1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2008, 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 Einfo; use Einfo;
29 with Elists; use Elists;
30 with Errout; use Errout;
31 with Exp_Aggr; use Exp_Aggr;
32 with Exp_Atag; use Exp_Atag;
33 with Exp_Ch3; use Exp_Ch3;
34 with Exp_Ch6; use Exp_Ch6;
35 with Exp_Ch7; use Exp_Ch7;
36 with Exp_Ch9; use Exp_Ch9;
37 with Exp_Disp; use Exp_Disp;
38 with Exp_Fixd; use Exp_Fixd;
39 with Exp_Pakd; use Exp_Pakd;
40 with Exp_Tss; use Exp_Tss;
41 with Exp_Util; use Exp_Util;
42 with Exp_VFpt; use Exp_VFpt;
43 with Freeze; use Freeze;
44 with Inline; use Inline;
45 with Namet; use Namet;
46 with Nlists; use Nlists;
47 with Nmake; use Nmake;
49 with Restrict; use Restrict;
50 with Rident; use Rident;
51 with Rtsfind; use Rtsfind;
53 with Sem_Aux; use Sem_Aux;
54 with Sem_Cat; use Sem_Cat;
55 with Sem_Ch3; use Sem_Ch3;
56 with Sem_Ch8; use Sem_Ch8;
57 with Sem_Ch13; use Sem_Ch13;
58 with Sem_Eval; use Sem_Eval;
59 with Sem_Res; use Sem_Res;
60 with Sem_Type; use Sem_Type;
61 with Sem_Util; use Sem_Util;
62 with Sem_Warn; use Sem_Warn;
63 with Sinfo; use Sinfo;
64 with Snames; use Snames;
65 with Stand; use Stand;
66 with Targparm; use Targparm;
67 with Tbuild; use Tbuild;
68 with Ttypes; use Ttypes;
69 with Uintp; use Uintp;
70 with Urealp; use Urealp;
71 with Validsw; use Validsw;
73 package body Exp_Ch4 is
75 -----------------------
76 -- Local Subprograms --
77 -----------------------
79 procedure Binary_Op_Validity_Checks (N : Node_Id);
80 pragma Inline (Binary_Op_Validity_Checks);
81 -- Performs validity checks for a binary operator
83 procedure Build_Boolean_Array_Proc_Call
87 -- If a boolean array assignment can be done in place, build call to
88 -- corresponding library procedure.
90 procedure Displace_Allocator_Pointer (N : Node_Id);
91 -- Ada 2005 (AI-251): Subsidiary procedure to Expand_N_Allocator and
92 -- Expand_Allocator_Expression. Allocating class-wide interface objects
93 -- this routine displaces the pointer to the allocated object to reference
94 -- the component referencing the corresponding secondary dispatch table.
96 procedure Expand_Allocator_Expression (N : Node_Id);
97 -- Subsidiary to Expand_N_Allocator, for the case when the expression
98 -- is a qualified expression or an aggregate.
100 procedure Expand_Array_Comparison (N : Node_Id);
101 -- This routine handles expansion of the comparison operators (N_Op_Lt,
102 -- N_Op_Le, N_Op_Gt, N_Op_Ge) when operating on an array type. The basic
103 -- code for these operators is similar, differing only in the details of
104 -- the actual comparison call that is made. Special processing (call a
107 function Expand_Array_Equality
112 Typ : Entity_Id) return Node_Id;
113 -- Expand an array equality into a call to a function implementing this
114 -- equality, and a call to it. Loc is the location for the generated nodes.
115 -- Lhs and Rhs are the array expressions to be compared. Bodies is a list
116 -- on which to attach bodies of local functions that are created in the
117 -- process. It is the responsibility of the caller to insert those bodies
118 -- at the right place. Nod provides the Sloc value for the generated code.
119 -- Normally the types used for the generated equality routine are taken
120 -- from Lhs and Rhs. However, in some situations of generated code, the
121 -- Etype fields of Lhs and Rhs are not set yet. In such cases, Typ supplies
122 -- the type to be used for the formal parameters.
124 procedure Expand_Boolean_Operator (N : Node_Id);
125 -- Common expansion processing for Boolean operators (And, Or, Xor) for the
126 -- case of array type arguments.
128 function Expand_Composite_Equality
133 Bodies : List_Id) return Node_Id;
134 -- Local recursive function used to expand equality for nested composite
135 -- types. Used by Expand_Record/Array_Equality, Bodies is a list on which
136 -- to attach bodies of local functions that are created in the process.
137 -- This is the responsibility of the caller to insert those bodies at the
138 -- right place. Nod provides the Sloc value for generated code. Lhs and Rhs
139 -- are the left and right sides for the comparison, and Typ is the type of
140 -- the arrays to compare.
142 procedure Expand_Concatenate (Cnode : Node_Id; Opnds : List_Id);
143 -- Routine to expand concatenation of a sequence of two or more operands
144 -- (in the list Operands) and replace node Cnode with the result of the
145 -- concatenation. The operands can be of any appropriate type, and can
146 -- include both arrays and singleton elements.
148 procedure Fixup_Universal_Fixed_Operation (N : Node_Id);
149 -- N is a N_Op_Divide or N_Op_Multiply node whose result is universal
150 -- fixed. We do not have such a type at runtime, so the purpose of this
151 -- routine is to find the real type by looking up the tree. We also
152 -- determine if the operation must be rounded.
154 function Get_Allocator_Final_List
157 PtrT : Entity_Id) return Entity_Id;
158 -- If the designated type is controlled, build final_list expression for
159 -- created object. If context is an access parameter, create a local access
160 -- type to have a usable finalization list.
162 function Has_Inferable_Discriminants (N : Node_Id) return Boolean;
163 -- Ada 2005 (AI-216): A view of an Unchecked_Union object has inferable
164 -- discriminants if it has a constrained nominal type, unless the object
165 -- is a component of an enclosing Unchecked_Union object that is subject
166 -- to a per-object constraint and the enclosing object lacks inferable
169 -- An expression of an Unchecked_Union type has inferable discriminants
170 -- if it is either a name of an object with inferable discriminants or a
171 -- qualified expression whose subtype mark denotes a constrained subtype.
173 procedure Insert_Dereference_Action (N : Node_Id);
174 -- N is an expression whose type is an access. When the type of the
175 -- associated storage pool is derived from Checked_Pool, generate a
176 -- call to the 'Dereference' primitive operation.
178 function Make_Array_Comparison_Op
180 Nod : Node_Id) return Node_Id;
181 -- Comparisons between arrays are expanded in line. This function produces
182 -- the body of the implementation of (a > b), where a and b are one-
183 -- dimensional arrays of some discrete type. The original node is then
184 -- expanded into the appropriate call to this function. Nod provides the
185 -- Sloc value for the generated code.
187 function Make_Boolean_Array_Op
189 N : Node_Id) return Node_Id;
190 -- Boolean operations on boolean arrays are expanded in line. This function
191 -- produce the body for the node N, which is (a and b), (a or b), or (a xor
192 -- b). It is used only the normal case and not the packed case. The type
193 -- involved, Typ, is the Boolean array type, and the logical operations in
194 -- the body are simple boolean operations. Note that Typ is always a
195 -- constrained type (the caller has ensured this by using
196 -- Convert_To_Actual_Subtype if necessary).
198 procedure Rewrite_Comparison (N : Node_Id);
199 -- If N is the node for a comparison whose outcome can be determined at
200 -- compile time, then the node N can be rewritten with True or False. If
201 -- the outcome cannot be determined at compile time, the call has no
202 -- effect. If N is a type conversion, then this processing is applied to
203 -- its expression. If N is neither comparison nor a type conversion, the
204 -- call has no effect.
206 function Tagged_Membership (N : Node_Id) return Node_Id;
207 -- Construct the expression corresponding to the tagged membership test.
208 -- Deals with a second operand being (or not) a class-wide type.
210 function Safe_In_Place_Array_Op
213 Op2 : Node_Id) return Boolean;
214 -- In the context of an assignment, where the right-hand side is a boolean
215 -- operation on arrays, check whether operation can be performed in place.
217 procedure Unary_Op_Validity_Checks (N : Node_Id);
218 pragma Inline (Unary_Op_Validity_Checks);
219 -- Performs validity checks for a unary operator
221 -------------------------------
222 -- Binary_Op_Validity_Checks --
223 -------------------------------
225 procedure Binary_Op_Validity_Checks (N : Node_Id) is
227 if Validity_Checks_On and Validity_Check_Operands then
228 Ensure_Valid (Left_Opnd (N));
229 Ensure_Valid (Right_Opnd (N));
231 end Binary_Op_Validity_Checks;
233 ------------------------------------
234 -- Build_Boolean_Array_Proc_Call --
235 ------------------------------------
237 procedure Build_Boolean_Array_Proc_Call
242 Loc : constant Source_Ptr := Sloc (N);
243 Kind : constant Node_Kind := Nkind (Expression (N));
244 Target : constant Node_Id :=
245 Make_Attribute_Reference (Loc,
247 Attribute_Name => Name_Address);
249 Arg1 : constant Node_Id := Op1;
250 Arg2 : Node_Id := Op2;
252 Proc_Name : Entity_Id;
255 if Kind = N_Op_Not then
256 if Nkind (Op1) in N_Binary_Op then
258 -- Use negated version of the binary operators
260 if Nkind (Op1) = N_Op_And then
261 Proc_Name := RTE (RE_Vector_Nand);
263 elsif Nkind (Op1) = N_Op_Or then
264 Proc_Name := RTE (RE_Vector_Nor);
266 else pragma Assert (Nkind (Op1) = N_Op_Xor);
267 Proc_Name := RTE (RE_Vector_Xor);
271 Make_Procedure_Call_Statement (Loc,
272 Name => New_Occurrence_Of (Proc_Name, Loc),
274 Parameter_Associations => New_List (
276 Make_Attribute_Reference (Loc,
277 Prefix => Left_Opnd (Op1),
278 Attribute_Name => Name_Address),
280 Make_Attribute_Reference (Loc,
281 Prefix => Right_Opnd (Op1),
282 Attribute_Name => Name_Address),
284 Make_Attribute_Reference (Loc,
285 Prefix => Left_Opnd (Op1),
286 Attribute_Name => Name_Length)));
289 Proc_Name := RTE (RE_Vector_Not);
292 Make_Procedure_Call_Statement (Loc,
293 Name => New_Occurrence_Of (Proc_Name, Loc),
294 Parameter_Associations => New_List (
297 Make_Attribute_Reference (Loc,
299 Attribute_Name => Name_Address),
301 Make_Attribute_Reference (Loc,
303 Attribute_Name => Name_Length)));
307 -- We use the following equivalences:
309 -- (not X) or (not Y) = not (X and Y) = Nand (X, Y)
310 -- (not X) and (not Y) = not (X or Y) = Nor (X, Y)
311 -- (not X) xor (not Y) = X xor Y
312 -- X xor (not Y) = not (X xor Y) = Nxor (X, Y)
314 if Nkind (Op1) = N_Op_Not then
315 if Kind = N_Op_And then
316 Proc_Name := RTE (RE_Vector_Nor);
318 elsif Kind = N_Op_Or then
319 Proc_Name := RTE (RE_Vector_Nand);
322 Proc_Name := RTE (RE_Vector_Xor);
326 if Kind = N_Op_And then
327 Proc_Name := RTE (RE_Vector_And);
329 elsif Kind = N_Op_Or then
330 Proc_Name := RTE (RE_Vector_Or);
332 elsif Nkind (Op2) = N_Op_Not then
333 Proc_Name := RTE (RE_Vector_Nxor);
334 Arg2 := Right_Opnd (Op2);
337 Proc_Name := RTE (RE_Vector_Xor);
342 Make_Procedure_Call_Statement (Loc,
343 Name => New_Occurrence_Of (Proc_Name, Loc),
344 Parameter_Associations => New_List (
346 Make_Attribute_Reference (Loc,
348 Attribute_Name => Name_Address),
349 Make_Attribute_Reference (Loc,
351 Attribute_Name => Name_Address),
352 Make_Attribute_Reference (Loc,
354 Attribute_Name => Name_Length)));
357 Rewrite (N, Call_Node);
361 when RE_Not_Available =>
363 end Build_Boolean_Array_Proc_Call;
365 --------------------------------
366 -- Displace_Allocator_Pointer --
367 --------------------------------
369 procedure Displace_Allocator_Pointer (N : Node_Id) is
370 Loc : constant Source_Ptr := Sloc (N);
371 Orig_Node : constant Node_Id := Original_Node (N);
377 -- Do nothing in case of VM targets: the virtual machine will handle
378 -- interfaces directly.
380 if VM_Target /= No_VM then
384 pragma Assert (Nkind (N) = N_Identifier
385 and then Nkind (Orig_Node) = N_Allocator);
387 PtrT := Etype (Orig_Node);
388 Dtyp := Designated_Type (PtrT);
389 Etyp := Etype (Expression (Orig_Node));
391 if Is_Class_Wide_Type (Dtyp)
392 and then Is_Interface (Dtyp)
394 -- If the type of the allocator expression is not an interface type
395 -- we can generate code to reference the record component containing
396 -- the pointer to the secondary dispatch table.
398 if not Is_Interface (Etyp) then
400 Saved_Typ : constant Entity_Id := Etype (Orig_Node);
403 -- 1) Get access to the allocated object
406 Make_Explicit_Dereference (Loc,
411 -- 2) Add the conversion to displace the pointer to reference
412 -- the secondary dispatch table.
414 Rewrite (N, Convert_To (Dtyp, Relocate_Node (N)));
415 Analyze_And_Resolve (N, Dtyp);
417 -- 3) The 'access to the secondary dispatch table will be used
418 -- as the value returned by the allocator.
421 Make_Attribute_Reference (Loc,
422 Prefix => Relocate_Node (N),
423 Attribute_Name => Name_Access));
424 Set_Etype (N, Saved_Typ);
428 -- If the type of the allocator expression is an interface type we
429 -- generate a run-time call to displace "this" to reference the
430 -- component containing the pointer to the secondary dispatch table
431 -- or else raise Constraint_Error if the actual object does not
432 -- implement the target interface. This case corresponds with the
433 -- following example:
435 -- function Op (Obj : Iface_1'Class) return access Iface_2'Class is
437 -- return new Iface_2'Class'(Obj);
442 Unchecked_Convert_To (PtrT,
443 Make_Function_Call (Loc,
444 Name => New_Reference_To (RTE (RE_Displace), Loc),
445 Parameter_Associations => New_List (
446 Unchecked_Convert_To (RTE (RE_Address),
452 (Access_Disp_Table (Etype (Base_Type (Dtyp))))),
454 Analyze_And_Resolve (N, PtrT);
457 end Displace_Allocator_Pointer;
459 ---------------------------------
460 -- Expand_Allocator_Expression --
461 ---------------------------------
463 procedure Expand_Allocator_Expression (N : Node_Id) is
464 Loc : constant Source_Ptr := Sloc (N);
465 Exp : constant Node_Id := Expression (Expression (N));
466 PtrT : constant Entity_Id := Etype (N);
467 DesigT : constant Entity_Id := Designated_Type (PtrT);
469 procedure Apply_Accessibility_Check
471 Built_In_Place : Boolean := False);
472 -- Ada 2005 (AI-344): For an allocator with a class-wide designated
473 -- type, generate an accessibility check to verify that the level of the
474 -- type of the created object is not deeper than the level of the access
475 -- type. If the type of the qualified expression is class- wide, then
476 -- always generate the check (except in the case where it is known to be
477 -- unnecessary, see comment below). Otherwise, only generate the check
478 -- if the level of the qualified expression type is statically deeper
479 -- than the access type.
481 -- Although the static accessibility will generally have been performed
482 -- as a legality check, it won't have been done in cases where the
483 -- allocator appears in generic body, so a run-time check is needed in
484 -- general. One special case is when the access type is declared in the
485 -- same scope as the class-wide allocator, in which case the check can
486 -- never fail, so it need not be generated.
488 -- As an open issue, there seem to be cases where the static level
489 -- associated with the class-wide object's underlying type is not
490 -- sufficient to perform the proper accessibility check, such as for
491 -- allocators in nested subprograms or accept statements initialized by
492 -- class-wide formals when the actual originates outside at a deeper
493 -- static level. The nested subprogram case might require passing
494 -- accessibility levels along with class-wide parameters, and the task
495 -- case seems to be an actual gap in the language rules that needs to
496 -- be fixed by the ARG. ???
498 -------------------------------
499 -- Apply_Accessibility_Check --
500 -------------------------------
502 procedure Apply_Accessibility_Check
504 Built_In_Place : Boolean := False)
509 -- Note: we skip the accessibility check for the VM case, since
510 -- there does not seem to be any practical way of implementing it.
512 if Ada_Version >= Ada_05
513 and then VM_Target = No_VM
514 and then Is_Class_Wide_Type (DesigT)
515 and then not Scope_Suppress (Accessibility_Check)
517 (Type_Access_Level (Etype (Exp)) > Type_Access_Level (PtrT)
519 (Is_Class_Wide_Type (Etype (Exp))
520 and then Scope (PtrT) /= Current_Scope))
522 -- If the allocator was built in place Ref is already a reference
523 -- to the access object initialized to the result of the allocator
524 -- (see Exp_Ch6.Make_Build_In_Place_Call_In_Allocator). Otherwise
525 -- it is the entity associated with the object containing the
526 -- address of the allocated object.
528 if Built_In_Place then
529 Ref_Node := New_Copy (Ref);
531 Ref_Node := New_Reference_To (Ref, Loc);
535 Make_Raise_Program_Error (Loc,
539 Build_Get_Access_Level (Loc,
540 Make_Attribute_Reference (Loc,
542 Attribute_Name => Name_Tag)),
544 Make_Integer_Literal (Loc,
545 Type_Access_Level (PtrT))),
546 Reason => PE_Accessibility_Check_Failed));
548 end Apply_Accessibility_Check;
552 Indic : constant Node_Id := Subtype_Mark (Expression (N));
553 T : constant Entity_Id := Entity (Indic);
558 TagT : Entity_Id := Empty;
559 -- Type used as source for tag assignment
561 TagR : Node_Id := Empty;
562 -- Target reference for tag assignment
564 Aggr_In_Place : constant Boolean := Is_Delayed_Aggregate (Exp);
566 Tag_Assign : Node_Id;
569 -- Start of processing for Expand_Allocator_Expression
572 if Is_Tagged_Type (T) or else Needs_Finalization (T) then
574 -- Ada 2005 (AI-318-02): If the initialization expression is a call
575 -- to a build-in-place function, then access to the allocated object
576 -- must be passed to the function. Currently we limit such functions
577 -- to those with constrained limited result subtypes, but eventually
578 -- we plan to expand the allowed forms of functions that are treated
579 -- as build-in-place.
581 if Ada_Version >= Ada_05
582 and then Is_Build_In_Place_Function_Call (Exp)
584 Make_Build_In_Place_Call_In_Allocator (N, Exp);
585 Apply_Accessibility_Check (N, Built_In_Place => True);
589 -- Actions inserted before:
590 -- Temp : constant ptr_T := new T'(Expression);
591 -- <no CW> Temp._tag := T'tag;
592 -- <CTRL> Adjust (Finalizable (Temp.all));
593 -- <CTRL> Attach_To_Final_List (Finalizable (Temp.all));
595 -- We analyze by hand the new internal allocator to avoid
596 -- any recursion and inappropriate call to Initialize
598 -- We don't want to remove side effects when the expression must be
599 -- built in place. In the case of a build-in-place function call,
600 -- that could lead to a duplication of the call, which was already
601 -- substituted for the allocator.
603 if not Aggr_In_Place then
604 Remove_Side_Effects (Exp);
608 Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
610 -- For a class wide allocation generate the following code:
612 -- type Equiv_Record is record ... end record;
613 -- implicit subtype CW is <Class_Wide_Subytpe>;
614 -- temp : PtrT := new CW'(CW!(expr));
616 if Is_Class_Wide_Type (T) then
617 Expand_Subtype_From_Expr (Empty, T, Indic, Exp);
619 -- Ada 2005 (AI-251): If the expression is a class-wide interface
620 -- object we generate code to move up "this" to reference the
621 -- base of the object before allocating the new object.
623 -- Note that Exp'Address is recursively expanded into a call
624 -- to Base_Address (Exp.Tag)
626 if Is_Class_Wide_Type (Etype (Exp))
627 and then Is_Interface (Etype (Exp))
628 and then VM_Target = No_VM
632 Unchecked_Convert_To (Entity (Indic),
633 Make_Explicit_Dereference (Loc,
634 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
635 Make_Attribute_Reference (Loc,
637 Attribute_Name => Name_Address)))));
642 Unchecked_Convert_To (Entity (Indic), Exp));
645 Analyze_And_Resolve (Expression (N), Entity (Indic));
648 -- Keep separate the management of allocators returning interfaces
650 if not Is_Interface (Directly_Designated_Type (PtrT)) then
651 if Aggr_In_Place then
653 Make_Object_Declaration (Loc,
654 Defining_Identifier => Temp,
655 Object_Definition => New_Reference_To (PtrT, Loc),
658 New_Reference_To (Etype (Exp), Loc)));
660 -- Copy the Comes_From_Source flag for the allocator we just
661 -- built, since logically this allocator is a replacement of
662 -- the original allocator node. This is for proper handling of
663 -- restriction No_Implicit_Heap_Allocations.
665 Set_Comes_From_Source
666 (Expression (Tmp_Node), Comes_From_Source (N));
668 Set_No_Initialization (Expression (Tmp_Node));
669 Insert_Action (N, Tmp_Node);
671 if Needs_Finalization (T)
672 and then Ekind (PtrT) = E_Anonymous_Access_Type
674 -- Create local finalization list for access parameter
676 Flist := Get_Allocator_Final_List (N, Base_Type (T), PtrT);
679 Convert_Aggr_In_Allocator (N, Tmp_Node, Exp);
682 Node := Relocate_Node (N);
685 Make_Object_Declaration (Loc,
686 Defining_Identifier => Temp,
687 Constant_Present => True,
688 Object_Definition => New_Reference_To (PtrT, Loc),
689 Expression => Node));
692 -- Ada 2005 (AI-251): Handle allocators whose designated type is an
693 -- interface type. In this case we use the type of the qualified
694 -- expression to allocate the object.
698 Def_Id : constant Entity_Id :=
699 Make_Defining_Identifier (Loc,
700 New_Internal_Name ('T'));
705 Make_Full_Type_Declaration (Loc,
706 Defining_Identifier => Def_Id,
708 Make_Access_To_Object_Definition (Loc,
710 Null_Exclusion_Present => False,
711 Constant_Present => False,
712 Subtype_Indication =>
713 New_Reference_To (Etype (Exp), Loc)));
715 Insert_Action (N, New_Decl);
717 -- Inherit the final chain to ensure that the expansion of the
718 -- aggregate is correct in case of controlled types
720 if Needs_Finalization (Directly_Designated_Type (PtrT)) then
721 Set_Associated_Final_Chain (Def_Id,
722 Associated_Final_Chain (PtrT));
725 -- Declare the object using the previous type declaration
727 if Aggr_In_Place then
729 Make_Object_Declaration (Loc,
730 Defining_Identifier => Temp,
731 Object_Definition => New_Reference_To (Def_Id, Loc),
734 New_Reference_To (Etype (Exp), Loc)));
736 -- Copy the Comes_From_Source flag for the allocator we just
737 -- built, since logically this allocator is a replacement of
738 -- the original allocator node. This is for proper handling
739 -- of restriction No_Implicit_Heap_Allocations.
741 Set_Comes_From_Source
742 (Expression (Tmp_Node), Comes_From_Source (N));
744 Set_No_Initialization (Expression (Tmp_Node));
745 Insert_Action (N, Tmp_Node);
747 if Needs_Finalization (T)
748 and then Ekind (PtrT) = E_Anonymous_Access_Type
750 -- Create local finalization list for access parameter
753 Get_Allocator_Final_List (N, Base_Type (T), PtrT);
756 Convert_Aggr_In_Allocator (N, Tmp_Node, Exp);
758 Node := Relocate_Node (N);
761 Make_Object_Declaration (Loc,
762 Defining_Identifier => Temp,
763 Constant_Present => True,
764 Object_Definition => New_Reference_To (Def_Id, Loc),
765 Expression => Node));
768 -- Generate an additional object containing the address of the
769 -- returned object. The type of this second object declaration
770 -- is the correct type required for the common processing that
771 -- is still performed by this subprogram. The displacement of
772 -- this pointer to reference the component associated with the
773 -- interface type will be done at the end of common processing.
776 Make_Object_Declaration (Loc,
777 Defining_Identifier => Make_Defining_Identifier (Loc,
778 New_Internal_Name ('P')),
779 Object_Definition => New_Reference_To (PtrT, Loc),
780 Expression => Unchecked_Convert_To (PtrT,
781 New_Reference_To (Temp, Loc)));
783 Insert_Action (N, New_Decl);
785 Tmp_Node := New_Decl;
786 Temp := Defining_Identifier (New_Decl);
790 Apply_Accessibility_Check (Temp);
792 -- Generate the tag assignment
794 -- Suppress the tag assignment when VM_Target because VM tags are
795 -- represented implicitly in objects.
797 if VM_Target /= No_VM then
800 -- Ada 2005 (AI-251): Suppress the tag assignment with class-wide
801 -- interface objects because in this case the tag does not change.
803 elsif Is_Interface (Directly_Designated_Type (Etype (N))) then
804 pragma Assert (Is_Class_Wide_Type
805 (Directly_Designated_Type (Etype (N))));
808 elsif Is_Tagged_Type (T) and then not Is_Class_Wide_Type (T) then
810 TagR := New_Reference_To (Temp, Loc);
812 elsif Is_Private_Type (T)
813 and then Is_Tagged_Type (Underlying_Type (T))
815 TagT := Underlying_Type (T);
817 Unchecked_Convert_To (Underlying_Type (T),
818 Make_Explicit_Dereference (Loc,
819 Prefix => New_Reference_To (Temp, Loc)));
822 if Present (TagT) then
824 Make_Assignment_Statement (Loc,
826 Make_Selected_Component (Loc,
829 New_Reference_To (First_Tag_Component (TagT), Loc)),
832 Unchecked_Convert_To (RTE (RE_Tag),
834 (Elists.Node (First_Elmt (Access_Disp_Table (TagT))),
837 -- The previous assignment has to be done in any case
839 Set_Assignment_OK (Name (Tag_Assign));
840 Insert_Action (N, Tag_Assign);
843 if Needs_Finalization (DesigT)
844 and then Needs_Finalization (T)
848 Apool : constant Entity_Id :=
849 Associated_Storage_Pool (PtrT);
852 -- If it is an allocation on the secondary stack (i.e. a value
853 -- returned from a function), the object is attached on the
854 -- caller side as soon as the call is completed (see
855 -- Expand_Ctrl_Function_Call)
857 if Is_RTE (Apool, RE_SS_Pool) then
859 F : constant Entity_Id :=
860 Make_Defining_Identifier (Loc,
861 New_Internal_Name ('F'));
864 Make_Object_Declaration (Loc,
865 Defining_Identifier => F,
866 Object_Definition => New_Reference_To (RTE
867 (RE_Finalizable_Ptr), Loc)));
869 Flist := New_Reference_To (F, Loc);
870 Attach := Make_Integer_Literal (Loc, 1);
873 -- Normal case, not a secondary stack allocation
876 if Needs_Finalization (T)
877 and then Ekind (PtrT) = E_Anonymous_Access_Type
879 -- Create local finalization list for access parameter
882 Get_Allocator_Final_List (N, Base_Type (T), PtrT);
884 Flist := Find_Final_List (PtrT);
887 Attach := Make_Integer_Literal (Loc, 2);
890 -- Generate an Adjust call if the object will be moved. In Ada
891 -- 2005, the object may be inherently limited, in which case
892 -- there is no Adjust procedure, and the object is built in
893 -- place. In Ada 95, the object can be limited but not
894 -- inherently limited if this allocator came from a return
895 -- statement (we're allocating the result on the secondary
896 -- stack). In that case, the object will be moved, so we _do_
900 and then not Is_Inherently_Limited_Type (T)
906 -- An unchecked conversion is needed in the classwide
907 -- case because the designated type can be an ancestor of
908 -- the subtype mark of the allocator.
910 Unchecked_Convert_To (T,
911 Make_Explicit_Dereference (Loc,
912 Prefix => New_Reference_To (Temp, Loc))),
916 With_Attach => Attach,
922 Rewrite (N, New_Reference_To (Temp, Loc));
923 Analyze_And_Resolve (N, PtrT);
925 -- Ada 2005 (AI-251): Displace the pointer to reference the record
926 -- component containing the secondary dispatch table of the interface
929 if Is_Interface (Directly_Designated_Type (PtrT)) then
930 Displace_Allocator_Pointer (N);
933 elsif Aggr_In_Place then
935 Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
937 Make_Object_Declaration (Loc,
938 Defining_Identifier => Temp,
939 Object_Definition => New_Reference_To (PtrT, Loc),
940 Expression => Make_Allocator (Loc,
941 New_Reference_To (Etype (Exp), Loc)));
943 -- Copy the Comes_From_Source flag for the allocator we just built,
944 -- since logically this allocator is a replacement of the original
945 -- allocator node. This is for proper handling of restriction
946 -- No_Implicit_Heap_Allocations.
948 Set_Comes_From_Source
949 (Expression (Tmp_Node), Comes_From_Source (N));
951 Set_No_Initialization (Expression (Tmp_Node));
952 Insert_Action (N, Tmp_Node);
953 Convert_Aggr_In_Allocator (N, Tmp_Node, Exp);
954 Rewrite (N, New_Reference_To (Temp, Loc));
955 Analyze_And_Resolve (N, PtrT);
957 elsif Is_Access_Type (T)
958 and then Can_Never_Be_Null (T)
960 Install_Null_Excluding_Check (Exp);
962 elsif Is_Access_Type (DesigT)
963 and then Nkind (Exp) = N_Allocator
964 and then Nkind (Expression (Exp)) /= N_Qualified_Expression
966 -- Apply constraint to designated subtype indication
968 Apply_Constraint_Check (Expression (Exp),
969 Designated_Type (DesigT),
972 if Nkind (Expression (Exp)) = N_Raise_Constraint_Error then
974 -- Propagate constraint_error to enclosing allocator
976 Rewrite (Exp, New_Copy (Expression (Exp)));
979 -- First check against the type of the qualified expression
981 -- NOTE: The commented call should be correct, but for some reason
982 -- causes the compiler to bomb (sigsegv) on ACVC test c34007g, so for
983 -- now we just perform the old (incorrect) test against the
984 -- designated subtype with no sliding in the else part of the if
985 -- statement below. ???
987 -- Apply_Constraint_Check (Exp, T, No_Sliding => True);
989 -- A check is also needed in cases where the designated subtype is
990 -- constrained and differs from the subtype given in the qualified
991 -- expression. Note that the check on the qualified expression does
992 -- not allow sliding, but this check does (a relaxation from Ada 83).
994 if Is_Constrained (DesigT)
995 and then not Subtypes_Statically_Match (T, DesigT)
997 Apply_Constraint_Check
998 (Exp, DesigT, No_Sliding => False);
1000 -- The nonsliding check should really be performed (unconditionally)
1001 -- against the subtype of the qualified expression, but that causes a
1002 -- problem with c34007g (see above), so for now we retain this.
1005 Apply_Constraint_Check
1006 (Exp, DesigT, No_Sliding => True);
1009 -- For an access to unconstrained packed array, GIGI needs to see an
1010 -- expression with a constrained subtype in order to compute the
1011 -- proper size for the allocator.
1013 if Is_Array_Type (T)
1014 and then not Is_Constrained (T)
1015 and then Is_Packed (T)
1018 ConstrT : constant Entity_Id :=
1019 Make_Defining_Identifier (Loc,
1020 Chars => New_Internal_Name ('A'));
1021 Internal_Exp : constant Node_Id := Relocate_Node (Exp);
1024 Make_Subtype_Declaration (Loc,
1025 Defining_Identifier => ConstrT,
1026 Subtype_Indication =>
1027 Make_Subtype_From_Expr (Exp, T)));
1028 Freeze_Itype (ConstrT, Exp);
1029 Rewrite (Exp, OK_Convert_To (ConstrT, Internal_Exp));
1033 -- Ada 2005 (AI-318-02): If the initialization expression is a call
1034 -- to a build-in-place function, then access to the allocated object
1035 -- must be passed to the function. Currently we limit such functions
1036 -- to those with constrained limited result subtypes, but eventually
1037 -- we plan to expand the allowed forms of functions that are treated
1038 -- as build-in-place.
1040 if Ada_Version >= Ada_05
1041 and then Is_Build_In_Place_Function_Call (Exp)
1043 Make_Build_In_Place_Call_In_Allocator (N, Exp);
1048 when RE_Not_Available =>
1050 end Expand_Allocator_Expression;
1052 -----------------------------
1053 -- Expand_Array_Comparison --
1054 -----------------------------
1056 -- Expansion is only required in the case of array types. For the unpacked
1057 -- case, an appropriate runtime routine is called. For packed cases, and
1058 -- also in some other cases where a runtime routine cannot be called, the
1059 -- form of the expansion is:
1061 -- [body for greater_nn; boolean_expression]
1063 -- The body is built by Make_Array_Comparison_Op, and the form of the
1064 -- Boolean expression depends on the operator involved.
1066 procedure Expand_Array_Comparison (N : Node_Id) is
1067 Loc : constant Source_Ptr := Sloc (N);
1068 Op1 : Node_Id := Left_Opnd (N);
1069 Op2 : Node_Id := Right_Opnd (N);
1070 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
1071 Ctyp : constant Entity_Id := Component_Type (Typ1);
1074 Func_Body : Node_Id;
1075 Func_Name : Entity_Id;
1079 Byte_Addressable : constant Boolean := System_Storage_Unit = Byte'Size;
1080 -- True for byte addressable target
1082 function Length_Less_Than_4 (Opnd : Node_Id) return Boolean;
1083 -- Returns True if the length of the given operand is known to be less
1084 -- than 4. Returns False if this length is known to be four or greater
1085 -- or is not known at compile time.
