1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, 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 Par_SCO
; use Par_SCO
;
51 with Restrict
; use Restrict
;
52 with Rident
; use Rident
;
53 with Rtsfind
; use Rtsfind
;
55 with Sem_Aux
; use Sem_Aux
;
56 with Sem_Cat
; use Sem_Cat
;
57 with Sem_Ch3
; use Sem_Ch3
;
58 with Sem_Ch8
; use Sem_Ch8
;
59 with Sem_Ch13
; use Sem_Ch13
;
60 with Sem_Eval
; use Sem_Eval
;
61 with Sem_Res
; use Sem_Res
;
62 with Sem_Type
; use Sem_Type
;
63 with Sem_Util
; use Sem_Util
;
64 with Sem_Warn
; use Sem_Warn
;
65 with Sinfo
; use Sinfo
;
66 with Snames
; use Snames
;
67 with Stand
; use Stand
;
68 with SCIL_LL
; use SCIL_LL
;
69 with Targparm
; use Targparm
;
70 with Tbuild
; use Tbuild
;
71 with Ttypes
; use Ttypes
;
72 with Uintp
; use Uintp
;
73 with Urealp
; use Urealp
;
74 with Validsw
; use Validsw
;
76 package body Exp_Ch4
is
78 -----------------------
79 -- Local Subprograms --
80 -----------------------
82 procedure Binary_Op_Validity_Checks
(N
: Node_Id
);
83 pragma Inline
(Binary_Op_Validity_Checks
);
84 -- Performs validity checks for a binary operator
86 procedure Build_Boolean_Array_Proc_Call
90 -- If a boolean array assignment can be done in place, build call to
91 -- corresponding library procedure.
93 procedure Displace_Allocator_Pointer
(N
: Node_Id
);
94 -- Ada 2005 (AI-251): Subsidiary procedure to Expand_N_Allocator and
95 -- Expand_Allocator_Expression. Allocating class-wide interface objects
96 -- this routine displaces the pointer to the allocated object to reference
97 -- the component referencing the corresponding secondary dispatch table.
99 procedure Expand_Allocator_Expression
(N
: Node_Id
);
100 -- Subsidiary to Expand_N_Allocator, for the case when the expression
101 -- is a qualified expression or an aggregate.
103 procedure Expand_Array_Comparison
(N
: Node_Id
);
104 -- This routine handles expansion of the comparison operators (N_Op_Lt,
105 -- N_Op_Le, N_Op_Gt, N_Op_Ge) when operating on an array type. The basic
106 -- code for these operators is similar, differing only in the details of
107 -- the actual comparison call that is made. Special processing (call a
110 function Expand_Array_Equality
115 Typ
: Entity_Id
) return Node_Id
;
116 -- Expand an array equality into a call to a function implementing this
117 -- equality, and a call to it. Loc is the location for the generated nodes.
118 -- Lhs and Rhs are the array expressions to be compared. Bodies is a list
119 -- on which to attach bodies of local functions that are created in the
120 -- process. It is the responsibility of the caller to insert those bodies
121 -- at the right place. Nod provides the Sloc value for the generated code.
122 -- Normally the types used for the generated equality routine are taken
123 -- from Lhs and Rhs. However, in some situations of generated code, the
124 -- Etype fields of Lhs and Rhs are not set yet. In such cases, Typ supplies
125 -- the type to be used for the formal parameters.
127 procedure Expand_Boolean_Operator
(N
: Node_Id
);
128 -- Common expansion processing for Boolean operators (And, Or, Xor) for the
129 -- case of array type arguments.
131 procedure Expand_Short_Circuit_Operator
(N
: Node_Id
);
132 -- Common expansion processing for short-circuit boolean operators
134 function Expand_Composite_Equality
139 Bodies
: List_Id
) return Node_Id
;
140 -- Local recursive function used to expand equality for nested composite
141 -- types. Used by Expand_Record/Array_Equality, Bodies is a list on which
142 -- to attach bodies of local functions that are created in the process.
143 -- This is the responsibility of the caller to insert those bodies at the
144 -- right place. Nod provides the Sloc value for generated code. Lhs and Rhs
145 -- are the left and right sides for the comparison, and Typ is the type of
146 -- the arrays to compare.
148 procedure Expand_Concatenate
(Cnode
: Node_Id
; Opnds
: List_Id
);
149 -- Routine to expand concatenation of a sequence of two or more operands
150 -- (in the list Operands) and replace node Cnode with the result of the
151 -- concatenation. The operands can be of any appropriate type, and can
152 -- include both arrays and singleton elements.
154 procedure Fixup_Universal_Fixed_Operation
(N
: Node_Id
);
155 -- N is a N_Op_Divide or N_Op_Multiply node whose result is universal
156 -- fixed. We do not have such a type at runtime, so the purpose of this
157 -- routine is to find the real type by looking up the tree. We also
158 -- determine if the operation must be rounded.
160 function Get_Allocator_Final_List
163 PtrT
: Entity_Id
) return Entity_Id
;
164 -- If the designated type is controlled, build final_list expression for
165 -- created object. If context is an access parameter, create a local access
166 -- type to have a usable finalization list.
168 function Has_Inferable_Discriminants
(N
: Node_Id
) return Boolean;
169 -- Ada 2005 (AI-216): A view of an Unchecked_Union object has inferable
170 -- discriminants if it has a constrained nominal type, unless the object
171 -- is a component of an enclosing Unchecked_Union object that is subject
172 -- to a per-object constraint and the enclosing object lacks inferable
175 -- An expression of an Unchecked_Union type has inferable discriminants
176 -- if it is either a name of an object with inferable discriminants or a
177 -- qualified expression whose subtype mark denotes a constrained subtype.
179 procedure Insert_Dereference_Action
(N
: Node_Id
);
180 -- N is an expression whose type is an access. When the type of the
181 -- associated storage pool is derived from Checked_Pool, generate a
182 -- call to the 'Dereference' primitive operation.
184 function Make_Array_Comparison_Op
186 Nod
: Node_Id
) return Node_Id
;
187 -- Comparisons between arrays are expanded in line. This function produces
188 -- the body of the implementation of (a > b), where a and b are one-
189 -- dimensional arrays of some discrete type. The original node is then
190 -- expanded into the appropriate call to this function. Nod provides the
191 -- Sloc value for the generated code.
193 function Make_Boolean_Array_Op
195 N
: Node_Id
) return Node_Id
;
196 -- Boolean operations on boolean arrays are expanded in line. This function
197 -- produce the body for the node N, which is (a and b), (a or b), or (a xor
198 -- b). It is used only the normal case and not the packed case. The type
199 -- involved, Typ, is the Boolean array type, and the logical operations in
200 -- the body are simple boolean operations. Note that Typ is always a
201 -- constrained type (the caller has ensured this by using
202 -- Convert_To_Actual_Subtype if necessary).
204 procedure Rewrite_Comparison
(N
: Node_Id
);
205 -- If N is the node for a comparison whose outcome can be determined at
206 -- compile time, then the node N can be rewritten with True or False. If
207 -- the outcome cannot be determined at compile time, the call has no
208 -- effect. If N is a type conversion, then this processing is applied to
209 -- its expression. If N is neither comparison nor a type conversion, the
210 -- call has no effect.
212 procedure Tagged_Membership
214 SCIL_Node
: out Node_Id
;
215 Result
: out Node_Id
);
216 -- Construct the expression corresponding to the tagged membership test.
217 -- Deals with a second operand being (or not) a class-wide type.
219 function Safe_In_Place_Array_Op
222 Op2
: Node_Id
) return Boolean;
223 -- In the context of an assignment, where the right-hand side is a boolean
224 -- operation on arrays, check whether operation can be performed in place.
226 procedure Unary_Op_Validity_Checks
(N
: Node_Id
);
227 pragma Inline
(Unary_Op_Validity_Checks
);
228 -- Performs validity checks for a unary operator
230 -------------------------------
231 -- Binary_Op_Validity_Checks --
232 -------------------------------
234 procedure Binary_Op_Validity_Checks
(N
: Node_Id
) is
236 if Validity_Checks_On
and Validity_Check_Operands
then
237 Ensure_Valid
(Left_Opnd
(N
));
238 Ensure_Valid
(Right_Opnd
(N
));
240 end Binary_Op_Validity_Checks
;
242 ------------------------------------
243 -- Build_Boolean_Array_Proc_Call --
244 ------------------------------------
246 procedure Build_Boolean_Array_Proc_Call
251 Loc
: constant Source_Ptr
:= Sloc
(N
);
252 Kind
: constant Node_Kind
:= Nkind
(Expression
(N
));
253 Target
: constant Node_Id
:=
254 Make_Attribute_Reference
(Loc
,
256 Attribute_Name
=> Name_Address
);
258 Arg1
: constant Node_Id
:= Op1
;
259 Arg2
: Node_Id
:= Op2
;
261 Proc_Name
: Entity_Id
;
264 if Kind
= N_Op_Not
then
265 if Nkind
(Op1
) in N_Binary_Op
then
267 -- Use negated version of the binary operators
269 if Nkind
(Op1
) = N_Op_And
then
270 Proc_Name
:= RTE
(RE_Vector_Nand
);
272 elsif Nkind
(Op1
) = N_Op_Or
then
273 Proc_Name
:= RTE
(RE_Vector_Nor
);
275 else pragma Assert
(Nkind
(Op1
) = N_Op_Xor
);
276 Proc_Name
:= RTE
(RE_Vector_Xor
);
280 Make_Procedure_Call_Statement
(Loc
,
281 Name
=> New_Occurrence_Of
(Proc_Name
, Loc
),
283 Parameter_Associations
=> New_List
(
285 Make_Attribute_Reference
(Loc
,
286 Prefix
=> Left_Opnd
(Op1
),
287 Attribute_Name
=> Name_Address
),
289 Make_Attribute_Reference
(Loc
,
290 Prefix
=> Right_Opnd
(Op1
),
291 Attribute_Name
=> Name_Address
),
293 Make_Attribute_Reference
(Loc
,
294 Prefix
=> Left_Opnd
(Op1
),
295 Attribute_Name
=> Name_Length
)));
298 Proc_Name
:= RTE
(RE_Vector_Not
);
301 Make_Procedure_Call_Statement
(Loc
,
302 Name
=> New_Occurrence_Of
(Proc_Name
, Loc
),
303 Parameter_Associations
=> New_List
(
306 Make_Attribute_Reference
(Loc
,
308 Attribute_Name
=> Name_Address
),
310 Make_Attribute_Reference
(Loc
,
312 Attribute_Name
=> Name_Length
)));
316 -- We use the following equivalences:
318 -- (not X) or (not Y) = not (X and Y) = Nand (X, Y)
319 -- (not X) and (not Y) = not (X or Y) = Nor (X, Y)
320 -- (not X) xor (not Y) = X xor Y
321 -- X xor (not Y) = not (X xor Y) = Nxor (X, Y)
323 if Nkind
(Op1
) = N_Op_Not
then
324 if Kind
= N_Op_And
then
325 Proc_Name
:= RTE
(RE_Vector_Nor
);
326 elsif Kind
= N_Op_Or
then
327 Proc_Name
:= RTE
(RE_Vector_Nand
);
329 Proc_Name
:= RTE
(RE_Vector_Xor
);
333 if Kind
= N_Op_And
then
334 Proc_Name
:= RTE
(RE_Vector_And
);
335 elsif Kind
= N_Op_Or
then
336 Proc_Name
:= RTE
(RE_Vector_Or
);
337 elsif Nkind
(Op2
) = N_Op_Not
then
338 Proc_Name
:= RTE
(RE_Vector_Nxor
);
339 Arg2
:= Right_Opnd
(Op2
);
341 Proc_Name
:= RTE
(RE_Vector_Xor
);
346 Make_Procedure_Call_Statement
(Loc
,
347 Name
=> New_Occurrence_Of
(Proc_Name
, Loc
),
348 Parameter_Associations
=> New_List
(
350 Make_Attribute_Reference
(Loc
,
352 Attribute_Name
=> Name_Address
),
353 Make_Attribute_Reference
(Loc
,
355 Attribute_Name
=> Name_Address
),
356 Make_Attribute_Reference
(Loc
,
358 Attribute_Name
=> Name_Length
)));
361 Rewrite
(N
, Call_Node
);
365 when RE_Not_Available
=>
367 end Build_Boolean_Array_Proc_Call
;
369 --------------------------------
370 -- Displace_Allocator_Pointer --
371 --------------------------------
373 procedure Displace_Allocator_Pointer
(N
: Node_Id
) is
374 Loc
: constant Source_Ptr
:= Sloc
(N
);
375 Orig_Node
: constant Node_Id
:= Original_Node
(N
);
381 -- Do nothing in case of VM targets: the virtual machine will handle
382 -- interfaces directly.
384 if not Tagged_Type_Expansion
then
388 pragma Assert
(Nkind
(N
) = N_Identifier
389 and then Nkind
(Orig_Node
) = N_Allocator
);
391 PtrT
:= Etype
(Orig_Node
);
392 Dtyp
:= Available_View
(Designated_Type
(PtrT
));
393 Etyp
:= Etype
(Expression
(Orig_Node
));
395 if Is_Class_Wide_Type
(Dtyp
)
396 and then Is_Interface
(Dtyp
)
398 -- If the type of the allocator expression is not an interface type
399 -- we can generate code to reference the record component containing
400 -- the pointer to the secondary dispatch table.
402 if not Is_Interface
(Etyp
) then
404 Saved_Typ
: constant Entity_Id
:= Etype
(Orig_Node
);
407 -- 1) Get access to the allocated object
410 Make_Explicit_Dereference
(Loc
,
415 -- 2) Add the conversion to displace the pointer to reference
416 -- the secondary dispatch table.
418 Rewrite
(N
, Convert_To
(Dtyp
, Relocate_Node
(N
)));
419 Analyze_And_Resolve
(N
, Dtyp
);
421 -- 3) The 'access to the secondary dispatch table will be used
422 -- as the value returned by the allocator.
425 Make_Attribute_Reference
(Loc
,
426 Prefix
=> Relocate_Node
(N
),
427 Attribute_Name
=> Name_Access
));
428 Set_Etype
(N
, Saved_Typ
);
432 -- If the type of the allocator expression is an interface type we
433 -- generate a run-time call to displace "this" to reference the
434 -- component containing the pointer to the secondary dispatch table
435 -- or else raise Constraint_Error if the actual object does not
436 -- implement the target interface. This case corresponds with the
437 -- following example:
439 -- function Op (Obj : Iface_1'Class) return access Iface_2'Class is
441 -- return new Iface_2'Class'(Obj);
446 Unchecked_Convert_To
(PtrT
,
447 Make_Function_Call
(Loc
,
448 Name
=> New_Reference_To
(RTE
(RE_Displace
), Loc
),
449 Parameter_Associations
=> New_List
(
450 Unchecked_Convert_To
(RTE
(RE_Address
),
456 (Access_Disp_Table
(Etype
(Base_Type
(Dtyp
))))),
458 Analyze_And_Resolve
(N
, PtrT
);
461 end Displace_Allocator_Pointer
;
463 ---------------------------------
464 -- Expand_Allocator_Expression --
465 ---------------------------------
467 procedure Expand_Allocator_Expression
(N
: Node_Id
) is
468 Loc
: constant Source_Ptr
:= Sloc
(N
);
469 Exp
: constant Node_Id
:= Expression
(Expression
(N
));
470 PtrT
: constant Entity_Id
:= Etype
(N
);
471 DesigT
: constant Entity_Id
:= Designated_Type
(PtrT
);
473 procedure Apply_Accessibility_Check
475 Built_In_Place
: Boolean := False);
476 -- Ada 2005 (AI-344): For an allocator with a class-wide designated
477 -- type, generate an accessibility check to verify that the level of the
478 -- type of the created object is not deeper than the level of the access
479 -- type. If the type of the qualified expression is class- wide, then
480 -- always generate the check (except in the case where it is known to be
481 -- unnecessary, see comment below). Otherwise, only generate the check
482 -- if the level of the qualified expression type is statically deeper
483 -- than the access type.
485 -- Although the static accessibility will generally have been performed
486 -- as a legality check, it won't have been done in cases where the
487 -- allocator appears in generic body, so a run-time check is needed in
488 -- general. One special case is when the access type is declared in the
489 -- same scope as the class-wide allocator, in which case the check can
490 -- never fail, so it need not be generated.
492 -- As an open issue, there seem to be cases where the static level
493 -- associated with the class-wide object's underlying type is not
494 -- sufficient to perform the proper accessibility check, such as for
495 -- allocators in nested subprograms or accept statements initialized by
496 -- class-wide formals when the actual originates outside at a deeper
497 -- static level. The nested subprogram case might require passing
498 -- accessibility levels along with class-wide parameters, and the task
499 -- case seems to be an actual gap in the language rules that needs to
500 -- be fixed by the ARG. ???
502 -------------------------------
503 -- Apply_Accessibility_Check --
504 -------------------------------
506 procedure Apply_Accessibility_Check
508 Built_In_Place
: Boolean := False)
513 -- Note: we skip the accessibility check for the VM case, since
514 -- there does not seem to be any practical way of implementing it.
516 if Ada_Version
>= Ada_05
517 and then Tagged_Type_Expansion
518 and then Is_Class_Wide_Type
(DesigT
)
519 and then not Scope_Suppress
(Accessibility_Check
)
521 (Type_Access_Level
(Etype
(Exp
)) > Type_Access_Level
(PtrT
)
523 (Is_Class_Wide_Type
(Etype
(Exp
))
524 and then Scope
(PtrT
) /= Current_Scope
))
526 -- If the allocator was built in place Ref is already a reference
527 -- to the access object initialized to the result of the allocator
528 -- (see Exp_Ch6.Make_Build_In_Place_Call_In_Allocator). Otherwise
529 -- it is the entity associated with the object containing the
530 -- address of the allocated object.
532 if Built_In_Place
then
533 Ref_Node
:= New_Copy
(Ref
);
535 Ref_Node
:= New_Reference_To
(Ref
, Loc
);
539 Make_Raise_Program_Error
(Loc
,
543 Build_Get_Access_Level
(Loc
,
544 Make_Attribute_Reference
(Loc
,
546 Attribute_Name
=> Name_Tag
)),
548 Make_Integer_Literal
(Loc
,
549 Type_Access_Level
(PtrT
))),
550 Reason
=> PE_Accessibility_Check_Failed
));
552 end Apply_Accessibility_Check
;
556 Indic
: constant Node_Id
:= Subtype_Mark
(Expression
(N
));
557 T
: constant Entity_Id
:= Entity
(Indic
);
562 TagT
: Entity_Id
:= Empty
;
563 -- Type used as source for tag assignment
565 TagR
: Node_Id
:= Empty
;
566 -- Target reference for tag assignment
568 Aggr_In_Place
: constant Boolean := Is_Delayed_Aggregate
(Exp
);
570 Tag_Assign
: Node_Id
;
573 -- Start of processing for Expand_Allocator_Expression
576 if Is_Tagged_Type
(T
) or else Needs_Finalization
(T
) then
578 if Is_CPP_Constructor_Call
(Exp
) then
581 -- Pnnn : constant ptr_T := new (T); Init (Pnnn.all,...); Pnnn
583 -- Allocate the object with no expression
585 Node
:= Relocate_Node
(N
);
586 Set_Expression
(Node
, New_Reference_To
(Etype
(Exp
), Loc
));
588 -- Avoid its expansion to avoid generating a call to the default
593 Temp
:= Make_Temporary
(Loc
, 'P', N
);
596 Make_Object_Declaration
(Loc
,
597 Defining_Identifier
=> Temp
,
598 Constant_Present
=> True,
599 Object_Definition
=> New_Reference_To
(PtrT
, Loc
),
600 Expression
=> Node
));
602 Apply_Accessibility_Check
(Temp
);
604 -- Locate the enclosing list and insert the C++ constructor call
611 while not Is_List_Member
(P
) loop
615 Insert_List_After_And_Analyze
(P
,
616 Build_Initialization_Call
(Loc
,
618 Make_Explicit_Dereference
(Loc
,
619 Prefix
=> New_Reference_To
(Temp
, Loc
)),
621 Constructor_Ref
=> Exp
));
624 Rewrite
(N
, New_Reference_To
(Temp
, Loc
));
625 Analyze_And_Resolve
(N
, PtrT
);
629 -- Ada 2005 (AI-318-02): If the initialization expression is a call
630 -- to a build-in-place function, then access to the allocated object
631 -- must be passed to the function. Currently we limit such functions
632 -- to those with constrained limited result subtypes, but eventually
633 -- we plan to expand the allowed forms of functions that are treated
634 -- as build-in-place.
636 if Ada_Version
>= Ada_05
637 and then Is_Build_In_Place_Function_Call
(Exp
)
639 Make_Build_In_Place_Call_In_Allocator
(N
, Exp
);
640 Apply_Accessibility_Check
(N
, Built_In_Place
=> True);
644 -- Actions inserted before:
645 -- Temp : constant ptr_T := new T'(Expression);
646 -- <no CW> Temp._tag := T'tag;
647 -- <CTRL> Adjust (Finalizable (Temp.all));
648 -- <CTRL> Attach_To_Final_List (Finalizable (Temp.all));
650 -- We analyze by hand the new internal allocator to avoid
651 -- any recursion and inappropriate call to Initialize
653 -- We don't want to remove side effects when the expression must be
654 -- built in place. In the case of a build-in-place function call,
655 -- that could lead to a duplication of the call, which was already
656 -- substituted for the allocator.
658 if not Aggr_In_Place
then
659 Remove_Side_Effects
(Exp
);
662 Temp
:= Make_Temporary
(Loc
, 'P', N
);
664 -- For a class wide allocation generate the following code:
666 -- type Equiv_Record is record ... end record;
667 -- implicit subtype CW is <Class_Wide_Subytpe>;
668 -- temp : PtrT := new CW'(CW!(expr));
670 if Is_Class_Wide_Type
(T
) then
671 Expand_Subtype_From_Expr
(Empty
, T
, Indic
, Exp
);
673 -- Ada 2005 (AI-251): If the expression is a class-wide interface
674 -- object we generate code to move up "this" to reference the
675 -- base of the object before allocating the new object.
677 -- Note that Exp'Address is recursively expanded into a call
678 -- to Base_Address (Exp.Tag)
680 if Is_Class_Wide_Type
(Etype
(Exp
))
681 and then Is_Interface
(Etype
(Exp
))
682 and then Tagged_Type_Expansion
686 Unchecked_Convert_To
(Entity
(Indic
),
687 Make_Explicit_Dereference
(Loc
,
688 Unchecked_Convert_To
(RTE
(RE_Tag_Ptr
),
689 Make_Attribute_Reference
(Loc
,
691 Attribute_Name
=> Name_Address
)))));
696 Unchecked_Convert_To
(Entity
(Indic
), Exp
));
699 Analyze_And_Resolve
(Expression
(N
), Entity
(Indic
));
702 -- Keep separate the management of allocators returning interfaces
704 if not Is_Interface
(Directly_Designated_Type
(PtrT
)) then
705 if Aggr_In_Place
then
707 Make_Object_Declaration
(Loc
,
708 Defining_Identifier
=> Temp
,
709 Object_Definition
=> New_Reference_To
(PtrT
, Loc
),
712 New_Reference_To
(Etype
(Exp
), Loc
)));
714 -- Copy the Comes_From_Source flag for the allocator we just
715 -- built, since logically this allocator is a replacement of
716 -- the original allocator node. This is for proper handling of
717 -- restriction No_Implicit_Heap_Allocations.
719 Set_Comes_From_Source
720 (Expression
(Tmp_Node
), Comes_From_Source
(N
));
722 Set_No_Initialization
(Expression
(Tmp_Node
));
723 Insert_Action
(N
, Tmp_Node
);
725 if Needs_Finalization
(T
)
726 and then Ekind
(PtrT
) = E_Anonymous_Access_Type
728 -- Create local finalization list for access parameter
730 Flist
:= Get_Allocator_Final_List
(N
, Base_Type
(T
), PtrT
);
733 Convert_Aggr_In_Allocator
(N
, Tmp_Node
, Exp
);
736 Node
:= Relocate_Node
(N
);
739 Make_Object_Declaration
(Loc
,
740 Defining_Identifier
=> Temp
,
741 Constant_Present
=> True,
742 Object_Definition
=> New_Reference_To
(PtrT
, Loc
),
743 Expression
=> Node
));
746 -- Ada 2005 (AI-251): Handle allocators whose designated type is an
747 -- interface type. In this case we use the type of the qualified
748 -- expression to allocate the object.
752 Def_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
757 Make_Full_Type_Declaration
(Loc
,
758 Defining_Identifier
=> Def_Id
,
760 Make_Access_To_Object_Definition
(Loc
,
762 Null_Exclusion_Present
=> False,
763 Constant_Present
=> False,
764 Subtype_Indication
=>
765 New_Reference_To
(Etype
(Exp
), Loc
)));
767 Insert_Action
(N
, New_Decl
);
769 -- Inherit the final chain to ensure that the expansion of the
770 -- aggregate is correct in case of controlled types
772 if Needs_Finalization
(Directly_Designated_Type
(PtrT
)) then
773 Set_Associated_Final_Chain
(Def_Id
,
774 Associated_Final_Chain
(PtrT
));
777 -- Declare the object using the previous type declaration
779 if Aggr_In_Place
then
781 Make_Object_Declaration
(Loc
,
782 Defining_Identifier
=> Temp
,
783 Object_Definition
=> New_Reference_To
(Def_Id
, Loc
),
786 New_Reference_To
(Etype
(Exp
), Loc
)));
788 -- Copy the Comes_From_Source flag for the allocator we just
789 -- built, since logically this allocator is a replacement of
790 -- the original allocator node. This is for proper handling
791 -- of restriction No_Implicit_Heap_Allocations.
793 Set_Comes_From_Source
794 (Expression
(Tmp_Node
), Comes_From_Source
(N
));
796 Set_No_Initialization
(Expression
(Tmp_Node
));
797 Insert_Action
(N
, Tmp_Node
);
799 if Needs_Finalization
(T
)
800 and then Ekind
(PtrT
) = E_Anonymous_Access_Type
802 -- Create local finalization list for access parameter
805 Get_Allocator_Final_List
(N
, Base_Type
(T
), PtrT
);
808 Convert_Aggr_In_Allocator
(N
, Tmp_Node
, Exp
);
810 Node
:= Relocate_Node
(N
);
813 Make_Object_Declaration
(Loc
,
814 Defining_Identifier
=> Temp
,
815 Constant_Present
=> True,
816 Object_Definition
=> New_Reference_To
(Def_Id
, Loc
),
817 Expression
=> Node
));
820 -- Generate an additional object containing the address of the
821 -- returned object. The type of this second object declaration
822 -- is the correct type required for the common processing that
823 -- is still performed by this subprogram. The displacement of
824 -- this pointer to reference the component associated with the
825 -- interface type will be done at the end of common processing.
828 Make_Object_Declaration
(Loc
,
829 Defining_Identifier
=> Make_Temporary
(Loc
, 'P'),
830 Object_Definition
=> New_Reference_To
(PtrT
, Loc
),
831 Expression
=> Unchecked_Convert_To
(PtrT
,
832 New_Reference_To
(Temp
, Loc
)));
834 Insert_Action
(N
, New_Decl
);
836 Tmp_Node
:= New_Decl
;
837 Temp
:= Defining_Identifier
(New_Decl
);
841 Apply_Accessibility_Check
(Temp
);
843 -- Generate the tag assignment
845 -- Suppress the tag assignment when VM_Target because VM tags are
846 -- represented implicitly in objects.
848 if not Tagged_Type_Expansion
then
851 -- Ada 2005 (AI-251): Suppress the tag assignment with class-wide
852 -- interface objects because in this case the tag does not change.
854 elsif Is_Interface
(Directly_Designated_Type
(Etype
(N
))) then
855 pragma Assert
(Is_Class_Wide_Type
856 (Directly_Designated_Type
(Etype
(N
))));
859 elsif Is_Tagged_Type
(T
) and then not Is_Class_Wide_Type
(T
) then
861 TagR
:= New_Reference_To
(Temp
, Loc
);
863 elsif Is_Private_Type
(T
)
864 and then Is_Tagged_Type
(Underlying_Type
(T
))
866 TagT
:= Underlying_Type
(T
);
868 Unchecked_Convert_To
(Underlying_Type
(T
),
869 Make_Explicit_Dereference
(Loc
,
870 Prefix
=> New_Reference_To
(Temp
, Loc
)));
873 if Present
(TagT
) then
875 Make_Assignment_Statement
(Loc
,
877 Make_Selected_Component
(Loc
,
880 New_Reference_To
(First_Tag_Component
(TagT
), Loc
)),
883 Unchecked_Convert_To
(RTE
(RE_Tag
),
885 (Elists
.Node
(First_Elmt
(Access_Disp_Table
(TagT
))),
888 -- The previous assignment has to be done in any case
890 Set_Assignment_OK
(Name
(Tag_Assign
));
891 Insert_Action
(N
, Tag_Assign
);
894 if Needs_Finalization
(DesigT
)
895 and then Needs_Finalization
(T
)
899 Apool
: constant Entity_Id
:=
900 Associated_Storage_Pool
(PtrT
);
903 -- If it is an allocation on the secondary stack (i.e. a value
904 -- returned from a function), the object is attached on the
905 -- caller side as soon as the call is completed (see
906 -- Expand_Ctrl_Function_Call)
908 if Is_RTE
(Apool
, RE_SS_Pool
) then
910 F
: constant Entity_Id
:= Make_Temporary
(Loc
, 'F');
913 Make_Object_Declaration
(Loc
,
914 Defining_Identifier
=> F
,
916 New_Reference_To
(RTE
(RE_Finalizable_Ptr
), Loc
)));
917 Flist
:= New_Reference_To
(F
, Loc
);
918 Attach
:= Make_Integer_Literal
(Loc
, 1);
921 -- Normal case, not a secondary stack allocation
924 if Needs_Finalization
(T
)
925 and then Ekind
(PtrT
) = E_Anonymous_Access_Type
927 -- Create local finalization list for access parameter
930 Get_Allocator_Final_List
(N
, Base_Type
(T
), PtrT
);
932 Flist
:= Find_Final_List
(PtrT
);
935 Attach
:= Make_Integer_Literal
(Loc
, 2);
938 -- Generate an Adjust call if the object will be moved. In Ada
939 -- 2005, the object may be inherently limited, in which case
940 -- there is no Adjust procedure, and the object is built in
941 -- place. In Ada 95, the object can be limited but not
942 -- inherently limited if this allocator came from a return
943 -- statement (we're allocating the result on the secondary
944 -- stack). In that case, the object will be moved, so we _do_
948 and then not Is_Inherently_Limited_Type
(T
)
954 -- An unchecked conversion is needed in the classwide
955 -- case because the designated type can be an ancestor of
956 -- the subtype mark of the allocator.
958 Unchecked_Convert_To
(T
,
959 Make_Explicit_Dereference
(Loc
,
960 Prefix
=> New_Reference_To
(Temp
, Loc
))),
964 With_Attach
=> Attach
,
970 Rewrite
(N
, New_Reference_To
(Temp
, Loc
));
971 Analyze_And_Resolve
(N
, PtrT
);
973 -- Ada 2005 (AI-251): Displace the pointer to reference the record
974 -- component containing the secondary dispatch table of the interface
977 if Is_Interface
(Directly_Designated_Type
(PtrT
)) then
978 Displace_Allocator_Pointer
(N
);
981 elsif Aggr_In_Place
then
982 Temp
:= Make_Temporary
(Loc
, 'P', N
);
984 Make_Object_Declaration
(Loc
,
985 Defining_Identifier
=> Temp
,
986 Object_Definition
=> New_Reference_To
(PtrT
, Loc
),
987 Expression
=> Make_Allocator
(Loc
,
988 New_Reference_To
(Etype
(Exp
), Loc
)));
990 -- Copy the Comes_From_Source flag for the allocator we just built,
991 -- since logically this allocator is a replacement of the original
992 -- allocator node. This is for proper handling of restriction
993 -- No_Implicit_Heap_Allocations.
995 Set_Comes_From_Source
996 (Expression
(Tmp_Node
), Comes_From_Source
(N
));
998 Set_No_Initialization
(Expression
(Tmp_Node
));
999 Insert_Action
(N
, Tmp_Node
);
1000 Convert_Aggr_In_Allocator
(N
, Tmp_Node
, Exp
);
1001 Rewrite
(N
, New_Reference_To
(Temp
, Loc
));
1002 Analyze_And_Resolve
(N
, PtrT
);
1004 elsif Is_Access_Type
(T
)
1005 and then Can_Never_Be_Null
(T
)
1007 Install_Null_Excluding_Check
(Exp
);
1009 elsif Is_Access_Type
(DesigT
)
1010 and then Nkind
(Exp
) = N_Allocator
1011 and then Nkind
(Expression
(Exp
)) /= N_Qualified_Expression
1013 -- Apply constraint to designated subtype indication
1015 Apply_Constraint_Check
(Expression
(Exp
),
1016 Designated_Type
(DesigT
),
1017 No_Sliding
=> True);
1019 if Nkind
(Expression
(Exp
)) = N_Raise_Constraint_Error
then
1021 -- Propagate constraint_error to enclosing allocator
1023 Rewrite
(Exp
, New_Copy
(Expression
(Exp
)));
1027 -- type A is access T1;
1028 -- X : A := new T2'(...);
1029 -- T1 and T2 can be different subtypes, and we might need to check
1030 -- both constraints. First check against the type of the qualified
1033 Apply_Constraint_Check
(Exp
, T
, No_Sliding
=> True);
1035 if Do_Range_Check
(Exp
) then
1036 Set_Do_Range_Check
(Exp
, False);
1037 Generate_Range_Check
(Exp
, DesigT
, CE_Range_Check_Failed
);
1040 -- A check is also needed in cases where the designated subtype is
1041 -- constrained and differs from the subtype given in the qualified
1042 -- expression. Note that the check on the qualified expression does
1043 -- not allow sliding, but this check does (a relaxation from Ada 83).
1045 if Is_Constrained
(DesigT
)
1046 and then not Subtypes_Statically_Match
(T
, DesigT
)
1048 Apply_Constraint_Check
1049 (Exp
, DesigT
, No_Sliding
=> False);
1051 if Do_Range_Check
(Exp
) then
1052 Set_Do_Range_Check
(Exp
, False);
1053 Generate_Range_Check
(Exp
, DesigT
, CE_Range_Check_Failed
);
1057 -- For an access to unconstrained packed array, GIGI needs to see an
1058 -- expression with a constrained subtype in order to compute the
1059 -- proper size for the allocator.
1061 if Is_Array_Type
(T
)
1062 and then not Is_Constrained
(T
)
1063 and then Is_Packed
(T
)
1066 ConstrT
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
1067 Internal_Exp
: constant Node_Id
:= Relocate_Node
(Exp
);
1070 Make_Subtype_Declaration
(Loc
,
1071 Defining_Identifier
=> ConstrT
,
1072 Subtype_Indication
=>
1073 Make_Subtype_From_Expr
(Exp
, T
)));
1074 Freeze_Itype
(ConstrT
, Exp
);
1075 Rewrite
(Exp
, OK_Convert_To
(ConstrT
, Internal_Exp
));
1079 -- Ada 2005 (AI-318-02): If the initialization expression is a call
1080 -- to a build-in-place function, then access to the allocated object
1081 -- must be passed to the function. Currently we limit such functions
1082 -- to those with constrained limited result subtypes, but eventually
1083 -- we plan to expand the allowed forms of functions that are treated
1084 -- as build-in-place.
1086 if Ada_Version
>= Ada_05
1087 and then Is_Build_In_Place_Function_Call
(Exp
)
1089 Make_Build_In_Place_Call_In_Allocator
(N
, Exp
);
1094 when RE_Not_Available
=>
1096 end Expand_Allocator_Expression
;
1098 -----------------------------
1099 -- Expand_Array_Comparison --
1100 -----------------------------
1102 -- Expansion is only required in the case of array types. For the unpacked
1103 -- case, an appropriate runtime routine is called. For packed cases, and
1104 -- also in some other cases where a runtime routine cannot be called, the
1105 -- form of the expansion is:
1107 -- [body for greater_nn; boolean_expression]
1109 -- The body is built by Make_Array_Comparison_Op, and the form of the
1110 -- Boolean expression depends on the operator involved.
1112 procedure Expand_Array_Comparison
(N
: Node_Id
) is
1113 Loc
: constant Source_Ptr
:= Sloc
(N
);
1114 Op1
: Node_Id
:= Left_Opnd
(N
);
1115 Op2
: Node_Id
:= Right_Opnd
(N
);
1116 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
1117 Ctyp
: constant Entity_Id
:= Component_Type
(Typ1
);
1120 Func_Body
: Node_Id
;
1121 Func_Name
: Entity_Id
;
1125 Byte_Addressable
: constant Boolean := System_Storage_Unit
= Byte
'Size;
1126 -- True for byte addressable target
1128 function Length_Less_Than_4
(Opnd
: Node_Id
) return Boolean;
1129 -- Returns True if the length of the given operand is known to be less
1130 -- than 4. Returns False if this length is known to be four or greater
1131 -- or is not known at compile time.
1133 ------------------------
1134 -- Length_Less_Than_4 --
1135 ------------------------
1137 function Length_Less_Than_4
(Opnd
: Node_Id
) return Boolean is
1138 Otyp
: constant Entity_Id
:= Etype
(Opnd
);
1141 if Ekind
(Otyp
) = E_String_Literal_Subtype
then
1142 return String_Literal_Length
(Otyp
) < 4;
1146 Ityp
: constant Entity_Id
:= Etype
(First_Index
(Otyp
));
1147 Lo
: constant Node_Id
:= Type_Low_Bound
(Ityp
);
1148 Hi
: constant Node_Id
:= Type_High_Bound
(Ityp
);
1153 if Compile_Time_Known_Value
(Lo
) then
1154 Lov
:= Expr_Value
(Lo
);
1159 if Compile_Time_Known_Value
(Hi
) then
1160 Hiv
:= Expr_Value
(Hi
);
1165 return Hiv
< Lov
+ 3;
1168 end Length_Less_Than_4
;
1170 -- Start of processing for Expand_Array_Comparison
1173 -- Deal first with unpacked case, where we can call a runtime routine
1174 -- except that we avoid this for targets for which are not addressable
1175 -- by bytes, and for the JVM/CIL, since they do not support direct
1176 -- addressing of array components.
1178 if not Is_Bit_Packed_Array
(Typ1
)
1179 and then Byte_Addressable
1180 and then VM_Target
= No_VM
1182 -- The call we generate is:
1184 -- Compare_Array_xn[_Unaligned]
1185 -- (left'address, right'address, left'length, right'length) <op> 0
1187 -- x = U for unsigned, S for signed
1188 -- n = 8,16,32,64 for component size
1189 -- Add _Unaligned if length < 4 and component size is 8.
