N_Case_Statement
7195 and then Etype
(Node
(Dcon
)) /= Etype
(Disc
)
7198 Make_Qualified_Expression
(Loc
,
7200 New_Occurrence_Of
(Etype
(Disc
), Loc
),
7202 New_Copy_Tree
(Node
(Dcon
))));
7203 Analyze_And_Resolve
(N
, Etype
(Disc
));
7205 -- In case that comes out as a static expression,
7206 -- reset it (a selected component is never static).
7208 Set_Is_Static_Expression
(N
, False);
7211 -- Otherwise we can just copy the constraint, but the
7212 -- result is certainly not static! In some cases the
7213 -- discriminant constraint has been analyzed in the
7214 -- context of the original subtype indication, but for
7215 -- itypes the constraint might not have been analyzed
7216 -- yet, and this must be done now.
7219 Rewrite
(N
, New_Copy_Tree
(Node
(Dcon
)));
7220 Analyze_And_Resolve
(N
);
7221 Set_Is_Static_Expression
(N
, False);
7227 Next_Discriminant
(Disc
);
7228 end loop Discr_Loop
;
7230 -- Note: the above loop should always find a matching
7231 -- discriminant, but if it does not, we just missed an
7232 -- optimization due to some glitch (perhaps a previous error),
7238 -- The only remaining processing is in the case of a discriminant of
7239 -- a concurrent object, where we rewrite the prefix to denote the
7240 -- corresponding record type. If the type is derived and has renamed
7241 -- discriminants, use corresponding discriminant, which is the one
7242 -- that appears in the corresponding record.
7244 if not Is_Concurrent_Type
(Ptyp
) then
7248 Disc
:= Entity
(Selector_Name
(N
));
7250 if Is_Derived_Type
(Ptyp
)
7251 and then Present
(Corresponding_Discriminant
(Disc
))
7253 Disc
:= Corresponding_Discriminant
(Disc
);
7257 Make_Selected_Component
(Loc
,
7259 Unchecked_Convert_To
(Corresponding_Record_Type
(Ptyp
),
7261 Selector_Name
=> Make_Identifier
(Loc
, Chars
(Disc
)));
7266 end Expand_N_Selected_Component
;
7268 --------------------
7269 -- Expand_N_Slice --
7270 --------------------
7272 procedure Expand_N_Slice
(N
: Node_Id
) is
7273 Loc
: constant Source_Ptr
:= Sloc
(N
);
7274 Typ
: constant Entity_Id
:= Etype
(N
);
7275 Pfx
: constant Node_Id
:= Prefix
(N
);
7276 Ptp
: Entity_Id
:= Etype
(Pfx
);
7278 function Is_Procedure_Actual
(N
: Node_Id
) return Boolean;
7279 -- Check whether the argument is an actual for a procedure call, in
7280 -- which case the expansion of a bit-packed slice is deferred until the
7281 -- call itself is expanded. The reason this is required is that we might
7282 -- have an IN OUT or OUT parameter, and the copy out is essential, and
7283 -- that copy out would be missed if we created a temporary here in
7284 -- Expand_N_Slice. Note that we don't bother to test specifically for an
7285 -- IN OUT or OUT mode parameter, since it is a bit tricky to do, and it
7286 -- is harmless to defer expansion in the IN case, since the call
7287 -- processing will still generate the appropriate copy in operation,
7288 -- which will take care of the slice.
7290 procedure Make_Temporary
;
7291 -- Create a named variable for the value of the slice, in cases where
7292 -- the back-end cannot handle it properly, e.g. when packed types or
7293 -- unaligned slices are involved.
7295 -------------------------
7296 -- Is_Procedure_Actual --
7297 -------------------------
7299 function Is_Procedure_Actual
(N
: Node_Id
) return Boolean is
7300 Par
: Node_Id
:= Parent
(N
);
7304 -- If our parent is a procedure call we can return
7306 if Nkind
(Par
) = N_Procedure_Call_Statement
then
7309 -- If our parent is a type conversion, keep climbing the tree,
7310 -- since a type conversion can be a procedure actual. Also keep
7311 -- climbing if parameter association or a qualified expression,
7312 -- since these are additional cases that do can appear on
7313 -- procedure actuals.
7315 elsif Nkind_In
(Par
, N_Type_Conversion
,
7316 N_Parameter_Association
,
7317 N_Qualified_Expression
)
7319 Par
:= Parent
(Par
);
7321 -- Any other case is not what we are looking for
7327 end Is_Procedure_Actual
;
7329 --------------------
7330 -- Make_Temporary --
7331 --------------------
7333 procedure Make_Temporary
is
7335 Ent
: constant Entity_Id
:=
7336 Make_Defining_Identifier
(Loc
, New_Internal_Name
('T'));
7339 Make_Object_Declaration
(Loc
,
7340 Defining_Identifier
=> Ent
,
7341 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
));
7343 Set_No_Initialization
(Decl
);
7345 Insert_Actions
(N
, New_List
(
7347 Make_Assignment_Statement
(Loc
,
7348 Name
=> New_Occurrence_Of
(Ent
, Loc
),
7349 Expression
=> Relocate_Node
(N
))));
7351 Rewrite
(N
, New_Occurrence_Of
(Ent
, Loc
));
7352 Analyze_And_Resolve
(N
, Typ
);
7355 -- Start of processing for Expand_N_Slice
7358 -- Special handling for access types
7360 if Is_Access_Type
(Ptp
) then
7362 Ptp
:= Designated_Type
(Ptp
);
7365 Make_Explicit_Dereference
(Sloc
(N
),
7366 Prefix
=> Relocate_Node
(Pfx
)));
7368 Analyze_And_Resolve
(Pfx
, Ptp
);
7371 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
7372 -- function, then additional actuals must be passed.
7374 if Ada_Version
>= Ada_05
7375 and then Is_Build_In_Place_Function_Call
(Pfx
)
7377 Make_Build_In_Place_Call_In_Anonymous_Context
(Pfx
);
7380 -- Range checks are potentially also needed for cases involving a slice
7381 -- indexed by a subtype indication, but Do_Range_Check can currently
7382 -- only be set for expressions ???
7384 if not Index_Checks_Suppressed
(Ptp
)
7385 and then (not Is_Entity_Name
(Pfx
)
7386 or else not Index_Checks_Suppressed
(Entity
(Pfx
)))
7387 and then Nkind
(Discrete_Range
(N
)) /= N_Subtype_Indication
7389 -- Do not enable range check to nodes associated with the frontend
7390 -- expansion of the dispatch table. We first check if Ada.Tags is
7391 -- already loaded to avoid the addition of an undesired dependence
7392 -- on such run-time unit.
7395 (not Tagged_Type_Expansion
7397 (RTU_Loaded
(Ada_Tags
)
7398 and then Nkind
(Prefix
(N
)) = N_Selected_Component
7399 and then Present
(Entity
(Selector_Name
(Prefix
(N
))))
7400 and then Entity
(Selector_Name
(Prefix
(N
))) =
7401 RTE_Record_Component
(RE_Prims_Ptr
)))
7403 Enable_Range_Check
(Discrete_Range
(N
));
7406 -- The remaining case to be handled is packed slices. We can leave
7407 -- packed slices as they are in the following situations:
7409 -- 1. Right or left side of an assignment (we can handle this
7410 -- situation correctly in the assignment statement expansion).
7412 -- 2. Prefix of indexed component (the slide is optimized away in this
7413 -- case, see the start of Expand_N_Slice.)
7415 -- 3. Object renaming declaration, since we want the name of the
7416 -- slice, not the value.
7418 -- 4. Argument to procedure call, since copy-in/copy-out handling may
7419 -- be required, and this is handled in the expansion of call
7422 -- 5. Prefix of an address attribute (this is an error which is caught
7423 -- elsewhere, and the expansion would interfere with generating the
7426 if not Is_Packed
(Typ
) then
7428 -- Apply transformation for actuals of a function call, where
7429 -- Expand_Actuals is not used.
7431 if Nkind
(Parent
(N
)) = N_Function_Call
7432 and then Is_Possibly_Unaligned_Slice
(N
)
7437 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
7438 or else (Nkind
(Parent
(Parent
(N
))) = N_Assignment_Statement
7439 and then Parent
(N
) = Name
(Parent
(Parent
(N
))))
7443 elsif Nkind
(Parent
(N
)) = N_Indexed_Component
7444 or else Is_Renamed_Object
(N
)
7445 or else Is_Procedure_Actual
(N
)
7449 elsif Nkind
(Parent
(N
)) = N_Attribute_Reference
7450 and then Attribute_Name
(Parent
(N
)) = Name_Address
7459 ------------------------------
7460 -- Expand_N_Type_Conversion --
7461 ------------------------------
7463 procedure Expand_N_Type_Conversion
(N
: Node_Id
) is
7464 Loc
: constant Source_Ptr
:= Sloc
(N
);
7465 Operand
: constant Node_Id
:= Expression
(N
);
7466 Target_Type
: constant Entity_Id
:= Etype
(N
);
7467 Operand_Type
: Entity_Id
:= Etype
(Operand
);
7469 procedure Handle_Changed_Representation
;
7470 -- This is called in the case of record and array type conversions to
7471 -- see if there is a change of representation to be handled. Change of
7472 -- representation is actually handled at the assignment statement level,
7473 -- and what this procedure does is rewrite node N conversion as an
7474 -- assignment to temporary. If there is no change of representation,
7475 -- then the conversion node is unchanged.
