1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, 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_Ch2
; use Exp_Ch2
;
35 with Exp_Ch3
; use Exp_Ch3
;
36 with Exp_Ch6
; use Exp_Ch6
;
37 with Exp_Ch7
; use Exp_Ch7
;
38 with Exp_Ch9
; use Exp_Ch9
;
39 with Exp_Disp
; use Exp_Disp
;
40 with Exp_Fixd
; use Exp_Fixd
;
41 with Exp_Intr
; use Exp_Intr
;
42 with Exp_Pakd
; use Exp_Pakd
;
43 with Exp_Tss
; use Exp_Tss
;
44 with Exp_Util
; use Exp_Util
;
45 with Freeze
; use Freeze
;
46 with Inline
; use Inline
;
48 with Namet
; use Namet
;
49 with Nlists
; use Nlists
;
50 with Nmake
; use Nmake
;
52 with Par_SCO
; use Par_SCO
;
53 with Restrict
; use Restrict
;
54 with Rident
; use Rident
;
55 with Rtsfind
; use Rtsfind
;
57 with Sem_Aux
; use Sem_Aux
;
58 with Sem_Cat
; use Sem_Cat
;
59 with Sem_Ch3
; use Sem_Ch3
;
60 with Sem_Ch8
; use Sem_Ch8
;
61 with Sem_Ch13
; use Sem_Ch13
;
62 with Sem_Eval
; use Sem_Eval
;
63 with Sem_Res
; use Sem_Res
;
64 with Sem_Type
; use Sem_Type
;
65 with Sem_Util
; use Sem_Util
;
66 with Sem_Warn
; use Sem_Warn
;
67 with Sinfo
; use Sinfo
;
68 with Snames
; use Snames
;
69 with Stand
; use Stand
;
70 with SCIL_LL
; use SCIL_LL
;
71 with Targparm
; use Targparm
;
72 with Tbuild
; use Tbuild
;
73 with Ttypes
; use Ttypes
;
74 with Uintp
; use Uintp
;
75 with Urealp
; use Urealp
;
76 with Validsw
; use Validsw
;
78 package body Exp_Ch4
is
80 -----------------------
81 -- Local Subprograms --
82 -----------------------
84 procedure Binary_Op_Validity_Checks
(N
: Node_Id
);
85 pragma Inline
(Binary_Op_Validity_Checks
);
86 -- Performs validity checks for a binary operator
88 procedure Build_Boolean_Array_Proc_Call
92 -- If a boolean array assignment can be done in place, build call to
93 -- corresponding library procedure.
95 function Current_Anonymous_Master
return Entity_Id
;
96 -- Return the entity of the heterogeneous finalization master belonging to
97 -- the current unit (either function, package or procedure). This master
98 -- services all anonymous access-to-controlled types. If the current unit
99 -- does not have such master, create one.
101 procedure Displace_Allocator_Pointer
(N
: Node_Id
);
102 -- Ada 2005 (AI-251): Subsidiary procedure to Expand_N_Allocator and
103 -- Expand_Allocator_Expression. Allocating class-wide interface objects
104 -- this routine displaces the pointer to the allocated object to reference
105 -- the component referencing the corresponding secondary dispatch table.
107 procedure Expand_Allocator_Expression
(N
: Node_Id
);
108 -- Subsidiary to Expand_N_Allocator, for the case when the expression
109 -- is a qualified expression or an aggregate.
111 procedure Expand_Array_Comparison
(N
: Node_Id
);
112 -- This routine handles expansion of the comparison operators (N_Op_Lt,
113 -- N_Op_Le, N_Op_Gt, N_Op_Ge) when operating on an array type. The basic
114 -- code for these operators is similar, differing only in the details of
115 -- the actual comparison call that is made. Special processing (call a
118 function Expand_Array_Equality
123 Typ
: Entity_Id
) return Node_Id
;
124 -- Expand an array equality into a call to a function implementing this
125 -- equality, and a call to it. Loc is the location for the generated nodes.
126 -- Lhs and Rhs are the array expressions to be compared. Bodies is a list
127 -- on which to attach bodies of local functions that are created in the
128 -- process. It is the responsibility of the caller to insert those bodies
129 -- at the right place. Nod provides the Sloc value for the generated code.
130 -- Normally the types used for the generated equality routine are taken
131 -- from Lhs and Rhs. However, in some situations of generated code, the
132 -- Etype fields of Lhs and Rhs are not set yet. In such cases, Typ supplies
133 -- the type to be used for the formal parameters.
135 procedure Expand_Boolean_Operator
(N
: Node_Id
);
136 -- Common expansion processing for Boolean operators (And, Or, Xor) for the
137 -- case of array type arguments.
139 procedure Expand_Short_Circuit_Operator
(N
: Node_Id
);
140 -- Common expansion processing for short-circuit boolean operators
142 procedure Expand_Compare_Minimize_Eliminate_Overflow
(N
: Node_Id
);
143 -- Deal with comparison in MINIMIZED/ELIMINATED overflow mode. This is
144 -- where we allow comparison of "out of range" values.
146 function Expand_Composite_Equality
151 Bodies
: List_Id
) return Node_Id
;
152 -- Local recursive function used to expand equality for nested composite
153 -- types. Used by Expand_Record/Array_Equality, Bodies is a list on which
154 -- to attach bodies of local functions that are created in the process. It
155 -- is the responsibility of the caller to insert those bodies at the right
156 -- place. Nod provides the Sloc value for generated code. Lhs and Rhs are
157 -- the left and right sides for the comparison, and Typ is the type of the
158 -- objects to compare.
160 procedure Expand_Concatenate
(Cnode
: Node_Id
; Opnds
: List_Id
);
161 -- Routine to expand concatenation of a sequence of two or more operands
162 -- (in the list Operands) and replace node Cnode with the result of the
163 -- concatenation. The operands can be of any appropriate type, and can
164 -- include both arrays and singleton elements.
166 procedure Expand_Membership_Minimize_Eliminate_Overflow
(N
: Node_Id
);
167 -- N is an N_In membership test mode, with the overflow check mode set to
168 -- MINIMIZED or ELIMINATED, and the type of the left operand is a signed
169 -- integer type. This is a case where top level processing is required to
170 -- handle overflow checks in subtrees.
172 procedure Fixup_Universal_Fixed_Operation
(N
: Node_Id
);
173 -- N is a N_Op_Divide or N_Op_Multiply node whose result is universal
174 -- fixed. We do not have such a type at runtime, so the purpose of this
175 -- routine is to find the real type by looking up the tree. We also
176 -- determine if the operation must be rounded.
178 function Has_Inferable_Discriminants
(N
: Node_Id
) return Boolean;
179 -- Ada 2005 (AI-216): A view of an Unchecked_Union object has inferable
180 -- discriminants if it has a constrained nominal type, unless the object
181 -- is a component of an enclosing Unchecked_Union object that is subject
182 -- to a per-object constraint and the enclosing object lacks inferable
185 -- An expression of an Unchecked_Union type has inferable discriminants
186 -- if it is either a name of an object with inferable discriminants or a
187 -- qualified expression whose subtype mark denotes a constrained subtype.
189 procedure Insert_Dereference_Action
(N
: Node_Id
);
190 -- N is an expression whose type is an access. When the type of the
191 -- associated storage pool is derived from Checked_Pool, generate a
192 -- call to the 'Dereference' primitive operation.
194 function Make_Array_Comparison_Op
196 Nod
: Node_Id
) return Node_Id
;
197 -- Comparisons between arrays are expanded in line. This function produces
198 -- the body of the implementation of (a > b), where a and b are one-
199 -- dimensional arrays of some discrete type. The original node is then
200 -- expanded into the appropriate call to this function. Nod provides the
201 -- Sloc value for the generated code.
203 function Make_Boolean_Array_Op
205 N
: Node_Id
) return Node_Id
;
206 -- Boolean operations on boolean arrays are expanded in line. This function
207 -- produce the body for the node N, which is (a and b), (a or b), or (a xor
208 -- b). It is used only the normal case and not the packed case. The type
209 -- involved, Typ, is the Boolean array type, and the logical operations in
210 -- the body are simple boolean operations. Note that Typ is always a
211 -- constrained type (the caller has ensured this by using
212 -- Convert_To_Actual_Subtype if necessary).
214 function Minimized_Eliminated_Overflow_Check
(N
: Node_Id
) return Boolean;
215 -- For signed arithmetic operations when the current overflow mode is
216 -- MINIMIZED or ELIMINATED, we must call Apply_Arithmetic_Overflow_Checks
217 -- as the first thing we do. We then return. We count on the recursive
218 -- apparatus for overflow checks to call us back with an equivalent
219 -- operation that is in CHECKED mode, avoiding a recursive entry into this
220 -- routine, and that is when we will proceed with the expansion of the
221 -- operator (e.g. converting X+0 to X, or X**2 to X*X). We cannot do
222 -- these optimizations without first making this check, since there may be
223 -- operands further down the tree that are relying on the recursive calls
224 -- triggered by the top level nodes to properly process overflow checking
225 -- and remaining expansion on these nodes. Note that this call back may be
226 -- skipped if the operation is done in Bignum mode but that's fine, since
227 -- the Bignum call takes care of everything.
229 procedure Optimize_Length_Comparison
(N
: Node_Id
);
230 -- Given an expression, if it is of the form X'Length op N (or the other
231 -- way round), where N is known at compile time to be 0 or 1, and X is a
232 -- simple entity, and op is a comparison operator, optimizes it into a
233 -- comparison of First and Last.
235 procedure Process_Transient_Object
238 -- Subsidiary routine to the expansion of expression_with_actions and if
239 -- expressions. Generate all the necessary code to finalize a transient
240 -- controlled object when the enclosing context is elaborated or evaluated.
241 -- Decl denotes the declaration of the transient controlled object which is
242 -- usually the result of a controlled function call. Rel_Node denotes the
243 -- context, either an expression_with_actions or an if expression.
245 procedure Rewrite_Comparison
(N
: Node_Id
);
246 -- If N is the node for a comparison whose outcome can be determined at
247 -- compile time, then the node N can be rewritten with True or False. If
248 -- the outcome cannot be determined at compile time, the call has no
249 -- effect. If N is a type conversion, then this processing is applied to
250 -- its expression. If N is neither comparison nor a type conversion, the
251 -- call has no effect.
253 procedure Tagged_Membership
255 SCIL_Node
: out Node_Id
;
256 Result
: out Node_Id
);
257 -- Construct the expression corresponding to the tagged membership test.
258 -- Deals with a second operand being (or not) a class-wide type.
260 function Safe_In_Place_Array_Op
263 Op2
: Node_Id
) return Boolean;
264 -- In the context of an assignment, where the right-hand side is a boolean
265 -- operation on arrays, check whether operation can be performed in place.
267 procedure Unary_Op_Validity_Checks
(N
: Node_Id
);
268 pragma Inline
(Unary_Op_Validity_Checks
);
269 -- Performs validity checks for a unary operator
271 -------------------------------
272 -- Binary_Op_Validity_Checks --
273 -------------------------------
275 procedure Binary_Op_Validity_Checks
(N
: Node_Id
) is
277 if Validity_Checks_On
and Validity_Check_Operands
then
278 Ensure_Valid
(Left_Opnd
(N
));
279 Ensure_Valid
(Right_Opnd
(N
));
281 end Binary_Op_Validity_Checks
;
283 ------------------------------------
284 -- Build_Boolean_Array_Proc_Call --
285 ------------------------------------
287 procedure Build_Boolean_Array_Proc_Call
292 Loc
: constant Source_Ptr
:= Sloc
(N
);
293 Kind
: constant Node_Kind
:= Nkind
(Expression
(N
));
294 Target
: constant Node_Id
:=
295 Make_Attribute_Reference
(Loc
,
297 Attribute_Name
=> Name_Address
);
299 Arg1
: Node_Id
:= Op1
;
300 Arg2
: Node_Id
:= Op2
;
302 Proc_Name
: Entity_Id
;
305 if Kind
= N_Op_Not
then
306 if Nkind
(Op1
) in N_Binary_Op
then
308 -- Use negated version of the binary operators
310 if Nkind
(Op1
) = N_Op_And
then
311 Proc_Name
:= RTE
(RE_Vector_Nand
);
313 elsif Nkind
(Op1
) = N_Op_Or
then
314 Proc_Name
:= RTE
(RE_Vector_Nor
);
316 else pragma Assert
(Nkind
(Op1
) = N_Op_Xor
);
317 Proc_Name
:= RTE
(RE_Vector_Xor
);
321 Make_Procedure_Call_Statement
(Loc
,
322 Name
=> New_Occurrence_Of
(Proc_Name
, Loc
),
324 Parameter_Associations
=> New_List
(
326 Make_Attribute_Reference
(Loc
,
327 Prefix
=> Left_Opnd
(Op1
),
328 Attribute_Name
=> Name_Address
),
330 Make_Attribute_Reference
(Loc
,
331 Prefix
=> Right_Opnd
(Op1
),
332 Attribute_Name
=> Name_Address
),
334 Make_Attribute_Reference
(Loc
,
335 Prefix
=> Left_Opnd
(Op1
),
336 Attribute_Name
=> Name_Length
)));
339 Proc_Name
:= RTE
(RE_Vector_Not
);
342 Make_Procedure_Call_Statement
(Loc
,
343 Name
=> New_Occurrence_Of
(Proc_Name
, Loc
),
344 Parameter_Associations
=> New_List
(
347 Make_Attribute_Reference
(Loc
,
349 Attribute_Name
=> Name_Address
),
351 Make_Attribute_Reference
(Loc
,
353 Attribute_Name
=> Name_Length
)));
357 -- We use the following equivalences:
359 -- (not X) or (not Y) = not (X and Y) = Nand (X, Y)
360 -- (not X) and (not Y) = not (X or Y) = Nor (X, Y)
361 -- (not X) xor (not Y) = X xor Y
362 -- X xor (not Y) = not (X xor Y) = Nxor (X, Y)
364 if Nkind
(Op1
) = N_Op_Not
then
365 Arg1
:= Right_Opnd
(Op1
);
366 Arg2
:= Right_Opnd
(Op2
);
368 if Kind
= N_Op_And
then
369 Proc_Name
:= RTE
(RE_Vector_Nor
);
370 elsif Kind
= N_Op_Or
then
371 Proc_Name
:= RTE
(RE_Vector_Nand
);
373 Proc_Name
:= RTE
(RE_Vector_Xor
);
377 if Kind
= N_Op_And
then
378 Proc_Name
:= RTE
(RE_Vector_And
);
379 elsif Kind
= N_Op_Or
then
380 Proc_Name
:= RTE
(RE_Vector_Or
);
381 elsif Nkind
(Op2
) = N_Op_Not
then
382 Proc_Name
:= RTE
(RE_Vector_Nxor
);
383 Arg2
:= Right_Opnd
(Op2
);
385 Proc_Name
:= RTE
(RE_Vector_Xor
);
390 Make_Procedure_Call_Statement
(Loc
,
391 Name
=> New_Occurrence_Of
(Proc_Name
, Loc
),
392 Parameter_Associations
=> New_List
(
394 Make_Attribute_Reference
(Loc
,
396 Attribute_Name
=> Name_Address
),
397 Make_Attribute_Reference
(Loc
,
399 Attribute_Name
=> Name_Address
),
400 Make_Attribute_Reference
(Loc
,
402 Attribute_Name
=> Name_Length
)));
405 Rewrite
(N
, Call_Node
);
409 when RE_Not_Available
=>
411 end Build_Boolean_Array_Proc_Call
;
413 ------------------------------
414 -- Current_Anonymous_Master --
415 ------------------------------
417 function Current_Anonymous_Master
return Entity_Id
is
425 Unit_Id
:= Cunit_Entity
(Current_Sem_Unit
);
427 -- Find the entity of the current unit
429 if Ekind
(Unit_Id
) = E_Subprogram_Body
then
431 -- When processing subprogram bodies, the proper scope is always that
434 Subp_Body
:= Unit_Id
;
435 while Present
(Subp_Body
)
436 and then Nkind
(Subp_Body
) /= N_Subprogram_Body
438 Subp_Body
:= Parent
(Subp_Body
);
441 Unit_Id
:= Corresponding_Spec
(Subp_Body
);
444 Loc
:= Sloc
(Unit_Id
);
445 Unit_Decl
:= Unit
(Cunit
(Current_Sem_Unit
));
447 -- Find the declarations list of the current unit
449 if Nkind
(Unit_Decl
) = N_Package_Declaration
then
450 Unit_Decl
:= Specification
(Unit_Decl
);
451 Decls
:= Visible_Declarations
(Unit_Decl
);
454 Decls
:= New_List
(Make_Null_Statement
(Loc
));
455 Set_Visible_Declarations
(Unit_Decl
, Decls
);
457 elsif Is_Empty_List
(Decls
) then
458 Append_To
(Decls
, Make_Null_Statement
(Loc
));
462 Decls
:= Declarations
(Unit_Decl
);
465 Decls
:= New_List
(Make_Null_Statement
(Loc
));
466 Set_Declarations
(Unit_Decl
, Decls
);
468 elsif Is_Empty_List
(Decls
) then
469 Append_To
(Decls
, Make_Null_Statement
(Loc
));
473 -- The current unit has an existing anonymous master, traverse its
474 -- declarations and locate the entity.
476 if Has_Anonymous_Master
(Unit_Id
) then
479 Fin_Mas_Id
: Entity_Id
;
482 Decl
:= First
(Decls
);
483 while Present
(Decl
) loop
485 -- Look for the first variable in the declarations whole type
486 -- is Finalization_Master.
488 if Nkind
(Decl
) = N_Object_Declaration
then
489 Fin_Mas_Id
:= Defining_Identifier
(Decl
);
491 if Ekind
(Fin_Mas_Id
) = E_Variable
492 and then Etype
(Fin_Mas_Id
) = RTE
(RE_Finalization_Master
)
501 -- The master was not found even though the unit was labeled as
507 -- Create a new anonymous master
511 First_Decl
: constant Node_Id
:= First
(Decls
);
513 Fin_Mas_Id
: Entity_Id
;
516 -- Since the master and its associated initialization is inserted
517 -- at top level, use the scope of the unit when analyzing.
519 Push_Scope
(Unit_Id
);
521 -- Create the finalization master
524 Make_Defining_Identifier
(Loc
,
525 Chars
=> New_External_Name
(Chars
(Unit_Id
), "AM"));
528 -- <Fin_Mas_Id> : Finalization_Master;
531 Make_Object_Declaration
(Loc
,
532 Defining_Identifier
=> Fin_Mas_Id
,
534 New_Occurrence_Of
(RTE
(RE_Finalization_Master
), Loc
));
536 Insert_Before_And_Analyze
(First_Decl
, Action
);
538 -- Mark the unit to prevent the generation of multiple masters
540 Set_Has_Anonymous_Master
(Unit_Id
);
542 -- Do not set the base pool and mode of operation on .NET/JVM
543 -- since those targets do not support pools and all VM masters
544 -- are heterogeneous by default.
546 if VM_Target
= No_VM
then
550 -- (<Fin_Mas_Id>, Global_Pool_Object'Unrestricted_Access);
553 Make_Procedure_Call_Statement
(Loc
,
555 New_Occurrence_Of
(RTE
(RE_Set_Base_Pool
), Loc
),
557 Parameter_Associations
=> New_List
(
558 New_Occurrence_Of
(Fin_Mas_Id
, Loc
),
559 Make_Attribute_Reference
(Loc
,
561 New_Occurrence_Of
(RTE
(RE_Global_Pool_Object
), Loc
),
562 Attribute_Name
=> Name_Unrestricted_Access
)));
564 Insert_Before_And_Analyze
(First_Decl
, Action
);
567 -- Set_Is_Heterogeneous (<Fin_Mas_Id>);
570 Make_Procedure_Call_Statement
(Loc
,
572 New_Occurrence_Of
(RTE
(RE_Set_Is_Heterogeneous
), Loc
),
573 Parameter_Associations
=> New_List
(
574 New_Occurrence_Of
(Fin_Mas_Id
, Loc
)));
576 Insert_Before_And_Analyze
(First_Decl
, Action
);
579 -- Restore the original state of the scope stack
586 end Current_Anonymous_Master
;
588 --------------------------------
589 -- Displace_Allocator_Pointer --
590 --------------------------------
592 procedure Displace_Allocator_Pointer
(N
: Node_Id
) is
593 Loc
: constant Source_Ptr
:= Sloc
(N
);
594 Orig_Node
: constant Node_Id
:= Original_Node
(N
);
600 -- Do nothing in case of VM targets: the virtual machine will handle
601 -- interfaces directly.
603 if not Tagged_Type_Expansion
then
607 pragma Assert
(Nkind
(N
) = N_Identifier
608 and then Nkind
(Orig_Node
) = N_Allocator
);
610 PtrT
:= Etype
(Orig_Node
);
611 Dtyp
:= Available_View
(Designated_Type
(PtrT
));
612 Etyp
:= Etype
(Expression
(Orig_Node
));
614 if Is_Class_Wide_Type
(Dtyp
) and then Is_Interface
(Dtyp
) then
616 -- If the type of the allocator expression is not an interface type
617 -- we can generate code to reference the record component containing
618 -- the pointer to the secondary dispatch table.
620 if not Is_Interface
(Etyp
) then
622 Saved_Typ
: constant Entity_Id
:= Etype
(Orig_Node
);
625 -- 1) Get access to the allocated object
628 Make_Explicit_Dereference
(Loc
, Relocate_Node
(N
)));
632 -- 2) Add the conversion to displace the pointer to reference
633 -- the secondary dispatch table.
635 Rewrite
(N
, Convert_To
(Dtyp
, Relocate_Node
(N
)));
636 Analyze_And_Resolve
(N
, Dtyp
);
638 -- 3) The 'access to the secondary dispatch table will be used
639 -- as the value returned by the allocator.
642 Make_Attribute_Reference
(Loc
,
643 Prefix
=> Relocate_Node
(N
),
644 Attribute_Name
=> Name_Access
));
645 Set_Etype
(N
, Saved_Typ
);
649 -- If the type of the allocator expression is an interface type we
650 -- generate a run-time call to displace "this" to reference the
651 -- component containing the pointer to the secondary dispatch table
652 -- or else raise Constraint_Error if the actual object does not
653 -- implement the target interface. This case corresponds to the
654 -- following example:
656 -- function Op (Obj : Iface_1'Class) return access Iface_2'Class is
658 -- return new Iface_2'Class'(Obj);
663 Unchecked_Convert_To
(PtrT
,
664 Make_Function_Call
(Loc
,
665 Name
=> New_Occurrence_Of
(RTE
(RE_Displace
), Loc
),
666 Parameter_Associations
=> New_List
(
667 Unchecked_Convert_To
(RTE
(RE_Address
),
673 (Access_Disp_Table
(Etype
(Base_Type
(Dtyp
))))),
675 Analyze_And_Resolve
(N
, PtrT
);
678 end Displace_Allocator_Pointer
;
680 ---------------------------------
681 -- Expand_Allocator_Expression --
682 ---------------------------------
684 procedure Expand_Allocator_Expression
(N
: Node_Id
) is
685 Loc
: constant Source_Ptr
:= Sloc
(N
);
686 Exp
: constant Node_Id
:= Expression
(Expression
(N
));
687 PtrT
: constant Entity_Id
:= Etype
(N
);
688 DesigT
: constant Entity_Id
:= Designated_Type
(PtrT
);
690 procedure Apply_Accessibility_Check
692 Built_In_Place
: Boolean := False);
693 -- Ada 2005 (AI-344): For an allocator with a class-wide designated
694 -- type, generate an accessibility check to verify that the level of the
695 -- type of the created object is not deeper than the level of the access
696 -- type. If the type of the qualified expression is class-wide, then
697 -- always generate the check (except in the case where it is known to be
698 -- unnecessary, see comment below). Otherwise, only generate the check
699 -- if the level of the qualified expression type is statically deeper
700 -- than the access type.
702 -- Although the static accessibility will generally have been performed
703 -- as a legality check, it won't have been done in cases where the
704 -- allocator appears in generic body, so a run-time check is needed in
705 -- general. One special case is when the access type is declared in the
706 -- same scope as the class-wide allocator, in which case the check can
707 -- never fail, so it need not be generated.
709 -- As an open issue, there seem to be cases where the static level
710 -- associated with the class-wide object's underlying type is not
711 -- sufficient to perform the proper accessibility check, such as for
712 -- allocators in nested subprograms or accept statements initialized by
713 -- class-wide formals when the actual originates outside at a deeper
714 -- static level. The nested subprogram case might require passing
715 -- accessibility levels along with class-wide parameters, and the task
716 -- case seems to be an actual gap in the language rules that needs to
717 -- be fixed by the ARG. ???
719 -------------------------------
720 -- Apply_Accessibility_Check --
721 -------------------------------
723 procedure Apply_Accessibility_Check
725 Built_In_Place
: Boolean := False)
727 Pool_Id
: constant Entity_Id
:= Associated_Storage_Pool
(PtrT
);
735 if Ada_Version
>= Ada_2005
736 and then Is_Class_Wide_Type
(DesigT
)
737 and then (Tagged_Type_Expansion
or else VM_Target
/= No_VM
)
738 and then not Scope_Suppress
.Suppress
(Accessibility_Check
)
740 (Type_Access_Level
(Etype
(Exp
)) > Type_Access_Level
(PtrT
)
742 (Is_Class_Wide_Type
(Etype
(Exp
))
743 and then Scope
(PtrT
) /= Current_Scope
))
745 -- If the allocator was built in place, Ref is already a reference
746 -- to the access object initialized to the result of the allocator
747 -- (see Exp_Ch6.Make_Build_In_Place_Call_In_Allocator). We call
748 -- Remove_Side_Effects for cases where the build-in-place call may
749 -- still be the prefix of the reference (to avoid generating
750 -- duplicate calls). Otherwise, it is the entity associated with
751 -- the object containing the address of the allocated object.
753 if Built_In_Place
then
754 Remove_Side_Effects
(Ref
);
755 Obj_Ref
:= New_Copy_Tree
(Ref
);
757 Obj_Ref
:= New_Occurrence_Of
(Ref
, Loc
);
760 -- For access to interface types we must generate code to displace
761 -- the pointer to the base of the object since the subsequent code
762 -- references components located in the TSD of the object (which
763 -- is associated with the primary dispatch table --see a-tags.ads)
764 -- and also generates code invoking Free, which requires also a
765 -- reference to the base of the unallocated object.
767 if Is_Interface
(DesigT
) and then Tagged_Type_Expansion
then
769 Unchecked_Convert_To
(Etype
(Obj_Ref
),
770 Make_Function_Call
(Loc
,
772 New_Occurrence_Of
(RTE
(RE_Base_Address
), Loc
),
773 Parameter_Associations
=> New_List
(
774 Unchecked_Convert_To
(RTE
(RE_Address
),
775 New_Copy_Tree
(Obj_Ref
)))));
778 -- Step 1: Create the object clean up code
782 -- Deallocate the object if the accessibility check fails. This
783 -- is done only on targets or profiles that support deallocation.
787 if RTE_Available
(RE_Free
) then
788 Free_Stmt
:= Make_Free_Statement
(Loc
, New_Copy_Tree
(Obj_Ref
));
789 Set_Storage_Pool
(Free_Stmt
, Pool_Id
);
791 Append_To
(Stmts
, Free_Stmt
);
793 -- The target or profile cannot deallocate objects
799 -- Finalize the object if applicable. Generate:
801 -- [Deep_]Finalize (Obj_Ref.all);
803 if Needs_Finalization
(DesigT
) then
807 Make_Explicit_Dereference
(Loc
, New_Copy
(Obj_Ref
)),
810 -- When the target or profile supports deallocation, wrap the
811 -- finalization call in a block to ensure proper deallocation
812 -- even if finalization fails. Generate:
822 if Present
(Free_Stmt
) then
824 Make_Block_Statement
(Loc
,
825 Handled_Statement_Sequence
=>
826 Make_Handled_Sequence_Of_Statements
(Loc
,
827 Statements
=> New_List
(Fin_Call
),
829 Exception_Handlers
=> New_List
(
830 Make_Exception_Handler
(Loc
,
831 Exception_Choices
=> New_List
(
832 Make_Others_Choice
(Loc
)),
834 Statements
=> New_List
(
835 New_Copy_Tree
(Free_Stmt
),
836 Make_Raise_Statement
(Loc
))))));
839 Prepend_To
(Stmts
, Fin_Call
);
842 -- Signal the accessibility failure through a Program_Error
845 Make_Raise_Program_Error
(Loc
,
846 Condition
=> New_Occurrence_Of
(Standard_True
, Loc
),
847 Reason
=> PE_Accessibility_Check_Failed
));
849 -- Step 2: Create the accessibility comparison
855 Make_Attribute_Reference
(Loc
,
857 Attribute_Name
=> Name_Tag
);
859 -- For tagged types, determine the accessibility level by looking
860 -- at the type specific data of the dispatch table. Generate:
862 -- Type_Specific_Data (Address (Ref'Tag)).Access_Level
864 if Tagged_Type_Expansion
then
865 Cond
:= Build_Get_Access_Level
(Loc
, Obj_Ref
);
867 -- Use a runtime call to determine the accessibility level when
868 -- compiling on virtual machine targets. Generate:
870 -- Get_Access_Level (Ref'Tag)
874 Make_Function_Call
(Loc
,
876 New_Occurrence_Of
(RTE
(RE_Get_Access_Level
), Loc
),
877 Parameter_Associations
=> New_List
(Obj_Ref
));
884 Make_Integer_Literal
(Loc
, Type_Access_Level
(PtrT
)));
886 -- Due to the complexity and side effects of the check, utilize an
887 -- if statement instead of the regular Program_Error circuitry.
890 Make_Implicit_If_Statement
(N
,
892 Then_Statements
=> Stmts
));
894 end Apply_Accessibility_Check
;
898 Aggr_In_Place
: constant Boolean := Is_Delayed_Aggregate
(Exp
);
899 Indic
: constant Node_Id
:= Subtype_Mark
(Expression
(N
));
900 T
: constant Entity_Id
:= Entity
(Indic
);
902 Tag_Assign
: Node_Id
;
906 TagT
: Entity_Id
:= Empty
;
907 -- Type used as source for tag assignment
909 TagR
: Node_Id
:= Empty
;
910 -- Target reference for tag assignment
912 -- Start of processing for Expand_Allocator_Expression
915 -- Handle call to C++ constructor
917 if Is_CPP_Constructor_Call
(Exp
) then
918 Make_CPP_Constructor_Call_In_Allocator
920 Function_Call
=> Exp
);
924 -- In the case of an Ada 2012 allocator whose initial value comes from a
925 -- function call, pass "the accessibility level determined by the point
926 -- of call" (AI05-0234) to the function. Conceptually, this belongs in
927 -- Expand_Call but it couldn't be done there (because the Etype of the
928 -- allocator wasn't set then) so we generate the parameter here. See
929 -- the Boolean variable Defer in (a block within) Expand_Call.
931 if Ada_Version
>= Ada_2012
and then Nkind
(Exp
) = N_Function_Call
then
936 if Nkind
(Name
(Exp
)) = N_Explicit_Dereference
then
937 Subp
:= Designated_Type
(Etype
(Prefix
(Name
(Exp
))));
939 Subp
:= Entity
(Name
(Exp
));
942 Subp
:= Ultimate_Alias
(Subp
);
944 if Present
(Extra_Accessibility_Of_Result
(Subp
)) then
945 Add_Extra_Actual_To_Call
946 (Subprogram_Call
=> Exp
,
947 Extra_Formal
=> Extra_Accessibility_Of_Result
(Subp
),
948 Extra_Actual
=> Dynamic_Accessibility_Level
(PtrT
));
953 -- Case of tagged type or type requiring finalization
955 if Is_Tagged_Type
(T
) or else Needs_Finalization
(T
) then
957 -- Ada 2005 (AI-318-02): If the initialization expression is a call
958 -- to a build-in-place function, then access to the allocated object
959 -- must be passed to the function. Currently we limit such functions
960 -- to those with constrained limited result subtypes, but eventually
961 -- we plan to expand the allowed forms of functions that are treated
962 -- as build-in-place.
964 if Ada_Version
>= Ada_2005
965 and then Is_Build_In_Place_Function_Call
(Exp
)
967 Make_Build_In_Place_Call_In_Allocator
(N
, Exp
);
968 Apply_Accessibility_Check
(N
, Built_In_Place
=> True);
972 -- Actions inserted before:
973 -- Temp : constant ptr_T := new T'(Expression);
974 -- Temp._tag = T'tag; -- when not class-wide
975 -- [Deep_]Adjust (Temp.all);
977 -- We analyze by hand the new internal allocator to avoid any
978 -- recursion and inappropriate call to Initialize.
980 -- We don't want to remove side effects when the expression must be
981 -- built in place. In the case of a build-in-place function call,
982 -- that could lead to a duplication of the call, which was already
983 -- substituted for the allocator.
985 if not Aggr_In_Place
then
986 Remove_Side_Effects
(Exp
);
989 Temp
:= Make_Temporary
(Loc
, 'P', N
);
991 -- For a class wide allocation generate the following code:
993 -- type Equiv_Record is record ... end record;
994 -- implicit subtype CW is <Class_Wide_Subytpe>;
995 -- temp : PtrT := new CW'(CW!(expr));
997 if Is_Class_Wide_Type
(T
) then
998 Expand_Subtype_From_Expr
(Empty
, T
, Indic
, Exp
);
1000 -- Ada 2005 (AI-251): If the expression is a class-wide interface
1001 -- object we generate code to move up "this" to reference the
1002 -- base of the object before allocating the new object.
1004 -- Note that Exp'Address is recursively expanded into a call
1005 -- to Base_Address (Exp.Tag)
1007 if Is_Class_Wide_Type
(Etype
(Exp
))
1008 and then Is_Interface
(Etype
(Exp
))
1009 and then Tagged_Type_Expansion
1013 Unchecked_Convert_To
(Entity
(Indic
),
1014 Make_Explicit_Dereference
(Loc
,
1015 Unchecked_Convert_To
(RTE
(RE_Tag_Ptr
),
1016 Make_Attribute_Reference
(Loc
,
1018 Attribute_Name
=> Name_Address
)))));
1022 Unchecked_Convert_To
(Entity
(Indic
), Exp
));
1025 Analyze_And_Resolve
(Expression
(N
), Entity
(Indic
));
1028 -- Processing for allocators returning non-interface types
1030 if not Is_Interface
(Directly_Designated_Type
(PtrT
)) then
1031 if Aggr_In_Place
then
1033 Make_Object_Declaration
(Loc
,
1034 Defining_Identifier
=> Temp
,
1035 Object_Definition
=> New_Occurrence_Of
(PtrT
, Loc
),
1037 Make_Allocator
(Loc
,
1039 New_Occurrence_Of
(Etype
(Exp
), Loc
)));
1041 -- Copy the Comes_From_Source flag for the allocator we just
1042 -- built, since logically this allocator is a replacement of
1043 -- the original allocator node. This is for proper handling of
1044 -- restriction No_Implicit_Heap_Allocations.
1046 Set_Comes_From_Source
1047 (Expression
(Temp_Decl
), Comes_From_Source
(N
));
1049 Set_No_Initialization
(Expression
(Temp_Decl
));
1050 Insert_Action
(N
, Temp_Decl
);
1052 Build_Allocate_Deallocate_Proc
(Temp_Decl
, True);
1053 Convert_Aggr_In_Allocator
(N
, Temp_Decl
, Exp
);
1055 -- Attach the object to the associated finalization master.
1056 -- This is done manually on .NET/JVM since those compilers do
1057 -- no support pools and can't benefit from internally generated
1058 -- Allocate / Deallocate procedures.
1060 if VM_Target
/= No_VM
1061 and then Is_Controlled
(DesigT
)
1062 and then Present
(Finalization_Master
(PtrT
))
1066 (Obj_Ref
=> New_Occurrence_Of
(Temp
, Loc
),
1071 Node
:= Relocate_Node
(N
);
1072 Set_Analyzed
(Node
);
1075 Make_Object_Declaration
(Loc
,
1076 Defining_Identifier
=> Temp
,
1077 Constant_Present
=> True,
1078 Object_Definition
=> New_Occurrence_Of
(PtrT
, Loc
),
1079 Expression
=> Node
);
1081 Insert_Action
(N
, Temp_Decl
);
1082 Build_Allocate_Deallocate_Proc
(Temp_Decl
, True);
1084 -- Attach the object to the associated finalization master.
1085 -- This is done manually on .NET/JVM since those compilers do
1086 -- no support pools and can't benefit from internally generated
1087 -- Allocate / Deallocate procedures.
1089 if VM_Target
/= No_VM
1090 and then Is_Controlled
(DesigT
)
1091 and then Present
(Finalization_Master
(PtrT
))
1095 (Obj_Ref
=> New_Occurrence_Of
(Temp
, Loc
),
1100 -- Ada 2005 (AI-251): Handle allocators whose designated type is an
1101 -- interface type. In this case we use the type of the qualified
1102 -- expression to allocate the object.
1106 Def_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
1111 Make_Full_Type_Declaration
(Loc
,
1112 Defining_Identifier
=> Def_Id
,
1114 Make_Access_To_Object_Definition
(Loc
,
1115 All_Present
=> True,
1116 Null_Exclusion_Present
=> False,
1118 Is_Access_Constant
(Etype
(N
)),
1119 Subtype_Indication
=>
1120 New_Occurrence_Of
(Etype
(Exp
), Loc
)));
1122 Insert_Action
(N
, New_Decl
);
1124 -- Inherit the allocation-related attributes from the original
1127 Set_Finalization_Master
(Def_Id
, Finalization_Master
(PtrT
));
1129 Set_Associated_Storage_Pool
(Def_Id
,
1130 Associated_Storage_Pool
(PtrT
));
1132 -- Declare the object using the previous type declaration
1134 if Aggr_In_Place
then
1136 Make_Object_Declaration
(Loc
,
1137 Defining_Identifier
=> Temp
,
1138 Object_Definition
=> New_Occurrence_Of
(Def_Id
, Loc
),
1140 Make_Allocator
(Loc
,
1141 New_Occurrence_Of
(Etype
(Exp
), Loc
)));
1143 -- Copy the Comes_From_Source flag for the allocator we just
1144 -- built, since logically this allocator is a replacement of
1145 -- the original allocator node. This is for proper handling
1146 -- of restriction No_Implicit_Heap_Allocations.
1148 Set_Comes_From_Source
1149 (Expression
(Temp_Decl
), Comes_From_Source
(N
));
1151 Set_No_Initialization
(Expression
(Temp_Decl
));
1152 Insert_Action
(N
, Temp_Decl
);
1154 Build_Allocate_Deallocate_Proc
(Temp_Decl
, True);
1155 Convert_Aggr_In_Allocator
(N
, Temp_Decl
, Exp
);
1158 Node
:= Relocate_Node
(N
);
1159 Set_Analyzed
(Node
);
1162 Make_Object_Declaration
(Loc
,
1163 Defining_Identifier
=> Temp
,
1164 Constant_Present
=> True,
1165 Object_Definition
=> New_Occurrence_Of
(Def_Id
, Loc
),
1166 Expression
=> Node
);
1168 Insert_Action
(N
, Temp_Decl
);
1169 Build_Allocate_Deallocate_Proc
(Temp_Decl
, True);
1172 -- Generate an additional object containing the address of the
1173 -- returned object. The type of this second object declaration
1174 -- is the correct type required for the common processing that
1175 -- is still performed by this subprogram. The displacement of
1176 -- this pointer to reference the component associated with the
1177 -- interface type will be done at the end of common processing.
1180 Make_Object_Declaration
(Loc
,
1181 Defining_Identifier
=> Make_Temporary
(Loc
, 'P'),
1182 Object_Definition
=> New_Occurrence_Of
(PtrT
, Loc
),
1184 Unchecked_Convert_To
(PtrT
,
1185 New_Occurrence_Of
(Temp
, Loc
)));
1187 Insert_Action
(N
, New_Decl
);
1189 Temp_Decl
:= New_Decl
;
1190 Temp
:= Defining_Identifier
(New_Decl
);
1194 Apply_Accessibility_Check
(Temp
);
1196 -- Generate the tag assignment
1198 -- Suppress the tag assignment when VM_Target because VM tags are
1199 -- represented implicitly in objects.
1201 if not Tagged_Type_Expansion
then
1204 -- Ada 2005 (AI-251): Suppress the tag assignment with class-wide
1205 -- interface objects because in this case the tag does not change.
1207 elsif Is_Interface
(Directly_Designated_Type
(Etype
(N
))) then
1208 pragma Assert
(Is_Class_Wide_Type
1209 (Directly_Designated_Type
(Etype
(N
))));
1212 elsif Is_Tagged_Type
(T
) and then not Is_Class_Wide_Type
(T
) then
1214 TagR
:= New_Occurrence_Of
(Temp
, Loc
);
1216 elsif Is_Private_Type
(T
)
1217 and then Is_Tagged_Type
(Underlying_Type
(T
))
1219 TagT
:= Underlying_Type
(T
);
1221 Unchecked_Convert_To
(Underlying_Type
(T
),
1222 Make_Explicit_Dereference
(Loc
,
1223 Prefix
=> New_Occurrence_Of
(Temp
, Loc
)));
1226 if Present
(TagT
) then
1228 Full_T
: constant Entity_Id
:= Underlying_Type
(TagT
);
1232 Make_Assignment_Statement
(Loc
,
1234 Make_Selected_Component
(Loc
,
1238 (First_Tag_Component
(Full_T
), Loc
)),
1241 Unchecked_Convert_To
(RTE
(RE_Tag
),
1244 (First_Elmt
(Access_Disp_Table
(Full_T
))), Loc
)));
1247 -- The previous assignment has to be done in any case
1249 Set_Assignment_OK
(Name
(Tag_Assign
));
1250 Insert_Action
(N
, Tag_Assign
);
1253 if Needs_Finalization
(DesigT
) and then Needs_Finalization
(T
) then
1255 -- Generate an Adjust call if the object will be moved. In Ada
1256 -- 2005, the object may be inherently limited, in which case
1257 -- there is no Adjust procedure, and the object is built in
1258 -- place. In Ada 95, the object can be limited but not
1259 -- inherently limited if this allocator came from a return
1260 -- statement (we're allocating the result on the secondary
1261 -- stack). In that case, the object will be moved, so we _do_
1264 if not Aggr_In_Place
1265 and then not Is_Limited_View
(T
)
1269 -- An unchecked conversion is needed in the classwide case
1270 -- because the designated type can be an ancestor of the
1271 -- subtype mark of the allocator.
1275 Unchecked_Convert_To
(T
,
1276 Make_Explicit_Dereference
(Loc
,
1277 Prefix
=> New_Occurrence_Of
(Temp
, Loc
))),
1282 -- Set_Finalize_Address (<PtrT>FM, <T>FD'Unrestricted_Access);
1284 -- Do not generate this call in the following cases:
1286 -- * .NET/JVM - these targets do not support address arithmetic
1287 -- and unchecked conversion, key elements of Finalize_Address.
1289 -- * CodePeer mode - TSS primitive Finalize_Address is not
1290 -- created in this mode.
1292 if VM_Target
= No_VM
1293 and then not CodePeer_Mode
1294 and then Present
(Finalization_Master
(PtrT
))
1295 and then Present
(Temp_Decl
)
1296 and then Nkind
(Expression
(Temp_Decl
)) = N_Allocator
1299 Make_Set_Finalize_Address_Call
1306 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
1307 Analyze_And_Resolve
(N
, PtrT
);
1309 -- Ada 2005 (AI-251): Displace the pointer to reference the record
1310 -- component containing the secondary dispatch table of the interface
1313 if Is_Interface
(Directly_Designated_Type
(PtrT
)) then
1314 Displace_Allocator_Pointer
(N
);
1317 elsif Aggr_In_Place
then
1318 Temp
:= Make_Temporary
(Loc
, 'P', N
);
1320 Make_Object_Declaration
(Loc
,
1321 Defining_Identifier
=> Temp
,
1322 Object_Definition
=> New_Occurrence_Of
(PtrT
, Loc
),
1324 Make_Allocator
(Loc
,
1325 Expression
=> New_Occurrence_Of
(Etype
(Exp
), Loc
)));
1327 -- Copy the Comes_From_Source flag for the allocator we just built,
1328 -- since logically this allocator is a replacement of the original
1329 -- allocator node. This is for proper handling of restriction
1330 -- No_Implicit_Heap_Allocations.
1332 Set_Comes_From_Source
1333 (Expression
(Temp_Decl
), Comes_From_Source
(N
));
1335 Set_No_Initialization
(Expression
(Temp_Decl
));
1336 Insert_Action
(N
, Temp_Decl
);
1338 Build_Allocate_Deallocate_Proc
(Temp_Decl
, True);
1339 Convert_Aggr_In_Allocator
(N
, Temp_Decl
, Exp
);
1341 -- Attach the object to the associated finalization master. Thisis
1342 -- done manually on .NET/JVM since those compilers do no support
1343 -- pools and cannot benefit from internally generated Allocate and
1344 -- Deallocate procedures.
1346 if VM_Target
/= No_VM
1347 and then Is_Controlled
(DesigT
)
1348 and then Present
(Finalization_Master
(PtrT
))
1352 (Obj_Ref
=> New_Occurrence_Of
(Temp
, Loc
),
1356 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
1357 Analyze_And_Resolve
(N
, PtrT
);
1359 elsif Is_Access_Type
(T
) and then Can_Never_Be_Null
(T
) then
1360 Install_Null_Excluding_Check
(Exp
);
1362 elsif Is_Access_Type
(DesigT
)
1363 and then Nkind
(Exp
) = N_Allocator
1364 and then Nkind
(Expression
(Exp
)) /= N_Qualified_Expression
1366 -- Apply constraint to designated subtype indication
1368 Apply_Constraint_Check
1369 (Expression
(Exp
), Designated_Type
(DesigT
), No_Sliding
=> True);
1371 if Nkind
(Expression
(Exp
)) = N_Raise_Constraint_Error
then
1373 -- Propagate constraint_error to enclosing allocator
1375 Rewrite
(Exp
, New_Copy
(Expression
(Exp
)));
1379 Build_Allocate_Deallocate_Proc
(N
, True);
1382 -- type A is access T1;
1383 -- X : A := new T2'(...);
1384 -- T1 and T2 can be different subtypes, and we might need to check
1385 -- both constraints. First check against the type of the qualified
1388 Apply_Constraint_Check
(Exp
, T
, No_Sliding
=> True);
1390 if Do_Range_Check
(Exp
) then
1391 Generate_Range_Check
(Exp
, DesigT
, CE_Range_Check_Failed
);
1394 -- A check is also needed in cases where the designated subtype is
1395 -- constrained and differs from the subtype given in the qualified
1396 -- expression. Note that the check on the qualified expression does
1397 -- not allow sliding, but this check does (a relaxation from Ada 83).
1399 if Is_Constrained
(DesigT
)
1400 and then not Subtypes_Statically_Match
(T
, DesigT
)
1402 Apply_Constraint_Check
1403 (Exp
, DesigT
, No_Sliding
=> False);
1405 if Do_Range_Check
(Exp
) then
1406 Generate_Range_Check
(Exp
, DesigT
, CE_Range_Check_Failed
);
1410 -- For an access to unconstrained packed array, GIGI needs to see an
1411 -- expression with a constrained subtype in order to compute the
1412 -- proper size for the allocator.
1414 if Is_Array_Type
(T
)
1415 and then not Is_Constrained
(T
)
1416 and then Is_Packed
(T
)
1419 ConstrT
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
1420 Internal_Exp
: constant Node_Id
:= Relocate_Node
(Exp
);
1423 Make_Subtype_Declaration
(Loc
,
1424 Defining_Identifier
=> ConstrT
,
1425 Subtype_Indication
=>
1426 Make_Subtype_From_Expr
(Internal_Exp
, T
)));
1427 Freeze_Itype
(ConstrT
, Exp
);
1428 Rewrite
(Exp
, OK_Convert_To
(ConstrT
, Internal_Exp
));
1432 -- Ada 2005 (AI-318-02): If the initialization expression is a call
1433 -- to a build-in-place function, then access to the allocated object
1434 -- must be passed to the function. Currently we limit such functions
1435 -- to those with constrained limited result subtypes, but eventually
1436 -- we plan to expand the allowed forms of functions that are treated
1437 -- as build-in-place.
1439 if Ada_Version
>= Ada_2005
1440 and then Is_Build_In_Place_Function_Call
(Exp
)
1442 Make_Build_In_Place_Call_In_Allocator
(N
, Exp
);
1447 when RE_Not_Available
=>
1449 end Expand_Allocator_Expression
;
1451 -----------------------------
1452 -- Expand_Array_Comparison --
1453 -----------------------------
1455 -- Expansion is only required in the case of array types. For the unpacked
1456 -- case, an appropriate runtime routine is called. For packed cases, and
1457 -- also in some other cases where a runtime routine cannot be called, the
1458 -- form of the expansion is:
1460 -- [body for greater_nn; boolean_expression]
1462 -- The body is built by Make_Array_Comparison_Op, and the form of the
1463 -- Boolean expression depends on the operator involved.
1465 procedure Expand_Array_Comparison
(N
: Node_Id
) is
1466 Loc
: constant Source_Ptr
:= Sloc
(N
);
1467 Op1
: Node_Id
:= Left_Opnd
(N
);
1468 Op2
: Node_Id
:= Right_Opnd
(N
);
1469 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
1470 Ctyp
: constant Entity_Id
:= Component_Type
(Typ1
);
1473 Func_Body
: Node_Id
;
1474 Func_Name
: Entity_Id
;
1478 Byte_Addressable
: constant Boolean := System_Storage_Unit
= Byte
'Size;
1479 -- True for byte addressable target
1481 function Length_Less_Than_4
(Opnd
: Node_Id
) return Boolean;
1482 -- Returns True if the length of the given operand is known to be less
1483 -- than 4. Returns False if this length is known to be four or greater
1484 -- or is not known at compile time.
1486 ------------------------
1487 -- Length_Less_Than_4 --
1488 ------------------------
1490 function Length_Less_Than_4
(Opnd
: Node_Id
) return Boolean is
1491 Otyp
: constant Entity_Id
:= Etype
(Opnd
);
1494 if Ekind
(Otyp
) = E_String_Literal_Subtype
then
1495 return String_Literal_Length
(Otyp
) < 4;
1499 Ityp
: constant Entity_Id
:= Etype
(First_Index
(Otyp
));
1500 Lo
: constant Node_Id
:= Type_Low_Bound
(Ityp
);
1501 Hi
: constant Node_Id
:= Type_High_Bound
(Ityp
);
1506 if Compile_Time_Known_Value
(Lo
) then
1507 Lov
:= Expr_Value
(Lo
);
1512 if Compile_Time_Known_Value
(Hi
) then
1513 Hiv
:= Expr_Value
(Hi
);
1518 return Hiv
< Lov
+ 3;
1521 end Length_Less_Than_4
;
1523 -- Start of processing for Expand_Array_Comparison
1526 -- Deal first with unpacked case, where we can call a runtime routine
1527 -- except that we avoid this for targets for which are not addressable
1528 -- by bytes, and for the JVM/CIL, since they do not support direct
1529 -- addressing of array components.
1531 if not Is_Bit_Packed_Array
(Typ1
)
1532 and then Byte_Addressable
1533 and then VM_Target
= No_VM
1535 -- The call we generate is:
1537 -- Compare_Array_xn[_Unaligned]
1538 -- (left'address, right'address, left'length, right'length) <op> 0
1540 -- x = U for unsigned, S for signed
1541 -- n = 8,16,32,64 for component size
1542 -- Add _Unaligned if length < 4 and component size is 8.