1087 ------------------------
1088 -- Length_Less_Than_4 --
1089 ------------------------
1091 function Length_Less_Than_4 (Opnd : Node_Id) return Boolean is
1092 Otyp : constant Entity_Id := Etype (Opnd);
1095 if Ekind (Otyp) = E_String_Literal_Subtype then
1096 return String_Literal_Length (Otyp) < 4;
1100 Ityp : constant Entity_Id := Etype (First_Index (Otyp));
1101 Lo : constant Node_Id := Type_Low_Bound (Ityp);
1102 Hi : constant Node_Id := Type_High_Bound (Ityp);
1107 if Compile_Time_Known_Value (Lo) then
1108 Lov := Expr_Value (Lo);
1113 if Compile_Time_Known_Value (Hi) then
1114 Hiv := Expr_Value (Hi);
1119 return Hiv < Lov + 3;
1122 end Length_Less_Than_4;
1124 -- Start of processing for Expand_Array_Comparison
1127 -- Deal first with unpacked case, where we can call a runtime routine
1128 -- except that we avoid this for targets for which are not addressable
1129 -- by bytes, and for the JVM/CIL, since they do not support direct
1130 -- addressing of array components.
1132 if not Is_Bit_Packed_Array (Typ1)
1133 and then Byte_Addressable
1134 and then VM_Target = No_VM
1136 -- The call we generate is:
1138 -- Compare_Array_xn[_Unaligned]
1139 -- (left'address, right'address, left'length, right'length) <op> 0
1141 -- x = U for unsigned, S for signed
1142 -- n = 8,16,32,64 for component size
1143 -- Add _Unaligned if length < 4 and component size is 8.
1144 -- <op> is the standard comparison operator
1146 if Component_Size (Typ1) = 8 then
1147 if Length_Less_Than_4 (Op1)
1149 Length_Less_Than_4 (Op2)
1151 if Is_Unsigned_Type (Ctyp) then
1152 Comp := RE_Compare_Array_U8_Unaligned;
1154 Comp := RE_Compare_Array_S8_Unaligned;
1158 if Is_Unsigned_Type (Ctyp) then
1159 Comp := RE_Compare_Array_U8;
1161 Comp := RE_Compare_Array_S8;
1165 elsif Component_Size (Typ1) = 16 then
1166 if Is_Unsigned_Type (Ctyp) then
1167 Comp := RE_Compare_Array_U16;
1169 Comp := RE_Compare_Array_S16;
1172 elsif Component_Size (Typ1) = 32 then
1173 if Is_Unsigned_Type (Ctyp) then
1174 Comp := RE_Compare_Array_U32;
1176 Comp := RE_Compare_Array_S32;
1179 else pragma Assert (Component_Size (Typ1) = 64);
1180 if Is_Unsigned_Type (Ctyp) then
1181 Comp := RE_Compare_Array_U64;
1183 Comp := RE_Compare_Array_S64;
1187 Remove_Side_Effects (Op1, Name_Req => True);
1188 Remove_Side_Effects (Op2, Name_Req => True);
1191 Make_Function_Call (Sloc (Op1),
1192 Name => New_Occurrence_Of (RTE (Comp), Loc),
1194 Parameter_Associations => New_List (
1195 Make_Attribute_Reference (Loc,
1196 Prefix => Relocate_Node (Op1),
1197 Attribute_Name => Name_Address),
1199 Make_Attribute_Reference (Loc,
1200 Prefix => Relocate_Node (Op2),
1201 Attribute_Name => Name_Address),
1203 Make_Attribute_Reference (Loc,
1204 Prefix => Relocate_Node (Op1),
1205 Attribute_Name => Name_Length),
1207 Make_Attribute_Reference (Loc,
1208 Prefix => Relocate_Node (Op2),
1209 Attribute_Name => Name_Length))));
1212 Make_Integer_Literal (Sloc (Op2),
1215 Analyze_And_Resolve (Op1, Standard_Integer);
1216 Analyze_And_Resolve (Op2, Standard_Integer);
1220 -- Cases where we cannot make runtime call
1222 -- For (a <= b) we convert to not (a > b)
1224 if Chars (N) = Name_Op_Le then
1230 Right_Opnd => Op2)));
1231 Analyze_And_Resolve (N, Standard_Boolean);
1234 -- For < the Boolean expression is
1235 -- greater__nn (op2, op1)
1237 elsif Chars (N) = Name_Op_Lt then
1238 Func_Body := Make_Array_Comparison_Op (Typ1, N);
1242 Op1 := Right_Opnd (N);
1243 Op2 := Left_Opnd (N);
1245 -- For (a >= b) we convert to not (a < b)
1247 elsif Chars (N) = Name_Op_Ge then
1253 Right_Opnd => Op2)));
1254 Analyze_And_Resolve (N, Standard_Boolean);
1257 -- For > the Boolean expression is
1258 -- greater__nn (op1, op2)
1261 pragma Assert (Chars (N) = Name_Op_Gt);
1262 Func_Body := Make_Array_Comparison_Op (Typ1, N);
1265 Func_Name := Defining_Unit_Name (Specification (Func_Body));
1267 Make_Function_Call (Loc,
1268 Name => New_Reference_To (Func_Name, Loc),
1269 Parameter_Associations => New_List (Op1, Op2));
1271 Insert_Action (N, Func_Body);
1273 Analyze_And_Resolve (N, Standard_Boolean);
1276 when RE_Not_Available =>
1278 end Expand_Array_Comparison;
1280 ---------------------------
1281 -- Expand_Array_Equality --
1282 ---------------------------
1284 -- Expand an equality function for multi-dimensional arrays. Here is an
1285 -- example of such a function for Nb_Dimension = 2
1287 -- function Enn (A : atyp; B : btyp) return boolean is
1289 -- if (A'length (1) = 0 or else A'length (2) = 0)
1291 -- (B'length (1) = 0 or else B'length (2) = 0)
1293 -- return True; -- RM 4.5.2(22)
1296 -- if A'length (1) /= B'length (1)
1298 -- A'length (2) /= B'length (2)
1300 -- return False; -- RM 4.5.2(23)
1304 -- A1 : Index_T1 := A'first (1);
1305 -- B1 : Index_T1 := B'first (1);
1309 -- A2 : Index_T2 := A'first (2);
1310 -- B2 : Index_T2 := B'first (2);
1313 -- if A (A1, A2) /= B (B1, B2) then
1317 -- exit when A2 = A'last (2);
1318 -- A2 := Index_T2'succ (A2);
1319 -- B2 := Index_T2'succ (B2);
1323 -- exit when A1 = A'last (1);
1324 -- A1 := Index_T1'succ (A1);
1325 -- B1 := Index_T1'succ (B1);
1332 -- Note on the formal types used (atyp and btyp). If either of the arrays
1333 -- is of a private type, we use the underlying type, and do an unchecked
1334 -- conversion of the actual. If either of the arrays has a bound depending
1335 -- on a discriminant, then we use the base type since otherwise we have an
1336 -- escaped discriminant in the function.
1338 -- If both arrays are constrained and have the same bounds, we can generate
1339 -- a loop with an explicit iteration scheme using a 'Range attribute over
1342 function Expand_Array_Equality
1347 Typ : Entity_Id) return Node_Id
1349 Loc : constant Source_Ptr := Sloc (Nod);
1350 Decls : constant List_Id := New_List;
1351 Index_List1 : constant List_Id := New_List;
1352 Index_List2 : constant List_Id := New_List;
1356 Func_Name : Entity_Id;
1357 Func_Body : Node_Id;
1359 A : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uA);
1360 B : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uB);
1364 -- The parameter types to be used for the formals
1369 Num : Int) return Node_Id;
1370 -- This builds the attribute reference Arr'Nam (Expr)
1372 function Component_Equality (Typ : Entity_Id) return Node_Id;
1373 -- Create one statement to compare corresponding components, designated
1374 -- by a full set of indices.
1376 function Get_Arg_Type (N : Node_Id) return Entity_Id;
1377 -- Given one of the arguments, computes the appropriate type to be used
1378 -- for that argument in the corresponding function formal
1380 function Handle_One_Dimension
1382 Index : Node_Id) return Node_Id;
1383 -- This procedure returns the following code
1386 -- Bn : Index_T := B'First (N);
1390 -- exit when An = A'Last (N);
1391 -- An := Index_T'Succ (An)
1392 -- Bn := Index_T'Succ (Bn)
1396 -- If both indices are constrained and identical, the procedure
1397 -- returns a simpler loop:
1399 -- for An in A'Range (N) loop
1403 -- N is the dimension for which we are generating a loop. Index is the
1404 -- N'th index node, whose Etype is Index_Type_n in the above code. The
1405 -- xxx statement is either the loop or declare for the next dimension
1406 -- or if this is the last dimension the comparison of corresponding
1407 -- components of the arrays.
1409 -- The actual way the code works is to return the comparison of
1410 -- corresponding components for the N+1 call. That's neater!
1412 function Test_Empty_Arrays return Node_Id;
1413 -- This function constructs the test for both arrays being empty
1414 -- (A'length (1) = 0 or else A'length (2) = 0 or else ...)
1416 -- (B'length (1) = 0 or else B'length (2) = 0 or else ...)
1418 function Test_Lengths_Correspond return Node_Id;
1419 -- This function constructs the test for arrays having different lengths
1420 -- in at least one index position, in which case the resulting code is:
1422 -- A'length (1) /= B'length (1)
1424 -- A'length (2) /= B'length (2)
1435 Num : Int) return Node_Id
1439 Make_Attribute_Reference (Loc,
1440 Attribute_Name => Nam,
1441 Prefix => New_Reference_To (Arr, Loc),
1442 Expressions => New_List (Make_Integer_Literal (Loc, Num)));
1445 ------------------------
1446 -- Component_Equality --
1447 ------------------------
1449 function Component_Equality (Typ : Entity_Id) return Node_Id is
1454 -- if a(i1...) /= b(j1...) then return false; end if;
1457 Make_Indexed_Component (Loc,
1458 Prefix => Make_Identifier (Loc, Chars (A)),
1459 Expressions => Index_List1);
1462 Make_Indexed_Component (Loc,
1463 Prefix => Make_Identifier (Loc, Chars (B)),
1464 Expressions => Index_List2);
1466 Test := Expand_Composite_Equality
1467 (Nod, Component_Type (Typ), L, R, Decls);
1469 -- If some (sub)component is an unchecked_union, the whole operation
1470 -- will raise program error.
1472 if Nkind (Test) = N_Raise_Program_Error then
1474 -- This node is going to be inserted at a location where a
1475 -- statement is expected: clear its Etype so analysis will set
1476 -- it to the expected Standard_Void_Type.
1478 Set_Etype (Test, Empty);
1483 Make_Implicit_If_Statement (Nod,
1484 Condition => Make_Op_Not (Loc, Right_Opnd => Test),
1485 Then_Statements => New_List (
1486 Make_Simple_Return_Statement (Loc,
1487 Expression => New_Occurrence_Of (Standard_False, Loc))));
1489 end Component_Equality;
1495 function Get_Arg_Type (N : Node_Id) return Entity_Id is
1506 T := Underlying_Type (T);
1508 X := First_Index (T);
1509 while Present (X) loop
1510 if Denotes_Discriminant (Type_Low_Bound (Etype (X)))
1512 Denotes_Discriminant (Type_High_Bound (Etype (X)))
1525 --------------------------
1526 -- Handle_One_Dimension --
1527 ---------------------------
1529 function Handle_One_Dimension
1531 Index : Node_Id) return Node_Id
1533 Need_Separate_Indexes : constant Boolean :=
1535 or else not Is_Constrained (Ltyp);
1536 -- If the index types are identical, and we are working with
1537 -- constrained types, then we can use the same index for both
1540 An : constant Entity_Id := Make_Defining_Identifier (Loc,
1541 Chars => New_Internal_Name ('A'));
1544 Index_T : Entity_Id;
1549 if N > Number_Dimensions (Ltyp) then
1550 return Component_Equality (Ltyp);
1553 -- Case where we generate a loop
1555 Index_T := Base_Type (Etype (Index));
1557 if Need_Separate_Indexes then
1559 Make_Defining_Identifier (Loc,
1560 Chars => New_Internal_Name ('B'));
1565 Append (New_Reference_To (An, Loc), Index_List1);
1566 Append (New_Reference_To (Bn, Loc), Index_List2);
1568 Stm_List := New_List (
1569 Handle_One_Dimension (N + 1, Next_Index (Index)));
1571 if Need_Separate_Indexes then
1573 -- Generate guard for loop, followed by increments of indices
1575 Append_To (Stm_List,
1576 Make_Exit_Statement (Loc,
1579 Left_Opnd => New_Reference_To (An, Loc),
1580 Right_Opnd => Arr_Attr (A, Name_Last, N))));
1582 Append_To (Stm_List,
1583 Make_Assignment_Statement (Loc,
1584 Name => New_Reference_To (An, Loc),
1586 Make_Attribute_Reference (Loc,
1587 Prefix => New_Reference_To (Index_T, Loc),
1588 Attribute_Name => Name_Succ,
1589 Expressions => New_List (New_Reference_To (An, Loc)))));
1591 Append_To (Stm_List,
1592 Make_Assignment_Statement (Loc,
1593 Name => New_Reference_To (Bn, Loc),
1595 Make_Attribute_Reference (Loc,
1596 Prefix => New_Reference_To (Index_T, Loc),
1597 Attribute_Name => Name_Succ,
1598 Expressions => New_List (New_Reference_To (Bn, Loc)))));
1601 -- If separate indexes, we need a declare block for An and Bn, and a
1602 -- loop without an iteration scheme.
1604 if Need_Separate_Indexes then
1606 Make_Implicit_Loop_Statement (Nod, Statements => Stm_List);
1609 Make_Block_Statement (Loc,
1610 Declarations => New_List (
1611 Make_Object_Declaration (Loc,
1612 Defining_Identifier => An,
1613 Object_Definition => New_Reference_To (Index_T, Loc),
1614 Expression => Arr_Attr (A, Name_First, N)),
1616 Make_Object_Declaration (Loc,
1617 Defining_Identifier => Bn,
1618 Object_Definition => New_Reference_To (Index_T, Loc),
1619 Expression => Arr_Attr (B, Name_First, N))),
1621 Handled_Statement_Sequence =>
1622 Make_Handled_Sequence_Of_Statements (Loc,
1623 Statements => New_List (Loop_Stm)));
1625 -- If no separate indexes, return loop statement with explicit
1626 -- iteration scheme on its own
1630 Make_Implicit_Loop_Statement (Nod,
1631 Statements => Stm_List,
1633 Make_Iteration_Scheme (Loc,
1634 Loop_Parameter_Specification =>
1635 Make_Loop_Parameter_Specification (Loc,
1636 Defining_Identifier => An,
1637 Discrete_Subtype_Definition =>
1638 Arr_Attr (A, Name_Range, N))));
1641 end Handle_One_Dimension;
1643 -----------------------
1644 -- Test_Empty_Arrays --
1645 -----------------------
1647 function Test_Empty_Arrays return Node_Id is
1657 for J in 1 .. Number_Dimensions (Ltyp) loop
1660 Left_Opnd => Arr_Attr (A, Name_Length, J),
1661 Right_Opnd => Make_Integer_Literal (Loc, 0));
1665 Left_Opnd => Arr_Attr (B, Name_Length, J),
1666 Right_Opnd => Make_Integer_Literal (Loc, 0));
1675 Left_Opnd => Relocate_Node (Alist),
1676 Right_Opnd => Atest);
1680 Left_Opnd => Relocate_Node (Blist),
1681 Right_Opnd => Btest);
1688 Right_Opnd => Blist);
1689 end Test_Empty_Arrays;
1691 -----------------------------
1692 -- Test_Lengths_Correspond --
1693 -----------------------------
1695 function Test_Lengths_Correspond return Node_Id is
1701 for J in 1 .. Number_Dimensions (Ltyp) loop
1704 Left_Opnd => Arr_Attr (A, Name_Length, J),
1705 Right_Opnd => Arr_Attr (B, Name_Length, J));
1712 Left_Opnd => Relocate_Node (Result),
1713 Right_Opnd => Rtest);
1718 end Test_Lengths_Correspond;
1720 -- Start of processing for Expand_Array_Equality
1723 Ltyp := Get_Arg_Type (Lhs);
1724 Rtyp := Get_Arg_Type (Rhs);
1726 -- For now, if the argument types are not the same, go to the base type,
1727 -- since the code assumes that the formals have the same type. This is
1728 -- fixable in future ???
1730 if Ltyp /= Rtyp then
1731 Ltyp := Base_Type (Ltyp);
1732 Rtyp := Base_Type (Rtyp);
1733 pragma Assert (Ltyp = Rtyp);
1736 -- Build list of formals for function
1738 Formals := New_List (
1739 Make_Parameter_Specification (Loc,
1740 Defining_Identifier => A,
1741 Parameter_Type => New_Reference_To (Ltyp, Loc)),
1743 Make_Parameter_Specification (Loc,
1744 Defining_Identifier => B,
1745 Parameter_Type => New_Reference_To (Rtyp, Loc)));
1747 Func_Name := Make_Defining_Identifier (Loc, New_Internal_Name ('E'));
1749 -- Build statement sequence for function
1752 Make_Subprogram_Body (Loc,
1754 Make_Function_Specification (Loc,
1755 Defining_Unit_Name => Func_Name,
1756 Parameter_Specifications => Formals,
1757 Result_Definition => New_Reference_To (Standard_Boolean, Loc)),
1759 Declarations => Decls,
1761 Handled_Statement_Sequence =>
1762 Make_Handled_Sequence_Of_Statements (Loc,
1763 Statements => New_List (
1765 Make_Implicit_If_Statement (Nod,
1766 Condition => Test_Empty_Arrays,
1767 Then_Statements => New_List (
1768 Make_Simple_Return_Statement (Loc,
1770 New_Occurrence_Of (Standard_True, Loc)))),
1772 Make_Implicit_If_Statement (Nod,
1773 Condition => Test_Lengths_Correspond,
1774 Then_Statements => New_List (
1775 Make_Simple_Return_Statement (Loc,
1777 New_Occurrence_Of (Standard_False, Loc)))),
1779 Handle_One_Dimension (1, First_Index (Ltyp)),
1781 Make_Simple_Return_Statement (Loc,
1782 Expression => New_Occurrence_Of (Standard_True, Loc)))));
1784 Set_Has_Completion (Func_Name, True);
1785 Set_Is_Inlined (Func_Name);
1787 -- If the array type is distinct from the type of the arguments, it
1788 -- is the full view of a private type. Apply an unchecked conversion
1789 -- to insure that analysis of the call succeeds.
1799 or else Base_Type (Etype (Lhs)) /= Base_Type (Ltyp)
1801 L := OK_Convert_To (Ltyp, Lhs);
1805 or else Base_Type (Etype (Rhs)) /= Base_Type (Rtyp)
1807 R := OK_Convert_To (Rtyp, Rhs);
1810 Actuals := New_List (L, R);
1813 Append_To (Bodies, Func_Body);
1816 Make_Function_Call (Loc,
1817 Name => New_Reference_To (Func_Name, Loc),
1818 Parameter_Associations => Actuals);
1819 end Expand_Array_Equality;
1821 -----------------------------
1822 -- Expand_Boolean_Operator --
1823 -----------------------------
1825 -- Note that we first get the actual subtypes of the operands, since we
1826 -- always want to deal with types that have bounds.
1828 procedure Expand_Boolean_Operator (N : Node_Id) is
1829 Typ : constant Entity_Id := Etype (N);
1832 -- Special case of bit packed array where both operands are known to be
1833 -- properly aligned. In this case we use an efficient run time routine
1834 -- to carry out the operation (see System.Bit_Ops).
1836 if Is_Bit_Packed_Array (Typ)
1837 and then not Is_Possibly_Unaligned_Object (Left_Opnd (N))
1838 and then not Is_Possibly_Unaligned_Object (Right_Opnd (N))
1840 Expand_Packed_Boolean_Operator (N);
1844 -- For the normal non-packed case, the general expansion is to build
1845 -- function for carrying out the comparison (use Make_Boolean_Array_Op)
1846 -- and then inserting it into the tree. The original operator node is
1847 -- then rewritten as a call to this function. We also use this in the
1848 -- packed case if either operand is a possibly unaligned object.
1851 Loc : constant Source_Ptr := Sloc (N);
1852 L : constant Node_Id := Relocate_Node (Left_Opnd (N));
1853 R : constant Node_Id := Relocate_Node (Right_Opnd (N));
1854 Func_Body : Node_Id;
1855 Func_Name : Entity_Id;
1858 Convert_To_Actual_Subtype (L);
1859 Convert_To_Actual_Subtype (R);
1860 Ensure_Defined (Etype (L), N);
1861 Ensure_Defined (Etype (R), N);
1862 Apply_Length_Check (R, Etype (L));
1864 if Nkind (N) = N_Op_Xor then
1865 Silly_Boolean_Array_Xor_Test (N, Etype (L));
1868 if Nkind (Parent (N)) = N_Assignment_Statement
1869 and then Safe_In_Place_Array_Op (Name (Parent (N)), L, R)
1871 Build_Boolean_Array_Proc_Call (Parent (N), L, R);
1873 elsif Nkind (Parent (N)) = N_Op_Not
1874 and then Nkind (N) = N_Op_And
1876 Safe_In_Place_Array_Op (Name (Parent (Parent (N))), L, R)
1881 Func_Body := Make_Boolean_Array_Op (Etype (L), N);
1882 Func_Name := Defining_Unit_Name (Specification (Func_Body));
1883 Insert_Action (N, Func_Body);
1885 -- Now rewrite the expression with a call
1888 Make_Function_Call (Loc,
1889 Name => New_Reference_To (Func_Name, Loc),
1890 Parameter_Associations =>
1893 Make_Type_Conversion
1894 (Loc, New_Reference_To (Etype (L), Loc), R))));
1896 Analyze_And_Resolve (N, Typ);
1899 end Expand_Boolean_Operator;
1901 -------------------------------
1902 -- Expand_Composite_Equality --
1903 -------------------------------
1905 -- This function is only called for comparing internal fields of composite
1906 -- types when these fields are themselves composites. This is a special
1907 -- case because it is not possible to respect normal Ada visibility rules.
1909 function Expand_Composite_Equality
1914 Bodies : List_Id) return Node_Id
1916 Loc : constant Source_Ptr := Sloc (Nod);
1917 Full_Type : Entity_Id;
1922 if Is_Private_Type (Typ) then
1923 Full_Type := Underlying_Type (Typ);
1928 -- Defense against malformed private types with no completion the error
1929 -- will be diagnosed later by check_completion
1931 if No (Full_Type) then
1932 return New_Reference_To (Standard_False, Loc);
1935 Full_Type := Base_Type (Full_Type);
1937 if Is_Array_Type (Full_Type) then
1939 -- If the operand is an elementary type other than a floating-point
1940 -- type, then we can simply use the built-in block bitwise equality,
1941 -- since the predefined equality operators always apply and bitwise
1942 -- equality is fine for all these cases.
1944 if Is_Elementary_Type (Component_Type (Full_Type))
1945 and then not Is_Floating_Point_Type (Component_Type (Full_Type))
1947 return Make_Op_Eq (Loc, Left_Opnd => Lhs, Right_Opnd => Rhs);
1949 -- For composite component types, and floating-point types, use the
1950 -- expansion. This deals with tagged component types (where we use
1951 -- the applicable equality routine) and floating-point, (where we
1952 -- need to worry about negative zeroes), and also the case of any
1953 -- composite type recursively containing such fields.
1956 return Expand_Array_Equality (Nod, Lhs, Rhs, Bodies, Full_Type);
1959 elsif Is_Tagged_Type (Full_Type) then
1961 -- Call the primitive operation "=" of this type
1963 if Is_Class_Wide_Type (Full_Type) then
1964 Full_Type := Root_Type (Full_Type);
1967 -- If this is derived from an untagged private type completed with a
1968 -- tagged type, it does not have a full view, so we use the primitive
1969 -- operations of the private type. This check should no longer be
1970 -- necessary when these types receive their full views ???
1972 if Is_Private_Type (Typ)
1973 and then not Is_Tagged_Type (Typ)
1974 and then not Is_Controlled (Typ)
1975 and then Is_Derived_Type (Typ)
1976 and then No (Full_View (Typ))
1978 Prim := First_Elmt (Collect_Primitive_Operations (Typ));
1980 Prim := First_Elmt (Primitive_Operations (Full_Type));
1984 Eq_Op := Node (Prim);
1985 exit when Chars (Eq_Op) = Name_Op_Eq
1986 and then Etype (First_Formal (Eq_Op)) =
1987 Etype (Next_Formal (First_Formal (Eq_Op)))
1988 and then Base_Type (Etype (Eq_Op)) = Standard_Boolean;
1990 pragma Assert (Present (Prim));
1993 Eq_Op := Node (Prim);
1996 Make_Function_Call (Loc,
1997 Name => New_Reference_To (Eq_Op, Loc),
1998 Parameter_Associations =>
2000 (Unchecked_Convert_To (Etype (First_Formal (Eq_Op)), Lhs),
2001 Unchecked_Convert_To (Etype (First_Formal (Eq_Op)), Rhs)));
2003 elsif Is_Record_Type (Full_Type) then
2004 Eq_Op := TSS (Full_Type, TSS_Composite_Equality);
2006 if Present (Eq_Op) then
2007 if Etype (First_Formal (Eq_Op)) /= Full_Type then
2009 -- Inherited equality from parent type. Convert the actuals to
2010 -- match signature of operation.
2013 T : constant Entity_Id := Etype (First_Formal (Eq_Op));
2017 Make_Function_Call (Loc,
2018 Name => New_Reference_To (Eq_Op, Loc),
2019 Parameter_Associations =>
2020 New_List (OK_Convert_To (T, Lhs),
2021 OK_Convert_To (T, Rhs)));
2025 -- Comparison between Unchecked_Union components
2027 if Is_Unchecked_Union (Full_Type) then
2029 Lhs_Type : Node_Id := Full_Type;
2030 Rhs_Type : Node_Id := Full_Type;
2031 Lhs_Discr_Val : Node_Id;
2032 Rhs_Discr_Val : Node_Id;
2037 if Nkind (Lhs) = N_Selected_Component then
2038 Lhs_Type := Etype (Entity (Selector_Name (Lhs)));
2043 if Nkind (Rhs) = N_Selected_Component then
2044 Rhs_Type := Etype (Entity (Selector_Name (Rhs)));
2047 -- Lhs of the composite equality
2049 if Is_Constrained (Lhs_Type) then
2051 -- Since the enclosing record type can never be an
2052 -- Unchecked_Union (this code is executed for records
2053 -- that do not have variants), we may reference its
2056 if Nkind (Lhs) = N_Selected_Component
2057 and then Has_Per_Object_Constraint (
2058 Entity (Selector_Name (Lhs)))
2061 Make_Selected_Component (Loc,
2062 Prefix => Prefix (Lhs),
2065 Get_Discriminant_Value (
2066 First_Discriminant (Lhs_Type),
2068 Stored_Constraint (Lhs_Type))));
2071 Lhs_Discr_Val := New_Copy (
2072 Get_Discriminant_Value (
2073 First_Discriminant (Lhs_Type),
2075 Stored_Constraint (Lhs_Type)));
2079 -- It is not possible to infer the discriminant since
2080 -- the subtype is not constrained.
2083 Make_Raise_Program_Error (Loc,
2084 Reason => PE_Unchecked_Union_Restriction);
2087 -- Rhs of the composite equality
2089 if Is_Constrained (Rhs_Type) then
2090 if Nkind (Rhs) = N_Selected_Component
2091 and then Has_Per_Object_Constraint (
2092 Entity (Selector_Name (Rhs)))
2095 Make_Selected_Component (Loc,
2096 Prefix => Prefix (Rhs),
2099 Get_Discriminant_Value (
2100 First_Discriminant (Rhs_Type),
2102 Stored_Constraint (Rhs_Type))));
2105 Rhs_Discr_Val := New_Copy (
2106 Get_Discriminant_Value (
2107 First_Discriminant (Rhs_Type),
2109 Stored_Constraint (Rhs_Type)));
2114 Make_Raise_Program_Error (Loc,
2115 Reason => PE_Unchecked_Union_Restriction);
2118 -- Call the TSS equality function with the inferred
2119 -- discriminant values.
2122 Make_Function_Call (Loc,
2123 Name => New_Reference_To (Eq_Op, Loc),
2124 Parameter_Associations => New_List (
2132 -- Shouldn't this be an else, we can't fall through the above
2136 Make_Function_Call (Loc,
2137 Name => New_Reference_To (Eq_Op, Loc),
2138 Parameter_Associations => New_List (Lhs, Rhs));
2142 return Expand_Record_Equality (Nod, Full_Type, Lhs, Rhs, Bodies);
2146 -- It can be a simple record or the full view of a scalar private
2148 return Make_Op_Eq (Loc, Left_Opnd => Lhs, Right_Opnd => Rhs);
2150 end Expand_Composite_Equality;
2152 ------------------------
2153 -- Expand_Concatenate --
2154 ------------------------
2156 procedure Expand_Concatenate (Cnode : Node_Id; Opnds : List_Id) is
2157 Loc : constant Source_Ptr := Sloc (Cnode);
2159 Atyp : constant Entity_Id := Base_Type (Etype (Cnode));
2160 -- Result type of concatenation
2162 Ctyp : constant Entity_Id := Base_Type (Component_Type (Etype (Cnode)));
2163 -- Component type. Elements of this component type can appear as one
2164 -- of the operands of concatenation as well as arrays.
2166 Istyp : constant Entity_Id := Etype (First_Index (Atyp));
2169 Ityp : constant Entity_Id := Base_Type (Istyp);
2170 -- Index type. This is the base type of the index subtype, and is used
2171 -- for all computed bounds (which may be out of range of Istyp in the
2172 -- case of null ranges).
2175 -- This is the type we use to do arithmetic to compute the bounds and
2176 -- lengths of operands. The choice of this type is a little subtle and
2177 -- is discussed in a separate section at the start of the body code.
2179 Concatenation_Error : exception;
2180 -- Raised if concatenation is sure to raise a CE
2182 Result_May_Be_Null : Boolean := True;
2183 -- Reset to False if at least one operand is encountered which is known
2184 -- at compile time to be non-null. Used for handling the special case
2185 -- of setting the high bound to the last operand high bound for a null
2186 -- result, thus ensuring a proper high bound in the super-flat case.
2188 N : constant Nat := List_Length (Opnds);
2189 -- Number of concatenation operands including possibly null operands
2192 -- Number of operands excluding any known to be null, except that the
2193 -- last operand is always retained, in case it provides the bounds for
2197 -- Current operand being processed in the loop through operands. After
2198 -- this loop is complete, always contains the last operand (which is not
2199 -- the same as Operands (NN), since null operands are skipped).
2201 -- Arrays describing the operands, only the first NN entries of each
2202 -- array are set (NN < N when we exclude known null operands).
2204 Is_Fixed_Length : array (1 .. N) of Boolean;
2205 -- True if length of corresponding operand known at compile time
2207 Operands : array (1 .. N) of Node_Id;
2208 -- Set to the corresponding entry in the Opnds list (but note that null
2209 -- operands are excluded, so not all entries in the list are stored).
2211 Fixed_Length : array (1 .. N) of Uint;
2212 -- Set to length of operand. Entries in this array are set only if the
2213 -- corresponding entry in Is_Fixed_Length is True.
2215 Opnd_Low_Bound : array (1 .. N) of Node_Id;
2216 -- Set to lower bound of operand. Either an integer literal in the case
2217 -- where the bound is known at compile time, else actual lower bound.
2218 -- The operand low bound is of type Ityp.
2220 Var_Length : array (1 .. N) of Entity_Id;
2221 -- Set to an entity of type Natural that contains the length of an
2222 -- operand whose length is not known at compile time. Entries in this
2223 -- array are set only if the corresponding entry in Is_Fixed_Length
2224 -- is False. The entity is of type Artyp.
2226 Aggr_Length : array (0 .. N) of Node_Id;
2227 -- The J'th entry in an expression node that represents the total length
2228 -- of operands 1 through J. It is either an integer literal node, or a
2229 -- reference to a constant entity with the right value, so it is fine
2230 -- to just do a Copy_Node to get an appropriate copy. The extra zero'th
2231 -- entry always is set to zero. The length is of type Artyp.
2233 Low_Bound : Node_Id;
2234 -- A tree node representing the low bound of the result (of type Ityp).
2235 -- This is either an integer literal node, or an identifier reference to
2236 -- a constant entity initialized to the appropriate value.
2238 Last_Opnd_High_Bound : Node_Id;
2239 -- A tree node representing the high bound of the last operand. This
2240 -- need only be set if the result could be null. It is used for the
2241 -- special case of setting the right high bound for a null result.
2242 -- This is of type Ityp.
2244 High_Bound : Node_Id;
2245 -- A tree node representing the high bound of the result (of type Ityp)
2248 -- Result of the concatenation (of type Ityp)
2250 Known_Non_Null_Operand_Seen : Boolean;
2251 -- Set True during generation of the assignements of operands into
2252 -- result once an operand known to be non-null has been seen.
2254 function Make_Artyp_Literal (Val : Nat) return Node_Id;
2255 -- This function makes an N_Integer_Literal node that is returned in
2256 -- analyzed form with the type set to Artyp. Importantly this literal
2257 -- is not flagged as static, so that if we do computations with it that
2258 -- result in statically detected out of range conditions, we will not
2259 -- generate error messages but instead warning messages.
2261 function To_Artyp (X : Node_Id) return Node_Id;
2262 -- Given a node of type Ityp, returns the corresponding value of type
2263 -- Artyp. For non-enumeration types, this is a plain integer conversion.
2264 -- For enum types, the Pos of the value is returned.
2266 function To_Ityp (X : Node_Id) return Node_Id;
2267 -- The inverse function (uses Val in the case of enumeration types)
2269 ------------------------
2270 -- Make_Artyp_Literal --
2271 ------------------------
2273 function Make_Artyp_Literal (Val : Nat) return Node_Id is
2274 Result : constant Node_Id := Make_Integer_Literal (Loc, Val);
2276 Set_Etype (Result, Artyp);
2277 Set_Analyzed (Result, True);
2278 Set_Is_Static_Expression (Result, False);
2280 end Make_Artyp_Literal;
2286 function To_Artyp (X : Node_Id) return Node_Id is
2288 if Ityp = Base_Type (Artyp) then
2291 elsif Is_Enumeration_Type (Ityp) then
2293 Make_Attribute_Reference (Loc,
2294 Prefix => New_Occurrence_Of (Ityp, Loc),
2295 Attribute_Name => Name_Pos,
2296 Expressions => New_List (X));
2299 return Convert_To (Artyp, X);
2307 function To_Ityp (X : Node_Id) return Node_Id is
2309 if Is_Enumeration_Type (Ityp) then
2311 Make_Attribute_Reference (Loc,
2312 Prefix => New_Occurrence_Of (Ityp, Loc),
2313 Attribute_Name => Name_Val,
2314 Expressions => New_List (X));
2316 -- Case where we will do a type conversion
2319 if Ityp = Base_Type (Artyp) then
2322 return Convert_To (Ityp, X);
2327 -- Local Declarations
2329 Opnd_Typ : Entity_Id;
2337 -- Choose an appropriate computational type
2339 -- We will be doing calculations of lengths and bounds in this routine
2340 -- and computing one from the other in some cases, e.g. getting the high
2341 -- bound by adding the length-1 to the low bound.