7477 procedure Real_Range_Check
;
7478 -- Handles generation of range check for real target value
7480 -----------------------------------
7481 -- Handle_Changed_Representation --
7482 -----------------------------------
7484 procedure Handle_Changed_Representation
is
7493 -- Nothing else to do if no change of representation
7495 if Same_Representation
(Operand_Type
, Target_Type
) then
7498 -- The real change of representation work is done by the assignment
7499 -- statement processing. So if this type conversion is appearing as
7500 -- the expression of an assignment statement, nothing needs to be
7501 -- done to the conversion.
7503 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
then
7506 -- Otherwise we need to generate a temporary variable, and do the
7507 -- change of representation assignment into that temporary variable.
7508 -- The conversion is then replaced by a reference to this variable.
7513 -- If type is unconstrained we have to add a constraint, copied
7514 -- from the actual value of the left hand side.
7516 if not Is_Constrained
(Target_Type
) then
7517 if Has_Discriminants
(Operand_Type
) then
7518 Disc
:= First_Discriminant
(Operand_Type
);
7520 if Disc
/= First_Stored_Discriminant
(Operand_Type
) then
7521 Disc
:= First_Stored_Discriminant
(Operand_Type
);
7525 while Present
(Disc
) loop
7527 Make_Selected_Component
(Loc
,
7528 Prefix
=> Duplicate_Subexpr_Move_Checks
(Operand
),
7530 Make_Identifier
(Loc
, Chars
(Disc
))));
7531 Next_Discriminant
(Disc
);
7534 elsif Is_Array_Type
(Operand_Type
) then
7535 N_Ix
:= First_Index
(Target_Type
);
7538 for J
in 1 .. Number_Dimensions
(Operand_Type
) loop
7540 -- We convert the bounds explicitly. We use an unchecked
7541 -- conversion because bounds checks are done elsewhere.
7546 Unchecked_Convert_To
(Etype
(N_Ix
),
7547 Make_Attribute_Reference
(Loc
,
7549 Duplicate_Subexpr_No_Checks
7550 (Operand
, Name_Req
=> True),
7551 Attribute_Name
=> Name_First
,
7552 Expressions
=> New_List
(
7553 Make_Integer_Literal
(Loc
, J
)))),
7556 Unchecked_Convert_To
(Etype
(N_Ix
),
7557 Make_Attribute_Reference
(Loc
,
7559 Duplicate_Subexpr_No_Checks
7560 (Operand
, Name_Req
=> True),
7561 Attribute_Name
=> Name_Last
,
7562 Expressions
=> New_List
(
7563 Make_Integer_Literal
(Loc
, J
))))));
7570 Odef
:= New_Occurrence_Of
(Target_Type
, Loc
);
7572 if Present
(Cons
) then
7574 Make_Subtype_Indication
(Loc
,
7575 Subtype_Mark
=> Odef
,
7577 Make_Index_Or_Discriminant_Constraint
(Loc
,
7578 Constraints
=> Cons
));
7581 Temp
:= Make_Defining_Identifier
(Loc
, New_Internal_Name
('C'));
7583 Make_Object_Declaration
(Loc
,
7584 Defining_Identifier
=> Temp
,
7585 Object_Definition
=> Odef
);
7587 Set_No_Initialization
(Decl
, True);
7589 -- Insert required actions. It is essential to suppress checks
7590 -- since we have suppressed default initialization, which means
7591 -- that the variable we create may have no discriminants.
7596 Make_Assignment_Statement
(Loc
,
7597 Name
=> New_Occurrence_Of
(Temp
, Loc
),
7598 Expression
=> Relocate_Node
(N
))),
7599 Suppress
=> All_Checks
);
7601 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
7604 end Handle_Changed_Representation
;
7606 ----------------------
7607 -- Real_Range_Check --
7608 ----------------------
7610 -- Case of conversions to floating-point or fixed-point. If range checks
7611 -- are enabled and the target type has a range constraint, we convert:
7617 -- Tnn : typ'Base := typ'Base (x);
7618 -- [constraint_error when Tnn < typ'First or else Tnn > typ'Last]
7621 -- This is necessary when there is a conversion of integer to float or
7622 -- to fixed-point to ensure that the correct checks are made. It is not
7623 -- necessary for float to float where it is enough to simply set the
7624 -- Do_Range_Check flag.
7626 procedure Real_Range_Check
is
7627 Btyp
: constant Entity_Id
:= Base_Type
(Target_Type
);
7628 Lo
: constant Node_Id
:= Type_Low_Bound
(Target_Type
);
7629 Hi
: constant Node_Id
:= Type_High_Bound
(Target_Type
);
7630 Xtyp
: constant Entity_Id
:= Etype
(Operand
);
7635 -- Nothing to do if conversion was rewritten
7637 if Nkind
(N
) /= N_Type_Conversion
then
7641 -- Nothing to do if range checks suppressed, or target has the same
7642 -- range as the base type (or is the base type).
7644 if Range_Checks_Suppressed
(Target_Type
)
7645 or else (Lo
= Type_Low_Bound
(Btyp
)
7647 Hi
= Type_High_Bound
(Btyp
))
7652 -- Nothing to do if expression is an entity on which checks have been
7655 if Is_Entity_Name
(Operand
)
7656 and then Range_Checks_Suppressed
(Entity
(Operand
))
7661 -- Nothing to do if bounds are all static and we can tell that the
7662 -- expression is within the bounds of the target. Note that if the
7663 -- operand is of an unconstrained floating-point type, then we do
7664 -- not trust it to be in range (might be infinite)
7667 S_Lo
: constant Node_Id
:= Type_Low_Bound
(Xtyp
);
7668 S_Hi
: constant Node_Id
:= Type_High_Bound
(Xtyp
);
7671 if (not Is_Floating_Point_Type
(Xtyp
)
7672 or else Is_Constrained
(Xtyp
))
7673 and then Compile_Time_Known_Value
(S_Lo
)
7674 and then Compile_Time_Known_Value
(S_Hi
)
7675 and then Compile_Time_Known_Value
(Hi
)
7676 and then Compile_Time_Known_Value
(Lo
)
7679 D_Lov
: constant Ureal
:= Expr_Value_R
(Lo
);
7680 D_Hiv
: constant Ureal
:= Expr_Value_R
(Hi
);
7685 if Is_Real_Type
(Xtyp
) then
7686 S_Lov
:= Expr_Value_R
(S_Lo
);
7687 S_Hiv
:= Expr_Value_R
(S_Hi
);
7689 S_Lov
:= UR_From_Uint
(Expr_Value
(S_Lo
));
7690 S_Hiv
:= UR_From_Uint
(Expr_Value
(S_Hi
));
7694 and then S_Lov
>= D_Lov
7695 and then S_Hiv
<= D_Hiv
7697 Set_Do_Range_Check
(Operand
, False);
7704 -- For float to float conversions, we are done
7706 if Is_Floating_Point_Type
(Xtyp
)
7708 Is_Floating_Point_Type
(Btyp
)
7713 -- Otherwise rewrite the conversion as described above
7715 Conv
:= Relocate_Node
(N
);
7717 (Subtype_Mark
(Conv
), New_Occurrence_Of
(Btyp
, Loc
));
7718 Set_Etype
(Conv
, Btyp
);
7720 -- Enable overflow except for case of integer to float conversions,
7721 -- where it is never required, since we can never have overflow in
7724 if not Is_Integer_Type
(Etype
(Operand
)) then
7725 Enable_Overflow_Check
(Conv
);
7729 Make_Defining_Identifier
(Loc
,
7730 Chars
=> New_Internal_Name
('T'));
7732 Insert_Actions
(N
, New_List
(
7733 Make_Object_Declaration
(Loc
,
7734 Defining_Identifier
=> Tnn
,
7735 Object_Definition
=> New_Occurrence_Of
(Btyp
, Loc
),
7736 Expression
=> Conv
),
7738 Make_Raise_Constraint_Error
(Loc
,
7743 Left_Opnd
=> New_Occurrence_Of
(Tnn
, Loc
),
7745 Make_Attribute_Reference
(Loc
,
7746 Attribute_Name
=> Name_First
,
7748 New_Occurrence_Of
(Target_Type
, Loc
))),
7752 Left_Opnd
=> New_Occurrence_Of
(Tnn
, Loc
),
7754 Make_Attribute_Reference
(Loc
,
7755 Attribute_Name
=> Name_Last
,
7757 New_Occurrence_Of
(Target_Type
, Loc
)))),
7758 Reason
=> CE_Range_Check_Failed
)));
7760 Rewrite
(N
, New_Occurrence_Of
(Tnn
, Loc
));
7761 Analyze_And_Resolve
(N
, Btyp
);
7762 end Real_Range_Check
;
7764 -- Start of processing for Expand_N_Type_Conversion
7767 -- Nothing at all to do if conversion is to the identical type so remove
7768 -- the conversion completely, it is useless.
7770 if Operand_Type
= Target_Type
then
7771 Rewrite
(N
, Relocate_Node
(Operand
));
7775 -- Nothing to do if this is the second argument of read. This is a
7776 -- "backwards" conversion that will be handled by the specialized code
7777 -- in attribute processing.