1190 -- <op> is the standard comparison operator
1192 if Component_Size
(Typ1
) = 8 then
1193 if Length_Less_Than_4
(Op1
)
1195 Length_Less_Than_4
(Op2
)
1197 if Is_Unsigned_Type
(Ctyp
) then
1198 Comp
:= RE_Compare_Array_U8_Unaligned
;
1200 Comp
:= RE_Compare_Array_S8_Unaligned
;
1204 if Is_Unsigned_Type
(Ctyp
) then
1205 Comp
:= RE_Compare_Array_U8
;
1207 Comp
:= RE_Compare_Array_S8
;
1211 elsif Component_Size
(Typ1
) = 16 then
1212 if Is_Unsigned_Type
(Ctyp
) then
1213 Comp
:= RE_Compare_Array_U16
;
1215 Comp
:= RE_Compare_Array_S16
;
1218 elsif Component_Size
(Typ1
) = 32 then
1219 if Is_Unsigned_Type
(Ctyp
) then
1220 Comp
:= RE_Compare_Array_U32
;
1222 Comp
:= RE_Compare_Array_S32
;
1225 else pragma Assert
(Component_Size
(Typ1
) = 64);
1226 if Is_Unsigned_Type
(Ctyp
) then
1227 Comp
:= RE_Compare_Array_U64
;
1229 Comp
:= RE_Compare_Array_S64
;
1233 Remove_Side_Effects
(Op1
, Name_Req
=> True);
1234 Remove_Side_Effects
(Op2
, Name_Req
=> True);
1237 Make_Function_Call
(Sloc
(Op1
),
1238 Name
=> New_Occurrence_Of
(RTE
(Comp
), Loc
),
1240 Parameter_Associations
=> New_List
(
1241 Make_Attribute_Reference
(Loc
,
1242 Prefix
=> Relocate_Node
(Op1
),
1243 Attribute_Name
=> Name_Address
),
1245 Make_Attribute_Reference
(Loc
,
1246 Prefix
=> Relocate_Node
(Op2
),
1247 Attribute_Name
=> Name_Address
),
1249 Make_Attribute_Reference
(Loc
,
1250 Prefix
=> Relocate_Node
(Op1
),
1251 Attribute_Name
=> Name_Length
),
1253 Make_Attribute_Reference
(Loc
,
1254 Prefix
=> Relocate_Node
(Op2
),
1255 Attribute_Name
=> Name_Length
))));
1258 Make_Integer_Literal
(Sloc
(Op2
),
1261 Analyze_And_Resolve
(Op1
, Standard_Integer
);
1262 Analyze_And_Resolve
(Op2
, Standard_Integer
);
1266 -- Cases where we cannot make runtime call
1268 -- For (a <= b) we convert to not (a > b)
1270 if Chars
(N
) = Name_Op_Le
then
1276 Right_Opnd
=> Op2
)));
1277 Analyze_And_Resolve
(N
, Standard_Boolean
);
1280 -- For < the Boolean expression is
1281 -- greater__nn (op2, op1)
1283 elsif Chars
(N
) = Name_Op_Lt
then
1284 Func_Body
:= Make_Array_Comparison_Op
(Typ1
, N
);
1288 Op1
:= Right_Opnd
(N
);
1289 Op2
:= Left_Opnd
(N
);
1291 -- For (a >= b) we convert to not (a < b)
1293 elsif Chars
(N
) = Name_Op_Ge
then
1299 Right_Opnd
=> Op2
)));
1300 Analyze_And_Resolve
(N
, Standard_Boolean
);
1303 -- For > the Boolean expression is
1304 -- greater__nn (op1, op2)
1307 pragma Assert
(Chars
(N
) = Name_Op_Gt
);
1308 Func_Body
:= Make_Array_Comparison_Op
(Typ1
, N
);
1311 Func_Name
:= Defining_Unit_Name
(Specification
(Func_Body
));
1313 Make_Function_Call
(Loc
,
1314 Name
=> New_Reference_To
(Func_Name
, Loc
),
1315 Parameter_Associations
=> New_List
(Op1
, Op2
));
1317 Insert_Action
(N
, Func_Body
);
1319 Analyze_And_Resolve
(N
, Standard_Boolean
);
1322 when RE_Not_Available
=>
1324 end Expand_Array_Comparison
;
1326 ---------------------------
1327 -- Expand_Array_Equality --
1328 ---------------------------
1330 -- Expand an equality function for multi-dimensional arrays. Here is an
1331 -- example of such a function for Nb_Dimension = 2
1333 -- function Enn (A : atyp; B : btyp) return boolean is
1335 -- if (A'length (1) = 0 or else A'length (2) = 0)
1337 -- (B'length (1) = 0 or else B'length (2) = 0)
1339 -- return True; -- RM 4.5.2(22)
1342 -- if A'length (1) /= B'length (1)
1344 -- A'length (2) /= B'length (2)
1346 -- return False; -- RM 4.5.2(23)
1350 -- A1 : Index_T1 := A'first (1);
1351 -- B1 : Index_T1 := B'first (1);
1355 -- A2 : Index_T2 := A'first (2);
1356 -- B2 : Index_T2 := B'first (2);
1359 -- if A (A1, A2) /= B (B1, B2) then
1363 -- exit when A2 = A'last (2);
1364 -- A2 := Index_T2'succ (A2);
1365 -- B2 := Index_T2'succ (B2);
1369 -- exit when A1 = A'last (1);
1370 -- A1 := Index_T1'succ (A1);
1371 -- B1 := Index_T1'succ (B1);
1378 -- Note on the formal types used (atyp and btyp). If either of the arrays
1379 -- is of a private type, we use the underlying type, and do an unchecked
1380 -- conversion of the actual. If either of the arrays has a bound depending
1381 -- on a discriminant, then we use the base type since otherwise we have an
1382 -- escaped discriminant in the function.
1384 -- If both arrays are constrained and have the same bounds, we can generate
1385 -- a loop with an explicit iteration scheme using a 'Range attribute over
1388 function Expand_Array_Equality
1393 Typ
: Entity_Id
) return Node_Id
1395 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
1396 Decls
: constant List_Id
:= New_List
;
1397 Index_List1
: constant List_Id
:= New_List
;
1398 Index_List2
: constant List_Id
:= New_List
;
1402 Func_Name
: Entity_Id
;
1403 Func_Body
: Node_Id
;
1405 A
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uA
);
1406 B
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uB
);
1410 -- The parameter types to be used for the formals
1415 Num
: Int
) return Node_Id
;
1416 -- This builds the attribute reference Arr'Nam (Expr)
1418 function Component_Equality
(Typ
: Entity_Id
) return Node_Id
;
1419 -- Create one statement to compare corresponding components, designated
1420 -- by a full set of indices.
1422 function Get_Arg_Type
(N
: Node_Id
) return Entity_Id
;
1423 -- Given one of the arguments, computes the appropriate type to be used
1424 -- for that argument in the corresponding function formal
1426 function Handle_One_Dimension
1428 Index
: Node_Id
) return Node_Id
;
1429 -- This procedure returns the following code
1432 -- Bn : Index_T := B'First (N);
1436 -- exit when An = A'Last (N);
1437 -- An := Index_T'Succ (An)
1438 -- Bn := Index_T'Succ (Bn)
1442 -- If both indices are constrained and identical, the procedure
1443 -- returns a simpler loop:
1445 -- for An in A'Range (N) loop
1449 -- N is the dimension for which we are generating a loop. Index is the
1450 -- N'th index node, whose Etype is Index_Type_n in the above code. The
1451 -- xxx statement is either the loop or declare for the next dimension
1452 -- or if this is the last dimension the comparison of corresponding
1453 -- components of the arrays.
1455 -- The actual way the code works is to return the comparison of
1456 -- corresponding components for the N+1 call. That's neater!
1458 function Test_Empty_Arrays
return Node_Id
;
1459 -- This function constructs the test for both arrays being empty
1460 -- (A'length (1) = 0 or else A'length (2) = 0 or else ...)
1462 -- (B'length (1) = 0 or else B'length (2) = 0 or else ...)
1464 function Test_Lengths_Correspond
return Node_Id
;
1465 -- This function constructs the test for arrays having different lengths
1466 -- in at least one index position, in which case the resulting code is:
1468 -- A'length (1) /= B'length (1)
1470 -- A'length (2) /= B'length (2)
1481 Num
: Int
) return Node_Id
1485 Make_Attribute_Reference
(Loc
,
1486 Attribute_Name
=> Nam
,
1487 Prefix
=> New_Reference_To
(Arr
, Loc
),
1488 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, Num
)));
1491 ------------------------
1492 -- Component_Equality --
1493 ------------------------
1495 function Component_Equality
(Typ
: Entity_Id
) return Node_Id
is
1500 -- if a(i1...) /= b(j1...) then return false; end if;
1503 Make_Indexed_Component
(Loc
,
1504 Prefix
=> Make_Identifier
(Loc
, Chars
(A
)),
1505 Expressions
=> Index_List1
);
1508 Make_Indexed_Component
(Loc
,
1509 Prefix
=> Make_Identifier
(Loc
, Chars
(B
)),
1510 Expressions
=> Index_List2
);
1512 Test
:= Expand_Composite_Equality
1513 (Nod
, Component_Type
(Typ
), L
, R
, Decls
);
1515 -- If some (sub)component is an unchecked_union, the whole operation
1516 -- will raise program error.
1518 if Nkind
(Test
) = N_Raise_Program_Error
then
1520 -- This node is going to be inserted at a location where a
1521 -- statement is expected: clear its Etype so analysis will set
1522 -- it to the expected Standard_Void_Type.
1524 Set_Etype
(Test
, Empty
);
1529 Make_Implicit_If_Statement
(Nod
,
1530 Condition
=> Make_Op_Not
(Loc
, Right_Opnd
=> Test
),
1531 Then_Statements
=> New_List
(
1532 Make_Simple_Return_Statement
(Loc
,
1533 Expression
=> New_Occurrence_Of
(Standard_False
, Loc
))));
1535 end Component_Equality
;
1541 function Get_Arg_Type
(N
: Node_Id
) return Entity_Id
is
1552 T
:= Underlying_Type
(T
);
1554 X
:= First_Index
(T
);
1555 while Present
(X
) loop
1556 if Denotes_Discriminant
(Type_Low_Bound
(Etype
(X
)))
1558 Denotes_Discriminant
(Type_High_Bound
(Etype
(X
)))
1571 --------------------------
1572 -- Handle_One_Dimension --
1573 ---------------------------
1575 function Handle_One_Dimension
1577 Index
: Node_Id
) return Node_Id
1579 Need_Separate_Indexes
: constant Boolean :=
1581 or else not Is_Constrained
(Ltyp
);
1582 -- If the index types are identical, and we are working with
1583 -- constrained types, then we can use the same index for both
1586 An
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
1589 Index_T
: Entity_Id
;
1594 if N
> Number_Dimensions
(Ltyp
) then
1595 return Component_Equality
(Ltyp
);
1598 -- Case where we generate a loop
1600 Index_T
:= Base_Type
(Etype
(Index
));
1602 if Need_Separate_Indexes
then
1603 Bn
:= Make_Temporary
(Loc
, 'B');
1608 Append
(New_Reference_To
(An
, Loc
), Index_List1
);
1609 Append
(New_Reference_To
(Bn
, Loc
), Index_List2
);
1611 Stm_List
:= New_List
(
1612 Handle_One_Dimension
(N
+ 1, Next_Index
(Index
)));
1614 if Need_Separate_Indexes
then
1616 -- Generate guard for loop, followed by increments of indices
1618 Append_To
(Stm_List
,
1619 Make_Exit_Statement
(Loc
,
1622 Left_Opnd
=> New_Reference_To
(An
, Loc
),
1623 Right_Opnd
=> Arr_Attr
(A
, Name_Last
, N
))));
1625 Append_To
(Stm_List
,
1626 Make_Assignment_Statement
(Loc
,
1627 Name
=> New_Reference_To
(An
, Loc
),
1629 Make_Attribute_Reference
(Loc
,
1630 Prefix
=> New_Reference_To
(Index_T
, Loc
),
1631 Attribute_Name
=> Name_Succ
,
1632 Expressions
=> New_List
(New_Reference_To
(An
, Loc
)))));
1634 Append_To
(Stm_List
,
1635 Make_Assignment_Statement
(Loc
,
1636 Name
=> New_Reference_To
(Bn
, Loc
),
1638 Make_Attribute_Reference
(Loc
,
1639 Prefix
=> New_Reference_To
(Index_T
, Loc
),
1640 Attribute_Name
=> Name_Succ
,
1641 Expressions
=> New_List
(New_Reference_To
(Bn
, Loc
)))));
1644 -- If separate indexes, we need a declare block for An and Bn, and a
1645 -- loop without an iteration scheme.
1647 if Need_Separate_Indexes
then
1649 Make_Implicit_Loop_Statement
(Nod
, Statements
=> Stm_List
);
1652 Make_Block_Statement
(Loc
,
1653 Declarations
=> New_List
(
1654 Make_Object_Declaration
(Loc
,
1655 Defining_Identifier
=> An
,
1656 Object_Definition
=> New_Reference_To
(Index_T
, Loc
),
1657 Expression
=> Arr_Attr
(A
, Name_First
, N
)),
1659 Make_Object_Declaration
(Loc
,
1660 Defining_Identifier
=> Bn
,
1661 Object_Definition
=> New_Reference_To
(Index_T
, Loc
),
1662 Expression
=> Arr_Attr
(B
, Name_First
, N
))),
1664 Handled_Statement_Sequence
=>
1665 Make_Handled_Sequence_Of_Statements
(Loc
,
1666 Statements
=> New_List
(Loop_Stm
)));
1668 -- If no separate indexes, return loop statement with explicit
1669 -- iteration scheme on its own
1673 Make_Implicit_Loop_Statement
(Nod
,
1674 Statements
=> Stm_List
,
1676 Make_Iteration_Scheme
(Loc
,
1677 Loop_Parameter_Specification
=>
1678 Make_Loop_Parameter_Specification
(Loc
,
1679 Defining_Identifier
=> An
,
1680 Discrete_Subtype_Definition
=>
1681 Arr_Attr
(A
, Name_Range
, N
))));
1684 end Handle_One_Dimension
;
1686 -----------------------
1687 -- Test_Empty_Arrays --
1688 -----------------------
1690 function Test_Empty_Arrays
return Node_Id
is
1700 for J
in 1 .. Number_Dimensions
(Ltyp
) loop
1703 Left_Opnd
=> Arr_Attr
(A
, Name_Length
, J
),
1704 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0));
1708 Left_Opnd
=> Arr_Attr
(B
, Name_Length
, J
),
1709 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0));
1718 Left_Opnd
=> Relocate_Node
(Alist
),
1719 Right_Opnd
=> Atest
);
1723 Left_Opnd
=> Relocate_Node
(Blist
),
1724 Right_Opnd
=> Btest
);
1731 Right_Opnd
=> Blist
);
1732 end Test_Empty_Arrays
;
1734 -----------------------------
1735 -- Test_Lengths_Correspond --
1736 -----------------------------
1738 function Test_Lengths_Correspond
return Node_Id
is
1744 for J
in 1 .. Number_Dimensions
(Ltyp
) loop
1747 Left_Opnd
=> Arr_Attr
(A
, Name_Length
, J
),
1748 Right_Opnd
=> Arr_Attr
(B
, Name_Length
, J
));
1755 Left_Opnd
=> Relocate_Node
(Result
),
1756 Right_Opnd
=> Rtest
);
1761 end Test_Lengths_Correspond
;
1763 -- Start of processing for Expand_Array_Equality
1766 Ltyp
:= Get_Arg_Type
(Lhs
);
1767 Rtyp
:= Get_Arg_Type
(Rhs
);
1769 -- For now, if the argument types are not the same, go to the base type,
1770 -- since the code assumes that the formals have the same type. This is
1771 -- fixable in future ???
1773 if Ltyp
/= Rtyp
then
1774 Ltyp
:= Base_Type
(Ltyp
);
1775 Rtyp
:= Base_Type
(Rtyp
);
1776 pragma Assert
(Ltyp
= Rtyp
);
1779 -- Build list of formals for function
1781 Formals
:= New_List
(
1782 Make_Parameter_Specification
(Loc
,
1783 Defining_Identifier
=> A
,
1784 Parameter_Type
=> New_Reference_To
(Ltyp
, Loc
)),
1786 Make_Parameter_Specification
(Loc
,
1787 Defining_Identifier
=> B
,
1788 Parameter_Type
=> New_Reference_To
(Rtyp
, Loc
)));
1790 Func_Name
:= Make_Temporary
(Loc
, 'E');
1792 -- Build statement sequence for function
1795 Make_Subprogram_Body
(Loc
,
1797 Make_Function_Specification
(Loc
,
1798 Defining_Unit_Name
=> Func_Name
,
1799 Parameter_Specifications
=> Formals
,
1800 Result_Definition
=> New_Reference_To
(Standard_Boolean
, Loc
)),
1802 Declarations
=> Decls
,
1804 Handled_Statement_Sequence
=>
1805 Make_Handled_Sequence_Of_Statements
(Loc
,
1806 Statements
=> New_List
(
1808 Make_Implicit_If_Statement
(Nod
,
1809 Condition
=> Test_Empty_Arrays
,
1810 Then_Statements
=> New_List
(
1811 Make_Simple_Return_Statement
(Loc
,
1813 New_Occurrence_Of
(Standard_True
, Loc
)))),
1815 Make_Implicit_If_Statement
(Nod
,
1816 Condition
=> Test_Lengths_Correspond
,
1817 Then_Statements
=> New_List
(
1818 Make_Simple_Return_Statement
(Loc
,
1820 New_Occurrence_Of
(Standard_False
, Loc
)))),
1822 Handle_One_Dimension
(1, First_Index
(Ltyp
)),
1824 Make_Simple_Return_Statement
(Loc
,
1825 Expression
=> New_Occurrence_Of
(Standard_True
, Loc
)))));
1827 Set_Has_Completion
(Func_Name
, True);
1828 Set_Is_Inlined
(Func_Name
);
1830 -- If the array type is distinct from the type of the arguments, it
1831 -- is the full view of a private type. Apply an unchecked conversion
1832 -- to insure that analysis of the call succeeds.
1842 or else Base_Type
(Etype
(Lhs
)) /= Base_Type
(Ltyp
)
1844 L
:= OK_Convert_To
(Ltyp
, Lhs
);
1848 or else Base_Type
(Etype
(Rhs
)) /= Base_Type
(Rtyp
)
1850 R
:= OK_Convert_To
(Rtyp
, Rhs
);
1853 Actuals
:= New_List
(L
, R
);
1856 Append_To
(Bodies
, Func_Body
);
1859 Make_Function_Call
(Loc
,
1860 Name
=> New_Reference_To
(Func_Name
, Loc
),
1861 Parameter_Associations
=> Actuals
);
1862 end Expand_Array_Equality
;
1864 -----------------------------
1865 -- Expand_Boolean_Operator --
1866 -----------------------------
1868 -- Note that we first get the actual subtypes of the operands, since we
1869 -- always want to deal with types that have bounds.
1871 procedure Expand_Boolean_Operator
(N
: Node_Id
) is
1872 Typ
: constant Entity_Id
:= Etype
(N
);
1875 -- Special case of bit packed array where both operands are known to be
1876 -- properly aligned. In this case we use an efficient run time routine
1877 -- to carry out the operation (see System.Bit_Ops).
1879 if Is_Bit_Packed_Array
(Typ
)
1880 and then not Is_Possibly_Unaligned_Object
(Left_Opnd
(N
))
1881 and then not Is_Possibly_Unaligned_Object
(Right_Opnd
(N
))
1883 Expand_Packed_Boolean_Operator
(N
);
1887 -- For the normal non-packed case, the general expansion is to build
1888 -- function for carrying out the comparison (use Make_Boolean_Array_Op)
1889 -- and then inserting it into the tree. The original operator node is
1890 -- then rewritten as a call to this function. We also use this in the
1891 -- packed case if either operand is a possibly unaligned object.
1894 Loc
: constant Source_Ptr
:= Sloc
(N
);
1895 L
: constant Node_Id
:= Relocate_Node
(Left_Opnd
(N
));
1896 R
: constant Node_Id
:= Relocate_Node
(Right_Opnd
(N
));
1897 Func_Body
: Node_Id
;
1898 Func_Name
: Entity_Id
;
1901 Convert_To_Actual_Subtype
(L
);
1902 Convert_To_Actual_Subtype
(R
);
1903 Ensure_Defined
(Etype
(L
), N
);
1904 Ensure_Defined
(Etype
(R
), N
);
1905 Apply_Length_Check
(R
, Etype
(L
));
1907 if Nkind
(N
) = N_Op_Xor
then
1908 Silly_Boolean_Array_Xor_Test
(N
, Etype
(L
));
1911 if Nkind
(Parent
(N
)) = N_Assignment_Statement
1912 and then Safe_In_Place_Array_Op
(Name
(Parent
(N
)), L
, R
)
1914 Build_Boolean_Array_Proc_Call
(Parent
(N
), L
, R
);
1916 elsif Nkind
(Parent
(N
)) = N_Op_Not
1917 and then Nkind
(N
) = N_Op_And
1919 Safe_In_Place_Array_Op
(Name
(Parent
(Parent
(N
))), L
, R
)
1924 Func_Body
:= Make_Boolean_Array_Op
(Etype
(L
), N
);
1925 Func_Name
:= Defining_Unit_Name
(Specification
(Func_Body
));
1926 Insert_Action
(N
, Func_Body
);
1928 -- Now rewrite the expression with a call
1931 Make_Function_Call
(Loc
,
1932 Name
=> New_Reference_To
(Func_Name
, Loc
),
1933 Parameter_Associations
=>
1936 Make_Type_Conversion
1937 (Loc
, New_Reference_To
(Etype
(L
), Loc
), R
))));
1939 Analyze_And_Resolve
(N
, Typ
);
1942 end Expand_Boolean_Operator
;
1944 -------------------------------
1945 -- Expand_Composite_Equality --
1946 -------------------------------
1948 -- This function is only called for comparing internal fields of composite
1949 -- types when these fields are themselves composites. This is a special
1950 -- case because it is not possible to respect normal Ada visibility rules.
1952 function Expand_Composite_Equality
1957 Bodies
: List_Id
) return Node_Id
1959 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
1960 Full_Type
: Entity_Id
;
1965 if Is_Private_Type
(Typ
) then
1966 Full_Type
:= Underlying_Type
(Typ
);
1971 -- Defense against malformed private types with no completion the error
1972 -- will be diagnosed later by check_completion
1974 if No
(Full_Type
) then
1975 return New_Reference_To
(Standard_False
, Loc
);
1978 Full_Type
:= Base_Type
(Full_Type
);
1980 if Is_Array_Type
(Full_Type
) then
1982 -- If the operand is an elementary type other than a floating-point
1983 -- type, then we can simply use the built-in block bitwise equality,
1984 -- since the predefined equality operators always apply and bitwise
1985 -- equality is fine for all these cases.
1987 if Is_Elementary_Type
(Component_Type
(Full_Type
))
1988 and then not Is_Floating_Point_Type
(Component_Type
(Full_Type
))
1990 return Make_Op_Eq
(Loc
, Left_Opnd
=> Lhs
, Right_Opnd
=> Rhs
);
1992 -- For composite component types, and floating-point types, use the
1993 -- expansion. This deals with tagged component types (where we use
1994 -- the applicable equality routine) and floating-point, (where we
1995 -- need to worry about negative zeroes), and also the case of any
1996 -- composite type recursively containing such fields.
1999 return Expand_Array_Equality
(Nod
, Lhs
, Rhs
, Bodies
, Full_Type
);
2002 elsif Is_Tagged_Type
(Full_Type
) then
2004 -- Call the primitive operation "=" of this type
2006 if Is_Class_Wide_Type
(Full_Type
) then
2007 Full_Type
:= Root_Type
(Full_Type
);
2010 -- If this is derived from an untagged private type completed with a
2011 -- tagged type, it does not have a full view, so we use the primitive
2012 -- operations of the private type. This check should no longer be
2013 -- necessary when these types receive their full views ???
2015 if Is_Private_Type
(Typ
)
2016 and then not Is_Tagged_Type
(Typ
)
2017 and then not Is_Controlled
(Typ
)
2018 and then Is_Derived_Type
(Typ
)
2019 and then No
(Full_View
(Typ
))
2021 Prim
:= First_Elmt
(Collect_Primitive_Operations
(Typ
));
2023 Prim
:= First_Elmt
(Primitive_Operations
(Full_Type
));
2027 Eq_Op
:= Node
(Prim
);
2028 exit when Chars
(Eq_Op
) = Name_Op_Eq
2029 and then Etype
(First_Formal
(Eq_Op
)) =
2030 Etype
(Next_Formal
(First_Formal
(Eq_Op
)))
2031 and then Base_Type
(Etype
(Eq_Op
)) = Standard_Boolean
;
2033 pragma Assert
(Present
(Prim
));
2036 Eq_Op
:= Node
(Prim
);
2039 Make_Function_Call
(Loc
,
2040 Name
=> New_Reference_To
(Eq_Op
, Loc
),
2041 Parameter_Associations
=>
2043 (Unchecked_Convert_To
(Etype
(First_Formal
(Eq_Op
)), Lhs
),
2044 Unchecked_Convert_To
(Etype
(First_Formal
(Eq_Op
)), Rhs
)));
2046 elsif Is_Record_Type
(Full_Type
) then
2047 Eq_Op
:= TSS
(Full_Type
, TSS_Composite_Equality
);
2049 if Present
(Eq_Op
) then
2050 if Etype
(First_Formal
(Eq_Op
)) /= Full_Type
then
2052 -- Inherited equality from parent type. Convert the actuals to
2053 -- match signature of operation.
2056 T
: constant Entity_Id
:= Etype
(First_Formal
(Eq_Op
));
2060 Make_Function_Call
(Loc
,
2061 Name
=> New_Reference_To
(Eq_Op
, Loc
),
2062 Parameter_Associations
=>
2063 New_List
(OK_Convert_To
(T
, Lhs
),
2064 OK_Convert_To
(T
, Rhs
)));
2068 -- Comparison between Unchecked_Union components
2070 if Is_Unchecked_Union
(Full_Type
) then
2072 Lhs_Type
: Node_Id
:= Full_Type
;
2073 Rhs_Type
: Node_Id
:= Full_Type
;
2074 Lhs_Discr_Val
: Node_Id
;
2075 Rhs_Discr_Val
: Node_Id
;
2080 if Nkind
(Lhs
) = N_Selected_Component
then
2081 Lhs_Type
:= Etype
(Entity
(Selector_Name
(Lhs
)));
2086 if Nkind
(Rhs
) = N_Selected_Component
then
2087 Rhs_Type
:= Etype
(Entity
(Selector_Name
(Rhs
)));
2090 -- Lhs of the composite equality
2092 if Is_Constrained
(Lhs_Type
) then
2094 -- Since the enclosing record type can never be an
2095 -- Unchecked_Union (this code is executed for records
2096 -- that do not have variants), we may reference its
2099 if Nkind
(Lhs
) = N_Selected_Component
2100 and then Has_Per_Object_Constraint
(
2101 Entity
(Selector_Name
(Lhs
)))
2104 Make_Selected_Component
(Loc
,
2105 Prefix
=> Prefix
(Lhs
),
2108 Get_Discriminant_Value
(
2109 First_Discriminant
(Lhs_Type
),
2111 Stored_Constraint
(Lhs_Type
))));
2114 Lhs_Discr_Val
:= New_Copy
(
2115 Get_Discriminant_Value
(
2116 First_Discriminant
(Lhs_Type
),
2118 Stored_Constraint
(Lhs_Type
)));
2122 -- It is not possible to infer the discriminant since
2123 -- the subtype is not constrained.
2126 Make_Raise_Program_Error
(Loc
,
2127 Reason
=> PE_Unchecked_Union_Restriction
);
2130 -- Rhs of the composite equality
2132 if Is_Constrained
(Rhs_Type
) then
2133 if Nkind
(Rhs
) = N_Selected_Component
2134 and then Has_Per_Object_Constraint
(
2135 Entity
(Selector_Name
(Rhs
)))
2138 Make_Selected_Component
(Loc
,
2139 Prefix
=> Prefix
(Rhs
),
2142 Get_Discriminant_Value
(
2143 First_Discriminant
(Rhs_Type
),
2145 Stored_Constraint
(Rhs_Type
))));
2148 Rhs_Discr_Val
:= New_Copy
(
2149 Get_Discriminant_Value
(
2150 First_Discriminant
(Rhs_Type
),
2152 Stored_Constraint
(Rhs_Type
)));
2157 Make_Raise_Program_Error
(Loc
,
2158 Reason
=> PE_Unchecked_Union_Restriction
);
2161 -- Call the TSS equality function with the inferred
2162 -- discriminant values.
2165 Make_Function_Call
(Loc
,
2166 Name
=> New_Reference_To
(Eq_Op
, Loc
),
2167 Parameter_Associations
=> New_List
(
2175 -- Shouldn't this be an else, we can't fall through the above
2179 Make_Function_Call
(Loc
,
2180 Name
=> New_Reference_To
(Eq_Op
, Loc
),
2181 Parameter_Associations
=> New_List
(Lhs
, Rhs
));
2185 return Expand_Record_Equality
(Nod
, Full_Type
, Lhs
, Rhs
, Bodies
);
2189 -- It can be a simple record or the full view of a scalar private
2191 return Make_Op_Eq
(Loc
, Left_Opnd
=> Lhs
, Right_Opnd
=> Rhs
);
2193 end Expand_Composite_Equality
;
2195 ------------------------
2196 -- Expand_Concatenate --
2197 ------------------------
2199 procedure Expand_Concatenate
(Cnode
: Node_Id
; Opnds
: List_Id
) is
2200 Loc
: constant Source_Ptr
:= Sloc
(Cnode
);
2202 Atyp
: constant Entity_Id
:= Base_Type
(Etype
(Cnode
));
2203 -- Result type of concatenation
2205 Ctyp
: constant Entity_Id
:= Base_Type
(Component_Type
(Etype
(Cnode
)));
2206 -- Component type. Elements of this component type can appear as one
2207 -- of the operands of concatenation as well as arrays.
2209 Istyp
: constant Entity_Id
:= Etype
(First_Index
(Atyp
));
2212 Ityp
: constant Entity_Id
:= Base_Type
(Istyp
);
2213 -- Index type. This is the base type of the index subtype, and is used
2214 -- for all computed bounds (which may be out of range of Istyp in the
2215 -- case of null ranges).
2218 -- This is the type we use to do arithmetic to compute the bounds and
2219 -- lengths of operands. The choice of this type is a little subtle and
2220 -- is discussed in a separate section at the start of the body code.
2222 Concatenation_Error
: exception;
2223 -- Raised if concatenation is sure to raise a CE
2225 Result_May_Be_Null
: Boolean := True;
2226 -- Reset to False if at least one operand is encountered which is known
2227 -- at compile time to be non-null. Used for handling the special case
2228 -- of setting the high bound to the last operand high bound for a null
2229 -- result, thus ensuring a proper high bound in the super-flat case.
2231 N
: constant Nat
:= List_Length
(Opnds
);
2232 -- Number of concatenation operands including possibly null operands
2235 -- Number of operands excluding any known to be null, except that the
2236 -- last operand is always retained, in case it provides the bounds for
2240 -- Current operand being processed in the loop through operands. After
2241 -- this loop is complete, always contains the last operand (which is not
2242 -- the same as Operands (NN), since null operands are skipped).
2244 -- Arrays describing the operands, only the first NN entries of each
2245 -- array are set (NN < N when we exclude known null operands).
2247 Is_Fixed_Length
: array (1 .. N
) of Boolean;
2248 -- True if length of corresponding operand known at compile time
2250 Operands
: array (1 .. N
) of Node_Id
;
2251 -- Set to the corresponding entry in the Opnds list (but note that null
2252 -- operands are excluded, so not all entries in the list are stored).
2254 Fixed_Length
: array (1 .. N
) of Uint
;
2255 -- Set to length of operand. Entries in this array are set only if the
2256 -- corresponding entry in Is_Fixed_Length is True.
2258 Opnd_Low_Bound
: array (1 .. N
) of Node_Id
;
2259 -- Set to lower bound of operand. Either an integer literal in the case
2260 -- where the bound is known at compile time, else actual lower bound.
2261 -- The operand low bound is of type Ityp.
2263 Var_Length
: array (1 .. N
) of Entity_Id
;
2264 -- Set to an entity of type Natural that contains the length of an
2265 -- operand whose length is not known at compile time. Entries in this
2266 -- array are set only if the corresponding entry in Is_Fixed_Length
2267 -- is False. The entity is of type Artyp.
2269 Aggr_Length
: array (0 .. N
) of Node_Id
;
2270 -- The J'th entry in an expression node that represents the total length
2271 -- of operands 1 through J. It is either an integer literal node, or a
2272 -- reference to a constant entity with the right value, so it is fine
2273 -- to just do a Copy_Node to get an appropriate copy. The extra zero'th
2274 -- entry always is set to zero. The length is of type Artyp.
2276 Low_Bound
: Node_Id
;
2277 -- A tree node representing the low bound of the result (of type Ityp).
2278 -- This is either an integer literal node, or an identifier reference to
2279 -- a constant entity initialized to the appropriate value.
2281 Last_Opnd_High_Bound
: Node_Id
;
2282 -- A tree node representing the high bound of the last operand. This
2283 -- need only be set if the result could be null. It is used for the
2284 -- special case of setting the right high bound for a null result.
2285 -- This is of type Ityp.
2287 High_Bound
: Node_Id
;
2288 -- A tree node representing the high bound of the result (of type Ityp)
2291 -- Result of the concatenation (of type Ityp)
2293 Actions
: constant List_Id
:= New_List
;
2294 -- Collect actions to be inserted if Save_Space is False
2296 Save_Space
: Boolean;
2297 pragma Warnings
(Off
, Save_Space
);
2298 -- Set to True if we are saving generated code space by calling routines
2299 -- in packages System.Concat_n.
2301 Known_Non_Null_Operand_Seen
: Boolean;
2302 -- Set True during generation of the assignements of operands into
2303 -- result once an operand known to be non-null has been seen.
2305 function Make_Artyp_Literal
(Val
: Nat
) return Node_Id
;
2306 -- This function makes an N_Integer_Literal node that is returned in
2307 -- analyzed form with the type set to Artyp. Importantly this literal
2308 -- is not flagged as static, so that if we do computations with it that
2309 -- result in statically detected out of range conditions, we will not
2310 -- generate error messages but instead warning messages.
2312 function To_Artyp
(X
: Node_Id
) return Node_Id
;
2313 -- Given a node of type Ityp, returns the corresponding value of type
2314 -- Artyp. For non-enumeration types, this is a plain integer conversion.
2315 -- For enum types, the Pos of the value is returned.
2317 function To_Ityp
(X
: Node_Id
) return Node_Id
;
2318 -- The inverse function (uses Val in the case of enumeration types)
2320 ------------------------
2321 -- Make_Artyp_Literal --
2322 ------------------------
2324 function Make_Artyp_Literal
(Val
: Nat
) return Node_Id
is
2325 Result
: constant Node_Id
:= Make_Integer_Literal
(Loc
, Val
);
2327 Set_Etype
(Result
, Artyp
);
2328 Set_Analyzed
(Result
, True);
2329 Set_Is_Static_Expression
(Result
, False);
2331 end Make_Artyp_Literal
;
2337 function To_Artyp
(X
: Node_Id
) return Node_Id
is
2339 if Ityp
= Base_Type
(Artyp
) then
2342 elsif Is_Enumeration_Type
(Ityp
) then
2344 Make_Attribute_Reference
(Loc
,
2345 Prefix
=> New_Occurrence_Of
(Ityp
, Loc
),
2346 Attribute_Name
=> Name_Pos
,
2347 Expressions
=> New_List
(X
));
2350 return Convert_To
(Artyp
, X
);
2358 function To_Ityp
(X
: Node_Id
) return Node_Id
is
2360 if Is_Enumeration_Type
(Ityp
) then
2362 Make_Attribute_Reference
(Loc
,
2363 Prefix
=> New_Occurrence_Of
(Ityp
, Loc
),
2364 Attribute_Name
=> Name_Val
,
2365 Expressions
=> New_List
(X
));
2367 -- Case where we will do a type conversion
2370 if Ityp
= Base_Type
(Artyp
) then
2373 return Convert_To
(Ityp
, X
);
2378 -- Local Declarations
2380 Opnd_Typ
: Entity_Id
;
2388 -- Choose an appropriate computational type
2390 -- We will be doing calculations of lengths and bounds in this routine
2391 -- and computing one from the other in some cases, e.g. getting the high
2392 -- bound by adding the length-1 to the low bound.
2394 -- We can't just use the index type, or even its base type for this
2395 -- purpose for two reasons. First it might be an enumeration type which
2396 -- is not suitable fo computations of any kind, and second it may simply
2397 -- not have enough range. For example if the index type is -128..+127
2398 -- then lengths can be up to 256, which is out of range of the type.
2400 -- For enumeration types, we can simply use Standard_Integer, this is
2401 -- sufficient since the actual number of enumeration literals cannot
2402 -- possibly exceed the range of integer (remember we will be doing the
2403 -- arithmetic with POS values, not representation values).
2405 if Is_Enumeration_Type
(Ityp
) then
2406 Artyp
:= Standard_Integer
;
2408 -- If index type is Positive, we use the standard unsigned type, to give
2409 -- more room on the top of the range, obviating the need for an overflow
2410 -- check when creating the upper bound. This is needed to avoid junk
2411 -- overflow checks in the common case of String types.
2413 -- ??? Disabled for now
2415 -- elsif Istyp = Standard_Positive then
2416 -- Artyp := Standard_Unsigned;
2418 -- For modular types, we use a 32-bit modular type for types whose size
2419 -- is in the range 1-31 bits. For 32-bit unsigned types, we use the
2420 -- identity type, and for larger unsigned types we use 64-bits.
2422 elsif Is_Modular_Integer_Type
(Ityp
) then
2423 if RM_Size
(Ityp
) < RM_Size
(Standard_Unsigned
) then
2424 Artyp
:= Standard_Unsigned
;
2425 elsif RM_Size
(Ityp
) = RM_Size
(Standard_Unsigned
) then
2428 Artyp
:= RTE
(RE_Long_Long_Unsigned
);
2431 -- Similar treatment for signed types
2434 if RM_Size
(Ityp
) < RM_Size
(Standard_Integer
) then
2435 Artyp
:= Standard_Integer
;
2436 elsif RM_Size
(Ityp
) = RM_Size
(Standard_Integer
) then
2439 Artyp
:= Standard_Long_Long_Integer
;
2443 -- Supply dummy entry at start of length array
2445 Aggr_Length
(0) := Make_Artyp_Literal
(0);
2447 -- Go through operands setting up the above arrays
2451 Opnd
:= Remove_Head
(Opnds
);
2452 Opnd_Typ
:= Etype
(Opnd
);
2454 -- The parent got messed up when we put the operands in a list,
2455 -- so now put back the proper parent for the saved operand.
2457 Set_Parent
(Opnd
, Parent
(Cnode
));
2459 -- Set will be True when we have setup one entry in the array
2463 -- Singleton element (or character literal) case
2465 if Base_Type
(Opnd_Typ
) = Ctyp
then
2467 Operands
(NN
) := Opnd
;
2468 Is_Fixed_Length
(NN
) := True;
2469 Fixed_Length
(NN
) := Uint_1
;
2470 Result_May_Be_Null
:= False;
2472 -- Set low bound of operand (no need to set Last_Opnd_High_Bound
2473 -- since we know that the result cannot be null).
2475 Opnd_Low_Bound
(NN
) :=
2476 Make_Attribute_Reference
(Loc
,
2477 Prefix
=> New_Reference_To
(Istyp
, Loc
),
2478 Attribute_Name
=> Name_First
);
2482 -- String literal case (can only occur for strings of course)
2484 elsif Nkind
(Opnd
) = N_String_Literal
then
2485 Len
:= String_Literal_Length
(Opnd_Typ
);
2488 Result_May_Be_Null
:= False;
2491 -- Capture last operand high bound if result could be null
2493 if J
= N
and then Result_May_Be_Null
then
2494 Last_Opnd_High_Bound
:=
2497 New_Copy_Tree
(String_Literal_Low_Bound
(Opnd_Typ
)),
2498 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1));
2501 -- Skip null string literal
2503 if J
< N
and then Len
= 0 then
2508 Operands
(NN
) := Opnd
;
2509 Is_Fixed_Length
(NN
) := True;
2511 -- Set length and bounds
2513 Fixed_Length
(NN
) := Len
;
2515 Opnd_Low_Bound
(NN
) :=
2516 New_Copy_Tree
(String_Literal_Low_Bound
(Opnd_Typ
));
2523 -- Check constrained case with known bounds
2525 if Is_Constrained
(Opnd_Typ
) then
2527 Index
: constant Node_Id
:= First_Index
(Opnd_Typ
);
2528 Indx_Typ
: constant Entity_Id
:= Etype
(Index
);
2529 Lo
: constant Node_Id
:= Type_Low_Bound
(Indx_Typ
);
2530 Hi
: constant Node_Id
:= Type_High_Bound
(Indx_Typ
);
2533 -- Fixed length constrained array type with known at compile
2534 -- time bounds is last case of fixed length operand.
2536 if Compile_Time_Known_Value
(Lo
)
2538 Compile_Time_Known_Value
(Hi
)
2541 Loval
: constant Uint
:= Expr_Value
(Lo
);
2542 Hival
: constant Uint
:= Expr_Value
(Hi
);
2543 Len
: constant Uint
:=
2544 UI_Max
(Hival
- Loval
+ 1, Uint_0
);
2548 Result_May_Be_Null
:= False;
2551 -- Capture last operand bound if result could be null
2553 if J
= N
and then Result_May_Be_Null
then
2554 Last_Opnd_High_Bound
:=
2556 Make_Integer_Literal
(Loc
,
2557 Intval
=> Expr_Value
(Hi
)));
2560 -- Exclude null length case unless last operand
2562 if J
< N
and then Len
= 0 then
2567 Operands
(NN
) := Opnd
;
2568 Is_Fixed_Length
(NN
) := True;
2569 Fixed_Length
(NN
) := Len
;
2571 Opnd_Low_Bound
(NN
) := To_Ityp
(
2572 Make_Integer_Literal
(Loc
,
2573 Intval
=> Expr_Value
(Lo
)));
2581 -- All cases where the length is not known at compile time, or the
2582 -- special case of an operand which is known to be null but has a
2583 -- lower bound other than 1 or is other than a string type.