2343 -- We can't just use the index type, or even its base type for this
2344 -- purpose for two reasons. First it might be an enumeration type which
2345 -- is not suitable fo computations of any kind, and second it may simply
2346 -- not have enough range. For example if the index type is -128..+127
2347 -- then lengths can be up to 256, which is out of range of the type.
2349 -- For enumeration types, we can simply use Standard_Integer, this is
2350 -- sufficient since the actual number of enumeration literals cannot
2351 -- possibly exceed the range of integer (remember we will be doing the
2352 -- arithmetic with POS values, not representation values).
2354 if Is_Enumeration_Type (Ityp) then
2355 Artyp := Standard_Integer;
2357 -- If index type is Positive, we use the standard unsigned type, to give
2358 -- more room on the top of the range, obviating the need for an overflow
2359 -- check when creating the upper bound. This is needed to avoid junk
2360 -- overflow checks in the common case of String types.
2362 -- ??? Disabled for now
2364 -- elsif Istyp = Standard_Positive then
2365 -- Artyp := Standard_Unsigned;
2367 -- For modular types, we use a 32-bit modular type for types whose size
2368 -- is in the range 1-31 bits. For 32-bit unsigned types, we use the
2369 -- identity type, and for larger unsigned types we use 64-bits.
2371 elsif Is_Modular_Integer_Type (Ityp) then
2372 if RM_Size (Ityp) < RM_Size (Standard_Unsigned) then
2373 Artyp := Standard_Unsigned;
2374 elsif RM_Size (Ityp) = RM_Size (Standard_Unsigned) then
2377 Artyp := RTE (RE_Long_Long_Unsigned);
2380 -- Similar treatment for signed types
2383 if RM_Size (Ityp) < RM_Size (Standard_Integer) then
2384 Artyp := Standard_Integer;
2385 elsif RM_Size (Ityp) = RM_Size (Standard_Integer) then
2388 Artyp := Standard_Long_Long_Integer;
2392 -- Supply dummy entry at start of length array
2394 Aggr_Length (0) := Make_Artyp_Literal (0);
2396 -- Go through operands setting up the above arrays
2400 Opnd := Remove_Head (Opnds);
2401 Opnd_Typ := Etype (Opnd);
2403 -- The parent got messed up when we put the operands in a list,
2404 -- so now put back the proper parent for the saved operand.
2406 Set_Parent (Opnd, Parent (Cnode));
2408 -- Set will be True when we have setup one entry in the array
2412 -- Singleton element (or character literal) case
2414 if Base_Type (Opnd_Typ) = Ctyp then
2416 Operands (NN) := Opnd;
2417 Is_Fixed_Length (NN) := True;
2418 Fixed_Length (NN) := Uint_1;
2419 Result_May_Be_Null := False;
2421 -- Set low bound of operand (no need to set Last_Opnd_High_Bound
2422 -- since we know that the result cannot be null).
2424 Opnd_Low_Bound (NN) :=
2425 Make_Attribute_Reference (Loc,
2426 Prefix => New_Reference_To (Istyp, Loc),
2427 Attribute_Name => Name_First);
2431 -- String literal case (can only occur for strings of course)
2433 elsif Nkind (Opnd) = N_String_Literal then
2434 Len := String_Literal_Length (Opnd_Typ);
2437 Result_May_Be_Null := False;
2440 -- Capture last operand high bound if result could be null
2442 if J = N and then Result_May_Be_Null then
2443 Last_Opnd_High_Bound :=
2446 New_Copy_Tree (String_Literal_Low_Bound (Opnd_Typ)),
2447 Right_Opnd => Make_Integer_Literal (Loc, 1));
2450 -- Skip null string literal
2452 if J < N and then Len = 0 then
2457 Operands (NN) := Opnd;
2458 Is_Fixed_Length (NN) := True;
2460 -- Set length and bounds
2462 Fixed_Length (NN) := Len;
2464 Opnd_Low_Bound (NN) :=
2465 New_Copy_Tree (String_Literal_Low_Bound (Opnd_Typ));
2472 -- Check constrained case with known bounds
2474 if Is_Constrained (Opnd_Typ) then
2476 Index : constant Node_Id := First_Index (Opnd_Typ);
2477 Indx_Typ : constant Entity_Id := Etype (Index);
2478 Lo : constant Node_Id := Type_Low_Bound (Indx_Typ);
2479 Hi : constant Node_Id := Type_High_Bound (Indx_Typ);
2482 -- Fixed length constrained array type with known at compile
2483 -- time bounds is last case of fixed length operand.
2485 if Compile_Time_Known_Value (Lo)
2487 Compile_Time_Known_Value (Hi)
2490 Loval : constant Uint := Expr_Value (Lo);
2491 Hival : constant Uint := Expr_Value (Hi);
2492 Len : constant Uint :=
2493 UI_Max (Hival - Loval + 1, Uint_0);
2497 Result_May_Be_Null := False;
2500 -- Capture last operand bound if result could be null
2502 if J = N and then Result_May_Be_Null then
2503 Last_Opnd_High_Bound :=
2505 Make_Integer_Literal (Loc,
2506 Intval => Expr_Value (Hi)));
2509 -- Exclude null length case unless last operand
2511 if J < N and then Len = 0 then
2516 Operands (NN) := Opnd;
2517 Is_Fixed_Length (NN) := True;
2518 Fixed_Length (NN) := Len;
2520 Opnd_Low_Bound (NN) := To_Ityp (
2521 Make_Integer_Literal (Loc,
2522 Intval => Expr_Value (Lo)));
2530 -- All cases where the length is not known at compile time, or the
2531 -- special case of an operand which is known to be null but has a
2532 -- lower bound other than 1 or is other than a string type.
2537 -- Capture operand bounds
2539 Opnd_Low_Bound (NN) :=
2540 Make_Attribute_Reference (Loc,
2542 Duplicate_Subexpr (Opnd, Name_Req => True),
2543 Attribute_Name => Name_First);
2545 if J = N and Result_May_Be_Null then
2546 Last_Opnd_High_Bound :=
2548 Make_Attribute_Reference (Loc,
2550 Duplicate_Subexpr (Opnd, Name_Req => True),
2551 Attribute_Name => Name_Last));
2554 -- Capture length of operand in entity
2556 Operands (NN) := Opnd;
2557 Is_Fixed_Length (NN) := False;
2560 Make_Defining_Identifier (Loc,
2561 Chars => New_Internal_Name ('L'));
2563 Insert_Action (Cnode,
2564 Make_Object_Declaration (Loc,
2565 Defining_Identifier => Var_Length (NN),
2566 Constant_Present => True,
2568 Object_Definition =>
2569 New_Occurrence_Of (Artyp, Loc),
2572 Make_Attribute_Reference (Loc,
2574 Duplicate_Subexpr (Opnd, Name_Req => True),
2575 Attribute_Name => Name_Length)),
2577 Suppress => All_Checks);
2581 -- Set next entry in aggregate length array
2583 -- For first entry, make either integer literal for fixed length
2584 -- or a reference to the saved length for variable length.
2587 if Is_Fixed_Length (1) then
2589 Make_Integer_Literal (Loc,
2590 Intval => Fixed_Length (1));
2593 New_Reference_To (Var_Length (1), Loc);
2596 -- If entry is fixed length and only fixed lengths so far, make
2597 -- appropriate new integer literal adding new length.
2599 elsif Is_Fixed_Length (NN)
2600 and then Nkind (Aggr_Length (NN - 1)) = N_Integer_Literal
2603 Make_Integer_Literal (Loc,
2604 Intval => Fixed_Length (NN) + Intval (Aggr_Length (NN - 1)));
2606 -- All other cases, construct an addition node for the length and
2607 -- create an entity initialized to this length.
2611 Make_Defining_Identifier (Loc,
2612 Chars => New_Internal_Name ('L'));
2614 if Is_Fixed_Length (NN) then
2615 Clen := Make_Integer_Literal (Loc, Fixed_Length (NN));
2617 Clen := New_Reference_To (Var_Length (NN), Loc);
2620 Insert_Action (Cnode,
2621 Make_Object_Declaration (Loc,
2622 Defining_Identifier => Ent,
2623 Constant_Present => True,
2625 Object_Definition =>
2626 New_Occurrence_Of (Artyp, Loc),
2630 Left_Opnd => New_Copy (Aggr_Length (NN - 1)),
2631 Right_Opnd => Clen)),
2633 Suppress => All_Checks);
2635 Aggr_Length (NN) := Make_Identifier (Loc, Chars => Chars (Ent));
2642 -- If we have only skipped null operands, return the last operand
2649 -- If we have only one non-null operand, return it and we are done.
2650 -- There is one case in which this cannot be done, and that is when
2651 -- the sole operand is of the element type, in which case it must be
2652 -- converted to an array, and the easiest way of doing that is to go
2653 -- through the normal general circuit.
2656 and then Base_Type (Etype (Operands (1))) /= Ctyp
2658 Result := Operands (1);
2662 -- Cases where we have a real concatenation
2664 -- Next step is to find the low bound for the result array that we
2665 -- will allocate. The rules for this are in (RM 4.5.6(5-7)).
2667 -- If the ultimate ancestor of the index subtype is a constrained array
2668 -- definition, then the lower bound is that of the index subtype as
2669 -- specified by (RM 4.5.3(6)).
2671 -- The right test here is to go to the root type, and then the ultimate
2672 -- ancestor is the first subtype of this root type.
2674 if Is_Constrained (First_Subtype (Root_Type (Atyp))) then
2676 Make_Attribute_Reference (Loc,
2678 New_Occurrence_Of (First_Subtype (Root_Type (Atyp)), Loc),
2679 Attribute_Name => Name_First);
2681 -- If the first operand in the list has known length we know that
2682 -- the lower bound of the result is the lower bound of this operand.
2684 elsif Is_Fixed_Length (1) then
2685 Low_Bound := Opnd_Low_Bound (1);
2687 -- OK, we don't know the lower bound, we have to build a horrible
2688 -- expression actions node of the form
2690 -- if Cond1'Length /= 0 then
2693 -- if Opnd2'Length /= 0 then
2698 -- The nesting ends either when we hit an operand whose length is known
2699 -- at compile time, or on reaching the last operand, whose low bound we
2700 -- take unconditionally whether or not it is null. It's easiest to do
2701 -- this with a recursive procedure:
2705 function Get_Known_Bound (J : Nat) return Node_Id;
2706 -- Returns the lower bound determined by operands J .. NN
2708 ---------------------
2709 -- Get_Known_Bound --
2710 ---------------------
2712 function Get_Known_Bound (J : Nat) return Node_Id is
2714 if Is_Fixed_Length (J) or else J = NN then
2715 return New_Copy (Opnd_Low_Bound (J));
2719 Make_Conditional_Expression (Loc,
2720 Expressions => New_List (
2723 Left_Opnd => New_Reference_To (Var_Length (J), Loc),
2724 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2726 New_Copy (Opnd_Low_Bound (J)),
2727 Get_Known_Bound (J + 1)));
2729 end Get_Known_Bound;
2733 Make_Defining_Identifier (Loc, Chars => New_Internal_Name ('L'));
2735 Insert_Action (Cnode,
2736 Make_Object_Declaration (Loc,
2737 Defining_Identifier => Ent,
2738 Constant_Present => True,
2739 Object_Definition => New_Occurrence_Of (Ityp, Loc),
2740 Expression => Get_Known_Bound (1)),
2741 Suppress => All_Checks);
2743 Low_Bound := New_Reference_To (Ent, Loc);
2747 -- Now we can safely compute the upper bound, normally
2748 -- Low_Bound + Length - 1.
2753 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
2755 Make_Op_Subtract (Loc,
2756 Left_Opnd => New_Copy (Aggr_Length (NN)),
2757 Right_Opnd => Make_Artyp_Literal (1))));
2759 -- Note that calculation of the high bound may cause overflow in some
2760 -- very weird cases, so in the general case we need an overflow check
2761 -- on the high bound. We can avoid this for the common case of string
2762 -- types since we chose a wider range for the arithmetic type.
2764 if Istyp /= Standard_Positive then
2765 Activate_Overflow_Check (High_Bound);
2768 -- Handle the exceptional case where the result is null, in which case
2769 -- case the bounds come from the last operand (so that we get the proper
2770 -- bounds if the last operand is super-flat).
2772 if Result_May_Be_Null then
2774 Make_Conditional_Expression (Loc,
2775 Expressions => New_List (
2777 Left_Opnd => New_Copy (Aggr_Length (NN)),
2778 Right_Opnd => Make_Artyp_Literal (0)),
2779 Last_Opnd_High_Bound,
2783 -- Now we construct an array object with appropriate bounds
2786 Make_Defining_Identifier (Loc,
2787 Chars => New_Internal_Name ('S'));
2789 -- If the bound is statically known to be out of range, we do not want
2790 -- to abort, we want a warning and a runtime constraint error. Note that
2791 -- we have arranged that the result will not be treated as a static
2792 -- constant, so we won't get an illegality during this insertion.
2794 Insert_Action (Cnode,
2795 Make_Object_Declaration (Loc,
2796 Defining_Identifier => Ent,
2797 Object_Definition =>
2798 Make_Subtype_Indication (Loc,
2799 Subtype_Mark => New_Occurrence_Of (Atyp, Loc),
2801 Make_Index_Or_Discriminant_Constraint (Loc,
2802 Constraints => New_List (
2804 Low_Bound => Low_Bound,
2805 High_Bound => High_Bound))))),
2806 Suppress => All_Checks);
2808 -- Catch the static out of range case now
2810 if Raises_Constraint_Error (High_Bound) then
2811 raise Concatenation_Error;
2814 -- Now we will generate the assignments to do the actual concatenation
2816 Known_Non_Null_Operand_Seen := False;
2818 for J in 1 .. NN loop
2820 Lo : constant Node_Id :=
2822 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
2823 Right_Opnd => Aggr_Length (J - 1));
2825 Hi : constant Node_Id :=
2827 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
2829 Make_Op_Subtract (Loc,
2830 Left_Opnd => Aggr_Length (J),
2831 Right_Opnd => Make_Artyp_Literal (1)));
2834 -- Singleton case, simple assignment
2836 if Base_Type (Etype (Operands (J))) = Ctyp then
2837 Known_Non_Null_Operand_Seen := True;
2838 Insert_Action (Cnode,
2839 Make_Assignment_Statement (Loc,
2841 Make_Indexed_Component (Loc,
2842 Prefix => New_Occurrence_Of (Ent, Loc),
2843 Expressions => New_List (To_Ityp (Lo))),
2844 Expression => Operands (J)),
2845 Suppress => All_Checks);
2847 -- Array case, slice assignment, skipped when argument is fixed
2848 -- length and known to be null.
2850 elsif (not Is_Fixed_Length (J)) or else (Fixed_Length (J) > 0) then
2853 Make_Assignment_Statement (Loc,
2857 New_Occurrence_Of (Ent, Loc),
2860 Low_Bound => To_Ityp (Lo),
2861 High_Bound => To_Ityp (Hi))),
2862 Expression => Operands (J));
2864 if Is_Fixed_Length (J) then
2865 Known_Non_Null_Operand_Seen := True;
2867 elsif not Known_Non_Null_Operand_Seen then
2869 -- Here if operand length is not statically known and no
2870 -- operand known to be non-null has been processed yet.
2871 -- If operand length is 0, we do not need to perform the
2872 -- assignment, and we must avoid the evaluation of the
2873 -- high bound of the slice, since it may underflow if the
2874 -- low bound is Ityp'First.
2877 Make_Implicit_If_Statement (Cnode,
2881 New_Occurrence_Of (Var_Length (J), Loc),
2882 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2887 Insert_Action (Cnode, Assign, Suppress => All_Checks);
2893 -- Finally we build the result, which is a reference to the array object
2895 Result := New_Reference_To (Ent, Loc);
2898 Rewrite (Cnode, Result);
2899 Analyze_And_Resolve (Cnode, Atyp);
2902 when Concatenation_Error =>
2904 -- Kill warning generated for the declaration of the static out of
2905 -- range high bound, and instead generate a Constraint_Error with
2906 -- an appropriate specific message.
2908 Kill_Dead_Code (Declaration_Node (Entity (High_Bound)));
2909 Apply_Compile_Time_Constraint_Error
2911 Msg => "concatenation result upper bound out of range?",
2912 Reason => CE_Range_Check_Failed);
2913 -- Set_Etype (Cnode, Atyp);
2914 end Expand_Concatenate;
2916 ------------------------
2917 -- Expand_N_Allocator --
2918 ------------------------
2920 procedure Expand_N_Allocator (N : Node_Id) is
2921 PtrT : constant Entity_Id := Etype (N);
2922 Dtyp : constant Entity_Id := Designated_Type (PtrT);
2923 Etyp : constant Entity_Id := Etype (Expression (N));
2924 Loc : constant Source_Ptr := Sloc (N);
2929 procedure Complete_Coextension_Finalization;
2930 -- Generate finalization calls for all nested coextensions of N. This
2931 -- routine may allocate list controllers if necessary.
2933 procedure Rewrite_Coextension (N : Node_Id);
2934 -- Static coextensions have the same lifetime as the entity they
2935 -- constrain. Such occurrences can be rewritten as aliased objects
2936 -- and their unrestricted access used instead of the coextension.
2938 ---------------------------------------
2939 -- Complete_Coextension_Finalization --
2940 ---------------------------------------
2942 procedure Complete_Coextension_Finalization is
2944 Coext_Elmt : Elmt_Id;
2948 function Inside_A_Return_Statement (N : Node_Id) return Boolean;
2949 -- Determine whether node N is part of a return statement
2951 function Needs_Initialization_Call (N : Node_Id) return Boolean;
2952 -- Determine whether node N is a subtype indicator allocator which
2953 -- acts a coextension. Such coextensions need initialization.
2955 -------------------------------
2956 -- Inside_A_Return_Statement --
2957 -------------------------------
2959 function Inside_A_Return_Statement (N : Node_Id) return Boolean is
2964 while Present (P) loop
2966 (P, N_Extended_Return_Statement, N_Simple_Return_Statement)
2970 -- Stop the traversal when we reach a subprogram body
2972 elsif Nkind (P) = N_Subprogram_Body then
2980 end Inside_A_Return_Statement;
2982 -------------------------------
2983 -- Needs_Initialization_Call --
2984 -------------------------------
2986 function Needs_Initialization_Call (N : Node_Id) return Boolean is
2990 if Nkind (N) = N_Explicit_Dereference
2991 and then Nkind (Prefix (N)) = N_Identifier
2992 and then Nkind (Parent (Entity (Prefix (N)))) =
2993 N_Object_Declaration
2995 Obj_Decl := Parent (Entity (Prefix (N)));
2998 Present (Expression (Obj_Decl))
2999 and then Nkind (Expression (Obj_Decl)) = N_Allocator
3000 and then Nkind (Expression (Expression (Obj_Decl))) /=
3001 N_Qualified_Expression;
3005 end Needs_Initialization_Call;
3007 -- Start of processing for Complete_Coextension_Finalization
3010 -- When a coextension root is inside a return statement, we need to
3011 -- use the finalization chain of the function's scope. This does not
3012 -- apply for controlled named access types because in those cases we
3013 -- can use the finalization chain of the type itself.
3015 if Inside_A_Return_Statement (N)
3017 (Ekind (PtrT) = E_Anonymous_Access_Type
3019 (Ekind (PtrT) = E_Access_Type
3020 and then No (Associated_Final_Chain (PtrT))))
3024 Outer_S : Entity_Id;
3025 S : Entity_Id := Current_Scope;
3028 while Present (S) and then S /= Standard_Standard loop
3029 if Ekind (S) = E_Function then
3030 Outer_S := Scope (S);
3032 -- Retrieve the declaration of the body
3034 Decl := Parent (Parent (
3035 Corresponding_Body (Parent (Parent (S)))));
3042 -- Push the scope of the function body since we are inserting
3043 -- the list before the body, but we are currently in the body
3044 -- itself. Override the finalization list of PtrT since the
3045 -- finalization context is now different.
3047 Push_Scope (Outer_S);
3048 Build_Final_List (Decl, PtrT);
3052 -- The root allocator may not be controlled, but it still needs a
3053 -- finalization list for all nested coextensions.
3055 elsif No (Associated_Final_Chain (PtrT)) then
3056 Build_Final_List (N, PtrT);
3060 Make_Selected_Component (Loc,
3062 New_Reference_To (Associated_Final_Chain (PtrT), Loc),
3064 Make_Identifier (Loc, Name_F));
3066 Coext_Elmt := First_Elmt (Coextensions (N));
3067 while Present (Coext_Elmt) loop
3068 Coext := Node (Coext_Elmt);
3073 if Nkind (Coext) = N_Identifier then
3075 Make_Unchecked_Type_Conversion (Loc,
3076 Subtype_Mark => New_Reference_To (Etype (Coext), Loc),
3078 Make_Explicit_Dereference (Loc,
3079 Prefix => New_Copy_Tree (Coext)));
3081 Ref := New_Copy_Tree (Coext);
3084 -- No initialization call if not allowed
3086 Check_Restriction (No_Default_Initialization, N);
3088 if not Restriction_Active (No_Default_Initialization) then
3092 -- attach_to_final_list (Ref, Flist, 2)
3094 if Needs_Initialization_Call (Coext) then
3098 Typ => Etype (Coext),
3100 With_Attach => Make_Integer_Literal (Loc, Uint_2)));
3103 -- attach_to_final_list (Ref, Flist, 2)
3109 Flist_Ref => New_Copy_Tree (Flist),
3110 With_Attach => Make_Integer_Literal (Loc, Uint_2)));
3114 Next_Elmt (Coext_Elmt);
3116 end Complete_Coextension_Finalization;
3118 -------------------------
3119 -- Rewrite_Coextension --
3120 -------------------------
3122 procedure Rewrite_Coextension (N : Node_Id) is
3123 Temp : constant Node_Id :=
3124 Make_Defining_Identifier (Loc,
3125 New_Internal_Name ('C'));
3128 -- Cnn : aliased Etyp;
3130 Decl : constant Node_Id :=
3131 Make_Object_Declaration (Loc,
3132 Defining_Identifier => Temp,
3133 Aliased_Present => True,
3134 Object_Definition =>
3135 New_Occurrence_Of (Etyp, Loc));
3139 if Nkind (Expression (N)) = N_Qualified_Expression then
3140 Set_Expression (Decl, Expression (Expression (N)));
3143 -- Find the proper insertion node for the declaration
3146 while Present (Nod) loop
3147 exit when Nkind (Nod) in N_Statement_Other_Than_Procedure_Call
3148 or else Nkind (Nod) = N_Procedure_Call_Statement
3149 or else Nkind (Nod) in N_Declaration;
3150 Nod := Parent (Nod);
3153 Insert_Before (Nod, Decl);
3157 Make_Attribute_Reference (Loc,
3158 Prefix => New_Occurrence_Of (Temp, Loc),
3159 Attribute_Name => Name_Unrestricted_Access));
3161 Analyze_And_Resolve (N, PtrT);
3162 end Rewrite_Coextension;
3164 -- Start of processing for Expand_N_Allocator
3167 -- RM E.2.3(22). We enforce that the expected type of an allocator
3168 -- shall not be a remote access-to-class-wide-limited-private type
3170 -- Why is this being done at expansion time, seems clearly wrong ???
3172 Validate_Remote_Access_To_Class_Wide_Type (N);
3174 -- Set the Storage Pool
3176 Set_Storage_Pool (N, Associated_Storage_Pool (Root_Type (PtrT)));
3178 if Present (Storage_Pool (N)) then
3179 if Is_RTE (Storage_Pool (N), RE_SS_Pool) then
3180 if VM_Target = No_VM then
3181 Set_Procedure_To_Call (N, RTE (RE_SS_Allocate));
3184 elsif Is_Class_Wide_Type (Etype (Storage_Pool (N))) then
3185 Set_Procedure_To_Call (N, RTE (RE_Allocate_Any));
3188 Set_Procedure_To_Call (N,
3189 Find_Prim_Op (Etype (Storage_Pool (N)), Name_Allocate));
3193 -- Under certain circumstances we can replace an allocator by an access
3194 -- to statically allocated storage. The conditions, as noted in AARM
3195 -- 3.10 (10c) are as follows:
3197 -- Size and initial value is known at compile time
3198 -- Access type is access-to-constant
3200 -- The allocator is not part of a constraint on a record component,
3201 -- because in that case the inserted actions are delayed until the
3202 -- record declaration is fully analyzed, which is too late for the
3203 -- analysis of the rewritten allocator.
3205 if Is_Access_Constant (PtrT)
3206 and then Nkind (Expression (N)) = N_Qualified_Expression
3207 and then Compile_Time_Known_Value (Expression (Expression (N)))
3208 and then Size_Known_At_Compile_Time (Etype (Expression
3210 and then not Is_Record_Type (Current_Scope)
3212 -- Here we can do the optimization. For the allocator
3216 -- We insert an object declaration
3218 -- Tnn : aliased x := y;
3220 -- and replace the allocator by Tnn'Unrestricted_Access. Tnn is
3221 -- marked as requiring static allocation.
3224 Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
3226 Desig := Subtype_Mark (Expression (N));
3228 -- If context is constrained, use constrained subtype directly,
3229 -- so that the constant is not labelled as having a nominally
3230 -- unconstrained subtype.
3232 if Entity (Desig) = Base_Type (Dtyp) then
3233 Desig := New_Occurrence_Of (Dtyp, Loc);
3237 Make_Object_Declaration (Loc,
3238 Defining_Identifier => Temp,
3239 Aliased_Present => True,
3240 Constant_Present => Is_Access_Constant (PtrT),
3241 Object_Definition => Desig,
3242 Expression => Expression (Expression (N))));
3245 Make_Attribute_Reference (Loc,
3246 Prefix => New_Occurrence_Of (Temp, Loc),
3247 Attribute_Name => Name_Unrestricted_Access));
3249 Analyze_And_Resolve (N, PtrT);
3251 -- We set the variable as statically allocated, since we don't want
3252 -- it going on the stack of the current procedure!
3254 Set_Is_Statically_Allocated (Temp);
3258 -- Same if the allocator is an access discriminant for a local object:
3259 -- instead of an allocator we create a local value and constrain the
3260 -- the enclosing object with the corresponding access attribute.
3262 if Is_Static_Coextension (N) then
3263 Rewrite_Coextension (N);
3267 -- The current allocator creates an object which may contain nested
3268 -- coextensions. Use the current allocator's finalization list to
3269 -- generate finalization call for all nested coextensions.
3271 if Is_Coextension_Root (N) then
3272 Complete_Coextension_Finalization;
3275 -- Handle case of qualified expression (other than optimization above)
3277 if Nkind (Expression (N)) = N_Qualified_Expression then
3278 Expand_Allocator_Expression (N);
3282 -- If the allocator is for a type which requires initialization, and
3283 -- there is no initial value (i.e. operand is a subtype indication
3284 -- rather than a qualified expression), then we must generate a call to
3285 -- the initialization routine using an expressions action node:
3287 -- [Pnnn : constant ptr_T := new (T); Init (Pnnn.all,...); Pnnn]
3289 -- Here ptr_T is the pointer type for the allocator, and T is the
3290 -- subtype of the allocator. A special case arises if the designated
3291 -- type of the access type is a task or contains tasks. In this case
3292 -- the call to Init (Temp.all ...) is replaced by code that ensures
3293 -- that tasks get activated (see Exp_Ch9.Build_Task_Allocate_Block
3294 -- for details). In addition, if the type T is a task T, then the
3295 -- first argument to Init must be converted to the task record type.
3298 T : constant Entity_Id := Entity (Expression (N));
3306 Temp_Decl : Node_Id;
3307 Temp_Type : Entity_Id;
3308 Attach_Level : Uint;
3311 if No_Initialization (N) then
3314 -- Case of no initialization procedure present
3316 elsif not Has_Non_Null_Base_Init_Proc (T) then
3318 -- Case of simple initialization required
3320 if Needs_Simple_Initialization (T) then
3321 Check_Restriction (No_Default_Initialization, N);
3322 Rewrite (Expression (N),
3323 Make_Qualified_Expression (Loc,
3324 Subtype_Mark => New_Occurrence_Of (T, Loc),
3325 Expression => Get_Simple_Init_Val (T, N)));
3327 Analyze_And_Resolve (Expression (Expression (N)), T);
3328 Analyze_And_Resolve (Expression (N), T);
3329 Set_Paren_Count (Expression (Expression (N)), 1);
3330 Expand_N_Allocator (N);
3332 -- No initialization required
3338 -- Case of initialization procedure present, must be called
3341 Check_Restriction (No_Default_Initialization, N);
3343 if not Restriction_Active (No_Default_Initialization) then
3344 Init := Base_Init_Proc (T);
3346 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
3348 -- Construct argument list for the initialization routine call
3351 Make_Explicit_Dereference (Loc,
3352 Prefix => New_Reference_To (Temp, Loc));
3353 Set_Assignment_OK (Arg1);
3356 -- The initialization procedure expects a specific type. if the
3357 -- context is access to class wide, indicate that the object
3358 -- being allocated has the right specific type.
3360 if Is_Class_Wide_Type (Dtyp) then
3361 Arg1 := Unchecked_Convert_To (T, Arg1);
3364 -- If designated type is a concurrent type or if it is private
3365 -- type whose definition is a concurrent type, the first
3366 -- argument in the Init routine has to be unchecked conversion
3367 -- to the corresponding record type. If the designated type is
3368 -- a derived type, we also convert the argument to its root
3371 if Is_Concurrent_Type (T) then
3373 Unchecked_Convert_To (Corresponding_Record_Type (T), Arg1);
3375 elsif Is_Private_Type (T)
3376 and then Present (Full_View (T))
3377 and then Is_Concurrent_Type (Full_View (T))
3380 Unchecked_Convert_To
3381 (Corresponding_Record_Type (Full_View (T)), Arg1);
3383 elsif Etype (First_Formal (Init)) /= Base_Type (T) then
3385 Ftyp : constant Entity_Id := Etype (First_Formal (Init));
3387 Arg1 := OK_Convert_To (Etype (Ftyp), Arg1);
3388 Set_Etype (Arg1, Ftyp);
3392 Args := New_List (Arg1);
3394 -- For the task case, pass the Master_Id of the access type as
3395 -- the value of the _Master parameter, and _Chain as the value
3396 -- of the _Chain parameter (_Chain will be defined as part of
3397 -- the generated code for the allocator).
3399 -- In Ada 2005, the context may be a function that returns an
3400 -- anonymous access type. In that case the Master_Id has been
3401 -- created when expanding the function declaration.
3403 if Has_Task (T) then
3404 if No (Master_Id (Base_Type (PtrT))) then
3406 -- If we have a non-library level task with restriction
3407 -- No_Task_Hierarchy set, then no point in expanding.
3409 if not Is_Library_Level_Entity (T)
3410 and then Restriction_Active (No_Task_Hierarchy)
3415 -- The designated type was an incomplete type, and the
3416 -- access type did not get expanded. Salvage it now.
3418 pragma Assert (Present (Parent (Base_Type (PtrT))));
3419 Expand_N_Full_Type_Declaration
3420 (Parent (Base_Type (PtrT)));
3423 -- If the context of the allocator is a declaration or an
3424 -- assignment, we can generate a meaningful image for it,
3425 -- even though subsequent assignments might remove the
3426 -- connection between task and entity. We build this image
3427 -- when the left-hand side is a simple variable, a simple
3428 -- indexed assignment or a simple selected component.
3430 if Nkind (Parent (N)) = N_Assignment_Statement then
3432 Nam : constant Node_Id := Name (Parent (N));
3435 if Is_Entity_Name (Nam) then
3437 Build_Task_Image_Decls
3440 (Entity (Nam), Sloc (Nam)), T);
3443 (Nam, N_Indexed_Component, N_Selected_Component)
3444 and then Is_Entity_Name (Prefix (Nam))
3447 Build_Task_Image_Decls
3448 (Loc, Nam, Etype (Prefix (Nam)));
3450 Decls := Build_Task_Image_Decls (Loc, T, T);
3454 elsif Nkind (Parent (N)) = N_Object_Declaration then
3456 Build_Task_Image_Decls
3457 (Loc, Defining_Identifier (Parent (N)), T);
3460 Decls := Build_Task_Image_Decls (Loc, T, T);
3465 (Master_Id (Base_Type (Root_Type (PtrT))), Loc));
3466 Append_To (Args, Make_Identifier (Loc, Name_uChain));
3468 Decl := Last (Decls);
3470 New_Occurrence_Of (Defining_Identifier (Decl), Loc));
3472 -- Has_Task is false, Decls not used
3478 -- Add discriminants if discriminated type
3481 Dis : Boolean := False;
3485 if Has_Discriminants (T) then
3489 elsif Is_Private_Type (T)
3490 and then Present (Full_View (T))
3491 and then Has_Discriminants (Full_View (T))
3494 Typ := Full_View (T);
3499 -- If the allocated object will be constrained by the
3500 -- default values for discriminants, then build a subtype
3501 -- with those defaults, and change the allocated subtype
3502 -- to that. Note that this happens in fewer cases in Ada
3505 if not Is_Constrained (Typ)
3506 and then Present (Discriminant_Default_Value
3507 (First_Discriminant (Typ)))
3508 and then (Ada_Version < Ada_05
3510 not Has_Constrained_Partial_View (Typ))
3512 Typ := Build_Default_Subtype (Typ, N);
3513 Set_Expression (N, New_Reference_To (Typ, Loc));
3516 Discr := First_Elmt (Discriminant_Constraint (Typ));
3517 while Present (Discr) loop
3518 Nod := Node (Discr);
3519 Append (New_Copy_Tree (Node (Discr)), Args);
3521 -- AI-416: when the discriminant constraint is an
3522 -- anonymous access type make sure an accessibility
3523 -- check is inserted if necessary (3.10.2(22.q/2))
3525 if Ada_Version >= Ada_05
3527 Ekind (Etype (Nod)) = E_Anonymous_Access_Type
3529 Apply_Accessibility_Check
3530 (Nod, Typ, Insert_Node => Nod);
3538 -- We set the allocator as analyzed so that when we analyze the
3539 -- expression actions node, we do not get an unwanted recursive
3540 -- expansion of the allocator expression.