7779 if Nkind
(Parent
(N
)) = N_Attribute_Reference
7780 and then Attribute_Name
(Parent
(N
)) = Name_Read
7781 and then Next
(First
(Expressions
(Parent
(N
)))) = N
7786 -- Here if we may need to expand conversion
7788 -- Do validity check if validity checking operands
7790 if Validity_Checks_On
7791 and then Validity_Check_Operands
7793 Ensure_Valid
(Operand
);
7796 -- Special case of converting from non-standard boolean type
7798 if Is_Boolean_Type
(Operand_Type
)
7799 and then (Nonzero_Is_True
(Operand_Type
))
7801 Adjust_Condition
(Operand
);
7802 Set_Etype
(Operand
, Standard_Boolean
);
7803 Operand_Type
:= Standard_Boolean
;
7806 -- Case of converting to an access type
7808 if Is_Access_Type
(Target_Type
) then
7810 -- Apply an accessibility check when the conversion operand is an
7811 -- access parameter (or a renaming thereof), unless conversion was
7812 -- expanded from an Unchecked_ or Unrestricted_Access attribute.
7813 -- Note that other checks may still need to be applied below (such
7814 -- as tagged type checks).
7816 if Is_Entity_Name
(Operand
)
7818 (Is_Formal
(Entity
(Operand
))
7820 (Present
(Renamed_Object
(Entity
(Operand
)))
7821 and then Is_Entity_Name
(Renamed_Object
(Entity
(Operand
)))
7823 (Entity
(Renamed_Object
(Entity
(Operand
))))))
7824 and then Ekind
(Etype
(Operand
)) = E_Anonymous_Access_Type
7825 and then (Nkind
(Original_Node
(N
)) /= N_Attribute_Reference
7826 or else Attribute_Name
(Original_Node
(N
)) = Name_Access
)
7828 Apply_Accessibility_Check
7829 (Operand
, Target_Type
, Insert_Node
=> Operand
);
7831 -- If the level of the operand type is statically deeper than the
7832 -- level of the target type, then force Program_Error. Note that this
7833 -- can only occur for cases where the attribute is within the body of
7834 -- an instantiation (otherwise the conversion will already have been
7835 -- rejected as illegal). Note: warnings are issued by the analyzer
7836 -- for the instance cases.
7838 elsif In_Instance_Body
7839 and then Type_Access_Level
(Operand_Type
) >
7840 Type_Access_Level
(Target_Type
)
7843 Make_Raise_Program_Error
(Sloc
(N
),
7844 Reason
=> PE_Accessibility_Check_Failed
));
7845 Set_Etype
(N
, Target_Type
);
7847 -- When the operand is a selected access discriminant the check needs
7848 -- to be made against the level of the object denoted by the prefix
7849 -- of the selected name. Force Program_Error for this case as well
7850 -- (this accessibility violation can only happen if within the body
7851 -- of an instantiation).
7853 elsif In_Instance_Body
7854 and then Ekind
(Operand_Type
) = E_Anonymous_Access_Type
7855 and then Nkind
(Operand
) = N_Selected_Component
7856 and then Object_Access_Level
(Operand
) >
7857 Type_Access_Level
(Target_Type
)
7860 Make_Raise_Program_Error
(Sloc
(N
),
7861 Reason
=> PE_Accessibility_Check_Failed
));
7862 Set_Etype
(N
, Target_Type
);
7866 -- Case of conversions of tagged types and access to tagged types
7868 -- When needed, that is to say when the expression is class-wide, Add
7869 -- runtime a tag check for (strict) downward conversion by using the
7870 -- membership test, generating:
7872 -- [constraint_error when Operand not in Target_Type'Class]
7874 -- or in the access type case
7876 -- [constraint_error
7877 -- when Operand /= null
7878 -- and then Operand.all not in
7879 -- Designated_Type (Target_Type)'Class]
7881 if (Is_Access_Type
(Target_Type
)
7882 and then Is_Tagged_Type
(Designated_Type
(Target_Type
)))
7883 or else Is_Tagged_Type
(Target_Type
)
7885 -- Do not do any expansion in the access type case if the parent is a
7886 -- renaming, since this is an error situation which will be caught by
7887 -- Sem_Ch8, and the expansion can interfere with this error check.
7889 if Is_Access_Type
(Target_Type
)
7890 and then Is_Renamed_Object
(N
)
7895 -- Otherwise, proceed with processing tagged conversion
7898 Actual_Op_Typ
: Entity_Id
;
7899 Actual_Targ_Typ
: Entity_Id
;
7900 Make_Conversion
: Boolean := False;
7901 Root_Op_Typ
: Entity_Id
;
7903 procedure Make_Tag_Check
(Targ_Typ
: Entity_Id
);
7904 -- Create a membership check to test whether Operand is a member
7905 -- of Targ_Typ. If the original Target_Type is an access, include
7906 -- a test for null value. The check is inserted at N.
7908 --------------------
7909 -- Make_Tag_Check --
7910 --------------------
7912 procedure Make_Tag_Check
(Targ_Typ
: Entity_Id
) is
7917 -- [Constraint_Error
7918 -- when Operand /= null
7919 -- and then Operand.all not in Targ_Typ]
7921 if Is_Access_Type
(Target_Type
) then
7926 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Operand
),
7927 Right_Opnd
=> Make_Null
(Loc
)),
7932 Make_Explicit_Dereference
(Loc
,
7933 Prefix
=> Duplicate_Subexpr_No_Checks
(Operand
)),
7934 Right_Opnd
=> New_Reference_To
(Targ_Typ
, Loc
)));
7937 -- [Constraint_Error when Operand not in Targ_Typ]
7942 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Operand
),
7943 Right_Opnd
=> New_Reference_To
(Targ_Typ
, Loc
));
7947 Make_Raise_Constraint_Error
(Loc
,
7949 Reason
=> CE_Tag_Check_Failed
));
7952 -- Start of processing
7955 if Is_Access_Type
(Target_Type
) then
7956 Actual_Op_Typ
:= Designated_Type
(Operand_Type
);
7957 Actual_Targ_Typ
:= Designated_Type
(Target_Type
);
7960 Actual_Op_Typ
:= Operand_Type
;
7961 Actual_Targ_Typ
:= Target_Type
;
7964 Root_Op_Typ
:= Root_Type
(Actual_Op_Typ
);
7966 -- Ada 2005 (AI-251): Handle interface type conversion
7968 if Is_Interface
(Actual_Op_Typ
) then
7969 Expand_Interface_Conversion
(N
, Is_Static
=> False);
7973 if not Tag_Checks_Suppressed
(Actual_Targ_Typ
) then
7975 -- Create a runtime tag check for a downward class-wide type
7978 if Is_Class_Wide_Type
(Actual_Op_Typ
)
7979 and then Root_Op_Typ
/= Actual_Targ_Typ
7980 and then Is_Ancestor
(Root_Op_Typ
, Actual_Targ_Typ
)
7982 Make_Tag_Check
(Class_Wide_Type
(Actual_Targ_Typ
));
7983 Make_Conversion
:= True;
7986 -- AI05-0073: If the result subtype of the function is defined
7987 -- by an access_definition designating a specific tagged type
7988 -- T, a check is made that the result value is null or the tag
7989 -- of the object designated by the result value identifies T.
7990 -- Constraint_Error is raised if this check fails.
7992 if Nkind
(Parent
(N
)) = Sinfo
.N_Return_Statement
then
7995 Func_Typ
: Entity_Id
;
7998 -- Climb scope stack looking for the enclosing function
8000 Func
:= Current_Scope
;
8001 while Present
(Func
)
8002 and then Ekind
(Func
) /= E_Function
8004 Func
:= Scope
(Func
);
8007 -- The function's return subtype must be defined using
8008 -- an access definition.
8010 if Nkind
(Result_Definition
(Parent
(Func
))) =
8013 Func_Typ
:= Directly_Designated_Type
(Etype
(Func
));
8015 -- The return subtype denotes a specific tagged type,
8016 -- in other words, a non class-wide type.
8018 if Is_Tagged_Type
(Func_Typ
)
8019 and then not Is_Class_Wide_Type
(Func_Typ
)
8021 Make_Tag_Check
(Actual_Targ_Typ
);
8022 Make_Conversion
:= True;
8028 -- We have generated a tag check for either a class-wide type
8029 -- conversion or for AI05-0073.
8031 if Make_Conversion
then
8036 Make_Unchecked_Type_Conversion
(Loc
,
8037 Subtype_Mark
=> New_Occurrence_Of
(Target_Type
, Loc
),
8038 Expression
=> Relocate_Node
(Expression
(N
)));
8040 Analyze_And_Resolve
(N
, Target_Type
);
8046 -- Case of other access type conversions
8048 elsif Is_Access_Type
(Target_Type
) then
8049 Apply_Constraint_Check
(Operand
, Target_Type
);
8051 -- Case of conversions from a fixed-point type
8053 -- These conversions require special expansion and processing, found in
8054 -- the Exp_Fixd package. We ignore cases where Conversion_OK is set,
8055 -- since from a semantic point of view, these are simple integer
8056 -- conversions, which do not need further processing.
8058 elsif Is_Fixed_Point_Type
(Operand_Type
)
8059 and then not Conversion_OK
(N
)
8061 -- We should never see universal fixed at this case, since the
8062 -- expansion of the constituent divide or multiply should have
8063 -- eliminated the explicit mention of universal fixed.
8065 pragma Assert
(Operand_Type
/= Universal_Fixed
);
8067 -- Check for special case of the conversion to universal real that
8068 -- occurs as a result of the use of a round attribute. In this case,
8069 -- the real type for the conversion is taken from the target type of
8070 -- the Round attribute and the result must be marked as rounded.