2588 -- Capture operand bounds
2590 Opnd_Low_Bound
(NN
) :=
2591 Make_Attribute_Reference
(Loc
,
2593 Duplicate_Subexpr
(Opnd
, Name_Req
=> True),
2594 Attribute_Name
=> Name_First
);
2596 if J
= N
and Result_May_Be_Null
then
2597 Last_Opnd_High_Bound
:=
2599 Make_Attribute_Reference
(Loc
,
2601 Duplicate_Subexpr
(Opnd
, Name_Req
=> True),
2602 Attribute_Name
=> Name_Last
));
2605 -- Capture length of operand in entity
2607 Operands
(NN
) := Opnd
;
2608 Is_Fixed_Length
(NN
) := False;
2610 Var_Length
(NN
) := Make_Temporary
(Loc
, 'L');
2613 Make_Object_Declaration
(Loc
,
2614 Defining_Identifier
=> Var_Length
(NN
),
2615 Constant_Present
=> True,
2617 Object_Definition
=>
2618 New_Occurrence_Of
(Artyp
, Loc
),
2621 Make_Attribute_Reference
(Loc
,
2623 Duplicate_Subexpr
(Opnd
, Name_Req
=> True),
2624 Attribute_Name
=> Name_Length
)));
2628 -- Set next entry in aggregate length array
2630 -- For first entry, make either integer literal for fixed length
2631 -- or a reference to the saved length for variable length.
2634 if Is_Fixed_Length
(1) then
2636 Make_Integer_Literal
(Loc
,
2637 Intval
=> Fixed_Length
(1));
2640 New_Reference_To
(Var_Length
(1), Loc
);
2643 -- If entry is fixed length and only fixed lengths so far, make
2644 -- appropriate new integer literal adding new length.
2646 elsif Is_Fixed_Length
(NN
)
2647 and then Nkind
(Aggr_Length
(NN
- 1)) = N_Integer_Literal
2650 Make_Integer_Literal
(Loc
,
2651 Intval
=> Fixed_Length
(NN
) + Intval
(Aggr_Length
(NN
- 1)));
2653 -- All other cases, construct an addition node for the length and
2654 -- create an entity initialized to this length.
2657 Ent
:= Make_Temporary
(Loc
, 'L');
2659 if Is_Fixed_Length
(NN
) then
2660 Clen
:= Make_Integer_Literal
(Loc
, Fixed_Length
(NN
));
2662 Clen
:= New_Reference_To
(Var_Length
(NN
), Loc
);
2666 Make_Object_Declaration
(Loc
,
2667 Defining_Identifier
=> Ent
,
2668 Constant_Present
=> True,
2670 Object_Definition
=>
2671 New_Occurrence_Of
(Artyp
, Loc
),
2675 Left_Opnd
=> New_Copy
(Aggr_Length
(NN
- 1)),
2676 Right_Opnd
=> Clen
)));
2678 Aggr_Length
(NN
) := Make_Identifier
(Loc
, Chars
=> Chars
(Ent
));
2685 -- If we have only skipped null operands, return the last operand
2692 -- If we have only one non-null operand, return it and we are done.
2693 -- There is one case in which this cannot be done, and that is when
2694 -- the sole operand is of the element type, in which case it must be
2695 -- converted to an array, and the easiest way of doing that is to go
2696 -- through the normal general circuit.
2699 and then Base_Type
(Etype
(Operands
(1))) /= Ctyp
2701 Result
:= Operands
(1);
2705 -- Cases where we have a real concatenation
2707 -- Next step is to find the low bound for the result array that we
2708 -- will allocate. The rules for this are in (RM 4.5.6(5-7)).
2710 -- If the ultimate ancestor of the index subtype is a constrained array
2711 -- definition, then the lower bound is that of the index subtype as
2712 -- specified by (RM 4.5.3(6)).
2714 -- The right test here is to go to the root type, and then the ultimate
2715 -- ancestor is the first subtype of this root type.
2717 if Is_Constrained
(First_Subtype
(Root_Type
(Atyp
))) then
2719 Make_Attribute_Reference
(Loc
,
2721 New_Occurrence_Of
(First_Subtype
(Root_Type
(Atyp
)), Loc
),
2722 Attribute_Name
=> Name_First
);
2724 -- If the first operand in the list has known length we know that
2725 -- the lower bound of the result is the lower bound of this operand.
2727 elsif Is_Fixed_Length
(1) then
2728 Low_Bound
:= Opnd_Low_Bound
(1);
2730 -- OK, we don't know the lower bound, we have to build a horrible
2731 -- expression actions node of the form
2733 -- if Cond1'Length /= 0 then
2736 -- if Opnd2'Length /= 0 then
2741 -- The nesting ends either when we hit an operand whose length is known
2742 -- at compile time, or on reaching the last operand, whose low bound we
2743 -- take unconditionally whether or not it is null. It's easiest to do
2744 -- this with a recursive procedure:
2748 function Get_Known_Bound
(J
: Nat
) return Node_Id
;
2749 -- Returns the lower bound determined by operands J .. NN
2751 ---------------------
2752 -- Get_Known_Bound --
2753 ---------------------
2755 function Get_Known_Bound
(J
: Nat
) return Node_Id
is
2757 if Is_Fixed_Length
(J
) or else J
= NN
then
2758 return New_Copy
(Opnd_Low_Bound
(J
));
2762 Make_Conditional_Expression
(Loc
,
2763 Expressions
=> New_List
(
2766 Left_Opnd
=> New_Reference_To
(Var_Length
(J
), Loc
),
2767 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0)),
2769 New_Copy
(Opnd_Low_Bound
(J
)),
2770 Get_Known_Bound
(J
+ 1)));
2772 end Get_Known_Bound
;
2775 Ent
:= Make_Temporary
(Loc
, 'L');
2778 Make_Object_Declaration
(Loc
,
2779 Defining_Identifier
=> Ent
,
2780 Constant_Present
=> True,
2781 Object_Definition
=> New_Occurrence_Of
(Ityp
, Loc
),
2782 Expression
=> Get_Known_Bound
(1)));
2784 Low_Bound
:= New_Reference_To
(Ent
, Loc
);
2788 -- Now we can safely compute the upper bound, normally
2789 -- Low_Bound + Length - 1.
2794 Left_Opnd
=> To_Artyp
(New_Copy
(Low_Bound
)),
2796 Make_Op_Subtract
(Loc
,
2797 Left_Opnd
=> New_Copy
(Aggr_Length
(NN
)),
2798 Right_Opnd
=> Make_Artyp_Literal
(1))));
2800 -- Note that calculation of the high bound may cause overflow in some
2801 -- very weird cases, so in the general case we need an overflow check on
2802 -- the high bound. We can avoid this for the common case of string types
2803 -- and other types whose index is Positive, since we chose a wider range
2804 -- for the arithmetic type.
2806 if Istyp
/= Standard_Positive
then
2807 Activate_Overflow_Check
(High_Bound
);
2810 -- Handle the exceptional case where the result is null, in which case
2811 -- case the bounds come from the last operand (so that we get the proper
2812 -- bounds if the last operand is super-flat).
2814 if Result_May_Be_Null
then
2816 Make_Conditional_Expression
(Loc
,
2817 Expressions
=> New_List
(
2819 Left_Opnd
=> New_Copy
(Aggr_Length
(NN
)),
2820 Right_Opnd
=> Make_Artyp_Literal
(0)),
2821 Last_Opnd_High_Bound
,
2825 -- Here is where we insert the saved up actions
2827 Insert_Actions
(Cnode
, Actions
, Suppress
=> All_Checks
);
2829 -- Now we construct an array object with appropriate bounds. We mark
2830 -- the target as internal to prevent useless initialization when
2831 -- Initialize_Scalars is enabled.
2833 Ent
:= Make_Temporary
(Loc
, 'S');
2834 Set_Is_Internal
(Ent
);
2836 -- If the bound is statically known to be out of range, we do not want
2837 -- to abort, we want a warning and a runtime constraint error. Note that
2838 -- we have arranged that the result will not be treated as a static
2839 -- constant, so we won't get an illegality during this insertion.
2841 Insert_Action
(Cnode
,
2842 Make_Object_Declaration
(Loc
,
2843 Defining_Identifier
=> Ent
,
2844 Object_Definition
=>
2845 Make_Subtype_Indication
(Loc
,
2846 Subtype_Mark
=> New_Occurrence_Of
(Atyp
, Loc
),
2848 Make_Index_Or_Discriminant_Constraint
(Loc
,
2849 Constraints
=> New_List
(
2851 Low_Bound
=> Low_Bound
,
2852 High_Bound
=> High_Bound
))))),
2853 Suppress
=> All_Checks
);
2855 -- If the result of the concatenation appears as the initializing
2856 -- expression of an object declaration, we can just rename the
2857 -- result, rather than copying it.
2859 Set_OK_To_Rename
(Ent
);
2861 -- Catch the static out of range case now
2863 if Raises_Constraint_Error
(High_Bound
) then
2864 raise Concatenation_Error
;
2867 -- Now we will generate the assignments to do the actual concatenation
2869 -- There is one case in which we will not do this, namely when all the
2870 -- following conditions are met:
2872 -- The result type is Standard.String
2874 -- There are nine or fewer retained (non-null) operands
2876 -- The optimization level is -O0
2878 -- The corresponding System.Concat_n.Str_Concat_n routine is
2879 -- available in the run time.
2881 -- The debug flag gnatd.c is not set
2883 -- If all these conditions are met then we generate a call to the
2884 -- relevant concatenation routine. The purpose of this is to avoid
2885 -- undesirable code bloat at -O0.
2887 if Atyp
= Standard_String
2888 and then NN
in 2 .. 9
2889 and then (Opt
.Optimization_Level
= 0 or else Debug_Flag_Dot_CC
)
2890 and then not Debug_Flag_Dot_C
2893 RR
: constant array (Nat
range 2 .. 9) of RE_Id
:=
2904 if RTE_Available
(RR
(NN
)) then
2906 Opnds
: constant List_Id
:=
2907 New_List
(New_Occurrence_Of
(Ent
, Loc
));
2910 for J
in 1 .. NN
loop
2911 if Is_List_Member
(Operands
(J
)) then
2912 Remove
(Operands
(J
));
2915 if Base_Type
(Etype
(Operands
(J
))) = Ctyp
then
2917 Make_Aggregate
(Loc
,
2918 Component_Associations
=> New_List
(
2919 Make_Component_Association
(Loc
,
2920 Choices
=> New_List
(
2921 Make_Integer_Literal
(Loc
, 1)),
2922 Expression
=> Operands
(J
)))));
2925 Append_To
(Opnds
, Operands
(J
));
2929 Insert_Action
(Cnode
,
2930 Make_Procedure_Call_Statement
(Loc
,
2931 Name
=> New_Reference_To
(RTE
(RR
(NN
)), Loc
),
2932 Parameter_Associations
=> Opnds
));
2934 Result
:= New_Reference_To
(Ent
, Loc
);
2941 -- Not special case so generate the assignments
2943 Known_Non_Null_Operand_Seen
:= False;
2945 for J
in 1 .. NN
loop
2947 Lo
: constant Node_Id
:=
2949 Left_Opnd
=> To_Artyp
(New_Copy
(Low_Bound
)),
2950 Right_Opnd
=> Aggr_Length
(J
- 1));
2952 Hi
: constant Node_Id
:=
2954 Left_Opnd
=> To_Artyp
(New_Copy
(Low_Bound
)),
2956 Make_Op_Subtract
(Loc
,
2957 Left_Opnd
=> Aggr_Length
(J
),
2958 Right_Opnd
=> Make_Artyp_Literal
(1)));
2961 -- Singleton case, simple assignment
2963 if Base_Type
(Etype
(Operands
(J
))) = Ctyp
then
2964 Known_Non_Null_Operand_Seen
:= True;
2965 Insert_Action
(Cnode
,
2966 Make_Assignment_Statement
(Loc
,
2968 Make_Indexed_Component
(Loc
,
2969 Prefix
=> New_Occurrence_Of
(Ent
, Loc
),
2970 Expressions
=> New_List
(To_Ityp
(Lo
))),
2971 Expression
=> Operands
(J
)),
2972 Suppress
=> All_Checks
);
2974 -- Array case, slice assignment, skipped when argument is fixed
2975 -- length and known to be null.
2977 elsif (not Is_Fixed_Length
(J
)) or else (Fixed_Length
(J
) > 0) then
2980 Make_Assignment_Statement
(Loc
,
2984 New_Occurrence_Of
(Ent
, Loc
),
2987 Low_Bound
=> To_Ityp
(Lo
),
2988 High_Bound
=> To_Ityp
(Hi
))),
2989 Expression
=> Operands
(J
));
2991 if Is_Fixed_Length
(J
) then
2992 Known_Non_Null_Operand_Seen
:= True;
2994 elsif not Known_Non_Null_Operand_Seen
then
2996 -- Here if operand length is not statically known and no
2997 -- operand known to be non-null has been processed yet.
2998 -- If operand length is 0, we do not need to perform the
2999 -- assignment, and we must avoid the evaluation of the
3000 -- high bound of the slice, since it may underflow if the
3001 -- low bound is Ityp'First.
3004 Make_Implicit_If_Statement
(Cnode
,
3008 New_Occurrence_Of
(Var_Length
(J
), Loc
),
3009 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0)),
3014 Insert_Action
(Cnode
, Assign
, Suppress
=> All_Checks
);
3020 -- Finally we build the result, which is a reference to the array object
3022 Result
:= New_Reference_To
(Ent
, Loc
);
3025 Rewrite
(Cnode
, Result
);
3026 Analyze_And_Resolve
(Cnode
, Atyp
);
3029 when Concatenation_Error
=>
3031 -- Kill warning generated for the declaration of the static out of
3032 -- range high bound, and instead generate a Constraint_Error with
3033 -- an appropriate specific message.
3035 Kill_Dead_Code
(Declaration_Node
(Entity
(High_Bound
)));
3036 Apply_Compile_Time_Constraint_Error
3038 Msg
=> "concatenation result upper bound out of range?",
3039 Reason
=> CE_Range_Check_Failed
);
3040 -- Set_Etype (Cnode, Atyp);
3041 end Expand_Concatenate
;
3043 ------------------------
3044 -- Expand_N_Allocator --
3045 ------------------------
3047 procedure Expand_N_Allocator
(N
: Node_Id
) is
3048 PtrT
: constant Entity_Id
:= Etype
(N
);
3049 Dtyp
: constant Entity_Id
:= Available_View
(Designated_Type
(PtrT
));
3050 Etyp
: constant Entity_Id
:= Etype
(Expression
(N
));
3051 Loc
: constant Source_Ptr
:= Sloc
(N
);
3056 procedure Complete_Coextension_Finalization
;
3057 -- Generate finalization calls for all nested coextensions of N. This
3058 -- routine may allocate list controllers if necessary.
3060 procedure Rewrite_Coextension
(N
: Node_Id
);
3061 -- Static coextensions have the same lifetime as the entity they
3062 -- constrain. Such occurrences can be rewritten as aliased objects
3063 -- and their unrestricted access used instead of the coextension.
3065 function Size_In_Storage_Elements
(E
: Entity_Id
) return Node_Id
;
3066 -- Given a constrained array type E, returns a node representing the
3067 -- code to compute the size in storage elements for the given type.
3068 -- This is done without using the attribute (which malfunctions for
3071 ---------------------------------------
3072 -- Complete_Coextension_Finalization --
3073 ---------------------------------------
3075 procedure Complete_Coextension_Finalization
is
3077 Coext_Elmt
: Elmt_Id
;
3081 function Inside_A_Return_Statement
(N
: Node_Id
) return Boolean;
3082 -- Determine whether node N is part of a return statement
3084 function Needs_Initialization_Call
(N
: Node_Id
) return Boolean;
3085 -- Determine whether node N is a subtype indicator allocator which
3086 -- acts a coextension. Such coextensions need initialization.
3088 -------------------------------
3089 -- Inside_A_Return_Statement --
3090 -------------------------------
3092 function Inside_A_Return_Statement
(N
: Node_Id
) return Boolean is
3097 while Present
(P
) loop
3099 (P
, N_Extended_Return_Statement
, N_Simple_Return_Statement
)
3103 -- Stop the traversal when we reach a subprogram body
3105 elsif Nkind
(P
) = N_Subprogram_Body
then
3113 end Inside_A_Return_Statement
;
3115 -------------------------------
3116 -- Needs_Initialization_Call --
3117 -------------------------------
3119 function Needs_Initialization_Call
(N
: Node_Id
) return Boolean is
3123 if Nkind
(N
) = N_Explicit_Dereference
3124 and then Nkind
(Prefix
(N
)) = N_Identifier
3125 and then Nkind
(Parent
(Entity
(Prefix
(N
)))) =
3126 N_Object_Declaration
3128 Obj_Decl
:= Parent
(Entity
(Prefix
(N
)));
3131 Present
(Expression
(Obj_Decl
))
3132 and then Nkind
(Expression
(Obj_Decl
)) = N_Allocator
3133 and then Nkind
(Expression
(Expression
(Obj_Decl
))) /=
3134 N_Qualified_Expression
;
3138 end Needs_Initialization_Call
;
3140 -- Start of processing for Complete_Coextension_Finalization
3143 -- When a coextension root is inside a return statement, we need to
3144 -- use the finalization chain of the function's scope. This does not
3145 -- apply for controlled named access types because in those cases we
3146 -- can use the finalization chain of the type itself.
3148 if Inside_A_Return_Statement
(N
)
3150 (Ekind
(PtrT
) = E_Anonymous_Access_Type
3152 (Ekind
(PtrT
) = E_Access_Type
3153 and then No
(Associated_Final_Chain
(PtrT
))))
3157 Outer_S
: Entity_Id
;
3162 while Present
(S
) and then S
/= Standard_Standard
loop
3163 if Ekind
(S
) = E_Function
then
3164 Outer_S
:= Scope
(S
);
3166 -- Retrieve the declaration of the body
3171 (Corresponding_Body
(Parent
(Parent
(S
)))));
3178 -- Push the scope of the function body since we are inserting
3179 -- the list before the body, but we are currently in the body
3180 -- itself. Override the finalization list of PtrT since the
3181 -- finalization context is now different.
3183 Push_Scope
(Outer_S
);
3184 Build_Final_List
(Decl
, PtrT
);
3188 -- The root allocator may not be controlled, but it still needs a
3189 -- finalization list for all nested coextensions.
3191 elsif No
(Associated_Final_Chain
(PtrT
)) then
3192 Build_Final_List
(N
, PtrT
);
3196 Make_Selected_Component
(Loc
,
3198 New_Reference_To
(Associated_Final_Chain
(PtrT
), Loc
),
3200 Make_Identifier
(Loc
, Name_F
));
3202 Coext_Elmt
:= First_Elmt
(Coextensions
(N
));
3203 while Present
(Coext_Elmt
) loop
3204 Coext
:= Node
(Coext_Elmt
);
3209 if Nkind
(Coext
) = N_Identifier
then
3211 Make_Unchecked_Type_Conversion
(Loc
,
3212 Subtype_Mark
=> New_Reference_To
(Etype
(Coext
), Loc
),
3214 Make_Explicit_Dereference
(Loc
,
3215 Prefix
=> New_Copy_Tree
(Coext
)));
3217 Ref
:= New_Copy_Tree
(Coext
);
3220 -- No initialization call if not allowed
3222 Check_Restriction
(No_Default_Initialization
, N
);
3224 if not Restriction_Active
(No_Default_Initialization
) then
3228 -- attach_to_final_list (Ref, Flist, 2)
3230 if Needs_Initialization_Call
(Coext
) then
3234 Typ
=> Etype
(Coext
),
3236 With_Attach
=> Make_Integer_Literal
(Loc
, Uint_2
)));
3239 -- attach_to_final_list (Ref, Flist, 2)
3245 Flist_Ref
=> New_Copy_Tree
(Flist
),
3246 With_Attach
=> Make_Integer_Literal
(Loc
, Uint_2
)));
3250 Next_Elmt
(Coext_Elmt
);
3252 end Complete_Coextension_Finalization
;
3254 -------------------------
3255 -- Rewrite_Coextension --
3256 -------------------------
3258 procedure Rewrite_Coextension
(N
: Node_Id
) is
3259 Temp
: constant Node_Id
:= Make_Temporary
(Loc
, 'C');
3262 -- Cnn : aliased Etyp;
3264 Decl
: constant Node_Id
:=
3265 Make_Object_Declaration
(Loc
,
3266 Defining_Identifier
=> Temp
,
3267 Aliased_Present
=> True,
3268 Object_Definition
=>
3269 New_Occurrence_Of
(Etyp
, Loc
));
3273 if Nkind
(Expression
(N
)) = N_Qualified_Expression
then
3274 Set_Expression
(Decl
, Expression
(Expression
(N
)));
3277 -- Find the proper insertion node for the declaration
3280 while Present
(Nod
) loop
3281 exit when Nkind
(Nod
) in N_Statement_Other_Than_Procedure_Call
3282 or else Nkind
(Nod
) = N_Procedure_Call_Statement
3283 or else Nkind
(Nod
) in N_Declaration
;
3284 Nod
:= Parent
(Nod
);
3287 Insert_Before
(Nod
, Decl
);
3291 Make_Attribute_Reference
(Loc
,
3292 Prefix
=> New_Occurrence_Of
(Temp
, Loc
),
3293 Attribute_Name
=> Name_Unrestricted_Access
));
3295 Analyze_And_Resolve
(N
, PtrT
);
3296 end Rewrite_Coextension
;
3298 ------------------------------
3299 -- Size_In_Storage_Elements --
3300 ------------------------------
3302 function Size_In_Storage_Elements
(E
: Entity_Id
) return Node_Id
is
3304 -- Logically this just returns E'Max_Size_In_Storage_Elements.
3305 -- However, the reason for the existence of this function is
3306 -- to construct a test for sizes too large, which means near the
3307 -- 32-bit limit on a 32-bit machine, and precisely the trouble
3308 -- is that we get overflows when sizes are greater than 2**31.
3310 -- So what we end up doing for array types is to use the expression:
3312 -- number-of-elements * component_type'Max_Size_In_Storage_Elements
3314 -- which avoids this problem. All this is a big bogus, but it does
3315 -- mean we catch common cases of trying to allocate arrays that
3316 -- are too large, and which in the absence of a check results in
3317 -- undetected chaos ???
3324 for J
in 1 .. Number_Dimensions
(E
) loop
3326 Make_Attribute_Reference
(Loc
,
3327 Prefix
=> New_Occurrence_Of
(E
, Loc
),
3328 Attribute_Name
=> Name_Length
,
3329 Expressions
=> New_List
(
3330 Make_Integer_Literal
(Loc
, J
)));
3337 Make_Op_Multiply
(Loc
,
3344 Make_Op_Multiply
(Loc
,
3347 Make_Attribute_Reference
(Loc
,
3348 Prefix
=> New_Occurrence_Of
(Component_Type
(E
), Loc
),
3349 Attribute_Name
=> Name_Max_Size_In_Storage_Elements
));
3351 end Size_In_Storage_Elements
;
3353 -- Start of processing for Expand_N_Allocator
3356 -- RM E.2.3(22). We enforce that the expected type of an allocator
3357 -- shall not be a remote access-to-class-wide-limited-private type
3359 -- Why is this being done at expansion time, seems clearly wrong ???
3361 Validate_Remote_Access_To_Class_Wide_Type
(N
);
3363 -- Set the Storage Pool
3365 Set_Storage_Pool
(N
, Associated_Storage_Pool
(Root_Type
(PtrT
)));
3367 if Present
(Storage_Pool
(N
)) then
3368 if Is_RTE
(Storage_Pool
(N
), RE_SS_Pool
) then
3369 if VM_Target
= No_VM
then
3370 Set_Procedure_To_Call
(N
, RTE
(RE_SS_Allocate
));
3373 elsif Is_Class_Wide_Type
(Etype
(Storage_Pool
(N
))) then
3374 Set_Procedure_To_Call
(N
, RTE
(RE_Allocate_Any
));
3377 Set_Procedure_To_Call
(N
,
3378 Find_Prim_Op
(Etype
(Storage_Pool
(N
)), Name_Allocate
));
3382 -- Under certain circumstances we can replace an allocator by an access
3383 -- to statically allocated storage. The conditions, as noted in AARM
3384 -- 3.10 (10c) are as follows:
3386 -- Size and initial value is known at compile time
3387 -- Access type is access-to-constant
3389 -- The allocator is not part of a constraint on a record component,
3390 -- because in that case the inserted actions are delayed until the
3391 -- record declaration is fully analyzed, which is too late for the
3392 -- analysis of the rewritten allocator.
3394 if Is_Access_Constant
(PtrT
)
3395 and then Nkind
(Expression
(N
)) = N_Qualified_Expression
3396 and then Compile_Time_Known_Value
(Expression
(Expression
(N
)))
3397 and then Size_Known_At_Compile_Time
(Etype
(Expression
3399 and then not Is_Record_Type
(Current_Scope
)
3401 -- Here we can do the optimization. For the allocator
3405 -- We insert an object declaration
3407 -- Tnn : aliased x := y;
3409 -- and replace the allocator by Tnn'Unrestricted_Access. Tnn is
3410 -- marked as requiring static allocation.
3412 Temp
:= Make_Temporary
(Loc
, 'T', Expression
(Expression
(N
)));
3413 Desig
:= Subtype_Mark
(Expression
(N
));
3415 -- If context is constrained, use constrained subtype directly,
3416 -- so that the constant is not labelled as having a nominally
3417 -- unconstrained subtype.
3419 if Entity
(Desig
) = Base_Type
(Dtyp
) then
3420 Desig
:= New_Occurrence_Of
(Dtyp
, Loc
);
3424 Make_Object_Declaration
(Loc
,
3425 Defining_Identifier
=> Temp
,
3426 Aliased_Present
=> True,
3427 Constant_Present
=> Is_Access_Constant
(PtrT
),
3428 Object_Definition
=> Desig
,
3429 Expression
=> Expression
(Expression
(N
))));
3432 Make_Attribute_Reference
(Loc
,
3433 Prefix
=> New_Occurrence_Of
(Temp
, Loc
),
3434 Attribute_Name
=> Name_Unrestricted_Access
));
3436 Analyze_And_Resolve
(N
, PtrT
);
3438 -- We set the variable as statically allocated, since we don't want
3439 -- it going on the stack of the current procedure!
3441 Set_Is_Statically_Allocated
(Temp
);
3445 -- Same if the allocator is an access discriminant for a local object:
3446 -- instead of an allocator we create a local value and constrain the
3447 -- the enclosing object with the corresponding access attribute.
3449 if Is_Static_Coextension
(N
) then
3450 Rewrite_Coextension
(N
);
3454 -- The current allocator creates an object which may contain nested
3455 -- coextensions. Use the current allocator's finalization list to
3456 -- generate finalization call for all nested coextensions.
3458 if Is_Coextension_Root
(N
) then
3459 Complete_Coextension_Finalization
;
3462 -- Check for size too large, we do this because the back end misses
3463 -- proper checks here and can generate rubbish allocation calls when
3464 -- we are near the limit. We only do this for the 32-bit address case
3465 -- since that is from a practical point of view where we see a problem.
3467 if System_Address_Size
= 32
3468 and then not Storage_Checks_Suppressed
(PtrT
)
3469 and then not Storage_Checks_Suppressed
(Dtyp
)
3470 and then not Storage_Checks_Suppressed
(Etyp
)
3472 -- The check we want to generate should look like
3474 -- if Etyp'Max_Size_In_Storage_Elements > 3.5 gigabytes then
3475 -- raise Storage_Error;
3478 -- where 3.5 gigabytes is a constant large enough to accomodate any
3479 -- reasonable request for. But we can't do it this way because at
3480 -- least at the moment we don't compute this attribute right, and
3481 -- can silently give wrong results when the result gets large. Since
3482 -- this is all about large results, that's bad, so instead we only
3483 -- apply the check for constrained arrays, and manually compute the
3484 -- value of the attribute ???
3486 if Is_Array_Type
(Etyp
) and then Is_Constrained
(Etyp
) then
3488 Make_Raise_Storage_Error
(Loc
,
3491 Left_Opnd
=> Size_In_Storage_Elements
(Etyp
),
3493 Make_Integer_Literal
(Loc
,
3494 Intval
=> Uint_7
* (Uint_2
** 29))),
3495 Reason
=> SE_Object_Too_Large
));
3499 -- Handle case of qualified expression (other than optimization above)
3500 -- First apply constraint checks, because the bounds or discriminants
3501 -- in the aggregate might not match the subtype mark in the allocator.
3503 if Nkind
(Expression
(N
)) = N_Qualified_Expression
then
3504 Apply_Constraint_Check
3505 (Expression
(Expression
(N
)), Etype
(Expression
(N
)));
3507 Expand_Allocator_Expression
(N
);
3511 -- If the allocator is for a type which requires initialization, and
3512 -- there is no initial value (i.e. operand is a subtype indication
3513 -- rather than a qualified expression), then we must generate a call to
3514 -- the initialization routine using an expressions action node:
3516 -- [Pnnn : constant ptr_T := new (T); Init (Pnnn.all,...); Pnnn]
3518 -- Here ptr_T is the pointer type for the allocator, and T is the
3519 -- subtype of the allocator. A special case arises if the designated
3520 -- type of the access type is a task or contains tasks. In this case
3521 -- the call to Init (Temp.all ...) is replaced by code that ensures
3522 -- that tasks get activated (see Exp_Ch9.Build_Task_Allocate_Block
3523 -- for details). In addition, if the type T is a task T, then the
3524 -- first argument to Init must be converted to the task record type.
3527 T
: constant Entity_Id
:= Entity
(Expression
(N
));
3535 Temp_Decl
: Node_Id
;
3536 Temp_Type
: Entity_Id
;
3537 Attach_Level
: Uint
;
3540 if No_Initialization
(N
) then
3543 -- Case of no initialization procedure present
3545 elsif not Has_Non_Null_Base_Init_Proc
(T
) then
3547 -- Case of simple initialization required
3549 if Needs_Simple_Initialization
(T
) then
3550 Check_Restriction
(No_Default_Initialization
, N
);
3551 Rewrite
(Expression
(N
),
3552 Make_Qualified_Expression
(Loc
,
3553 Subtype_Mark
=> New_Occurrence_Of
(T
, Loc
),
3554 Expression
=> Get_Simple_Init_Val
(T
, N
)));
3556 Analyze_And_Resolve
(Expression
(Expression
(N
)), T
);
3557 Analyze_And_Resolve
(Expression
(N
), T
);
3558 Set_Paren_Count
(Expression
(Expression
(N
)), 1);
3559 Expand_N_Allocator
(N
);
3561 -- No initialization required
3567 -- Case of initialization procedure present, must be called
3570 Check_Restriction
(No_Default_Initialization
, N
);
3572 if not Restriction_Active
(No_Default_Initialization
) then
3573 Init
:= Base_Init_Proc
(T
);
3575 Temp
:= Make_Temporary
(Loc
, 'P');
3577 -- Construct argument list for the initialization routine call
3580 Make_Explicit_Dereference
(Loc
,
3581 Prefix
=> New_Reference_To
(Temp
, Loc
));
3582 Set_Assignment_OK
(Arg1
);
3585 -- The initialization procedure expects a specific type. if the
3586 -- context is access to class wide, indicate that the object
3587 -- being allocated has the right specific type.
3589 if Is_Class_Wide_Type
(Dtyp
) then
3590 Arg1
:= Unchecked_Convert_To
(T
, Arg1
);
3593 -- If designated type is a concurrent type or if it is private
3594 -- type whose definition is a concurrent type, the first
3595 -- argument in the Init routine has to be unchecked conversion
3596 -- to the corresponding record type. If the designated type is
3597 -- a derived type, we also convert the argument to its root
3600 if Is_Concurrent_Type
(T
) then
3602 Unchecked_Convert_To
(Corresponding_Record_Type
(T
), Arg1
);
3604 elsif Is_Private_Type
(T
)
3605 and then Present
(Full_View
(T
))
3606 and then Is_Concurrent_Type
(Full_View
(T
))
3609 Unchecked_Convert_To
3610 (Corresponding_Record_Type
(Full_View
(T
)), Arg1
);
3612 elsif Etype
(First_Formal
(Init
)) /= Base_Type
(T
) then
3614 Ftyp
: constant Entity_Id
:= Etype
(First_Formal
(Init
));
3616 Arg1
:= OK_Convert_To
(Etype
(Ftyp
), Arg1
);
3617 Set_Etype
(Arg1
, Ftyp
);
3621 Args
:= New_List
(Arg1
);
3623 -- For the task case, pass the Master_Id of the access type as
3624 -- the value of the _Master parameter, and _Chain as the value
3625 -- of the _Chain parameter (_Chain will be defined as part of
3626 -- the generated code for the allocator).
3628 -- In Ada 2005, the context may be a function that returns an
3629 -- anonymous access type. In that case the Master_Id has been
3630 -- created when expanding the function declaration.
3632 if Has_Task
(T
) then
3633 if No
(Master_Id
(Base_Type
(PtrT
))) then
3635 -- If we have a non-library level task with restriction
3636 -- No_Task_Hierarchy set, then no point in expanding.
3638 if not Is_Library_Level_Entity
(T
)
3639 and then Restriction_Active
(No_Task_Hierarchy
)
3644 -- The designated type was an incomplete type, and the
3645 -- access type did not get expanded. Salvage it now.
3647 if not Restriction_Active
(No_Task_Hierarchy
) then
3648 pragma Assert
(Present
(Parent
(Base_Type
(PtrT
))));
3649 Expand_N_Full_Type_Declaration
3650 (Parent
(Base_Type
(PtrT
)));
3654 -- If the context of the allocator is a declaration or an
3655 -- assignment, we can generate a meaningful image for it,
3656 -- even though subsequent assignments might remove the
3657 -- connection between task and entity. We build this image
3658 -- when the left-hand side is a simple variable, a simple
3659 -- indexed assignment or a simple selected component.
3661 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
3663 Nam
: constant Node_Id
:= Name
(Parent
(N
));
3666 if Is_Entity_Name
(Nam
) then
3668 Build_Task_Image_Decls
3671 (Entity
(Nam
), Sloc
(Nam
)), T
);
3674 (Nam
, N_Indexed_Component
, N_Selected_Component
)
3675 and then Is_Entity_Name
(Prefix
(Nam
))
3678 Build_Task_Image_Decls
3679 (Loc
, Nam
, Etype
(Prefix
(Nam
)));
3681 Decls
:= Build_Task_Image_Decls
(Loc
, T
, T
);
3685 elsif Nkind
(Parent
(N
)) = N_Object_Declaration
then
3687 Build_Task_Image_Decls
3688 (Loc
, Defining_Identifier
(Parent
(N
)), T
);
3691 Decls
:= Build_Task_Image_Decls
(Loc
, T
, T
);
3694 if Restriction_Active
(No_Task_Hierarchy
) then
3695 -- 3 is System.Tasking.Library_Task_Level
3696 Append_To
(Args
, Make_Integer_Literal
(Loc
, 3));
3700 (Master_Id
(Base_Type
(Root_Type
(PtrT
))), Loc
));
3703 Append_To
(Args
, Make_Identifier
(Loc
, Name_uChain
));
3705 Decl
:= Last
(Decls
);
3707 New_Occurrence_Of
(Defining_Identifier
(Decl
), Loc
));
3709 -- Has_Task is false, Decls not used
3715 -- Add discriminants if discriminated type
3718 Dis
: Boolean := False;
3722 if Has_Discriminants
(T
) then
3726 elsif Is_Private_Type
(T
)
3727 and then Present
(Full_View
(T
))
3728 and then Has_Discriminants
(Full_View
(T
))
3731 Typ
:= Full_View
(T
);
3736 -- If the allocated object will be constrained by the
3737 -- default values for discriminants, then build a subtype
3738 -- with those defaults, and change the allocated subtype
3739 -- to that. Note that this happens in fewer cases in Ada
3742 if not Is_Constrained
(Typ
)
3743 and then Present
(Discriminant_Default_Value
3744 (First_Discriminant
(Typ
)))
3745 and then (Ada_Version
< Ada_05
3747 not Has_Constrained_Partial_View
(Typ
))
3749 Typ
:= Build_Default_Subtype
(Typ
, N
);
3750 Set_Expression
(N
, New_Reference_To
(Typ
, Loc
));
3753 Discr
:= First_Elmt
(Discriminant_Constraint
(Typ
));
3754 while Present
(Discr
) loop
3755 Nod
:= Node
(Discr
);
3756 Append
(New_Copy_Tree
(Node
(Discr
)), Args
);
3758 -- AI-416: when the discriminant constraint is an
3759 -- anonymous access type make sure an accessibility
3760 -- check is inserted if necessary (3.10.2(22.q/2))
3762 if Ada_Version
>= Ada_05
3764 Ekind
(Etype
(Nod
)) = E_Anonymous_Access_Type
3766 Apply_Accessibility_Check
3767 (Nod
, Typ
, Insert_Node
=> Nod
);
3775 -- We set the allocator as analyzed so that when we analyze the
3776 -- expression actions node, we do not get an unwanted recursive
3777 -- expansion of the allocator expression.
3779 Set_Analyzed
(N
, True);
3780 Nod
:= Relocate_Node
(N
);
3782 -- Here is the transformation:
3784 -- output: Temp : constant ptr_T := new T;
3785 -- Init (Temp.all, ...);
3786 -- <CTRL> Attach_To_Final_List (Finalizable (Temp.all));
3787 -- <CTRL> Initialize (Finalizable (Temp.all));
3789 -- Here ptr_T is the pointer type for the allocator, and is the
3790 -- subtype of the allocator.
3793 Make_Object_Declaration
(Loc
,
3794 Defining_Identifier
=> Temp
,
3795 Constant_Present
=> True,
3796 Object_Definition
=> New_Reference_To
(Temp_Type
, Loc
),
3799 Set_Assignment_OK
(Temp_Decl
);
3800 Insert_Action
(N
, Temp_Decl
, Suppress
=> All_Checks
);
3802 -- If the designated type is a task type or contains tasks,
3803 -- create block to activate created tasks, and insert
3804 -- declaration for Task_Image variable ahead of call.
3806 if Has_Task
(T
) then
3808 L
: constant List_Id
:= New_List
;
3811 Build_Task_Allocate_Block
(L
, Nod
, Args
);
3813 Insert_List_Before
(First
(Declarations
(Blk
)), Decls
);
3814 Insert_Actions
(N
, L
);
3819 Make_Procedure_Call_Statement
(Loc
,
3820 Name
=> New_Reference_To
(Init
, Loc
),
3821 Parameter_Associations
=> Args
));
3824 if Needs_Finalization
(T
) then
3826 -- Postpone the generation of a finalization call for the
3827 -- current allocator if it acts as a coextension.
3829 if Is_Dynamic_Coextension
(N
) then
3830 if No
(Coextensions
(N
)) then
3831 Set_Coextensions
(N
, New_Elmt_List
);
3834 Append_Elmt
(New_Copy_Tree
(Arg1
), Coextensions
(N
));
3838 Get_Allocator_Final_List
(N
, Base_Type
(T
), PtrT
);
3840 -- Anonymous access types created for access parameters
3841 -- are attached to an explicitly constructed controller,
3842 -- which ensures that they can be finalized properly,
3843 -- even if their deallocation might not happen. The list
3844 -- associated with the controller is doubly-linked. For
3845 -- other anonymous access types, the object may end up
3846 -- on the global final list which is singly-linked.
3847 -- Work needed for access discriminants in Ada 2005 ???
3849 if Ekind
(PtrT
) = E_Anonymous_Access_Type
then
3850 Attach_Level
:= Uint_1
;
3852 Attach_Level
:= Uint_2
;
3857 Ref
=> New_Copy_Tree
(Arg1
),
3860 With_Attach
=> Make_Integer_Literal
(Loc
,
3861 Intval
=> Attach_Level
)));
3865 Rewrite
(N
, New_Reference_To
(Temp
, Loc
));
3866 Analyze_And_Resolve
(N
, PtrT
);
3871 -- Ada 2005 (AI-251): If the allocator is for a class-wide interface
3872 -- object that has been rewritten as a reference, we displace "this"
3873 -- to reference properly its secondary dispatch table.