3542 Set_Analyzed (N, True);
3543 Nod := Relocate_Node (N);
3545 -- Here is the transformation:
3547 -- output: Temp : constant ptr_T := new T;
3548 -- Init (Temp.all, ...);
3549 -- <CTRL> Attach_To_Final_List (Finalizable (Temp.all));
3550 -- <CTRL> Initialize (Finalizable (Temp.all));
3552 -- Here ptr_T is the pointer type for the allocator, and is the
3553 -- subtype of the allocator.
3556 Make_Object_Declaration (Loc,
3557 Defining_Identifier => Temp,
3558 Constant_Present => True,
3559 Object_Definition => New_Reference_To (Temp_Type, Loc),
3562 Set_Assignment_OK (Temp_Decl);
3563 Insert_Action (N, Temp_Decl, Suppress => All_Checks);
3565 -- If the designated type is a task type or contains tasks,
3566 -- create block to activate created tasks, and insert
3567 -- declaration for Task_Image variable ahead of call.
3569 if Has_Task (T) then
3571 L : constant List_Id := New_List;
3574 Build_Task_Allocate_Block (L, Nod, Args);
3576 Insert_List_Before (First (Declarations (Blk)), Decls);
3577 Insert_Actions (N, L);
3582 Make_Procedure_Call_Statement (Loc,
3583 Name => New_Reference_To (Init, Loc),
3584 Parameter_Associations => Args));
3587 if Needs_Finalization (T) then
3589 -- Postpone the generation of a finalization call for the
3590 -- current allocator if it acts as a coextension.
3592 if Is_Dynamic_Coextension (N) then
3593 if No (Coextensions (N)) then
3594 Set_Coextensions (N, New_Elmt_List);
3597 Append_Elmt (New_Copy_Tree (Arg1), Coextensions (N));
3601 Get_Allocator_Final_List (N, Base_Type (T), PtrT);
3603 -- Anonymous access types created for access parameters
3604 -- are attached to an explicitly constructed controller,
3605 -- which ensures that they can be finalized properly,
3606 -- even if their deallocation might not happen. The list
3607 -- associated with the controller is doubly-linked. For
3608 -- other anonymous access types, the object may end up
3609 -- on the global final list which is singly-linked.
3610 -- Work needed for access discriminants in Ada 2005 ???
3612 if Ekind (PtrT) = E_Anonymous_Access_Type
3614 Nkind (Associated_Node_For_Itype (PtrT))
3615 not in N_Subprogram_Specification
3617 Attach_Level := Uint_1;
3619 Attach_Level := Uint_2;
3624 Ref => New_Copy_Tree (Arg1),
3627 With_Attach => Make_Integer_Literal (Loc,
3628 Intval => Attach_Level)));
3632 Rewrite (N, New_Reference_To (Temp, Loc));
3633 Analyze_And_Resolve (N, PtrT);
3638 -- Ada 2005 (AI-251): If the allocator is for a class-wide interface
3639 -- object that has been rewritten as a reference, we displace "this"
3640 -- to reference properly its secondary dispatch table.
3642 if Nkind (N) = N_Identifier
3643 and then Is_Interface (Dtyp)
3645 Displace_Allocator_Pointer (N);
3649 when RE_Not_Available =>
3651 end Expand_N_Allocator;
3653 -----------------------
3654 -- Expand_N_And_Then --
3655 -----------------------
3657 -- Expand into conditional expression if Actions present, and also deal
3658 -- with optimizing case of arguments being True or False.
3660 procedure Expand_N_And_Then (N : Node_Id) is
3661 Loc : constant Source_Ptr := Sloc (N);
3662 Typ : constant Entity_Id := Etype (N);
3663 Left : constant Node_Id := Left_Opnd (N);
3664 Right : constant Node_Id := Right_Opnd (N);
3668 -- Deal with non-standard booleans
3670 if Is_Boolean_Type (Typ) then
3671 Adjust_Condition (Left);
3672 Adjust_Condition (Right);
3673 Set_Etype (N, Standard_Boolean);
3676 -- Check for cases where left argument is known to be True or False
3678 if Compile_Time_Known_Value (Left) then
3680 -- If left argument is True, change (True and then Right) to Right.
3681 -- Any actions associated with Right will be executed unconditionally
3682 -- and can thus be inserted into the tree unconditionally.
3684 if Expr_Value_E (Left) = Standard_True then
3685 if Present (Actions (N)) then
3686 Insert_Actions (N, Actions (N));
3691 -- If left argument is False, change (False and then Right) to False.
3692 -- In this case we can forget the actions associated with Right,
3693 -- since they will never be executed.
3695 else pragma Assert (Expr_Value_E (Left) = Standard_False);
3696 Kill_Dead_Code (Right);
3697 Kill_Dead_Code (Actions (N));
3698 Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
3701 Adjust_Result_Type (N, Typ);
3705 -- If Actions are present, we expand
3707 -- left and then right
3711 -- if left then right else false end
3713 -- with the actions becoming the Then_Actions of the conditional
3714 -- expression. This conditional expression is then further expanded
3715 -- (and will eventually disappear)
3717 if Present (Actions (N)) then
3718 Actlist := Actions (N);
3720 Make_Conditional_Expression (Loc,
3721 Expressions => New_List (
3724 New_Occurrence_Of (Standard_False, Loc))));
3726 Set_Then_Actions (N, Actlist);
3727 Analyze_And_Resolve (N, Standard_Boolean);
3728 Adjust_Result_Type (N, Typ);
3732 -- No actions present, check for cases of right argument True/False
3734 if Compile_Time_Known_Value (Right) then
3736 -- Change (Left and then True) to Left. Note that we know there are
3737 -- no actions associated with the True operand, since we just checked
3738 -- for this case above.
3740 if Expr_Value_E (Right) = Standard_True then
3743 -- Change (Left and then False) to False, making sure to preserve any
3744 -- side effects associated with the Left operand.
3746 else pragma Assert (Expr_Value_E (Right) = Standard_False);
3747 Remove_Side_Effects (Left);
3749 (N, New_Occurrence_Of (Standard_False, Loc));
3753 Adjust_Result_Type (N, Typ);
3754 end Expand_N_And_Then;
3756 -------------------------------------
3757 -- Expand_N_Conditional_Expression --
3758 -------------------------------------
3760 -- Expand into expression actions if then/else actions present
3762 procedure Expand_N_Conditional_Expression (N : Node_Id) is
3763 Loc : constant Source_Ptr := Sloc (N);
3764 Cond : constant Node_Id := First (Expressions (N));
3765 Thenx : constant Node_Id := Next (Cond);
3766 Elsex : constant Node_Id := Next (Thenx);
3767 Typ : constant Entity_Id := Etype (N);
3772 -- If either then or else actions are present, then given:
3774 -- if cond then then-expr else else-expr end
3776 -- we insert the following sequence of actions (using Insert_Actions):
3781 -- Cnn := then-expr;
3787 -- and replace the conditional expression by a reference to Cnn
3789 if Present (Then_Actions (N)) or else Present (Else_Actions (N)) then
3790 Cnn := Make_Defining_Identifier (Loc, New_Internal_Name ('C'));
3793 Make_Implicit_If_Statement (N,
3794 Condition => Relocate_Node (Cond),
3796 Then_Statements => New_List (
3797 Make_Assignment_Statement (Sloc (Thenx),
3798 Name => New_Occurrence_Of (Cnn, Sloc (Thenx)),
3799 Expression => Relocate_Node (Thenx))),
3801 Else_Statements => New_List (
3802 Make_Assignment_Statement (Sloc (Elsex),
3803 Name => New_Occurrence_Of (Cnn, Sloc (Elsex)),
3804 Expression => Relocate_Node (Elsex))));
3806 Set_Assignment_OK (Name (First (Then_Statements (New_If))));
3807 Set_Assignment_OK (Name (First (Else_Statements (New_If))));
3809 if Present (Then_Actions (N)) then
3811 (First (Then_Statements (New_If)), Then_Actions (N));
3814 if Present (Else_Actions (N)) then
3816 (First (Else_Statements (New_If)), Else_Actions (N));
3819 Rewrite (N, New_Occurrence_Of (Cnn, Loc));
3822 Make_Object_Declaration (Loc,
3823 Defining_Identifier => Cnn,
3824 Object_Definition => New_Occurrence_Of (Typ, Loc)));
3826 Insert_Action (N, New_If);
3827 Analyze_And_Resolve (N, Typ);
3829 end Expand_N_Conditional_Expression;
3831 -----------------------------------
3832 -- Expand_N_Explicit_Dereference --
3833 -----------------------------------
3835 procedure Expand_N_Explicit_Dereference (N : Node_Id) is
3837 -- Insert explicit dereference call for the checked storage pool case
3839 Insert_Dereference_Action (Prefix (N));
3840 end Expand_N_Explicit_Dereference;
3846 procedure Expand_N_In (N : Node_Id) is
3847 Loc : constant Source_Ptr := Sloc (N);
3848 Rtyp : constant Entity_Id := Etype (N);
3849 Lop : constant Node_Id := Left_Opnd (N);
3850 Rop : constant Node_Id := Right_Opnd (N);
3851 Static : constant Boolean := Is_OK_Static_Expression (N);
3853 procedure Substitute_Valid_Check;
3854 -- Replaces node N by Lop'Valid. This is done when we have an explicit
3855 -- test for the left operand being in range of its subtype.
3857 ----------------------------
3858 -- Substitute_Valid_Check --
3859 ----------------------------
3861 procedure Substitute_Valid_Check is
3864 Make_Attribute_Reference (Loc,
3865 Prefix => Relocate_Node (Lop),
3866 Attribute_Name => Name_Valid));
3868 Analyze_And_Resolve (N, Rtyp);
3870 Error_Msg_N ("?explicit membership test may be optimized away", N);
3871 Error_Msg_N ("\?use ''Valid attribute instead", N);
3873 end Substitute_Valid_Check;
3875 -- Start of processing for Expand_N_In
3878 -- Check case of explicit test for an expression in range of its
3879 -- subtype. This is suspicious usage and we replace it with a 'Valid
3880 -- test and give a warning.
3882 if Is_Scalar_Type (Etype (Lop))
3883 and then Nkind (Rop) in N_Has_Entity
3884 and then Etype (Lop) = Entity (Rop)
3885 and then Comes_From_Source (N)
3886 and then VM_Target = No_VM
3888 Substitute_Valid_Check;
3892 -- Do validity check on operands
3894 if Validity_Checks_On and Validity_Check_Operands then
3895 Ensure_Valid (Left_Opnd (N));
3896 Validity_Check_Range (Right_Opnd (N));
3899 -- Case of explicit range
3901 if Nkind (Rop) = N_Range then
3903 Lo : constant Node_Id := Low_Bound (Rop);
3904 Hi : constant Node_Id := High_Bound (Rop);
3906 Ltyp : constant Entity_Id := Etype (Lop);
3908 Lo_Orig : constant Node_Id := Original_Node (Lo);
3909 Hi_Orig : constant Node_Id := Original_Node (Hi);
3911 Lcheck : Compare_Result;
3912 Ucheck : Compare_Result;
3914 Warn1 : constant Boolean :=
3915 Constant_Condition_Warnings
3916 and then Comes_From_Source (N)
3917 and then not In_Instance;
3918 -- This must be true for any of the optimization warnings, we
3919 -- clearly want to give them only for source with the flag on.
3920 -- We also skip these warnings in an instance since it may be
3921 -- the case that different instantiations have different ranges.
3923 Warn2 : constant Boolean :=
3925 and then Nkind (Original_Node (Rop)) = N_Range
3926 and then Is_Integer_Type (Etype (Lo));
3927 -- For the case where only one bound warning is elided, we also
3928 -- insist on an explicit range and an integer type. The reason is
3929 -- that the use of enumeration ranges including an end point is
3930 -- common, as is the use of a subtype name, one of whose bounds
3931 -- is the same as the type of the expression.
3934 -- If test is explicit x'first .. x'last, replace by valid check
3936 if Is_Scalar_Type (Ltyp)
3937 and then Nkind (Lo_Orig) = N_Attribute_Reference
3938 and then Attribute_Name (Lo_Orig) = Name_First
3939 and then Nkind (Prefix (Lo_Orig)) in N_Has_Entity
3940 and then Entity (Prefix (Lo_Orig)) = Ltyp
3941 and then Nkind (Hi_Orig) = N_Attribute_Reference
3942 and then Attribute_Name (Hi_Orig) = Name_Last
3943 and then Nkind (Prefix (Hi_Orig)) in N_Has_Entity
3944 and then Entity (Prefix (Hi_Orig)) = Ltyp
3945 and then Comes_From_Source (N)
3946 and then VM_Target = No_VM
3948 Substitute_Valid_Check;
3952 -- If bounds of type are known at compile time, and the end points
3953 -- are known at compile time and identical, this is another case
3954 -- for substituting a valid test. We only do this for discrete
3955 -- types, since it won't arise in practice for float types.
3957 if Comes_From_Source (N)
3958 and then Is_Discrete_Type (Ltyp)
3959 and then Compile_Time_Known_Value (Type_High_Bound (Ltyp))
3960 and then Compile_Time_Known_Value (Type_Low_Bound (Ltyp))
3961 and then Compile_Time_Known_Value (Lo)
3962 and then Compile_Time_Known_Value (Hi)
3963 and then Expr_Value (Type_High_Bound (Ltyp)) = Expr_Value (Hi)
3964 and then Expr_Value (Type_Low_Bound (Ltyp)) = Expr_Value (Lo)
3966 -- Kill warnings in instances, since they may be cases where we
3967 -- have a test in the generic that makes sense with some types
3968 -- and not with other types.
3970 and then not In_Instance
3972 Substitute_Valid_Check;
3976 -- If we have an explicit range, do a bit of optimization based
3977 -- on range analysis (we may be able to kill one or both checks).
3979 Lcheck := Compile_Time_Compare (Lop, Lo, Assume_Valid => False);
3980 Ucheck := Compile_Time_Compare (Lop, Hi, Assume_Valid => False);
3982 -- If either check is known to fail, replace result by False since
3983 -- the other check does not matter. Preserve the static flag for
3984 -- legality checks, because we are constant-folding beyond RM 4.9.
3986 if Lcheck = LT or else Ucheck = GT then
3988 Error_Msg_N ("?range test optimized away", N);
3989 Error_Msg_N ("\?value is known to be out of range", N);
3993 New_Reference_To (Standard_False, Loc));
3994 Analyze_And_Resolve (N, Rtyp);
3995 Set_Is_Static_Expression (N, Static);
3999 -- If both checks are known to succeed, replace result by True,
4000 -- since we know we are in range.
4002 elsif Lcheck in Compare_GE and then Ucheck in Compare_LE then
4004 Error_Msg_N ("?range test optimized away", N);
4005 Error_Msg_N ("\?value is known to be in range", N);
4009 New_Reference_To (Standard_True, Loc));
4010 Analyze_And_Resolve (N, Rtyp);
4011 Set_Is_Static_Expression (N, Static);
4015 -- If lower bound check succeeds and upper bound check is not
4016 -- known to succeed or fail, then replace the range check with
4017 -- a comparison against the upper bound.
4019 elsif Lcheck in Compare_GE then
4020 if Warn2 and then not In_Instance then
4021 Error_Msg_N ("?lower bound test optimized away", Lo);
4022 Error_Msg_N ("\?value is known to be in range", Lo);
4028 Right_Opnd => High_Bound (Rop)));
4029 Analyze_And_Resolve (N, Rtyp);
4033 -- If upper bound check succeeds and lower bound check is not
4034 -- known to succeed or fail, then replace the range check with
4035 -- a comparison against the lower bound.
4037 elsif Ucheck in Compare_LE then
4038 if Warn2 and then not In_Instance then
4039 Error_Msg_N ("?upper bound test optimized away", Hi);
4040 Error_Msg_N ("\?value is known to be in range", Hi);
4046 Right_Opnd => Low_Bound (Rop)));
4047 Analyze_And_Resolve (N, Rtyp);
4052 -- We couldn't optimize away the range check, but there is one
4053 -- more issue. If we are checking constant conditionals, then we
4054 -- see if we can determine the outcome assuming everything is
4055 -- valid, and if so give an appropriate warning.
4057 if Warn1 and then not Assume_No_Invalid_Values then
4058 Lcheck := Compile_Time_Compare (Lop, Lo, Assume_Valid => True);
4059 Ucheck := Compile_Time_Compare (Lop, Hi, Assume_Valid => True);
4061 -- Result is out of range for valid value
4063 if Lcheck = LT or else Ucheck = GT then
4065 ("?value can only be in range if it is invalid", N);
4067 -- Result is in range for valid value
4069 elsif Lcheck in Compare_GE and then Ucheck in Compare_LE then
4071 ("?value can only be out of range if it is invalid", N);
4073 -- Lower bound check succeeds if value is valid
4075 elsif Warn2 and then Lcheck in Compare_GE then
4077 ("?lower bound check only fails if it is invalid", Lo);
4079 -- Upper bound check succeeds if value is valid
4081 elsif Warn2 and then Ucheck in Compare_LE then
4083 ("?upper bound check only fails for invalid values", Hi);
4088 -- For all other cases of an explicit range, nothing to be done
4092 -- Here right operand is a subtype mark
4096 Typ : Entity_Id := Etype (Rop);
4097 Is_Acc : constant Boolean := Is_Access_Type (Typ);
4098 Obj : Node_Id := Lop;
4099 Cond : Node_Id := Empty;
4102 Remove_Side_Effects (Obj);
4104 -- For tagged type, do tagged membership operation
4106 if Is_Tagged_Type (Typ) then
4108 -- No expansion will be performed when VM_Target, as the VM
4109 -- back-ends will handle the membership tests directly (tags
4110 -- are not explicitly represented in Java objects, so the
4111 -- normal tagged membership expansion is not what we want).
4113 if VM_Target = No_VM then
4114 Rewrite (N, Tagged_Membership (N));
4115 Analyze_And_Resolve (N, Rtyp);
4120 -- If type is scalar type, rewrite as x in t'first .. t'last.
4121 -- This reason we do this is that the bounds may have the wrong
4122 -- type if they come from the original type definition. Also this
4123 -- way we get all the processing above for an explicit range.
4125 elsif Is_Scalar_Type (Typ) then
4129 Make_Attribute_Reference (Loc,
4130 Attribute_Name => Name_First,
4131 Prefix => New_Reference_To (Typ, Loc)),
4134 Make_Attribute_Reference (Loc,
4135 Attribute_Name => Name_Last,
4136 Prefix => New_Reference_To (Typ, Loc))));
4137 Analyze_And_Resolve (N, Rtyp);
4140 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
4141 -- a membership test if the subtype mark denotes a constrained
4142 -- Unchecked_Union subtype and the expression lacks inferable
4145 elsif Is_Unchecked_Union (Base_Type (Typ))
4146 and then Is_Constrained (Typ)
4147 and then not Has_Inferable_Discriminants (Lop)
4150 Make_Raise_Program_Error (Loc,
4151 Reason => PE_Unchecked_Union_Restriction));
4153 -- Prevent Gigi from generating incorrect code by rewriting
4154 -- the test as a standard False.
4157 New_Occurrence_Of (Standard_False, Loc));
4162 -- Here we have a non-scalar type
4165 Typ := Designated_Type (Typ);
4168 if not Is_Constrained (Typ) then
4170 New_Reference_To (Standard_True, Loc));
4171 Analyze_And_Resolve (N, Rtyp);
4173 -- For the constrained array case, we have to check the subscripts
4174 -- for an exact match if the lengths are non-zero (the lengths
4175 -- must match in any case).
4177 elsif Is_Array_Type (Typ) then
4179 Check_Subscripts : declare
4180 function Construct_Attribute_Reference
4183 Dim : Nat) return Node_Id;
4184 -- Build attribute reference E'Nam(Dim)
4186 -----------------------------------
4187 -- Construct_Attribute_Reference --
4188 -----------------------------------
4190 function Construct_Attribute_Reference
4193 Dim : Nat) return Node_Id
4197 Make_Attribute_Reference (Loc,
4199 Attribute_Name => Nam,
4200 Expressions => New_List (
4201 Make_Integer_Literal (Loc, Dim)));
4202 end Construct_Attribute_Reference;
4204 -- Start of processing for Check_Subscripts
4207 for J in 1 .. Number_Dimensions (Typ) loop
4208 Evolve_And_Then (Cond,
4211 Construct_Attribute_Reference
4212 (Duplicate_Subexpr_No_Checks (Obj),
4215 Construct_Attribute_Reference
4216 (New_Occurrence_Of (Typ, Loc), Name_First, J)));
4218 Evolve_And_Then (Cond,
4221 Construct_Attribute_Reference
4222 (Duplicate_Subexpr_No_Checks (Obj),
4225 Construct_Attribute_Reference
4226 (New_Occurrence_Of (Typ, Loc), Name_Last, J)));
4235 Right_Opnd => Make_Null (Loc)),
4236 Right_Opnd => Cond);
4240 Analyze_And_Resolve (N, Rtyp);
4241 end Check_Subscripts;
4243 -- These are the cases where constraint checks may be required,
4244 -- e.g. records with possible discriminants
4247 -- Expand the test into a series of discriminant comparisons.
4248 -- The expression that is built is the negation of the one that
4249 -- is used for checking discriminant constraints.
4251 Obj := Relocate_Node (Left_Opnd (N));
4253 if Has_Discriminants (Typ) then
4254 Cond := Make_Op_Not (Loc,
4255 Right_Opnd => Build_Discriminant_Checks (Obj, Typ));
4258 Cond := Make_Or_Else (Loc,
4262 Right_Opnd => Make_Null (Loc)),
4263 Right_Opnd => Cond);
4267 Cond := New_Occurrence_Of (Standard_True, Loc);
4271 Analyze_And_Resolve (N, Rtyp);
4277 --------------------------------
4278 -- Expand_N_Indexed_Component --
4279 --------------------------------
4281 procedure Expand_N_Indexed_Component (N : Node_Id) is
4282 Loc : constant Source_Ptr := Sloc (N);
4283 Typ : constant Entity_Id := Etype (N);
4284 P : constant Node_Id := Prefix (N);
4285 T : constant Entity_Id := Etype (P);
4288 -- A special optimization, if we have an indexed component that is
4289 -- selecting from a slice, then we can eliminate the slice, since, for
4290 -- example, x (i .. j)(k) is identical to x(k). The only difference is
4291 -- the range check required by the slice. The range check for the slice
4292 -- itself has already been generated. The range check for the
4293 -- subscripting operation is ensured by converting the subject to
4294 -- the subtype of the slice.
4296 -- This optimization not only generates better code, avoiding slice
4297 -- messing especially in the packed case, but more importantly bypasses
4298 -- some problems in handling this peculiar case, for example, the issue
4299 -- of dealing specially with object renamings.
4301 if Nkind (P) = N_Slice then
4303 Make_Indexed_Component (Loc,
4304 Prefix => Prefix (P),
4305 Expressions => New_List (
4307 (Etype (First_Index (Etype (P))),
4308 First (Expressions (N))))));
4309 Analyze_And_Resolve (N, Typ);
4313 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
4314 -- function, then additional actuals must be passed.
4316 if Ada_Version >= Ada_05
4317 and then Is_Build_In_Place_Function_Call (P)
4319 Make_Build_In_Place_Call_In_Anonymous_Context (P);
4322 -- If the prefix is an access type, then we unconditionally rewrite if
4323 -- as an explicit deference. This simplifies processing for several
4324 -- cases, including packed array cases and certain cases in which checks
4325 -- must be generated. We used to try to do this only when it was
4326 -- necessary, but it cleans up the code to do it all the time.
4328 if Is_Access_Type (T) then
4329 Insert_Explicit_Dereference (P);
4330 Analyze_And_Resolve (P, Designated_Type (T));
4333 -- Generate index and validity checks
4335 Generate_Index_Checks (N);
4337 if Validity_Checks_On and then Validity_Check_Subscripts then
4338 Apply_Subscript_Validity_Checks (N);
4341 -- All done for the non-packed case
4343 if not Is_Packed (Etype (Prefix (N))) then
4347 -- For packed arrays that are not bit-packed (i.e. the case of an array
4348 -- with one or more index types with a non-contiguous enumeration type),
4349 -- we can always use the normal packed element get circuit.
4351 if not Is_Bit_Packed_Array (Etype (Prefix (N))) then
4352 Expand_Packed_Element_Reference (N);
4356 -- For a reference to a component of a bit packed array, we have to
4357 -- convert it to a reference to the corresponding Packed_Array_Type.
4358 -- We only want to do this for simple references, and not for:
4360 -- Left side of assignment, or prefix of left side of assignment, or
4361 -- prefix of the prefix, to handle packed arrays of packed arrays,
4362 -- This case is handled in Exp_Ch5.Expand_N_Assignment_Statement
4364 -- Renaming objects in renaming associations
4365 -- This case is handled when a use of the renamed variable occurs
4367 -- Actual parameters for a procedure call
4368 -- This case is handled in Exp_Ch6.Expand_Actuals
4370 -- The second expression in a 'Read attribute reference
4372 -- The prefix of an address or size attribute reference
4374 -- The following circuit detects these exceptions
4377 Child : Node_Id := N;
4378 Parnt : Node_Id := Parent (N);
4382 if Nkind (Parnt) = N_Unchecked_Expression then
4385 elsif Nkind_In (Parnt, N_Object_Renaming_Declaration,
4386 N_Procedure_Call_Statement)
4387 or else (Nkind (Parnt) = N_Parameter_Association
4389 Nkind (Parent (Parnt)) = N_Procedure_Call_Statement)
4393 elsif Nkind (Parnt) = N_Attribute_Reference
4394 and then (Attribute_Name (Parnt) = Name_Address
4396 Attribute_Name (Parnt) = Name_Size)
4397 and then Prefix (Parnt) = Child
4401 elsif Nkind (Parnt) = N_Assignment_Statement
4402 and then Name (Parnt) = Child
4406 -- If the expression is an index of an indexed component, it must
4407 -- be expanded regardless of context.
4409 elsif Nkind (Parnt) = N_Indexed_Component
4410 and then Child /= Prefix (Parnt)
4412 Expand_Packed_Element_Reference (N);
4415 elsif Nkind (Parent (Parnt)) = N_Assignment_Statement
4416 and then Name (Parent (Parnt)) = Parnt
4420 elsif Nkind (Parnt) = N_Attribute_Reference
4421 and then Attribute_Name (Parnt) = Name_Read
4422 and then Next (First (Expressions (Parnt))) = Child
4426 elsif Nkind_In (Parnt, N_Indexed_Component, N_Selected_Component)
4427 and then Prefix (Parnt) = Child
4432 Expand_Packed_Element_Reference (N);
4436 -- Keep looking up tree for unchecked expression, or if we are the
4437 -- prefix of a possible assignment left side.
4440 Parnt := Parent (Child);
4443 end Expand_N_Indexed_Component;
4445 ---------------------
4446 -- Expand_N_Not_In --
4447 ---------------------
4449 -- Replace a not in b by not (a in b) so that the expansions for (a in b)
4450 -- can be done. This avoids needing to duplicate this expansion code.
4452 procedure Expand_N_Not_In (N : Node_Id) is
4453 Loc : constant Source_Ptr := Sloc (N);
4454 Typ : constant Entity_Id := Etype (N);
4455 Cfs : constant Boolean := Comes_From_Source (N);
4462 Left_Opnd => Left_Opnd (N),
4463 Right_Opnd => Right_Opnd (N))));
4465 -- We want this to appear as coming from source if original does (see
4466 -- transformations in Expand_N_In).
4468 Set_Comes_From_Source (N, Cfs);
4469 Set_Comes_From_Source (Right_Opnd (N), Cfs);
4471 -- Now analyze transformed node
4473 Analyze_And_Resolve (N, Typ);
4474 end Expand_N_Not_In;
4480 -- The only replacement required is for the case of a null of type that is
4481 -- an access to protected subprogram. We represent such access values as a
4482 -- record, and so we must replace the occurrence of null by the equivalent
4483 -- record (with a null address and a null pointer in it), so that the
4484 -- backend creates the proper value.
4486 procedure Expand_N_Null (N : Node_Id) is
4487 Loc : constant Source_Ptr := Sloc (N);
4488 Typ : constant Entity_Id := Etype (N);
4492 if Is_Access_Protected_Subprogram_Type (Typ) then
4494 Make_Aggregate (Loc,
4495 Expressions => New_List (
4496 New_Occurrence_Of (RTE (RE_Null_Address), Loc),
4500 Analyze_And_Resolve (N, Equivalent_Type (Typ));
4502 -- For subsequent semantic analysis, the node must retain its type.
4503 -- Gigi in any case replaces this type by the corresponding record
4504 -- type before processing the node.
4510 when RE_Not_Available =>
4514 ---------------------
4515 -- Expand_N_Op_Abs --
4516 ---------------------
4518 procedure Expand_N_Op_Abs (N : Node_Id) is
4519 Loc : constant Source_Ptr := Sloc (N);
4520 Expr : constant Node_Id := Right_Opnd (N);
4523 Unary_Op_Validity_Checks (N);
4525 -- Deal with software overflow checking
4527 if not Backend_Overflow_Checks_On_Target
4528 and then Is_Signed_Integer_Type (Etype (N))
4529 and then Do_Overflow_Check (N)
4531 -- The only case to worry about is when the argument is equal to the
4532 -- largest negative number, so what we do is to insert the check:
4534 -- [constraint_error when Expr = typ'Base'First]
4536 -- with the usual Duplicate_Subexpr use coding for expr
4539 Make_Raise_Constraint_Error (Loc,
4542 Left_Opnd => Duplicate_Subexpr (Expr),
4544 Make_Attribute_Reference (Loc,
4546 New_Occurrence_Of (Base_Type (Etype (Expr)), Loc),
4547 Attribute_Name => Name_First)),
4548 Reason => CE_Overflow_Check_Failed));
4551 -- Vax floating-point types case
4553 if Vax_Float (Etype (N)) then
4554 Expand_Vax_Arith (N);
4556 end Expand_N_Op_Abs;
4558 ---------------------
4559 -- Expand_N_Op_Add --
4560 ---------------------
4562 procedure Expand_N_Op_Add (N : Node_Id) is
4563 Typ : constant Entity_Id := Etype (N);
4566 Binary_Op_Validity_Checks (N);
4568 -- N + 0 = 0 + N = N for integer types
4570 if Is_Integer_Type (Typ) then
4571 if Compile_Time_Known_Value (Right_Opnd (N))
4572 and then Expr_Value (Right_Opnd (N)) = Uint_0
4574 Rewrite (N, Left_Opnd (N));
4577 elsif Compile_Time_Known_Value (Left_Opnd (N))
4578 and then Expr_Value (Left_Opnd (N)) = Uint_0
4580 Rewrite (N, Right_Opnd (N));
4585 -- Arithmetic overflow checks for signed integer/fixed point types
4587 if Is_Signed_Integer_Type (Typ)
4588 or else Is_Fixed_Point_Type (Typ)
4590 Apply_Arithmetic_Overflow_Check (N);
4593 -- Vax floating-point types case
4595 elsif Vax_Float (Typ) then
4596 Expand_Vax_Arith (N);
4598 end Expand_N_Op_Add;
4600 ---------------------
4601 -- Expand_N_Op_And --
4602 ---------------------
4604 procedure Expand_N_Op_And (N : Node_Id) is
4605 Typ : constant Entity_Id := Etype (N);
4608 Binary_Op_Validity_Checks (N);
4610 if Is_Array_Type (Etype (N)) then
4611 Expand_Boolean_Operator (N);
4613 elsif Is_Boolean_Type (Etype (N)) then
4614 Adjust_Condition (Left_Opnd (N));
4615 Adjust_Condition (Right_Opnd (N));
4616 Set_Etype (N, Standard_Boolean);
4617 Adjust_Result_Type (N, Typ);
4619 end Expand_N_Op_And;
4621 ------------------------
4622 -- Expand_N_Op_Concat --
4623 ------------------------
4625 procedure Expand_N_Op_Concat (N : Node_Id) is
4627 -- List of operands to be concatenated
4630 -- Node which is to be replaced by the result of concatenating the nodes
4631 -- in the list Opnds.
4634 -- Ensure validity of both operands
4636 Binary_Op_Validity_Checks (N);
4638 -- If we are the left operand of a concatenation higher up the tree,
4639 -- then do nothing for now, since we want to deal with a series of
4640 -- concatenations as a unit.
4642 if Nkind (Parent (N)) = N_Op_Concat
4643 and then N = Left_Opnd (Parent (N))
4648 -- We get here with a concatenation whose left operand may be a
4649 -- concatenation itself with a consistent type. We need to process
4650 -- these concatenation operands from left to right, which means
4651 -- from the deepest node in the tree to the highest node.
4654 while Nkind (Left_Opnd (Cnode)) = N_Op_Concat loop
4655 Cnode := Left_Opnd (Cnode);
4658 -- Now Opnd is the deepest Opnd, and its parents are the concatenation
4659 -- nodes above, so now we process bottom up, doing the operations. We
4660 -- gather a string that is as long as possible up to five operands
4662 -- The outer loop runs more than once if more than one concatenation
4663 -- type is involved.