8072 if Target_Type
= Universal_Real
8073 and then Nkind
(Parent
(N
)) = N_Attribute_Reference
8074 and then Attribute_Name
(Parent
(N
)) = Name_Round
8076 Set_Rounded_Result
(N
);
8077 Set_Etype
(N
, Etype
(Parent
(N
)));
8080 -- Otherwise do correct fixed-conversion, but skip these if the
8081 -- Conversion_OK flag is set, because from a semantic point of
8082 -- view these are simple integer conversions needing no further
8083 -- processing (the backend will simply treat them as integers)
8085 if not Conversion_OK
(N
) then
8086 if Is_Fixed_Point_Type
(Etype
(N
)) then
8087 Expand_Convert_Fixed_To_Fixed
(N
);
8090 elsif Is_Integer_Type
(Etype
(N
)) then
8091 Expand_Convert_Fixed_To_Integer
(N
);
8094 pragma Assert
(Is_Floating_Point_Type
(Etype
(N
)));
8095 Expand_Convert_Fixed_To_Float
(N
);
8100 -- Case of conversions to a fixed-point type
8102 -- These conversions require special expansion and processing, found in
8103 -- the Exp_Fixd package. Again, ignore cases where Conversion_OK is set,
8104 -- since from a semantic point of view, these are simple integer
8105 -- conversions, which do not need further processing.
8107 elsif Is_Fixed_Point_Type
(Target_Type
)
8108 and then not Conversion_OK
(N
)
8110 if Is_Integer_Type
(Operand_Type
) then
8111 Expand_Convert_Integer_To_Fixed
(N
);
8114 pragma Assert
(Is_Floating_Point_Type
(Operand_Type
));
8115 Expand_Convert_Float_To_Fixed
(N
);
8119 -- Case of float-to-integer conversions
8121 -- We also handle float-to-fixed conversions with Conversion_OK set
8122 -- since semantically the fixed-point target is treated as though it
8123 -- were an integer in such cases.
8125 elsif Is_Floating_Point_Type
(Operand_Type
)
8127 (Is_Integer_Type
(Target_Type
)
8129 (Is_Fixed_Point_Type
(Target_Type
) and then Conversion_OK
(N
)))
8131 -- One more check here, gcc is still not able to do conversions of
8132 -- this type with proper overflow checking, and so gigi is doing an
8133 -- approximation of what is required by doing floating-point compares
8134 -- with the end-point. But that can lose precision in some cases, and
8135 -- give a wrong result. Converting the operand to Universal_Real is
8136 -- helpful, but still does not catch all cases with 64-bit integers
8137 -- on targets with only 64-bit floats
8139 -- The above comment seems obsoleted by Apply_Float_Conversion_Check
8140 -- Can this code be removed ???
8142 if Do_Range_Check
(Operand
) then
8144 Make_Type_Conversion
(Loc
,
8146 New_Occurrence_Of
(Universal_Real
, Loc
),
8148 Relocate_Node
(Operand
)));
8150 Set_Etype
(Operand
, Universal_Real
);
8151 Enable_Range_Check
(Operand
);
8152 Set_Do_Range_Check
(Expression
(Operand
), False);
8155 -- Case of array conversions
8157 -- Expansion of array conversions, add required length/range checks but
8158 -- only do this if there is no change of representation. For handling of
8159 -- this case, see Handle_Changed_Representation.
8161 elsif Is_Array_Type
(Target_Type
) then
8163 if Is_Constrained
(Target_Type
) then
8164 Apply_Length_Check
(Operand
, Target_Type
);
8166 Apply_Range_Check
(Operand
, Target_Type
);
8169 Handle_Changed_Representation
;
8171 -- Case of conversions of discriminated types
8173 -- Add required discriminant checks if target is constrained. Again this
8174 -- change is skipped if we have a change of representation.
8176 elsif Has_Discriminants
(Target_Type
)
8177 and then Is_Constrained
(Target_Type
)
8179 Apply_Discriminant_Check
(Operand
, Target_Type
);
8180 Handle_Changed_Representation
;
8182 -- Case of all other record conversions. The only processing required
8183 -- is to check for a change of representation requiring the special
8184 -- assignment processing.
8186 elsif Is_Record_Type
(Target_Type
) then
8188 -- Ada 2005 (AI-216): Program_Error is raised when converting from
8189 -- a derived Unchecked_Union type to an unconstrained type that is
8190 -- not Unchecked_Union if the operand lacks inferable discriminants.
8192 if Is_Derived_Type
(Operand_Type
)
8193 and then Is_Unchecked_Union
(Base_Type
(Operand_Type
))
8194 and then not Is_Constrained
(Target_Type
)
8195 and then not Is_Unchecked_Union
(Base_Type
(Target_Type
))
8196 and then not Has_Inferable_Discriminants
(Operand
)
8198 -- To prevent Gigi from generating illegal code, we generate a
8199 -- Program_Error node, but we give it the target type of the
8203 PE
: constant Node_Id
:= Make_Raise_Program_Error
(Loc
,
8204 Reason
=> PE_Unchecked_Union_Restriction
);
8207 Set_Etype
(PE
, Target_Type
);
8212 Handle_Changed_Representation
;
8215 -- Case of conversions of enumeration types
8217 elsif Is_Enumeration_Type
(Target_Type
) then
8219 -- Special processing is required if there is a change of
8220 -- representation (from enumeration representation clauses)
8222 if not Same_Representation
(Target_Type
, Operand_Type
) then
8224 -- Convert: x(y) to x'val (ytyp'val (y))
8227 Make_Attribute_Reference
(Loc
,
8228 Prefix
=> New_Occurrence_Of
(Target_Type
, Loc
),
8229 Attribute_Name
=> Name_Val
,
8230 Expressions
=> New_List
(
8231 Make_Attribute_Reference
(Loc
,
8232 Prefix
=> New_Occurrence_Of
(Operand_Type
, Loc
),
8233 Attribute_Name
=> Name_Pos
,
8234 Expressions
=> New_List
(Operand
)))));
8236 Analyze_And_Resolve
(N
, Target_Type
);
8239 -- Case of conversions to floating-point
8241 elsif Is_Floating_Point_Type
(Target_Type
) then
8245 -- At this stage, either the conversion node has been transformed into
8246 -- some other equivalent expression, or left as a conversion that can
8247 -- be handled by Gigi. The conversions that Gigi can handle are the
8250 -- Conversions with no change of representation or type
8252 -- Numeric conversions involving integer, floating- and fixed-point
8253 -- values. Fixed-point values are allowed only if Conversion_OK is
8254 -- set, i.e. if the fixed-point values are to be treated as integers.
8256 -- No other conversions should be passed to Gigi
8258 -- Check: are these rules stated in sinfo??? if so, why restate here???
8260 -- The only remaining step is to generate a range check if we still have
8261 -- a type conversion at this stage and Do_Range_Check is set. For now we
8262 -- do this only for conversions of discrete types.
8264 if Nkind
(N
) = N_Type_Conversion
8265 and then Is_Discrete_Type
(Etype
(N
))
8268 Expr
: constant Node_Id
:= Expression
(N
);
8273 if Do_Range_Check
(Expr
)
8274 and then Is_Discrete_Type
(Etype
(Expr
))
8276 Set_Do_Range_Check
(Expr
, False);
8278 -- Before we do a range check, we have to deal with treating a
8279 -- fixed-point operand as an integer. The way we do this is
8280 -- simply to do an unchecked conversion to an appropriate
8281 -- integer type large enough to hold the result.
8283 -- This code is not active yet, because we are only dealing
8284 -- with discrete types so far ???
8286 if Nkind
(Expr
) in N_Has_Treat_Fixed_As_Integer
8287 and then Treat_Fixed_As_Integer
(Expr
)
8289 Ftyp
:= Base_Type
(Etype
(Expr
));
8291 if Esize
(Ftyp
) >= Esize
(Standard_Integer
) then
8292 Ityp
:= Standard_Long_Long_Integer
;
8294 Ityp
:= Standard_Integer
;
8297 Rewrite
(Expr
, Unchecked_Convert_To
(Ityp
, Expr
));
8300 -- Reset overflow flag, since the range check will include
8301 -- dealing with possible overflow, and generate the check If
8302 -- Address is either a source type or target type, suppress
8303 -- range check to avoid typing anomalies when it is a visible
8306 Set_Do_Overflow_Check
(N
, False);
8307 if not Is_Descendent_Of_Address
(Etype
(Expr
))
8308 and then not Is_Descendent_Of_Address
(Target_Type
)
8310 Generate_Range_Check
8311 (Expr
, Target_Type
, CE_Range_Check_Failed
);
8317 -- Final step, if the result is a type conversion involving Vax_Float
8318 -- types, then it is subject for further special processing.
8320 if Nkind
(N
) = N_Type_Conversion
8321 and then (Vax_Float
(Operand_Type
) or else Vax_Float
(Target_Type
))
8323 Expand_Vax_Conversion
(N
);
8326 end Expand_N_Type_Conversion
;
8328 -----------------------------------
8329 -- Expand_N_Unchecked_Expression --
8330 -----------------------------------
8332 -- Remove the unchecked expression node from the tree. It's job was simply
8333 -- to make sure that its constituent expression was handled with checks
8334 -- off, and now that that is done, we can remove it from the tree, and
8335 -- indeed must, since gigi does not expect to see these nodes.
8337 procedure Expand_N_Unchecked_Expression
(N
: Node_Id
) is
8338 Exp
: constant Node_Id
:= Expression
(N
);
8341 Set_Assignment_OK
(Exp
, Assignment_OK
(N
) or Assignment_OK
(Exp
));
8343 end Expand_N_Unchecked_Expression
;
8345 ----------------------------------------
8346 -- Expand_N_Unchecked_Type_Conversion --
8347 ----------------------------------------
8349 -- If this cannot be handled by Gigi and we haven't already made a
8350 -- temporary for it, do it now.