1543 -- <op> is the standard comparison operator
1545 if Component_Size
(Typ1
) = 8 then
1546 if Length_Less_Than_4
(Op1
)
1548 Length_Less_Than_4
(Op2
)
1550 if Is_Unsigned_Type
(Ctyp
) then
1551 Comp
:= RE_Compare_Array_U8_Unaligned
;
1553 Comp
:= RE_Compare_Array_S8_Unaligned
;
1557 if Is_Unsigned_Type
(Ctyp
) then
1558 Comp
:= RE_Compare_Array_U8
;
1560 Comp
:= RE_Compare_Array_S8
;
1564 elsif Component_Size
(Typ1
) = 16 then
1565 if Is_Unsigned_Type
(Ctyp
) then
1566 Comp
:= RE_Compare_Array_U16
;
1568 Comp
:= RE_Compare_Array_S16
;
1571 elsif Component_Size
(Typ1
) = 32 then
1572 if Is_Unsigned_Type
(Ctyp
) then
1573 Comp
:= RE_Compare_Array_U32
;
1575 Comp
:= RE_Compare_Array_S32
;
1578 else pragma Assert
(Component_Size
(Typ1
) = 64);
1579 if Is_Unsigned_Type
(Ctyp
) then
1580 Comp
:= RE_Compare_Array_U64
;
1582 Comp
:= RE_Compare_Array_S64
;
1586 Remove_Side_Effects
(Op1
, Name_Req
=> True);
1587 Remove_Side_Effects
(Op2
, Name_Req
=> True);
1590 Make_Function_Call
(Sloc
(Op1
),
1591 Name
=> New_Occurrence_Of
(RTE
(Comp
), Loc
),
1593 Parameter_Associations
=> New_List
(
1594 Make_Attribute_Reference
(Loc
,
1595 Prefix
=> Relocate_Node
(Op1
),
1596 Attribute_Name
=> Name_Address
),
1598 Make_Attribute_Reference
(Loc
,
1599 Prefix
=> Relocate_Node
(Op2
),
1600 Attribute_Name
=> Name_Address
),
1602 Make_Attribute_Reference
(Loc
,
1603 Prefix
=> Relocate_Node
(Op1
),
1604 Attribute_Name
=> Name_Length
),
1606 Make_Attribute_Reference
(Loc
,
1607 Prefix
=> Relocate_Node
(Op2
),
1608 Attribute_Name
=> Name_Length
))));
1611 Make_Integer_Literal
(Sloc
(Op2
),
1614 Analyze_And_Resolve
(Op1
, Standard_Integer
);
1615 Analyze_And_Resolve
(Op2
, Standard_Integer
);
1619 -- Cases where we cannot make runtime call
1621 -- For (a <= b) we convert to not (a > b)
1623 if Chars
(N
) = Name_Op_Le
then
1629 Right_Opnd
=> Op2
)));
1630 Analyze_And_Resolve
(N
, Standard_Boolean
);
1633 -- For < the Boolean expression is
1634 -- greater__nn (op2, op1)
1636 elsif Chars
(N
) = Name_Op_Lt
then
1637 Func_Body
:= Make_Array_Comparison_Op
(Typ1
, N
);
1641 Op1
:= Right_Opnd
(N
);
1642 Op2
:= Left_Opnd
(N
);
1644 -- For (a >= b) we convert to not (a < b)
1646 elsif Chars
(N
) = Name_Op_Ge
then
1652 Right_Opnd
=> Op2
)));
1653 Analyze_And_Resolve
(N
, Standard_Boolean
);
1656 -- For > the Boolean expression is
1657 -- greater__nn (op1, op2)
1660 pragma Assert
(Chars
(N
) = Name_Op_Gt
);
1661 Func_Body
:= Make_Array_Comparison_Op
(Typ1
, N
);
1664 Func_Name
:= Defining_Unit_Name
(Specification
(Func_Body
));
1666 Make_Function_Call
(Loc
,
1667 Name
=> New_Occurrence_Of
(Func_Name
, Loc
),
1668 Parameter_Associations
=> New_List
(Op1
, Op2
));
1670 Insert_Action
(N
, Func_Body
);
1672 Analyze_And_Resolve
(N
, Standard_Boolean
);
1675 when RE_Not_Available
=>
1677 end Expand_Array_Comparison
;
1679 ---------------------------
1680 -- Expand_Array_Equality --
1681 ---------------------------
1683 -- Expand an equality function for multi-dimensional arrays. Here is an
1684 -- example of such a function for Nb_Dimension = 2
1686 -- function Enn (A : atyp; B : btyp) return boolean is
1688 -- if (A'length (1) = 0 or else A'length (2) = 0)
1690 -- (B'length (1) = 0 or else B'length (2) = 0)
1692 -- return True; -- RM 4.5.2(22)
1695 -- if A'length (1) /= B'length (1)
1697 -- A'length (2) /= B'length (2)
1699 -- return False; -- RM 4.5.2(23)
1703 -- A1 : Index_T1 := A'first (1);
1704 -- B1 : Index_T1 := B'first (1);
1708 -- A2 : Index_T2 := A'first (2);
1709 -- B2 : Index_T2 := B'first (2);
1712 -- if A (A1, A2) /= B (B1, B2) then
1716 -- exit when A2 = A'last (2);
1717 -- A2 := Index_T2'succ (A2);
1718 -- B2 := Index_T2'succ (B2);
1722 -- exit when A1 = A'last (1);
1723 -- A1 := Index_T1'succ (A1);
1724 -- B1 := Index_T1'succ (B1);
1731 -- Note on the formal types used (atyp and btyp). If either of the arrays
1732 -- is of a private type, we use the underlying type, and do an unchecked
1733 -- conversion of the actual. If either of the arrays has a bound depending
1734 -- on a discriminant, then we use the base type since otherwise we have an
1735 -- escaped discriminant in the function.
1737 -- If both arrays are constrained and have the same bounds, we can generate
1738 -- a loop with an explicit iteration scheme using a 'Range attribute over
1741 function Expand_Array_Equality
1746 Typ
: Entity_Id
) return Node_Id
1748 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
1749 Decls
: constant List_Id
:= New_List
;
1750 Index_List1
: constant List_Id
:= New_List
;
1751 Index_List2
: constant List_Id
:= New_List
;
1755 Func_Name
: Entity_Id
;
1756 Func_Body
: Node_Id
;
1758 A
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uA
);
1759 B
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uB
);
1763 -- The parameter types to be used for the formals
1768 Num
: Int
) return Node_Id
;
1769 -- This builds the attribute reference Arr'Nam (Expr)
1771 function Component_Equality
(Typ
: Entity_Id
) return Node_Id
;
1772 -- Create one statement to compare corresponding components, designated
1773 -- by a full set of indexes.
1775 function Get_Arg_Type
(N
: Node_Id
) return Entity_Id
;
1776 -- Given one of the arguments, computes the appropriate type to be used
1777 -- for that argument in the corresponding function formal
1779 function Handle_One_Dimension
1781 Index
: Node_Id
) return Node_Id
;
1782 -- This procedure returns the following code
1785 -- Bn : Index_T := B'First (N);
1789 -- exit when An = A'Last (N);
1790 -- An := Index_T'Succ (An)
1791 -- Bn := Index_T'Succ (Bn)
1795 -- If both indexes are constrained and identical, the procedure
1796 -- returns a simpler loop:
1798 -- for An in A'Range (N) loop
1802 -- N is the dimension for which we are generating a loop. Index is the
1803 -- N'th index node, whose Etype is Index_Type_n in the above code. The
1804 -- xxx statement is either the loop or declare for the next dimension
1805 -- or if this is the last dimension the comparison of corresponding
1806 -- components of the arrays.
1808 -- The actual way the code works is to return the comparison of
1809 -- corresponding components for the N+1 call. That's neater.
1811 function Test_Empty_Arrays
return Node_Id
;
1812 -- This function constructs the test for both arrays being empty
1813 -- (A'length (1) = 0 or else A'length (2) = 0 or else ...)
1815 -- (B'length (1) = 0 or else B'length (2) = 0 or else ...)
1817 function Test_Lengths_Correspond
return Node_Id
;
1818 -- This function constructs the test for arrays having different lengths
1819 -- in at least one index position, in which case the resulting code is:
1821 -- A'length (1) /= B'length (1)
1823 -- A'length (2) /= B'length (2)
1834 Num
: Int
) return Node_Id
1838 Make_Attribute_Reference
(Loc
,
1839 Attribute_Name
=> Nam
,
1840 Prefix
=> New_Occurrence_Of
(Arr
, Loc
),
1841 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, Num
)));
1844 ------------------------
1845 -- Component_Equality --
1846 ------------------------
1848 function Component_Equality
(Typ
: Entity_Id
) return Node_Id
is
1853 -- if a(i1...) /= b(j1...) then return false; end if;
1856 Make_Indexed_Component
(Loc
,
1857 Prefix
=> Make_Identifier
(Loc
, Chars
(A
)),
1858 Expressions
=> Index_List1
);
1861 Make_Indexed_Component
(Loc
,
1862 Prefix
=> Make_Identifier
(Loc
, Chars
(B
)),
1863 Expressions
=> Index_List2
);
1865 Test
:= Expand_Composite_Equality
1866 (Nod
, Component_Type
(Typ
), L
, R
, Decls
);
1868 -- If some (sub)component is an unchecked_union, the whole operation
1869 -- will raise program error.
1871 if Nkind
(Test
) = N_Raise_Program_Error
then
1873 -- This node is going to be inserted at a location where a
1874 -- statement is expected: clear its Etype so analysis will set
1875 -- it to the expected Standard_Void_Type.
1877 Set_Etype
(Test
, Empty
);
1882 Make_Implicit_If_Statement
(Nod
,
1883 Condition
=> Make_Op_Not
(Loc
, Right_Opnd
=> Test
),
1884 Then_Statements
=> New_List
(
1885 Make_Simple_Return_Statement
(Loc
,
1886 Expression
=> New_Occurrence_Of
(Standard_False
, Loc
))));
1888 end Component_Equality
;
1894 function Get_Arg_Type
(N
: Node_Id
) return Entity_Id
is
1905 T
:= Underlying_Type
(T
);
1907 X
:= First_Index
(T
);
1908 while Present
(X
) loop
1909 if Denotes_Discriminant
(Type_Low_Bound
(Etype
(X
)))
1911 Denotes_Discriminant
(Type_High_Bound
(Etype
(X
)))
1924 --------------------------
1925 -- Handle_One_Dimension --
1926 ---------------------------
1928 function Handle_One_Dimension
1930 Index
: Node_Id
) return Node_Id
1932 Need_Separate_Indexes
: constant Boolean :=
1933 Ltyp
/= Rtyp
or else not Is_Constrained
(Ltyp
);
1934 -- If the index types are identical, and we are working with
1935 -- constrained types, then we can use the same index for both
1938 An
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
1941 Index_T
: Entity_Id
;
1946 if N
> Number_Dimensions
(Ltyp
) then
1947 return Component_Equality
(Ltyp
);
1950 -- Case where we generate a loop
1952 Index_T
:= Base_Type
(Etype
(Index
));
1954 if Need_Separate_Indexes
then
1955 Bn
:= Make_Temporary
(Loc
, 'B');
1960 Append
(New_Occurrence_Of
(An
, Loc
), Index_List1
);
1961 Append
(New_Occurrence_Of
(Bn
, Loc
), Index_List2
);
1963 Stm_List
:= New_List
(
1964 Handle_One_Dimension
(N
+ 1, Next_Index
(Index
)));
1966 if Need_Separate_Indexes
then
1968 -- Generate guard for loop, followed by increments of indexes
1970 Append_To
(Stm_List
,
1971 Make_Exit_Statement
(Loc
,
1974 Left_Opnd
=> New_Occurrence_Of
(An
, Loc
),
1975 Right_Opnd
=> Arr_Attr
(A
, Name_Last
, N
))));
1977 Append_To
(Stm_List
,
1978 Make_Assignment_Statement
(Loc
,
1979 Name
=> New_Occurrence_Of
(An
, Loc
),
1981 Make_Attribute_Reference
(Loc
,
1982 Prefix
=> New_Occurrence_Of
(Index_T
, Loc
),
1983 Attribute_Name
=> Name_Succ
,
1984 Expressions
=> New_List
(
1985 New_Occurrence_Of
(An
, Loc
)))));
1987 Append_To
(Stm_List
,
1988 Make_Assignment_Statement
(Loc
,
1989 Name
=> New_Occurrence_Of
(Bn
, Loc
),
1991 Make_Attribute_Reference
(Loc
,
1992 Prefix
=> New_Occurrence_Of
(Index_T
, Loc
),
1993 Attribute_Name
=> Name_Succ
,
1994 Expressions
=> New_List
(
1995 New_Occurrence_Of
(Bn
, Loc
)))));
1998 -- If separate indexes, we need a declare block for An and Bn, and a
1999 -- loop without an iteration scheme.
2001 if Need_Separate_Indexes
then
2003 Make_Implicit_Loop_Statement
(Nod
, Statements
=> Stm_List
);
2006 Make_Block_Statement
(Loc
,
2007 Declarations
=> New_List
(
2008 Make_Object_Declaration
(Loc
,
2009 Defining_Identifier
=> An
,
2010 Object_Definition
=> New_Occurrence_Of
(Index_T
, Loc
),
2011 Expression
=> Arr_Attr
(A
, Name_First
, N
)),
2013 Make_Object_Declaration
(Loc
,
2014 Defining_Identifier
=> Bn
,
2015 Object_Definition
=> New_Occurrence_Of
(Index_T
, Loc
),
2016 Expression
=> Arr_Attr
(B
, Name_First
, N
))),
2018 Handled_Statement_Sequence
=>
2019 Make_Handled_Sequence_Of_Statements
(Loc
,
2020 Statements
=> New_List
(Loop_Stm
)));
2022 -- If no separate indexes, return loop statement with explicit
2023 -- iteration scheme on its own
2027 Make_Implicit_Loop_Statement
(Nod
,
2028 Statements
=> Stm_List
,
2030 Make_Iteration_Scheme
(Loc
,
2031 Loop_Parameter_Specification
=>
2032 Make_Loop_Parameter_Specification
(Loc
,
2033 Defining_Identifier
=> An
,
2034 Discrete_Subtype_Definition
=>
2035 Arr_Attr
(A
, Name_Range
, N
))));
2038 end Handle_One_Dimension
;
2040 -----------------------
2041 -- Test_Empty_Arrays --
2042 -----------------------
2044 function Test_Empty_Arrays
return Node_Id
is
2054 for J
in 1 .. Number_Dimensions
(Ltyp
) loop
2057 Left_Opnd
=> Arr_Attr
(A
, Name_Length
, J
),
2058 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0));
2062 Left_Opnd
=> Arr_Attr
(B
, Name_Length
, J
),
2063 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0));
2072 Left_Opnd
=> Relocate_Node
(Alist
),
2073 Right_Opnd
=> Atest
);
2077 Left_Opnd
=> Relocate_Node
(Blist
),
2078 Right_Opnd
=> Btest
);
2085 Right_Opnd
=> Blist
);
2086 end Test_Empty_Arrays
;
2088 -----------------------------
2089 -- Test_Lengths_Correspond --
2090 -----------------------------
2092 function Test_Lengths_Correspond
return Node_Id
is
2098 for J
in 1 .. Number_Dimensions
(Ltyp
) loop
2101 Left_Opnd
=> Arr_Attr
(A
, Name_Length
, J
),
2102 Right_Opnd
=> Arr_Attr
(B
, Name_Length
, J
));
2109 Left_Opnd
=> Relocate_Node
(Result
),
2110 Right_Opnd
=> Rtest
);
2115 end Test_Lengths_Correspond
;
2117 -- Start of processing for Expand_Array_Equality
2120 Ltyp
:= Get_Arg_Type
(Lhs
);
2121 Rtyp
:= Get_Arg_Type
(Rhs
);
2123 -- For now, if the argument types are not the same, go to the base type,
2124 -- since the code assumes that the formals have the same type. This is
2125 -- fixable in future ???
2127 if Ltyp
/= Rtyp
then
2128 Ltyp
:= Base_Type
(Ltyp
);
2129 Rtyp
:= Base_Type
(Rtyp
);
2130 pragma Assert
(Ltyp
= Rtyp
);
2133 -- Build list of formals for function
2135 Formals
:= New_List
(
2136 Make_Parameter_Specification
(Loc
,
2137 Defining_Identifier
=> A
,
2138 Parameter_Type
=> New_Occurrence_Of
(Ltyp
, Loc
)),
2140 Make_Parameter_Specification
(Loc
,
2141 Defining_Identifier
=> B
,
2142 Parameter_Type
=> New_Occurrence_Of
(Rtyp
, Loc
)));
2144 Func_Name
:= Make_Temporary
(Loc
, 'E');
2146 -- Build statement sequence for function
2149 Make_Subprogram_Body
(Loc
,
2151 Make_Function_Specification
(Loc
,
2152 Defining_Unit_Name
=> Func_Name
,
2153 Parameter_Specifications
=> Formals
,
2154 Result_Definition
=> New_Occurrence_Of
(Standard_Boolean
, Loc
)),
2156 Declarations
=> Decls
,
2158 Handled_Statement_Sequence
=>
2159 Make_Handled_Sequence_Of_Statements
(Loc
,
2160 Statements
=> New_List
(
2162 Make_Implicit_If_Statement
(Nod
,
2163 Condition
=> Test_Empty_Arrays
,
2164 Then_Statements
=> New_List
(
2165 Make_Simple_Return_Statement
(Loc
,
2167 New_Occurrence_Of
(Standard_True
, Loc
)))),
2169 Make_Implicit_If_Statement
(Nod
,
2170 Condition
=> Test_Lengths_Correspond
,
2171 Then_Statements
=> New_List
(
2172 Make_Simple_Return_Statement
(Loc
,
2173 Expression
=> New_Occurrence_Of
(Standard_False
, Loc
)))),
2175 Handle_One_Dimension
(1, First_Index
(Ltyp
)),
2177 Make_Simple_Return_Statement
(Loc
,
2178 Expression
=> New_Occurrence_Of
(Standard_True
, Loc
)))));
2180 Set_Has_Completion
(Func_Name
, True);
2181 Set_Is_Inlined
(Func_Name
);
2183 -- If the array type is distinct from the type of the arguments, it
2184 -- is the full view of a private type. Apply an unchecked conversion
2185 -- to insure that analysis of the call succeeds.
2195 or else Base_Type
(Etype
(Lhs
)) /= Base_Type
(Ltyp
)
2197 L
:= OK_Convert_To
(Ltyp
, Lhs
);
2201 or else Base_Type
(Etype
(Rhs
)) /= Base_Type
(Rtyp
)
2203 R
:= OK_Convert_To
(Rtyp
, Rhs
);
2206 Actuals
:= New_List
(L
, R
);
2209 Append_To
(Bodies
, Func_Body
);
2212 Make_Function_Call
(Loc
,
2213 Name
=> New_Occurrence_Of
(Func_Name
, Loc
),
2214 Parameter_Associations
=> Actuals
);
2215 end Expand_Array_Equality
;
2217 -----------------------------
2218 -- Expand_Boolean_Operator --
2219 -----------------------------
2221 -- Note that we first get the actual subtypes of the operands, since we
2222 -- always want to deal with types that have bounds.
2224 procedure Expand_Boolean_Operator
(N
: Node_Id
) is
2225 Typ
: constant Entity_Id
:= Etype
(N
);
2228 -- Special case of bit packed array where both operands are known to be
2229 -- properly aligned. In this case we use an efficient run time routine
2230 -- to carry out the operation (see System.Bit_Ops).
2232 if Is_Bit_Packed_Array
(Typ
)
2233 and then not Is_Possibly_Unaligned_Object
(Left_Opnd
(N
))
2234 and then not Is_Possibly_Unaligned_Object
(Right_Opnd
(N
))
2236 Expand_Packed_Boolean_Operator
(N
);
2240 -- For the normal non-packed case, the general expansion is to build
2241 -- function for carrying out the comparison (use Make_Boolean_Array_Op)
2242 -- and then inserting it into the tree. The original operator node is
2243 -- then rewritten as a call to this function. We also use this in the
2244 -- packed case if either operand is a possibly unaligned object.
2247 Loc
: constant Source_Ptr
:= Sloc
(N
);
2248 L
: constant Node_Id
:= Relocate_Node
(Left_Opnd
(N
));
2249 R
: constant Node_Id
:= Relocate_Node
(Right_Opnd
(N
));
2250 Func_Body
: Node_Id
;
2251 Func_Name
: Entity_Id
;
2254 Convert_To_Actual_Subtype
(L
);
2255 Convert_To_Actual_Subtype
(R
);
2256 Ensure_Defined
(Etype
(L
), N
);
2257 Ensure_Defined
(Etype
(R
), N
);
2258 Apply_Length_Check
(R
, Etype
(L
));
2260 if Nkind
(N
) = N_Op_Xor
then
2261 Silly_Boolean_Array_Xor_Test
(N
, Etype
(L
));
2264 if Nkind
(Parent
(N
)) = N_Assignment_Statement
2265 and then Safe_In_Place_Array_Op
(Name
(Parent
(N
)), L
, R
)
2267 Build_Boolean_Array_Proc_Call
(Parent
(N
), L
, R
);
2269 elsif Nkind
(Parent
(N
)) = N_Op_Not
2270 and then Nkind
(N
) = N_Op_And
2271 and then Safe_In_Place_Array_Op
(Name
(Parent
(Parent
(N
))), L
, R
)
2276 Func_Body
:= Make_Boolean_Array_Op
(Etype
(L
), N
);
2277 Func_Name
:= Defining_Unit_Name
(Specification
(Func_Body
));
2278 Insert_Action
(N
, Func_Body
);
2280 -- Now rewrite the expression with a call
2283 Make_Function_Call
(Loc
,
2284 Name
=> New_Occurrence_Of
(Func_Name
, Loc
),
2285 Parameter_Associations
=>
2288 Make_Type_Conversion
2289 (Loc
, New_Occurrence_Of
(Etype
(L
), Loc
), R
))));
2291 Analyze_And_Resolve
(N
, Typ
);
2294 end Expand_Boolean_Operator
;
2296 ------------------------------------------------
2297 -- Expand_Compare_Minimize_Eliminate_Overflow --
2298 ------------------------------------------------
2300 procedure Expand_Compare_Minimize_Eliminate_Overflow
(N
: Node_Id
) is
2301 Loc
: constant Source_Ptr
:= Sloc
(N
);
2303 Result_Type
: constant Entity_Id
:= Etype
(N
);
2304 -- Capture result type (could be a derived boolean type)
2309 LLIB
: constant Entity_Id
:= Base_Type
(Standard_Long_Long_Integer
);
2310 -- Entity for Long_Long_Integer'Base
2312 Check
: constant Overflow_Mode_Type
:= Overflow_Check_Mode
;
2313 -- Current overflow checking mode
2316 procedure Set_False
;
2317 -- These procedures rewrite N with an occurrence of Standard_True or
2318 -- Standard_False, and then makes a call to Warn_On_Known_Condition.
2324 procedure Set_False
is
2326 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
2327 Warn_On_Known_Condition
(N
);
2334 procedure Set_True
is
2336 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
2337 Warn_On_Known_Condition
(N
);
2340 -- Start of processing for Expand_Compare_Minimize_Eliminate_Overflow
2343 -- Nothing to do unless we have a comparison operator with operands
2344 -- that are signed integer types, and we are operating in either
2345 -- MINIMIZED or ELIMINATED overflow checking mode.
2347 if Nkind
(N
) not in N_Op_Compare
2348 or else Check
not in Minimized_Or_Eliminated
2349 or else not Is_Signed_Integer_Type
(Etype
(Left_Opnd
(N
)))
2354 -- OK, this is the case we are interested in. First step is to process
2355 -- our operands using the Minimize_Eliminate circuitry which applies
2356 -- this processing to the two operand subtrees.
2358 Minimize_Eliminate_Overflows
2359 (Left_Opnd
(N
), Llo
, Lhi
, Top_Level
=> False);
2360 Minimize_Eliminate_Overflows
2361 (Right_Opnd
(N
), Rlo
, Rhi
, Top_Level
=> False);
2363 -- See if the range information decides the result of the comparison.
2364 -- We can only do this if we in fact have full range information (which
2365 -- won't be the case if either operand is bignum at this stage).
2367 if Llo
/= No_Uint
and then Rlo
/= No_Uint
then
2368 case N_Op_Compare
(Nkind
(N
)) is
2370 if Llo
= Lhi
and then Rlo
= Rhi
and then Llo
= Rlo
then
2372 elsif Llo
> Rhi
or else Lhi
< Rlo
then
2379 elsif Lhi
< Rlo
then
2386 elsif Lhi
<= Rlo
then
2393 elsif Lhi
<= Rlo
then
2400 elsif Lhi
< Rlo
then
2405 if Llo
= Lhi
and then Rlo
= Rhi
and then Llo
= Rlo
then
2407 elsif Llo
> Rhi
or else Lhi
< Rlo
then
2412 -- All done if we did the rewrite
2414 if Nkind
(N
) not in N_Op_Compare
then
2419 -- Otherwise, time to do the comparison
2422 Ltype
: constant Entity_Id
:= Etype
(Left_Opnd
(N
));
2423 Rtype
: constant Entity_Id
:= Etype
(Right_Opnd
(N
));
2426 -- If the two operands have the same signed integer type we are
2427 -- all set, nothing more to do. This is the case where either
2428 -- both operands were unchanged, or we rewrote both of them to
2429 -- be Long_Long_Integer.
2431 -- Note: Entity for the comparison may be wrong, but it's not worth
2432 -- the effort to change it, since the back end does not use it.
2434 if Is_Signed_Integer_Type
(Ltype
)
2435 and then Base_Type
(Ltype
) = Base_Type
(Rtype
)
2439 -- Here if bignums are involved (can only happen in ELIMINATED mode)
2441 elsif Is_RTE
(Ltype
, RE_Bignum
) or else Is_RTE
(Rtype
, RE_Bignum
) then
2443 Left
: Node_Id
:= Left_Opnd
(N
);
2444 Right
: Node_Id
:= Right_Opnd
(N
);
2445 -- Bignum references for left and right operands
2448 if not Is_RTE
(Ltype
, RE_Bignum
) then
2449 Left
:= Convert_To_Bignum
(Left
);
2450 elsif not Is_RTE
(Rtype
, RE_Bignum
) then
2451 Right
:= Convert_To_Bignum
(Right
);
2454 -- We rewrite our node with:
2457 -- Bnn : Result_Type;
2459 -- M : Mark_Id := SS_Mark;
2461 -- Bnn := Big_xx (Left, Right); (xx = EQ, NT etc)
2469 Blk
: constant Node_Id
:= Make_Bignum_Block
(Loc
);
2470 Bnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'B', N
);
2474 case N_Op_Compare
(Nkind
(N
)) is
2475 when N_Op_Eq
=> Ent
:= RE_Big_EQ
;
2476 when N_Op_Ge
=> Ent
:= RE_Big_GE
;
2477 when N_Op_Gt
=> Ent
:= RE_Big_GT
;
2478 when N_Op_Le
=> Ent
:= RE_Big_LE
;
2479 when N_Op_Lt
=> Ent
:= RE_Big_LT
;
2480 when N_Op_Ne
=> Ent
:= RE_Big_NE
;
2483 -- Insert assignment to Bnn into the bignum block
2486 (First
(Statements
(Handled_Statement_Sequence
(Blk
))),
2487 Make_Assignment_Statement
(Loc
,
2488 Name
=> New_Occurrence_Of
(Bnn
, Loc
),
2490 Make_Function_Call
(Loc
,
2492 New_Occurrence_Of
(RTE
(Ent
), Loc
),
2493 Parameter_Associations
=> New_List
(Left
, Right
))));
2495 -- Now do the rewrite with expression actions
2498 Make_Expression_With_Actions
(Loc
,
2499 Actions
=> New_List
(
2500 Make_Object_Declaration
(Loc
,
2501 Defining_Identifier
=> Bnn
,
2502 Object_Definition
=>
2503 New_Occurrence_Of
(Result_Type
, Loc
)),
2505 Expression
=> New_Occurrence_Of
(Bnn
, Loc
)));
2506 Analyze_And_Resolve
(N
, Result_Type
);
2510 -- No bignums involved, but types are different, so we must have
2511 -- rewritten one of the operands as a Long_Long_Integer but not
2514 -- If left operand is Long_Long_Integer, convert right operand
2515 -- and we are done (with a comparison of two Long_Long_Integers).
2517 elsif Ltype
= LLIB
then
2518 Convert_To_And_Rewrite
(LLIB
, Right_Opnd
(N
));
2519 Analyze_And_Resolve
(Right_Opnd
(N
), LLIB
, Suppress
=> All_Checks
);
2522 -- If right operand is Long_Long_Integer, convert left operand
2523 -- and we are done (with a comparison of two Long_Long_Integers).
2525 -- This is the only remaining possibility
2527 else pragma Assert
(Rtype
= LLIB
);
2528 Convert_To_And_Rewrite
(LLIB
, Left_Opnd
(N
));
2529 Analyze_And_Resolve
(Left_Opnd
(N
), LLIB
, Suppress
=> All_Checks
);
2533 end Expand_Compare_Minimize_Eliminate_Overflow
;
2535 -------------------------------
2536 -- Expand_Composite_Equality --
2537 -------------------------------
2539 -- This function is only called for comparing internal fields of composite
2540 -- types when these fields are themselves composites. This is a special
2541 -- case because it is not possible to respect normal Ada visibility rules.
2543 function Expand_Composite_Equality
2548 Bodies
: List_Id
) return Node_Id
2550 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
2551 Full_Type
: Entity_Id
;
2555 function Find_Primitive_Eq
return Node_Id
;
2556 -- AI05-0123: Locate primitive equality for type if it exists, and
2557 -- build the corresponding call. If operation is abstract, replace
2558 -- call with an explicit raise. Return Empty if there is no primitive.
2560 -----------------------
2561 -- Find_Primitive_Eq --
2562 -----------------------
2564 function Find_Primitive_Eq
return Node_Id
is
2569 Prim_E
:= First_Elmt
(Collect_Primitive_Operations
(Typ
));
2570 while Present
(Prim_E
) loop
2571 Prim
:= Node
(Prim_E
);
2573 -- Locate primitive equality with the right signature
2575 if Chars
(Prim
) = Name_Op_Eq
2576 and then Etype
(First_Formal
(Prim
)) =
2577 Etype
(Next_Formal
(First_Formal
(Prim
)))
2578 and then Etype
(Prim
) = Standard_Boolean
2580 if Is_Abstract_Subprogram
(Prim
) then
2582 Make_Raise_Program_Error
(Loc
,
2583 Reason
=> PE_Explicit_Raise
);
2587 Make_Function_Call
(Loc
,
2588 Name
=> New_Occurrence_Of
(Prim
, Loc
),
2589 Parameter_Associations
=> New_List
(Lhs
, Rhs
));
2596 -- If not found, predefined operation will be used
2599 end Find_Primitive_Eq
;
2601 -- Start of processing for Expand_Composite_Equality
2604 if Is_Private_Type
(Typ
) then
2605 Full_Type
:= Underlying_Type
(Typ
);
2610 -- If the private type has no completion the context may be the
2611 -- expansion of a composite equality for a composite type with some
2612 -- still incomplete components. The expression will not be analyzed
2613 -- until the enclosing type is completed, at which point this will be
2614 -- properly expanded, unless there is a bona fide completion error.
2616 if No
(Full_Type
) then
2617 return Make_Op_Eq
(Loc
, Left_Opnd
=> Lhs
, Right_Opnd
=> Rhs
);
2620 Full_Type
:= Base_Type
(Full_Type
);
2622 -- When the base type itself is private, use the full view to expand
2623 -- the composite equality.
2625 if Is_Private_Type
(Full_Type
) then
2626 Full_Type
:= Underlying_Type
(Full_Type
);
2629 -- Case of array types
2631 if Is_Array_Type
(Full_Type
) then
2633 -- If the operand is an elementary type other than a floating-point
2634 -- type, then we can simply use the built-in block bitwise equality,
2635 -- since the predefined equality operators always apply and bitwise
2636 -- equality is fine for all these cases.
2638 if Is_Elementary_Type
(Component_Type
(Full_Type
))
2639 and then not Is_Floating_Point_Type
(Component_Type
(Full_Type
))
2641 return Make_Op_Eq
(Loc
, Left_Opnd
=> Lhs
, Right_Opnd
=> Rhs
);
2643 -- For composite component types, and floating-point types, use the
2644 -- expansion. This deals with tagged component types (where we use
2645 -- the applicable equality routine) and floating-point, (where we
2646 -- need to worry about negative zeroes), and also the case of any
2647 -- composite type recursively containing such fields.
2650 return Expand_Array_Equality
(Nod
, Lhs
, Rhs
, Bodies
, Full_Type
);
2653 -- Case of tagged record types
2655 elsif Is_Tagged_Type
(Full_Type
) then
2657 -- Call the primitive operation "=" of this type
2659 if Is_Class_Wide_Type
(Full_Type
) then
2660 Full_Type
:= Root_Type
(Full_Type
);
2663 -- If this is derived from an untagged private type completed with a
2664 -- tagged type, it does not have a full view, so we use the primitive
2665 -- operations of the private type. This check should no longer be
2666 -- necessary when these types receive their full views ???
2668 if Is_Private_Type
(Typ
)
2669 and then not Is_Tagged_Type
(Typ
)
2670 and then not Is_Controlled
(Typ
)
2671 and then Is_Derived_Type
(Typ
)
2672 and then No
(Full_View
(Typ
))
2674 Prim
:= First_Elmt
(Collect_Primitive_Operations
(Typ
));
2676 Prim
:= First_Elmt
(Primitive_Operations
(Full_Type
));
2680 Eq_Op
:= Node
(Prim
);
2681 exit when Chars
(Eq_Op
) = Name_Op_Eq
2682 and then Etype
(First_Formal
(Eq_Op
)) =
2683 Etype
(Next_Formal
(First_Formal
(Eq_Op
)))
2684 and then Base_Type
(Etype
(Eq_Op
)) = Standard_Boolean
;
2686 pragma Assert
(Present
(Prim
));
2689 Eq_Op
:= Node
(Prim
);
2692 Make_Function_Call
(Loc
,
2693 Name
=> New_Occurrence_Of
(Eq_Op
, Loc
),
2694 Parameter_Associations
=>
2696 (Unchecked_Convert_To
(Etype
(First_Formal
(Eq_Op
)), Lhs
),
2697 Unchecked_Convert_To
(Etype
(First_Formal
(Eq_Op
)), Rhs
)));
2699 -- Case of untagged record types
2701 elsif Is_Record_Type
(Full_Type
) then
2702 Eq_Op
:= TSS
(Full_Type
, TSS_Composite_Equality
);
2704 if Present
(Eq_Op
) then
2705 if Etype
(First_Formal
(Eq_Op
)) /= Full_Type
then
2707 -- Inherited equality from parent type. Convert the actuals to
2708 -- match signature of operation.
2711 T
: constant Entity_Id
:= Etype
(First_Formal
(Eq_Op
));
2715 Make_Function_Call
(Loc
,
2716 Name
=> New_Occurrence_Of
(Eq_Op
, Loc
),
2717 Parameter_Associations
=> New_List
(
2718 OK_Convert_To
(T
, Lhs
),
2719 OK_Convert_To
(T
, Rhs
)));
2723 -- Comparison between Unchecked_Union components
2725 if Is_Unchecked_Union
(Full_Type
) then
2727 Lhs_Type
: Node_Id
:= Full_Type
;
2728 Rhs_Type
: Node_Id
:= Full_Type
;
2729 Lhs_Discr_Val
: Node_Id
;
2730 Rhs_Discr_Val
: Node_Id
;
2735 if Nkind
(Lhs
) = N_Selected_Component
then
2736 Lhs_Type
:= Etype
(Entity
(Selector_Name
(Lhs
)));
2741 if Nkind
(Rhs
) = N_Selected_Component
then
2742 Rhs_Type
:= Etype
(Entity
(Selector_Name
(Rhs
)));
2745 -- Lhs of the composite equality
2747 if Is_Constrained
(Lhs_Type
) then
2749 -- Since the enclosing record type can never be an
2750 -- Unchecked_Union (this code is executed for records
2751 -- that do not have variants), we may reference its
2754 if Nkind
(Lhs
) = N_Selected_Component
2755 and then Has_Per_Object_Constraint
2756 (Entity
(Selector_Name
(Lhs
)))
2759 Make_Selected_Component
(Loc
,
2760 Prefix
=> Prefix
(Lhs
),
2763 (Get_Discriminant_Value
2764 (First_Discriminant
(Lhs_Type
),
2766 Stored_Constraint
(Lhs_Type
))));
2771 (Get_Discriminant_Value
2772 (First_Discriminant
(Lhs_Type
),
2774 Stored_Constraint
(Lhs_Type
)));
2778 -- It is not possible to infer the discriminant since
2779 -- the subtype is not constrained.
2782 Make_Raise_Program_Error
(Loc
,
2783 Reason
=> PE_Unchecked_Union_Restriction
);
2786 -- Rhs of the composite equality
2788 if Is_Constrained
(Rhs_Type
) then
2789 if Nkind
(Rhs
) = N_Selected_Component
2790 and then Has_Per_Object_Constraint
2791 (Entity
(Selector_Name
(Rhs
)))
2794 Make_Selected_Component
(Loc
,
2795 Prefix
=> Prefix
(Rhs
),
2798 (Get_Discriminant_Value
2799 (First_Discriminant
(Rhs_Type
),
2801 Stored_Constraint
(Rhs_Type
))));
2806 (Get_Discriminant_Value
2807 (First_Discriminant
(Rhs_Type
),
2809 Stored_Constraint
(Rhs_Type
)));
2814 Make_Raise_Program_Error
(Loc
,
2815 Reason
=> PE_Unchecked_Union_Restriction
);
2818 -- Call the TSS equality function with the inferred
2819 -- discriminant values.
2822 Make_Function_Call
(Loc
,
2823 Name
=> New_Occurrence_Of
(Eq_Op
, Loc
),
2824 Parameter_Associations
=> New_List
(
2831 -- All cases other than comparing Unchecked_Union types
2835 T
: constant Entity_Id
:= Etype
(First_Formal
(Eq_Op
));
2838 Make_Function_Call
(Loc
,
2840 New_Occurrence_Of
(Eq_Op
, Loc
),
2841 Parameter_Associations
=> New_List
(
2842 OK_Convert_To
(T
, Lhs
),
2843 OK_Convert_To
(T
, Rhs
)));
2848 -- Equality composes in Ada 2012 for untagged record types. It also
2849 -- composes for bounded strings, because they are part of the
2850 -- predefined environment. We could make it compose for bounded
2851 -- strings by making them tagged, or by making sure all subcomponents
2852 -- are set to the same value, even when not used. Instead, we have
2853 -- this special case in the compiler, because it's more efficient.
2855 elsif Ada_Version
>= Ada_2012
or else Is_Bounded_String
(Typ
) then
2857 -- If no TSS has been created for the type, check whether there is
2858 -- a primitive equality declared for it.
2861 Op
: constant Node_Id
:= Find_Primitive_Eq
;
2864 -- Use user-defined primitive if it exists, otherwise use
2865 -- predefined equality.
2867 if Present
(Op
) then
2870 return Make_Op_Eq
(Loc
, Lhs
, Rhs
);
2875 return Expand_Record_Equality
(Nod
, Full_Type
, Lhs
, Rhs
, Bodies
);
2878 -- Non-composite types (always use predefined equality)
2881 return Make_Op_Eq
(Loc
, Left_Opnd
=> Lhs
, Right_Opnd
=> Rhs
);
2883 end Expand_Composite_Equality
;
2885 ------------------------
2886 -- Expand_Concatenate --
2887 ------------------------
2889 procedure Expand_Concatenate
(Cnode
: Node_Id
; Opnds
: List_Id
) is
2890 Loc
: constant Source_Ptr
:= Sloc
(Cnode
);
2892 Atyp
: constant Entity_Id
:= Base_Type
(Etype
(Cnode
));
2893 -- Result type of concatenation
2895 Ctyp
: constant Entity_Id
:= Base_Type
(Component_Type
(Etype
(Cnode
)));
2896 -- Component type. Elements of this component type can appear as one
2897 -- of the operands of concatenation as well as arrays.
2899 Istyp
: constant Entity_Id
:= Etype
(First_Index
(Atyp
));
2902 Ityp
: constant Entity_Id
:= Base_Type
(Istyp
);
2903 -- Index type. This is the base type of the index subtype, and is used
2904 -- for all computed bounds (which may be out of range of Istyp in the
2905 -- case of null ranges).
2908 -- This is the type we use to do arithmetic to compute the bounds and
2909 -- lengths of operands. The choice of this type is a little subtle and
2910 -- is discussed in a separate section at the start of the body code.
2912 Concatenation_Error
: exception;
2913 -- Raised if concatenation is sure to raise a CE
2915 Result_May_Be_Null
: Boolean := True;
2916 -- Reset to False if at least one operand is encountered which is known
2917 -- at compile time to be non-null. Used for handling the special case
2918 -- of setting the high bound to the last operand high bound for a null
2919 -- result, thus ensuring a proper high bound in the super-flat case.
2921 N
: constant Nat
:= List_Length
(Opnds
);
2922 -- Number of concatenation operands including possibly null operands
2925 -- Number of operands excluding any known to be null, except that the
2926 -- last operand is always retained, in case it provides the bounds for
2930 -- Current operand being processed in the loop through operands. After
2931 -- this loop is complete, always contains the last operand (which is not
2932 -- the same as Operands (NN), since null operands are skipped).
2934 -- Arrays describing the operands, only the first NN entries of each
2935 -- array are set (NN < N when we exclude known null operands).
2937 Is_Fixed_Length
: array (1 .. N
) of Boolean;
2938 -- True if length of corresponding operand known at compile time
2940 Operands
: array (1 .. N
) of Node_Id
;
2941 -- Set to the corresponding entry in the Opnds list (but note that null
2942 -- operands are excluded, so not all entries in the list are stored).
2944 Fixed_Length
: array (1 .. N
) of Uint
;
2945 -- Set to length of operand. Entries in this array are set only if the
2946 -- corresponding entry in Is_Fixed_Length is True.
2948 Opnd_Low_Bound
: array (1 .. N
) of Node_Id
;
2949 -- Set to lower bound of operand. Either an integer literal in the case
2950 -- where the bound is known at compile time, else actual lower bound.
2951 -- The operand low bound is of type Ityp.
2953 Var_Length
: array (1 .. N
) of Entity_Id
;
2954 -- Set to an entity of type Natural that contains the length of an
2955 -- operand whose length is not known at compile time. Entries in this
2956 -- array are set only if the corresponding entry in Is_Fixed_Length
2957 -- is False. The entity is of type Artyp.
2959 Aggr_Length
: array (0 .. N
) of Node_Id
;
2960 -- The J'th entry in an expression node that represents the total length
2961 -- of operands 1 through J. It is either an integer literal node, or a
2962 -- reference to a constant entity with the right value, so it is fine
2963 -- to just do a Copy_Node to get an appropriate copy. The extra zero'th
2964 -- entry always is set to zero. The length is of type Artyp.
2966 Low_Bound
: Node_Id
;
2967 -- A tree node representing the low bound of the result (of type Ityp).
2968 -- This is either an integer literal node, or an identifier reference to
2969 -- a constant entity initialized to the appropriate value.
2971 Last_Opnd_Low_Bound
: Node_Id
;
2972 -- A tree node representing the low bound of the last operand. This
2973 -- need only be set if the result could be null. It is used for the
2974 -- special case of setting the right low bound for a null result.
2975 -- This is of type Ityp.
2977 Last_Opnd_High_Bound
: Node_Id
;
2978 -- A tree node representing the high bound of the last operand. This
2979 -- need only be set if the result could be null. It is used for the
2980 -- special case of setting the right high bound for a null result.
2981 -- This is of type Ityp.
2983 High_Bound
: Node_Id
;
2984 -- A tree node representing the high bound of the result (of type Ityp)
2987 -- Result of the concatenation (of type Ityp)
2989 Actions
: constant List_Id
:= New_List
;
2990 -- Collect actions to be inserted
2992 Known_Non_Null_Operand_Seen
: Boolean;
2993 -- Set True during generation of the assignments of operands into
2994 -- result once an operand known to be non-null has been seen.
2996 function Make_Artyp_Literal
(Val
: Nat
) return Node_Id
;
2997 -- This function makes an N_Integer_Literal node that is returned in
2998 -- analyzed form with the type set to Artyp. Importantly this literal
2999 -- is not flagged as static, so that if we do computations with it that
3000 -- result in statically detected out of range conditions, we will not
3001 -- generate error messages but instead warning messages.
3003 function To_Artyp
(X
: Node_Id
) return Node_Id
;
3004 -- Given a node of type Ityp, returns the corresponding value of type
3005 -- Artyp. For non-enumeration types, this is a plain integer conversion.
3006 -- For enum types, the Pos of the value is returned.
3008 function To_Ityp
(X
: Node_Id
) return Node_Id
;
3009 -- The inverse function (uses Val in the case of enumeration types)
3011 ------------------------
3012 -- Make_Artyp_Literal --
3013 ------------------------
3015 function Make_Artyp_Literal
(Val
: Nat
) return Node_Id
is
3016 Result
: constant Node_Id
:= Make_Integer_Literal
(Loc
, Val
);
3018 Set_Etype
(Result
, Artyp
);
3019 Set_Analyzed
(Result
, True);
3020 Set_Is_Static_Expression
(Result
, False);
3022 end Make_Artyp_Literal
;
3028 function To_Artyp
(X
: Node_Id
) return Node_Id
is
3030 if Ityp
= Base_Type
(Artyp
) then
3033 elsif Is_Enumeration_Type
(Ityp
) then
3035 Make_Attribute_Reference
(Loc
,
3036 Prefix
=> New_Occurrence_Of
(Ityp
, Loc
),
3037 Attribute_Name
=> Name_Pos
,
3038 Expressions
=> New_List
(X
));
3041 return Convert_To
(Artyp
, X
);
3049 function To_Ityp
(X
: Node_Id
) return Node_Id
is
3051 if Is_Enumeration_Type
(Ityp
) then
3053 Make_Attribute_Reference
(Loc
,
3054 Prefix
=> New_Occurrence_Of
(Ityp
, Loc
),
3055 Attribute_Name
=> Name_Val
,
3056 Expressions
=> New_List
(X
));
3058 -- Case where we will do a type conversion
3061 if Ityp
= Base_Type
(Artyp
) then
3064 return Convert_To
(Ityp
, X
);
3069 -- Local Declarations
3071 Lib_Level_Target
: constant Boolean :=
3072 Nkind
(Parent
(Cnode
)) = N_Object_Declaration
3074 Is_Library_Level_Entity
(Defining_Identifier
(Parent
(Cnode
)));
3076 -- If the concatenation declares a library level entity, we call the
3077 -- built-in concatenation routines to prevent code bloat, regardless
3078 -- of optimization level. This is space-efficient, and prevent linking
3079 -- problems when units are compiled with different optimizations.
3081 Opnd_Typ
: Entity_Id
;
3088 -- Start of processing for Expand_Concatenate
3091 -- Choose an appropriate computational type
3093 -- We will be doing calculations of lengths and bounds in this routine
3094 -- and computing one from the other in some cases, e.g. getting the high
3095 -- bound by adding the length-1 to the low bound.
3097 -- We can't just use the index type, or even its base type for this
3098 -- purpose for two reasons. First it might be an enumeration type which
3099 -- is not suitable for computations of any kind, and second it may
3100 -- simply not have enough range. For example if the index type is
3101 -- -128..+127 then lengths can be up to 256, which is out of range of
3104 -- For enumeration types, we can simply use Standard_Integer, this is
3105 -- sufficient since the actual number of enumeration literals cannot
3106 -- possibly exceed the range of integer (remember we will be doing the
3107 -- arithmetic with POS values, not representation values).
3109 if Is_Enumeration_Type
(Ityp
) then
3110 Artyp
:= Standard_Integer
;
3112 -- If index type is Positive, we use the standard unsigned type, to give
3113 -- more room on the top of the range, obviating the need for an overflow
3114 -- check when creating the upper bound. This is needed to avoid junk
3115 -- overflow checks in the common case of String types.
3117 -- ??? Disabled for now
3119 -- elsif Istyp = Standard_Positive then
3120 -- Artyp := Standard_Unsigned;
3122 -- For modular types, we use a 32-bit modular type for types whose size
3123 -- is in the range 1-31 bits. For 32-bit unsigned types, we use the
3124 -- identity type, and for larger unsigned types we use 64-bits.
3126 elsif Is_Modular_Integer_Type
(Ityp
) then
3127 if RM_Size
(Ityp
) < RM_Size
(Standard_Unsigned
) then
3128 Artyp
:= Standard_Unsigned
;
3129 elsif RM_Size
(Ityp
) = RM_Size
(Standard_Unsigned
) then
3132 Artyp
:= RTE
(RE_Long_Long_Unsigned
);
3135 -- Similar treatment for signed types
3138 if RM_Size
(Ityp
) < RM_Size
(Standard_Integer
) then
3139 Artyp
:= Standard_Integer
;
3140 elsif RM_Size
(Ityp
) = RM_Size
(Standard_Integer
) then
3143 Artyp
:= Standard_Long_Long_Integer
;
3147 -- Supply dummy entry at start of length array
3149 Aggr_Length
(0) := Make_Artyp_Literal
(0);
3151 -- Go through operands setting up the above arrays
3155 Opnd
:= Remove_Head
(Opnds
);
3156 Opnd_Typ
:= Etype
(Opnd
);
3158 -- The parent got messed up when we put the operands in a list,
3159 -- so now put back the proper parent for the saved operand, that
3160 -- is to say the concatenation node, to make sure that each operand
3161 -- is seen as a subexpression, e.g. if actions must be inserted.
3163 Set_Parent
(Opnd
, Cnode
);
3165 -- Set will be True when we have setup one entry in the array
3169 -- Singleton element (or character literal) case
3171 if Base_Type
(Opnd_Typ
) = Ctyp
then
3173 Operands
(NN
) := Opnd
;
3174 Is_Fixed_Length
(NN
) := True;
3175 Fixed_Length
(NN
) := Uint_1
;
3176 Result_May_Be_Null
:= False;
3178 -- Set low bound of operand (no need to set Last_Opnd_High_Bound
3179 -- since we know that the result cannot be null).
3181 Opnd_Low_Bound
(NN
) :=
3182 Make_Attribute_Reference
(Loc
,
3183 Prefix
=> New_Occurrence_Of
(Istyp
, Loc
),
3184 Attribute_Name
=> Name_First
);
3188 -- String literal case (can only occur for strings of course)
3190 elsif Nkind
(Opnd
) = N_String_Literal
then
3191 Len
:= String_Literal_Length
(Opnd_Typ
);
3194 Result_May_Be_Null
:= False;
3197 -- Capture last operand low and high bound if result could be null
3199 if J
= N
and then Result_May_Be_Null
then
3200 Last_Opnd_Low_Bound
:=
3201 New_Copy_Tree
(String_Literal_Low_Bound
(Opnd_Typ
));
3203 Last_Opnd_High_Bound
:=
3204 Make_Op_Subtract
(Loc
,
3206 New_Copy_Tree
(String_Literal_Low_Bound
(Opnd_Typ
)),
3207 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1));
3210 -- Skip null string literal
3212 if J
< N
and then Len
= 0 then
3217 Operands
(NN
) := Opnd
;
3218 Is_Fixed_Length
(NN
) := True;
3220 -- Set length and bounds
3222 Fixed_Length
(NN
) := Len
;
3224 Opnd_Low_Bound
(NN
) :=
3225 New_Copy_Tree
(String_Literal_Low_Bound
(Opnd_Typ
));
3232 -- Check constrained case with known bounds
3234 if Is_Constrained
(Opnd_Typ
) then
3236 Index
: constant Node_Id
:= First_Index
(Opnd_Typ
);
3237 Indx_Typ
: constant Entity_Id
:= Etype
(Index
);
3238 Lo
: constant Node_Id
:= Type_Low_Bound
(Indx_Typ
);
3239 Hi
: constant Node_Id
:= Type_High_Bound
(Indx_Typ
);
3242 -- Fixed length constrained array type with known at compile
3243 -- time bounds is last case of fixed length operand.
3245 if Compile_Time_Known_Value
(Lo
)
3247 Compile_Time_Known_Value
(Hi
)
3250 Loval
: constant Uint
:= Expr_Value
(Lo
);
3251 Hival
: constant Uint
:= Expr_Value
(Hi
);
3252 Len
: constant Uint
:=
3253 UI_Max
(Hival
- Loval
+ 1, Uint_0
);
3257 Result_May_Be_Null
:= False;
3260 -- Capture last operand bounds if result could be null
3262 if J
= N
and then Result_May_Be_Null
then
3263 Last_Opnd_Low_Bound
:=
3265 Make_Integer_Literal
(Loc
, Expr_Value
(Lo
)));
3267 Last_Opnd_High_Bound
:=
3269 Make_Integer_Literal
(Loc
, Expr_Value
(Hi
)));
3272 -- Exclude null length case unless last operand
3274 if J
< N
and then Len
= 0 then
3279 Operands
(NN
) := Opnd
;
3280 Is_Fixed_Length
(NN
) := True;
3281 Fixed_Length
(NN
) := Len
;
3283 Opnd_Low_Bound
(NN
) :=
3285 (Make_Integer_Literal
(Loc
, Expr_Value
(Lo
)));
3292 -- All cases where the length is not known at compile time, or the
3293 -- special case of an operand which is known to be null but has a
3294 -- lower bound other than 1 or is other than a string type.