4666 Opnds := New_List (Left_Opnd (Cnode), Right_Opnd (Cnode));
4667 Set_Parent (Opnds, N);
4669 -- The inner loop gathers concatenation operands
4671 Inner : while Cnode /= N
4672 and then Base_Type (Etype (Cnode)) =
4673 Base_Type (Etype (Parent (Cnode)))
4675 Cnode := Parent (Cnode);
4676 Append (Right_Opnd (Cnode), Opnds);
4679 Expand_Concatenate (Cnode, Opnds);
4681 exit Outer when Cnode = N;
4682 Cnode := Parent (Cnode);
4684 end Expand_N_Op_Concat;
4686 ------------------------
4687 -- Expand_N_Op_Divide --
4688 ------------------------
4690 procedure Expand_N_Op_Divide (N : Node_Id) is
4691 Loc : constant Source_Ptr := Sloc (N);
4692 Lopnd : constant Node_Id := Left_Opnd (N);
4693 Ropnd : constant Node_Id := Right_Opnd (N);
4694 Ltyp : constant Entity_Id := Etype (Lopnd);
4695 Rtyp : constant Entity_Id := Etype (Ropnd);
4696 Typ : Entity_Id := Etype (N);
4697 Rknow : constant Boolean := Is_Integer_Type (Typ)
4699 Compile_Time_Known_Value (Ropnd);
4703 Binary_Op_Validity_Checks (N);
4706 Rval := Expr_Value (Ropnd);
4709 -- N / 1 = N for integer types
4711 if Rknow and then Rval = Uint_1 then
4716 -- Convert x / 2 ** y to Shift_Right (x, y). Note that the fact that
4717 -- Is_Power_Of_2_For_Shift is set means that we know that our left
4718 -- operand is an unsigned integer, as required for this to work.
4720 if Nkind (Ropnd) = N_Op_Expon
4721 and then Is_Power_Of_2_For_Shift (Ropnd)
4723 -- We cannot do this transformation in configurable run time mode if we
4724 -- have 64-bit -- integers and long shifts are not available.
4728 or else Support_Long_Shifts_On_Target)
4731 Make_Op_Shift_Right (Loc,
4734 Convert_To (Standard_Natural, Right_Opnd (Ropnd))));
4735 Analyze_And_Resolve (N, Typ);
4739 -- Do required fixup of universal fixed operation
4741 if Typ = Universal_Fixed then
4742 Fixup_Universal_Fixed_Operation (N);
4746 -- Divisions with fixed-point results
4748 if Is_Fixed_Point_Type (Typ) then
4750 -- No special processing if Treat_Fixed_As_Integer is set, since
4751 -- from a semantic point of view such operations are simply integer
4752 -- operations and will be treated that way.
4754 if not Treat_Fixed_As_Integer (N) then
4755 if Is_Integer_Type (Rtyp) then
4756 Expand_Divide_Fixed_By_Integer_Giving_Fixed (N);
4758 Expand_Divide_Fixed_By_Fixed_Giving_Fixed (N);
4762 -- Other cases of division of fixed-point operands. Again we exclude the
4763 -- case where Treat_Fixed_As_Integer is set.
4765 elsif (Is_Fixed_Point_Type (Ltyp) or else
4766 Is_Fixed_Point_Type (Rtyp))
4767 and then not Treat_Fixed_As_Integer (N)
4769 if Is_Integer_Type (Typ) then
4770 Expand_Divide_Fixed_By_Fixed_Giving_Integer (N);
4772 pragma Assert (Is_Floating_Point_Type (Typ));
4773 Expand_Divide_Fixed_By_Fixed_Giving_Float (N);
4776 -- Mixed-mode operations can appear in a non-static universal context,
4777 -- in which case the integer argument must be converted explicitly.
4779 elsif Typ = Universal_Real
4780 and then Is_Integer_Type (Rtyp)
4783 Convert_To (Universal_Real, Relocate_Node (Ropnd)));
4785 Analyze_And_Resolve (Ropnd, Universal_Real);
4787 elsif Typ = Universal_Real
4788 and then Is_Integer_Type (Ltyp)
4791 Convert_To (Universal_Real, Relocate_Node (Lopnd)));
4793 Analyze_And_Resolve (Lopnd, Universal_Real);
4795 -- Non-fixed point cases, do integer zero divide and overflow checks
4797 elsif Is_Integer_Type (Typ) then
4798 Apply_Divide_Check (N);
4800 -- Check for 64-bit division available, or long shifts if the divisor
4801 -- is a small power of 2 (since such divides will be converted into
4804 if Esize (Ltyp) > 32
4805 and then not Support_64_Bit_Divides_On_Target
4808 or else not Support_Long_Shifts_On_Target
4809 or else (Rval /= Uint_2 and then
4810 Rval /= Uint_4 and then
4811 Rval /= Uint_8 and then
4812 Rval /= Uint_16 and then
4813 Rval /= Uint_32 and then
4816 Error_Msg_CRT ("64-bit division", N);
4819 -- Deal with Vax_Float
4821 elsif Vax_Float (Typ) then
4822 Expand_Vax_Arith (N);
4825 end Expand_N_Op_Divide;
4827 --------------------
4828 -- Expand_N_Op_Eq --
4829 --------------------
4831 procedure Expand_N_Op_Eq (N : Node_Id) is
4832 Loc : constant Source_Ptr := Sloc (N);
4833 Typ : constant Entity_Id := Etype (N);
4834 Lhs : constant Node_Id := Left_Opnd (N);
4835 Rhs : constant Node_Id := Right_Opnd (N);
4836 Bodies : constant List_Id := New_List;
4837 A_Typ : constant Entity_Id := Etype (Lhs);
4839 Typl : Entity_Id := A_Typ;
4840 Op_Name : Entity_Id;
4843 procedure Build_Equality_Call (Eq : Entity_Id);
4844 -- If a constructed equality exists for the type or for its parent,
4845 -- build and analyze call, adding conversions if the operation is
4848 function Has_Unconstrained_UU_Component (Typ : Node_Id) return Boolean;
4849 -- Determines whether a type has a subcomponent of an unconstrained
4850 -- Unchecked_Union subtype. Typ is a record type.
4852 -------------------------
4853 -- Build_Equality_Call --
4854 -------------------------
4856 procedure Build_Equality_Call (Eq : Entity_Id) is
4857 Op_Type : constant Entity_Id := Etype (First_Formal (Eq));
4858 L_Exp : Node_Id := Relocate_Node (Lhs);
4859 R_Exp : Node_Id := Relocate_Node (Rhs);
4862 if Base_Type (Op_Type) /= Base_Type (A_Typ)
4863 and then not Is_Class_Wide_Type (A_Typ)
4865 L_Exp := OK_Convert_To (Op_Type, L_Exp);
4866 R_Exp := OK_Convert_To (Op_Type, R_Exp);
4869 -- If we have an Unchecked_Union, we need to add the inferred
4870 -- discriminant values as actuals in the function call. At this
4871 -- point, the expansion has determined that both operands have
4872 -- inferable discriminants.
4874 if Is_Unchecked_Union (Op_Type) then
4876 Lhs_Type : constant Node_Id := Etype (L_Exp);
4877 Rhs_Type : constant Node_Id := Etype (R_Exp);
4878 Lhs_Discr_Val : Node_Id;
4879 Rhs_Discr_Val : Node_Id;
4882 -- Per-object constrained selected components require special
4883 -- attention. If the enclosing scope of the component is an
4884 -- Unchecked_Union, we cannot reference its discriminants
4885 -- directly. This is why we use the two extra parameters of
4886 -- the equality function of the enclosing Unchecked_Union.
4888 -- type UU_Type (Discr : Integer := 0) is
4891 -- pragma Unchecked_Union (UU_Type);
4893 -- 1. Unchecked_Union enclosing record:
4895 -- type Enclosing_UU_Type (Discr : Integer := 0) is record
4897 -- Comp : UU_Type (Discr);
4899 -- end Enclosing_UU_Type;
4900 -- pragma Unchecked_Union (Enclosing_UU_Type);
4902 -- Obj1 : Enclosing_UU_Type;
4903 -- Obj2 : Enclosing_UU_Type (1);
4905 -- [. . .] Obj1 = Obj2 [. . .]
4909 -- if not (uu_typeEQ (obj1.comp, obj2.comp, a, b)) then
4911 -- A and B are the formal parameters of the equality function
4912 -- of Enclosing_UU_Type. The function always has two extra
4913 -- formals to capture the inferred discriminant values.
4915 -- 2. Non-Unchecked_Union enclosing record:
4918 -- Enclosing_Non_UU_Type (Discr : Integer := 0)
4921 -- Comp : UU_Type (Discr);
4923 -- end Enclosing_Non_UU_Type;
4925 -- Obj1 : Enclosing_Non_UU_Type;
4926 -- Obj2 : Enclosing_Non_UU_Type (1);
4928 -- ... Obj1 = Obj2 ...
4932 -- if not (uu_typeEQ (obj1.comp, obj2.comp,
4933 -- obj1.discr, obj2.discr)) then
4935 -- In this case we can directly reference the discriminants of
4936 -- the enclosing record.
4940 if Nkind (Lhs) = N_Selected_Component
4941 and then Has_Per_Object_Constraint
4942 (Entity (Selector_Name (Lhs)))
4944 -- Enclosing record is an Unchecked_Union, use formal A
4946 if Is_Unchecked_Union (Scope
4947 (Entity (Selector_Name (Lhs))))
4950 Make_Identifier (Loc,
4953 -- Enclosing record is of a non-Unchecked_Union type, it is
4954 -- possible to reference the discriminant.
4958 Make_Selected_Component (Loc,
4959 Prefix => Prefix (Lhs),
4962 (Get_Discriminant_Value
4963 (First_Discriminant (Lhs_Type),
4965 Stored_Constraint (Lhs_Type))));
4968 -- Comment needed here ???
4971 -- Infer the discriminant value
4975 (Get_Discriminant_Value
4976 (First_Discriminant (Lhs_Type),
4978 Stored_Constraint (Lhs_Type)));
4983 if Nkind (Rhs) = N_Selected_Component
4984 and then Has_Per_Object_Constraint
4985 (Entity (Selector_Name (Rhs)))
4987 if Is_Unchecked_Union
4988 (Scope (Entity (Selector_Name (Rhs))))
4991 Make_Identifier (Loc,
4996 Make_Selected_Component (Loc,
4997 Prefix => Prefix (Rhs),
4999 New_Copy (Get_Discriminant_Value (
5000 First_Discriminant (Rhs_Type),
5002 Stored_Constraint (Rhs_Type))));
5007 New_Copy (Get_Discriminant_Value (
5008 First_Discriminant (Rhs_Type),
5010 Stored_Constraint (Rhs_Type)));
5015 Make_Function_Call (Loc,
5016 Name => New_Reference_To (Eq, Loc),
5017 Parameter_Associations => New_List (
5024 -- Normal case, not an unchecked union
5028 Make_Function_Call (Loc,
5029 Name => New_Reference_To (Eq, Loc),
5030 Parameter_Associations => New_List (L_Exp, R_Exp)));
5033 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
5034 end Build_Equality_Call;
5036 ------------------------------------
5037 -- Has_Unconstrained_UU_Component --
5038 ------------------------------------
5040 function Has_Unconstrained_UU_Component
5041 (Typ : Node_Id) return Boolean
5043 Tdef : constant Node_Id :=
5044 Type_Definition (Declaration_Node (Base_Type (Typ)));
5048 function Component_Is_Unconstrained_UU
5049 (Comp : Node_Id) return Boolean;
5050 -- Determines whether the subtype of the component is an
5051 -- unconstrained Unchecked_Union.
5053 function Variant_Is_Unconstrained_UU
5054 (Variant : Node_Id) return Boolean;
5055 -- Determines whether a component of the variant has an unconstrained
5056 -- Unchecked_Union subtype.
5058 -----------------------------------
5059 -- Component_Is_Unconstrained_UU --
5060 -----------------------------------
5062 function Component_Is_Unconstrained_UU
5063 (Comp : Node_Id) return Boolean
5066 if Nkind (Comp) /= N_Component_Declaration then
5071 Sindic : constant Node_Id :=
5072 Subtype_Indication (Component_Definition (Comp));
5075 -- Unconstrained nominal type. In the case of a constraint
5076 -- present, the node kind would have been N_Subtype_Indication.
5078 if Nkind (Sindic) = N_Identifier then
5079 return Is_Unchecked_Union (Base_Type (Etype (Sindic)));
5084 end Component_Is_Unconstrained_UU;
5086 ---------------------------------
5087 -- Variant_Is_Unconstrained_UU --
5088 ---------------------------------
5090 function Variant_Is_Unconstrained_UU
5091 (Variant : Node_Id) return Boolean
5093 Clist : constant Node_Id := Component_List (Variant);
5096 if Is_Empty_List (Component_Items (Clist)) then
5100 -- We only need to test one component
5103 Comp : Node_Id := First (Component_Items (Clist));
5106 while Present (Comp) loop
5107 if Component_Is_Unconstrained_UU (Comp) then
5115 -- None of the components withing the variant were of
5116 -- unconstrained Unchecked_Union type.
5119 end Variant_Is_Unconstrained_UU;
5121 -- Start of processing for Has_Unconstrained_UU_Component
5124 if Null_Present (Tdef) then
5128 Clist := Component_List (Tdef);
5129 Vpart := Variant_Part (Clist);
5131 -- Inspect available components
5133 if Present (Component_Items (Clist)) then
5135 Comp : Node_Id := First (Component_Items (Clist));
5138 while Present (Comp) loop
5140 -- One component is sufficient
5142 if Component_Is_Unconstrained_UU (Comp) then
5151 -- Inspect available components withing variants
5153 if Present (Vpart) then
5155 Variant : Node_Id := First (Variants (Vpart));
5158 while Present (Variant) loop
5160 -- One component within a variant is sufficient
5162 if Variant_Is_Unconstrained_UU (Variant) then
5171 -- Neither the available components, nor the components inside the
5172 -- variant parts were of an unconstrained Unchecked_Union subtype.
5175 end Has_Unconstrained_UU_Component;
5177 -- Start of processing for Expand_N_Op_Eq
5180 Binary_Op_Validity_Checks (N);
5182 if Ekind (Typl) = E_Private_Type then
5183 Typl := Underlying_Type (Typl);
5184 elsif Ekind (Typl) = E_Private_Subtype then
5185 Typl := Underlying_Type (Base_Type (Typl));
5190 -- It may happen in error situations that the underlying type is not
5191 -- set. The error will be detected later, here we just defend the
5198 Typl := Base_Type (Typl);
5200 -- Boolean types (requiring handling of non-standard case)
5202 if Is_Boolean_Type (Typl) then
5203 Adjust_Condition (Left_Opnd (N));
5204 Adjust_Condition (Right_Opnd (N));
5205 Set_Etype (N, Standard_Boolean);
5206 Adjust_Result_Type (N, Typ);
5210 elsif Is_Array_Type (Typl) then
5212 -- If we are doing full validity checking, and it is possible for the
5213 -- array elements to be invalid then expand out array comparisons to
5214 -- make sure that we check the array elements.
5216 if Validity_Check_Operands
5217 and then not Is_Known_Valid (Component_Type (Typl))
5220 Save_Force_Validity_Checks : constant Boolean :=
5221 Force_Validity_Checks;
5223 Force_Validity_Checks := True;
5225 Expand_Array_Equality
5227 Relocate_Node (Lhs),
5228 Relocate_Node (Rhs),
5231 Insert_Actions (N, Bodies);
5232 Analyze_And_Resolve (N, Standard_Boolean);
5233 Force_Validity_Checks := Save_Force_Validity_Checks;
5236 -- Packed case where both operands are known aligned
5238 elsif Is_Bit_Packed_Array (Typl)
5239 and then not Is_Possibly_Unaligned_Object (Lhs)
5240 and then not Is_Possibly_Unaligned_Object (Rhs)
5242 Expand_Packed_Eq (N);
5244 -- Where the component type is elementary we can use a block bit
5245 -- comparison (if supported on the target) exception in the case
5246 -- of floating-point (negative zero issues require element by
5247 -- element comparison), and atomic types (where we must be sure
5248 -- to load elements independently) and possibly unaligned arrays.
5250 elsif Is_Elementary_Type (Component_Type (Typl))
5251 and then not Is_Floating_Point_Type (Component_Type (Typl))
5252 and then not Is_Atomic (Component_Type (Typl))
5253 and then not Is_Possibly_Unaligned_Object (Lhs)
5254 and then not Is_Possibly_Unaligned_Object (Rhs)
5255 and then Support_Composite_Compare_On_Target
5259 -- For composite and floating-point cases, expand equality loop to
5260 -- make sure of using proper comparisons for tagged types, and
5261 -- correctly handling the floating-point case.
5265 Expand_Array_Equality
5267 Relocate_Node (Lhs),
5268 Relocate_Node (Rhs),
5271 Insert_Actions (N, Bodies, Suppress => All_Checks);
5272 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
5277 elsif Is_Record_Type (Typl) then
5279 -- For tagged types, use the primitive "="
5281 if Is_Tagged_Type (Typl) then
5283 -- No need to do anything else compiling under restriction
5284 -- No_Dispatching_Calls. During the semantic analysis we
5285 -- already notified such violation.
5287 if Restriction_Active (No_Dispatching_Calls) then
5291 -- If this is derived from an untagged private type completed with
5292 -- a tagged type, it does not have a full view, so we use the
5293 -- primitive operations of the private type. This check should no
5294 -- longer be necessary when these types get their full views???
5296 if Is_Private_Type (A_Typ)
5297 and then not Is_Tagged_Type (A_Typ)
5298 and then Is_Derived_Type (A_Typ)
5299 and then No (Full_View (A_Typ))
5301 -- Search for equality operation, checking that the operands
5302 -- have the same type. Note that we must find a matching entry,
5303 -- or something is very wrong!
5305 Prim := First_Elmt (Collect_Primitive_Operations (A_Typ));
5307 while Present (Prim) loop
5308 exit when Chars (Node (Prim)) = Name_Op_Eq
5309 and then Etype (First_Formal (Node (Prim))) =
5310 Etype (Next_Formal (First_Formal (Node (Prim))))
5312 Base_Type (Etype (Node (Prim))) = Standard_Boolean;
5317 pragma Assert (Present (Prim));
5318 Op_Name := Node (Prim);
5320 -- Find the type's predefined equality or an overriding
5321 -- user- defined equality. The reason for not simply calling
5322 -- Find_Prim_Op here is that there may be a user-defined
5323 -- overloaded equality op that precedes the equality that we want,
5324 -- so we have to explicitly search (e.g., there could be an
5325 -- equality with two different parameter types).
5328 if Is_Class_Wide_Type (Typl) then
5329 Typl := Root_Type (Typl);
5332 Prim := First_Elmt (Primitive_Operations (Typl));
5333 while Present (Prim) loop
5334 exit when Chars (Node (Prim)) = Name_Op_Eq
5335 and then Etype (First_Formal (Node (Prim))) =
5336 Etype (Next_Formal (First_Formal (Node (Prim))))
5338 Base_Type (Etype (Node (Prim))) = Standard_Boolean;
5343 pragma Assert (Present (Prim));
5344 Op_Name := Node (Prim);
5347 Build_Equality_Call (Op_Name);
5349 -- Ada 2005 (AI-216): Program_Error is raised when evaluating the
5350 -- predefined equality operator for a type which has a subcomponent
5351 -- of an Unchecked_Union type whose nominal subtype is unconstrained.
5353 elsif Has_Unconstrained_UU_Component (Typl) then
5355 Make_Raise_Program_Error (Loc,
5356 Reason => PE_Unchecked_Union_Restriction));
5358 -- Prevent Gigi from generating incorrect code by rewriting the
5359 -- equality as a standard False.
5362 New_Occurrence_Of (Standard_False, Loc));
5364 elsif Is_Unchecked_Union (Typl) then
5366 -- If we can infer the discriminants of the operands, we make a
5367 -- call to the TSS equality function.
5369 if Has_Inferable_Discriminants (Lhs)
5371 Has_Inferable_Discriminants (Rhs)
5374 (TSS (Root_Type (Typl), TSS_Composite_Equality));
5377 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
5378 -- the predefined equality operator for an Unchecked_Union type
5379 -- if either of the operands lack inferable discriminants.
5382 Make_Raise_Program_Error (Loc,
5383 Reason => PE_Unchecked_Union_Restriction));
5385 -- Prevent Gigi from generating incorrect code by rewriting
5386 -- the equality as a standard False.
5389 New_Occurrence_Of (Standard_False, Loc));
5393 -- If a type support function is present (for complex cases), use it
5395 elsif Present (TSS (Root_Type (Typl), TSS_Composite_Equality)) then
5397 (TSS (Root_Type (Typl), TSS_Composite_Equality));
5399 -- Otherwise expand the component by component equality. Note that
5400 -- we never use block-bit comparisons for records, because of the
5401 -- problems with gaps. The backend will often be able to recombine
5402 -- the separate comparisons that we generate here.
5405 Remove_Side_Effects (Lhs);
5406 Remove_Side_Effects (Rhs);
5408 Expand_Record_Equality (N, Typl, Lhs, Rhs, Bodies));
5410 Insert_Actions (N, Bodies, Suppress => All_Checks);
5411 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
5415 -- Test if result is known at compile time
5417 Rewrite_Comparison (N);
5419 -- If we still have comparison for Vax_Float, process it
5421 if Vax_Float (Typl) and then Nkind (N) in N_Op_Compare then
5422 Expand_Vax_Comparison (N);
5427 -----------------------
5428 -- Expand_N_Op_Expon --
5429 -----------------------
5431 procedure Expand_N_Op_Expon (N : Node_Id) is
5432 Loc : constant Source_Ptr := Sloc (N);
5433 Typ : constant Entity_Id := Etype (N);
5434 Rtyp : constant Entity_Id := Root_Type (Typ);
5435 Base : constant Node_Id := Relocate_Node (Left_Opnd (N));
5436 Bastyp : constant Node_Id := Etype (Base);
5437 Exp : constant Node_Id := Relocate_Node (Right_Opnd (N));
5438 Exptyp : constant Entity_Id := Etype (Exp);
5439 Ovflo : constant Boolean := Do_Overflow_Check (N);
5448 Binary_Op_Validity_Checks (N);
5450 -- If either operand is of a private type, then we have the use of an
5451 -- intrinsic operator, and we get rid of the privateness, by using root
5452 -- types of underlying types for the actual operation. Otherwise the
5453 -- private types will cause trouble if we expand multiplications or
5454 -- shifts etc. We also do this transformation if the result type is
5455 -- different from the base type.
5457 if Is_Private_Type (Etype (Base))
5459 Is_Private_Type (Typ)
5461 Is_Private_Type (Exptyp)
5463 Rtyp /= Root_Type (Bastyp)
5466 Bt : constant Entity_Id := Root_Type (Underlying_Type (Bastyp));
5467 Et : constant Entity_Id := Root_Type (Underlying_Type (Exptyp));
5471 Unchecked_Convert_To (Typ,
5473 Left_Opnd => Unchecked_Convert_To (Bt, Base),
5474 Right_Opnd => Unchecked_Convert_To (Et, Exp))));
5475 Analyze_And_Resolve (N, Typ);
5480 -- Test for case of known right argument
5482 if Compile_Time_Known_Value (Exp) then
5483 Expv := Expr_Value (Exp);
5485 -- We only fold small non-negative exponents. You might think we
5486 -- could fold small negative exponents for the real case, but we
5487 -- can't because we are required to raise Constraint_Error for
5488 -- the case of 0.0 ** (negative) even if Machine_Overflows = False.
5489 -- See ACVC test C4A012B.
5491 if Expv >= 0 and then Expv <= 4 then
5493 -- X ** 0 = 1 (or 1.0)
5497 -- Call Remove_Side_Effects to ensure that any side effects
5498 -- in the ignored left operand (in particular function calls
5499 -- to user defined functions) are properly executed.
5501 Remove_Side_Effects (Base);
5503 if Ekind (Typ) in Integer_Kind then
5504 Xnode := Make_Integer_Literal (Loc, Intval => 1);
5506 Xnode := Make_Real_Literal (Loc, Ureal_1);
5518 Make_Op_Multiply (Loc,
5519 Left_Opnd => Duplicate_Subexpr (Base),
5520 Right_Opnd => Duplicate_Subexpr_No_Checks (Base));
5522 -- X ** 3 = X * X * X
5526 Make_Op_Multiply (Loc,
5528 Make_Op_Multiply (Loc,
5529 Left_Opnd => Duplicate_Subexpr (Base),
5530 Right_Opnd => Duplicate_Subexpr_No_Checks (Base)),
5531 Right_Opnd => Duplicate_Subexpr_No_Checks (Base));
5534 -- En : constant base'type := base * base;
5540 Make_Defining_Identifier (Loc, New_Internal_Name ('E'));
5542 Insert_Actions (N, New_List (
5543 Make_Object_Declaration (Loc,
5544 Defining_Identifier => Temp,
5545 Constant_Present => True,
5546 Object_Definition => New_Reference_To (Typ, Loc),
5548 Make_Op_Multiply (Loc,
5549 Left_Opnd => Duplicate_Subexpr (Base),
5550 Right_Opnd => Duplicate_Subexpr_No_Checks (Base)))));
5553 Make_Op_Multiply (Loc,
5554 Left_Opnd => New_Reference_To (Temp, Loc),
5555 Right_Opnd => New_Reference_To (Temp, Loc));
5559 Analyze_And_Resolve (N, Typ);
5564 -- Case of (2 ** expression) appearing as an argument of an integer
5565 -- multiplication, or as the right argument of a division of a non-
5566 -- negative integer. In such cases we leave the node untouched, setting
5567 -- the flag Is_Natural_Power_Of_2_for_Shift set, then the expansion
5568 -- of the higher level node converts it into a shift.
5570 -- Note: this transformation is not applicable for a modular type with
5571 -- a non-binary modulus in the multiplication case, since we get a wrong
5572 -- result if the shift causes an overflow before the modular reduction.
5574 if Nkind (Base) = N_Integer_Literal
5575 and then Intval (Base) = 2
5576 and then Is_Integer_Type (Root_Type (Exptyp))
5577 and then Esize (Root_Type (Exptyp)) <= Esize (Standard_Integer)
5578 and then Is_Unsigned_Type (Exptyp)
5580 and then Nkind (Parent (N)) in N_Binary_Op
5583 P : constant Node_Id := Parent (N);
5584 L : constant Node_Id := Left_Opnd (P);
5585 R : constant Node_Id := Right_Opnd (P);
5588 if (Nkind (P) = N_Op_Multiply
5589 and then not Non_Binary_Modulus (Typ)
5591 ((Is_Integer_Type (Etype (L)) and then R = N)
5593 (Is_Integer_Type (Etype (R)) and then L = N))
5594 and then not Do_Overflow_Check (P))
5597 (Nkind (P) = N_Op_Divide
5598 and then Is_Integer_Type (Etype (L))
5599 and then Is_Unsigned_Type (Etype (L))
5601 and then not Do_Overflow_Check (P))
5603 Set_Is_Power_Of_2_For_Shift (N);
5609 -- Fall through if exponentiation must be done using a runtime routine
5611 -- First deal with modular case
5613 if Is_Modular_Integer_Type (Rtyp) then
5615 -- Non-binary case, we call the special exponentiation routine for
5616 -- the non-binary case, converting the argument to Long_Long_Integer
5617 -- and passing the modulus value. Then the result is converted back
5618 -- to the base type.
5620 if Non_Binary_Modulus (Rtyp) then
5623 Make_Function_Call (Loc,
5624 Name => New_Reference_To (RTE (RE_Exp_Modular), Loc),
5625 Parameter_Associations => New_List (
5626 Convert_To (Standard_Integer, Base),
5627 Make_Integer_Literal (Loc, Modulus (Rtyp)),
5630 -- Binary case, in this case, we call one of two routines, either the
5631 -- unsigned integer case, or the unsigned long long integer case,
5632 -- with a final "and" operation to do the required mod.
5635 if UI_To_Int (Esize (Rtyp)) <= Standard_Integer_Size then
5636 Ent := RTE (RE_Exp_Unsigned);
5638 Ent := RTE (RE_Exp_Long_Long_Unsigned);
5645 Make_Function_Call (Loc,
5646 Name => New_Reference_To (Ent, Loc),
5647 Parameter_Associations => New_List (
5648 Convert_To (Etype (First_Formal (Ent)), Base),
5651 Make_Integer_Literal (Loc, Modulus (Rtyp) - 1))));
5655 -- Common exit point for modular type case
5657 Analyze_And_Resolve (N, Typ);
5660 -- Signed integer cases, done using either Integer or Long_Long_Integer.
5661 -- It is not worth having routines for Short_[Short_]Integer, since for
5662 -- most machines it would not help, and it would generate more code that
5663 -- might need certification when a certified run time is required.
5665 -- In the integer cases, we have two routines, one for when overflow
5666 -- checks are required, and one when they are not required, since there
5667 -- is a real gain in omitting checks on many machines.
5669 elsif Rtyp = Base_Type (Standard_Long_Long_Integer)
5670 or else (Rtyp = Base_Type (Standard_Long_Integer)
5672 Esize (Standard_Long_Integer) > Esize (Standard_Integer))
5673 or else (Rtyp = Universal_Integer)
5675 Etyp := Standard_Long_Long_Integer;
5678 Rent := RE_Exp_Long_Long_Integer;
5680 Rent := RE_Exn_Long_Long_Integer;
5683 elsif Is_Signed_Integer_Type (Rtyp) then
5684 Etyp := Standard_Integer;
5687 Rent := RE_Exp_Integer;
5689 Rent := RE_Exn_Integer;
5692 -- Floating-point cases, always done using Long_Long_Float. We do not
5693 -- need separate routines for the overflow case here, since in the case
5694 -- of floating-point, we generate infinities anyway as a rule (either
5695 -- that or we automatically trap overflow), and if there is an infinity
5696 -- generated and a range check is required, the check will fail anyway.
5699 pragma Assert (Is_Floating_Point_Type (Rtyp));
5700 Etyp := Standard_Long_Long_Float;
5701 Rent := RE_Exn_Long_Long_Float;
5704 -- Common processing for integer cases and floating-point cases.
5705 -- If we are in the right type, we can call runtime routine directly
5708 and then Rtyp /= Universal_Integer
5709 and then Rtyp /= Universal_Real
5712 Make_Function_Call (Loc,
5713 Name => New_Reference_To (RTE (Rent), Loc),
5714 Parameter_Associations => New_List (Base, Exp)));
5716 -- Otherwise we have to introduce conversions (conversions are also
5717 -- required in the universal cases, since the runtime routine is
5718 -- typed using one of the standard types).
5723 Make_Function_Call (Loc,
5724 Name => New_Reference_To (RTE (Rent), Loc),
5725 Parameter_Associations => New_List (
5726 Convert_To (Etyp, Base),
5730 Analyze_And_Resolve (N, Typ);
5734 when RE_Not_Available =>
5736 end Expand_N_Op_Expon;
5738 --------------------
5739 -- Expand_N_Op_Ge --
5740 --------------------
5742 procedure Expand_N_Op_Ge (N : Node_Id) is
5743 Typ : constant Entity_Id := Etype (N);
5744 Op1 : constant Node_Id := Left_Opnd (N);
5745 Op2 : constant Node_Id := Right_Opnd (N);
5746 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
5749 Binary_Op_Validity_Checks (N);
5751 if Is_Array_Type (Typ1) then
5752 Expand_Array_Comparison (N);
5756 if Is_Boolean_Type (Typ1) then
5757 Adjust_Condition (Op1);
5758 Adjust_Condition (Op2);
5759 Set_Etype (N, Standard_Boolean);
5760 Adjust_Result_Type (N, Typ);
5763 Rewrite_Comparison (N);
5765 -- If we still have comparison, and Vax_Float type, process it
5767 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
5768 Expand_Vax_Comparison (N);
5773 --------------------
5774 -- Expand_N_Op_Gt --
5775 --------------------
5777 procedure Expand_N_Op_Gt (N : Node_Id) is
5778 Typ : constant Entity_Id := Etype (N);
5779 Op1 : constant Node_Id := Left_Opnd (N);
5780 Op2 : constant Node_Id := Right_Opnd (N);
5781 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
5784 Binary_Op_Validity_Checks (N);
5786 if Is_Array_Type (Typ1) then
5787 Expand_Array_Comparison (N);
5791 if Is_Boolean_Type (Typ1) then
5792 Adjust_Condition (Op1);
5793 Adjust_Condition (Op2);
5794 Set_Etype (N, Standard_Boolean);
5795 Adjust_Result_Type (N, Typ);
5798 Rewrite_Comparison (N);
5800 -- If we still have comparison, and Vax_Float type, process it
5802 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
5803 Expand_Vax_Comparison (N);
5808 --------------------
5809 -- Expand_N_Op_Le --
5810 --------------------
5812 procedure Expand_N_Op_Le (N : Node_Id) is
5813 Typ : constant Entity_Id := Etype (N);
5814 Op1 : constant Node_Id := Left_Opnd (N);
5815 Op2 : constant Node_Id := Right_Opnd (N);
5816 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
5819 Binary_Op_Validity_Checks (N);
5821 if Is_Array_Type (Typ1) then
5822 Expand_Array_Comparison (N);
5826 if Is_Boolean_Type (Typ1) then
5827 Adjust_Condition (Op1);
5828 Adjust_Condition (Op2);
5829 Set_Etype (N, Standard_Boolean);
5830 Adjust_Result_Type (N, Typ);
5833 Rewrite_Comparison (N);
5835 -- If we still have comparison, and Vax_Float type, process it
5837 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
5838 Expand_Vax_Comparison (N);
5843 --------------------
5844 -- Expand_N_Op_Lt --
5845 --------------------
5847 procedure Expand_N_Op_Lt (N : Node_Id) is
5848 Typ : constant Entity_Id := Etype (N);
5849 Op1 : constant Node_Id := Left_Opnd (N);
5850 Op2 : constant Node_Id := Right_Opnd (N);
5851 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
5854 Binary_Op_Validity_Checks (N);
5856 if Is_Array_Type (Typ1) then
5857 Expand_Array_Comparison (N);
5861 if Is_Boolean_Type (Typ1) then
5862 Adjust_Condition (Op1);
5863 Adjust_Condition (Op2);
5864 Set_Etype (N, Standard_Boolean);
5865 Adjust_Result_Type (N, Typ);
5868 Rewrite_Comparison (N);
5870 -- If we still have comparison, and Vax_Float type, process it
5872 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
5873 Expand_Vax_Comparison (N);
5878 -----------------------
5879 -- Expand_N_Op_Minus --
5880 -----------------------
5882 procedure Expand_N_Op_Minus (N : Node_Id) is
5883 Loc : constant Source_Ptr := Sloc (N);
5884 Typ : constant Entity_Id := Etype (N);
5887 Unary_Op_Validity_Checks (N);
5889 if not Backend_Overflow_Checks_On_Target
5890 and then Is_Signed_Integer_Type (Etype (N))
5891 and then Do_Overflow_Check (N)
5893 -- Software overflow checking expands -expr into (0 - expr)
5896 Make_Op_Subtract (Loc,
5897 Left_Opnd => Make_Integer_Literal (Loc, 0),
5898 Right_Opnd => Right_Opnd (N)));
5900 Analyze_And_Resolve (N, Typ);
5902 -- Vax floating-point types case
5904 elsif Vax_Float (Etype (N)) then
5905 Expand_Vax_Arith (N);
5907 end Expand_N_Op_Minus;
5909 ---------------------
5910 -- Expand_N_Op_Mod --
5911 ---------------------
5913 procedure Expand_N_Op_Mod (N : Node_Id) is
5914 Loc : constant Source_Ptr := Sloc (N);
5915 Typ : constant Entity_Id := Etype (N);
5916 Left : constant Node_Id := Left_Opnd (N);
5917 Right : constant Node_Id := Right_Opnd (N);
5918 DOC : constant Boolean := Do_Overflow_Check (N);
5919 DDC : constant Boolean := Do_Division_Check (N);
5929 pragma Warnings (Off, Lhi);
5932 Binary_Op_Validity_Checks (N);
5934 Determine_Range (Right, ROK, Rlo, Rhi);
5935 Determine_Range (Left, LOK, Llo, Lhi);
5937 -- Convert mod to rem if operands are known non-negative. We do this
5938 -- since it is quite likely that this will improve the quality of code,
5939 -- (the operation now corresponds to the hardware remainder), and it
5940 -- does not seem likely that it could be harmful.