8352 procedure Expand_N_Unchecked_Type_Conversion
(N
: Node_Id
) is
8353 Target_Type
: constant Entity_Id
:= Etype
(N
);
8354 Operand
: constant Node_Id
:= Expression
(N
);
8355 Operand_Type
: constant Entity_Id
:= Etype
(Operand
);
8358 -- If we have a conversion of a compile time known value to a target
8359 -- type and the value is in range of the target type, then we can simply
8360 -- replace the construct by an integer literal of the correct type. We
8361 -- only apply this to integer types being converted. Possibly it may
8362 -- apply in other cases, but it is too much trouble to worry about.
8364 -- Note that we do not do this transformation if the Kill_Range_Check
8365 -- flag is set, since then the value may be outside the expected range.
8366 -- This happens in the Normalize_Scalars case.
8368 -- We also skip this if either the target or operand type is biased
8369 -- because in this case, the unchecked conversion is supposed to
8370 -- preserve the bit pattern, not the integer value.
8372 if Is_Integer_Type
(Target_Type
)
8373 and then not Has_Biased_Representation
(Target_Type
)
8374 and then Is_Integer_Type
(Operand_Type
)
8375 and then not Has_Biased_Representation
(Operand_Type
)
8376 and then Compile_Time_Known_Value
(Operand
)
8377 and then not Kill_Range_Check
(N
)
8380 Val
: constant Uint
:= Expr_Value
(Operand
);
8383 if Compile_Time_Known_Value
(Type_Low_Bound
(Target_Type
))
8385 Compile_Time_Known_Value
(Type_High_Bound
(Target_Type
))
8387 Val
>= Expr_Value
(Type_Low_Bound
(Target_Type
))
8389 Val
<= Expr_Value
(Type_High_Bound
(Target_Type
))
8391 Rewrite
(N
, Make_Integer_Literal
(Sloc
(N
), Val
));
8393 -- If Address is the target type, just set the type to avoid a
8394 -- spurious type error on the literal when Address is a visible
8397 if Is_Descendent_Of_Address
(Target_Type
) then
8398 Set_Etype
(N
, Target_Type
);
8400 Analyze_And_Resolve
(N
, Target_Type
);
8408 -- Nothing to do if conversion is safe
8410 if Safe_Unchecked_Type_Conversion
(N
) then
8414 -- Otherwise force evaluation unless Assignment_OK flag is set (this
8415 -- flag indicates ??? -- more comments needed here)
8417 if Assignment_OK
(N
) then
8420 Force_Evaluation
(N
);
8422 end Expand_N_Unchecked_Type_Conversion
;
8424 ----------------------------
8425 -- Expand_Record_Equality --
8426 ----------------------------
8428 -- For non-variant records, Equality is expanded when needed into:
8430 -- and then Lhs.Discr1 = Rhs.Discr1
8432 -- and then Lhs.Discrn = Rhs.Discrn
8433 -- and then Lhs.Cmp1 = Rhs.Cmp1
8435 -- and then Lhs.Cmpn = Rhs.Cmpn
8437 -- The expression is folded by the back-end for adjacent fields. This
8438 -- function is called for tagged record in only one occasion: for imple-
8439 -- menting predefined primitive equality (see Predefined_Primitives_Bodies)
8440 -- otherwise the primitive "=" is used directly.
8442 function Expand_Record_Equality
8447 Bodies
: List_Id
) return Node_Id
8449 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
8454 First_Time
: Boolean := True;
8456 function Suitable_Element
(C
: Entity_Id
) return Entity_Id
;
8457 -- Return the first field to compare beginning with C, skipping the
8458 -- inherited components.
8460 ----------------------
8461 -- Suitable_Element --
8462 ----------------------
8464 function Suitable_Element
(C
: Entity_Id
) return Entity_Id
is
8469 elsif Ekind
(C
) /= E_Discriminant
8470 and then Ekind
(C
) /= E_Component
8472 return Suitable_Element
(Next_Entity
(C
));
8474 elsif Is_Tagged_Type
(Typ
)
8475 and then C
/= Original_Record_Component
(C
)
8477 return Suitable_Element
(Next_Entity
(C
));
8479 elsif Chars
(C
) = Name_uController
8480 or else Chars
(C
) = Name_uTag
8482 return Suitable_Element
(Next_Entity
(C
));
8484 elsif Is_Interface
(Etype
(C
)) then
8485 return Suitable_Element
(Next_Entity
(C
));
8490 end Suitable_Element
;
8492 -- Start of processing for Expand_Record_Equality
8495 -- Generates the following code: (assuming that Typ has one Discr and
8496 -- component C2 is also a record)
8499 -- and then Lhs.Discr1 = Rhs.Discr1
8500 -- and then Lhs.C1 = Rhs.C1
8501 -- and then Lhs.C2.C1=Rhs.C2.C1 and then ... Lhs.C2.Cn=Rhs.C2.Cn
8503 -- and then Lhs.Cmpn = Rhs.Cmpn
8505 Result
:= New_Reference_To
(Standard_True
, Loc
);
8506 C
:= Suitable_Element
(First_Entity
(Typ
));
8508 while Present
(C
) loop
8516 First_Time
:= False;
8520 New_Lhs
:= New_Copy_Tree
(Lhs
);
8521 New_Rhs
:= New_Copy_Tree
(Rhs
);
8525 Expand_Composite_Equality
(Nod
, Etype
(C
),
8527 Make_Selected_Component
(Loc
,
8529 Selector_Name
=> New_Reference_To
(C
, Loc
)),
8531 Make_Selected_Component
(Loc
,
8533 Selector_Name
=> New_Reference_To
(C
, Loc
)),
8536 -- If some (sub)component is an unchecked_union, the whole
8537 -- operation will raise program error.
8539 if Nkind
(Check
) = N_Raise_Program_Error
then
8541 Set_Etype
(Result
, Standard_Boolean
);
8546 Left_Opnd
=> Result
,
8547 Right_Opnd
=> Check
);
8551 C
:= Suitable_Element
(Next_Entity
(C
));
8555 end Expand_Record_Equality
;
8557 -------------------------------------
8558 -- Fixup_Universal_Fixed_Operation --
8559 -------------------------------------
8561 procedure Fixup_Universal_Fixed_Operation
(N
: Node_Id
) is
8562 Conv
: constant Node_Id
:= Parent
(N
);
8565 -- We must have a type conversion immediately above us
8567 pragma Assert
(Nkind
(Conv
) = N_Type_Conversion
);
8569 -- Normally the type conversion gives our target type. The exception
8570 -- occurs in the case of the Round attribute, where the conversion
8571 -- will be to universal real, and our real type comes from the Round
8572 -- attribute (as well as an indication that we must round the result)
8574 if Nkind
(Parent
(Conv
)) = N_Attribute_Reference
8575 and then Attribute_Name
(Parent
(Conv
)) = Name_Round
8577 Set_Etype
(N
, Etype
(Parent
(Conv
)));
8578 Set_Rounded_Result
(N
);
8580 -- Normal case where type comes from conversion above us
8583 Set_Etype
(N
, Etype
(Conv
));
8585 end Fixup_Universal_Fixed_Operation
;
8587 ------------------------------
8588 -- Get_Allocator_Final_List --
8589 ------------------------------
8591 function Get_Allocator_Final_List
8594 PtrT
: Entity_Id
) return Entity_Id
8596 Loc
: constant Source_Ptr
:= Sloc
(N
);
8598 Owner
: Entity_Id
:= PtrT
;
8599 -- The entity whose finalization list must be used to attach the
8600 -- allocated object.
8603 if Ekind
(PtrT
) = E_Anonymous_Access_Type
then
8605 -- If the context is an access parameter, we need to create a
8606 -- non-anonymous access type in order to have a usable final list,
8607 -- because there is otherwise no pool to which the allocated object
8608 -- can belong. We create both the type and the finalization chain
8609 -- here, because freezing an internal type does not create such a
8610 -- chain. The Final_Chain that is thus created is shared by the
8611 -- access parameter. The access type is tested against the result
8612 -- type of the function to exclude allocators whose type is an
8613 -- anonymous access result type. We freeze the type at once to
8614 -- ensure that it is properly decorated for the back-end, even
8615 -- if the context and current scope is a loop.
8617 if Nkind
(Associated_Node_For_Itype
(PtrT
))
8618 in N_Subprogram_Specification
8621 Etype
(Defining_Unit_Name
(Associated_Node_For_Itype
(PtrT
)))
8623 Owner
:= Make_Defining_Identifier
(Loc
, New_Internal_Name
('J'));
8625 Make_Full_Type_Declaration
(Loc
,
8626 Defining_Identifier
=> Owner
,
8628 Make_Access_To_Object_Definition
(Loc
,
8629 Subtype_Indication
=>
8630 New_Occurrence_Of
(T
, Loc
))));
8632 Freeze_Before
(N
, Owner
);
8633 Build_Final_List
(N
, Owner
);
8634 Set_Associated_Final_Chain
(PtrT
, Associated_Final_Chain
(Owner
));
8636 -- Ada 2005 (AI-318-02): If the context is a return object
8637 -- declaration, then the anonymous return subtype is defined to have
8638 -- the same accessibility level as that of the function's result
8639 -- subtype, which means that we want the scope where the function is
8642 elsif Nkind
(Associated_Node_For_Itype
(PtrT
)) = N_Object_Declaration
8643 and then Ekind
(Scope
(PtrT
)) = E_Return_Statement
8645 Owner
:= Scope
(Return_Applies_To
(Scope
(PtrT
)));
8647 -- Case of an access discriminant, or (Ada 2005), of an anonymous
8648 -- access component or anonymous access function result: find the
8649 -- final list associated with the scope of the type. (In the
8650 -- anonymous access component kind, a list controller will have
8651 -- been allocated when freezing the record type, and PtrT has an
8652 -- Associated_Final_Chain attribute designating it.)