3299 -- Capture operand bounds
3301 Opnd_Low_Bound
(NN
) :=
3302 Make_Attribute_Reference
(Loc
,
3304 Duplicate_Subexpr
(Opnd
, Name_Req
=> True),
3305 Attribute_Name
=> Name_First
);
3307 -- Capture last operand bounds if result could be null
3309 if J
= N
and Result_May_Be_Null
then
3310 Last_Opnd_Low_Bound
:=
3312 Make_Attribute_Reference
(Loc
,
3314 Duplicate_Subexpr
(Opnd
, Name_Req
=> True),
3315 Attribute_Name
=> Name_First
));
3317 Last_Opnd_High_Bound
:=
3319 Make_Attribute_Reference
(Loc
,
3321 Duplicate_Subexpr
(Opnd
, Name_Req
=> True),
3322 Attribute_Name
=> Name_Last
));
3325 -- Capture length of operand in entity
3327 Operands
(NN
) := Opnd
;
3328 Is_Fixed_Length
(NN
) := False;
3330 Var_Length
(NN
) := Make_Temporary
(Loc
, 'L');
3333 Make_Object_Declaration
(Loc
,
3334 Defining_Identifier
=> Var_Length
(NN
),
3335 Constant_Present
=> True,
3336 Object_Definition
=> New_Occurrence_Of
(Artyp
, Loc
),
3338 Make_Attribute_Reference
(Loc
,
3340 Duplicate_Subexpr
(Opnd
, Name_Req
=> True),
3341 Attribute_Name
=> Name_Length
)));
3345 -- Set next entry in aggregate length array
3347 -- For first entry, make either integer literal for fixed length
3348 -- or a reference to the saved length for variable length.
3351 if Is_Fixed_Length
(1) then
3352 Aggr_Length
(1) := Make_Integer_Literal
(Loc
, Fixed_Length
(1));
3354 Aggr_Length
(1) := New_Occurrence_Of
(Var_Length
(1), Loc
);
3357 -- If entry is fixed length and only fixed lengths so far, make
3358 -- appropriate new integer literal adding new length.
3360 elsif Is_Fixed_Length
(NN
)
3361 and then Nkind
(Aggr_Length
(NN
- 1)) = N_Integer_Literal
3364 Make_Integer_Literal
(Loc
,
3365 Intval
=> Fixed_Length
(NN
) + Intval
(Aggr_Length
(NN
- 1)));
3367 -- All other cases, construct an addition node for the length and
3368 -- create an entity initialized to this length.
3371 Ent
:= Make_Temporary
(Loc
, 'L');
3373 if Is_Fixed_Length
(NN
) then
3374 Clen
:= Make_Integer_Literal
(Loc
, Fixed_Length
(NN
));
3376 Clen
:= New_Occurrence_Of
(Var_Length
(NN
), Loc
);
3380 Make_Object_Declaration
(Loc
,
3381 Defining_Identifier
=> Ent
,
3382 Constant_Present
=> True,
3383 Object_Definition
=> New_Occurrence_Of
(Artyp
, Loc
),
3386 Left_Opnd
=> New_Copy
(Aggr_Length
(NN
- 1)),
3387 Right_Opnd
=> Clen
)));
3389 Aggr_Length
(NN
) := Make_Identifier
(Loc
, Chars
=> Chars
(Ent
));
3396 -- If we have only skipped null operands, return the last operand
3403 -- If we have only one non-null operand, return it and we are done.
3404 -- There is one case in which this cannot be done, and that is when
3405 -- the sole operand is of the element type, in which case it must be
3406 -- converted to an array, and the easiest way of doing that is to go
3407 -- through the normal general circuit.
3409 if NN
= 1 and then Base_Type
(Etype
(Operands
(1))) /= Ctyp
then
3410 Result
:= Operands
(1);
3414 -- Cases where we have a real concatenation
3416 -- Next step is to find the low bound for the result array that we
3417 -- will allocate. The rules for this are in (RM 4.5.6(5-7)).
3419 -- If the ultimate ancestor of the index subtype is a constrained array
3420 -- definition, then the lower bound is that of the index subtype as
3421 -- specified by (RM 4.5.3(6)).
3423 -- The right test here is to go to the root type, and then the ultimate
3424 -- ancestor is the first subtype of this root type.
3426 if Is_Constrained
(First_Subtype
(Root_Type
(Atyp
))) then
3428 Make_Attribute_Reference
(Loc
,
3430 New_Occurrence_Of
(First_Subtype
(Root_Type
(Atyp
)), Loc
),
3431 Attribute_Name
=> Name_First
);
3433 -- If the first operand in the list has known length we know that
3434 -- the lower bound of the result is the lower bound of this operand.
3436 elsif Is_Fixed_Length
(1) then
3437 Low_Bound
:= Opnd_Low_Bound
(1);
3439 -- OK, we don't know the lower bound, we have to build a horrible
3440 -- if expression node of the form
3442 -- if Cond1'Length /= 0 then
3445 -- if Opnd2'Length /= 0 then
3450 -- The nesting ends either when we hit an operand whose length is known
3451 -- at compile time, or on reaching the last operand, whose low bound we
3452 -- take unconditionally whether or not it is null. It's easiest to do
3453 -- this with a recursive procedure:
3457 function Get_Known_Bound
(J
: Nat
) return Node_Id
;
3458 -- Returns the lower bound determined by operands J .. NN
3460 ---------------------
3461 -- Get_Known_Bound --
3462 ---------------------
3464 function Get_Known_Bound
(J
: Nat
) return Node_Id
is
3466 if Is_Fixed_Length
(J
) or else J
= NN
then
3467 return New_Copy
(Opnd_Low_Bound
(J
));
3471 Make_If_Expression
(Loc
,
3472 Expressions
=> New_List
(
3476 New_Occurrence_Of
(Var_Length
(J
), Loc
),
3478 Make_Integer_Literal
(Loc
, 0)),
3480 New_Copy
(Opnd_Low_Bound
(J
)),
3481 Get_Known_Bound
(J
+ 1)));
3483 end Get_Known_Bound
;
3486 Ent
:= Make_Temporary
(Loc
, 'L');
3489 Make_Object_Declaration
(Loc
,
3490 Defining_Identifier
=> Ent
,
3491 Constant_Present
=> True,
3492 Object_Definition
=> New_Occurrence_Of
(Ityp
, Loc
),
3493 Expression
=> Get_Known_Bound
(1)));
3495 Low_Bound
:= New_Occurrence_Of
(Ent
, Loc
);
3499 -- Now we can safely compute the upper bound, normally
3500 -- Low_Bound + Length - 1.
3505 Left_Opnd
=> To_Artyp
(New_Copy
(Low_Bound
)),
3507 Make_Op_Subtract
(Loc
,
3508 Left_Opnd
=> New_Copy
(Aggr_Length
(NN
)),
3509 Right_Opnd
=> Make_Artyp_Literal
(1))));
3511 -- Note that calculation of the high bound may cause overflow in some
3512 -- very weird cases, so in the general case we need an overflow check on
3513 -- the high bound. We can avoid this for the common case of string types
3514 -- and other types whose index is Positive, since we chose a wider range
3515 -- for the arithmetic type.
3517 if Istyp
/= Standard_Positive
then
3518 Activate_Overflow_Check
(High_Bound
);
3521 -- Handle the exceptional case where the result is null, in which case
3522 -- case the bounds come from the last operand (so that we get the proper
3523 -- bounds if the last operand is super-flat).
3525 if Result_May_Be_Null
then
3527 Make_If_Expression
(Loc
,
3528 Expressions
=> New_List
(
3530 Left_Opnd
=> New_Copy
(Aggr_Length
(NN
)),
3531 Right_Opnd
=> Make_Artyp_Literal
(0)),
3532 Last_Opnd_Low_Bound
,
3536 Make_If_Expression
(Loc
,
3537 Expressions
=> New_List
(
3539 Left_Opnd
=> New_Copy
(Aggr_Length
(NN
)),
3540 Right_Opnd
=> Make_Artyp_Literal
(0)),
3541 Last_Opnd_High_Bound
,
3545 -- Here is where we insert the saved up actions
3547 Insert_Actions
(Cnode
, Actions
, Suppress
=> All_Checks
);
3549 -- Now we construct an array object with appropriate bounds. We mark
3550 -- the target as internal to prevent useless initialization when
3551 -- Initialize_Scalars is enabled. Also since this is the actual result
3552 -- entity, we make sure we have debug information for the result.
3554 Ent
:= Make_Temporary
(Loc
, 'S');
3555 Set_Is_Internal
(Ent
);
3556 Set_Needs_Debug_Info
(Ent
);
3558 -- If the bound is statically known to be out of range, we do not want
3559 -- to abort, we want a warning and a runtime constraint error. Note that
3560 -- we have arranged that the result will not be treated as a static
3561 -- constant, so we won't get an illegality during this insertion.
3563 Insert_Action
(Cnode
,
3564 Make_Object_Declaration
(Loc
,
3565 Defining_Identifier
=> Ent
,
3566 Object_Definition
=>
3567 Make_Subtype_Indication
(Loc
,
3568 Subtype_Mark
=> New_Occurrence_Of
(Atyp
, Loc
),
3570 Make_Index_Or_Discriminant_Constraint
(Loc
,
3571 Constraints
=> New_List
(
3573 Low_Bound
=> Low_Bound
,
3574 High_Bound
=> High_Bound
))))),
3575 Suppress
=> All_Checks
);
3577 -- If the result of the concatenation appears as the initializing
3578 -- expression of an object declaration, we can just rename the
3579 -- result, rather than copying it.
3581 Set_OK_To_Rename
(Ent
);
3583 -- Catch the static out of range case now
3585 if Raises_Constraint_Error
(High_Bound
) then
3586 raise Concatenation_Error
;
3589 -- Now we will generate the assignments to do the actual concatenation
3591 -- There is one case in which we will not do this, namely when all the
3592 -- following conditions are met:
3594 -- The result type is Standard.String
3596 -- There are nine or fewer retained (non-null) operands
3598 -- The optimization level is -O0
3600 -- The corresponding System.Concat_n.Str_Concat_n routine is
3601 -- available in the run time.
3603 -- The debug flag gnatd.c is not set
3605 -- If all these conditions are met then we generate a call to the
3606 -- relevant concatenation routine. The purpose of this is to avoid
3607 -- undesirable code bloat at -O0.
3609 if Atyp
= Standard_String
3610 and then NN
in 2 .. 9
3611 and then (Lib_Level_Target
3612 or else ((Opt
.Optimization_Level
= 0 or else Debug_Flag_Dot_CC
)
3613 and then not Debug_Flag_Dot_C
))
3616 RR
: constant array (Nat
range 2 .. 9) of RE_Id
:=
3627 if RTE_Available
(RR
(NN
)) then
3629 Opnds
: constant List_Id
:=
3630 New_List
(New_Occurrence_Of
(Ent
, Loc
));
3633 for J
in 1 .. NN
loop
3634 if Is_List_Member
(Operands
(J
)) then
3635 Remove
(Operands
(J
));
3638 if Base_Type
(Etype
(Operands
(J
))) = Ctyp
then
3640 Make_Aggregate
(Loc
,
3641 Component_Associations
=> New_List
(
3642 Make_Component_Association
(Loc
,
3643 Choices
=> New_List
(
3644 Make_Integer_Literal
(Loc
, 1)),
3645 Expression
=> Operands
(J
)))));
3648 Append_To
(Opnds
, Operands
(J
));
3652 Insert_Action
(Cnode
,
3653 Make_Procedure_Call_Statement
(Loc
,
3654 Name
=> New_Occurrence_Of
(RTE
(RR
(NN
)), Loc
),
3655 Parameter_Associations
=> Opnds
));
3657 Result
:= New_Occurrence_Of
(Ent
, Loc
);
3664 -- Not special case so generate the assignments
3666 Known_Non_Null_Operand_Seen
:= False;
3668 for J
in 1 .. NN
loop
3670 Lo
: constant Node_Id
:=
3672 Left_Opnd
=> To_Artyp
(New_Copy
(Low_Bound
)),
3673 Right_Opnd
=> Aggr_Length
(J
- 1));
3675 Hi
: constant Node_Id
:=
3677 Left_Opnd
=> To_Artyp
(New_Copy
(Low_Bound
)),
3679 Make_Op_Subtract
(Loc
,
3680 Left_Opnd
=> Aggr_Length
(J
),
3681 Right_Opnd
=> Make_Artyp_Literal
(1)));
3684 -- Singleton case, simple assignment
3686 if Base_Type
(Etype
(Operands
(J
))) = Ctyp
then
3687 Known_Non_Null_Operand_Seen
:= True;
3688 Insert_Action
(Cnode
,
3689 Make_Assignment_Statement
(Loc
,
3691 Make_Indexed_Component
(Loc
,
3692 Prefix
=> New_Occurrence_Of
(Ent
, Loc
),
3693 Expressions
=> New_List
(To_Ityp
(Lo
))),
3694 Expression
=> Operands
(J
)),
3695 Suppress
=> All_Checks
);
3697 -- Array case, slice assignment, skipped when argument is fixed
3698 -- length and known to be null.
3700 elsif (not Is_Fixed_Length
(J
)) or else (Fixed_Length
(J
) > 0) then
3703 Make_Assignment_Statement
(Loc
,
3707 New_Occurrence_Of
(Ent
, Loc
),
3710 Low_Bound
=> To_Ityp
(Lo
),
3711 High_Bound
=> To_Ityp
(Hi
))),
3712 Expression
=> Operands
(J
));
3714 if Is_Fixed_Length
(J
) then
3715 Known_Non_Null_Operand_Seen
:= True;
3717 elsif not Known_Non_Null_Operand_Seen
then
3719 -- Here if operand length is not statically known and no
3720 -- operand known to be non-null has been processed yet.
3721 -- If operand length is 0, we do not need to perform the
3722 -- assignment, and we must avoid the evaluation of the
3723 -- high bound of the slice, since it may underflow if the
3724 -- low bound is Ityp'First.
3727 Make_Implicit_If_Statement
(Cnode
,
3731 New_Occurrence_Of
(Var_Length
(J
), Loc
),
3732 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0)),
3733 Then_Statements
=> New_List
(Assign
));
3736 Insert_Action
(Cnode
, Assign
, Suppress
=> All_Checks
);
3742 -- Finally we build the result, which is a reference to the array object
3744 Result
:= New_Occurrence_Of
(Ent
, Loc
);
3747 Rewrite
(Cnode
, Result
);
3748 Analyze_And_Resolve
(Cnode
, Atyp
);
3751 when Concatenation_Error
=>
3753 -- Kill warning generated for the declaration of the static out of
3754 -- range high bound, and instead generate a Constraint_Error with
3755 -- an appropriate specific message.
3757 Kill_Dead_Code
(Declaration_Node
(Entity
(High_Bound
)));
3758 Apply_Compile_Time_Constraint_Error
3760 Msg
=> "concatenation result upper bound out of range??",
3761 Reason
=> CE_Range_Check_Failed
);
3762 end Expand_Concatenate
;
3764 ---------------------------------------------------
3765 -- Expand_Membership_Minimize_Eliminate_Overflow --
3766 ---------------------------------------------------
3768 procedure Expand_Membership_Minimize_Eliminate_Overflow
(N
: Node_Id
) is
3769 pragma Assert
(Nkind
(N
) = N_In
);
3770 -- Despite the name, this routine applies only to N_In, not to
3771 -- N_Not_In. The latter is always rewritten as not (X in Y).
3773 Result_Type
: constant Entity_Id
:= Etype
(N
);
3774 -- Capture result type, may be a derived boolean type
3776 Loc
: constant Source_Ptr
:= Sloc
(N
);
3777 Lop
: constant Node_Id
:= Left_Opnd
(N
);
3778 Rop
: constant Node_Id
:= Right_Opnd
(N
);
3780 -- Note: there are many referencs to Etype (Lop) and Etype (Rop). It
3781 -- is thus tempting to capture these values, but due to the rewrites
3782 -- that occur as a result of overflow checking, these values change
3783 -- as we go along, and it is safe just to always use Etype explicitly.
3785 Restype
: constant Entity_Id
:= Etype
(N
);
3789 -- Bounds in Minimize calls, not used currently
3791 LLIB
: constant Entity_Id
:= Base_Type
(Standard_Long_Long_Integer
);
3792 -- Entity for Long_Long_Integer'Base (Standard should export this???)
3795 Minimize_Eliminate_Overflows
(Lop
, Lo
, Hi
, Top_Level
=> False);
3797 -- If right operand is a subtype name, and the subtype name has no
3798 -- predicate, then we can just replace the right operand with an
3799 -- explicit range T'First .. T'Last, and use the explicit range code.
3801 if Nkind
(Rop
) /= N_Range
3802 and then No
(Predicate_Function
(Etype
(Rop
)))
3805 Rtyp
: constant Entity_Id
:= Etype
(Rop
);
3810 Make_Attribute_Reference
(Loc
,
3811 Attribute_Name
=> Name_First
,
3812 Prefix
=> New_Occurrence_Of
(Rtyp
, Loc
)),
3814 Make_Attribute_Reference
(Loc
,
3815 Attribute_Name
=> Name_Last
,
3816 Prefix
=> New_Occurrence_Of
(Rtyp
, Loc
))));
3817 Analyze_And_Resolve
(Rop
, Rtyp
, Suppress
=> All_Checks
);
3821 -- Here for the explicit range case. Note that the bounds of the range
3822 -- have not been processed for minimized or eliminated checks.
3824 if Nkind
(Rop
) = N_Range
then
3825 Minimize_Eliminate_Overflows
3826 (Low_Bound
(Rop
), Lo
, Hi
, Top_Level
=> False);
3827 Minimize_Eliminate_Overflows
3828 (High_Bound
(Rop
), Lo
, Hi
, Top_Level
=> False);
3830 -- We have A in B .. C, treated as A >= B and then A <= C
3834 if Is_RTE
(Etype
(Lop
), RE_Bignum
)
3835 or else Is_RTE
(Etype
(Low_Bound
(Rop
)), RE_Bignum
)
3836 or else Is_RTE
(Etype
(High_Bound
(Rop
)), RE_Bignum
)
3839 Blk
: constant Node_Id
:= Make_Bignum_Block
(Loc
);
3840 Bnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'B', N
);
3841 L
: constant Entity_Id
:=
3842 Make_Defining_Identifier
(Loc
, Name_uL
);
3843 Lopnd
: constant Node_Id
:= Convert_To_Bignum
(Lop
);
3844 Lbound
: constant Node_Id
:=
3845 Convert_To_Bignum
(Low_Bound
(Rop
));
3846 Hbound
: constant Node_Id
:=
3847 Convert_To_Bignum
(High_Bound
(Rop
));
3849 -- Now we rewrite the membership test node to look like
3852 -- Bnn : Result_Type;
3854 -- M : Mark_Id := SS_Mark;
3855 -- L : Bignum := Lopnd;
3857 -- Bnn := Big_GE (L, Lbound) and then Big_LE (L, Hbound)
3865 -- Insert declaration of L into declarations of bignum block
3868 (Last
(Declarations
(Blk
)),
3869 Make_Object_Declaration
(Loc
,
3870 Defining_Identifier
=> L
,
3871 Object_Definition
=>
3872 New_Occurrence_Of
(RTE
(RE_Bignum
), Loc
),
3873 Expression
=> Lopnd
));
3875 -- Insert assignment to Bnn into expressions of bignum block
3878 (First
(Statements
(Handled_Statement_Sequence
(Blk
))),
3879 Make_Assignment_Statement
(Loc
,
3880 Name
=> New_Occurrence_Of
(Bnn
, Loc
),
3884 Make_Function_Call
(Loc
,
3886 New_Occurrence_Of
(RTE
(RE_Big_GE
), Loc
),
3887 Parameter_Associations
=> New_List
(
3888 New_Occurrence_Of
(L
, Loc
),
3892 Make_Function_Call
(Loc
,
3894 New_Occurrence_Of
(RTE
(RE_Big_LE
), Loc
),
3895 Parameter_Associations
=> New_List
(
3896 New_Occurrence_Of
(L
, Loc
),
3899 -- Now rewrite the node
3902 Make_Expression_With_Actions
(Loc
,
3903 Actions
=> New_List
(
3904 Make_Object_Declaration
(Loc
,
3905 Defining_Identifier
=> Bnn
,
3906 Object_Definition
=>
3907 New_Occurrence_Of
(Result_Type
, Loc
)),
3909 Expression
=> New_Occurrence_Of
(Bnn
, Loc
)));
3910 Analyze_And_Resolve
(N
, Result_Type
);
3914 -- Here if no bignums around
3917 -- Case where types are all the same
3919 if Base_Type
(Etype
(Lop
)) = Base_Type
(Etype
(Low_Bound
(Rop
)))
3921 Base_Type
(Etype
(Lop
)) = Base_Type
(Etype
(High_Bound
(Rop
)))
3925 -- If types are not all the same, it means that we have rewritten
3926 -- at least one of them to be of type Long_Long_Integer, and we
3927 -- will convert the other operands to Long_Long_Integer.
3930 Convert_To_And_Rewrite
(LLIB
, Lop
);
3931 Set_Analyzed
(Lop
, False);
3932 Analyze_And_Resolve
(Lop
, LLIB
);
3934 -- For the right operand, avoid unnecessary recursion into
3935 -- this routine, we know that overflow is not possible.
3937 Convert_To_And_Rewrite
(LLIB
, Low_Bound
(Rop
));
3938 Convert_To_And_Rewrite
(LLIB
, High_Bound
(Rop
));
3939 Set_Analyzed
(Rop
, False);
3940 Analyze_And_Resolve
(Rop
, LLIB
, Suppress
=> Overflow_Check
);
3943 -- Now the three operands are of the same signed integer type,
3944 -- so we can use the normal expansion routine for membership,
3945 -- setting the flag to prevent recursion into this procedure.
3947 Set_No_Minimize_Eliminate
(N
);
3951 -- Right operand is a subtype name and the subtype has a predicate. We
3952 -- have to make sure the predicate is checked, and for that we need to
3953 -- use the standard N_In circuitry with appropriate types.
3956 pragma Assert
(Present
(Predicate_Function
(Etype
(Rop
))));
3958 -- If types are "right", just call Expand_N_In preventing recursion
3960 if Base_Type
(Etype
(Lop
)) = Base_Type
(Etype
(Rop
)) then
3961 Set_No_Minimize_Eliminate
(N
);
3966 elsif Is_RTE
(Etype
(Lop
), RE_Bignum
) then
3968 -- For X in T, we want to rewrite our node as
3971 -- Bnn : Result_Type;
3974 -- M : Mark_Id := SS_Mark;
3975 -- Lnn : Long_Long_Integer'Base
3981 -- if not Bignum_In_LLI_Range (Nnn) then
3984 -- Lnn := From_Bignum (Nnn);
3986 -- Lnn in LLIB (T'Base'First) .. LLIB (T'Base'Last)
3987 -- and then T'Base (Lnn) in T;
3996 -- A bit gruesome, but there doesn't seem to be a simpler way
3999 Blk
: constant Node_Id
:= Make_Bignum_Block
(Loc
);
4000 Bnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'B', N
);
4001 Lnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'L', N
);
4002 Nnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'N', N
);
4003 T
: constant Entity_Id
:= Etype
(Rop
);
4004 TB
: constant Entity_Id
:= Base_Type
(T
);
4008 -- Mark the last membership operation to prevent recursion
4012 Left_Opnd
=> Convert_To
(TB
, New_Occurrence_Of
(Lnn
, Loc
)),
4013 Right_Opnd
=> New_Occurrence_Of
(T
, Loc
));
4014 Set_No_Minimize_Eliminate
(Nin
);
4016 -- Now decorate the block
4019 (Last
(Declarations
(Blk
)),
4020 Make_Object_Declaration
(Loc
,
4021 Defining_Identifier
=> Lnn
,
4022 Object_Definition
=> New_Occurrence_Of
(LLIB
, Loc
)));
4025 (Last
(Declarations
(Blk
)),
4026 Make_Object_Declaration
(Loc
,
4027 Defining_Identifier
=> Nnn
,
4028 Object_Definition
=>
4029 New_Occurrence_Of
(RTE
(RE_Bignum
), Loc
)));
4032 (First
(Statements
(Handled_Statement_Sequence
(Blk
))),
4034 Make_Assignment_Statement
(Loc
,
4035 Name
=> New_Occurrence_Of
(Nnn
, Loc
),
4036 Expression
=> Relocate_Node
(Lop
)),
4038 Make_Implicit_If_Statement
(N
,
4042 Make_Function_Call
(Loc
,
4045 (RTE
(RE_Bignum_In_LLI_Range
), Loc
),
4046 Parameter_Associations
=> New_List
(
4047 New_Occurrence_Of
(Nnn
, Loc
)))),
4049 Then_Statements
=> New_List
(
4050 Make_Assignment_Statement
(Loc
,
4051 Name
=> New_Occurrence_Of
(Bnn
, Loc
),
4053 New_Occurrence_Of
(Standard_False
, Loc
))),
4055 Else_Statements
=> New_List
(
4056 Make_Assignment_Statement
(Loc
,
4057 Name
=> New_Occurrence_Of
(Lnn
, Loc
),
4059 Make_Function_Call
(Loc
,
4061 New_Occurrence_Of
(RTE
(RE_From_Bignum
), Loc
),
4062 Parameter_Associations
=> New_List
(
4063 New_Occurrence_Of
(Nnn
, Loc
)))),
4065 Make_Assignment_Statement
(Loc
,
4066 Name
=> New_Occurrence_Of
(Bnn
, Loc
),
4071 Left_Opnd
=> New_Occurrence_Of
(Lnn
, Loc
),
4076 Make_Attribute_Reference
(Loc
,
4077 Attribute_Name
=> Name_First
,
4079 New_Occurrence_Of
(TB
, Loc
))),
4083 Make_Attribute_Reference
(Loc
,
4084 Attribute_Name
=> Name_Last
,
4086 New_Occurrence_Of
(TB
, Loc
))))),
4088 Right_Opnd
=> Nin
))))));
4090 -- Now we can do the rewrite
4093 Make_Expression_With_Actions
(Loc
,
4094 Actions
=> New_List
(
4095 Make_Object_Declaration
(Loc
,
4096 Defining_Identifier
=> Bnn
,
4097 Object_Definition
=>
4098 New_Occurrence_Of
(Result_Type
, Loc
)),
4100 Expression
=> New_Occurrence_Of
(Bnn
, Loc
)));
4101 Analyze_And_Resolve
(N
, Result_Type
);
4105 -- Not bignum case, but types don't match (this means we rewrote the
4106 -- left operand to be Long_Long_Integer).
4109 pragma Assert
(Base_Type
(Etype
(Lop
)) = LLIB
);
4111 -- We rewrite the membership test as (where T is the type with
4112 -- the predicate, i.e. the type of the right operand)
4114 -- Lop in LLIB (T'Base'First) .. LLIB (T'Base'Last)
4115 -- and then T'Base (Lop) in T
4118 T
: constant Entity_Id
:= Etype
(Rop
);
4119 TB
: constant Entity_Id
:= Base_Type
(T
);
4123 -- The last membership test is marked to prevent recursion
4127 Left_Opnd
=> Convert_To
(TB
, Duplicate_Subexpr
(Lop
)),
4128 Right_Opnd
=> New_Occurrence_Of
(T
, Loc
));
4129 Set_No_Minimize_Eliminate
(Nin
);
4131 -- Now do the rewrite
4142 Make_Attribute_Reference
(Loc
,
4143 Attribute_Name
=> Name_First
,
4145 New_Occurrence_Of
(TB
, Loc
))),
4148 Make_Attribute_Reference
(Loc
,
4149 Attribute_Name
=> Name_Last
,
4151 New_Occurrence_Of
(TB
, Loc
))))),
4152 Right_Opnd
=> Nin
));
4153 Set_Analyzed
(N
, False);
4154 Analyze_And_Resolve
(N
, Restype
);
4158 end Expand_Membership_Minimize_Eliminate_Overflow
;
4160 ------------------------
4161 -- Expand_N_Allocator --
4162 ------------------------
4164 procedure Expand_N_Allocator
(N
: Node_Id
) is
4165 Etyp
: constant Entity_Id
:= Etype
(Expression
(N
));
4166 Loc
: constant Source_Ptr
:= Sloc
(N
);
4167 PtrT
: constant Entity_Id
:= Etype
(N
);
4169 procedure Rewrite_Coextension
(N
: Node_Id
);
4170 -- Static coextensions have the same lifetime as the entity they
4171 -- constrain. Such occurrences can be rewritten as aliased objects
4172 -- and their unrestricted access used instead of the coextension.
4174 function Size_In_Storage_Elements
(E
: Entity_Id
) return Node_Id
;
4175 -- Given a constrained array type E, returns a node representing the
4176 -- code to compute the size in storage elements for the given type.
4177 -- This is done without using the attribute (which malfunctions for
4180 -------------------------
4181 -- Rewrite_Coextension --
4182 -------------------------
4184 procedure Rewrite_Coextension
(N
: Node_Id
) is
4185 Temp_Id
: constant Node_Id
:= Make_Temporary
(Loc
, 'C');
4186 Temp_Decl
: Node_Id
;
4190 -- Cnn : aliased Etyp;
4193 Make_Object_Declaration
(Loc
,
4194 Defining_Identifier
=> Temp_Id
,
4195 Aliased_Present
=> True,
4196 Object_Definition
=> New_Occurrence_Of
(Etyp
, Loc
));
4198 if Nkind
(Expression
(N
)) = N_Qualified_Expression
then
4199 Set_Expression
(Temp_Decl
, Expression
(Expression
(N
)));
4202 Insert_Action
(N
, Temp_Decl
);
4204 Make_Attribute_Reference
(Loc
,
4205 Prefix
=> New_Occurrence_Of
(Temp_Id
, Loc
),
4206 Attribute_Name
=> Name_Unrestricted_Access
));
4208 Analyze_And_Resolve
(N
, PtrT
);
4209 end Rewrite_Coextension
;
4211 ------------------------------
4212 -- Size_In_Storage_Elements --
4213 ------------------------------
4215 function Size_In_Storage_Elements
(E
: Entity_Id
) return Node_Id
is
4217 -- Logically this just returns E'Max_Size_In_Storage_Elements.
4218 -- However, the reason for the existence of this function is
4219 -- to construct a test for sizes too large, which means near the
4220 -- 32-bit limit on a 32-bit machine, and precisely the trouble
4221 -- is that we get overflows when sizes are greater than 2**31.
4223 -- So what we end up doing for array types is to use the expression:
4225 -- number-of-elements * component_type'Max_Size_In_Storage_Elements
4227 -- which avoids this problem. All this is a bit bogus, but it does
4228 -- mean we catch common cases of trying to allocate arrays that
4229 -- are too large, and which in the absence of a check results in
4230 -- undetected chaos ???
4232 -- Note in particular that this is a pessimistic estimate in the
4233 -- case of packed array types, where an array element might occupy
4234 -- just a fraction of a storage element???
4241 for J
in 1 .. Number_Dimensions
(E
) loop
4243 Make_Attribute_Reference
(Loc
,
4244 Prefix
=> New_Occurrence_Of
(E
, Loc
),
4245 Attribute_Name
=> Name_Length
,
4246 Expressions
=> New_List
(Make_Integer_Literal
(Loc
, J
)));
4253 Make_Op_Multiply
(Loc
,
4260 Make_Op_Multiply
(Loc
,
4263 Make_Attribute_Reference
(Loc
,
4264 Prefix
=> New_Occurrence_Of
(Component_Type
(E
), Loc
),
4265 Attribute_Name
=> Name_Max_Size_In_Storage_Elements
));
4267 end Size_In_Storage_Elements
;
4271 Dtyp
: constant Entity_Id
:= Available_View
(Designated_Type
(PtrT
));
4275 Rel_Typ
: Entity_Id
;
4278 -- Start of processing for Expand_N_Allocator
4281 -- RM E.2.3(22). We enforce that the expected type of an allocator
4282 -- shall not be a remote access-to-class-wide-limited-private type
4284 -- Why is this being done at expansion time, seems clearly wrong ???
4286 Validate_Remote_Access_To_Class_Wide_Type
(N
);
4288 -- Processing for anonymous access-to-controlled types. These access
4289 -- types receive a special finalization master which appears in the
4290 -- declarations of the enclosing semantic unit. This expansion is done
4291 -- now to ensure that any additional types generated by this routine or
4292 -- Expand_Allocator_Expression inherit the proper type attributes.
4294 if (Ekind
(PtrT
) = E_Anonymous_Access_Type
4295 or else (Is_Itype
(PtrT
) and then No
(Finalization_Master
(PtrT
))))
4296 and then Needs_Finalization
(Dtyp
)
4298 -- Detect the allocation of an anonymous controlled object where the
4299 -- type of the context is named. For example:
4301 -- procedure Proc (Ptr : Named_Access_Typ);
4302 -- Proc (new Designated_Typ);
4304 -- Regardless of the anonymous-to-named access type conversion, the
4305 -- lifetime of the object must be associated with the named access
4306 -- type. Use the finalization-related attributes of this type.
4308 if Nkind_In
(Parent
(N
), N_Type_Conversion
,
4309 N_Unchecked_Type_Conversion
)
4310 and then Ekind_In
(Etype
(Parent
(N
)), E_Access_Subtype
,
4312 E_General_Access_Type
)
4314 Rel_Typ
:= Etype
(Parent
(N
));
4319 -- Anonymous access-to-controlled types allocate on the global pool.
4320 -- Do not set this attribute on .NET/JVM since those targets do not
4323 if No
(Associated_Storage_Pool
(PtrT
)) and then VM_Target
= No_VM
then
4324 if Present
(Rel_Typ
) then
4325 Set_Associated_Storage_Pool
4326 (PtrT
, Associated_Storage_Pool
(Rel_Typ
));
4328 Set_Associated_Storage_Pool
4329 (PtrT
, RTE
(RE_Global_Pool_Object
));
4333 -- The finalization master must be inserted and analyzed as part of
4334 -- the current semantic unit. Note that the master is updated when
4335 -- analysis changes current units.
4337 if Present
(Rel_Typ
) then
4338 Set_Finalization_Master
(PtrT
, Finalization_Master
(Rel_Typ
));
4340 Set_Finalization_Master
(PtrT
, Current_Anonymous_Master
);
4344 -- Set the storage pool and find the appropriate version of Allocate to
4345 -- call. Do not overwrite the storage pool if it is already set, which
4346 -- can happen for build-in-place function returns (see
4347 -- Exp_Ch4.Expand_N_Extended_Return_Statement).
4349 if No
(Storage_Pool
(N
)) then
4350 Pool
:= Associated_Storage_Pool
(Root_Type
(PtrT
));
4352 if Present
(Pool
) then
4353 Set_Storage_Pool
(N
, Pool
);
4355 if Is_RTE
(Pool
, RE_SS_Pool
) then
4356 if VM_Target
= No_VM
then
4357 Set_Procedure_To_Call
(N
, RTE
(RE_SS_Allocate
));
4360 -- In the case of an allocator for a simple storage pool, locate
4361 -- and save a reference to the pool type's Allocate routine.
4363 elsif Present
(Get_Rep_Pragma
4364 (Etype
(Pool
), Name_Simple_Storage_Pool_Type
))
4367 Pool_Type
: constant Entity_Id
:= Base_Type
(Etype
(Pool
));
4368 Alloc_Op
: Entity_Id
;
4370 Alloc_Op
:= Get_Name_Entity_Id
(Name_Allocate
);
4371 while Present
(Alloc_Op
) loop
4372 if Scope
(Alloc_Op
) = Scope
(Pool_Type
)
4373 and then Present
(First_Formal
(Alloc_Op
))
4374 and then Etype
(First_Formal
(Alloc_Op
)) = Pool_Type
4376 Set_Procedure_To_Call
(N
, Alloc_Op
);
4379 Alloc_Op
:= Homonym
(Alloc_Op
);
4384 elsif Is_Class_Wide_Type
(Etype
(Pool
)) then
4385 Set_Procedure_To_Call
(N
, RTE
(RE_Allocate_Any
));
4388 Set_Procedure_To_Call
(N
,
4389 Find_Prim_Op
(Etype
(Pool
), Name_Allocate
));
4394 -- Under certain circumstances we can replace an allocator by an access
4395 -- to statically allocated storage. The conditions, as noted in AARM
4396 -- 3.10 (10c) are as follows:
4398 -- Size and initial value is known at compile time
4399 -- Access type is access-to-constant
4401 -- The allocator is not part of a constraint on a record component,
4402 -- because in that case the inserted actions are delayed until the
4403 -- record declaration is fully analyzed, which is too late for the
4404 -- analysis of the rewritten allocator.
4406 if Is_Access_Constant
(PtrT
)
4407 and then Nkind
(Expression
(N
)) = N_Qualified_Expression
4408 and then Compile_Time_Known_Value
(Expression
(Expression
(N
)))
4409 and then Size_Known_At_Compile_Time
4410 (Etype
(Expression
(Expression
(N
))))
4411 and then not Is_Record_Type
(Current_Scope
)
4413 -- Here we can do the optimization. For the allocator
4417 -- We insert an object declaration
4419 -- Tnn : aliased x := y;
4421 -- and replace the allocator by Tnn'Unrestricted_Access. Tnn is
4422 -- marked as requiring static allocation.
4424 Temp
:= Make_Temporary
(Loc
, 'T', Expression
(Expression
(N
)));
4425 Desig
:= Subtype_Mark
(Expression
(N
));
4427 -- If context is constrained, use constrained subtype directly,
4428 -- so that the constant is not labelled as having a nominally
4429 -- unconstrained subtype.
4431 if Entity
(Desig
) = Base_Type
(Dtyp
) then
4432 Desig
:= New_Occurrence_Of
(Dtyp
, Loc
);
4436 Make_Object_Declaration
(Loc
,
4437 Defining_Identifier
=> Temp
,
4438 Aliased_Present
=> True,
4439 Constant_Present
=> Is_Access_Constant
(PtrT
),
4440 Object_Definition
=> Desig
,
4441 Expression
=> Expression
(Expression
(N
))));
4444 Make_Attribute_Reference
(Loc
,
4445 Prefix
=> New_Occurrence_Of
(Temp
, Loc
),
4446 Attribute_Name
=> Name_Unrestricted_Access
));
4448 Analyze_And_Resolve
(N
, PtrT
);
4450 -- We set the variable as statically allocated, since we don't want
4451 -- it going on the stack of the current procedure.
4453 Set_Is_Statically_Allocated
(Temp
);
4457 -- Same if the allocator is an access discriminant for a local object:
4458 -- instead of an allocator we create a local value and constrain the
4459 -- enclosing object with the corresponding access attribute.
4461 if Is_Static_Coextension
(N
) then
4462 Rewrite_Coextension
(N
);
4466 -- Check for size too large, we do this because the back end misses
4467 -- proper checks here and can generate rubbish allocation calls when
4468 -- we are near the limit. We only do this for the 32-bit address case
4469 -- since that is from a practical point of view where we see a problem.
4471 if System_Address_Size
= 32
4472 and then not Storage_Checks_Suppressed
(PtrT
)
4473 and then not Storage_Checks_Suppressed
(Dtyp
)
4474 and then not Storage_Checks_Suppressed
(Etyp
)
4476 -- The check we want to generate should look like
4478 -- if Etyp'Max_Size_In_Storage_Elements > 3.5 gigabytes then
4479 -- raise Storage_Error;
4482 -- where 3.5 gigabytes is a constant large enough to accommodate any
4483 -- reasonable request for. But we can't do it this way because at
4484 -- least at the moment we don't compute this attribute right, and
4485 -- can silently give wrong results when the result gets large. Since
4486 -- this is all about large results, that's bad, so instead we only
4487 -- apply the check for constrained arrays, and manually compute the
4488 -- value of the attribute ???
4490 if Is_Array_Type
(Etyp
) and then Is_Constrained
(Etyp
) then
4492 Make_Raise_Storage_Error
(Loc
,
4495 Left_Opnd
=> Size_In_Storage_Elements
(Etyp
),
4497 Make_Integer_Literal
(Loc
, Uint_7
* (Uint_2
** 29))),
4498 Reason
=> SE_Object_Too_Large
));
4502 -- If no storage pool has been specified and we have the restriction
4503 -- No_Standard_Allocators_After_Elaboration is present, then generate
4504 -- a call to Elaboration_Allocators.Check_Standard_Allocator.
4506 if Nkind
(N
) = N_Allocator
4507 and then No
(Storage_Pool
(N
))
4508 and then Restriction_Active
(No_Standard_Allocators_After_Elaboration
)
4511 Make_Procedure_Call_Statement
(Loc
,
4513 New_Occurrence_Of
(RTE
(RE_Check_Standard_Allocator
), Loc
)));
4516 -- Handle case of qualified expression (other than optimization above)
4517 -- First apply constraint checks, because the bounds or discriminants
4518 -- in the aggregate might not match the subtype mark in the allocator.
4520 if Nkind
(Expression
(N
)) = N_Qualified_Expression
then
4521 Apply_Constraint_Check
4522 (Expression
(Expression
(N
)), Etype
(Expression
(N
)));
4524 Expand_Allocator_Expression
(N
);
4528 -- If the allocator is for a type which requires initialization, and
4529 -- there is no initial value (i.e. operand is a subtype indication
4530 -- rather than a qualified expression), then we must generate a call to
4531 -- the initialization routine using an expressions action node:
4533 -- [Pnnn : constant ptr_T := new (T); Init (Pnnn.all,...); Pnnn]
4535 -- Here ptr_T is the pointer type for the allocator, and T is the
4536 -- subtype of the allocator. A special case arises if the designated
4537 -- type of the access type is a task or contains tasks. In this case
4538 -- the call to Init (Temp.all ...) is replaced by code that ensures
4539 -- that tasks get activated (see Exp_Ch9.Build_Task_Allocate_Block
4540 -- for details). In addition, if the type T is a task type, then the
4541 -- first argument to Init must be converted to the task record type.
4544 T
: constant Entity_Id
:= Entity
(Expression
(N
));
4550 Init_Arg1
: Node_Id
;
4551 Temp_Decl
: Node_Id
;
4552 Temp_Type
: Entity_Id
;
4555 if No_Initialization
(N
) then
4557 -- Even though this might be a simple allocation, create a custom
4558 -- Allocate if the context requires it. Since .NET/JVM compilers
4559 -- do not support pools, this step is skipped.
4561 if VM_Target
= No_VM
4562 and then Present
(Finalization_Master
(PtrT
))
4564 Build_Allocate_Deallocate_Proc
4566 Is_Allocate
=> True);
4569 -- Case of no initialization procedure present
4571 elsif not Has_Non_Null_Base_Init_Proc
(T
) then
4573 -- Case of simple initialization required
4575 if Needs_Simple_Initialization
(T
) then
4576 Check_Restriction
(No_Default_Initialization
, N
);
4577 Rewrite
(Expression
(N
),
4578 Make_Qualified_Expression
(Loc
,
4579 Subtype_Mark
=> New_Occurrence_Of
(T
, Loc
),
4580 Expression
=> Get_Simple_Init_Val
(T
, N
)));
4582 Analyze_And_Resolve
(Expression
(Expression
(N
)), T
);
4583 Analyze_And_Resolve
(Expression
(N
), T
);
4584 Set_Paren_Count
(Expression
(Expression
(N
)), 1);
4585 Expand_N_Allocator
(N
);
4587 -- No initialization required
4593 -- Case of initialization procedure present, must be called
4596 Check_Restriction
(No_Default_Initialization
, N
);
4598 if not Restriction_Active
(No_Default_Initialization
) then
4599 Init
:= Base_Init_Proc
(T
);
4601 Temp
:= Make_Temporary
(Loc
, 'P');
4603 -- Construct argument list for the initialization routine call
4606 Make_Explicit_Dereference
(Loc
,
4608 New_Occurrence_Of
(Temp
, Loc
));
4610 Set_Assignment_OK
(Init_Arg1
);
4613 -- The initialization procedure expects a specific type. if the
4614 -- context is access to class wide, indicate that the object
4615 -- being allocated has the right specific type.
4617 if Is_Class_Wide_Type
(Dtyp
) then
4618 Init_Arg1
:= Unchecked_Convert_To
(T
, Init_Arg1
);
4621 -- If designated type is a concurrent type or if it is private
4622 -- type whose definition is a concurrent type, the first
4623 -- argument in the Init routine has to be unchecked conversion
4624 -- to the corresponding record type. If the designated type is
4625 -- a derived type, also convert the argument to its root type.
4627 if Is_Concurrent_Type
(T
) then
4629 Unchecked_Convert_To
(
4630 Corresponding_Record_Type
(T
), Init_Arg1
);
4632 elsif Is_Private_Type
(T
)
4633 and then Present
(Full_View
(T
))
4634 and then Is_Concurrent_Type
(Full_View
(T
))
4637 Unchecked_Convert_To
4638 (Corresponding_Record_Type
(Full_View
(T
)), Init_Arg1
);
4640 elsif Etype
(First_Formal
(Init
)) /= Base_Type
(T
) then
4642 Ftyp
: constant Entity_Id
:= Etype
(First_Formal
(Init
));
4645 Init_Arg1
:= OK_Convert_To
(Etype
(Ftyp
), Init_Arg1
);
4646 Set_Etype
(Init_Arg1
, Ftyp
);
4650 Args
:= New_List
(Init_Arg1
);
4652 -- For the task case, pass the Master_Id of the access type as
4653 -- the value of the _Master parameter, and _Chain as the value
4654 -- of the _Chain parameter (_Chain will be defined as part of
4655 -- the generated code for the allocator).
4657 -- In Ada 2005, the context may be a function that returns an
4658 -- anonymous access type. In that case the Master_Id has been
4659 -- created when expanding the function declaration.
4661 if Has_Task
(T
) then
4662 if No
(Master_Id
(Base_Type
(PtrT
))) then
4664 -- The designated type was an incomplete type, and the
4665 -- access type did not get expanded. Salvage it now.
4667 if not Restriction_Active
(No_Task_Hierarchy
) then
4668 if Present
(Parent
(Base_Type
(PtrT
))) then
4669 Expand_N_Full_Type_Declaration
4670 (Parent
(Base_Type
(PtrT
)));
4672 -- The only other possibility is an itype. For this
4673 -- case, the master must exist in the context. This is
4674 -- the case when the allocator initializes an access
4675 -- component in an init-proc.
4678 pragma Assert
(Is_Itype
(PtrT
));
4679 Build_Master_Renaming
(PtrT
, N
);
4684 -- If the context of the allocator is a declaration or an
4685 -- assignment, we can generate a meaningful image for it,
4686 -- even though subsequent assignments might remove the
4687 -- connection between task and entity. We build this image
4688 -- when the left-hand side is a simple variable, a simple
4689 -- indexed assignment or a simple selected component.
4691 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
4693 Nam
: constant Node_Id
:= Name
(Parent
(N
));
4696 if Is_Entity_Name
(Nam
) then
4698 Build_Task_Image_Decls
4701 (Entity
(Nam
), Sloc
(Nam
)), T
);
4703 elsif Nkind_In
(Nam
, N_Indexed_Component
,
4704 N_Selected_Component
)
4705 and then Is_Entity_Name
(Prefix
(Nam
))
4708 Build_Task_Image_Decls
4709 (Loc
, Nam
, Etype
(Prefix
(Nam
)));
4711 Decls
:= Build_Task_Image_Decls
(Loc
, T
, T
);
4715 elsif Nkind
(Parent
(N
)) = N_Object_Declaration
then
4717 Build_Task_Image_Decls
4718 (Loc
, Defining_Identifier
(Parent
(N
)), T
);
4721 Decls
:= Build_Task_Image_Decls
(Loc
, T
, T
);
4724 if Restriction_Active
(No_Task_Hierarchy
) then
4726 New_Occurrence_Of
(RTE
(RE_Library_Task_Level
), Loc
));
4730 (Master_Id
(Base_Type
(Root_Type
(PtrT
))), Loc
));
4733 Append_To
(Args
, Make_Identifier
(Loc
, Name_uChain
));
4735 Decl
:= Last
(Decls
);
4737 New_Occurrence_Of
(Defining_Identifier
(Decl
), Loc
));
4739 -- Has_Task is false, Decls not used
4745 -- Add discriminants if discriminated type
4748 Dis
: Boolean := False;
4752 if Has_Discriminants
(T
) then
4756 elsif Is_Private_Type
(T
)
4757 and then Present
(Full_View
(T
))
4758 and then Has_Discriminants
(Full_View
(T
))
4761 Typ
:= Full_View
(T
);
4766 -- If the allocated object will be constrained by the
4767 -- default values for discriminants, then build a subtype
4768 -- with those defaults, and change the allocated subtype
4769 -- to that. Note that this happens in fewer cases in Ada
4772 if not Is_Constrained
(Typ
)
4773 and then Present
(Discriminant_Default_Value
4774 (First_Discriminant
(Typ
)))
4775 and then (Ada_Version
< Ada_2005
4777 Object_Type_Has_Constrained_Partial_View
4778 (Typ
, Current_Scope
))
4780 Typ
:= Build_Default_Subtype
(Typ
, N
);
4781 Set_Expression
(N
, New_Occurrence_Of
(Typ
, Loc
));
4784 Discr
:= First_Elmt
(Discriminant_Constraint
(Typ
));
4785 while Present
(Discr
) loop
4786 Nod
:= Node
(Discr
);
4787 Append
(New_Copy_Tree
(Node
(Discr
)), Args
);
4789 -- AI-416: when the discriminant constraint is an
4790 -- anonymous access type make sure an accessibility
4791 -- check is inserted if necessary (3.10.2(22.q/2))
4793 if Ada_Version
>= Ada_2005
4795 Ekind
(Etype
(Nod
)) = E_Anonymous_Access_Type
4797 Apply_Accessibility_Check
4798 (Nod
, Typ
, Insert_Node
=> Nod
);
4806 -- We set the allocator as analyzed so that when we analyze
4807 -- the if expression node, we do not get an unwanted recursive
4808 -- expansion of the allocator expression.
4810 Set_Analyzed
(N
, True);
4811 Nod
:= Relocate_Node
(N
);
4813 -- Here is the transformation:
4814 -- input: new Ctrl_Typ
4815 -- output: Temp : constant Ctrl_Typ_Ptr := new Ctrl_Typ;
4816 -- Ctrl_TypIP (Temp.all, ...);
4817 -- [Deep_]Initialize (Temp.all);
4819 -- Here Ctrl_Typ_Ptr is the pointer type for the allocator, and
4820 -- is the subtype of the allocator.
4823 Make_Object_Declaration
(Loc
,
4824 Defining_Identifier
=> Temp
,
4825 Constant_Present
=> True,
4826 Object_Definition
=> New_Occurrence_Of
(Temp_Type
, Loc
),
4829 Set_Assignment_OK
(Temp_Decl
);
4830 Insert_Action
(N
, Temp_Decl
, Suppress
=> All_Checks
);
4832 Build_Allocate_Deallocate_Proc
(Temp_Decl
, True);
4834 -- If the designated type is a task type or contains tasks,
4835 -- create block to activate created tasks, and insert
4836 -- declaration for Task_Image variable ahead of call.
4838 if Has_Task
(T
) then
4840 L
: constant List_Id
:= New_List
;
4843 Build_Task_Allocate_Block
(L
, Nod
, Args
);
4845 Insert_List_Before
(First
(Declarations
(Blk
)), Decls
);
4846 Insert_Actions
(N
, L
);
4851 Make_Procedure_Call_Statement
(Loc
,
4852 Name
=> New_Occurrence_Of
(Init
, Loc
),
4853 Parameter_Associations
=> Args
));
4856 if Needs_Finalization
(T
) then
4859 -- [Deep_]Initialize (Init_Arg1);
4863 (Obj_Ref
=> New_Copy_Tree
(Init_Arg1
),
4866 if Present
(Finalization_Master
(PtrT
)) then
4868 -- Special processing for .NET/JVM, the allocated object
4869 -- is attached to the finalization master. Generate:
4871 -- Attach (<PtrT>FM, Root_Controlled_Ptr (Init_Arg1));
4873 -- Types derived from [Limited_]Controlled are the only
4874 -- ones considered since they have fields Prev and Next.