3875 if Nkind
(N
) = N_Identifier
3876 and then Is_Interface
(Dtyp
)
3878 Displace_Allocator_Pointer
(N
);
3882 when RE_Not_Available
=>
3884 end Expand_N_Allocator
;
3886 -----------------------
3887 -- Expand_N_And_Then --
3888 -----------------------
3890 procedure Expand_N_And_Then
(N
: Node_Id
)
3891 renames Expand_Short_Circuit_Operator
;
3893 ------------------------------
3894 -- Expand_N_Case_Expression --
3895 ------------------------------
3897 procedure Expand_N_Case_Expression
(N
: Node_Id
) is
3898 Loc
: constant Source_Ptr
:= Sloc
(N
);
3899 Typ
: constant Entity_Id
:= Etype
(N
);
3911 -- case X is when A => AX, when B => BX ...
3926 -- However, this expansion is wrong for limited types, and also
3927 -- wrong for unconstrained types (since the bounds may not be the
3928 -- same in all branches). Furthermore it involves an extra copy
3929 -- for large objects. So we take care of this by using the following
3930 -- modified expansion for non-scalar types:
3933 -- type Pnn is access all typ;
3937 -- T := AX'Unrestricted_Access;
3939 -- T := BX'Unrestricted_Access;
3945 Make_Case_Statement
(Loc
,
3946 Expression
=> Expression
(N
),
3947 Alternatives
=> New_List
);
3949 Actions
:= New_List
;
3953 if Is_Scalar_Type
(Typ
) then
3957 Pnn
:= Make_Temporary
(Loc
, 'P');
3959 Make_Full_Type_Declaration
(Loc
,
3960 Defining_Identifier
=> Pnn
,
3962 Make_Access_To_Object_Definition
(Loc
,
3963 All_Present
=> True,
3964 Subtype_Indication
=>
3965 New_Reference_To
(Typ
, Loc
))));
3969 Tnn
:= Make_Temporary
(Loc
, 'T');
3971 Make_Object_Declaration
(Loc
,
3972 Defining_Identifier
=> Tnn
,
3973 Object_Definition
=> New_Occurrence_Of
(Ttyp
, Loc
)));
3975 -- Now process the alternatives
3977 Alt
:= First
(Alternatives
(N
));
3978 while Present
(Alt
) loop
3980 Aexp
: Node_Id
:= Expression
(Alt
);
3981 Aloc
: constant Source_Ptr
:= Sloc
(Aexp
);
3984 if not Is_Scalar_Type
(Typ
) then
3986 Make_Attribute_Reference
(Aloc
,
3987 Prefix
=> Relocate_Node
(Aexp
),
3988 Attribute_Name
=> Name_Unrestricted_Access
);
3992 (Alternatives
(Cstmt
),
3993 Make_Case_Statement_Alternative
(Sloc
(Alt
),
3994 Discrete_Choices
=> Discrete_Choices
(Alt
),
3995 Statements
=> New_List
(
3996 Make_Assignment_Statement
(Aloc
,
3997 Name
=> New_Occurrence_Of
(Tnn
, Loc
),
3998 Expression
=> Aexp
))));
4004 Append_To
(Actions
, Cstmt
);
4006 -- Construct and return final expression with actions
4008 if Is_Scalar_Type
(Typ
) then
4009 Fexp
:= New_Occurrence_Of
(Tnn
, Loc
);
4012 Make_Explicit_Dereference
(Loc
,
4013 Prefix
=> New_Occurrence_Of
(Tnn
, Loc
));
4017 Make_Expression_With_Actions
(Loc
,
4019 Actions
=> Actions
));
4021 Analyze_And_Resolve
(N
, Typ
);
4022 end Expand_N_Case_Expression
;
4024 -------------------------------------
4025 -- Expand_N_Conditional_Expression --
4026 -------------------------------------
4028 -- Deal with limited types and expression actions
4030 procedure Expand_N_Conditional_Expression
(N
: Node_Id
) is
4031 Loc
: constant Source_Ptr
:= Sloc
(N
);
4032 Cond
: constant Node_Id
:= First
(Expressions
(N
));
4033 Thenx
: constant Node_Id
:= Next
(Cond
);
4034 Elsex
: constant Node_Id
:= Next
(Thenx
);
4035 Typ
: constant Entity_Id
:= Etype
(N
);
4046 -- Fold at compile time if condition known. We have already folded
4047 -- static conditional expressions, but it is possible to fold any
4048 -- case in which the condition is known at compile time, even though
4049 -- the result is non-static.
4051 -- Note that we don't do the fold of such cases in Sem_Elab because
4052 -- it can cause infinite loops with the expander adding a conditional
4053 -- expression, and Sem_Elab circuitry removing it repeatedly.
4055 if Compile_Time_Known_Value
(Cond
) then
4056 if Is_True
(Expr_Value
(Cond
)) then
4058 Actions
:= Then_Actions
(N
);
4061 Actions
:= Else_Actions
(N
);
4066 if Present
(Actions
) then
4068 -- If we are not allowed to use Expression_With_Actions, just
4069 -- skip the optimization, it is not critical for correctness.
4071 if not Use_Expression_With_Actions
then
4072 goto Skip_Optimization
;
4076 Make_Expression_With_Actions
(Loc
,
4077 Expression
=> Relocate_Node
(Expr
),
4078 Actions
=> Actions
));
4079 Analyze_And_Resolve
(N
, Typ
);
4082 Rewrite
(N
, Relocate_Node
(Expr
));
4085 -- Note that the result is never static (legitimate cases of static
4086 -- conditional expressions were folded in Sem_Eval).
4088 Set_Is_Static_Expression
(N
, False);
4092 <<Skip_Optimization
>>
4094 -- If the type is limited or unconstrained, we expand as follows to
4095 -- avoid any possibility of improper copies.
4097 -- Note: it may be possible to avoid this special processing if the
4098 -- back end uses its own mechanisms for handling by-reference types ???
4100 -- type Ptr is access all Typ;
4104 -- Cnn := then-expr'Unrestricted_Access;
4107 -- Cnn := else-expr'Unrestricted_Access;
4110 -- and replace the conditional expresion by a reference to Cnn.all.
4112 -- This special case can be skipped if the back end handles limited
4113 -- types properly and ensures that no incorrect copies are made.
4115 if Is_By_Reference_Type
(Typ
)
4116 and then not Back_End_Handles_Limited_Types
4118 Cnn
:= Make_Temporary
(Loc
, 'C', N
);
4121 Make_Full_Type_Declaration
(Loc
,
4122 Defining_Identifier
=> Make_Temporary
(Loc
, 'A'),
4124 Make_Access_To_Object_Definition
(Loc
,
4125 All_Present
=> True,
4126 Subtype_Indication
=>
4127 New_Reference_To
(Typ
, Loc
)));
4129 Insert_Action
(N
, P_Decl
);
4132 Make_Object_Declaration
(Loc
,
4133 Defining_Identifier
=> Cnn
,
4134 Object_Definition
=>
4135 New_Occurrence_Of
(Defining_Identifier
(P_Decl
), Loc
));
4138 Make_Implicit_If_Statement
(N
,
4139 Condition
=> Relocate_Node
(Cond
),
4141 Then_Statements
=> New_List
(
4142 Make_Assignment_Statement
(Sloc
(Thenx
),
4143 Name
=> New_Occurrence_Of
(Cnn
, Sloc
(Thenx
)),
4145 Make_Attribute_Reference
(Loc
,
4146 Attribute_Name
=> Name_Unrestricted_Access
,
4147 Prefix
=> Relocate_Node
(Thenx
)))),
4149 Else_Statements
=> New_List
(
4150 Make_Assignment_Statement
(Sloc
(Elsex
),
4151 Name
=> New_Occurrence_Of
(Cnn
, Sloc
(Elsex
)),
4153 Make_Attribute_Reference
(Loc
,
4154 Attribute_Name
=> Name_Unrestricted_Access
,
4155 Prefix
=> Relocate_Node
(Elsex
)))));
4158 Make_Explicit_Dereference
(Loc
,
4159 Prefix
=> New_Occurrence_Of
(Cnn
, Loc
));
4161 -- For other types, we only need to expand if there are other actions
4162 -- associated with either branch.
4164 elsif Present
(Then_Actions
(N
)) or else Present
(Else_Actions
(N
)) then
4166 -- We have two approaches to handling this. If we are allowed to use
4167 -- N_Expression_With_Actions, then we can just wrap the actions into
4168 -- the appropriate expression.
4170 if Use_Expression_With_Actions
then
4171 if Present
(Then_Actions
(N
)) then
4173 Make_Expression_With_Actions
(Sloc
(Thenx
),
4174 Actions
=> Then_Actions
(N
),
4175 Expression
=> Relocate_Node
(Thenx
)));
4176 Set_Then_Actions
(N
, No_List
);
4177 Analyze_And_Resolve
(Thenx
, Typ
);
4180 if Present
(Else_Actions
(N
)) then
4182 Make_Expression_With_Actions
(Sloc
(Elsex
),
4183 Actions
=> Else_Actions
(N
),
4184 Expression
=> Relocate_Node
(Elsex
)));
4185 Set_Else_Actions
(N
, No_List
);
4186 Analyze_And_Resolve
(Elsex
, Typ
);
4191 -- if we can't use N_Expression_With_Actions nodes, then we insert
4192 -- the following sequence of actions (using Insert_Actions):
4197 -- Cnn := then-expr;
4203 -- and replace the conditional expression by a reference to Cnn
4206 Cnn
:= Make_Temporary
(Loc
, 'C', N
);
4209 Make_Object_Declaration
(Loc
,
4210 Defining_Identifier
=> Cnn
,
4211 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
));
4214 Make_Implicit_If_Statement
(N
,
4215 Condition
=> Relocate_Node
(Cond
),
4217 Then_Statements
=> New_List
(
4218 Make_Assignment_Statement
(Sloc
(Thenx
),
4219 Name
=> New_Occurrence_Of
(Cnn
, Sloc
(Thenx
)),
4220 Expression
=> Relocate_Node
(Thenx
))),
4222 Else_Statements
=> New_List
(
4223 Make_Assignment_Statement
(Sloc
(Elsex
),
4224 Name
=> New_Occurrence_Of
(Cnn
, Sloc
(Elsex
)),
4225 Expression
=> Relocate_Node
(Elsex
))));
4227 Set_Assignment_OK
(Name
(First
(Then_Statements
(New_If
))));
4228 Set_Assignment_OK
(Name
(First
(Else_Statements
(New_If
))));
4230 New_N
:= New_Occurrence_Of
(Cnn
, Loc
);
4233 -- If no actions then no expansion needed, gigi will handle it using
4234 -- the same approach as a C conditional expression.
4240 -- Fall through here for either the limited expansion, or the case of
4241 -- inserting actions for non-limited types. In both these cases, we must
4242 -- move the SLOC of the parent If statement to the newly created one and
4243 -- change it to the SLOC of the expression which, after expansion, will
4244 -- correspond to what is being evaluated.
4246 if Present
(Parent
(N
))
4247 and then Nkind
(Parent
(N
)) = N_If_Statement
4249 Set_Sloc
(New_If
, Sloc
(Parent
(N
)));
4250 Set_Sloc
(Parent
(N
), Loc
);
4253 -- Make sure Then_Actions and Else_Actions are appropriately moved
4254 -- to the new if statement.
4256 if Present
(Then_Actions
(N
)) then
4258 (First
(Then_Statements
(New_If
)), Then_Actions
(N
));
4261 if Present
(Else_Actions
(N
)) then
4263 (First
(Else_Statements
(New_If
)), Else_Actions
(N
));
4266 Insert_Action
(N
, Decl
);
4267 Insert_Action
(N
, New_If
);
4269 Analyze_And_Resolve
(N
, Typ
);
4270 end Expand_N_Conditional_Expression
;
4272 -----------------------------------
4273 -- Expand_N_Explicit_Dereference --
4274 -----------------------------------
4276 procedure Expand_N_Explicit_Dereference
(N
: Node_Id
) is
4278 -- Insert explicit dereference call for the checked storage pool case
4280 Insert_Dereference_Action
(Prefix
(N
));
4281 end Expand_N_Explicit_Dereference
;
4287 procedure Expand_N_In
(N
: Node_Id
) is
4288 Loc
: constant Source_Ptr
:= Sloc
(N
);
4289 Rtyp
: constant Entity_Id
:= Etype
(N
);
4290 Lop
: constant Node_Id
:= Left_Opnd
(N
);
4291 Rop
: constant Node_Id
:= Right_Opnd
(N
);
4292 Static
: constant Boolean := Is_OK_Static_Expression
(N
);
4294 procedure Expand_Set_Membership
;
4295 -- For each disjunct we create a simple equality or membership test.
4296 -- The whole membership is rewritten as a short-circuit disjunction.
4298 ---------------------------
4299 -- Expand_Set_Membership --
4300 ---------------------------
4302 procedure Expand_Set_Membership
is
4306 function Make_Cond
(Alt
: Node_Id
) return Node_Id
;
4307 -- If the alternative is a subtype mark, create a simple membership
4308 -- test. Otherwise create an equality test for it.
4314 function Make_Cond
(Alt
: Node_Id
) return Node_Id
is
4316 L
: constant Node_Id
:= New_Copy
(Lop
);
4317 R
: constant Node_Id
:= Relocate_Node
(Alt
);
4320 if Is_Entity_Name
(Alt
)
4321 and then Is_Type
(Entity
(Alt
))
4324 Make_In
(Sloc
(Alt
),
4328 Cond
:= Make_Op_Eq
(Sloc
(Alt
),
4336 -- Start of proessing for Expand_N_In
4339 Alt
:= Last
(Alternatives
(N
));
4340 Res
:= Make_Cond
(Alt
);
4343 while Present
(Alt
) loop
4345 Make_Or_Else
(Sloc
(Alt
),
4346 Left_Opnd
=> Make_Cond
(Alt
),
4352 Analyze_And_Resolve
(N
, Standard_Boolean
);
4353 end Expand_Set_Membership
;
4355 procedure Substitute_Valid_Check
;
4356 -- Replaces node N by Lop'Valid. This is done when we have an explicit
4357 -- test for the left operand being in range of its subtype.
4359 ----------------------------
4360 -- Substitute_Valid_Check --
4361 ----------------------------
4363 procedure Substitute_Valid_Check
is
4366 Make_Attribute_Reference
(Loc
,
4367 Prefix
=> Relocate_Node
(Lop
),
4368 Attribute_Name
=> Name_Valid
));
4370 Analyze_And_Resolve
(N
, Rtyp
);
4372 Error_Msg_N
("?explicit membership test may be optimized away", N
);
4373 Error_Msg_N
-- CODEFIX
4374 ("\?use ''Valid attribute instead", N
);
4376 end Substitute_Valid_Check
;
4378 -- Start of processing for Expand_N_In
4381 if Present
(Alternatives
(N
)) then
4382 Remove_Side_Effects
(Lop
);
4383 Expand_Set_Membership
;
4387 -- Check case of explicit test for an expression in range of its
4388 -- subtype. This is suspicious usage and we replace it with a 'Valid
4389 -- test and give a warning. For floating point types however, this is a
4390 -- standard way to check for finite numbers, and using 'Valid vould
4391 -- typically be a pessimization.
4393 if Is_Scalar_Type
(Etype
(Lop
))
4394 and then not Is_Floating_Point_Type
(Etype
(Lop
))
4395 and then Nkind
(Rop
) in N_Has_Entity
4396 and then Etype
(Lop
) = Entity
(Rop
)
4397 and then Comes_From_Source
(N
)
4398 and then VM_Target
= No_VM
4400 Substitute_Valid_Check
;
4404 -- Do validity check on operands
4406 if Validity_Checks_On
and Validity_Check_Operands
then
4407 Ensure_Valid
(Left_Opnd
(N
));
4408 Validity_Check_Range
(Right_Opnd
(N
));
4411 -- Case of explicit range
4413 if Nkind
(Rop
) = N_Range
then
4415 Lo
: constant Node_Id
:= Low_Bound
(Rop
);
4416 Hi
: constant Node_Id
:= High_Bound
(Rop
);
4418 Ltyp
: constant Entity_Id
:= Etype
(Lop
);
4420 Lo_Orig
: constant Node_Id
:= Original_Node
(Lo
);
4421 Hi_Orig
: constant Node_Id
:= Original_Node
(Hi
);
4423 Lcheck
: Compare_Result
;
4424 Ucheck
: Compare_Result
;
4426 Warn1
: constant Boolean :=
4427 Constant_Condition_Warnings
4428 and then Comes_From_Source
(N
)
4429 and then not In_Instance
;
4430 -- This must be true for any of the optimization warnings, we
4431 -- clearly want to give them only for source with the flag on. We
4432 -- also skip these warnings in an instance since it may be the
4433 -- case that different instantiations have different ranges.
4435 Warn2
: constant Boolean :=
4437 and then Nkind
(Original_Node
(Rop
)) = N_Range
4438 and then Is_Integer_Type
(Etype
(Lo
));
4439 -- For the case where only one bound warning is elided, we also
4440 -- insist on an explicit range and an integer type. The reason is
4441 -- that the use of enumeration ranges including an end point is
4442 -- common, as is the use of a subtype name, one of whose bounds is
4443 -- the same as the type of the expression.
4446 -- If test is explicit x'first .. x'last, replace by valid check
4448 if Is_Scalar_Type
(Ltyp
)
4449 and then Nkind
(Lo_Orig
) = N_Attribute_Reference
4450 and then Attribute_Name
(Lo_Orig
) = Name_First
4451 and then Nkind
(Prefix
(Lo_Orig
)) in N_Has_Entity
4452 and then Entity
(Prefix
(Lo_Orig
)) = Ltyp
4453 and then Nkind
(Hi_Orig
) = N_Attribute_Reference
4454 and then Attribute_Name
(Hi_Orig
) = Name_Last
4455 and then Nkind
(Prefix
(Hi_Orig
)) in N_Has_Entity
4456 and then Entity
(Prefix
(Hi_Orig
)) = Ltyp
4457 and then Comes_From_Source
(N
)
4458 and then VM_Target
= No_VM
4460 Substitute_Valid_Check
;
4464 -- If bounds of type are known at compile time, and the end points
4465 -- are known at compile time and identical, this is another case
4466 -- for substituting a valid test. We only do this for discrete
4467 -- types, since it won't arise in practice for float types.
4469 if Comes_From_Source
(N
)
4470 and then Is_Discrete_Type
(Ltyp
)
4471 and then Compile_Time_Known_Value
(Type_High_Bound
(Ltyp
))
4472 and then Compile_Time_Known_Value
(Type_Low_Bound
(Ltyp
))
4473 and then Compile_Time_Known_Value
(Lo
)
4474 and then Compile_Time_Known_Value
(Hi
)
4475 and then Expr_Value
(Type_High_Bound
(Ltyp
)) = Expr_Value
(Hi
)
4476 and then Expr_Value
(Type_Low_Bound
(Ltyp
)) = Expr_Value
(Lo
)
4478 -- Kill warnings in instances, since they may be cases where we
4479 -- have a test in the generic that makes sense with some types
4480 -- and not with other types.
4482 and then not In_Instance
4484 Substitute_Valid_Check
;
4488 -- If we have an explicit range, do a bit of optimization based on
4489 -- range analysis (we may be able to kill one or both checks).
4491 Lcheck
:= Compile_Time_Compare
(Lop
, Lo
, Assume_Valid
=> False);
4492 Ucheck
:= Compile_Time_Compare
(Lop
, Hi
, Assume_Valid
=> False);
4494 -- If either check is known to fail, replace result by False since
4495 -- the other check does not matter. Preserve the static flag for
4496 -- legality checks, because we are constant-folding beyond RM 4.9.
4498 if Lcheck
= LT
or else Ucheck
= GT
then
4500 Error_Msg_N
("?range test optimized away", N
);
4501 Error_Msg_N
("\?value is known to be out of range", N
);
4504 Rewrite
(N
, New_Reference_To
(Standard_False
, Loc
));
4505 Analyze_And_Resolve
(N
, Rtyp
);
4506 Set_Is_Static_Expression
(N
, Static
);
4510 -- If both checks are known to succeed, replace result by True,
4511 -- since we know we are in range.
4513 elsif Lcheck
in Compare_GE
and then Ucheck
in Compare_LE
then
4515 Error_Msg_N
("?range test optimized away", N
);
4516 Error_Msg_N
("\?value is known to be in range", N
);
4519 Rewrite
(N
, New_Reference_To
(Standard_True
, Loc
));
4520 Analyze_And_Resolve
(N
, Rtyp
);
4521 Set_Is_Static_Expression
(N
, Static
);
4525 -- If lower bound check succeeds and upper bound check is not
4526 -- known to succeed or fail, then replace the range check with
4527 -- a comparison against the upper bound.
4529 elsif Lcheck
in Compare_GE
then
4530 if Warn2
and then not In_Instance
then
4531 Error_Msg_N
("?lower bound test optimized away", Lo
);
4532 Error_Msg_N
("\?value is known to be in range", Lo
);
4538 Right_Opnd
=> High_Bound
(Rop
)));
4539 Analyze_And_Resolve
(N
, Rtyp
);
4543 -- If upper bound check succeeds and lower bound check is not
4544 -- known to succeed or fail, then replace the range check with
4545 -- a comparison against the lower bound.
4547 elsif Ucheck
in Compare_LE
then
4548 if Warn2
and then not In_Instance
then
4549 Error_Msg_N
("?upper bound test optimized away", Hi
);
4550 Error_Msg_N
("\?value is known to be in range", Hi
);
4556 Right_Opnd
=> Low_Bound
(Rop
)));
4557 Analyze_And_Resolve
(N
, Rtyp
);
4562 -- We couldn't optimize away the range check, but there is one
4563 -- more issue. If we are checking constant conditionals, then we
4564 -- see if we can determine the outcome assuming everything is
4565 -- valid, and if so give an appropriate warning.
4567 if Warn1
and then not Assume_No_Invalid_Values
then
4568 Lcheck
:= Compile_Time_Compare
(Lop
, Lo
, Assume_Valid
=> True);
4569 Ucheck
:= Compile_Time_Compare
(Lop
, Hi
, Assume_Valid
=> True);
4571 -- Result is out of range for valid value
4573 if Lcheck
= LT
or else Ucheck
= GT
then
4575 ("?value can only be in range if it is invalid", N
);
4577 -- Result is in range for valid value
4579 elsif Lcheck
in Compare_GE
and then Ucheck
in Compare_LE
then
4581 ("?value can only be out of range if it is invalid", N
);
4583 -- Lower bound check succeeds if value is valid
4585 elsif Warn2
and then Lcheck
in Compare_GE
then
4587 ("?lower bound check only fails if it is invalid", Lo
);
4589 -- Upper bound check succeeds if value is valid
4591 elsif Warn2
and then Ucheck
in Compare_LE
then
4593 ("?upper bound check only fails for invalid values", Hi
);
4598 -- For all other cases of an explicit range, nothing to be done
4602 -- Here right operand is a subtype mark
4606 Typ
: Entity_Id
:= Etype
(Rop
);
4607 Is_Acc
: constant Boolean := Is_Access_Type
(Typ
);
4608 Cond
: Node_Id
:= Empty
;
4610 Obj
: Node_Id
:= Lop
;
4611 SCIL_Node
: Node_Id
;
4614 Remove_Side_Effects
(Obj
);
4616 -- For tagged type, do tagged membership operation
4618 if Is_Tagged_Type
(Typ
) then
4620 -- No expansion will be performed when VM_Target, as the VM
4621 -- back-ends will handle the membership tests directly (tags
4622 -- are not explicitly represented in Java objects, so the
4623 -- normal tagged membership expansion is not what we want).
4625 if Tagged_Type_Expansion
then
4626 Tagged_Membership
(N
, SCIL_Node
, New_N
);
4628 Analyze_And_Resolve
(N
, Rtyp
);
4630 -- Update decoration of relocated node referenced by the
4633 if Generate_SCIL
and then Present
(SCIL_Node
) then
4634 Set_SCIL_Node
(N
, SCIL_Node
);
4640 -- If type is scalar type, rewrite as x in t'first .. t'last.
4641 -- This reason we do this is that the bounds may have the wrong
4642 -- type if they come from the original type definition. Also this
4643 -- way we get all the processing above for an explicit range.
4645 elsif Is_Scalar_Type
(Typ
) then
4649 Make_Attribute_Reference
(Loc
,
4650 Attribute_Name
=> Name_First
,
4651 Prefix
=> New_Reference_To
(Typ
, Loc
)),
4654 Make_Attribute_Reference
(Loc
,
4655 Attribute_Name
=> Name_Last
,
4656 Prefix
=> New_Reference_To
(Typ
, Loc
))));
4657 Analyze_And_Resolve
(N
, Rtyp
);
4660 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
4661 -- a membership test if the subtype mark denotes a constrained
4662 -- Unchecked_Union subtype and the expression lacks inferable
4665 elsif Is_Unchecked_Union
(Base_Type
(Typ
))
4666 and then Is_Constrained
(Typ
)
4667 and then not Has_Inferable_Discriminants
(Lop
)
4670 Make_Raise_Program_Error
(Loc
,
4671 Reason
=> PE_Unchecked_Union_Restriction
));
4673 -- Prevent Gigi from generating incorrect code by rewriting the
4676 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
4680 -- Here we have a non-scalar type
4683 Typ
:= Designated_Type
(Typ
);
4686 if not Is_Constrained
(Typ
) then
4687 Rewrite
(N
, New_Reference_To
(Standard_True
, Loc
));
4688 Analyze_And_Resolve
(N
, Rtyp
);
4690 -- For the constrained array case, we have to check the subscripts
4691 -- for an exact match if the lengths are non-zero (the lengths
4692 -- must match in any case).
4694 elsif Is_Array_Type
(Typ
) then
4695 Check_Subscripts
: declare
4696 function Build_Attribute_Reference
4699 Dim
: Nat
) return Node_Id
;
4700 -- Build attribute reference E'Nam (Dim)
4702 -------------------------------
4703 -- Build_Attribute_Reference --
4704 -------------------------------
4706 function Build_Attribute_Reference
4709 Dim
: Nat
) return Node_Id
4713 Make_Attribute_Reference
(Loc
,
4715 Attribute_Name
=> Nam
,
4716 Expressions
=> New_List
(
4717 Make_Integer_Literal
(Loc
, Dim
)));
4718 end Build_Attribute_Reference
;
4720 -- Start of processing for Check_Subscripts
4723 for J
in 1 .. Number_Dimensions
(Typ
) loop
4724 Evolve_And_Then
(Cond
,
4727 Build_Attribute_Reference
4728 (Duplicate_Subexpr_No_Checks
(Obj
),
4731 Build_Attribute_Reference
4732 (New_Occurrence_Of
(Typ
, Loc
), Name_First
, J
)));
4734 Evolve_And_Then
(Cond
,
4737 Build_Attribute_Reference
4738 (Duplicate_Subexpr_No_Checks
(Obj
),
4741 Build_Attribute_Reference
4742 (New_Occurrence_Of
(Typ
, Loc
), Name_Last
, J
)));
4751 Right_Opnd
=> Make_Null
(Loc
)),
4752 Right_Opnd
=> Cond
);
4756 Analyze_And_Resolve
(N
, Rtyp
);
4757 end Check_Subscripts
;
4759 -- These are the cases where constraint checks may be required,
4760 -- e.g. records with possible discriminants
4763 -- Expand the test into a series of discriminant comparisons.
4764 -- The expression that is built is the negation of the one that
4765 -- is used for checking discriminant constraints.
4767 Obj
:= Relocate_Node
(Left_Opnd
(N
));
4769 if Has_Discriminants
(Typ
) then
4770 Cond
:= Make_Op_Not
(Loc
,
4771 Right_Opnd
=> Build_Discriminant_Checks
(Obj
, Typ
));
4774 Cond
:= Make_Or_Else
(Loc
,
4778 Right_Opnd
=> Make_Null
(Loc
)),
4779 Right_Opnd
=> Cond
);
4783 Cond
:= New_Occurrence_Of
(Standard_True
, Loc
);
4787 Analyze_And_Resolve
(N
, Rtyp
);
4793 --------------------------------
4794 -- Expand_N_Indexed_Component --
4795 --------------------------------
4797 procedure Expand_N_Indexed_Component
(N
: Node_Id
) is
4798 Loc
: constant Source_Ptr
:= Sloc
(N
);
4799 Typ
: constant Entity_Id
:= Etype
(N
);
4800 P
: constant Node_Id
:= Prefix
(N
);
4801 T
: constant Entity_Id
:= Etype
(P
);
4804 -- A special optimization, if we have an indexed component that is
4805 -- selecting from a slice, then we can eliminate the slice, since, for
4806 -- example, x (i .. j)(k) is identical to x(k). The only difference is
4807 -- the range check required by the slice. The range check for the slice
4808 -- itself has already been generated. The range check for the
4809 -- subscripting operation is ensured by converting the subject to
4810 -- the subtype of the slice.
4812 -- This optimization not only generates better code, avoiding slice
4813 -- messing especially in the packed case, but more importantly bypasses
4814 -- some problems in handling this peculiar case, for example, the issue
4815 -- of dealing specially with object renamings.
4817 if Nkind
(P
) = N_Slice
then
4819 Make_Indexed_Component
(Loc
,
4820 Prefix
=> Prefix
(P
),
4821 Expressions
=> New_List
(
4823 (Etype
(First_Index
(Etype
(P
))),
4824 First
(Expressions
(N
))))));
4825 Analyze_And_Resolve
(N
, Typ
);
4829 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
4830 -- function, then additional actuals must be passed.
4832 if Ada_Version
>= Ada_05
4833 and then Is_Build_In_Place_Function_Call
(P
)
4835 Make_Build_In_Place_Call_In_Anonymous_Context
(P
);
4838 -- If the prefix is an access type, then we unconditionally rewrite if
4839 -- as an explicit dereference. This simplifies processing for several
4840 -- cases, including packed array cases and certain cases in which checks
4841 -- must be generated. We used to try to do this only when it was
4842 -- necessary, but it cleans up the code to do it all the time.
4844 if Is_Access_Type
(T
) then
4845 Insert_Explicit_Dereference
(P
);
4846 Analyze_And_Resolve
(P
, Designated_Type
(T
));
4849 -- Generate index and validity checks
4851 Generate_Index_Checks
(N
);
4853 if Validity_Checks_On
and then Validity_Check_Subscripts
then
4854 Apply_Subscript_Validity_Checks
(N
);
4857 -- All done for the non-packed case
4859 if not Is_Packed
(Etype
(Prefix
(N
))) then
4863 -- For packed arrays that are not bit-packed (i.e. the case of an array
4864 -- with one or more index types with a non-contiguous enumeration type),
4865 -- we can always use the normal packed element get circuit.
4867 if not Is_Bit_Packed_Array
(Etype
(Prefix
(N
))) then
4868 Expand_Packed_Element_Reference
(N
);
4872 -- For a reference to a component of a bit packed array, we have to
4873 -- convert it to a reference to the corresponding Packed_Array_Type.
4874 -- We only want to do this for simple references, and not for:
4876 -- Left side of assignment, or prefix of left side of assignment, or
4877 -- prefix of the prefix, to handle packed arrays of packed arrays,
4878 -- This case is handled in Exp_Ch5.Expand_N_Assignment_Statement
4880 -- Renaming objects in renaming associations
4881 -- This case is handled when a use of the renamed variable occurs
4883 -- Actual parameters for a procedure call
4884 -- This case is handled in Exp_Ch6.Expand_Actuals
4886 -- The second expression in a 'Read attribute reference
4888 -- The prefix of an address or bit or size attribute reference
4890 -- The following circuit detects these exceptions
4893 Child
: Node_Id
:= N
;
4894 Parnt
: Node_Id
:= Parent
(N
);
4898 if Nkind
(Parnt
) = N_Unchecked_Expression
then
4901 elsif Nkind_In
(Parnt
, N_Object_Renaming_Declaration
,
4902 N_Procedure_Call_Statement
)
4903 or else (Nkind
(Parnt
) = N_Parameter_Association
4905 Nkind
(Parent
(Parnt
)) = N_Procedure_Call_Statement
)
4909 elsif Nkind
(Parnt
) = N_Attribute_Reference
4910 and then (Attribute_Name
(Parnt
) = Name_Address
4912 Attribute_Name
(Parnt
) = Name_Bit
4914 Attribute_Name
(Parnt
) = Name_Size
)
4915 and then Prefix
(Parnt
) = Child
4919 elsif Nkind
(Parnt
) = N_Assignment_Statement
4920 and then Name
(Parnt
) = Child
4924 -- If the expression is an index of an indexed component, it must
4925 -- be expanded regardless of context.
4927 elsif Nkind
(Parnt
) = N_Indexed_Component
4928 and then Child
/= Prefix
(Parnt
)
4930 Expand_Packed_Element_Reference
(N
);
4933 elsif Nkind
(Parent
(Parnt
)) = N_Assignment_Statement
4934 and then Name
(Parent
(Parnt
)) = Parnt
4938 elsif Nkind
(Parnt
) = N_Attribute_Reference
4939 and then Attribute_Name
(Parnt
) = Name_Read
4940 and then Next
(First
(Expressions
(Parnt
))) = Child
4944 elsif Nkind_In
(Parnt
, N_Indexed_Component
, N_Selected_Component
)
4945 and then Prefix
(Parnt
) = Child
4950 Expand_Packed_Element_Reference
(N
);
4954 -- Keep looking up tree for unchecked expression, or if we are the
4955 -- prefix of a possible assignment left side.
4958 Parnt
:= Parent
(Child
);
4961 end Expand_N_Indexed_Component
;
4963 ---------------------
4964 -- Expand_N_Not_In --
4965 ---------------------
4967 -- Replace a not in b by not (a in b) so that the expansions for (a in b)
4968 -- can be done. This avoids needing to duplicate this expansion code.
4970 procedure Expand_N_Not_In
(N
: Node_Id
) is
4971 Loc
: constant Source_Ptr
:= Sloc
(N
);
4972 Typ
: constant Entity_Id
:= Etype
(N
);
4973 Cfs
: constant Boolean := Comes_From_Source
(N
);
4980 Left_Opnd
=> Left_Opnd
(N
),
4981 Right_Opnd
=> Right_Opnd
(N
))));
4983 -- If this is a set membership, preserve list of alternatives
4985 Set_Alternatives
(Right_Opnd
(N
), Alternatives
(Original_Node
(N
)));
4987 -- We want this to appear as coming from source if original does (see
4988 -- transformations in Expand_N_In).
4990 Set_Comes_From_Source
(N
, Cfs
);
4991 Set_Comes_From_Source
(Right_Opnd
(N
), Cfs
);
4993 -- Now analyze transformed node
4995 Analyze_And_Resolve
(N
, Typ
);
4996 end Expand_N_Not_In
;
5002 -- The only replacement required is for the case of a null of type that is
5003 -- an access to protected subprogram. We represent such access values as a
5004 -- record, and so we must replace the occurrence of null by the equivalent
5005 -- record (with a null address and a null pointer in it), so that the
5006 -- backend creates the proper value.
5008 procedure Expand_N_Null
(N
: Node_Id
) is
5009 Loc
: constant Source_Ptr
:= Sloc
(N
);
5010 Typ
: constant Entity_Id
:= Etype
(N
);
5014 if Is_Access_Protected_Subprogram_Type
(Typ
) then
5016 Make_Aggregate
(Loc
,
5017 Expressions
=> New_List
(
5018 New_Occurrence_Of
(RTE
(RE_Null_Address
), Loc
),
5022 Analyze_And_Resolve
(N
, Equivalent_Type
(Typ
));
5024 -- For subsequent semantic analysis, the node must retain its type.
5025 -- Gigi in any case replaces this type by the corresponding record
5026 -- type before processing the node.
5032 when RE_Not_Available
=>
5036 ---------------------
5037 -- Expand_N_Op_Abs --
5038 ---------------------
5040 procedure Expand_N_Op_Abs
(N
: Node_Id
) is
5041 Loc
: constant Source_Ptr
:= Sloc
(N
);
5042 Expr
: constant Node_Id
:= Right_Opnd
(N
);
5045 Unary_Op_Validity_Checks
(N
);
5047 -- Deal with software overflow checking
5049 if not Backend_Overflow_Checks_On_Target
5050 and then Is_Signed_Integer_Type
(Etype
(N
))
5051 and then Do_Overflow_Check
(N
)
5053 -- The only case to worry about is when the argument is equal to the
5054 -- largest negative number, so what we do is to insert the check:
5056 -- [constraint_error when Expr = typ'Base'First]
5058 -- with the usual Duplicate_Subexpr use coding for expr
5061 Make_Raise_Constraint_Error
(Loc
,
5064 Left_Opnd
=> Duplicate_Subexpr
(Expr
),
5066 Make_Attribute_Reference
(Loc
,
5068 New_Occurrence_Of
(Base_Type
(Etype
(Expr
)), Loc
),
5069 Attribute_Name
=> Name_First
)),
5070 Reason
=> CE_Overflow_Check_Failed
));
5073 -- Vax floating-point types case
5075 if Vax_Float
(Etype
(N
)) then
5076 Expand_Vax_Arith
(N
);
5078 end Expand_N_Op_Abs
;
5080 ---------------------
5081 -- Expand_N_Op_Add --
5082 ---------------------
5084 procedure Expand_N_Op_Add
(N
: Node_Id
) is
5085 Typ
: constant Entity_Id
:= Etype
(N
);
5088 Binary_Op_Validity_Checks
(N
);
5090 -- N + 0 = 0 + N = N for integer types
5092 if Is_Integer_Type
(Typ
) then
5093 if Compile_Time_Known_Value
(Right_Opnd
(N
))
5094 and then Expr_Value
(Right_Opnd
(N
)) = Uint_0
5096 Rewrite
(N
, Left_Opnd
(N
));
5099 elsif Compile_Time_Known_Value
(Left_Opnd
(N
))
5100 and then Expr_Value
(Left_Opnd
(N
)) = Uint_0
5102 Rewrite
(N
, Right_Opnd
(N
));
5107 -- Arithmetic overflow checks for signed integer/fixed point types
5109 if Is_Signed_Integer_Type
(Typ
)
5110 or else Is_Fixed_Point_Type
(Typ
)
5112 Apply_Arithmetic_Overflow_Check
(N
);
5115 -- Vax floating-point types case
5117 elsif Vax_Float
(Typ
) then
5118 Expand_Vax_Arith
(N
);
5120 end Expand_N_Op_Add
;
5122 ---------------------
5123 -- Expand_N_Op_And --
5124 ---------------------
5126 procedure Expand_N_Op_And
(N
: Node_Id
) is
5127 Typ
: constant Entity_Id
:= Etype
(N
);
5130 Binary_Op_Validity_Checks
(N
);
5132 if Is_Array_Type
(Etype
(N
)) then
5133 Expand_Boolean_Operator
(N
);
5135 elsif Is_Boolean_Type
(Etype
(N
)) then
5137 -- Replace AND by AND THEN if Short_Circuit_And_Or active and the
5138 -- type is standard Boolean (do not mess with AND that uses a non-
5139 -- standard Boolean type, because something strange is going on).
5141 if Short_Circuit_And_Or
and then Typ
= Standard_Boolean
then
5143 Make_And_Then
(Sloc
(N
),
5144 Left_Opnd
=> Relocate_Node
(Left_Opnd
(N
)),
5145 Right_Opnd
=> Relocate_Node
(Right_Opnd
(N
))));
5146 Analyze_And_Resolve
(N
, Typ
);
5148 -- Otherwise, adjust conditions
5151 Adjust_Condition
(Left_Opnd
(N
));
5152 Adjust_Condition
(Right_Opnd
(N
));
5153 Set_Etype
(N
, Standard_Boolean
);
5154 Adjust_Result_Type
(N
, Typ
);
5157 end Expand_N_Op_And
;
5159 ------------------------
5160 -- Expand_N_Op_Concat --
5161 ------------------------
5163 procedure Expand_N_Op_Concat
(N
: Node_Id
) is
5165 -- List of operands to be concatenated
5168 -- Node which is to be replaced by the result of concatenating the nodes
5169 -- in the list Opnds.
5172 -- Ensure validity of both operands
5174 Binary_Op_Validity_Checks
(N
);
5176 -- If we are the left operand of a concatenation higher up the tree,
5177 -- then do nothing for now, since we want to deal with a series of
5178 -- concatenations as a unit.