8654 elsif No
(Associated_Final_Chain
(PtrT
)) then
8655 Owner
:= Scope
(PtrT
);
8659 return Find_Final_List
(Owner
);
8660 end Get_Allocator_Final_List
;
8662 ---------------------------------
8663 -- Has_Inferable_Discriminants --
8664 ---------------------------------
8666 function Has_Inferable_Discriminants
(N
: Node_Id
) return Boolean is
8668 function Prefix_Is_Formal_Parameter
(N
: Node_Id
) return Boolean;
8669 -- Determines whether the left-most prefix of a selected component is a
8670 -- formal parameter in a subprogram. Assumes N is a selected component.
8672 --------------------------------
8673 -- Prefix_Is_Formal_Parameter --
8674 --------------------------------
8676 function Prefix_Is_Formal_Parameter
(N
: Node_Id
) return Boolean is
8677 Sel_Comp
: Node_Id
:= N
;
8680 -- Move to the left-most prefix by climbing up the tree
8682 while Present
(Parent
(Sel_Comp
))
8683 and then Nkind
(Parent
(Sel_Comp
)) = N_Selected_Component
8685 Sel_Comp
:= Parent
(Sel_Comp
);
8688 return Ekind
(Entity
(Prefix
(Sel_Comp
))) in Formal_Kind
;
8689 end Prefix_Is_Formal_Parameter
;
8691 -- Start of processing for Has_Inferable_Discriminants
8694 -- For identifiers and indexed components, it is sufficient to have a
8695 -- constrained Unchecked_Union nominal subtype.
8697 if Nkind_In
(N
, N_Identifier
, N_Indexed_Component
) then
8698 return Is_Unchecked_Union
(Base_Type
(Etype
(N
)))
8700 Is_Constrained
(Etype
(N
));
8702 -- For selected components, the subtype of the selector must be a
8703 -- constrained Unchecked_Union. If the component is subject to a
8704 -- per-object constraint, then the enclosing object must have inferable
8707 elsif Nkind
(N
) = N_Selected_Component
then
8708 if Has_Per_Object_Constraint
(Entity
(Selector_Name
(N
))) then
8710 -- A small hack. If we have a per-object constrained selected
8711 -- component of a formal parameter, return True since we do not
8712 -- know the actual parameter association yet.
8714 if Prefix_Is_Formal_Parameter
(N
) then
8718 -- Otherwise, check the enclosing object and the selector
8720 return Has_Inferable_Discriminants
(Prefix
(N
))
8722 Has_Inferable_Discriminants
(Selector_Name
(N
));
8725 -- The call to Has_Inferable_Discriminants will determine whether
8726 -- the selector has a constrained Unchecked_Union nominal type.
8728 return Has_Inferable_Discriminants
(Selector_Name
(N
));
8730 -- A qualified expression has inferable discriminants if its subtype
8731 -- mark is a constrained Unchecked_Union subtype.
8733 elsif Nkind
(N
) = N_Qualified_Expression
then
8734 return Is_Unchecked_Union
(Subtype_Mark
(N
))
8736 Is_Constrained
(Subtype_Mark
(N
));
8741 end Has_Inferable_Discriminants
;
8743 -------------------------------
8744 -- Insert_Dereference_Action --
8745 -------------------------------
8747 procedure Insert_Dereference_Action
(N
: Node_Id
) is
8748 Loc
: constant Source_Ptr
:= Sloc
(N
);
8749 Typ
: constant Entity_Id
:= Etype
(N
);
8750 Pool
: constant Entity_Id
:= Associated_Storage_Pool
(Typ
);
8751 Pnod
: constant Node_Id
:= Parent
(N
);
8753 function Is_Checked_Storage_Pool
(P
: Entity_Id
) return Boolean;
8754 -- Return true if type of P is derived from Checked_Pool;
8756 -----------------------------
8757 -- Is_Checked_Storage_Pool --
8758 -----------------------------
8760 function Is_Checked_Storage_Pool
(P
: Entity_Id
) return Boolean is
8769 while T
/= Etype
(T
) loop
8770 if Is_RTE
(T
, RE_Checked_Pool
) then
8778 end Is_Checked_Storage_Pool
;
8780 -- Start of processing for Insert_Dereference_Action
8783 pragma Assert
(Nkind
(Pnod
) = N_Explicit_Dereference
);
8785 if not (Is_Checked_Storage_Pool
(Pool
)
8786 and then Comes_From_Source
(Original_Node
(Pnod
)))
8792 Make_Procedure_Call_Statement
(Loc
,
8793 Name
=> New_Reference_To
(
8794 Find_Prim_Op
(Etype
(Pool
), Name_Dereference
), Loc
),
8796 Parameter_Associations
=> New_List
(
8800 New_Reference_To
(Pool
, Loc
),
8802 -- Storage_Address. We use the attribute Pool_Address, which uses
8803 -- the pointer itself to find the address of the object, and which
8804 -- handles unconstrained arrays properly by computing the address
8805 -- of the template. i.e. the correct address of the corresponding
8808 Make_Attribute_Reference
(Loc
,
8809 Prefix
=> Duplicate_Subexpr_Move_Checks
(N
),
8810 Attribute_Name
=> Name_Pool_Address
),
8812 -- Size_In_Storage_Elements
8814 Make_Op_Divide
(Loc
,
8816 Make_Attribute_Reference
(Loc
,
8818 Make_Explicit_Dereference
(Loc
,
8819 Duplicate_Subexpr_Move_Checks
(N
)),
8820 Attribute_Name
=> Name_Size
),
8822 Make_Integer_Literal
(Loc
, System_Storage_Unit
)),
8826 Make_Attribute_Reference
(Loc
,
8828 Make_Explicit_Dereference
(Loc
,
8829 Duplicate_Subexpr_Move_Checks
(N
)),
8830 Attribute_Name
=> Name_Alignment
))));
8833 when RE_Not_Available
=>
8835 end Insert_Dereference_Action
;
8837 ------------------------------
8838 -- Make_Array_Comparison_Op --
8839 ------------------------------
8841 -- This is a hand-coded expansion of the following generic function:
8844 -- type elem is (<>);
8845 -- type index is (<>);
8846 -- type a is array (index range <>) of elem;
8848 -- function Gnnn (X : a; Y: a) return boolean is
8849 -- J : index := Y'first;
8852 -- if X'length = 0 then
8855 -- elsif Y'length = 0 then
8859 -- for I in X'range loop
8860 -- if X (I) = Y (J) then
8861 -- if J = Y'last then
8864 -- J := index'succ (J);
8868 -- return X (I) > Y (J);
8872 -- return X'length > Y'length;
8876 -- Note that since we are essentially doing this expansion by hand, we
8877 -- do not need to generate an actual or formal generic part, just the
8878 -- instantiated function itself.