4876 if VM_Target
/= No_VM
then
4877 if Is_Controlled
(T
) then
4880 (Obj_Ref
=> New_Copy_Tree
(Init_Arg1
),
4884 -- Default case, generate:
4886 -- Set_Finalize_Address
4887 -- (<PtrT>FM, <T>FD'Unrestricted_Access);
4889 -- Do not generate this call in CodePeer mode, as TSS
4890 -- primitive Finalize_Address is not created in this
4893 elsif not CodePeer_Mode
then
4895 Make_Set_Finalize_Address_Call
4903 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
4904 Analyze_And_Resolve
(N
, PtrT
);
4909 -- Ada 2005 (AI-251): If the allocator is for a class-wide interface
4910 -- object that has been rewritten as a reference, we displace "this"
4911 -- to reference properly its secondary dispatch table.
4913 if Nkind
(N
) = N_Identifier
and then Is_Interface
(Dtyp
) then
4914 Displace_Allocator_Pointer
(N
);
4918 when RE_Not_Available
=>
4920 end Expand_N_Allocator
;
4922 -----------------------
4923 -- Expand_N_And_Then --
4924 -----------------------
4926 procedure Expand_N_And_Then
(N
: Node_Id
)
4927 renames Expand_Short_Circuit_Operator
;
4929 ------------------------------
4930 -- Expand_N_Case_Expression --
4931 ------------------------------
4933 procedure Expand_N_Case_Expression
(N
: Node_Id
) is
4934 Loc
: constant Source_Ptr
:= Sloc
(N
);
4935 Typ
: constant Entity_Id
:= Etype
(N
);
4946 -- Check for MINIMIZED/ELIMINATED overflow mode
4948 if Minimized_Eliminated_Overflow_Check
(N
) then
4949 Apply_Arithmetic_Overflow_Check
(N
);
4953 -- If the case expression is a predicate specification, do not
4954 -- expand, because it will be converted to the proper predicate
4955 -- form when building the predicate function.
4957 if Ekind_In
(Current_Scope
, E_Function
, E_Procedure
)
4958 and then Is_Predicate_Function
(Current_Scope
)
4965 -- case X is when A => AX, when B => BX ...
4980 -- However, this expansion is wrong for limited types, and also
4981 -- wrong for unconstrained types (since the bounds may not be the
4982 -- same in all branches). Furthermore it involves an extra copy
4983 -- for large objects. So we take care of this by using the following
4984 -- modified expansion for non-elementary types:
4987 -- type Pnn is access all typ;
4991 -- T := AX'Unrestricted_Access;
4993 -- T := BX'Unrestricted_Access;
4999 Make_Case_Statement
(Loc
,
5000 Expression
=> Expression
(N
),
5001 Alternatives
=> New_List
);
5003 -- Preserve the original context for which the case statement is being
5004 -- generated. This is needed by the finalization machinery to prevent
5005 -- the premature finalization of controlled objects found within the
5008 Set_From_Conditional_Expression
(Cstmt
);
5010 Actions
:= New_List
;
5014 if Is_Elementary_Type
(Typ
) then
5018 Pnn
:= Make_Temporary
(Loc
, 'P');
5020 Make_Full_Type_Declaration
(Loc
,
5021 Defining_Identifier
=> Pnn
,
5023 Make_Access_To_Object_Definition
(Loc
,
5024 All_Present
=> True,
5025 Subtype_Indication
=> New_Occurrence_Of
(Typ
, Loc
))));
5029 Tnn
:= Make_Temporary
(Loc
, 'T');
5031 -- Create declaration for target of expression, and indicate that it
5032 -- does not require initialization.
5035 Make_Object_Declaration
(Loc
,
5036 Defining_Identifier
=> Tnn
,
5037 Object_Definition
=> New_Occurrence_Of
(Ttyp
, Loc
));
5038 Set_No_Initialization
(Decl
);
5039 Append_To
(Actions
, Decl
);
5041 -- Now process the alternatives
5043 Alt
:= First
(Alternatives
(N
));
5044 while Present
(Alt
) loop
5046 Aexp
: Node_Id
:= Expression
(Alt
);
5047 Aloc
: constant Source_Ptr
:= Sloc
(Aexp
);
5051 -- As described above, take Unrestricted_Access for case of non-
5052 -- scalar types, to avoid big copies, and special cases.
5054 if not Is_Elementary_Type
(Typ
) then
5056 Make_Attribute_Reference
(Aloc
,
5057 Prefix
=> Relocate_Node
(Aexp
),
5058 Attribute_Name
=> Name_Unrestricted_Access
);
5062 Make_Assignment_Statement
(Aloc
,
5063 Name
=> New_Occurrence_Of
(Tnn
, Loc
),
5064 Expression
=> Aexp
));
5066 -- Propagate declarations inserted in the node by Insert_Actions
5067 -- (for example, temporaries generated to remove side effects).
5068 -- These actions must remain attached to the alternative, given
5069 -- that they are generated by the corresponding expression.
5071 if Present
(Sinfo
.Actions
(Alt
)) then
5072 Prepend_List
(Sinfo
.Actions
(Alt
), Stats
);
5076 (Alternatives
(Cstmt
),
5077 Make_Case_Statement_Alternative
(Sloc
(Alt
),
5078 Discrete_Choices
=> Discrete_Choices
(Alt
),
5079 Statements
=> Stats
));
5085 Append_To
(Actions
, Cstmt
);
5087 -- Construct and return final expression with actions
5089 if Is_Elementary_Type
(Typ
) then
5090 Fexp
:= New_Occurrence_Of
(Tnn
, Loc
);
5093 Make_Explicit_Dereference
(Loc
,
5094 Prefix
=> New_Occurrence_Of
(Tnn
, Loc
));
5098 Make_Expression_With_Actions
(Loc
,
5100 Actions
=> Actions
));
5102 Analyze_And_Resolve
(N
, Typ
);
5103 end Expand_N_Case_Expression
;
5105 -----------------------------------
5106 -- Expand_N_Explicit_Dereference --
5107 -----------------------------------
5109 procedure Expand_N_Explicit_Dereference
(N
: Node_Id
) is
5111 -- Insert explicit dereference call for the checked storage pool case
5113 Insert_Dereference_Action
(Prefix
(N
));
5115 -- If the type is an Atomic type for which Atomic_Sync is enabled, then
5116 -- we set the atomic sync flag.
5118 if Is_Atomic
(Etype
(N
))
5119 and then not Atomic_Synchronization_Disabled
(Etype
(N
))
5121 Activate_Atomic_Synchronization
(N
);
5123 end Expand_N_Explicit_Dereference
;
5125 --------------------------------------
5126 -- Expand_N_Expression_With_Actions --
5127 --------------------------------------
5129 procedure Expand_N_Expression_With_Actions
(N
: Node_Id
) is
5131 function Process_Action
(Act
: Node_Id
) return Traverse_Result
;
5132 -- Inspect and process a single action of an expression_with_actions for
5133 -- transient controlled objects. If such objects are found, the routine
5134 -- generates code to clean them up when the context of the expression is
5135 -- evaluated or elaborated.
5137 --------------------
5138 -- Process_Action --
5139 --------------------
5141 function Process_Action
(Act
: Node_Id
) return Traverse_Result
is
5143 if Nkind
(Act
) = N_Object_Declaration
5144 and then Is_Finalizable_Transient
(Act
, N
)
5146 Process_Transient_Object
(Act
, N
);
5149 -- Avoid processing temporary function results multiple times when
5150 -- dealing with nested expression_with_actions.
5152 elsif Nkind
(Act
) = N_Expression_With_Actions
then
5155 -- Do not process temporary function results in loops. This is done
5156 -- by Expand_N_Loop_Statement and Build_Finalizer.
5158 elsif Nkind
(Act
) = N_Loop_Statement
then
5165 procedure Process_Single_Action
is new Traverse_Proc
(Process_Action
);
5171 -- Start of processing for Expand_N_Expression_With_Actions
5174 -- Process the actions as described above
5176 Act
:= First
(Actions
(N
));
5177 while Present
(Act
) loop
5178 Process_Single_Action
(Act
);
5182 -- Deal with case where there are no actions. In this case we simply
5183 -- rewrite the node with its expression since we don't need the actions
5184 -- and the specification of this node does not allow a null action list.
5186 -- Note: we use Rewrite instead of Replace, because Codepeer is using
5187 -- the expanded tree and relying on being able to retrieve the original
5188 -- tree in cases like this. This raises a whole lot of issues of whether
5189 -- we have problems elsewhere, which will be addressed in the future???
5191 if Is_Empty_List
(Actions
(N
)) then
5192 Rewrite
(N
, Relocate_Node
(Expression
(N
)));
5194 end Expand_N_Expression_With_Actions
;
5196 ----------------------------
5197 -- Expand_N_If_Expression --
5198 ----------------------------
5200 -- Deal with limited types and condition actions
5202 procedure Expand_N_If_Expression
(N
: Node_Id
) is
5203 procedure Process_Actions
(Actions
: List_Id
);
5204 -- Inspect and process a single action list of an if expression for
5205 -- transient controlled objects. If such objects are found, the routine
5206 -- generates code to clean them up when the context of the expression is
5207 -- evaluated or elaborated.
5209 ---------------------
5210 -- Process_Actions --
5211 ---------------------
5213 procedure Process_Actions
(Actions
: List_Id
) is
5217 Act
:= First
(Actions
);
5218 while Present
(Act
) loop
5219 if Nkind
(Act
) = N_Object_Declaration
5220 and then Is_Finalizable_Transient
(Act
, N
)
5222 Process_Transient_Object
(Act
, N
);
5227 end Process_Actions
;
5231 Loc
: constant Source_Ptr
:= Sloc
(N
);
5232 Cond
: constant Node_Id
:= First
(Expressions
(N
));
5233 Thenx
: constant Node_Id
:= Next
(Cond
);
5234 Elsex
: constant Node_Id
:= Next
(Thenx
);
5235 Typ
: constant Entity_Id
:= Etype
(N
);
5243 Ptr_Typ
: Entity_Id
;
5245 -- Start of processing for Expand_N_If_Expression
5248 -- Check for MINIMIZED/ELIMINATED overflow mode
5250 if Minimized_Eliminated_Overflow_Check
(N
) then
5251 Apply_Arithmetic_Overflow_Check
(N
);
5255 -- Fold at compile time if condition known. We have already folded
5256 -- static if expressions, but it is possible to fold any case in which
5257 -- the condition is known at compile time, even though the result is
5260 -- Note that we don't do the fold of such cases in Sem_Elab because
5261 -- it can cause infinite loops with the expander adding a conditional
5262 -- expression, and Sem_Elab circuitry removing it repeatedly.
5264 if Compile_Time_Known_Value
(Cond
) then
5265 if Is_True
(Expr_Value
(Cond
)) then
5267 Actions
:= Then_Actions
(N
);
5270 Actions
:= Else_Actions
(N
);
5275 if Present
(Actions
) then
5277 Make_Expression_With_Actions
(Loc
,
5278 Expression
=> Relocate_Node
(Expr
),
5279 Actions
=> Actions
));
5280 Analyze_And_Resolve
(N
, Typ
);
5282 Rewrite
(N
, Relocate_Node
(Expr
));
5285 -- Note that the result is never static (legitimate cases of static
5286 -- if expressions were folded in Sem_Eval).
5288 Set_Is_Static_Expression
(N
, False);
5292 -- If the type is limited, and the back end does not handle limited
5293 -- types, then we expand as follows to avoid the possibility of
5294 -- improper copying.
5296 -- type Ptr is access all Typ;
5300 -- Cnn := then-expr'Unrestricted_Access;
5303 -- Cnn := else-expr'Unrestricted_Access;
5306 -- and replace the if expression by a reference to Cnn.all.
5308 -- This special case can be skipped if the back end handles limited
5309 -- types properly and ensures that no incorrect copies are made.
5311 if Is_By_Reference_Type
(Typ
)
5312 and then not Back_End_Handles_Limited_Types
5314 -- When the "then" or "else" expressions involve controlled function
5315 -- calls, generated temporaries are chained on the corresponding list
5316 -- of actions. These temporaries need to be finalized after the if
5317 -- expression is evaluated.
5319 Process_Actions
(Then_Actions
(N
));
5320 Process_Actions
(Else_Actions
(N
));
5323 -- type Ann is access all Typ;
5325 Ptr_Typ
:= Make_Temporary
(Loc
, 'A');
5328 Make_Full_Type_Declaration
(Loc
,
5329 Defining_Identifier
=> Ptr_Typ
,
5331 Make_Access_To_Object_Definition
(Loc
,
5332 All_Present
=> True,
5333 Subtype_Indication
=> New_Occurrence_Of
(Typ
, Loc
))));
5338 Cnn
:= Make_Temporary
(Loc
, 'C', N
);
5341 Make_Object_Declaration
(Loc
,
5342 Defining_Identifier
=> Cnn
,
5343 Object_Definition
=> New_Occurrence_Of
(Ptr_Typ
, Loc
));
5347 -- Cnn := <Thenx>'Unrestricted_Access;
5349 -- Cnn := <Elsex>'Unrestricted_Access;
5353 Make_Implicit_If_Statement
(N
,
5354 Condition
=> Relocate_Node
(Cond
),
5355 Then_Statements
=> New_List
(
5356 Make_Assignment_Statement
(Sloc
(Thenx
),
5357 Name
=> New_Occurrence_Of
(Cnn
, Sloc
(Thenx
)),
5359 Make_Attribute_Reference
(Loc
,
5360 Prefix
=> Relocate_Node
(Thenx
),
5361 Attribute_Name
=> Name_Unrestricted_Access
))),
5363 Else_Statements
=> New_List
(
5364 Make_Assignment_Statement
(Sloc
(Elsex
),
5365 Name
=> New_Occurrence_Of
(Cnn
, Sloc
(Elsex
)),
5367 Make_Attribute_Reference
(Loc
,
5368 Prefix
=> Relocate_Node
(Elsex
),
5369 Attribute_Name
=> Name_Unrestricted_Access
))));
5371 -- Preserve the original context for which the if statement is being
5372 -- generated. This is needed by the finalization machinery to prevent
5373 -- the premature finalization of controlled objects found within the
5376 Set_From_Conditional_Expression
(New_If
);
5379 Make_Explicit_Dereference
(Loc
,
5380 Prefix
=> New_Occurrence_Of
(Cnn
, Loc
));
5382 -- If the result is an unconstrained array and the if expression is in a
5383 -- context other than the initializing expression of the declaration of
5384 -- an object, then we pull out the if expression as follows:
5386 -- Cnn : constant typ := if-expression
5388 -- and then replace the if expression with an occurrence of Cnn. This
5389 -- avoids the need in the back end to create on-the-fly variable length
5390 -- temporaries (which it cannot do!)
5392 -- Note that the test for being in an object declaration avoids doing an
5393 -- unnecessary expansion, and also avoids infinite recursion.
5395 elsif Is_Array_Type
(Typ
) and then not Is_Constrained
(Typ
)
5396 and then (Nkind
(Parent
(N
)) /= N_Object_Declaration
5397 or else Expression
(Parent
(N
)) /= N
)
5400 Cnn
: constant Node_Id
:= Make_Temporary
(Loc
, 'C', N
);
5403 Make_Object_Declaration
(Loc
,
5404 Defining_Identifier
=> Cnn
,
5405 Constant_Present
=> True,
5406 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
),
5407 Expression
=> Relocate_Node
(N
),
5408 Has_Init_Expression
=> True));
5410 Rewrite
(N
, New_Occurrence_Of
(Cnn
, Loc
));
5414 -- For other types, we only need to expand if there are other actions
5415 -- associated with either branch.
5417 elsif Present
(Then_Actions
(N
)) or else Present
(Else_Actions
(N
)) then
5419 -- We now wrap the actions into the appropriate expression
5421 if Present
(Then_Actions
(N
)) then
5423 Make_Expression_With_Actions
(Sloc
(Thenx
),
5424 Actions
=> Then_Actions
(N
),
5425 Expression
=> Relocate_Node
(Thenx
)));
5427 Set_Then_Actions
(N
, No_List
);
5428 Analyze_And_Resolve
(Thenx
, Typ
);
5431 if Present
(Else_Actions
(N
)) then
5433 Make_Expression_With_Actions
(Sloc
(Elsex
),
5434 Actions
=> Else_Actions
(N
),
5435 Expression
=> Relocate_Node
(Elsex
)));
5437 Set_Else_Actions
(N
, No_List
);
5438 Analyze_And_Resolve
(Elsex
, Typ
);
5443 -- If no actions then no expansion needed, gigi will handle it using the
5444 -- same approach as a C conditional expression.
5450 -- Fall through here for either the limited expansion, or the case of
5451 -- inserting actions for non-limited types. In both these cases, we must
5452 -- move the SLOC of the parent If statement to the newly created one and
5453 -- change it to the SLOC of the expression which, after expansion, will
5454 -- correspond to what is being evaluated.
5456 if Present
(Parent
(N
)) and then Nkind
(Parent
(N
)) = N_If_Statement
then
5457 Set_Sloc
(New_If
, Sloc
(Parent
(N
)));
5458 Set_Sloc
(Parent
(N
), Loc
);
5461 -- Make sure Then_Actions and Else_Actions are appropriately moved
5462 -- to the new if statement.
5464 if Present
(Then_Actions
(N
)) then
5466 (First
(Then_Statements
(New_If
)), Then_Actions
(N
));
5469 if Present
(Else_Actions
(N
)) then
5471 (First
(Else_Statements
(New_If
)), Else_Actions
(N
));
5474 Insert_Action
(N
, Decl
);
5475 Insert_Action
(N
, New_If
);
5477 Analyze_And_Resolve
(N
, Typ
);
5478 end Expand_N_If_Expression
;
5484 procedure Expand_N_In
(N
: Node_Id
) is
5485 Loc
: constant Source_Ptr
:= Sloc
(N
);
5486 Restyp
: constant Entity_Id
:= Etype
(N
);
5487 Lop
: constant Node_Id
:= Left_Opnd
(N
);
5488 Rop
: constant Node_Id
:= Right_Opnd
(N
);
5489 Static
: constant Boolean := Is_OK_Static_Expression
(N
);
5494 procedure Substitute_Valid_Check
;
5495 -- Replaces node N by Lop'Valid. This is done when we have an explicit
5496 -- test for the left operand being in range of its subtype.
5498 ----------------------------
5499 -- Substitute_Valid_Check --
5500 ----------------------------
5502 procedure Substitute_Valid_Check
is
5505 Make_Attribute_Reference
(Loc
,
5506 Prefix
=> Relocate_Node
(Lop
),
5507 Attribute_Name
=> Name_Valid
));
5509 Analyze_And_Resolve
(N
, Restyp
);
5511 -- Give warning unless overflow checking is MINIMIZED or ELIMINATED,
5512 -- in which case, this usage makes sense, and in any case, we have
5513 -- actually eliminated the danger of optimization above.
5515 if Overflow_Check_Mode
not in Minimized_Or_Eliminated
then
5517 ("??explicit membership test may be optimized away", N
);
5518 Error_Msg_N
-- CODEFIX
5519 ("\??use ''Valid attribute instead", N
);
5523 end Substitute_Valid_Check
;
5525 -- Start of processing for Expand_N_In
5528 -- If set membership case, expand with separate procedure
5530 if Present
(Alternatives
(N
)) then
5531 Expand_Set_Membership
(N
);
5535 -- Not set membership, proceed with expansion
5537 Ltyp
:= Etype
(Left_Opnd
(N
));
5538 Rtyp
:= Etype
(Right_Opnd
(N
));
5540 -- If MINIMIZED/ELIMINATED overflow mode and type is a signed integer
5541 -- type, then expand with a separate procedure. Note the use of the
5542 -- flag No_Minimize_Eliminate to prevent infinite recursion.
5544 if Overflow_Check_Mode
in Minimized_Or_Eliminated
5545 and then Is_Signed_Integer_Type
(Ltyp
)
5546 and then not No_Minimize_Eliminate
(N
)
5548 Expand_Membership_Minimize_Eliminate_Overflow
(N
);
5552 -- Check case of explicit test for an expression in range of its
5553 -- subtype. This is suspicious usage and we replace it with a 'Valid
5554 -- test and give a warning for scalar types.
5556 if Is_Scalar_Type
(Ltyp
)
5558 -- Only relevant for source comparisons
5560 and then Comes_From_Source
(N
)
5562 -- In floating-point this is a standard way to check for finite values
5563 -- and using 'Valid would typically be a pessimization.
5565 and then not Is_Floating_Point_Type
(Ltyp
)
5567 -- Don't give the message unless right operand is a type entity and
5568 -- the type of the left operand matches this type. Note that this
5569 -- eliminates the cases where MINIMIZED/ELIMINATED mode overflow
5570 -- checks have changed the type of the left operand.
5572 and then Nkind
(Rop
) in N_Has_Entity
5573 and then Ltyp
= Entity
(Rop
)
5575 -- Skip in VM mode, where we have no sense of invalid values. The
5576 -- warning still seems relevant, but not important enough to worry.
5578 and then VM_Target
= No_VM
5580 -- Skip this for predicated types, where such expressions are a
5581 -- reasonable way of testing if something meets the predicate.
5583 and then not Present
(Predicate_Function
(Ltyp
))
5585 Substitute_Valid_Check
;
5589 -- Do validity check on operands
5591 if Validity_Checks_On
and Validity_Check_Operands
then
5592 Ensure_Valid
(Left_Opnd
(N
));
5593 Validity_Check_Range
(Right_Opnd
(N
));
5596 -- Case of explicit range
5598 if Nkind
(Rop
) = N_Range
then
5600 Lo
: constant Node_Id
:= Low_Bound
(Rop
);
5601 Hi
: constant Node_Id
:= High_Bound
(Rop
);
5603 Lo_Orig
: constant Node_Id
:= Original_Node
(Lo
);
5604 Hi_Orig
: constant Node_Id
:= Original_Node
(Hi
);
5606 Lcheck
: Compare_Result
;
5607 Ucheck
: Compare_Result
;
5609 Warn1
: constant Boolean :=
5610 Constant_Condition_Warnings
5611 and then Comes_From_Source
(N
)
5612 and then not In_Instance
;
5613 -- This must be true for any of the optimization warnings, we
5614 -- clearly want to give them only for source with the flag on. We
5615 -- also skip these warnings in an instance since it may be the
5616 -- case that different instantiations have different ranges.
5618 Warn2
: constant Boolean :=
5620 and then Nkind
(Original_Node
(Rop
)) = N_Range
5621 and then Is_Integer_Type
(Etype
(Lo
));
5622 -- For the case where only one bound warning is elided, we also
5623 -- insist on an explicit range and an integer type. The reason is
5624 -- that the use of enumeration ranges including an end point is
5625 -- common, as is the use of a subtype name, one of whose bounds is
5626 -- the same as the type of the expression.
5629 -- If test is explicit x'First .. x'Last, replace by valid check
5631 -- Could use some individual comments for this complex test ???
5633 if Is_Scalar_Type
(Ltyp
)
5635 -- And left operand is X'First where X matches left operand
5636 -- type (this eliminates cases of type mismatch, including
5637 -- the cases where ELIMINATED/MINIMIZED mode has changed the
5638 -- type of the left operand.
5640 and then Nkind
(Lo_Orig
) = N_Attribute_Reference
5641 and then Attribute_Name
(Lo_Orig
) = Name_First
5642 and then Nkind
(Prefix
(Lo_Orig
)) in N_Has_Entity
5643 and then Entity
(Prefix
(Lo_Orig
)) = Ltyp
5645 -- Same tests for right operand
5647 and then Nkind
(Hi_Orig
) = N_Attribute_Reference
5648 and then Attribute_Name
(Hi_Orig
) = Name_Last
5649 and then Nkind
(Prefix
(Hi_Orig
)) in N_Has_Entity
5650 and then Entity
(Prefix
(Hi_Orig
)) = Ltyp
5652 -- Relevant only for source cases
5654 and then Comes_From_Source
(N
)
5656 -- Omit for VM cases, where we don't have invalid values
5658 and then VM_Target
= No_VM
5660 Substitute_Valid_Check
;
5664 -- If bounds of type are known at compile time, and the end points
5665 -- are known at compile time and identical, this is another case
5666 -- for substituting a valid test. We only do this for discrete
5667 -- types, since it won't arise in practice for float types.
5669 if Comes_From_Source
(N
)
5670 and then Is_Discrete_Type
(Ltyp
)
5671 and then Compile_Time_Known_Value
(Type_High_Bound
(Ltyp
))
5672 and then Compile_Time_Known_Value
(Type_Low_Bound
(Ltyp
))
5673 and then Compile_Time_Known_Value
(Lo
)
5674 and then Compile_Time_Known_Value
(Hi
)
5675 and then Expr_Value
(Type_High_Bound
(Ltyp
)) = Expr_Value
(Hi
)
5676 and then Expr_Value
(Type_Low_Bound
(Ltyp
)) = Expr_Value
(Lo
)
5678 -- Kill warnings in instances, since they may be cases where we
5679 -- have a test in the generic that makes sense with some types
5680 -- and not with other types.
5682 and then not In_Instance
5684 Substitute_Valid_Check
;
5688 -- If we have an explicit range, do a bit of optimization based on
5689 -- range analysis (we may be able to kill one or both checks).
5691 Lcheck
:= Compile_Time_Compare
(Lop
, Lo
, Assume_Valid
=> False);
5692 Ucheck
:= Compile_Time_Compare
(Lop
, Hi
, Assume_Valid
=> False);
5694 -- If either check is known to fail, replace result by False since
5695 -- the other check does not matter. Preserve the static flag for
5696 -- legality checks, because we are constant-folding beyond RM 4.9.
5698 if Lcheck
= LT
or else Ucheck
= GT
then
5700 Error_Msg_N
("?c?range test optimized away", N
);
5701 Error_Msg_N
("\?c?value is known to be out of range", N
);
5704 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
5705 Analyze_And_Resolve
(N
, Restyp
);
5706 Set_Is_Static_Expression
(N
, Static
);
5709 -- If both checks are known to succeed, replace result by True,
5710 -- since we know we are in range.
5712 elsif Lcheck
in Compare_GE
and then Ucheck
in Compare_LE
then
5714 Error_Msg_N
("?c?range test optimized away", N
);
5715 Error_Msg_N
("\?c?value is known to be in range", N
);
5718 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
5719 Analyze_And_Resolve
(N
, Restyp
);
5720 Set_Is_Static_Expression
(N
, Static
);
5723 -- If lower bound check succeeds and upper bound check is not
5724 -- known to succeed or fail, then replace the range check with
5725 -- a comparison against the upper bound.
5727 elsif Lcheck
in Compare_GE
then
5728 if Warn2
and then not In_Instance
then
5729 Error_Msg_N
("??lower bound test optimized away", Lo
);
5730 Error_Msg_N
("\??value is known to be in range", Lo
);
5736 Right_Opnd
=> High_Bound
(Rop
)));
5737 Analyze_And_Resolve
(N
, Restyp
);
5740 -- If upper bound check succeeds and lower bound check is not
5741 -- known to succeed or fail, then replace the range check with
5742 -- a comparison against the lower bound.
5744 elsif Ucheck
in Compare_LE
then
5745 if Warn2
and then not In_Instance
then
5746 Error_Msg_N
("??upper bound test optimized away", Hi
);
5747 Error_Msg_N
("\??value is known to be in range", Hi
);
5753 Right_Opnd
=> Low_Bound
(Rop
)));
5754 Analyze_And_Resolve
(N
, Restyp
);
5758 -- We couldn't optimize away the range check, but there is one
5759 -- more issue. If we are checking constant conditionals, then we
5760 -- see if we can determine the outcome assuming everything is
5761 -- valid, and if so give an appropriate warning.
5763 if Warn1
and then not Assume_No_Invalid_Values
then
5764 Lcheck
:= Compile_Time_Compare
(Lop
, Lo
, Assume_Valid
=> True);
5765 Ucheck
:= Compile_Time_Compare
(Lop
, Hi
, Assume_Valid
=> True);
5767 -- Result is out of range for valid value
5769 if Lcheck
= LT
or else Ucheck
= GT
then
5771 ("?c?value can only be in range if it is invalid", N
);
5773 -- Result is in range for valid value
5775 elsif Lcheck
in Compare_GE
and then Ucheck
in Compare_LE
then
5777 ("?c?value can only be out of range if it is invalid", N
);
5779 -- Lower bound check succeeds if value is valid
5781 elsif Warn2
and then Lcheck
in Compare_GE
then
5783 ("?c?lower bound check only fails if it is invalid", Lo
);
5785 -- Upper bound check succeeds if value is valid
5787 elsif Warn2
and then Ucheck
in Compare_LE
then
5789 ("?c?upper bound check only fails for invalid values", Hi
);
5794 -- For all other cases of an explicit range, nothing to be done
5798 -- Here right operand is a subtype mark
5802 Typ
: Entity_Id
:= Etype
(Rop
);
5803 Is_Acc
: constant Boolean := Is_Access_Type
(Typ
);
5804 Cond
: Node_Id
:= Empty
;
5806 Obj
: Node_Id
:= Lop
;
5807 SCIL_Node
: Node_Id
;
5810 Remove_Side_Effects
(Obj
);
5812 -- For tagged type, do tagged membership operation
5814 if Is_Tagged_Type
(Typ
) then
5816 -- No expansion will be performed when VM_Target, as the VM
5817 -- back-ends will handle the membership tests directly (tags
5818 -- are not explicitly represented in Java objects, so the
5819 -- normal tagged membership expansion is not what we want).
5821 if Tagged_Type_Expansion
then
5822 Tagged_Membership
(N
, SCIL_Node
, New_N
);
5824 Analyze_And_Resolve
(N
, Restyp
);
5826 -- Update decoration of relocated node referenced by the
5829 if Generate_SCIL
and then Present
(SCIL_Node
) then
5830 Set_SCIL_Node
(N
, SCIL_Node
);
5836 -- If type is scalar type, rewrite as x in t'First .. t'Last.
5837 -- This reason we do this is that the bounds may have the wrong
5838 -- type if they come from the original type definition. Also this
5839 -- way we get all the processing above for an explicit range.
5841 -- Don't do this for predicated types, since in this case we
5842 -- want to check the predicate.
5844 elsif Is_Scalar_Type
(Typ
) then
5845 if No
(Predicate_Function
(Typ
)) then
5849 Make_Attribute_Reference
(Loc
,
5850 Attribute_Name
=> Name_First
,
5851 Prefix
=> New_Occurrence_Of
(Typ
, Loc
)),
5854 Make_Attribute_Reference
(Loc
,
5855 Attribute_Name
=> Name_Last
,
5856 Prefix
=> New_Occurrence_Of
(Typ
, Loc
))));
5857 Analyze_And_Resolve
(N
, Restyp
);
5862 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
5863 -- a membership test if the subtype mark denotes a constrained
5864 -- Unchecked_Union subtype and the expression lacks inferable
5867 elsif Is_Unchecked_Union
(Base_Type
(Typ
))
5868 and then Is_Constrained
(Typ
)
5869 and then not Has_Inferable_Discriminants
(Lop
)
5872 Make_Raise_Program_Error
(Loc
,
5873 Reason
=> PE_Unchecked_Union_Restriction
));
5875 -- Prevent Gigi from generating incorrect code by rewriting the
5876 -- test as False. What is this undocumented thing about ???
5878 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
5882 -- Here we have a non-scalar type
5885 Typ
:= Designated_Type
(Typ
);
5888 if not Is_Constrained
(Typ
) then
5889 Rewrite
(N
, New_Occurrence_Of
(Standard_True
, Loc
));
5890 Analyze_And_Resolve
(N
, Restyp
);
5892 -- For the constrained array case, we have to check the subscripts
5893 -- for an exact match if the lengths are non-zero (the lengths
5894 -- must match in any case).
5896 elsif Is_Array_Type
(Typ
) then
5897 Check_Subscripts
: declare
5898 function Build_Attribute_Reference
5901 Dim
: Nat
) return Node_Id
;
5902 -- Build attribute reference E'Nam (Dim)
5904 -------------------------------
5905 -- Build_Attribute_Reference --
5906 -------------------------------
5908 function Build_Attribute_Reference
5911 Dim
: Nat
) return Node_Id
5915 Make_Attribute_Reference
(Loc
,
5917 Attribute_Name
=> Nam
,
5918 Expressions
=> New_List
(
5919 Make_Integer_Literal
(Loc
, Dim
)));
5920 end Build_Attribute_Reference
;
5922 -- Start of processing for Check_Subscripts
5925 for J
in 1 .. Number_Dimensions
(Typ
) loop
5926 Evolve_And_Then
(Cond
,
5929 Build_Attribute_Reference
5930 (Duplicate_Subexpr_No_Checks
(Obj
),
5933 Build_Attribute_Reference
5934 (New_Occurrence_Of
(Typ
, Loc
), Name_First
, J
)));
5936 Evolve_And_Then
(Cond
,
5939 Build_Attribute_Reference
5940 (Duplicate_Subexpr_No_Checks
(Obj
),
5943 Build_Attribute_Reference
5944 (New_Occurrence_Of
(Typ
, Loc
), Name_Last
, J
)));
5953 Right_Opnd
=> Make_Null
(Loc
)),
5954 Right_Opnd
=> Cond
);
5958 Analyze_And_Resolve
(N
, Restyp
);
5959 end Check_Subscripts
;
5961 -- These are the cases where constraint checks may be required,
5962 -- e.g. records with possible discriminants
5965 -- Expand the test into a series of discriminant comparisons.
5966 -- The expression that is built is the negation of the one that
5967 -- is used for checking discriminant constraints.
5969 Obj
:= Relocate_Node
(Left_Opnd
(N
));
5971 if Has_Discriminants
(Typ
) then
5972 Cond
:= Make_Op_Not
(Loc
,
5973 Right_Opnd
=> Build_Discriminant_Checks
(Obj
, Typ
));
5976 Cond
:= Make_Or_Else
(Loc
,
5980 Right_Opnd
=> Make_Null
(Loc
)),
5981 Right_Opnd
=> Cond
);
5985 Cond
:= New_Occurrence_Of
(Standard_True
, Loc
);
5989 Analyze_And_Resolve
(N
, Restyp
);
5992 -- Ada 2012 (AI05-0149): Handle membership tests applied to an
5993 -- expression of an anonymous access type. This can involve an
5994 -- accessibility test and a tagged type membership test in the
5995 -- case of tagged designated types.
5997 if Ada_Version
>= Ada_2012
5999 and then Ekind
(Ltyp
) = E_Anonymous_Access_Type
6002 Expr_Entity
: Entity_Id
:= Empty
;
6004 Param_Level
: Node_Id
;
6005 Type_Level
: Node_Id
;
6008 if Is_Entity_Name
(Lop
) then
6009 Expr_Entity
:= Param_Entity
(Lop
);
6011 if not Present
(Expr_Entity
) then
6012 Expr_Entity
:= Entity
(Lop
);
6016 -- If a conversion of the anonymous access value to the
6017 -- tested type would be illegal, then the result is False.
6019 if not Valid_Conversion
6020 (Lop
, Rtyp
, Lop
, Report_Errs
=> False)
6022 Rewrite
(N
, New_Occurrence_Of
(Standard_False
, Loc
));
6023 Analyze_And_Resolve
(N
, Restyp
);
6025 -- Apply an accessibility check if the access object has an
6026 -- associated access level and when the level of the type is
6027 -- less deep than the level of the access parameter. This
6028 -- only occur for access parameters and stand-alone objects
6029 -- of an anonymous access type.
6032 if Present
(Expr_Entity
)
6035 (Effective_Extra_Accessibility
(Expr_Entity
))
6036 and then UI_Gt
(Object_Access_Level
(Lop
),
6037 Type_Access_Level
(Rtyp
))
6041 (Effective_Extra_Accessibility
(Expr_Entity
), Loc
);
6044 Make_Integer_Literal
(Loc
, Type_Access_Level
(Rtyp
));
6046 -- Return True only if the accessibility level of the
6047 -- expression entity is not deeper than the level of
6048 -- the tested access type.
6052 Left_Opnd
=> Relocate_Node
(N
),
6053 Right_Opnd
=> Make_Op_Le
(Loc
,
6054 Left_Opnd
=> Param_Level
,
6055 Right_Opnd
=> Type_Level
)));
6057 Analyze_And_Resolve
(N
);
6060 -- If the designated type is tagged, do tagged membership
6063 -- *** NOTE: we have to check not null before doing the
6064 -- tagged membership test (but maybe that can be done
6065 -- inside Tagged_Membership?).
6067 if Is_Tagged_Type
(Typ
) then
6070 Left_Opnd
=> Relocate_Node
(N
),
6074 Right_Opnd
=> Make_Null
(Loc
))));
6076 -- No expansion will be performed when VM_Target, as
6077 -- the VM back-ends will handle the membership tests
6078 -- directly (tags are not explicitly represented in
6079 -- Java objects, so the normal tagged membership
6080 -- expansion is not what we want).
6082 if Tagged_Type_Expansion
then
6084 -- Note that we have to pass Original_Node, because
6085 -- the membership test might already have been
6086 -- rewritten by earlier parts of membership test.
6089 (Original_Node
(N
), SCIL_Node
, New_N
);
6091 -- Update decoration of relocated node referenced
6092 -- by the SCIL node.
6094 if Generate_SCIL
and then Present
(SCIL_Node
) then
6095 Set_SCIL_Node
(New_N
, SCIL_Node
);
6100 Left_Opnd
=> Relocate_Node
(N
),
6101 Right_Opnd
=> New_N
));
6103 Analyze_And_Resolve
(N
, Restyp
);
6112 -- At this point, we have done the processing required for the basic
6113 -- membership test, but not yet dealt with the predicate.
6117 -- If a predicate is present, then we do the predicate test, but we
6118 -- most certainly want to omit this if we are within the predicate
6119 -- function itself, since otherwise we have an infinite recursion.
6120 -- The check should also not be emitted when testing against a range
6121 -- (the check is only done when the right operand is a subtype; see
6122 -- RM12-4.5.2 (28.1/3-30/3)).
6125 PFunc
: constant Entity_Id
:= Predicate_Function
(Rtyp
);
6129 and then Current_Scope
/= PFunc
6130 and then Nkind
(Rop
) /= N_Range
6134 Left_Opnd
=> Relocate_Node
(N
),
6135 Right_Opnd
=> Make_Predicate_Call
(Rtyp
, Lop
, Mem
=> True)));
6137 -- Analyze new expression, mark left operand as analyzed to
6138 -- avoid infinite recursion adding predicate calls. Similarly,
6139 -- suppress further range checks on the call.
6141 Set_Analyzed
(Left_Opnd
(N
));
6142 Analyze_And_Resolve
(N
, Standard_Boolean
, Suppress
=> All_Checks
);
6144 -- All done, skip attempt at compile time determination of result
6151 --------------------------------
6152 -- Expand_N_Indexed_Component --
6153 --------------------------------
6155 procedure Expand_N_Indexed_Component
(N
: Node_Id
) is
6156 Loc
: constant Source_Ptr
:= Sloc
(N
);
6157 Typ
: constant Entity_Id
:= Etype
(N
);
6158 P
: constant Node_Id
:= Prefix
(N
);
6159 T
: constant Entity_Id
:= Etype
(P
);
6163 -- A special optimization, if we have an indexed component that is
6164 -- selecting from a slice, then we can eliminate the slice, since, for
6165 -- example, x (i .. j)(k) is identical to x(k). The only difference is
6166 -- the range check required by the slice. The range check for the slice
6167 -- itself has already been generated. The range check for the
6168 -- subscripting operation is ensured by converting the subject to
6169 -- the subtype of the slice.
6171 -- This optimization not only generates better code, avoiding slice
6172 -- messing especially in the packed case, but more importantly bypasses
6173 -- some problems in handling this peculiar case, for example, the issue
6174 -- of dealing specially with object renamings.
6176 if Nkind
(P
) = N_Slice
6178 -- This optimization is disabled for CodePeer because it can transform
6179 -- an index-check constraint_error into a range-check constraint_error
6180 -- and CodePeer cares about that distinction.
6182 and then not CodePeer_Mode
6185 Make_Indexed_Component
(Loc
,
6186 Prefix
=> Prefix
(P
),
6187 Expressions
=> New_List
(
6189 (Etype
(First_Index
(Etype
(P
))),
6190 First
(Expressions
(N
))))));
6191 Analyze_And_Resolve
(N
, Typ
);
6195 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
6196 -- function, then additional actuals must be passed.
6198 if Ada_Version
>= Ada_2005
6199 and then Is_Build_In_Place_Function_Call
(P
)
6201 Make_Build_In_Place_Call_In_Anonymous_Context
(P
);
6204 -- If the prefix is an access type, then we unconditionally rewrite if
6205 -- as an explicit dereference. This simplifies processing for several
6206 -- cases, including packed array cases and certain cases in which checks
6207 -- must be generated. We used to try to do this only when it was
6208 -- necessary, but it cleans up the code to do it all the time.
6210 if Is_Access_Type
(T
) then
6211 Insert_Explicit_Dereference
(P
);
6212 Analyze_And_Resolve
(P
, Designated_Type
(T
));
6213 Atp
:= Designated_Type
(T
);
6218 -- Generate index and validity checks
6220 Generate_Index_Checks
(N
);
6222 if Validity_Checks_On
and then Validity_Check_Subscripts
then
6223 Apply_Subscript_Validity_Checks
(N
);
6226 -- If selecting from an array with atomic components, and atomic sync
6227 -- is not suppressed for this array type, set atomic sync flag.
6229 if (Has_Atomic_Components
(Atp
)
6230 and then not Atomic_Synchronization_Disabled
(Atp
))
6231 or else (Is_Atomic
(Typ
)
6232 and then not Atomic_Synchronization_Disabled
(Typ
))
6234 Activate_Atomic_Synchronization
(N
);
6237 -- All done for the non-packed case
6239 if not Is_Packed
(Etype
(Prefix
(N
))) then
6243 -- For packed arrays that are not bit-packed (i.e. the case of an array
6244 -- with one or more index types with a non-contiguous enumeration type),
6245 -- we can always use the normal packed element get circuit.
6247 if not Is_Bit_Packed_Array
(Etype
(Prefix
(N
))) then
6248 Expand_Packed_Element_Reference
(N
);
6252 -- For a reference to a component of a bit packed array, we convert it
6253 -- to a reference to the corresponding Packed_Array_Impl_Type. We only
6254 -- want to do this for simple references, and not for:
6256 -- Left side of assignment, or prefix of left side of assignment, or
6257 -- prefix of the prefix, to handle packed arrays of packed arrays,
6258 -- This case is handled in Exp_Ch5.Expand_N_Assignment_Statement
6260 -- Renaming objects in renaming associations
6261 -- This case is handled when a use of the renamed variable occurs
6263 -- Actual parameters for a procedure call
6264 -- This case is handled in Exp_Ch6.Expand_Actuals
6266 -- The second expression in a 'Read attribute reference
6268 -- The prefix of an address or bit or size attribute reference
6270 -- The following circuit detects these exceptions
6273 Child
: Node_Id
:= N
;
6274 Parnt
: Node_Id
:= Parent
(N
);
6278 if Nkind
(Parnt
) = N_Unchecked_Expression
then
6281 elsif Nkind_In
(Parnt
, N_Object_Renaming_Declaration
,
6282 N_Procedure_Call_Statement
)
6283 or else (Nkind
(Parnt
) = N_Parameter_Association
6285 Nkind
(Parent
(Parnt
)) = N_Procedure_Call_Statement
)
6289 elsif Nkind
(Parnt
) = N_Attribute_Reference
6290 and then Nam_In
(Attribute_Name
(Parnt
), Name_Address
,
6293 and then Prefix
(Parnt
) = Child
6297 elsif Nkind
(Parnt
) = N_Assignment_Statement
6298 and then Name
(Parnt
) = Child
6302 -- If the expression is an index of an indexed component, it must
6303 -- be expanded regardless of context.
6305 elsif Nkind
(Parnt
) = N_Indexed_Component
6306 and then Child
/= Prefix
(Parnt
)
6308 Expand_Packed_Element_Reference
(N
);
6311 elsif Nkind
(Parent
(Parnt
)) = N_Assignment_Statement
6312 and then Name
(Parent
(Parnt
)) = Parnt
6316 elsif Nkind
(Parnt
) = N_Attribute_Reference
6317 and then Attribute_Name
(Parnt
) = Name_Read
6318 and then Next
(First
(Expressions
(Parnt
))) = Child
6322 elsif Nkind_In
(Parnt
, N_Indexed_Component
, N_Selected_Component
)
6323 and then Prefix
(Parnt
) = Child
6328 Expand_Packed_Element_Reference
(N
);
6332 -- Keep looking up tree for unchecked expression, or if we are the
6333 -- prefix of a possible assignment left side.
6336 Parnt
:= Parent
(Child
);
6339 end Expand_N_Indexed_Component
;
6341 ---------------------
6342 -- Expand_N_Not_In --
6343 ---------------------
6345 -- Replace a not in b by not (a in b) so that the expansions for (a in b)
6346 -- can be done. This avoids needing to duplicate this expansion code.
6348 procedure Expand_N_Not_In
(N
: Node_Id
) is
6349 Loc
: constant Source_Ptr
:= Sloc
(N
);
6350 Typ
: constant Entity_Id
:= Etype
(N
);
6351 Cfs
: constant Boolean := Comes_From_Source
(N
);
6358 Left_Opnd
=> Left_Opnd
(N
),
6359 Right_Opnd
=> Right_Opnd
(N
))));
6361 -- If this is a set membership, preserve list of alternatives
6363 Set_Alternatives
(Right_Opnd
(N
), Alternatives
(Original_Node
(N
)));
6365 -- We want this to appear as coming from source if original does (see
6366 -- transformations in Expand_N_In).
6368 Set_Comes_From_Source
(N
, Cfs
);
6369 Set_Comes_From_Source
(Right_Opnd
(N
), Cfs
);
6371 -- Now analyze transformed node
6373 Analyze_And_Resolve
(N
, Typ
);
6374 end Expand_N_Not_In
;
6380 -- The only replacement required is for the case of a null of a type that
6381 -- is an access to protected subprogram, or a subtype thereof. We represent
6382 -- such access values as a record, and so we must replace the occurrence of
6383 -- null by the equivalent record (with a null address and a null pointer in
6384 -- it), so that the backend creates the proper value.
6386 procedure Expand_N_Null
(N
: Node_Id
) is
6387 Loc
: constant Source_Ptr
:= Sloc
(N
);
6388 Typ
: constant Entity_Id
:= Base_Type
(Etype
(N
));
6392 if Is_Access_Protected_Subprogram_Type
(Typ
) then
6394 Make_Aggregate
(Loc
,
6395 Expressions
=> New_List
(
6396 New_Occurrence_Of
(RTE
(RE_Null_Address
), Loc
),
6400 Analyze_And_Resolve
(N
, Equivalent_Type
(Typ
));
6402 -- For subsequent semantic analysis, the node must retain its type.
6403 -- Gigi in any case replaces this type by the corresponding record
6404 -- type before processing the node.
6410 when RE_Not_Available
=>
6414 ---------------------
6415 -- Expand_N_Op_Abs --
6416 ---------------------
6418 procedure Expand_N_Op_Abs
(N
: Node_Id
) is
6419 Loc
: constant Source_Ptr
:= Sloc
(N
);
6420 Expr
: constant Node_Id
:= Right_Opnd
(N
);
6423 Unary_Op_Validity_Checks
(N
);
6425 -- Check for MINIMIZED/ELIMINATED overflow mode
6427 if Minimized_Eliminated_Overflow_Check
(N
) then
6428 Apply_Arithmetic_Overflow_Check
(N
);
6432 -- Deal with software overflow checking
6434 if not Backend_Overflow_Checks_On_Target
6435 and then Is_Signed_Integer_Type
(Etype
(N
))
6436 and then Do_Overflow_Check
(N
)
6438 -- The only case to worry about is when the argument is equal to the
6439 -- largest negative number, so what we do is to insert the check:
6441 -- [constraint_error when Expr = typ'Base'First]
6443 -- with the usual Duplicate_Subexpr use coding for expr
6446 Make_Raise_Constraint_Error
(Loc
,
6449 Left_Opnd
=> Duplicate_Subexpr
(Expr
),
6451 Make_Attribute_Reference
(Loc
,
6453 New_Occurrence_Of
(Base_Type
(Etype
(Expr
)), Loc
),
6454 Attribute_Name
=> Name_First
)),
6455 Reason
=> CE_Overflow_Check_Failed
));
6457 end Expand_N_Op_Abs
;
6459 ---------------------
6460 -- Expand_N_Op_Add --
6461 ---------------------
6463 procedure Expand_N_Op_Add
(N
: Node_Id
) is
6464 Typ
: constant Entity_Id
:= Etype
(N
);
6467 Binary_Op_Validity_Checks
(N
);
6469 -- Check for MINIMIZED/ELIMINATED overflow mode
6471 if Minimized_Eliminated_Overflow_Check
(N
) then
6472 Apply_Arithmetic_Overflow_Check
(N
);
6476 -- N + 0 = 0 + N = N for integer types
6478 if Is_Integer_Type
(Typ
) then
6479 if Compile_Time_Known_Value
(Right_Opnd
(N
))
6480 and then Expr_Value
(Right_Opnd
(N
)) = Uint_0
6482 Rewrite
(N
, Left_Opnd
(N
));
6485 elsif Compile_Time_Known_Value
(Left_Opnd
(N
))
6486 and then Expr_Value
(Left_Opnd
(N
)) = Uint_0
6488 Rewrite
(N
, Right_Opnd
(N
));
6493 -- Arithmetic overflow checks for signed integer/fixed point types
6495 if Is_Signed_Integer_Type
(Typ
) or else Is_Fixed_Point_Type
(Typ
) then
6496 Apply_Arithmetic_Overflow_Check
(N
);
6500 -- Overflow checks for floating-point if -gnateF mode active
6502 Check_Float_Op_Overflow
(N
);
6503 end Expand_N_Op_Add
;
6505 ---------------------
6506 -- Expand_N_Op_And --
6507 ---------------------
6509 procedure Expand_N_Op_And
(N
: Node_Id
) is
6510 Typ
: constant Entity_Id
:= Etype
(N
);
6513 Binary_Op_Validity_Checks
(N
);
6515 if Is_Array_Type
(Etype
(N
)) then
6516 Expand_Boolean_Operator
(N
);
6518 elsif Is_Boolean_Type
(Etype
(N
)) then
6519 Adjust_Condition
(Left_Opnd
(N
));
6520 Adjust_Condition
(Right_Opnd
(N
));
6521 Set_Etype
(N
, Standard_Boolean
);
6522 Adjust_Result_Type
(N
, Typ
);
6524 elsif Is_Intrinsic_Subprogram
(Entity
(N
)) then
6525 Expand_Intrinsic_Call
(N
, Entity
(N
));
6528 end Expand_N_Op_And
;
6530 ------------------------
6531 -- Expand_N_Op_Concat --
6532 ------------------------
6534 procedure Expand_N_Op_Concat
(N
: Node_Id
) is
6536 -- List of operands to be concatenated
6539 -- Node which is to be replaced by the result of concatenating the nodes
6540 -- in the list Opnds.
6543 -- Ensure validity of both operands
6545 Binary_Op_Validity_Checks
(N
);
6547 -- If we are the left operand of a concatenation higher up the tree,
6548 -- then do nothing for now, since we want to deal with a series of
6549 -- concatenations as a unit.
6551 if Nkind
(Parent
(N
)) = N_Op_Concat
6552 and then N
= Left_Opnd
(Parent
(N
))
6557 -- We get here with a concatenation whose left operand may be a
6558 -- concatenation itself with a consistent type. We need to process
6559 -- these concatenation operands from left to right, which means
6560 -- from the deepest node in the tree to the highest node.
6563 while Nkind
(Left_Opnd
(Cnode
)) = N_Op_Concat
loop
6564 Cnode
:= Left_Opnd
(Cnode
);
6567 -- Now Cnode is the deepest concatenation, and its parents are the
6568 -- concatenation nodes above, so now we process bottom up, doing the
6571 -- The outer loop runs more than once if more than one concatenation
6572 -- type is involved.