5180 if Nkind
(Parent
(N
)) = N_Op_Concat
5181 and then N
= Left_Opnd
(Parent
(N
))
5186 -- We get here with a concatenation whose left operand may be a
5187 -- concatenation itself with a consistent type. We need to process
5188 -- these concatenation operands from left to right, which means
5189 -- from the deepest node in the tree to the highest node.
5192 while Nkind
(Left_Opnd
(Cnode
)) = N_Op_Concat
loop
5193 Cnode
:= Left_Opnd
(Cnode
);
5196 -- Now Cnode is the deepest concatenation, and its parents are the
5197 -- concatenation nodes above, so now we process bottom up, doing the
5198 -- operations. We gather a string that is as long as possible up to five
5201 -- The outer loop runs more than once if more than one concatenation
5202 -- type is involved.
5205 Opnds
:= New_List
(Left_Opnd
(Cnode
), Right_Opnd
(Cnode
));
5206 Set_Parent
(Opnds
, N
);
5208 -- The inner loop gathers concatenation operands
5210 Inner
: while Cnode
/= N
5211 and then Base_Type
(Etype
(Cnode
)) =
5212 Base_Type
(Etype
(Parent
(Cnode
)))
5214 Cnode
:= Parent
(Cnode
);
5215 Append
(Right_Opnd
(Cnode
), Opnds
);
5218 Expand_Concatenate
(Cnode
, Opnds
);
5220 exit Outer
when Cnode
= N
;
5221 Cnode
:= Parent
(Cnode
);
5223 end Expand_N_Op_Concat
;
5225 ------------------------
5226 -- Expand_N_Op_Divide --
5227 ------------------------
5229 procedure Expand_N_Op_Divide
(N
: Node_Id
) is
5230 Loc
: constant Source_Ptr
:= Sloc
(N
);
5231 Lopnd
: constant Node_Id
:= Left_Opnd
(N
);
5232 Ropnd
: constant Node_Id
:= Right_Opnd
(N
);
5233 Ltyp
: constant Entity_Id
:= Etype
(Lopnd
);
5234 Rtyp
: constant Entity_Id
:= Etype
(Ropnd
);
5235 Typ
: Entity_Id
:= Etype
(N
);
5236 Rknow
: constant Boolean := Is_Integer_Type
(Typ
)
5238 Compile_Time_Known_Value
(Ropnd
);
5242 Binary_Op_Validity_Checks
(N
);
5245 Rval
:= Expr_Value
(Ropnd
);
5248 -- N / 1 = N for integer types
5250 if Rknow
and then Rval
= Uint_1
then
5255 -- Convert x / 2 ** y to Shift_Right (x, y). Note that the fact that
5256 -- Is_Power_Of_2_For_Shift is set means that we know that our left
5257 -- operand is an unsigned integer, as required for this to work.
5259 if Nkind
(Ropnd
) = N_Op_Expon
5260 and then Is_Power_Of_2_For_Shift
(Ropnd
)
5262 -- We cannot do this transformation in configurable run time mode if we
5263 -- have 64-bit integers and long shifts are not available.
5267 or else Support_Long_Shifts_On_Target
)
5270 Make_Op_Shift_Right
(Loc
,
5273 Convert_To
(Standard_Natural
, Right_Opnd
(Ropnd
))));
5274 Analyze_And_Resolve
(N
, Typ
);
5278 -- Do required fixup of universal fixed operation
5280 if Typ
= Universal_Fixed
then
5281 Fixup_Universal_Fixed_Operation
(N
);
5285 -- Divisions with fixed-point results
5287 if Is_Fixed_Point_Type
(Typ
) then
5289 -- No special processing if Treat_Fixed_As_Integer is set, since
5290 -- from a semantic point of view such operations are simply integer
5291 -- operations and will be treated that way.
5293 if not Treat_Fixed_As_Integer
(N
) then
5294 if Is_Integer_Type
(Rtyp
) then
5295 Expand_Divide_Fixed_By_Integer_Giving_Fixed
(N
);
5297 Expand_Divide_Fixed_By_Fixed_Giving_Fixed
(N
);
5301 -- Other cases of division of fixed-point operands. Again we exclude the
5302 -- case where Treat_Fixed_As_Integer is set.
5304 elsif (Is_Fixed_Point_Type
(Ltyp
) or else
5305 Is_Fixed_Point_Type
(Rtyp
))
5306 and then not Treat_Fixed_As_Integer
(N
)
5308 if Is_Integer_Type
(Typ
) then
5309 Expand_Divide_Fixed_By_Fixed_Giving_Integer
(N
);
5311 pragma Assert
(Is_Floating_Point_Type
(Typ
));
5312 Expand_Divide_Fixed_By_Fixed_Giving_Float
(N
);
5315 -- Mixed-mode operations can appear in a non-static universal context,
5316 -- in which case the integer argument must be converted explicitly.
5318 elsif Typ
= Universal_Real
5319 and then Is_Integer_Type
(Rtyp
)
5322 Convert_To
(Universal_Real
, Relocate_Node
(Ropnd
)));
5324 Analyze_And_Resolve
(Ropnd
, Universal_Real
);
5326 elsif Typ
= Universal_Real
5327 and then Is_Integer_Type
(Ltyp
)
5330 Convert_To
(Universal_Real
, Relocate_Node
(Lopnd
)));
5332 Analyze_And_Resolve
(Lopnd
, Universal_Real
);
5334 -- Non-fixed point cases, do integer zero divide and overflow checks
5336 elsif Is_Integer_Type
(Typ
) then
5337 Apply_Divide_Check
(N
);
5339 -- Check for 64-bit division available, or long shifts if the divisor
5340 -- is a small power of 2 (since such divides will be converted into
5343 if Esize
(Ltyp
) > 32
5344 and then not Support_64_Bit_Divides_On_Target
5347 or else not Support_Long_Shifts_On_Target
5348 or else (Rval
/= Uint_2
and then
5349 Rval
/= Uint_4
and then
5350 Rval
/= Uint_8
and then
5351 Rval
/= Uint_16
and then
5352 Rval
/= Uint_32
and then
5355 Error_Msg_CRT
("64-bit division", N
);
5358 -- Deal with Vax_Float
5360 elsif Vax_Float
(Typ
) then
5361 Expand_Vax_Arith
(N
);
5364 end Expand_N_Op_Divide
;
5366 --------------------
5367 -- Expand_N_Op_Eq --
5368 --------------------
5370 procedure Expand_N_Op_Eq
(N
: Node_Id
) is
5371 Loc
: constant Source_Ptr
:= Sloc
(N
);
5372 Typ
: constant Entity_Id
:= Etype
(N
);
5373 Lhs
: constant Node_Id
:= Left_Opnd
(N
);
5374 Rhs
: constant Node_Id
:= Right_Opnd
(N
);
5375 Bodies
: constant List_Id
:= New_List
;
5376 A_Typ
: constant Entity_Id
:= Etype
(Lhs
);
5378 Typl
: Entity_Id
:= A_Typ
;
5379 Op_Name
: Entity_Id
;
5382 procedure Build_Equality_Call
(Eq
: Entity_Id
);
5383 -- If a constructed equality exists for the type or for its parent,
5384 -- build and analyze call, adding conversions if the operation is
5387 function Has_Unconstrained_UU_Component
(Typ
: Node_Id
) return Boolean;
5388 -- Determines whether a type has a subcomponent of an unconstrained
5389 -- Unchecked_Union subtype. Typ is a record type.
5391 -------------------------
5392 -- Build_Equality_Call --
5393 -------------------------
5395 procedure Build_Equality_Call
(Eq
: Entity_Id
) is
5396 Op_Type
: constant Entity_Id
:= Etype
(First_Formal
(Eq
));
5397 L_Exp
: Node_Id
:= Relocate_Node
(Lhs
);
5398 R_Exp
: Node_Id
:= Relocate_Node
(Rhs
);
5401 if Base_Type
(Op_Type
) /= Base_Type
(A_Typ
)
5402 and then not Is_Class_Wide_Type
(A_Typ
)
5404 L_Exp
:= OK_Convert_To
(Op_Type
, L_Exp
);
5405 R_Exp
:= OK_Convert_To
(Op_Type
, R_Exp
);
5408 -- If we have an Unchecked_Union, we need to add the inferred
5409 -- discriminant values as actuals in the function call. At this
5410 -- point, the expansion has determined that both operands have
5411 -- inferable discriminants.
5413 if Is_Unchecked_Union
(Op_Type
) then
5415 Lhs_Type
: constant Node_Id
:= Etype
(L_Exp
);
5416 Rhs_Type
: constant Node_Id
:= Etype
(R_Exp
);
5417 Lhs_Discr_Val
: Node_Id
;
5418 Rhs_Discr_Val
: Node_Id
;
5421 -- Per-object constrained selected components require special
5422 -- attention. If the enclosing scope of the component is an
5423 -- Unchecked_Union, we cannot reference its discriminants
5424 -- directly. This is why we use the two extra parameters of
5425 -- the equality function of the enclosing Unchecked_Union.
5427 -- type UU_Type (Discr : Integer := 0) is
5430 -- pragma Unchecked_Union (UU_Type);
5432 -- 1. Unchecked_Union enclosing record:
5434 -- type Enclosing_UU_Type (Discr : Integer := 0) is record
5436 -- Comp : UU_Type (Discr);
5438 -- end Enclosing_UU_Type;
5439 -- pragma Unchecked_Union (Enclosing_UU_Type);
5441 -- Obj1 : Enclosing_UU_Type;
5442 -- Obj2 : Enclosing_UU_Type (1);
5444 -- [. . .] Obj1 = Obj2 [. . .]
5448 -- if not (uu_typeEQ (obj1.comp, obj2.comp, a, b)) then
5450 -- A and B are the formal parameters of the equality function
5451 -- of Enclosing_UU_Type. The function always has two extra
5452 -- formals to capture the inferred discriminant values.
5454 -- 2. Non-Unchecked_Union enclosing record:
5457 -- Enclosing_Non_UU_Type (Discr : Integer := 0)
5460 -- Comp : UU_Type (Discr);
5462 -- end Enclosing_Non_UU_Type;
5464 -- Obj1 : Enclosing_Non_UU_Type;
5465 -- Obj2 : Enclosing_Non_UU_Type (1);
5467 -- ... Obj1 = Obj2 ...
5471 -- if not (uu_typeEQ (obj1.comp, obj2.comp,
5472 -- obj1.discr, obj2.discr)) then
5474 -- In this case we can directly reference the discriminants of
5475 -- the enclosing record.
5479 if Nkind
(Lhs
) = N_Selected_Component
5480 and then Has_Per_Object_Constraint
5481 (Entity
(Selector_Name
(Lhs
)))
5483 -- Enclosing record is an Unchecked_Union, use formal A
5485 if Is_Unchecked_Union
(Scope
5486 (Entity
(Selector_Name
(Lhs
))))
5489 Make_Identifier
(Loc
,
5492 -- Enclosing record is of a non-Unchecked_Union type, it is
5493 -- possible to reference the discriminant.
5497 Make_Selected_Component
(Loc
,
5498 Prefix
=> Prefix
(Lhs
),
5501 (Get_Discriminant_Value
5502 (First_Discriminant
(Lhs_Type
),
5504 Stored_Constraint
(Lhs_Type
))));
5507 -- Comment needed here ???
5510 -- Infer the discriminant value
5514 (Get_Discriminant_Value
5515 (First_Discriminant
(Lhs_Type
),
5517 Stored_Constraint
(Lhs_Type
)));
5522 if Nkind
(Rhs
) = N_Selected_Component
5523 and then Has_Per_Object_Constraint
5524 (Entity
(Selector_Name
(Rhs
)))
5526 if Is_Unchecked_Union
5527 (Scope
(Entity
(Selector_Name
(Rhs
))))
5530 Make_Identifier
(Loc
,
5535 Make_Selected_Component
(Loc
,
5536 Prefix
=> Prefix
(Rhs
),
5538 New_Copy
(Get_Discriminant_Value
(
5539 First_Discriminant
(Rhs_Type
),
5541 Stored_Constraint
(Rhs_Type
))));
5546 New_Copy
(Get_Discriminant_Value
(
5547 First_Discriminant
(Rhs_Type
),
5549 Stored_Constraint
(Rhs_Type
)));
5554 Make_Function_Call
(Loc
,
5555 Name
=> New_Reference_To
(Eq
, Loc
),
5556 Parameter_Associations
=> New_List
(
5563 -- Normal case, not an unchecked union
5567 Make_Function_Call
(Loc
,
5568 Name
=> New_Reference_To
(Eq
, Loc
),
5569 Parameter_Associations
=> New_List
(L_Exp
, R_Exp
)));
5572 Analyze_And_Resolve
(N
, Standard_Boolean
, Suppress
=> All_Checks
);
5573 end Build_Equality_Call
;
5575 ------------------------------------
5576 -- Has_Unconstrained_UU_Component --
5577 ------------------------------------
5579 function Has_Unconstrained_UU_Component
5580 (Typ
: Node_Id
) return Boolean
5582 Tdef
: constant Node_Id
:=
5583 Type_Definition
(Declaration_Node
(Base_Type
(Typ
)));
5587 function Component_Is_Unconstrained_UU
5588 (Comp
: Node_Id
) return Boolean;
5589 -- Determines whether the subtype of the component is an
5590 -- unconstrained Unchecked_Union.
5592 function Variant_Is_Unconstrained_UU
5593 (Variant
: Node_Id
) return Boolean;
5594 -- Determines whether a component of the variant has an unconstrained
5595 -- Unchecked_Union subtype.
5597 -----------------------------------
5598 -- Component_Is_Unconstrained_UU --
5599 -----------------------------------
5601 function Component_Is_Unconstrained_UU
5602 (Comp
: Node_Id
) return Boolean
5605 if Nkind
(Comp
) /= N_Component_Declaration
then
5610 Sindic
: constant Node_Id
:=
5611 Subtype_Indication
(Component_Definition
(Comp
));
5614 -- Unconstrained nominal type. In the case of a constraint
5615 -- present, the node kind would have been N_Subtype_Indication.
5617 if Nkind
(Sindic
) = N_Identifier
then
5618 return Is_Unchecked_Union
(Base_Type
(Etype
(Sindic
)));
5623 end Component_Is_Unconstrained_UU
;
5625 ---------------------------------
5626 -- Variant_Is_Unconstrained_UU --
5627 ---------------------------------
5629 function Variant_Is_Unconstrained_UU
5630 (Variant
: Node_Id
) return Boolean
5632 Clist
: constant Node_Id
:= Component_List
(Variant
);
5635 if Is_Empty_List
(Component_Items
(Clist
)) then
5639 -- We only need to test one component
5642 Comp
: Node_Id
:= First
(Component_Items
(Clist
));
5645 while Present
(Comp
) loop
5646 if Component_Is_Unconstrained_UU
(Comp
) then
5654 -- None of the components withing the variant were of
5655 -- unconstrained Unchecked_Union type.
5658 end Variant_Is_Unconstrained_UU
;
5660 -- Start of processing for Has_Unconstrained_UU_Component
5663 if Null_Present
(Tdef
) then
5667 Clist
:= Component_List
(Tdef
);
5668 Vpart
:= Variant_Part
(Clist
);
5670 -- Inspect available components
5672 if Present
(Component_Items
(Clist
)) then
5674 Comp
: Node_Id
:= First
(Component_Items
(Clist
));
5677 while Present
(Comp
) loop
5679 -- One component is sufficient
5681 if Component_Is_Unconstrained_UU
(Comp
) then
5690 -- Inspect available components withing variants
5692 if Present
(Vpart
) then
5694 Variant
: Node_Id
:= First
(Variants
(Vpart
));
5697 while Present
(Variant
) loop
5699 -- One component within a variant is sufficient
5701 if Variant_Is_Unconstrained_UU
(Variant
) then
5710 -- Neither the available components, nor the components inside the
5711 -- variant parts were of an unconstrained Unchecked_Union subtype.
5714 end Has_Unconstrained_UU_Component
;
5716 -- Start of processing for Expand_N_Op_Eq
5719 Binary_Op_Validity_Checks
(N
);
5721 if Ekind
(Typl
) = E_Private_Type
then
5722 Typl
:= Underlying_Type
(Typl
);
5723 elsif Ekind
(Typl
) = E_Private_Subtype
then
5724 Typl
:= Underlying_Type
(Base_Type
(Typl
));
5729 -- It may happen in error situations that the underlying type is not
5730 -- set. The error will be detected later, here we just defend the
5737 Typl
:= Base_Type
(Typl
);
5739 -- Boolean types (requiring handling of non-standard case)
5741 if Is_Boolean_Type
(Typl
) then
5742 Adjust_Condition
(Left_Opnd
(N
));
5743 Adjust_Condition
(Right_Opnd
(N
));
5744 Set_Etype
(N
, Standard_Boolean
);
5745 Adjust_Result_Type
(N
, Typ
);
5749 elsif Is_Array_Type
(Typl
) then
5751 -- If we are doing full validity checking, and it is possible for the
5752 -- array elements to be invalid then expand out array comparisons to
5753 -- make sure that we check the array elements.
5755 if Validity_Check_Operands
5756 and then not Is_Known_Valid
(Component_Type
(Typl
))
5759 Save_Force_Validity_Checks
: constant Boolean :=
5760 Force_Validity_Checks
;
5762 Force_Validity_Checks
:= True;
5764 Expand_Array_Equality
5766 Relocate_Node
(Lhs
),
5767 Relocate_Node
(Rhs
),
5770 Insert_Actions
(N
, Bodies
);
5771 Analyze_And_Resolve
(N
, Standard_Boolean
);
5772 Force_Validity_Checks
:= Save_Force_Validity_Checks
;
5775 -- Packed case where both operands are known aligned
5777 elsif Is_Bit_Packed_Array
(Typl
)
5778 and then not Is_Possibly_Unaligned_Object
(Lhs
)
5779 and then not Is_Possibly_Unaligned_Object
(Rhs
)
5781 Expand_Packed_Eq
(N
);
5783 -- Where the component type is elementary we can use a block bit
5784 -- comparison (if supported on the target) exception in the case
5785 -- of floating-point (negative zero issues require element by
5786 -- element comparison), and atomic types (where we must be sure
5787 -- to load elements independently) and possibly unaligned arrays.
5789 elsif Is_Elementary_Type
(Component_Type
(Typl
))
5790 and then not Is_Floating_Point_Type
(Component_Type
(Typl
))
5791 and then not Is_Atomic
(Component_Type
(Typl
))
5792 and then not Is_Possibly_Unaligned_Object
(Lhs
)
5793 and then not Is_Possibly_Unaligned_Object
(Rhs
)
5794 and then Support_Composite_Compare_On_Target
5798 -- For composite and floating-point cases, expand equality loop to
5799 -- make sure of using proper comparisons for tagged types, and
5800 -- correctly handling the floating-point case.
5804 Expand_Array_Equality
5806 Relocate_Node
(Lhs
),
5807 Relocate_Node
(Rhs
),
5810 Insert_Actions
(N
, Bodies
, Suppress
=> All_Checks
);
5811 Analyze_And_Resolve
(N
, Standard_Boolean
, Suppress
=> All_Checks
);
5816 elsif Is_Record_Type
(Typl
) then
5818 -- For tagged types, use the primitive "="
5820 if Is_Tagged_Type
(Typl
) then
5822 -- No need to do anything else compiling under restriction
5823 -- No_Dispatching_Calls. During the semantic analysis we
5824 -- already notified such violation.
5826 if Restriction_Active
(No_Dispatching_Calls
) then
5830 -- If this is derived from an untagged private type completed with
5831 -- a tagged type, it does not have a full view, so we use the
5832 -- primitive operations of the private type. This check should no
5833 -- longer be necessary when these types get their full views???
5835 if Is_Private_Type
(A_Typ
)
5836 and then not Is_Tagged_Type
(A_Typ
)
5837 and then Is_Derived_Type
(A_Typ
)
5838 and then No
(Full_View
(A_Typ
))
5840 -- Search for equality operation, checking that the operands
5841 -- have the same type. Note that we must find a matching entry,
5842 -- or something is very wrong!
5844 Prim
:= First_Elmt
(Collect_Primitive_Operations
(A_Typ
));
5846 while Present
(Prim
) loop
5847 exit when Chars
(Node
(Prim
)) = Name_Op_Eq
5848 and then Etype
(First_Formal
(Node
(Prim
))) =
5849 Etype
(Next_Formal
(First_Formal
(Node
(Prim
))))
5851 Base_Type
(Etype
(Node
(Prim
))) = Standard_Boolean
;
5856 pragma Assert
(Present
(Prim
));
5857 Op_Name
:= Node
(Prim
);
5859 -- Find the type's predefined equality or an overriding
5860 -- user- defined equality. The reason for not simply calling
5861 -- Find_Prim_Op here is that there may be a user-defined
5862 -- overloaded equality op that precedes the equality that we want,
5863 -- so we have to explicitly search (e.g., there could be an
5864 -- equality with two different parameter types).
5867 if Is_Class_Wide_Type
(Typl
) then
5868 Typl
:= Root_Type
(Typl
);
5871 Prim
:= First_Elmt
(Primitive_Operations
(Typl
));
5872 while Present
(Prim
) loop
5873 exit when Chars
(Node
(Prim
)) = Name_Op_Eq
5874 and then Etype
(First_Formal
(Node
(Prim
))) =
5875 Etype
(Next_Formal
(First_Formal
(Node
(Prim
))))
5877 Base_Type
(Etype
(Node
(Prim
))) = Standard_Boolean
;
5882 pragma Assert
(Present
(Prim
));
5883 Op_Name
:= Node
(Prim
);
5886 Build_Equality_Call
(Op_Name
);
5888 -- Ada 2005 (AI-216): Program_Error is raised when evaluating the
5889 -- predefined equality operator for a type which has a subcomponent
5890 -- of an Unchecked_Union type whose nominal subtype is unconstrained.
5892 elsif Has_Unconstrained_UU_Component
(Typl
) then
5894 Make_Raise_Program_Error
(Loc
,
5895 Reason
=> PE_Unchecked_Union_Restriction
));
5897 -- Prevent Gigi from generating incorrect code by rewriting the
5898 -- equality as a standard False.
5901 New_Occurrence_Of
(Standard_False
, Loc
));
5903 elsif Is_Unchecked_Union
(Typl
) then
5905 -- If we can infer the discriminants of the operands, we make a
5906 -- call to the TSS equality function.
5908 if Has_Inferable_Discriminants
(Lhs
)
5910 Has_Inferable_Discriminants
(Rhs
)
5913 (TSS
(Root_Type
(Typl
), TSS_Composite_Equality
));
5916 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
5917 -- the predefined equality operator for an Unchecked_Union type
5918 -- if either of the operands lack inferable discriminants.
5921 Make_Raise_Program_Error
(Loc
,
5922 Reason
=> PE_Unchecked_Union_Restriction
));
5924 -- Prevent Gigi from generating incorrect code by rewriting
5925 -- the equality as a standard False.
5928 New_Occurrence_Of
(Standard_False
, Loc
));
5932 -- If a type support function is present (for complex cases), use it
5934 elsif Present
(TSS
(Root_Type
(Typl
), TSS_Composite_Equality
)) then
5936 (TSS
(Root_Type
(Typl
), TSS_Composite_Equality
));
5938 -- Otherwise expand the component by component equality. Note that
5939 -- we never use block-bit comparisons for records, because of the
5940 -- problems with gaps. The backend will often be able to recombine
5941 -- the separate comparisons that we generate here.
5944 Remove_Side_Effects
(Lhs
);
5945 Remove_Side_Effects
(Rhs
);
5947 Expand_Record_Equality
(N
, Typl
, Lhs
, Rhs
, Bodies
));
5949 Insert_Actions
(N
, Bodies
, Suppress
=> All_Checks
);
5950 Analyze_And_Resolve
(N
, Standard_Boolean
, Suppress
=> All_Checks
);
5954 -- Test if result is known at compile time
5956 Rewrite_Comparison
(N
);
5958 -- If we still have comparison for Vax_Float, process it
5960 if Vax_Float
(Typl
) and then Nkind
(N
) in N_Op_Compare
then
5961 Expand_Vax_Comparison
(N
);
5966 -----------------------
5967 -- Expand_N_Op_Expon --
5968 -----------------------
5970 procedure Expand_N_Op_Expon
(N
: Node_Id
) is
5971 Loc
: constant Source_Ptr
:= Sloc
(N
);
5972 Typ
: constant Entity_Id
:= Etype
(N
);
5973 Rtyp
: constant Entity_Id
:= Root_Type
(Typ
);
5974 Base
: constant Node_Id
:= Relocate_Node
(Left_Opnd
(N
));
5975 Bastyp
: constant Node_Id
:= Etype
(Base
);
5976 Exp
: constant Node_Id
:= Relocate_Node
(Right_Opnd
(N
));
5977 Exptyp
: constant Entity_Id
:= Etype
(Exp
);
5978 Ovflo
: constant Boolean := Do_Overflow_Check
(N
);
5987 Binary_Op_Validity_Checks
(N
);
5989 -- If either operand is of a private type, then we have the use of an
5990 -- intrinsic operator, and we get rid of the privateness, by using root
5991 -- types of underlying types for the actual operation. Otherwise the
5992 -- private types will cause trouble if we expand multiplications or
5993 -- shifts etc. We also do this transformation if the result type is
5994 -- different from the base type.
5996 if Is_Private_Type
(Etype
(Base
))
5998 Is_Private_Type
(Typ
)
6000 Is_Private_Type
(Exptyp
)
6002 Rtyp
/= Root_Type
(Bastyp
)
6005 Bt
: constant Entity_Id
:= Root_Type
(Underlying_Type
(Bastyp
));
6006 Et
: constant Entity_Id
:= Root_Type
(Underlying_Type
(Exptyp
));
6010 Unchecked_Convert_To
(Typ
,
6012 Left_Opnd
=> Unchecked_Convert_To
(Bt
, Base
),
6013 Right_Opnd
=> Unchecked_Convert_To
(Et
, Exp
))));
6014 Analyze_And_Resolve
(N
, Typ
);
6019 -- Test for case of known right argument
6021 if Compile_Time_Known_Value
(Exp
) then
6022 Expv
:= Expr_Value
(Exp
);
6024 -- We only fold small non-negative exponents. You might think we
6025 -- could fold small negative exponents for the real case, but we
6026 -- can't because we are required to raise Constraint_Error for
6027 -- the case of 0.0 ** (negative) even if Machine_Overflows = False.
6028 -- See ACVC test C4A012B.
6030 if Expv
>= 0 and then Expv
<= 4 then
6032 -- X ** 0 = 1 (or 1.0)
6036 -- Call Remove_Side_Effects to ensure that any side effects
6037 -- in the ignored left operand (in particular function calls
6038 -- to user defined functions) are properly executed.
6040 Remove_Side_Effects
(Base
);
6042 if Ekind
(Typ
) in Integer_Kind
then
6043 Xnode
:= Make_Integer_Literal
(Loc
, Intval
=> 1);
6045 Xnode
:= Make_Real_Literal
(Loc
, Ureal_1
);
6057 Make_Op_Multiply
(Loc
,
6058 Left_Opnd
=> Duplicate_Subexpr
(Base
),
6059 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Base
));
6061 -- X ** 3 = X * X * X
6065 Make_Op_Multiply
(Loc
,
6067 Make_Op_Multiply
(Loc
,
6068 Left_Opnd
=> Duplicate_Subexpr
(Base
),
6069 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Base
)),
6070 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Base
));
6073 -- En : constant base'type := base * base;
6078 Temp
:= Make_Temporary
(Loc
, 'E', Base
);
6080 Insert_Actions
(N
, New_List
(
6081 Make_Object_Declaration
(Loc
,
6082 Defining_Identifier
=> Temp
,
6083 Constant_Present
=> True,
6084 Object_Definition
=> New_Reference_To
(Typ
, Loc
),
6086 Make_Op_Multiply
(Loc
,
6087 Left_Opnd
=> Duplicate_Subexpr
(Base
),
6088 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Base
)))));
6091 Make_Op_Multiply
(Loc
,
6092 Left_Opnd
=> New_Reference_To
(Temp
, Loc
),
6093 Right_Opnd
=> New_Reference_To
(Temp
, Loc
));
6097 Analyze_And_Resolve
(N
, Typ
);
6102 -- Case of (2 ** expression) appearing as an argument of an integer
6103 -- multiplication, or as the right argument of a division of a non-
6104 -- negative integer. In such cases we leave the node untouched, setting
6105 -- the flag Is_Natural_Power_Of_2_for_Shift set, then the expansion
6106 -- of the higher level node converts it into a shift.
6108 -- Another case is 2 ** N in any other context. We simply convert
6109 -- this to 1 * 2 ** N, and then the above transformation applies.
6111 -- Note: this transformation is not applicable for a modular type with
6112 -- a non-binary modulus in the multiplication case, since we get a wrong
6113 -- result if the shift causes an overflow before the modular reduction.
6115 if Nkind
(Base
) = N_Integer_Literal
6116 and then Intval
(Base
) = 2
6117 and then Is_Integer_Type
(Root_Type
(Exptyp
))
6118 and then Esize
(Root_Type
(Exptyp
)) <= Esize
(Standard_Integer
)
6119 and then Is_Unsigned_Type
(Exptyp
)
6122 -- First the multiply and divide cases
6124 if Nkind_In
(Parent
(N
), N_Op_Divide
, N_Op_Multiply
) then
6126 P
: constant Node_Id
:= Parent
(N
);
6127 L
: constant Node_Id
:= Left_Opnd
(P
);
6128 R
: constant Node_Id
:= Right_Opnd
(P
);
6131 if (Nkind
(P
) = N_Op_Multiply
6132 and then not Non_Binary_Modulus
(Typ
)
6134 ((Is_Integer_Type
(Etype
(L
)) and then R
= N
)
6136 (Is_Integer_Type
(Etype
(R
)) and then L
= N
))
6137 and then not Do_Overflow_Check
(P
))
6139 (Nkind
(P
) = N_Op_Divide
6140 and then Is_Integer_Type
(Etype
(L
))
6141 and then Is_Unsigned_Type
(Etype
(L
))
6143 and then not Do_Overflow_Check
(P
))
6145 Set_Is_Power_Of_2_For_Shift
(N
);
6150 -- Now the other cases
6152 elsif not Non_Binary_Modulus
(Typ
) then
6154 Make_Op_Multiply
(Loc
,
6155 Left_Opnd
=> Make_Integer_Literal
(Loc
, 1),
6156 Right_Opnd
=> Relocate_Node
(N
)));
6157 Analyze_And_Resolve
(N
, Typ
);
6162 -- Fall through if exponentiation must be done using a runtime routine
6164 -- First deal with modular case
6166 if Is_Modular_Integer_Type
(Rtyp
) then
6168 -- Non-binary case, we call the special exponentiation routine for
6169 -- the non-binary case, converting the argument to Long_Long_Integer
6170 -- and passing the modulus value. Then the result is converted back
6171 -- to the base type.
6173 if Non_Binary_Modulus
(Rtyp
) then
6176 Make_Function_Call
(Loc
,
6177 Name
=> New_Reference_To
(RTE
(RE_Exp_Modular
), Loc
),
6178 Parameter_Associations
=> New_List
(
6179 Convert_To
(Standard_Integer
, Base
),
6180 Make_Integer_Literal
(Loc
, Modulus
(Rtyp
)),
6183 -- Binary case, in this case, we call one of two routines, either the
6184 -- unsigned integer case, or the unsigned long long integer case,
6185 -- with a final "and" operation to do the required mod.
6188 if UI_To_Int
(Esize
(Rtyp
)) <= Standard_Integer_Size
then
6189 Ent
:= RTE
(RE_Exp_Unsigned
);
6191 Ent
:= RTE
(RE_Exp_Long_Long_Unsigned
);
6198 Make_Function_Call
(Loc
,
6199 Name
=> New_Reference_To
(Ent
, Loc
),
6200 Parameter_Associations
=> New_List
(
6201 Convert_To
(Etype
(First_Formal
(Ent
)), Base
),
6204 Make_Integer_Literal
(Loc
, Modulus
(Rtyp
) - 1))));
6208 -- Common exit point for modular type case
6210 Analyze_And_Resolve
(N
, Typ
);
6213 -- Signed integer cases, done using either Integer or Long_Long_Integer.
6214 -- It is not worth having routines for Short_[Short_]Integer, since for
6215 -- most machines it would not help, and it would generate more code that
6216 -- might need certification when a certified run time is required.
6218 -- In the integer cases, we have two routines, one for when overflow
6219 -- checks are required, and one when they are not required, since there
6220 -- is a real gain in omitting checks on many machines.
6222 elsif Rtyp
= Base_Type
(Standard_Long_Long_Integer
)
6223 or else (Rtyp
= Base_Type
(Standard_Long_Integer
)
6225 Esize
(Standard_Long_Integer
) > Esize
(Standard_Integer
))
6226 or else (Rtyp
= Universal_Integer
)
6228 Etyp
:= Standard_Long_Long_Integer
;
6231 Rent
:= RE_Exp_Long_Long_Integer
;
6233 Rent
:= RE_Exn_Long_Long_Integer
;
6236 elsif Is_Signed_Integer_Type
(Rtyp
) then
6237 Etyp
:= Standard_Integer
;
6240 Rent
:= RE_Exp_Integer
;
6242 Rent
:= RE_Exn_Integer
;
6245 -- Floating-point cases, always done using Long_Long_Float. We do not
6246 -- need separate routines for the overflow case here, since in the case
6247 -- of floating-point, we generate infinities anyway as a rule (either
6248 -- that or we automatically trap overflow), and if there is an infinity
6249 -- generated and a range check is required, the check will fail anyway.
6252 pragma Assert
(Is_Floating_Point_Type
(Rtyp
));
6253 Etyp
:= Standard_Long_Long_Float
;
6254 Rent
:= RE_Exn_Long_Long_Float
;
6257 -- Common processing for integer cases and floating-point cases.
6258 -- If we are in the right type, we can call runtime routine directly
6261 and then Rtyp
/= Universal_Integer
6262 and then Rtyp
/= Universal_Real
6265 Make_Function_Call
(Loc
,
6266 Name
=> New_Reference_To
(RTE
(Rent
), Loc
),
6267 Parameter_Associations
=> New_List
(Base
, Exp
)));
6269 -- Otherwise we have to introduce conversions (conversions are also
6270 -- required in the universal cases, since the runtime routine is
6271 -- typed using one of the standard types).
6276 Make_Function_Call
(Loc
,
6277 Name
=> New_Reference_To
(RTE
(Rent
), Loc
),
6278 Parameter_Associations
=> New_List
(
6279 Convert_To
(Etyp
, Base
),
6283 Analyze_And_Resolve
(N
, Typ
);
6287 when RE_Not_Available
=>
6289 end Expand_N_Op_Expon
;
6291 --------------------
6292 -- Expand_N_Op_Ge --
6293 --------------------
6295 procedure Expand_N_Op_Ge
(N
: Node_Id
) is
6296 Typ
: constant Entity_Id
:= Etype
(N
);
6297 Op1
: constant Node_Id
:= Left_Opnd
(N
);
6298 Op2
: constant Node_Id
:= Right_Opnd
(N
);
6299 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
6302 Binary_Op_Validity_Checks
(N
);
6304 if Is_Array_Type
(Typ1
) then
6305 Expand_Array_Comparison
(N
);
6309 if Is_Boolean_Type
(Typ1
) then
6310 Adjust_Condition
(Op1
);
6311 Adjust_Condition
(Op2
);
6312 Set_Etype
(N
, Standard_Boolean
);
6313 Adjust_Result_Type
(N
, Typ
);
6316 Rewrite_Comparison
(N
);
6318 -- If we still have comparison, and Vax_Float type, process it
6320 if Vax_Float
(Typ1
) and then Nkind
(N
) in N_Op_Compare
then
6321 Expand_Vax_Comparison
(N
);
6326 --------------------
6327 -- Expand_N_Op_Gt --
6328 --------------------
6330 procedure Expand_N_Op_Gt
(N
: Node_Id
) is
6331 Typ
: constant Entity_Id
:= Etype
(N
);
6332 Op1
: constant Node_Id
:= Left_Opnd
(N
);
6333 Op2
: constant Node_Id
:= Right_Opnd
(N
);
6334 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
6337 Binary_Op_Validity_Checks
(N
);
6339 if Is_Array_Type
(Typ1
) then
6340 Expand_Array_Comparison
(N
);
6344 if Is_Boolean_Type
(Typ1
) then
6345 Adjust_Condition
(Op1
);
6346 Adjust_Condition
(Op2
);
6347 Set_Etype
(N
, Standard_Boolean
);
6348 Adjust_Result_Type
(N
, Typ
);
6351 Rewrite_Comparison
(N
);
6353 -- If we still have comparison, and Vax_Float type, process it
6355 if Vax_Float
(Typ1
) and then Nkind
(N
) in N_Op_Compare
then
6356 Expand_Vax_Comparison
(N
);
6361 --------------------
6362 -- Expand_N_Op_Le --
6363 --------------------
6365 procedure Expand_N_Op_Le
(N
: Node_Id
) is
6366 Typ
: constant Entity_Id
:= Etype
(N
);
6367 Op1
: constant Node_Id
:= Left_Opnd
(N
);
6368 Op2
: constant Node_Id
:= Right_Opnd
(N
);
6369 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
6372 Binary_Op_Validity_Checks
(N
);
6374 if Is_Array_Type
(Typ1
) then
6375 Expand_Array_Comparison
(N
);
6379 if Is_Boolean_Type
(Typ1
) then
6380 Adjust_Condition
(Op1
);
6381 Adjust_Condition
(Op2
);
6382 Set_Etype
(N
, Standard_Boolean
);
6383 Adjust_Result_Type
(N
, Typ
);
6386 Rewrite_Comparison
(N
);
6388 -- If we still have comparison, and Vax_Float type, process it
6390 if Vax_Float
(Typ1
) and then Nkind
(N
) in N_Op_Compare
then
6391 Expand_Vax_Comparison
(N
);
6396 --------------------
6397 -- Expand_N_Op_Lt --
6398 --------------------
6400 procedure Expand_N_Op_Lt
(N
: Node_Id
) is
6401 Typ
: constant Entity_Id
:= Etype
(N
);
6402 Op1
: constant Node_Id
:= Left_Opnd
(N
);
6403 Op2
: constant Node_Id
:= Right_Opnd
(N
);
6404 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
6407 Binary_Op_Validity_Checks
(N
);
6409 if Is_Array_Type
(Typ1
) then
6410 Expand_Array_Comparison
(N
);
6414 if Is_Boolean_Type
(Typ1
) then
6415 Adjust_Condition
(Op1
);
6416 Adjust_Condition
(Op2
);
6417 Set_Etype
(N
, Standard_Boolean
);
6418 Adjust_Result_Type
(N
, Typ
);
6421 Rewrite_Comparison
(N
);
6423 -- If we still have comparison, and Vax_Float type, process it
6425 if Vax_Float
(Typ1
) and then Nkind
(N
) in N_Op_Compare
then
6426 Expand_Vax_Comparison
(N
);
6431 -----------------------
6432 -- Expand_N_Op_Minus --
6433 -----------------------
6435 procedure Expand_N_Op_Minus
(N
: Node_Id
) is
6436 Loc
: constant Source_Ptr
:= Sloc
(N
);
6437 Typ
: constant Entity_Id
:= Etype
(N
);
6440 Unary_Op_Validity_Checks
(N
);
6442 if not Backend_Overflow_Checks_On_Target
6443 and then Is_Signed_Integer_Type
(Etype
(N
))
6444 and then Do_Overflow_Check
(N
)
6446 -- Software overflow checking expands -expr into (0 - expr)
6449 Make_Op_Subtract
(Loc
,
6450 Left_Opnd
=> Make_Integer_Literal
(Loc
, 0),
6451 Right_Opnd
=> Right_Opnd
(N
)));
6453 Analyze_And_Resolve
(N
, Typ
);
6455 -- Vax floating-point types case
6457 elsif Vax_Float
(Etype
(N
)) then
6458 Expand_Vax_Arith
(N
);
6460 end Expand_N_Op_Minus
;
6462 ---------------------
6463 -- Expand_N_Op_Mod --
6464 ---------------------
6466 procedure Expand_N_Op_Mod
(N
: Node_Id
) is
6467 Loc
: constant Source_Ptr
:= Sloc
(N
);
6468 Typ
: constant Entity_Id
:= Etype
(N
);
6469 Left
: constant Node_Id
:= Left_Opnd
(N
);
6470 Right
: constant Node_Id
:= Right_Opnd
(N
);
6471 DOC
: constant Boolean := Do_Overflow_Check
(N
);
6472 DDC
: constant Boolean := Do_Division_Check
(N
);
6482 pragma Warnings
(Off
, Lhi
);
6485 Binary_Op_Validity_Checks
(N
);
6487 Determine_Range
(Right
, ROK
, Rlo
, Rhi
, Assume_Valid
=> True);
6488 Determine_Range
(Left
, LOK
, Llo
, Lhi
, Assume_Valid
=> True);
6490 -- Convert mod to rem if operands are known non-negative. We do this
6491 -- since it is quite likely that this will improve the quality of code,
6492 -- (the operation now corresponds to the hardware remainder), and it
6493 -- does not seem likely that it could be harmful.