5942 if LOK and then Llo >= 0
5944 ROK and then Rlo >= 0
5947 Make_Op_Rem (Sloc (N),
5948 Left_Opnd => Left_Opnd (N),
5949 Right_Opnd => Right_Opnd (N)));
5951 -- Instead of reanalyzing the node we do the analysis manually. This
5952 -- avoids anomalies when the replacement is done in an instance and
5953 -- is epsilon more efficient.
5955 Set_Entity (N, Standard_Entity (S_Op_Rem));
5957 Set_Do_Overflow_Check (N, DOC);
5958 Set_Do_Division_Check (N, DDC);
5959 Expand_N_Op_Rem (N);
5962 -- Otherwise, normal mod processing
5965 if Is_Integer_Type (Etype (N)) then
5966 Apply_Divide_Check (N);
5969 -- Apply optimization x mod 1 = 0. We don't really need that with
5970 -- gcc, but it is useful with other back ends (e.g. AAMP), and is
5971 -- certainly harmless.
5973 if Is_Integer_Type (Etype (N))
5974 and then Compile_Time_Known_Value (Right)
5975 and then Expr_Value (Right) = Uint_1
5977 -- Call Remove_Side_Effects to ensure that any side effects in
5978 -- the ignored left operand (in particular function calls to
5979 -- user defined functions) are properly executed.
5981 Remove_Side_Effects (Left);
5983 Rewrite (N, Make_Integer_Literal (Loc, 0));
5984 Analyze_And_Resolve (N, Typ);
5988 -- Deal with annoying case of largest negative number remainder
5989 -- minus one. Gigi does not handle this case correctly, because
5990 -- it generates a divide instruction which may trap in this case.
5992 -- In fact the check is quite easy, if the right operand is -1, then
5993 -- the mod value is always 0, and we can just ignore the left operand
5994 -- completely in this case.
5996 -- The operand type may be private (e.g. in the expansion of an
5997 -- intrinsic operation) so we must use the underlying type to get the
5998 -- bounds, and convert the literals explicitly.
6002 (Type_Low_Bound (Base_Type (Underlying_Type (Etype (Left)))));
6004 if ((not ROK) or else (Rlo <= (-1) and then (-1) <= Rhi))
6006 ((not LOK) or else (Llo = LLB))
6009 Make_Conditional_Expression (Loc,
6010 Expressions => New_List (
6012 Left_Opnd => Duplicate_Subexpr (Right),
6014 Unchecked_Convert_To (Typ,
6015 Make_Integer_Literal (Loc, -1))),
6016 Unchecked_Convert_To (Typ,
6017 Make_Integer_Literal (Loc, Uint_0)),
6018 Relocate_Node (N))));
6020 Set_Analyzed (Next (Next (First (Expressions (N)))));
6021 Analyze_And_Resolve (N, Typ);
6024 end Expand_N_Op_Mod;
6026 --------------------------
6027 -- Expand_N_Op_Multiply --
6028 --------------------------
6030 procedure Expand_N_Op_Multiply (N : Node_Id) is
6031 Loc : constant Source_Ptr := Sloc (N);
6032 Lop : constant Node_Id := Left_Opnd (N);
6033 Rop : constant Node_Id := Right_Opnd (N);
6035 Lp2 : constant Boolean :=
6036 Nkind (Lop) = N_Op_Expon
6037 and then Is_Power_Of_2_For_Shift (Lop);
6039 Rp2 : constant Boolean :=
6040 Nkind (Rop) = N_Op_Expon
6041 and then Is_Power_Of_2_For_Shift (Rop);
6043 Ltyp : constant Entity_Id := Etype (Lop);
6044 Rtyp : constant Entity_Id := Etype (Rop);
6045 Typ : Entity_Id := Etype (N);
6048 Binary_Op_Validity_Checks (N);
6050 -- Special optimizations for integer types
6052 if Is_Integer_Type (Typ) then
6054 -- N * 0 = 0 for integer types
6056 if Compile_Time_Known_Value (Rop)
6057 and then Expr_Value (Rop) = Uint_0
6059 -- Call Remove_Side_Effects to ensure that any side effects in
6060 -- the ignored left operand (in particular function calls to
6061 -- user defined functions) are properly executed.
6063 Remove_Side_Effects (Lop);
6065 Rewrite (N, Make_Integer_Literal (Loc, Uint_0));
6066 Analyze_And_Resolve (N, Typ);
6070 -- Similar handling for 0 * N = 0
6072 if Compile_Time_Known_Value (Lop)
6073 and then Expr_Value (Lop) = Uint_0
6075 Remove_Side_Effects (Rop);
6076 Rewrite (N, Make_Integer_Literal (Loc, Uint_0));
6077 Analyze_And_Resolve (N, Typ);
6081 -- N * 1 = 1 * N = N for integer types
6083 -- This optimisation is not done if we are going to
6084 -- rewrite the product 1 * 2 ** N to a shift.
6086 if Compile_Time_Known_Value (Rop)
6087 and then Expr_Value (Rop) = Uint_1
6093 elsif Compile_Time_Known_Value (Lop)
6094 and then Expr_Value (Lop) = Uint_1
6102 -- Convert x * 2 ** y to Shift_Left (x, y). Note that the fact that
6103 -- Is_Power_Of_2_For_Shift is set means that we know that our left
6104 -- operand is an integer, as required for this to work.
6109 -- Convert 2 ** A * 2 ** B into 2 ** (A + B)
6113 Left_Opnd => Make_Integer_Literal (Loc, 2),
6116 Left_Opnd => Right_Opnd (Lop),
6117 Right_Opnd => Right_Opnd (Rop))));
6118 Analyze_And_Resolve (N, Typ);
6123 Make_Op_Shift_Left (Loc,
6126 Convert_To (Standard_Natural, Right_Opnd (Rop))));
6127 Analyze_And_Resolve (N, Typ);
6131 -- Same processing for the operands the other way round
6135 Make_Op_Shift_Left (Loc,
6138 Convert_To (Standard_Natural, Right_Opnd (Lop))));
6139 Analyze_And_Resolve (N, Typ);
6143 -- Do required fixup of universal fixed operation
6145 if Typ = Universal_Fixed then
6146 Fixup_Universal_Fixed_Operation (N);
6150 -- Multiplications with fixed-point results
6152 if Is_Fixed_Point_Type (Typ) then
6154 -- No special processing if Treat_Fixed_As_Integer is set, since from
6155 -- a semantic point of view such operations are simply integer
6156 -- operations and will be treated that way.
6158 if not Treat_Fixed_As_Integer (N) then
6160 -- Case of fixed * integer => fixed
6162 if Is_Integer_Type (Rtyp) then
6163 Expand_Multiply_Fixed_By_Integer_Giving_Fixed (N);
6165 -- Case of integer * fixed => fixed
6167 elsif Is_Integer_Type (Ltyp) then
6168 Expand_Multiply_Integer_By_Fixed_Giving_Fixed (N);
6170 -- Case of fixed * fixed => fixed
6173 Expand_Multiply_Fixed_By_Fixed_Giving_Fixed (N);
6177 -- Other cases of multiplication of fixed-point operands. Again we
6178 -- exclude the cases where Treat_Fixed_As_Integer flag is set.
6180 elsif (Is_Fixed_Point_Type (Ltyp) or else Is_Fixed_Point_Type (Rtyp))
6181 and then not Treat_Fixed_As_Integer (N)
6183 if Is_Integer_Type (Typ) then
6184 Expand_Multiply_Fixed_By_Fixed_Giving_Integer (N);
6186 pragma Assert (Is_Floating_Point_Type (Typ));
6187 Expand_Multiply_Fixed_By_Fixed_Giving_Float (N);
6190 -- Mixed-mode operations can appear in a non-static universal context,
6191 -- in which case the integer argument must be converted explicitly.
6193 elsif Typ = Universal_Real
6194 and then Is_Integer_Type (Rtyp)
6196 Rewrite (Rop, Convert_To (Universal_Real, Relocate_Node (Rop)));
6198 Analyze_And_Resolve (Rop, Universal_Real);
6200 elsif Typ = Universal_Real
6201 and then Is_Integer_Type (Ltyp)
6203 Rewrite (Lop, Convert_To (Universal_Real, Relocate_Node (Lop)));
6205 Analyze_And_Resolve (Lop, Universal_Real);
6207 -- Non-fixed point cases, check software overflow checking required
6209 elsif Is_Signed_Integer_Type (Etype (N)) then
6210 Apply_Arithmetic_Overflow_Check (N);
6212 -- Deal with VAX float case
6214 elsif Vax_Float (Typ) then
6215 Expand_Vax_Arith (N);
6218 end Expand_N_Op_Multiply;
6220 --------------------
6221 -- Expand_N_Op_Ne --
6222 --------------------
6224 procedure Expand_N_Op_Ne (N : Node_Id) is
6225 Typ : constant Entity_Id := Etype (Left_Opnd (N));
6228 -- Case of elementary type with standard operator
6230 if Is_Elementary_Type (Typ)
6231 and then Sloc (Entity (N)) = Standard_Location
6233 Binary_Op_Validity_Checks (N);
6235 -- Boolean types (requiring handling of non-standard case)
6237 if Is_Boolean_Type (Typ) then
6238 Adjust_Condition (Left_Opnd (N));
6239 Adjust_Condition (Right_Opnd (N));
6240 Set_Etype (N, Standard_Boolean);
6241 Adjust_Result_Type (N, Typ);
6244 Rewrite_Comparison (N);
6246 -- If we still have comparison for Vax_Float, process it
6248 if Vax_Float (Typ) and then Nkind (N) in N_Op_Compare then
6249 Expand_Vax_Comparison (N);
6253 -- For all cases other than elementary types, we rewrite node as the
6254 -- negation of an equality operation, and reanalyze. The equality to be
6255 -- used is defined in the same scope and has the same signature. This
6256 -- signature must be set explicitly since in an instance it may not have
6257 -- the same visibility as in the generic unit. This avoids duplicating
6258 -- or factoring the complex code for record/array equality tests etc.
6262 Loc : constant Source_Ptr := Sloc (N);
6264 Ne : constant Entity_Id := Entity (N);
6267 Binary_Op_Validity_Checks (N);
6273 Left_Opnd => Left_Opnd (N),
6274 Right_Opnd => Right_Opnd (N)));
6275 Set_Paren_Count (Right_Opnd (Neg), 1);
6277 if Scope (Ne) /= Standard_Standard then
6278 Set_Entity (Right_Opnd (Neg), Corresponding_Equality (Ne));
6281 -- For navigation purposes, the inequality is treated as an
6282 -- implicit reference to the corresponding equality. Preserve the
6283 -- Comes_From_ source flag so that the proper Xref entry is
6286 Preserve_Comes_From_Source (Neg, N);
6287 Preserve_Comes_From_Source (Right_Opnd (Neg), N);
6289 Analyze_And_Resolve (N, Standard_Boolean);
6294 ---------------------
6295 -- Expand_N_Op_Not --
6296 ---------------------
6298 -- If the argument is other than a Boolean array type, there is no special
6299 -- expansion required.
6301 -- For the packed case, we call the special routine in Exp_Pakd, except
6302 -- that if the component size is greater than one, we use the standard
6303 -- routine generating a gruesome loop (it is so peculiar to have packed
6304 -- arrays with non-standard Boolean representations anyway, so it does not
6305 -- matter that we do not handle this case efficiently).
6307 -- For the unpacked case (and for the special packed case where we have non
6308 -- standard Booleans, as discussed above), we generate and insert into the
6309 -- tree the following function definition:
6311 -- function Nnnn (A : arr) is
6314 -- for J in a'range loop
6315 -- B (J) := not A (J);
6320 -- Here arr is the actual subtype of the parameter (and hence always
6321 -- constrained). Then we replace the not with a call to this function.
6323 procedure Expand_N_Op_Not (N : Node_Id) is
6324 Loc : constant Source_Ptr := Sloc (N);
6325 Typ : constant Entity_Id := Etype (N);
6334 Func_Name : Entity_Id;
6335 Loop_Statement : Node_Id;
6338 Unary_Op_Validity_Checks (N);
6340 -- For boolean operand, deal with non-standard booleans
6342 if Is_Boolean_Type (Typ) then
6343 Adjust_Condition (Right_Opnd (N));
6344 Set_Etype (N, Standard_Boolean);
6345 Adjust_Result_Type (N, Typ);
6349 -- Only array types need any other processing
6351 if not Is_Array_Type (Typ) then
6355 -- Case of array operand. If bit packed with a component size of 1,
6356 -- handle it in Exp_Pakd if the operand is known to be aligned.
6358 if Is_Bit_Packed_Array (Typ)
6359 and then Component_Size (Typ) = 1
6360 and then not Is_Possibly_Unaligned_Object (Right_Opnd (N))
6362 Expand_Packed_Not (N);
6366 -- Case of array operand which is not bit-packed. If the context is
6367 -- a safe assignment, call in-place operation, If context is a larger
6368 -- boolean expression in the context of a safe assignment, expansion is
6369 -- done by enclosing operation.
6371 Opnd := Relocate_Node (Right_Opnd (N));
6372 Convert_To_Actual_Subtype (Opnd);
6373 Arr := Etype (Opnd);
6374 Ensure_Defined (Arr, N);
6375 Silly_Boolean_Array_Not_Test (N, Arr);
6377 if Nkind (Parent (N)) = N_Assignment_Statement then
6378 if Safe_In_Place_Array_Op (Name (Parent (N)), N, Empty) then
6379 Build_Boolean_Array_Proc_Call (Parent (N), Opnd, Empty);
6382 -- Special case the negation of a binary operation
6384 elsif Nkind_In (Opnd, N_Op_And, N_Op_Or, N_Op_Xor)
6385 and then Safe_In_Place_Array_Op
6386 (Name (Parent (N)), Left_Opnd (Opnd), Right_Opnd (Opnd))
6388 Build_Boolean_Array_Proc_Call (Parent (N), Opnd, Empty);
6392 elsif Nkind (Parent (N)) in N_Binary_Op
6393 and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
6396 Op1 : constant Node_Id := Left_Opnd (Parent (N));
6397 Op2 : constant Node_Id := Right_Opnd (Parent (N));
6398 Lhs : constant Node_Id := Name (Parent (Parent (N)));
6401 if Safe_In_Place_Array_Op (Lhs, Op1, Op2) then
6403 and then Nkind (Op2) = N_Op_Not
6405 -- (not A) op (not B) can be reduced to a single call
6410 and then Nkind (Parent (N)) = N_Op_Xor
6412 -- A xor (not B) can also be special-cased
6420 A := Make_Defining_Identifier (Loc, Name_uA);
6421 B := Make_Defining_Identifier (Loc, Name_uB);
6422 J := Make_Defining_Identifier (Loc, Name_uJ);
6425 Make_Indexed_Component (Loc,
6426 Prefix => New_Reference_To (A, Loc),
6427 Expressions => New_List (New_Reference_To (J, Loc)));
6430 Make_Indexed_Component (Loc,
6431 Prefix => New_Reference_To (B, Loc),
6432 Expressions => New_List (New_Reference_To (J, Loc)));
6435 Make_Implicit_Loop_Statement (N,
6436 Identifier => Empty,
6439 Make_Iteration_Scheme (Loc,
6440 Loop_Parameter_Specification =>
6441 Make_Loop_Parameter_Specification (Loc,
6442 Defining_Identifier => J,
6443 Discrete_Subtype_Definition =>
6444 Make_Attribute_Reference (Loc,
6445 Prefix => Make_Identifier (Loc, Chars (A)),
6446 Attribute_Name => Name_Range))),
6448 Statements => New_List (
6449 Make_Assignment_Statement (Loc,
6451 Expression => Make_Op_Not (Loc, A_J))));
6453 Func_Name := Make_Defining_Identifier (Loc, New_Internal_Name ('N'));
6454 Set_Is_Inlined (Func_Name);
6457 Make_Subprogram_Body (Loc,
6459 Make_Function_Specification (Loc,
6460 Defining_Unit_Name => Func_Name,
6461 Parameter_Specifications => New_List (
6462 Make_Parameter_Specification (Loc,
6463 Defining_Identifier => A,
6464 Parameter_Type => New_Reference_To (Typ, Loc))),
6465 Result_Definition => New_Reference_To (Typ, Loc)),
6467 Declarations => New_List (
6468 Make_Object_Declaration (Loc,
6469 Defining_Identifier => B,
6470 Object_Definition => New_Reference_To (Arr, Loc))),
6472 Handled_Statement_Sequence =>
6473 Make_Handled_Sequence_Of_Statements (Loc,
6474 Statements => New_List (
6476 Make_Simple_Return_Statement (Loc,
6478 Make_Identifier (Loc, Chars (B)))))));
6481 Make_Function_Call (Loc,
6482 Name => New_Reference_To (Func_Name, Loc),
6483 Parameter_Associations => New_List (Opnd)));
6485 Analyze_And_Resolve (N, Typ);
6486 end Expand_N_Op_Not;
6488 --------------------
6489 -- Expand_N_Op_Or --
6490 --------------------
6492 procedure Expand_N_Op_Or (N : Node_Id) is
6493 Typ : constant Entity_Id := Etype (N);
6496 Binary_Op_Validity_Checks (N);
6498 if Is_Array_Type (Etype (N)) then
6499 Expand_Boolean_Operator (N);
6501 elsif Is_Boolean_Type (Etype (N)) then
6502 Adjust_Condition (Left_Opnd (N));
6503 Adjust_Condition (Right_Opnd (N));
6504 Set_Etype (N, Standard_Boolean);
6505 Adjust_Result_Type (N, Typ);
6509 ----------------------
6510 -- Expand_N_Op_Plus --
6511 ----------------------
6513 procedure Expand_N_Op_Plus (N : Node_Id) is
6515 Unary_Op_Validity_Checks (N);
6516 end Expand_N_Op_Plus;
6518 ---------------------
6519 -- Expand_N_Op_Rem --
6520 ---------------------
6522 procedure Expand_N_Op_Rem (N : Node_Id) is
6523 Loc : constant Source_Ptr := Sloc (N);
6524 Typ : constant Entity_Id := Etype (N);
6526 Left : constant Node_Id := Left_Opnd (N);
6527 Right : constant Node_Id := Right_Opnd (N);
6537 pragma Warnings (Off, Lhi);
6540 Binary_Op_Validity_Checks (N);
6542 if Is_Integer_Type (Etype (N)) then
6543 Apply_Divide_Check (N);
6546 -- Apply optimization x rem 1 = 0. We don't really need that with gcc,
6547 -- but it is useful with other back ends (e.g. AAMP), and is certainly
6550 if Is_Integer_Type (Etype (N))
6551 and then Compile_Time_Known_Value (Right)
6552 and then Expr_Value (Right) = Uint_1
6554 -- Call Remove_Side_Effects to ensure that any side effects in the
6555 -- ignored left operand (in particular function calls to user defined
6556 -- functions) are properly executed.
6558 Remove_Side_Effects (Left);
6560 Rewrite (N, Make_Integer_Literal (Loc, 0));
6561 Analyze_And_Resolve (N, Typ);
6565 -- Deal with annoying case of largest negative number remainder minus
6566 -- one. Gigi does not handle this case correctly, because it generates
6567 -- a divide instruction which may trap in this case.
6569 -- In fact the check is quite easy, if the right operand is -1, then
6570 -- the remainder is always 0, and we can just ignore the left operand
6571 -- completely in this case.
6573 Determine_Range (Right, ROK, Rlo, Rhi);
6574 Determine_Range (Left, LOK, Llo, Lhi);
6576 -- The operand type may be private (e.g. in the expansion of an
6577 -- intrinsic operation) so we must use the underlying type to get the
6578 -- bounds, and convert the literals explicitly.
6582 (Type_Low_Bound (Base_Type (Underlying_Type (Etype (Left)))));
6584 -- Now perform the test, generating code only if needed
6586 if ((not ROK) or else (Rlo <= (-1) and then (-1) <= Rhi))
6588 ((not LOK) or else (Llo = LLB))
6591 Make_Conditional_Expression (Loc,
6592 Expressions => New_List (
6594 Left_Opnd => Duplicate_Subexpr (Right),
6596 Unchecked_Convert_To (Typ,
6597 Make_Integer_Literal (Loc, -1))),
6599 Unchecked_Convert_To (Typ,
6600 Make_Integer_Literal (Loc, Uint_0)),
6602 Relocate_Node (N))));
6604 Set_Analyzed (Next (Next (First (Expressions (N)))));
6605 Analyze_And_Resolve (N, Typ);
6607 end Expand_N_Op_Rem;
6609 -----------------------------
6610 -- Expand_N_Op_Rotate_Left --
6611 -----------------------------
6613 procedure Expand_N_Op_Rotate_Left (N : Node_Id) is
6615 Binary_Op_Validity_Checks (N);
6616 end Expand_N_Op_Rotate_Left;
6618 ------------------------------
6619 -- Expand_N_Op_Rotate_Right --
6620 ------------------------------
6622 procedure Expand_N_Op_Rotate_Right (N : Node_Id) is
6624 Binary_Op_Validity_Checks (N);
6625 end Expand_N_Op_Rotate_Right;
6627 ----------------------------
6628 -- Expand_N_Op_Shift_Left --
6629 ----------------------------
6631 procedure Expand_N_Op_Shift_Left (N : Node_Id) is
6633 Binary_Op_Validity_Checks (N);
6634 end Expand_N_Op_Shift_Left;
6636 -----------------------------
6637 -- Expand_N_Op_Shift_Right --
6638 -----------------------------
6640 procedure Expand_N_Op_Shift_Right (N : Node_Id) is
6642 Binary_Op_Validity_Checks (N);
6643 end Expand_N_Op_Shift_Right;
6645 ----------------------------------------
6646 -- Expand_N_Op_Shift_Right_Arithmetic --
6647 ----------------------------------------
6649 procedure Expand_N_Op_Shift_Right_Arithmetic (N : Node_Id) is
6651 Binary_Op_Validity_Checks (N);
6652 end Expand_N_Op_Shift_Right_Arithmetic;
6654 --------------------------
6655 -- Expand_N_Op_Subtract --
6656 --------------------------
6658 procedure Expand_N_Op_Subtract (N : Node_Id) is
6659 Typ : constant Entity_Id := Etype (N);
6662 Binary_Op_Validity_Checks (N);
6664 -- N - 0 = N for integer types
6666 if Is_Integer_Type (Typ)
6667 and then Compile_Time_Known_Value (Right_Opnd (N))
6668 and then Expr_Value (Right_Opnd (N)) = 0
6670 Rewrite (N, Left_Opnd (N));
6674 -- Arithmetic overflow checks for signed integer/fixed point types
6676 if Is_Signed_Integer_Type (Typ)
6677 or else Is_Fixed_Point_Type (Typ)
6679 Apply_Arithmetic_Overflow_Check (N);
6681 -- Vax floating-point types case
6683 elsif Vax_Float (Typ) then
6684 Expand_Vax_Arith (N);
6686 end Expand_N_Op_Subtract;
6688 ---------------------
6689 -- Expand_N_Op_Xor --
6690 ---------------------
6692 procedure Expand_N_Op_Xor (N : Node_Id) is
6693 Typ : constant Entity_Id := Etype (N);
6696 Binary_Op_Validity_Checks (N);
6698 if Is_Array_Type (Etype (N)) then
6699 Expand_Boolean_Operator (N);
6701 elsif Is_Boolean_Type (Etype (N)) then
6702 Adjust_Condition (Left_Opnd (N));
6703 Adjust_Condition (Right_Opnd (N));
6704 Set_Etype (N, Standard_Boolean);
6705 Adjust_Result_Type (N, Typ);
6707 end Expand_N_Op_Xor;
6709 ----------------------
6710 -- Expand_N_Or_Else --
6711 ----------------------
6713 -- Expand into conditional expression if Actions present, and also
6714 -- deal with optimizing case of arguments being True or False.
6716 procedure Expand_N_Or_Else (N : Node_Id) is
6717 Loc : constant Source_Ptr := Sloc (N);
6718 Typ : constant Entity_Id := Etype (N);
6719 Left : constant Node_Id := Left_Opnd (N);
6720 Right : constant Node_Id := Right_Opnd (N);
6724 -- Deal with non-standard booleans
6726 if Is_Boolean_Type (Typ) then
6727 Adjust_Condition (Left);
6728 Adjust_Condition (Right);
6729 Set_Etype (N, Standard_Boolean);
6732 -- Check for cases where left argument is known to be True or False
6734 if Compile_Time_Known_Value (Left) then
6736 -- If left argument is False, change (False or else Right) to Right.
6737 -- Any actions associated with Right will be executed unconditionally
6738 -- and can thus be inserted into the tree unconditionally.
6740 if Expr_Value_E (Left) = Standard_False then
6741 if Present (Actions (N)) then
6742 Insert_Actions (N, Actions (N));
6747 -- If left argument is True, change (True and then Right) to True. In
6748 -- this case we can forget the actions associated with Right, since
6749 -- they will never be executed.
6751 else pragma Assert (Expr_Value_E (Left) = Standard_True);
6752 Kill_Dead_Code (Right);
6753 Kill_Dead_Code (Actions (N));
6754 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
6757 Adjust_Result_Type (N, Typ);
6761 -- If Actions are present, we expand
6763 -- left or else right
6767 -- if left then True else right end
6769 -- with the actions becoming the Else_Actions of the conditional
6770 -- expression. This conditional expression is then further expanded
6771 -- (and will eventually disappear)
6773 if Present (Actions (N)) then
6774 Actlist := Actions (N);
6776 Make_Conditional_Expression (Loc,
6777 Expressions => New_List (
6779 New_Occurrence_Of (Standard_True, Loc),
6782 Set_Else_Actions (N, Actlist);
6783 Analyze_And_Resolve (N, Standard_Boolean);
6784 Adjust_Result_Type (N, Typ);
6788 -- No actions present, check for cases of right argument True/False
6790 if Compile_Time_Known_Value (Right) then
6792 -- Change (Left or else False) to Left. Note that we know there are
6793 -- no actions associated with the True operand, since we just checked
6794 -- for this case above.
6796 if Expr_Value_E (Right) = Standard_False then
6799 -- Change (Left or else True) to True, making sure to preserve any
6800 -- side effects associated with the Left operand.
6802 else pragma Assert (Expr_Value_E (Right) = Standard_True);
6803 Remove_Side_Effects (Left);
6805 (N, New_Occurrence_Of (Standard_True, Loc));
6809 Adjust_Result_Type (N, Typ);
6810 end Expand_N_Or_Else;
6812 -----------------------------------
6813 -- Expand_N_Qualified_Expression --
6814 -----------------------------------
6816 procedure Expand_N_Qualified_Expression (N : Node_Id) is
6817 Operand : constant Node_Id := Expression (N);
6818 Target_Type : constant Entity_Id := Entity (Subtype_Mark (N));
6821 -- Do validity check if validity checking operands
6823 if Validity_Checks_On
6824 and then Validity_Check_Operands
6826 Ensure_Valid (Operand);
6829 -- Apply possible constraint check
6831 Apply_Constraint_Check (Operand, Target_Type, No_Sliding => True);
6832 end Expand_N_Qualified_Expression;
6834 ---------------------------------
6835 -- Expand_N_Selected_Component --
6836 ---------------------------------
6838 -- If the selector is a discriminant of a concurrent object, rewrite the
6839 -- prefix to denote the corresponding record type.
6841 procedure Expand_N_Selected_Component (N : Node_Id) is
6842 Loc : constant Source_Ptr := Sloc (N);
6843 Par : constant Node_Id := Parent (N);
6844 P : constant Node_Id := Prefix (N);
6845 Ptyp : Entity_Id := Underlying_Type (Etype (P));
6850 function In_Left_Hand_Side (Comp : Node_Id) return Boolean;
6851 -- Gigi needs a temporary for prefixes that depend on a discriminant,
6852 -- unless the context of an assignment can provide size information.
6853 -- Don't we have a general routine that does this???
6855 -----------------------
6856 -- In_Left_Hand_Side --
6857 -----------------------
6859 function In_Left_Hand_Side (Comp : Node_Id) return Boolean is
6861 return (Nkind (Parent (Comp)) = N_Assignment_Statement
6862 and then Comp = Name (Parent (Comp)))
6863 or else (Present (Parent (Comp))
6864 and then Nkind (Parent (Comp)) in N_Subexpr
6865 and then In_Left_Hand_Side (Parent (Comp)));
6866 end In_Left_Hand_Side;
6868 -- Start of processing for Expand_N_Selected_Component
6871 -- Insert explicit dereference if required
6873 if Is_Access_Type (Ptyp) then
6874 Insert_Explicit_Dereference (P);
6875 Analyze_And_Resolve (P, Designated_Type (Ptyp));
6877 if Ekind (Etype (P)) = E_Private_Subtype
6878 and then Is_For_Access_Subtype (Etype (P))
6880 Set_Etype (P, Base_Type (Etype (P)));
6886 -- Deal with discriminant check required
6888 if Do_Discriminant_Check (N) then
6890 -- Present the discriminant checking function to the backend, so that
6891 -- it can inline the call to the function.
6894 (Discriminant_Checking_Func
6895 (Original_Record_Component (Entity (Selector_Name (N)))));
6897 -- Now reset the flag and generate the call
6899 Set_Do_Discriminant_Check (N, False);
6900 Generate_Discriminant_Check (N);
6903 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
6904 -- function, then additional actuals must be passed.
6906 if Ada_Version >= Ada_05
6907 and then Is_Build_In_Place_Function_Call (P)
6909 Make_Build_In_Place_Call_In_Anonymous_Context (P);
6912 -- Gigi cannot handle unchecked conversions that are the prefix of a
6913 -- selected component with discriminants. This must be checked during
6914 -- expansion, because during analysis the type of the selector is not
6915 -- known at the point the prefix is analyzed. If the conversion is the
6916 -- target of an assignment, then we cannot force the evaluation.
6918 if Nkind (Prefix (N)) = N_Unchecked_Type_Conversion
6919 and then Has_Discriminants (Etype (N))
6920 and then not In_Left_Hand_Side (N)
6922 Force_Evaluation (Prefix (N));
6925 -- Remaining processing applies only if selector is a discriminant
6927 if Ekind (Entity (Selector_Name (N))) = E_Discriminant then
6929 -- If the selector is a discriminant of a constrained record type,
6930 -- we may be able to rewrite the expression with the actual value
6931 -- of the discriminant, a useful optimization in some cases.
6933 if Is_Record_Type (Ptyp)
6934 and then Has_Discriminants (Ptyp)
6935 and then Is_Constrained (Ptyp)
6937 -- Do this optimization for discrete types only, and not for
6938 -- access types (access discriminants get us into trouble!)
6940 if not Is_Discrete_Type (Etype (N)) then
6943 -- Don't do this on the left hand of an assignment statement.
6944 -- Normally one would think that references like this would
6945 -- not occur, but they do in generated code, and mean that
6946 -- we really do want to assign the discriminant!
6948 elsif Nkind (Par) = N_Assignment_Statement
6949 and then Name (Par) = N
6953 -- Don't do this optimization for the prefix of an attribute or
6954 -- the operand of an object renaming declaration since these are
6955 -- contexts where we do not want the value anyway.
6957 elsif (Nkind (Par) = N_Attribute_Reference
6958 and then Prefix (Par) = N)
6959 or else Is_Renamed_Object (N)
6963 -- Don't do this optimization if we are within the code for a
6964 -- discriminant check, since the whole point of such a check may
6965 -- be to verify the condition on which the code below depends!
6967 elsif Is_In_Discriminant_Check (N) then
6970 -- Green light to see if we can do the optimization. There is
6971 -- still one condition that inhibits the optimization below but
6972 -- now is the time to check the particular discriminant.
6975 -- Loop through discriminants to find the matching discriminant
6976 -- constraint to see if we can copy it.
6978 Disc := First_Discriminant (Ptyp);
6979 Dcon := First_Elmt (Discriminant_Constraint (Ptyp));
6980 Discr_Loop : while Present (Dcon) loop
6982 -- Check if this is the matching discriminant
6984 if Disc = Entity (Selector_Name (N)) then
6986 -- Here we have the matching discriminant. Check for
6987 -- the case of a discriminant of a component that is
6988 -- constrained by an outer discriminant, which cannot
6989 -- be optimized away.
6992 Denotes_Discriminant
6993 (Node (Dcon), Check_Concurrent => True)
6997 -- In the context of a case statement, the expression may
6998 -- have the base type of the discriminant, and we need to
6999 -- preserve the constraint to avoid spurious errors on
7002 elsif Nkind (Parent (N)) = N_Case_Statement
7003 and then Etype (Node (Dcon)) /= Etype (Disc)
7006 Make_Qualified_Expression (Loc,
7008 New_Occurrence_Of (Etype (Disc), Loc),
7010 New_Copy_Tree (Node (Dcon))));
7011 Analyze_And_Resolve (N, Etype (Disc));
7013 -- In case that comes out as a static expression,
7014 -- reset it (a selected component is never static).
7016 Set_Is_Static_Expression (N, False);
7019 -- Otherwise we can just copy the constraint, but the
7020 -- result is certainly not static! In some cases the
7021 -- discriminant constraint has been analyzed in the
7022 -- context of the original subtype indication, but for
7023 -- itypes the constraint might not have been analyzed
7024 -- yet, and this must be done now.