6575 Opnds
:= New_List
(Left_Opnd
(Cnode
), Right_Opnd
(Cnode
));
6576 Set_Parent
(Opnds
, N
);
6578 -- The inner loop gathers concatenation operands
6580 Inner
: while Cnode
/= N
6581 and then Base_Type
(Etype
(Cnode
)) =
6582 Base_Type
(Etype
(Parent
(Cnode
)))
6584 Cnode
:= Parent
(Cnode
);
6585 Append
(Right_Opnd
(Cnode
), Opnds
);
6588 Expand_Concatenate
(Cnode
, Opnds
);
6590 exit Outer
when Cnode
= N
;
6591 Cnode
:= Parent
(Cnode
);
6593 end Expand_N_Op_Concat
;
6595 ------------------------
6596 -- Expand_N_Op_Divide --
6597 ------------------------
6599 procedure Expand_N_Op_Divide
(N
: Node_Id
) is
6600 Loc
: constant Source_Ptr
:= Sloc
(N
);
6601 Lopnd
: constant Node_Id
:= Left_Opnd
(N
);
6602 Ropnd
: constant Node_Id
:= Right_Opnd
(N
);
6603 Ltyp
: constant Entity_Id
:= Etype
(Lopnd
);
6604 Rtyp
: constant Entity_Id
:= Etype
(Ropnd
);
6605 Typ
: Entity_Id
:= Etype
(N
);
6606 Rknow
: constant Boolean := Is_Integer_Type
(Typ
)
6608 Compile_Time_Known_Value
(Ropnd
);
6612 Binary_Op_Validity_Checks
(N
);
6614 -- Check for MINIMIZED/ELIMINATED overflow mode
6616 if Minimized_Eliminated_Overflow_Check
(N
) then
6617 Apply_Arithmetic_Overflow_Check
(N
);
6621 -- Otherwise proceed with expansion of division
6624 Rval
:= Expr_Value
(Ropnd
);
6627 -- N / 1 = N for integer types
6629 if Rknow
and then Rval
= Uint_1
then
6634 -- Convert x / 2 ** y to Shift_Right (x, y). Note that the fact that
6635 -- Is_Power_Of_2_For_Shift is set means that we know that our left
6636 -- operand is an unsigned integer, as required for this to work.
6638 if Nkind
(Ropnd
) = N_Op_Expon
6639 and then Is_Power_Of_2_For_Shift
(Ropnd
)
6641 -- We cannot do this transformation in configurable run time mode if we
6642 -- have 64-bit integers and long shifts are not available.
6644 and then (Esize
(Ltyp
) <= 32 or else Support_Long_Shifts_On_Target
)
6647 Make_Op_Shift_Right
(Loc
,
6650 Convert_To
(Standard_Natural
, Right_Opnd
(Ropnd
))));
6651 Analyze_And_Resolve
(N
, Typ
);
6655 -- Do required fixup of universal fixed operation
6657 if Typ
= Universal_Fixed
then
6658 Fixup_Universal_Fixed_Operation
(N
);
6662 -- Divisions with fixed-point results
6664 if Is_Fixed_Point_Type
(Typ
) then
6666 -- No special processing if Treat_Fixed_As_Integer is set, since
6667 -- from a semantic point of view such operations are simply integer
6668 -- operations and will be treated that way.
6670 if not Treat_Fixed_As_Integer
(N
) then
6671 if Is_Integer_Type
(Rtyp
) then
6672 Expand_Divide_Fixed_By_Integer_Giving_Fixed
(N
);
6674 Expand_Divide_Fixed_By_Fixed_Giving_Fixed
(N
);
6678 -- Other cases of division of fixed-point operands. Again we exclude the
6679 -- case where Treat_Fixed_As_Integer is set.
6681 elsif (Is_Fixed_Point_Type
(Ltyp
) or else Is_Fixed_Point_Type
(Rtyp
))
6682 and then not Treat_Fixed_As_Integer
(N
)
6684 if Is_Integer_Type
(Typ
) then
6685 Expand_Divide_Fixed_By_Fixed_Giving_Integer
(N
);
6687 pragma Assert
(Is_Floating_Point_Type
(Typ
));
6688 Expand_Divide_Fixed_By_Fixed_Giving_Float
(N
);
6691 -- Mixed-mode operations can appear in a non-static universal context,
6692 -- in which case the integer argument must be converted explicitly.
6694 elsif Typ
= Universal_Real
and then Is_Integer_Type
(Rtyp
) then
6696 Convert_To
(Universal_Real
, Relocate_Node
(Ropnd
)));
6698 Analyze_And_Resolve
(Ropnd
, Universal_Real
);
6700 elsif Typ
= Universal_Real
and then Is_Integer_Type
(Ltyp
) then
6702 Convert_To
(Universal_Real
, Relocate_Node
(Lopnd
)));
6704 Analyze_And_Resolve
(Lopnd
, Universal_Real
);
6706 -- Non-fixed point cases, do integer zero divide and overflow checks
6708 elsif Is_Integer_Type
(Typ
) then
6709 Apply_Divide_Checks
(N
);
6712 -- Overflow checks for floating-point if -gnateF mode active
6714 Check_Float_Op_Overflow
(N
);
6715 end Expand_N_Op_Divide
;
6717 --------------------
6718 -- Expand_N_Op_Eq --
6719 --------------------
6721 procedure Expand_N_Op_Eq
(N
: Node_Id
) is
6722 Loc
: constant Source_Ptr
:= Sloc
(N
);
6723 Typ
: constant Entity_Id
:= Etype
(N
);
6724 Lhs
: constant Node_Id
:= Left_Opnd
(N
);
6725 Rhs
: constant Node_Id
:= Right_Opnd
(N
);
6726 Bodies
: constant List_Id
:= New_List
;
6727 A_Typ
: constant Entity_Id
:= Etype
(Lhs
);
6729 Typl
: Entity_Id
:= A_Typ
;
6730 Op_Name
: Entity_Id
;
6733 procedure Build_Equality_Call
(Eq
: Entity_Id
);
6734 -- If a constructed equality exists for the type or for its parent,
6735 -- build and analyze call, adding conversions if the operation is
6738 function Has_Unconstrained_UU_Component
(Typ
: Node_Id
) return Boolean;
6739 -- Determines whether a type has a subcomponent of an unconstrained
6740 -- Unchecked_Union subtype. Typ is a record type.
6742 -------------------------
6743 -- Build_Equality_Call --
6744 -------------------------
6746 procedure Build_Equality_Call
(Eq
: Entity_Id
) is
6747 Op_Type
: constant Entity_Id
:= Etype
(First_Formal
(Eq
));
6748 L_Exp
: Node_Id
:= Relocate_Node
(Lhs
);
6749 R_Exp
: Node_Id
:= Relocate_Node
(Rhs
);
6752 -- Adjust operands if necessary to comparison type
6754 if Base_Type
(Op_Type
) /= Base_Type
(A_Typ
)
6755 and then not Is_Class_Wide_Type
(A_Typ
)
6757 L_Exp
:= OK_Convert_To
(Op_Type
, L_Exp
);
6758 R_Exp
:= OK_Convert_To
(Op_Type
, R_Exp
);
6761 -- If we have an Unchecked_Union, we need to add the inferred
6762 -- discriminant values as actuals in the function call. At this
6763 -- point, the expansion has determined that both operands have
6764 -- inferable discriminants.
6766 if Is_Unchecked_Union
(Op_Type
) then
6768 Lhs_Type
: constant Node_Id
:= Etype
(L_Exp
);
6769 Rhs_Type
: constant Node_Id
:= Etype
(R_Exp
);
6771 Lhs_Discr_Vals
: Elist_Id
;
6772 -- List of inferred discriminant values for left operand.
6774 Rhs_Discr_Vals
: Elist_Id
;
6775 -- List of inferred discriminant values for right operand.
6780 Lhs_Discr_Vals
:= New_Elmt_List
;
6781 Rhs_Discr_Vals
:= New_Elmt_List
;
6783 -- Per-object constrained selected components require special
6784 -- attention. If the enclosing scope of the component is an
6785 -- Unchecked_Union, we cannot reference its discriminants
6786 -- directly. This is why we use the extra parameters of the
6787 -- equality function of the enclosing Unchecked_Union.
6789 -- type UU_Type (Discr : Integer := 0) is
6792 -- pragma Unchecked_Union (UU_Type);
6794 -- 1. Unchecked_Union enclosing record:
6796 -- type Enclosing_UU_Type (Discr : Integer := 0) is record
6798 -- Comp : UU_Type (Discr);
6800 -- end Enclosing_UU_Type;
6801 -- pragma Unchecked_Union (Enclosing_UU_Type);
6803 -- Obj1 : Enclosing_UU_Type;
6804 -- Obj2 : Enclosing_UU_Type (1);
6806 -- [. . .] Obj1 = Obj2 [. . .]
6810 -- if not (uu_typeEQ (obj1.comp, obj2.comp, a, b)) then
6812 -- A and B are the formal parameters of the equality function
6813 -- of Enclosing_UU_Type. The function always has two extra
6814 -- formals to capture the inferred discriminant values for
6815 -- each discriminant of the type.
6817 -- 2. Non-Unchecked_Union enclosing record:
6820 -- Enclosing_Non_UU_Type (Discr : Integer := 0)
6823 -- Comp : UU_Type (Discr);
6825 -- end Enclosing_Non_UU_Type;
6827 -- Obj1 : Enclosing_Non_UU_Type;
6828 -- Obj2 : Enclosing_Non_UU_Type (1);
6830 -- ... Obj1 = Obj2 ...
6834 -- if not (uu_typeEQ (obj1.comp, obj2.comp,
6835 -- obj1.discr, obj2.discr)) then
6837 -- In this case we can directly reference the discriminants of
6838 -- the enclosing record.
6840 -- Process left operand of equality
6842 if Nkind
(Lhs
) = N_Selected_Component
6844 Has_Per_Object_Constraint
(Entity
(Selector_Name
(Lhs
)))
6846 -- If enclosing record is an Unchecked_Union, use formals
6847 -- corresponding to each discriminant. The name of the
6848 -- formal is that of the discriminant, with added suffix,
6849 -- see Exp_Ch3.Build_Record_Equality for details.
6851 if Is_Unchecked_Union
(Scope
(Entity
(Selector_Name
(Lhs
))))
6855 (Scope
(Entity
(Selector_Name
(Lhs
))));
6856 while Present
(Discr
) loop
6858 (Make_Identifier
(Loc
,
6859 Chars
=> New_External_Name
(Chars
(Discr
), 'A')),
6860 To
=> Lhs_Discr_Vals
);
6861 Next_Discriminant
(Discr
);
6864 -- If enclosing record is of a non-Unchecked_Union type, it
6865 -- is possible to reference its discriminants directly.
6868 Discr
:= First_Discriminant
(Lhs_Type
);
6869 while Present
(Discr
) loop
6871 (Make_Selected_Component
(Loc
,
6872 Prefix
=> Prefix
(Lhs
),
6875 (Get_Discriminant_Value
(Discr
,
6877 Stored_Constraint
(Lhs_Type
)))),
6878 To
=> Lhs_Discr_Vals
);
6879 Next_Discriminant
(Discr
);
6883 -- Otherwise operand is on object with a constrained type.
6884 -- Infer the discriminant values from the constraint.
6888 Discr
:= First_Discriminant
(Lhs_Type
);
6889 while Present
(Discr
) loop
6892 (Get_Discriminant_Value
(Discr
,
6894 Stored_Constraint
(Lhs_Type
))),
6895 To
=> Lhs_Discr_Vals
);
6896 Next_Discriminant
(Discr
);
6900 -- Similar processing for right operand of equality
6902 if Nkind
(Rhs
) = N_Selected_Component
6904 Has_Per_Object_Constraint
(Entity
(Selector_Name
(Rhs
)))
6906 if Is_Unchecked_Union
6907 (Scope
(Entity
(Selector_Name
(Rhs
))))
6911 (Scope
(Entity
(Selector_Name
(Rhs
))));
6912 while Present
(Discr
) loop
6914 (Make_Identifier
(Loc
,
6915 Chars
=> New_External_Name
(Chars
(Discr
), 'B')),
6916 To
=> Rhs_Discr_Vals
);
6917 Next_Discriminant
(Discr
);
6921 Discr
:= First_Discriminant
(Rhs_Type
);
6922 while Present
(Discr
) loop
6924 (Make_Selected_Component
(Loc
,
6925 Prefix
=> Prefix
(Rhs
),
6927 New_Copy
(Get_Discriminant_Value
6930 Stored_Constraint
(Rhs_Type
)))),
6931 To
=> Rhs_Discr_Vals
);
6932 Next_Discriminant
(Discr
);
6937 Discr
:= First_Discriminant
(Rhs_Type
);
6938 while Present
(Discr
) loop
6940 (New_Copy
(Get_Discriminant_Value
6943 Stored_Constraint
(Rhs_Type
))),
6944 To
=> Rhs_Discr_Vals
);
6945 Next_Discriminant
(Discr
);
6949 -- Now merge the list of discriminant values so that values
6950 -- of corresponding discriminants are adjacent.
6958 Params
:= New_List
(L_Exp
, R_Exp
);
6959 L_Elmt
:= First_Elmt
(Lhs_Discr_Vals
);
6960 R_Elmt
:= First_Elmt
(Rhs_Discr_Vals
);
6961 while Present
(L_Elmt
) loop
6962 Append_To
(Params
, Node
(L_Elmt
));
6963 Append_To
(Params
, Node
(R_Elmt
));
6969 Make_Function_Call
(Loc
,
6970 Name
=> New_Occurrence_Of
(Eq
, Loc
),
6971 Parameter_Associations
=> Params
));
6975 -- Normal case, not an unchecked union
6979 Make_Function_Call
(Loc
,
6980 Name
=> New_Occurrence_Of
(Eq
, Loc
),
6981 Parameter_Associations
=> New_List
(L_Exp
, R_Exp
)));
6984 Analyze_And_Resolve
(N
, Standard_Boolean
, Suppress
=> All_Checks
);
6985 end Build_Equality_Call
;
6987 ------------------------------------
6988 -- Has_Unconstrained_UU_Component --
6989 ------------------------------------
6991 function Has_Unconstrained_UU_Component
6992 (Typ
: Node_Id
) return Boolean
6994 Tdef
: constant Node_Id
:=
6995 Type_Definition
(Declaration_Node
(Base_Type
(Typ
)));
6999 function Component_Is_Unconstrained_UU
7000 (Comp
: Node_Id
) return Boolean;
7001 -- Determines whether the subtype of the component is an
7002 -- unconstrained Unchecked_Union.
7004 function Variant_Is_Unconstrained_UU
7005 (Variant
: Node_Id
) return Boolean;
7006 -- Determines whether a component of the variant has an unconstrained
7007 -- Unchecked_Union subtype.
7009 -----------------------------------
7010 -- Component_Is_Unconstrained_UU --
7011 -----------------------------------
7013 function Component_Is_Unconstrained_UU
7014 (Comp
: Node_Id
) return Boolean
7017 if Nkind
(Comp
) /= N_Component_Declaration
then
7022 Sindic
: constant Node_Id
:=
7023 Subtype_Indication
(Component_Definition
(Comp
));
7026 -- Unconstrained nominal type. In the case of a constraint
7027 -- present, the node kind would have been N_Subtype_Indication.
7029 if Nkind
(Sindic
) = N_Identifier
then
7030 return Is_Unchecked_Union
(Base_Type
(Etype
(Sindic
)));
7035 end Component_Is_Unconstrained_UU
;
7037 ---------------------------------
7038 -- Variant_Is_Unconstrained_UU --
7039 ---------------------------------
7041 function Variant_Is_Unconstrained_UU
7042 (Variant
: Node_Id
) return Boolean
7044 Clist
: constant Node_Id
:= Component_List
(Variant
);
7047 if Is_Empty_List
(Component_Items
(Clist
)) then
7051 -- We only need to test one component
7054 Comp
: Node_Id
:= First
(Component_Items
(Clist
));
7057 while Present
(Comp
) loop
7058 if Component_Is_Unconstrained_UU
(Comp
) then
7066 -- None of the components withing the variant were of
7067 -- unconstrained Unchecked_Union type.
7070 end Variant_Is_Unconstrained_UU
;
7072 -- Start of processing for Has_Unconstrained_UU_Component
7075 if Null_Present
(Tdef
) then
7079 Clist
:= Component_List
(Tdef
);
7080 Vpart
:= Variant_Part
(Clist
);
7082 -- Inspect available components
7084 if Present
(Component_Items
(Clist
)) then
7086 Comp
: Node_Id
:= First
(Component_Items
(Clist
));
7089 while Present
(Comp
) loop
7091 -- One component is sufficient
7093 if Component_Is_Unconstrained_UU
(Comp
) then
7102 -- Inspect available components withing variants
7104 if Present
(Vpart
) then
7106 Variant
: Node_Id
:= First
(Variants
(Vpart
));
7109 while Present
(Variant
) loop
7111 -- One component within a variant is sufficient
7113 if Variant_Is_Unconstrained_UU
(Variant
) then
7122 -- Neither the available components, nor the components inside the
7123 -- variant parts were of an unconstrained Unchecked_Union subtype.
7126 end Has_Unconstrained_UU_Component
;
7128 -- Start of processing for Expand_N_Op_Eq
7131 Binary_Op_Validity_Checks
(N
);
7133 -- Deal with private types
7135 if Ekind
(Typl
) = E_Private_Type
then
7136 Typl
:= Underlying_Type
(Typl
);
7137 elsif Ekind
(Typl
) = E_Private_Subtype
then
7138 Typl
:= Underlying_Type
(Base_Type
(Typl
));
7143 -- It may happen in error situations that the underlying type is not
7144 -- set. The error will be detected later, here we just defend the
7151 Typl
:= Base_Type
(Typl
);
7153 -- Equality between variant records results in a call to a routine
7154 -- that has conditional tests of the discriminant value(s), and hence
7155 -- violates the No_Implicit_Conditionals restriction.
7157 if Has_Variant_Part
(Typl
) then
7162 Check_Restriction
(Msg
, No_Implicit_Conditionals
, N
);
7166 ("\comparison of variant records tests discriminants", N
);
7172 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if that
7173 -- means we no longer have a comparison operation, we are all done.
7175 Expand_Compare_Minimize_Eliminate_Overflow
(N
);
7177 if Nkind
(N
) /= N_Op_Eq
then
7181 -- Boolean types (requiring handling of non-standard case)
7183 if Is_Boolean_Type
(Typl
) then
7184 Adjust_Condition
(Left_Opnd
(N
));
7185 Adjust_Condition
(Right_Opnd
(N
));
7186 Set_Etype
(N
, Standard_Boolean
);
7187 Adjust_Result_Type
(N
, Typ
);
7191 elsif Is_Array_Type
(Typl
) then
7193 -- If we are doing full validity checking, and it is possible for the
7194 -- array elements to be invalid then expand out array comparisons to
7195 -- make sure that we check the array elements.
7197 if Validity_Check_Operands
7198 and then not Is_Known_Valid
(Component_Type
(Typl
))
7201 Save_Force_Validity_Checks
: constant Boolean :=
7202 Force_Validity_Checks
;
7204 Force_Validity_Checks
:= True;
7206 Expand_Array_Equality
7208 Relocate_Node
(Lhs
),
7209 Relocate_Node
(Rhs
),
7212 Insert_Actions
(N
, Bodies
);
7213 Analyze_And_Resolve
(N
, Standard_Boolean
);
7214 Force_Validity_Checks
:= Save_Force_Validity_Checks
;
7217 -- Packed case where both operands are known aligned
7219 elsif Is_Bit_Packed_Array
(Typl
)
7220 and then not Is_Possibly_Unaligned_Object
(Lhs
)
7221 and then not Is_Possibly_Unaligned_Object
(Rhs
)
7223 Expand_Packed_Eq
(N
);
7225 -- Where the component type is elementary we can use a block bit
7226 -- comparison (if supported on the target) exception in the case
7227 -- of floating-point (negative zero issues require element by
7228 -- element comparison), and atomic types (where we must be sure
7229 -- to load elements independently) and possibly unaligned arrays.
7231 elsif Is_Elementary_Type
(Component_Type
(Typl
))
7232 and then not Is_Floating_Point_Type
(Component_Type
(Typl
))
7233 and then not Is_Atomic
(Component_Type
(Typl
))
7234 and then not Is_Possibly_Unaligned_Object
(Lhs
)
7235 and then not Is_Possibly_Unaligned_Object
(Rhs
)
7236 and then Support_Composite_Compare_On_Target
7240 -- For composite and floating-point cases, expand equality loop to
7241 -- make sure of using proper comparisons for tagged types, and
7242 -- correctly handling the floating-point case.
7246 Expand_Array_Equality
7248 Relocate_Node
(Lhs
),
7249 Relocate_Node
(Rhs
),
7252 Insert_Actions
(N
, Bodies
, Suppress
=> All_Checks
);
7253 Analyze_And_Resolve
(N
, Standard_Boolean
, Suppress
=> All_Checks
);
7258 elsif Is_Record_Type
(Typl
) then
7260 -- For tagged types, use the primitive "="
7262 if Is_Tagged_Type
(Typl
) then
7264 -- No need to do anything else compiling under restriction
7265 -- No_Dispatching_Calls. During the semantic analysis we
7266 -- already notified such violation.
7268 if Restriction_Active
(No_Dispatching_Calls
) then
7272 -- If this is derived from an untagged private type completed with
7273 -- a tagged type, it does not have a full view, so we use the
7274 -- primitive operations of the private type. This check should no
7275 -- longer be necessary when these types get their full views???
7277 if Is_Private_Type
(A_Typ
)
7278 and then not Is_Tagged_Type
(A_Typ
)
7279 and then Is_Derived_Type
(A_Typ
)
7280 and then No
(Full_View
(A_Typ
))
7282 -- Search for equality operation, checking that the operands
7283 -- have the same type. Note that we must find a matching entry,
7284 -- or something is very wrong.
7286 Prim
:= First_Elmt
(Collect_Primitive_Operations
(A_Typ
));
7288 while Present
(Prim
) loop
7289 exit when Chars
(Node
(Prim
)) = Name_Op_Eq
7290 and then Etype
(First_Formal
(Node
(Prim
))) =
7291 Etype
(Next_Formal
(First_Formal
(Node
(Prim
))))
7293 Base_Type
(Etype
(Node
(Prim
))) = Standard_Boolean
;
7298 pragma Assert
(Present
(Prim
));
7299 Op_Name
:= Node
(Prim
);
7301 -- Find the type's predefined equality or an overriding
7302 -- user-defined equality. The reason for not simply calling
7303 -- Find_Prim_Op here is that there may be a user-defined
7304 -- overloaded equality op that precedes the equality that we
7305 -- want, so we have to explicitly search (e.g., there could be
7306 -- an equality with two different parameter types).
7309 if Is_Class_Wide_Type
(Typl
) then
7310 Typl
:= Find_Specific_Type
(Typl
);
7313 Prim
:= First_Elmt
(Primitive_Operations
(Typl
));
7314 while Present
(Prim
) loop
7315 exit when Chars
(Node
(Prim
)) = Name_Op_Eq
7316 and then Etype
(First_Formal
(Node
(Prim
))) =
7317 Etype
(Next_Formal
(First_Formal
(Node
(Prim
))))
7319 Base_Type
(Etype
(Node
(Prim
))) = Standard_Boolean
;
7324 pragma Assert
(Present
(Prim
));
7325 Op_Name
:= Node
(Prim
);
7328 Build_Equality_Call
(Op_Name
);
7330 -- Ada 2005 (AI-216): Program_Error is raised when evaluating the
7331 -- predefined equality operator for a type which has a subcomponent
7332 -- of an Unchecked_Union type whose nominal subtype is unconstrained.
7334 elsif Has_Unconstrained_UU_Component
(Typl
) then
7336 Make_Raise_Program_Error
(Loc
,
7337 Reason
=> PE_Unchecked_Union_Restriction
));
7339 -- Prevent Gigi from generating incorrect code by rewriting the
7340 -- equality as a standard False. (is this documented somewhere???)
7343 New_Occurrence_Of
(Standard_False
, Loc
));
7345 elsif Is_Unchecked_Union
(Typl
) then
7347 -- If we can infer the discriminants of the operands, we make a
7348 -- call to the TSS equality function.
7350 if Has_Inferable_Discriminants
(Lhs
)
7352 Has_Inferable_Discriminants
(Rhs
)
7355 (TSS
(Root_Type
(Typl
), TSS_Composite_Equality
));
7358 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
7359 -- the predefined equality operator for an Unchecked_Union type
7360 -- if either of the operands lack inferable discriminants.
7363 Make_Raise_Program_Error
(Loc
,
7364 Reason
=> PE_Unchecked_Union_Restriction
));
7366 -- Emit a warning on source equalities only, otherwise the
7367 -- message may appear out of place due to internal use. The
7368 -- warning is unconditional because it is required by the
7371 if Comes_From_Source
(N
) then
7373 ("Unchecked_Union discriminants cannot be determined??",
7376 ("\Program_Error will be raised for equality operation??",
7380 -- Prevent Gigi from generating incorrect code by rewriting
7381 -- the equality as a standard False (documented where???).
7384 New_Occurrence_Of
(Standard_False
, Loc
));
7387 -- If a type support function is present (for complex cases), use it
7389 elsif Present
(TSS
(Root_Type
(Typl
), TSS_Composite_Equality
)) then
7391 (TSS
(Root_Type
(Typl
), TSS_Composite_Equality
));
7393 -- When comparing two Bounded_Strings, use the primitive equality of
7394 -- the root Super_String type.
7396 elsif Is_Bounded_String
(Typl
) then
7398 First_Elmt
(Collect_Primitive_Operations
(Root_Type
(Typl
)));
7400 while Present
(Prim
) loop
7401 exit when Chars
(Node
(Prim
)) = Name_Op_Eq
7402 and then Etype
(First_Formal
(Node
(Prim
))) =
7403 Etype
(Next_Formal
(First_Formal
(Node
(Prim
))))
7404 and then Base_Type
(Etype
(Node
(Prim
))) = Standard_Boolean
;
7409 -- A Super_String type should always have a primitive equality
7411 pragma Assert
(Present
(Prim
));
7412 Build_Equality_Call
(Node
(Prim
));
7414 -- Otherwise expand the component by component equality. Note that
7415 -- we never use block-bit comparisons for records, because of the
7416 -- problems with gaps. The backend will often be able to recombine
7417 -- the separate comparisons that we generate here.
7420 Remove_Side_Effects
(Lhs
);
7421 Remove_Side_Effects
(Rhs
);
7423 Expand_Record_Equality
(N
, Typl
, Lhs
, Rhs
, Bodies
));
7425 Insert_Actions
(N
, Bodies
, Suppress
=> All_Checks
);
7426 Analyze_And_Resolve
(N
, Standard_Boolean
, Suppress
=> All_Checks
);
7430 -- Test if result is known at compile time
7432 Rewrite_Comparison
(N
);
7434 Optimize_Length_Comparison
(N
);
7437 -----------------------
7438 -- Expand_N_Op_Expon --
7439 -----------------------
7441 procedure Expand_N_Op_Expon
(N
: Node_Id
) is
7442 Loc
: constant Source_Ptr
:= Sloc
(N
);
7443 Typ
: constant Entity_Id
:= Etype
(N
);
7444 Rtyp
: constant Entity_Id
:= Root_Type
(Typ
);
7445 Base
: constant Node_Id
:= Relocate_Node
(Left_Opnd
(N
));
7446 Bastyp
: constant Node_Id
:= Etype
(Base
);
7447 Exp
: constant Node_Id
:= Relocate_Node
(Right_Opnd
(N
));
7448 Exptyp
: constant Entity_Id
:= Etype
(Exp
);
7449 Ovflo
: constant Boolean := Do_Overflow_Check
(N
);
7458 Binary_Op_Validity_Checks
(N
);
7460 -- CodePeer wants to see the unexpanded N_Op_Expon node
7462 if CodePeer_Mode
then
7466 -- If either operand is of a private type, then we have the use of an
7467 -- intrinsic operator, and we get rid of the privateness, by using root
7468 -- types of underlying types for the actual operation. Otherwise the
7469 -- private types will cause trouble if we expand multiplications or
7470 -- shifts etc. We also do this transformation if the result type is
7471 -- different from the base type.
7473 if Is_Private_Type
(Etype
(Base
))
7474 or else Is_Private_Type
(Typ
)
7475 or else Is_Private_Type
(Exptyp
)
7476 or else Rtyp
/= Root_Type
(Bastyp
)
7479 Bt
: constant Entity_Id
:= Root_Type
(Underlying_Type
(Bastyp
));
7480 Et
: constant Entity_Id
:= Root_Type
(Underlying_Type
(Exptyp
));
7483 Unchecked_Convert_To
(Typ
,
7485 Left_Opnd
=> Unchecked_Convert_To
(Bt
, Base
),
7486 Right_Opnd
=> Unchecked_Convert_To
(Et
, Exp
))));
7487 Analyze_And_Resolve
(N
, Typ
);
7492 -- Check for MINIMIZED/ELIMINATED overflow mode
7494 if Minimized_Eliminated_Overflow_Check
(N
) then
7495 Apply_Arithmetic_Overflow_Check
(N
);
7499 -- Test for case of known right argument where we can replace the
7500 -- exponentiation by an equivalent expression using multiplication.
7502 -- Note: use CRT_Safe version of Compile_Time_Known_Value because in
7503 -- configurable run-time mode, we may not have the exponentiation
7504 -- routine available, and we don't want the legality of the program
7505 -- to depend on how clever the compiler is in knowing values.
7507 if CRT_Safe_Compile_Time_Known_Value
(Exp
) then
7508 Expv
:= Expr_Value
(Exp
);
7510 -- We only fold small non-negative exponents. You might think we
7511 -- could fold small negative exponents for the real case, but we
7512 -- can't because we are required to raise Constraint_Error for
7513 -- the case of 0.0 ** (negative) even if Machine_Overflows = False.
7514 -- See ACVC test C4A012B.
7516 if Expv
>= 0 and then Expv
<= 4 then
7518 -- X ** 0 = 1 (or 1.0)
7522 -- Call Remove_Side_Effects to ensure that any side effects
7523 -- in the ignored left operand (in particular function calls
7524 -- to user defined functions) are properly executed.
7526 Remove_Side_Effects
(Base
);
7528 if Ekind
(Typ
) in Integer_Kind
then
7529 Xnode
:= Make_Integer_Literal
(Loc
, Intval
=> 1);
7531 Xnode
:= Make_Real_Literal
(Loc
, Ureal_1
);
7543 Make_Op_Multiply
(Loc
,
7544 Left_Opnd
=> Duplicate_Subexpr
(Base
),
7545 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Base
));
7547 -- X ** 3 = X * X * X
7551 Make_Op_Multiply
(Loc
,
7553 Make_Op_Multiply
(Loc
,
7554 Left_Opnd
=> Duplicate_Subexpr
(Base
),
7555 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Base
)),
7556 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Base
));
7561 -- En : constant base'type := base * base;
7566 pragma Assert
(Expv
= 4);
7567 Temp
:= Make_Temporary
(Loc
, 'E', Base
);
7570 Make_Expression_With_Actions
(Loc
,
7571 Actions
=> New_List
(
7572 Make_Object_Declaration
(Loc
,
7573 Defining_Identifier
=> Temp
,
7574 Constant_Present
=> True,
7575 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
),
7577 Make_Op_Multiply
(Loc
,
7579 Duplicate_Subexpr
(Base
),
7581 Duplicate_Subexpr_No_Checks
(Base
)))),
7584 Make_Op_Multiply
(Loc
,
7585 Left_Opnd
=> New_Occurrence_Of
(Temp
, Loc
),
7586 Right_Opnd
=> New_Occurrence_Of
(Temp
, Loc
)));
7590 Analyze_And_Resolve
(N
, Typ
);
7595 -- Case of (2 ** expression) appearing as an argument of an integer
7596 -- multiplication, or as the right argument of a division of a non-
7597 -- negative integer. In such cases we leave the node untouched, setting
7598 -- the flag Is_Natural_Power_Of_2_for_Shift set, then the expansion
7599 -- of the higher level node converts it into a shift.
7601 -- Another case is 2 ** N in any other context. We simply convert
7602 -- this to 1 * 2 ** N, and then the above transformation applies.
7604 -- Note: this transformation is not applicable for a modular type with
7605 -- a non-binary modulus in the multiplication case, since we get a wrong
7606 -- result if the shift causes an overflow before the modular reduction.
7608 -- Note: we used to check that Exptyp was an unsigned type. But that is
7609 -- an unnecessary check, since if Exp is negative, we have a run-time
7610 -- error that is either caught (so we get the right result) or we have
7611 -- suppressed the check, in which case the code is erroneous anyway.
7613 if Nkind
(Base
) = N_Integer_Literal
7614 and then CRT_Safe_Compile_Time_Known_Value
(Base
)
7615 and then Expr_Value
(Base
) = Uint_2
7616 and then Is_Integer_Type
(Root_Type
(Exptyp
))
7617 and then Esize
(Root_Type
(Exptyp
)) <= Esize
(Standard_Integer
)
7620 -- First the multiply and divide cases
7622 if Nkind_In
(Parent
(N
), N_Op_Divide
, N_Op_Multiply
) then
7624 P
: constant Node_Id
:= Parent
(N
);
7625 L
: constant Node_Id
:= Left_Opnd
(P
);
7626 R
: constant Node_Id
:= Right_Opnd
(P
);
7629 if (Nkind
(P
) = N_Op_Multiply
7630 and then not Non_Binary_Modulus
(Typ
)
7632 ((Is_Integer_Type
(Etype
(L
)) and then R
= N
)
7634 (Is_Integer_Type
(Etype
(R
)) and then L
= N
))
7635 and then not Do_Overflow_Check
(P
))
7637 (Nkind
(P
) = N_Op_Divide
7638 and then Is_Integer_Type
(Etype
(L
))
7639 and then Is_Unsigned_Type
(Etype
(L
))
7641 and then not Do_Overflow_Check
(P
))
7643 Set_Is_Power_Of_2_For_Shift
(N
);
7648 -- Now the other cases
7650 elsif not Non_Binary_Modulus
(Typ
) then
7652 Make_Op_Multiply
(Loc
,
7653 Left_Opnd
=> Make_Integer_Literal
(Loc
, 1),
7654 Right_Opnd
=> Relocate_Node
(N
)));
7655 Analyze_And_Resolve
(N
, Typ
);
7660 -- Fall through if exponentiation must be done using a runtime routine
7662 -- First deal with modular case
7664 if Is_Modular_Integer_Type
(Rtyp
) then
7666 -- Non-binary case, we call the special exponentiation routine for
7667 -- the non-binary case, converting the argument to Long_Long_Integer
7668 -- and passing the modulus value. Then the result is converted back
7669 -- to the base type.
7671 if Non_Binary_Modulus
(Rtyp
) then
7674 Make_Function_Call
(Loc
,
7676 New_Occurrence_Of
(RTE
(RE_Exp_Modular
), Loc
),
7677 Parameter_Associations
=> New_List
(
7678 Convert_To
(RTE
(RE_Unsigned
), Base
),
7679 Make_Integer_Literal
(Loc
, Modulus
(Rtyp
)),
7682 -- Binary case, in this case, we call one of two routines, either the
7683 -- unsigned integer case, or the unsigned long long integer case,
7684 -- with a final "and" operation to do the required mod.
7687 if UI_To_Int
(Esize
(Rtyp
)) <= Standard_Integer_Size
then
7688 Ent
:= RTE
(RE_Exp_Unsigned
);
7690 Ent
:= RTE
(RE_Exp_Long_Long_Unsigned
);
7697 Make_Function_Call
(Loc
,
7698 Name
=> New_Occurrence_Of
(Ent
, Loc
),
7699 Parameter_Associations
=> New_List
(
7700 Convert_To
(Etype
(First_Formal
(Ent
)), Base
),
7703 Make_Integer_Literal
(Loc
, Modulus
(Rtyp
) - 1))));
7707 -- Common exit point for modular type case
7709 Analyze_And_Resolve
(N
, Typ
);
7712 -- Signed integer cases, done using either Integer or Long_Long_Integer.
7713 -- It is not worth having routines for Short_[Short_]Integer, since for
7714 -- most machines it would not help, and it would generate more code that
7715 -- might need certification when a certified run time is required.
7717 -- In the integer cases, we have two routines, one for when overflow
7718 -- checks are required, and one when they are not required, since there
7719 -- is a real gain in omitting checks on many machines.
7721 elsif Rtyp
= Base_Type
(Standard_Long_Long_Integer
)
7722 or else (Rtyp
= Base_Type
(Standard_Long_Integer
)
7724 Esize
(Standard_Long_Integer
) > Esize
(Standard_Integer
))
7725 or else Rtyp
= Universal_Integer
7727 Etyp
:= Standard_Long_Long_Integer
;
7729 -- Overflow checking is the only choice on the AAMP target, where
7730 -- arithmetic instructions check overflow automatically, so only
7731 -- one version of the exponentiation unit is needed.
7733 if Ovflo
or AAMP_On_Target
then
7734 Rent
:= RE_Exp_Long_Long_Integer
;
7736 Rent
:= RE_Exn_Long_Long_Integer
;
7739 elsif Is_Signed_Integer_Type
(Rtyp
) then
7740 Etyp
:= Standard_Integer
;
7742 -- Overflow checking is the only choice on the AAMP target, where
7743 -- arithmetic instructions check overflow automatically, so only
7744 -- one version of the exponentiation unit is needed.
7746 if Ovflo
or AAMP_On_Target
then
7747 Rent
:= RE_Exp_Integer
;
7749 Rent
:= RE_Exn_Integer
;
7752 -- Floating-point cases, always done using Long_Long_Float. We do not
7753 -- need separate routines for the overflow case here, since in the case
7754 -- of floating-point, we generate infinities anyway as a rule (either
7755 -- that or we automatically trap overflow), and if there is an infinity
7756 -- generated and a range check is required, the check will fail anyway.
7759 pragma Assert
(Is_Floating_Point_Type
(Rtyp
));
7760 Etyp
:= Standard_Long_Long_Float
;
7761 Rent
:= RE_Exn_Long_Long_Float
;
7764 -- Common processing for integer cases and floating-point cases.
7765 -- If we are in the right type, we can call runtime routine directly
7768 and then Rtyp
/= Universal_Integer
7769 and then Rtyp
/= Universal_Real
7772 Make_Function_Call
(Loc
,
7773 Name
=> New_Occurrence_Of
(RTE
(Rent
), Loc
),
7774 Parameter_Associations
=> New_List
(Base
, Exp
)));
7776 -- Otherwise we have to introduce conversions (conversions are also
7777 -- required in the universal cases, since the runtime routine is
7778 -- typed using one of the standard types).
7783 Make_Function_Call
(Loc
,
7784 Name
=> New_Occurrence_Of
(RTE
(Rent
), Loc
),
7785 Parameter_Associations
=> New_List
(
7786 Convert_To
(Etyp
, Base
),
7790 Analyze_And_Resolve
(N
, Typ
);
7794 when RE_Not_Available
=>
7796 end Expand_N_Op_Expon
;
7798 --------------------
7799 -- Expand_N_Op_Ge --
7800 --------------------
7802 procedure Expand_N_Op_Ge
(N
: Node_Id
) is
7803 Typ
: constant Entity_Id
:= Etype
(N
);
7804 Op1
: constant Node_Id
:= Left_Opnd
(N
);
7805 Op2
: constant Node_Id
:= Right_Opnd
(N
);
7806 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
7809 Binary_Op_Validity_Checks
(N
);
7811 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if that
7812 -- means we no longer have a comparison operation, we are all done.
7814 Expand_Compare_Minimize_Eliminate_Overflow
(N
);
7816 if Nkind
(N
) /= N_Op_Ge
then
7822 if Is_Array_Type
(Typ1
) then
7823 Expand_Array_Comparison
(N
);
7827 -- Deal with boolean operands
7829 if Is_Boolean_Type
(Typ1
) then
7830 Adjust_Condition
(Op1
);
7831 Adjust_Condition
(Op2
);
7832 Set_Etype
(N
, Standard_Boolean
);
7833 Adjust_Result_Type
(N
, Typ
);
7836 Rewrite_Comparison
(N
);
7838 Optimize_Length_Comparison
(N
);
7841 --------------------
7842 -- Expand_N_Op_Gt --
7843 --------------------
7845 procedure Expand_N_Op_Gt
(N
: Node_Id
) is
7846 Typ
: constant Entity_Id
:= Etype
(N
);
7847 Op1
: constant Node_Id
:= Left_Opnd
(N
);
7848 Op2
: constant Node_Id
:= Right_Opnd
(N
);
7849 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
7852 Binary_Op_Validity_Checks
(N
);
7854 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if that
7855 -- means we no longer have a comparison operation, we are all done.
7857 Expand_Compare_Minimize_Eliminate_Overflow
(N
);
7859 if Nkind
(N
) /= N_Op_Gt
then
7863 -- Deal with array type operands
7865 if Is_Array_Type
(Typ1
) then
7866 Expand_Array_Comparison
(N
);
7870 -- Deal with boolean type operands
7872 if Is_Boolean_Type
(Typ1
) then
7873 Adjust_Condition
(Op1
);
7874 Adjust_Condition
(Op2
);
7875 Set_Etype
(N
, Standard_Boolean
);
7876 Adjust_Result_Type
(N
, Typ
);
7879 Rewrite_Comparison
(N
);
7881 Optimize_Length_Comparison
(N
);
7884 --------------------
7885 -- Expand_N_Op_Le --
7886 --------------------
7888 procedure Expand_N_Op_Le
(N
: Node_Id
) is
7889 Typ
: constant Entity_Id
:= Etype
(N
);
7890 Op1
: constant Node_Id
:= Left_Opnd
(N
);
7891 Op2
: constant Node_Id
:= Right_Opnd
(N
);
7892 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
7895 Binary_Op_Validity_Checks
(N
);
7897 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if that
7898 -- means we no longer have a comparison operation, we are all done.
7900 Expand_Compare_Minimize_Eliminate_Overflow
(N
);
7902 if Nkind
(N
) /= N_Op_Le
then
7906 -- Deal with array type operands
7908 if Is_Array_Type
(Typ1
) then
7909 Expand_Array_Comparison
(N
);
7913 -- Deal with Boolean type operands
7915 if Is_Boolean_Type
(Typ1
) then
7916 Adjust_Condition
(Op1
);
7917 Adjust_Condition
(Op2
);
7918 Set_Etype
(N
, Standard_Boolean
);
7919 Adjust_Result_Type
(N
, Typ
);
7922 Rewrite_Comparison
(N
);
7924 Optimize_Length_Comparison
(N
);
7927 --------------------
7928 -- Expand_N_Op_Lt --
7929 --------------------
7931 procedure Expand_N_Op_Lt
(N
: Node_Id
) is
7932 Typ
: constant Entity_Id
:= Etype
(N
);
7933 Op1
: constant Node_Id
:= Left_Opnd
(N
);
7934 Op2
: constant Node_Id
:= Right_Opnd
(N
);
7935 Typ1
: constant Entity_Id
:= Base_Type
(Etype
(Op1
));
7938 Binary_Op_Validity_Checks
(N
);
7940 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if that
7941 -- means we no longer have a comparison operation, we are all done.
7943 Expand_Compare_Minimize_Eliminate_Overflow
(N
);
7945 if Nkind
(N
) /= N_Op_Lt
then
7949 -- Deal with array type operands
7951 if Is_Array_Type
(Typ1
) then
7952 Expand_Array_Comparison
(N
);
7956 -- Deal with Boolean type operands
7958 if Is_Boolean_Type
(Typ1
) then
7959 Adjust_Condition
(Op1
);
7960 Adjust_Condition
(Op2
);
7961 Set_Etype
(N
, Standard_Boolean
);
7962 Adjust_Result_Type
(N
, Typ
);
7965 Rewrite_Comparison
(N
);
7967 Optimize_Length_Comparison
(N
);
7970 -----------------------
7971 -- Expand_N_Op_Minus --
7972 -----------------------
7974 procedure Expand_N_Op_Minus
(N
: Node_Id
) is
7975 Loc
: constant Source_Ptr
:= Sloc
(N
);
7976 Typ
: constant Entity_Id
:= Etype
(N
);
7979 Unary_Op_Validity_Checks
(N
);
7981 -- Check for MINIMIZED/ELIMINATED overflow mode
7983 if Minimized_Eliminated_Overflow_Check
(N
) then
7984 Apply_Arithmetic_Overflow_Check
(N
);
7988 if not Backend_Overflow_Checks_On_Target
7989 and then Is_Signed_Integer_Type
(Etype
(N
))
7990 and then Do_Overflow_Check
(N
)
7992 -- Software overflow checking expands -expr into (0 - expr)
7995 Make_Op_Subtract
(Loc
,
7996 Left_Opnd
=> Make_Integer_Literal
(Loc
, 0),
7997 Right_Opnd
=> Right_Opnd
(N
)));
7999 Analyze_And_Resolve
(N
, Typ
);
8001 end Expand_N_Op_Minus
;
8003 ---------------------
8004 -- Expand_N_Op_Mod --
8005 ---------------------
8007 procedure Expand_N_Op_Mod
(N
: Node_Id
) is
8008 Loc
: constant Source_Ptr
:= Sloc
(N
);
8009 Typ
: constant Entity_Id
:= Etype
(N
);
8010 DDC
: constant Boolean := Do_Division_Check
(N
);
8023 pragma Warnings
(Off
, Lhi
);
8026 Binary_Op_Validity_Checks
(N
);
8028 -- Check for MINIMIZED/ELIMINATED overflow mode
8030 if Minimized_Eliminated_Overflow_Check
(N
) then
8031 Apply_Arithmetic_Overflow_Check
(N
);
8035 if Is_Integer_Type
(Etype
(N
)) then
8036 Apply_Divide_Checks
(N
);
8038 -- All done if we don't have a MOD any more, which can happen as a
8039 -- result of overflow expansion in MINIMIZED or ELIMINATED modes.
8041 if Nkind
(N
) /= N_Op_Mod
then
8046 -- Proceed with expansion of mod operator
8048 Left
:= Left_Opnd
(N
);
8049 Right
:= Right_Opnd
(N
);
8051 Determine_Range
(Right
, ROK
, Rlo
, Rhi
, Assume_Valid
=> True);
8052 Determine_Range
(Left
, LOK
, Llo
, Lhi
, Assume_Valid
=> True);
8054 -- Convert mod to rem if operands are both known to be non-negative, or
8055 -- both known to be non-positive (these are the cases in which rem and
8056 -- mod are the same, see (RM 4.5.5(28-30)). We do this since it is quite
8057 -- likely that this will improve the quality of code, (the operation now
8058 -- corresponds to the hardware remainder), and it does not seem likely
8059 -- that it could be harmful. It also avoids some cases of the elaborate
8060 -- expansion in Modify_Tree_For_C mode below (since Ada rem = C %).
8063 and then ((Llo
>= 0 and then Rlo
>= 0)
8065 (Lhi
<= 0 and then Rhi
<= 0))
8068 Make_Op_Rem
(Sloc
(N
),
8069 Left_Opnd
=> Left_Opnd
(N
),
8070 Right_Opnd
=> Right_Opnd
(N
)));
8072 -- Instead of reanalyzing the node we do the analysis manually. This
8073 -- avoids anomalies when the replacement is done in an instance and
8074 -- is epsilon more efficient.
8076 Set_Entity
(N
, Standard_Entity
(S_Op_Rem
));
8078 Set_Do_Division_Check
(N
, DDC
);
8079 Expand_N_Op_Rem
(N
);
8083 -- Otherwise, normal mod processing
8086 -- Apply optimization x mod 1 = 0. We don't really need that with
8087 -- gcc, but it is useful with other back ends (e.g. AAMP), and is
8088 -- certainly harmless.
8090 if Is_Integer_Type
(Etype
(N
))
8091 and then Compile_Time_Known_Value
(Right
)
8092 and then Expr_Value
(Right
) = Uint_1
8094 -- Call Remove_Side_Effects to ensure that any side effects in
8095 -- the ignored left operand (in particular function calls to
8096 -- user defined functions) are properly executed.
8098 Remove_Side_Effects
(Left
);
8100 Rewrite
(N
, Make_Integer_Literal
(Loc
, 0));
8101 Analyze_And_Resolve
(N
, Typ
);
8105 -- If we still have a mod operator and we are in Modify_Tree_For_C
8106 -- mode, and we have a signed integer type, then here is where we do
8107 -- the rewrite in terms of Rem. Note this rewrite bypasses the need
8108 -- for the special handling of the annoying case of largest negative
8109 -- number mod minus one.
8111 if Nkind
(N
) = N_Op_Mod
8112 and then Is_Signed_Integer_Type
(Typ
)
8113 and then Modify_Tree_For_C
8115 -- In the general case, we expand A mod B as
8117 -- Tnn : constant typ := A rem B;
8119 -- (if (A >= 0) = (B >= 0) then Tnn
8120 -- elsif Tnn = 0 then 0
8123 -- The comparison can be written simply as A >= 0 if we know that
8124 -- B >= 0 which is a very common case.
8126 -- An important optimization is when B is known at compile time
8127 -- to be 2**K for some constant. In this case we can simply AND
8128 -- the left operand with the bit string 2**K-1 (i.e. K 1-bits)
8129 -- and that works for both the positive and negative cases.
8132 P2
: constant Nat
:= Power_Of_Two
(Right
);
8137 Unchecked_Convert_To
(Typ
,
8140 Unchecked_Convert_To
8141 (Corresponding_Unsigned_Type
(Typ
), Left
),
8143 Make_Integer_Literal
(Loc
, 2 ** P2
- 1))));
8144 Analyze_And_Resolve
(N
, Typ
);
8149 -- Here for the full rewrite
8152 Tnn
: constant Entity_Id
:= Make_Temporary
(Sloc
(N
), 'T', N
);
8158 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Left
),
8159 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0));
8161 if not LOK
or else Rlo
< 0 then
8167 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Right
),
8168 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0)));
8172 Make_Object_Declaration
(Loc
,
8173 Defining_Identifier
=> Tnn
,
8174 Constant_Present
=> True,
8175 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
),
8179 Right_Opnd
=> Right
)));
8182 Make_If_Expression
(Loc
,
8183 Expressions
=> New_List
(
8185 New_Occurrence_Of
(Tnn
, Loc
),
8186 Make_If_Expression
(Loc
,
8188 Expressions
=> New_List
(
8190 Left_Opnd
=> New_Occurrence_Of
(Tnn
, Loc
),
8191 Right_Opnd
=> Make_Integer_Literal
(Loc
, 0)),
8192 Make_Integer_Literal
(Loc
, 0),
8194 Left_Opnd
=> New_Occurrence_Of
(Tnn
, Loc
),
8196 Duplicate_Subexpr_No_Checks
(Right
)))))));
8198 Analyze_And_Resolve
(N
, Typ
);
8203 -- Deal with annoying case of largest negative number mod minus one.
8204 -- Gigi may not handle this case correctly, because on some targets,
8205 -- the mod value is computed using a divide instruction which gives
8206 -- an overflow trap for this case.
8208 -- It would be a bit more efficient to figure out which targets
8209 -- this is really needed for, but in practice it is reasonable
8210 -- to do the following special check in all cases, since it means
8211 -- we get a clearer message, and also the overhead is minimal given
8212 -- that division is expensive in any case.
8214 -- In fact the check is quite easy, if the right operand is -1, then
8215 -- the mod value is always 0, and we can just ignore the left operand
8216 -- completely in this case.
8218 -- This only applies if we still have a mod operator. Skip if we
8219 -- have already rewritten this (e.g. in the case of eliminated
8220 -- overflow checks which have driven us into bignum mode).
8222 if Nkind
(N
) = N_Op_Mod
then
8224 -- The operand type may be private (e.g. in the expansion of an
8225 -- intrinsic operation) so we must use the underlying type to get
8226 -- the bounds, and convert the literals explicitly.
8230 (Type_Low_Bound
(Base_Type
(Underlying_Type
(Etype
(Left
)))));
8232 if ((not ROK
) or else (Rlo
<= (-1) and then (-1) <= Rhi
))
8233 and then ((not LOK
) or else (Llo
= LLB
))
8236 Make_If_Expression
(Loc
,
8237 Expressions
=> New_List
(
8239 Left_Opnd
=> Duplicate_Subexpr
(Right
),
8241 Unchecked_Convert_To
(Typ
,
8242 Make_Integer_Literal
(Loc
, -1))),
8243 Unchecked_Convert_To
(Typ
,
8244 Make_Integer_Literal
(Loc
, Uint_0
)),
8245 Relocate_Node
(N
))));
8247 Set_Analyzed
(Next
(Next
(First
(Expressions
(N
)))));
8248 Analyze_And_Resolve
(N
, Typ
);
8252 end Expand_N_Op_Mod
;
8254 --------------------------
8255 -- Expand_N_Op_Multiply --
8256 --------------------------
8258 procedure Expand_N_Op_Multiply
(N
: Node_Id
) is
8259 Loc
: constant Source_Ptr
:= Sloc
(N
);
8260 Lop
: constant Node_Id
:= Left_Opnd
(N
);
8261 Rop
: constant Node_Id
:= Right_Opnd
(N
);
8263 Lp2
: constant Boolean :=
8264 Nkind
(Lop
) = N_Op_Expon
and then Is_Power_Of_2_For_Shift
(Lop
);
8265 Rp2
: constant Boolean :=
8266 Nkind
(Rop
) = N_Op_Expon
and then Is_Power_Of_2_For_Shift
(Rop
);
8268 Ltyp
: constant Entity_Id
:= Etype
(Lop
);
8269 Rtyp
: constant Entity_Id
:= Etype
(Rop
);
8270 Typ
: Entity_Id
:= Etype
(N
);
8273 Binary_Op_Validity_Checks
(N
);
8275 -- Check for MINIMIZED/ELIMINATED overflow mode
8277 if Minimized_Eliminated_Overflow_Check
(N
) then
8278 Apply_Arithmetic_Overflow_Check
(N
);
8282 -- Special optimizations for integer types
8284 if Is_Integer_Type
(Typ
) then
8286 -- N * 0 = 0 for integer types
8288 if Compile_Time_Known_Value
(Rop
)
8289 and then Expr_Value
(Rop
) = Uint_0
8291 -- Call Remove_Side_Effects to ensure that any side effects in
8292 -- the ignored left operand (in particular function calls to
8293 -- user defined functions) are properly executed.