6495 if LOK
and then Llo
>= 0
6497 ROK
and then Rlo
>= 0
6500 Make_Op_Rem
(Sloc
(N
),
6501 Left_Opnd
=> Left_Opnd
(N
),
6502 Right_Opnd
=> Right_Opnd
(N
)));
6504 -- Instead of reanalyzing the node we do the analysis manually. This
6505 -- avoids anomalies when the replacement is done in an instance and
6506 -- is epsilon more efficient.
6508 Set_Entity
(N
, Standard_Entity
(S_Op_Rem
));
6510 Set_Do_Overflow_Check
(N
, DOC
);
6511 Set_Do_Division_Check
(N
, DDC
);
6512 Expand_N_Op_Rem
(N
);
6515 -- Otherwise, normal mod processing
6518 if Is_Integer_Type
(Etype
(N
)) then
6519 Apply_Divide_Check
(N
);
6522 -- Apply optimization x mod 1 = 0. We don't really need that with
6523 -- gcc, but it is useful with other back ends (e.g. AAMP), and is
6524 -- certainly harmless.
6526 if Is_Integer_Type
(Etype
(N
))
6527 and then Compile_Time_Known_Value
(Right
)
6528 and then Expr_Value
(Right
) = Uint_1
6530 -- Call Remove_Side_Effects to ensure that any side effects in
6531 -- the ignored left operand (in particular function calls to
6532 -- user defined functions) are properly executed.
6534 Remove_Side_Effects
(Left
);
6536 Rewrite
(N
, Make_Integer_Literal
(Loc
, 0));
6537 Analyze_And_Resolve
(N
, Typ
);
6541 -- Deal with annoying case of largest negative number remainder
6542 -- minus one. Gigi does not handle this case correctly, because
6543 -- it generates a divide instruction which may trap in this case.
6545 -- In fact the check is quite easy, if the right operand is -1, then
6546 -- the mod value is always 0, and we can just ignore the left operand
6547 -- completely in this case.
6549 -- The operand type may be private (e.g. in the expansion of an
6550 -- intrinsic operation) so we must use the underlying type to get the
6551 -- bounds, and convert the literals explicitly.
6555 (Type_Low_Bound
(Base_Type
(Underlying_Type
(Etype
(Left
)))));
6557 if ((not ROK
) or else (Rlo
<= (-1) and then (-1) <= Rhi
))
6559 ((not LOK
) or else (Llo
= LLB
))
6562 Make_Conditional_Expression
(Loc
,
6563 Expressions
=> New_List
(
6565 Left_Opnd
=> Duplicate_Subexpr
(Right
),
6567 Unchecked_Convert_To
(Typ
,
6568 Make_Integer_Literal
(Loc
, -1))),
6569 Unchecked_Convert_To
(Typ
,
6570 Make_Integer_Literal
(Loc
, Uint_0
)),
6571 Relocate_Node
(N
))));
6573 Set_Analyzed
(Next
(Next
(First
(Expressions
(N
)))));
6574 Analyze_And_Resolve
(N
, Typ
);
6577 end Expand_N_Op_Mod
;
6579 --------------------------
6580 -- Expand_N_Op_Multiply --
6581 --------------------------
6583 procedure Expand_N_Op_Multiply
(N
: Node_Id
) is
6584 Loc
: constant Source_Ptr
:= Sloc
(N
);
6585 Lop
: constant Node_Id
:= Left_Opnd
(N
);
6586 Rop
: constant Node_Id
:= Right_Opnd
(N
);
6588 Lp2
: constant Boolean :=
6589 Nkind
(Lop
) = N_Op_Expon
6590 and then Is_Power_Of_2_For_Shift
(Lop
);
6592 Rp2
: constant Boolean :=
6593 Nkind
(Rop
) = N_Op_Expon
6594 and then Is_Power_Of_2_For_Shift
(Rop
);
6596 Ltyp
: constant Entity_Id
:= Etype
(Lop
);
6597 Rtyp
: constant Entity_Id
:= Etype
(Rop
);
6598 Typ
: Entity_Id
:= Etype
(N
);
6601 Binary_Op_Validity_Checks
(N
);
6603 -- Special optimizations for integer types
6605 if Is_Integer_Type
(Typ
) then
6607 -- N * 0 = 0 for integer types
6609 if Compile_Time_Known_Value
(Rop
)
6610 and then Expr_Value
(Rop
) = Uint_0
6612 -- Call Remove_Side_Effects to ensure that any side effects in
6613 -- the ignored left operand (in particular function calls to
6614 -- user defined functions) are properly executed.
6616 Remove_Side_Effects
(Lop
);
6618 Rewrite
(N
, Make_Integer_Literal
(Loc
, Uint_0
));
6619 Analyze_And_Resolve
(N
, Typ
);
6623 -- Similar handling for 0 * N = 0
6625 if Compile_Time_Known_Value
(Lop
)
6626 and then Expr_Value
(Lop
) = Uint_0
6628 Remove_Side_Effects
(Rop
);
6629 Rewrite
(N
, Make_Integer_Literal
(Loc
, Uint_0
));
6630 Analyze_And_Resolve
(N
, Typ
);
6634 -- N * 1 = 1 * N = N for integer types
6636 -- This optimisation is not done if we are going to
6637 -- rewrite the product 1 * 2 ** N to a shift.
6639 if Compile_Time_Known_Value
(Rop
)
6640 and then Expr_Value
(Rop
) = Uint_1
6646 elsif Compile_Time_Known_Value
(Lop
)
6647 and then Expr_Value
(Lop
) = Uint_1
6655 -- Convert x * 2 ** y to Shift_Left (x, y). Note that the fact that
6656 -- Is_Power_Of_2_For_Shift is set means that we know that our left
6657 -- operand is an integer, as required for this to work.
6662 -- Convert 2 ** A * 2 ** B into 2 ** (A + B)
6666 Left_Opnd
=> Make_Integer_Literal
(Loc
, 2),
6669 Left_Opnd
=> Right_Opnd
(Lop
),
6670 Right_Opnd
=> Right_Opnd
(Rop
))));
6671 Analyze_And_Resolve
(N
, Typ
);
6676 Make_Op_Shift_Left
(Loc
,
6679 Convert_To
(Standard_Natural
, Right_Opnd
(Rop
))));
6680 Analyze_And_Resolve
(N
, Typ
);
6684 -- Same processing for the operands the other way round
6688 Make_Op_Shift_Left
(Loc
,
6691 Convert_To
(Standard_Natural
, Right_Opnd
(Lop
))));
6692 Analyze_And_Resolve
(N
, Typ
);
6696 -- Do required fixup of universal fixed operation
6698 if Typ
= Universal_Fixed
then
6699 Fixup_Universal_Fixed_Operation
(N
);
6703 -- Multiplications with fixed-point results
6705 if Is_Fixed_Point_Type
(Typ
) then
6707 -- No special processing if Treat_Fixed_As_Integer is set, since from
6708 -- a semantic point of view such operations are simply integer
6709 -- operations and will be treated that way.
6711 if not Treat_Fixed_As_Integer
(N
) then
6713 -- Case of fixed * integer => fixed
6715 if Is_Integer_Type
(Rtyp
) then
6716 Expand_Multiply_Fixed_By_Integer_Giving_Fixed
(N
);
6718 -- Case of integer * fixed => fixed
6720 elsif Is_Integer_Type
(Ltyp
) then
6721 Expand_Multiply_Integer_By_Fixed_Giving_Fixed
(N
);
6723 -- Case of fixed * fixed => fixed
6726 Expand_Multiply_Fixed_By_Fixed_Giving_Fixed
(N
);
6730 -- Other cases of multiplication of fixed-point operands. Again we
6731 -- exclude the cases where Treat_Fixed_As_Integer flag is set.
6733 elsif (Is_Fixed_Point_Type
(Ltyp
) or else Is_Fixed_Point_Type
(Rtyp
))
6734 and then not Treat_Fixed_As_Integer
(N
)
6736 if Is_Integer_Type
(Typ
) then
6737 Expand_Multiply_Fixed_By_Fixed_Giving_Integer
(N
);
6739 pragma Assert
(Is_Floating_Point_Type
(Typ
));
6740 Expand_Multiply_Fixed_By_Fixed_Giving_Float
(N
);
6743 -- Mixed-mode operations can appear in a non-static universal context,
6744 -- in which case the integer argument must be converted explicitly.
6746 elsif Typ
= Universal_Real
6747 and then Is_Integer_Type
(Rtyp
)
6749 Rewrite
(Rop
, Convert_To
(Universal_Real
, Relocate_Node
(Rop
)));
6751 Analyze_And_Resolve
(Rop
, Universal_Real
);
6753 elsif Typ
= Universal_Real
6754 and then Is_Integer_Type
(Ltyp
)
6756 Rewrite
(Lop
, Convert_To
(Universal_Real
, Relocate_Node
(Lop
)));
6758 Analyze_And_Resolve
(Lop
, Universal_Real
);
6760 -- Non-fixed point cases, check software overflow checking required
6762 elsif Is_Signed_Integer_Type
(Etype
(N
)) then
6763 Apply_Arithmetic_Overflow_Check
(N
);
6765 -- Deal with VAX float case
6767 elsif Vax_Float
(Typ
) then
6768 Expand_Vax_Arith
(N
);
6771 end Expand_N_Op_Multiply
;
6773 --------------------
6774 -- Expand_N_Op_Ne --
6775 --------------------
6777 procedure Expand_N_Op_Ne
(N
: Node_Id
) is
6778 Typ
: constant Entity_Id
:= Etype
(Left_Opnd
(N
));
6781 -- Case of elementary type with standard operator
6783 if Is_Elementary_Type
(Typ
)
6784 and then Sloc
(Entity
(N
)) = Standard_Location
6786 Binary_Op_Validity_Checks
(N
);
6788 -- Boolean types (requiring handling of non-standard case)
6790 if Is_Boolean_Type
(Typ
) then
6791 Adjust_Condition
(Left_Opnd
(N
));
6792 Adjust_Condition
(Right_Opnd
(N
));
6793 Set_Etype
(N
, Standard_Boolean
);
6794 Adjust_Result_Type
(N
, Typ
);
6797 Rewrite_Comparison
(N
);
6799 -- If we still have comparison for Vax_Float, process it
6801 if Vax_Float
(Typ
) and then Nkind
(N
) in N_Op_Compare
then
6802 Expand_Vax_Comparison
(N
);
6806 -- For all cases other than elementary types, we rewrite node as the
6807 -- negation of an equality operation, and reanalyze. The equality to be
6808 -- used is defined in the same scope and has the same signature. This
6809 -- signature must be set explicitly since in an instance it may not have
6810 -- the same visibility as in the generic unit. This avoids duplicating
6811 -- or factoring the complex code for record/array equality tests etc.
6815 Loc
: constant Source_Ptr
:= Sloc
(N
);
6817 Ne
: constant Entity_Id
:= Entity
(N
);
6820 Binary_Op_Validity_Checks
(N
);
6826 Left_Opnd
=> Left_Opnd
(N
),
6827 Right_Opnd
=> Right_Opnd
(N
)));
6828 Set_Paren_Count
(Right_Opnd
(Neg
), 1);
6830 if Scope
(Ne
) /= Standard_Standard
then
6831 Set_Entity
(Right_Opnd
(Neg
), Corresponding_Equality
(Ne
));
6834 -- For navigation purposes, the inequality is treated as an
6835 -- implicit reference to the corresponding equality. Preserve the
6836 -- Comes_From_ source flag so that the proper Xref entry is
6839 Preserve_Comes_From_Source
(Neg
, N
);
6840 Preserve_Comes_From_Source
(Right_Opnd
(Neg
), N
);
6842 Analyze_And_Resolve
(N
, Standard_Boolean
);
6847 ---------------------
6848 -- Expand_N_Op_Not --
6849 ---------------------
6851 -- If the argument is other than a Boolean array type, there is no special
6852 -- expansion required, except for VMS operations on signed integers.
6854 -- For the packed case, we call the special routine in Exp_Pakd, except
6855 -- that if the component size is greater than one, we use the standard
6856 -- routine generating a gruesome loop (it is so peculiar to have packed
6857 -- arrays with non-standard Boolean representations anyway, so it does not
6858 -- matter that we do not handle this case efficiently).
6860 -- For the unpacked case (and for the special packed case where we have non
6861 -- standard Booleans, as discussed above), we generate and insert into the
6862 -- tree the following function definition:
6864 -- function Nnnn (A : arr) is
6867 -- for J in a'range loop
6868 -- B (J) := not A (J);
6873 -- Here arr is the actual subtype of the parameter (and hence always
6874 -- constrained). Then we replace the not with a call to this function.
6876 procedure Expand_N_Op_Not
(N
: Node_Id
) is
6877 Loc
: constant Source_Ptr
:= Sloc
(N
);
6878 Typ
: constant Entity_Id
:= Etype
(N
);
6887 Func_Name
: Entity_Id
;
6888 Loop_Statement
: Node_Id
;
6891 Unary_Op_Validity_Checks
(N
);
6893 -- For boolean operand, deal with non-standard booleans
6895 if Is_Boolean_Type
(Typ
) then
6896 Adjust_Condition
(Right_Opnd
(N
));
6897 Set_Etype
(N
, Standard_Boolean
);
6898 Adjust_Result_Type
(N
, Typ
);
6902 -- For the VMS "not" on signed integer types, use conversion to and
6903 -- from a predefined modular type.
6905 if Is_VMS_Operator
(Entity
(N
)) then
6911 -- If this is a derived type, retrieve original VMS type so that
6912 -- the proper sized type is used for intermediate values.
6914 if Is_Derived_Type
(Typ
) then
6915 Rtyp
:= First_Subtype
(Etype
(Typ
));
6920 -- The proper unsigned type must have a size compatible with
6921 -- the operand, to prevent misalignment..
6923 if RM_Size
(Rtyp
) <= 8 then
6924 Utyp
:= RTE
(RE_Unsigned_8
);
6926 elsif RM_Size
(Rtyp
) <= 16 then
6927 Utyp
:= RTE
(RE_Unsigned_16
);
6929 elsif RM_Size
(Rtyp
) = RM_Size
(Standard_Unsigned
) then
6930 Utyp
:= RTE
(RE_Unsigned_32
);
6933 Utyp
:= RTE
(RE_Long_Long_Unsigned
);
6937 Unchecked_Convert_To
(Typ
,
6939 Unchecked_Convert_To
(Utyp
, Right_Opnd
(N
)))));
6940 Analyze_And_Resolve
(N
, Typ
);
6945 -- Only array types need any other processing
6947 if not Is_Array_Type
(Typ
) then
6951 -- Case of array operand. If bit packed with a component size of 1,
6952 -- handle it in Exp_Pakd if the operand is known to be aligned.
6954 if Is_Bit_Packed_Array
(Typ
)
6955 and then Component_Size
(Typ
) = 1
6956 and then not Is_Possibly_Unaligned_Object
(Right_Opnd
(N
))
6958 Expand_Packed_Not
(N
);
6962 -- Case of array operand which is not bit-packed. If the context is
6963 -- a safe assignment, call in-place operation, If context is a larger
6964 -- boolean expression in the context of a safe assignment, expansion is
6965 -- done by enclosing operation.
6967 Opnd
:= Relocate_Node
(Right_Opnd
(N
));
6968 Convert_To_Actual_Subtype
(Opnd
);
6969 Arr
:= Etype
(Opnd
);
6970 Ensure_Defined
(Arr
, N
);
6971 Silly_Boolean_Array_Not_Test
(N
, Arr
);
6973 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
6974 if Safe_In_Place_Array_Op
(Name
(Parent
(N
)), N
, Empty
) then
6975 Build_Boolean_Array_Proc_Call
(Parent
(N
), Opnd
, Empty
);
6978 -- Special case the negation of a binary operation
6980 elsif Nkind_In
(Opnd
, N_Op_And
, N_Op_Or
, N_Op_Xor
)
6981 and then Safe_In_Place_Array_Op
6982 (Name
(Parent
(N
)), Left_Opnd
(Opnd
), Right_Opnd
(Opnd
))
6984 Build_Boolean_Array_Proc_Call
(Parent
(N
), Opnd
, Empty
);
6988 elsif Nkind
(Parent
(N
)) in N_Binary_Op
6989 and then Nkind
(Parent
(Parent
(N
))) = N_Assignment_Statement
6992 Op1
: constant Node_Id
:= Left_Opnd
(Parent
(N
));
6993 Op2
: constant Node_Id
:= Right_Opnd
(Parent
(N
));
6994 Lhs
: constant Node_Id
:= Name
(Parent
(Parent
(N
)));
6997 if Safe_In_Place_Array_Op
(Lhs
, Op1
, Op2
) then
6999 and then Nkind
(Op2
) = N_Op_Not
7001 -- (not A) op (not B) can be reduced to a single call
7006 and then Nkind
(Parent
(N
)) = N_Op_Xor
7008 -- A xor (not B) can also be special-cased
7016 A
:= Make_Defining_Identifier
(Loc
, Name_uA
);
7017 B
:= Make_Defining_Identifier
(Loc
, Name_uB
);
7018 J
:= Make_Defining_Identifier
(Loc
, Name_uJ
);
7021 Make_Indexed_Component
(Loc
,
7022 Prefix
=> New_Reference_To
(A
, Loc
),
7023 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)));
7026 Make_Indexed_Component
(Loc
,
7027 Prefix
=> New_Reference_To
(B
, Loc
),
7028 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)));
7031 Make_Implicit_Loop_Statement
(N
,
7032 Identifier
=> Empty
,
7035 Make_Iteration_Scheme
(Loc
,
7036 Loop_Parameter_Specification
=>
7037 Make_Loop_Parameter_Specification
(Loc
,
7038 Defining_Identifier
=> J
,
7039 Discrete_Subtype_Definition
=>
7040 Make_Attribute_Reference
(Loc
,
7041 Prefix
=> Make_Identifier
(Loc
, Chars
(A
)),
7042 Attribute_Name
=> Name_Range
))),
7044 Statements
=> New_List
(
7045 Make_Assignment_Statement
(Loc
,
7047 Expression
=> Make_Op_Not
(Loc
, A_J
))));
7049 Func_Name
:= Make_Temporary
(Loc
, 'N');
7050 Set_Is_Inlined
(Func_Name
);
7053 Make_Subprogram_Body
(Loc
,
7055 Make_Function_Specification
(Loc
,
7056 Defining_Unit_Name
=> Func_Name
,
7057 Parameter_Specifications
=> New_List
(
7058 Make_Parameter_Specification
(Loc
,
7059 Defining_Identifier
=> A
,
7060 Parameter_Type
=> New_Reference_To
(Typ
, Loc
))),
7061 Result_Definition
=> New_Reference_To
(Typ
, Loc
)),
7063 Declarations
=> New_List
(
7064 Make_Object_Declaration
(Loc
,
7065 Defining_Identifier
=> B
,
7066 Object_Definition
=> New_Reference_To
(Arr
, Loc
))),
7068 Handled_Statement_Sequence
=>
7069 Make_Handled_Sequence_Of_Statements
(Loc
,
7070 Statements
=> New_List
(
7072 Make_Simple_Return_Statement
(Loc
,
7074 Make_Identifier
(Loc
, Chars
(B
)))))));
7077 Make_Function_Call
(Loc
,
7078 Name
=> New_Reference_To
(Func_Name
, Loc
),
7079 Parameter_Associations
=> New_List
(Opnd
)));
7081 Analyze_And_Resolve
(N
, Typ
);
7082 end Expand_N_Op_Not
;
7084 --------------------
7085 -- Expand_N_Op_Or --
7086 --------------------
7088 procedure Expand_N_Op_Or
(N
: Node_Id
) is
7089 Typ
: constant Entity_Id
:= Etype
(N
);
7092 Binary_Op_Validity_Checks
(N
);
7094 if Is_Array_Type
(Etype
(N
)) then
7095 Expand_Boolean_Operator
(N
);
7097 elsif Is_Boolean_Type
(Etype
(N
)) then
7099 -- Replace OR by OR ELSE if Short_Circuit_And_Or active and the
7100 -- type is standard Boolean (do not mess with AND that uses a non-
7101 -- standard Boolean type, because something strange is going on).
7103 if Short_Circuit_And_Or
and then Typ
= Standard_Boolean
then
7105 Make_Or_Else
(Sloc
(N
),
7106 Left_Opnd
=> Relocate_Node
(Left_Opnd
(N
)),
7107 Right_Opnd
=> Relocate_Node
(Right_Opnd
(N
))));
7108 Analyze_And_Resolve
(N
, Typ
);
7110 -- Otherwise, adjust conditions
7113 Adjust_Condition
(Left_Opnd
(N
));
7114 Adjust_Condition
(Right_Opnd
(N
));
7115 Set_Etype
(N
, Standard_Boolean
);
7116 Adjust_Result_Type
(N
, Typ
);
7121 ----------------------
7122 -- Expand_N_Op_Plus --
7123 ----------------------
7125 procedure Expand_N_Op_Plus
(N
: Node_Id
) is
7127 Unary_Op_Validity_Checks
(N
);
7128 end Expand_N_Op_Plus
;
7130 ---------------------
7131 -- Expand_N_Op_Rem --
7132 ---------------------
7134 procedure Expand_N_Op_Rem
(N
: Node_Id
) is
7135 Loc
: constant Source_Ptr
:= Sloc
(N
);
7136 Typ
: constant Entity_Id
:= Etype
(N
);
7138 Left
: constant Node_Id
:= Left_Opnd
(N
);
7139 Right
: constant Node_Id
:= Right_Opnd
(N
);
7147 -- Set if corresponding operand can be negative
7149 pragma Unreferenced
(Hi
);
7152 Binary_Op_Validity_Checks
(N
);
7154 if Is_Integer_Type
(Etype
(N
)) then
7155 Apply_Divide_Check
(N
);
7158 -- Apply optimization x rem 1 = 0. We don't really need that with gcc,
7159 -- but it is useful with other back ends (e.g. AAMP), and is certainly
7162 if Is_Integer_Type
(Etype
(N
))
7163 and then Compile_Time_Known_Value
(Right
)
7164 and then Expr_Value
(Right
) = Uint_1
7166 -- Call Remove_Side_Effects to ensure that any side effects in the
7167 -- ignored left operand (in particular function calls to user defined
7168 -- functions) are properly executed.
7170 Remove_Side_Effects
(Left
);
7172 Rewrite
(N
, Make_Integer_Literal
(Loc
, 0));
7173 Analyze_And_Resolve
(N
, Typ
);
7177 -- Deal with annoying case of largest negative number remainder minus
7178 -- one. Gigi does not handle this case correctly, because it generates
7179 -- a divide instruction which may trap in this case.
7181 -- In fact the check is quite easy, if the right operand is -1, then
7182 -- the remainder is always 0, and we can just ignore the left operand
7183 -- completely in this case.
7185 Determine_Range
(Right
, OK
, Lo
, Hi
, Assume_Valid
=> True);
7186 Lneg
:= (not OK
) or else Lo
< 0;
7188 Determine_Range
(Left
, OK
, Lo
, Hi
, Assume_Valid
=> True);
7189 Rneg
:= (not OK
) or else Lo
< 0;
7191 -- We won't mess with trying to find out if the left operand can really
7192 -- be the largest negative number (that's a pain in the case of private
7193 -- types and this is really marginal). We will just assume that we need
7194 -- the test if the left operand can be negative at all.
7196 if Lneg
and Rneg
then
7198 Make_Conditional_Expression
(Loc
,
7199 Expressions
=> New_List
(
7201 Left_Opnd
=> Duplicate_Subexpr
(Right
),
7203 Unchecked_Convert_To
(Typ
,
7204 Make_Integer_Literal
(Loc
, -1))),
7206 Unchecked_Convert_To
(Typ
,
7207 Make_Integer_Literal
(Loc
, Uint_0
)),
7209 Relocate_Node
(N
))));
7211 Set_Analyzed
(Next
(Next
(First
(Expressions
(N
)))));
7212 Analyze_And_Resolve
(N
, Typ
);
7214 end Expand_N_Op_Rem
;
7216 -----------------------------
7217 -- Expand_N_Op_Rotate_Left --
7218 -----------------------------
7220 procedure Expand_N_Op_Rotate_Left
(N
: Node_Id
) is
7222 Binary_Op_Validity_Checks
(N
);
7223 end Expand_N_Op_Rotate_Left
;
7225 ------------------------------
7226 -- Expand_N_Op_Rotate_Right --
7227 ------------------------------
7229 procedure Expand_N_Op_Rotate_Right
(N
: Node_Id
) is
7231 Binary_Op_Validity_Checks
(N
);
7232 end Expand_N_Op_Rotate_Right
;
7234 ----------------------------
7235 -- Expand_N_Op_Shift_Left --
7236 ----------------------------
7238 procedure Expand_N_Op_Shift_Left
(N
: Node_Id
) is
7240 Binary_Op_Validity_Checks
(N
);
7241 end Expand_N_Op_Shift_Left
;
7243 -----------------------------
7244 -- Expand_N_Op_Shift_Right --
7245 -----------------------------
7247 procedure Expand_N_Op_Shift_Right
(N
: Node_Id
) is
7249 Binary_Op_Validity_Checks
(N
);
7250 end Expand_N_Op_Shift_Right
;
7252 ----------------------------------------
7253 -- Expand_N_Op_Shift_Right_Arithmetic --
7254 ----------------------------------------
7256 procedure Expand_N_Op_Shift_Right_Arithmetic
(N
: Node_Id
) is
7258 Binary_Op_Validity_Checks
(N
);
7259 end Expand_N_Op_Shift_Right_Arithmetic
;
7261 --------------------------
7262 -- Expand_N_Op_Subtract --
7263 --------------------------
7265 procedure Expand_N_Op_Subtract
(N
: Node_Id
) is
7266 Typ
: constant Entity_Id
:= Etype
(N
);
7269 Binary_Op_Validity_Checks
(N
);
7271 -- N - 0 = N for integer types
7273 if Is_Integer_Type
(Typ
)
7274 and then Compile_Time_Known_Value
(Right_Opnd
(N
))
7275 and then Expr_Value
(Right_Opnd
(N
)) = 0
7277 Rewrite
(N
, Left_Opnd
(N
));
7281 -- Arithmetic overflow checks for signed integer/fixed point types
7283 if Is_Signed_Integer_Type
(Typ
)
7284 or else Is_Fixed_Point_Type
(Typ
)
7286 Apply_Arithmetic_Overflow_Check
(N
);
7288 -- Vax floating-point types case
7290 elsif Vax_Float
(Typ
) then
7291 Expand_Vax_Arith
(N
);
7293 end Expand_N_Op_Subtract
;
7295 ---------------------
7296 -- Expand_N_Op_Xor --
7297 ---------------------
7299 procedure Expand_N_Op_Xor
(N
: Node_Id
) is
7300 Typ
: constant Entity_Id
:= Etype
(N
);
7303 Binary_Op_Validity_Checks
(N
);
7305 if Is_Array_Type
(Etype
(N
)) then
7306 Expand_Boolean_Operator
(N
);
7308 elsif Is_Boolean_Type
(Etype
(N
)) then
7309 Adjust_Condition
(Left_Opnd
(N
));
7310 Adjust_Condition
(Right_Opnd
(N
));
7311 Set_Etype
(N
, Standard_Boolean
);
7312 Adjust_Result_Type
(N
, Typ
);
7314 end Expand_N_Op_Xor
;
7316 ----------------------
7317 -- Expand_N_Or_Else --
7318 ----------------------
7320 procedure Expand_N_Or_Else
(N
: Node_Id
)
7321 renames Expand_Short_Circuit_Operator
;
7323 -----------------------------------
7324 -- Expand_N_Qualified_Expression --
7325 -----------------------------------
7327 procedure Expand_N_Qualified_Expression
(N
: Node_Id
) is
7328 Operand
: constant Node_Id
:= Expression
(N
);
7329 Target_Type
: constant Entity_Id
:= Entity
(Subtype_Mark
(N
));
7332 -- Do validity check if validity checking operands
7334 if Validity_Checks_On
7335 and then Validity_Check_Operands
7337 Ensure_Valid
(Operand
);
7340 -- Apply possible constraint check
7342 Apply_Constraint_Check
(Operand
, Target_Type
, No_Sliding
=> True);
7344 if Do_Range_Check
(Operand
) then
7345 Set_Do_Range_Check
(Operand
, False);
7346 Generate_Range_Check
(Operand
, Target_Type
, CE_Range_Check_Failed
);
7348 end Expand_N_Qualified_Expression
;
7350 ---------------------------------
7351 -- Expand_N_Selected_Component --
7352 ---------------------------------
7354 -- If the selector is a discriminant of a concurrent object, rewrite the
7355 -- prefix to denote the corresponding record type.
7357 procedure Expand_N_Selected_Component
(N
: Node_Id
) is
7358 Loc
: constant Source_Ptr
:= Sloc
(N
);
7359 Par
: constant Node_Id
:= Parent
(N
);
7360 P
: constant Node_Id
:= Prefix
(N
);
7361 Ptyp
: Entity_Id
:= Underlying_Type
(Etype
(P
));
7366 function In_Left_Hand_Side
(Comp
: Node_Id
) return Boolean;
7367 -- Gigi needs a temporary for prefixes that depend on a discriminant,
7368 -- unless the context of an assignment can provide size information.
7369 -- Don't we have a general routine that does this???
7371 -----------------------
7372 -- In_Left_Hand_Side --
7373 -----------------------
7375 function In_Left_Hand_Side
(Comp
: Node_Id
) return Boolean is
7377 return (Nkind
(Parent
(Comp
)) = N_Assignment_Statement
7378 and then Comp
= Name
(Parent
(Comp
)))
7379 or else (Present
(Parent
(Comp
))
7380 and then Nkind
(Parent
(Comp
)) in N_Subexpr
7381 and then In_Left_Hand_Side
(Parent
(Comp
)));
7382 end In_Left_Hand_Side
;
7384 -- Start of processing for Expand_N_Selected_Component
7387 -- Insert explicit dereference if required
7389 if Is_Access_Type
(Ptyp
) then
7390 Insert_Explicit_Dereference
(P
);
7391 Analyze_And_Resolve
(P
, Designated_Type
(Ptyp
));
7393 if Ekind
(Etype
(P
)) = E_Private_Subtype
7394 and then Is_For_Access_Subtype
(Etype
(P
))
7396 Set_Etype
(P
, Base_Type
(Etype
(P
)));
7402 -- Deal with discriminant check required
7404 if Do_Discriminant_Check
(N
) then
7406 -- Present the discriminant checking function to the backend, so that
7407 -- it can inline the call to the function.
7410 (Discriminant_Checking_Func
7411 (Original_Record_Component
(Entity
(Selector_Name
(N
)))));
7413 -- Now reset the flag and generate the call
7415 Set_Do_Discriminant_Check
(N
, False);
7416 Generate_Discriminant_Check
(N
);
7419 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
7420 -- function, then additional actuals must be passed.
7422 if Ada_Version
>= Ada_05
7423 and then Is_Build_In_Place_Function_Call
(P
)
7425 Make_Build_In_Place_Call_In_Anonymous_Context
(P
);
7428 -- Gigi cannot handle unchecked conversions that are the prefix of a
7429 -- selected component with discriminants. This must be checked during
7430 -- expansion, because during analysis the type of the selector is not
7431 -- known at the point the prefix is analyzed. If the conversion is the
7432 -- target of an assignment, then we cannot force the evaluation.
7434 if Nkind
(Prefix
(N
)) = N_Unchecked_Type_Conversion
7435 and then Has_Discriminants
(Etype
(N
))
7436 and then not In_Left_Hand_Side
(N
)
7438 Force_Evaluation
(Prefix
(N
));
7441 -- Remaining processing applies only if selector is a discriminant
7443 if Ekind
(Entity
(Selector_Name
(N
))) = E_Discriminant
then
7445 -- If the selector is a discriminant of a constrained record type,
7446 -- we may be able to rewrite the expression with the actual value
7447 -- of the discriminant, a useful optimization in some cases.
7449 if Is_Record_Type
(Ptyp
)
7450 and then Has_Discriminants
(Ptyp
)
7451 and then Is_Constrained
(Ptyp
)
7453 -- Do this optimization for discrete types only, and not for
7454 -- access types (access discriminants get us into trouble!)
7456 if not Is_Discrete_Type
(Etype
(N
)) then
7459 -- Don't do this on the left hand of an assignment statement.
7460 -- Normally one would think that references like this would
7461 -- not occur, but they do in generated code, and mean that
7462 -- we really do want to assign the discriminant!
7464 elsif Nkind
(Par
) = N_Assignment_Statement
7465 and then Name
(Par
) = N
7469 -- Don't do this optimization for the prefix of an attribute or
7470 -- the operand of an object renaming declaration since these are
7471 -- contexts where we do not want the value anyway.
7473 elsif (Nkind
(Par
) = N_Attribute_Reference
7474 and then Prefix
(Par
) = N
)
7475 or else Is_Renamed_Object
(N
)
7479 -- Don't do this optimization if we are within the code for a
7480 -- discriminant check, since the whole point of such a check may
7481 -- be to verify the condition on which the code below depends!
7483 elsif Is_In_Discriminant_Check
(N
) then
7486 -- Green light to see if we can do the optimization. There is
7487 -- still one condition that inhibits the optimization below but
7488 -- now is the time to check the particular discriminant.
7491 -- Loop through discriminants to find the matching discriminant
7492 -- constraint to see if we can copy it.
7494 Disc
:= First_Discriminant
(Ptyp
);
7495 Dcon
:= First_Elmt
(Discriminant_Constraint
(Ptyp
));
7496 Discr_Loop
: while Present
(Dcon
) loop
7498 -- Check if this is the matching discriminant
7500 if Disc
= Entity
(Selector_Name
(N
)) then
7502 -- Here we have the matching discriminant. Check for
7503 -- the case of a discriminant of a component that is
7504 -- constrained by an outer discriminant, which cannot
7505 -- be optimized away.
7508 Denotes_Discriminant
7509 (Node
(Dcon
), Check_Concurrent
=> True)
7513 -- In the context of a case statement, the expression may
7514 -- have the base type of the discriminant, and we need to
7515 -- preserve the constraint to avoid spurious errors on
7518 elsif Nkind
(Parent
(N
)) = N_Case_Statement
7519 and then Etype
(Node
(Dcon
)) /= Etype
(Disc
)
7522 Make_Qualified_Expression
(Loc
,
7524 New_Occurrence_Of
(Etype
(Disc
), Loc
),
7526 New_Copy_Tree
(Node
(Dcon
))));
7527 Analyze_And_Resolve
(N
, Etype
(Disc
));
7529 -- In case that comes out as a static expression,
7530 -- reset it (a selected component is never static).
7532 Set_Is_Static_Expression
(N
, False);
7535 -- Otherwise we can just copy the constraint, but the
7536 -- result is certainly not static! In some cases the
7537 -- discriminant constraint has been analyzed in the
7538 -- context of the original subtype indication, but for
7539 -- itypes the constraint might not have been analyzed
7540 -- yet, and this must be done now.
7543 Rewrite
(N
, New_Copy_Tree
(Node
(Dcon
)));
7544 Analyze_And_Resolve
(N
);
7545 Set_Is_Static_Expression
(N
, False);
7551 Next_Discriminant
(Disc
);
7552 end loop Discr_Loop
;
7554 -- Note: the above loop should always find a matching
7555 -- discriminant, but if it does not, we just missed an
7556 -- optimization due to some glitch (perhaps a previous error),
7562 -- The only remaining processing is in the case of a discriminant of
7563 -- a concurrent object, where we rewrite the prefix to denote the
7564 -- corresponding record type. If the type is derived and has renamed
7565 -- discriminants, use corresponding discriminant, which is the one
7566 -- that appears in the corresponding record.
7568 if not Is_Concurrent_Type
(Ptyp
) then
7572 Disc
:= Entity
(Selector_Name
(N
));
7574 if Is_Derived_Type
(Ptyp
)
7575 and then Present
(Corresponding_Discriminant
(Disc
))
7577 Disc
:= Corresponding_Discriminant
(Disc
);
7581 Make_Selected_Component
(Loc
,
7583 Unchecked_Convert_To
(Corresponding_Record_Type
(Ptyp
),
7585 Selector_Name
=> Make_Identifier
(Loc
, Chars
(Disc
)));
7590 end Expand_N_Selected_Component
;
7592 --------------------
7593 -- Expand_N_Slice --
7594 --------------------
7596 procedure Expand_N_Slice
(N
: Node_Id
) is
7597 Loc
: constant Source_Ptr
:= Sloc
(N
);
7598 Typ
: constant Entity_Id
:= Etype
(N
);
7599 Pfx
: constant Node_Id
:= Prefix
(N
);
7600 Ptp
: Entity_Id
:= Etype
(Pfx
);
7602 function Is_Procedure_Actual
(N
: Node_Id
) return Boolean;
7603 -- Check whether the argument is an actual for a procedure call, in
7604 -- which case the expansion of a bit-packed slice is deferred until the
7605 -- call itself is expanded. The reason this is required is that we might
7606 -- have an IN OUT or OUT parameter, and the copy out is essential, and
7607 -- that copy out would be missed if we created a temporary here in
7608 -- Expand_N_Slice. Note that we don't bother to test specifically for an
7609 -- IN OUT or OUT mode parameter, since it is a bit tricky to do, and it
7610 -- is harmless to defer expansion in the IN case, since the call
7611 -- processing will still generate the appropriate copy in operation,
7612 -- which will take care of the slice.
7614 procedure Make_Temporary_For_Slice
;
7615 -- Create a named variable for the value of the slice, in cases where
7616 -- the back-end cannot handle it properly, e.g. when packed types or
7617 -- unaligned slices are involved.
7619 -------------------------
7620 -- Is_Procedure_Actual --
7621 -------------------------
7623 function Is_Procedure_Actual
(N
: Node_Id
) return Boolean is
7624 Par
: Node_Id
:= Parent
(N
);
7628 -- If our parent is a procedure call we can return
7630 if Nkind
(Par
) = N_Procedure_Call_Statement
then
7633 -- If our parent is a type conversion, keep climbing the tree,
7634 -- since a type conversion can be a procedure actual. Also keep
7635 -- climbing if parameter association or a qualified expression,
7636 -- since these are additional cases that do can appear on
7637 -- procedure actuals.
7639 elsif Nkind_In
(Par
, N_Type_Conversion
,
7640 N_Parameter_Association
,
7641 N_Qualified_Expression
)
7643 Par
:= Parent
(Par
);
7645 -- Any other case is not what we are looking for
7651 end Is_Procedure_Actual
;
7653 ------------------------------
7654 -- Make_Temporary_For_Slice --
7655 ------------------------------
7657 procedure Make_Temporary_For_Slice
is
7659 Ent
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T', N
);
7663 Make_Object_Declaration
(Loc
,
7664 Defining_Identifier
=> Ent
,
7665 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
));
7667 Set_No_Initialization
(Decl
);
7669 Insert_Actions
(N
, New_List
(
7671 Make_Assignment_Statement
(Loc
,
7672 Name
=> New_Occurrence_Of
(Ent
, Loc
),
7673 Expression
=> Relocate_Node
(N
))));
7675 Rewrite
(N
, New_Occurrence_Of
(Ent
, Loc
));
7676 Analyze_And_Resolve
(N
, Typ
);
7677 end Make_Temporary_For_Slice
;
7679 -- Start of processing for Expand_N_Slice
7682 -- Special handling for access types
7684 if Is_Access_Type
(Ptp
) then
7686 Ptp
:= Designated_Type
(Ptp
);
7689 Make_Explicit_Dereference
(Sloc
(N
),
7690 Prefix
=> Relocate_Node
(Pfx
)));
7692 Analyze_And_Resolve
(Pfx
, Ptp
);
7695 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
7696 -- function, then additional actuals must be passed.