7027 Rewrite (N, New_Copy_Tree (Node (Dcon)));
7028 Analyze_And_Resolve (N);
7029 Set_Is_Static_Expression (N, False);
7035 Next_Discriminant (Disc);
7036 end loop Discr_Loop;
7038 -- Note: the above loop should always find a matching
7039 -- discriminant, but if it does not, we just missed an
7040 -- optimization due to some glitch (perhaps a previous error),
7046 -- The only remaining processing is in the case of a discriminant of
7047 -- a concurrent object, where we rewrite the prefix to denote the
7048 -- corresponding record type. If the type is derived and has renamed
7049 -- discriminants, use corresponding discriminant, which is the one
7050 -- that appears in the corresponding record.
7052 if not Is_Concurrent_Type (Ptyp) then
7056 Disc := Entity (Selector_Name (N));
7058 if Is_Derived_Type (Ptyp)
7059 and then Present (Corresponding_Discriminant (Disc))
7061 Disc := Corresponding_Discriminant (Disc);
7065 Make_Selected_Component (Loc,
7067 Unchecked_Convert_To (Corresponding_Record_Type (Ptyp),
7069 Selector_Name => Make_Identifier (Loc, Chars (Disc)));
7074 end Expand_N_Selected_Component;
7076 --------------------
7077 -- Expand_N_Slice --
7078 --------------------
7080 procedure Expand_N_Slice (N : Node_Id) is
7081 Loc : constant Source_Ptr := Sloc (N);
7082 Typ : constant Entity_Id := Etype (N);
7083 Pfx : constant Node_Id := Prefix (N);
7084 Ptp : Entity_Id := Etype (Pfx);
7086 function Is_Procedure_Actual (N : Node_Id) return Boolean;
7087 -- Check whether the argument is an actual for a procedure call, in
7088 -- which case the expansion of a bit-packed slice is deferred until the
7089 -- call itself is expanded. The reason this is required is that we might
7090 -- have an IN OUT or OUT parameter, and the copy out is essential, and
7091 -- that copy out would be missed if we created a temporary here in
7092 -- Expand_N_Slice. Note that we don't bother to test specifically for an
7093 -- IN OUT or OUT mode parameter, since it is a bit tricky to do, and it
7094 -- is harmless to defer expansion in the IN case, since the call
7095 -- processing will still generate the appropriate copy in operation,
7096 -- which will take care of the slice.
7098 procedure Make_Temporary;
7099 -- Create a named variable for the value of the slice, in cases where
7100 -- the back-end cannot handle it properly, e.g. when packed types or
7101 -- unaligned slices are involved.
7103 -------------------------
7104 -- Is_Procedure_Actual --
7105 -------------------------
7107 function Is_Procedure_Actual (N : Node_Id) return Boolean is
7108 Par : Node_Id := Parent (N);
7112 -- If our parent is a procedure call we can return
7114 if Nkind (Par) = N_Procedure_Call_Statement then
7117 -- If our parent is a type conversion, keep climbing the tree,
7118 -- since a type conversion can be a procedure actual. Also keep
7119 -- climbing if parameter association or a qualified expression,
7120 -- since these are additional cases that do can appear on
7121 -- procedure actuals.
7123 elsif Nkind_In (Par, N_Type_Conversion,
7124 N_Parameter_Association,
7125 N_Qualified_Expression)
7127 Par := Parent (Par);
7129 -- Any other case is not what we are looking for
7135 end Is_Procedure_Actual;
7137 --------------------
7138 -- Make_Temporary --
7139 --------------------
7141 procedure Make_Temporary is
7143 Ent : constant Entity_Id :=
7144 Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
7147 Make_Object_Declaration (Loc,
7148 Defining_Identifier => Ent,
7149 Object_Definition => New_Occurrence_Of (Typ, Loc));
7151 Set_No_Initialization (Decl);
7153 Insert_Actions (N, New_List (
7155 Make_Assignment_Statement (Loc,
7156 Name => New_Occurrence_Of (Ent, Loc),
7157 Expression => Relocate_Node (N))));
7159 Rewrite (N, New_Occurrence_Of (Ent, Loc));
7160 Analyze_And_Resolve (N, Typ);
7163 -- Start of processing for Expand_N_Slice
7166 -- Special handling for access types
7168 if Is_Access_Type (Ptp) then
7170 Ptp := Designated_Type (Ptp);
7173 Make_Explicit_Dereference (Sloc (N),
7174 Prefix => Relocate_Node (Pfx)));
7176 Analyze_And_Resolve (Pfx, Ptp);
7179 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
7180 -- function, then additional actuals must be passed.
7182 if Ada_Version >= Ada_05
7183 and then Is_Build_In_Place_Function_Call (Pfx)
7185 Make_Build_In_Place_Call_In_Anonymous_Context (Pfx);
7188 -- Range checks are potentially also needed for cases involving a slice
7189 -- indexed by a subtype indication, but Do_Range_Check can currently
7190 -- only be set for expressions ???
7192 if not Index_Checks_Suppressed (Ptp)
7193 and then (not Is_Entity_Name (Pfx)
7194 or else not Index_Checks_Suppressed (Entity (Pfx)))
7195 and then Nkind (Discrete_Range (N)) /= N_Subtype_Indication
7197 -- Do not enable range check to nodes associated with the frontend
7198 -- expansion of the dispatch table. We first check if Ada.Tags is
7199 -- already loaded to avoid the addition of an undesired dependence
7200 -- on such run-time unit.
7205 (RTU_Loaded (Ada_Tags)
7206 and then Nkind (Prefix (N)) = N_Selected_Component
7207 and then Present (Entity (Selector_Name (Prefix (N))))
7208 and then Entity (Selector_Name (Prefix (N))) =
7209 RTE_Record_Component (RE_Prims_Ptr)))
7211 Enable_Range_Check (Discrete_Range (N));
7214 -- The remaining case to be handled is packed slices. We can leave
7215 -- packed slices as they are in the following situations:
7217 -- 1. Right or left side of an assignment (we can handle this
7218 -- situation correctly in the assignment statement expansion).
7220 -- 2. Prefix of indexed component (the slide is optimized away in this
7221 -- case, see the start of Expand_N_Slice.)
7223 -- 3. Object renaming declaration, since we want the name of the
7224 -- slice, not the value.
7226 -- 4. Argument to procedure call, since copy-in/copy-out handling may
7227 -- be required, and this is handled in the expansion of call
7230 -- 5. Prefix of an address attribute (this is an error which is caught
7231 -- elsewhere, and the expansion would interfere with generating the
7234 if not Is_Packed (Typ) then
7236 -- Apply transformation for actuals of a function call, where
7237 -- Expand_Actuals is not used.
7239 if Nkind (Parent (N)) = N_Function_Call
7240 and then Is_Possibly_Unaligned_Slice (N)
7245 elsif Nkind (Parent (N)) = N_Assignment_Statement
7246 or else (Nkind (Parent (Parent (N))) = N_Assignment_Statement
7247 and then Parent (N) = Name (Parent (Parent (N))))
7251 elsif Nkind (Parent (N)) = N_Indexed_Component
7252 or else Is_Renamed_Object (N)
7253 or else Is_Procedure_Actual (N)
7257 elsif Nkind (Parent (N)) = N_Attribute_Reference
7258 and then Attribute_Name (Parent (N)) = Name_Address
7267 ------------------------------
7268 -- Expand_N_Type_Conversion --
7269 ------------------------------
7271 procedure Expand_N_Type_Conversion (N : Node_Id) is
7272 Loc : constant Source_Ptr := Sloc (N);
7273 Operand : constant Node_Id := Expression (N);
7274 Target_Type : constant Entity_Id := Etype (N);
7275 Operand_Type : Entity_Id := Etype (Operand);
7277 procedure Handle_Changed_Representation;
7278 -- This is called in the case of record and array type conversions to
7279 -- see if there is a change of representation to be handled. Change of
7280 -- representation is actually handled at the assignment statement level,
7281 -- and what this procedure does is rewrite node N conversion as an
7282 -- assignment to temporary. If there is no change of representation,
7283 -- then the conversion node is unchanged.
7285 procedure Real_Range_Check;
7286 -- Handles generation of range check for real target value
7288 -----------------------------------
7289 -- Handle_Changed_Representation --
7290 -----------------------------------
7292 procedure Handle_Changed_Representation is
7301 -- Nothing else to do if no change of representation
7303 if Same_Representation (Operand_Type, Target_Type) then
7306 -- The real change of representation work is done by the assignment
7307 -- statement processing. So if this type conversion is appearing as
7308 -- the expression of an assignment statement, nothing needs to be
7309 -- done to the conversion.
7311 elsif Nkind (Parent (N)) = N_Assignment_Statement then
7314 -- Otherwise we need to generate a temporary variable, and do the
7315 -- change of representation assignment into that temporary variable.
7316 -- The conversion is then replaced by a reference to this variable.
7321 -- If type is unconstrained we have to add a constraint, copied
7322 -- from the actual value of the left hand side.
7324 if not Is_Constrained (Target_Type) then
7325 if Has_Discriminants (Operand_Type) then
7326 Disc := First_Discriminant (Operand_Type);
7328 if Disc /= First_Stored_Discriminant (Operand_Type) then
7329 Disc := First_Stored_Discriminant (Operand_Type);
7333 while Present (Disc) loop
7335 Make_Selected_Component (Loc,
7336 Prefix => Duplicate_Subexpr_Move_Checks (Operand),
7338 Make_Identifier (Loc, Chars (Disc))));
7339 Next_Discriminant (Disc);
7342 elsif Is_Array_Type (Operand_Type) then
7343 N_Ix := First_Index (Target_Type);
7346 for J in 1 .. Number_Dimensions (Operand_Type) loop
7348 -- We convert the bounds explicitly. We use an unchecked
7349 -- conversion because bounds checks are done elsewhere.
7354 Unchecked_Convert_To (Etype (N_Ix),
7355 Make_Attribute_Reference (Loc,
7357 Duplicate_Subexpr_No_Checks
7358 (Operand, Name_Req => True),
7359 Attribute_Name => Name_First,
7360 Expressions => New_List (
7361 Make_Integer_Literal (Loc, J)))),
7364 Unchecked_Convert_To (Etype (N_Ix),
7365 Make_Attribute_Reference (Loc,
7367 Duplicate_Subexpr_No_Checks
7368 (Operand, Name_Req => True),
7369 Attribute_Name => Name_Last,
7370 Expressions => New_List (
7371 Make_Integer_Literal (Loc, J))))));
7378 Odef := New_Occurrence_Of (Target_Type, Loc);
7380 if Present (Cons) then
7382 Make_Subtype_Indication (Loc,
7383 Subtype_Mark => Odef,
7385 Make_Index_Or_Discriminant_Constraint (Loc,
7386 Constraints => Cons));
7389 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('C'));
7391 Make_Object_Declaration (Loc,
7392 Defining_Identifier => Temp,
7393 Object_Definition => Odef);
7395 Set_No_Initialization (Decl, True);
7397 -- Insert required actions. It is essential to suppress checks
7398 -- since we have suppressed default initialization, which means
7399 -- that the variable we create may have no discriminants.
7404 Make_Assignment_Statement (Loc,
7405 Name => New_Occurrence_Of (Temp, Loc),
7406 Expression => Relocate_Node (N))),
7407 Suppress => All_Checks);
7409 Rewrite (N, New_Occurrence_Of (Temp, Loc));
7412 end Handle_Changed_Representation;
7414 ----------------------
7415 -- Real_Range_Check --
7416 ----------------------
7418 -- Case of conversions to floating-point or fixed-point. If range checks
7419 -- are enabled and the target type has a range constraint, we convert:
7425 -- Tnn : typ'Base := typ'Base (x);
7426 -- [constraint_error when Tnn < typ'First or else Tnn > typ'Last]
7429 -- This is necessary when there is a conversion of integer to float or
7430 -- to fixed-point to ensure that the correct checks are made. It is not
7431 -- necessary for float to float where it is enough to simply set the
7432 -- Do_Range_Check flag.
7434 procedure Real_Range_Check is
7435 Btyp : constant Entity_Id := Base_Type (Target_Type);
7436 Lo : constant Node_Id := Type_Low_Bound (Target_Type);
7437 Hi : constant Node_Id := Type_High_Bound (Target_Type);
7438 Xtyp : constant Entity_Id := Etype (Operand);
7443 -- Nothing to do if conversion was rewritten
7445 if Nkind (N) /= N_Type_Conversion then
7449 -- Nothing to do if range checks suppressed, or target has the same
7450 -- range as the base type (or is the base type).
7452 if Range_Checks_Suppressed (Target_Type)
7453 or else (Lo = Type_Low_Bound (Btyp)
7455 Hi = Type_High_Bound (Btyp))
7460 -- Nothing to do if expression is an entity on which checks have been
7463 if Is_Entity_Name (Operand)
7464 and then Range_Checks_Suppressed (Entity (Operand))
7469 -- Nothing to do if bounds are all static and we can tell that the
7470 -- expression is within the bounds of the target. Note that if the
7471 -- operand is of an unconstrained floating-point type, then we do
7472 -- not trust it to be in range (might be infinite)
7475 S_Lo : constant Node_Id := Type_Low_Bound (Xtyp);
7476 S_Hi : constant Node_Id := Type_High_Bound (Xtyp);
7479 if (not Is_Floating_Point_Type (Xtyp)
7480 or else Is_Constrained (Xtyp))
7481 and then Compile_Time_Known_Value (S_Lo)
7482 and then Compile_Time_Known_Value (S_Hi)
7483 and then Compile_Time_Known_Value (Hi)
7484 and then Compile_Time_Known_Value (Lo)
7487 D_Lov : constant Ureal := Expr_Value_R (Lo);
7488 D_Hiv : constant Ureal := Expr_Value_R (Hi);
7493 if Is_Real_Type (Xtyp) then
7494 S_Lov := Expr_Value_R (S_Lo);
7495 S_Hiv := Expr_Value_R (S_Hi);
7497 S_Lov := UR_From_Uint (Expr_Value (S_Lo));
7498 S_Hiv := UR_From_Uint (Expr_Value (S_Hi));
7502 and then S_Lov >= D_Lov
7503 and then S_Hiv <= D_Hiv
7505 Set_Do_Range_Check (Operand, False);
7512 -- For float to float conversions, we are done
7514 if Is_Floating_Point_Type (Xtyp)
7516 Is_Floating_Point_Type (Btyp)
7521 -- Otherwise rewrite the conversion as described above
7523 Conv := Relocate_Node (N);
7525 (Subtype_Mark (Conv), New_Occurrence_Of (Btyp, Loc));
7526 Set_Etype (Conv, Btyp);
7528 -- Enable overflow except for case of integer to float conversions,
7529 -- where it is never required, since we can never have overflow in
7532 if not Is_Integer_Type (Etype (Operand)) then
7533 Enable_Overflow_Check (Conv);
7537 Make_Defining_Identifier (Loc,
7538 Chars => New_Internal_Name ('T'));
7540 Insert_Actions (N, New_List (
7541 Make_Object_Declaration (Loc,
7542 Defining_Identifier => Tnn,
7543 Object_Definition => New_Occurrence_Of (Btyp, Loc),
7544 Expression => Conv),
7546 Make_Raise_Constraint_Error (Loc,
7551 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
7553 Make_Attribute_Reference (Loc,
7554 Attribute_Name => Name_First,
7556 New_Occurrence_Of (Target_Type, Loc))),
7560 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
7562 Make_Attribute_Reference (Loc,
7563 Attribute_Name => Name_Last,
7565 New_Occurrence_Of (Target_Type, Loc)))),
7566 Reason => CE_Range_Check_Failed)));
7568 Rewrite (N, New_Occurrence_Of (Tnn, Loc));
7569 Analyze_And_Resolve (N, Btyp);
7570 end Real_Range_Check;
7572 -- Start of processing for Expand_N_Type_Conversion
7575 -- Nothing at all to do if conversion is to the identical type so remove
7576 -- the conversion completely, it is useless.
7578 if Operand_Type = Target_Type then
7579 Rewrite (N, Relocate_Node (Operand));
7583 -- Nothing to do if this is the second argument of read. This is a
7584 -- "backwards" conversion that will be handled by the specialized code
7585 -- in attribute processing.
7587 if Nkind (Parent (N)) = N_Attribute_Reference
7588 and then Attribute_Name (Parent (N)) = Name_Read
7589 and then Next (First (Expressions (Parent (N)))) = N
7594 -- Here if we may need to expand conversion
7596 -- Do validity check if validity checking operands
7598 if Validity_Checks_On
7599 and then Validity_Check_Operands
7601 Ensure_Valid (Operand);
7604 -- Special case of converting from non-standard boolean type
7606 if Is_Boolean_Type (Operand_Type)
7607 and then (Nonzero_Is_True (Operand_Type))
7609 Adjust_Condition (Operand);
7610 Set_Etype (Operand, Standard_Boolean);
7611 Operand_Type := Standard_Boolean;
7614 -- Case of converting to an access type
7616 if Is_Access_Type (Target_Type) then
7618 -- Apply an accessibility check when the conversion operand is an
7619 -- access parameter (or a renaming thereof), unless conversion was
7620 -- expanded from an Unchecked_ or Unrestricted_Access attribute.
7621 -- Note that other checks may still need to be applied below (such
7622 -- as tagged type checks).
7624 if Is_Entity_Name (Operand)
7626 (Is_Formal (Entity (Operand))
7628 (Present (Renamed_Object (Entity (Operand)))
7629 and then Is_Entity_Name (Renamed_Object (Entity (Operand)))
7631 (Entity (Renamed_Object (Entity (Operand))))))
7632 and then Ekind (Etype (Operand)) = E_Anonymous_Access_Type
7633 and then (Nkind (Original_Node (N)) /= N_Attribute_Reference
7634 or else Attribute_Name (Original_Node (N)) = Name_Access)
7636 Apply_Accessibility_Check
7637 (Operand, Target_Type, Insert_Node => Operand);
7639 -- If the level of the operand type is statically deeper than the
7640 -- level of the target type, then force Program_Error. Note that this
7641 -- can only occur for cases where the attribute is within the body of
7642 -- an instantiation (otherwise the conversion will already have been
7643 -- rejected as illegal). Note: warnings are issued by the analyzer
7644 -- for the instance cases.
7646 elsif In_Instance_Body
7647 and then Type_Access_Level (Operand_Type) >
7648 Type_Access_Level (Target_Type)
7651 Make_Raise_Program_Error (Sloc (N),
7652 Reason => PE_Accessibility_Check_Failed));
7653 Set_Etype (N, Target_Type);
7655 -- When the operand is a selected access discriminant the check needs
7656 -- to be made against the level of the object denoted by the prefix
7657 -- of the selected name. Force Program_Error for this case as well
7658 -- (this accessibility violation can only happen if within the body
7659 -- of an instantiation).
7661 elsif In_Instance_Body
7662 and then Ekind (Operand_Type) = E_Anonymous_Access_Type
7663 and then Nkind (Operand) = N_Selected_Component
7664 and then Object_Access_Level (Operand) >
7665 Type_Access_Level (Target_Type)
7668 Make_Raise_Program_Error (Sloc (N),
7669 Reason => PE_Accessibility_Check_Failed));
7670 Set_Etype (N, Target_Type);
7674 -- Case of conversions of tagged types and access to tagged types
7676 -- When needed, that is to say when the expression is class-wide, Add
7677 -- runtime a tag check for (strict) downward conversion by using the
7678 -- membership test, generating:
7680 -- [constraint_error when Operand not in Target_Type'Class]
7682 -- or in the access type case
7684 -- [constraint_error
7685 -- when Operand /= null
7686 -- and then Operand.all not in
7687 -- Designated_Type (Target_Type)'Class]
7689 if (Is_Access_Type (Target_Type)
7690 and then Is_Tagged_Type (Designated_Type (Target_Type)))
7691 or else Is_Tagged_Type (Target_Type)
7693 -- Do not do any expansion in the access type case if the parent is a
7694 -- renaming, since this is an error situation which will be caught by
7695 -- Sem_Ch8, and the expansion can interfere with this error check.
7697 if Is_Access_Type (Target_Type)
7698 and then Is_Renamed_Object (N)
7703 -- Otherwise, proceed with processing tagged conversion
7706 Actual_Op_Typ : Entity_Id;
7707 Actual_Targ_Typ : Entity_Id;
7708 Make_Conversion : Boolean := False;
7709 Root_Op_Typ : Entity_Id;
7711 procedure Make_Tag_Check (Targ_Typ : Entity_Id);
7712 -- Create a membership check to test whether Operand is a member
7713 -- of Targ_Typ. If the original Target_Type is an access, include
7714 -- a test for null value. The check is inserted at N.
7716 --------------------
7717 -- Make_Tag_Check --
7718 --------------------
7720 procedure Make_Tag_Check (Targ_Typ : Entity_Id) is
7725 -- [Constraint_Error
7726 -- when Operand /= null
7727 -- and then Operand.all not in Targ_Typ]
7729 if Is_Access_Type (Target_Type) then
7734 Left_Opnd => Duplicate_Subexpr_No_Checks (Operand),
7735 Right_Opnd => Make_Null (Loc)),
7740 Make_Explicit_Dereference (Loc,
7741 Prefix => Duplicate_Subexpr_No_Checks (Operand)),
7742 Right_Opnd => New_Reference_To (Targ_Typ, Loc)));
7745 -- [Constraint_Error when Operand not in Targ_Typ]
7750 Left_Opnd => Duplicate_Subexpr_No_Checks (Operand),
7751 Right_Opnd => New_Reference_To (Targ_Typ, Loc));
7755 Make_Raise_Constraint_Error (Loc,
7757 Reason => CE_Tag_Check_Failed));
7760 -- Start of processing
7763 if Is_Access_Type (Target_Type) then
7764 Actual_Op_Typ := Designated_Type (Operand_Type);
7765 Actual_Targ_Typ := Designated_Type (Target_Type);
7768 Actual_Op_Typ := Operand_Type;
7769 Actual_Targ_Typ := Target_Type;
7772 Root_Op_Typ := Root_Type (Actual_Op_Typ);
7774 -- Ada 2005 (AI-251): Handle interface type conversion
7776 if Is_Interface (Actual_Op_Typ) then
7777 Expand_Interface_Conversion (N, Is_Static => False);
7781 if not Tag_Checks_Suppressed (Actual_Targ_Typ) then
7783 -- Create a runtime tag check for a downward class-wide type
7786 if Is_Class_Wide_Type (Actual_Op_Typ)
7787 and then Root_Op_Typ /= Actual_Targ_Typ
7788 and then Is_Ancestor (Root_Op_Typ, Actual_Targ_Typ)
7790 Make_Tag_Check (Class_Wide_Type (Actual_Targ_Typ));
7791 Make_Conversion := True;
7794 -- AI05-0073: If the result subtype of the function is defined
7795 -- by an access_definition designating a specific tagged type
7796 -- T, a check is made that the result value is null or the tag
7797 -- of the object designated by the result value identifies T.
7798 -- Constraint_Error is raised if this check fails.
7800 if Nkind (Parent (N)) = Sinfo.N_Return_Statement then
7803 Func_Typ : Entity_Id;
7806 -- Climb scope stack looking for the enclosing function
7808 Func := Current_Scope;
7809 while Present (Func)
7810 and then Ekind (Func) /= E_Function
7812 Func := Scope (Func);
7815 -- The function's return subtype must be defined using
7816 -- an access definition.
7818 if Nkind (Result_Definition (Parent (Func))) =
7821 Func_Typ := Directly_Designated_Type (Etype (Func));
7823 -- The return subtype denotes a specific tagged type,
7824 -- in other words, a non class-wide type.
7826 if Is_Tagged_Type (Func_Typ)
7827 and then not Is_Class_Wide_Type (Func_Typ)
7829 Make_Tag_Check (Actual_Targ_Typ);
7830 Make_Conversion := True;
7836 -- We have generated a tag check for either a class-wide type
7837 -- conversion or for AI05-0073.
7839 if Make_Conversion then
7844 Make_Unchecked_Type_Conversion (Loc,
7845 Subtype_Mark => New_Occurrence_Of (Target_Type, Loc),
7846 Expression => Relocate_Node (Expression (N)));
7848 Analyze_And_Resolve (N, Target_Type);
7854 -- Case of other access type conversions
7856 elsif Is_Access_Type (Target_Type) then
7857 Apply_Constraint_Check (Operand, Target_Type);
7859 -- Case of conversions from a fixed-point type
7861 -- These conversions require special expansion and processing, found in
7862 -- the Exp_Fixd package. We ignore cases where Conversion_OK is set,
7863 -- since from a semantic point of view, these are simple integer
7864 -- conversions, which do not need further processing.
7866 elsif Is_Fixed_Point_Type (Operand_Type)
7867 and then not Conversion_OK (N)
7869 -- We should never see universal fixed at this case, since the
7870 -- expansion of the constituent divide or multiply should have
7871 -- eliminated the explicit mention of universal fixed.
7873 pragma Assert (Operand_Type /= Universal_Fixed);
7875 -- Check for special case of the conversion to universal real that
7876 -- occurs as a result of the use of a round attribute. In this case,
7877 -- the real type for the conversion is taken from the target type of
7878 -- the Round attribute and the result must be marked as rounded.
7880 if Target_Type = Universal_Real
7881 and then Nkind (Parent (N)) = N_Attribute_Reference
7882 and then Attribute_Name (Parent (N)) = Name_Round
7884 Set_Rounded_Result (N);
7885 Set_Etype (N, Etype (Parent (N)));
7888 -- Otherwise do correct fixed-conversion, but skip these if the
7889 -- Conversion_OK flag is set, because from a semantic point of
7890 -- view these are simple integer conversions needing no further
7891 -- processing (the backend will simply treat them as integers)
7893 if not Conversion_OK (N) then
7894 if Is_Fixed_Point_Type (Etype (N)) then
7895 Expand_Convert_Fixed_To_Fixed (N);
7898 elsif Is_Integer_Type (Etype (N)) then
7899 Expand_Convert_Fixed_To_Integer (N);
7902 pragma Assert (Is_Floating_Point_Type (Etype (N)));
7903 Expand_Convert_Fixed_To_Float (N);
7908 -- Case of conversions to a fixed-point type
7910 -- These conversions require special expansion and processing, found in
7911 -- the Exp_Fixd package. Again, ignore cases where Conversion_OK is set,
7912 -- since from a semantic point of view, these are simple integer
7913 -- conversions, which do not need further processing.
7915 elsif Is_Fixed_Point_Type (Target_Type)
7916 and then not Conversion_OK (N)
7918 if Is_Integer_Type (Operand_Type) then
7919 Expand_Convert_Integer_To_Fixed (N);
7922 pragma Assert (Is_Floating_Point_Type (Operand_Type));
7923 Expand_Convert_Float_To_Fixed (N);
7927 -- Case of float-to-integer conversions
7929 -- We also handle float-to-fixed conversions with Conversion_OK set
7930 -- since semantically the fixed-point target is treated as though it
7931 -- were an integer in such cases.
7933 elsif Is_Floating_Point_Type (Operand_Type)
7935 (Is_Integer_Type (Target_Type)
7937 (Is_Fixed_Point_Type (Target_Type) and then Conversion_OK (N)))
7939 -- One more check here, gcc is still not able to do conversions of
7940 -- this type with proper overflow checking, and so gigi is doing an
7941 -- approximation of what is required by doing floating-point compares
7942 -- with the end-point. But that can lose precision in some cases, and
7943 -- give a wrong result. Converting the operand to Universal_Real is
7944 -- helpful, but still does not catch all cases with 64-bit integers
7945 -- on targets with only 64-bit floats
7947 -- The above comment seems obsoleted by Apply_Float_Conversion_Check
7948 -- Can this code be removed ???
7950 if Do_Range_Check (Operand) then
7952 Make_Type_Conversion (Loc,
7954 New_Occurrence_Of (Universal_Real, Loc),
7956 Relocate_Node (Operand)));
7958 Set_Etype (Operand, Universal_Real);
7959 Enable_Range_Check (Operand);
7960 Set_Do_Range_Check (Expression (Operand), False);
7963 -- Case of array conversions
7965 -- Expansion of array conversions, add required length/range checks but
7966 -- only do this if there is no change of representation. For handling of
7967 -- this case, see Handle_Changed_Representation.
7969 elsif Is_Array_Type (Target_Type) then
7971 if Is_Constrained (Target_Type) then
7972 Apply_Length_Check (Operand, Target_Type);
7974 Apply_Range_Check (Operand, Target_Type);
7977 Handle_Changed_Representation;
7979 -- Case of conversions of discriminated types
7981 -- Add required discriminant checks if target is constrained. Again this
7982 -- change is skipped if we have a change of representation.
7984 elsif Has_Discriminants (Target_Type)
7985 and then Is_Constrained (Target_Type)
7987 Apply_Discriminant_Check (Operand, Target_Type);
7988 Handle_Changed_Representation;
7990 -- Case of all other record conversions. The only processing required
7991 -- is to check for a change of representation requiring the special
7992 -- assignment processing.
7994 elsif Is_Record_Type (Target_Type) then
7996 -- Ada 2005 (AI-216): Program_Error is raised when converting from
7997 -- a derived Unchecked_Union type to an unconstrained type that is
7998 -- not Unchecked_Union if the operand lacks inferable discriminants.
8000 if Is_Derived_Type (Operand_Type)
8001 and then Is_Unchecked_Union (Base_Type (Operand_Type))
8002 and then not Is_Constrained (Target_Type)
8003 and then not Is_Unchecked_Union (Base_Type (Target_Type))
8004 and then not Has_Inferable_Discriminants (Operand)
8006 -- To prevent Gigi from generating illegal code, we generate a
8007 -- Program_Error node, but we give it the target type of the
8011 PE : constant Node_Id := Make_Raise_Program_Error (Loc,
8012 Reason => PE_Unchecked_Union_Restriction);
8015 Set_Etype (PE, Target_Type);
8020 Handle_Changed_Representation;
8023 -- Case of conversions of enumeration types
8025 elsif Is_Enumeration_Type (Target_Type) then
8027 -- Special processing is required if there is a change of
8028 -- representation (from enumeration representation clauses)
8030 if not Same_Representation (Target_Type, Operand_Type) then
8032 -- Convert: x(y) to x'val (ytyp'val (y))
8035 Make_Attribute_Reference (Loc,
8036 Prefix => New_Occurrence_Of (Target_Type, Loc),
8037 Attribute_Name => Name_Val,
8038 Expressions => New_List (
8039 Make_Attribute_Reference (Loc,
8040 Prefix => New_Occurrence_Of (Operand_Type, Loc),
8041 Attribute_Name => Name_Pos,
8042 Expressions => New_List (Operand)))));
8044 Analyze_And_Resolve (N, Target_Type);
8047 -- Case of conversions to floating-point
8049 elsif Is_Floating_Point_Type (Target_Type) then
8053 -- At this stage, either the conversion node has been transformed into
8054 -- some other equivalent expression, or left as a conversion that can
8055 -- be handled by Gigi. The conversions that Gigi can handle are the
8058 -- Conversions with no change of representation or type
8060 -- Numeric conversions involving integer, floating- and fixed-point
8061 -- values. Fixed-point values are allowed only if Conversion_OK is
8062 -- set, i.e. if the fixed-point values are to be treated as integers.
8064 -- No other conversions should be passed to Gigi
8066 -- Check: are these rules stated in sinfo??? if so, why restate here???
8068 -- The only remaining step is to generate a range check if we still have
8069 -- a type conversion at this stage and Do_Range_Check is set. For now we
8070 -- do this only for conversions of discrete types.
8072 if Nkind (N) = N_Type_Conversion
8073 and then Is_Discrete_Type (Etype (N))
8076 Expr : constant Node_Id := Expression (N);
8081 if Do_Range_Check (Expr)
8082 and then Is_Discrete_Type (Etype (Expr))
8084 Set_Do_Range_Check (Expr, False);
8086 -- Before we do a range check, we have to deal with treating a
8087 -- fixed-point operand as an integer. The way we do this is
8088 -- simply to do an unchecked conversion to an appropriate
8089 -- integer type large enough to hold the result.
8091 -- This code is not active yet, because we are only dealing
8092 -- with discrete types so far ???
8094 if Nkind (Expr) in N_Has_Treat_Fixed_As_Integer
8095 and then Treat_Fixed_As_Integer (Expr)
8097 Ftyp := Base_Type (Etype (Expr));
8099 if Esize (Ftyp) >= Esize (Standard_Integer) then
8100 Ityp := Standard_Long_Long_Integer;
8102 Ityp := Standard_Integer;
8105 Rewrite (Expr, Unchecked_Convert_To (Ityp, Expr));
8108 -- Reset overflow flag, since the range check will include
8109 -- dealing with possible overflow, and generate the check If
8110 -- Address is either a source type or target type, suppress
8111 -- range check to avoid typing anomalies when it is a visible
8114 Set_Do_Overflow_Check (N, False);
8115 if not Is_Descendent_Of_Address (Etype (Expr))
8116 and then not Is_Descendent_Of_Address (Target_Type)
8118 Generate_Range_Check
8119 (Expr, Target_Type, CE_Range_Check_Failed);
8125 -- Final step, if the result is a type conversion involving Vax_Float
8126 -- types, then it is subject for further special processing.
8128 if Nkind (N) = N_Type_Conversion
8129 and then (Vax_Float (Operand_Type) or else Vax_Float (Target_Type))
8131 Expand_Vax_Conversion (N);
8134 end Expand_N_Type_Conversion;
8136 -----------------------------------
8137 -- Expand_N_Unchecked_Expression --
8138 -----------------------------------
8140 -- Remove the unchecked expression node from the tree. It's job was simply
8141 -- to make sure that its constituent expression was handled with checks
8142 -- off, and now that that is done, we can remove it from the tree, and
8143 -- indeed must, since gigi does not expect to see these nodes.
8145 procedure Expand_N_Unchecked_Expression (N : Node_Id) is
8146 Exp : constant Node_Id := Expression (N);
8149 Set_Assignment_OK (Exp, Assignment_OK (N) or Assignment_OK (Exp));
8151 end Expand_N_Unchecked_Expression;
8153 ----------------------------------------
8154 -- Expand_N_Unchecked_Type_Conversion --
8155 ----------------------------------------
8157 -- If this cannot be handled by Gigi and we haven't already made a
8158 -- temporary for it, do it now.