8295 Remove_Side_Effects
(Lop
);
8297 Rewrite
(N
, Make_Integer_Literal
(Loc
, Uint_0
));
8298 Analyze_And_Resolve
(N
, Typ
);
8302 -- Similar handling for 0 * N = 0
8304 if Compile_Time_Known_Value
(Lop
)
8305 and then Expr_Value
(Lop
) = Uint_0
8307 Remove_Side_Effects
(Rop
);
8308 Rewrite
(N
, Make_Integer_Literal
(Loc
, Uint_0
));
8309 Analyze_And_Resolve
(N
, Typ
);
8313 -- N * 1 = 1 * N = N for integer types
8315 -- This optimisation is not done if we are going to
8316 -- rewrite the product 1 * 2 ** N to a shift.
8318 if Compile_Time_Known_Value
(Rop
)
8319 and then Expr_Value
(Rop
) = Uint_1
8325 elsif Compile_Time_Known_Value
(Lop
)
8326 and then Expr_Value
(Lop
) = Uint_1
8334 -- Convert x * 2 ** y to Shift_Left (x, y). Note that the fact that
8335 -- Is_Power_Of_2_For_Shift is set means that we know that our left
8336 -- operand is an integer, as required for this to work.
8341 -- Convert 2 ** A * 2 ** B into 2 ** (A + B)
8345 Left_Opnd
=> Make_Integer_Literal
(Loc
, 2),
8348 Left_Opnd
=> Right_Opnd
(Lop
),
8349 Right_Opnd
=> Right_Opnd
(Rop
))));
8350 Analyze_And_Resolve
(N
, Typ
);
8354 -- If the result is modular, perform the reduction of the result
8357 if Is_Modular_Integer_Type
(Typ
)
8358 and then not Non_Binary_Modulus
(Typ
)
8363 Make_Op_Shift_Left
(Loc
,
8366 Convert_To
(Standard_Natural
, Right_Opnd
(Rop
))),
8368 Make_Integer_Literal
(Loc
, Modulus
(Typ
) - 1)));
8372 Make_Op_Shift_Left
(Loc
,
8375 Convert_To
(Standard_Natural
, Right_Opnd
(Rop
))));
8378 Analyze_And_Resolve
(N
, Typ
);
8382 -- Same processing for the operands the other way round
8385 if Is_Modular_Integer_Type
(Typ
)
8386 and then not Non_Binary_Modulus
(Typ
)
8391 Make_Op_Shift_Left
(Loc
,
8394 Convert_To
(Standard_Natural
, Right_Opnd
(Lop
))),
8396 Make_Integer_Literal
(Loc
, Modulus
(Typ
) - 1)));
8400 Make_Op_Shift_Left
(Loc
,
8403 Convert_To
(Standard_Natural
, Right_Opnd
(Lop
))));
8406 Analyze_And_Resolve
(N
, Typ
);
8410 -- Do required fixup of universal fixed operation
8412 if Typ
= Universal_Fixed
then
8413 Fixup_Universal_Fixed_Operation
(N
);
8417 -- Multiplications with fixed-point results
8419 if Is_Fixed_Point_Type
(Typ
) then
8421 -- No special processing if Treat_Fixed_As_Integer is set, since from
8422 -- a semantic point of view such operations are simply integer
8423 -- operations and will be treated that way.
8425 if not Treat_Fixed_As_Integer
(N
) then
8427 -- Case of fixed * integer => fixed
8429 if Is_Integer_Type
(Rtyp
) then
8430 Expand_Multiply_Fixed_By_Integer_Giving_Fixed
(N
);
8432 -- Case of integer * fixed => fixed
8434 elsif Is_Integer_Type
(Ltyp
) then
8435 Expand_Multiply_Integer_By_Fixed_Giving_Fixed
(N
);
8437 -- Case of fixed * fixed => fixed
8440 Expand_Multiply_Fixed_By_Fixed_Giving_Fixed
(N
);
8444 -- Other cases of multiplication of fixed-point operands. Again we
8445 -- exclude the cases where Treat_Fixed_As_Integer flag is set.
8447 elsif (Is_Fixed_Point_Type
(Ltyp
) or else Is_Fixed_Point_Type
(Rtyp
))
8448 and then not Treat_Fixed_As_Integer
(N
)
8450 if Is_Integer_Type
(Typ
) then
8451 Expand_Multiply_Fixed_By_Fixed_Giving_Integer
(N
);
8453 pragma Assert
(Is_Floating_Point_Type
(Typ
));
8454 Expand_Multiply_Fixed_By_Fixed_Giving_Float
(N
);
8457 -- Mixed-mode operations can appear in a non-static universal context,
8458 -- in which case the integer argument must be converted explicitly.
8460 elsif Typ
= Universal_Real
and then Is_Integer_Type
(Rtyp
) then
8461 Rewrite
(Rop
, Convert_To
(Universal_Real
, Relocate_Node
(Rop
)));
8462 Analyze_And_Resolve
(Rop
, Universal_Real
);
8464 elsif Typ
= Universal_Real
and then Is_Integer_Type
(Ltyp
) then
8465 Rewrite
(Lop
, Convert_To
(Universal_Real
, Relocate_Node
(Lop
)));
8466 Analyze_And_Resolve
(Lop
, Universal_Real
);
8468 -- Non-fixed point cases, check software overflow checking required
8470 elsif Is_Signed_Integer_Type
(Etype
(N
)) then
8471 Apply_Arithmetic_Overflow_Check
(N
);
8474 -- Overflow checks for floating-point if -gnateF mode active
8476 Check_Float_Op_Overflow
(N
);
8477 end Expand_N_Op_Multiply
;
8479 --------------------
8480 -- Expand_N_Op_Ne --
8481 --------------------
8483 procedure Expand_N_Op_Ne
(N
: Node_Id
) is
8484 Typ
: constant Entity_Id
:= Etype
(Left_Opnd
(N
));
8487 -- Case of elementary type with standard operator
8489 if Is_Elementary_Type
(Typ
)
8490 and then Sloc
(Entity
(N
)) = Standard_Location
8492 Binary_Op_Validity_Checks
(N
);
8494 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if
8495 -- means we no longer have a /= operation, we are all done.
8497 Expand_Compare_Minimize_Eliminate_Overflow
(N
);
8499 if Nkind
(N
) /= N_Op_Ne
then
8503 -- Boolean types (requiring handling of non-standard case)
8505 if Is_Boolean_Type
(Typ
) then
8506 Adjust_Condition
(Left_Opnd
(N
));
8507 Adjust_Condition
(Right_Opnd
(N
));
8508 Set_Etype
(N
, Standard_Boolean
);
8509 Adjust_Result_Type
(N
, Typ
);
8512 Rewrite_Comparison
(N
);
8514 -- For all cases other than elementary types, we rewrite node as the
8515 -- negation of an equality operation, and reanalyze. The equality to be
8516 -- used is defined in the same scope and has the same signature. This
8517 -- signature must be set explicitly since in an instance it may not have
8518 -- the same visibility as in the generic unit. This avoids duplicating
8519 -- or factoring the complex code for record/array equality tests etc.
8523 Loc
: constant Source_Ptr
:= Sloc
(N
);
8525 Ne
: constant Entity_Id
:= Entity
(N
);
8528 Binary_Op_Validity_Checks
(N
);
8534 Left_Opnd
=> Left_Opnd
(N
),
8535 Right_Opnd
=> Right_Opnd
(N
)));
8536 Set_Paren_Count
(Right_Opnd
(Neg
), 1);
8538 if Scope
(Ne
) /= Standard_Standard
then
8539 Set_Entity
(Right_Opnd
(Neg
), Corresponding_Equality
(Ne
));
8542 -- For navigation purposes, we want to treat the inequality as an
8543 -- implicit reference to the corresponding equality. Preserve the
8544 -- Comes_From_ source flag to generate proper Xref entries.
8546 Preserve_Comes_From_Source
(Neg
, N
);
8547 Preserve_Comes_From_Source
(Right_Opnd
(Neg
), N
);
8549 Analyze_And_Resolve
(N
, Standard_Boolean
);
8553 Optimize_Length_Comparison
(N
);
8556 ---------------------
8557 -- Expand_N_Op_Not --
8558 ---------------------
8560 -- If the argument is other than a Boolean array type, there is no special
8561 -- expansion required, except for dealing with validity checks, and non-
8562 -- standard boolean representations.
8564 -- For the packed array case, we call the special routine in Exp_Pakd,
8565 -- except that if the component size is greater than one, we use the
8566 -- standard routine generating a gruesome loop (it is so peculiar to have
8567 -- packed arrays with non-standard Boolean representations anyway, so it
8568 -- does not matter that we do not handle this case efficiently).
8570 -- For the unpacked array case (and for the special packed case where we
8571 -- have non standard Booleans, as discussed above), we generate and insert
8572 -- into the tree the following function definition:
8574 -- function Nnnn (A : arr) is
8577 -- for J in a'range loop
8578 -- B (J) := not A (J);
8583 -- Here arr is the actual subtype of the parameter (and hence always
8584 -- constrained). Then we replace the not with a call to this function.
8586 procedure Expand_N_Op_Not
(N
: Node_Id
) is
8587 Loc
: constant Source_Ptr
:= Sloc
(N
);
8588 Typ
: constant Entity_Id
:= Etype
(N
);
8597 Func_Name
: Entity_Id
;
8598 Loop_Statement
: Node_Id
;
8601 Unary_Op_Validity_Checks
(N
);
8603 -- For boolean operand, deal with non-standard booleans
8605 if Is_Boolean_Type
(Typ
) then
8606 Adjust_Condition
(Right_Opnd
(N
));
8607 Set_Etype
(N
, Standard_Boolean
);
8608 Adjust_Result_Type
(N
, Typ
);
8612 -- Only array types need any other processing
8614 if not Is_Array_Type
(Typ
) then
8618 -- Case of array operand. If bit packed with a component size of 1,
8619 -- handle it in Exp_Pakd if the operand is known to be aligned.
8621 if Is_Bit_Packed_Array
(Typ
)
8622 and then Component_Size
(Typ
) = 1
8623 and then not Is_Possibly_Unaligned_Object
(Right_Opnd
(N
))
8625 Expand_Packed_Not
(N
);
8629 -- Case of array operand which is not bit-packed. If the context is
8630 -- a safe assignment, call in-place operation, If context is a larger
8631 -- boolean expression in the context of a safe assignment, expansion is
8632 -- done by enclosing operation.
8634 Opnd
:= Relocate_Node
(Right_Opnd
(N
));
8635 Convert_To_Actual_Subtype
(Opnd
);
8636 Arr
:= Etype
(Opnd
);
8637 Ensure_Defined
(Arr
, N
);
8638 Silly_Boolean_Array_Not_Test
(N
, Arr
);
8640 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
8641 if Safe_In_Place_Array_Op
(Name
(Parent
(N
)), N
, Empty
) then
8642 Build_Boolean_Array_Proc_Call
(Parent
(N
), Opnd
, Empty
);
8645 -- Special case the negation of a binary operation
8647 elsif Nkind_In
(Opnd
, N_Op_And
, N_Op_Or
, N_Op_Xor
)
8648 and then Safe_In_Place_Array_Op
8649 (Name
(Parent
(N
)), Left_Opnd
(Opnd
), Right_Opnd
(Opnd
))
8651 Build_Boolean_Array_Proc_Call
(Parent
(N
), Opnd
, Empty
);
8655 elsif Nkind
(Parent
(N
)) in N_Binary_Op
8656 and then Nkind
(Parent
(Parent
(N
))) = N_Assignment_Statement
8659 Op1
: constant Node_Id
:= Left_Opnd
(Parent
(N
));
8660 Op2
: constant Node_Id
:= Right_Opnd
(Parent
(N
));
8661 Lhs
: constant Node_Id
:= Name
(Parent
(Parent
(N
)));
8664 if Safe_In_Place_Array_Op
(Lhs
, Op1
, Op2
) then
8666 -- (not A) op (not B) can be reduced to a single call
8668 if N
= Op1
and then Nkind
(Op2
) = N_Op_Not
then
8671 elsif N
= Op2
and then Nkind
(Op1
) = N_Op_Not
then
8674 -- A xor (not B) can also be special-cased
8676 elsif N
= Op2
and then Nkind
(Parent
(N
)) = N_Op_Xor
then
8683 A
:= Make_Defining_Identifier
(Loc
, Name_uA
);
8684 B
:= Make_Defining_Identifier
(Loc
, Name_uB
);
8685 J
:= Make_Defining_Identifier
(Loc
, Name_uJ
);
8688 Make_Indexed_Component
(Loc
,
8689 Prefix
=> New_Occurrence_Of
(A
, Loc
),
8690 Expressions
=> New_List
(New_Occurrence_Of
(J
, Loc
)));
8693 Make_Indexed_Component
(Loc
,
8694 Prefix
=> New_Occurrence_Of
(B
, Loc
),
8695 Expressions
=> New_List
(New_Occurrence_Of
(J
, Loc
)));
8698 Make_Implicit_Loop_Statement
(N
,
8699 Identifier
=> Empty
,
8702 Make_Iteration_Scheme
(Loc
,
8703 Loop_Parameter_Specification
=>
8704 Make_Loop_Parameter_Specification
(Loc
,
8705 Defining_Identifier
=> J
,
8706 Discrete_Subtype_Definition
=>
8707 Make_Attribute_Reference
(Loc
,
8708 Prefix
=> Make_Identifier
(Loc
, Chars
(A
)),
8709 Attribute_Name
=> Name_Range
))),
8711 Statements
=> New_List
(
8712 Make_Assignment_Statement
(Loc
,
8714 Expression
=> Make_Op_Not
(Loc
, A_J
))));
8716 Func_Name
:= Make_Temporary
(Loc
, 'N');
8717 Set_Is_Inlined
(Func_Name
);
8720 Make_Subprogram_Body
(Loc
,
8722 Make_Function_Specification
(Loc
,
8723 Defining_Unit_Name
=> Func_Name
,
8724 Parameter_Specifications
=> New_List
(
8725 Make_Parameter_Specification
(Loc
,
8726 Defining_Identifier
=> A
,
8727 Parameter_Type
=> New_Occurrence_Of
(Typ
, Loc
))),
8728 Result_Definition
=> New_Occurrence_Of
(Typ
, Loc
)),
8730 Declarations
=> New_List
(
8731 Make_Object_Declaration
(Loc
,
8732 Defining_Identifier
=> B
,
8733 Object_Definition
=> New_Occurrence_Of
(Arr
, Loc
))),
8735 Handled_Statement_Sequence
=>
8736 Make_Handled_Sequence_Of_Statements
(Loc
,
8737 Statements
=> New_List
(
8739 Make_Simple_Return_Statement
(Loc
,
8740 Expression
=> Make_Identifier
(Loc
, Chars
(B
)))))));
8743 Make_Function_Call
(Loc
,
8744 Name
=> New_Occurrence_Of
(Func_Name
, Loc
),
8745 Parameter_Associations
=> New_List
(Opnd
)));
8747 Analyze_And_Resolve
(N
, Typ
);
8748 end Expand_N_Op_Not
;
8750 --------------------
8751 -- Expand_N_Op_Or --
8752 --------------------
8754 procedure Expand_N_Op_Or
(N
: Node_Id
) is
8755 Typ
: constant Entity_Id
:= Etype
(N
);
8758 Binary_Op_Validity_Checks
(N
);
8760 if Is_Array_Type
(Etype
(N
)) then
8761 Expand_Boolean_Operator
(N
);
8763 elsif Is_Boolean_Type
(Etype
(N
)) then
8764 Adjust_Condition
(Left_Opnd
(N
));
8765 Adjust_Condition
(Right_Opnd
(N
));
8766 Set_Etype
(N
, Standard_Boolean
);
8767 Adjust_Result_Type
(N
, Typ
);
8769 elsif Is_Intrinsic_Subprogram
(Entity
(N
)) then
8770 Expand_Intrinsic_Call
(N
, Entity
(N
));
8775 ----------------------
8776 -- Expand_N_Op_Plus --
8777 ----------------------
8779 procedure Expand_N_Op_Plus
(N
: Node_Id
) is
8781 Unary_Op_Validity_Checks
(N
);
8783 -- Check for MINIMIZED/ELIMINATED overflow mode
8785 if Minimized_Eliminated_Overflow_Check
(N
) then
8786 Apply_Arithmetic_Overflow_Check
(N
);
8789 end Expand_N_Op_Plus
;
8791 ---------------------
8792 -- Expand_N_Op_Rem --
8793 ---------------------
8795 procedure Expand_N_Op_Rem
(N
: Node_Id
) is
8796 Loc
: constant Source_Ptr
:= Sloc
(N
);
8797 Typ
: constant Entity_Id
:= Etype
(N
);
8808 -- Set if corresponding operand can be negative
8810 pragma Unreferenced
(Hi
);
8813 Binary_Op_Validity_Checks
(N
);
8815 -- Check for MINIMIZED/ELIMINATED overflow mode
8817 if Minimized_Eliminated_Overflow_Check
(N
) then
8818 Apply_Arithmetic_Overflow_Check
(N
);
8822 if Is_Integer_Type
(Etype
(N
)) then
8823 Apply_Divide_Checks
(N
);
8825 -- All done if we don't have a REM any more, which can happen as a
8826 -- result of overflow expansion in MINIMIZED or ELIMINATED modes.
8828 if Nkind
(N
) /= N_Op_Rem
then
8833 -- Proceed with expansion of REM
8835 Left
:= Left_Opnd
(N
);
8836 Right
:= Right_Opnd
(N
);
8838 -- Apply optimization x rem 1 = 0. We don't really need that with gcc,
8839 -- but it is useful with other back ends (e.g. AAMP), and is certainly
8842 if Is_Integer_Type
(Etype
(N
))
8843 and then Compile_Time_Known_Value
(Right
)
8844 and then Expr_Value
(Right
) = Uint_1
8846 -- Call Remove_Side_Effects to ensure that any side effects in the
8847 -- ignored left operand (in particular function calls to user defined
8848 -- functions) are properly executed.
8850 Remove_Side_Effects
(Left
);
8852 Rewrite
(N
, Make_Integer_Literal
(Loc
, 0));
8853 Analyze_And_Resolve
(N
, Typ
);
8857 -- Deal with annoying case of largest negative number remainder minus
8858 -- one. Gigi may not handle this case correctly, because on some
8859 -- targets, the mod value is computed using a divide instruction
8860 -- which gives an overflow trap for this case.
8862 -- It would be a bit more efficient to figure out which targets this
8863 -- is really needed for, but in practice it is reasonable to do the
8864 -- following special check in all cases, since it means we get a clearer
8865 -- message, and also the overhead is minimal given that division is
8866 -- expensive in any case.
8868 -- In fact the check is quite easy, if the right operand is -1, then
8869 -- the remainder is always 0, and we can just ignore the left operand
8870 -- completely in this case.
8872 Determine_Range
(Right
, OK
, Lo
, Hi
, Assume_Valid
=> True);
8873 Lneg
:= (not OK
) or else Lo
< 0;
8875 Determine_Range
(Left
, OK
, Lo
, Hi
, Assume_Valid
=> True);
8876 Rneg
:= (not OK
) or else Lo
< 0;
8878 -- We won't mess with trying to find out if the left operand can really
8879 -- be the largest negative number (that's a pain in the case of private
8880 -- types and this is really marginal). We will just assume that we need
8881 -- the test if the left operand can be negative at all.
8883 if Lneg
and Rneg
then
8885 Make_If_Expression
(Loc
,
8886 Expressions
=> New_List
(
8888 Left_Opnd
=> Duplicate_Subexpr
(Right
),
8890 Unchecked_Convert_To
(Typ
, Make_Integer_Literal
(Loc
, -1))),
8892 Unchecked_Convert_To
(Typ
,
8893 Make_Integer_Literal
(Loc
, Uint_0
)),
8895 Relocate_Node
(N
))));
8897 Set_Analyzed
(Next
(Next
(First
(Expressions
(N
)))));
8898 Analyze_And_Resolve
(N
, Typ
);
8900 end Expand_N_Op_Rem
;
8902 -----------------------------
8903 -- Expand_N_Op_Rotate_Left --
8904 -----------------------------
8906 procedure Expand_N_Op_Rotate_Left
(N
: Node_Id
) is
8908 Binary_Op_Validity_Checks
(N
);
8910 -- If we are in Modify_Tree_For_C mode, there is no rotate left in C,
8911 -- so we rewrite in terms of logical shifts
8913 -- Shift_Left (Num, Bits) or Shift_Right (num, Esize - Bits)
8915 -- where Bits is the shift count mod Esize (the mod operation here
8916 -- deals with ludicrous large shift counts, which are apparently OK).
8918 -- What about non-binary modulus ???
8921 Loc
: constant Source_Ptr
:= Sloc
(N
);
8922 Rtp
: constant Entity_Id
:= Etype
(Right_Opnd
(N
));
8923 Typ
: constant Entity_Id
:= Etype
(N
);
8926 if Modify_Tree_For_C
then
8927 Rewrite
(Right_Opnd
(N
),
8929 Left_Opnd
=> Relocate_Node
(Right_Opnd
(N
)),
8930 Right_Opnd
=> Make_Integer_Literal
(Loc
, Esize
(Typ
))));
8932 Analyze_And_Resolve
(Right_Opnd
(N
), Rtp
);
8937 Make_Op_Shift_Left
(Loc
,
8938 Left_Opnd
=> Left_Opnd
(N
),
8939 Right_Opnd
=> Right_Opnd
(N
)),
8942 Make_Op_Shift_Right
(Loc
,
8943 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Left_Opnd
(N
)),
8945 Make_Op_Subtract
(Loc
,
8946 Left_Opnd
=> Make_Integer_Literal
(Loc
, Esize
(Typ
)),
8948 Duplicate_Subexpr_No_Checks
(Right_Opnd
(N
))))));
8950 Analyze_And_Resolve
(N
, Typ
);
8953 end Expand_N_Op_Rotate_Left
;
8955 ------------------------------
8956 -- Expand_N_Op_Rotate_Right --
8957 ------------------------------
8959 procedure Expand_N_Op_Rotate_Right
(N
: Node_Id
) is
8961 Binary_Op_Validity_Checks
(N
);
8963 -- If we are in Modify_Tree_For_C mode, there is no rotate right in C,
8964 -- so we rewrite in terms of logical shifts
8966 -- Shift_Right (Num, Bits) or Shift_Left (num, Esize - Bits)
8968 -- where Bits is the shift count mod Esize (the mod operation here
8969 -- deals with ludicrous large shift counts, which are apparently OK).
8971 -- What about non-binary modulus ???
8974 Loc
: constant Source_Ptr
:= Sloc
(N
);
8975 Rtp
: constant Entity_Id
:= Etype
(Right_Opnd
(N
));
8976 Typ
: constant Entity_Id
:= Etype
(N
);
8979 Rewrite
(Right_Opnd
(N
),
8981 Left_Opnd
=> Relocate_Node
(Right_Opnd
(N
)),
8982 Right_Opnd
=> Make_Integer_Literal
(Loc
, Esize
(Typ
))));
8984 Analyze_And_Resolve
(Right_Opnd
(N
), Rtp
);
8986 if Modify_Tree_For_C
then
8990 Make_Op_Shift_Right
(Loc
,
8991 Left_Opnd
=> Left_Opnd
(N
),
8992 Right_Opnd
=> Right_Opnd
(N
)),
8995 Make_Op_Shift_Left
(Loc
,
8996 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Left_Opnd
(N
)),
8998 Make_Op_Subtract
(Loc
,
8999 Left_Opnd
=> Make_Integer_Literal
(Loc
, Esize
(Typ
)),
9001 Duplicate_Subexpr_No_Checks
(Right_Opnd
(N
))))));
9003 Analyze_And_Resolve
(N
, Typ
);
9006 end Expand_N_Op_Rotate_Right
;
9008 ----------------------------
9009 -- Expand_N_Op_Shift_Left --
9010 ----------------------------
9012 -- Note: nothing in this routine depends on left as opposed to right shifts
9013 -- so we share the routine for expanding shift right operations.
9015 procedure Expand_N_Op_Shift_Left
(N
: Node_Id
) is
9017 Binary_Op_Validity_Checks
(N
);
9019 -- If we are in Modify_Tree_For_C mode, then ensure that the right
9020 -- operand is not greater than the word size (since that would not
9021 -- be defined properly by the corresponding C shift operator).
9023 if Modify_Tree_For_C
then
9025 Right
: constant Node_Id
:= Right_Opnd
(N
);
9026 Loc
: constant Source_Ptr
:= Sloc
(Right
);
9027 Typ
: constant Entity_Id
:= Etype
(N
);
9028 Siz
: constant Uint
:= Esize
(Typ
);
9035 if Compile_Time_Known_Value
(Right
) then
9036 if Expr_Value
(Right
) >= Siz
then
9037 Rewrite
(N
, Make_Integer_Literal
(Loc
, 0));
9038 Analyze_And_Resolve
(N
, Typ
);
9041 -- Not compile time known, find range
9044 Determine_Range
(Right
, OK
, Lo
, Hi
, Assume_Valid
=> True);
9046 -- Nothing to do if known to be OK range, otherwise expand
9048 if not OK
or else Hi
>= Siz
then
9050 -- Prevent recursion on copy of shift node
9052 Orig
:= Relocate_Node
(N
);
9053 Set_Analyzed
(Orig
);
9055 -- Now do the rewrite
9058 Make_If_Expression
(Loc
,
9059 Expressions
=> New_List
(
9061 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Right
),
9062 Right_Opnd
=> Make_Integer_Literal
(Loc
, Siz
)),
9063 Make_Integer_Literal
(Loc
, 0),
9065 Analyze_And_Resolve
(N
, Typ
);
9070 end Expand_N_Op_Shift_Left
;
9072 -----------------------------
9073 -- Expand_N_Op_Shift_Right --
9074 -----------------------------
9076 procedure Expand_N_Op_Shift_Right
(N
: Node_Id
) is
9078 -- Share shift left circuit
9080 Expand_N_Op_Shift_Left
(N
);
9081 end Expand_N_Op_Shift_Right
;
9083 ----------------------------------------
9084 -- Expand_N_Op_Shift_Right_Arithmetic --
9085 ----------------------------------------
9087 procedure Expand_N_Op_Shift_Right_Arithmetic
(N
: Node_Id
) is
9089 Binary_Op_Validity_Checks
(N
);
9091 -- If we are in Modify_Tree_For_C mode, there is no shift right
9092 -- arithmetic in C, so we rewrite in terms of logical shifts.
9094 -- Shift_Right (Num, Bits) or
9096 -- then not (Shift_Right (Mask, bits))
9099 -- Here Mask is all 1 bits (2**size - 1), and Sign is 2**(size - 1)
9101 -- Note: in almost all C compilers it would work to just shift a
9102 -- signed integer right, but it's undefined and we cannot rely on it.
9104 -- Note: the above works fine for shift counts greater than or equal
9105 -- to the word size, since in this case (not (Shift_Right (Mask, bits)))
9106 -- generates all 1'bits.
9108 -- What about non-binary modulus ???
9111 Loc
: constant Source_Ptr
:= Sloc
(N
);
9112 Typ
: constant Entity_Id
:= Etype
(N
);
9113 Sign
: constant Uint
:= 2 ** (Esize
(Typ
) - 1);
9114 Mask
: constant Uint
:= (2 ** Esize
(Typ
)) - 1;
9115 Left
: constant Node_Id
:= Left_Opnd
(N
);
9116 Right
: constant Node_Id
:= Right_Opnd
(N
);
9120 if Modify_Tree_For_C
then
9122 -- Here if not (Shift_Right (Mask, bits)) can be computed at
9123 -- compile time as a single constant.
9125 if Compile_Time_Known_Value
(Right
) then
9127 Val
: constant Uint
:= Expr_Value
(Right
);
9130 if Val
>= Esize
(Typ
) then
9131 Maskx
:= Make_Integer_Literal
(Loc
, Mask
);
9135 Make_Integer_Literal
(Loc
,
9136 Intval
=> Mask
- (Mask
/ (2 ** Expr_Value
(Right
))));
9144 Make_Op_Shift_Right
(Loc
,
9145 Left_Opnd
=> Make_Integer_Literal
(Loc
, Mask
),
9146 Right_Opnd
=> Duplicate_Subexpr_No_Checks
(Right
)));
9149 -- Now do the rewrite
9154 Make_Op_Shift_Right
(Loc
,
9156 Right_Opnd
=> Right
),
9158 Make_If_Expression
(Loc
,
9159 Expressions
=> New_List
(
9161 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Left
),
9162 Right_Opnd
=> Make_Integer_Literal
(Loc
, Sign
)),
9164 Make_Integer_Literal
(Loc
, 0)))));
9165 Analyze_And_Resolve
(N
, Typ
);
9168 end Expand_N_Op_Shift_Right_Arithmetic
;
9170 --------------------------
9171 -- Expand_N_Op_Subtract --
9172 --------------------------
9174 procedure Expand_N_Op_Subtract
(N
: Node_Id
) is
9175 Typ
: constant Entity_Id
:= Etype
(N
);
9178 Binary_Op_Validity_Checks
(N
);
9180 -- Check for MINIMIZED/ELIMINATED overflow mode
9182 if Minimized_Eliminated_Overflow_Check
(N
) then
9183 Apply_Arithmetic_Overflow_Check
(N
);
9187 -- N - 0 = N for integer types
9189 if Is_Integer_Type
(Typ
)
9190 and then Compile_Time_Known_Value
(Right_Opnd
(N
))
9191 and then Expr_Value
(Right_Opnd
(N
)) = 0
9193 Rewrite
(N
, Left_Opnd
(N
));
9197 -- Arithmetic overflow checks for signed integer/fixed point types
9199 if Is_Signed_Integer_Type
(Typ
) or else Is_Fixed_Point_Type
(Typ
) then
9200 Apply_Arithmetic_Overflow_Check
(N
);
9203 -- Overflow checks for floating-point if -gnateF mode active
9205 Check_Float_Op_Overflow
(N
);
9206 end Expand_N_Op_Subtract
;
9208 ---------------------
9209 -- Expand_N_Op_Xor --
9210 ---------------------
9212 procedure Expand_N_Op_Xor
(N
: Node_Id
) is
9213 Typ
: constant Entity_Id
:= Etype
(N
);
9216 Binary_Op_Validity_Checks
(N
);
9218 if Is_Array_Type
(Etype
(N
)) then
9219 Expand_Boolean_Operator
(N
);
9221 elsif Is_Boolean_Type
(Etype
(N
)) then
9222 Adjust_Condition
(Left_Opnd
(N
));
9223 Adjust_Condition
(Right_Opnd
(N
));
9224 Set_Etype
(N
, Standard_Boolean
);
9225 Adjust_Result_Type
(N
, Typ
);
9227 elsif Is_Intrinsic_Subprogram
(Entity
(N
)) then
9228 Expand_Intrinsic_Call
(N
, Entity
(N
));
9231 end Expand_N_Op_Xor
;
9233 ----------------------
9234 -- Expand_N_Or_Else --
9235 ----------------------
9237 procedure Expand_N_Or_Else
(N
: Node_Id
)
9238 renames Expand_Short_Circuit_Operator
;
9240 -----------------------------------
9241 -- Expand_N_Qualified_Expression --
9242 -----------------------------------
9244 procedure Expand_N_Qualified_Expression
(N
: Node_Id
) is
9245 Operand
: constant Node_Id
:= Expression
(N
);
9246 Target_Type
: constant Entity_Id
:= Entity
(Subtype_Mark
(N
));
9249 -- Do validity check if validity checking operands
9251 if Validity_Checks_On
and Validity_Check_Operands
then
9252 Ensure_Valid
(Operand
);
9255 -- Apply possible constraint check
9257 Apply_Constraint_Check
(Operand
, Target_Type
, No_Sliding
=> True);
9259 if Do_Range_Check
(Operand
) then
9260 Set_Do_Range_Check
(Operand
, False);
9261 Generate_Range_Check
(Operand
, Target_Type
, CE_Range_Check_Failed
);
9263 end Expand_N_Qualified_Expression
;
9265 ------------------------------------
9266 -- Expand_N_Quantified_Expression --
9267 ------------------------------------
9271 -- for all X in range => Cond
9276 -- for X in range loop
9283 -- Similarly, an existentially quantified expression:
9285 -- for some X in range => Cond
9290 -- for X in range loop
9297 -- In both cases, the iteration may be over a container in which case it is
9298 -- given by an iterator specification, not a loop parameter specification.
9300 procedure Expand_N_Quantified_Expression
(N
: Node_Id
) is
9301 Actions
: constant List_Id
:= New_List
;
9302 For_All
: constant Boolean := All_Present
(N
);
9303 Iter_Spec
: constant Node_Id
:= Iterator_Specification
(N
);
9304 Loc
: constant Source_Ptr
:= Sloc
(N
);
9305 Loop_Spec
: constant Node_Id
:= Loop_Parameter_Specification
(N
);
9312 -- Create the declaration of the flag which tracks the status of the
9313 -- quantified expression. Generate:
9315 -- Flag : Boolean := (True | False);
9317 Flag
:= Make_Temporary
(Loc
, 'T', N
);
9320 Make_Object_Declaration
(Loc
,
9321 Defining_Identifier
=> Flag
,
9322 Object_Definition
=> New_Occurrence_Of
(Standard_Boolean
, Loc
),
9324 New_Occurrence_Of
(Boolean_Literals
(For_All
), Loc
)));
9326 -- Construct the circuitry which tracks the status of the quantified
9327 -- expression. Generate:
9329 -- if [not] Cond then
9330 -- Flag := (False | True);
9334 Cond
:= Relocate_Node
(Condition
(N
));
9337 Cond
:= Make_Op_Not
(Loc
, Cond
);
9341 Make_Implicit_If_Statement
(N
,
9343 Then_Statements
=> New_List
(
9344 Make_Assignment_Statement
(Loc
,
9345 Name
=> New_Occurrence_Of
(Flag
, Loc
),
9347 New_Occurrence_Of
(Boolean_Literals
(not For_All
), Loc
)),
9348 Make_Exit_Statement
(Loc
))));
9350 -- Build the loop equivalent of the quantified expression
9352 if Present
(Iter_Spec
) then
9354 Make_Iteration_Scheme
(Loc
,
9355 Iterator_Specification
=> Iter_Spec
);
9358 Make_Iteration_Scheme
(Loc
,
9359 Loop_Parameter_Specification
=> Loop_Spec
);
9363 Make_Loop_Statement
(Loc
,
9364 Iteration_Scheme
=> Scheme
,
9365 Statements
=> Stmts
,
9366 End_Label
=> Empty
));
9368 -- Transform the quantified expression
9371 Make_Expression_With_Actions
(Loc
,
9372 Expression
=> New_Occurrence_Of
(Flag
, Loc
),
9373 Actions
=> Actions
));
9374 Analyze_And_Resolve
(N
, Standard_Boolean
);
9375 end Expand_N_Quantified_Expression
;
9377 ---------------------------------
9378 -- Expand_N_Selected_Component --
9379 ---------------------------------
9381 procedure Expand_N_Selected_Component
(N
: Node_Id
) is
9382 Loc
: constant Source_Ptr
:= Sloc
(N
);
9383 Par
: constant Node_Id
:= Parent
(N
);
9384 P
: constant Node_Id
:= Prefix
(N
);
9385 S
: constant Node_Id
:= Selector_Name
(N
);
9386 Ptyp
: Entity_Id
:= Underlying_Type
(Etype
(P
));
9392 function In_Left_Hand_Side
(Comp
: Node_Id
) return Boolean;
9393 -- Gigi needs a temporary for prefixes that depend on a discriminant,
9394 -- unless the context of an assignment can provide size information.
9395 -- Don't we have a general routine that does this???
9397 function Is_Subtype_Declaration
return Boolean;
9398 -- The replacement of a discriminant reference by its value is required
9399 -- if this is part of the initialization of an temporary generated by a
9400 -- change of representation. This shows up as the construction of a
9401 -- discriminant constraint for a subtype declared at the same point as
9402 -- the entity in the prefix of the selected component. We recognize this
9403 -- case when the context of the reference is:
9404 -- subtype ST is T(Obj.D);
9405 -- where the entity for Obj comes from source, and ST has the same sloc.
9407 -----------------------
9408 -- In_Left_Hand_Side --
9409 -----------------------
9411 function In_Left_Hand_Side
(Comp
: Node_Id
) return Boolean is
9413 return (Nkind
(Parent
(Comp
)) = N_Assignment_Statement
9414 and then Comp
= Name
(Parent
(Comp
)))
9415 or else (Present
(Parent
(Comp
))
9416 and then Nkind
(Parent
(Comp
)) in N_Subexpr
9417 and then In_Left_Hand_Side
(Parent
(Comp
)));
9418 end In_Left_Hand_Side
;
9420 -----------------------------
9421 -- Is_Subtype_Declaration --
9422 -----------------------------
9424 function Is_Subtype_Declaration
return Boolean is
9425 Par
: constant Node_Id
:= Parent
(N
);
9428 Nkind
(Par
) = N_Index_Or_Discriminant_Constraint
9429 and then Nkind
(Parent
(Parent
(Par
))) = N_Subtype_Declaration
9430 and then Comes_From_Source
(Entity
(Prefix
(N
)))
9431 and then Sloc
(Par
) = Sloc
(Entity
(Prefix
(N
)));
9432 end Is_Subtype_Declaration
;
9434 -- Start of processing for Expand_N_Selected_Component
9437 -- Insert explicit dereference if required
9439 if Is_Access_Type
(Ptyp
) then
9441 -- First set prefix type to proper access type, in case it currently
9442 -- has a private (non-access) view of this type.
9444 Set_Etype
(P
, Ptyp
);
9446 Insert_Explicit_Dereference
(P
);
9447 Analyze_And_Resolve
(P
, Designated_Type
(Ptyp
));
9449 if Ekind
(Etype
(P
)) = E_Private_Subtype
9450 and then Is_For_Access_Subtype
(Etype
(P
))
9452 Set_Etype
(P
, Base_Type
(Etype
(P
)));
9458 -- Deal with discriminant check required
9460 if Do_Discriminant_Check
(N
) then
9461 if Present
(Discriminant_Checking_Func
9462 (Original_Record_Component
(Entity
(S
))))
9464 -- Present the discriminant checking function to the backend, so
9465 -- that it can inline the call to the function.
9468 (Discriminant_Checking_Func
9469 (Original_Record_Component
(Entity
(S
))));
9471 -- Now reset the flag and generate the call
9473 Set_Do_Discriminant_Check
(N
, False);
9474 Generate_Discriminant_Check
(N
);
9476 -- In the case of Unchecked_Union, no discriminant checking is
9477 -- actually performed.
9480 Set_Do_Discriminant_Check
(N
, False);
9484 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
9485 -- function, then additional actuals must be passed.
9487 if Ada_Version
>= Ada_2005
9488 and then Is_Build_In_Place_Function_Call
(P
)
9490 Make_Build_In_Place_Call_In_Anonymous_Context
(P
);
9493 -- Gigi cannot handle unchecked conversions that are the prefix of a
9494 -- selected component with discriminants. This must be checked during
9495 -- expansion, because during analysis the type of the selector is not
9496 -- known at the point the prefix is analyzed. If the conversion is the
9497 -- target of an assignment, then we cannot force the evaluation.
9499 if Nkind
(Prefix
(N
)) = N_Unchecked_Type_Conversion
9500 and then Has_Discriminants
(Etype
(N
))
9501 and then not In_Left_Hand_Side
(N
)
9503 Force_Evaluation
(Prefix
(N
));
9506 -- Remaining processing applies only if selector is a discriminant
9508 if Ekind
(Entity
(Selector_Name
(N
))) = E_Discriminant
then
9510 -- If the selector is a discriminant of a constrained record type,
9511 -- we may be able to rewrite the expression with the actual value
9512 -- of the discriminant, a useful optimization in some cases.
9514 if Is_Record_Type
(Ptyp
)
9515 and then Has_Discriminants
(Ptyp
)
9516 and then Is_Constrained
(Ptyp
)
9518 -- Do this optimization for discrete types only, and not for
9519 -- access types (access discriminants get us into trouble).
9521 if not Is_Discrete_Type
(Etype
(N
)) then
9524 -- Don't do this on the left hand of an assignment statement.
9525 -- Normally one would think that references like this would not
9526 -- occur, but they do in generated code, and mean that we really
9527 -- do want to assign the discriminant.
9529 elsif Nkind
(Par
) = N_Assignment_Statement
9530 and then Name
(Par
) = N
9534 -- Don't do this optimization for the prefix of an attribute or
9535 -- the name of an object renaming declaration since these are
9536 -- contexts where we do not want the value anyway.
9538 elsif (Nkind
(Par
) = N_Attribute_Reference
9539 and then Prefix
(Par
) = N
)
9540 or else Is_Renamed_Object
(N
)
9544 -- Don't do this optimization if we are within the code for a
9545 -- discriminant check, since the whole point of such a check may
9546 -- be to verify the condition on which the code below depends.
9548 elsif Is_In_Discriminant_Check
(N
) then
9551 -- Green light to see if we can do the optimization. There is
9552 -- still one condition that inhibits the optimization below but
9553 -- now is the time to check the particular discriminant.
9556 -- Loop through discriminants to find the matching discriminant
9557 -- constraint to see if we can copy it.
9559 Disc
:= First_Discriminant
(Ptyp
);
9560 Dcon
:= First_Elmt
(Discriminant_Constraint
(Ptyp
));
9561 Discr_Loop
: while Present
(Dcon
) loop
9562 Dval
:= Node
(Dcon
);
9564 -- Check if this is the matching discriminant and if the
9565 -- discriminant value is simple enough to make sense to
9566 -- copy. We don't want to copy complex expressions, and
9567 -- indeed to do so can cause trouble (before we put in
9568 -- this guard, a discriminant expression containing an
9569 -- AND THEN was copied, causing problems for coverage
9572 -- However, if the reference is part of the initialization
9573 -- code generated for an object declaration, we must use
9574 -- the discriminant value from the subtype constraint,
9575 -- because the selected component may be a reference to the
9576 -- object being initialized, whose discriminant is not yet
9577 -- set. This only happens in complex cases involving changes
9578 -- or representation.
9580 if Disc
= Entity
(Selector_Name
(N
))
9581 and then (Is_Entity_Name
(Dval
)
9582 or else Compile_Time_Known_Value
(Dval
)
9583 or else Is_Subtype_Declaration
)
9585 -- Here we have the matching discriminant. Check for
9586 -- the case of a discriminant of a component that is
9587 -- constrained by an outer discriminant, which cannot
9588 -- be optimized away.
9590 if Denotes_Discriminant
9591 (Dval
, Check_Concurrent
=> True)
9595 elsif Nkind
(Original_Node
(Dval
)) = N_Selected_Component
9597 Denotes_Discriminant
9598 (Selector_Name
(Original_Node
(Dval
)), True)
9602 -- Do not retrieve value if constraint is not static. It
9603 -- is generally not useful, and the constraint may be a
9604 -- rewritten outer discriminant in which case it is in
9607 elsif Is_Entity_Name
(Dval
)
9609 Nkind
(Parent
(Entity
(Dval
))) = N_Object_Declaration
9610 and then Present
(Expression
(Parent
(Entity
(Dval
))))
9612 Is_OK_Static_Expression
9613 (Expression
(Parent
(Entity
(Dval
))))
9617 -- In the context of a case statement, the expression may
9618 -- have the base type of the discriminant, and we need to
9619 -- preserve the constraint to avoid spurious errors on
9622 elsif Nkind
(Parent
(N
)) = N_Case_Statement
9623 and then Etype
(Dval
) /= Etype
(Disc
)
9626 Make_Qualified_Expression
(Loc
,
9628 New_Occurrence_Of
(Etype
(Disc
), Loc
),
9630 New_Copy_Tree
(Dval
)));
9631 Analyze_And_Resolve
(N
, Etype
(Disc
));
9633 -- In case that comes out as a static expression,
9634 -- reset it (a selected component is never static).
9636 Set_Is_Static_Expression
(N
, False);
9639 -- Otherwise we can just copy the constraint, but the
9640 -- result is certainly not static. In some cases the
9641 -- discriminant constraint has been analyzed in the
9642 -- context of the original subtype indication, but for
9643 -- itypes the constraint might not have been analyzed
9644 -- yet, and this must be done now.
9647 Rewrite
(N
, New_Copy_Tree
(Dval
));
9648 Analyze_And_Resolve
(N
);
9649 Set_Is_Static_Expression
(N
, False);
9655 Next_Discriminant
(Disc
);
9656 end loop Discr_Loop
;
9658 -- Note: the above loop should always find a matching
9659 -- discriminant, but if it does not, we just missed an
9660 -- optimization due to some glitch (perhaps a previous
9661 -- error), so ignore.
9666 -- The only remaining processing is in the case of a discriminant of
9667 -- a concurrent object, where we rewrite the prefix to denote the
9668 -- corresponding record type. If the type is derived and has renamed
9669 -- discriminants, use corresponding discriminant, which is the one
9670 -- that appears in the corresponding record.
9672 if not Is_Concurrent_Type
(Ptyp
) then
9676 Disc
:= Entity
(Selector_Name
(N
));
9678 if Is_Derived_Type
(Ptyp
)
9679 and then Present
(Corresponding_Discriminant
(Disc
))
9681 Disc
:= Corresponding_Discriminant
(Disc
);
9685 Make_Selected_Component
(Loc
,
9687 Unchecked_Convert_To
(Corresponding_Record_Type
(Ptyp
),
9689 Selector_Name
=> Make_Identifier
(Loc
, Chars
(Disc
)));
9695 -- Set Atomic_Sync_Required if necessary for atomic component
9697 if Nkind
(N
) = N_Selected_Component
then
9699 E
: constant Entity_Id
:= Entity
(Selector_Name
(N
));
9703 -- If component is atomic, but type is not, setting depends on
9704 -- disable/enable state for the component.
9706 if Is_Atomic
(E
) and then not Is_Atomic
(Etype
(E
)) then
9707 Set
:= not Atomic_Synchronization_Disabled
(E
);
9709 -- If component is not atomic, but its type is atomic, setting
9710 -- depends on disable/enable state for the type.
9712 elsif not Is_Atomic
(E
) and then Is_Atomic
(Etype
(E
)) then
9713 Set
:= not Atomic_Synchronization_Disabled
(Etype
(E
));
9715 -- If both component and type are atomic, we disable if either
9716 -- component or its type have sync disabled.
9718 elsif Is_Atomic
(E
) and then Is_Atomic
(Etype
(E
)) then
9719 Set
:= (not Atomic_Synchronization_Disabled
(E
))
9721 (not Atomic_Synchronization_Disabled
(Etype
(E
)));
9727 -- Set flag if required
9730 Activate_Atomic_Synchronization
(N
);
9734 end Expand_N_Selected_Component
;
9736 --------------------
9737 -- Expand_N_Slice --
9738 --------------------
9740 procedure Expand_N_Slice
(N
: Node_Id
) is
9741 Loc
: constant Source_Ptr
:= Sloc
(N
);
9742 Typ
: constant Entity_Id
:= Etype
(N
);
9744 function Is_Procedure_Actual
(N
: Node_Id
) return Boolean;
9745 -- Check whether the argument is an actual for a procedure call, in
9746 -- which case the expansion of a bit-packed slice is deferred until the
9747 -- call itself is expanded. The reason this is required is that we might
9748 -- have an IN OUT or OUT parameter, and the copy out is essential, and
9749 -- that copy out would be missed if we created a temporary here in
9750 -- Expand_N_Slice. Note that we don't bother to test specifically for an
9751 -- IN OUT or OUT mode parameter, since it is a bit tricky to do, and it
9752 -- is harmless to defer expansion in the IN case, since the call
9753 -- processing will still generate the appropriate copy in operation,
9754 -- which will take care of the slice.
9756 procedure Make_Temporary_For_Slice
;
9757 -- Create a named variable for the value of the slice, in cases where
9758 -- the back-end cannot handle it properly, e.g. when packed types or
9759 -- unaligned slices are involved.
9761 -------------------------
9762 -- Is_Procedure_Actual --
9763 -------------------------
9765 function Is_Procedure_Actual
(N
: Node_Id
) return Boolean is
9766 Par
: Node_Id
:= Parent
(N
);
9770 -- If our parent is a procedure call we can return
9772 if Nkind
(Par
) = N_Procedure_Call_Statement
then
9775 -- If our parent is a type conversion, keep climbing the tree,
9776 -- since a type conversion can be a procedure actual. Also keep
9777 -- climbing if parameter association or a qualified expression,
9778 -- since these are additional cases that do can appear on
9779 -- procedure actuals.
9781 elsif Nkind_In
(Par
, N_Type_Conversion
,
9782 N_Parameter_Association
,
9783 N_Qualified_Expression
)
9785 Par
:= Parent
(Par
);
9787 -- Any other case is not what we are looking for
9793 end Is_Procedure_Actual
;
9795 ------------------------------
9796 -- Make_Temporary_For_Slice --
9797 ------------------------------
9799 procedure Make_Temporary_For_Slice
is
9800 Ent
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T', N
);
9805 Make_Object_Declaration
(Loc
,
9806 Defining_Identifier
=> Ent
,
9807 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
));
9809 Set_No_Initialization
(Decl
);
9811 Insert_Actions
(N
, New_List
(
9813 Make_Assignment_Statement
(Loc
,
9814 Name
=> New_Occurrence_Of
(Ent
, Loc
),
9815 Expression
=> Relocate_Node
(N
))));
9817 Rewrite
(N
, New_Occurrence_Of
(Ent
, Loc
));
9818 Analyze_And_Resolve
(N
, Typ
);
9819 end Make_Temporary_For_Slice
;
9823 Pref
: constant Node_Id
:= Prefix
(N
);
9824 Pref_Typ
: Entity_Id
:= Etype
(Pref
);
9826 -- Start of processing for Expand_N_Slice
9829 -- Special handling for access types
9831 if Is_Access_Type
(Pref_Typ
) then
9832 Pref_Typ
:= Designated_Type
(Pref_Typ
);
9835 Make_Explicit_Dereference
(Sloc
(N
),
9836 Prefix
=> Relocate_Node
(Pref
)));
9838 Analyze_And_Resolve
(Pref
, Pref_Typ
);
9841 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
9842 -- function, then additional actuals must be passed.
9844 if Ada_Version
>= Ada_2005
9845 and then Is_Build_In_Place_Function_Call
(Pref
)
9847 Make_Build_In_Place_Call_In_Anonymous_Context
(Pref
);
9850 -- The remaining case to be handled is packed slices. We can leave
9851 -- packed slices as they are in the following situations:
9853 -- 1. Right or left side of an assignment (we can handle this
9854 -- situation correctly in the assignment statement expansion).
9856 -- 2. Prefix of indexed component (the slide is optimized away in this
9857 -- case, see the start of Expand_N_Slice.)
9859 -- 3. Object renaming declaration, since we want the name of the
9860 -- slice, not the value.
9862 -- 4. Argument to procedure call, since copy-in/copy-out handling may
9863 -- be required, and this is handled in the expansion of call
9866 -- 5. Prefix of an address attribute (this is an error which is caught
9867 -- elsewhere, and the expansion would interfere with generating the
9870 if not Is_Packed
(Typ
) then
9872 -- Apply transformation for actuals of a function call, where
9873 -- Expand_Actuals is not used.