8880 function Make_Array_Comparison_Op
8882 Nod
: Node_Id
) return Node_Id
8884 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
8886 X
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uX
);
8887 Y
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uY
);
8888 I
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uI
);
8889 J
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uJ
);
8891 Index
: constant Entity_Id
:= Base_Type
(Etype
(First_Index
(Typ
)));
8893 Loop_Statement
: Node_Id
;
8894 Loop_Body
: Node_Id
;
8897 Final_Expr
: Node_Id
;
8898 Func_Body
: Node_Id
;
8899 Func_Name
: Entity_Id
;
8905 -- if J = Y'last then
8908 -- J := index'succ (J);
8912 Make_Implicit_If_Statement
(Nod
,
8915 Left_Opnd
=> New_Reference_To
(J
, Loc
),
8917 Make_Attribute_Reference
(Loc
,
8918 Prefix
=> New_Reference_To
(Y
, Loc
),
8919 Attribute_Name
=> Name_Last
)),
8921 Then_Statements
=> New_List
(
8922 Make_Exit_Statement
(Loc
)),
8926 Make_Assignment_Statement
(Loc
,
8927 Name
=> New_Reference_To
(J
, Loc
),
8929 Make_Attribute_Reference
(Loc
,
8930 Prefix
=> New_Reference_To
(Index
, Loc
),
8931 Attribute_Name
=> Name_Succ
,
8932 Expressions
=> New_List
(New_Reference_To
(J
, Loc
))))));
8934 -- if X (I) = Y (J) then
8937 -- return X (I) > Y (J);
8941 Make_Implicit_If_Statement
(Nod
,
8945 Make_Indexed_Component
(Loc
,
8946 Prefix
=> New_Reference_To
(X
, Loc
),
8947 Expressions
=> New_List
(New_Reference_To
(I
, Loc
))),
8950 Make_Indexed_Component
(Loc
,
8951 Prefix
=> New_Reference_To
(Y
, Loc
),
8952 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)))),
8954 Then_Statements
=> New_List
(Inner_If
),
8956 Else_Statements
=> New_List
(
8957 Make_Simple_Return_Statement
(Loc
,
8961 Make_Indexed_Component
(Loc
,
8962 Prefix
=> New_Reference_To
(X
, Loc
),
8963 Expressions
=> New_List
(New_Reference_To
(I
, Loc
))),
8966 Make_Indexed_Component
(Loc
,
8967 Prefix
=> New_Reference_To
(Y
, Loc
),
8968 Expressions
=> New_List
(
8969 New_Reference_To
(J
, Loc
)))))));
8971 -- for I in X'range loop
8976 Make_Implicit_Loop_Statement
(Nod
,
8977 Identifier
=> Empty
,
8980 Make_Iteration_Scheme
(Loc
,
8981 Loop_Parameter_Specification
=>
8982 Make_Loop_Parameter_Specification
(Loc
,
8983 Defining_Identifier
=> I
,
8984 Discrete_Subtype_Definition
=>
8985 Make_Attribute_Reference
(Loc
,
8986 Prefix
=> New_Reference_To
(X
, Loc
),
8987 Attribute_Name
=> Name_Range
))),
8989 Statements
=> New_List
(Loop_Body
));
8991 -- if X'length = 0 then
8993 -- elsif Y'length = 0 then
8996 -- for ... loop ... end loop;
8997 -- return X'length > Y'length;
9001 Make_Attribute_Reference
(Loc
,
9002 Prefix
=> New_Reference_To
(X
, Loc
),
9003 Attribute_Name
=> Name_Length
);
9006 Make_Attribute_Reference
(Loc
,
9007 Prefix
=> New_Reference_To
(Y
, Loc
),
9008 Attribute_Name
=> Name_Length
);
9012 Left_Opnd
=> Length1
,
9013 Right_Opnd
=> Length2
);
9016 Make_Implicit_If_Statement
(Nod
,
9020 Make_Attribute_Reference
(Loc
,
9021 Prefix
=> New_Reference_To
(X
, Loc
),
9022 Attribute_Name
=> Name_Length
),
9024 Make_Integer_Literal
(Loc
, 0)),
9028 Make_Simple_Return_Statement
(Loc
,
9029 Expression
=> New_Reference_To
(Standard_False
, Loc
))),
9031 Elsif_Parts
=> New_List
(
9032 Make_Elsif_Part
(Loc
,
9036 Make_Attribute_Reference
(Loc
,
9037 Prefix
=> New_Reference_To
(Y
, Loc
),
9038 Attribute_Name
=> Name_Length
),
9040 Make_Integer_Literal
(Loc
, 0)),
9044 Make_Simple_Return_Statement
(Loc
,
9045 Expression
=> New_Reference_To
(Standard_True
, Loc
))))),
9047 Else_Statements
=> New_List
(
9049 Make_Simple_Return_Statement
(Loc
,
9050 Expression
=> Final_Expr
)));
9054 Formals
:= New_List
(
9055 Make_Parameter_Specification
(Loc
,
9056 Defining_Identifier
=> X
,
9057 Parameter_Type
=> New_Reference_To
(Typ
, Loc
)),
9059 Make_Parameter_Specification
(Loc
,
9060 Defining_Identifier
=> Y
,
9061 Parameter_Type
=> New_Reference_To
(Typ
, Loc
)));
9063 -- function Gnnn (...) return boolean is
9064 -- J : index := Y'first;
9069 Func_Name
:= Make_Defining_Identifier
(Loc
, New_Internal_Name
('G'));
9072 Make_Subprogram_Body
(Loc
,
9074 Make_Function_Specification
(Loc
,
9075 Defining_Unit_Name
=> Func_Name
,
9076 Parameter_Specifications
=> Formals
,
9077 Result_Definition
=> New_Reference_To
(Standard_Boolean
, Loc
)),
9079 Declarations
=> New_List
(
9080 Make_Object_Declaration
(Loc
,
9081 Defining_Identifier
=> J
,
9082 Object_Definition
=> New_Reference_To
(Index
, Loc
),
9084 Make_Attribute_Reference
(Loc
,
9085 Prefix
=> New_Reference_To
(Y
, Loc
),
9086 Attribute_Name
=> Name_First
))),
9088 Handled_Statement_Sequence
=>
9089 Make_Handled_Sequence_Of_Statements
(Loc
,
9090 Statements
=> New_List
(If_Stat
)));
9093 end Make_Array_Comparison_Op
;
9095 ---------------------------
9096 -- Make_Boolean_Array_Op --
9097 ---------------------------
9099 -- For logical operations on boolean arrays, expand in line the following,
9100 -- replacing 'and' with 'or' or 'xor' where needed:
9102 -- function Annn (A : typ; B: typ) return typ is
9105 -- for J in A'range loop
9106 -- C (J) := A (J) op B (J);
9111 -- Here typ is the boolean array type
9113 function Make_Boolean_Array_Op
9115 N
: Node_Id
) return Node_Id
9117 Loc
: constant Source_Ptr
:= Sloc
(N
);
9119 A
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uA
);
9120 B
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uB
);
9121 C
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uC
);
9122 J
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uJ
);
9130 Func_Name
: Entity_Id
;
9131 Func_Body
: Node_Id
;
9132 Loop_Statement
: Node_Id
;
9136 Make_Indexed_Component
(Loc
,
9137 Prefix
=> New_Reference_To
(A
, Loc
),
9138 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)));
9141 Make_Indexed_Component
(Loc
,
9142 Prefix
=> New_Reference_To
(B
, Loc
),
9143 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)));
9146 Make_Indexed_Component
(Loc
,
9147 Prefix
=> New_Reference_To
(C
, Loc
),
9148 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)));
9150 if Nkind
(N
) = N_Op_And
then
9156 elsif Nkind
(N
) = N_Op_Or
then
9170 Make_Implicit_Loop_Statement
(N
,
9171 Identifier
=> Empty
,
9174 Make_Iteration_Scheme
(Loc
,
9175 Loop_Parameter_Specification
=>
9176 Make_Loop_Parameter_Specification
(Loc
,
9177 Defining_Identifier
=> J
,
9178 Discrete_Subtype_Definition
=>
9179 Make_Attribute_Reference
(Loc
,
9180 Prefix
=> New_Reference_To
(A
, Loc
),
9181 Attribute_Name
=> Name_Range
))),
9183 Statements
=> New_List
(
9184 Make_Assignment_Statement
(Loc
,
9186 Expression
=> Op
)));
9188 Formals
:= New_List
(
9189 Make_Parameter_Specification
(Loc
,
9190 Defining_Identifier
=> A
,
9191 Parameter_Type
=> New_Reference_To
(Typ
, Loc
)),
9193 Make_Parameter_Specification
(Loc
,
9194 Defining_Identifier
=> B
,
9195 Parameter_Type
=> New_Reference_To
(Typ
, Loc
)));
9198 Make_Defining_Identifier
(Loc
, New_Internal_Name
('A'));
9199 Set_Is_Inlined
(Func_Name
);
9202 Make_Subprogram_Body
(Loc
,
9204 Make_Function_Specification
(Loc
,
9205 Defining_Unit_Name
=> Func_Name
,
9206 Parameter_Specifications
=> Formals
,
9207 Result_Definition
=> New_Reference_To
(Typ
, Loc
)),
9209 Declarations
=> New_List
(
9210 Make_Object_Declaration
(Loc
,
9211 Defining_Identifier
=> C
,
9212 Object_Definition
=> New_Reference_To
(Typ
, Loc
))),
9214 Handled_Statement_Sequence
=>
9215 Make_Handled_Sequence_Of_Statements
(Loc
,
9216 Statements
=> New_List
(
9218 Make_Simple_Return_Statement
(Loc
,
9219 Expression
=> New_Reference_To
(C
, Loc
)))));
9222 end Make_Boolean_Array_Op
;
9224 ------------------------
9225 -- Rewrite_Comparison --
9226 ------------------------
9228 procedure Rewrite_Comparison
(N
: Node_Id
) is
9229 Warning_Generated
: Boolean := False;
9230 -- Set to True if first pass with Assume_Valid generates a warning in
9231 -- which case we skip the second pass to avoid warning overloaded.
9234 -- Set to Standard_True or Standard_False
9237 if Nkind
(N
) = N_Type_Conversion
then
9238 Rewrite_Comparison
(Expression
(N
));
9241 elsif Nkind
(N
) not in N_Op_Compare
then
9245 -- Now start looking at the comparison in detail. We potentially go
9246 -- through this loop twice. The first time, Assume_Valid is set False
9247 -- in the call to Compile_Time_Compare. If this call results in a
9248 -- clear result of always True or Always False, that's decisive and
9249 -- we are done. Otherwise we repeat the processing with Assume_Valid
9250 -- set to True to generate additional warnings. We can stil that step
9251 -- if Constant_Condition_Warnings is False.