8160 procedure Expand_N_Unchecked_Type_Conversion (N : Node_Id) is
8161 Target_Type : constant Entity_Id := Etype (N);
8162 Operand : constant Node_Id := Expression (N);
8163 Operand_Type : constant Entity_Id := Etype (Operand);
8166 -- If we have a conversion of a compile time known value to a target
8167 -- type and the value is in range of the target type, then we can simply
8168 -- replace the construct by an integer literal of the correct type. We
8169 -- only apply this to integer types being converted. Possibly it may
8170 -- apply in other cases, but it is too much trouble to worry about.
8172 -- Note that we do not do this transformation if the Kill_Range_Check
8173 -- flag is set, since then the value may be outside the expected range.
8174 -- This happens in the Normalize_Scalars case.
8176 -- We also skip this if either the target or operand type is biased
8177 -- because in this case, the unchecked conversion is supposed to
8178 -- preserve the bit pattern, not the integer value.
8180 if Is_Integer_Type (Target_Type)
8181 and then not Has_Biased_Representation (Target_Type)
8182 and then Is_Integer_Type (Operand_Type)
8183 and then not Has_Biased_Representation (Operand_Type)
8184 and then Compile_Time_Known_Value (Operand)
8185 and then not Kill_Range_Check (N)
8188 Val : constant Uint := Expr_Value (Operand);
8191 if Compile_Time_Known_Value (Type_Low_Bound (Target_Type))
8193 Compile_Time_Known_Value (Type_High_Bound (Target_Type))
8195 Val >= Expr_Value (Type_Low_Bound (Target_Type))
8197 Val <= Expr_Value (Type_High_Bound (Target_Type))
8199 Rewrite (N, Make_Integer_Literal (Sloc (N), Val));
8201 -- If Address is the target type, just set the type to avoid a
8202 -- spurious type error on the literal when Address is a visible
8205 if Is_Descendent_Of_Address (Target_Type) then
8206 Set_Etype (N, Target_Type);
8208 Analyze_And_Resolve (N, Target_Type);
8216 -- Nothing to do if conversion is safe
8218 if Safe_Unchecked_Type_Conversion (N) then
8222 -- Otherwise force evaluation unless Assignment_OK flag is set (this
8223 -- flag indicates ??? -- more comments needed here)
8225 if Assignment_OK (N) then
8228 Force_Evaluation (N);
8230 end Expand_N_Unchecked_Type_Conversion;
8232 ----------------------------
8233 -- Expand_Record_Equality --
8234 ----------------------------
8236 -- For non-variant records, Equality is expanded when needed into:
8238 -- and then Lhs.Discr1 = Rhs.Discr1
8240 -- and then Lhs.Discrn = Rhs.Discrn
8241 -- and then Lhs.Cmp1 = Rhs.Cmp1
8243 -- and then Lhs.Cmpn = Rhs.Cmpn
8245 -- The expression is folded by the back-end for adjacent fields. This
8246 -- function is called for tagged record in only one occasion: for imple-
8247 -- menting predefined primitive equality (see Predefined_Primitives_Bodies)
8248 -- otherwise the primitive "=" is used directly.
8250 function Expand_Record_Equality
8255 Bodies : List_Id) return Node_Id
8257 Loc : constant Source_Ptr := Sloc (Nod);
8262 First_Time : Boolean := True;
8264 function Suitable_Element (C : Entity_Id) return Entity_Id;
8265 -- Return the first field to compare beginning with C, skipping the
8266 -- inherited components.
8268 ----------------------
8269 -- Suitable_Element --
8270 ----------------------
8272 function Suitable_Element (C : Entity_Id) return Entity_Id is
8277 elsif Ekind (C) /= E_Discriminant
8278 and then Ekind (C) /= E_Component
8280 return Suitable_Element (Next_Entity (C));
8282 elsif Is_Tagged_Type (Typ)
8283 and then C /= Original_Record_Component (C)
8285 return Suitable_Element (Next_Entity (C));
8287 elsif Chars (C) = Name_uController
8288 or else Chars (C) = Name_uTag
8290 return Suitable_Element (Next_Entity (C));
8292 elsif Is_Interface (Etype (C)) then
8293 return Suitable_Element (Next_Entity (C));
8298 end Suitable_Element;
8300 -- Start of processing for Expand_Record_Equality
8303 -- Generates the following code: (assuming that Typ has one Discr and
8304 -- component C2 is also a record)
8307 -- and then Lhs.Discr1 = Rhs.Discr1
8308 -- and then Lhs.C1 = Rhs.C1
8309 -- and then Lhs.C2.C1=Rhs.C2.C1 and then ... Lhs.C2.Cn=Rhs.C2.Cn
8311 -- and then Lhs.Cmpn = Rhs.Cmpn
8313 Result := New_Reference_To (Standard_True, Loc);
8314 C := Suitable_Element (First_Entity (Typ));
8316 while Present (C) loop
8324 First_Time := False;
8328 New_Lhs := New_Copy_Tree (Lhs);
8329 New_Rhs := New_Copy_Tree (Rhs);
8333 Expand_Composite_Equality (Nod, Etype (C),
8335 Make_Selected_Component (Loc,
8337 Selector_Name => New_Reference_To (C, Loc)),
8339 Make_Selected_Component (Loc,
8341 Selector_Name => New_Reference_To (C, Loc)),
8344 -- If some (sub)component is an unchecked_union, the whole
8345 -- operation will raise program error.
8347 if Nkind (Check) = N_Raise_Program_Error then
8349 Set_Etype (Result, Standard_Boolean);
8354 Left_Opnd => Result,
8355 Right_Opnd => Check);
8359 C := Suitable_Element (Next_Entity (C));
8363 end Expand_Record_Equality;
8365 -------------------------------------
8366 -- Fixup_Universal_Fixed_Operation --
8367 -------------------------------------
8369 procedure Fixup_Universal_Fixed_Operation (N : Node_Id) is
8370 Conv : constant Node_Id := Parent (N);
8373 -- We must have a type conversion immediately above us
8375 pragma Assert (Nkind (Conv) = N_Type_Conversion);
8377 -- Normally the type conversion gives our target type. The exception
8378 -- occurs in the case of the Round attribute, where the conversion
8379 -- will be to universal real, and our real type comes from the Round
8380 -- attribute (as well as an indication that we must round the result)
8382 if Nkind (Parent (Conv)) = N_Attribute_Reference
8383 and then Attribute_Name (Parent (Conv)) = Name_Round
8385 Set_Etype (N, Etype (Parent (Conv)));
8386 Set_Rounded_Result (N);
8388 -- Normal case where type comes from conversion above us
8391 Set_Etype (N, Etype (Conv));
8393 end Fixup_Universal_Fixed_Operation;
8395 ------------------------------
8396 -- Get_Allocator_Final_List --
8397 ------------------------------
8399 function Get_Allocator_Final_List
8402 PtrT : Entity_Id) return Entity_Id
8404 Loc : constant Source_Ptr := Sloc (N);
8406 Owner : Entity_Id := PtrT;
8407 -- The entity whose finalization list must be used to attach the
8408 -- allocated object.
8411 if Ekind (PtrT) = E_Anonymous_Access_Type then
8413 -- If the context is an access parameter, we need to create a
8414 -- non-anonymous access type in order to have a usable final list,
8415 -- because there is otherwise no pool to which the allocated object
8416 -- can belong. We create both the type and the finalization chain
8417 -- here, because freezing an internal type does not create such a
8418 -- chain. The Final_Chain that is thus created is shared by the
8419 -- access parameter. The access type is tested against the result
8420 -- type of the function to exclude allocators whose type is an
8421 -- anonymous access result type. We freeze the type at once to
8422 -- ensure that it is properly decorated for the back-end, even
8423 -- if the context and current scope is a loop.
8425 if Nkind (Associated_Node_For_Itype (PtrT))
8426 in N_Subprogram_Specification
8429 Etype (Defining_Unit_Name (Associated_Node_For_Itype (PtrT)))
8431 Owner := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
8433 Make_Full_Type_Declaration (Loc,
8434 Defining_Identifier => Owner,
8436 Make_Access_To_Object_Definition (Loc,
8437 Subtype_Indication =>
8438 New_Occurrence_Of (T, Loc))));
8440 Freeze_Before (N, Owner);
8441 Build_Final_List (N, Owner);
8442 Set_Associated_Final_Chain (PtrT, Associated_Final_Chain (Owner));
8444 -- Ada 2005 (AI-318-02): If the context is a return object
8445 -- declaration, then the anonymous return subtype is defined to have
8446 -- the same accessibility level as that of the function's result
8447 -- subtype, which means that we want the scope where the function is
8450 elsif Nkind (Associated_Node_For_Itype (PtrT)) = N_Object_Declaration
8451 and then Ekind (Scope (PtrT)) = E_Return_Statement
8453 Owner := Scope (Return_Applies_To (Scope (PtrT)));
8455 -- Case of an access discriminant, or (Ada 2005), of an anonymous
8456 -- access component or anonymous access function result: find the
8457 -- final list associated with the scope of the type. (In the
8458 -- anonymous access component kind, a list controller will have
8459 -- been allocated when freezing the record type, and PtrT has an
8460 -- Associated_Final_Chain attribute designating it.)
8462 elsif No (Associated_Final_Chain (PtrT)) then
8463 Owner := Scope (PtrT);
8467 return Find_Final_List (Owner);
8468 end Get_Allocator_Final_List;
8470 ---------------------------------
8471 -- Has_Inferable_Discriminants --
8472 ---------------------------------
8474 function Has_Inferable_Discriminants (N : Node_Id) return Boolean is
8476 function Prefix_Is_Formal_Parameter (N : Node_Id) return Boolean;
8477 -- Determines whether the left-most prefix of a selected component is a
8478 -- formal parameter in a subprogram. Assumes N is a selected component.
8480 --------------------------------
8481 -- Prefix_Is_Formal_Parameter --
8482 --------------------------------
8484 function Prefix_Is_Formal_Parameter (N : Node_Id) return Boolean is
8485 Sel_Comp : Node_Id := N;
8488 -- Move to the left-most prefix by climbing up the tree
8490 while Present (Parent (Sel_Comp))
8491 and then Nkind (Parent (Sel_Comp)) = N_Selected_Component
8493 Sel_Comp := Parent (Sel_Comp);
8496 return Ekind (Entity (Prefix (Sel_Comp))) in Formal_Kind;
8497 end Prefix_Is_Formal_Parameter;
8499 -- Start of processing for Has_Inferable_Discriminants
8502 -- For identifiers and indexed components, it is sufficient to have a
8503 -- constrained Unchecked_Union nominal subtype.
8505 if Nkind_In (N, N_Identifier, N_Indexed_Component) then
8506 return Is_Unchecked_Union (Base_Type (Etype (N)))
8508 Is_Constrained (Etype (N));
8510 -- For selected components, the subtype of the selector must be a
8511 -- constrained Unchecked_Union. If the component is subject to a
8512 -- per-object constraint, then the enclosing object must have inferable
8515 elsif Nkind (N) = N_Selected_Component then
8516 if Has_Per_Object_Constraint (Entity (Selector_Name (N))) then
8518 -- A small hack. If we have a per-object constrained selected
8519 -- component of a formal parameter, return True since we do not
8520 -- know the actual parameter association yet.
8522 if Prefix_Is_Formal_Parameter (N) then
8526 -- Otherwise, check the enclosing object and the selector
8528 return Has_Inferable_Discriminants (Prefix (N))
8530 Has_Inferable_Discriminants (Selector_Name (N));
8533 -- The call to Has_Inferable_Discriminants will determine whether
8534 -- the selector has a constrained Unchecked_Union nominal type.
8536 return Has_Inferable_Discriminants (Selector_Name (N));
8538 -- A qualified expression has inferable discriminants if its subtype
8539 -- mark is a constrained Unchecked_Union subtype.
8541 elsif Nkind (N) = N_Qualified_Expression then
8542 return Is_Unchecked_Union (Subtype_Mark (N))
8544 Is_Constrained (Subtype_Mark (N));
8549 end Has_Inferable_Discriminants;
8551 -------------------------------
8552 -- Insert_Dereference_Action --
8553 -------------------------------
8555 procedure Insert_Dereference_Action (N : Node_Id) is
8556 Loc : constant Source_Ptr := Sloc (N);
8557 Typ : constant Entity_Id := Etype (N);
8558 Pool : constant Entity_Id := Associated_Storage_Pool (Typ);
8559 Pnod : constant Node_Id := Parent (N);
8561 function Is_Checked_Storage_Pool (P : Entity_Id) return Boolean;
8562 -- Return true if type of P is derived from Checked_Pool;
8564 -----------------------------
8565 -- Is_Checked_Storage_Pool --
8566 -----------------------------
8568 function Is_Checked_Storage_Pool (P : Entity_Id) return Boolean is
8577 while T /= Etype (T) loop
8578 if Is_RTE (T, RE_Checked_Pool) then
8586 end Is_Checked_Storage_Pool;
8588 -- Start of processing for Insert_Dereference_Action
8591 pragma Assert (Nkind (Pnod) = N_Explicit_Dereference);
8593 if not (Is_Checked_Storage_Pool (Pool)
8594 and then Comes_From_Source (Original_Node (Pnod)))
8600 Make_Procedure_Call_Statement (Loc,
8601 Name => New_Reference_To (
8602 Find_Prim_Op (Etype (Pool), Name_Dereference), Loc),
8604 Parameter_Associations => New_List (
8608 New_Reference_To (Pool, Loc),
8610 -- Storage_Address. We use the attribute Pool_Address, which uses
8611 -- the pointer itself to find the address of the object, and which
8612 -- handles unconstrained arrays properly by computing the address
8613 -- of the template. i.e. the correct address of the corresponding
8616 Make_Attribute_Reference (Loc,
8617 Prefix => Duplicate_Subexpr_Move_Checks (N),
8618 Attribute_Name => Name_Pool_Address),
8620 -- Size_In_Storage_Elements
8622 Make_Op_Divide (Loc,
8624 Make_Attribute_Reference (Loc,
8626 Make_Explicit_Dereference (Loc,
8627 Duplicate_Subexpr_Move_Checks (N)),
8628 Attribute_Name => Name_Size),
8630 Make_Integer_Literal (Loc, System_Storage_Unit)),
8634 Make_Attribute_Reference (Loc,
8636 Make_Explicit_Dereference (Loc,
8637 Duplicate_Subexpr_Move_Checks (N)),
8638 Attribute_Name => Name_Alignment))));
8641 when RE_Not_Available =>
8643 end Insert_Dereference_Action;
8645 ------------------------------
8646 -- Make_Array_Comparison_Op --
8647 ------------------------------
8649 -- This is a hand-coded expansion of the following generic function:
8652 -- type elem is (<>);
8653 -- type index is (<>);
8654 -- type a is array (index range <>) of elem;
8656 -- function Gnnn (X : a; Y: a) return boolean is
8657 -- J : index := Y'first;
8660 -- if X'length = 0 then
8663 -- elsif Y'length = 0 then
8667 -- for I in X'range loop
8668 -- if X (I) = Y (J) then
8669 -- if J = Y'last then
8672 -- J := index'succ (J);
8676 -- return X (I) > Y (J);
8680 -- return X'length > Y'length;
8684 -- Note that since we are essentially doing this expansion by hand, we
8685 -- do not need to generate an actual or formal generic part, just the
8686 -- instantiated function itself.
8688 function Make_Array_Comparison_Op
8690 Nod : Node_Id) return Node_Id
8692 Loc : constant Source_Ptr := Sloc (Nod);
8694 X : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uX);
8695 Y : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uY);
8696 I : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uI);
8697 J : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uJ);
8699 Index : constant Entity_Id := Base_Type (Etype (First_Index (Typ)));
8701 Loop_Statement : Node_Id;
8702 Loop_Body : Node_Id;
8705 Final_Expr : Node_Id;
8706 Func_Body : Node_Id;
8707 Func_Name : Entity_Id;
8713 -- if J = Y'last then
8716 -- J := index'succ (J);
8720 Make_Implicit_If_Statement (Nod,
8723 Left_Opnd => New_Reference_To (J, Loc),
8725 Make_Attribute_Reference (Loc,
8726 Prefix => New_Reference_To (Y, Loc),
8727 Attribute_Name => Name_Last)),
8729 Then_Statements => New_List (
8730 Make_Exit_Statement (Loc)),
8734 Make_Assignment_Statement (Loc,
8735 Name => New_Reference_To (J, Loc),
8737 Make_Attribute_Reference (Loc,
8738 Prefix => New_Reference_To (Index, Loc),
8739 Attribute_Name => Name_Succ,
8740 Expressions => New_List (New_Reference_To (J, Loc))))));
8742 -- if X (I) = Y (J) then
8745 -- return X (I) > Y (J);
8749 Make_Implicit_If_Statement (Nod,
8753 Make_Indexed_Component (Loc,
8754 Prefix => New_Reference_To (X, Loc),
8755 Expressions => New_List (New_Reference_To (I, Loc))),
8758 Make_Indexed_Component (Loc,
8759 Prefix => New_Reference_To (Y, Loc),
8760 Expressions => New_List (New_Reference_To (J, Loc)))),
8762 Then_Statements => New_List (Inner_If),
8764 Else_Statements => New_List (
8765 Make_Simple_Return_Statement (Loc,
8769 Make_Indexed_Component (Loc,
8770 Prefix => New_Reference_To (X, Loc),
8771 Expressions => New_List (New_Reference_To (I, Loc))),
8774 Make_Indexed_Component (Loc,
8775 Prefix => New_Reference_To (Y, Loc),
8776 Expressions => New_List (
8777 New_Reference_To (J, Loc)))))));
8779 -- for I in X'range loop
8784 Make_Implicit_Loop_Statement (Nod,
8785 Identifier => Empty,
8788 Make_Iteration_Scheme (Loc,
8789 Loop_Parameter_Specification =>
8790 Make_Loop_Parameter_Specification (Loc,
8791 Defining_Identifier => I,
8792 Discrete_Subtype_Definition =>
8793 Make_Attribute_Reference (Loc,
8794 Prefix => New_Reference_To (X, Loc),
8795 Attribute_Name => Name_Range))),
8797 Statements => New_List (Loop_Body));
8799 -- if X'length = 0 then
8801 -- elsif Y'length = 0 then
8804 -- for ... loop ... end loop;
8805 -- return X'length > Y'length;
8809 Make_Attribute_Reference (Loc,
8810 Prefix => New_Reference_To (X, Loc),
8811 Attribute_Name => Name_Length);
8814 Make_Attribute_Reference (Loc,
8815 Prefix => New_Reference_To (Y, Loc),
8816 Attribute_Name => Name_Length);
8820 Left_Opnd => Length1,
8821 Right_Opnd => Length2);
8824 Make_Implicit_If_Statement (Nod,
8828 Make_Attribute_Reference (Loc,
8829 Prefix => New_Reference_To (X, Loc),
8830 Attribute_Name => Name_Length),
8832 Make_Integer_Literal (Loc, 0)),
8836 Make_Simple_Return_Statement (Loc,
8837 Expression => New_Reference_To (Standard_False, Loc))),
8839 Elsif_Parts => New_List (
8840 Make_Elsif_Part (Loc,
8844 Make_Attribute_Reference (Loc,
8845 Prefix => New_Reference_To (Y, Loc),
8846 Attribute_Name => Name_Length),
8848 Make_Integer_Literal (Loc, 0)),
8852 Make_Simple_Return_Statement (Loc,
8853 Expression => New_Reference_To (Standard_True, Loc))))),
8855 Else_Statements => New_List (
8857 Make_Simple_Return_Statement (Loc,
8858 Expression => Final_Expr)));
8862 Formals := New_List (
8863 Make_Parameter_Specification (Loc,
8864 Defining_Identifier => X,
8865 Parameter_Type => New_Reference_To (Typ, Loc)),
8867 Make_Parameter_Specification (Loc,
8868 Defining_Identifier => Y,
8869 Parameter_Type => New_Reference_To (Typ, Loc)));
8871 -- function Gnnn (...) return boolean is
8872 -- J : index := Y'first;
8877 Func_Name := Make_Defining_Identifier (Loc, New_Internal_Name ('G'));
8880 Make_Subprogram_Body (Loc,
8882 Make_Function_Specification (Loc,
8883 Defining_Unit_Name => Func_Name,
8884 Parameter_Specifications => Formals,
8885 Result_Definition => New_Reference_To (Standard_Boolean, Loc)),
8887 Declarations => New_List (
8888 Make_Object_Declaration (Loc,
8889 Defining_Identifier => J,
8890 Object_Definition => New_Reference_To (Index, Loc),
8892 Make_Attribute_Reference (Loc,
8893 Prefix => New_Reference_To (Y, Loc),
8894 Attribute_Name => Name_First))),
8896 Handled_Statement_Sequence =>
8897 Make_Handled_Sequence_Of_Statements (Loc,
8898 Statements => New_List (If_Stat)));
8901 end Make_Array_Comparison_Op;
8903 ---------------------------
8904 -- Make_Boolean_Array_Op --
8905 ---------------------------
8907 -- For logical operations on boolean arrays, expand in line the following,
8908 -- replacing 'and' with 'or' or 'xor' where needed:
8910 -- function Annn (A : typ; B: typ) return typ is
8913 -- for J in A'range loop
8914 -- C (J) := A (J) op B (J);
8919 -- Here typ is the boolean array type
8921 function Make_Boolean_Array_Op
8923 N : Node_Id) return Node_Id
8925 Loc : constant Source_Ptr := Sloc (N);
8927 A : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uA);
8928 B : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uB);
8929 C : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uC);
8930 J : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uJ);
8938 Func_Name : Entity_Id;
8939 Func_Body : Node_Id;
8940 Loop_Statement : Node_Id;
8944 Make_Indexed_Component (Loc,
8945 Prefix => New_Reference_To (A, Loc),
8946 Expressions => New_List (New_Reference_To (J, Loc)));
8949 Make_Indexed_Component (Loc,
8950 Prefix => New_Reference_To (B, Loc),
8951 Expressions => New_List (New_Reference_To (J, Loc)));
8954 Make_Indexed_Component (Loc,
8955 Prefix => New_Reference_To (C, Loc),
8956 Expressions => New_List (New_Reference_To (J, Loc)));
8958 if Nkind (N) = N_Op_And then
8964 elsif Nkind (N) = N_Op_Or then
8978 Make_Implicit_Loop_Statement (N,
8979 Identifier => Empty,
8982 Make_Iteration_Scheme (Loc,
8983 Loop_Parameter_Specification =>
8984 Make_Loop_Parameter_Specification (Loc,
8985 Defining_Identifier => J,
8986 Discrete_Subtype_Definition =>
8987 Make_Attribute_Reference (Loc,
8988 Prefix => New_Reference_To (A, Loc),
8989 Attribute_Name => Name_Range))),
8991 Statements => New_List (
8992 Make_Assignment_Statement (Loc,
8994 Expression => Op)));
8996 Formals := New_List (
8997 Make_Parameter_Specification (Loc,
8998 Defining_Identifier => A,
8999 Parameter_Type => New_Reference_To (Typ, Loc)),
9001 Make_Parameter_Specification (Loc,
9002 Defining_Identifier => B,
9003 Parameter_Type => New_Reference_To (Typ, Loc)));
9006 Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
9007 Set_Is_Inlined (Func_Name);
9010 Make_Subprogram_Body (Loc,
9012 Make_Function_Specification (Loc,
9013 Defining_Unit_Name => Func_Name,
9014 Parameter_Specifications => Formals,
9015 Result_Definition => New_Reference_To (Typ, Loc)),
9017 Declarations => New_List (
9018 Make_Object_Declaration (Loc,
9019 Defining_Identifier => C,
9020 Object_Definition => New_Reference_To (Typ, Loc))),
9022 Handled_Statement_Sequence =>
9023 Make_Handled_Sequence_Of_Statements (Loc,
9024 Statements => New_List (
9026 Make_Simple_Return_Statement (Loc,
9027 Expression => New_Reference_To (C, Loc)))));
9030 end Make_Boolean_Array_Op;
9032 ------------------------
9033 -- Rewrite_Comparison --
9034 ------------------------
9036 procedure Rewrite_Comparison (N : Node_Id) is
9037 Warning_Generated : Boolean := False;
9038 -- Set to True if first pass with Assume_Valid generates a warning in
9039 -- which case we skip the second pass to avoid warning overloaded.
9042 -- Set to Standard_True or Standard_False
9045 if Nkind (N) = N_Type_Conversion then
9046 Rewrite_Comparison (Expression (N));
9049 elsif Nkind (N) not in N_Op_Compare then
9053 -- Now start looking at the comparison in detail. We potentially go
9054 -- through this loop twice. The first time, Assume_Valid is set False
9055 -- in the call to Compile_Time_Compare. If this call results in a
9056 -- clear result of always True or Always False, that's decisive and
9057 -- we are done. Otherwise we repeat the processing with Assume_Valid
9058 -- set to True to generate additional warnings. We can stil that step
9059 -- if Constant_Condition_Warnings is False.
9061 for AV in False .. True loop
9063 Typ : constant Entity_Id := Etype (N);
9064 Op1 : constant Node_Id := Left_Opnd (N);
9065 Op2 : constant Node_Id := Right_Opnd (N);
9067 Res : constant Compare_Result :=
9068 Compile_Time_Compare (Op1, Op2, Assume_Valid => AV);
9069 -- Res indicates if compare outcome can be compile time determined
9071 True_Result : Boolean;
9072 False_Result : Boolean;
9075 case N_Op_Compare (Nkind (N)) is
9077 True_Result := Res = EQ;
9078 False_Result := Res = LT or else Res = GT or else Res = NE;
9081 True_Result := Res in Compare_GE;
9082 False_Result := Res = LT;
9085 and then Constant_Condition_Warnings
9086 and then Comes_From_Source (Original_Node (N))
9087 and then Nkind (Original_Node (N)) = N_Op_Ge
9088 and then not In_Instance
9089 and then Is_Integer_Type (Etype (Left_Opnd (N)))
9090 and then not Has_Warnings_Off (Etype (Left_Opnd (N)))
9093 ("can never be greater than, could replace by ""'=""?", N);
9094 Warning_Generated := True;
9098 True_Result := Res = GT;
9099 False_Result := Res in Compare_LE;
9102 True_Result := Res = LT;
9103 False_Result := Res in Compare_GE;
9106 True_Result := Res in Compare_LE;
9107 False_Result := Res = GT;
9110 and then Constant_Condition_Warnings
9111 and then Comes_From_Source (Original_Node (N))
9112 and then Nkind (Original_Node (N)) = N_Op_Le
9113 and then not In_Instance
9114 and then Is_Integer_Type (Etype (Left_Opnd (N)))
9115 and then not Has_Warnings_Off (Etype (Left_Opnd (N)))
9118 ("can never be less than, could replace by ""'=""?", N);
9119 Warning_Generated := True;
9123 True_Result := Res = NE or else Res = GT or else Res = LT;
9124 False_Result := Res = EQ;
9127 -- If this is the first iteration, then we actually convert the
9128 -- comparison into True or False, if the result is certain.
9131 if True_Result or False_Result then
9133 Result := Standard_True;
9135 Result := Standard_False;
9140 New_Occurrence_Of (Result, Sloc (N))));
9141 Analyze_And_Resolve (N, Typ);
9142 Warn_On_Known_Condition (N);
9146 -- If this is the second iteration (AV = True), and the original
9147 -- node comes from source and we are not in an instance, then
9148 -- give a warning if we know result would be True or False. Note
9149 -- we know Constant_Condition_Warnings is set if we get here.
9151 elsif Comes_From_Source (Original_Node (N))
9152 and then not In_Instance
9156 ("condition can only be False if invalid values present?",
9158 elsif False_Result then
9160 ("condition can only be True if invalid values present?",
9166 -- Skip second iteration if not warning on constant conditions or
9167 -- if the first iteration already generated a warning of some kind
9168 -- or if we are in any case assuming all values are valid (so that
9169 -- the first iteration took care of the valid case).
9171 exit when not Constant_Condition_Warnings;
9172 exit when Warning_Generated;
9173 exit when Assume_No_Invalid_Values;
9175 end Rewrite_Comparison;
9177 ----------------------------
9178 -- Safe_In_Place_Array_Op --
9179 ----------------------------
9181 function Safe_In_Place_Array_Op
9184 Op2 : Node_Id) return Boolean
9188 function Is_Safe_Operand (Op : Node_Id) return Boolean;
9189 -- Operand is safe if it cannot overlap part of the target of the
9190 -- operation. If the operand and the target are identical, the operand
9191 -- is safe. The operand can be empty in the case of negation.
9193 function Is_Unaliased (N : Node_Id) return Boolean;
9194 -- Check that N is a stand-alone entity
9200 function Is_Unaliased (N : Node_Id) return Boolean is
9204 and then No (Address_Clause (Entity (N)))
9205 and then No (Renamed_Object (Entity (N)));
9208 ---------------------
9209 -- Is_Safe_Operand --
9210 ---------------------
9212 function Is_Safe_Operand (Op : Node_Id) return Boolean is
9217 elsif Is_Entity_Name (Op) then
9218 return Is_Unaliased (Op);
9220 elsif Nkind_In (Op, N_Indexed_Component, N_Selected_Component) then
9221 return Is_Unaliased (Prefix (Op));
9223 elsif Nkind (Op) = N_Slice then
9225 Is_Unaliased (Prefix (Op))
9226 and then Entity (Prefix (Op)) /= Target;
9228 elsif Nkind (Op) = N_Op_Not then
9229 return Is_Safe_Operand (Right_Opnd (Op));
9234 end Is_Safe_Operand;
9236 -- Start of processing for Is_Safe_In_Place_Array_Op
9239 -- Skip this processing if the component size is different from system
9240 -- storage unit (since at least for NOT this would cause problems).
9242 if Component_Size (Etype (Lhs)) /= System_Storage_Unit then
9245 -- Cannot do in place stuff on VM_Target since cannot pass addresses
9247 elsif VM_Target /= No_VM then
9250 -- Cannot do in place stuff if non-standard Boolean representation
9252 elsif Has_Non_Standard_Rep (Component_Type (Etype (Lhs))) then
9255 elsif not Is_Unaliased (Lhs) then
9258 Target := Entity (Lhs);
9261 Is_Safe_Operand (Op1)
9262 and then Is_Safe_Operand (Op2);
9264 end Safe_In_Place_Array_Op;
9266 -----------------------
9267 -- Tagged_Membership --
9268 -----------------------
9270 -- There are two different cases to consider depending on whether the right
9271 -- operand is a class-wide type or not. If not we just compare the actual
9272 -- tag of the left expr to the target type tag:
9274 -- Left_Expr.Tag = Right_Type'Tag;
9276 -- If it is a class-wide type we use the RT function CW_Membership which is
9277 -- usually implemented by looking in the ancestor tables contained in the
9278 -- dispatch table pointed by Left_Expr.Tag for Typ'Tag
9280 -- Ada 2005 (AI-251): If it is a class-wide interface type we use the RT
9281 -- function IW_Membership which is usually implemented by looking in the
9282 -- table of abstract interface types plus the ancestor table contained in
9283 -- the dispatch table pointed by Left_Expr.Tag for Typ'Tag
9285 function Tagged_Membership (N : Node_Id) return Node_Id is
9286 Left : constant Node_Id := Left_Opnd (N);
9287 Right : constant Node_Id := Right_Opnd (N);
9288 Loc : constant Source_Ptr := Sloc (N);
9290 Left_Type : Entity_Id;
9291 Right_Type : Entity_Id;
9295 Left_Type := Etype (Left);
9296 Right_Type := Etype (Right);
9298 if Is_Class_Wide_Type (Left_Type) then
9299 Left_Type := Root_Type (Left_Type);
9303 Make_Selected_Component (Loc,
9304 Prefix => Relocate_Node (Left),
9306 New_Reference_To (First_Tag_Component (Left_Type), Loc));
9308 if Is_Class_Wide_Type (Right_Type) then
9310 -- No need to issue a run-time check if we statically know that the
9311 -- result of this membership test is always true. For example,
9312 -- considering the following declarations:
9314 -- type Iface is interface;
9315 -- type T is tagged null record;
9316 -- type DT is new T and Iface with null record;
9321 -- These membership tests are always true:
9325 -- Obj2 in Iface'Class;
9327 -- We do not need to handle cases where the membership is illegal.
9330 -- Obj1 in DT'Class; -- Compile time error
9331 -- Obj1 in Iface'Class; -- Compile time error
9333 if not Is_Class_Wide_Type (Left_Type)
9334 and then (Is_Ancestor (Etype (Right_Type), Left_Type)
9335 or else (Is_Interface (Etype (Right_Type))
9336 and then Interface_Present_In_Ancestor
9338 Iface => Etype (Right_Type))))
9340 return New_Reference_To (Standard_True, Loc);
9343 -- Ada 2005 (AI-251): Class-wide applied to interfaces
9345 if Is_Interface (Etype (Class_Wide_Type (Right_Type)))
9347 -- Support to: "Iface_CW_Typ in Typ'Class"
9349 or else Is_Interface (Left_Type)
9351 -- Issue error if IW_Membership operation not available in a
9352 -- configurable run time setting.
9354 if not RTE_Available (RE_IW_Membership) then
9356 ("dynamic membership test on interface types", N);
9361 Make_Function_Call (Loc,
9362 Name => New_Occurrence_Of (RTE (RE_IW_Membership), Loc),
9363 Parameter_Associations => New_List (
9364 Make_Attribute_Reference (Loc,
9366 Attribute_Name => Name_Address),
9369 (Access_Disp_Table (Root_Type (Right_Type)))),
9372 -- Ada 95: Normal case
9376 Build_CW_Membership (Loc,
9377 Obj_Tag_Node => Obj_Tag,
9381 (Access_Disp_Table (Root_Type (Right_Type)))),
9385 -- Right_Type is not a class-wide type
9388 -- No need to check the tag of the object if Right_Typ is abstract
9390 if Is_Abstract_Type (Right_Type) then
9391 return New_Reference_To (Standard_False, Loc);
9396 Left_Opnd => Obj_Tag,
9399 (Node (First_Elmt (Access_Disp_Table (Right_Type))), Loc));
9402 end Tagged_Membership;
9404 ------------------------------
9405 -- Unary_Op_Validity_Checks --
9406 ------------------------------
9408 procedure Unary_Op_Validity_Checks (N : Node_Id) is
9410 if Validity_Checks_On and Validity_Check_Operands then
9411 Ensure_Valid (Right_Opnd (N));
9413 end Unary_Op_Validity_Checks;
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