9875 if Nkind
(Parent
(N
)) = N_Function_Call
9876 and then Is_Possibly_Unaligned_Slice
(N
)
9878 Make_Temporary_For_Slice
;
9881 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
9882 or else (Nkind
(Parent
(Parent
(N
))) = N_Assignment_Statement
9883 and then Parent
(N
) = Name
(Parent
(Parent
(N
))))
9887 elsif Nkind
(Parent
(N
)) = N_Indexed_Component
9888 or else Is_Renamed_Object
(N
)
9889 or else Is_Procedure_Actual
(N
)
9893 elsif Nkind
(Parent
(N
)) = N_Attribute_Reference
9894 and then Attribute_Name
(Parent
(N
)) = Name_Address
9899 Make_Temporary_For_Slice
;
9903 ------------------------------
9904 -- Expand_N_Type_Conversion --
9905 ------------------------------
9907 procedure Expand_N_Type_Conversion
(N
: Node_Id
) is
9908 Loc
: constant Source_Ptr
:= Sloc
(N
);
9909 Operand
: constant Node_Id
:= Expression
(N
);
9910 Target_Type
: constant Entity_Id
:= Etype
(N
);
9911 Operand_Type
: Entity_Id
:= Etype
(Operand
);
9913 procedure Handle_Changed_Representation
;
9914 -- This is called in the case of record and array type conversions to
9915 -- see if there is a change of representation to be handled. Change of
9916 -- representation is actually handled at the assignment statement level,
9917 -- and what this procedure does is rewrite node N conversion as an
9918 -- assignment to temporary. If there is no change of representation,
9919 -- then the conversion node is unchanged.
9921 procedure Raise_Accessibility_Error
;
9922 -- Called when we know that an accessibility check will fail. Rewrites
9923 -- node N to an appropriate raise statement and outputs warning msgs.
9924 -- The Etype of the raise node is set to Target_Type.
9926 procedure Real_Range_Check
;
9927 -- Handles generation of range check for real target value
9929 function Has_Extra_Accessibility
(Id
: Entity_Id
) return Boolean;
9930 -- True iff Present (Effective_Extra_Accessibility (Id)) successfully
9931 -- evaluates to True.
9933 -----------------------------------
9934 -- Handle_Changed_Representation --
9935 -----------------------------------
9937 procedure Handle_Changed_Representation
is
9946 -- Nothing else to do if no change of representation
9948 if Same_Representation
(Operand_Type
, Target_Type
) then
9951 -- The real change of representation work is done by the assignment
9952 -- statement processing. So if this type conversion is appearing as
9953 -- the expression of an assignment statement, nothing needs to be
9954 -- done to the conversion.
9956 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
then
9959 -- Otherwise we need to generate a temporary variable, and do the
9960 -- change of representation assignment into that temporary variable.
9961 -- The conversion is then replaced by a reference to this variable.
9966 -- If type is unconstrained we have to add a constraint, copied
9967 -- from the actual value of the left hand side.
9969 if not Is_Constrained
(Target_Type
) then
9970 if Has_Discriminants
(Operand_Type
) then
9971 Disc
:= First_Discriminant
(Operand_Type
);
9973 if Disc
/= First_Stored_Discriminant
(Operand_Type
) then
9974 Disc
:= First_Stored_Discriminant
(Operand_Type
);
9978 while Present
(Disc
) loop
9980 Make_Selected_Component
(Loc
,
9982 Duplicate_Subexpr_Move_Checks
(Operand
),
9984 Make_Identifier
(Loc
, Chars
(Disc
))));
9985 Next_Discriminant
(Disc
);
9988 elsif Is_Array_Type
(Operand_Type
) then
9989 N_Ix
:= First_Index
(Target_Type
);
9992 for J
in 1 .. Number_Dimensions
(Operand_Type
) loop
9994 -- We convert the bounds explicitly. We use an unchecked
9995 -- conversion because bounds checks are done elsewhere.
10000 Unchecked_Convert_To
(Etype
(N_Ix
),
10001 Make_Attribute_Reference
(Loc
,
10003 Duplicate_Subexpr_No_Checks
10004 (Operand
, Name_Req
=> True),
10005 Attribute_Name
=> Name_First
,
10006 Expressions
=> New_List
(
10007 Make_Integer_Literal
(Loc
, J
)))),
10010 Unchecked_Convert_To
(Etype
(N_Ix
),
10011 Make_Attribute_Reference
(Loc
,
10013 Duplicate_Subexpr_No_Checks
10014 (Operand
, Name_Req
=> True),
10015 Attribute_Name
=> Name_Last
,
10016 Expressions
=> New_List
(
10017 Make_Integer_Literal
(Loc
, J
))))));
10024 Odef
:= New_Occurrence_Of
(Target_Type
, Loc
);
10026 if Present
(Cons
) then
10028 Make_Subtype_Indication
(Loc
,
10029 Subtype_Mark
=> Odef
,
10031 Make_Index_Or_Discriminant_Constraint
(Loc
,
10032 Constraints
=> Cons
));
10035 Temp
:= Make_Temporary
(Loc
, 'C');
10037 Make_Object_Declaration
(Loc
,
10038 Defining_Identifier
=> Temp
,
10039 Object_Definition
=> Odef
);
10041 Set_No_Initialization
(Decl
, True);
10043 -- Insert required actions. It is essential to suppress checks
10044 -- since we have suppressed default initialization, which means
10045 -- that the variable we create may have no discriminants.
10050 Make_Assignment_Statement
(Loc
,
10051 Name
=> New_Occurrence_Of
(Temp
, Loc
),
10052 Expression
=> Relocate_Node
(N
))),
10053 Suppress
=> All_Checks
);
10055 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
10058 end Handle_Changed_Representation
;
10060 -------------------------------
10061 -- Raise_Accessibility_Error --
10062 -------------------------------
10064 procedure Raise_Accessibility_Error
is
10066 Error_Msg_Warn
:= SPARK_Mode
/= On
;
10068 Make_Raise_Program_Error
(Sloc
(N
),
10069 Reason
=> PE_Accessibility_Check_Failed
));
10070 Set_Etype
(N
, Target_Type
);
10072 Error_Msg_N
("<<accessibility check failure", N
);
10073 Error_Msg_NE
("\<<& [", N
, Standard_Program_Error
);
10074 end Raise_Accessibility_Error
;
10076 ----------------------
10077 -- Real_Range_Check --
10078 ----------------------
10080 -- Case of conversions to floating-point or fixed-point. If range checks
10081 -- are enabled and the target type has a range constraint, we convert:
10087 -- Tnn : typ'Base := typ'Base (x);
10088 -- [constraint_error when Tnn < typ'First or else Tnn > typ'Last]
10091 -- This is necessary when there is a conversion of integer to float or
10092 -- to fixed-point to ensure that the correct checks are made. It is not
10093 -- necessary for float to float where it is enough to simply set the
10094 -- Do_Range_Check flag.
10096 procedure Real_Range_Check
is
10097 Btyp
: constant Entity_Id
:= Base_Type
(Target_Type
);
10098 Lo
: constant Node_Id
:= Type_Low_Bound
(Target_Type
);
10099 Hi
: constant Node_Id
:= Type_High_Bound
(Target_Type
);
10100 Xtyp
: constant Entity_Id
:= Etype
(Operand
);
10105 -- Nothing to do if conversion was rewritten
10107 if Nkind
(N
) /= N_Type_Conversion
then
10111 -- Nothing to do if range checks suppressed, or target has the same
10112 -- range as the base type (or is the base type).
10114 if Range_Checks_Suppressed
(Target_Type
)
10115 or else (Lo
= Type_Low_Bound
(Btyp
)
10117 Hi
= Type_High_Bound
(Btyp
))
10122 -- Nothing to do if expression is an entity on which checks have been
10125 if Is_Entity_Name
(Operand
)
10126 and then Range_Checks_Suppressed
(Entity
(Operand
))
10131 -- Nothing to do if bounds are all static and we can tell that the
10132 -- expression is within the bounds of the target. Note that if the
10133 -- operand is of an unconstrained floating-point type, then we do
10134 -- not trust it to be in range (might be infinite)
10137 S_Lo
: constant Node_Id
:= Type_Low_Bound
(Xtyp
);
10138 S_Hi
: constant Node_Id
:= Type_High_Bound
(Xtyp
);
10141 if (not Is_Floating_Point_Type
(Xtyp
)
10142 or else Is_Constrained
(Xtyp
))
10143 and then Compile_Time_Known_Value
(S_Lo
)
10144 and then Compile_Time_Known_Value
(S_Hi
)
10145 and then Compile_Time_Known_Value
(Hi
)
10146 and then Compile_Time_Known_Value
(Lo
)
10149 D_Lov
: constant Ureal
:= Expr_Value_R
(Lo
);
10150 D_Hiv
: constant Ureal
:= Expr_Value_R
(Hi
);
10155 if Is_Real_Type
(Xtyp
) then
10156 S_Lov
:= Expr_Value_R
(S_Lo
);
10157 S_Hiv
:= Expr_Value_R
(S_Hi
);
10159 S_Lov
:= UR_From_Uint
(Expr_Value
(S_Lo
));
10160 S_Hiv
:= UR_From_Uint
(Expr_Value
(S_Hi
));
10164 and then S_Lov
>= D_Lov
10165 and then S_Hiv
<= D_Hiv
10167 -- Unset the range check flag on the current value of
10168 -- Expression (N), since the captured Operand may have
10169 -- been rewritten (such as for the case of a conversion
10170 -- to a fixed-point type).
10172 Set_Do_Range_Check
(Expression
(N
), False);
10180 -- For float to float conversions, we are done
10182 if Is_Floating_Point_Type
(Xtyp
)
10184 Is_Floating_Point_Type
(Btyp
)
10189 -- Otherwise rewrite the conversion as described above
10191 Conv
:= Relocate_Node
(N
);
10192 Rewrite
(Subtype_Mark
(Conv
), New_Occurrence_Of
(Btyp
, Loc
));
10193 Set_Etype
(Conv
, Btyp
);
10195 -- Enable overflow except for case of integer to float conversions,
10196 -- where it is never required, since we can never have overflow in
10199 if not Is_Integer_Type
(Etype
(Operand
)) then
10200 Enable_Overflow_Check
(Conv
);
10203 Tnn
:= Make_Temporary
(Loc
, 'T', Conv
);
10205 Insert_Actions
(N
, New_List
(
10206 Make_Object_Declaration
(Loc
,
10207 Defining_Identifier
=> Tnn
,
10208 Object_Definition
=> New_Occurrence_Of
(Btyp
, Loc
),
10209 Constant_Present
=> True,
10210 Expression
=> Conv
),
10212 Make_Raise_Constraint_Error
(Loc
,
10217 Left_Opnd
=> New_Occurrence_Of
(Tnn
, Loc
),
10219 Make_Attribute_Reference
(Loc
,
10220 Attribute_Name
=> Name_First
,
10222 New_Occurrence_Of
(Target_Type
, Loc
))),
10226 Left_Opnd
=> New_Occurrence_Of
(Tnn
, Loc
),
10228 Make_Attribute_Reference
(Loc
,
10229 Attribute_Name
=> Name_Last
,
10231 New_Occurrence_Of
(Target_Type
, Loc
)))),
10232 Reason
=> CE_Range_Check_Failed
)));
10234 Rewrite
(N
, New_Occurrence_Of
(Tnn
, Loc
));
10235 Analyze_And_Resolve
(N
, Btyp
);
10236 end Real_Range_Check
;
10238 -----------------------------
10239 -- Has_Extra_Accessibility --
10240 -----------------------------
10242 -- Returns true for a formal of an anonymous access type or for
10243 -- an Ada 2012-style stand-alone object of an anonymous access type.
10245 function Has_Extra_Accessibility
(Id
: Entity_Id
) return Boolean is
10247 if Is_Formal
(Id
) or else Ekind_In
(Id
, E_Constant
, E_Variable
) then
10248 return Present
(Effective_Extra_Accessibility
(Id
));
10252 end Has_Extra_Accessibility
;
10254 -- Start of processing for Expand_N_Type_Conversion
10257 -- First remove check marks put by the semantic analysis on the type
10258 -- conversion between array types. We need these checks, and they will
10259 -- be generated by this expansion routine, but we do not depend on these
10260 -- flags being set, and since we do intend to expand the checks in the
10261 -- front end, we don't want them on the tree passed to the back end.
10263 if Is_Array_Type
(Target_Type
) then
10264 if Is_Constrained
(Target_Type
) then
10265 Set_Do_Length_Check
(N
, False);
10267 Set_Do_Range_Check
(Operand
, False);
10271 -- Nothing at all to do if conversion is to the identical type so remove
10272 -- the conversion completely, it is useless, except that it may carry
10273 -- an Assignment_OK attribute, which must be propagated to the operand.
10275 if Operand_Type
= Target_Type
then
10276 if Assignment_OK
(N
) then
10277 Set_Assignment_OK
(Operand
);
10280 Rewrite
(N
, Relocate_Node
(Operand
));
10284 -- Nothing to do if this is the second argument of read. This is a
10285 -- "backwards" conversion that will be handled by the specialized code
10286 -- in attribute processing.
10288 if Nkind
(Parent
(N
)) = N_Attribute_Reference
10289 and then Attribute_Name
(Parent
(N
)) = Name_Read
10290 and then Next
(First
(Expressions
(Parent
(N
)))) = N
10295 -- Check for case of converting to a type that has an invariant
10296 -- associated with it. This required an invariant check. We convert
10302 -- do invariant_check (typ (expr)) in typ (expr);
10304 -- using Duplicate_Subexpr to avoid multiple side effects
10306 -- Note: the Comes_From_Source check, and then the resetting of this
10307 -- flag prevents what would otherwise be an infinite recursion.
10309 if Has_Invariants
(Target_Type
)
10310 and then Present
(Invariant_Procedure
(Target_Type
))
10311 and then Comes_From_Source
(N
)
10313 Set_Comes_From_Source
(N
, False);
10315 Make_Expression_With_Actions
(Loc
,
10316 Actions
=> New_List
(
10317 Make_Invariant_Call
(Duplicate_Subexpr
(N
))),
10318 Expression
=> Duplicate_Subexpr_No_Checks
(N
)));
10319 Analyze_And_Resolve
(N
, Target_Type
);
10323 -- Here if we may need to expand conversion
10325 -- If the operand of the type conversion is an arithmetic operation on
10326 -- signed integers, and the based type of the signed integer type in
10327 -- question is smaller than Standard.Integer, we promote both of the
10328 -- operands to type Integer.
10330 -- For example, if we have
10332 -- target-type (opnd1 + opnd2)
10334 -- and opnd1 and opnd2 are of type short integer, then we rewrite
10337 -- target-type (integer(opnd1) + integer(opnd2))
10339 -- We do this because we are always allowed to compute in a larger type
10340 -- if we do the right thing with the result, and in this case we are
10341 -- going to do a conversion which will do an appropriate check to make
10342 -- sure that things are in range of the target type in any case. This
10343 -- avoids some unnecessary intermediate overflows.
10345 -- We might consider a similar transformation in the case where the
10346 -- target is a real type or a 64-bit integer type, and the operand
10347 -- is an arithmetic operation using a 32-bit integer type. However,
10348 -- we do not bother with this case, because it could cause significant
10349 -- inefficiencies on 32-bit machines. On a 64-bit machine it would be
10350 -- much cheaper, but we don't want different behavior on 32-bit and
10351 -- 64-bit machines. Note that the exclusion of the 64-bit case also
10352 -- handles the configurable run-time cases where 64-bit arithmetic
10353 -- may simply be unavailable.
10355 -- Note: this circuit is partially redundant with respect to the circuit
10356 -- in Checks.Apply_Arithmetic_Overflow_Check, but we catch more cases in
10357 -- the processing here. Also we still need the Checks circuit, since we
10358 -- have to be sure not to generate junk overflow checks in the first
10359 -- place, since it would be trick to remove them here.
10361 if Integer_Promotion_Possible
(N
) then
10363 -- All conditions met, go ahead with transformation
10371 Make_Type_Conversion
(Loc
,
10372 Subtype_Mark
=> New_Occurrence_Of
(Standard_Integer
, Loc
),
10373 Expression
=> Relocate_Node
(Right_Opnd
(Operand
)));
10375 Opnd
:= New_Op_Node
(Nkind
(Operand
), Loc
);
10376 Set_Right_Opnd
(Opnd
, R
);
10378 if Nkind
(Operand
) in N_Binary_Op
then
10380 Make_Type_Conversion
(Loc
,
10381 Subtype_Mark
=> New_Occurrence_Of
(Standard_Integer
, Loc
),
10382 Expression
=> Relocate_Node
(Left_Opnd
(Operand
)));
10384 Set_Left_Opnd
(Opnd
, L
);
10388 Make_Type_Conversion
(Loc
,
10389 Subtype_Mark
=> Relocate_Node
(Subtype_Mark
(N
)),
10390 Expression
=> Opnd
));
10392 Analyze_And_Resolve
(N
, Target_Type
);
10397 -- Do validity check if validity checking operands
10399 if Validity_Checks_On
and Validity_Check_Operands
then
10400 Ensure_Valid
(Operand
);
10403 -- Special case of converting from non-standard boolean type
10405 if Is_Boolean_Type
(Operand_Type
)
10406 and then (Nonzero_Is_True
(Operand_Type
))
10408 Adjust_Condition
(Operand
);
10409 Set_Etype
(Operand
, Standard_Boolean
);
10410 Operand_Type
:= Standard_Boolean
;
10413 -- Case of converting to an access type
10415 if Is_Access_Type
(Target_Type
) then
10417 -- Apply an accessibility check when the conversion operand is an
10418 -- access parameter (or a renaming thereof), unless conversion was
10419 -- expanded from an Unchecked_ or Unrestricted_Access attribute.
10420 -- Note that other checks may still need to be applied below (such
10421 -- as tagged type checks).
10423 if Is_Entity_Name
(Operand
)
10424 and then Has_Extra_Accessibility
(Entity
(Operand
))
10425 and then Ekind
(Etype
(Operand
)) = E_Anonymous_Access_Type
10426 and then (Nkind
(Original_Node
(N
)) /= N_Attribute_Reference
10427 or else Attribute_Name
(Original_Node
(N
)) = Name_Access
)
10429 Apply_Accessibility_Check
10430 (Operand
, Target_Type
, Insert_Node
=> Operand
);
10432 -- If the level of the operand type is statically deeper than the
10433 -- level of the target type, then force Program_Error. Note that this
10434 -- can only occur for cases where the attribute is within the body of
10435 -- an instantiation, otherwise the conversion will already have been
10436 -- rejected as illegal.
10438 -- Note: warnings are issued by the analyzer for the instance cases
10440 elsif In_Instance_Body
10442 -- The case where the target type is an anonymous access type of
10443 -- a discriminant is excluded, because the level of such a type
10444 -- depends on the context and currently the level returned for such
10445 -- types is zero, resulting in warnings about about check failures
10446 -- in certain legal cases involving class-wide interfaces as the
10447 -- designated type (some cases, such as return statements, are
10448 -- checked at run time, but not clear if these are handled right
10449 -- in general, see 3.10.2(12/2-12.5/3) ???).
10452 not (Ekind
(Target_Type
) = E_Anonymous_Access_Type
10453 and then Present
(Associated_Node_For_Itype
(Target_Type
))
10454 and then Nkind
(Associated_Node_For_Itype
(Target_Type
)) =
10455 N_Discriminant_Specification
)
10457 Type_Access_Level
(Operand_Type
) > Type_Access_Level
(Target_Type
)
10459 Raise_Accessibility_Error
;
10461 -- When the operand is a selected access discriminant the check needs
10462 -- to be made against the level of the object denoted by the prefix
10463 -- of the selected name. Force Program_Error for this case as well
10464 -- (this accessibility violation can only happen if within the body
10465 -- of an instantiation).
10467 elsif In_Instance_Body
10468 and then Ekind
(Operand_Type
) = E_Anonymous_Access_Type
10469 and then Nkind
(Operand
) = N_Selected_Component
10470 and then Object_Access_Level
(Operand
) >
10471 Type_Access_Level
(Target_Type
)
10473 Raise_Accessibility_Error
;
10478 -- Case of conversions of tagged types and access to tagged types
10480 -- When needed, that is to say when the expression is class-wide, Add
10481 -- runtime a tag check for (strict) downward conversion by using the
10482 -- membership test, generating:
10484 -- [constraint_error when Operand not in Target_Type'Class]
10486 -- or in the access type case
10488 -- [constraint_error
10489 -- when Operand /= null
10490 -- and then Operand.all not in
10491 -- Designated_Type (Target_Type)'Class]
10493 if (Is_Access_Type
(Target_Type
)
10494 and then Is_Tagged_Type
(Designated_Type
(Target_Type
)))
10495 or else Is_Tagged_Type
(Target_Type
)
10497 -- Do not do any expansion in the access type case if the parent is a
10498 -- renaming, since this is an error situation which will be caught by
10499 -- Sem_Ch8, and the expansion can interfere with this error check.
10501 if Is_Access_Type
(Target_Type
) and then Is_Renamed_Object
(N
) then
10505 -- Otherwise, proceed with processing tagged conversion
10507 Tagged_Conversion
: declare
10508 Actual_Op_Typ
: Entity_Id
;
10509 Actual_Targ_Typ
: Entity_Id
;
10510 Make_Conversion
: Boolean := False;
10511 Root_Op_Typ
: Entity_Id
;
10513 procedure Make_Tag_Check
(Targ_Typ
: Entity_Id
);
10514 -- Create a membership check to test whether Operand is a member
10515 -- of Targ_Typ. If the original Target_Type is an access, include
10516 -- a test for null value. The check is inserted at N.
10518 --------------------
10519 -- Make_Tag_Check --
10520 --------------------
10522 procedure Make_Tag_Check
(Targ_Typ
: Entity_Id
) is
10527 -- [Constraint_Error
10528 -- when Operand /= null
10529 -- and then Operand.all not in Targ_Typ]
10531 if Is_Access_Type
(Target_Type
) then
10533 Make_And_Then
(Loc
,
10536 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Operand
),
10537 Right_Opnd
=> Make_Null
(Loc
)),
10542 Make_Explicit_Dereference
(Loc
,
10543 Prefix
=> Duplicate_Subexpr_No_Checks
(Operand
)),
10544 Right_Opnd
=> New_Occurrence_Of
(Targ_Typ
, Loc
)));
10547 -- [Constraint_Error when Operand not in Targ_Typ]
10552 Left_Opnd
=> Duplicate_Subexpr_No_Checks
(Operand
),
10553 Right_Opnd
=> New_Occurrence_Of
(Targ_Typ
, Loc
));
10557 Make_Raise_Constraint_Error
(Loc
,
10559 Reason
=> CE_Tag_Check_Failed
));
10560 end Make_Tag_Check
;
10562 -- Start of processing for Tagged_Conversion
10565 -- Handle entities from the limited view
10567 if Is_Access_Type
(Operand_Type
) then
10569 Available_View
(Designated_Type
(Operand_Type
));
10571 Actual_Op_Typ
:= Operand_Type
;
10574 if Is_Access_Type
(Target_Type
) then
10576 Available_View
(Designated_Type
(Target_Type
));
10578 Actual_Targ_Typ
:= Target_Type
;
10581 Root_Op_Typ
:= Root_Type
(Actual_Op_Typ
);
10583 -- Ada 2005 (AI-251): Handle interface type conversion
10585 if Is_Interface
(Actual_Op_Typ
) then
10586 Expand_Interface_Conversion
(N
);
10590 if not Tag_Checks_Suppressed
(Actual_Targ_Typ
) then
10592 -- Create a runtime tag check for a downward class-wide type
10595 if Is_Class_Wide_Type
(Actual_Op_Typ
)
10596 and then Actual_Op_Typ
/= Actual_Targ_Typ
10597 and then Root_Op_Typ
/= Actual_Targ_Typ
10598 and then Is_Ancestor
(Root_Op_Typ
, Actual_Targ_Typ
,
10599 Use_Full_View
=> True)
10601 Make_Tag_Check
(Class_Wide_Type
(Actual_Targ_Typ
));
10602 Make_Conversion
:= True;
10605 -- AI05-0073: If the result subtype of the function is defined
10606 -- by an access_definition designating a specific tagged type
10607 -- T, a check is made that the result value is null or the tag
10608 -- of the object designated by the result value identifies T.
10609 -- Constraint_Error is raised if this check fails.
10611 if Nkind
(Parent
(N
)) = N_Simple_Return_Statement
then
10614 Func_Typ
: Entity_Id
;
10617 -- Climb scope stack looking for the enclosing function
10619 Func
:= Current_Scope
;
10620 while Present
(Func
)
10621 and then Ekind
(Func
) /= E_Function
10623 Func
:= Scope
(Func
);
10626 -- The function's return subtype must be defined using
10627 -- an access definition.
10629 if Nkind
(Result_Definition
(Parent
(Func
))) =
10630 N_Access_Definition
10632 Func_Typ
:= Directly_Designated_Type
(Etype
(Func
));
10634 -- The return subtype denotes a specific tagged type,
10635 -- in other words, a non class-wide type.
10637 if Is_Tagged_Type
(Func_Typ
)
10638 and then not Is_Class_Wide_Type
(Func_Typ
)
10640 Make_Tag_Check
(Actual_Targ_Typ
);
10641 Make_Conversion
:= True;
10647 -- We have generated a tag check for either a class-wide type
10648 -- conversion or for AI05-0073.
10650 if Make_Conversion
then
10655 Make_Unchecked_Type_Conversion
(Loc
,
10656 Subtype_Mark
=> New_Occurrence_Of
(Target_Type
, Loc
),
10657 Expression
=> Relocate_Node
(Expression
(N
)));
10659 Analyze_And_Resolve
(N
, Target_Type
);
10663 end Tagged_Conversion
;
10665 -- Case of other access type conversions
10667 elsif Is_Access_Type
(Target_Type
) then
10668 Apply_Constraint_Check
(Operand
, Target_Type
);
10670 -- Case of conversions from a fixed-point type
10672 -- These conversions require special expansion and processing, found in
10673 -- the Exp_Fixd package. We ignore cases where Conversion_OK is set,
10674 -- since from a semantic point of view, these are simple integer
10675 -- conversions, which do not need further processing.
10677 elsif Is_Fixed_Point_Type
(Operand_Type
)
10678 and then not Conversion_OK
(N
)
10680 -- We should never see universal fixed at this case, since the
10681 -- expansion of the constituent divide or multiply should have
10682 -- eliminated the explicit mention of universal fixed.
10684 pragma Assert
(Operand_Type
/= Universal_Fixed
);
10686 -- Check for special case of the conversion to universal real that
10687 -- occurs as a result of the use of a round attribute. In this case,
10688 -- the real type for the conversion is taken from the target type of
10689 -- the Round attribute and the result must be marked as rounded.
10691 if Target_Type
= Universal_Real
10692 and then Nkind
(Parent
(N
)) = N_Attribute_Reference
10693 and then Attribute_Name
(Parent
(N
)) = Name_Round
10695 Set_Rounded_Result
(N
);
10696 Set_Etype
(N
, Etype
(Parent
(N
)));
10699 -- Otherwise do correct fixed-conversion, but skip these if the
10700 -- Conversion_OK flag is set, because from a semantic point of view
10701 -- these are simple integer conversions needing no further processing
10702 -- (the backend will simply treat them as integers).
10704 if not Conversion_OK
(N
) then
10705 if Is_Fixed_Point_Type
(Etype
(N
)) then
10706 Expand_Convert_Fixed_To_Fixed
(N
);
10709 elsif Is_Integer_Type
(Etype
(N
)) then
10710 Expand_Convert_Fixed_To_Integer
(N
);
10713 pragma Assert
(Is_Floating_Point_Type
(Etype
(N
)));
10714 Expand_Convert_Fixed_To_Float
(N
);
10719 -- Case of conversions to a fixed-point type
10721 -- These conversions require special expansion and processing, found in
10722 -- the Exp_Fixd package. Again, ignore cases where Conversion_OK is set,
10723 -- since from a semantic point of view, these are simple integer
10724 -- conversions, which do not need further processing.
10726 elsif Is_Fixed_Point_Type
(Target_Type
)
10727 and then not Conversion_OK
(N
)
10729 if Is_Integer_Type
(Operand_Type
) then
10730 Expand_Convert_Integer_To_Fixed
(N
);
10733 pragma Assert
(Is_Floating_Point_Type
(Operand_Type
));
10734 Expand_Convert_Float_To_Fixed
(N
);
10738 -- Case of float-to-integer conversions
10740 -- We also handle float-to-fixed conversions with Conversion_OK set
10741 -- since semantically the fixed-point target is treated as though it
10742 -- were an integer in such cases.
10744 elsif Is_Floating_Point_Type
(Operand_Type
)
10746 (Is_Integer_Type
(Target_Type
)
10748 (Is_Fixed_Point_Type
(Target_Type
) and then Conversion_OK
(N
)))
10750 -- One more check here, gcc is still not able to do conversions of
10751 -- this type with proper overflow checking, and so gigi is doing an
10752 -- approximation of what is required by doing floating-point compares
10753 -- with the end-point. But that can lose precision in some cases, and
10754 -- give a wrong result. Converting the operand to Universal_Real is
10755 -- helpful, but still does not catch all cases with 64-bit integers
10756 -- on targets with only 64-bit floats.
10758 -- The above comment seems obsoleted by Apply_Float_Conversion_Check
10759 -- Can this code be removed ???
10761 if Do_Range_Check
(Operand
) then
10763 Make_Type_Conversion
(Loc
,
10765 New_Occurrence_Of
(Universal_Real
, Loc
),
10767 Relocate_Node
(Operand
)));
10769 Set_Etype
(Operand
, Universal_Real
);
10770 Enable_Range_Check
(Operand
);
10771 Set_Do_Range_Check
(Expression
(Operand
), False);
10774 -- Case of array conversions
10776 -- Expansion of array conversions, add required length/range checks but
10777 -- only do this if there is no change of representation. For handling of
10778 -- this case, see Handle_Changed_Representation.
10780 elsif Is_Array_Type
(Target_Type
) then
10781 if Is_Constrained
(Target_Type
) then
10782 Apply_Length_Check
(Operand
, Target_Type
);
10784 Apply_Range_Check
(Operand
, Target_Type
);
10787 Handle_Changed_Representation
;
10789 -- Case of conversions of discriminated types
10791 -- Add required discriminant checks if target is constrained. Again this
10792 -- change is skipped if we have a change of representation.
10794 elsif Has_Discriminants
(Target_Type
)
10795 and then Is_Constrained
(Target_Type
)
10797 Apply_Discriminant_Check
(Operand
, Target_Type
);
10798 Handle_Changed_Representation
;
10800 -- Case of all other record conversions. The only processing required
10801 -- is to check for a change of representation requiring the special
10802 -- assignment processing.
10804 elsif Is_Record_Type
(Target_Type
) then
10806 -- Ada 2005 (AI-216): Program_Error is raised when converting from
10807 -- a derived Unchecked_Union type to an unconstrained type that is
10808 -- not Unchecked_Union if the operand lacks inferable discriminants.
10810 if Is_Derived_Type
(Operand_Type
)
10811 and then Is_Unchecked_Union
(Base_Type
(Operand_Type
))
10812 and then not Is_Constrained
(Target_Type
)
10813 and then not Is_Unchecked_Union
(Base_Type
(Target_Type
))
10814 and then not Has_Inferable_Discriminants
(Operand
)
10816 -- To prevent Gigi from generating illegal code, we generate a
10817 -- Program_Error node, but we give it the target type of the
10818 -- conversion (is this requirement documented somewhere ???)
10821 PE
: constant Node_Id
:= Make_Raise_Program_Error
(Loc
,
10822 Reason
=> PE_Unchecked_Union_Restriction
);
10825 Set_Etype
(PE
, Target_Type
);
10830 Handle_Changed_Representation
;
10833 -- Case of conversions of enumeration types
10835 elsif Is_Enumeration_Type
(Target_Type
) then
10837 -- Special processing is required if there is a change of
10838 -- representation (from enumeration representation clauses).
10840 if not Same_Representation
(Target_Type
, Operand_Type
) then
10842 -- Convert: x(y) to x'val (ytyp'val (y))
10845 Make_Attribute_Reference
(Loc
,
10846 Prefix
=> New_Occurrence_Of
(Target_Type
, Loc
),
10847 Attribute_Name
=> Name_Val
,
10848 Expressions
=> New_List
(
10849 Make_Attribute_Reference
(Loc
,
10850 Prefix
=> New_Occurrence_Of
(Operand_Type
, Loc
),
10851 Attribute_Name
=> Name_Pos
,
10852 Expressions
=> New_List
(Operand
)))));
10854 Analyze_And_Resolve
(N
, Target_Type
);
10857 -- Case of conversions to floating-point
10859 elsif Is_Floating_Point_Type
(Target_Type
) then
10863 -- At this stage, either the conversion node has been transformed into
10864 -- some other equivalent expression, or left as a conversion that can be
10865 -- handled by Gigi, in the following cases:
10867 -- Conversions with no change of representation or type
10869 -- Numeric conversions involving integer, floating- and fixed-point
10870 -- values. Fixed-point values are allowed only if Conversion_OK is
10871 -- set, i.e. if the fixed-point values are to be treated as integers.
10873 -- No other conversions should be passed to Gigi
10875 -- Check: are these rules stated in sinfo??? if so, why restate here???
10877 -- The only remaining step is to generate a range check if we still have
10878 -- a type conversion at this stage and Do_Range_Check is set. For now we
10879 -- do this only for conversions of discrete types and for float-to-float
10882 if Nkind
(N
) = N_Type_Conversion
then
10884 -- For now we only support floating-point cases where both source
10885 -- and target are floating-point types. Conversions where the source
10886 -- and target involve integer or fixed-point types are still TBD,
10887 -- though not clear whether those can even happen at this point, due
10888 -- to transformations above. ???
10890 if Is_Floating_Point_Type
(Etype
(N
))
10891 and then Is_Floating_Point_Type
(Etype
(Expression
(N
)))
10893 if Do_Range_Check
(Expression
(N
))
10894 and then Is_Floating_Point_Type
(Target_Type
)
10896 Generate_Range_Check
10897 (Expression
(N
), Target_Type
, CE_Range_Check_Failed
);
10900 -- Discrete-to-discrete conversions
10902 elsif Is_Discrete_Type
(Etype
(N
)) then
10904 Expr
: constant Node_Id
:= Expression
(N
);
10909 if Do_Range_Check
(Expr
)
10910 and then Is_Discrete_Type
(Etype
(Expr
))
10912 Set_Do_Range_Check
(Expr
, False);
10914 -- Before we do a range check, we have to deal with treating
10915 -- a fixed-point operand as an integer. The way we do this
10916 -- is simply to do an unchecked conversion to an appropriate
10917 -- integer type large enough to hold the result.
10919 -- This code is not active yet, because we are only dealing
10920 -- with discrete types so far ???
10922 if Nkind
(Expr
) in N_Has_Treat_Fixed_As_Integer
10923 and then Treat_Fixed_As_Integer
(Expr
)
10925 Ftyp
:= Base_Type
(Etype
(Expr
));
10927 if Esize
(Ftyp
) >= Esize
(Standard_Integer
) then
10928 Ityp
:= Standard_Long_Long_Integer
;
10930 Ityp
:= Standard_Integer
;
10933 Rewrite
(Expr
, Unchecked_Convert_To
(Ityp
, Expr
));
10936 -- Reset overflow flag, since the range check will include
10937 -- dealing with possible overflow, and generate the check.
10938 -- If Address is either a source type or target type,
10939 -- suppress range check to avoid typing anomalies when
10940 -- it is a visible integer type.
10942 Set_Do_Overflow_Check
(N
, False);
10944 if not Is_Descendent_Of_Address
(Etype
(Expr
))
10945 and then not Is_Descendent_Of_Address
(Target_Type
)
10947 Generate_Range_Check
10948 (Expr
, Target_Type
, CE_Range_Check_Failed
);
10955 -- Here at end of processing
10958 -- Apply predicate check if required. Note that we can't just call
10959 -- Apply_Predicate_Check here, because the type looks right after
10960 -- the conversion and it would omit the check. The Comes_From_Source
10961 -- guard is necessary to prevent infinite recursions when we generate
10962 -- internal conversions for the purpose of checking predicates.
10964 if Present
(Predicate_Function
(Target_Type
))
10965 and then Target_Type
/= Operand_Type
10966 and then Comes_From_Source
(N
)
10969 New_Expr
: constant Node_Id
:= Duplicate_Subexpr
(N
);
10972 -- Avoid infinite recursion on the subsequent expansion of
10973 -- of the copy of the original type conversion.
10975 Set_Comes_From_Source
(New_Expr
, False);
10976 Insert_Action
(N
, Make_Predicate_Check
(Target_Type
, New_Expr
));
10979 end Expand_N_Type_Conversion
;
10981 -----------------------------------
10982 -- Expand_N_Unchecked_Expression --
10983 -----------------------------------
10985 -- Remove the unchecked expression node from the tree. Its job was simply
10986 -- to make sure that its constituent expression was handled with checks
10987 -- off, and now that that is done, we can remove it from the tree, and
10988 -- indeed must, since Gigi does not expect to see these nodes.
10990 procedure Expand_N_Unchecked_Expression
(N
: Node_Id
) is
10991 Exp
: constant Node_Id
:= Expression
(N
);
10993 Set_Assignment_OK
(Exp
, Assignment_OK
(N
) or else Assignment_OK
(Exp
));
10995 end Expand_N_Unchecked_Expression
;
10997 ----------------------------------------
10998 -- Expand_N_Unchecked_Type_Conversion --
10999 ----------------------------------------
11001 -- If this cannot be handled by Gigi and we haven't already made a
11002 -- temporary for it, do it now.
11004 procedure Expand_N_Unchecked_Type_Conversion
(N
: Node_Id
) is
11005 Target_Type
: constant Entity_Id
:= Etype
(N
);
11006 Operand
: constant Node_Id
:= Expression
(N
);
11007 Operand_Type
: constant Entity_Id
:= Etype
(Operand
);
11010 -- Nothing at all to do if conversion is to the identical type so remove
11011 -- the conversion completely, it is useless, except that it may carry
11012 -- an Assignment_OK indication which must be propagated to the operand.
11014 if Operand_Type
= Target_Type
then
11016 -- Code duplicates Expand_N_Unchecked_Expression above, factor???
11018 if Assignment_OK
(N
) then
11019 Set_Assignment_OK
(Operand
);
11022 Rewrite
(N
, Relocate_Node
(Operand
));
11026 -- If we have a conversion of a compile time known value to a target
11027 -- type and the value is in range of the target type, then we can simply
11028 -- replace the construct by an integer literal of the correct type. We
11029 -- only apply this to integer types being converted. Possibly it may
11030 -- apply in other cases, but it is too much trouble to worry about.
11032 -- Note that we do not do this transformation if the Kill_Range_Check
11033 -- flag is set, since then the value may be outside the expected range.
11034 -- This happens in the Normalize_Scalars case.
11036 -- We also skip this if either the target or operand type is biased
11037 -- because in this case, the unchecked conversion is supposed to
11038 -- preserve the bit pattern, not the integer value.
11040 if Is_Integer_Type
(Target_Type
)
11041 and then not Has_Biased_Representation
(Target_Type
)
11042 and then Is_Integer_Type
(Operand_Type
)
11043 and then not Has_Biased_Representation
(Operand_Type
)
11044 and then Compile_Time_Known_Value
(Operand
)
11045 and then not Kill_Range_Check
(N
)
11048 Val
: constant Uint
:= Expr_Value
(Operand
);
11051 if Compile_Time_Known_Value
(Type_Low_Bound
(Target_Type
))
11053 Compile_Time_Known_Value
(Type_High_Bound
(Target_Type
))
11055 Val
>= Expr_Value
(Type_Low_Bound
(Target_Type
))
11057 Val
<= Expr_Value
(Type_High_Bound
(Target_Type
))
11059 Rewrite
(N
, Make_Integer_Literal
(Sloc
(N
), Val
));
11061 -- If Address is the target type, just set the type to avoid a
11062 -- spurious type error on the literal when Address is a visible
11065 if Is_Descendent_Of_Address
(Target_Type
) then
11066 Set_Etype
(N
, Target_Type
);
11068 Analyze_And_Resolve
(N
, Target_Type
);
11076 -- Nothing to do if conversion is safe
11078 if Safe_Unchecked_Type_Conversion
(N
) then
11082 -- Otherwise force evaluation unless Assignment_OK flag is set (this
11083 -- flag indicates ??? More comments needed here)
11085 if Assignment_OK
(N
) then
11088 Force_Evaluation
(N
);
11090 end Expand_N_Unchecked_Type_Conversion
;
11092 ----------------------------
11093 -- Expand_Record_Equality --
11094 ----------------------------
11096 -- For non-variant records, Equality is expanded when needed into:
11098 -- and then Lhs.Discr1 = Rhs.Discr1
11100 -- and then Lhs.Discrn = Rhs.Discrn
11101 -- and then Lhs.Cmp1 = Rhs.Cmp1
11103 -- and then Lhs.Cmpn = Rhs.Cmpn
11105 -- The expression is folded by the back-end for adjacent fields. This
11106 -- function is called for tagged record in only one occasion: for imple-
11107 -- menting predefined primitive equality (see Predefined_Primitives_Bodies)
11108 -- otherwise the primitive "=" is used directly.
11110 function Expand_Record_Equality
11115 Bodies
: List_Id
) return Node_Id
11117 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
11122 First_Time
: Boolean := True;
11124 function Element_To_Compare
(C
: Entity_Id
) return Entity_Id
;
11125 -- Return the next discriminant or component to compare, starting with
11126 -- C, skipping inherited components.
11128 ------------------------
11129 -- Element_To_Compare --
11130 ------------------------
11132 function Element_To_Compare
(C
: Entity_Id
) return Entity_Id
is
11138 -- Exit loop when the next element to be compared is found, or
11139 -- there is no more such element.
11141 exit when No
(Comp
);
11143 exit when Ekind_In
(Comp
, E_Discriminant
, E_Component
)
11146 -- Skip inherited components
11148 -- Note: for a tagged type, we always generate the "=" primitive
11149 -- for the base type (not on the first subtype), so the test for
11150 -- Comp /= Original_Record_Component (Comp) is True for
11151 -- inherited components only.
11153 (Is_Tagged_Type
(Typ
)
11154 and then Comp
/= Original_Record_Component
(Comp
))
11158 or else Chars
(Comp
) = Name_uTag
11160 -- The .NET/JVM version of type Root_Controlled contains two
11161 -- fields which should not be considered part of the object. To
11162 -- achieve proper equiality between two controlled objects on
11163 -- .NET/JVM, skip _Parent whenever it has type Root_Controlled.
11165 or else (Chars
(Comp
) = Name_uParent
11166 and then VM_Target
/= No_VM
11167 and then Etype
(Comp
) = RTE
(RE_Root_Controlled
))
11169 -- Skip interface elements (secondary tags???)
11171 or else Is_Interface
(Etype
(Comp
)));
11173 Next_Entity
(Comp
);
11177 end Element_To_Compare
;
11179 -- Start of processing for Expand_Record_Equality
11182 -- Generates the following code: (assuming that Typ has one Discr and
11183 -- component C2 is also a record)
11186 -- and then Lhs.Discr1 = Rhs.Discr1
11187 -- and then Lhs.C1 = Rhs.C1
11188 -- and then Lhs.C2.C1=Rhs.C2.C1 and then ... Lhs.C2.Cn=Rhs.C2.Cn
11190 -- and then Lhs.Cmpn = Rhs.Cmpn
11192 Result
:= New_Occurrence_Of
(Standard_True
, Loc
);
11193 C
:= Element_To_Compare
(First_Entity
(Typ
));
11194 while Present
(C
) loop
11202 First_Time
:= False;
11206 New_Lhs
:= New_Copy_Tree
(Lhs
);
11207 New_Rhs
:= New_Copy_Tree
(Rhs
);
11211 Expand_Composite_Equality
(Nod
, Etype
(C
),
11213 Make_Selected_Component
(Loc
,
11215 Selector_Name
=> New_Occurrence_Of
(C
, Loc
)),
11217 Make_Selected_Component
(Loc
,
11219 Selector_Name
=> New_Occurrence_Of
(C
, Loc
)),
11222 -- If some (sub)component is an unchecked_union, the whole
11223 -- operation will raise program error.
11225 if Nkind
(Check
) = N_Raise_Program_Error
then
11227 Set_Etype
(Result
, Standard_Boolean
);
11231 Make_And_Then
(Loc
,
11232 Left_Opnd
=> Result
,
11233 Right_Opnd
=> Check
);
11237 C
:= Element_To_Compare
(Next_Entity
(C
));
11241 end Expand_Record_Equality
;
11243 ---------------------------
11244 -- Expand_Set_Membership --
11245 ---------------------------
11247 procedure Expand_Set_Membership
(N
: Node_Id
) is
11248 Lop
: constant Node_Id
:= Left_Opnd
(N
);
11252 function Make_Cond
(Alt
: Node_Id
) return Node_Id
;
11253 -- If the alternative is a subtype mark, create a simple membership
11254 -- test. Otherwise create an equality test for it.
11260 function Make_Cond
(Alt
: Node_Id
) return Node_Id
is
11262 L
: constant Node_Id
:= New_Copy
(Lop
);
11263 R
: constant Node_Id
:= Relocate_Node
(Alt
);
11266 if (Is_Entity_Name
(Alt
) and then Is_Type
(Entity
(Alt
)))
11267 or else Nkind
(Alt
) = N_Range
11270 Make_In
(Sloc
(Alt
),
11275 Make_Op_Eq
(Sloc
(Alt
),
11283 -- Start of processing for Expand_Set_Membership
11286 Remove_Side_Effects
(Lop
);
11288 Alt
:= Last
(Alternatives
(N
));
11289 Res
:= Make_Cond
(Alt
);
11292 while Present
(Alt
) loop
11294 Make_Or_Else
(Sloc
(Alt
),
11295 Left_Opnd
=> Make_Cond
(Alt
),
11296 Right_Opnd
=> Res
);
11301 Analyze_And_Resolve
(N
, Standard_Boolean
);
11302 end Expand_Set_Membership
;
11304 -----------------------------------
11305 -- Expand_Short_Circuit_Operator --
11306 -----------------------------------
11308 -- Deal with special expansion if actions are present for the right operand
11309 -- and deal with optimizing case of arguments being True or False. We also
11310 -- deal with the special case of non-standard boolean values.
11312 procedure Expand_Short_Circuit_Operator
(N
: Node_Id
) is
11313 Loc
: constant Source_Ptr
:= Sloc
(N
);
11314 Typ
: constant Entity_Id
:= Etype
(N
);
11315 Left
: constant Node_Id
:= Left_Opnd
(N
);
11316 Right
: constant Node_Id
:= Right_Opnd
(N
);
11317 LocR
: constant Source_Ptr
:= Sloc
(Right
);
11320 Shortcut_Value
: constant Boolean := Nkind
(N
) = N_Or_Else
;
11321 Shortcut_Ent
: constant Entity_Id
:= Boolean_Literals
(Shortcut_Value
);
11322 -- If Left = Shortcut_Value then Right need not be evaluated
11325 -- Deal with non-standard booleans
11327 if Is_Boolean_Type
(Typ
) then
11328 Adjust_Condition
(Left
);
11329 Adjust_Condition
(Right
);
11330 Set_Etype
(N
, Standard_Boolean
);
11333 -- Check for cases where left argument is known to be True or False
11335 if Compile_Time_Known_Value
(Left
) then
11337 -- Mark SCO for left condition as compile time known
11339 if Generate_SCO
and then Comes_From_Source
(Left
) then
11340 Set_SCO_Condition
(Left
, Expr_Value_E
(Left
) = Standard_True
);
11343 -- Rewrite True AND THEN Right / False OR ELSE Right to Right.
11344 -- Any actions associated with Right will be executed unconditionally
11345 -- and can thus be inserted into the tree unconditionally.
11347 if Expr_Value_E
(Left
) /= Shortcut_Ent
then
11348 if Present
(Actions
(N
)) then
11349 Insert_Actions
(N
, Actions
(N
));
11352 Rewrite
(N
, Right
);
11354 -- Rewrite False AND THEN Right / True OR ELSE Right to Left.
11355 -- In this case we can forget the actions associated with Right,
11356 -- since they will never be executed.
11359 Kill_Dead_Code
(Right
);
11360 Kill_Dead_Code
(Actions
(N
));
11361 Rewrite
(N
, New_Occurrence_Of
(Shortcut_Ent
, Loc
));
11364 Adjust_Result_Type
(N
, Typ
);
11368 -- If Actions are present for the right operand, we have to do some
11369 -- special processing. We can't just let these actions filter back into
11370 -- code preceding the short circuit (which is what would have happened
11371 -- if we had not trapped them in the short-circuit form), since they
11372 -- must only be executed if the right operand of the short circuit is
11373 -- executed and not otherwise.
11375 if Present
(Actions
(N
)) then
11376 Actlist
:= Actions
(N
);
11378 -- We now use an Expression_With_Actions node for the right operand
11379 -- of the short-circuit form. Note that this solves the traceability
11380 -- problems for coverage analysis.
11383 Make_Expression_With_Actions
(LocR
,
11384 Expression
=> Relocate_Node
(Right
),
11385 Actions
=> Actlist
));
11386 Set_Actions
(N
, No_List
);
11387 Analyze_And_Resolve
(Right
, Standard_Boolean
);
11389 Adjust_Result_Type
(N
, Typ
);
11393 -- No actions present, check for cases of right argument True/False
11395 if Compile_Time_Known_Value
(Right
) then
11397 -- Mark SCO for left condition as compile time known
11399 if Generate_SCO
and then Comes_From_Source
(Right
) then
11400 Set_SCO_Condition
(Right
, Expr_Value_E
(Right
) = Standard_True
);
11403 -- Change (Left and then True), (Left or else False) to Left.
11404 -- Note that we know there are no actions associated with the right
11405 -- operand, since we just checked for this case above.
11407 if Expr_Value_E
(Right
) /= Shortcut_Ent
then
11410 -- Change (Left and then False), (Left or else True) to Right,
11411 -- making sure to preserve any side effects associated with the Left
11415 Remove_Side_Effects
(Left
);
11416 Rewrite
(N
, New_Occurrence_Of
(Shortcut_Ent
, Loc
));
11420 Adjust_Result_Type
(N
, Typ
);
11421 end Expand_Short_Circuit_Operator
;
11423 -------------------------------------
11424 -- Fixup_Universal_Fixed_Operation --
11425 -------------------------------------
11427 procedure Fixup_Universal_Fixed_Operation
(N
: Node_Id
) is
11428 Conv
: constant Node_Id
:= Parent
(N
);
11431 -- We must have a type conversion immediately above us
11433 pragma Assert
(Nkind
(Conv
) = N_Type_Conversion
);
11435 -- Normally the type conversion gives our target type. The exception
11436 -- occurs in the case of the Round attribute, where the conversion
11437 -- will be to universal real, and our real type comes from the Round
11438 -- attribute (as well as an indication that we must round the result)
11440 if Nkind
(Parent
(Conv
)) = N_Attribute_Reference
11441 and then Attribute_Name
(Parent
(Conv
)) = Name_Round
11443 Set_Etype
(N
, Etype
(Parent
(Conv
)));
11444 Set_Rounded_Result
(N
);
11446 -- Normal case where type comes from conversion above us
11449 Set_Etype
(N
, Etype
(Conv
));
11451 end Fixup_Universal_Fixed_Operation
;
11453 ---------------------------------
11454 -- Has_Inferable_Discriminants --
11455 ---------------------------------
11457 function Has_Inferable_Discriminants
(N
: Node_Id
) return Boolean is
11459 function Prefix_Is_Formal_Parameter
(N
: Node_Id
) return Boolean;
11460 -- Determines whether the left-most prefix of a selected component is a
11461 -- formal parameter in a subprogram. Assumes N is a selected component.
11463 --------------------------------
11464 -- Prefix_Is_Formal_Parameter --
11465 --------------------------------
11467 function Prefix_Is_Formal_Parameter
(N
: Node_Id
) return Boolean is
11468 Sel_Comp
: Node_Id
;
11471 -- Move to the left-most prefix by climbing up the tree
11474 while Present
(Parent
(Sel_Comp
))
11475 and then Nkind
(Parent
(Sel_Comp
)) = N_Selected_Component
11477 Sel_Comp
:= Parent
(Sel_Comp
);
11480 return Ekind
(Entity
(Prefix
(Sel_Comp
))) in Formal_Kind
;
11481 end Prefix_Is_Formal_Parameter
;
11483 -- Start of processing for Has_Inferable_Discriminants
11486 -- For selected components, the subtype of the selector must be a
11487 -- constrained Unchecked_Union. If the component is subject to a
11488 -- per-object constraint, then the enclosing object must have inferable
11491 if Nkind
(N
) = N_Selected_Component
then
11492 if Has_Per_Object_Constraint
(Entity
(Selector_Name
(N
))) then
11494 -- A small hack. If we have a per-object constrained selected
11495 -- component of a formal parameter, return True since we do not
11496 -- know the actual parameter association yet.