7698 if Ada_Version
>= Ada_05
7699 and then Is_Build_In_Place_Function_Call
(Pfx
)
7701 Make_Build_In_Place_Call_In_Anonymous_Context
(Pfx
);
7704 -- The remaining case to be handled is packed slices. We can leave
7705 -- packed slices as they are in the following situations:
7707 -- 1. Right or left side of an assignment (we can handle this
7708 -- situation correctly in the assignment statement expansion).
7710 -- 2. Prefix of indexed component (the slide is optimized away in this
7711 -- case, see the start of Expand_N_Slice.)
7713 -- 3. Object renaming declaration, since we want the name of the
7714 -- slice, not the value.
7716 -- 4. Argument to procedure call, since copy-in/copy-out handling may
7717 -- be required, and this is handled in the expansion of call
7720 -- 5. Prefix of an address attribute (this is an error which is caught
7721 -- elsewhere, and the expansion would interfere with generating the
7724 if not Is_Packed
(Typ
) then
7726 -- Apply transformation for actuals of a function call, where
7727 -- Expand_Actuals is not used.
7729 if Nkind
(Parent
(N
)) = N_Function_Call
7730 and then Is_Possibly_Unaligned_Slice
(N
)
7732 Make_Temporary_For_Slice
;
7735 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
7736 or else (Nkind
(Parent
(Parent
(N
))) = N_Assignment_Statement
7737 and then Parent
(N
) = Name
(Parent
(Parent
(N
))))
7741 elsif Nkind
(Parent
(N
)) = N_Indexed_Component
7742 or else Is_Renamed_Object
(N
)
7743 or else Is_Procedure_Actual
(N
)
7747 elsif Nkind
(Parent
(N
)) = N_Attribute_Reference
7748 and then Attribute_Name
(Parent
(N
)) = Name_Address
7753 Make_Temporary_For_Slice
;
7757 ------------------------------
7758 -- Expand_N_Type_Conversion --
7759 ------------------------------
7761 procedure Expand_N_Type_Conversion
(N
: Node_Id
) is
7762 Loc
: constant Source_Ptr
:= Sloc
(N
);
7763 Operand
: constant Node_Id
:= Expression
(N
);
7764 Target_Type
: constant Entity_Id
:= Etype
(N
);
7765 Operand_Type
: Entity_Id
:= Etype
(Operand
);
7767 procedure Handle_Changed_Representation
;
7768 -- This is called in the case of record and array type conversions to
7769 -- see if there is a change of representation to be handled. Change of
7770 -- representation is actually handled at the assignment statement level,
7771 -- and what this procedure does is rewrite node N conversion as an
7772 -- assignment to temporary. If there is no change of representation,
7773 -- then the conversion node is unchanged.
7775 procedure Raise_Accessibility_Error
;
7776 -- Called when we know that an accessibility check will fail. Rewrites
7777 -- node N to an appropriate raise statement and outputs warning msgs.
7778 -- The Etype of the raise node is set to Target_Type.
7780 procedure Real_Range_Check
;
7781 -- Handles generation of range check for real target value
7783 -----------------------------------
7784 -- Handle_Changed_Representation --
7785 -----------------------------------
7787 procedure Handle_Changed_Representation
is
7796 -- Nothing else to do if no change of representation
7798 if Same_Representation
(Operand_Type
, Target_Type
) then
7801 -- The real change of representation work is done by the assignment
7802 -- statement processing. So if this type conversion is appearing as
7803 -- the expression of an assignment statement, nothing needs to be
7804 -- done to the conversion.
7806 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
then
7809 -- Otherwise we need to generate a temporary variable, and do the
7810 -- change of representation assignment into that temporary variable.
7811 -- The conversion is then replaced by a reference to this variable.
7816 -- If type is unconstrained we have to add a constraint, copied
7817 -- from the actual value of the left hand side.
7819 if not Is_Constrained
(Target_Type
) then
7820 if Has_Discriminants
(Operand_Type
) then
7821 Disc
:= First_Discriminant
(Operand_Type
);
7823 if Disc
/= First_Stored_Discriminant
(Operand_Type
) then
7824 Disc
:= First_Stored_Discriminant
(Operand_Type
);
7828 while Present
(Disc
) loop
7830 Make_Selected_Component
(Loc
,
7831 Prefix
=> Duplicate_Subexpr_Move_Checks
(Operand
),
7833 Make_Identifier
(Loc
, Chars
(Disc
))));
7834 Next_Discriminant
(Disc
);
7837 elsif Is_Array_Type
(Operand_Type
) then
7838 N_Ix
:= First_Index
(Target_Type
);
7841 for J
in 1 .. Number_Dimensions
(Operand_Type
) loop
7843 -- We convert the bounds explicitly. We use an unchecked
7844 -- conversion because bounds checks are done elsewhere.
7849 Unchecked_Convert_To
(Etype
(N_Ix
),
7850 Make_Attribute_Reference
(Loc
,
7852 Duplicate_Subexpr_No_Checks
7853 (Operand
, Name_Req
=> True),
7854 Attribute_Name
=> Name_First
,
7855 Expressions
=> New_List
(
7856 Make_Integer_Literal
(Loc
, J
)))),
7859 Unchecked_Convert_To
(Etype
(N_Ix
),
7860 Make_Attribute_Reference
(Loc
,
7862 Duplicate_Subexpr_No_Checks
7863 (Operand
, Name_Req
=> True),
7864 Attribute_Name
=> Name_Last
,
7865 Expressions
=> New_List
(
7866 Make_Integer_Literal
(Loc
, J
))))));
7873 Odef
:= New_Occurrence_Of
(Target_Type
, Loc
);
7875 if Present
(Cons
) then
7877 Make_Subtype_Indication
(Loc
,
7878 Subtype_Mark
=> Odef
,
7880 Make_Index_Or_Discriminant_Constraint
(Loc
,
7881 Constraints
=> Cons
));
7884 Temp
:= Make_Temporary
(Loc
, 'C');
7886 Make_Object_Declaration
(Loc
,
7887 Defining_Identifier
=> Temp
,
7888 Object_Definition
=> Odef
);
7890 Set_No_Initialization
(Decl
, True);
7892 -- Insert required actions. It is essential to suppress checks
7893 -- since we have suppressed default initialization, which means
7894 -- that the variable we create may have no discriminants.
7899 Make_Assignment_Statement
(Loc
,
7900 Name
=> New_Occurrence_Of
(Temp
, Loc
),
7901 Expression
=> Relocate_Node
(N
))),
7902 Suppress
=> All_Checks
);
7904 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
7907 end Handle_Changed_Representation
;
7909 -------------------------------
7910 -- Raise_Accessibility_Error --
7911 -------------------------------
7913 procedure Raise_Accessibility_Error
is
7916 Make_Raise_Program_Error
(Sloc
(N
),
7917 Reason
=> PE_Accessibility_Check_Failed
));
7918 Set_Etype
(N
, Target_Type
);
7920 Error_Msg_N
("?accessibility check failure", N
);
7922 ("\?& will be raised at run time", N
, Standard_Program_Error
);
7923 end Raise_Accessibility_Error
;
7925 ----------------------
7926 -- Real_Range_Check --
7927 ----------------------
7929 -- Case of conversions to floating-point or fixed-point. If range checks
7930 -- are enabled and the target type has a range constraint, we convert:
7936 -- Tnn : typ'Base := typ'Base (x);
7937 -- [constraint_error when Tnn < typ'First or else Tnn > typ'Last]
7940 -- This is necessary when there is a conversion of integer to float or
7941 -- to fixed-point to ensure that the correct checks are made. It is not
7942 -- necessary for float to float where it is enough to simply set the
7943 -- Do_Range_Check flag.
7945 procedure Real_Range_Check
is
7946 Btyp
: constant Entity_Id
:= Base_Type
(Target_Type
);
7947 Lo
: constant Node_Id
:= Type_Low_Bound
(Target_Type
);
7948 Hi
: constant Node_Id
:= Type_High_Bound
(Target_Type
);
7949 Xtyp
: constant Entity_Id
:= Etype
(Operand
);
7954 -- Nothing to do if conversion was rewritten
7956 if Nkind
(N
) /= N_Type_Conversion
then
7960 -- Nothing to do if range checks suppressed, or target has the same
7961 -- range as the base type (or is the base type).
7963 if Range_Checks_Suppressed
(Target_Type
)
7964 or else (Lo
= Type_Low_Bound
(Btyp
)
7966 Hi
= Type_High_Bound
(Btyp
))
7971 -- Nothing to do if expression is an entity on which checks have been
7974 if Is_Entity_Name
(Operand
)
7975 and then Range_Checks_Suppressed
(Entity
(Operand
))
7980 -- Nothing to do if bounds are all static and we can tell that the
7981 -- expression is within the bounds of the target. Note that if the
7982 -- operand is of an unconstrained floating-point type, then we do
7983 -- not trust it to be in range (might be infinite)
7986 S_Lo
: constant Node_Id
:= Type_Low_Bound
(Xtyp
);
7987 S_Hi
: constant Node_Id
:= Type_High_Bound
(Xtyp
);
7990 if (not Is_Floating_Point_Type
(Xtyp
)
7991 or else Is_Constrained
(Xtyp
))
7992 and then Compile_Time_Known_Value
(S_Lo
)
7993 and then Compile_Time_Known_Value
(S_Hi
)
7994 and then Compile_Time_Known_Value
(Hi
)
7995 and then Compile_Time_Known_Value
(Lo
)
7998 D_Lov
: constant Ureal
:= Expr_Value_R
(Lo
);
7999 D_Hiv
: constant Ureal
:= Expr_Value_R
(Hi
);
8004 if Is_Real_Type
(Xtyp
) then
8005 S_Lov
:= Expr_Value_R
(S_Lo
);
8006 S_Hiv
:= Expr_Value_R
(S_Hi
);
8008 S_Lov
:= UR_From_Uint
(Expr_Value
(S_Lo
));
8009 S_Hiv
:= UR_From_Uint
(Expr_Value
(S_Hi
));
8013 and then S_Lov
>= D_Lov
8014 and then S_Hiv
<= D_Hiv
8016 Set_Do_Range_Check
(Operand
, False);
8023 -- For float to float conversions, we are done
8025 if Is_Floating_Point_Type
(Xtyp
)
8027 Is_Floating_Point_Type
(Btyp
)
8032 -- Otherwise rewrite the conversion as described above
8034 Conv
:= Relocate_Node
(N
);
8035 Rewrite
(Subtype_Mark
(Conv
), New_Occurrence_Of
(Btyp
, Loc
));
8036 Set_Etype
(Conv
, Btyp
);
8038 -- Enable overflow except for case of integer to float conversions,
8039 -- where it is never required, since we can never have overflow in
8042 if not Is_Integer_Type
(Etype
(Operand
)) then
8043 Enable_Overflow_Check
(Conv
);
8046 Tnn
:= Make_Temporary
(Loc
, 'T', Conv
);
8048 Insert_Actions
(N
, New_List
(
8049 Make_Object_Declaration
(Loc
,
8050 Defining_Identifier
=> Tnn
,
8051 Object_Definition
=> New_Occurrence_Of
(Btyp
, Loc
),
8052 Expression
=> Conv
),
8054 Make_Raise_Constraint_Error
(Loc
,
8059 Left_Opnd
=> New_Occurrence_Of
(Tnn
, Loc
),
8061 Make_Attribute_Reference
(Loc
,
8062 Attribute_Name
=> Name_First
,
8064 New_Occurrence_Of
(Target_Type
, Loc
))),
8068 Left_Opnd
=> New_Occurrence_Of
(Tnn
, Loc
),
8070 Make_Attribute_Reference
(Loc
,
8071 Attribute_Name
=> Name_Last
,
8073 New_Occurrence_Of
(Target_Type
, Loc
)))),
8074 Reason
=> CE_Range_Check_Failed
)));
8076 Rewrite
(N
, New_Occurrence_Of
(Tnn
, Loc
));
8077 Analyze_And_Resolve
(N
, Btyp
);
8078 end Real_Range_Check
;
8080 -- Start of processing for Expand_N_Type_Conversion
8083 -- Nothing at all to do if conversion is to the identical type so remove
8084 -- the conversion completely, it is useless, except that it may carry
8085 -- an Assignment_OK attribute, which must be propagated to the operand.
8087 if Operand_Type
= Target_Type
then
8088 if Assignment_OK
(N
) then
8089 Set_Assignment_OK
(Operand
);
8092 Rewrite
(N
, Relocate_Node
(Operand
));
8096 -- Nothing to do if this is the second argument of read. This is a
8097 -- "backwards" conversion that will be handled by the specialized code
8098 -- in attribute processing.
8100 if Nkind
(Parent
(N
)) = N_Attribute_Reference
8101 and then Attribute_Name
(Parent
(N
)) = Name_Read
8102 and then Next
(First
(Expressions
(Parent
(N
)))) = N
8107 -- Here if we may need to expand conversion
8109 -- If the operand of the type conversion is an arithmetic operation on
8110 -- signed integers, and the based type of the signed integer type in
8111 -- question is smaller than Standard.Integer, we promote both of the
8112 -- operands to type Integer.
8114 -- For example, if we have
8116 -- target-type (opnd1 + opnd2)
8118 -- and opnd1 and opnd2 are of type short integer, then we rewrite
8121 -- target-type (integer(opnd1) + integer(opnd2))
8123 -- We do this because we are always allowed to compute in a larger type
8124 -- if we do the right thing with the result, and in this case we are
8125 -- going to do a conversion which will do an appropriate check to make
8126 -- sure that things are in range of the target type in any case. This
8127 -- avoids some unnecessary intermediate overflows.
8129 -- We might consider a similar transformation in the case where the
8130 -- target is a real type or a 64-bit integer type, and the operand
8131 -- is an arithmetic operation using a 32-bit integer type. However,
8132 -- we do not bother with this case, because it could cause significant
8133 -- ineffiencies on 32-bit machines. On a 64-bit machine it would be
8134 -- much cheaper, but we don't want different behavior on 32-bit and
8135 -- 64-bit machines. Note that the exclusion of the 64-bit case also
8136 -- handles the configurable run-time cases where 64-bit arithmetic
8137 -- may simply be unavailable.
8139 -- Note: this circuit is partially redundant with respect to the circuit
8140 -- in Checks.Apply_Arithmetic_Overflow_Check, but we catch more cases in
8141 -- the processing here. Also we still need the Checks circuit, since we
8142 -- have to be sure not to generate junk overflow checks in the first
8143 -- place, since it would be trick to remove them here!
8145 if Integer_Promotion_Possible
(N
) then
8147 -- All conditions met, go ahead with transformation
8155 Make_Type_Conversion
(Loc
,
8156 Subtype_Mark
=> New_Reference_To
(Standard_Integer
, Loc
),
8157 Expression
=> Relocate_Node
(Right_Opnd
(Operand
)));
8159 Opnd
:= New_Op_Node
(Nkind
(Operand
), Loc
);
8160 Set_Right_Opnd
(Opnd
, R
);
8162 if Nkind
(Operand
) in N_Binary_Op
then
8164 Make_Type_Conversion
(Loc
,
8165 Subtype_Mark
=> New_Reference_To
(Standard_Integer
, Loc
),
8166 Expression
=> Relocate_Node
(Left_Opnd
(Operand
)));
8168 Set_Left_Opnd
(Opnd
, L
);
8172 Make_Type_Conversion
(Loc
,
8173 Subtype_Mark
=> Relocate_Node
(Subtype_Mark
(N
)),
8174 Expression
=> Opnd
));
8176 Analyze_And_Resolve
(N
, Target_Type
);
8181 -- Do validity check if validity checking operands
8183 if Validity_Checks_On
8184 and then Validity_Check_Operands
8186 Ensure_Valid
(Operand
);
8189 -- Special case of converting from non-standard boolean type
8191 if Is_Boolean_Type
(Operand_Type
)
8192 and then (Nonzero_Is_True
(Operand_Type
))
8194 Adjust_Condition
(Operand
);
8195 Set_Etype
(Operand
, Standard_Boolean
);
8196 Operand_Type
:= Standard_Boolean
;
8199 -- Case of converting to an access type
8201 if Is_Access_Type
(Target_Type
) then
8203 -- Apply an accessibility check when the conversion operand is an
8204 -- access parameter (or a renaming thereof), unless conversion was
8205 -- expanded from an Unchecked_ or Unrestricted_Access attribute.
8206 -- Note that other checks may still need to be applied below (such
8207 -- as tagged type checks).
8209 if Is_Entity_Name
(Operand
)
8211 (Is_Formal
(Entity
(Operand
))
8213 (Present
(Renamed_Object
(Entity
(Operand
)))
8214 and then Is_Entity_Name
(Renamed_Object
(Entity
(Operand
)))
8216 (Entity
(Renamed_Object
(Entity
(Operand
))))))
8217 and then Ekind
(Etype
(Operand
)) = E_Anonymous_Access_Type
8218 and then (Nkind
(Original_Node
(N
)) /= N_Attribute_Reference
8219 or else Attribute_Name
(Original_Node
(N
)) = Name_Access
)
8221 Apply_Accessibility_Check
8222 (Operand
, Target_Type
, Insert_Node
=> Operand
);
8224 -- If the level of the operand type is statically deeper than the
8225 -- level of the target type, then force Program_Error. Note that this
8226 -- can only occur for cases where the attribute is within the body of
8227 -- an instantiation (otherwise the conversion will already have been
8228 -- rejected as illegal). Note: warnings are issued by the analyzer
8229 -- for the instance cases.
8231 elsif In_Instance_Body
8232 and then Type_Access_Level
(Operand_Type
) >
8233 Type_Access_Level
(Target_Type
)
8235 Raise_Accessibility_Error
;
8237 -- When the operand is a selected access discriminant the check needs
8238 -- to be made against the level of the object denoted by the prefix
8239 -- of the selected name. Force Program_Error for this case as well
8240 -- (this accessibility violation can only happen if within the body
8241 -- of an instantiation).
8243 elsif In_Instance_Body
8244 and then Ekind
(Operand_Type
) = E_Anonymous_Access_Type
8245 and then Nkind
(Operand
) = N_Selected_Component
8246 and then Object_Access_Level
(Operand
) >
8247 Type_Access_Level
(Target_Type
)
8249 Raise_Accessibility_Error
;
8254 -- Case of conversions of tagged types and access to tagged types
8256 -- When needed, that is to say when the expression is class-wide, Add
8257 -- runtime a tag check for (strict) downward conversion by using the
8258 -- membership test, generating:
8260 -- [constraint_error when Operand not in Target_Type'Class]
8262 -- or in the access type case
8264 -- [constraint_error
8265 -- when Operand /= null
8266 -- and then Operand.all not in
8267 -- Designated_Type (Target_Type)'Class]
8269 if (Is_Access_Type
(Target_Type
)
8270 and then Is_Tagged_Type
(Designated_Type
(Target_Type
)))
8271 or else Is_Tagged_Type
(Target_Type
)
8273 -- Do not do any expansion in the access type case if the parent is a
8274 -- renaming, since this is an error situation which will be caught by
8275 -- Sem_Ch8, and the expansion can interfere with this error check.
8277 if Is_Access_Type
(Target_Type
) and then Is_Renamed_Object
(N
) then
8281 -- Otherwise, proceed with processing tagged conversion
8283 Tagged_Conversion
: declare
8284 Actual_Op_Typ
: Entity_Id
;
8285 Actual_Targ_Typ
: Entity_Id
;
8286 Make_Conversion
: Boolean := False;
8287 Root_Op_Typ
: Entity_Id
;
8289 procedure Make_Tag_Check
(Targ_Typ
: Entity_Id
);
8290 -- Create a membership check to test whether Operand is a member
8291 -- of Targ_Typ. If the original Target_Type is an access, include
8292 -- a test for null value. The check is inserted at N.
8294 --------------------
8295 -- Make_Tag_Check --
8296 --------------------
8298 procedure Make_Tag_Check
(Targ_Typ
: Entity_Id
) is
8303 -- [Constraint_Error
8304 -- when Operand /= null
8305 -- and then Operand.all not in Targ_Typ]
8307 if Is_Access_Type
(Target_Type
) then
8312 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Operand
),
8313 Right_Opnd
=> Make_Null
(Loc
)),
8318 Make_Explicit_Dereference
(Loc
,
8319 Prefix
=> Duplicate_Subexpr_No_Checks
(Operand
)),
8320 Right_Opnd
=> New_Reference_To
(Targ_Typ
, Loc
)));
8323 -- [Constraint_Error when Operand not in Targ_Typ]
8328 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Operand
),
8329 Right_Opnd
=> New_Reference_To
(Targ_Typ
, Loc
));
8333 Make_Raise_Constraint_Error
(Loc
,
8335 Reason
=> CE_Tag_Check_Failed
));
8338 -- Start of processing for Tagged_Conversion
8341 if Is_Access_Type
(Target_Type
) then
8343 -- Handle entities from the limited view
8346 Available_View
(Designated_Type
(Operand_Type
));
8348 Available_View
(Designated_Type
(Target_Type
));
8350 Actual_Op_Typ
:= Operand_Type
;
8351 Actual_Targ_Typ
:= Target_Type
;
8354 Root_Op_Typ
:= Root_Type
(Actual_Op_Typ
);
8356 -- Ada 2005 (AI-251): Handle interface type conversion
8358 if Is_Interface
(Actual_Op_Typ
) then
8359 Expand_Interface_Conversion
(N
, Is_Static
=> False);
8363 if not Tag_Checks_Suppressed
(Actual_Targ_Typ
) then
8365 -- Create a runtime tag check for a downward class-wide type
8368 if Is_Class_Wide_Type
(Actual_Op_Typ
)
8369 and then Actual_Op_Typ
/= Actual_Targ_Typ
8370 and then Root_Op_Typ
/= Actual_Targ_Typ
8371 and then Is_Ancestor
(Root_Op_Typ
, Actual_Targ_Typ
)
8373 Make_Tag_Check
(Class_Wide_Type
(Actual_Targ_Typ
));
8374 Make_Conversion
:= True;
8377 -- AI05-0073: If the result subtype of the function is defined
8378 -- by an access_definition designating a specific tagged type
8379 -- T, a check is made that the result value is null or the tag
8380 -- of the object designated by the result value identifies T.
8381 -- Constraint_Error is raised if this check fails.
8383 if Nkind
(Parent
(N
)) = Sinfo
.N_Return_Statement
then
8386 Func_Typ
: Entity_Id
;
8389 -- Climb scope stack looking for the enclosing function
8391 Func
:= Current_Scope
;
8392 while Present
(Func
)
8393 and then Ekind
(Func
) /= E_Function
8395 Func
:= Scope
(Func
);
8398 -- The function's return subtype must be defined using
8399 -- an access definition.
8401 if Nkind
(Result_Definition
(Parent
(Func
))) =
8404 Func_Typ
:= Directly_Designated_Type
(Etype
(Func
));
8406 -- The return subtype denotes a specific tagged type,
8407 -- in other words, a non class-wide type.
8409 if Is_Tagged_Type
(Func_Typ
)
8410 and then not Is_Class_Wide_Type
(Func_Typ
)
8412 Make_Tag_Check
(Actual_Targ_Typ
);
8413 Make_Conversion
:= True;
8419 -- We have generated a tag check for either a class-wide type
8420 -- conversion or for AI05-0073.
8422 if Make_Conversion
then
8427 Make_Unchecked_Type_Conversion
(Loc
,
8428 Subtype_Mark
=> New_Occurrence_Of
(Target_Type
, Loc
),
8429 Expression
=> Relocate_Node
(Expression
(N
)));
8431 Analyze_And_Resolve
(N
, Target_Type
);
8435 end Tagged_Conversion
;
8437 -- Case of other access type conversions
8439 elsif Is_Access_Type
(Target_Type
) then
8440 Apply_Constraint_Check
(Operand
, Target_Type
);
8442 -- Case of conversions from a fixed-point type
8444 -- These conversions require special expansion and processing, found in
8445 -- the Exp_Fixd package. We ignore cases where Conversion_OK is set,
8446 -- since from a semantic point of view, these are simple integer
8447 -- conversions, which do not need further processing.
8449 elsif Is_Fixed_Point_Type
(Operand_Type
)
8450 and then not Conversion_OK
(N
)
8452 -- We should never see universal fixed at this case, since the
8453 -- expansion of the constituent divide or multiply should have
8454 -- eliminated the explicit mention of universal fixed.
8456 pragma Assert
(Operand_Type
/= Universal_Fixed
);
8458 -- Check for special case of the conversion to universal real that
8459 -- occurs as a result of the use of a round attribute. In this case,
8460 -- the real type for the conversion is taken from the target type of
8461 -- the Round attribute and the result must be marked as rounded.
8463 if Target_Type
= Universal_Real
8464 and then Nkind
(Parent
(N
)) = N_Attribute_Reference
8465 and then Attribute_Name
(Parent
(N
)) = Name_Round
8467 Set_Rounded_Result
(N
);
8468 Set_Etype
(N
, Etype
(Parent
(N
)));
8471 -- Otherwise do correct fixed-conversion, but skip these if the
8472 -- Conversion_OK flag is set, because from a semantic point of view
8473 -- these are simple integer conversions needing no further processing
8474 -- (the backend will simply treat them as integers).
8476 if not Conversion_OK
(N
) then
8477 if Is_Fixed_Point_Type
(Etype
(N
)) then
8478 Expand_Convert_Fixed_To_Fixed
(N
);
8481 elsif Is_Integer_Type
(Etype
(N
)) then
8482 Expand_Convert_Fixed_To_Integer
(N
);
8485 pragma Assert
(Is_Floating_Point_Type
(Etype
(N
)));
8486 Expand_Convert_Fixed_To_Float
(N
);
8491 -- Case of conversions to a fixed-point type
8493 -- These conversions require special expansion and processing, found in
8494 -- the Exp_Fixd package. Again, ignore cases where Conversion_OK is set,
8495 -- since from a semantic point of view, these are simple integer
8496 -- conversions, which do not need further processing.
8498 elsif Is_Fixed_Point_Type
(Target_Type
)
8499 and then not Conversion_OK
(N
)
8501 if Is_Integer_Type
(Operand_Type
) then
8502 Expand_Convert_Integer_To_Fixed
(N
);
8505 pragma Assert
(Is_Floating_Point_Type
(Operand_Type
));
8506 Expand_Convert_Float_To_Fixed
(N
);
8510 -- Case of float-to-integer conversions
8512 -- We also handle float-to-fixed conversions with Conversion_OK set
8513 -- since semantically the fixed-point target is treated as though it
8514 -- were an integer in such cases.
8516 elsif Is_Floating_Point_Type
(Operand_Type
)
8518 (Is_Integer_Type
(Target_Type
)
8520 (Is_Fixed_Point_Type
(Target_Type
) and then Conversion_OK
(N
)))
8522 -- One more check here, gcc is still not able to do conversions of
8523 -- this type with proper overflow checking, and so gigi is doing an
8524 -- approximation of what is required by doing floating-point compares
8525 -- with the end-point. But that can lose precision in some cases, and
8526 -- give a wrong result. Converting the operand to Universal_Real is
8527 -- helpful, but still does not catch all cases with 64-bit integers
8528 -- on targets with only 64-bit floats.
8530 -- The above comment seems obsoleted by Apply_Float_Conversion_Check
8531 -- Can this code be removed ???
8533 if Do_Range_Check
(Operand
) then
8535 Make_Type_Conversion
(Loc
,
8537 New_Occurrence_Of
(Universal_Real
, Loc
),
8539 Relocate_Node
(Operand
)));
8541 Set_Etype
(Operand
, Universal_Real
);
8542 Enable_Range_Check
(Operand
);
8543 Set_Do_Range_Check
(Expression
(Operand
), False);
8546 -- Case of array conversions
8548 -- Expansion of array conversions, add required length/range checks but
8549 -- only do this if there is no change of representation. For handling of
8550 -- this case, see Handle_Changed_Representation.
8552 elsif Is_Array_Type
(Target_Type
) then
8554 if Is_Constrained
(Target_Type
) then
8555 Apply_Length_Check
(Operand
, Target_Type
);
8557 Apply_Range_Check
(Operand
, Target_Type
);
8560 Handle_Changed_Representation
;
8562 -- Case of conversions of discriminated types
8564 -- Add required discriminant checks if target is constrained. Again this
8565 -- change is skipped if we have a change of representation.
8567 elsif Has_Discriminants
(Target_Type
)
8568 and then Is_Constrained
(Target_Type
)
8570 Apply_Discriminant_Check
(Operand
, Target_Type
);
8571 Handle_Changed_Representation
;
8573 -- Case of all other record conversions. The only processing required
8574 -- is to check for a change of representation requiring the special
8575 -- assignment processing.
8577 elsif Is_Record_Type
(Target_Type
) then
8579 -- Ada 2005 (AI-216): Program_Error is raised when converting from
8580 -- a derived Unchecked_Union type to an unconstrained type that is
8581 -- not Unchecked_Union if the operand lacks inferable discriminants.
8583 if Is_Derived_Type
(Operand_Type
)
8584 and then Is_Unchecked_Union
(Base_Type
(Operand_Type
))
8585 and then not Is_Constrained
(Target_Type
)
8586 and then not Is_Unchecked_Union
(Base_Type
(Target_Type
))
8587 and then not Has_Inferable_Discriminants
(Operand
)
8589 -- To prevent Gigi from generating illegal code, we generate a
8590 -- Program_Error node, but we give it the target type of the
8594 PE
: constant Node_Id
:= Make_Raise_Program_Error
(Loc
,
8595 Reason
=> PE_Unchecked_Union_Restriction
);
8598 Set_Etype
(PE
, Target_Type
);
8603 Handle_Changed_Representation
;
8606 -- Case of conversions of enumeration types
8608 elsif Is_Enumeration_Type
(Target_Type
) then
8610 -- Special processing is required if there is a change of
8611 -- representation (from enumeration representation clauses).
8613 if not Same_Representation
(Target_Type
, Operand_Type
) then
8615 -- Convert: x(y) to x'val (ytyp'val (y))
8618 Make_Attribute_Reference
(Loc
,
8619 Prefix
=> New_Occurrence_Of
(Target_Type
, Loc
),
8620 Attribute_Name
=> Name_Val
,
8621 Expressions
=> New_List
(
8622 Make_Attribute_Reference
(Loc
,
8623 Prefix
=> New_Occurrence_Of
(Operand_Type
, Loc
),
8624 Attribute_Name
=> Name_Pos
,
8625 Expressions
=> New_List
(Operand
)))));
8627 Analyze_And_Resolve
(N
, Target_Type
);
8630 -- Case of conversions to floating-point
8632 elsif Is_Floating_Point_Type
(Target_Type
) then
8636 -- At this stage, either the conversion node has been transformed into
8637 -- some other equivalent expression, or left as a conversion that can be
8638 -- handled by Gigi, in the following cases:
8640 -- Conversions with no change of representation or type
8642 -- Numeric conversions involving integer, floating- and fixed-point
8643 -- values. Fixed-point values are allowed only if Conversion_OK is
8644 -- set, i.e. if the fixed-point values are to be treated as integers.
8646 -- No other conversions should be passed to Gigi
8648 -- Check: are these rules stated in sinfo??? if so, why restate here???
8650 -- The only remaining step is to generate a range check if we still have
8651 -- a type conversion at this stage and Do_Range_Check is set. For now we
8652 -- do this only for conversions of discrete types.
8654 if Nkind
(N
) = N_Type_Conversion
8655 and then Is_Discrete_Type
(Etype
(N
))
8658 Expr
: constant Node_Id
:= Expression
(N
);
8663 if Do_Range_Check
(Expr
)
8664 and then Is_Discrete_Type
(Etype
(Expr
))
8666 Set_Do_Range_Check
(Expr
, False);
8668 -- Before we do a range check, we have to deal with treating a
8669 -- fixed-point operand as an integer. The way we do this is
8670 -- simply to do an unchecked conversion to an appropriate
8671 -- integer type large enough to hold the result.
8673 -- This code is not active yet, because we are only dealing
8674 -- with discrete types so far ???
8676 if Nkind
(Expr
) in N_Has_Treat_Fixed_As_Integer
8677 and then Treat_Fixed_As_Integer
(Expr
)
8679 Ftyp
:= Base_Type
(Etype
(Expr
));
8681 if Esize
(Ftyp
) >= Esize
(Standard_Integer
) then
8682 Ityp
:= Standard_Long_Long_Integer
;
8684 Ityp
:= Standard_Integer
;
8687 Rewrite
(Expr
, Unchecked_Convert_To
(Ityp
, Expr
));
8690 -- Reset overflow flag, since the range check will include
8691 -- dealing with possible overflow, and generate the check. If
8692 -- Address is either a source type or target type, suppress
8693 -- range check to avoid typing anomalies when it is a visible
8696 Set_Do_Overflow_Check
(N
, False);
8697 if not Is_Descendent_Of_Address
(Etype
(Expr
))
8698 and then not Is_Descendent_Of_Address
(Target_Type
)
8700 Generate_Range_Check
8701 (Expr
, Target_Type
, CE_Range_Check_Failed
);
8707 -- Final step, if the result is a type conversion involving Vax_Float
8708 -- types, then it is subject for further special processing.
8710 if Nkind
(N
) = N_Type_Conversion
8711 and then (Vax_Float
(Operand_Type
) or else Vax_Float
(Target_Type
))
8713 Expand_Vax_Conversion
(N
);
8716 end Expand_N_Type_Conversion
;
8718 -----------------------------------
8719 -- Expand_N_Unchecked_Expression --
8720 -----------------------------------
8722 -- Remove the unchecked expression node from the tree. Its job was simply
8723 -- to make sure that its constituent expression was handled with checks
8724 -- off, and now that that is done, we can remove it from the tree, and
8725 -- indeed must, since Gigi does not expect to see these nodes.
8727 procedure Expand_N_Unchecked_Expression
(N
: Node_Id
) is
8728 Exp
: constant Node_Id
:= Expression
(N
);
8730 Set_Assignment_OK
(Exp
, Assignment_OK
(N
) or else Assignment_OK
(Exp
));
8732 end Expand_N_Unchecked_Expression
;
8734 ----------------------------------------
8735 -- Expand_N_Unchecked_Type_Conversion --
8736 ----------------------------------------
8738 -- If this cannot be handled by Gigi and we haven't already made a
8739 -- temporary for it, do it now.
8741 procedure Expand_N_Unchecked_Type_Conversion
(N
: Node_Id
) is
8742 Target_Type
: constant Entity_Id
:= Etype
(N
);
8743 Operand
: constant Node_Id
:= Expression
(N
);
8744 Operand_Type
: constant Entity_Id
:= Etype
(Operand
);
8747 -- Nothing at all to do if conversion is to the identical type so remove
8748 -- the conversion completely, it is useless, except that it may carry
8749 -- an Assignment_OK indication which must be propagated to the operand.
8751 if Operand_Type
= Target_Type
then
8753 -- Code duplicates Expand_N_Unchecked_Expression above, factor???
8755 if Assignment_OK
(N
) then
8756 Set_Assignment_OK
(Operand
);
8759 Rewrite
(N
, Relocate_Node
(Operand
));
8763 -- If we have a conversion of a compile time known value to a target
8764 -- type and the value is in range of the target type, then we can simply
8765 -- replace the construct by an integer literal of the correct type. We
8766 -- only apply this to integer types being converted. Possibly it may
8767 -- apply in other cases, but it is too much trouble to worry about.
8769 -- Note that we do not do this transformation if the Kill_Range_Check
8770 -- flag is set, since then the value may be outside the expected range.
8771 -- This happens in the Normalize_Scalars case.
8773 -- We also skip this if either the target or operand type is biased
8774 -- because in this case, the unchecked conversion is supposed to
8775 -- preserve the bit pattern, not the integer value.
8777 if Is_Integer_Type
(Target_Type
)
8778 and then not Has_Biased_Representation
(Target_Type
)
8779 and then Is_Integer_Type
(Operand_Type
)
8780 and then not Has_Biased_Representation
(Operand_Type
)
8781 and then Compile_Time_Known_Value
(Operand
)
8782 and then not Kill_Range_Check
(N
)
8785 Val
: constant Uint
:= Expr_Value
(Operand
);
8788 if Compile_Time_Known_Value
(Type_Low_Bound
(Target_Type
))
8790 Compile_Time_Known_Value
(Type_High_Bound
(Target_Type
))
8792 Val
>= Expr_Value
(Type_Low_Bound
(Target_Type
))
8794 Val
<= Expr_Value
(Type_High_Bound
(Target_Type
))
8796 Rewrite
(N
, Make_Integer_Literal
(Sloc
(N
), Val
));
8798 -- If Address is the target type, just set the type to avoid a
8799 -- spurious type error on the literal when Address is a visible
8802 if Is_Descendent_Of_Address
(Target_Type
) then
8803 Set_Etype
(N
, Target_Type
);
8805 Analyze_And_Resolve
(N
, Target_Type
);
8813 -- Nothing to do if conversion is safe
8815 if Safe_Unchecked_Type_Conversion
(N
) then
8819 -- Otherwise force evaluation unless Assignment_OK flag is set (this
8820 -- flag indicates ??? -- more comments needed here)
8822 if Assignment_OK
(N
) then
8825 Force_Evaluation
(N
);
8827 end Expand_N_Unchecked_Type_Conversion
;
8829 ----------------------------
8830 -- Expand_Record_Equality --
8831 ----------------------------
8833 -- For non-variant records, Equality is expanded when needed into:
8835 -- and then Lhs.Discr1 = Rhs.Discr1
8837 -- and then Lhs.Discrn = Rhs.Discrn
8838 -- and then Lhs.Cmp1 = Rhs.Cmp1
8840 -- and then Lhs.Cmpn = Rhs.Cmpn
8842 -- The expression is folded by the back-end for adjacent fields. This
8843 -- function is called for tagged record in only one occasion: for imple-
8844 -- menting predefined primitive equality (see Predefined_Primitives_Bodies)
8845 -- otherwise the primitive "=" is used directly.
8847 function Expand_Record_Equality
8852 Bodies
: List_Id
) return Node_Id
8854 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
8859 First_Time
: Boolean := True;
8861 function Suitable_Element
(C
: Entity_Id
) return Entity_Id
;
8862 -- Return the first field to compare beginning with C, skipping the
8863 -- inherited components.
8865 ----------------------
8866 -- Suitable_Element --
8867 ----------------------
8869 function Suitable_Element
(C
: Entity_Id
) return Entity_Id
is
8874 elsif Ekind
(C
) /= E_Discriminant
8875 and then Ekind
(C
) /= E_Component
8877 return Suitable_Element
(Next_Entity
(C
));
8879 elsif Is_Tagged_Type
(Typ
)
8880 and then C
/= Original_Record_Component
(C
)
8882 return Suitable_Element
(Next_Entity
(C
));
8884 elsif Chars
(C
) = Name_uController
8885 or else Chars
(C
) = Name_uTag
8887 return Suitable_Element
(Next_Entity
(C
));
8889 elsif Is_Interface
(Etype
(C
)) then
8890 return Suitable_Element
(Next_Entity
(C
));
8895 end Suitable_Element
;
8897 -- Start of processing for Expand_Record_Equality
8900 -- Generates the following code: (assuming that Typ has one Discr and
8901 -- component C2 is also a record)
8904 -- and then Lhs.Discr1 = Rhs.Discr1
8905 -- and then Lhs.C1 = Rhs.C1
8906 -- and then Lhs.C2.C1=Rhs.C2.C1 and then ... Lhs.C2.Cn=Rhs.C2.Cn
8908 -- and then Lhs.Cmpn = Rhs.Cmpn
8910 Result
:= New_Reference_To
(Standard_True
, Loc
);
8911 C
:= Suitable_Element
(First_Entity
(Typ
));
8912 while Present
(C
) loop
8920 First_Time
:= False;
8924 New_Lhs
:= New_Copy_Tree
(Lhs
);
8925 New_Rhs
:= New_Copy_Tree
(Rhs
);
8929 Expand_Composite_Equality
(Nod
, Etype
(C
),
8931 Make_Selected_Component
(Loc
,
8933 Selector_Name
=> New_Reference_To
(C
, Loc
)),
8935 Make_Selected_Component
(Loc
,
8937 Selector_Name
=> New_Reference_To
(C
, Loc
)),
8940 -- If some (sub)component is an unchecked_union, the whole
8941 -- operation will raise program error.