9253 for AV
in False .. True loop
9255 Typ
: constant Entity_Id
:= Etype
(N
);
9256 Op1
: constant Node_Id
:= Left_Opnd
(N
);
9257 Op2
: constant Node_Id
:= Right_Opnd
(N
);
9259 Res
: constant Compare_Result
:=
9260 Compile_Time_Compare
(Op1
, Op2
, Assume_Valid
=> AV
);
9261 -- Res indicates if compare outcome can be compile time determined
9263 True_Result
: Boolean;
9264 False_Result
: Boolean;
9267 case N_Op_Compare
(Nkind
(N
)) is
9269 True_Result
:= Res
= EQ
;
9270 False_Result
:= Res
= LT
or else Res
= GT
or else Res
= NE
;
9273 True_Result
:= Res
in Compare_GE
;
9274 False_Result
:= Res
= LT
;
9277 and then Constant_Condition_Warnings
9278 and then Comes_From_Source
(Original_Node
(N
))
9279 and then Nkind
(Original_Node
(N
)) = N_Op_Ge
9280 and then not In_Instance
9281 and then Is_Integer_Type
(Etype
(Left_Opnd
(N
)))
9282 and then not Has_Warnings_Off
(Etype
(Left_Opnd
(N
)))
9285 ("can never be greater than, could replace by ""'=""?", N
);
9286 Warning_Generated
:= True;
9290 True_Result
:= Res
= GT
;
9291 False_Result
:= Res
in Compare_LE
;
9294 True_Result
:= Res
= LT
;
9295 False_Result
:= Res
in Compare_GE
;
9298 True_Result
:= Res
in Compare_LE
;
9299 False_Result
:= Res
= GT
;
9302 and then Constant_Condition_Warnings
9303 and then Comes_From_Source
(Original_Node
(N
))
9304 and then Nkind
(Original_Node
(N
)) = N_Op_Le
9305 and then not In_Instance
9306 and then Is_Integer_Type
(Etype
(Left_Opnd
(N
)))
9307 and then not Has_Warnings_Off
(Etype
(Left_Opnd
(N
)))
9310 ("can never be less than, could replace by ""'=""?", N
);
9311 Warning_Generated
:= True;
9315 True_Result
:= Res
= NE
or else Res
= GT
or else Res
= LT
;
9316 False_Result
:= Res
= EQ
;
9319 -- If this is the first iteration, then we actually convert the
9320 -- comparison into True or False, if the result is certain.
9323 if True_Result
or False_Result
then
9325 Result
:= Standard_True
;
9327 Result
:= Standard_False
;
9332 New_Occurrence_Of
(Result
, Sloc
(N
))));
9333 Analyze_And_Resolve
(N
, Typ
);
9334 Warn_On_Known_Condition
(N
);
9338 -- If this is the second iteration (AV = True), and the original
9339 -- node comes from source and we are not in an instance, then
9340 -- give a warning if we know result would be True or False. Note
9341 -- we know Constant_Condition_Warnings is set if we get here.
9343 elsif Comes_From_Source
(Original_Node
(N
))
9344 and then not In_Instance
9348 ("condition can only be False if invalid values present?",
9350 elsif False_Result
then
9352 ("condition can only be True if invalid values present?",
9358 -- Skip second iteration if not warning on constant conditions or
9359 -- if the first iteration already generated a warning of some kind
9360 -- or if we are in any case assuming all values are valid (so that
9361 -- the first iteration took care of the valid case).
9363 exit when not Constant_Condition_Warnings
;
9364 exit when Warning_Generated
;
9365 exit when Assume_No_Invalid_Values
;
9367 end Rewrite_Comparison
;
9369 ----------------------------
9370 -- Safe_In_Place_Array_Op --
9371 ----------------------------
9373 function Safe_In_Place_Array_Op
9376 Op2
: Node_Id
) return Boolean
9380 function Is_Safe_Operand
(Op
: Node_Id
) return Boolean;
9381 -- Operand is safe if it cannot overlap part of the target of the
9382 -- operation. If the operand and the target are identical, the operand
9383 -- is safe. The operand can be empty in the case of negation.
9385 function Is_Unaliased
(N
: Node_Id
) return Boolean;
9386 -- Check that N is a stand-alone entity
9392 function Is_Unaliased
(N
: Node_Id
) return Boolean is
9396 and then No
(Address_Clause
(Entity
(N
)))
9397 and then No
(Renamed_Object
(Entity
(N
)));
9400 ---------------------
9401 -- Is_Safe_Operand --
9402 ---------------------
9404 function Is_Safe_Operand
(Op
: Node_Id
) return Boolean is
9409 elsif Is_Entity_Name
(Op
) then
9410 return Is_Unaliased
(Op
);
9412 elsif Nkind_In
(Op
, N_Indexed_Component
, N_Selected_Component
) then
9413 return Is_Unaliased
(Prefix
(Op
));
9415 elsif Nkind
(Op
) = N_Slice
then
9417 Is_Unaliased
(Prefix
(Op
))
9418 and then Entity
(Prefix
(Op
)) /= Target
;
9420 elsif Nkind
(Op
) = N_Op_Not
then
9421 return Is_Safe_Operand
(Right_Opnd
(Op
));
9426 end Is_Safe_Operand
;
9428 -- Start of processing for Is_Safe_In_Place_Array_Op
9431 -- Skip this processing if the component size is different from system
9432 -- storage unit (since at least for NOT this would cause problems).
9434 if Component_Size
(Etype
(Lhs
)) /= System_Storage_Unit
then
9437 -- Cannot do in place stuff on VM_Target since cannot pass addresses
9439 elsif VM_Target
/= No_VM
then
9442 -- Cannot do in place stuff if non-standard Boolean representation
9444 elsif Has_Non_Standard_Rep
(Component_Type
(Etype
(Lhs
))) then
9447 elsif not Is_Unaliased
(Lhs
) then
9450 Target
:= Entity
(Lhs
);
9453 Is_Safe_Operand
(Op1
)
9454 and then Is_Safe_Operand
(Op2
);
9456 end Safe_In_Place_Array_Op
;
9458 -----------------------
9459 -- Tagged_Membership --
9460 -----------------------
9462 -- There are two different cases to consider depending on whether the right
9463 -- operand is a class-wide type or not. If not we just compare the actual
9464 -- tag of the left expr to the target type tag:
9466 -- Left_Expr.Tag = Right_Type'Tag;
9468 -- If it is a class-wide type we use the RT function CW_Membership which is
9469 -- usually implemented by looking in the ancestor tables contained in the
9470 -- dispatch table pointed by Left_Expr.Tag for Typ'Tag
9472 -- Ada 2005 (AI-251): If it is a class-wide interface type we use the RT
9473 -- function IW_Membership which is usually implemented by looking in the
9474 -- table of abstract interface types plus the ancestor table contained in
9475 -- the dispatch table pointed by Left_Expr.Tag for Typ'Tag
9477 function Tagged_Membership
(N
: Node_Id
) return Node_Id
is
9478 Left
: constant Node_Id
:= Left_Opnd
(N
);
9479 Right
: constant Node_Id
:= Right_Opnd
(N
);
9480 Loc
: constant Source_Ptr
:= Sloc
(N
);
9482 Left_Type
: Entity_Id
;
9483 Right_Type
: Entity_Id
;
9487 Left_Type
:= Etype
(Left
);
9488 Right_Type
:= Etype
(Right
);
9490 if Is_Class_Wide_Type
(Left_Type
) then
9491 Left_Type
:= Root_Type
(Left_Type
);
9495 Make_Selected_Component
(Loc
,
9496 Prefix
=> Relocate_Node
(Left
),
9498 New_Reference_To
(First_Tag_Component
(Left_Type
), Loc
));
9500 if Is_Class_Wide_Type
(Right_Type
) then
9502 -- No need to issue a run-time check if we statically know that the
9503 -- result of this membership test is always true. For example,
9504 -- considering the following declarations:
9506 -- type Iface is interface;
9507 -- type T is tagged null record;
9508 -- type DT is new T and Iface with null record;
9513 -- These membership tests are always true:
9517 -- Obj2 in Iface'Class;
9519 -- We do not need to handle cases where the membership is illegal.
9522 -- Obj1 in DT'Class; -- Compile time error
9523 -- Obj1 in Iface'Class; -- Compile time error
9525 if not Is_Class_Wide_Type
(Left_Type
)
9526 and then (Is_Ancestor
(Etype
(Right_Type
), Left_Type
)
9527 or else (Is_Interface
(Etype
(Right_Type
))
9528 and then Interface_Present_In_Ancestor
9530 Iface
=> Etype
(Right_Type
))))
9532 return New_Reference_To
(Standard_True
, Loc
);
9535 -- Ada 2005 (AI-251): Class-wide applied to interfaces
9537 if Is_Interface
(Etype
(Class_Wide_Type
(Right_Type
)))
9539 -- Support to: "Iface_CW_Typ in Typ'Class"
9541 or else Is_Interface
(Left_Type
)
9543 -- Issue error if IW_Membership operation not available in a
9544 -- configurable run time setting.
9546 if not RTE_Available
(RE_IW_Membership
) then
9548 ("dynamic membership test on interface types", N
);
9553 Make_Function_Call
(Loc
,
9554 Name
=> New_Occurrence_Of
(RTE
(RE_IW_Membership
), Loc
),
9555 Parameter_Associations
=> New_List
(
9556 Make_Attribute_Reference
(Loc
,
9558 Attribute_Name
=> Name_Address
),
9561 (Access_Disp_Table
(Root_Type
(Right_Type
)))),
9564 -- Ada 95: Normal case
9568 Build_CW_Membership
(Loc
,
9569 Obj_Tag_Node
=> Obj_Tag
,
9573 (Access_Disp_Table
(Root_Type
(Right_Type
)))),
9577 -- Right_Type is not a class-wide type
9580 -- No need to check the tag of the object if Right_Typ is abstract
9582 if Is_Abstract_Type
(Right_Type
) then
9583 return New_Reference_To
(Standard_False
, Loc
);
9588 Left_Opnd
=> Obj_Tag
,
9591 (Node
(First_Elmt
(Access_Disp_Table
(Right_Type
))), Loc
));
9594 end Tagged_Membership
;
9596 ------------------------------
9597 -- Unary_Op_Validity_Checks --
9598 ------------------------------
9600 procedure Unary_Op_Validity_Checks
(N
: Node_Id
) is
9602 if Validity_Checks_On
and Validity_Check_Operands
then
9603 Ensure_Valid
(Right_Opnd
(N
));
9605 end Unary_Op_Validity_Checks
;