11498 if Prefix_Is_Formal_Parameter
(N
) then
11501 -- Otherwise, check the enclosing object and the selector
11504 return Has_Inferable_Discriminants
(Prefix
(N
))
11505 and then Has_Inferable_Discriminants
(Selector_Name
(N
));
11508 -- The call to Has_Inferable_Discriminants will determine whether
11509 -- the selector has a constrained Unchecked_Union nominal type.
11512 return Has_Inferable_Discriminants
(Selector_Name
(N
));
11515 -- A qualified expression has inferable discriminants if its subtype
11516 -- mark is a constrained Unchecked_Union subtype.
11518 elsif Nkind
(N
) = N_Qualified_Expression
then
11519 return Is_Unchecked_Union
(Etype
(Subtype_Mark
(N
)))
11520 and then Is_Constrained
(Etype
(Subtype_Mark
(N
)));
11522 -- For all other names, it is sufficient to have a constrained
11523 -- Unchecked_Union nominal subtype.
11526 return Is_Unchecked_Union
(Base_Type
(Etype
(N
)))
11527 and then Is_Constrained
(Etype
(N
));
11529 end Has_Inferable_Discriminants
;
11531 -------------------------------
11532 -- Insert_Dereference_Action --
11533 -------------------------------
11535 procedure Insert_Dereference_Action
(N
: Node_Id
) is
11537 function Is_Checked_Storage_Pool
(P
: Entity_Id
) return Boolean;
11538 -- Return true if type of P is derived from Checked_Pool;
11540 -----------------------------
11541 -- Is_Checked_Storage_Pool --
11542 -----------------------------
11544 function Is_Checked_Storage_Pool
(P
: Entity_Id
) return Boolean is
11553 while T
/= Etype
(T
) loop
11554 if Is_RTE
(T
, RE_Checked_Pool
) then
11562 end Is_Checked_Storage_Pool
;
11566 Typ
: constant Entity_Id
:= Etype
(N
);
11567 Desig
: constant Entity_Id
:= Available_View
(Designated_Type
(Typ
));
11568 Loc
: constant Source_Ptr
:= Sloc
(N
);
11569 Pool
: constant Entity_Id
:= Associated_Storage_Pool
(Typ
);
11570 Pnod
: constant Node_Id
:= Parent
(N
);
11578 -- Start of processing for Insert_Dereference_Action
11581 pragma Assert
(Nkind
(Pnod
) = N_Explicit_Dereference
);
11583 -- Do not re-expand a dereference which has already been processed by
11586 if Has_Dereference_Action
(Pnod
) then
11589 -- Do not perform this type of expansion for internally-generated
11592 elsif not Comes_From_Source
(Original_Node
(Pnod
)) then
11595 -- A dereference action is only applicable to objects which have been
11596 -- allocated on a checked pool.
11598 elsif not Is_Checked_Storage_Pool
(Pool
) then
11602 -- Extract the address of the dereferenced object. Generate:
11604 -- Addr : System.Address := <N>'Pool_Address;
11606 Addr
:= Make_Temporary
(Loc
, 'P');
11609 Make_Object_Declaration
(Loc
,
11610 Defining_Identifier
=> Addr
,
11611 Object_Definition
=>
11612 New_Occurrence_Of
(RTE
(RE_Address
), Loc
),
11614 Make_Attribute_Reference
(Loc
,
11615 Prefix
=> Duplicate_Subexpr_Move_Checks
(N
),
11616 Attribute_Name
=> Name_Pool_Address
)));
11618 -- Calculate the size of the dereferenced object. Generate:
11620 -- Size : Storage_Count := <N>.all'Size / Storage_Unit;
11623 Make_Explicit_Dereference
(Loc
,
11624 Prefix
=> Duplicate_Subexpr_Move_Checks
(N
));
11625 Set_Has_Dereference_Action
(Deref
);
11627 Size
:= Make_Temporary
(Loc
, 'S');
11630 Make_Object_Declaration
(Loc
,
11631 Defining_Identifier
=> Size
,
11633 Object_Definition
=>
11634 New_Occurrence_Of
(RTE
(RE_Storage_Count
), Loc
),
11637 Make_Op_Divide
(Loc
,
11639 Make_Attribute_Reference
(Loc
,
11641 Attribute_Name
=> Name_Size
),
11643 Make_Integer_Literal
(Loc
, System_Storage_Unit
))));
11645 -- Calculate the alignment of the dereferenced object. Generate:
11646 -- Alig : constant Storage_Count := <N>.all'Alignment;
11649 Make_Explicit_Dereference
(Loc
,
11650 Prefix
=> Duplicate_Subexpr_Move_Checks
(N
));
11651 Set_Has_Dereference_Action
(Deref
);
11653 Alig
:= Make_Temporary
(Loc
, 'A');
11656 Make_Object_Declaration
(Loc
,
11657 Defining_Identifier
=> Alig
,
11658 Object_Definition
=>
11659 New_Occurrence_Of
(RTE
(RE_Storage_Count
), Loc
),
11661 Make_Attribute_Reference
(Loc
,
11663 Attribute_Name
=> Name_Alignment
)));
11665 -- A dereference of a controlled object requires special processing. The
11666 -- finalization machinery requests additional space from the underlying
11667 -- pool to allocate and hide two pointers. As a result, a checked pool
11668 -- may mark the wrong memory as valid. Since checked pools do not have
11669 -- knowledge of hidden pointers, we have to bring the two pointers back
11670 -- in view in order to restore the original state of the object.
11672 if Needs_Finalization
(Desig
) then
11674 -- Adjust the address and size of the dereferenced object. Generate:
11675 -- Adjust_Controlled_Dereference (Addr, Size, Alig);
11678 Make_Procedure_Call_Statement
(Loc
,
11680 New_Occurrence_Of
(RTE
(RE_Adjust_Controlled_Dereference
), Loc
),
11681 Parameter_Associations
=> New_List
(
11682 New_Occurrence_Of
(Addr
, Loc
),
11683 New_Occurrence_Of
(Size
, Loc
),
11684 New_Occurrence_Of
(Alig
, Loc
)));
11686 -- Class-wide types complicate things because we cannot determine
11687 -- statically whether the actual object is truly controlled. We must
11688 -- generate a runtime check to detect this property. Generate:
11690 -- if Needs_Finalization (<N>.all'Tag) then
11694 if Is_Class_Wide_Type
(Desig
) then
11696 Make_Explicit_Dereference
(Loc
,
11697 Prefix
=> Duplicate_Subexpr_Move_Checks
(N
));
11698 Set_Has_Dereference_Action
(Deref
);
11701 Make_Implicit_If_Statement
(N
,
11703 Make_Function_Call
(Loc
,
11705 New_Occurrence_Of
(RTE
(RE_Needs_Finalization
), Loc
),
11706 Parameter_Associations
=> New_List
(
11707 Make_Attribute_Reference
(Loc
,
11709 Attribute_Name
=> Name_Tag
))),
11710 Then_Statements
=> New_List
(Stmt
));
11713 Insert_Action
(N
, Stmt
);
11717 -- Dereference (Pool, Addr, Size, Alig);
11720 Make_Procedure_Call_Statement
(Loc
,
11723 (Find_Prim_Op
(Etype
(Pool
), Name_Dereference
), Loc
),
11724 Parameter_Associations
=> New_List
(
11725 New_Occurrence_Of
(Pool
, Loc
),
11726 New_Occurrence_Of
(Addr
, Loc
),
11727 New_Occurrence_Of
(Size
, Loc
),
11728 New_Occurrence_Of
(Alig
, Loc
))));
11730 -- Mark the explicit dereference as processed to avoid potential
11731 -- infinite expansion.
11733 Set_Has_Dereference_Action
(Pnod
);
11736 when RE_Not_Available
=>
11738 end Insert_Dereference_Action
;
11740 --------------------------------
11741 -- Integer_Promotion_Possible --
11742 --------------------------------
11744 function Integer_Promotion_Possible
(N
: Node_Id
) return Boolean is
11745 Operand
: constant Node_Id
:= Expression
(N
);
11746 Operand_Type
: constant Entity_Id
:= Etype
(Operand
);
11747 Root_Operand_Type
: constant Entity_Id
:= Root_Type
(Operand_Type
);
11750 pragma Assert
(Nkind
(N
) = N_Type_Conversion
);
11754 -- We only do the transformation for source constructs. We assume
11755 -- that the expander knows what it is doing when it generates code.
11757 Comes_From_Source
(N
)
11759 -- If the operand type is Short_Integer or Short_Short_Integer,
11760 -- then we will promote to Integer, which is available on all
11761 -- targets, and is sufficient to ensure no intermediate overflow.
11762 -- Furthermore it is likely to be as efficient or more efficient
11763 -- than using the smaller type for the computation so we do this
11764 -- unconditionally.
11767 (Root_Operand_Type
= Base_Type
(Standard_Short_Integer
)
11769 Root_Operand_Type
= Base_Type
(Standard_Short_Short_Integer
))
11771 -- Test for interesting operation, which includes addition,
11772 -- division, exponentiation, multiplication, subtraction, absolute
11773 -- value and unary negation. Unary "+" is omitted since it is a
11774 -- no-op and thus can't overflow.
11776 and then Nkind_In
(Operand
, N_Op_Abs
,
11783 end Integer_Promotion_Possible
;
11785 ------------------------------
11786 -- Make_Array_Comparison_Op --
11787 ------------------------------
11789 -- This is a hand-coded expansion of the following generic function:
11792 -- type elem is (<>);
11793 -- type index is (<>);
11794 -- type a is array (index range <>) of elem;
11796 -- function Gnnn (X : a; Y: a) return boolean is
11797 -- J : index := Y'first;
11800 -- if X'length = 0 then
11803 -- elsif Y'length = 0 then
11807 -- for I in X'range loop
11808 -- if X (I) = Y (J) then
11809 -- if J = Y'last then
11812 -- J := index'succ (J);
11816 -- return X (I) > Y (J);
11820 -- return X'length > Y'length;
11824 -- Note that since we are essentially doing this expansion by hand, we
11825 -- do not need to generate an actual or formal generic part, just the
11826 -- instantiated function itself.
11828 -- Perhaps we could have the actual generic available in the run-time,
11829 -- obtained by rtsfind, and actually expand a real instantiation ???
11831 function Make_Array_Comparison_Op
11833 Nod
: Node_Id
) return Node_Id
11835 Loc
: constant Source_Ptr
:= Sloc
(Nod
);
11837 X
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uX
);
11838 Y
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uY
);
11839 I
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uI
);
11840 J
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uJ
);
11842 Index
: constant Entity_Id
:= Base_Type
(Etype
(First_Index
(Typ
)));
11844 Loop_Statement
: Node_Id
;
11845 Loop_Body
: Node_Id
;
11847 Inner_If
: Node_Id
;
11848 Final_Expr
: Node_Id
;
11849 Func_Body
: Node_Id
;
11850 Func_Name
: Entity_Id
;
11856 -- if J = Y'last then
11859 -- J := index'succ (J);
11863 Make_Implicit_If_Statement
(Nod
,
11866 Left_Opnd
=> New_Occurrence_Of
(J
, Loc
),
11868 Make_Attribute_Reference
(Loc
,
11869 Prefix
=> New_Occurrence_Of
(Y
, Loc
),
11870 Attribute_Name
=> Name_Last
)),
11872 Then_Statements
=> New_List
(
11873 Make_Exit_Statement
(Loc
)),
11877 Make_Assignment_Statement
(Loc
,
11878 Name
=> New_Occurrence_Of
(J
, Loc
),
11880 Make_Attribute_Reference
(Loc
,
11881 Prefix
=> New_Occurrence_Of
(Index
, Loc
),
11882 Attribute_Name
=> Name_Succ
,
11883 Expressions
=> New_List
(New_Occurrence_Of
(J
, Loc
))))));
11885 -- if X (I) = Y (J) then
11888 -- return X (I) > Y (J);
11892 Make_Implicit_If_Statement
(Nod
,
11896 Make_Indexed_Component
(Loc
,
11897 Prefix
=> New_Occurrence_Of
(X
, Loc
),
11898 Expressions
=> New_List
(New_Occurrence_Of
(I
, Loc
))),
11901 Make_Indexed_Component
(Loc
,
11902 Prefix
=> New_Occurrence_Of
(Y
, Loc
),
11903 Expressions
=> New_List
(New_Occurrence_Of
(J
, Loc
)))),
11905 Then_Statements
=> New_List
(Inner_If
),
11907 Else_Statements
=> New_List
(
11908 Make_Simple_Return_Statement
(Loc
,
11912 Make_Indexed_Component
(Loc
,
11913 Prefix
=> New_Occurrence_Of
(X
, Loc
),
11914 Expressions
=> New_List
(New_Occurrence_Of
(I
, Loc
))),
11917 Make_Indexed_Component
(Loc
,
11918 Prefix
=> New_Occurrence_Of
(Y
, Loc
),
11919 Expressions
=> New_List
(
11920 New_Occurrence_Of
(J
, Loc
)))))));
11922 -- for I in X'range loop
11927 Make_Implicit_Loop_Statement
(Nod
,
11928 Identifier
=> Empty
,
11930 Iteration_Scheme
=>
11931 Make_Iteration_Scheme
(Loc
,
11932 Loop_Parameter_Specification
=>
11933 Make_Loop_Parameter_Specification
(Loc
,
11934 Defining_Identifier
=> I
,
11935 Discrete_Subtype_Definition
=>
11936 Make_Attribute_Reference
(Loc
,
11937 Prefix
=> New_Occurrence_Of
(X
, Loc
),
11938 Attribute_Name
=> Name_Range
))),
11940 Statements
=> New_List
(Loop_Body
));
11942 -- if X'length = 0 then
11944 -- elsif Y'length = 0 then
11947 -- for ... loop ... end loop;
11948 -- return X'length > Y'length;
11952 Make_Attribute_Reference
(Loc
,
11953 Prefix
=> New_Occurrence_Of
(X
, Loc
),
11954 Attribute_Name
=> Name_Length
);
11957 Make_Attribute_Reference
(Loc
,
11958 Prefix
=> New_Occurrence_Of
(Y
, Loc
),
11959 Attribute_Name
=> Name_Length
);
11963 Left_Opnd
=> Length1
,
11964 Right_Opnd
=> Length2
);
11967 Make_Implicit_If_Statement
(Nod
,
11971 Make_Attribute_Reference
(Loc
,
11972 Prefix
=> New_Occurrence_Of
(X
, Loc
),
11973 Attribute_Name
=> Name_Length
),
11975 Make_Integer_Literal
(Loc
, 0)),
11979 Make_Simple_Return_Statement
(Loc
,
11980 Expression
=> New_Occurrence_Of
(Standard_False
, Loc
))),
11982 Elsif_Parts
=> New_List
(
11983 Make_Elsif_Part
(Loc
,
11987 Make_Attribute_Reference
(Loc
,
11988 Prefix
=> New_Occurrence_Of
(Y
, Loc
),
11989 Attribute_Name
=> Name_Length
),
11991 Make_Integer_Literal
(Loc
, 0)),
11995 Make_Simple_Return_Statement
(Loc
,
11996 Expression
=> New_Occurrence_Of
(Standard_True
, Loc
))))),
11998 Else_Statements
=> New_List
(
12000 Make_Simple_Return_Statement
(Loc
,
12001 Expression
=> Final_Expr
)));
12005 Formals
:= New_List
(
12006 Make_Parameter_Specification
(Loc
,
12007 Defining_Identifier
=> X
,
12008 Parameter_Type
=> New_Occurrence_Of
(Typ
, Loc
)),
12010 Make_Parameter_Specification
(Loc
,
12011 Defining_Identifier
=> Y
,
12012 Parameter_Type
=> New_Occurrence_Of
(Typ
, Loc
)));
12014 -- function Gnnn (...) return boolean is
12015 -- J : index := Y'first;
12020 Func_Name
:= Make_Temporary
(Loc
, 'G');
12023 Make_Subprogram_Body
(Loc
,
12025 Make_Function_Specification
(Loc
,
12026 Defining_Unit_Name
=> Func_Name
,
12027 Parameter_Specifications
=> Formals
,
12028 Result_Definition
=> New_Occurrence_Of
(Standard_Boolean
, Loc
)),
12030 Declarations
=> New_List
(
12031 Make_Object_Declaration
(Loc
,
12032 Defining_Identifier
=> J
,
12033 Object_Definition
=> New_Occurrence_Of
(Index
, Loc
),
12035 Make_Attribute_Reference
(Loc
,
12036 Prefix
=> New_Occurrence_Of
(Y
, Loc
),
12037 Attribute_Name
=> Name_First
))),
12039 Handled_Statement_Sequence
=>
12040 Make_Handled_Sequence_Of_Statements
(Loc
,
12041 Statements
=> New_List
(If_Stat
)));
12044 end Make_Array_Comparison_Op
;
12046 ---------------------------
12047 -- Make_Boolean_Array_Op --
12048 ---------------------------
12050 -- For logical operations on boolean arrays, expand in line the following,
12051 -- replacing 'and' with 'or' or 'xor' where needed:
12053 -- function Annn (A : typ; B: typ) return typ is
12056 -- for J in A'range loop
12057 -- C (J) := A (J) op B (J);
12062 -- Here typ is the boolean array type
12064 function Make_Boolean_Array_Op
12066 N
: Node_Id
) return Node_Id
12068 Loc
: constant Source_Ptr
:= Sloc
(N
);
12070 A
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uA
);
12071 B
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uB
);
12072 C
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uC
);
12073 J
: constant Entity_Id
:= Make_Defining_Identifier
(Loc
, Name_uJ
);
12081 Func_Name
: Entity_Id
;
12082 Func_Body
: Node_Id
;
12083 Loop_Statement
: Node_Id
;
12087 Make_Indexed_Component
(Loc
,
12088 Prefix
=> New_Occurrence_Of
(A
, Loc
),
12089 Expressions
=> New_List
(New_Occurrence_Of
(J
, Loc
)));
12092 Make_Indexed_Component
(Loc
,
12093 Prefix
=> New_Occurrence_Of
(B
, Loc
),
12094 Expressions
=> New_List
(New_Occurrence_Of
(J
, Loc
)));
12097 Make_Indexed_Component
(Loc
,
12098 Prefix
=> New_Occurrence_Of
(C
, Loc
),
12099 Expressions
=> New_List
(New_Occurrence_Of
(J
, Loc
)));
12101 if Nkind
(N
) = N_Op_And
then
12105 Right_Opnd
=> B_J
);
12107 elsif Nkind
(N
) = N_Op_Or
then
12111 Right_Opnd
=> B_J
);
12117 Right_Opnd
=> B_J
);
12121 Make_Implicit_Loop_Statement
(N
,
12122 Identifier
=> Empty
,
12124 Iteration_Scheme
=>
12125 Make_Iteration_Scheme
(Loc
,
12126 Loop_Parameter_Specification
=>
12127 Make_Loop_Parameter_Specification
(Loc
,
12128 Defining_Identifier
=> J
,
12129 Discrete_Subtype_Definition
=>
12130 Make_Attribute_Reference
(Loc
,
12131 Prefix
=> New_Occurrence_Of
(A
, Loc
),
12132 Attribute_Name
=> Name_Range
))),
12134 Statements
=> New_List
(
12135 Make_Assignment_Statement
(Loc
,
12137 Expression
=> Op
)));
12139 Formals
:= New_List
(
12140 Make_Parameter_Specification
(Loc
,
12141 Defining_Identifier
=> A
,
12142 Parameter_Type
=> New_Occurrence_Of
(Typ
, Loc
)),
12144 Make_Parameter_Specification
(Loc
,
12145 Defining_Identifier
=> B
,
12146 Parameter_Type
=> New_Occurrence_Of
(Typ
, Loc
)));
12148 Func_Name
:= Make_Temporary
(Loc
, 'A');
12149 Set_Is_Inlined
(Func_Name
);
12152 Make_Subprogram_Body
(Loc
,
12154 Make_Function_Specification
(Loc
,
12155 Defining_Unit_Name
=> Func_Name
,
12156 Parameter_Specifications
=> Formals
,
12157 Result_Definition
=> New_Occurrence_Of
(Typ
, Loc
)),
12159 Declarations
=> New_List
(
12160 Make_Object_Declaration
(Loc
,
12161 Defining_Identifier
=> C
,
12162 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
))),
12164 Handled_Statement_Sequence
=>
12165 Make_Handled_Sequence_Of_Statements
(Loc
,
12166 Statements
=> New_List
(
12168 Make_Simple_Return_Statement
(Loc
,
12169 Expression
=> New_Occurrence_Of
(C
, Loc
)))));
12172 end Make_Boolean_Array_Op
;
12174 -----------------------------------------
12175 -- Minimized_Eliminated_Overflow_Check --
12176 -----------------------------------------
12178 function Minimized_Eliminated_Overflow_Check
(N
: Node_Id
) return Boolean is
12181 Is_Signed_Integer_Type
(Etype
(N
))
12182 and then Overflow_Check_Mode
in Minimized_Or_Eliminated
;
12183 end Minimized_Eliminated_Overflow_Check
;
12185 --------------------------------
12186 -- Optimize_Length_Comparison --
12187 --------------------------------
12189 procedure Optimize_Length_Comparison
(N
: Node_Id
) is
12190 Loc
: constant Source_Ptr
:= Sloc
(N
);
12191 Typ
: constant Entity_Id
:= Etype
(N
);
12196 -- First and Last attribute reference nodes, which end up as left and
12197 -- right operands of the optimized result.
12200 -- True for comparison operand of zero
12203 -- Comparison operand, set only if Is_Zero is false
12206 -- Entity whose length is being compared
12209 -- Integer_Literal node for length attribute expression, or Empty
12210 -- if there is no such expression present.
12213 -- Type of array index to which 'Length is applied
12215 Op
: Node_Kind
:= Nkind
(N
);
12216 -- Kind of comparison operator, gets flipped if operands backwards
12218 function Is_Optimizable
(N
: Node_Id
) return Boolean;
12219 -- Tests N to see if it is an optimizable comparison value (defined as
12220 -- constant zero or one, or something else where the value is known to
12221 -- be positive and in the range of 32-bits, and where the corresponding
12222 -- Length value is also known to be 32-bits. If result is true, sets
12223 -- Is_Zero, Ityp, and Comp accordingly.
12225 function Is_Entity_Length
(N
: Node_Id
) return Boolean;
12226 -- Tests if N is a length attribute applied to a simple entity. If so,
12227 -- returns True, and sets Ent to the entity, and Index to the integer
12228 -- literal provided as an attribute expression, or to Empty if none.
12229 -- Also returns True if the expression is a generated type conversion
12230 -- whose expression is of the desired form. This latter case arises
12231 -- when Apply_Universal_Integer_Attribute_Check installs a conversion
12232 -- to check for being in range, which is not needed in this context.
12233 -- Returns False if neither condition holds.
12235 function Prepare_64
(N
: Node_Id
) return Node_Id
;
12236 -- Given a discrete expression, returns a Long_Long_Integer typed
12237 -- expression representing the underlying value of the expression.
12238 -- This is done with an unchecked conversion to the result type. We
12239 -- use unchecked conversion to handle the enumeration type case.
12241 ----------------------
12242 -- Is_Entity_Length --
12243 ----------------------
12245 function Is_Entity_Length
(N
: Node_Id
) return Boolean is
12247 if Nkind
(N
) = N_Attribute_Reference
12248 and then Attribute_Name
(N
) = Name_Length
12249 and then Is_Entity_Name
(Prefix
(N
))
12251 Ent
:= Entity
(Prefix
(N
));
12253 if Present
(Expressions
(N
)) then
12254 Index
:= First
(Expressions
(N
));
12261 elsif Nkind
(N
) = N_Type_Conversion
12262 and then not Comes_From_Source
(N
)
12264 return Is_Entity_Length
(Expression
(N
));
12269 end Is_Entity_Length
;
12271 --------------------
12272 -- Is_Optimizable --
12273 --------------------
12275 function Is_Optimizable
(N
: Node_Id
) return Boolean is
12283 if Compile_Time_Known_Value
(N
) then
12284 Val
:= Expr_Value
(N
);
12286 if Val
= Uint_0
then
12291 elsif Val
= Uint_1
then
12298 -- Here we have to make sure of being within 32-bits
12300 Determine_Range
(N
, OK
, Lo
, Hi
, Assume_Valid
=> True);
12303 or else Lo
< Uint_1
12304 or else Hi
> UI_From_Int
(Int
'Last)
12309 -- Comparison value was within range, so now we must check the index
12310 -- value to make sure it is also within 32-bits.
12312 Indx
:= First_Index
(Etype
(Ent
));
12314 if Present
(Index
) then
12315 for J
in 2 .. UI_To_Int
(Intval
(Index
)) loop
12320 Ityp
:= Etype
(Indx
);
12322 if Esize
(Ityp
) > 32 then
12329 end Is_Optimizable
;
12335 function Prepare_64
(N
: Node_Id
) return Node_Id
is
12337 return Unchecked_Convert_To
(Standard_Long_Long_Integer
, N
);
12340 -- Start of processing for Optimize_Length_Comparison
12343 -- Nothing to do if not a comparison
12345 if Op
not in N_Op_Compare
then
12349 -- Nothing to do if special -gnatd.P debug flag set
12351 if Debug_Flag_Dot_PP
then
12355 -- Ent'Length op 0/1
12357 if Is_Entity_Length
(Left_Opnd
(N
))
12358 and then Is_Optimizable
(Right_Opnd
(N
))
12362 -- 0/1 op Ent'Length
12364 elsif Is_Entity_Length
(Right_Opnd
(N
))
12365 and then Is_Optimizable
(Left_Opnd
(N
))
12367 -- Flip comparison to opposite sense
12370 when N_Op_Lt
=> Op
:= N_Op_Gt
;
12371 when N_Op_Le
=> Op
:= N_Op_Ge
;
12372 when N_Op_Gt
=> Op
:= N_Op_Lt
;
12373 when N_Op_Ge
=> Op
:= N_Op_Le
;
12374 when others => null;
12377 -- Else optimization not possible
12383 -- Fall through if we will do the optimization
12385 -- Cases to handle:
12387 -- X'Length = 0 => X'First > X'Last
12388 -- X'Length = 1 => X'First = X'Last
12389 -- X'Length = n => X'First + (n - 1) = X'Last
12391 -- X'Length /= 0 => X'First <= X'Last
12392 -- X'Length /= 1 => X'First /= X'Last
12393 -- X'Length /= n => X'First + (n - 1) /= X'Last
12395 -- X'Length >= 0 => always true, warn
12396 -- X'Length >= 1 => X'First <= X'Last
12397 -- X'Length >= n => X'First + (n - 1) <= X'Last
12399 -- X'Length > 0 => X'First <= X'Last
12400 -- X'Length > 1 => X'First < X'Last
12401 -- X'Length > n => X'First + (n - 1) < X'Last
12403 -- X'Length <= 0 => X'First > X'Last (warn, could be =)
12404 -- X'Length <= 1 => X'First >= X'Last
12405 -- X'Length <= n => X'First + (n - 1) >= X'Last
12407 -- X'Length < 0 => always false (warn)
12408 -- X'Length < 1 => X'First > X'Last
12409 -- X'Length < n => X'First + (n - 1) > X'Last
12411 -- Note: for the cases of n (not constant 0,1), we require that the
12412 -- corresponding index type be integer or shorter (i.e. not 64-bit),
12413 -- and the same for the comparison value. Then we do the comparison
12414 -- using 64-bit arithmetic (actually long long integer), so that we
12415 -- cannot have overflow intefering with the result.
12417 -- First deal with warning cases
12426 Convert_To
(Typ
, New_Occurrence_Of
(Standard_True
, Loc
)));
12427 Analyze_And_Resolve
(N
, Typ
);
12428 Warn_On_Known_Condition
(N
);
12435 Convert_To
(Typ
, New_Occurrence_Of
(Standard_False
, Loc
)));
12436 Analyze_And_Resolve
(N
, Typ
);
12437 Warn_On_Known_Condition
(N
);
12441 if Constant_Condition_Warnings
12442 and then Comes_From_Source
(Original_Node
(N
))
12444 Error_Msg_N
("could replace by ""'=""?c?", N
);
12454 -- Build the First reference we will use
12457 Make_Attribute_Reference
(Loc
,
12458 Prefix
=> New_Occurrence_Of
(Ent
, Loc
),
12459 Attribute_Name
=> Name_First
);
12461 if Present
(Index
) then
12462 Set_Expressions
(Left
, New_List
(New_Copy
(Index
)));
12465 -- If general value case, then do the addition of (n - 1), and
12466 -- also add the needed conversions to type Long_Long_Integer.
12468 if Present
(Comp
) then
12471 Left_Opnd
=> Prepare_64
(Left
),
12473 Make_Op_Subtract
(Loc
,
12474 Left_Opnd
=> Prepare_64
(Comp
),
12475 Right_Opnd
=> Make_Integer_Literal
(Loc
, 1)));
12478 -- Build the Last reference we will use
12481 Make_Attribute_Reference
(Loc
,
12482 Prefix
=> New_Occurrence_Of
(Ent
, Loc
),
12483 Attribute_Name
=> Name_Last
);
12485 if Present
(Index
) then
12486 Set_Expressions
(Right
, New_List
(New_Copy
(Index
)));
12489 -- If general operand, convert Last reference to Long_Long_Integer
12491 if Present
(Comp
) then
12492 Right
:= Prepare_64
(Right
);
12495 -- Check for cases to optimize
12497 -- X'Length = 0 => X'First > X'Last
12498 -- X'Length < 1 => X'First > X'Last
12499 -- X'Length < n => X'First + (n - 1) > X'Last
12501 if (Is_Zero
and then Op
= N_Op_Eq
)
12502 or else (not Is_Zero
and then Op
= N_Op_Lt
)
12507 Right_Opnd
=> Right
);
12509 -- X'Length = 1 => X'First = X'Last
12510 -- X'Length = n => X'First + (n - 1) = X'Last
12512 elsif not Is_Zero
and then Op
= N_Op_Eq
then
12516 Right_Opnd
=> Right
);
12518 -- X'Length /= 0 => X'First <= X'Last
12519 -- X'Length > 0 => X'First <= X'Last
12521 elsif Is_Zero
and (Op
= N_Op_Ne
or else Op
= N_Op_Gt
) then
12525 Right_Opnd
=> Right
);
12527 -- X'Length /= 1 => X'First /= X'Last
12528 -- X'Length /= n => X'First + (n - 1) /= X'Last
12530 elsif not Is_Zero
and then Op
= N_Op_Ne
then
12534 Right_Opnd
=> Right
);
12536 -- X'Length >= 1 => X'First <= X'Last
12537 -- X'Length >= n => X'First + (n - 1) <= X'Last
12539 elsif not Is_Zero
and then Op
= N_Op_Ge
then
12543 Right_Opnd
=> Right
);
12545 -- X'Length > 1 => X'First < X'Last
12546 -- X'Length > n => X'First + (n = 1) < X'Last
12548 elsif not Is_Zero
and then Op
= N_Op_Gt
then
12552 Right_Opnd
=> Right
);
12554 -- X'Length <= 1 => X'First >= X'Last
12555 -- X'Length <= n => X'First + (n - 1) >= X'Last
12557 elsif not Is_Zero
and then Op
= N_Op_Le
then
12561 Right_Opnd
=> Right
);
12563 -- Should not happen at this stage
12566 raise Program_Error
;
12569 -- Rewrite and finish up
12571 Rewrite
(N
, Result
);
12572 Analyze_And_Resolve
(N
, Typ
);
12574 end Optimize_Length_Comparison
;
12576 ------------------------------
12577 -- Process_Transient_Object --
12578 ------------------------------
12580 procedure Process_Transient_Object
12582 Rel_Node
: Node_Id
)
12584 Loc
: constant Source_Ptr
:= Sloc
(Decl
);
12585 Obj_Id
: constant Entity_Id
:= Defining_Identifier
(Decl
);
12586 Obj_Typ
: constant Node_Id
:= Etype
(Obj_Id
);
12587 Desig_Typ
: Entity_Id
;
12589 Fin_Stmts
: List_Id
;
12590 Ptr_Id
: Entity_Id
;
12591 Temp_Id
: Entity_Id
;
12592 Temp_Ins
: Node_Id
;
12594 Hook_Context
: constant Node_Id
:= Find_Hook_Context
(Rel_Node
);
12595 -- Node on which to insert the hook pointer (as an action): the
12596 -- innermost enclosing non-transient scope.
12598 Finalization_Context
: Node_Id
;
12599 -- Node after which to insert finalization actions
12601 Finalize_Always
: Boolean;
12602 -- If False, call to finalizer includes a test of whether the hook
12603 -- pointer is null.
12606 -- Step 0: determine where to attach finalization actions in the tree
12608 -- Special case for Boolean EWAs: capture expression in a temporary,
12609 -- whose declaration will serve as the context around which to insert
12610 -- finalization code. The finalization thus remains local to the
12611 -- specific condition being evaluated.
12613 if Is_Boolean_Type
(Etype
(Rel_Node
)) then
12615 -- In this case, the finalization context is chosen so that we know
12616 -- at finalization point that the hook pointer is never null, so no
12617 -- need for a test, we can call the finalizer unconditionally, except
12618 -- in the case where the object is created in a specific branch of a
12619 -- conditional expression.
12622 not Within_Case_Or_If_Expression
(Rel_Node
)
12623 and then not Nkind_In
12624 (Original_Node
(Rel_Node
), N_Case_Expression
,
12628 Loc
: constant Source_Ptr
:= Sloc
(Rel_Node
);
12629 Temp
: constant Entity_Id
:= Make_Temporary
(Loc
, 'E', Rel_Node
);
12632 Append_To
(Actions
(Rel_Node
),
12633 Make_Object_Declaration
(Loc
,
12634 Defining_Identifier
=> Temp
,
12635 Constant_Present
=> True,
12636 Object_Definition
=>
12637 New_Occurrence_Of
(Etype
(Rel_Node
), Loc
),
12638 Expression
=> Expression
(Rel_Node
)));
12639 Finalization_Context
:= Last
(Actions
(Rel_Node
));
12641 Analyze
(Last
(Actions
(Rel_Node
)));
12643 Set_Expression
(Rel_Node
, New_Occurrence_Of
(Temp
, Loc
));
12644 Analyze
(Expression
(Rel_Node
));
12648 Finalize_Always
:= False;
12649 Finalization_Context
:= Hook_Context
;
12652 -- Step 1: Create the access type which provides a reference to the
12653 -- transient controlled object.
12655 if Is_Access_Type
(Obj_Typ
) then
12656 Desig_Typ
:= Directly_Designated_Type
(Obj_Typ
);
12658 Desig_Typ
:= Obj_Typ
;
12661 Desig_Typ
:= Base_Type
(Desig_Typ
);
12664 -- Ann : access [all] <Desig_Typ>;
12666 Ptr_Id
:= Make_Temporary
(Loc
, 'A');
12668 Insert_Action
(Hook_Context
,
12669 Make_Full_Type_Declaration
(Loc
,
12670 Defining_Identifier
=> Ptr_Id
,
12672 Make_Access_To_Object_Definition
(Loc
,
12673 All_Present
=> Ekind
(Obj_Typ
) = E_General_Access_Type
,
12674 Subtype_Indication
=> New_Occurrence_Of
(Desig_Typ
, Loc
))));
12676 -- Step 2: Create a temporary which acts as a hook to the transient
12677 -- controlled object. Generate:
12679 -- Temp : Ptr_Id := null;
12681 Temp_Id
:= Make_Temporary
(Loc
, 'T');
12683 Insert_Action
(Hook_Context
,
12684 Make_Object_Declaration
(Loc
,
12685 Defining_Identifier
=> Temp_Id
,
12686 Object_Definition
=> New_Occurrence_Of
(Ptr_Id
, Loc
)));
12688 -- Mark the temporary as created for the purposes of exporting the
12689 -- transient controlled object out of the expression_with_action or if
12690 -- expression. This signals the machinery in Build_Finalizer to treat
12691 -- this case specially.
12693 Set_Status_Flag_Or_Transient_Decl
(Temp_Id
, Decl
);
12695 -- Step 3: Hook the transient object to the temporary
12697 -- This must be inserted right after the object declaration, so that
12698 -- the assignment is executed if, and only if, the object is actually
12699 -- created (whereas the declaration of the hook pointer, and the
12700 -- finalization call, may be inserted at an outer level, and may
12701 -- remain unused for some executions, if the actual creation of
12702 -- the object is conditional).
12704 -- The use of unchecked conversion / unrestricted access is needed to
12705 -- avoid an accessibility violation. Note that the finalization code is
12706 -- structured in such a way that the "hook" is processed only when it
12707 -- points to an existing object.
12709 if Is_Access_Type
(Obj_Typ
) then
12711 Unchecked_Convert_To
(Ptr_Id
, New_Occurrence_Of
(Obj_Id
, Loc
));
12714 Make_Attribute_Reference
(Loc
,
12715 Prefix
=> New_Occurrence_Of
(Obj_Id
, Loc
),
12716 Attribute_Name
=> Name_Unrestricted_Access
);
12720 -- Temp := Ptr_Id (Obj_Id);
12722 -- Temp := Obj_Id'Unrestricted_Access;
12724 -- When the transient object is initialized by an aggregate, the hook
12725 -- must capture the object after the last component assignment takes
12726 -- place. Only then is the object fully initialized.
12728 if Ekind
(Obj_Id
) = E_Variable
12729 and then Present
(Last_Aggregate_Assignment
(Obj_Id
))
12731 Temp_Ins
:= Last_Aggregate_Assignment
(Obj_Id
);
12733 -- Otherwise the hook seizes the related object immediately
12739 Insert_After_And_Analyze
(Temp_Ins
,
12740 Make_Assignment_Statement
(Loc
,
12741 Name
=> New_Occurrence_Of
(Temp_Id
, Loc
),
12742 Expression
=> Expr
));
12744 -- Step 4: Finalize the transient controlled object after the context
12745 -- has been evaluated/elaborated. Generate:
12747 -- if Temp /= null then
12748 -- [Deep_]Finalize (Temp.all);
12752 -- When the node is part of a return statement, there is no need to
12753 -- insert a finalization call, as the general finalization mechanism
12754 -- (see Build_Finalizer) would take care of the transient controlled
12755 -- object on subprogram exit. Note that it would also be impossible to
12756 -- insert the finalization code after the return statement as this will
12757 -- render it unreachable.
12759 if Nkind
(Finalization_Context
) /= N_Simple_Return_Statement
then
12760 Fin_Stmts
:= New_List
(
12763 Make_Explicit_Dereference
(Loc
,
12764 Prefix
=> New_Occurrence_Of
(Temp_Id
, Loc
)),
12767 Make_Assignment_Statement
(Loc
,
12768 Name
=> New_Occurrence_Of
(Temp_Id
, Loc
),
12769 Expression
=> Make_Null
(Loc
)));
12771 if not Finalize_Always
then
12772 Fin_Stmts
:= New_List
(
12773 Make_Implicit_If_Statement
(Decl
,
12776 Left_Opnd
=> New_Occurrence_Of
(Temp_Id
, Loc
),
12777 Right_Opnd
=> Make_Null
(Loc
)),
12778 Then_Statements
=> Fin_Stmts
));
12781 Insert_Actions_After
(Finalization_Context
, Fin_Stmts
);
12783 end Process_Transient_Object
;
12785 ------------------------
12786 -- Rewrite_Comparison --
12787 ------------------------
12789 procedure Rewrite_Comparison
(N
: Node_Id
) is
12790 Warning_Generated
: Boolean := False;
12791 -- Set to True if first pass with Assume_Valid generates a warning in
12792 -- which case we skip the second pass to avoid warning overloaded.
12795 -- Set to Standard_True or Standard_False
12798 if Nkind
(N
) = N_Type_Conversion
then
12799 Rewrite_Comparison
(Expression
(N
));
12802 elsif Nkind
(N
) not in N_Op_Compare
then
12806 -- Now start looking at the comparison in detail. We potentially go
12807 -- through this loop twice. The first time, Assume_Valid is set False
12808 -- in the call to Compile_Time_Compare. If this call results in a
12809 -- clear result of always True or Always False, that's decisive and
12810 -- we are done. Otherwise we repeat the processing with Assume_Valid
12811 -- set to True to generate additional warnings. We can skip that step
12812 -- if Constant_Condition_Warnings is False.
12814 for AV
in False .. True loop
12816 Typ
: constant Entity_Id
:= Etype
(N
);
12817 Op1
: constant Node_Id
:= Left_Opnd
(N
);
12818 Op2
: constant Node_Id
:= Right_Opnd
(N
);
12820 Res
: constant Compare_Result
:=
12821 Compile_Time_Compare
(Op1
, Op2
, Assume_Valid
=> AV
);
12822 -- Res indicates if compare outcome can be compile time determined
12824 True_Result
: Boolean;
12825 False_Result
: Boolean;
12828 case N_Op_Compare
(Nkind
(N
)) is
12830 True_Result
:= Res
= EQ
;
12831 False_Result
:= Res
= LT
or else Res
= GT
or else Res
= NE
;
12834 True_Result
:= Res
in Compare_GE
;
12835 False_Result
:= Res
= LT
;
12838 and then Constant_Condition_Warnings
12839 and then Comes_From_Source
(Original_Node
(N
))
12840 and then Nkind
(Original_Node
(N
)) = N_Op_Ge
12841 and then not In_Instance
12842 and then Is_Integer_Type
(Etype
(Left_Opnd
(N
)))
12843 and then not Has_Warnings_Off
(Etype
(Left_Opnd
(N
)))
12846 ("can never be greater than, could replace by ""'=""?c?",
12848 Warning_Generated
:= True;
12852 True_Result
:= Res
= GT
;
12853 False_Result
:= Res
in Compare_LE
;
12856 True_Result
:= Res
= LT
;
12857 False_Result
:= Res
in Compare_GE
;
12860 True_Result
:= Res
in Compare_LE
;
12861 False_Result
:= Res
= GT
;
12864 and then Constant_Condition_Warnings
12865 and then Comes_From_Source
(Original_Node
(N
))
12866 and then Nkind
(Original_Node
(N
)) = N_Op_Le
12867 and then not In_Instance
12868 and then Is_Integer_Type
(Etype
(Left_Opnd
(N
)))
12869 and then not Has_Warnings_Off
(Etype
(Left_Opnd
(N
)))
12872 ("can never be less than, could replace by ""'=""?c?", N
);
12873 Warning_Generated
:= True;
12877 True_Result
:= Res
= NE
or else Res
= GT
or else Res
= LT
;
12878 False_Result
:= Res
= EQ
;
12881 -- If this is the first iteration, then we actually convert the
12882 -- comparison into True or False, if the result is certain.
12885 if True_Result
or False_Result
then
12886 Result
:= Boolean_Literals
(True_Result
);
12889 New_Occurrence_Of
(Result
, Sloc
(N
))));
12890 Analyze_And_Resolve
(N
, Typ
);
12891 Warn_On_Known_Condition
(N
);
12895 -- If this is the second iteration (AV = True), and the original
12896 -- node comes from source and we are not in an instance, then give
12897 -- a warning if we know result would be True or False. Note: we
12898 -- know Constant_Condition_Warnings is set if we get here.
12900 elsif Comes_From_Source
(Original_Node
(N
))
12901 and then not In_Instance
12903 if True_Result
then
12905 ("condition can only be False if invalid values present??",
12907 elsif False_Result
then
12909 ("condition can only be True if invalid values present??",
12915 -- Skip second iteration if not warning on constant conditions or
12916 -- if the first iteration already generated a warning of some kind or
12917 -- if we are in any case assuming all values are valid (so that the
12918 -- first iteration took care of the valid case).
12920 exit when not Constant_Condition_Warnings
;
12921 exit when Warning_Generated
;
12922 exit when Assume_No_Invalid_Values
;
12924 end Rewrite_Comparison
;
12926 ----------------------------
12927 -- Safe_In_Place_Array_Op --
12928 ----------------------------
12930 function Safe_In_Place_Array_Op
12933 Op2
: Node_Id
) return Boolean
12935 Target
: Entity_Id
;
12937 function Is_Safe_Operand
(Op
: Node_Id
) return Boolean;
12938 -- Operand is safe if it cannot overlap part of the target of the
12939 -- operation. If the operand and the target are identical, the operand
12940 -- is safe. The operand can be empty in the case of negation.
12942 function Is_Unaliased
(N
: Node_Id
) return Boolean;
12943 -- Check that N is a stand-alone entity
12949 function Is_Unaliased
(N
: Node_Id
) return Boolean is
12953 and then No
(Address_Clause
(Entity
(N
)))
12954 and then No
(Renamed_Object
(Entity
(N
)));
12957 ---------------------
12958 -- Is_Safe_Operand --
12959 ---------------------
12961 function Is_Safe_Operand
(Op
: Node_Id
) return Boolean is
12966 elsif Is_Entity_Name
(Op
) then
12967 return Is_Unaliased
(Op
);
12969 elsif Nkind_In
(Op
, N_Indexed_Component
, N_Selected_Component
) then
12970 return Is_Unaliased
(Prefix
(Op
));
12972 elsif Nkind
(Op
) = N_Slice
then
12974 Is_Unaliased
(Prefix
(Op
))
12975 and then Entity
(Prefix
(Op
)) /= Target
;
12977 elsif Nkind
(Op
) = N_Op_Not
then
12978 return Is_Safe_Operand
(Right_Opnd
(Op
));
12983 end Is_Safe_Operand
;
12985 -- Start of processing for Safe_In_Place_Array_Op
12988 -- Skip this processing if the component size is different from system
12989 -- storage unit (since at least for NOT this would cause problems).
12991 if Component_Size
(Etype
(Lhs
)) /= System_Storage_Unit
then
12994 -- Cannot do in place stuff on VM_Target since cannot pass addresses
12996 elsif VM_Target
/= No_VM
then
12999 -- Cannot do in place stuff if non-standard Boolean representation
13001 elsif Has_Non_Standard_Rep
(Component_Type
(Etype
(Lhs
))) then
13004 elsif not Is_Unaliased
(Lhs
) then
13008 Target
:= Entity
(Lhs
);
13009 return Is_Safe_Operand
(Op1
) and then Is_Safe_Operand
(Op2
);
13011 end Safe_In_Place_Array_Op
;
13013 -----------------------
13014 -- Tagged_Membership --
13015 -----------------------
13017 -- There are two different cases to consider depending on whether the right
13018 -- operand is a class-wide type or not. If not we just compare the actual
13019 -- tag of the left expr to the target type tag:
13021 -- Left_Expr.Tag = Right_Type'Tag;
13023 -- If it is a class-wide type we use the RT function CW_Membership which is
13024 -- usually implemented by looking in the ancestor tables contained in the
13025 -- dispatch table pointed by Left_Expr.Tag for Typ'Tag
13027 -- Ada 2005 (AI-251): If it is a class-wide interface type we use the RT
13028 -- function IW_Membership which is usually implemented by looking in the
13029 -- table of abstract interface types plus the ancestor table contained in
13030 -- the dispatch table pointed by Left_Expr.Tag for Typ'Tag
13032 procedure Tagged_Membership
13034 SCIL_Node
: out Node_Id
;
13035 Result
: out Node_Id
)
13037 Left
: constant Node_Id
:= Left_Opnd
(N
);
13038 Right
: constant Node_Id
:= Right_Opnd
(N
);
13039 Loc
: constant Source_Ptr
:= Sloc
(N
);
13041 Full_R_Typ
: Entity_Id
;
13042 Left_Type
: Entity_Id
;
13043 New_Node
: Node_Id
;
13044 Right_Type
: Entity_Id
;
13048 SCIL_Node
:= Empty
;
13050 -- Handle entities from the limited view
13052 Left_Type
:= Available_View
(Etype
(Left
));
13053 Right_Type
:= Available_View
(Etype
(Right
));
13055 -- In the case where the type is an access type, the test is applied
13056 -- using the designated types (needed in Ada 2012 for implicit anonymous
13057 -- access conversions, for AI05-0149).
13059 if Is_Access_Type
(Right_Type
) then
13060 Left_Type
:= Designated_Type
(Left_Type
);
13061 Right_Type
:= Designated_Type
(Right_Type
);
13064 if Is_Class_Wide_Type
(Left_Type
) then
13065 Left_Type
:= Root_Type
(Left_Type
);
13068 if Is_Class_Wide_Type
(Right_Type
) then
13069 Full_R_Typ
:= Underlying_Type
(Root_Type
(Right_Type
));
13071 Full_R_Typ
:= Underlying_Type
(Right_Type
);
13075 Make_Selected_Component
(Loc
,
13076 Prefix
=> Relocate_Node
(Left
),
13078 New_Occurrence_Of
(First_Tag_Component
(Left_Type
), Loc
));
13080 if Is_Class_Wide_Type
(Right_Type
) then
13082 -- No need to issue a run-time check if we statically know that the
13083 -- result of this membership test is always true. For example,
13084 -- considering the following declarations:
13086 -- type Iface is interface;
13087 -- type T is tagged null record;
13088 -- type DT is new T and Iface with null record;
13093 -- These membership tests are always true:
13096 -- Obj2 in T'Class;
13097 -- Obj2 in Iface'Class;
13099 -- We do not need to handle cases where the membership is illegal.
13102 -- Obj1 in DT'Class; -- Compile time error
13103 -- Obj1 in Iface'Class; -- Compile time error
13105 if not Is_Class_Wide_Type
(Left_Type
)
13106 and then (Is_Ancestor
(Etype
(Right_Type
), Left_Type
,
13107 Use_Full_View
=> True)
13108 or else (Is_Interface
(Etype
(Right_Type
))
13109 and then Interface_Present_In_Ancestor
13111 Iface
=> Etype
(Right_Type
))))
13113 Result
:= New_Occurrence_Of
(Standard_True
, Loc
);
13117 -- Ada 2005 (AI-251): Class-wide applied to interfaces
13119 if Is_Interface
(Etype
(Class_Wide_Type
(Right_Type
)))
13121 -- Support to: "Iface_CW_Typ in Typ'Class"
13123 or else Is_Interface
(Left_Type
)
13125 -- Issue error if IW_Membership operation not available in a
13126 -- configurable run time setting.
13128 if not RTE_Available
(RE_IW_Membership
) then
13130 ("dynamic membership test on interface types", N
);
13136 Make_Function_Call
(Loc
,
13137 Name
=> New_Occurrence_Of
(RTE
(RE_IW_Membership
), Loc
),
13138 Parameter_Associations
=> New_List
(
13139 Make_Attribute_Reference
(Loc
,
13141 Attribute_Name
=> Name_Address
),
13142 New_Occurrence_Of
(
13143 Node
(First_Elmt
(Access_Disp_Table
(Full_R_Typ
))),
13146 -- Ada 95: Normal case
13149 Build_CW_Membership
(Loc
,
13150 Obj_Tag_Node
=> Obj_Tag
,
13152 New_Occurrence_Of
(
13153 Node
(First_Elmt
(Access_Disp_Table
(Full_R_Typ
))), Loc
),
13155 New_Node
=> New_Node
);
13157 -- Generate the SCIL node for this class-wide membership test.
13158 -- Done here because the previous call to Build_CW_Membership
13159 -- relocates Obj_Tag.
13161 if Generate_SCIL
then
13162 SCIL_Node
:= Make_SCIL_Membership_Test
(Sloc
(N
));
13163 Set_SCIL_Entity
(SCIL_Node
, Etype
(Right_Type
));
13164 Set_SCIL_Tag_Value
(SCIL_Node
, Obj_Tag
);
13167 Result
:= New_Node
;
13170 -- Right_Type is not a class-wide type
13173 -- No need to check the tag of the object if Right_Typ is abstract
13175 if Is_Abstract_Type
(Right_Type
) then
13176 Result
:= New_Occurrence_Of
(Standard_False
, Loc
);
13181 Left_Opnd
=> Obj_Tag
,
13184 (Node
(First_Elmt
(Access_Disp_Table
(Full_R_Typ
))), Loc
));
13187 end Tagged_Membership
;
13189 ------------------------------
13190 -- Unary_Op_Validity_Checks --
13191 ------------------------------
13193 procedure Unary_Op_Validity_Checks
(N
: Node_Id
) is
13195 if Validity_Checks_On
and Validity_Check_Operands
then
13196 Ensure_Valid
(Right_Opnd
(N
));
13198 end Unary_Op_Validity_Checks
;