8943 if Nkind
(Check
) = N_Raise_Program_Error
then
8945 Set_Etype
(Result
, Standard_Boolean
);
8950 Left_Opnd
=> Result
,
8951 Right_Opnd
=> Check
);
8955 C
:= Suitable_Element
(Next_Entity
(C
));
8959 end Expand_Record_Equality
;
8961 -----------------------------------
8962 -- Expand_Short_Circuit_Operator --
8963 -----------------------------------
8965 -- Deal with special expansion if actions are present for the right operand
8966 -- and deal with optimizing case of arguments being True or False. We also
8967 -- deal with the special case of non-standard boolean values.
8969 procedure Expand_Short_Circuit_Operator
(N
: Node_Id
) is
8970 Loc
: constant Source_Ptr
:= Sloc
(N
);
8971 Typ
: constant Entity_Id
:= Etype
(N
);
8972 Left
: constant Node_Id
:= Left_Opnd
(N
);
8973 Right
: constant Node_Id
:= Right_Opnd
(N
);
8974 LocR
: constant Source_Ptr
:= Sloc
(Right
);
8977 Shortcut_Value
: constant Boolean := Nkind
(N
) = N_Or_Else
;
8978 Shortcut_Ent
: constant Entity_Id
:= Boolean_Literals
(Shortcut_Value
);
8979 -- If Left = Shortcut_Value then Right need not be evaluated
8981 function Make_Test_Expr
(Opnd
: Node_Id
) return Node_Id
;
8982 -- For Opnd a boolean expression, return a Boolean expression equivalent
8983 -- to Opnd /= Shortcut_Value.
8985 --------------------
8986 -- Make_Test_Expr --
8987 --------------------
8989 function Make_Test_Expr
(Opnd
: Node_Id
) return Node_Id
is
8991 if Shortcut_Value
then
8992 return Make_Op_Not
(Sloc
(Opnd
), Opnd
);
8999 -- Entity for a temporary variable holding the value of the operator,
9000 -- used for expansion in the case where actions are present.
9002 -- Start of processing for Expand_Short_Circuit_Operator
9005 -- Deal with non-standard booleans
9007 if Is_Boolean_Type
(Typ
) then
9008 Adjust_Condition
(Left
);
9009 Adjust_Condition
(Right
);
9010 Set_Etype
(N
, Standard_Boolean
);
9013 -- Check for cases where left argument is known to be True or False
9015 if Compile_Time_Known_Value
(Left
) then
9017 -- Mark SCO for left condition as compile time known
9019 if Generate_SCO
and then Comes_From_Source
(Left
) then
9020 Set_SCO_Condition
(Left
, Expr_Value_E
(Left
) = Standard_True
);
9023 -- Rewrite True AND THEN Right / False OR ELSE Right to Right.
9024 -- Any actions associated with Right will be executed unconditionally
9025 -- and can thus be inserted into the tree unconditionally.
9027 if Expr_Value_E
(Left
) /= Shortcut_Ent
then
9028 if Present
(Actions
(N
)) then
9029 Insert_Actions
(N
, Actions
(N
));
9034 -- Rewrite False AND THEN Right / True OR ELSE Right to Left.
9035 -- In this case we can forget the actions associated with Right,
9036 -- since they will never be executed.
9039 Kill_Dead_Code
(Right
);
9040 Kill_Dead_Code
(Actions
(N
));
9041 Rewrite
(N
, New_Occurrence_Of
(Shortcut_Ent
, Loc
));
9044 Adjust_Result_Type
(N
, Typ
);
9048 -- If Actions are present for the right operand, we have to do some
9049 -- special processing. We can't just let these actions filter back into
9050 -- code preceding the short circuit (which is what would have happened
9051 -- if we had not trapped them in the short-circuit form), since they
9052 -- must only be executed if the right operand of the short circuit is
9053 -- executed and not otherwise.
9055 -- the temporary variable C.
9057 if Present
(Actions
(N
)) then
9058 Actlist
:= Actions
(N
);
9060 -- The old approach is to expand:
9062 -- left AND THEN right
9066 -- C : Boolean := False;
9074 -- and finally rewrite the operator into a reference to C. Similarly
9075 -- for left OR ELSE right, with negated values. Note that this
9076 -- rewrite causes some difficulties for coverage analysis because
9077 -- of the introduction of the new variable C, which obscures the
9078 -- structure of the test.
9080 -- We use this "old approach" if use of N_Expression_With_Actions
9081 -- is False (see description in Opt of when this is or is not set).
9083 if not Use_Expression_With_Actions
then
9084 Op_Var
:= Make_Temporary
(Loc
, 'C', Related_Node
=> N
);
9087 Make_Object_Declaration
(Loc
,
9088 Defining_Identifier
=>
9090 Object_Definition
=>
9091 New_Occurrence_Of
(Standard_Boolean
, Loc
),
9093 New_Occurrence_Of
(Shortcut_Ent
, Loc
)));
9096 Make_Implicit_If_Statement
(Right
,
9097 Condition
=> Make_Test_Expr
(Right
),
9098 Then_Statements
=> New_List
(
9099 Make_Assignment_Statement
(LocR
,
9100 Name
=> New_Occurrence_Of
(Op_Var
, LocR
),
9103 (Boolean_Literals
(not Shortcut_Value
), LocR
)))));
9106 Make_Implicit_If_Statement
(Left
,
9107 Condition
=> Make_Test_Expr
(Left
),
9108 Then_Statements
=> Actlist
));
9110 Rewrite
(N
, New_Occurrence_Of
(Op_Var
, Loc
));
9111 Analyze_And_Resolve
(N
, Standard_Boolean
);
9113 -- The new approach, activated for now by the use of debug flag
9114 -- -gnatd.X is to use the new Expression_With_Actions node for the
9115 -- right operand of the short-circuit form. This should solve the
9116 -- traceability problems for coverage analysis.
9120 Make_Expression_With_Actions
(LocR
,
9121 Expression
=> Relocate_Node
(Right
),
9122 Actions
=> Actlist
));
9123 Set_Actions
(N
, No_List
);
9124 Analyze_And_Resolve
(Right
, Standard_Boolean
);
9127 Adjust_Result_Type
(N
, Typ
);
9131 -- No actions present, check for cases of right argument True/False
9133 if Compile_Time_Known_Value
(Right
) then
9135 -- Mark SCO for left condition as compile time known
9137 if Generate_SCO
and then Comes_From_Source
(Right
) then
9138 Set_SCO_Condition
(Right
, Expr_Value_E
(Right
) = Standard_True
);
9141 -- Change (Left and then True), (Left or else False) to Left.
9142 -- Note that we know there are no actions associated with the right
9143 -- operand, since we just checked for this case above.
9145 if Expr_Value_E
(Right
) /= Shortcut_Ent
then
9148 -- Change (Left and then False), (Left or else True) to Right,
9149 -- making sure to preserve any side effects associated with the Left
9153 Remove_Side_Effects
(Left
);
9154 Rewrite
(N
, New_Occurrence_Of
(Shortcut_Ent
, Loc
));
9158 Adjust_Result_Type
(N
, Typ
);
9159 end Expand_Short_Circuit_Operator
;
9161 -------------------------------------
9162 -- Fixup_Universal_Fixed_Operation --
9163 -------------------------------------
9165 procedure Fixup_Universal_Fixed_Operation
(N
: Node_Id
) is
9166 Conv
: constant Node_Id
:= Parent
(N
);
9169 -- We must have a type conversion immediately above us
9171 pragma Assert
(Nkind
(Conv
) = N_Type_Conversion
);
9173 -- Normally the type conversion gives our target type. The exception
9174 -- occurs in the case of the Round attribute, where the conversion
9175 -- will be to universal real, and our real type comes from the Round
9176 -- attribute (as well as an indication that we must round the result)
9178 if Nkind
(Parent
(Conv
)) = N_Attribute_Reference
9179 and then Attribute_Name
(Parent
(Conv
)) = Name_Round
9181 Set_Etype
(N
, Etype
(Parent
(Conv
)));
9182 Set_Rounded_Result
(N
);
9184 -- Normal case where type comes from conversion above us
9187 Set_Etype
(N
, Etype
(Conv
));
9189 end Fixup_Universal_Fixed_Operation
;
9191 ------------------------------
9192 -- Get_Allocator_Final_List --
9193 ------------------------------
9195 function Get_Allocator_Final_List
9198 PtrT
: Entity_Id
) return Entity_Id
9200 Loc
: constant Source_Ptr
:= Sloc
(N
);
9202 Owner
: Entity_Id
:= PtrT
;
9203 -- The entity whose finalization list must be used to attach the
9204 -- allocated object.
9207 if Ekind
(PtrT
) = E_Anonymous_Access_Type
then
9209 -- If the context is an access parameter, we need to create a
9210 -- non-anonymous access type in order to have a usable final list,
9211 -- because there is otherwise no pool to which the allocated object
9212 -- can belong. We create both the type and the finalization chain
9213 -- here, because freezing an internal type does not create such a
9214 -- chain. The Final_Chain that is thus created is shared by the
9215 -- access parameter. The access type is tested against the result
9216 -- type of the function to exclude allocators whose type is an
9217 -- anonymous access result type. We freeze the type at once to
9218 -- ensure that it is properly decorated for the back-end, even
9219 -- if the context and current scope is a loop.
9221 if Nkind
(Associated_Node_For_Itype
(PtrT
))
9222 in N_Subprogram_Specification
9225 Etype
(Defining_Unit_Name
(Associated_Node_For_Itype
(PtrT
)))
9227 Owner
:= Make_Temporary
(Loc
, 'J');
9229 Make_Full_Type_Declaration
(Loc
,
9230 Defining_Identifier
=> Owner
,
9232 Make_Access_To_Object_Definition
(Loc
,
9233 Subtype_Indication
=>
9234 New_Occurrence_Of
(T
, Loc
))));
9236 Freeze_Before
(N
, Owner
);
9237 Build_Final_List
(N
, Owner
);
9238 Set_Associated_Final_Chain
(PtrT
, Associated_Final_Chain
(Owner
));
9240 -- Ada 2005 (AI-318-02): If the context is a return object
9241 -- declaration, then the anonymous return subtype is defined to have
9242 -- the same accessibility level as that of the function's result
9243 -- subtype, which means that we want the scope where the function is
9246 elsif Nkind
(Associated_Node_For_Itype
(PtrT
)) = N_Object_Declaration
9247 and then Ekind
(Scope
(PtrT
)) = E_Return_Statement
9249 Owner
:= Scope
(Return_Applies_To
(Scope
(PtrT
)));
9251 -- Case of an access discriminant, or (Ada 2005) of an anonymous
9252 -- access component or anonymous access function result: find the
9253 -- final list associated with the scope of the type. (In the
9254 -- anonymous access component kind, a list controller will have
9255 -- been allocated when freezing the record type, and PtrT has an
9256 -- Associated_Final_Chain attribute designating it.)
9258 elsif No
(Associated_Final_Chain
(PtrT
)) then
9259 Owner
:= Scope
(PtrT
);
9263 return Find_Final_List
(Owner
);
9264 end Get_Allocator_Final_List
;
9266 ---------------------------------
9267 -- Has_Inferable_Discriminants --
9268 ---------------------------------
9270 function Has_Inferable_Discriminants
(N
: Node_Id
) return Boolean is
9272 function Prefix_Is_Formal_Parameter
(N
: Node_Id
) return Boolean;
9273 -- Determines whether the left-most prefix of a selected component is a
9274 -- formal parameter in a subprogram. Assumes N is a selected component.
9276 --------------------------------
9277 -- Prefix_Is_Formal_Parameter --
9278 --------------------------------
9280 function Prefix_Is_Formal_Parameter
(N
: Node_Id
) return Boolean is
9281 Sel_Comp
: Node_Id
:= N
;
9284 -- Move to the left-most prefix by climbing up the tree
9286 while Present
(Parent
(Sel_Comp
))
9287 and then Nkind
(Parent
(Sel_Comp
)) = N_Selected_Component
9289 Sel_Comp
:= Parent
(Sel_Comp
);
9292 return Ekind
(Entity
(Prefix
(Sel_Comp
))) in Formal_Kind
;
9293 end Prefix_Is_Formal_Parameter
;
9295 -- Start of processing for Has_Inferable_Discriminants
9298 -- For identifiers and indexed components, it is sufficient to have a
9299 -- constrained Unchecked_Union nominal subtype.
9301 if Nkind_In
(N
, N_Identifier
, N_Indexed_Component
) then
9302 return Is_Unchecked_Union
(Base_Type
(Etype
(N
)))
9304 Is_Constrained
(Etype
(N
));
9306 -- For selected components, the subtype of the selector must be a
9307 -- constrained Unchecked_Union. If the component is subject to a
9308 -- per-object constraint, then the enclosing object must have inferable
9311 elsif Nkind
(N
) = N_Selected_Component
then
9312 if Has_Per_Object_Constraint
(Entity
(Selector_Name
(N
))) then
9314 -- A small hack. If we have a per-object constrained selected
9315 -- component of a formal parameter, return True since we do not
9316 -- know the actual parameter association yet.
9318 if Prefix_Is_Formal_Parameter
(N
) then
9322 -- Otherwise, check the enclosing object and the selector
9324 return Has_Inferable_Discriminants
(Prefix
(N
))
9326 Has_Inferable_Discriminants
(Selector_Name
(N
));
9329 -- The call to Has_Inferable_Discriminants will determine whether
9330 -- the selector has a constrained Unchecked_Union nominal type.
9332 return Has_Inferable_Discriminants
(Selector_Name
(N
));
9334 -- A qualified expression has inferable discriminants if its subtype
9335 -- mark is a constrained Unchecked_Union subtype.
9337 elsif Nkind
(N
) = N_Qualified_Expression
then
9338 return Is_Unchecked_Union
(Subtype_Mark
(N
))
9340 Is_Constrained
(Subtype_Mark
(N
));
9345 end Has_Inferable_Discriminants
;
9347 -------------------------------
9348 -- Insert_Dereference_Action --
9349 -------------------------------
9351 procedure Insert_Dereference_Action
(N
: Node_Id
) is
9352 Loc
: constant Source_Ptr
:= Sloc
(N
);
9353 Typ
: constant Entity_Id
:= Etype
(N
);
9354 Pool
: constant Entity_Id
:= Associated_Storage_Pool
(Typ
);
9355 Pnod
: constant Node_Id
:= Parent
(N
);
9357 function Is_Checked_Storage_Pool
(P
: Entity_Id
) return Boolean;
9358 -- Return true if type of P is derived from Checked_Pool;
9360 -----------------------------
9361 -- Is_Checked_Storage_Pool --
9362 -----------------------------
9364 function Is_Checked_Storage_Pool
(P
: Entity_Id
) return Boolean is
9373 while T
/= Etype
(T
) loop
9374 if Is_RTE
(T
, RE_Checked_Pool
) then
9382 end Is_Checked_Storage_Pool
;
9384 -- Start of processing for Insert_Dereference_Action
9387 pragma Assert
(Nkind
(Pnod
) = N_Explicit_Dereference
);
9389 if not (Is_Checked_Storage_Pool
(Pool
)
9390 and then Comes_From_Source
(Original_Node
(Pnod
)))
9396 Make_Procedure_Call_Statement
(Loc
,
9397 Name
=> New_Reference_To
(
9398 Find_Prim_Op
(Etype
(Pool
), Name_Dereference
), Loc
),
9400 Parameter_Associations
=> New_List
(
9404 New_Reference_To
(Pool
, Loc
),
9406 -- Storage_Address. We use the attribute Pool_Address, which uses
9407 -- the pointer itself to find the address of the object, and which
9408 -- handles unconstrained arrays properly by computing the address
9409 -- of the template. i.e. the correct address of the corresponding
9412 Make_Attribute_Reference
(Loc
,
9413 Prefix
=> Duplicate_Subexpr_Move_Checks
(N
),
9414 Attribute_Name
=> Name_Pool_Address
),
9416 -- Size_In_Storage_Elements
9418 Make_Op_Divide
(Loc
,
9420 Make_Attribute_Reference
(Loc
,
9422 Make_Explicit_Dereference
(Loc
,
9423 Duplicate_Subexpr_Move_Checks
(N
)),
9424 Attribute_Name
=> Name_Size
),
9426 Make_Integer_Literal
(Loc
, System_Storage_Unit
)),
9430 Make_Attribute_Reference
(Loc
,
9432 Make_Explicit_Dereference
(Loc
,
9433 Duplicate_Subexpr_Move_Checks
(N
)),
9434 Attribute_Name
=> Name_Alignment
))));
9437 when RE_Not_Available
=>
9439 end Insert_Dereference_Action
;
9441 --------------------------------
9442 -- Integer_Promotion_Possible --
9443 --------------------------------
9445 function Integer_Promotion_Possible
(N
: Node_Id
) return Boolean is
9446 Operand
: constant Node_Id
:= Expression
(N
);
9447 Operand_Type
: constant Entity_Id
:= Etype
(Operand
);
9448 Root_Operand_Type
: constant Entity_Id
:= Root_Type
(Operand_Type
);
9451 pragma Assert
(Nkind
(N
) = N_Type_Conversion
);
9455 -- We only do the transformation for source constructs. We assume
9456 -- that the expander knows what it is doing when it generates code.
9458 Comes_From_Source
(N
)
9460 -- If the operand type is Short_Integer or Short_Short_Integer,
9461 -- then we will promote to Integer, which is available on all
9462 -- targets, and is sufficient to ensure no intermediate overflow.
9463 -- Furthermore it is likely to be as efficient or more efficient
9464 -- than using the smaller type for the computation so we do this
9468 (Root_Operand_Type
= Base_Type
(Standard_Short_Integer
)
9470 Root_Operand_Type
= Base_Type
(Standard_Short_Short_Integer
))
9472 -- Test for interesting operation, which includes addition,
9473 -- division, exponentiation, multiplication, subtraction, absolute
9474 -- value and unary negation. Unary "+" is omitted since it is a
9475 -- no-op and thus can't overflow.
9477 and then Nkind_In
(Operand
, N_Op_Abs
,
9484 end Integer_Promotion_Possible
;
9486 ------------------------------
9487 -- Make_Array_Comparison_Op --
9488 ------------------------------
9490 -- This is a hand-coded expansion of the following generic function:
9493 -- type elem is (<>);
9494 -- type index is (<>);
9495 -- type a is array (index range <>) of elem;
9497 -- function Gnnn (X : a; Y: a) return boolean is
9498 -- J : index := Y'first;
9501 -- if X'length = 0 then
9504 -- elsif Y'length = 0 then
9508 -- for I in X'range loop
9509 -- if X (I) = Y (J) then
9510 -- if J = Y'last then
9513 -- J := index'succ (J);
9517 -- return X (I) > Y (J);
9521 -- return X'length > Y'length;
9525 -- Note that since we are essentially doing this expansion by hand, we
9526 -- do not need to generate an actual or formal generic part, just the
9527 -- instantiated function itself.
9529 function Make_Array_Comparison_Op
9531 Nod
: Node_Id
) return Node_Id
9533 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
9535 X
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uX
);
9536 Y
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uY
);
9537 I
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uI
);
9538 J
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uJ
);
9540 Index
: constant Entity_Id
:= Base_Type
(Etype
(First_Index
(Typ
)));
9542 Loop_Statement
: Node_Id
;
9543 Loop_Body
: Node_Id
;
9546 Final_Expr
: Node_Id
;
9547 Func_Body
: Node_Id
;
9548 Func_Name
: Entity_Id
;
9554 -- if J = Y'last then
9557 -- J := index'succ (J);
9561 Make_Implicit_If_Statement
(Nod
,
9564 Left_Opnd
=> New_Reference_To
(J
, Loc
),
9566 Make_Attribute_Reference
(Loc
,
9567 Prefix
=> New_Reference_To
(Y
, Loc
),
9568 Attribute_Name
=> Name_Last
)),
9570 Then_Statements
=> New_List
(
9571 Make_Exit_Statement
(Loc
)),
9575 Make_Assignment_Statement
(Loc
,
9576 Name
=> New_Reference_To
(J
, Loc
),
9578 Make_Attribute_Reference
(Loc
,
9579 Prefix
=> New_Reference_To
(Index
, Loc
),
9580 Attribute_Name
=> Name_Succ
,
9581 Expressions
=> New_List
(New_Reference_To
(J
, Loc
))))));
9583 -- if X (I) = Y (J) then
9586 -- return X (I) > Y (J);
9590 Make_Implicit_If_Statement
(Nod
,
9594 Make_Indexed_Component
(Loc
,
9595 Prefix
=> New_Reference_To
(X
, Loc
),
9596 Expressions
=> New_List
(New_Reference_To
(I
, Loc
))),
9599 Make_Indexed_Component
(Loc
,
9600 Prefix
=> New_Reference_To
(Y
, Loc
),
9601 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)))),
9603 Then_Statements
=> New_List
(Inner_If
),
9605 Else_Statements
=> New_List
(
9606 Make_Simple_Return_Statement
(Loc
,
9610 Make_Indexed_Component
(Loc
,
9611 Prefix
=> New_Reference_To
(X
, Loc
),
9612 Expressions
=> New_List
(New_Reference_To
(I
, Loc
))),
9615 Make_Indexed_Component
(Loc
,
9616 Prefix
=> New_Reference_To
(Y
, Loc
),
9617 Expressions
=> New_List
(
9618 New_Reference_To
(J
, Loc
)))))));
9620 -- for I in X'range loop
9625 Make_Implicit_Loop_Statement
(Nod
,
9626 Identifier
=> Empty
,
9629 Make_Iteration_Scheme
(Loc
,
9630 Loop_Parameter_Specification
=>
9631 Make_Loop_Parameter_Specification
(Loc
,
9632 Defining_Identifier
=> I
,
9633 Discrete_Subtype_Definition
=>
9634 Make_Attribute_Reference
(Loc
,
9635 Prefix
=> New_Reference_To
(X
, Loc
),
9636 Attribute_Name
=> Name_Range
))),
9638 Statements
=> New_List
(Loop_Body
));
9640 -- if X'length = 0 then
9642 -- elsif Y'length = 0 then
9645 -- for ... loop ... end loop;
9646 -- return X'length > Y'length;
9650 Make_Attribute_Reference
(Loc
,
9651 Prefix
=> New_Reference_To
(X
, Loc
),
9652 Attribute_Name
=> Name_Length
);
9655 Make_Attribute_Reference
(Loc
,
9656 Prefix
=> New_Reference_To
(Y
, Loc
),
9657 Attribute_Name
=> Name_Length
);
9661 Left_Opnd
=> Length1
,
9662 Right_Opnd
=> Length2
);
9665 Make_Implicit_If_Statement
(Nod
,
9669 Make_Attribute_Reference
(Loc
,
9670 Prefix
=> New_Reference_To
(X
, Loc
),
9671 Attribute_Name
=> Name_Length
),
9673 Make_Integer_Literal
(Loc
, 0)),
9677 Make_Simple_Return_Statement
(Loc
,
9678 Expression
=> New_Reference_To
(Standard_False
, Loc
))),
9680 Elsif_Parts
=> New_List
(
9681 Make_Elsif_Part
(Loc
,
9685 Make_Attribute_Reference
(Loc
,
9686 Prefix
=> New_Reference_To
(Y
, Loc
),
9687 Attribute_Name
=> Name_Length
),
9689 Make_Integer_Literal
(Loc
, 0)),
9693 Make_Simple_Return_Statement
(Loc
,
9694 Expression
=> New_Reference_To
(Standard_True
, Loc
))))),
9696 Else_Statements
=> New_List
(
9698 Make_Simple_Return_Statement
(Loc
,
9699 Expression
=> Final_Expr
)));
9703 Formals
:= New_List
(
9704 Make_Parameter_Specification
(Loc
,
9705 Defining_Identifier
=> X
,
9706 Parameter_Type
=> New_Reference_To
(Typ
, Loc
)),
9708 Make_Parameter_Specification
(Loc
,
9709 Defining_Identifier
=> Y
,
9710 Parameter_Type
=> New_Reference_To
(Typ
, Loc
)));
9712 -- function Gnnn (...) return boolean is
9713 -- J : index := Y'first;
9718 Func_Name
:= Make_Temporary
(Loc
, 'G');
9721 Make_Subprogram_Body
(Loc
,
9723 Make_Function_Specification
(Loc
,
9724 Defining_Unit_Name
=> Func_Name
,
9725 Parameter_Specifications
=> Formals
,
9726 Result_Definition
=> New_Reference_To
(Standard_Boolean
, Loc
)),
9728 Declarations
=> New_List
(
9729 Make_Object_Declaration
(Loc
,
9730 Defining_Identifier
=> J
,
9731 Object_Definition
=> New_Reference_To
(Index
, Loc
),
9733 Make_Attribute_Reference
(Loc
,
9734 Prefix
=> New_Reference_To
(Y
, Loc
),
9735 Attribute_Name
=> Name_First
))),
9737 Handled_Statement_Sequence
=>
9738 Make_Handled_Sequence_Of_Statements
(Loc
,
9739 Statements
=> New_List
(If_Stat
)));
9742 end Make_Array_Comparison_Op
;
9744 ---------------------------
9745 -- Make_Boolean_Array_Op --
9746 ---------------------------
9748 -- For logical operations on boolean arrays, expand in line the following,
9749 -- replacing 'and' with 'or' or 'xor' where needed:
9751 -- function Annn (A : typ; B: typ) return typ is
9754 -- for J in A'range loop
9755 -- C (J) := A (J) op B (J);
9760 -- Here typ is the boolean array type
9762 function Make_Boolean_Array_Op
9764 N
: Node_Id
) return Node_Id
9766 Loc
: constant Source_Ptr
:= Sloc
(N
);
9768 A
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uA
);
9769 B
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uB
);
9770 C
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uC
);
9771 J
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uJ
);
9779 Func_Name
: Entity_Id
;
9780 Func_Body
: Node_Id
;
9781 Loop_Statement
: Node_Id
;
9785 Make_Indexed_Component
(Loc
,
9786 Prefix
=> New_Reference_To
(A
, Loc
),
9787 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)));
9790 Make_Indexed_Component
(Loc
,
9791 Prefix
=> New_Reference_To
(B
, Loc
),
9792 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)));
9795 Make_Indexed_Component
(Loc
,
9796 Prefix
=> New_Reference_To
(C
, Loc
),
9797 Expressions
=> New_List
(New_Reference_To
(J
, Loc
)));
9799 if Nkind
(N
) = N_Op_And
then
9805 elsif Nkind
(N
) = N_Op_Or
then
9819 Make_Implicit_Loop_Statement
(N
,
9820 Identifier
=> Empty
,
9823 Make_Iteration_Scheme
(Loc
,
9824 Loop_Parameter_Specification
=>
9825 Make_Loop_Parameter_Specification
(Loc
,
9826 Defining_Identifier
=> J
,
9827 Discrete_Subtype_Definition
=>
9828 Make_Attribute_Reference
(Loc
,
9829 Prefix
=> New_Reference_To
(A
, Loc
),
9830 Attribute_Name
=> Name_Range
))),
9832 Statements
=> New_List
(
9833 Make_Assignment_Statement
(Loc
,
9835 Expression
=> Op
)));
9837 Formals
:= New_List
(
9838 Make_Parameter_Specification
(Loc
,
9839 Defining_Identifier
=> A
,
9840 Parameter_Type
=> New_Reference_To
(Typ
, Loc
)),
9842 Make_Parameter_Specification
(Loc
,
9843 Defining_Identifier
=> B
,
9844 Parameter_Type
=> New_Reference_To
(Typ
, Loc
)));
9846 Func_Name
:= Make_Temporary
(Loc
, 'A');
9847 Set_Is_Inlined
(Func_Name
);
9850 Make_Subprogram_Body
(Loc
,
9852 Make_Function_Specification
(Loc
,
9853 Defining_Unit_Name
=> Func_Name
,
9854 Parameter_Specifications
=> Formals
,
9855 Result_Definition
=> New_Reference_To
(Typ
, Loc
)),
9857 Declarations
=> New_List
(
9858 Make_Object_Declaration
(Loc
,
9859 Defining_Identifier
=> C
,
9860 Object_Definition
=> New_Reference_To
(Typ
, Loc
))),
9862 Handled_Statement_Sequence
=>
9863 Make_Handled_Sequence_Of_Statements
(Loc
,
9864 Statements
=> New_List
(
9866 Make_Simple_Return_Statement
(Loc
,
9867 Expression
=> New_Reference_To
(C
, Loc
)))));
9870 end Make_Boolean_Array_Op
;
9872 ------------------------
9873 -- Rewrite_Comparison --
9874 ------------------------
9876 procedure Rewrite_Comparison
(N
: Node_Id
) is
9877 Warning_Generated
: Boolean := False;
9878 -- Set to True if first pass with Assume_Valid generates a warning in
9879 -- which case we skip the second pass to avoid warning overloaded.
9882 -- Set to Standard_True or Standard_False
9885 if Nkind
(N
) = N_Type_Conversion
then
9886 Rewrite_Comparison
(Expression
(N
));
9889 elsif Nkind
(N
) not in N_Op_Compare
then
9893 -- Now start looking at the comparison in detail. We potentially go
9894 -- through this loop twice. The first time, Assume_Valid is set False
9895 -- in the call to Compile_Time_Compare. If this call results in a
9896 -- clear result of always True or Always False, that's decisive and
9897 -- we are done. Otherwise we repeat the processing with Assume_Valid
9898 -- set to True to generate additional warnings. We can skip that step
9899 -- if Constant_Condition_Warnings is False.
9901 for AV
in False .. True loop
9903 Typ
: constant Entity_Id
:= Etype
(N
);
9904 Op1
: constant Node_Id
:= Left_Opnd
(N
);
9905 Op2
: constant Node_Id
:= Right_Opnd
(N
);
9907 Res
: constant Compare_Result
:=
9908 Compile_Time_Compare
(Op1
, Op2
, Assume_Valid
=> AV
);
9909 -- Res indicates if compare outcome can be compile time determined
9911 True_Result
: Boolean;
9912 False_Result
: Boolean;
9915 case N_Op_Compare
(Nkind
(N
)) is
9917 True_Result
:= Res
= EQ
;
9918 False_Result
:= Res
= LT
or else Res
= GT
or else Res
= NE
;
9921 True_Result
:= Res
in Compare_GE
;
9922 False_Result
:= Res
= LT
;
9925 and then Constant_Condition_Warnings
9926 and then Comes_From_Source
(Original_Node
(N
))
9927 and then Nkind
(Original_Node
(N
)) = N_Op_Ge
9928 and then not In_Instance
9929 and then Is_Integer_Type
(Etype
(Left_Opnd
(N
)))
9930 and then not Has_Warnings_Off
(Etype
(Left_Opnd
(N
)))
9933 ("can never be greater than, could replace by ""'=""?", N
);
9934 Warning_Generated
:= True;
9938 True_Result
:= Res
= GT
;
9939 False_Result
:= Res
in Compare_LE
;
9942 True_Result
:= Res
= LT
;
9943 False_Result
:= Res
in Compare_GE
;
9946 True_Result
:= Res
in Compare_LE
;
9947 False_Result
:= Res
= GT
;
9950 and then Constant_Condition_Warnings
9951 and then Comes_From_Source
(Original_Node
(N
))
9952 and then Nkind
(Original_Node
(N
)) = N_Op_Le
9953 and then not In_Instance
9954 and then Is_Integer_Type
(Etype
(Left_Opnd
(N
)))
9955 and then not Has_Warnings_Off
(Etype
(Left_Opnd
(N
)))
9958 ("can never be less than, could replace by ""'=""?", N
);
9959 Warning_Generated
:= True;
9963 True_Result
:= Res
= NE
or else Res
= GT
or else Res
= LT
;
9964 False_Result
:= Res
= EQ
;
9967 -- If this is the first iteration, then we actually convert the
9968 -- comparison into True or False, if the result is certain.
9971 if True_Result
or False_Result
then
9973 Result
:= Standard_True
;
9975 Result
:= Standard_False
;
9980 New_Occurrence_Of
(Result
, Sloc
(N
))));
9981 Analyze_And_Resolve
(N
, Typ
);
9982 Warn_On_Known_Condition
(N
);
9986 -- If this is the second iteration (AV = True), and the original
9987 -- node comes from source and we are not in an instance, then give
9988 -- a warning if we know result would be True or False. Note: we
9989 -- know Constant_Condition_Warnings is set if we get here.
9991 elsif Comes_From_Source
(Original_Node
(N
))
9992 and then not In_Instance
9996 ("condition can only be False if invalid values present?",
9998 elsif False_Result
then
10000 ("condition can only be True if invalid values present?",
10006 -- Skip second iteration if not warning on constant conditions or
10007 -- if the first iteration already generated a warning of some kind or
10008 -- if we are in any case assuming all values are valid (so that the
10009 -- first iteration took care of the valid case).
10011 exit when not Constant_Condition_Warnings
;
10012 exit when Warning_Generated
;
10013 exit when Assume_No_Invalid_Values
;
10015 end Rewrite_Comparison
;
10017 ----------------------------
10018 -- Safe_In_Place_Array_Op --
10019 ----------------------------
10021 function Safe_In_Place_Array_Op
10024 Op2
: Node_Id
) return Boolean
10026 Target
: Entity_Id
;
10028 function Is_Safe_Operand
(Op
: Node_Id
) return Boolean;
10029 -- Operand is safe if it cannot overlap part of the target of the
10030 -- operation. If the operand and the target are identical, the operand
10031 -- is safe. The operand can be empty in the case of negation.
10033 function Is_Unaliased
(N
: Node_Id
) return Boolean;
10034 -- Check that N is a stand-alone entity
10040 function Is_Unaliased
(N
: Node_Id
) return Boolean is
10044 and then No
(Address_Clause
(Entity
(N
)))
10045 and then No
(Renamed_Object
(Entity
(N
)));
10048 ---------------------
10049 -- Is_Safe_Operand --
10050 ---------------------
10052 function Is_Safe_Operand
(Op
: Node_Id
) return Boolean is
10057 elsif Is_Entity_Name
(Op
) then
10058 return Is_Unaliased
(Op
);
10060 elsif Nkind_In
(Op
, N_Indexed_Component
, N_Selected_Component
) then
10061 return Is_Unaliased
(Prefix
(Op
));
10063 elsif Nkind
(Op
) = N_Slice
then
10065 Is_Unaliased
(Prefix
(Op
))
10066 and then Entity
(Prefix
(Op
)) /= Target
;
10068 elsif Nkind
(Op
) = N_Op_Not
then
10069 return Is_Safe_Operand
(Right_Opnd
(Op
));
10074 end Is_Safe_Operand
;
10076 -- Start of processing for Is_Safe_In_Place_Array_Op
10079 -- Skip this processing if the component size is different from system
10080 -- storage unit (since at least for NOT this would cause problems).
10082 if Component_Size
(Etype
(Lhs
)) /= System_Storage_Unit
then
10085 -- Cannot do in place stuff on VM_Target since cannot pass addresses
10087 elsif VM_Target
/= No_VM
then
10090 -- Cannot do in place stuff if non-standard Boolean representation
10092 elsif Has_Non_Standard_Rep
(Component_Type
(Etype
(Lhs
))) then
10095 elsif not Is_Unaliased
(Lhs
) then
10099 Target
:= Entity
(Lhs
);
10100 return Is_Safe_Operand
(Op1
) and then Is_Safe_Operand
(Op2
);
10102 end Safe_In_Place_Array_Op
;
10104 -----------------------
10105 -- Tagged_Membership --
10106 -----------------------
10108 -- There are two different cases to consider depending on whether the right
10109 -- operand is a class-wide type or not. If not we just compare the actual
10110 -- tag of the left expr to the target type tag:
10112 -- Left_Expr.Tag = Right_Type'Tag;
10114 -- If it is a class-wide type we use the RT function CW_Membership which is
10115 -- usually implemented by looking in the ancestor tables contained in the
10116 -- dispatch table pointed by Left_Expr.Tag for Typ'Tag
10118 -- Ada 2005 (AI-251): If it is a class-wide interface type we use the RT
10119 -- function IW_Membership which is usually implemented by looking in the
10120 -- table of abstract interface types plus the ancestor table contained in
10121 -- the dispatch table pointed by Left_Expr.Tag for Typ'Tag
10123 procedure Tagged_Membership
10125 SCIL_Node
: out Node_Id
;
10126 Result
: out Node_Id
)
10128 Left
: constant Node_Id
:= Left_Opnd
(N
);
10129 Right
: constant Node_Id
:= Right_Opnd
(N
);
10130 Loc
: constant Source_Ptr
:= Sloc
(N
);
10132 Left_Type
: Entity_Id
;
10133 New_Node
: Node_Id
;
10134 Right_Type
: Entity_Id
;
10138 SCIL_Node
:= Empty
;
10140 -- Handle entities from the limited view
10142 Left_Type
:= Available_View
(Etype
(Left
));
10143 Right_Type
:= Available_View
(Etype
(Right
));
10145 if Is_Class_Wide_Type
(Left_Type
) then
10146 Left_Type
:= Root_Type
(Left_Type
);
10150 Make_Selected_Component
(Loc
,
10151 Prefix
=> Relocate_Node
(Left
),
10153 New_Reference_To
(First_Tag_Component
(Left_Type
), Loc
));
10155 if Is_Class_Wide_Type
(Right_Type
) then
10157 -- No need to issue a run-time check if we statically know that the
10158 -- result of this membership test is always true. For example,
10159 -- considering the following declarations:
10161 -- type Iface is interface;
10162 -- type T is tagged null record;
10163 -- type DT is new T and Iface with null record;
10168 -- These membership tests are always true:
10171 -- Obj2 in T'Class;
10172 -- Obj2 in Iface'Class;
10174 -- We do not need to handle cases where the membership is illegal.
10177 -- Obj1 in DT'Class; -- Compile time error
10178 -- Obj1 in Iface'Class; -- Compile time error
10180 if not Is_Class_Wide_Type
(Left_Type
)
10181 and then (Is_Ancestor
(Etype
(Right_Type
), Left_Type
)
10182 or else (Is_Interface
(Etype
(Right_Type
))
10183 and then Interface_Present_In_Ancestor
10185 Iface
=> Etype
(Right_Type
))))
10187 Result
:= New_Reference_To
(Standard_True
, Loc
);
10191 -- Ada 2005 (AI-251): Class-wide applied to interfaces
10193 if Is_Interface
(Etype
(Class_Wide_Type
(Right_Type
)))
10195 -- Support to: "Iface_CW_Typ in Typ'Class"
10197 or else Is_Interface
(Left_Type
)
10199 -- Issue error if IW_Membership operation not available in a
10200 -- configurable run time setting.
10202 if not RTE_Available
(RE_IW_Membership
) then
10204 ("dynamic membership test on interface types", N
);
10210 Make_Function_Call
(Loc
,
10211 Name
=> New_Occurrence_Of
(RTE
(RE_IW_Membership
), Loc
),
10212 Parameter_Associations
=> New_List
(
10213 Make_Attribute_Reference
(Loc
,
10215 Attribute_Name
=> Name_Address
),
10218 (Access_Disp_Table
(Root_Type
(Right_Type
)))),
10221 -- Ada 95: Normal case
10224 Build_CW_Membership
(Loc
,
10225 Obj_Tag_Node
=> Obj_Tag
,
10229 (Access_Disp_Table
(Root_Type
(Right_Type
)))),
10232 New_Node
=> New_Node
);
10234 -- Generate the SCIL node for this class-wide membership test.
10235 -- Done here because the previous call to Build_CW_Membership
10236 -- relocates Obj_Tag.
10238 if Generate_SCIL
then
10239 SCIL_Node
:= Make_SCIL_Membership_Test
(Sloc
(N
));
10240 Set_SCIL_Entity
(SCIL_Node
, Etype
(Right_Type
));
10241 Set_SCIL_Tag_Value
(SCIL_Node
, Obj_Tag
);
10244 Result
:= New_Node
;
10247 -- Right_Type is not a class-wide type
10250 -- No need to check the tag of the object if Right_Typ is abstract
10252 if Is_Abstract_Type
(Right_Type
) then
10253 Result
:= New_Reference_To
(Standard_False
, Loc
);
10258 Left_Opnd
=> Obj_Tag
,
10261 (Node
(First_Elmt
(Access_Disp_Table
(Right_Type
))), Loc
));
10264 end Tagged_Membership
;
10266 ------------------------------
10267 -- Unary_Op_Validity_Checks --
10268 ------------------------------
10270 procedure Unary_Op_Validity_Checks
(N
: Node_Id
) is
10272 if Validity_Checks_On
and Validity_Check_Operands
then
10273 Ensure_Valid
(Right_Opnd
(N
));
10275 end Unary_Op_Validity_Checks
;